Commit | Line | Data |
---|---|---|
ac27a0ec | 1 | /* |
617ba13b | 2 | * linux/fs/ext4/inode.c |
ac27a0ec DK |
3 | * |
4 | * Copyright (C) 1992, 1993, 1994, 1995 | |
5 | * Remy Card (card@masi.ibp.fr) | |
6 | * Laboratoire MASI - Institut Blaise Pascal | |
7 | * Universite Pierre et Marie Curie (Paris VI) | |
8 | * | |
9 | * from | |
10 | * | |
11 | * linux/fs/minix/inode.c | |
12 | * | |
13 | * Copyright (C) 1991, 1992 Linus Torvalds | |
14 | * | |
15 | * Goal-directed block allocation by Stephen Tweedie | |
16 | * (sct@redhat.com), 1993, 1998 | |
17 | * Big-endian to little-endian byte-swapping/bitmaps by | |
18 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
19 | * 64-bit file support on 64-bit platforms by Jakub Jelinek | |
20 | * (jj@sunsite.ms.mff.cuni.cz) | |
21 | * | |
617ba13b | 22 | * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000 |
ac27a0ec DK |
23 | */ |
24 | ||
25 | #include <linux/module.h> | |
26 | #include <linux/fs.h> | |
27 | #include <linux/time.h> | |
dab291af | 28 | #include <linux/jbd2.h> |
ac27a0ec DK |
29 | #include <linux/highuid.h> |
30 | #include <linux/pagemap.h> | |
31 | #include <linux/quotaops.h> | |
32 | #include <linux/string.h> | |
33 | #include <linux/buffer_head.h> | |
34 | #include <linux/writeback.h> | |
64769240 | 35 | #include <linux/pagevec.h> |
ac27a0ec | 36 | #include <linux/mpage.h> |
e83c1397 | 37 | #include <linux/namei.h> |
ac27a0ec DK |
38 | #include <linux/uio.h> |
39 | #include <linux/bio.h> | |
4c0425ff | 40 | #include <linux/workqueue.h> |
9bffad1e | 41 | |
3dcf5451 | 42 | #include "ext4_jbd2.h" |
ac27a0ec DK |
43 | #include "xattr.h" |
44 | #include "acl.h" | |
d2a17637 | 45 | #include "ext4_extents.h" |
ac27a0ec | 46 | |
9bffad1e TT |
47 | #include <trace/events/ext4.h> |
48 | ||
a1d6cc56 AK |
49 | #define MPAGE_DA_EXTENT_TAIL 0x01 |
50 | ||
678aaf48 JK |
51 | static inline int ext4_begin_ordered_truncate(struct inode *inode, |
52 | loff_t new_size) | |
53 | { | |
7f5aa215 JK |
54 | return jbd2_journal_begin_ordered_truncate( |
55 | EXT4_SB(inode->i_sb)->s_journal, | |
56 | &EXT4_I(inode)->jinode, | |
57 | new_size); | |
678aaf48 JK |
58 | } |
59 | ||
64769240 AT |
60 | static void ext4_invalidatepage(struct page *page, unsigned long offset); |
61 | ||
ac27a0ec DK |
62 | /* |
63 | * Test whether an inode is a fast symlink. | |
64 | */ | |
617ba13b | 65 | static int ext4_inode_is_fast_symlink(struct inode *inode) |
ac27a0ec | 66 | { |
617ba13b | 67 | int ea_blocks = EXT4_I(inode)->i_file_acl ? |
ac27a0ec DK |
68 | (inode->i_sb->s_blocksize >> 9) : 0; |
69 | ||
70 | return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); | |
71 | } | |
72 | ||
ac27a0ec DK |
73 | /* |
74 | * Work out how many blocks we need to proceed with the next chunk of a | |
75 | * truncate transaction. | |
76 | */ | |
77 | static unsigned long blocks_for_truncate(struct inode *inode) | |
78 | { | |
725d26d3 | 79 | ext4_lblk_t needed; |
ac27a0ec DK |
80 | |
81 | needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); | |
82 | ||
83 | /* Give ourselves just enough room to cope with inodes in which | |
84 | * i_blocks is corrupt: we've seen disk corruptions in the past | |
85 | * which resulted in random data in an inode which looked enough | |
617ba13b | 86 | * like a regular file for ext4 to try to delete it. Things |
ac27a0ec DK |
87 | * will go a bit crazy if that happens, but at least we should |
88 | * try not to panic the whole kernel. */ | |
89 | if (needed < 2) | |
90 | needed = 2; | |
91 | ||
92 | /* But we need to bound the transaction so we don't overflow the | |
93 | * journal. */ | |
617ba13b MC |
94 | if (needed > EXT4_MAX_TRANS_DATA) |
95 | needed = EXT4_MAX_TRANS_DATA; | |
ac27a0ec | 96 | |
617ba13b | 97 | return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed; |
ac27a0ec DK |
98 | } |
99 | ||
100 | /* | |
101 | * Truncate transactions can be complex and absolutely huge. So we need to | |
102 | * be able to restart the transaction at a conventient checkpoint to make | |
103 | * sure we don't overflow the journal. | |
104 | * | |
105 | * start_transaction gets us a new handle for a truncate transaction, | |
106 | * and extend_transaction tries to extend the existing one a bit. If | |
107 | * extend fails, we need to propagate the failure up and restart the | |
108 | * transaction in the top-level truncate loop. --sct | |
109 | */ | |
110 | static handle_t *start_transaction(struct inode *inode) | |
111 | { | |
112 | handle_t *result; | |
113 | ||
617ba13b | 114 | result = ext4_journal_start(inode, blocks_for_truncate(inode)); |
ac27a0ec DK |
115 | if (!IS_ERR(result)) |
116 | return result; | |
117 | ||
617ba13b | 118 | ext4_std_error(inode->i_sb, PTR_ERR(result)); |
ac27a0ec DK |
119 | return result; |
120 | } | |
121 | ||
122 | /* | |
123 | * Try to extend this transaction for the purposes of truncation. | |
124 | * | |
125 | * Returns 0 if we managed to create more room. If we can't create more | |
126 | * room, and the transaction must be restarted we return 1. | |
127 | */ | |
128 | static int try_to_extend_transaction(handle_t *handle, struct inode *inode) | |
129 | { | |
0390131b FM |
130 | if (!ext4_handle_valid(handle)) |
131 | return 0; | |
132 | if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1)) | |
ac27a0ec | 133 | return 0; |
617ba13b | 134 | if (!ext4_journal_extend(handle, blocks_for_truncate(inode))) |
ac27a0ec DK |
135 | return 0; |
136 | return 1; | |
137 | } | |
138 | ||
139 | /* | |
140 | * Restart the transaction associated with *handle. This does a commit, | |
141 | * so before we call here everything must be consistently dirtied against | |
142 | * this transaction. | |
143 | */ | |
fa5d1113 | 144 | int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode, |
487caeef | 145 | int nblocks) |
ac27a0ec | 146 | { |
487caeef JK |
147 | int ret; |
148 | ||
149 | /* | |
150 | * Drop i_data_sem to avoid deadlock with ext4_get_blocks At this | |
151 | * moment, get_block can be called only for blocks inside i_size since | |
152 | * page cache has been already dropped and writes are blocked by | |
153 | * i_mutex. So we can safely drop the i_data_sem here. | |
154 | */ | |
0390131b | 155 | BUG_ON(EXT4_JOURNAL(inode) == NULL); |
ac27a0ec | 156 | jbd_debug(2, "restarting handle %p\n", handle); |
487caeef JK |
157 | up_write(&EXT4_I(inode)->i_data_sem); |
158 | ret = ext4_journal_restart(handle, blocks_for_truncate(inode)); | |
159 | down_write(&EXT4_I(inode)->i_data_sem); | |
fa5d1113 | 160 | ext4_discard_preallocations(inode); |
487caeef JK |
161 | |
162 | return ret; | |
ac27a0ec DK |
163 | } |
164 | ||
165 | /* | |
166 | * Called at the last iput() if i_nlink is zero. | |
167 | */ | |
af5bc92d | 168 | void ext4_delete_inode(struct inode *inode) |
ac27a0ec DK |
169 | { |
170 | handle_t *handle; | |
bc965ab3 | 171 | int err; |
ac27a0ec | 172 | |
678aaf48 JK |
173 | if (ext4_should_order_data(inode)) |
174 | ext4_begin_ordered_truncate(inode, 0); | |
ac27a0ec DK |
175 | truncate_inode_pages(&inode->i_data, 0); |
176 | ||
177 | if (is_bad_inode(inode)) | |
178 | goto no_delete; | |
179 | ||
bc965ab3 | 180 | handle = ext4_journal_start(inode, blocks_for_truncate(inode)+3); |
ac27a0ec | 181 | if (IS_ERR(handle)) { |
bc965ab3 | 182 | ext4_std_error(inode->i_sb, PTR_ERR(handle)); |
ac27a0ec DK |
183 | /* |
184 | * If we're going to skip the normal cleanup, we still need to | |
185 | * make sure that the in-core orphan linked list is properly | |
186 | * cleaned up. | |
187 | */ | |
617ba13b | 188 | ext4_orphan_del(NULL, inode); |
ac27a0ec DK |
189 | goto no_delete; |
190 | } | |
191 | ||
192 | if (IS_SYNC(inode)) | |
0390131b | 193 | ext4_handle_sync(handle); |
ac27a0ec | 194 | inode->i_size = 0; |
bc965ab3 TT |
195 | err = ext4_mark_inode_dirty(handle, inode); |
196 | if (err) { | |
197 | ext4_warning(inode->i_sb, __func__, | |
198 | "couldn't mark inode dirty (err %d)", err); | |
199 | goto stop_handle; | |
200 | } | |
ac27a0ec | 201 | if (inode->i_blocks) |
617ba13b | 202 | ext4_truncate(inode); |
bc965ab3 TT |
203 | |
204 | /* | |
205 | * ext4_ext_truncate() doesn't reserve any slop when it | |
206 | * restarts journal transactions; therefore there may not be | |
207 | * enough credits left in the handle to remove the inode from | |
208 | * the orphan list and set the dtime field. | |
209 | */ | |
0390131b | 210 | if (!ext4_handle_has_enough_credits(handle, 3)) { |
bc965ab3 TT |
211 | err = ext4_journal_extend(handle, 3); |
212 | if (err > 0) | |
213 | err = ext4_journal_restart(handle, 3); | |
214 | if (err != 0) { | |
215 | ext4_warning(inode->i_sb, __func__, | |
216 | "couldn't extend journal (err %d)", err); | |
217 | stop_handle: | |
218 | ext4_journal_stop(handle); | |
219 | goto no_delete; | |
220 | } | |
221 | } | |
222 | ||
ac27a0ec | 223 | /* |
617ba13b | 224 | * Kill off the orphan record which ext4_truncate created. |
ac27a0ec | 225 | * AKPM: I think this can be inside the above `if'. |
617ba13b | 226 | * Note that ext4_orphan_del() has to be able to cope with the |
ac27a0ec | 227 | * deletion of a non-existent orphan - this is because we don't |
617ba13b | 228 | * know if ext4_truncate() actually created an orphan record. |
ac27a0ec DK |
229 | * (Well, we could do this if we need to, but heck - it works) |
230 | */ | |
617ba13b MC |
231 | ext4_orphan_del(handle, inode); |
232 | EXT4_I(inode)->i_dtime = get_seconds(); | |
ac27a0ec DK |
233 | |
234 | /* | |
235 | * One subtle ordering requirement: if anything has gone wrong | |
236 | * (transaction abort, IO errors, whatever), then we can still | |
237 | * do these next steps (the fs will already have been marked as | |
238 | * having errors), but we can't free the inode if the mark_dirty | |
239 | * fails. | |
240 | */ | |
617ba13b | 241 | if (ext4_mark_inode_dirty(handle, inode)) |
ac27a0ec DK |
242 | /* If that failed, just do the required in-core inode clear. */ |
243 | clear_inode(inode); | |
244 | else | |
617ba13b MC |
245 | ext4_free_inode(handle, inode); |
246 | ext4_journal_stop(handle); | |
ac27a0ec DK |
247 | return; |
248 | no_delete: | |
249 | clear_inode(inode); /* We must guarantee clearing of inode... */ | |
250 | } | |
251 | ||
252 | typedef struct { | |
253 | __le32 *p; | |
254 | __le32 key; | |
255 | struct buffer_head *bh; | |
256 | } Indirect; | |
257 | ||
258 | static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) | |
259 | { | |
260 | p->key = *(p->p = v); | |
261 | p->bh = bh; | |
262 | } | |
263 | ||
ac27a0ec | 264 | /** |
617ba13b | 265 | * ext4_block_to_path - parse the block number into array of offsets |
ac27a0ec DK |
266 | * @inode: inode in question (we are only interested in its superblock) |
267 | * @i_block: block number to be parsed | |
268 | * @offsets: array to store the offsets in | |
8c55e204 DK |
269 | * @boundary: set this non-zero if the referred-to block is likely to be |
270 | * followed (on disk) by an indirect block. | |
ac27a0ec | 271 | * |
617ba13b | 272 | * To store the locations of file's data ext4 uses a data structure common |
ac27a0ec DK |
273 | * for UNIX filesystems - tree of pointers anchored in the inode, with |
274 | * data blocks at leaves and indirect blocks in intermediate nodes. | |
275 | * This function translates the block number into path in that tree - | |
276 | * return value is the path length and @offsets[n] is the offset of | |
277 | * pointer to (n+1)th node in the nth one. If @block is out of range | |
278 | * (negative or too large) warning is printed and zero returned. | |
279 | * | |
280 | * Note: function doesn't find node addresses, so no IO is needed. All | |
281 | * we need to know is the capacity of indirect blocks (taken from the | |
282 | * inode->i_sb). | |
283 | */ | |
284 | ||
285 | /* | |
286 | * Portability note: the last comparison (check that we fit into triple | |
287 | * indirect block) is spelled differently, because otherwise on an | |
288 | * architecture with 32-bit longs and 8Kb pages we might get into trouble | |
289 | * if our filesystem had 8Kb blocks. We might use long long, but that would | |
290 | * kill us on x86. Oh, well, at least the sign propagation does not matter - | |
291 | * i_block would have to be negative in the very beginning, so we would not | |
292 | * get there at all. | |
293 | */ | |
294 | ||
617ba13b | 295 | static int ext4_block_to_path(struct inode *inode, |
de9a55b8 TT |
296 | ext4_lblk_t i_block, |
297 | ext4_lblk_t offsets[4], int *boundary) | |
ac27a0ec | 298 | { |
617ba13b MC |
299 | int ptrs = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
300 | int ptrs_bits = EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb); | |
301 | const long direct_blocks = EXT4_NDIR_BLOCKS, | |
ac27a0ec DK |
302 | indirect_blocks = ptrs, |
303 | double_blocks = (1 << (ptrs_bits * 2)); | |
304 | int n = 0; | |
305 | int final = 0; | |
306 | ||
c333e073 | 307 | if (i_block < direct_blocks) { |
ac27a0ec DK |
308 | offsets[n++] = i_block; |
309 | final = direct_blocks; | |
af5bc92d | 310 | } else if ((i_block -= direct_blocks) < indirect_blocks) { |
617ba13b | 311 | offsets[n++] = EXT4_IND_BLOCK; |
ac27a0ec DK |
312 | offsets[n++] = i_block; |
313 | final = ptrs; | |
314 | } else if ((i_block -= indirect_blocks) < double_blocks) { | |
617ba13b | 315 | offsets[n++] = EXT4_DIND_BLOCK; |
ac27a0ec DK |
316 | offsets[n++] = i_block >> ptrs_bits; |
317 | offsets[n++] = i_block & (ptrs - 1); | |
318 | final = ptrs; | |
319 | } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { | |
617ba13b | 320 | offsets[n++] = EXT4_TIND_BLOCK; |
ac27a0ec DK |
321 | offsets[n++] = i_block >> (ptrs_bits * 2); |
322 | offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); | |
323 | offsets[n++] = i_block & (ptrs - 1); | |
324 | final = ptrs; | |
325 | } else { | |
e2b46574 | 326 | ext4_warning(inode->i_sb, "ext4_block_to_path", |
de9a55b8 TT |
327 | "block %lu > max in inode %lu", |
328 | i_block + direct_blocks + | |
329 | indirect_blocks + double_blocks, inode->i_ino); | |
ac27a0ec DK |
330 | } |
331 | if (boundary) | |
332 | *boundary = final - 1 - (i_block & (ptrs - 1)); | |
333 | return n; | |
334 | } | |
335 | ||
fe2c8191 | 336 | static int __ext4_check_blockref(const char *function, struct inode *inode, |
6fd058f7 TT |
337 | __le32 *p, unsigned int max) |
338 | { | |
f73953c0 | 339 | __le32 *bref = p; |
6fd058f7 TT |
340 | unsigned int blk; |
341 | ||
fe2c8191 | 342 | while (bref < p+max) { |
6fd058f7 | 343 | blk = le32_to_cpu(*bref++); |
de9a55b8 TT |
344 | if (blk && |
345 | unlikely(!ext4_data_block_valid(EXT4_SB(inode->i_sb), | |
6fd058f7 | 346 | blk, 1))) { |
fe2c8191 | 347 | ext4_error(inode->i_sb, function, |
6fd058f7 TT |
348 | "invalid block reference %u " |
349 | "in inode #%lu", blk, inode->i_ino); | |
de9a55b8 TT |
350 | return -EIO; |
351 | } | |
352 | } | |
353 | return 0; | |
fe2c8191 TN |
354 | } |
355 | ||
356 | ||
357 | #define ext4_check_indirect_blockref(inode, bh) \ | |
de9a55b8 | 358 | __ext4_check_blockref(__func__, inode, (__le32 *)(bh)->b_data, \ |
fe2c8191 TN |
359 | EXT4_ADDR_PER_BLOCK((inode)->i_sb)) |
360 | ||
361 | #define ext4_check_inode_blockref(inode) \ | |
de9a55b8 | 362 | __ext4_check_blockref(__func__, inode, EXT4_I(inode)->i_data, \ |
fe2c8191 TN |
363 | EXT4_NDIR_BLOCKS) |
364 | ||
ac27a0ec | 365 | /** |
617ba13b | 366 | * ext4_get_branch - read the chain of indirect blocks leading to data |
ac27a0ec DK |
367 | * @inode: inode in question |
368 | * @depth: depth of the chain (1 - direct pointer, etc.) | |
369 | * @offsets: offsets of pointers in inode/indirect blocks | |
370 | * @chain: place to store the result | |
371 | * @err: here we store the error value | |
372 | * | |
373 | * Function fills the array of triples <key, p, bh> and returns %NULL | |
374 | * if everything went OK or the pointer to the last filled triple | |
375 | * (incomplete one) otherwise. Upon the return chain[i].key contains | |
376 | * the number of (i+1)-th block in the chain (as it is stored in memory, | |
377 | * i.e. little-endian 32-bit), chain[i].p contains the address of that | |
378 | * number (it points into struct inode for i==0 and into the bh->b_data | |
379 | * for i>0) and chain[i].bh points to the buffer_head of i-th indirect | |
380 | * block for i>0 and NULL for i==0. In other words, it holds the block | |
381 | * numbers of the chain, addresses they were taken from (and where we can | |
382 | * verify that chain did not change) and buffer_heads hosting these | |
383 | * numbers. | |
384 | * | |
385 | * Function stops when it stumbles upon zero pointer (absent block) | |
386 | * (pointer to last triple returned, *@err == 0) | |
387 | * or when it gets an IO error reading an indirect block | |
388 | * (ditto, *@err == -EIO) | |
ac27a0ec DK |
389 | * or when it reads all @depth-1 indirect blocks successfully and finds |
390 | * the whole chain, all way to the data (returns %NULL, *err == 0). | |
c278bfec AK |
391 | * |
392 | * Need to be called with | |
0e855ac8 | 393 | * down_read(&EXT4_I(inode)->i_data_sem) |
ac27a0ec | 394 | */ |
725d26d3 AK |
395 | static Indirect *ext4_get_branch(struct inode *inode, int depth, |
396 | ext4_lblk_t *offsets, | |
ac27a0ec DK |
397 | Indirect chain[4], int *err) |
398 | { | |
399 | struct super_block *sb = inode->i_sb; | |
400 | Indirect *p = chain; | |
401 | struct buffer_head *bh; | |
402 | ||
403 | *err = 0; | |
404 | /* i_data is not going away, no lock needed */ | |
af5bc92d | 405 | add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets); |
ac27a0ec DK |
406 | if (!p->key) |
407 | goto no_block; | |
408 | while (--depth) { | |
fe2c8191 TN |
409 | bh = sb_getblk(sb, le32_to_cpu(p->key)); |
410 | if (unlikely(!bh)) | |
ac27a0ec | 411 | goto failure; |
de9a55b8 | 412 | |
fe2c8191 TN |
413 | if (!bh_uptodate_or_lock(bh)) { |
414 | if (bh_submit_read(bh) < 0) { | |
415 | put_bh(bh); | |
416 | goto failure; | |
417 | } | |
418 | /* validate block references */ | |
419 | if (ext4_check_indirect_blockref(inode, bh)) { | |
420 | put_bh(bh); | |
421 | goto failure; | |
422 | } | |
423 | } | |
de9a55b8 | 424 | |
af5bc92d | 425 | add_chain(++p, bh, (__le32 *)bh->b_data + *++offsets); |
ac27a0ec DK |
426 | /* Reader: end */ |
427 | if (!p->key) | |
428 | goto no_block; | |
429 | } | |
430 | return NULL; | |
431 | ||
ac27a0ec DK |
432 | failure: |
433 | *err = -EIO; | |
434 | no_block: | |
435 | return p; | |
436 | } | |
437 | ||
438 | /** | |
617ba13b | 439 | * ext4_find_near - find a place for allocation with sufficient locality |
ac27a0ec DK |
440 | * @inode: owner |
441 | * @ind: descriptor of indirect block. | |
442 | * | |
1cc8dcf5 | 443 | * This function returns the preferred place for block allocation. |
ac27a0ec DK |
444 | * It is used when heuristic for sequential allocation fails. |
445 | * Rules are: | |
446 | * + if there is a block to the left of our position - allocate near it. | |
447 | * + if pointer will live in indirect block - allocate near that block. | |
448 | * + if pointer will live in inode - allocate in the same | |
449 | * cylinder group. | |
450 | * | |
451 | * In the latter case we colour the starting block by the callers PID to | |
452 | * prevent it from clashing with concurrent allocations for a different inode | |
453 | * in the same block group. The PID is used here so that functionally related | |
454 | * files will be close-by on-disk. | |
455 | * | |
456 | * Caller must make sure that @ind is valid and will stay that way. | |
457 | */ | |
617ba13b | 458 | static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind) |
ac27a0ec | 459 | { |
617ba13b | 460 | struct ext4_inode_info *ei = EXT4_I(inode); |
af5bc92d | 461 | __le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data; |
ac27a0ec | 462 | __le32 *p; |
617ba13b | 463 | ext4_fsblk_t bg_start; |
74d3487f | 464 | ext4_fsblk_t last_block; |
617ba13b | 465 | ext4_grpblk_t colour; |
a4912123 TT |
466 | ext4_group_t block_group; |
467 | int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); | |
ac27a0ec DK |
468 | |
469 | /* Try to find previous block */ | |
470 | for (p = ind->p - 1; p >= start; p--) { | |
471 | if (*p) | |
472 | return le32_to_cpu(*p); | |
473 | } | |
474 | ||
475 | /* No such thing, so let's try location of indirect block */ | |
476 | if (ind->bh) | |
477 | return ind->bh->b_blocknr; | |
478 | ||
479 | /* | |
480 | * It is going to be referred to from the inode itself? OK, just put it | |
481 | * into the same cylinder group then. | |
482 | */ | |
a4912123 TT |
483 | block_group = ei->i_block_group; |
484 | if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { | |
485 | block_group &= ~(flex_size-1); | |
486 | if (S_ISREG(inode->i_mode)) | |
487 | block_group++; | |
488 | } | |
489 | bg_start = ext4_group_first_block_no(inode->i_sb, block_group); | |
74d3487f VC |
490 | last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; |
491 | ||
a4912123 TT |
492 | /* |
493 | * If we are doing delayed allocation, we don't need take | |
494 | * colour into account. | |
495 | */ | |
496 | if (test_opt(inode->i_sb, DELALLOC)) | |
497 | return bg_start; | |
498 | ||
74d3487f VC |
499 | if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) |
500 | colour = (current->pid % 16) * | |
617ba13b | 501 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
74d3487f VC |
502 | else |
503 | colour = (current->pid % 16) * ((last_block - bg_start) / 16); | |
ac27a0ec DK |
504 | return bg_start + colour; |
505 | } | |
506 | ||
507 | /** | |
1cc8dcf5 | 508 | * ext4_find_goal - find a preferred place for allocation. |
ac27a0ec DK |
509 | * @inode: owner |
510 | * @block: block we want | |
ac27a0ec | 511 | * @partial: pointer to the last triple within a chain |
ac27a0ec | 512 | * |
1cc8dcf5 | 513 | * Normally this function find the preferred place for block allocation, |
fb01bfda | 514 | * returns it. |
fb0a387d ES |
515 | * Because this is only used for non-extent files, we limit the block nr |
516 | * to 32 bits. | |
ac27a0ec | 517 | */ |
725d26d3 | 518 | static ext4_fsblk_t ext4_find_goal(struct inode *inode, ext4_lblk_t block, |
de9a55b8 | 519 | Indirect *partial) |
ac27a0ec | 520 | { |
fb0a387d ES |
521 | ext4_fsblk_t goal; |
522 | ||
ac27a0ec | 523 | /* |
c2ea3fde | 524 | * XXX need to get goal block from mballoc's data structures |
ac27a0ec | 525 | */ |
ac27a0ec | 526 | |
fb0a387d ES |
527 | goal = ext4_find_near(inode, partial); |
528 | goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; | |
529 | return goal; | |
ac27a0ec DK |
530 | } |
531 | ||
532 | /** | |
617ba13b | 533 | * ext4_blks_to_allocate: Look up the block map and count the number |
ac27a0ec DK |
534 | * of direct blocks need to be allocated for the given branch. |
535 | * | |
536 | * @branch: chain of indirect blocks | |
537 | * @k: number of blocks need for indirect blocks | |
538 | * @blks: number of data blocks to be mapped. | |
539 | * @blocks_to_boundary: the offset in the indirect block | |
540 | * | |
541 | * return the total number of blocks to be allocate, including the | |
542 | * direct and indirect blocks. | |
543 | */ | |
498e5f24 | 544 | static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned int blks, |
de9a55b8 | 545 | int blocks_to_boundary) |
ac27a0ec | 546 | { |
498e5f24 | 547 | unsigned int count = 0; |
ac27a0ec DK |
548 | |
549 | /* | |
550 | * Simple case, [t,d]Indirect block(s) has not allocated yet | |
551 | * then it's clear blocks on that path have not allocated | |
552 | */ | |
553 | if (k > 0) { | |
554 | /* right now we don't handle cross boundary allocation */ | |
555 | if (blks < blocks_to_boundary + 1) | |
556 | count += blks; | |
557 | else | |
558 | count += blocks_to_boundary + 1; | |
559 | return count; | |
560 | } | |
561 | ||
562 | count++; | |
563 | while (count < blks && count <= blocks_to_boundary && | |
564 | le32_to_cpu(*(branch[0].p + count)) == 0) { | |
565 | count++; | |
566 | } | |
567 | return count; | |
568 | } | |
569 | ||
570 | /** | |
617ba13b | 571 | * ext4_alloc_blocks: multiple allocate blocks needed for a branch |
ac27a0ec DK |
572 | * @indirect_blks: the number of blocks need to allocate for indirect |
573 | * blocks | |
574 | * | |
575 | * @new_blocks: on return it will store the new block numbers for | |
576 | * the indirect blocks(if needed) and the first direct block, | |
577 | * @blks: on return it will store the total number of allocated | |
578 | * direct blocks | |
579 | */ | |
617ba13b | 580 | static int ext4_alloc_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
581 | ext4_lblk_t iblock, ext4_fsblk_t goal, |
582 | int indirect_blks, int blks, | |
583 | ext4_fsblk_t new_blocks[4], int *err) | |
ac27a0ec | 584 | { |
815a1130 | 585 | struct ext4_allocation_request ar; |
ac27a0ec | 586 | int target, i; |
7061eba7 | 587 | unsigned long count = 0, blk_allocated = 0; |
ac27a0ec | 588 | int index = 0; |
617ba13b | 589 | ext4_fsblk_t current_block = 0; |
ac27a0ec DK |
590 | int ret = 0; |
591 | ||
592 | /* | |
593 | * Here we try to allocate the requested multiple blocks at once, | |
594 | * on a best-effort basis. | |
595 | * To build a branch, we should allocate blocks for | |
596 | * the indirect blocks(if not allocated yet), and at least | |
597 | * the first direct block of this branch. That's the | |
598 | * minimum number of blocks need to allocate(required) | |
599 | */ | |
7061eba7 AK |
600 | /* first we try to allocate the indirect blocks */ |
601 | target = indirect_blks; | |
602 | while (target > 0) { | |
ac27a0ec DK |
603 | count = target; |
604 | /* allocating blocks for indirect blocks and direct blocks */ | |
7061eba7 AK |
605 | current_block = ext4_new_meta_blocks(handle, inode, |
606 | goal, &count, err); | |
ac27a0ec DK |
607 | if (*err) |
608 | goto failed_out; | |
609 | ||
fb0a387d ES |
610 | BUG_ON(current_block + count > EXT4_MAX_BLOCK_FILE_PHYS); |
611 | ||
ac27a0ec DK |
612 | target -= count; |
613 | /* allocate blocks for indirect blocks */ | |
614 | while (index < indirect_blks && count) { | |
615 | new_blocks[index++] = current_block++; | |
616 | count--; | |
617 | } | |
7061eba7 AK |
618 | if (count > 0) { |
619 | /* | |
620 | * save the new block number | |
621 | * for the first direct block | |
622 | */ | |
623 | new_blocks[index] = current_block; | |
624 | printk(KERN_INFO "%s returned more blocks than " | |
625 | "requested\n", __func__); | |
626 | WARN_ON(1); | |
ac27a0ec | 627 | break; |
7061eba7 | 628 | } |
ac27a0ec DK |
629 | } |
630 | ||
7061eba7 AK |
631 | target = blks - count ; |
632 | blk_allocated = count; | |
633 | if (!target) | |
634 | goto allocated; | |
635 | /* Now allocate data blocks */ | |
815a1130 TT |
636 | memset(&ar, 0, sizeof(ar)); |
637 | ar.inode = inode; | |
638 | ar.goal = goal; | |
639 | ar.len = target; | |
640 | ar.logical = iblock; | |
641 | if (S_ISREG(inode->i_mode)) | |
642 | /* enable in-core preallocation only for regular files */ | |
643 | ar.flags = EXT4_MB_HINT_DATA; | |
644 | ||
645 | current_block = ext4_mb_new_blocks(handle, &ar, err); | |
fb0a387d | 646 | BUG_ON(current_block + ar.len > EXT4_MAX_BLOCK_FILE_PHYS); |
815a1130 | 647 | |
7061eba7 AK |
648 | if (*err && (target == blks)) { |
649 | /* | |
650 | * if the allocation failed and we didn't allocate | |
651 | * any blocks before | |
652 | */ | |
653 | goto failed_out; | |
654 | } | |
655 | if (!*err) { | |
656 | if (target == blks) { | |
de9a55b8 TT |
657 | /* |
658 | * save the new block number | |
659 | * for the first direct block | |
660 | */ | |
7061eba7 AK |
661 | new_blocks[index] = current_block; |
662 | } | |
815a1130 | 663 | blk_allocated += ar.len; |
7061eba7 AK |
664 | } |
665 | allocated: | |
ac27a0ec | 666 | /* total number of blocks allocated for direct blocks */ |
7061eba7 | 667 | ret = blk_allocated; |
ac27a0ec DK |
668 | *err = 0; |
669 | return ret; | |
670 | failed_out: | |
af5bc92d | 671 | for (i = 0; i < index; i++) |
e6362609 | 672 | ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, 0); |
ac27a0ec DK |
673 | return ret; |
674 | } | |
675 | ||
676 | /** | |
617ba13b | 677 | * ext4_alloc_branch - allocate and set up a chain of blocks. |
ac27a0ec DK |
678 | * @inode: owner |
679 | * @indirect_blks: number of allocated indirect blocks | |
680 | * @blks: number of allocated direct blocks | |
681 | * @offsets: offsets (in the blocks) to store the pointers to next. | |
682 | * @branch: place to store the chain in. | |
683 | * | |
684 | * This function allocates blocks, zeroes out all but the last one, | |
685 | * links them into chain and (if we are synchronous) writes them to disk. | |
686 | * In other words, it prepares a branch that can be spliced onto the | |
687 | * inode. It stores the information about that chain in the branch[], in | |
617ba13b | 688 | * the same format as ext4_get_branch() would do. We are calling it after |
ac27a0ec DK |
689 | * we had read the existing part of chain and partial points to the last |
690 | * triple of that (one with zero ->key). Upon the exit we have the same | |
617ba13b | 691 | * picture as after the successful ext4_get_block(), except that in one |
ac27a0ec DK |
692 | * place chain is disconnected - *branch->p is still zero (we did not |
693 | * set the last link), but branch->key contains the number that should | |
694 | * be placed into *branch->p to fill that gap. | |
695 | * | |
696 | * If allocation fails we free all blocks we've allocated (and forget | |
697 | * their buffer_heads) and return the error value the from failed | |
617ba13b | 698 | * ext4_alloc_block() (normally -ENOSPC). Otherwise we set the chain |
ac27a0ec DK |
699 | * as described above and return 0. |
700 | */ | |
617ba13b | 701 | static int ext4_alloc_branch(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
702 | ext4_lblk_t iblock, int indirect_blks, |
703 | int *blks, ext4_fsblk_t goal, | |
704 | ext4_lblk_t *offsets, Indirect *branch) | |
ac27a0ec DK |
705 | { |
706 | int blocksize = inode->i_sb->s_blocksize; | |
707 | int i, n = 0; | |
708 | int err = 0; | |
709 | struct buffer_head *bh; | |
710 | int num; | |
617ba13b MC |
711 | ext4_fsblk_t new_blocks[4]; |
712 | ext4_fsblk_t current_block; | |
ac27a0ec | 713 | |
7061eba7 | 714 | num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks, |
ac27a0ec DK |
715 | *blks, new_blocks, &err); |
716 | if (err) | |
717 | return err; | |
718 | ||
719 | branch[0].key = cpu_to_le32(new_blocks[0]); | |
720 | /* | |
721 | * metadata blocks and data blocks are allocated. | |
722 | */ | |
723 | for (n = 1; n <= indirect_blks; n++) { | |
724 | /* | |
725 | * Get buffer_head for parent block, zero it out | |
726 | * and set the pointer to new one, then send | |
727 | * parent to disk. | |
728 | */ | |
729 | bh = sb_getblk(inode->i_sb, new_blocks[n-1]); | |
730 | branch[n].bh = bh; | |
731 | lock_buffer(bh); | |
732 | BUFFER_TRACE(bh, "call get_create_access"); | |
617ba13b | 733 | err = ext4_journal_get_create_access(handle, bh); |
ac27a0ec | 734 | if (err) { |
6487a9d3 CW |
735 | /* Don't brelse(bh) here; it's done in |
736 | * ext4_journal_forget() below */ | |
ac27a0ec | 737 | unlock_buffer(bh); |
ac27a0ec DK |
738 | goto failed; |
739 | } | |
740 | ||
741 | memset(bh->b_data, 0, blocksize); | |
742 | branch[n].p = (__le32 *) bh->b_data + offsets[n]; | |
743 | branch[n].key = cpu_to_le32(new_blocks[n]); | |
744 | *branch[n].p = branch[n].key; | |
af5bc92d | 745 | if (n == indirect_blks) { |
ac27a0ec DK |
746 | current_block = new_blocks[n]; |
747 | /* | |
748 | * End of chain, update the last new metablock of | |
749 | * the chain to point to the new allocated | |
750 | * data blocks numbers | |
751 | */ | |
de9a55b8 | 752 | for (i = 1; i < num; i++) |
ac27a0ec DK |
753 | *(branch[n].p + i) = cpu_to_le32(++current_block); |
754 | } | |
755 | BUFFER_TRACE(bh, "marking uptodate"); | |
756 | set_buffer_uptodate(bh); | |
757 | unlock_buffer(bh); | |
758 | ||
0390131b FM |
759 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
760 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
761 | if (err) |
762 | goto failed; | |
763 | } | |
764 | *blks = num; | |
765 | return err; | |
766 | failed: | |
767 | /* Allocation failed, free what we already allocated */ | |
e6362609 | 768 | ext4_free_blocks(handle, inode, 0, new_blocks[0], 1, 0); |
ac27a0ec | 769 | for (i = 1; i <= n ; i++) { |
b7e57e7c | 770 | /* |
e6362609 TT |
771 | * branch[i].bh is newly allocated, so there is no |
772 | * need to revoke the block, which is why we don't | |
773 | * need to set EXT4_FREE_BLOCKS_METADATA. | |
b7e57e7c | 774 | */ |
e6362609 TT |
775 | ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, |
776 | EXT4_FREE_BLOCKS_FORGET); | |
ac27a0ec | 777 | } |
e6362609 TT |
778 | for (i = n+1; i < indirect_blks; i++) |
779 | ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, 0); | |
ac27a0ec | 780 | |
e6362609 | 781 | ext4_free_blocks(handle, inode, 0, new_blocks[i], num, 0); |
ac27a0ec DK |
782 | |
783 | return err; | |
784 | } | |
785 | ||
786 | /** | |
617ba13b | 787 | * ext4_splice_branch - splice the allocated branch onto inode. |
ac27a0ec DK |
788 | * @inode: owner |
789 | * @block: (logical) number of block we are adding | |
790 | * @chain: chain of indirect blocks (with a missing link - see | |
617ba13b | 791 | * ext4_alloc_branch) |
ac27a0ec DK |
792 | * @where: location of missing link |
793 | * @num: number of indirect blocks we are adding | |
794 | * @blks: number of direct blocks we are adding | |
795 | * | |
796 | * This function fills the missing link and does all housekeeping needed in | |
797 | * inode (->i_blocks, etc.). In case of success we end up with the full | |
798 | * chain to new block and return 0. | |
799 | */ | |
617ba13b | 800 | static int ext4_splice_branch(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
801 | ext4_lblk_t block, Indirect *where, int num, |
802 | int blks) | |
ac27a0ec DK |
803 | { |
804 | int i; | |
805 | int err = 0; | |
617ba13b | 806 | ext4_fsblk_t current_block; |
ac27a0ec | 807 | |
ac27a0ec DK |
808 | /* |
809 | * If we're splicing into a [td]indirect block (as opposed to the | |
810 | * inode) then we need to get write access to the [td]indirect block | |
811 | * before the splice. | |
812 | */ | |
813 | if (where->bh) { | |
814 | BUFFER_TRACE(where->bh, "get_write_access"); | |
617ba13b | 815 | err = ext4_journal_get_write_access(handle, where->bh); |
ac27a0ec DK |
816 | if (err) |
817 | goto err_out; | |
818 | } | |
819 | /* That's it */ | |
820 | ||
821 | *where->p = where->key; | |
822 | ||
823 | /* | |
824 | * Update the host buffer_head or inode to point to more just allocated | |
825 | * direct blocks blocks | |
826 | */ | |
827 | if (num == 0 && blks > 1) { | |
828 | current_block = le32_to_cpu(where->key) + 1; | |
829 | for (i = 1; i < blks; i++) | |
af5bc92d | 830 | *(where->p + i) = cpu_to_le32(current_block++); |
ac27a0ec DK |
831 | } |
832 | ||
ac27a0ec | 833 | /* We are done with atomic stuff, now do the rest of housekeeping */ |
ac27a0ec DK |
834 | /* had we spliced it onto indirect block? */ |
835 | if (where->bh) { | |
836 | /* | |
837 | * If we spliced it onto an indirect block, we haven't | |
838 | * altered the inode. Note however that if it is being spliced | |
839 | * onto an indirect block at the very end of the file (the | |
840 | * file is growing) then we *will* alter the inode to reflect | |
841 | * the new i_size. But that is not done here - it is done in | |
617ba13b | 842 | * generic_commit_write->__mark_inode_dirty->ext4_dirty_inode. |
ac27a0ec DK |
843 | */ |
844 | jbd_debug(5, "splicing indirect only\n"); | |
0390131b FM |
845 | BUFFER_TRACE(where->bh, "call ext4_handle_dirty_metadata"); |
846 | err = ext4_handle_dirty_metadata(handle, inode, where->bh); | |
ac27a0ec DK |
847 | if (err) |
848 | goto err_out; | |
849 | } else { | |
850 | /* | |
851 | * OK, we spliced it into the inode itself on a direct block. | |
ac27a0ec | 852 | */ |
41591750 | 853 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
854 | jbd_debug(5, "splicing direct\n"); |
855 | } | |
856 | return err; | |
857 | ||
858 | err_out: | |
859 | for (i = 1; i <= num; i++) { | |
b7e57e7c | 860 | /* |
e6362609 TT |
861 | * branch[i].bh is newly allocated, so there is no |
862 | * need to revoke the block, which is why we don't | |
863 | * need to set EXT4_FREE_BLOCKS_METADATA. | |
b7e57e7c | 864 | */ |
e6362609 TT |
865 | ext4_free_blocks(handle, inode, where[i].bh, 0, 1, |
866 | EXT4_FREE_BLOCKS_FORGET); | |
ac27a0ec | 867 | } |
e6362609 TT |
868 | ext4_free_blocks(handle, inode, 0, le32_to_cpu(where[num].key), |
869 | blks, 0); | |
ac27a0ec DK |
870 | |
871 | return err; | |
872 | } | |
873 | ||
874 | /* | |
b920c755 TT |
875 | * The ext4_ind_get_blocks() function handles non-extents inodes |
876 | * (i.e., using the traditional indirect/double-indirect i_blocks | |
877 | * scheme) for ext4_get_blocks(). | |
878 | * | |
ac27a0ec DK |
879 | * Allocation strategy is simple: if we have to allocate something, we will |
880 | * have to go the whole way to leaf. So let's do it before attaching anything | |
881 | * to tree, set linkage between the newborn blocks, write them if sync is | |
882 | * required, recheck the path, free and repeat if check fails, otherwise | |
883 | * set the last missing link (that will protect us from any truncate-generated | |
884 | * removals - all blocks on the path are immune now) and possibly force the | |
885 | * write on the parent block. | |
886 | * That has a nice additional property: no special recovery from the failed | |
887 | * allocations is needed - we simply release blocks and do not touch anything | |
888 | * reachable from inode. | |
889 | * | |
890 | * `handle' can be NULL if create == 0. | |
891 | * | |
ac27a0ec DK |
892 | * return > 0, # of blocks mapped or allocated. |
893 | * return = 0, if plain lookup failed. | |
894 | * return < 0, error case. | |
c278bfec | 895 | * |
b920c755 TT |
896 | * The ext4_ind_get_blocks() function should be called with |
897 | * down_write(&EXT4_I(inode)->i_data_sem) if allocating filesystem | |
898 | * blocks (i.e., flags has EXT4_GET_BLOCKS_CREATE set) or | |
899 | * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system | |
900 | * blocks. | |
ac27a0ec | 901 | */ |
e4d996ca | 902 | static int ext4_ind_get_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
903 | ext4_lblk_t iblock, unsigned int maxblocks, |
904 | struct buffer_head *bh_result, | |
905 | int flags) | |
ac27a0ec DK |
906 | { |
907 | int err = -EIO; | |
725d26d3 | 908 | ext4_lblk_t offsets[4]; |
ac27a0ec DK |
909 | Indirect chain[4]; |
910 | Indirect *partial; | |
617ba13b | 911 | ext4_fsblk_t goal; |
ac27a0ec DK |
912 | int indirect_blks; |
913 | int blocks_to_boundary = 0; | |
914 | int depth; | |
ac27a0ec | 915 | int count = 0; |
617ba13b | 916 | ext4_fsblk_t first_block = 0; |
ac27a0ec | 917 | |
a86c6181 | 918 | J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)); |
c2177057 | 919 | J_ASSERT(handle != NULL || (flags & EXT4_GET_BLOCKS_CREATE) == 0); |
725d26d3 | 920 | depth = ext4_block_to_path(inode, iblock, offsets, |
de9a55b8 | 921 | &blocks_to_boundary); |
ac27a0ec DK |
922 | |
923 | if (depth == 0) | |
924 | goto out; | |
925 | ||
617ba13b | 926 | partial = ext4_get_branch(inode, depth, offsets, chain, &err); |
ac27a0ec DK |
927 | |
928 | /* Simplest case - block found, no allocation needed */ | |
929 | if (!partial) { | |
930 | first_block = le32_to_cpu(chain[depth - 1].key); | |
931 | clear_buffer_new(bh_result); | |
932 | count++; | |
933 | /*map more blocks*/ | |
934 | while (count < maxblocks && count <= blocks_to_boundary) { | |
617ba13b | 935 | ext4_fsblk_t blk; |
ac27a0ec | 936 | |
ac27a0ec DK |
937 | blk = le32_to_cpu(*(chain[depth-1].p + count)); |
938 | ||
939 | if (blk == first_block + count) | |
940 | count++; | |
941 | else | |
942 | break; | |
943 | } | |
c278bfec | 944 | goto got_it; |
ac27a0ec DK |
945 | } |
946 | ||
947 | /* Next simple case - plain lookup or failed read of indirect block */ | |
c2177057 | 948 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0 || err == -EIO) |
ac27a0ec DK |
949 | goto cleanup; |
950 | ||
ac27a0ec | 951 | /* |
c2ea3fde | 952 | * Okay, we need to do block allocation. |
ac27a0ec | 953 | */ |
fb01bfda | 954 | goal = ext4_find_goal(inode, iblock, partial); |
ac27a0ec DK |
955 | |
956 | /* the number of blocks need to allocate for [d,t]indirect blocks */ | |
957 | indirect_blks = (chain + depth) - partial - 1; | |
958 | ||
959 | /* | |
960 | * Next look up the indirect map to count the totoal number of | |
961 | * direct blocks to allocate for this branch. | |
962 | */ | |
617ba13b | 963 | count = ext4_blks_to_allocate(partial, indirect_blks, |
ac27a0ec DK |
964 | maxblocks, blocks_to_boundary); |
965 | /* | |
617ba13b | 966 | * Block out ext4_truncate while we alter the tree |
ac27a0ec | 967 | */ |
7061eba7 | 968 | err = ext4_alloc_branch(handle, inode, iblock, indirect_blks, |
de9a55b8 TT |
969 | &count, goal, |
970 | offsets + (partial - chain), partial); | |
ac27a0ec DK |
971 | |
972 | /* | |
617ba13b | 973 | * The ext4_splice_branch call will free and forget any buffers |
ac27a0ec DK |
974 | * on the new chain if there is a failure, but that risks using |
975 | * up transaction credits, especially for bitmaps where the | |
976 | * credits cannot be returned. Can we handle this somehow? We | |
977 | * may need to return -EAGAIN upwards in the worst case. --sct | |
978 | */ | |
979 | if (!err) | |
617ba13b | 980 | err = ext4_splice_branch(handle, inode, iblock, |
de9a55b8 | 981 | partial, indirect_blks, count); |
2bba702d | 982 | if (err) |
ac27a0ec DK |
983 | goto cleanup; |
984 | ||
985 | set_buffer_new(bh_result); | |
b436b9be JK |
986 | |
987 | ext4_update_inode_fsync_trans(handle, inode, 1); | |
ac27a0ec DK |
988 | got_it: |
989 | map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); | |
990 | if (count > blocks_to_boundary) | |
991 | set_buffer_boundary(bh_result); | |
992 | err = count; | |
993 | /* Clean up and exit */ | |
994 | partial = chain + depth - 1; /* the whole chain */ | |
995 | cleanup: | |
996 | while (partial > chain) { | |
997 | BUFFER_TRACE(partial->bh, "call brelse"); | |
998 | brelse(partial->bh); | |
999 | partial--; | |
1000 | } | |
1001 | BUFFER_TRACE(bh_result, "returned"); | |
1002 | out: | |
1003 | return err; | |
1004 | } | |
1005 | ||
a9e7f447 DM |
1006 | #ifdef CONFIG_QUOTA |
1007 | qsize_t *ext4_get_reserved_space(struct inode *inode) | |
60e58e0f | 1008 | { |
a9e7f447 | 1009 | return &EXT4_I(inode)->i_reserved_quota; |
60e58e0f | 1010 | } |
a9e7f447 | 1011 | #endif |
9d0be502 | 1012 | |
12219aea AK |
1013 | /* |
1014 | * Calculate the number of metadata blocks need to reserve | |
9d0be502 | 1015 | * to allocate a new block at @lblocks for non extent file based file |
12219aea | 1016 | */ |
9d0be502 TT |
1017 | static int ext4_indirect_calc_metadata_amount(struct inode *inode, |
1018 | sector_t lblock) | |
12219aea | 1019 | { |
9d0be502 TT |
1020 | struct ext4_inode_info *ei = EXT4_I(inode); |
1021 | int dind_mask = EXT4_ADDR_PER_BLOCK(inode->i_sb) - 1; | |
1022 | int blk_bits; | |
12219aea | 1023 | |
9d0be502 TT |
1024 | if (lblock < EXT4_NDIR_BLOCKS) |
1025 | return 0; | |
12219aea | 1026 | |
9d0be502 | 1027 | lblock -= EXT4_NDIR_BLOCKS; |
12219aea | 1028 | |
9d0be502 TT |
1029 | if (ei->i_da_metadata_calc_len && |
1030 | (lblock & dind_mask) == ei->i_da_metadata_calc_last_lblock) { | |
1031 | ei->i_da_metadata_calc_len++; | |
1032 | return 0; | |
1033 | } | |
1034 | ei->i_da_metadata_calc_last_lblock = lblock & dind_mask; | |
1035 | ei->i_da_metadata_calc_len = 1; | |
1036 | blk_bits = roundup_pow_of_two(lblock + 1); | |
1037 | return (blk_bits / EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb)) + 1; | |
12219aea AK |
1038 | } |
1039 | ||
1040 | /* | |
1041 | * Calculate the number of metadata blocks need to reserve | |
9d0be502 | 1042 | * to allocate a block located at @lblock |
12219aea | 1043 | */ |
9d0be502 | 1044 | static int ext4_calc_metadata_amount(struct inode *inode, sector_t lblock) |
12219aea AK |
1045 | { |
1046 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) | |
9d0be502 | 1047 | return ext4_ext_calc_metadata_amount(inode, lblock); |
12219aea | 1048 | |
9d0be502 | 1049 | return ext4_indirect_calc_metadata_amount(inode, lblock); |
12219aea AK |
1050 | } |
1051 | ||
0637c6f4 TT |
1052 | /* |
1053 | * Called with i_data_sem down, which is important since we can call | |
1054 | * ext4_discard_preallocations() from here. | |
1055 | */ | |
5f634d06 AK |
1056 | void ext4_da_update_reserve_space(struct inode *inode, |
1057 | int used, int quota_claim) | |
12219aea AK |
1058 | { |
1059 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
0637c6f4 | 1060 | struct ext4_inode_info *ei = EXT4_I(inode); |
5f634d06 | 1061 | int mdb_free = 0, allocated_meta_blocks = 0; |
0637c6f4 TT |
1062 | |
1063 | spin_lock(&ei->i_block_reservation_lock); | |
1064 | if (unlikely(used > ei->i_reserved_data_blocks)) { | |
1065 | ext4_msg(inode->i_sb, KERN_NOTICE, "%s: ino %lu, used %d " | |
1066 | "with only %d reserved data blocks\n", | |
1067 | __func__, inode->i_ino, used, | |
1068 | ei->i_reserved_data_blocks); | |
1069 | WARN_ON(1); | |
1070 | used = ei->i_reserved_data_blocks; | |
1071 | } | |
12219aea | 1072 | |
0637c6f4 TT |
1073 | /* Update per-inode reservations */ |
1074 | ei->i_reserved_data_blocks -= used; | |
1075 | used += ei->i_allocated_meta_blocks; | |
1076 | ei->i_reserved_meta_blocks -= ei->i_allocated_meta_blocks; | |
5f634d06 | 1077 | allocated_meta_blocks = ei->i_allocated_meta_blocks; |
0637c6f4 TT |
1078 | ei->i_allocated_meta_blocks = 0; |
1079 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, used); | |
6bc6e63f | 1080 | |
0637c6f4 TT |
1081 | if (ei->i_reserved_data_blocks == 0) { |
1082 | /* | |
1083 | * We can release all of the reserved metadata blocks | |
1084 | * only when we have written all of the delayed | |
1085 | * allocation blocks. | |
1086 | */ | |
ee5f4d9c TT |
1087 | mdb_free = ei->i_reserved_meta_blocks; |
1088 | ei->i_reserved_meta_blocks = 0; | |
9d0be502 | 1089 | ei->i_da_metadata_calc_len = 0; |
6bc6e63f | 1090 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free); |
6bc6e63f | 1091 | } |
12219aea | 1092 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
60e58e0f | 1093 | |
0637c6f4 | 1094 | /* Update quota subsystem */ |
5f634d06 AK |
1095 | if (quota_claim) { |
1096 | vfs_dq_claim_block(inode, used); | |
1097 | if (mdb_free) | |
1098 | vfs_dq_release_reservation_block(inode, mdb_free); | |
1099 | } else { | |
1100 | /* | |
1101 | * We did fallocate with an offset that is already delayed | |
1102 | * allocated. So on delayed allocated writeback we should | |
1103 | * not update the quota for allocated blocks. But then | |
1104 | * converting an fallocate region to initialized region would | |
1105 | * have caused a metadata allocation. So claim quota for | |
1106 | * that | |
1107 | */ | |
1108 | if (allocated_meta_blocks) | |
1109 | vfs_dq_claim_block(inode, allocated_meta_blocks); | |
1110 | vfs_dq_release_reservation_block(inode, mdb_free + used); | |
1111 | } | |
d6014301 AK |
1112 | |
1113 | /* | |
1114 | * If we have done all the pending block allocations and if | |
1115 | * there aren't any writers on the inode, we can discard the | |
1116 | * inode's preallocations. | |
1117 | */ | |
0637c6f4 TT |
1118 | if ((ei->i_reserved_data_blocks == 0) && |
1119 | (atomic_read(&inode->i_writecount) == 0)) | |
d6014301 | 1120 | ext4_discard_preallocations(inode); |
12219aea AK |
1121 | } |
1122 | ||
80e42468 TT |
1123 | static int check_block_validity(struct inode *inode, const char *msg, |
1124 | sector_t logical, sector_t phys, int len) | |
6fd058f7 TT |
1125 | { |
1126 | if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), phys, len)) { | |
80e42468 | 1127 | ext4_error(inode->i_sb, msg, |
6fd058f7 TT |
1128 | "inode #%lu logical block %llu mapped to %llu " |
1129 | "(size %d)", inode->i_ino, | |
1130 | (unsigned long long) logical, | |
1131 | (unsigned long long) phys, len); | |
6fd058f7 TT |
1132 | return -EIO; |
1133 | } | |
1134 | return 0; | |
1135 | } | |
1136 | ||
55138e0b | 1137 | /* |
1f94533d TT |
1138 | * Return the number of contiguous dirty pages in a given inode |
1139 | * starting at page frame idx. | |
55138e0b TT |
1140 | */ |
1141 | static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx, | |
1142 | unsigned int max_pages) | |
1143 | { | |
1144 | struct address_space *mapping = inode->i_mapping; | |
1145 | pgoff_t index; | |
1146 | struct pagevec pvec; | |
1147 | pgoff_t num = 0; | |
1148 | int i, nr_pages, done = 0; | |
1149 | ||
1150 | if (max_pages == 0) | |
1151 | return 0; | |
1152 | pagevec_init(&pvec, 0); | |
1153 | while (!done) { | |
1154 | index = idx; | |
1155 | nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
1156 | PAGECACHE_TAG_DIRTY, | |
1157 | (pgoff_t)PAGEVEC_SIZE); | |
1158 | if (nr_pages == 0) | |
1159 | break; | |
1160 | for (i = 0; i < nr_pages; i++) { | |
1161 | struct page *page = pvec.pages[i]; | |
1162 | struct buffer_head *bh, *head; | |
1163 | ||
1164 | lock_page(page); | |
1165 | if (unlikely(page->mapping != mapping) || | |
1166 | !PageDirty(page) || | |
1167 | PageWriteback(page) || | |
1168 | page->index != idx) { | |
1169 | done = 1; | |
1170 | unlock_page(page); | |
1171 | break; | |
1172 | } | |
1f94533d TT |
1173 | if (page_has_buffers(page)) { |
1174 | bh = head = page_buffers(page); | |
1175 | do { | |
1176 | if (!buffer_delay(bh) && | |
1177 | !buffer_unwritten(bh)) | |
1178 | done = 1; | |
1179 | bh = bh->b_this_page; | |
1180 | } while (!done && (bh != head)); | |
1181 | } | |
55138e0b TT |
1182 | unlock_page(page); |
1183 | if (done) | |
1184 | break; | |
1185 | idx++; | |
1186 | num++; | |
1187 | if (num >= max_pages) | |
1188 | break; | |
1189 | } | |
1190 | pagevec_release(&pvec); | |
1191 | } | |
1192 | return num; | |
1193 | } | |
1194 | ||
f5ab0d1f | 1195 | /* |
12b7ac17 | 1196 | * The ext4_get_blocks() function tries to look up the requested blocks, |
2b2d6d01 | 1197 | * and returns if the blocks are already mapped. |
f5ab0d1f | 1198 | * |
f5ab0d1f MC |
1199 | * Otherwise it takes the write lock of the i_data_sem and allocate blocks |
1200 | * and store the allocated blocks in the result buffer head and mark it | |
1201 | * mapped. | |
1202 | * | |
1203 | * If file type is extents based, it will call ext4_ext_get_blocks(), | |
e4d996ca | 1204 | * Otherwise, call with ext4_ind_get_blocks() to handle indirect mapping |
f5ab0d1f MC |
1205 | * based files |
1206 | * | |
1207 | * On success, it returns the number of blocks being mapped or allocate. | |
1208 | * if create==0 and the blocks are pre-allocated and uninitialized block, | |
1209 | * the result buffer head is unmapped. If the create ==1, it will make sure | |
1210 | * the buffer head is mapped. | |
1211 | * | |
1212 | * It returns 0 if plain look up failed (blocks have not been allocated), in | |
1213 | * that casem, buffer head is unmapped | |
1214 | * | |
1215 | * It returns the error in case of allocation failure. | |
1216 | */ | |
12b7ac17 TT |
1217 | int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block, |
1218 | unsigned int max_blocks, struct buffer_head *bh, | |
c2177057 | 1219 | int flags) |
0e855ac8 AK |
1220 | { |
1221 | int retval; | |
f5ab0d1f MC |
1222 | |
1223 | clear_buffer_mapped(bh); | |
2a8964d6 | 1224 | clear_buffer_unwritten(bh); |
f5ab0d1f | 1225 | |
0031462b MC |
1226 | ext_debug("ext4_get_blocks(): inode %lu, flag %d, max_blocks %u," |
1227 | "logical block %lu\n", inode->i_ino, flags, max_blocks, | |
1228 | (unsigned long)block); | |
4df3d265 | 1229 | /* |
b920c755 TT |
1230 | * Try to see if we can get the block without requesting a new |
1231 | * file system block. | |
4df3d265 AK |
1232 | */ |
1233 | down_read((&EXT4_I(inode)->i_data_sem)); | |
1234 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { | |
1235 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, | |
c2177057 | 1236 | bh, 0); |
0e855ac8 | 1237 | } else { |
e4d996ca | 1238 | retval = ext4_ind_get_blocks(handle, inode, block, max_blocks, |
c2177057 | 1239 | bh, 0); |
0e855ac8 | 1240 | } |
4df3d265 | 1241 | up_read((&EXT4_I(inode)->i_data_sem)); |
f5ab0d1f | 1242 | |
6fd058f7 | 1243 | if (retval > 0 && buffer_mapped(bh)) { |
80e42468 TT |
1244 | int ret = check_block_validity(inode, "file system corruption", |
1245 | block, bh->b_blocknr, retval); | |
6fd058f7 TT |
1246 | if (ret != 0) |
1247 | return ret; | |
1248 | } | |
1249 | ||
f5ab0d1f | 1250 | /* If it is only a block(s) look up */ |
c2177057 | 1251 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) |
f5ab0d1f MC |
1252 | return retval; |
1253 | ||
1254 | /* | |
1255 | * Returns if the blocks have already allocated | |
1256 | * | |
1257 | * Note that if blocks have been preallocated | |
1258 | * ext4_ext_get_block() returns th create = 0 | |
1259 | * with buffer head unmapped. | |
1260 | */ | |
1261 | if (retval > 0 && buffer_mapped(bh)) | |
4df3d265 AK |
1262 | return retval; |
1263 | ||
2a8964d6 AK |
1264 | /* |
1265 | * When we call get_blocks without the create flag, the | |
1266 | * BH_Unwritten flag could have gotten set if the blocks | |
1267 | * requested were part of a uninitialized extent. We need to | |
1268 | * clear this flag now that we are committed to convert all or | |
1269 | * part of the uninitialized extent to be an initialized | |
1270 | * extent. This is because we need to avoid the combination | |
1271 | * of BH_Unwritten and BH_Mapped flags being simultaneously | |
1272 | * set on the buffer_head. | |
1273 | */ | |
1274 | clear_buffer_unwritten(bh); | |
1275 | ||
4df3d265 | 1276 | /* |
f5ab0d1f MC |
1277 | * New blocks allocate and/or writing to uninitialized extent |
1278 | * will possibly result in updating i_data, so we take | |
1279 | * the write lock of i_data_sem, and call get_blocks() | |
1280 | * with create == 1 flag. | |
4df3d265 AK |
1281 | */ |
1282 | down_write((&EXT4_I(inode)->i_data_sem)); | |
d2a17637 MC |
1283 | |
1284 | /* | |
1285 | * if the caller is from delayed allocation writeout path | |
1286 | * we have already reserved fs blocks for allocation | |
1287 | * let the underlying get_block() function know to | |
1288 | * avoid double accounting | |
1289 | */ | |
c2177057 | 1290 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) |
d2a17637 | 1291 | EXT4_I(inode)->i_delalloc_reserved_flag = 1; |
4df3d265 AK |
1292 | /* |
1293 | * We need to check for EXT4 here because migrate | |
1294 | * could have changed the inode type in between | |
1295 | */ | |
0e855ac8 AK |
1296 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
1297 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, | |
c2177057 | 1298 | bh, flags); |
0e855ac8 | 1299 | } else { |
e4d996ca | 1300 | retval = ext4_ind_get_blocks(handle, inode, block, |
c2177057 | 1301 | max_blocks, bh, flags); |
267e4db9 AK |
1302 | |
1303 | if (retval > 0 && buffer_new(bh)) { | |
1304 | /* | |
1305 | * We allocated new blocks which will result in | |
1306 | * i_data's format changing. Force the migrate | |
1307 | * to fail by clearing migrate flags | |
1308 | */ | |
1b9c12f4 | 1309 | EXT4_I(inode)->i_state &= ~EXT4_STATE_EXT_MIGRATE; |
267e4db9 | 1310 | } |
d2a17637 | 1311 | |
5f634d06 AK |
1312 | /* |
1313 | * Update reserved blocks/metadata blocks after successful | |
1314 | * block allocation which had been deferred till now. We don't | |
1315 | * support fallocate for non extent files. So we can update | |
1316 | * reserve space here. | |
1317 | */ | |
1318 | if ((retval > 0) && | |
1296cc85 | 1319 | (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)) |
5f634d06 AK |
1320 | ext4_da_update_reserve_space(inode, retval, 1); |
1321 | } | |
2ac3b6e0 | 1322 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) |
d2a17637 | 1323 | EXT4_I(inode)->i_delalloc_reserved_flag = 0; |
2ac3b6e0 | 1324 | |
4df3d265 | 1325 | up_write((&EXT4_I(inode)->i_data_sem)); |
6fd058f7 | 1326 | if (retval > 0 && buffer_mapped(bh)) { |
80e42468 TT |
1327 | int ret = check_block_validity(inode, "file system " |
1328 | "corruption after allocation", | |
1329 | block, bh->b_blocknr, retval); | |
6fd058f7 TT |
1330 | if (ret != 0) |
1331 | return ret; | |
1332 | } | |
0e855ac8 AK |
1333 | return retval; |
1334 | } | |
1335 | ||
f3bd1f3f MC |
1336 | /* Maximum number of blocks we map for direct IO at once. */ |
1337 | #define DIO_MAX_BLOCKS 4096 | |
1338 | ||
6873fa0d ES |
1339 | int ext4_get_block(struct inode *inode, sector_t iblock, |
1340 | struct buffer_head *bh_result, int create) | |
ac27a0ec | 1341 | { |
3e4fdaf8 | 1342 | handle_t *handle = ext4_journal_current_handle(); |
7fb5409d | 1343 | int ret = 0, started = 0; |
ac27a0ec | 1344 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; |
f3bd1f3f | 1345 | int dio_credits; |
ac27a0ec | 1346 | |
7fb5409d JK |
1347 | if (create && !handle) { |
1348 | /* Direct IO write... */ | |
1349 | if (max_blocks > DIO_MAX_BLOCKS) | |
1350 | max_blocks = DIO_MAX_BLOCKS; | |
f3bd1f3f MC |
1351 | dio_credits = ext4_chunk_trans_blocks(inode, max_blocks); |
1352 | handle = ext4_journal_start(inode, dio_credits); | |
7fb5409d | 1353 | if (IS_ERR(handle)) { |
ac27a0ec | 1354 | ret = PTR_ERR(handle); |
7fb5409d | 1355 | goto out; |
ac27a0ec | 1356 | } |
7fb5409d | 1357 | started = 1; |
ac27a0ec DK |
1358 | } |
1359 | ||
12b7ac17 | 1360 | ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result, |
c2177057 | 1361 | create ? EXT4_GET_BLOCKS_CREATE : 0); |
7fb5409d JK |
1362 | if (ret > 0) { |
1363 | bh_result->b_size = (ret << inode->i_blkbits); | |
1364 | ret = 0; | |
ac27a0ec | 1365 | } |
7fb5409d JK |
1366 | if (started) |
1367 | ext4_journal_stop(handle); | |
1368 | out: | |
ac27a0ec DK |
1369 | return ret; |
1370 | } | |
1371 | ||
1372 | /* | |
1373 | * `handle' can be NULL if create is zero | |
1374 | */ | |
617ba13b | 1375 | struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, |
725d26d3 | 1376 | ext4_lblk_t block, int create, int *errp) |
ac27a0ec DK |
1377 | { |
1378 | struct buffer_head dummy; | |
1379 | int fatal = 0, err; | |
03f5d8bc | 1380 | int flags = 0; |
ac27a0ec DK |
1381 | |
1382 | J_ASSERT(handle != NULL || create == 0); | |
1383 | ||
1384 | dummy.b_state = 0; | |
1385 | dummy.b_blocknr = -1000; | |
1386 | buffer_trace_init(&dummy.b_history); | |
c2177057 TT |
1387 | if (create) |
1388 | flags |= EXT4_GET_BLOCKS_CREATE; | |
1389 | err = ext4_get_blocks(handle, inode, block, 1, &dummy, flags); | |
ac27a0ec | 1390 | /* |
c2177057 TT |
1391 | * ext4_get_blocks() returns number of blocks mapped. 0 in |
1392 | * case of a HOLE. | |
ac27a0ec DK |
1393 | */ |
1394 | if (err > 0) { | |
1395 | if (err > 1) | |
1396 | WARN_ON(1); | |
1397 | err = 0; | |
1398 | } | |
1399 | *errp = err; | |
1400 | if (!err && buffer_mapped(&dummy)) { | |
1401 | struct buffer_head *bh; | |
1402 | bh = sb_getblk(inode->i_sb, dummy.b_blocknr); | |
1403 | if (!bh) { | |
1404 | *errp = -EIO; | |
1405 | goto err; | |
1406 | } | |
1407 | if (buffer_new(&dummy)) { | |
1408 | J_ASSERT(create != 0); | |
ac39849d | 1409 | J_ASSERT(handle != NULL); |
ac27a0ec DK |
1410 | |
1411 | /* | |
1412 | * Now that we do not always journal data, we should | |
1413 | * keep in mind whether this should always journal the | |
1414 | * new buffer as metadata. For now, regular file | |
617ba13b | 1415 | * writes use ext4_get_block instead, so it's not a |
ac27a0ec DK |
1416 | * problem. |
1417 | */ | |
1418 | lock_buffer(bh); | |
1419 | BUFFER_TRACE(bh, "call get_create_access"); | |
617ba13b | 1420 | fatal = ext4_journal_get_create_access(handle, bh); |
ac27a0ec | 1421 | if (!fatal && !buffer_uptodate(bh)) { |
af5bc92d | 1422 | memset(bh->b_data, 0, inode->i_sb->s_blocksize); |
ac27a0ec DK |
1423 | set_buffer_uptodate(bh); |
1424 | } | |
1425 | unlock_buffer(bh); | |
0390131b FM |
1426 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
1427 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
1428 | if (!fatal) |
1429 | fatal = err; | |
1430 | } else { | |
1431 | BUFFER_TRACE(bh, "not a new buffer"); | |
1432 | } | |
1433 | if (fatal) { | |
1434 | *errp = fatal; | |
1435 | brelse(bh); | |
1436 | bh = NULL; | |
1437 | } | |
1438 | return bh; | |
1439 | } | |
1440 | err: | |
1441 | return NULL; | |
1442 | } | |
1443 | ||
617ba13b | 1444 | struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode, |
725d26d3 | 1445 | ext4_lblk_t block, int create, int *err) |
ac27a0ec | 1446 | { |
af5bc92d | 1447 | struct buffer_head *bh; |
ac27a0ec | 1448 | |
617ba13b | 1449 | bh = ext4_getblk(handle, inode, block, create, err); |
ac27a0ec DK |
1450 | if (!bh) |
1451 | return bh; | |
1452 | if (buffer_uptodate(bh)) | |
1453 | return bh; | |
1454 | ll_rw_block(READ_META, 1, &bh); | |
1455 | wait_on_buffer(bh); | |
1456 | if (buffer_uptodate(bh)) | |
1457 | return bh; | |
1458 | put_bh(bh); | |
1459 | *err = -EIO; | |
1460 | return NULL; | |
1461 | } | |
1462 | ||
af5bc92d TT |
1463 | static int walk_page_buffers(handle_t *handle, |
1464 | struct buffer_head *head, | |
1465 | unsigned from, | |
1466 | unsigned to, | |
1467 | int *partial, | |
1468 | int (*fn)(handle_t *handle, | |
1469 | struct buffer_head *bh)) | |
ac27a0ec DK |
1470 | { |
1471 | struct buffer_head *bh; | |
1472 | unsigned block_start, block_end; | |
1473 | unsigned blocksize = head->b_size; | |
1474 | int err, ret = 0; | |
1475 | struct buffer_head *next; | |
1476 | ||
af5bc92d TT |
1477 | for (bh = head, block_start = 0; |
1478 | ret == 0 && (bh != head || !block_start); | |
de9a55b8 | 1479 | block_start = block_end, bh = next) { |
ac27a0ec DK |
1480 | next = bh->b_this_page; |
1481 | block_end = block_start + blocksize; | |
1482 | if (block_end <= from || block_start >= to) { | |
1483 | if (partial && !buffer_uptodate(bh)) | |
1484 | *partial = 1; | |
1485 | continue; | |
1486 | } | |
1487 | err = (*fn)(handle, bh); | |
1488 | if (!ret) | |
1489 | ret = err; | |
1490 | } | |
1491 | return ret; | |
1492 | } | |
1493 | ||
1494 | /* | |
1495 | * To preserve ordering, it is essential that the hole instantiation and | |
1496 | * the data write be encapsulated in a single transaction. We cannot | |
617ba13b | 1497 | * close off a transaction and start a new one between the ext4_get_block() |
dab291af | 1498 | * and the commit_write(). So doing the jbd2_journal_start at the start of |
ac27a0ec DK |
1499 | * prepare_write() is the right place. |
1500 | * | |
617ba13b MC |
1501 | * Also, this function can nest inside ext4_writepage() -> |
1502 | * block_write_full_page(). In that case, we *know* that ext4_writepage() | |
ac27a0ec DK |
1503 | * has generated enough buffer credits to do the whole page. So we won't |
1504 | * block on the journal in that case, which is good, because the caller may | |
1505 | * be PF_MEMALLOC. | |
1506 | * | |
617ba13b | 1507 | * By accident, ext4 can be reentered when a transaction is open via |
ac27a0ec DK |
1508 | * quota file writes. If we were to commit the transaction while thus |
1509 | * reentered, there can be a deadlock - we would be holding a quota | |
1510 | * lock, and the commit would never complete if another thread had a | |
1511 | * transaction open and was blocking on the quota lock - a ranking | |
1512 | * violation. | |
1513 | * | |
dab291af | 1514 | * So what we do is to rely on the fact that jbd2_journal_stop/journal_start |
ac27a0ec DK |
1515 | * will _not_ run commit under these circumstances because handle->h_ref |
1516 | * is elevated. We'll still have enough credits for the tiny quotafile | |
1517 | * write. | |
1518 | */ | |
1519 | static int do_journal_get_write_access(handle_t *handle, | |
de9a55b8 | 1520 | struct buffer_head *bh) |
ac27a0ec DK |
1521 | { |
1522 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1523 | return 0; | |
617ba13b | 1524 | return ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
1525 | } |
1526 | ||
b9a4207d JK |
1527 | /* |
1528 | * Truncate blocks that were not used by write. We have to truncate the | |
1529 | * pagecache as well so that corresponding buffers get properly unmapped. | |
1530 | */ | |
1531 | static void ext4_truncate_failed_write(struct inode *inode) | |
1532 | { | |
1533 | truncate_inode_pages(inode->i_mapping, inode->i_size); | |
1534 | ext4_truncate(inode); | |
1535 | } | |
1536 | ||
bfc1af65 | 1537 | static int ext4_write_begin(struct file *file, struct address_space *mapping, |
de9a55b8 TT |
1538 | loff_t pos, unsigned len, unsigned flags, |
1539 | struct page **pagep, void **fsdata) | |
ac27a0ec | 1540 | { |
af5bc92d | 1541 | struct inode *inode = mapping->host; |
1938a150 | 1542 | int ret, needed_blocks; |
ac27a0ec DK |
1543 | handle_t *handle; |
1544 | int retries = 0; | |
af5bc92d | 1545 | struct page *page; |
de9a55b8 | 1546 | pgoff_t index; |
af5bc92d | 1547 | unsigned from, to; |
bfc1af65 | 1548 | |
9bffad1e | 1549 | trace_ext4_write_begin(inode, pos, len, flags); |
1938a150 AK |
1550 | /* |
1551 | * Reserve one block more for addition to orphan list in case | |
1552 | * we allocate blocks but write fails for some reason | |
1553 | */ | |
1554 | needed_blocks = ext4_writepage_trans_blocks(inode) + 1; | |
de9a55b8 | 1555 | index = pos >> PAGE_CACHE_SHIFT; |
af5bc92d TT |
1556 | from = pos & (PAGE_CACHE_SIZE - 1); |
1557 | to = from + len; | |
ac27a0ec DK |
1558 | |
1559 | retry: | |
af5bc92d TT |
1560 | handle = ext4_journal_start(inode, needed_blocks); |
1561 | if (IS_ERR(handle)) { | |
1562 | ret = PTR_ERR(handle); | |
1563 | goto out; | |
7479d2b9 | 1564 | } |
ac27a0ec | 1565 | |
ebd3610b JK |
1566 | /* We cannot recurse into the filesystem as the transaction is already |
1567 | * started */ | |
1568 | flags |= AOP_FLAG_NOFS; | |
1569 | ||
54566b2c | 1570 | page = grab_cache_page_write_begin(mapping, index, flags); |
cf108bca JK |
1571 | if (!page) { |
1572 | ext4_journal_stop(handle); | |
1573 | ret = -ENOMEM; | |
1574 | goto out; | |
1575 | } | |
1576 | *pagep = page; | |
1577 | ||
bfc1af65 | 1578 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, |
ebd3610b | 1579 | ext4_get_block); |
bfc1af65 NP |
1580 | |
1581 | if (!ret && ext4_should_journal_data(inode)) { | |
ac27a0ec DK |
1582 | ret = walk_page_buffers(handle, page_buffers(page), |
1583 | from, to, NULL, do_journal_get_write_access); | |
1584 | } | |
bfc1af65 NP |
1585 | |
1586 | if (ret) { | |
af5bc92d | 1587 | unlock_page(page); |
af5bc92d | 1588 | page_cache_release(page); |
ae4d5372 AK |
1589 | /* |
1590 | * block_write_begin may have instantiated a few blocks | |
1591 | * outside i_size. Trim these off again. Don't need | |
1592 | * i_size_read because we hold i_mutex. | |
1938a150 AK |
1593 | * |
1594 | * Add inode to orphan list in case we crash before | |
1595 | * truncate finishes | |
ae4d5372 | 1596 | */ |
ffacfa7a | 1597 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
1938a150 AK |
1598 | ext4_orphan_add(handle, inode); |
1599 | ||
1600 | ext4_journal_stop(handle); | |
1601 | if (pos + len > inode->i_size) { | |
b9a4207d | 1602 | ext4_truncate_failed_write(inode); |
de9a55b8 | 1603 | /* |
ffacfa7a | 1604 | * If truncate failed early the inode might |
1938a150 AK |
1605 | * still be on the orphan list; we need to |
1606 | * make sure the inode is removed from the | |
1607 | * orphan list in that case. | |
1608 | */ | |
1609 | if (inode->i_nlink) | |
1610 | ext4_orphan_del(NULL, inode); | |
1611 | } | |
bfc1af65 NP |
1612 | } |
1613 | ||
617ba13b | 1614 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
ac27a0ec | 1615 | goto retry; |
7479d2b9 | 1616 | out: |
ac27a0ec DK |
1617 | return ret; |
1618 | } | |
1619 | ||
bfc1af65 NP |
1620 | /* For write_end() in data=journal mode */ |
1621 | static int write_end_fn(handle_t *handle, struct buffer_head *bh) | |
ac27a0ec DK |
1622 | { |
1623 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1624 | return 0; | |
1625 | set_buffer_uptodate(bh); | |
0390131b | 1626 | return ext4_handle_dirty_metadata(handle, NULL, bh); |
ac27a0ec DK |
1627 | } |
1628 | ||
f8514083 | 1629 | static int ext4_generic_write_end(struct file *file, |
de9a55b8 TT |
1630 | struct address_space *mapping, |
1631 | loff_t pos, unsigned len, unsigned copied, | |
1632 | struct page *page, void *fsdata) | |
f8514083 AK |
1633 | { |
1634 | int i_size_changed = 0; | |
1635 | struct inode *inode = mapping->host; | |
1636 | handle_t *handle = ext4_journal_current_handle(); | |
1637 | ||
1638 | copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); | |
1639 | ||
1640 | /* | |
1641 | * No need to use i_size_read() here, the i_size | |
1642 | * cannot change under us because we hold i_mutex. | |
1643 | * | |
1644 | * But it's important to update i_size while still holding page lock: | |
1645 | * page writeout could otherwise come in and zero beyond i_size. | |
1646 | */ | |
1647 | if (pos + copied > inode->i_size) { | |
1648 | i_size_write(inode, pos + copied); | |
1649 | i_size_changed = 1; | |
1650 | } | |
1651 | ||
1652 | if (pos + copied > EXT4_I(inode)->i_disksize) { | |
1653 | /* We need to mark inode dirty even if | |
1654 | * new_i_size is less that inode->i_size | |
1655 | * bu greater than i_disksize.(hint delalloc) | |
1656 | */ | |
1657 | ext4_update_i_disksize(inode, (pos + copied)); | |
1658 | i_size_changed = 1; | |
1659 | } | |
1660 | unlock_page(page); | |
1661 | page_cache_release(page); | |
1662 | ||
1663 | /* | |
1664 | * Don't mark the inode dirty under page lock. First, it unnecessarily | |
1665 | * makes the holding time of page lock longer. Second, it forces lock | |
1666 | * ordering of page lock and transaction start for journaling | |
1667 | * filesystems. | |
1668 | */ | |
1669 | if (i_size_changed) | |
1670 | ext4_mark_inode_dirty(handle, inode); | |
1671 | ||
1672 | return copied; | |
1673 | } | |
1674 | ||
ac27a0ec DK |
1675 | /* |
1676 | * We need to pick up the new inode size which generic_commit_write gave us | |
1677 | * `file' can be NULL - eg, when called from page_symlink(). | |
1678 | * | |
617ba13b | 1679 | * ext4 never places buffers on inode->i_mapping->private_list. metadata |
ac27a0ec DK |
1680 | * buffers are managed internally. |
1681 | */ | |
bfc1af65 | 1682 | static int ext4_ordered_write_end(struct file *file, |
de9a55b8 TT |
1683 | struct address_space *mapping, |
1684 | loff_t pos, unsigned len, unsigned copied, | |
1685 | struct page *page, void *fsdata) | |
ac27a0ec | 1686 | { |
617ba13b | 1687 | handle_t *handle = ext4_journal_current_handle(); |
cf108bca | 1688 | struct inode *inode = mapping->host; |
ac27a0ec DK |
1689 | int ret = 0, ret2; |
1690 | ||
9bffad1e | 1691 | trace_ext4_ordered_write_end(inode, pos, len, copied); |
678aaf48 | 1692 | ret = ext4_jbd2_file_inode(handle, inode); |
ac27a0ec DK |
1693 | |
1694 | if (ret == 0) { | |
f8514083 | 1695 | ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, |
bfc1af65 | 1696 | page, fsdata); |
f8a87d89 | 1697 | copied = ret2; |
ffacfa7a | 1698 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1699 | /* if we have allocated more blocks and copied |
1700 | * less. We will have blocks allocated outside | |
1701 | * inode->i_size. So truncate them | |
1702 | */ | |
1703 | ext4_orphan_add(handle, inode); | |
f8a87d89 RK |
1704 | if (ret2 < 0) |
1705 | ret = ret2; | |
ac27a0ec | 1706 | } |
617ba13b | 1707 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1708 | if (!ret) |
1709 | ret = ret2; | |
bfc1af65 | 1710 | |
f8514083 | 1711 | if (pos + len > inode->i_size) { |
b9a4207d | 1712 | ext4_truncate_failed_write(inode); |
de9a55b8 | 1713 | /* |
ffacfa7a | 1714 | * If truncate failed early the inode might still be |
f8514083 AK |
1715 | * on the orphan list; we need to make sure the inode |
1716 | * is removed from the orphan list in that case. | |
1717 | */ | |
1718 | if (inode->i_nlink) | |
1719 | ext4_orphan_del(NULL, inode); | |
1720 | } | |
1721 | ||
1722 | ||
bfc1af65 | 1723 | return ret ? ret : copied; |
ac27a0ec DK |
1724 | } |
1725 | ||
bfc1af65 | 1726 | static int ext4_writeback_write_end(struct file *file, |
de9a55b8 TT |
1727 | struct address_space *mapping, |
1728 | loff_t pos, unsigned len, unsigned copied, | |
1729 | struct page *page, void *fsdata) | |
ac27a0ec | 1730 | { |
617ba13b | 1731 | handle_t *handle = ext4_journal_current_handle(); |
cf108bca | 1732 | struct inode *inode = mapping->host; |
ac27a0ec | 1733 | int ret = 0, ret2; |
ac27a0ec | 1734 | |
9bffad1e | 1735 | trace_ext4_writeback_write_end(inode, pos, len, copied); |
f8514083 | 1736 | ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, |
bfc1af65 | 1737 | page, fsdata); |
f8a87d89 | 1738 | copied = ret2; |
ffacfa7a | 1739 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1740 | /* if we have allocated more blocks and copied |
1741 | * less. We will have blocks allocated outside | |
1742 | * inode->i_size. So truncate them | |
1743 | */ | |
1744 | ext4_orphan_add(handle, inode); | |
1745 | ||
f8a87d89 RK |
1746 | if (ret2 < 0) |
1747 | ret = ret2; | |
ac27a0ec | 1748 | |
617ba13b | 1749 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1750 | if (!ret) |
1751 | ret = ret2; | |
bfc1af65 | 1752 | |
f8514083 | 1753 | if (pos + len > inode->i_size) { |
b9a4207d | 1754 | ext4_truncate_failed_write(inode); |
de9a55b8 | 1755 | /* |
ffacfa7a | 1756 | * If truncate failed early the inode might still be |
f8514083 AK |
1757 | * on the orphan list; we need to make sure the inode |
1758 | * is removed from the orphan list in that case. | |
1759 | */ | |
1760 | if (inode->i_nlink) | |
1761 | ext4_orphan_del(NULL, inode); | |
1762 | } | |
1763 | ||
bfc1af65 | 1764 | return ret ? ret : copied; |
ac27a0ec DK |
1765 | } |
1766 | ||
bfc1af65 | 1767 | static int ext4_journalled_write_end(struct file *file, |
de9a55b8 TT |
1768 | struct address_space *mapping, |
1769 | loff_t pos, unsigned len, unsigned copied, | |
1770 | struct page *page, void *fsdata) | |
ac27a0ec | 1771 | { |
617ba13b | 1772 | handle_t *handle = ext4_journal_current_handle(); |
bfc1af65 | 1773 | struct inode *inode = mapping->host; |
ac27a0ec DK |
1774 | int ret = 0, ret2; |
1775 | int partial = 0; | |
bfc1af65 | 1776 | unsigned from, to; |
cf17fea6 | 1777 | loff_t new_i_size; |
ac27a0ec | 1778 | |
9bffad1e | 1779 | trace_ext4_journalled_write_end(inode, pos, len, copied); |
bfc1af65 NP |
1780 | from = pos & (PAGE_CACHE_SIZE - 1); |
1781 | to = from + len; | |
1782 | ||
1783 | if (copied < len) { | |
1784 | if (!PageUptodate(page)) | |
1785 | copied = 0; | |
1786 | page_zero_new_buffers(page, from+copied, to); | |
1787 | } | |
ac27a0ec DK |
1788 | |
1789 | ret = walk_page_buffers(handle, page_buffers(page), from, | |
bfc1af65 | 1790 | to, &partial, write_end_fn); |
ac27a0ec DK |
1791 | if (!partial) |
1792 | SetPageUptodate(page); | |
cf17fea6 AK |
1793 | new_i_size = pos + copied; |
1794 | if (new_i_size > inode->i_size) | |
bfc1af65 | 1795 | i_size_write(inode, pos+copied); |
617ba13b | 1796 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; |
cf17fea6 AK |
1797 | if (new_i_size > EXT4_I(inode)->i_disksize) { |
1798 | ext4_update_i_disksize(inode, new_i_size); | |
617ba13b | 1799 | ret2 = ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
1800 | if (!ret) |
1801 | ret = ret2; | |
1802 | } | |
bfc1af65 | 1803 | |
cf108bca | 1804 | unlock_page(page); |
f8514083 | 1805 | page_cache_release(page); |
ffacfa7a | 1806 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1807 | /* if we have allocated more blocks and copied |
1808 | * less. We will have blocks allocated outside | |
1809 | * inode->i_size. So truncate them | |
1810 | */ | |
1811 | ext4_orphan_add(handle, inode); | |
1812 | ||
617ba13b | 1813 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1814 | if (!ret) |
1815 | ret = ret2; | |
f8514083 | 1816 | if (pos + len > inode->i_size) { |
b9a4207d | 1817 | ext4_truncate_failed_write(inode); |
de9a55b8 | 1818 | /* |
ffacfa7a | 1819 | * If truncate failed early the inode might still be |
f8514083 AK |
1820 | * on the orphan list; we need to make sure the inode |
1821 | * is removed from the orphan list in that case. | |
1822 | */ | |
1823 | if (inode->i_nlink) | |
1824 | ext4_orphan_del(NULL, inode); | |
1825 | } | |
bfc1af65 NP |
1826 | |
1827 | return ret ? ret : copied; | |
ac27a0ec | 1828 | } |
d2a17637 | 1829 | |
9d0be502 TT |
1830 | /* |
1831 | * Reserve a single block located at lblock | |
1832 | */ | |
1833 | static int ext4_da_reserve_space(struct inode *inode, sector_t lblock) | |
d2a17637 | 1834 | { |
030ba6bc | 1835 | int retries = 0; |
60e58e0f | 1836 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
0637c6f4 | 1837 | struct ext4_inode_info *ei = EXT4_I(inode); |
9d0be502 | 1838 | unsigned long md_needed, md_reserved; |
d2a17637 MC |
1839 | |
1840 | /* | |
1841 | * recalculate the amount of metadata blocks to reserve | |
1842 | * in order to allocate nrblocks | |
1843 | * worse case is one extent per block | |
1844 | */ | |
030ba6bc | 1845 | repeat: |
0637c6f4 TT |
1846 | spin_lock(&ei->i_block_reservation_lock); |
1847 | md_reserved = ei->i_reserved_meta_blocks; | |
9d0be502 | 1848 | md_needed = ext4_calc_metadata_amount(inode, lblock); |
0637c6f4 | 1849 | spin_unlock(&ei->i_block_reservation_lock); |
d2a17637 | 1850 | |
60e58e0f MC |
1851 | /* |
1852 | * Make quota reservation here to prevent quota overflow | |
1853 | * later. Real quota accounting is done at pages writeout | |
1854 | * time. | |
1855 | */ | |
1db91382 | 1856 | if (vfs_dq_reserve_block(inode, md_needed + 1)) |
60e58e0f | 1857 | return -EDQUOT; |
60e58e0f | 1858 | |
9d0be502 TT |
1859 | if (ext4_claim_free_blocks(sbi, md_needed + 1)) { |
1860 | vfs_dq_release_reservation_block(inode, md_needed + 1); | |
030ba6bc AK |
1861 | if (ext4_should_retry_alloc(inode->i_sb, &retries)) { |
1862 | yield(); | |
1863 | goto repeat; | |
1864 | } | |
d2a17637 MC |
1865 | return -ENOSPC; |
1866 | } | |
0637c6f4 | 1867 | spin_lock(&ei->i_block_reservation_lock); |
9d0be502 | 1868 | ei->i_reserved_data_blocks++; |
0637c6f4 TT |
1869 | ei->i_reserved_meta_blocks += md_needed; |
1870 | spin_unlock(&ei->i_block_reservation_lock); | |
39bc680a | 1871 | |
d2a17637 MC |
1872 | return 0; /* success */ |
1873 | } | |
1874 | ||
12219aea | 1875 | static void ext4_da_release_space(struct inode *inode, int to_free) |
d2a17637 MC |
1876 | { |
1877 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
0637c6f4 | 1878 | struct ext4_inode_info *ei = EXT4_I(inode); |
d2a17637 | 1879 | |
cd213226 MC |
1880 | if (!to_free) |
1881 | return; /* Nothing to release, exit */ | |
1882 | ||
d2a17637 | 1883 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
cd213226 | 1884 | |
0637c6f4 | 1885 | if (unlikely(to_free > ei->i_reserved_data_blocks)) { |
cd213226 | 1886 | /* |
0637c6f4 TT |
1887 | * if there aren't enough reserved blocks, then the |
1888 | * counter is messed up somewhere. Since this | |
1889 | * function is called from invalidate page, it's | |
1890 | * harmless to return without any action. | |
cd213226 | 1891 | */ |
0637c6f4 TT |
1892 | ext4_msg(inode->i_sb, KERN_NOTICE, "ext4_da_release_space: " |
1893 | "ino %lu, to_free %d with only %d reserved " | |
1894 | "data blocks\n", inode->i_ino, to_free, | |
1895 | ei->i_reserved_data_blocks); | |
1896 | WARN_ON(1); | |
1897 | to_free = ei->i_reserved_data_blocks; | |
cd213226 | 1898 | } |
0637c6f4 | 1899 | ei->i_reserved_data_blocks -= to_free; |
cd213226 | 1900 | |
0637c6f4 TT |
1901 | if (ei->i_reserved_data_blocks == 0) { |
1902 | /* | |
1903 | * We can release all of the reserved metadata blocks | |
1904 | * only when we have written all of the delayed | |
1905 | * allocation blocks. | |
1906 | */ | |
ee5f4d9c TT |
1907 | to_free += ei->i_reserved_meta_blocks; |
1908 | ei->i_reserved_meta_blocks = 0; | |
9d0be502 | 1909 | ei->i_da_metadata_calc_len = 0; |
0637c6f4 | 1910 | } |
d2a17637 | 1911 | |
0637c6f4 TT |
1912 | /* update fs dirty blocks counter */ |
1913 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, to_free); | |
d2a17637 | 1914 | |
d2a17637 | 1915 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
60e58e0f | 1916 | |
0637c6f4 | 1917 | vfs_dq_release_reservation_block(inode, to_free); |
d2a17637 MC |
1918 | } |
1919 | ||
1920 | static void ext4_da_page_release_reservation(struct page *page, | |
de9a55b8 | 1921 | unsigned long offset) |
d2a17637 MC |
1922 | { |
1923 | int to_release = 0; | |
1924 | struct buffer_head *head, *bh; | |
1925 | unsigned int curr_off = 0; | |
1926 | ||
1927 | head = page_buffers(page); | |
1928 | bh = head; | |
1929 | do { | |
1930 | unsigned int next_off = curr_off + bh->b_size; | |
1931 | ||
1932 | if ((offset <= curr_off) && (buffer_delay(bh))) { | |
1933 | to_release++; | |
1934 | clear_buffer_delay(bh); | |
1935 | } | |
1936 | curr_off = next_off; | |
1937 | } while ((bh = bh->b_this_page) != head); | |
12219aea | 1938 | ext4_da_release_space(page->mapping->host, to_release); |
d2a17637 | 1939 | } |
ac27a0ec | 1940 | |
64769240 AT |
1941 | /* |
1942 | * Delayed allocation stuff | |
1943 | */ | |
1944 | ||
64769240 AT |
1945 | /* |
1946 | * mpage_da_submit_io - walks through extent of pages and try to write | |
a1d6cc56 | 1947 | * them with writepage() call back |
64769240 AT |
1948 | * |
1949 | * @mpd->inode: inode | |
1950 | * @mpd->first_page: first page of the extent | |
1951 | * @mpd->next_page: page after the last page of the extent | |
64769240 AT |
1952 | * |
1953 | * By the time mpage_da_submit_io() is called we expect all blocks | |
1954 | * to be allocated. this may be wrong if allocation failed. | |
1955 | * | |
1956 | * As pages are already locked by write_cache_pages(), we can't use it | |
1957 | */ | |
1958 | static int mpage_da_submit_io(struct mpage_da_data *mpd) | |
1959 | { | |
22208ded | 1960 | long pages_skipped; |
791b7f08 AK |
1961 | struct pagevec pvec; |
1962 | unsigned long index, end; | |
1963 | int ret = 0, err, nr_pages, i; | |
1964 | struct inode *inode = mpd->inode; | |
1965 | struct address_space *mapping = inode->i_mapping; | |
64769240 AT |
1966 | |
1967 | BUG_ON(mpd->next_page <= mpd->first_page); | |
791b7f08 AK |
1968 | /* |
1969 | * We need to start from the first_page to the next_page - 1 | |
1970 | * to make sure we also write the mapped dirty buffer_heads. | |
8dc207c0 | 1971 | * If we look at mpd->b_blocknr we would only be looking |
791b7f08 AK |
1972 | * at the currently mapped buffer_heads. |
1973 | */ | |
64769240 AT |
1974 | index = mpd->first_page; |
1975 | end = mpd->next_page - 1; | |
1976 | ||
791b7f08 | 1977 | pagevec_init(&pvec, 0); |
64769240 | 1978 | while (index <= end) { |
791b7f08 | 1979 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); |
64769240 AT |
1980 | if (nr_pages == 0) |
1981 | break; | |
1982 | for (i = 0; i < nr_pages; i++) { | |
1983 | struct page *page = pvec.pages[i]; | |
1984 | ||
791b7f08 AK |
1985 | index = page->index; |
1986 | if (index > end) | |
1987 | break; | |
1988 | index++; | |
1989 | ||
1990 | BUG_ON(!PageLocked(page)); | |
1991 | BUG_ON(PageWriteback(page)); | |
1992 | ||
22208ded | 1993 | pages_skipped = mpd->wbc->pages_skipped; |
a1d6cc56 | 1994 | err = mapping->a_ops->writepage(page, mpd->wbc); |
22208ded AK |
1995 | if (!err && (pages_skipped == mpd->wbc->pages_skipped)) |
1996 | /* | |
1997 | * have successfully written the page | |
1998 | * without skipping the same | |
1999 | */ | |
a1d6cc56 | 2000 | mpd->pages_written++; |
64769240 AT |
2001 | /* |
2002 | * In error case, we have to continue because | |
2003 | * remaining pages are still locked | |
2004 | * XXX: unlock and re-dirty them? | |
2005 | */ | |
2006 | if (ret == 0) | |
2007 | ret = err; | |
2008 | } | |
2009 | pagevec_release(&pvec); | |
2010 | } | |
64769240 AT |
2011 | return ret; |
2012 | } | |
2013 | ||
2014 | /* | |
2015 | * mpage_put_bnr_to_bhs - walk blocks and assign them actual numbers | |
2016 | * | |
2017 | * @mpd->inode - inode to walk through | |
2018 | * @exbh->b_blocknr - first block on a disk | |
2019 | * @exbh->b_size - amount of space in bytes | |
2020 | * @logical - first logical block to start assignment with | |
2021 | * | |
2022 | * the function goes through all passed space and put actual disk | |
29fa89d0 | 2023 | * block numbers into buffer heads, dropping BH_Delay and BH_Unwritten |
64769240 AT |
2024 | */ |
2025 | static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical, | |
2026 | struct buffer_head *exbh) | |
2027 | { | |
2028 | struct inode *inode = mpd->inode; | |
2029 | struct address_space *mapping = inode->i_mapping; | |
2030 | int blocks = exbh->b_size >> inode->i_blkbits; | |
2031 | sector_t pblock = exbh->b_blocknr, cur_logical; | |
2032 | struct buffer_head *head, *bh; | |
a1d6cc56 | 2033 | pgoff_t index, end; |
64769240 AT |
2034 | struct pagevec pvec; |
2035 | int nr_pages, i; | |
2036 | ||
2037 | index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2038 | end = (logical + blocks - 1) >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2039 | cur_logical = index << (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2040 | ||
2041 | pagevec_init(&pvec, 0); | |
2042 | ||
2043 | while (index <= end) { | |
2044 | /* XXX: optimize tail */ | |
2045 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); | |
2046 | if (nr_pages == 0) | |
2047 | break; | |
2048 | for (i = 0; i < nr_pages; i++) { | |
2049 | struct page *page = pvec.pages[i]; | |
2050 | ||
2051 | index = page->index; | |
2052 | if (index > end) | |
2053 | break; | |
2054 | index++; | |
2055 | ||
2056 | BUG_ON(!PageLocked(page)); | |
2057 | BUG_ON(PageWriteback(page)); | |
2058 | BUG_ON(!page_has_buffers(page)); | |
2059 | ||
2060 | bh = page_buffers(page); | |
2061 | head = bh; | |
2062 | ||
2063 | /* skip blocks out of the range */ | |
2064 | do { | |
2065 | if (cur_logical >= logical) | |
2066 | break; | |
2067 | cur_logical++; | |
2068 | } while ((bh = bh->b_this_page) != head); | |
2069 | ||
2070 | do { | |
2071 | if (cur_logical >= logical + blocks) | |
2072 | break; | |
29fa89d0 AK |
2073 | |
2074 | if (buffer_delay(bh) || | |
2075 | buffer_unwritten(bh)) { | |
2076 | ||
2077 | BUG_ON(bh->b_bdev != inode->i_sb->s_bdev); | |
2078 | ||
2079 | if (buffer_delay(bh)) { | |
2080 | clear_buffer_delay(bh); | |
2081 | bh->b_blocknr = pblock; | |
2082 | } else { | |
2083 | /* | |
2084 | * unwritten already should have | |
2085 | * blocknr assigned. Verify that | |
2086 | */ | |
2087 | clear_buffer_unwritten(bh); | |
2088 | BUG_ON(bh->b_blocknr != pblock); | |
2089 | } | |
2090 | ||
61628a3f | 2091 | } else if (buffer_mapped(bh)) |
64769240 | 2092 | BUG_ON(bh->b_blocknr != pblock); |
64769240 AT |
2093 | |
2094 | cur_logical++; | |
2095 | pblock++; | |
2096 | } while ((bh = bh->b_this_page) != head); | |
2097 | } | |
2098 | pagevec_release(&pvec); | |
2099 | } | |
2100 | } | |
2101 | ||
2102 | ||
2103 | /* | |
2104 | * __unmap_underlying_blocks - just a helper function to unmap | |
2105 | * set of blocks described by @bh | |
2106 | */ | |
2107 | static inline void __unmap_underlying_blocks(struct inode *inode, | |
2108 | struct buffer_head *bh) | |
2109 | { | |
2110 | struct block_device *bdev = inode->i_sb->s_bdev; | |
2111 | int blocks, i; | |
2112 | ||
2113 | blocks = bh->b_size >> inode->i_blkbits; | |
2114 | for (i = 0; i < blocks; i++) | |
2115 | unmap_underlying_metadata(bdev, bh->b_blocknr + i); | |
2116 | } | |
2117 | ||
c4a0c46e AK |
2118 | static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd, |
2119 | sector_t logical, long blk_cnt) | |
2120 | { | |
2121 | int nr_pages, i; | |
2122 | pgoff_t index, end; | |
2123 | struct pagevec pvec; | |
2124 | struct inode *inode = mpd->inode; | |
2125 | struct address_space *mapping = inode->i_mapping; | |
2126 | ||
2127 | index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2128 | end = (logical + blk_cnt - 1) >> | |
2129 | (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2130 | while (index <= end) { | |
2131 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); | |
2132 | if (nr_pages == 0) | |
2133 | break; | |
2134 | for (i = 0; i < nr_pages; i++) { | |
2135 | struct page *page = pvec.pages[i]; | |
2136 | index = page->index; | |
2137 | if (index > end) | |
2138 | break; | |
2139 | index++; | |
2140 | ||
2141 | BUG_ON(!PageLocked(page)); | |
2142 | BUG_ON(PageWriteback(page)); | |
2143 | block_invalidatepage(page, 0); | |
2144 | ClearPageUptodate(page); | |
2145 | unlock_page(page); | |
2146 | } | |
2147 | } | |
2148 | return; | |
2149 | } | |
2150 | ||
df22291f AK |
2151 | static void ext4_print_free_blocks(struct inode *inode) |
2152 | { | |
2153 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
1693918e TT |
2154 | printk(KERN_CRIT "Total free blocks count %lld\n", |
2155 | ext4_count_free_blocks(inode->i_sb)); | |
2156 | printk(KERN_CRIT "Free/Dirty block details\n"); | |
2157 | printk(KERN_CRIT "free_blocks=%lld\n", | |
2158 | (long long) percpu_counter_sum(&sbi->s_freeblocks_counter)); | |
2159 | printk(KERN_CRIT "dirty_blocks=%lld\n", | |
2160 | (long long) percpu_counter_sum(&sbi->s_dirtyblocks_counter)); | |
2161 | printk(KERN_CRIT "Block reservation details\n"); | |
2162 | printk(KERN_CRIT "i_reserved_data_blocks=%u\n", | |
2163 | EXT4_I(inode)->i_reserved_data_blocks); | |
2164 | printk(KERN_CRIT "i_reserved_meta_blocks=%u\n", | |
2165 | EXT4_I(inode)->i_reserved_meta_blocks); | |
df22291f AK |
2166 | return; |
2167 | } | |
2168 | ||
64769240 AT |
2169 | /* |
2170 | * mpage_da_map_blocks - go through given space | |
2171 | * | |
8dc207c0 | 2172 | * @mpd - bh describing space |
64769240 AT |
2173 | * |
2174 | * The function skips space we know is already mapped to disk blocks. | |
2175 | * | |
64769240 | 2176 | */ |
ed5bde0b | 2177 | static int mpage_da_map_blocks(struct mpage_da_data *mpd) |
64769240 | 2178 | { |
2ac3b6e0 | 2179 | int err, blks, get_blocks_flags; |
030ba6bc | 2180 | struct buffer_head new; |
2fa3cdfb TT |
2181 | sector_t next = mpd->b_blocknr; |
2182 | unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits; | |
2183 | loff_t disksize = EXT4_I(mpd->inode)->i_disksize; | |
2184 | handle_t *handle = NULL; | |
64769240 AT |
2185 | |
2186 | /* | |
2187 | * We consider only non-mapped and non-allocated blocks | |
2188 | */ | |
8dc207c0 | 2189 | if ((mpd->b_state & (1 << BH_Mapped)) && |
29fa89d0 AK |
2190 | !(mpd->b_state & (1 << BH_Delay)) && |
2191 | !(mpd->b_state & (1 << BH_Unwritten))) | |
c4a0c46e | 2192 | return 0; |
2fa3cdfb TT |
2193 | |
2194 | /* | |
2195 | * If we didn't accumulate anything to write simply return | |
2196 | */ | |
2197 | if (!mpd->b_size) | |
2198 | return 0; | |
2199 | ||
2200 | handle = ext4_journal_current_handle(); | |
2201 | BUG_ON(!handle); | |
2202 | ||
79ffab34 | 2203 | /* |
2ac3b6e0 TT |
2204 | * Call ext4_get_blocks() to allocate any delayed allocation |
2205 | * blocks, or to convert an uninitialized extent to be | |
2206 | * initialized (in the case where we have written into | |
2207 | * one or more preallocated blocks). | |
2208 | * | |
2209 | * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to | |
2210 | * indicate that we are on the delayed allocation path. This | |
2211 | * affects functions in many different parts of the allocation | |
2212 | * call path. This flag exists primarily because we don't | |
2213 | * want to change *many* call functions, so ext4_get_blocks() | |
2214 | * will set the magic i_delalloc_reserved_flag once the | |
2215 | * inode's allocation semaphore is taken. | |
2216 | * | |
2217 | * If the blocks in questions were delalloc blocks, set | |
2218 | * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting | |
2219 | * variables are updated after the blocks have been allocated. | |
79ffab34 | 2220 | */ |
2ac3b6e0 | 2221 | new.b_state = 0; |
1296cc85 | 2222 | get_blocks_flags = EXT4_GET_BLOCKS_CREATE; |
2ac3b6e0 | 2223 | if (mpd->b_state & (1 << BH_Delay)) |
1296cc85 AK |
2224 | get_blocks_flags |= EXT4_GET_BLOCKS_DELALLOC_RESERVE; |
2225 | ||
2fa3cdfb | 2226 | blks = ext4_get_blocks(handle, mpd->inode, next, max_blocks, |
2ac3b6e0 | 2227 | &new, get_blocks_flags); |
2fa3cdfb TT |
2228 | if (blks < 0) { |
2229 | err = blks; | |
ed5bde0b TT |
2230 | /* |
2231 | * If get block returns with error we simply | |
2232 | * return. Later writepage will redirty the page and | |
2233 | * writepages will find the dirty page again | |
c4a0c46e AK |
2234 | */ |
2235 | if (err == -EAGAIN) | |
2236 | return 0; | |
df22291f AK |
2237 | |
2238 | if (err == -ENOSPC && | |
ed5bde0b | 2239 | ext4_count_free_blocks(mpd->inode->i_sb)) { |
df22291f AK |
2240 | mpd->retval = err; |
2241 | return 0; | |
2242 | } | |
2243 | ||
c4a0c46e | 2244 | /* |
ed5bde0b TT |
2245 | * get block failure will cause us to loop in |
2246 | * writepages, because a_ops->writepage won't be able | |
2247 | * to make progress. The page will be redirtied by | |
2248 | * writepage and writepages will again try to write | |
2249 | * the same. | |
c4a0c46e | 2250 | */ |
1693918e TT |
2251 | ext4_msg(mpd->inode->i_sb, KERN_CRIT, |
2252 | "delayed block allocation failed for inode %lu at " | |
2253 | "logical offset %llu with max blocks %zd with " | |
2254 | "error %d\n", mpd->inode->i_ino, | |
2255 | (unsigned long long) next, | |
2256 | mpd->b_size >> mpd->inode->i_blkbits, err); | |
2257 | printk(KERN_CRIT "This should not happen!! " | |
2258 | "Data will be lost\n"); | |
030ba6bc | 2259 | if (err == -ENOSPC) { |
df22291f | 2260 | ext4_print_free_blocks(mpd->inode); |
030ba6bc | 2261 | } |
2fa3cdfb | 2262 | /* invalidate all the pages */ |
c4a0c46e | 2263 | ext4_da_block_invalidatepages(mpd, next, |
8dc207c0 | 2264 | mpd->b_size >> mpd->inode->i_blkbits); |
c4a0c46e AK |
2265 | return err; |
2266 | } | |
2fa3cdfb TT |
2267 | BUG_ON(blks == 0); |
2268 | ||
2269 | new.b_size = (blks << mpd->inode->i_blkbits); | |
64769240 | 2270 | |
a1d6cc56 AK |
2271 | if (buffer_new(&new)) |
2272 | __unmap_underlying_blocks(mpd->inode, &new); | |
64769240 | 2273 | |
a1d6cc56 AK |
2274 | /* |
2275 | * If blocks are delayed marked, we need to | |
2276 | * put actual blocknr and drop delayed bit | |
2277 | */ | |
8dc207c0 TT |
2278 | if ((mpd->b_state & (1 << BH_Delay)) || |
2279 | (mpd->b_state & (1 << BH_Unwritten))) | |
a1d6cc56 | 2280 | mpage_put_bnr_to_bhs(mpd, next, &new); |
64769240 | 2281 | |
2fa3cdfb TT |
2282 | if (ext4_should_order_data(mpd->inode)) { |
2283 | err = ext4_jbd2_file_inode(handle, mpd->inode); | |
2284 | if (err) | |
2285 | return err; | |
2286 | } | |
2287 | ||
2288 | /* | |
03f5d8bc | 2289 | * Update on-disk size along with block allocation. |
2fa3cdfb TT |
2290 | */ |
2291 | disksize = ((loff_t) next + blks) << mpd->inode->i_blkbits; | |
2292 | if (disksize > i_size_read(mpd->inode)) | |
2293 | disksize = i_size_read(mpd->inode); | |
2294 | if (disksize > EXT4_I(mpd->inode)->i_disksize) { | |
2295 | ext4_update_i_disksize(mpd->inode, disksize); | |
2296 | return ext4_mark_inode_dirty(handle, mpd->inode); | |
2297 | } | |
2298 | ||
c4a0c46e | 2299 | return 0; |
64769240 AT |
2300 | } |
2301 | ||
bf068ee2 AK |
2302 | #define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \ |
2303 | (1 << BH_Delay) | (1 << BH_Unwritten)) | |
64769240 AT |
2304 | |
2305 | /* | |
2306 | * mpage_add_bh_to_extent - try to add one more block to extent of blocks | |
2307 | * | |
2308 | * @mpd->lbh - extent of blocks | |
2309 | * @logical - logical number of the block in the file | |
2310 | * @bh - bh of the block (used to access block's state) | |
2311 | * | |
2312 | * the function is used to collect contig. blocks in same state | |
2313 | */ | |
2314 | static void mpage_add_bh_to_extent(struct mpage_da_data *mpd, | |
8dc207c0 TT |
2315 | sector_t logical, size_t b_size, |
2316 | unsigned long b_state) | |
64769240 | 2317 | { |
64769240 | 2318 | sector_t next; |
8dc207c0 | 2319 | int nrblocks = mpd->b_size >> mpd->inode->i_blkbits; |
64769240 | 2320 | |
525f4ed8 MC |
2321 | /* check if thereserved journal credits might overflow */ |
2322 | if (!(EXT4_I(mpd->inode)->i_flags & EXT4_EXTENTS_FL)) { | |
2323 | if (nrblocks >= EXT4_MAX_TRANS_DATA) { | |
2324 | /* | |
2325 | * With non-extent format we are limited by the journal | |
2326 | * credit available. Total credit needed to insert | |
2327 | * nrblocks contiguous blocks is dependent on the | |
2328 | * nrblocks. So limit nrblocks. | |
2329 | */ | |
2330 | goto flush_it; | |
2331 | } else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) > | |
2332 | EXT4_MAX_TRANS_DATA) { | |
2333 | /* | |
2334 | * Adding the new buffer_head would make it cross the | |
2335 | * allowed limit for which we have journal credit | |
2336 | * reserved. So limit the new bh->b_size | |
2337 | */ | |
2338 | b_size = (EXT4_MAX_TRANS_DATA - nrblocks) << | |
2339 | mpd->inode->i_blkbits; | |
2340 | /* we will do mpage_da_submit_io in the next loop */ | |
2341 | } | |
2342 | } | |
64769240 AT |
2343 | /* |
2344 | * First block in the extent | |
2345 | */ | |
8dc207c0 TT |
2346 | if (mpd->b_size == 0) { |
2347 | mpd->b_blocknr = logical; | |
2348 | mpd->b_size = b_size; | |
2349 | mpd->b_state = b_state & BH_FLAGS; | |
64769240 AT |
2350 | return; |
2351 | } | |
2352 | ||
8dc207c0 | 2353 | next = mpd->b_blocknr + nrblocks; |
64769240 AT |
2354 | /* |
2355 | * Can we merge the block to our big extent? | |
2356 | */ | |
8dc207c0 TT |
2357 | if (logical == next && (b_state & BH_FLAGS) == mpd->b_state) { |
2358 | mpd->b_size += b_size; | |
64769240 AT |
2359 | return; |
2360 | } | |
2361 | ||
525f4ed8 | 2362 | flush_it: |
64769240 AT |
2363 | /* |
2364 | * We couldn't merge the block to our extent, so we | |
2365 | * need to flush current extent and start new one | |
2366 | */ | |
c4a0c46e AK |
2367 | if (mpage_da_map_blocks(mpd) == 0) |
2368 | mpage_da_submit_io(mpd); | |
a1d6cc56 AK |
2369 | mpd->io_done = 1; |
2370 | return; | |
64769240 AT |
2371 | } |
2372 | ||
c364b22c | 2373 | static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh) |
29fa89d0 | 2374 | { |
c364b22c | 2375 | return (buffer_delay(bh) || buffer_unwritten(bh)) && buffer_dirty(bh); |
29fa89d0 AK |
2376 | } |
2377 | ||
64769240 AT |
2378 | /* |
2379 | * __mpage_da_writepage - finds extent of pages and blocks | |
2380 | * | |
2381 | * @page: page to consider | |
2382 | * @wbc: not used, we just follow rules | |
2383 | * @data: context | |
2384 | * | |
2385 | * The function finds extents of pages and scan them for all blocks. | |
2386 | */ | |
2387 | static int __mpage_da_writepage(struct page *page, | |
2388 | struct writeback_control *wbc, void *data) | |
2389 | { | |
2390 | struct mpage_da_data *mpd = data; | |
2391 | struct inode *inode = mpd->inode; | |
8dc207c0 | 2392 | struct buffer_head *bh, *head; |
64769240 AT |
2393 | sector_t logical; |
2394 | ||
a1d6cc56 AK |
2395 | if (mpd->io_done) { |
2396 | /* | |
2397 | * Rest of the page in the page_vec | |
2398 | * redirty then and skip then. We will | |
fd589a8f | 2399 | * try to write them again after |
a1d6cc56 AK |
2400 | * starting a new transaction |
2401 | */ | |
2402 | redirty_page_for_writepage(wbc, page); | |
2403 | unlock_page(page); | |
2404 | return MPAGE_DA_EXTENT_TAIL; | |
2405 | } | |
64769240 AT |
2406 | /* |
2407 | * Can we merge this page to current extent? | |
2408 | */ | |
2409 | if (mpd->next_page != page->index) { | |
2410 | /* | |
2411 | * Nope, we can't. So, we map non-allocated blocks | |
a1d6cc56 | 2412 | * and start IO on them using writepage() |
64769240 AT |
2413 | */ |
2414 | if (mpd->next_page != mpd->first_page) { | |
c4a0c46e AK |
2415 | if (mpage_da_map_blocks(mpd) == 0) |
2416 | mpage_da_submit_io(mpd); | |
a1d6cc56 AK |
2417 | /* |
2418 | * skip rest of the page in the page_vec | |
2419 | */ | |
2420 | mpd->io_done = 1; | |
2421 | redirty_page_for_writepage(wbc, page); | |
2422 | unlock_page(page); | |
2423 | return MPAGE_DA_EXTENT_TAIL; | |
64769240 AT |
2424 | } |
2425 | ||
2426 | /* | |
2427 | * Start next extent of pages ... | |
2428 | */ | |
2429 | mpd->first_page = page->index; | |
2430 | ||
2431 | /* | |
2432 | * ... and blocks | |
2433 | */ | |
8dc207c0 TT |
2434 | mpd->b_size = 0; |
2435 | mpd->b_state = 0; | |
2436 | mpd->b_blocknr = 0; | |
64769240 AT |
2437 | } |
2438 | ||
2439 | mpd->next_page = page->index + 1; | |
2440 | logical = (sector_t) page->index << | |
2441 | (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2442 | ||
2443 | if (!page_has_buffers(page)) { | |
8dc207c0 TT |
2444 | mpage_add_bh_to_extent(mpd, logical, PAGE_CACHE_SIZE, |
2445 | (1 << BH_Dirty) | (1 << BH_Uptodate)); | |
a1d6cc56 AK |
2446 | if (mpd->io_done) |
2447 | return MPAGE_DA_EXTENT_TAIL; | |
64769240 AT |
2448 | } else { |
2449 | /* | |
2450 | * Page with regular buffer heads, just add all dirty ones | |
2451 | */ | |
2452 | head = page_buffers(page); | |
2453 | bh = head; | |
2454 | do { | |
2455 | BUG_ON(buffer_locked(bh)); | |
791b7f08 AK |
2456 | /* |
2457 | * We need to try to allocate | |
2458 | * unmapped blocks in the same page. | |
2459 | * Otherwise we won't make progress | |
43ce1d23 | 2460 | * with the page in ext4_writepage |
791b7f08 | 2461 | */ |
c364b22c | 2462 | if (ext4_bh_delay_or_unwritten(NULL, bh)) { |
8dc207c0 TT |
2463 | mpage_add_bh_to_extent(mpd, logical, |
2464 | bh->b_size, | |
2465 | bh->b_state); | |
a1d6cc56 AK |
2466 | if (mpd->io_done) |
2467 | return MPAGE_DA_EXTENT_TAIL; | |
791b7f08 AK |
2468 | } else if (buffer_dirty(bh) && (buffer_mapped(bh))) { |
2469 | /* | |
2470 | * mapped dirty buffer. We need to update | |
2471 | * the b_state because we look at | |
2472 | * b_state in mpage_da_map_blocks. We don't | |
2473 | * update b_size because if we find an | |
2474 | * unmapped buffer_head later we need to | |
2475 | * use the b_state flag of that buffer_head. | |
2476 | */ | |
8dc207c0 TT |
2477 | if (mpd->b_size == 0) |
2478 | mpd->b_state = bh->b_state & BH_FLAGS; | |
a1d6cc56 | 2479 | } |
64769240 AT |
2480 | logical++; |
2481 | } while ((bh = bh->b_this_page) != head); | |
2482 | } | |
2483 | ||
2484 | return 0; | |
2485 | } | |
2486 | ||
64769240 | 2487 | /* |
b920c755 TT |
2488 | * This is a special get_blocks_t callback which is used by |
2489 | * ext4_da_write_begin(). It will either return mapped block or | |
2490 | * reserve space for a single block. | |
29fa89d0 AK |
2491 | * |
2492 | * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set. | |
2493 | * We also have b_blocknr = -1 and b_bdev initialized properly | |
2494 | * | |
2495 | * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set. | |
2496 | * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev | |
2497 | * initialized properly. | |
64769240 AT |
2498 | */ |
2499 | static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock, | |
2500 | struct buffer_head *bh_result, int create) | |
2501 | { | |
2502 | int ret = 0; | |
33b9817e AK |
2503 | sector_t invalid_block = ~((sector_t) 0xffff); |
2504 | ||
2505 | if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es)) | |
2506 | invalid_block = ~0; | |
64769240 AT |
2507 | |
2508 | BUG_ON(create == 0); | |
2509 | BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); | |
2510 | ||
2511 | /* | |
2512 | * first, we need to know whether the block is allocated already | |
2513 | * preallocated blocks are unmapped but should treated | |
2514 | * the same as allocated blocks. | |
2515 | */ | |
c2177057 | 2516 | ret = ext4_get_blocks(NULL, inode, iblock, 1, bh_result, 0); |
d2a17637 MC |
2517 | if ((ret == 0) && !buffer_delay(bh_result)) { |
2518 | /* the block isn't (pre)allocated yet, let's reserve space */ | |
64769240 AT |
2519 | /* |
2520 | * XXX: __block_prepare_write() unmaps passed block, | |
2521 | * is it OK? | |
2522 | */ | |
9d0be502 | 2523 | ret = ext4_da_reserve_space(inode, iblock); |
d2a17637 MC |
2524 | if (ret) |
2525 | /* not enough space to reserve */ | |
2526 | return ret; | |
2527 | ||
33b9817e | 2528 | map_bh(bh_result, inode->i_sb, invalid_block); |
64769240 AT |
2529 | set_buffer_new(bh_result); |
2530 | set_buffer_delay(bh_result); | |
2531 | } else if (ret > 0) { | |
2532 | bh_result->b_size = (ret << inode->i_blkbits); | |
29fa89d0 AK |
2533 | if (buffer_unwritten(bh_result)) { |
2534 | /* A delayed write to unwritten bh should | |
2535 | * be marked new and mapped. Mapped ensures | |
2536 | * that we don't do get_block multiple times | |
2537 | * when we write to the same offset and new | |
2538 | * ensures that we do proper zero out for | |
2539 | * partial write. | |
2540 | */ | |
9c1ee184 | 2541 | set_buffer_new(bh_result); |
29fa89d0 AK |
2542 | set_buffer_mapped(bh_result); |
2543 | } | |
64769240 AT |
2544 | ret = 0; |
2545 | } | |
2546 | ||
2547 | return ret; | |
2548 | } | |
61628a3f | 2549 | |
b920c755 TT |
2550 | /* |
2551 | * This function is used as a standard get_block_t calback function | |
2552 | * when there is no desire to allocate any blocks. It is used as a | |
2553 | * callback function for block_prepare_write(), nobh_writepage(), and | |
2554 | * block_write_full_page(). These functions should only try to map a | |
2555 | * single block at a time. | |
2556 | * | |
2557 | * Since this function doesn't do block allocations even if the caller | |
2558 | * requests it by passing in create=1, it is critically important that | |
2559 | * any caller checks to make sure that any buffer heads are returned | |
2560 | * by this function are either all already mapped or marked for | |
2561 | * delayed allocation before calling nobh_writepage() or | |
2562 | * block_write_full_page(). Otherwise, b_blocknr could be left | |
2563 | * unitialized, and the page write functions will be taken by | |
2564 | * surprise. | |
2565 | */ | |
2566 | static int noalloc_get_block_write(struct inode *inode, sector_t iblock, | |
f0e6c985 AK |
2567 | struct buffer_head *bh_result, int create) |
2568 | { | |
2569 | int ret = 0; | |
2570 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; | |
2571 | ||
a2dc52b5 TT |
2572 | BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); |
2573 | ||
f0e6c985 AK |
2574 | /* |
2575 | * we don't want to do block allocation in writepage | |
2576 | * so call get_block_wrap with create = 0 | |
2577 | */ | |
c2177057 | 2578 | ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0); |
f0e6c985 AK |
2579 | if (ret > 0) { |
2580 | bh_result->b_size = (ret << inode->i_blkbits); | |
2581 | ret = 0; | |
2582 | } | |
2583 | return ret; | |
61628a3f MC |
2584 | } |
2585 | ||
62e086be AK |
2586 | static int bget_one(handle_t *handle, struct buffer_head *bh) |
2587 | { | |
2588 | get_bh(bh); | |
2589 | return 0; | |
2590 | } | |
2591 | ||
2592 | static int bput_one(handle_t *handle, struct buffer_head *bh) | |
2593 | { | |
2594 | put_bh(bh); | |
2595 | return 0; | |
2596 | } | |
2597 | ||
2598 | static int __ext4_journalled_writepage(struct page *page, | |
62e086be AK |
2599 | unsigned int len) |
2600 | { | |
2601 | struct address_space *mapping = page->mapping; | |
2602 | struct inode *inode = mapping->host; | |
2603 | struct buffer_head *page_bufs; | |
2604 | handle_t *handle = NULL; | |
2605 | int ret = 0; | |
2606 | int err; | |
2607 | ||
2608 | page_bufs = page_buffers(page); | |
2609 | BUG_ON(!page_bufs); | |
2610 | walk_page_buffers(handle, page_bufs, 0, len, NULL, bget_one); | |
2611 | /* As soon as we unlock the page, it can go away, but we have | |
2612 | * references to buffers so we are safe */ | |
2613 | unlock_page(page); | |
2614 | ||
2615 | handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode)); | |
2616 | if (IS_ERR(handle)) { | |
2617 | ret = PTR_ERR(handle); | |
2618 | goto out; | |
2619 | } | |
2620 | ||
2621 | ret = walk_page_buffers(handle, page_bufs, 0, len, NULL, | |
2622 | do_journal_get_write_access); | |
2623 | ||
2624 | err = walk_page_buffers(handle, page_bufs, 0, len, NULL, | |
2625 | write_end_fn); | |
2626 | if (ret == 0) | |
2627 | ret = err; | |
2628 | err = ext4_journal_stop(handle); | |
2629 | if (!ret) | |
2630 | ret = err; | |
2631 | ||
2632 | walk_page_buffers(handle, page_bufs, 0, len, NULL, bput_one); | |
2633 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; | |
2634 | out: | |
2635 | return ret; | |
2636 | } | |
2637 | ||
61628a3f | 2638 | /* |
43ce1d23 AK |
2639 | * Note that we don't need to start a transaction unless we're journaling data |
2640 | * because we should have holes filled from ext4_page_mkwrite(). We even don't | |
2641 | * need to file the inode to the transaction's list in ordered mode because if | |
2642 | * we are writing back data added by write(), the inode is already there and if | |
2643 | * we are writing back data modified via mmap(), noone guarantees in which | |
2644 | * transaction the data will hit the disk. In case we are journaling data, we | |
2645 | * cannot start transaction directly because transaction start ranks above page | |
2646 | * lock so we have to do some magic. | |
2647 | * | |
b920c755 TT |
2648 | * This function can get called via... |
2649 | * - ext4_da_writepages after taking page lock (have journal handle) | |
2650 | * - journal_submit_inode_data_buffers (no journal handle) | |
2651 | * - shrink_page_list via pdflush (no journal handle) | |
2652 | * - grab_page_cache when doing write_begin (have journal handle) | |
43ce1d23 AK |
2653 | * |
2654 | * We don't do any block allocation in this function. If we have page with | |
2655 | * multiple blocks we need to write those buffer_heads that are mapped. This | |
2656 | * is important for mmaped based write. So if we do with blocksize 1K | |
2657 | * truncate(f, 1024); | |
2658 | * a = mmap(f, 0, 4096); | |
2659 | * a[0] = 'a'; | |
2660 | * truncate(f, 4096); | |
2661 | * we have in the page first buffer_head mapped via page_mkwrite call back | |
2662 | * but other bufer_heads would be unmapped but dirty(dirty done via the | |
2663 | * do_wp_page). So writepage should write the first block. If we modify | |
2664 | * the mmap area beyond 1024 we will again get a page_fault and the | |
2665 | * page_mkwrite callback will do the block allocation and mark the | |
2666 | * buffer_heads mapped. | |
2667 | * | |
2668 | * We redirty the page if we have any buffer_heads that is either delay or | |
2669 | * unwritten in the page. | |
2670 | * | |
2671 | * We can get recursively called as show below. | |
2672 | * | |
2673 | * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() -> | |
2674 | * ext4_writepage() | |
2675 | * | |
2676 | * But since we don't do any block allocation we should not deadlock. | |
2677 | * Page also have the dirty flag cleared so we don't get recurive page_lock. | |
61628a3f | 2678 | */ |
43ce1d23 | 2679 | static int ext4_writepage(struct page *page, |
62e086be | 2680 | struct writeback_control *wbc) |
64769240 | 2681 | { |
64769240 | 2682 | int ret = 0; |
61628a3f | 2683 | loff_t size; |
498e5f24 | 2684 | unsigned int len; |
61628a3f MC |
2685 | struct buffer_head *page_bufs; |
2686 | struct inode *inode = page->mapping->host; | |
2687 | ||
43ce1d23 | 2688 | trace_ext4_writepage(inode, page); |
f0e6c985 AK |
2689 | size = i_size_read(inode); |
2690 | if (page->index == size >> PAGE_CACHE_SHIFT) | |
2691 | len = size & ~PAGE_CACHE_MASK; | |
2692 | else | |
2693 | len = PAGE_CACHE_SIZE; | |
64769240 | 2694 | |
f0e6c985 | 2695 | if (page_has_buffers(page)) { |
61628a3f | 2696 | page_bufs = page_buffers(page); |
f0e6c985 | 2697 | if (walk_page_buffers(NULL, page_bufs, 0, len, NULL, |
c364b22c | 2698 | ext4_bh_delay_or_unwritten)) { |
61628a3f | 2699 | /* |
f0e6c985 AK |
2700 | * We don't want to do block allocation |
2701 | * So redirty the page and return | |
cd1aac32 AK |
2702 | * We may reach here when we do a journal commit |
2703 | * via journal_submit_inode_data_buffers. | |
2704 | * If we don't have mapping block we just ignore | |
f0e6c985 AK |
2705 | * them. We can also reach here via shrink_page_list |
2706 | */ | |
2707 | redirty_page_for_writepage(wbc, page); | |
2708 | unlock_page(page); | |
2709 | return 0; | |
2710 | } | |
2711 | } else { | |
2712 | /* | |
2713 | * The test for page_has_buffers() is subtle: | |
2714 | * We know the page is dirty but it lost buffers. That means | |
2715 | * that at some moment in time after write_begin()/write_end() | |
2716 | * has been called all buffers have been clean and thus they | |
2717 | * must have been written at least once. So they are all | |
2718 | * mapped and we can happily proceed with mapping them | |
2719 | * and writing the page. | |
2720 | * | |
2721 | * Try to initialize the buffer_heads and check whether | |
2722 | * all are mapped and non delay. We don't want to | |
2723 | * do block allocation here. | |
2724 | */ | |
b767e78a | 2725 | ret = block_prepare_write(page, 0, len, |
b920c755 | 2726 | noalloc_get_block_write); |
f0e6c985 AK |
2727 | if (!ret) { |
2728 | page_bufs = page_buffers(page); | |
2729 | /* check whether all are mapped and non delay */ | |
2730 | if (walk_page_buffers(NULL, page_bufs, 0, len, NULL, | |
c364b22c | 2731 | ext4_bh_delay_or_unwritten)) { |
f0e6c985 AK |
2732 | redirty_page_for_writepage(wbc, page); |
2733 | unlock_page(page); | |
2734 | return 0; | |
2735 | } | |
2736 | } else { | |
2737 | /* | |
2738 | * We can't do block allocation here | |
2739 | * so just redity the page and unlock | |
2740 | * and return | |
61628a3f | 2741 | */ |
61628a3f MC |
2742 | redirty_page_for_writepage(wbc, page); |
2743 | unlock_page(page); | |
2744 | return 0; | |
2745 | } | |
ed9b3e33 | 2746 | /* now mark the buffer_heads as dirty and uptodate */ |
b767e78a | 2747 | block_commit_write(page, 0, len); |
64769240 AT |
2748 | } |
2749 | ||
43ce1d23 AK |
2750 | if (PageChecked(page) && ext4_should_journal_data(inode)) { |
2751 | /* | |
2752 | * It's mmapped pagecache. Add buffers and journal it. There | |
2753 | * doesn't seem much point in redirtying the page here. | |
2754 | */ | |
2755 | ClearPageChecked(page); | |
3f0ca309 | 2756 | return __ext4_journalled_writepage(page, len); |
43ce1d23 AK |
2757 | } |
2758 | ||
64769240 | 2759 | if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) |
b920c755 | 2760 | ret = nobh_writepage(page, noalloc_get_block_write, wbc); |
64769240 | 2761 | else |
b920c755 TT |
2762 | ret = block_write_full_page(page, noalloc_get_block_write, |
2763 | wbc); | |
64769240 | 2764 | |
64769240 AT |
2765 | return ret; |
2766 | } | |
2767 | ||
61628a3f | 2768 | /* |
525f4ed8 MC |
2769 | * This is called via ext4_da_writepages() to |
2770 | * calulate the total number of credits to reserve to fit | |
2771 | * a single extent allocation into a single transaction, | |
2772 | * ext4_da_writpeages() will loop calling this before | |
2773 | * the block allocation. | |
61628a3f | 2774 | */ |
525f4ed8 MC |
2775 | |
2776 | static int ext4_da_writepages_trans_blocks(struct inode *inode) | |
2777 | { | |
2778 | int max_blocks = EXT4_I(inode)->i_reserved_data_blocks; | |
2779 | ||
2780 | /* | |
2781 | * With non-extent format the journal credit needed to | |
2782 | * insert nrblocks contiguous block is dependent on | |
2783 | * number of contiguous block. So we will limit | |
2784 | * number of contiguous block to a sane value | |
2785 | */ | |
30c6e07a | 2786 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) && |
525f4ed8 MC |
2787 | (max_blocks > EXT4_MAX_TRANS_DATA)) |
2788 | max_blocks = EXT4_MAX_TRANS_DATA; | |
2789 | ||
2790 | return ext4_chunk_trans_blocks(inode, max_blocks); | |
2791 | } | |
61628a3f | 2792 | |
64769240 | 2793 | static int ext4_da_writepages(struct address_space *mapping, |
a1d6cc56 | 2794 | struct writeback_control *wbc) |
64769240 | 2795 | { |
22208ded AK |
2796 | pgoff_t index; |
2797 | int range_whole = 0; | |
61628a3f | 2798 | handle_t *handle = NULL; |
df22291f | 2799 | struct mpage_da_data mpd; |
5e745b04 | 2800 | struct inode *inode = mapping->host; |
22208ded | 2801 | int no_nrwrite_index_update; |
498e5f24 TT |
2802 | int pages_written = 0; |
2803 | long pages_skipped; | |
55138e0b | 2804 | unsigned int max_pages; |
2acf2c26 | 2805 | int range_cyclic, cycled = 1, io_done = 0; |
55138e0b TT |
2806 | int needed_blocks, ret = 0; |
2807 | long desired_nr_to_write, nr_to_writebump = 0; | |
de89de6e | 2808 | loff_t range_start = wbc->range_start; |
5e745b04 | 2809 | struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb); |
61628a3f | 2810 | |
9bffad1e | 2811 | trace_ext4_da_writepages(inode, wbc); |
ba80b101 | 2812 | |
61628a3f MC |
2813 | /* |
2814 | * No pages to write? This is mainly a kludge to avoid starting | |
2815 | * a transaction for special inodes like journal inode on last iput() | |
2816 | * because that could violate lock ordering on umount | |
2817 | */ | |
a1d6cc56 | 2818 | if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) |
61628a3f | 2819 | return 0; |
2a21e37e TT |
2820 | |
2821 | /* | |
2822 | * If the filesystem has aborted, it is read-only, so return | |
2823 | * right away instead of dumping stack traces later on that | |
2824 | * will obscure the real source of the problem. We test | |
4ab2f15b | 2825 | * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because |
2a21e37e TT |
2826 | * the latter could be true if the filesystem is mounted |
2827 | * read-only, and in that case, ext4_da_writepages should | |
2828 | * *never* be called, so if that ever happens, we would want | |
2829 | * the stack trace. | |
2830 | */ | |
4ab2f15b | 2831 | if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED)) |
2a21e37e TT |
2832 | return -EROFS; |
2833 | ||
22208ded AK |
2834 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) |
2835 | range_whole = 1; | |
61628a3f | 2836 | |
2acf2c26 AK |
2837 | range_cyclic = wbc->range_cyclic; |
2838 | if (wbc->range_cyclic) { | |
22208ded | 2839 | index = mapping->writeback_index; |
2acf2c26 AK |
2840 | if (index) |
2841 | cycled = 0; | |
2842 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
2843 | wbc->range_end = LLONG_MAX; | |
2844 | wbc->range_cyclic = 0; | |
2845 | } else | |
22208ded | 2846 | index = wbc->range_start >> PAGE_CACHE_SHIFT; |
a1d6cc56 | 2847 | |
55138e0b TT |
2848 | /* |
2849 | * This works around two forms of stupidity. The first is in | |
2850 | * the writeback code, which caps the maximum number of pages | |
2851 | * written to be 1024 pages. This is wrong on multiple | |
2852 | * levels; different architectues have a different page size, | |
2853 | * which changes the maximum amount of data which gets | |
2854 | * written. Secondly, 4 megabytes is way too small. XFS | |
2855 | * forces this value to be 16 megabytes by multiplying | |
2856 | * nr_to_write parameter by four, and then relies on its | |
2857 | * allocator to allocate larger extents to make them | |
2858 | * contiguous. Unfortunately this brings us to the second | |
2859 | * stupidity, which is that ext4's mballoc code only allocates | |
2860 | * at most 2048 blocks. So we force contiguous writes up to | |
2861 | * the number of dirty blocks in the inode, or | |
2862 | * sbi->max_writeback_mb_bump whichever is smaller. | |
2863 | */ | |
2864 | max_pages = sbi->s_max_writeback_mb_bump << (20 - PAGE_CACHE_SHIFT); | |
2865 | if (!range_cyclic && range_whole) | |
2866 | desired_nr_to_write = wbc->nr_to_write * 8; | |
2867 | else | |
2868 | desired_nr_to_write = ext4_num_dirty_pages(inode, index, | |
2869 | max_pages); | |
2870 | if (desired_nr_to_write > max_pages) | |
2871 | desired_nr_to_write = max_pages; | |
2872 | ||
2873 | if (wbc->nr_to_write < desired_nr_to_write) { | |
2874 | nr_to_writebump = desired_nr_to_write - wbc->nr_to_write; | |
2875 | wbc->nr_to_write = desired_nr_to_write; | |
2876 | } | |
2877 | ||
df22291f AK |
2878 | mpd.wbc = wbc; |
2879 | mpd.inode = mapping->host; | |
2880 | ||
22208ded AK |
2881 | /* |
2882 | * we don't want write_cache_pages to update | |
2883 | * nr_to_write and writeback_index | |
2884 | */ | |
2885 | no_nrwrite_index_update = wbc->no_nrwrite_index_update; | |
2886 | wbc->no_nrwrite_index_update = 1; | |
2887 | pages_skipped = wbc->pages_skipped; | |
2888 | ||
2acf2c26 | 2889 | retry: |
22208ded | 2890 | while (!ret && wbc->nr_to_write > 0) { |
a1d6cc56 AK |
2891 | |
2892 | /* | |
2893 | * we insert one extent at a time. So we need | |
2894 | * credit needed for single extent allocation. | |
2895 | * journalled mode is currently not supported | |
2896 | * by delalloc | |
2897 | */ | |
2898 | BUG_ON(ext4_should_journal_data(inode)); | |
525f4ed8 | 2899 | needed_blocks = ext4_da_writepages_trans_blocks(inode); |
a1d6cc56 | 2900 | |
61628a3f MC |
2901 | /* start a new transaction*/ |
2902 | handle = ext4_journal_start(inode, needed_blocks); | |
2903 | if (IS_ERR(handle)) { | |
2904 | ret = PTR_ERR(handle); | |
1693918e | 2905 | ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: " |
a1d6cc56 AK |
2906 | "%ld pages, ino %lu; err %d\n", __func__, |
2907 | wbc->nr_to_write, inode->i_ino, ret); | |
61628a3f MC |
2908 | goto out_writepages; |
2909 | } | |
f63e6005 TT |
2910 | |
2911 | /* | |
2912 | * Now call __mpage_da_writepage to find the next | |
2913 | * contiguous region of logical blocks that need | |
2914 | * blocks to be allocated by ext4. We don't actually | |
2915 | * submit the blocks for I/O here, even though | |
2916 | * write_cache_pages thinks it will, and will set the | |
2917 | * pages as clean for write before calling | |
2918 | * __mpage_da_writepage(). | |
2919 | */ | |
2920 | mpd.b_size = 0; | |
2921 | mpd.b_state = 0; | |
2922 | mpd.b_blocknr = 0; | |
2923 | mpd.first_page = 0; | |
2924 | mpd.next_page = 0; | |
2925 | mpd.io_done = 0; | |
2926 | mpd.pages_written = 0; | |
2927 | mpd.retval = 0; | |
2928 | ret = write_cache_pages(mapping, wbc, __mpage_da_writepage, | |
2929 | &mpd); | |
2930 | /* | |
af901ca1 | 2931 | * If we have a contiguous extent of pages and we |
f63e6005 TT |
2932 | * haven't done the I/O yet, map the blocks and submit |
2933 | * them for I/O. | |
2934 | */ | |
2935 | if (!mpd.io_done && mpd.next_page != mpd.first_page) { | |
2936 | if (mpage_da_map_blocks(&mpd) == 0) | |
2937 | mpage_da_submit_io(&mpd); | |
2938 | mpd.io_done = 1; | |
2939 | ret = MPAGE_DA_EXTENT_TAIL; | |
2940 | } | |
b3a3ca8c | 2941 | trace_ext4_da_write_pages(inode, &mpd); |
f63e6005 | 2942 | wbc->nr_to_write -= mpd.pages_written; |
df22291f | 2943 | |
61628a3f | 2944 | ext4_journal_stop(handle); |
df22291f | 2945 | |
8f64b32e | 2946 | if ((mpd.retval == -ENOSPC) && sbi->s_journal) { |
22208ded AK |
2947 | /* commit the transaction which would |
2948 | * free blocks released in the transaction | |
2949 | * and try again | |
2950 | */ | |
df22291f | 2951 | jbd2_journal_force_commit_nested(sbi->s_journal); |
22208ded AK |
2952 | wbc->pages_skipped = pages_skipped; |
2953 | ret = 0; | |
2954 | } else if (ret == MPAGE_DA_EXTENT_TAIL) { | |
a1d6cc56 AK |
2955 | /* |
2956 | * got one extent now try with | |
2957 | * rest of the pages | |
2958 | */ | |
22208ded AK |
2959 | pages_written += mpd.pages_written; |
2960 | wbc->pages_skipped = pages_skipped; | |
a1d6cc56 | 2961 | ret = 0; |
2acf2c26 | 2962 | io_done = 1; |
22208ded | 2963 | } else if (wbc->nr_to_write) |
61628a3f MC |
2964 | /* |
2965 | * There is no more writeout needed | |
2966 | * or we requested for a noblocking writeout | |
2967 | * and we found the device congested | |
2968 | */ | |
61628a3f | 2969 | break; |
a1d6cc56 | 2970 | } |
2acf2c26 AK |
2971 | if (!io_done && !cycled) { |
2972 | cycled = 1; | |
2973 | index = 0; | |
2974 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
2975 | wbc->range_end = mapping->writeback_index - 1; | |
2976 | goto retry; | |
2977 | } | |
22208ded | 2978 | if (pages_skipped != wbc->pages_skipped) |
1693918e TT |
2979 | ext4_msg(inode->i_sb, KERN_CRIT, |
2980 | "This should not happen leaving %s " | |
2981 | "with nr_to_write = %ld ret = %d\n", | |
2982 | __func__, wbc->nr_to_write, ret); | |
22208ded AK |
2983 | |
2984 | /* Update index */ | |
2985 | index += pages_written; | |
2acf2c26 | 2986 | wbc->range_cyclic = range_cyclic; |
22208ded AK |
2987 | if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) |
2988 | /* | |
2989 | * set the writeback_index so that range_cyclic | |
2990 | * mode will write it back later | |
2991 | */ | |
2992 | mapping->writeback_index = index; | |
a1d6cc56 | 2993 | |
61628a3f | 2994 | out_writepages: |
22208ded AK |
2995 | if (!no_nrwrite_index_update) |
2996 | wbc->no_nrwrite_index_update = 0; | |
2faf2e19 | 2997 | wbc->nr_to_write -= nr_to_writebump; |
de89de6e | 2998 | wbc->range_start = range_start; |
9bffad1e | 2999 | trace_ext4_da_writepages_result(inode, wbc, ret, pages_written); |
61628a3f | 3000 | return ret; |
64769240 AT |
3001 | } |
3002 | ||
79f0be8d AK |
3003 | #define FALL_BACK_TO_NONDELALLOC 1 |
3004 | static int ext4_nonda_switch(struct super_block *sb) | |
3005 | { | |
3006 | s64 free_blocks, dirty_blocks; | |
3007 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
3008 | ||
3009 | /* | |
3010 | * switch to non delalloc mode if we are running low | |
3011 | * on free block. The free block accounting via percpu | |
179f7ebf | 3012 | * counters can get slightly wrong with percpu_counter_batch getting |
79f0be8d AK |
3013 | * accumulated on each CPU without updating global counters |
3014 | * Delalloc need an accurate free block accounting. So switch | |
3015 | * to non delalloc when we are near to error range. | |
3016 | */ | |
3017 | free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter); | |
3018 | dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyblocks_counter); | |
3019 | if (2 * free_blocks < 3 * dirty_blocks || | |
3020 | free_blocks < (dirty_blocks + EXT4_FREEBLOCKS_WATERMARK)) { | |
3021 | /* | |
c8afb446 ES |
3022 | * free block count is less than 150% of dirty blocks |
3023 | * or free blocks is less than watermark | |
79f0be8d AK |
3024 | */ |
3025 | return 1; | |
3026 | } | |
c8afb446 ES |
3027 | /* |
3028 | * Even if we don't switch but are nearing capacity, | |
3029 | * start pushing delalloc when 1/2 of free blocks are dirty. | |
3030 | */ | |
3031 | if (free_blocks < 2 * dirty_blocks) | |
3032 | writeback_inodes_sb_if_idle(sb); | |
3033 | ||
79f0be8d AK |
3034 | return 0; |
3035 | } | |
3036 | ||
64769240 | 3037 | static int ext4_da_write_begin(struct file *file, struct address_space *mapping, |
de9a55b8 TT |
3038 | loff_t pos, unsigned len, unsigned flags, |
3039 | struct page **pagep, void **fsdata) | |
64769240 | 3040 | { |
1db91382 | 3041 | int ret, retries = 0, quota_retries = 0; |
64769240 AT |
3042 | struct page *page; |
3043 | pgoff_t index; | |
3044 | unsigned from, to; | |
3045 | struct inode *inode = mapping->host; | |
3046 | handle_t *handle; | |
3047 | ||
3048 | index = pos >> PAGE_CACHE_SHIFT; | |
3049 | from = pos & (PAGE_CACHE_SIZE - 1); | |
3050 | to = from + len; | |
79f0be8d AK |
3051 | |
3052 | if (ext4_nonda_switch(inode->i_sb)) { | |
3053 | *fsdata = (void *)FALL_BACK_TO_NONDELALLOC; | |
3054 | return ext4_write_begin(file, mapping, pos, | |
3055 | len, flags, pagep, fsdata); | |
3056 | } | |
3057 | *fsdata = (void *)0; | |
9bffad1e | 3058 | trace_ext4_da_write_begin(inode, pos, len, flags); |
d2a17637 | 3059 | retry: |
64769240 AT |
3060 | /* |
3061 | * With delayed allocation, we don't log the i_disksize update | |
3062 | * if there is delayed block allocation. But we still need | |
3063 | * to journalling the i_disksize update if writes to the end | |
3064 | * of file which has an already mapped buffer. | |
3065 | */ | |
3066 | handle = ext4_journal_start(inode, 1); | |
3067 | if (IS_ERR(handle)) { | |
3068 | ret = PTR_ERR(handle); | |
3069 | goto out; | |
3070 | } | |
ebd3610b JK |
3071 | /* We cannot recurse into the filesystem as the transaction is already |
3072 | * started */ | |
3073 | flags |= AOP_FLAG_NOFS; | |
64769240 | 3074 | |
54566b2c | 3075 | page = grab_cache_page_write_begin(mapping, index, flags); |
d5a0d4f7 ES |
3076 | if (!page) { |
3077 | ext4_journal_stop(handle); | |
3078 | ret = -ENOMEM; | |
3079 | goto out; | |
3080 | } | |
64769240 AT |
3081 | *pagep = page; |
3082 | ||
3083 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, | |
b920c755 | 3084 | ext4_da_get_block_prep); |
64769240 AT |
3085 | if (ret < 0) { |
3086 | unlock_page(page); | |
3087 | ext4_journal_stop(handle); | |
3088 | page_cache_release(page); | |
ae4d5372 AK |
3089 | /* |
3090 | * block_write_begin may have instantiated a few blocks | |
3091 | * outside i_size. Trim these off again. Don't need | |
3092 | * i_size_read because we hold i_mutex. | |
3093 | */ | |
3094 | if (pos + len > inode->i_size) | |
b9a4207d | 3095 | ext4_truncate_failed_write(inode); |
64769240 AT |
3096 | } |
3097 | ||
d2a17637 MC |
3098 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
3099 | goto retry; | |
1db91382 AK |
3100 | |
3101 | if ((ret == -EDQUOT) && | |
3102 | EXT4_I(inode)->i_reserved_meta_blocks && | |
3103 | (quota_retries++ < 3)) { | |
3104 | /* | |
3105 | * Since we often over-estimate the number of meta | |
3106 | * data blocks required, we may sometimes get a | |
3107 | * spurios out of quota error even though there would | |
3108 | * be enough space once we write the data blocks and | |
3109 | * find out how many meta data blocks were _really_ | |
3110 | * required. So try forcing the inode write to see if | |
3111 | * that helps. | |
3112 | */ | |
3113 | write_inode_now(inode, (quota_retries == 3)); | |
3114 | goto retry; | |
3115 | } | |
64769240 AT |
3116 | out: |
3117 | return ret; | |
3118 | } | |
3119 | ||
632eaeab MC |
3120 | /* |
3121 | * Check if we should update i_disksize | |
3122 | * when write to the end of file but not require block allocation | |
3123 | */ | |
3124 | static int ext4_da_should_update_i_disksize(struct page *page, | |
de9a55b8 | 3125 | unsigned long offset) |
632eaeab MC |
3126 | { |
3127 | struct buffer_head *bh; | |
3128 | struct inode *inode = page->mapping->host; | |
3129 | unsigned int idx; | |
3130 | int i; | |
3131 | ||
3132 | bh = page_buffers(page); | |
3133 | idx = offset >> inode->i_blkbits; | |
3134 | ||
af5bc92d | 3135 | for (i = 0; i < idx; i++) |
632eaeab MC |
3136 | bh = bh->b_this_page; |
3137 | ||
29fa89d0 | 3138 | if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh)) |
632eaeab MC |
3139 | return 0; |
3140 | return 1; | |
3141 | } | |
3142 | ||
64769240 | 3143 | static int ext4_da_write_end(struct file *file, |
de9a55b8 TT |
3144 | struct address_space *mapping, |
3145 | loff_t pos, unsigned len, unsigned copied, | |
3146 | struct page *page, void *fsdata) | |
64769240 AT |
3147 | { |
3148 | struct inode *inode = mapping->host; | |
3149 | int ret = 0, ret2; | |
3150 | handle_t *handle = ext4_journal_current_handle(); | |
3151 | loff_t new_i_size; | |
632eaeab | 3152 | unsigned long start, end; |
79f0be8d AK |
3153 | int write_mode = (int)(unsigned long)fsdata; |
3154 | ||
3155 | if (write_mode == FALL_BACK_TO_NONDELALLOC) { | |
3156 | if (ext4_should_order_data(inode)) { | |
3157 | return ext4_ordered_write_end(file, mapping, pos, | |
3158 | len, copied, page, fsdata); | |
3159 | } else if (ext4_should_writeback_data(inode)) { | |
3160 | return ext4_writeback_write_end(file, mapping, pos, | |
3161 | len, copied, page, fsdata); | |
3162 | } else { | |
3163 | BUG(); | |
3164 | } | |
3165 | } | |
632eaeab | 3166 | |
9bffad1e | 3167 | trace_ext4_da_write_end(inode, pos, len, copied); |
632eaeab | 3168 | start = pos & (PAGE_CACHE_SIZE - 1); |
af5bc92d | 3169 | end = start + copied - 1; |
64769240 AT |
3170 | |
3171 | /* | |
3172 | * generic_write_end() will run mark_inode_dirty() if i_size | |
3173 | * changes. So let's piggyback the i_disksize mark_inode_dirty | |
3174 | * into that. | |
3175 | */ | |
3176 | ||
3177 | new_i_size = pos + copied; | |
632eaeab MC |
3178 | if (new_i_size > EXT4_I(inode)->i_disksize) { |
3179 | if (ext4_da_should_update_i_disksize(page, end)) { | |
3180 | down_write(&EXT4_I(inode)->i_data_sem); | |
3181 | if (new_i_size > EXT4_I(inode)->i_disksize) { | |
3182 | /* | |
3183 | * Updating i_disksize when extending file | |
3184 | * without needing block allocation | |
3185 | */ | |
3186 | if (ext4_should_order_data(inode)) | |
3187 | ret = ext4_jbd2_file_inode(handle, | |
3188 | inode); | |
64769240 | 3189 | |
632eaeab MC |
3190 | EXT4_I(inode)->i_disksize = new_i_size; |
3191 | } | |
3192 | up_write(&EXT4_I(inode)->i_data_sem); | |
cf17fea6 AK |
3193 | /* We need to mark inode dirty even if |
3194 | * new_i_size is less that inode->i_size | |
3195 | * bu greater than i_disksize.(hint delalloc) | |
3196 | */ | |
3197 | ext4_mark_inode_dirty(handle, inode); | |
64769240 | 3198 | } |
632eaeab | 3199 | } |
64769240 AT |
3200 | ret2 = generic_write_end(file, mapping, pos, len, copied, |
3201 | page, fsdata); | |
3202 | copied = ret2; | |
3203 | if (ret2 < 0) | |
3204 | ret = ret2; | |
3205 | ret2 = ext4_journal_stop(handle); | |
3206 | if (!ret) | |
3207 | ret = ret2; | |
3208 | ||
3209 | return ret ? ret : copied; | |
3210 | } | |
3211 | ||
3212 | static void ext4_da_invalidatepage(struct page *page, unsigned long offset) | |
3213 | { | |
64769240 AT |
3214 | /* |
3215 | * Drop reserved blocks | |
3216 | */ | |
3217 | BUG_ON(!PageLocked(page)); | |
3218 | if (!page_has_buffers(page)) | |
3219 | goto out; | |
3220 | ||
d2a17637 | 3221 | ext4_da_page_release_reservation(page, offset); |
64769240 AT |
3222 | |
3223 | out: | |
3224 | ext4_invalidatepage(page, offset); | |
3225 | ||
3226 | return; | |
3227 | } | |
3228 | ||
ccd2506b TT |
3229 | /* |
3230 | * Force all delayed allocation blocks to be allocated for a given inode. | |
3231 | */ | |
3232 | int ext4_alloc_da_blocks(struct inode *inode) | |
3233 | { | |
fb40ba0d TT |
3234 | trace_ext4_alloc_da_blocks(inode); |
3235 | ||
ccd2506b TT |
3236 | if (!EXT4_I(inode)->i_reserved_data_blocks && |
3237 | !EXT4_I(inode)->i_reserved_meta_blocks) | |
3238 | return 0; | |
3239 | ||
3240 | /* | |
3241 | * We do something simple for now. The filemap_flush() will | |
3242 | * also start triggering a write of the data blocks, which is | |
3243 | * not strictly speaking necessary (and for users of | |
3244 | * laptop_mode, not even desirable). However, to do otherwise | |
3245 | * would require replicating code paths in: | |
de9a55b8 | 3246 | * |
ccd2506b TT |
3247 | * ext4_da_writepages() -> |
3248 | * write_cache_pages() ---> (via passed in callback function) | |
3249 | * __mpage_da_writepage() --> | |
3250 | * mpage_add_bh_to_extent() | |
3251 | * mpage_da_map_blocks() | |
3252 | * | |
3253 | * The problem is that write_cache_pages(), located in | |
3254 | * mm/page-writeback.c, marks pages clean in preparation for | |
3255 | * doing I/O, which is not desirable if we're not planning on | |
3256 | * doing I/O at all. | |
3257 | * | |
3258 | * We could call write_cache_pages(), and then redirty all of | |
3259 | * the pages by calling redirty_page_for_writeback() but that | |
3260 | * would be ugly in the extreme. So instead we would need to | |
3261 | * replicate parts of the code in the above functions, | |
3262 | * simplifying them becuase we wouldn't actually intend to | |
3263 | * write out the pages, but rather only collect contiguous | |
3264 | * logical block extents, call the multi-block allocator, and | |
3265 | * then update the buffer heads with the block allocations. | |
de9a55b8 | 3266 | * |
ccd2506b TT |
3267 | * For now, though, we'll cheat by calling filemap_flush(), |
3268 | * which will map the blocks, and start the I/O, but not | |
3269 | * actually wait for the I/O to complete. | |
3270 | */ | |
3271 | return filemap_flush(inode->i_mapping); | |
3272 | } | |
64769240 | 3273 | |
ac27a0ec DK |
3274 | /* |
3275 | * bmap() is special. It gets used by applications such as lilo and by | |
3276 | * the swapper to find the on-disk block of a specific piece of data. | |
3277 | * | |
3278 | * Naturally, this is dangerous if the block concerned is still in the | |
617ba13b | 3279 | * journal. If somebody makes a swapfile on an ext4 data-journaling |
ac27a0ec DK |
3280 | * filesystem and enables swap, then they may get a nasty shock when the |
3281 | * data getting swapped to that swapfile suddenly gets overwritten by | |
3282 | * the original zero's written out previously to the journal and | |
3283 | * awaiting writeback in the kernel's buffer cache. | |
3284 | * | |
3285 | * So, if we see any bmap calls here on a modified, data-journaled file, | |
3286 | * take extra steps to flush any blocks which might be in the cache. | |
3287 | */ | |
617ba13b | 3288 | static sector_t ext4_bmap(struct address_space *mapping, sector_t block) |
ac27a0ec DK |
3289 | { |
3290 | struct inode *inode = mapping->host; | |
3291 | journal_t *journal; | |
3292 | int err; | |
3293 | ||
64769240 AT |
3294 | if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && |
3295 | test_opt(inode->i_sb, DELALLOC)) { | |
3296 | /* | |
3297 | * With delalloc we want to sync the file | |
3298 | * so that we can make sure we allocate | |
3299 | * blocks for file | |
3300 | */ | |
3301 | filemap_write_and_wait(mapping); | |
3302 | } | |
3303 | ||
0390131b | 3304 | if (EXT4_JOURNAL(inode) && EXT4_I(inode)->i_state & EXT4_STATE_JDATA) { |
ac27a0ec DK |
3305 | /* |
3306 | * This is a REALLY heavyweight approach, but the use of | |
3307 | * bmap on dirty files is expected to be extremely rare: | |
3308 | * only if we run lilo or swapon on a freshly made file | |
3309 | * do we expect this to happen. | |
3310 | * | |
3311 | * (bmap requires CAP_SYS_RAWIO so this does not | |
3312 | * represent an unprivileged user DOS attack --- we'd be | |
3313 | * in trouble if mortal users could trigger this path at | |
3314 | * will.) | |
3315 | * | |
617ba13b | 3316 | * NB. EXT4_STATE_JDATA is not set on files other than |
ac27a0ec DK |
3317 | * regular files. If somebody wants to bmap a directory |
3318 | * or symlink and gets confused because the buffer | |
3319 | * hasn't yet been flushed to disk, they deserve | |
3320 | * everything they get. | |
3321 | */ | |
3322 | ||
617ba13b MC |
3323 | EXT4_I(inode)->i_state &= ~EXT4_STATE_JDATA; |
3324 | journal = EXT4_JOURNAL(inode); | |
dab291af MC |
3325 | jbd2_journal_lock_updates(journal); |
3326 | err = jbd2_journal_flush(journal); | |
3327 | jbd2_journal_unlock_updates(journal); | |
ac27a0ec DK |
3328 | |
3329 | if (err) | |
3330 | return 0; | |
3331 | } | |
3332 | ||
af5bc92d | 3333 | return generic_block_bmap(mapping, block, ext4_get_block); |
ac27a0ec DK |
3334 | } |
3335 | ||
617ba13b | 3336 | static int ext4_readpage(struct file *file, struct page *page) |
ac27a0ec | 3337 | { |
617ba13b | 3338 | return mpage_readpage(page, ext4_get_block); |
ac27a0ec DK |
3339 | } |
3340 | ||
3341 | static int | |
617ba13b | 3342 | ext4_readpages(struct file *file, struct address_space *mapping, |
ac27a0ec DK |
3343 | struct list_head *pages, unsigned nr_pages) |
3344 | { | |
617ba13b | 3345 | return mpage_readpages(mapping, pages, nr_pages, ext4_get_block); |
ac27a0ec DK |
3346 | } |
3347 | ||
617ba13b | 3348 | static void ext4_invalidatepage(struct page *page, unsigned long offset) |
ac27a0ec | 3349 | { |
617ba13b | 3350 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
ac27a0ec DK |
3351 | |
3352 | /* | |
3353 | * If it's a full truncate we just forget about the pending dirtying | |
3354 | */ | |
3355 | if (offset == 0) | |
3356 | ClearPageChecked(page); | |
3357 | ||
0390131b FM |
3358 | if (journal) |
3359 | jbd2_journal_invalidatepage(journal, page, offset); | |
3360 | else | |
3361 | block_invalidatepage(page, offset); | |
ac27a0ec DK |
3362 | } |
3363 | ||
617ba13b | 3364 | static int ext4_releasepage(struct page *page, gfp_t wait) |
ac27a0ec | 3365 | { |
617ba13b | 3366 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
ac27a0ec DK |
3367 | |
3368 | WARN_ON(PageChecked(page)); | |
3369 | if (!page_has_buffers(page)) | |
3370 | return 0; | |
0390131b FM |
3371 | if (journal) |
3372 | return jbd2_journal_try_to_free_buffers(journal, page, wait); | |
3373 | else | |
3374 | return try_to_free_buffers(page); | |
ac27a0ec DK |
3375 | } |
3376 | ||
3377 | /* | |
4c0425ff MC |
3378 | * O_DIRECT for ext3 (or indirect map) based files |
3379 | * | |
ac27a0ec DK |
3380 | * If the O_DIRECT write will extend the file then add this inode to the |
3381 | * orphan list. So recovery will truncate it back to the original size | |
3382 | * if the machine crashes during the write. | |
3383 | * | |
3384 | * If the O_DIRECT write is intantiating holes inside i_size and the machine | |
7fb5409d JK |
3385 | * crashes then stale disk data _may_ be exposed inside the file. But current |
3386 | * VFS code falls back into buffered path in that case so we are safe. | |
ac27a0ec | 3387 | */ |
4c0425ff | 3388 | static ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb, |
de9a55b8 TT |
3389 | const struct iovec *iov, loff_t offset, |
3390 | unsigned long nr_segs) | |
ac27a0ec DK |
3391 | { |
3392 | struct file *file = iocb->ki_filp; | |
3393 | struct inode *inode = file->f_mapping->host; | |
617ba13b | 3394 | struct ext4_inode_info *ei = EXT4_I(inode); |
7fb5409d | 3395 | handle_t *handle; |
ac27a0ec DK |
3396 | ssize_t ret; |
3397 | int orphan = 0; | |
3398 | size_t count = iov_length(iov, nr_segs); | |
fbbf6945 | 3399 | int retries = 0; |
ac27a0ec DK |
3400 | |
3401 | if (rw == WRITE) { | |
3402 | loff_t final_size = offset + count; | |
3403 | ||
ac27a0ec | 3404 | if (final_size > inode->i_size) { |
7fb5409d JK |
3405 | /* Credits for sb + inode write */ |
3406 | handle = ext4_journal_start(inode, 2); | |
3407 | if (IS_ERR(handle)) { | |
3408 | ret = PTR_ERR(handle); | |
3409 | goto out; | |
3410 | } | |
617ba13b | 3411 | ret = ext4_orphan_add(handle, inode); |
7fb5409d JK |
3412 | if (ret) { |
3413 | ext4_journal_stop(handle); | |
3414 | goto out; | |
3415 | } | |
ac27a0ec DK |
3416 | orphan = 1; |
3417 | ei->i_disksize = inode->i_size; | |
7fb5409d | 3418 | ext4_journal_stop(handle); |
ac27a0ec DK |
3419 | } |
3420 | } | |
3421 | ||
fbbf6945 | 3422 | retry: |
ac27a0ec DK |
3423 | ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, |
3424 | offset, nr_segs, | |
617ba13b | 3425 | ext4_get_block, NULL); |
fbbf6945 ES |
3426 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
3427 | goto retry; | |
ac27a0ec | 3428 | |
7fb5409d | 3429 | if (orphan) { |
ac27a0ec DK |
3430 | int err; |
3431 | ||
7fb5409d JK |
3432 | /* Credits for sb + inode write */ |
3433 | handle = ext4_journal_start(inode, 2); | |
3434 | if (IS_ERR(handle)) { | |
3435 | /* This is really bad luck. We've written the data | |
3436 | * but cannot extend i_size. Bail out and pretend | |
3437 | * the write failed... */ | |
3438 | ret = PTR_ERR(handle); | |
3439 | goto out; | |
3440 | } | |
3441 | if (inode->i_nlink) | |
617ba13b | 3442 | ext4_orphan_del(handle, inode); |
7fb5409d | 3443 | if (ret > 0) { |
ac27a0ec DK |
3444 | loff_t end = offset + ret; |
3445 | if (end > inode->i_size) { | |
3446 | ei->i_disksize = end; | |
3447 | i_size_write(inode, end); | |
3448 | /* | |
3449 | * We're going to return a positive `ret' | |
3450 | * here due to non-zero-length I/O, so there's | |
3451 | * no way of reporting error returns from | |
617ba13b | 3452 | * ext4_mark_inode_dirty() to userspace. So |
ac27a0ec DK |
3453 | * ignore it. |
3454 | */ | |
617ba13b | 3455 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
3456 | } |
3457 | } | |
617ba13b | 3458 | err = ext4_journal_stop(handle); |
ac27a0ec DK |
3459 | if (ret == 0) |
3460 | ret = err; | |
3461 | } | |
3462 | out: | |
3463 | return ret; | |
3464 | } | |
3465 | ||
4c0425ff MC |
3466 | static int ext4_get_block_dio_write(struct inode *inode, sector_t iblock, |
3467 | struct buffer_head *bh_result, int create) | |
3468 | { | |
3469 | handle_t *handle = NULL; | |
3470 | int ret = 0; | |
3471 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; | |
3472 | int dio_credits; | |
3473 | ||
8d5d02e6 MC |
3474 | ext4_debug("ext4_get_block_dio_write: inode %lu, create flag %d\n", |
3475 | inode->i_ino, create); | |
4c0425ff MC |
3476 | /* |
3477 | * DIO VFS code passes create = 0 flag for write to | |
3478 | * the middle of file. It does this to avoid block | |
3479 | * allocation for holes, to prevent expose stale data | |
3480 | * out when there is parallel buffered read (which does | |
3481 | * not hold the i_mutex lock) while direct IO write has | |
3482 | * not completed. DIO request on holes finally falls back | |
3483 | * to buffered IO for this reason. | |
3484 | * | |
3485 | * For ext4 extent based file, since we support fallocate, | |
3486 | * new allocated extent as uninitialized, for holes, we | |
3487 | * could fallocate blocks for holes, thus parallel | |
3488 | * buffered IO read will zero out the page when read on | |
3489 | * a hole while parallel DIO write to the hole has not completed. | |
3490 | * | |
3491 | * when we come here, we know it's a direct IO write to | |
3492 | * to the middle of file (<i_size) | |
3493 | * so it's safe to override the create flag from VFS. | |
3494 | */ | |
3495 | create = EXT4_GET_BLOCKS_DIO_CREATE_EXT; | |
3496 | ||
3497 | if (max_blocks > DIO_MAX_BLOCKS) | |
3498 | max_blocks = DIO_MAX_BLOCKS; | |
3499 | dio_credits = ext4_chunk_trans_blocks(inode, max_blocks); | |
3500 | handle = ext4_journal_start(inode, dio_credits); | |
3501 | if (IS_ERR(handle)) { | |
3502 | ret = PTR_ERR(handle); | |
3503 | goto out; | |
3504 | } | |
3505 | ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result, | |
3506 | create); | |
3507 | if (ret > 0) { | |
3508 | bh_result->b_size = (ret << inode->i_blkbits); | |
3509 | ret = 0; | |
3510 | } | |
3511 | ext4_journal_stop(handle); | |
3512 | out: | |
3513 | return ret; | |
3514 | } | |
3515 | ||
4c0425ff MC |
3516 | static void ext4_free_io_end(ext4_io_end_t *io) |
3517 | { | |
8d5d02e6 MC |
3518 | BUG_ON(!io); |
3519 | iput(io->inode); | |
4c0425ff MC |
3520 | kfree(io); |
3521 | } | |
8d5d02e6 MC |
3522 | static void dump_aio_dio_list(struct inode * inode) |
3523 | { | |
3524 | #ifdef EXT4_DEBUG | |
3525 | struct list_head *cur, *before, *after; | |
3526 | ext4_io_end_t *io, *io0, *io1; | |
3527 | ||
3528 | if (list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)){ | |
3529 | ext4_debug("inode %lu aio dio list is empty\n", inode->i_ino); | |
3530 | return; | |
3531 | } | |
3532 | ||
3533 | ext4_debug("Dump inode %lu aio_dio_completed_IO list \n", inode->i_ino); | |
3534 | list_for_each_entry(io, &EXT4_I(inode)->i_aio_dio_complete_list, list){ | |
3535 | cur = &io->list; | |
3536 | before = cur->prev; | |
3537 | io0 = container_of(before, ext4_io_end_t, list); | |
3538 | after = cur->next; | |
3539 | io1 = container_of(after, ext4_io_end_t, list); | |
3540 | ||
3541 | ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n", | |
3542 | io, inode->i_ino, io0, io1); | |
3543 | } | |
3544 | #endif | |
3545 | } | |
4c0425ff MC |
3546 | |
3547 | /* | |
4c0425ff MC |
3548 | * check a range of space and convert unwritten extents to written. |
3549 | */ | |
8d5d02e6 | 3550 | static int ext4_end_aio_dio_nolock(ext4_io_end_t *io) |
4c0425ff | 3551 | { |
4c0425ff MC |
3552 | struct inode *inode = io->inode; |
3553 | loff_t offset = io->offset; | |
3554 | size_t size = io->size; | |
3555 | int ret = 0; | |
4c0425ff | 3556 | |
8d5d02e6 MC |
3557 | ext4_debug("end_aio_dio_onlock: io 0x%p from inode %lu,list->next 0x%p," |
3558 | "list->prev 0x%p\n", | |
3559 | io, inode->i_ino, io->list.next, io->list.prev); | |
3560 | ||
3561 | if (list_empty(&io->list)) | |
3562 | return ret; | |
3563 | ||
3564 | if (io->flag != DIO_AIO_UNWRITTEN) | |
3565 | return ret; | |
3566 | ||
4c0425ff MC |
3567 | if (offset + size <= i_size_read(inode)) |
3568 | ret = ext4_convert_unwritten_extents(inode, offset, size); | |
3569 | ||
8d5d02e6 | 3570 | if (ret < 0) { |
4c0425ff | 3571 | printk(KERN_EMERG "%s: failed to convert unwritten" |
8d5d02e6 MC |
3572 | "extents to written extents, error is %d" |
3573 | " io is still on inode %lu aio dio list\n", | |
3574 | __func__, ret, inode->i_ino); | |
3575 | return ret; | |
3576 | } | |
4c0425ff | 3577 | |
8d5d02e6 MC |
3578 | /* clear the DIO AIO unwritten flag */ |
3579 | io->flag = 0; | |
3580 | return ret; | |
4c0425ff | 3581 | } |
8d5d02e6 MC |
3582 | /* |
3583 | * work on completed aio dio IO, to convert unwritten extents to extents | |
3584 | */ | |
3585 | static void ext4_end_aio_dio_work(struct work_struct *work) | |
3586 | { | |
3587 | ext4_io_end_t *io = container_of(work, ext4_io_end_t, work); | |
3588 | struct inode *inode = io->inode; | |
3589 | int ret = 0; | |
4c0425ff | 3590 | |
8d5d02e6 MC |
3591 | mutex_lock(&inode->i_mutex); |
3592 | ret = ext4_end_aio_dio_nolock(io); | |
3593 | if (ret >= 0) { | |
3594 | if (!list_empty(&io->list)) | |
3595 | list_del_init(&io->list); | |
3596 | ext4_free_io_end(io); | |
3597 | } | |
3598 | mutex_unlock(&inode->i_mutex); | |
3599 | } | |
3600 | /* | |
3601 | * This function is called from ext4_sync_file(). | |
3602 | * | |
3603 | * When AIO DIO IO is completed, the work to convert unwritten | |
3604 | * extents to written is queued on workqueue but may not get immediately | |
3605 | * scheduled. When fsync is called, we need to ensure the | |
3606 | * conversion is complete before fsync returns. | |
3607 | * The inode keeps track of a list of completed AIO from DIO path | |
3608 | * that might needs to do the conversion. This function walks through | |
3609 | * the list and convert the related unwritten extents to written. | |
3610 | */ | |
3611 | int flush_aio_dio_completed_IO(struct inode *inode) | |
3612 | { | |
3613 | ext4_io_end_t *io; | |
3614 | int ret = 0; | |
3615 | int ret2 = 0; | |
3616 | ||
3617 | if (list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)) | |
3618 | return ret; | |
3619 | ||
3620 | dump_aio_dio_list(inode); | |
3621 | while (!list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)){ | |
3622 | io = list_entry(EXT4_I(inode)->i_aio_dio_complete_list.next, | |
3623 | ext4_io_end_t, list); | |
3624 | /* | |
3625 | * Calling ext4_end_aio_dio_nolock() to convert completed | |
3626 | * IO to written. | |
3627 | * | |
3628 | * When ext4_sync_file() is called, run_queue() may already | |
3629 | * about to flush the work corresponding to this io structure. | |
3630 | * It will be upset if it founds the io structure related | |
3631 | * to the work-to-be schedule is freed. | |
3632 | * | |
3633 | * Thus we need to keep the io structure still valid here after | |
3634 | * convertion finished. The io structure has a flag to | |
3635 | * avoid double converting from both fsync and background work | |
3636 | * queue work. | |
3637 | */ | |
3638 | ret = ext4_end_aio_dio_nolock(io); | |
3639 | if (ret < 0) | |
3640 | ret2 = ret; | |
3641 | else | |
3642 | list_del_init(&io->list); | |
3643 | } | |
3644 | return (ret2 < 0) ? ret2 : 0; | |
3645 | } | |
3646 | ||
3647 | static ext4_io_end_t *ext4_init_io_end (struct inode *inode) | |
4c0425ff MC |
3648 | { |
3649 | ext4_io_end_t *io = NULL; | |
3650 | ||
3651 | io = kmalloc(sizeof(*io), GFP_NOFS); | |
3652 | ||
3653 | if (io) { | |
8d5d02e6 | 3654 | igrab(inode); |
4c0425ff | 3655 | io->inode = inode; |
8d5d02e6 | 3656 | io->flag = 0; |
4c0425ff MC |
3657 | io->offset = 0; |
3658 | io->size = 0; | |
3659 | io->error = 0; | |
8d5d02e6 MC |
3660 | INIT_WORK(&io->work, ext4_end_aio_dio_work); |
3661 | INIT_LIST_HEAD(&io->list); | |
4c0425ff MC |
3662 | } |
3663 | ||
3664 | return io; | |
3665 | } | |
3666 | ||
3667 | static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset, | |
3668 | ssize_t size, void *private) | |
3669 | { | |
3670 | ext4_io_end_t *io_end = iocb->private; | |
3671 | struct workqueue_struct *wq; | |
3672 | ||
4b70df18 M |
3673 | /* if not async direct IO or dio with 0 bytes write, just return */ |
3674 | if (!io_end || !size) | |
3675 | return; | |
3676 | ||
8d5d02e6 MC |
3677 | ext_debug("ext4_end_io_dio(): io_end 0x%p" |
3678 | "for inode %lu, iocb 0x%p, offset %llu, size %llu\n", | |
3679 | iocb->private, io_end->inode->i_ino, iocb, offset, | |
3680 | size); | |
8d5d02e6 MC |
3681 | |
3682 | /* if not aio dio with unwritten extents, just free io and return */ | |
3683 | if (io_end->flag != DIO_AIO_UNWRITTEN){ | |
3684 | ext4_free_io_end(io_end); | |
3685 | iocb->private = NULL; | |
4c0425ff | 3686 | return; |
8d5d02e6 MC |
3687 | } |
3688 | ||
4c0425ff MC |
3689 | io_end->offset = offset; |
3690 | io_end->size = size; | |
3691 | wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq; | |
3692 | ||
8d5d02e6 | 3693 | /* queue the work to convert unwritten extents to written */ |
4c0425ff MC |
3694 | queue_work(wq, &io_end->work); |
3695 | ||
8d5d02e6 MC |
3696 | /* Add the io_end to per-inode completed aio dio list*/ |
3697 | list_add_tail(&io_end->list, | |
3698 | &EXT4_I(io_end->inode)->i_aio_dio_complete_list); | |
4c0425ff MC |
3699 | iocb->private = NULL; |
3700 | } | |
3701 | /* | |
3702 | * For ext4 extent files, ext4 will do direct-io write to holes, | |
3703 | * preallocated extents, and those write extend the file, no need to | |
3704 | * fall back to buffered IO. | |
3705 | * | |
3706 | * For holes, we fallocate those blocks, mark them as unintialized | |
3707 | * If those blocks were preallocated, we mark sure they are splited, but | |
3708 | * still keep the range to write as unintialized. | |
3709 | * | |
8d5d02e6 MC |
3710 | * The unwrritten extents will be converted to written when DIO is completed. |
3711 | * For async direct IO, since the IO may still pending when return, we | |
3712 | * set up an end_io call back function, which will do the convertion | |
3713 | * when async direct IO completed. | |
4c0425ff MC |
3714 | * |
3715 | * If the O_DIRECT write will extend the file then add this inode to the | |
3716 | * orphan list. So recovery will truncate it back to the original size | |
3717 | * if the machine crashes during the write. | |
3718 | * | |
3719 | */ | |
3720 | static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, | |
3721 | const struct iovec *iov, loff_t offset, | |
3722 | unsigned long nr_segs) | |
3723 | { | |
3724 | struct file *file = iocb->ki_filp; | |
3725 | struct inode *inode = file->f_mapping->host; | |
3726 | ssize_t ret; | |
3727 | size_t count = iov_length(iov, nr_segs); | |
3728 | ||
3729 | loff_t final_size = offset + count; | |
3730 | if (rw == WRITE && final_size <= inode->i_size) { | |
3731 | /* | |
8d5d02e6 MC |
3732 | * We could direct write to holes and fallocate. |
3733 | * | |
3734 | * Allocated blocks to fill the hole are marked as uninitialized | |
4c0425ff MC |
3735 | * to prevent paralel buffered read to expose the stale data |
3736 | * before DIO complete the data IO. | |
8d5d02e6 MC |
3737 | * |
3738 | * As to previously fallocated extents, ext4 get_block | |
4c0425ff MC |
3739 | * will just simply mark the buffer mapped but still |
3740 | * keep the extents uninitialized. | |
3741 | * | |
8d5d02e6 MC |
3742 | * for non AIO case, we will convert those unwritten extents |
3743 | * to written after return back from blockdev_direct_IO. | |
3744 | * | |
3745 | * for async DIO, the conversion needs to be defered when | |
3746 | * the IO is completed. The ext4 end_io callback function | |
3747 | * will be called to take care of the conversion work. | |
3748 | * Here for async case, we allocate an io_end structure to | |
3749 | * hook to the iocb. | |
4c0425ff | 3750 | */ |
8d5d02e6 MC |
3751 | iocb->private = NULL; |
3752 | EXT4_I(inode)->cur_aio_dio = NULL; | |
3753 | if (!is_sync_kiocb(iocb)) { | |
3754 | iocb->private = ext4_init_io_end(inode); | |
3755 | if (!iocb->private) | |
3756 | return -ENOMEM; | |
3757 | /* | |
3758 | * we save the io structure for current async | |
3759 | * direct IO, so that later ext4_get_blocks() | |
3760 | * could flag the io structure whether there | |
3761 | * is a unwritten extents needs to be converted | |
3762 | * when IO is completed. | |
3763 | */ | |
3764 | EXT4_I(inode)->cur_aio_dio = iocb->private; | |
3765 | } | |
3766 | ||
4c0425ff MC |
3767 | ret = blockdev_direct_IO(rw, iocb, inode, |
3768 | inode->i_sb->s_bdev, iov, | |
3769 | offset, nr_segs, | |
3770 | ext4_get_block_dio_write, | |
3771 | ext4_end_io_dio); | |
8d5d02e6 MC |
3772 | if (iocb->private) |
3773 | EXT4_I(inode)->cur_aio_dio = NULL; | |
3774 | /* | |
3775 | * The io_end structure takes a reference to the inode, | |
3776 | * that structure needs to be destroyed and the | |
3777 | * reference to the inode need to be dropped, when IO is | |
3778 | * complete, even with 0 byte write, or failed. | |
3779 | * | |
3780 | * In the successful AIO DIO case, the io_end structure will be | |
3781 | * desctroyed and the reference to the inode will be dropped | |
3782 | * after the end_io call back function is called. | |
3783 | * | |
3784 | * In the case there is 0 byte write, or error case, since | |
3785 | * VFS direct IO won't invoke the end_io call back function, | |
3786 | * we need to free the end_io structure here. | |
3787 | */ | |
3788 | if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) { | |
3789 | ext4_free_io_end(iocb->private); | |
3790 | iocb->private = NULL; | |
5f524950 M |
3791 | } else if (ret > 0 && (EXT4_I(inode)->i_state & |
3792 | EXT4_STATE_DIO_UNWRITTEN)) { | |
109f5565 | 3793 | int err; |
8d5d02e6 MC |
3794 | /* |
3795 | * for non AIO case, since the IO is already | |
3796 | * completed, we could do the convertion right here | |
3797 | */ | |
109f5565 M |
3798 | err = ext4_convert_unwritten_extents(inode, |
3799 | offset, ret); | |
3800 | if (err < 0) | |
3801 | ret = err; | |
5f524950 | 3802 | EXT4_I(inode)->i_state &= ~EXT4_STATE_DIO_UNWRITTEN; |
109f5565 | 3803 | } |
4c0425ff MC |
3804 | return ret; |
3805 | } | |
8d5d02e6 MC |
3806 | |
3807 | /* for write the the end of file case, we fall back to old way */ | |
4c0425ff MC |
3808 | return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs); |
3809 | } | |
3810 | ||
3811 | static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb, | |
3812 | const struct iovec *iov, loff_t offset, | |
3813 | unsigned long nr_segs) | |
3814 | { | |
3815 | struct file *file = iocb->ki_filp; | |
3816 | struct inode *inode = file->f_mapping->host; | |
3817 | ||
3818 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) | |
3819 | return ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs); | |
3820 | ||
3821 | return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs); | |
3822 | } | |
3823 | ||
ac27a0ec | 3824 | /* |
617ba13b | 3825 | * Pages can be marked dirty completely asynchronously from ext4's journalling |
ac27a0ec DK |
3826 | * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do |
3827 | * much here because ->set_page_dirty is called under VFS locks. The page is | |
3828 | * not necessarily locked. | |
3829 | * | |
3830 | * We cannot just dirty the page and leave attached buffers clean, because the | |
3831 | * buffers' dirty state is "definitive". We cannot just set the buffers dirty | |
3832 | * or jbddirty because all the journalling code will explode. | |
3833 | * | |
3834 | * So what we do is to mark the page "pending dirty" and next time writepage | |
3835 | * is called, propagate that into the buffers appropriately. | |
3836 | */ | |
617ba13b | 3837 | static int ext4_journalled_set_page_dirty(struct page *page) |
ac27a0ec DK |
3838 | { |
3839 | SetPageChecked(page); | |
3840 | return __set_page_dirty_nobuffers(page); | |
3841 | } | |
3842 | ||
617ba13b | 3843 | static const struct address_space_operations ext4_ordered_aops = { |
8ab22b9a HH |
3844 | .readpage = ext4_readpage, |
3845 | .readpages = ext4_readpages, | |
43ce1d23 | 3846 | .writepage = ext4_writepage, |
8ab22b9a HH |
3847 | .sync_page = block_sync_page, |
3848 | .write_begin = ext4_write_begin, | |
3849 | .write_end = ext4_ordered_write_end, | |
3850 | .bmap = ext4_bmap, | |
3851 | .invalidatepage = ext4_invalidatepage, | |
3852 | .releasepage = ext4_releasepage, | |
3853 | .direct_IO = ext4_direct_IO, | |
3854 | .migratepage = buffer_migrate_page, | |
3855 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 3856 | .error_remove_page = generic_error_remove_page, |
ac27a0ec DK |
3857 | }; |
3858 | ||
617ba13b | 3859 | static const struct address_space_operations ext4_writeback_aops = { |
8ab22b9a HH |
3860 | .readpage = ext4_readpage, |
3861 | .readpages = ext4_readpages, | |
43ce1d23 | 3862 | .writepage = ext4_writepage, |
8ab22b9a HH |
3863 | .sync_page = block_sync_page, |
3864 | .write_begin = ext4_write_begin, | |
3865 | .write_end = ext4_writeback_write_end, | |
3866 | .bmap = ext4_bmap, | |
3867 | .invalidatepage = ext4_invalidatepage, | |
3868 | .releasepage = ext4_releasepage, | |
3869 | .direct_IO = ext4_direct_IO, | |
3870 | .migratepage = buffer_migrate_page, | |
3871 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 3872 | .error_remove_page = generic_error_remove_page, |
ac27a0ec DK |
3873 | }; |
3874 | ||
617ba13b | 3875 | static const struct address_space_operations ext4_journalled_aops = { |
8ab22b9a HH |
3876 | .readpage = ext4_readpage, |
3877 | .readpages = ext4_readpages, | |
43ce1d23 | 3878 | .writepage = ext4_writepage, |
8ab22b9a HH |
3879 | .sync_page = block_sync_page, |
3880 | .write_begin = ext4_write_begin, | |
3881 | .write_end = ext4_journalled_write_end, | |
3882 | .set_page_dirty = ext4_journalled_set_page_dirty, | |
3883 | .bmap = ext4_bmap, | |
3884 | .invalidatepage = ext4_invalidatepage, | |
3885 | .releasepage = ext4_releasepage, | |
3886 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 3887 | .error_remove_page = generic_error_remove_page, |
ac27a0ec DK |
3888 | }; |
3889 | ||
64769240 | 3890 | static const struct address_space_operations ext4_da_aops = { |
8ab22b9a HH |
3891 | .readpage = ext4_readpage, |
3892 | .readpages = ext4_readpages, | |
43ce1d23 | 3893 | .writepage = ext4_writepage, |
8ab22b9a HH |
3894 | .writepages = ext4_da_writepages, |
3895 | .sync_page = block_sync_page, | |
3896 | .write_begin = ext4_da_write_begin, | |
3897 | .write_end = ext4_da_write_end, | |
3898 | .bmap = ext4_bmap, | |
3899 | .invalidatepage = ext4_da_invalidatepage, | |
3900 | .releasepage = ext4_releasepage, | |
3901 | .direct_IO = ext4_direct_IO, | |
3902 | .migratepage = buffer_migrate_page, | |
3903 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 3904 | .error_remove_page = generic_error_remove_page, |
64769240 AT |
3905 | }; |
3906 | ||
617ba13b | 3907 | void ext4_set_aops(struct inode *inode) |
ac27a0ec | 3908 | { |
cd1aac32 AK |
3909 | if (ext4_should_order_data(inode) && |
3910 | test_opt(inode->i_sb, DELALLOC)) | |
3911 | inode->i_mapping->a_ops = &ext4_da_aops; | |
3912 | else if (ext4_should_order_data(inode)) | |
617ba13b | 3913 | inode->i_mapping->a_ops = &ext4_ordered_aops; |
64769240 AT |
3914 | else if (ext4_should_writeback_data(inode) && |
3915 | test_opt(inode->i_sb, DELALLOC)) | |
3916 | inode->i_mapping->a_ops = &ext4_da_aops; | |
617ba13b MC |
3917 | else if (ext4_should_writeback_data(inode)) |
3918 | inode->i_mapping->a_ops = &ext4_writeback_aops; | |
ac27a0ec | 3919 | else |
617ba13b | 3920 | inode->i_mapping->a_ops = &ext4_journalled_aops; |
ac27a0ec DK |
3921 | } |
3922 | ||
3923 | /* | |
617ba13b | 3924 | * ext4_block_truncate_page() zeroes out a mapping from file offset `from' |
ac27a0ec DK |
3925 | * up to the end of the block which corresponds to `from'. |
3926 | * This required during truncate. We need to physically zero the tail end | |
3927 | * of that block so it doesn't yield old data if the file is later grown. | |
3928 | */ | |
cf108bca | 3929 | int ext4_block_truncate_page(handle_t *handle, |
ac27a0ec DK |
3930 | struct address_space *mapping, loff_t from) |
3931 | { | |
617ba13b | 3932 | ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT; |
ac27a0ec | 3933 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
725d26d3 AK |
3934 | unsigned blocksize, length, pos; |
3935 | ext4_lblk_t iblock; | |
ac27a0ec DK |
3936 | struct inode *inode = mapping->host; |
3937 | struct buffer_head *bh; | |
cf108bca | 3938 | struct page *page; |
ac27a0ec | 3939 | int err = 0; |
ac27a0ec | 3940 | |
f4a01017 TT |
3941 | page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT, |
3942 | mapping_gfp_mask(mapping) & ~__GFP_FS); | |
cf108bca JK |
3943 | if (!page) |
3944 | return -EINVAL; | |
3945 | ||
ac27a0ec DK |
3946 | blocksize = inode->i_sb->s_blocksize; |
3947 | length = blocksize - (offset & (blocksize - 1)); | |
3948 | iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
3949 | ||
3950 | /* | |
3951 | * For "nobh" option, we can only work if we don't need to | |
3952 | * read-in the page - otherwise we create buffers to do the IO. | |
3953 | */ | |
3954 | if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && | |
617ba13b | 3955 | ext4_should_writeback_data(inode) && PageUptodate(page)) { |
eebd2aa3 | 3956 | zero_user(page, offset, length); |
ac27a0ec DK |
3957 | set_page_dirty(page); |
3958 | goto unlock; | |
3959 | } | |
3960 | ||
3961 | if (!page_has_buffers(page)) | |
3962 | create_empty_buffers(page, blocksize, 0); | |
3963 | ||
3964 | /* Find the buffer that contains "offset" */ | |
3965 | bh = page_buffers(page); | |
3966 | pos = blocksize; | |
3967 | while (offset >= pos) { | |
3968 | bh = bh->b_this_page; | |
3969 | iblock++; | |
3970 | pos += blocksize; | |
3971 | } | |
3972 | ||
3973 | err = 0; | |
3974 | if (buffer_freed(bh)) { | |
3975 | BUFFER_TRACE(bh, "freed: skip"); | |
3976 | goto unlock; | |
3977 | } | |
3978 | ||
3979 | if (!buffer_mapped(bh)) { | |
3980 | BUFFER_TRACE(bh, "unmapped"); | |
617ba13b | 3981 | ext4_get_block(inode, iblock, bh, 0); |
ac27a0ec DK |
3982 | /* unmapped? It's a hole - nothing to do */ |
3983 | if (!buffer_mapped(bh)) { | |
3984 | BUFFER_TRACE(bh, "still unmapped"); | |
3985 | goto unlock; | |
3986 | } | |
3987 | } | |
3988 | ||
3989 | /* Ok, it's mapped. Make sure it's up-to-date */ | |
3990 | if (PageUptodate(page)) | |
3991 | set_buffer_uptodate(bh); | |
3992 | ||
3993 | if (!buffer_uptodate(bh)) { | |
3994 | err = -EIO; | |
3995 | ll_rw_block(READ, 1, &bh); | |
3996 | wait_on_buffer(bh); | |
3997 | /* Uhhuh. Read error. Complain and punt. */ | |
3998 | if (!buffer_uptodate(bh)) | |
3999 | goto unlock; | |
4000 | } | |
4001 | ||
617ba13b | 4002 | if (ext4_should_journal_data(inode)) { |
ac27a0ec | 4003 | BUFFER_TRACE(bh, "get write access"); |
617ba13b | 4004 | err = ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
4005 | if (err) |
4006 | goto unlock; | |
4007 | } | |
4008 | ||
eebd2aa3 | 4009 | zero_user(page, offset, length); |
ac27a0ec DK |
4010 | |
4011 | BUFFER_TRACE(bh, "zeroed end of block"); | |
4012 | ||
4013 | err = 0; | |
617ba13b | 4014 | if (ext4_should_journal_data(inode)) { |
0390131b | 4015 | err = ext4_handle_dirty_metadata(handle, inode, bh); |
ac27a0ec | 4016 | } else { |
617ba13b | 4017 | if (ext4_should_order_data(inode)) |
678aaf48 | 4018 | err = ext4_jbd2_file_inode(handle, inode); |
ac27a0ec DK |
4019 | mark_buffer_dirty(bh); |
4020 | } | |
4021 | ||
4022 | unlock: | |
4023 | unlock_page(page); | |
4024 | page_cache_release(page); | |
4025 | return err; | |
4026 | } | |
4027 | ||
4028 | /* | |
4029 | * Probably it should be a library function... search for first non-zero word | |
4030 | * or memcmp with zero_page, whatever is better for particular architecture. | |
4031 | * Linus? | |
4032 | */ | |
4033 | static inline int all_zeroes(__le32 *p, __le32 *q) | |
4034 | { | |
4035 | while (p < q) | |
4036 | if (*p++) | |
4037 | return 0; | |
4038 | return 1; | |
4039 | } | |
4040 | ||
4041 | /** | |
617ba13b | 4042 | * ext4_find_shared - find the indirect blocks for partial truncation. |
ac27a0ec DK |
4043 | * @inode: inode in question |
4044 | * @depth: depth of the affected branch | |
617ba13b | 4045 | * @offsets: offsets of pointers in that branch (see ext4_block_to_path) |
ac27a0ec DK |
4046 | * @chain: place to store the pointers to partial indirect blocks |
4047 | * @top: place to the (detached) top of branch | |
4048 | * | |
617ba13b | 4049 | * This is a helper function used by ext4_truncate(). |
ac27a0ec DK |
4050 | * |
4051 | * When we do truncate() we may have to clean the ends of several | |
4052 | * indirect blocks but leave the blocks themselves alive. Block is | |
4053 | * partially truncated if some data below the new i_size is refered | |
4054 | * from it (and it is on the path to the first completely truncated | |
4055 | * data block, indeed). We have to free the top of that path along | |
4056 | * with everything to the right of the path. Since no allocation | |
617ba13b | 4057 | * past the truncation point is possible until ext4_truncate() |
ac27a0ec DK |
4058 | * finishes, we may safely do the latter, but top of branch may |
4059 | * require special attention - pageout below the truncation point | |
4060 | * might try to populate it. | |
4061 | * | |
4062 | * We atomically detach the top of branch from the tree, store the | |
4063 | * block number of its root in *@top, pointers to buffer_heads of | |
4064 | * partially truncated blocks - in @chain[].bh and pointers to | |
4065 | * their last elements that should not be removed - in | |
4066 | * @chain[].p. Return value is the pointer to last filled element | |
4067 | * of @chain. | |
4068 | * | |
4069 | * The work left to caller to do the actual freeing of subtrees: | |
4070 | * a) free the subtree starting from *@top | |
4071 | * b) free the subtrees whose roots are stored in | |
4072 | * (@chain[i].p+1 .. end of @chain[i].bh->b_data) | |
4073 | * c) free the subtrees growing from the inode past the @chain[0]. | |
4074 | * (no partially truncated stuff there). */ | |
4075 | ||
617ba13b | 4076 | static Indirect *ext4_find_shared(struct inode *inode, int depth, |
de9a55b8 TT |
4077 | ext4_lblk_t offsets[4], Indirect chain[4], |
4078 | __le32 *top) | |
ac27a0ec DK |
4079 | { |
4080 | Indirect *partial, *p; | |
4081 | int k, err; | |
4082 | ||
4083 | *top = 0; | |
bf48aabb | 4084 | /* Make k index the deepest non-null offset + 1 */ |
ac27a0ec DK |
4085 | for (k = depth; k > 1 && !offsets[k-1]; k--) |
4086 | ; | |
617ba13b | 4087 | partial = ext4_get_branch(inode, k, offsets, chain, &err); |
ac27a0ec DK |
4088 | /* Writer: pointers */ |
4089 | if (!partial) | |
4090 | partial = chain + k-1; | |
4091 | /* | |
4092 | * If the branch acquired continuation since we've looked at it - | |
4093 | * fine, it should all survive and (new) top doesn't belong to us. | |
4094 | */ | |
4095 | if (!partial->key && *partial->p) | |
4096 | /* Writer: end */ | |
4097 | goto no_top; | |
af5bc92d | 4098 | for (p = partial; (p > chain) && all_zeroes((__le32 *) p->bh->b_data, p->p); p--) |
ac27a0ec DK |
4099 | ; |
4100 | /* | |
4101 | * OK, we've found the last block that must survive. The rest of our | |
4102 | * branch should be detached before unlocking. However, if that rest | |
4103 | * of branch is all ours and does not grow immediately from the inode | |
4104 | * it's easier to cheat and just decrement partial->p. | |
4105 | */ | |
4106 | if (p == chain + k - 1 && p > chain) { | |
4107 | p->p--; | |
4108 | } else { | |
4109 | *top = *p->p; | |
617ba13b | 4110 | /* Nope, don't do this in ext4. Must leave the tree intact */ |
ac27a0ec DK |
4111 | #if 0 |
4112 | *p->p = 0; | |
4113 | #endif | |
4114 | } | |
4115 | /* Writer: end */ | |
4116 | ||
af5bc92d | 4117 | while (partial > p) { |
ac27a0ec DK |
4118 | brelse(partial->bh); |
4119 | partial--; | |
4120 | } | |
4121 | no_top: | |
4122 | return partial; | |
4123 | } | |
4124 | ||
4125 | /* | |
4126 | * Zero a number of block pointers in either an inode or an indirect block. | |
4127 | * If we restart the transaction we must again get write access to the | |
4128 | * indirect block for further modification. | |
4129 | * | |
4130 | * We release `count' blocks on disk, but (last - first) may be greater | |
4131 | * than `count' because there can be holes in there. | |
4132 | */ | |
617ba13b | 4133 | static void ext4_clear_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
4134 | struct buffer_head *bh, |
4135 | ext4_fsblk_t block_to_free, | |
4136 | unsigned long count, __le32 *first, | |
4137 | __le32 *last) | |
ac27a0ec DK |
4138 | { |
4139 | __le32 *p; | |
e6362609 TT |
4140 | int flags = EXT4_FREE_BLOCKS_FORGET; |
4141 | ||
4142 | if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) | |
4143 | flags |= EXT4_FREE_BLOCKS_METADATA; | |
50689696 | 4144 | |
ac27a0ec DK |
4145 | if (try_to_extend_transaction(handle, inode)) { |
4146 | if (bh) { | |
0390131b FM |
4147 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
4148 | ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec | 4149 | } |
617ba13b | 4150 | ext4_mark_inode_dirty(handle, inode); |
487caeef JK |
4151 | ext4_truncate_restart_trans(handle, inode, |
4152 | blocks_for_truncate(inode)); | |
ac27a0ec DK |
4153 | if (bh) { |
4154 | BUFFER_TRACE(bh, "retaking write access"); | |
617ba13b | 4155 | ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
4156 | } |
4157 | } | |
4158 | ||
e6362609 TT |
4159 | for (p = first; p < last; p++) |
4160 | *p = 0; | |
ac27a0ec | 4161 | |
e6362609 | 4162 | ext4_free_blocks(handle, inode, 0, block_to_free, count, flags); |
ac27a0ec DK |
4163 | } |
4164 | ||
4165 | /** | |
617ba13b | 4166 | * ext4_free_data - free a list of data blocks |
ac27a0ec DK |
4167 | * @handle: handle for this transaction |
4168 | * @inode: inode we are dealing with | |
4169 | * @this_bh: indirect buffer_head which contains *@first and *@last | |
4170 | * @first: array of block numbers | |
4171 | * @last: points immediately past the end of array | |
4172 | * | |
4173 | * We are freeing all blocks refered from that array (numbers are stored as | |
4174 | * little-endian 32-bit) and updating @inode->i_blocks appropriately. | |
4175 | * | |
4176 | * We accumulate contiguous runs of blocks to free. Conveniently, if these | |
4177 | * blocks are contiguous then releasing them at one time will only affect one | |
4178 | * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't | |
4179 | * actually use a lot of journal space. | |
4180 | * | |
4181 | * @this_bh will be %NULL if @first and @last point into the inode's direct | |
4182 | * block pointers. | |
4183 | */ | |
617ba13b | 4184 | static void ext4_free_data(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
4185 | struct buffer_head *this_bh, |
4186 | __le32 *first, __le32 *last) | |
4187 | { | |
617ba13b | 4188 | ext4_fsblk_t block_to_free = 0; /* Starting block # of a run */ |
ac27a0ec DK |
4189 | unsigned long count = 0; /* Number of blocks in the run */ |
4190 | __le32 *block_to_free_p = NULL; /* Pointer into inode/ind | |
4191 | corresponding to | |
4192 | block_to_free */ | |
617ba13b | 4193 | ext4_fsblk_t nr; /* Current block # */ |
ac27a0ec DK |
4194 | __le32 *p; /* Pointer into inode/ind |
4195 | for current block */ | |
4196 | int err; | |
4197 | ||
4198 | if (this_bh) { /* For indirect block */ | |
4199 | BUFFER_TRACE(this_bh, "get_write_access"); | |
617ba13b | 4200 | err = ext4_journal_get_write_access(handle, this_bh); |
ac27a0ec DK |
4201 | /* Important: if we can't update the indirect pointers |
4202 | * to the blocks, we can't free them. */ | |
4203 | if (err) | |
4204 | return; | |
4205 | } | |
4206 | ||
4207 | for (p = first; p < last; p++) { | |
4208 | nr = le32_to_cpu(*p); | |
4209 | if (nr) { | |
4210 | /* accumulate blocks to free if they're contiguous */ | |
4211 | if (count == 0) { | |
4212 | block_to_free = nr; | |
4213 | block_to_free_p = p; | |
4214 | count = 1; | |
4215 | } else if (nr == block_to_free + count) { | |
4216 | count++; | |
4217 | } else { | |
617ba13b | 4218 | ext4_clear_blocks(handle, inode, this_bh, |
ac27a0ec DK |
4219 | block_to_free, |
4220 | count, block_to_free_p, p); | |
4221 | block_to_free = nr; | |
4222 | block_to_free_p = p; | |
4223 | count = 1; | |
4224 | } | |
4225 | } | |
4226 | } | |
4227 | ||
4228 | if (count > 0) | |
617ba13b | 4229 | ext4_clear_blocks(handle, inode, this_bh, block_to_free, |
ac27a0ec DK |
4230 | count, block_to_free_p, p); |
4231 | ||
4232 | if (this_bh) { | |
0390131b | 4233 | BUFFER_TRACE(this_bh, "call ext4_handle_dirty_metadata"); |
71dc8fbc DG |
4234 | |
4235 | /* | |
4236 | * The buffer head should have an attached journal head at this | |
4237 | * point. However, if the data is corrupted and an indirect | |
4238 | * block pointed to itself, it would have been detached when | |
4239 | * the block was cleared. Check for this instead of OOPSing. | |
4240 | */ | |
e7f07968 | 4241 | if ((EXT4_JOURNAL(inode) == NULL) || bh2jh(this_bh)) |
0390131b | 4242 | ext4_handle_dirty_metadata(handle, inode, this_bh); |
71dc8fbc DG |
4243 | else |
4244 | ext4_error(inode->i_sb, __func__, | |
4245 | "circular indirect block detected, " | |
4246 | "inode=%lu, block=%llu", | |
4247 | inode->i_ino, | |
4248 | (unsigned long long) this_bh->b_blocknr); | |
ac27a0ec DK |
4249 | } |
4250 | } | |
4251 | ||
4252 | /** | |
617ba13b | 4253 | * ext4_free_branches - free an array of branches |
ac27a0ec DK |
4254 | * @handle: JBD handle for this transaction |
4255 | * @inode: inode we are dealing with | |
4256 | * @parent_bh: the buffer_head which contains *@first and *@last | |
4257 | * @first: array of block numbers | |
4258 | * @last: pointer immediately past the end of array | |
4259 | * @depth: depth of the branches to free | |
4260 | * | |
4261 | * We are freeing all blocks refered from these branches (numbers are | |
4262 | * stored as little-endian 32-bit) and updating @inode->i_blocks | |
4263 | * appropriately. | |
4264 | */ | |
617ba13b | 4265 | static void ext4_free_branches(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
4266 | struct buffer_head *parent_bh, |
4267 | __le32 *first, __le32 *last, int depth) | |
4268 | { | |
617ba13b | 4269 | ext4_fsblk_t nr; |
ac27a0ec DK |
4270 | __le32 *p; |
4271 | ||
0390131b | 4272 | if (ext4_handle_is_aborted(handle)) |
ac27a0ec DK |
4273 | return; |
4274 | ||
4275 | if (depth--) { | |
4276 | struct buffer_head *bh; | |
617ba13b | 4277 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
ac27a0ec DK |
4278 | p = last; |
4279 | while (--p >= first) { | |
4280 | nr = le32_to_cpu(*p); | |
4281 | if (!nr) | |
4282 | continue; /* A hole */ | |
4283 | ||
4284 | /* Go read the buffer for the next level down */ | |
4285 | bh = sb_bread(inode->i_sb, nr); | |
4286 | ||
4287 | /* | |
4288 | * A read failure? Report error and clear slot | |
4289 | * (should be rare). | |
4290 | */ | |
4291 | if (!bh) { | |
617ba13b | 4292 | ext4_error(inode->i_sb, "ext4_free_branches", |
2ae02107 | 4293 | "Read failure, inode=%lu, block=%llu", |
ac27a0ec DK |
4294 | inode->i_ino, nr); |
4295 | continue; | |
4296 | } | |
4297 | ||
4298 | /* This zaps the entire block. Bottom up. */ | |
4299 | BUFFER_TRACE(bh, "free child branches"); | |
617ba13b | 4300 | ext4_free_branches(handle, inode, bh, |
af5bc92d TT |
4301 | (__le32 *) bh->b_data, |
4302 | (__le32 *) bh->b_data + addr_per_block, | |
4303 | depth); | |
ac27a0ec DK |
4304 | |
4305 | /* | |
4306 | * We've probably journalled the indirect block several | |
4307 | * times during the truncate. But it's no longer | |
4308 | * needed and we now drop it from the transaction via | |
dab291af | 4309 | * jbd2_journal_revoke(). |
ac27a0ec DK |
4310 | * |
4311 | * That's easy if it's exclusively part of this | |
4312 | * transaction. But if it's part of the committing | |
dab291af | 4313 | * transaction then jbd2_journal_forget() will simply |
ac27a0ec | 4314 | * brelse() it. That means that if the underlying |
617ba13b | 4315 | * block is reallocated in ext4_get_block(), |
ac27a0ec DK |
4316 | * unmap_underlying_metadata() will find this block |
4317 | * and will try to get rid of it. damn, damn. | |
4318 | * | |
4319 | * If this block has already been committed to the | |
4320 | * journal, a revoke record will be written. And | |
4321 | * revoke records must be emitted *before* clearing | |
4322 | * this block's bit in the bitmaps. | |
4323 | */ | |
617ba13b | 4324 | ext4_forget(handle, 1, inode, bh, bh->b_blocknr); |
ac27a0ec DK |
4325 | |
4326 | /* | |
4327 | * Everything below this this pointer has been | |
4328 | * released. Now let this top-of-subtree go. | |
4329 | * | |
4330 | * We want the freeing of this indirect block to be | |
4331 | * atomic in the journal with the updating of the | |
4332 | * bitmap block which owns it. So make some room in | |
4333 | * the journal. | |
4334 | * | |
4335 | * We zero the parent pointer *after* freeing its | |
4336 | * pointee in the bitmaps, so if extend_transaction() | |
4337 | * for some reason fails to put the bitmap changes and | |
4338 | * the release into the same transaction, recovery | |
4339 | * will merely complain about releasing a free block, | |
4340 | * rather than leaking blocks. | |
4341 | */ | |
0390131b | 4342 | if (ext4_handle_is_aborted(handle)) |
ac27a0ec DK |
4343 | return; |
4344 | if (try_to_extend_transaction(handle, inode)) { | |
617ba13b | 4345 | ext4_mark_inode_dirty(handle, inode); |
487caeef JK |
4346 | ext4_truncate_restart_trans(handle, inode, |
4347 | blocks_for_truncate(inode)); | |
ac27a0ec DK |
4348 | } |
4349 | ||
e6362609 TT |
4350 | ext4_free_blocks(handle, inode, 0, nr, 1, |
4351 | EXT4_FREE_BLOCKS_METADATA); | |
ac27a0ec DK |
4352 | |
4353 | if (parent_bh) { | |
4354 | /* | |
4355 | * The block which we have just freed is | |
4356 | * pointed to by an indirect block: journal it | |
4357 | */ | |
4358 | BUFFER_TRACE(parent_bh, "get_write_access"); | |
617ba13b | 4359 | if (!ext4_journal_get_write_access(handle, |
ac27a0ec DK |
4360 | parent_bh)){ |
4361 | *p = 0; | |
4362 | BUFFER_TRACE(parent_bh, | |
0390131b FM |
4363 | "call ext4_handle_dirty_metadata"); |
4364 | ext4_handle_dirty_metadata(handle, | |
4365 | inode, | |
4366 | parent_bh); | |
ac27a0ec DK |
4367 | } |
4368 | } | |
4369 | } | |
4370 | } else { | |
4371 | /* We have reached the bottom of the tree. */ | |
4372 | BUFFER_TRACE(parent_bh, "free data blocks"); | |
617ba13b | 4373 | ext4_free_data(handle, inode, parent_bh, first, last); |
ac27a0ec DK |
4374 | } |
4375 | } | |
4376 | ||
91ef4caf DG |
4377 | int ext4_can_truncate(struct inode *inode) |
4378 | { | |
4379 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | |
4380 | return 0; | |
4381 | if (S_ISREG(inode->i_mode)) | |
4382 | return 1; | |
4383 | if (S_ISDIR(inode->i_mode)) | |
4384 | return 1; | |
4385 | if (S_ISLNK(inode->i_mode)) | |
4386 | return !ext4_inode_is_fast_symlink(inode); | |
4387 | return 0; | |
4388 | } | |
4389 | ||
ac27a0ec | 4390 | /* |
617ba13b | 4391 | * ext4_truncate() |
ac27a0ec | 4392 | * |
617ba13b MC |
4393 | * We block out ext4_get_block() block instantiations across the entire |
4394 | * transaction, and VFS/VM ensures that ext4_truncate() cannot run | |
ac27a0ec DK |
4395 | * simultaneously on behalf of the same inode. |
4396 | * | |
4397 | * As we work through the truncate and commmit bits of it to the journal there | |
4398 | * is one core, guiding principle: the file's tree must always be consistent on | |
4399 | * disk. We must be able to restart the truncate after a crash. | |
4400 | * | |
4401 | * The file's tree may be transiently inconsistent in memory (although it | |
4402 | * probably isn't), but whenever we close off and commit a journal transaction, | |
4403 | * the contents of (the filesystem + the journal) must be consistent and | |
4404 | * restartable. It's pretty simple, really: bottom up, right to left (although | |
4405 | * left-to-right works OK too). | |
4406 | * | |
4407 | * Note that at recovery time, journal replay occurs *before* the restart of | |
4408 | * truncate against the orphan inode list. | |
4409 | * | |
4410 | * The committed inode has the new, desired i_size (which is the same as | |
617ba13b | 4411 | * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see |
ac27a0ec | 4412 | * that this inode's truncate did not complete and it will again call |
617ba13b MC |
4413 | * ext4_truncate() to have another go. So there will be instantiated blocks |
4414 | * to the right of the truncation point in a crashed ext4 filesystem. But | |
ac27a0ec | 4415 | * that's fine - as long as they are linked from the inode, the post-crash |
617ba13b | 4416 | * ext4_truncate() run will find them and release them. |
ac27a0ec | 4417 | */ |
617ba13b | 4418 | void ext4_truncate(struct inode *inode) |
ac27a0ec DK |
4419 | { |
4420 | handle_t *handle; | |
617ba13b | 4421 | struct ext4_inode_info *ei = EXT4_I(inode); |
ac27a0ec | 4422 | __le32 *i_data = ei->i_data; |
617ba13b | 4423 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
ac27a0ec | 4424 | struct address_space *mapping = inode->i_mapping; |
725d26d3 | 4425 | ext4_lblk_t offsets[4]; |
ac27a0ec DK |
4426 | Indirect chain[4]; |
4427 | Indirect *partial; | |
4428 | __le32 nr = 0; | |
4429 | int n; | |
725d26d3 | 4430 | ext4_lblk_t last_block; |
ac27a0ec | 4431 | unsigned blocksize = inode->i_sb->s_blocksize; |
ac27a0ec | 4432 | |
91ef4caf | 4433 | if (!ext4_can_truncate(inode)) |
ac27a0ec DK |
4434 | return; |
4435 | ||
5534fb5b | 4436 | if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC)) |
7d8f9f7d TT |
4437 | ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE; |
4438 | ||
1d03ec98 | 4439 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
cf108bca | 4440 | ext4_ext_truncate(inode); |
1d03ec98 AK |
4441 | return; |
4442 | } | |
a86c6181 | 4443 | |
ac27a0ec | 4444 | handle = start_transaction(inode); |
cf108bca | 4445 | if (IS_ERR(handle)) |
ac27a0ec | 4446 | return; /* AKPM: return what? */ |
ac27a0ec DK |
4447 | |
4448 | last_block = (inode->i_size + blocksize-1) | |
617ba13b | 4449 | >> EXT4_BLOCK_SIZE_BITS(inode->i_sb); |
ac27a0ec | 4450 | |
cf108bca JK |
4451 | if (inode->i_size & (blocksize - 1)) |
4452 | if (ext4_block_truncate_page(handle, mapping, inode->i_size)) | |
4453 | goto out_stop; | |
ac27a0ec | 4454 | |
617ba13b | 4455 | n = ext4_block_to_path(inode, last_block, offsets, NULL); |
ac27a0ec DK |
4456 | if (n == 0) |
4457 | goto out_stop; /* error */ | |
4458 | ||
4459 | /* | |
4460 | * OK. This truncate is going to happen. We add the inode to the | |
4461 | * orphan list, so that if this truncate spans multiple transactions, | |
4462 | * and we crash, we will resume the truncate when the filesystem | |
4463 | * recovers. It also marks the inode dirty, to catch the new size. | |
4464 | * | |
4465 | * Implication: the file must always be in a sane, consistent | |
4466 | * truncatable state while each transaction commits. | |
4467 | */ | |
617ba13b | 4468 | if (ext4_orphan_add(handle, inode)) |
ac27a0ec DK |
4469 | goto out_stop; |
4470 | ||
632eaeab MC |
4471 | /* |
4472 | * From here we block out all ext4_get_block() callers who want to | |
4473 | * modify the block allocation tree. | |
4474 | */ | |
4475 | down_write(&ei->i_data_sem); | |
b4df2030 | 4476 | |
c2ea3fde | 4477 | ext4_discard_preallocations(inode); |
b4df2030 | 4478 | |
ac27a0ec DK |
4479 | /* |
4480 | * The orphan list entry will now protect us from any crash which | |
4481 | * occurs before the truncate completes, so it is now safe to propagate | |
4482 | * the new, shorter inode size (held for now in i_size) into the | |
4483 | * on-disk inode. We do this via i_disksize, which is the value which | |
617ba13b | 4484 | * ext4 *really* writes onto the disk inode. |
ac27a0ec DK |
4485 | */ |
4486 | ei->i_disksize = inode->i_size; | |
4487 | ||
ac27a0ec | 4488 | if (n == 1) { /* direct blocks */ |
617ba13b MC |
4489 | ext4_free_data(handle, inode, NULL, i_data+offsets[0], |
4490 | i_data + EXT4_NDIR_BLOCKS); | |
ac27a0ec DK |
4491 | goto do_indirects; |
4492 | } | |
4493 | ||
617ba13b | 4494 | partial = ext4_find_shared(inode, n, offsets, chain, &nr); |
ac27a0ec DK |
4495 | /* Kill the top of shared branch (not detached) */ |
4496 | if (nr) { | |
4497 | if (partial == chain) { | |
4498 | /* Shared branch grows from the inode */ | |
617ba13b | 4499 | ext4_free_branches(handle, inode, NULL, |
ac27a0ec DK |
4500 | &nr, &nr+1, (chain+n-1) - partial); |
4501 | *partial->p = 0; | |
4502 | /* | |
4503 | * We mark the inode dirty prior to restart, | |
4504 | * and prior to stop. No need for it here. | |
4505 | */ | |
4506 | } else { | |
4507 | /* Shared branch grows from an indirect block */ | |
4508 | BUFFER_TRACE(partial->bh, "get_write_access"); | |
617ba13b | 4509 | ext4_free_branches(handle, inode, partial->bh, |
ac27a0ec DK |
4510 | partial->p, |
4511 | partial->p+1, (chain+n-1) - partial); | |
4512 | } | |
4513 | } | |
4514 | /* Clear the ends of indirect blocks on the shared branch */ | |
4515 | while (partial > chain) { | |
617ba13b | 4516 | ext4_free_branches(handle, inode, partial->bh, partial->p + 1, |
ac27a0ec DK |
4517 | (__le32*)partial->bh->b_data+addr_per_block, |
4518 | (chain+n-1) - partial); | |
4519 | BUFFER_TRACE(partial->bh, "call brelse"); | |
de9a55b8 | 4520 | brelse(partial->bh); |
ac27a0ec DK |
4521 | partial--; |
4522 | } | |
4523 | do_indirects: | |
4524 | /* Kill the remaining (whole) subtrees */ | |
4525 | switch (offsets[0]) { | |
4526 | default: | |
617ba13b | 4527 | nr = i_data[EXT4_IND_BLOCK]; |
ac27a0ec | 4528 | if (nr) { |
617ba13b MC |
4529 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); |
4530 | i_data[EXT4_IND_BLOCK] = 0; | |
ac27a0ec | 4531 | } |
617ba13b MC |
4532 | case EXT4_IND_BLOCK: |
4533 | nr = i_data[EXT4_DIND_BLOCK]; | |
ac27a0ec | 4534 | if (nr) { |
617ba13b MC |
4535 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); |
4536 | i_data[EXT4_DIND_BLOCK] = 0; | |
ac27a0ec | 4537 | } |
617ba13b MC |
4538 | case EXT4_DIND_BLOCK: |
4539 | nr = i_data[EXT4_TIND_BLOCK]; | |
ac27a0ec | 4540 | if (nr) { |
617ba13b MC |
4541 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); |
4542 | i_data[EXT4_TIND_BLOCK] = 0; | |
ac27a0ec | 4543 | } |
617ba13b | 4544 | case EXT4_TIND_BLOCK: |
ac27a0ec DK |
4545 | ; |
4546 | } | |
4547 | ||
0e855ac8 | 4548 | up_write(&ei->i_data_sem); |
ef7f3835 | 4549 | inode->i_mtime = inode->i_ctime = ext4_current_time(inode); |
617ba13b | 4550 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
4551 | |
4552 | /* | |
4553 | * In a multi-transaction truncate, we only make the final transaction | |
4554 | * synchronous | |
4555 | */ | |
4556 | if (IS_SYNC(inode)) | |
0390131b | 4557 | ext4_handle_sync(handle); |
ac27a0ec DK |
4558 | out_stop: |
4559 | /* | |
4560 | * If this was a simple ftruncate(), and the file will remain alive | |
4561 | * then we need to clear up the orphan record which we created above. | |
4562 | * However, if this was a real unlink then we were called by | |
617ba13b | 4563 | * ext4_delete_inode(), and we allow that function to clean up the |
ac27a0ec DK |
4564 | * orphan info for us. |
4565 | */ | |
4566 | if (inode->i_nlink) | |
617ba13b | 4567 | ext4_orphan_del(handle, inode); |
ac27a0ec | 4568 | |
617ba13b | 4569 | ext4_journal_stop(handle); |
ac27a0ec DK |
4570 | } |
4571 | ||
ac27a0ec | 4572 | /* |
617ba13b | 4573 | * ext4_get_inode_loc returns with an extra refcount against the inode's |
ac27a0ec DK |
4574 | * underlying buffer_head on success. If 'in_mem' is true, we have all |
4575 | * data in memory that is needed to recreate the on-disk version of this | |
4576 | * inode. | |
4577 | */ | |
617ba13b MC |
4578 | static int __ext4_get_inode_loc(struct inode *inode, |
4579 | struct ext4_iloc *iloc, int in_mem) | |
ac27a0ec | 4580 | { |
240799cd TT |
4581 | struct ext4_group_desc *gdp; |
4582 | struct buffer_head *bh; | |
4583 | struct super_block *sb = inode->i_sb; | |
4584 | ext4_fsblk_t block; | |
4585 | int inodes_per_block, inode_offset; | |
4586 | ||
3a06d778 | 4587 | iloc->bh = NULL; |
240799cd TT |
4588 | if (!ext4_valid_inum(sb, inode->i_ino)) |
4589 | return -EIO; | |
ac27a0ec | 4590 | |
240799cd TT |
4591 | iloc->block_group = (inode->i_ino - 1) / EXT4_INODES_PER_GROUP(sb); |
4592 | gdp = ext4_get_group_desc(sb, iloc->block_group, NULL); | |
4593 | if (!gdp) | |
ac27a0ec DK |
4594 | return -EIO; |
4595 | ||
240799cd TT |
4596 | /* |
4597 | * Figure out the offset within the block group inode table | |
4598 | */ | |
4599 | inodes_per_block = (EXT4_BLOCK_SIZE(sb) / EXT4_INODE_SIZE(sb)); | |
4600 | inode_offset = ((inode->i_ino - 1) % | |
4601 | EXT4_INODES_PER_GROUP(sb)); | |
4602 | block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block); | |
4603 | iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb); | |
4604 | ||
4605 | bh = sb_getblk(sb, block); | |
ac27a0ec | 4606 | if (!bh) { |
240799cd TT |
4607 | ext4_error(sb, "ext4_get_inode_loc", "unable to read " |
4608 | "inode block - inode=%lu, block=%llu", | |
4609 | inode->i_ino, block); | |
ac27a0ec DK |
4610 | return -EIO; |
4611 | } | |
4612 | if (!buffer_uptodate(bh)) { | |
4613 | lock_buffer(bh); | |
9c83a923 HK |
4614 | |
4615 | /* | |
4616 | * If the buffer has the write error flag, we have failed | |
4617 | * to write out another inode in the same block. In this | |
4618 | * case, we don't have to read the block because we may | |
4619 | * read the old inode data successfully. | |
4620 | */ | |
4621 | if (buffer_write_io_error(bh) && !buffer_uptodate(bh)) | |
4622 | set_buffer_uptodate(bh); | |
4623 | ||
ac27a0ec DK |
4624 | if (buffer_uptodate(bh)) { |
4625 | /* someone brought it uptodate while we waited */ | |
4626 | unlock_buffer(bh); | |
4627 | goto has_buffer; | |
4628 | } | |
4629 | ||
4630 | /* | |
4631 | * If we have all information of the inode in memory and this | |
4632 | * is the only valid inode in the block, we need not read the | |
4633 | * block. | |
4634 | */ | |
4635 | if (in_mem) { | |
4636 | struct buffer_head *bitmap_bh; | |
240799cd | 4637 | int i, start; |
ac27a0ec | 4638 | |
240799cd | 4639 | start = inode_offset & ~(inodes_per_block - 1); |
ac27a0ec | 4640 | |
240799cd TT |
4641 | /* Is the inode bitmap in cache? */ |
4642 | bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp)); | |
ac27a0ec DK |
4643 | if (!bitmap_bh) |
4644 | goto make_io; | |
4645 | ||
4646 | /* | |
4647 | * If the inode bitmap isn't in cache then the | |
4648 | * optimisation may end up performing two reads instead | |
4649 | * of one, so skip it. | |
4650 | */ | |
4651 | if (!buffer_uptodate(bitmap_bh)) { | |
4652 | brelse(bitmap_bh); | |
4653 | goto make_io; | |
4654 | } | |
240799cd | 4655 | for (i = start; i < start + inodes_per_block; i++) { |
ac27a0ec DK |
4656 | if (i == inode_offset) |
4657 | continue; | |
617ba13b | 4658 | if (ext4_test_bit(i, bitmap_bh->b_data)) |
ac27a0ec DK |
4659 | break; |
4660 | } | |
4661 | brelse(bitmap_bh); | |
240799cd | 4662 | if (i == start + inodes_per_block) { |
ac27a0ec DK |
4663 | /* all other inodes are free, so skip I/O */ |
4664 | memset(bh->b_data, 0, bh->b_size); | |
4665 | set_buffer_uptodate(bh); | |
4666 | unlock_buffer(bh); | |
4667 | goto has_buffer; | |
4668 | } | |
4669 | } | |
4670 | ||
4671 | make_io: | |
240799cd TT |
4672 | /* |
4673 | * If we need to do any I/O, try to pre-readahead extra | |
4674 | * blocks from the inode table. | |
4675 | */ | |
4676 | if (EXT4_SB(sb)->s_inode_readahead_blks) { | |
4677 | ext4_fsblk_t b, end, table; | |
4678 | unsigned num; | |
4679 | ||
4680 | table = ext4_inode_table(sb, gdp); | |
b713a5ec | 4681 | /* s_inode_readahead_blks is always a power of 2 */ |
240799cd TT |
4682 | b = block & ~(EXT4_SB(sb)->s_inode_readahead_blks-1); |
4683 | if (table > b) | |
4684 | b = table; | |
4685 | end = b + EXT4_SB(sb)->s_inode_readahead_blks; | |
4686 | num = EXT4_INODES_PER_GROUP(sb); | |
4687 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4688 | EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) | |
560671a0 | 4689 | num -= ext4_itable_unused_count(sb, gdp); |
240799cd TT |
4690 | table += num / inodes_per_block; |
4691 | if (end > table) | |
4692 | end = table; | |
4693 | while (b <= end) | |
4694 | sb_breadahead(sb, b++); | |
4695 | } | |
4696 | ||
ac27a0ec DK |
4697 | /* |
4698 | * There are other valid inodes in the buffer, this inode | |
4699 | * has in-inode xattrs, or we don't have this inode in memory. | |
4700 | * Read the block from disk. | |
4701 | */ | |
4702 | get_bh(bh); | |
4703 | bh->b_end_io = end_buffer_read_sync; | |
4704 | submit_bh(READ_META, bh); | |
4705 | wait_on_buffer(bh); | |
4706 | if (!buffer_uptodate(bh)) { | |
240799cd TT |
4707 | ext4_error(sb, __func__, |
4708 | "unable to read inode block - inode=%lu, " | |
4709 | "block=%llu", inode->i_ino, block); | |
ac27a0ec DK |
4710 | brelse(bh); |
4711 | return -EIO; | |
4712 | } | |
4713 | } | |
4714 | has_buffer: | |
4715 | iloc->bh = bh; | |
4716 | return 0; | |
4717 | } | |
4718 | ||
617ba13b | 4719 | int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) |
ac27a0ec DK |
4720 | { |
4721 | /* We have all inode data except xattrs in memory here. */ | |
617ba13b MC |
4722 | return __ext4_get_inode_loc(inode, iloc, |
4723 | !(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)); | |
ac27a0ec DK |
4724 | } |
4725 | ||
617ba13b | 4726 | void ext4_set_inode_flags(struct inode *inode) |
ac27a0ec | 4727 | { |
617ba13b | 4728 | unsigned int flags = EXT4_I(inode)->i_flags; |
ac27a0ec DK |
4729 | |
4730 | inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); | |
617ba13b | 4731 | if (flags & EXT4_SYNC_FL) |
ac27a0ec | 4732 | inode->i_flags |= S_SYNC; |
617ba13b | 4733 | if (flags & EXT4_APPEND_FL) |
ac27a0ec | 4734 | inode->i_flags |= S_APPEND; |
617ba13b | 4735 | if (flags & EXT4_IMMUTABLE_FL) |
ac27a0ec | 4736 | inode->i_flags |= S_IMMUTABLE; |
617ba13b | 4737 | if (flags & EXT4_NOATIME_FL) |
ac27a0ec | 4738 | inode->i_flags |= S_NOATIME; |
617ba13b | 4739 | if (flags & EXT4_DIRSYNC_FL) |
ac27a0ec DK |
4740 | inode->i_flags |= S_DIRSYNC; |
4741 | } | |
4742 | ||
ff9ddf7e JK |
4743 | /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */ |
4744 | void ext4_get_inode_flags(struct ext4_inode_info *ei) | |
4745 | { | |
4746 | unsigned int flags = ei->vfs_inode.i_flags; | |
4747 | ||
4748 | ei->i_flags &= ~(EXT4_SYNC_FL|EXT4_APPEND_FL| | |
4749 | EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|EXT4_DIRSYNC_FL); | |
4750 | if (flags & S_SYNC) | |
4751 | ei->i_flags |= EXT4_SYNC_FL; | |
4752 | if (flags & S_APPEND) | |
4753 | ei->i_flags |= EXT4_APPEND_FL; | |
4754 | if (flags & S_IMMUTABLE) | |
4755 | ei->i_flags |= EXT4_IMMUTABLE_FL; | |
4756 | if (flags & S_NOATIME) | |
4757 | ei->i_flags |= EXT4_NOATIME_FL; | |
4758 | if (flags & S_DIRSYNC) | |
4759 | ei->i_flags |= EXT4_DIRSYNC_FL; | |
4760 | } | |
de9a55b8 | 4761 | |
0fc1b451 | 4762 | static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode, |
de9a55b8 | 4763 | struct ext4_inode_info *ei) |
0fc1b451 AK |
4764 | { |
4765 | blkcnt_t i_blocks ; | |
8180a562 AK |
4766 | struct inode *inode = &(ei->vfs_inode); |
4767 | struct super_block *sb = inode->i_sb; | |
0fc1b451 AK |
4768 | |
4769 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4770 | EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) { | |
4771 | /* we are using combined 48 bit field */ | |
4772 | i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 | | |
4773 | le32_to_cpu(raw_inode->i_blocks_lo); | |
8180a562 AK |
4774 | if (ei->i_flags & EXT4_HUGE_FILE_FL) { |
4775 | /* i_blocks represent file system block size */ | |
4776 | return i_blocks << (inode->i_blkbits - 9); | |
4777 | } else { | |
4778 | return i_blocks; | |
4779 | } | |
0fc1b451 AK |
4780 | } else { |
4781 | return le32_to_cpu(raw_inode->i_blocks_lo); | |
4782 | } | |
4783 | } | |
ff9ddf7e | 4784 | |
1d1fe1ee | 4785 | struct inode *ext4_iget(struct super_block *sb, unsigned long ino) |
ac27a0ec | 4786 | { |
617ba13b MC |
4787 | struct ext4_iloc iloc; |
4788 | struct ext4_inode *raw_inode; | |
1d1fe1ee | 4789 | struct ext4_inode_info *ei; |
1d1fe1ee | 4790 | struct inode *inode; |
b436b9be | 4791 | journal_t *journal = EXT4_SB(sb)->s_journal; |
1d1fe1ee | 4792 | long ret; |
ac27a0ec DK |
4793 | int block; |
4794 | ||
1d1fe1ee DH |
4795 | inode = iget_locked(sb, ino); |
4796 | if (!inode) | |
4797 | return ERR_PTR(-ENOMEM); | |
4798 | if (!(inode->i_state & I_NEW)) | |
4799 | return inode; | |
4800 | ||
4801 | ei = EXT4_I(inode); | |
567f3e9a | 4802 | iloc.bh = 0; |
ac27a0ec | 4803 | |
1d1fe1ee DH |
4804 | ret = __ext4_get_inode_loc(inode, &iloc, 0); |
4805 | if (ret < 0) | |
ac27a0ec | 4806 | goto bad_inode; |
617ba13b | 4807 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec DK |
4808 | inode->i_mode = le16_to_cpu(raw_inode->i_mode); |
4809 | inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); | |
4810 | inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); | |
af5bc92d | 4811 | if (!(test_opt(inode->i_sb, NO_UID32))) { |
ac27a0ec DK |
4812 | inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; |
4813 | inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; | |
4814 | } | |
4815 | inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); | |
ac27a0ec DK |
4816 | |
4817 | ei->i_state = 0; | |
4818 | ei->i_dir_start_lookup = 0; | |
4819 | ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); | |
4820 | /* We now have enough fields to check if the inode was active or not. | |
4821 | * This is needed because nfsd might try to access dead inodes | |
4822 | * the test is that same one that e2fsck uses | |
4823 | * NeilBrown 1999oct15 | |
4824 | */ | |
4825 | if (inode->i_nlink == 0) { | |
4826 | if (inode->i_mode == 0 || | |
617ba13b | 4827 | !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) { |
ac27a0ec | 4828 | /* this inode is deleted */ |
1d1fe1ee | 4829 | ret = -ESTALE; |
ac27a0ec DK |
4830 | goto bad_inode; |
4831 | } | |
4832 | /* The only unlinked inodes we let through here have | |
4833 | * valid i_mode and are being read by the orphan | |
4834 | * recovery code: that's fine, we're about to complete | |
4835 | * the process of deleting those. */ | |
4836 | } | |
ac27a0ec | 4837 | ei->i_flags = le32_to_cpu(raw_inode->i_flags); |
0fc1b451 | 4838 | inode->i_blocks = ext4_inode_blocks(raw_inode, ei); |
7973c0c1 | 4839 | ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo); |
a9e81742 | 4840 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) |
a1ddeb7e BP |
4841 | ei->i_file_acl |= |
4842 | ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32; | |
a48380f7 | 4843 | inode->i_size = ext4_isize(raw_inode); |
ac27a0ec | 4844 | ei->i_disksize = inode->i_size; |
a9e7f447 DM |
4845 | #ifdef CONFIG_QUOTA |
4846 | ei->i_reserved_quota = 0; | |
4847 | #endif | |
ac27a0ec DK |
4848 | inode->i_generation = le32_to_cpu(raw_inode->i_generation); |
4849 | ei->i_block_group = iloc.block_group; | |
a4912123 | 4850 | ei->i_last_alloc_group = ~0; |
ac27a0ec DK |
4851 | /* |
4852 | * NOTE! The in-memory inode i_data array is in little-endian order | |
4853 | * even on big-endian machines: we do NOT byteswap the block numbers! | |
4854 | */ | |
617ba13b | 4855 | for (block = 0; block < EXT4_N_BLOCKS; block++) |
ac27a0ec DK |
4856 | ei->i_data[block] = raw_inode->i_block[block]; |
4857 | INIT_LIST_HEAD(&ei->i_orphan); | |
4858 | ||
b436b9be JK |
4859 | /* |
4860 | * Set transaction id's of transactions that have to be committed | |
4861 | * to finish f[data]sync. We set them to currently running transaction | |
4862 | * as we cannot be sure that the inode or some of its metadata isn't | |
4863 | * part of the transaction - the inode could have been reclaimed and | |
4864 | * now it is reread from disk. | |
4865 | */ | |
4866 | if (journal) { | |
4867 | transaction_t *transaction; | |
4868 | tid_t tid; | |
4869 | ||
4870 | spin_lock(&journal->j_state_lock); | |
4871 | if (journal->j_running_transaction) | |
4872 | transaction = journal->j_running_transaction; | |
4873 | else | |
4874 | transaction = journal->j_committing_transaction; | |
4875 | if (transaction) | |
4876 | tid = transaction->t_tid; | |
4877 | else | |
4878 | tid = journal->j_commit_sequence; | |
4879 | spin_unlock(&journal->j_state_lock); | |
4880 | ei->i_sync_tid = tid; | |
4881 | ei->i_datasync_tid = tid; | |
4882 | } | |
4883 | ||
0040d987 | 4884 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { |
ac27a0ec | 4885 | ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); |
617ba13b | 4886 | if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > |
e5d2861f | 4887 | EXT4_INODE_SIZE(inode->i_sb)) { |
1d1fe1ee | 4888 | ret = -EIO; |
ac27a0ec | 4889 | goto bad_inode; |
e5d2861f | 4890 | } |
ac27a0ec DK |
4891 | if (ei->i_extra_isize == 0) { |
4892 | /* The extra space is currently unused. Use it. */ | |
617ba13b MC |
4893 | ei->i_extra_isize = sizeof(struct ext4_inode) - |
4894 | EXT4_GOOD_OLD_INODE_SIZE; | |
ac27a0ec DK |
4895 | } else { |
4896 | __le32 *magic = (void *)raw_inode + | |
617ba13b | 4897 | EXT4_GOOD_OLD_INODE_SIZE + |
ac27a0ec | 4898 | ei->i_extra_isize; |
617ba13b | 4899 | if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC)) |
de9a55b8 | 4900 | ei->i_state |= EXT4_STATE_XATTR; |
ac27a0ec DK |
4901 | } |
4902 | } else | |
4903 | ei->i_extra_isize = 0; | |
4904 | ||
ef7f3835 KS |
4905 | EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode); |
4906 | EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode); | |
4907 | EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode); | |
4908 | EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode); | |
4909 | ||
25ec56b5 JNC |
4910 | inode->i_version = le32_to_cpu(raw_inode->i_disk_version); |
4911 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { | |
4912 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) | |
4913 | inode->i_version |= | |
4914 | (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32; | |
4915 | } | |
4916 | ||
c4b5a614 | 4917 | ret = 0; |
485c26ec | 4918 | if (ei->i_file_acl && |
1032988c | 4919 | !ext4_data_block_valid(EXT4_SB(sb), ei->i_file_acl, 1)) { |
485c26ec TT |
4920 | ext4_error(sb, __func__, |
4921 | "bad extended attribute block %llu in inode #%lu", | |
4922 | ei->i_file_acl, inode->i_ino); | |
4923 | ret = -EIO; | |
4924 | goto bad_inode; | |
4925 | } else if (ei->i_flags & EXT4_EXTENTS_FL) { | |
c4b5a614 TT |
4926 | if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
4927 | (S_ISLNK(inode->i_mode) && | |
4928 | !ext4_inode_is_fast_symlink(inode))) | |
4929 | /* Validate extent which is part of inode */ | |
4930 | ret = ext4_ext_check_inode(inode); | |
de9a55b8 | 4931 | } else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
fe2c8191 TN |
4932 | (S_ISLNK(inode->i_mode) && |
4933 | !ext4_inode_is_fast_symlink(inode))) { | |
de9a55b8 | 4934 | /* Validate block references which are part of inode */ |
fe2c8191 TN |
4935 | ret = ext4_check_inode_blockref(inode); |
4936 | } | |
567f3e9a | 4937 | if (ret) |
de9a55b8 | 4938 | goto bad_inode; |
7a262f7c | 4939 | |
ac27a0ec | 4940 | if (S_ISREG(inode->i_mode)) { |
617ba13b MC |
4941 | inode->i_op = &ext4_file_inode_operations; |
4942 | inode->i_fop = &ext4_file_operations; | |
4943 | ext4_set_aops(inode); | |
ac27a0ec | 4944 | } else if (S_ISDIR(inode->i_mode)) { |
617ba13b MC |
4945 | inode->i_op = &ext4_dir_inode_operations; |
4946 | inode->i_fop = &ext4_dir_operations; | |
ac27a0ec | 4947 | } else if (S_ISLNK(inode->i_mode)) { |
e83c1397 | 4948 | if (ext4_inode_is_fast_symlink(inode)) { |
617ba13b | 4949 | inode->i_op = &ext4_fast_symlink_inode_operations; |
e83c1397 DG |
4950 | nd_terminate_link(ei->i_data, inode->i_size, |
4951 | sizeof(ei->i_data) - 1); | |
4952 | } else { | |
617ba13b MC |
4953 | inode->i_op = &ext4_symlink_inode_operations; |
4954 | ext4_set_aops(inode); | |
ac27a0ec | 4955 | } |
563bdd61 TT |
4956 | } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || |
4957 | S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { | |
617ba13b | 4958 | inode->i_op = &ext4_special_inode_operations; |
ac27a0ec DK |
4959 | if (raw_inode->i_block[0]) |
4960 | init_special_inode(inode, inode->i_mode, | |
4961 | old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); | |
4962 | else | |
4963 | init_special_inode(inode, inode->i_mode, | |
4964 | new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); | |
563bdd61 | 4965 | } else { |
563bdd61 | 4966 | ret = -EIO; |
de9a55b8 | 4967 | ext4_error(inode->i_sb, __func__, |
563bdd61 TT |
4968 | "bogus i_mode (%o) for inode=%lu", |
4969 | inode->i_mode, inode->i_ino); | |
4970 | goto bad_inode; | |
ac27a0ec | 4971 | } |
af5bc92d | 4972 | brelse(iloc.bh); |
617ba13b | 4973 | ext4_set_inode_flags(inode); |
1d1fe1ee DH |
4974 | unlock_new_inode(inode); |
4975 | return inode; | |
ac27a0ec DK |
4976 | |
4977 | bad_inode: | |
567f3e9a | 4978 | brelse(iloc.bh); |
1d1fe1ee DH |
4979 | iget_failed(inode); |
4980 | return ERR_PTR(ret); | |
ac27a0ec DK |
4981 | } |
4982 | ||
0fc1b451 AK |
4983 | static int ext4_inode_blocks_set(handle_t *handle, |
4984 | struct ext4_inode *raw_inode, | |
4985 | struct ext4_inode_info *ei) | |
4986 | { | |
4987 | struct inode *inode = &(ei->vfs_inode); | |
4988 | u64 i_blocks = inode->i_blocks; | |
4989 | struct super_block *sb = inode->i_sb; | |
0fc1b451 AK |
4990 | |
4991 | if (i_blocks <= ~0U) { | |
4992 | /* | |
4993 | * i_blocks can be represnted in a 32 bit variable | |
4994 | * as multiple of 512 bytes | |
4995 | */ | |
8180a562 | 4996 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
0fc1b451 | 4997 | raw_inode->i_blocks_high = 0; |
8180a562 | 4998 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
f287a1a5 TT |
4999 | return 0; |
5000 | } | |
5001 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) | |
5002 | return -EFBIG; | |
5003 | ||
5004 | if (i_blocks <= 0xffffffffffffULL) { | |
0fc1b451 AK |
5005 | /* |
5006 | * i_blocks can be represented in a 48 bit variable | |
5007 | * as multiple of 512 bytes | |
5008 | */ | |
8180a562 | 5009 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
0fc1b451 | 5010 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); |
8180a562 | 5011 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
0fc1b451 | 5012 | } else { |
8180a562 AK |
5013 | ei->i_flags |= EXT4_HUGE_FILE_FL; |
5014 | /* i_block is stored in file system block size */ | |
5015 | i_blocks = i_blocks >> (inode->i_blkbits - 9); | |
5016 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); | |
5017 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); | |
0fc1b451 | 5018 | } |
f287a1a5 | 5019 | return 0; |
0fc1b451 AK |
5020 | } |
5021 | ||
ac27a0ec DK |
5022 | /* |
5023 | * Post the struct inode info into an on-disk inode location in the | |
5024 | * buffer-cache. This gobbles the caller's reference to the | |
5025 | * buffer_head in the inode location struct. | |
5026 | * | |
5027 | * The caller must have write access to iloc->bh. | |
5028 | */ | |
617ba13b | 5029 | static int ext4_do_update_inode(handle_t *handle, |
ac27a0ec | 5030 | struct inode *inode, |
830156c7 | 5031 | struct ext4_iloc *iloc) |
ac27a0ec | 5032 | { |
617ba13b MC |
5033 | struct ext4_inode *raw_inode = ext4_raw_inode(iloc); |
5034 | struct ext4_inode_info *ei = EXT4_I(inode); | |
ac27a0ec DK |
5035 | struct buffer_head *bh = iloc->bh; |
5036 | int err = 0, rc, block; | |
5037 | ||
5038 | /* For fields not not tracking in the in-memory inode, | |
5039 | * initialise them to zero for new inodes. */ | |
617ba13b MC |
5040 | if (ei->i_state & EXT4_STATE_NEW) |
5041 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); | |
ac27a0ec | 5042 | |
ff9ddf7e | 5043 | ext4_get_inode_flags(ei); |
ac27a0ec | 5044 | raw_inode->i_mode = cpu_to_le16(inode->i_mode); |
af5bc92d | 5045 | if (!(test_opt(inode->i_sb, NO_UID32))) { |
ac27a0ec DK |
5046 | raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid)); |
5047 | raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid)); | |
5048 | /* | |
5049 | * Fix up interoperability with old kernels. Otherwise, old inodes get | |
5050 | * re-used with the upper 16 bits of the uid/gid intact | |
5051 | */ | |
af5bc92d | 5052 | if (!ei->i_dtime) { |
ac27a0ec DK |
5053 | raw_inode->i_uid_high = |
5054 | cpu_to_le16(high_16_bits(inode->i_uid)); | |
5055 | raw_inode->i_gid_high = | |
5056 | cpu_to_le16(high_16_bits(inode->i_gid)); | |
5057 | } else { | |
5058 | raw_inode->i_uid_high = 0; | |
5059 | raw_inode->i_gid_high = 0; | |
5060 | } | |
5061 | } else { | |
5062 | raw_inode->i_uid_low = | |
5063 | cpu_to_le16(fs_high2lowuid(inode->i_uid)); | |
5064 | raw_inode->i_gid_low = | |
5065 | cpu_to_le16(fs_high2lowgid(inode->i_gid)); | |
5066 | raw_inode->i_uid_high = 0; | |
5067 | raw_inode->i_gid_high = 0; | |
5068 | } | |
5069 | raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); | |
ef7f3835 KS |
5070 | |
5071 | EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode); | |
5072 | EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode); | |
5073 | EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode); | |
5074 | EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode); | |
5075 | ||
0fc1b451 AK |
5076 | if (ext4_inode_blocks_set(handle, raw_inode, ei)) |
5077 | goto out_brelse; | |
ac27a0ec | 5078 | raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); |
1b9c12f4 | 5079 | raw_inode->i_flags = cpu_to_le32(ei->i_flags); |
9b8f1f01 MC |
5080 | if (EXT4_SB(inode->i_sb)->s_es->s_creator_os != |
5081 | cpu_to_le32(EXT4_OS_HURD)) | |
a1ddeb7e BP |
5082 | raw_inode->i_file_acl_high = |
5083 | cpu_to_le16(ei->i_file_acl >> 32); | |
7973c0c1 | 5084 | raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl); |
a48380f7 AK |
5085 | ext4_isize_set(raw_inode, ei->i_disksize); |
5086 | if (ei->i_disksize > 0x7fffffffULL) { | |
5087 | struct super_block *sb = inode->i_sb; | |
5088 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
5089 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE) || | |
5090 | EXT4_SB(sb)->s_es->s_rev_level == | |
5091 | cpu_to_le32(EXT4_GOOD_OLD_REV)) { | |
5092 | /* If this is the first large file | |
5093 | * created, add a flag to the superblock. | |
5094 | */ | |
5095 | err = ext4_journal_get_write_access(handle, | |
5096 | EXT4_SB(sb)->s_sbh); | |
5097 | if (err) | |
5098 | goto out_brelse; | |
5099 | ext4_update_dynamic_rev(sb); | |
5100 | EXT4_SET_RO_COMPAT_FEATURE(sb, | |
617ba13b | 5101 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE); |
a48380f7 | 5102 | sb->s_dirt = 1; |
0390131b FM |
5103 | ext4_handle_sync(handle); |
5104 | err = ext4_handle_dirty_metadata(handle, inode, | |
a48380f7 | 5105 | EXT4_SB(sb)->s_sbh); |
ac27a0ec DK |
5106 | } |
5107 | } | |
5108 | raw_inode->i_generation = cpu_to_le32(inode->i_generation); | |
5109 | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { | |
5110 | if (old_valid_dev(inode->i_rdev)) { | |
5111 | raw_inode->i_block[0] = | |
5112 | cpu_to_le32(old_encode_dev(inode->i_rdev)); | |
5113 | raw_inode->i_block[1] = 0; | |
5114 | } else { | |
5115 | raw_inode->i_block[0] = 0; | |
5116 | raw_inode->i_block[1] = | |
5117 | cpu_to_le32(new_encode_dev(inode->i_rdev)); | |
5118 | raw_inode->i_block[2] = 0; | |
5119 | } | |
de9a55b8 TT |
5120 | } else |
5121 | for (block = 0; block < EXT4_N_BLOCKS; block++) | |
5122 | raw_inode->i_block[block] = ei->i_data[block]; | |
ac27a0ec | 5123 | |
25ec56b5 JNC |
5124 | raw_inode->i_disk_version = cpu_to_le32(inode->i_version); |
5125 | if (ei->i_extra_isize) { | |
5126 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) | |
5127 | raw_inode->i_version_hi = | |
5128 | cpu_to_le32(inode->i_version >> 32); | |
ac27a0ec | 5129 | raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); |
25ec56b5 JNC |
5130 | } |
5131 | ||
830156c7 FM |
5132 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
5133 | rc = ext4_handle_dirty_metadata(handle, inode, bh); | |
5134 | if (!err) | |
5135 | err = rc; | |
617ba13b | 5136 | ei->i_state &= ~EXT4_STATE_NEW; |
ac27a0ec | 5137 | |
b436b9be | 5138 | ext4_update_inode_fsync_trans(handle, inode, 0); |
ac27a0ec | 5139 | out_brelse: |
af5bc92d | 5140 | brelse(bh); |
617ba13b | 5141 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5142 | return err; |
5143 | } | |
5144 | ||
5145 | /* | |
617ba13b | 5146 | * ext4_write_inode() |
ac27a0ec DK |
5147 | * |
5148 | * We are called from a few places: | |
5149 | * | |
5150 | * - Within generic_file_write() for O_SYNC files. | |
5151 | * Here, there will be no transaction running. We wait for any running | |
5152 | * trasnaction to commit. | |
5153 | * | |
5154 | * - Within sys_sync(), kupdate and such. | |
5155 | * We wait on commit, if tol to. | |
5156 | * | |
5157 | * - Within prune_icache() (PF_MEMALLOC == true) | |
5158 | * Here we simply return. We can't afford to block kswapd on the | |
5159 | * journal commit. | |
5160 | * | |
5161 | * In all cases it is actually safe for us to return without doing anything, | |
5162 | * because the inode has been copied into a raw inode buffer in | |
617ba13b | 5163 | * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for |
ac27a0ec DK |
5164 | * knfsd. |
5165 | * | |
5166 | * Note that we are absolutely dependent upon all inode dirtiers doing the | |
5167 | * right thing: they *must* call mark_inode_dirty() after dirtying info in | |
5168 | * which we are interested. | |
5169 | * | |
5170 | * It would be a bug for them to not do this. The code: | |
5171 | * | |
5172 | * mark_inode_dirty(inode) | |
5173 | * stuff(); | |
5174 | * inode->i_size = expr; | |
5175 | * | |
5176 | * is in error because a kswapd-driven write_inode() could occur while | |
5177 | * `stuff()' is running, and the new i_size will be lost. Plus the inode | |
5178 | * will no longer be on the superblock's dirty inode list. | |
5179 | */ | |
617ba13b | 5180 | int ext4_write_inode(struct inode *inode, int wait) |
ac27a0ec | 5181 | { |
91ac6f43 FM |
5182 | int err; |
5183 | ||
ac27a0ec DK |
5184 | if (current->flags & PF_MEMALLOC) |
5185 | return 0; | |
5186 | ||
91ac6f43 FM |
5187 | if (EXT4_SB(inode->i_sb)->s_journal) { |
5188 | if (ext4_journal_current_handle()) { | |
5189 | jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n"); | |
5190 | dump_stack(); | |
5191 | return -EIO; | |
5192 | } | |
ac27a0ec | 5193 | |
91ac6f43 FM |
5194 | if (!wait) |
5195 | return 0; | |
5196 | ||
5197 | err = ext4_force_commit(inode->i_sb); | |
5198 | } else { | |
5199 | struct ext4_iloc iloc; | |
ac27a0ec | 5200 | |
91ac6f43 FM |
5201 | err = ext4_get_inode_loc(inode, &iloc); |
5202 | if (err) | |
5203 | return err; | |
830156c7 FM |
5204 | if (wait) |
5205 | sync_dirty_buffer(iloc.bh); | |
5206 | if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) { | |
5207 | ext4_error(inode->i_sb, __func__, | |
5208 | "IO error syncing inode, " | |
5209 | "inode=%lu, block=%llu", | |
5210 | inode->i_ino, | |
5211 | (unsigned long long)iloc.bh->b_blocknr); | |
5212 | err = -EIO; | |
5213 | } | |
91ac6f43 FM |
5214 | } |
5215 | return err; | |
ac27a0ec DK |
5216 | } |
5217 | ||
5218 | /* | |
617ba13b | 5219 | * ext4_setattr() |
ac27a0ec DK |
5220 | * |
5221 | * Called from notify_change. | |
5222 | * | |
5223 | * We want to trap VFS attempts to truncate the file as soon as | |
5224 | * possible. In particular, we want to make sure that when the VFS | |
5225 | * shrinks i_size, we put the inode on the orphan list and modify | |
5226 | * i_disksize immediately, so that during the subsequent flushing of | |
5227 | * dirty pages and freeing of disk blocks, we can guarantee that any | |
5228 | * commit will leave the blocks being flushed in an unused state on | |
5229 | * disk. (On recovery, the inode will get truncated and the blocks will | |
5230 | * be freed, so we have a strong guarantee that no future commit will | |
5231 | * leave these blocks visible to the user.) | |
5232 | * | |
678aaf48 JK |
5233 | * Another thing we have to assure is that if we are in ordered mode |
5234 | * and inode is still attached to the committing transaction, we must | |
5235 | * we start writeout of all the dirty pages which are being truncated. | |
5236 | * This way we are sure that all the data written in the previous | |
5237 | * transaction are already on disk (truncate waits for pages under | |
5238 | * writeback). | |
5239 | * | |
5240 | * Called with inode->i_mutex down. | |
ac27a0ec | 5241 | */ |
617ba13b | 5242 | int ext4_setattr(struct dentry *dentry, struct iattr *attr) |
ac27a0ec DK |
5243 | { |
5244 | struct inode *inode = dentry->d_inode; | |
5245 | int error, rc = 0; | |
5246 | const unsigned int ia_valid = attr->ia_valid; | |
5247 | ||
5248 | error = inode_change_ok(inode, attr); | |
5249 | if (error) | |
5250 | return error; | |
5251 | ||
5252 | if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || | |
5253 | (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) { | |
5254 | handle_t *handle; | |
5255 | ||
5256 | /* (user+group)*(old+new) structure, inode write (sb, | |
5257 | * inode block, ? - but truncate inode update has it) */ | |
5aca07eb | 5258 | handle = ext4_journal_start(inode, (EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+ |
194074ac | 5259 | EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb))+3); |
ac27a0ec DK |
5260 | if (IS_ERR(handle)) { |
5261 | error = PTR_ERR(handle); | |
5262 | goto err_out; | |
5263 | } | |
a269eb18 | 5264 | error = vfs_dq_transfer(inode, attr) ? -EDQUOT : 0; |
ac27a0ec | 5265 | if (error) { |
617ba13b | 5266 | ext4_journal_stop(handle); |
ac27a0ec DK |
5267 | return error; |
5268 | } | |
5269 | /* Update corresponding info in inode so that everything is in | |
5270 | * one transaction */ | |
5271 | if (attr->ia_valid & ATTR_UID) | |
5272 | inode->i_uid = attr->ia_uid; | |
5273 | if (attr->ia_valid & ATTR_GID) | |
5274 | inode->i_gid = attr->ia_gid; | |
617ba13b MC |
5275 | error = ext4_mark_inode_dirty(handle, inode); |
5276 | ext4_journal_stop(handle); | |
ac27a0ec DK |
5277 | } |
5278 | ||
e2b46574 ES |
5279 | if (attr->ia_valid & ATTR_SIZE) { |
5280 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) { | |
5281 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
5282 | ||
5283 | if (attr->ia_size > sbi->s_bitmap_maxbytes) { | |
5284 | error = -EFBIG; | |
5285 | goto err_out; | |
5286 | } | |
5287 | } | |
5288 | } | |
5289 | ||
ac27a0ec DK |
5290 | if (S_ISREG(inode->i_mode) && |
5291 | attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { | |
5292 | handle_t *handle; | |
5293 | ||
617ba13b | 5294 | handle = ext4_journal_start(inode, 3); |
ac27a0ec DK |
5295 | if (IS_ERR(handle)) { |
5296 | error = PTR_ERR(handle); | |
5297 | goto err_out; | |
5298 | } | |
5299 | ||
617ba13b MC |
5300 | error = ext4_orphan_add(handle, inode); |
5301 | EXT4_I(inode)->i_disksize = attr->ia_size; | |
5302 | rc = ext4_mark_inode_dirty(handle, inode); | |
ac27a0ec DK |
5303 | if (!error) |
5304 | error = rc; | |
617ba13b | 5305 | ext4_journal_stop(handle); |
678aaf48 JK |
5306 | |
5307 | if (ext4_should_order_data(inode)) { | |
5308 | error = ext4_begin_ordered_truncate(inode, | |
5309 | attr->ia_size); | |
5310 | if (error) { | |
5311 | /* Do as much error cleanup as possible */ | |
5312 | handle = ext4_journal_start(inode, 3); | |
5313 | if (IS_ERR(handle)) { | |
5314 | ext4_orphan_del(NULL, inode); | |
5315 | goto err_out; | |
5316 | } | |
5317 | ext4_orphan_del(handle, inode); | |
5318 | ext4_journal_stop(handle); | |
5319 | goto err_out; | |
5320 | } | |
5321 | } | |
ac27a0ec DK |
5322 | } |
5323 | ||
5324 | rc = inode_setattr(inode, attr); | |
5325 | ||
617ba13b | 5326 | /* If inode_setattr's call to ext4_truncate failed to get a |
ac27a0ec DK |
5327 | * transaction handle at all, we need to clean up the in-core |
5328 | * orphan list manually. */ | |
5329 | if (inode->i_nlink) | |
617ba13b | 5330 | ext4_orphan_del(NULL, inode); |
ac27a0ec DK |
5331 | |
5332 | if (!rc && (ia_valid & ATTR_MODE)) | |
617ba13b | 5333 | rc = ext4_acl_chmod(inode); |
ac27a0ec DK |
5334 | |
5335 | err_out: | |
617ba13b | 5336 | ext4_std_error(inode->i_sb, error); |
ac27a0ec DK |
5337 | if (!error) |
5338 | error = rc; | |
5339 | return error; | |
5340 | } | |
5341 | ||
3e3398a0 MC |
5342 | int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, |
5343 | struct kstat *stat) | |
5344 | { | |
5345 | struct inode *inode; | |
5346 | unsigned long delalloc_blocks; | |
5347 | ||
5348 | inode = dentry->d_inode; | |
5349 | generic_fillattr(inode, stat); | |
5350 | ||
5351 | /* | |
5352 | * We can't update i_blocks if the block allocation is delayed | |
5353 | * otherwise in the case of system crash before the real block | |
5354 | * allocation is done, we will have i_blocks inconsistent with | |
5355 | * on-disk file blocks. | |
5356 | * We always keep i_blocks updated together with real | |
5357 | * allocation. But to not confuse with user, stat | |
5358 | * will return the blocks that include the delayed allocation | |
5359 | * blocks for this file. | |
5360 | */ | |
5361 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
5362 | delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks; | |
5363 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
5364 | ||
5365 | stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9; | |
5366 | return 0; | |
5367 | } | |
ac27a0ec | 5368 | |
a02908f1 MC |
5369 | static int ext4_indirect_trans_blocks(struct inode *inode, int nrblocks, |
5370 | int chunk) | |
5371 | { | |
5372 | int indirects; | |
5373 | ||
5374 | /* if nrblocks are contiguous */ | |
5375 | if (chunk) { | |
5376 | /* | |
5377 | * With N contiguous data blocks, it need at most | |
5378 | * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) indirect blocks | |
5379 | * 2 dindirect blocks | |
5380 | * 1 tindirect block | |
5381 | */ | |
5382 | indirects = nrblocks / EXT4_ADDR_PER_BLOCK(inode->i_sb); | |
5383 | return indirects + 3; | |
5384 | } | |
5385 | /* | |
5386 | * if nrblocks are not contiguous, worse case, each block touch | |
5387 | * a indirect block, and each indirect block touch a double indirect | |
5388 | * block, plus a triple indirect block | |
5389 | */ | |
5390 | indirects = nrblocks * 2 + 1; | |
5391 | return indirects; | |
5392 | } | |
5393 | ||
5394 | static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
5395 | { | |
5396 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) | |
ac51d837 TT |
5397 | return ext4_indirect_trans_blocks(inode, nrblocks, chunk); |
5398 | return ext4_ext_index_trans_blocks(inode, nrblocks, chunk); | |
a02908f1 | 5399 | } |
ac51d837 | 5400 | |
ac27a0ec | 5401 | /* |
a02908f1 MC |
5402 | * Account for index blocks, block groups bitmaps and block group |
5403 | * descriptor blocks if modify datablocks and index blocks | |
5404 | * worse case, the indexs blocks spread over different block groups | |
ac27a0ec | 5405 | * |
a02908f1 | 5406 | * If datablocks are discontiguous, they are possible to spread over |
af901ca1 | 5407 | * different block groups too. If they are contiuguous, with flexbg, |
a02908f1 | 5408 | * they could still across block group boundary. |
ac27a0ec | 5409 | * |
a02908f1 MC |
5410 | * Also account for superblock, inode, quota and xattr blocks |
5411 | */ | |
5412 | int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
5413 | { | |
8df9675f TT |
5414 | ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb); |
5415 | int gdpblocks; | |
a02908f1 MC |
5416 | int idxblocks; |
5417 | int ret = 0; | |
5418 | ||
5419 | /* | |
5420 | * How many index blocks need to touch to modify nrblocks? | |
5421 | * The "Chunk" flag indicating whether the nrblocks is | |
5422 | * physically contiguous on disk | |
5423 | * | |
5424 | * For Direct IO and fallocate, they calls get_block to allocate | |
5425 | * one single extent at a time, so they could set the "Chunk" flag | |
5426 | */ | |
5427 | idxblocks = ext4_index_trans_blocks(inode, nrblocks, chunk); | |
5428 | ||
5429 | ret = idxblocks; | |
5430 | ||
5431 | /* | |
5432 | * Now let's see how many group bitmaps and group descriptors need | |
5433 | * to account | |
5434 | */ | |
5435 | groups = idxblocks; | |
5436 | if (chunk) | |
5437 | groups += 1; | |
5438 | else | |
5439 | groups += nrblocks; | |
5440 | ||
5441 | gdpblocks = groups; | |
8df9675f TT |
5442 | if (groups > ngroups) |
5443 | groups = ngroups; | |
a02908f1 MC |
5444 | if (groups > EXT4_SB(inode->i_sb)->s_gdb_count) |
5445 | gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count; | |
5446 | ||
5447 | /* bitmaps and block group descriptor blocks */ | |
5448 | ret += groups + gdpblocks; | |
5449 | ||
5450 | /* Blocks for super block, inode, quota and xattr blocks */ | |
5451 | ret += EXT4_META_TRANS_BLOCKS(inode->i_sb); | |
5452 | ||
5453 | return ret; | |
5454 | } | |
5455 | ||
5456 | /* | |
5457 | * Calulate the total number of credits to reserve to fit | |
f3bd1f3f MC |
5458 | * the modification of a single pages into a single transaction, |
5459 | * which may include multiple chunks of block allocations. | |
ac27a0ec | 5460 | * |
525f4ed8 | 5461 | * This could be called via ext4_write_begin() |
ac27a0ec | 5462 | * |
525f4ed8 | 5463 | * We need to consider the worse case, when |
a02908f1 | 5464 | * one new block per extent. |
ac27a0ec | 5465 | */ |
a86c6181 | 5466 | int ext4_writepage_trans_blocks(struct inode *inode) |
ac27a0ec | 5467 | { |
617ba13b | 5468 | int bpp = ext4_journal_blocks_per_page(inode); |
ac27a0ec DK |
5469 | int ret; |
5470 | ||
a02908f1 | 5471 | ret = ext4_meta_trans_blocks(inode, bpp, 0); |
a86c6181 | 5472 | |
a02908f1 | 5473 | /* Account for data blocks for journalled mode */ |
617ba13b | 5474 | if (ext4_should_journal_data(inode)) |
a02908f1 | 5475 | ret += bpp; |
ac27a0ec DK |
5476 | return ret; |
5477 | } | |
f3bd1f3f MC |
5478 | |
5479 | /* | |
5480 | * Calculate the journal credits for a chunk of data modification. | |
5481 | * | |
5482 | * This is called from DIO, fallocate or whoever calling | |
af901ca1 | 5483 | * ext4_get_blocks() to map/allocate a chunk of contiguous disk blocks. |
f3bd1f3f MC |
5484 | * |
5485 | * journal buffers for data blocks are not included here, as DIO | |
5486 | * and fallocate do no need to journal data buffers. | |
5487 | */ | |
5488 | int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks) | |
5489 | { | |
5490 | return ext4_meta_trans_blocks(inode, nrblocks, 1); | |
5491 | } | |
5492 | ||
ac27a0ec | 5493 | /* |
617ba13b | 5494 | * The caller must have previously called ext4_reserve_inode_write(). |
ac27a0ec DK |
5495 | * Give this, we know that the caller already has write access to iloc->bh. |
5496 | */ | |
617ba13b | 5497 | int ext4_mark_iloc_dirty(handle_t *handle, |
de9a55b8 | 5498 | struct inode *inode, struct ext4_iloc *iloc) |
ac27a0ec DK |
5499 | { |
5500 | int err = 0; | |
5501 | ||
25ec56b5 JNC |
5502 | if (test_opt(inode->i_sb, I_VERSION)) |
5503 | inode_inc_iversion(inode); | |
5504 | ||
ac27a0ec DK |
5505 | /* the do_update_inode consumes one bh->b_count */ |
5506 | get_bh(iloc->bh); | |
5507 | ||
dab291af | 5508 | /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */ |
830156c7 | 5509 | err = ext4_do_update_inode(handle, inode, iloc); |
ac27a0ec DK |
5510 | put_bh(iloc->bh); |
5511 | return err; | |
5512 | } | |
5513 | ||
5514 | /* | |
5515 | * On success, We end up with an outstanding reference count against | |
5516 | * iloc->bh. This _must_ be cleaned up later. | |
5517 | */ | |
5518 | ||
5519 | int | |
617ba13b MC |
5520 | ext4_reserve_inode_write(handle_t *handle, struct inode *inode, |
5521 | struct ext4_iloc *iloc) | |
ac27a0ec | 5522 | { |
0390131b FM |
5523 | int err; |
5524 | ||
5525 | err = ext4_get_inode_loc(inode, iloc); | |
5526 | if (!err) { | |
5527 | BUFFER_TRACE(iloc->bh, "get_write_access"); | |
5528 | err = ext4_journal_get_write_access(handle, iloc->bh); | |
5529 | if (err) { | |
5530 | brelse(iloc->bh); | |
5531 | iloc->bh = NULL; | |
ac27a0ec DK |
5532 | } |
5533 | } | |
617ba13b | 5534 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5535 | return err; |
5536 | } | |
5537 | ||
6dd4ee7c KS |
5538 | /* |
5539 | * Expand an inode by new_extra_isize bytes. | |
5540 | * Returns 0 on success or negative error number on failure. | |
5541 | */ | |
1d03ec98 AK |
5542 | static int ext4_expand_extra_isize(struct inode *inode, |
5543 | unsigned int new_extra_isize, | |
5544 | struct ext4_iloc iloc, | |
5545 | handle_t *handle) | |
6dd4ee7c KS |
5546 | { |
5547 | struct ext4_inode *raw_inode; | |
5548 | struct ext4_xattr_ibody_header *header; | |
5549 | struct ext4_xattr_entry *entry; | |
5550 | ||
5551 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) | |
5552 | return 0; | |
5553 | ||
5554 | raw_inode = ext4_raw_inode(&iloc); | |
5555 | ||
5556 | header = IHDR(inode, raw_inode); | |
5557 | entry = IFIRST(header); | |
5558 | ||
5559 | /* No extended attributes present */ | |
5560 | if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR) || | |
5561 | header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { | |
5562 | memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0, | |
5563 | new_extra_isize); | |
5564 | EXT4_I(inode)->i_extra_isize = new_extra_isize; | |
5565 | return 0; | |
5566 | } | |
5567 | ||
5568 | /* try to expand with EAs present */ | |
5569 | return ext4_expand_extra_isize_ea(inode, new_extra_isize, | |
5570 | raw_inode, handle); | |
5571 | } | |
5572 | ||
ac27a0ec DK |
5573 | /* |
5574 | * What we do here is to mark the in-core inode as clean with respect to inode | |
5575 | * dirtiness (it may still be data-dirty). | |
5576 | * This means that the in-core inode may be reaped by prune_icache | |
5577 | * without having to perform any I/O. This is a very good thing, | |
5578 | * because *any* task may call prune_icache - even ones which | |
5579 | * have a transaction open against a different journal. | |
5580 | * | |
5581 | * Is this cheating? Not really. Sure, we haven't written the | |
5582 | * inode out, but prune_icache isn't a user-visible syncing function. | |
5583 | * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) | |
5584 | * we start and wait on commits. | |
5585 | * | |
5586 | * Is this efficient/effective? Well, we're being nice to the system | |
5587 | * by cleaning up our inodes proactively so they can be reaped | |
5588 | * without I/O. But we are potentially leaving up to five seconds' | |
5589 | * worth of inodes floating about which prune_icache wants us to | |
5590 | * write out. One way to fix that would be to get prune_icache() | |
5591 | * to do a write_super() to free up some memory. It has the desired | |
5592 | * effect. | |
5593 | */ | |
617ba13b | 5594 | int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode) |
ac27a0ec | 5595 | { |
617ba13b | 5596 | struct ext4_iloc iloc; |
6dd4ee7c KS |
5597 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
5598 | static unsigned int mnt_count; | |
5599 | int err, ret; | |
ac27a0ec DK |
5600 | |
5601 | might_sleep(); | |
617ba13b | 5602 | err = ext4_reserve_inode_write(handle, inode, &iloc); |
0390131b FM |
5603 | if (ext4_handle_valid(handle) && |
5604 | EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize && | |
6dd4ee7c KS |
5605 | !(EXT4_I(inode)->i_state & EXT4_STATE_NO_EXPAND)) { |
5606 | /* | |
5607 | * We need extra buffer credits since we may write into EA block | |
5608 | * with this same handle. If journal_extend fails, then it will | |
5609 | * only result in a minor loss of functionality for that inode. | |
5610 | * If this is felt to be critical, then e2fsck should be run to | |
5611 | * force a large enough s_min_extra_isize. | |
5612 | */ | |
5613 | if ((jbd2_journal_extend(handle, | |
5614 | EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) { | |
5615 | ret = ext4_expand_extra_isize(inode, | |
5616 | sbi->s_want_extra_isize, | |
5617 | iloc, handle); | |
5618 | if (ret) { | |
5619 | EXT4_I(inode)->i_state |= EXT4_STATE_NO_EXPAND; | |
c1bddad9 AK |
5620 | if (mnt_count != |
5621 | le16_to_cpu(sbi->s_es->s_mnt_count)) { | |
46e665e9 | 5622 | ext4_warning(inode->i_sb, __func__, |
6dd4ee7c KS |
5623 | "Unable to expand inode %lu. Delete" |
5624 | " some EAs or run e2fsck.", | |
5625 | inode->i_ino); | |
c1bddad9 AK |
5626 | mnt_count = |
5627 | le16_to_cpu(sbi->s_es->s_mnt_count); | |
6dd4ee7c KS |
5628 | } |
5629 | } | |
5630 | } | |
5631 | } | |
ac27a0ec | 5632 | if (!err) |
617ba13b | 5633 | err = ext4_mark_iloc_dirty(handle, inode, &iloc); |
ac27a0ec DK |
5634 | return err; |
5635 | } | |
5636 | ||
5637 | /* | |
617ba13b | 5638 | * ext4_dirty_inode() is called from __mark_inode_dirty() |
ac27a0ec DK |
5639 | * |
5640 | * We're really interested in the case where a file is being extended. | |
5641 | * i_size has been changed by generic_commit_write() and we thus need | |
5642 | * to include the updated inode in the current transaction. | |
5643 | * | |
a269eb18 | 5644 | * Also, vfs_dq_alloc_block() will always dirty the inode when blocks |
ac27a0ec DK |
5645 | * are allocated to the file. |
5646 | * | |
5647 | * If the inode is marked synchronous, we don't honour that here - doing | |
5648 | * so would cause a commit on atime updates, which we don't bother doing. | |
5649 | * We handle synchronous inodes at the highest possible level. | |
5650 | */ | |
617ba13b | 5651 | void ext4_dirty_inode(struct inode *inode) |
ac27a0ec | 5652 | { |
ac27a0ec DK |
5653 | handle_t *handle; |
5654 | ||
617ba13b | 5655 | handle = ext4_journal_start(inode, 2); |
ac27a0ec DK |
5656 | if (IS_ERR(handle)) |
5657 | goto out; | |
f3dc272f | 5658 | |
f3dc272f CW |
5659 | ext4_mark_inode_dirty(handle, inode); |
5660 | ||
617ba13b | 5661 | ext4_journal_stop(handle); |
ac27a0ec DK |
5662 | out: |
5663 | return; | |
5664 | } | |
5665 | ||
5666 | #if 0 | |
5667 | /* | |
5668 | * Bind an inode's backing buffer_head into this transaction, to prevent | |
5669 | * it from being flushed to disk early. Unlike | |
617ba13b | 5670 | * ext4_reserve_inode_write, this leaves behind no bh reference and |
ac27a0ec DK |
5671 | * returns no iloc structure, so the caller needs to repeat the iloc |
5672 | * lookup to mark the inode dirty later. | |
5673 | */ | |
617ba13b | 5674 | static int ext4_pin_inode(handle_t *handle, struct inode *inode) |
ac27a0ec | 5675 | { |
617ba13b | 5676 | struct ext4_iloc iloc; |
ac27a0ec DK |
5677 | |
5678 | int err = 0; | |
5679 | if (handle) { | |
617ba13b | 5680 | err = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
5681 | if (!err) { |
5682 | BUFFER_TRACE(iloc.bh, "get_write_access"); | |
dab291af | 5683 | err = jbd2_journal_get_write_access(handle, iloc.bh); |
ac27a0ec | 5684 | if (!err) |
0390131b FM |
5685 | err = ext4_handle_dirty_metadata(handle, |
5686 | inode, | |
5687 | iloc.bh); | |
ac27a0ec DK |
5688 | brelse(iloc.bh); |
5689 | } | |
5690 | } | |
617ba13b | 5691 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5692 | return err; |
5693 | } | |
5694 | #endif | |
5695 | ||
617ba13b | 5696 | int ext4_change_inode_journal_flag(struct inode *inode, int val) |
ac27a0ec DK |
5697 | { |
5698 | journal_t *journal; | |
5699 | handle_t *handle; | |
5700 | int err; | |
5701 | ||
5702 | /* | |
5703 | * We have to be very careful here: changing a data block's | |
5704 | * journaling status dynamically is dangerous. If we write a | |
5705 | * data block to the journal, change the status and then delete | |
5706 | * that block, we risk forgetting to revoke the old log record | |
5707 | * from the journal and so a subsequent replay can corrupt data. | |
5708 | * So, first we make sure that the journal is empty and that | |
5709 | * nobody is changing anything. | |
5710 | */ | |
5711 | ||
617ba13b | 5712 | journal = EXT4_JOURNAL(inode); |
0390131b FM |
5713 | if (!journal) |
5714 | return 0; | |
d699594d | 5715 | if (is_journal_aborted(journal)) |
ac27a0ec DK |
5716 | return -EROFS; |
5717 | ||
dab291af MC |
5718 | jbd2_journal_lock_updates(journal); |
5719 | jbd2_journal_flush(journal); | |
ac27a0ec DK |
5720 | |
5721 | /* | |
5722 | * OK, there are no updates running now, and all cached data is | |
5723 | * synced to disk. We are now in a completely consistent state | |
5724 | * which doesn't have anything in the journal, and we know that | |
5725 | * no filesystem updates are running, so it is safe to modify | |
5726 | * the inode's in-core data-journaling state flag now. | |
5727 | */ | |
5728 | ||
5729 | if (val) | |
617ba13b | 5730 | EXT4_I(inode)->i_flags |= EXT4_JOURNAL_DATA_FL; |
ac27a0ec | 5731 | else |
617ba13b MC |
5732 | EXT4_I(inode)->i_flags &= ~EXT4_JOURNAL_DATA_FL; |
5733 | ext4_set_aops(inode); | |
ac27a0ec | 5734 | |
dab291af | 5735 | jbd2_journal_unlock_updates(journal); |
ac27a0ec DK |
5736 | |
5737 | /* Finally we can mark the inode as dirty. */ | |
5738 | ||
617ba13b | 5739 | handle = ext4_journal_start(inode, 1); |
ac27a0ec DK |
5740 | if (IS_ERR(handle)) |
5741 | return PTR_ERR(handle); | |
5742 | ||
617ba13b | 5743 | err = ext4_mark_inode_dirty(handle, inode); |
0390131b | 5744 | ext4_handle_sync(handle); |
617ba13b MC |
5745 | ext4_journal_stop(handle); |
5746 | ext4_std_error(inode->i_sb, err); | |
ac27a0ec DK |
5747 | |
5748 | return err; | |
5749 | } | |
2e9ee850 AK |
5750 | |
5751 | static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh) | |
5752 | { | |
5753 | return !buffer_mapped(bh); | |
5754 | } | |
5755 | ||
c2ec175c | 5756 | int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
2e9ee850 | 5757 | { |
c2ec175c | 5758 | struct page *page = vmf->page; |
2e9ee850 AK |
5759 | loff_t size; |
5760 | unsigned long len; | |
5761 | int ret = -EINVAL; | |
79f0be8d | 5762 | void *fsdata; |
2e9ee850 AK |
5763 | struct file *file = vma->vm_file; |
5764 | struct inode *inode = file->f_path.dentry->d_inode; | |
5765 | struct address_space *mapping = inode->i_mapping; | |
5766 | ||
5767 | /* | |
5768 | * Get i_alloc_sem to stop truncates messing with the inode. We cannot | |
5769 | * get i_mutex because we are already holding mmap_sem. | |
5770 | */ | |
5771 | down_read(&inode->i_alloc_sem); | |
5772 | size = i_size_read(inode); | |
5773 | if (page->mapping != mapping || size <= page_offset(page) | |
5774 | || !PageUptodate(page)) { | |
5775 | /* page got truncated from under us? */ | |
5776 | goto out_unlock; | |
5777 | } | |
5778 | ret = 0; | |
5779 | if (PageMappedToDisk(page)) | |
5780 | goto out_unlock; | |
5781 | ||
5782 | if (page->index == size >> PAGE_CACHE_SHIFT) | |
5783 | len = size & ~PAGE_CACHE_MASK; | |
5784 | else | |
5785 | len = PAGE_CACHE_SIZE; | |
5786 | ||
a827eaff AK |
5787 | lock_page(page); |
5788 | /* | |
5789 | * return if we have all the buffers mapped. This avoid | |
5790 | * the need to call write_begin/write_end which does a | |
5791 | * journal_start/journal_stop which can block and take | |
5792 | * long time | |
5793 | */ | |
2e9ee850 | 5794 | if (page_has_buffers(page)) { |
2e9ee850 | 5795 | if (!walk_page_buffers(NULL, page_buffers(page), 0, len, NULL, |
a827eaff AK |
5796 | ext4_bh_unmapped)) { |
5797 | unlock_page(page); | |
2e9ee850 | 5798 | goto out_unlock; |
a827eaff | 5799 | } |
2e9ee850 | 5800 | } |
a827eaff | 5801 | unlock_page(page); |
2e9ee850 AK |
5802 | /* |
5803 | * OK, we need to fill the hole... Do write_begin write_end | |
5804 | * to do block allocation/reservation.We are not holding | |
5805 | * inode.i__mutex here. That allow * parallel write_begin, | |
5806 | * write_end call. lock_page prevent this from happening | |
5807 | * on the same page though | |
5808 | */ | |
5809 | ret = mapping->a_ops->write_begin(file, mapping, page_offset(page), | |
79f0be8d | 5810 | len, AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata); |
2e9ee850 AK |
5811 | if (ret < 0) |
5812 | goto out_unlock; | |
5813 | ret = mapping->a_ops->write_end(file, mapping, page_offset(page), | |
79f0be8d | 5814 | len, len, page, fsdata); |
2e9ee850 AK |
5815 | if (ret < 0) |
5816 | goto out_unlock; | |
5817 | ret = 0; | |
5818 | out_unlock: | |
c2ec175c NP |
5819 | if (ret) |
5820 | ret = VM_FAULT_SIGBUS; | |
2e9ee850 AK |
5821 | up_read(&inode->i_alloc_sem); |
5822 | return ret; | |
5823 | } |