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> | |
9bffad1e | 40 | |
3dcf5451 | 41 | #include "ext4_jbd2.h" |
ac27a0ec DK |
42 | #include "xattr.h" |
43 | #include "acl.h" | |
d2a17637 | 44 | #include "ext4_extents.h" |
ac27a0ec | 45 | |
9bffad1e TT |
46 | #include <trace/events/ext4.h> |
47 | ||
a1d6cc56 AK |
48 | #define MPAGE_DA_EXTENT_TAIL 0x01 |
49 | ||
678aaf48 JK |
50 | static inline int ext4_begin_ordered_truncate(struct inode *inode, |
51 | loff_t new_size) | |
52 | { | |
7f5aa215 JK |
53 | return jbd2_journal_begin_ordered_truncate( |
54 | EXT4_SB(inode->i_sb)->s_journal, | |
55 | &EXT4_I(inode)->jinode, | |
56 | new_size); | |
678aaf48 JK |
57 | } |
58 | ||
64769240 AT |
59 | static void ext4_invalidatepage(struct page *page, unsigned long offset); |
60 | ||
ac27a0ec DK |
61 | /* |
62 | * Test whether an inode is a fast symlink. | |
63 | */ | |
617ba13b | 64 | static int ext4_inode_is_fast_symlink(struct inode *inode) |
ac27a0ec | 65 | { |
617ba13b | 66 | int ea_blocks = EXT4_I(inode)->i_file_acl ? |
ac27a0ec DK |
67 | (inode->i_sb->s_blocksize >> 9) : 0; |
68 | ||
69 | return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); | |
70 | } | |
71 | ||
72 | /* | |
617ba13b | 73 | * The ext4 forget function must perform a revoke if we are freeing data |
ac27a0ec DK |
74 | * which has been journaled. Metadata (eg. indirect blocks) must be |
75 | * revoked in all cases. | |
76 | * | |
77 | * "bh" may be NULL: a metadata block may have been freed from memory | |
78 | * but there may still be a record of it in the journal, and that record | |
79 | * still needs to be revoked. | |
0390131b | 80 | * |
e6b5d301 CW |
81 | * If the handle isn't valid we're not journaling, but we still need to |
82 | * call into ext4_journal_revoke() to put the buffer head. | |
ac27a0ec | 83 | */ |
617ba13b | 84 | int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode, |
de9a55b8 | 85 | struct buffer_head *bh, ext4_fsblk_t blocknr) |
ac27a0ec DK |
86 | { |
87 | int err; | |
88 | ||
89 | might_sleep(); | |
90 | ||
91 | BUFFER_TRACE(bh, "enter"); | |
92 | ||
93 | jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " | |
7f4520cc | 94 | "data mode %x\n", |
ac27a0ec DK |
95 | bh, is_metadata, inode->i_mode, |
96 | test_opt(inode->i_sb, DATA_FLAGS)); | |
97 | ||
98 | /* Never use the revoke function if we are doing full data | |
99 | * journaling: there is no need to, and a V1 superblock won't | |
100 | * support it. Otherwise, only skip the revoke on un-journaled | |
101 | * data blocks. */ | |
102 | ||
617ba13b MC |
103 | if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || |
104 | (!is_metadata && !ext4_should_journal_data(inode))) { | |
ac27a0ec | 105 | if (bh) { |
dab291af | 106 | BUFFER_TRACE(bh, "call jbd2_journal_forget"); |
617ba13b | 107 | return ext4_journal_forget(handle, bh); |
ac27a0ec DK |
108 | } |
109 | return 0; | |
110 | } | |
111 | ||
112 | /* | |
113 | * data!=journal && (is_metadata || should_journal_data(inode)) | |
114 | */ | |
617ba13b MC |
115 | BUFFER_TRACE(bh, "call ext4_journal_revoke"); |
116 | err = ext4_journal_revoke(handle, blocknr, bh); | |
ac27a0ec | 117 | if (err) |
46e665e9 | 118 | ext4_abort(inode->i_sb, __func__, |
ac27a0ec DK |
119 | "error %d when attempting revoke", err); |
120 | BUFFER_TRACE(bh, "exit"); | |
121 | return err; | |
122 | } | |
123 | ||
124 | /* | |
125 | * Work out how many blocks we need to proceed with the next chunk of a | |
126 | * truncate transaction. | |
127 | */ | |
128 | static unsigned long blocks_for_truncate(struct inode *inode) | |
129 | { | |
725d26d3 | 130 | ext4_lblk_t needed; |
ac27a0ec DK |
131 | |
132 | needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); | |
133 | ||
134 | /* Give ourselves just enough room to cope with inodes in which | |
135 | * i_blocks is corrupt: we've seen disk corruptions in the past | |
136 | * which resulted in random data in an inode which looked enough | |
617ba13b | 137 | * like a regular file for ext4 to try to delete it. Things |
ac27a0ec DK |
138 | * will go a bit crazy if that happens, but at least we should |
139 | * try not to panic the whole kernel. */ | |
140 | if (needed < 2) | |
141 | needed = 2; | |
142 | ||
143 | /* But we need to bound the transaction so we don't overflow the | |
144 | * journal. */ | |
617ba13b MC |
145 | if (needed > EXT4_MAX_TRANS_DATA) |
146 | needed = EXT4_MAX_TRANS_DATA; | |
ac27a0ec | 147 | |
617ba13b | 148 | return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed; |
ac27a0ec DK |
149 | } |
150 | ||
151 | /* | |
152 | * Truncate transactions can be complex and absolutely huge. So we need to | |
153 | * be able to restart the transaction at a conventient checkpoint to make | |
154 | * sure we don't overflow the journal. | |
155 | * | |
156 | * start_transaction gets us a new handle for a truncate transaction, | |
157 | * and extend_transaction tries to extend the existing one a bit. If | |
158 | * extend fails, we need to propagate the failure up and restart the | |
159 | * transaction in the top-level truncate loop. --sct | |
160 | */ | |
161 | static handle_t *start_transaction(struct inode *inode) | |
162 | { | |
163 | handle_t *result; | |
164 | ||
617ba13b | 165 | result = ext4_journal_start(inode, blocks_for_truncate(inode)); |
ac27a0ec DK |
166 | if (!IS_ERR(result)) |
167 | return result; | |
168 | ||
617ba13b | 169 | ext4_std_error(inode->i_sb, PTR_ERR(result)); |
ac27a0ec DK |
170 | return result; |
171 | } | |
172 | ||
173 | /* | |
174 | * Try to extend this transaction for the purposes of truncation. | |
175 | * | |
176 | * Returns 0 if we managed to create more room. If we can't create more | |
177 | * room, and the transaction must be restarted we return 1. | |
178 | */ | |
179 | static int try_to_extend_transaction(handle_t *handle, struct inode *inode) | |
180 | { | |
0390131b FM |
181 | if (!ext4_handle_valid(handle)) |
182 | return 0; | |
183 | if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1)) | |
ac27a0ec | 184 | return 0; |
617ba13b | 185 | if (!ext4_journal_extend(handle, blocks_for_truncate(inode))) |
ac27a0ec DK |
186 | return 0; |
187 | return 1; | |
188 | } | |
189 | ||
190 | /* | |
191 | * Restart the transaction associated with *handle. This does a commit, | |
192 | * so before we call here everything must be consistently dirtied against | |
193 | * this transaction. | |
194 | */ | |
487caeef JK |
195 | int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode, |
196 | int nblocks) | |
ac27a0ec | 197 | { |
487caeef JK |
198 | int ret; |
199 | ||
200 | /* | |
201 | * Drop i_data_sem to avoid deadlock with ext4_get_blocks At this | |
202 | * moment, get_block can be called only for blocks inside i_size since | |
203 | * page cache has been already dropped and writes are blocked by | |
204 | * i_mutex. So we can safely drop the i_data_sem here. | |
205 | */ | |
0390131b | 206 | BUG_ON(EXT4_JOURNAL(inode) == NULL); |
ac27a0ec | 207 | jbd_debug(2, "restarting handle %p\n", handle); |
487caeef JK |
208 | up_write(&EXT4_I(inode)->i_data_sem); |
209 | ret = ext4_journal_restart(handle, blocks_for_truncate(inode)); | |
210 | down_write(&EXT4_I(inode)->i_data_sem); | |
211 | ||
212 | return ret; | |
ac27a0ec DK |
213 | } |
214 | ||
215 | /* | |
216 | * Called at the last iput() if i_nlink is zero. | |
217 | */ | |
af5bc92d | 218 | void ext4_delete_inode(struct inode *inode) |
ac27a0ec DK |
219 | { |
220 | handle_t *handle; | |
bc965ab3 | 221 | int err; |
ac27a0ec | 222 | |
678aaf48 JK |
223 | if (ext4_should_order_data(inode)) |
224 | ext4_begin_ordered_truncate(inode, 0); | |
ac27a0ec DK |
225 | truncate_inode_pages(&inode->i_data, 0); |
226 | ||
227 | if (is_bad_inode(inode)) | |
228 | goto no_delete; | |
229 | ||
bc965ab3 | 230 | handle = ext4_journal_start(inode, blocks_for_truncate(inode)+3); |
ac27a0ec | 231 | if (IS_ERR(handle)) { |
bc965ab3 | 232 | ext4_std_error(inode->i_sb, PTR_ERR(handle)); |
ac27a0ec DK |
233 | /* |
234 | * If we're going to skip the normal cleanup, we still need to | |
235 | * make sure that the in-core orphan linked list is properly | |
236 | * cleaned up. | |
237 | */ | |
617ba13b | 238 | ext4_orphan_del(NULL, inode); |
ac27a0ec DK |
239 | goto no_delete; |
240 | } | |
241 | ||
242 | if (IS_SYNC(inode)) | |
0390131b | 243 | ext4_handle_sync(handle); |
ac27a0ec | 244 | inode->i_size = 0; |
bc965ab3 TT |
245 | err = ext4_mark_inode_dirty(handle, inode); |
246 | if (err) { | |
247 | ext4_warning(inode->i_sb, __func__, | |
248 | "couldn't mark inode dirty (err %d)", err); | |
249 | goto stop_handle; | |
250 | } | |
ac27a0ec | 251 | if (inode->i_blocks) |
617ba13b | 252 | ext4_truncate(inode); |
bc965ab3 TT |
253 | |
254 | /* | |
255 | * ext4_ext_truncate() doesn't reserve any slop when it | |
256 | * restarts journal transactions; therefore there may not be | |
257 | * enough credits left in the handle to remove the inode from | |
258 | * the orphan list and set the dtime field. | |
259 | */ | |
0390131b | 260 | if (!ext4_handle_has_enough_credits(handle, 3)) { |
bc965ab3 TT |
261 | err = ext4_journal_extend(handle, 3); |
262 | if (err > 0) | |
263 | err = ext4_journal_restart(handle, 3); | |
264 | if (err != 0) { | |
265 | ext4_warning(inode->i_sb, __func__, | |
266 | "couldn't extend journal (err %d)", err); | |
267 | stop_handle: | |
268 | ext4_journal_stop(handle); | |
269 | goto no_delete; | |
270 | } | |
271 | } | |
272 | ||
ac27a0ec | 273 | /* |
617ba13b | 274 | * Kill off the orphan record which ext4_truncate created. |
ac27a0ec | 275 | * AKPM: I think this can be inside the above `if'. |
617ba13b | 276 | * Note that ext4_orphan_del() has to be able to cope with the |
ac27a0ec | 277 | * deletion of a non-existent orphan - this is because we don't |
617ba13b | 278 | * know if ext4_truncate() actually created an orphan record. |
ac27a0ec DK |
279 | * (Well, we could do this if we need to, but heck - it works) |
280 | */ | |
617ba13b MC |
281 | ext4_orphan_del(handle, inode); |
282 | EXT4_I(inode)->i_dtime = get_seconds(); | |
ac27a0ec DK |
283 | |
284 | /* | |
285 | * One subtle ordering requirement: if anything has gone wrong | |
286 | * (transaction abort, IO errors, whatever), then we can still | |
287 | * do these next steps (the fs will already have been marked as | |
288 | * having errors), but we can't free the inode if the mark_dirty | |
289 | * fails. | |
290 | */ | |
617ba13b | 291 | if (ext4_mark_inode_dirty(handle, inode)) |
ac27a0ec DK |
292 | /* If that failed, just do the required in-core inode clear. */ |
293 | clear_inode(inode); | |
294 | else | |
617ba13b MC |
295 | ext4_free_inode(handle, inode); |
296 | ext4_journal_stop(handle); | |
ac27a0ec DK |
297 | return; |
298 | no_delete: | |
299 | clear_inode(inode); /* We must guarantee clearing of inode... */ | |
300 | } | |
301 | ||
302 | typedef struct { | |
303 | __le32 *p; | |
304 | __le32 key; | |
305 | struct buffer_head *bh; | |
306 | } Indirect; | |
307 | ||
308 | static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) | |
309 | { | |
310 | p->key = *(p->p = v); | |
311 | p->bh = bh; | |
312 | } | |
313 | ||
ac27a0ec | 314 | /** |
617ba13b | 315 | * ext4_block_to_path - parse the block number into array of offsets |
ac27a0ec DK |
316 | * @inode: inode in question (we are only interested in its superblock) |
317 | * @i_block: block number to be parsed | |
318 | * @offsets: array to store the offsets in | |
8c55e204 DK |
319 | * @boundary: set this non-zero if the referred-to block is likely to be |
320 | * followed (on disk) by an indirect block. | |
ac27a0ec | 321 | * |
617ba13b | 322 | * To store the locations of file's data ext4 uses a data structure common |
ac27a0ec DK |
323 | * for UNIX filesystems - tree of pointers anchored in the inode, with |
324 | * data blocks at leaves and indirect blocks in intermediate nodes. | |
325 | * This function translates the block number into path in that tree - | |
326 | * return value is the path length and @offsets[n] is the offset of | |
327 | * pointer to (n+1)th node in the nth one. If @block is out of range | |
328 | * (negative or too large) warning is printed and zero returned. | |
329 | * | |
330 | * Note: function doesn't find node addresses, so no IO is needed. All | |
331 | * we need to know is the capacity of indirect blocks (taken from the | |
332 | * inode->i_sb). | |
333 | */ | |
334 | ||
335 | /* | |
336 | * Portability note: the last comparison (check that we fit into triple | |
337 | * indirect block) is spelled differently, because otherwise on an | |
338 | * architecture with 32-bit longs and 8Kb pages we might get into trouble | |
339 | * if our filesystem had 8Kb blocks. We might use long long, but that would | |
340 | * kill us on x86. Oh, well, at least the sign propagation does not matter - | |
341 | * i_block would have to be negative in the very beginning, so we would not | |
342 | * get there at all. | |
343 | */ | |
344 | ||
617ba13b | 345 | static int ext4_block_to_path(struct inode *inode, |
de9a55b8 TT |
346 | ext4_lblk_t i_block, |
347 | ext4_lblk_t offsets[4], int *boundary) | |
ac27a0ec | 348 | { |
617ba13b MC |
349 | int ptrs = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
350 | int ptrs_bits = EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb); | |
351 | const long direct_blocks = EXT4_NDIR_BLOCKS, | |
ac27a0ec DK |
352 | indirect_blocks = ptrs, |
353 | double_blocks = (1 << (ptrs_bits * 2)); | |
354 | int n = 0; | |
355 | int final = 0; | |
356 | ||
c333e073 | 357 | if (i_block < direct_blocks) { |
ac27a0ec DK |
358 | offsets[n++] = i_block; |
359 | final = direct_blocks; | |
af5bc92d | 360 | } else if ((i_block -= direct_blocks) < indirect_blocks) { |
617ba13b | 361 | offsets[n++] = EXT4_IND_BLOCK; |
ac27a0ec DK |
362 | offsets[n++] = i_block; |
363 | final = ptrs; | |
364 | } else if ((i_block -= indirect_blocks) < double_blocks) { | |
617ba13b | 365 | offsets[n++] = EXT4_DIND_BLOCK; |
ac27a0ec DK |
366 | offsets[n++] = i_block >> ptrs_bits; |
367 | offsets[n++] = i_block & (ptrs - 1); | |
368 | final = ptrs; | |
369 | } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { | |
617ba13b | 370 | offsets[n++] = EXT4_TIND_BLOCK; |
ac27a0ec DK |
371 | offsets[n++] = i_block >> (ptrs_bits * 2); |
372 | offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); | |
373 | offsets[n++] = i_block & (ptrs - 1); | |
374 | final = ptrs; | |
375 | } else { | |
e2b46574 | 376 | ext4_warning(inode->i_sb, "ext4_block_to_path", |
de9a55b8 TT |
377 | "block %lu > max in inode %lu", |
378 | i_block + direct_blocks + | |
379 | indirect_blocks + double_blocks, inode->i_ino); | |
ac27a0ec DK |
380 | } |
381 | if (boundary) | |
382 | *boundary = final - 1 - (i_block & (ptrs - 1)); | |
383 | return n; | |
384 | } | |
385 | ||
fe2c8191 | 386 | static int __ext4_check_blockref(const char *function, struct inode *inode, |
6fd058f7 TT |
387 | __le32 *p, unsigned int max) |
388 | { | |
f73953c0 | 389 | __le32 *bref = p; |
6fd058f7 TT |
390 | unsigned int blk; |
391 | ||
fe2c8191 | 392 | while (bref < p+max) { |
6fd058f7 | 393 | blk = le32_to_cpu(*bref++); |
de9a55b8 TT |
394 | if (blk && |
395 | unlikely(!ext4_data_block_valid(EXT4_SB(inode->i_sb), | |
6fd058f7 | 396 | blk, 1))) { |
fe2c8191 | 397 | ext4_error(inode->i_sb, function, |
6fd058f7 TT |
398 | "invalid block reference %u " |
399 | "in inode #%lu", blk, inode->i_ino); | |
de9a55b8 TT |
400 | return -EIO; |
401 | } | |
402 | } | |
403 | return 0; | |
fe2c8191 TN |
404 | } |
405 | ||
406 | ||
407 | #define ext4_check_indirect_blockref(inode, bh) \ | |
de9a55b8 | 408 | __ext4_check_blockref(__func__, inode, (__le32 *)(bh)->b_data, \ |
fe2c8191 TN |
409 | EXT4_ADDR_PER_BLOCK((inode)->i_sb)) |
410 | ||
411 | #define ext4_check_inode_blockref(inode) \ | |
de9a55b8 | 412 | __ext4_check_blockref(__func__, inode, EXT4_I(inode)->i_data, \ |
fe2c8191 TN |
413 | EXT4_NDIR_BLOCKS) |
414 | ||
ac27a0ec | 415 | /** |
617ba13b | 416 | * ext4_get_branch - read the chain of indirect blocks leading to data |
ac27a0ec DK |
417 | * @inode: inode in question |
418 | * @depth: depth of the chain (1 - direct pointer, etc.) | |
419 | * @offsets: offsets of pointers in inode/indirect blocks | |
420 | * @chain: place to store the result | |
421 | * @err: here we store the error value | |
422 | * | |
423 | * Function fills the array of triples <key, p, bh> and returns %NULL | |
424 | * if everything went OK or the pointer to the last filled triple | |
425 | * (incomplete one) otherwise. Upon the return chain[i].key contains | |
426 | * the number of (i+1)-th block in the chain (as it is stored in memory, | |
427 | * i.e. little-endian 32-bit), chain[i].p contains the address of that | |
428 | * number (it points into struct inode for i==0 and into the bh->b_data | |
429 | * for i>0) and chain[i].bh points to the buffer_head of i-th indirect | |
430 | * block for i>0 and NULL for i==0. In other words, it holds the block | |
431 | * numbers of the chain, addresses they were taken from (and where we can | |
432 | * verify that chain did not change) and buffer_heads hosting these | |
433 | * numbers. | |
434 | * | |
435 | * Function stops when it stumbles upon zero pointer (absent block) | |
436 | * (pointer to last triple returned, *@err == 0) | |
437 | * or when it gets an IO error reading an indirect block | |
438 | * (ditto, *@err == -EIO) | |
ac27a0ec DK |
439 | * or when it reads all @depth-1 indirect blocks successfully and finds |
440 | * the whole chain, all way to the data (returns %NULL, *err == 0). | |
c278bfec AK |
441 | * |
442 | * Need to be called with | |
0e855ac8 | 443 | * down_read(&EXT4_I(inode)->i_data_sem) |
ac27a0ec | 444 | */ |
725d26d3 AK |
445 | static Indirect *ext4_get_branch(struct inode *inode, int depth, |
446 | ext4_lblk_t *offsets, | |
ac27a0ec DK |
447 | Indirect chain[4], int *err) |
448 | { | |
449 | struct super_block *sb = inode->i_sb; | |
450 | Indirect *p = chain; | |
451 | struct buffer_head *bh; | |
452 | ||
453 | *err = 0; | |
454 | /* i_data is not going away, no lock needed */ | |
af5bc92d | 455 | add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets); |
ac27a0ec DK |
456 | if (!p->key) |
457 | goto no_block; | |
458 | while (--depth) { | |
fe2c8191 TN |
459 | bh = sb_getblk(sb, le32_to_cpu(p->key)); |
460 | if (unlikely(!bh)) | |
ac27a0ec | 461 | goto failure; |
de9a55b8 | 462 | |
fe2c8191 TN |
463 | if (!bh_uptodate_or_lock(bh)) { |
464 | if (bh_submit_read(bh) < 0) { | |
465 | put_bh(bh); | |
466 | goto failure; | |
467 | } | |
468 | /* validate block references */ | |
469 | if (ext4_check_indirect_blockref(inode, bh)) { | |
470 | put_bh(bh); | |
471 | goto failure; | |
472 | } | |
473 | } | |
de9a55b8 | 474 | |
af5bc92d | 475 | add_chain(++p, bh, (__le32 *)bh->b_data + *++offsets); |
ac27a0ec DK |
476 | /* Reader: end */ |
477 | if (!p->key) | |
478 | goto no_block; | |
479 | } | |
480 | return NULL; | |
481 | ||
ac27a0ec DK |
482 | failure: |
483 | *err = -EIO; | |
484 | no_block: | |
485 | return p; | |
486 | } | |
487 | ||
488 | /** | |
617ba13b | 489 | * ext4_find_near - find a place for allocation with sufficient locality |
ac27a0ec DK |
490 | * @inode: owner |
491 | * @ind: descriptor of indirect block. | |
492 | * | |
1cc8dcf5 | 493 | * This function returns the preferred place for block allocation. |
ac27a0ec DK |
494 | * It is used when heuristic for sequential allocation fails. |
495 | * Rules are: | |
496 | * + if there is a block to the left of our position - allocate near it. | |
497 | * + if pointer will live in indirect block - allocate near that block. | |
498 | * + if pointer will live in inode - allocate in the same | |
499 | * cylinder group. | |
500 | * | |
501 | * In the latter case we colour the starting block by the callers PID to | |
502 | * prevent it from clashing with concurrent allocations for a different inode | |
503 | * in the same block group. The PID is used here so that functionally related | |
504 | * files will be close-by on-disk. | |
505 | * | |
506 | * Caller must make sure that @ind is valid and will stay that way. | |
507 | */ | |
617ba13b | 508 | static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind) |
ac27a0ec | 509 | { |
617ba13b | 510 | struct ext4_inode_info *ei = EXT4_I(inode); |
af5bc92d | 511 | __le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data; |
ac27a0ec | 512 | __le32 *p; |
617ba13b | 513 | ext4_fsblk_t bg_start; |
74d3487f | 514 | ext4_fsblk_t last_block; |
617ba13b | 515 | ext4_grpblk_t colour; |
a4912123 TT |
516 | ext4_group_t block_group; |
517 | int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); | |
ac27a0ec DK |
518 | |
519 | /* Try to find previous block */ | |
520 | for (p = ind->p - 1; p >= start; p--) { | |
521 | if (*p) | |
522 | return le32_to_cpu(*p); | |
523 | } | |
524 | ||
525 | /* No such thing, so let's try location of indirect block */ | |
526 | if (ind->bh) | |
527 | return ind->bh->b_blocknr; | |
528 | ||
529 | /* | |
530 | * It is going to be referred to from the inode itself? OK, just put it | |
531 | * into the same cylinder group then. | |
532 | */ | |
a4912123 TT |
533 | block_group = ei->i_block_group; |
534 | if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { | |
535 | block_group &= ~(flex_size-1); | |
536 | if (S_ISREG(inode->i_mode)) | |
537 | block_group++; | |
538 | } | |
539 | bg_start = ext4_group_first_block_no(inode->i_sb, block_group); | |
74d3487f VC |
540 | last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; |
541 | ||
a4912123 TT |
542 | /* |
543 | * If we are doing delayed allocation, we don't need take | |
544 | * colour into account. | |
545 | */ | |
546 | if (test_opt(inode->i_sb, DELALLOC)) | |
547 | return bg_start; | |
548 | ||
74d3487f VC |
549 | if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) |
550 | colour = (current->pid % 16) * | |
617ba13b | 551 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
74d3487f VC |
552 | else |
553 | colour = (current->pid % 16) * ((last_block - bg_start) / 16); | |
ac27a0ec DK |
554 | return bg_start + colour; |
555 | } | |
556 | ||
557 | /** | |
1cc8dcf5 | 558 | * ext4_find_goal - find a preferred place for allocation. |
ac27a0ec DK |
559 | * @inode: owner |
560 | * @block: block we want | |
ac27a0ec | 561 | * @partial: pointer to the last triple within a chain |
ac27a0ec | 562 | * |
1cc8dcf5 | 563 | * Normally this function find the preferred place for block allocation, |
fb01bfda | 564 | * returns it. |
ac27a0ec | 565 | */ |
725d26d3 | 566 | static ext4_fsblk_t ext4_find_goal(struct inode *inode, ext4_lblk_t block, |
de9a55b8 | 567 | Indirect *partial) |
ac27a0ec | 568 | { |
ac27a0ec | 569 | /* |
c2ea3fde | 570 | * XXX need to get goal block from mballoc's data structures |
ac27a0ec | 571 | */ |
ac27a0ec | 572 | |
617ba13b | 573 | return ext4_find_near(inode, partial); |
ac27a0ec DK |
574 | } |
575 | ||
576 | /** | |
617ba13b | 577 | * ext4_blks_to_allocate: Look up the block map and count the number |
ac27a0ec DK |
578 | * of direct blocks need to be allocated for the given branch. |
579 | * | |
580 | * @branch: chain of indirect blocks | |
581 | * @k: number of blocks need for indirect blocks | |
582 | * @blks: number of data blocks to be mapped. | |
583 | * @blocks_to_boundary: the offset in the indirect block | |
584 | * | |
585 | * return the total number of blocks to be allocate, including the | |
586 | * direct and indirect blocks. | |
587 | */ | |
498e5f24 | 588 | static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned int blks, |
de9a55b8 | 589 | int blocks_to_boundary) |
ac27a0ec | 590 | { |
498e5f24 | 591 | unsigned int count = 0; |
ac27a0ec DK |
592 | |
593 | /* | |
594 | * Simple case, [t,d]Indirect block(s) has not allocated yet | |
595 | * then it's clear blocks on that path have not allocated | |
596 | */ | |
597 | if (k > 0) { | |
598 | /* right now we don't handle cross boundary allocation */ | |
599 | if (blks < blocks_to_boundary + 1) | |
600 | count += blks; | |
601 | else | |
602 | count += blocks_to_boundary + 1; | |
603 | return count; | |
604 | } | |
605 | ||
606 | count++; | |
607 | while (count < blks && count <= blocks_to_boundary && | |
608 | le32_to_cpu(*(branch[0].p + count)) == 0) { | |
609 | count++; | |
610 | } | |
611 | return count; | |
612 | } | |
613 | ||
614 | /** | |
617ba13b | 615 | * ext4_alloc_blocks: multiple allocate blocks needed for a branch |
ac27a0ec DK |
616 | * @indirect_blks: the number of blocks need to allocate for indirect |
617 | * blocks | |
618 | * | |
619 | * @new_blocks: on return it will store the new block numbers for | |
620 | * the indirect blocks(if needed) and the first direct block, | |
621 | * @blks: on return it will store the total number of allocated | |
622 | * direct blocks | |
623 | */ | |
617ba13b | 624 | static int ext4_alloc_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
625 | ext4_lblk_t iblock, ext4_fsblk_t goal, |
626 | int indirect_blks, int blks, | |
627 | ext4_fsblk_t new_blocks[4], int *err) | |
ac27a0ec | 628 | { |
815a1130 | 629 | struct ext4_allocation_request ar; |
ac27a0ec | 630 | int target, i; |
7061eba7 | 631 | unsigned long count = 0, blk_allocated = 0; |
ac27a0ec | 632 | int index = 0; |
617ba13b | 633 | ext4_fsblk_t current_block = 0; |
ac27a0ec DK |
634 | int ret = 0; |
635 | ||
636 | /* | |
637 | * Here we try to allocate the requested multiple blocks at once, | |
638 | * on a best-effort basis. | |
639 | * To build a branch, we should allocate blocks for | |
640 | * the indirect blocks(if not allocated yet), and at least | |
641 | * the first direct block of this branch. That's the | |
642 | * minimum number of blocks need to allocate(required) | |
643 | */ | |
7061eba7 AK |
644 | /* first we try to allocate the indirect blocks */ |
645 | target = indirect_blks; | |
646 | while (target > 0) { | |
ac27a0ec DK |
647 | count = target; |
648 | /* allocating blocks for indirect blocks and direct blocks */ | |
7061eba7 AK |
649 | current_block = ext4_new_meta_blocks(handle, inode, |
650 | goal, &count, err); | |
ac27a0ec DK |
651 | if (*err) |
652 | goto failed_out; | |
653 | ||
654 | target -= count; | |
655 | /* allocate blocks for indirect blocks */ | |
656 | while (index < indirect_blks && count) { | |
657 | new_blocks[index++] = current_block++; | |
658 | count--; | |
659 | } | |
7061eba7 AK |
660 | if (count > 0) { |
661 | /* | |
662 | * save the new block number | |
663 | * for the first direct block | |
664 | */ | |
665 | new_blocks[index] = current_block; | |
666 | printk(KERN_INFO "%s returned more blocks than " | |
667 | "requested\n", __func__); | |
668 | WARN_ON(1); | |
ac27a0ec | 669 | break; |
7061eba7 | 670 | } |
ac27a0ec DK |
671 | } |
672 | ||
7061eba7 AK |
673 | target = blks - count ; |
674 | blk_allocated = count; | |
675 | if (!target) | |
676 | goto allocated; | |
677 | /* Now allocate data blocks */ | |
815a1130 TT |
678 | memset(&ar, 0, sizeof(ar)); |
679 | ar.inode = inode; | |
680 | ar.goal = goal; | |
681 | ar.len = target; | |
682 | ar.logical = iblock; | |
683 | if (S_ISREG(inode->i_mode)) | |
684 | /* enable in-core preallocation only for regular files */ | |
685 | ar.flags = EXT4_MB_HINT_DATA; | |
686 | ||
687 | current_block = ext4_mb_new_blocks(handle, &ar, err); | |
688 | ||
7061eba7 AK |
689 | if (*err && (target == blks)) { |
690 | /* | |
691 | * if the allocation failed and we didn't allocate | |
692 | * any blocks before | |
693 | */ | |
694 | goto failed_out; | |
695 | } | |
696 | if (!*err) { | |
697 | if (target == blks) { | |
de9a55b8 TT |
698 | /* |
699 | * save the new block number | |
700 | * for the first direct block | |
701 | */ | |
7061eba7 AK |
702 | new_blocks[index] = current_block; |
703 | } | |
815a1130 | 704 | blk_allocated += ar.len; |
7061eba7 AK |
705 | } |
706 | allocated: | |
ac27a0ec | 707 | /* total number of blocks allocated for direct blocks */ |
7061eba7 | 708 | ret = blk_allocated; |
ac27a0ec DK |
709 | *err = 0; |
710 | return ret; | |
711 | failed_out: | |
af5bc92d | 712 | for (i = 0; i < index; i++) |
c9de560d | 713 | ext4_free_blocks(handle, inode, new_blocks[i], 1, 0); |
ac27a0ec DK |
714 | return ret; |
715 | } | |
716 | ||
717 | /** | |
617ba13b | 718 | * ext4_alloc_branch - allocate and set up a chain of blocks. |
ac27a0ec DK |
719 | * @inode: owner |
720 | * @indirect_blks: number of allocated indirect blocks | |
721 | * @blks: number of allocated direct blocks | |
722 | * @offsets: offsets (in the blocks) to store the pointers to next. | |
723 | * @branch: place to store the chain in. | |
724 | * | |
725 | * This function allocates blocks, zeroes out all but the last one, | |
726 | * links them into chain and (if we are synchronous) writes them to disk. | |
727 | * In other words, it prepares a branch that can be spliced onto the | |
728 | * inode. It stores the information about that chain in the branch[], in | |
617ba13b | 729 | * the same format as ext4_get_branch() would do. We are calling it after |
ac27a0ec DK |
730 | * we had read the existing part of chain and partial points to the last |
731 | * triple of that (one with zero ->key). Upon the exit we have the same | |
617ba13b | 732 | * picture as after the successful ext4_get_block(), except that in one |
ac27a0ec DK |
733 | * place chain is disconnected - *branch->p is still zero (we did not |
734 | * set the last link), but branch->key contains the number that should | |
735 | * be placed into *branch->p to fill that gap. | |
736 | * | |
737 | * If allocation fails we free all blocks we've allocated (and forget | |
738 | * their buffer_heads) and return the error value the from failed | |
617ba13b | 739 | * ext4_alloc_block() (normally -ENOSPC). Otherwise we set the chain |
ac27a0ec DK |
740 | * as described above and return 0. |
741 | */ | |
617ba13b | 742 | static int ext4_alloc_branch(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
743 | ext4_lblk_t iblock, int indirect_blks, |
744 | int *blks, ext4_fsblk_t goal, | |
745 | ext4_lblk_t *offsets, Indirect *branch) | |
ac27a0ec DK |
746 | { |
747 | int blocksize = inode->i_sb->s_blocksize; | |
748 | int i, n = 0; | |
749 | int err = 0; | |
750 | struct buffer_head *bh; | |
751 | int num; | |
617ba13b MC |
752 | ext4_fsblk_t new_blocks[4]; |
753 | ext4_fsblk_t current_block; | |
ac27a0ec | 754 | |
7061eba7 | 755 | num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks, |
ac27a0ec DK |
756 | *blks, new_blocks, &err); |
757 | if (err) | |
758 | return err; | |
759 | ||
760 | branch[0].key = cpu_to_le32(new_blocks[0]); | |
761 | /* | |
762 | * metadata blocks and data blocks are allocated. | |
763 | */ | |
764 | for (n = 1; n <= indirect_blks; n++) { | |
765 | /* | |
766 | * Get buffer_head for parent block, zero it out | |
767 | * and set the pointer to new one, then send | |
768 | * parent to disk. | |
769 | */ | |
770 | bh = sb_getblk(inode->i_sb, new_blocks[n-1]); | |
771 | branch[n].bh = bh; | |
772 | lock_buffer(bh); | |
773 | BUFFER_TRACE(bh, "call get_create_access"); | |
617ba13b | 774 | err = ext4_journal_get_create_access(handle, bh); |
ac27a0ec | 775 | if (err) { |
6487a9d3 CW |
776 | /* Don't brelse(bh) here; it's done in |
777 | * ext4_journal_forget() below */ | |
ac27a0ec | 778 | unlock_buffer(bh); |
ac27a0ec DK |
779 | goto failed; |
780 | } | |
781 | ||
782 | memset(bh->b_data, 0, blocksize); | |
783 | branch[n].p = (__le32 *) bh->b_data + offsets[n]; | |
784 | branch[n].key = cpu_to_le32(new_blocks[n]); | |
785 | *branch[n].p = branch[n].key; | |
af5bc92d | 786 | if (n == indirect_blks) { |
ac27a0ec DK |
787 | current_block = new_blocks[n]; |
788 | /* | |
789 | * End of chain, update the last new metablock of | |
790 | * the chain to point to the new allocated | |
791 | * data blocks numbers | |
792 | */ | |
de9a55b8 | 793 | for (i = 1; i < num; i++) |
ac27a0ec DK |
794 | *(branch[n].p + i) = cpu_to_le32(++current_block); |
795 | } | |
796 | BUFFER_TRACE(bh, "marking uptodate"); | |
797 | set_buffer_uptodate(bh); | |
798 | unlock_buffer(bh); | |
799 | ||
0390131b FM |
800 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
801 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
802 | if (err) |
803 | goto failed; | |
804 | } | |
805 | *blks = num; | |
806 | return err; | |
807 | failed: | |
808 | /* Allocation failed, free what we already allocated */ | |
809 | for (i = 1; i <= n ; i++) { | |
dab291af | 810 | BUFFER_TRACE(branch[i].bh, "call jbd2_journal_forget"); |
617ba13b | 811 | ext4_journal_forget(handle, branch[i].bh); |
ac27a0ec | 812 | } |
af5bc92d | 813 | for (i = 0; i < indirect_blks; i++) |
c9de560d | 814 | ext4_free_blocks(handle, inode, new_blocks[i], 1, 0); |
ac27a0ec | 815 | |
c9de560d | 816 | ext4_free_blocks(handle, inode, new_blocks[i], num, 0); |
ac27a0ec DK |
817 | |
818 | return err; | |
819 | } | |
820 | ||
821 | /** | |
617ba13b | 822 | * ext4_splice_branch - splice the allocated branch onto inode. |
ac27a0ec DK |
823 | * @inode: owner |
824 | * @block: (logical) number of block we are adding | |
825 | * @chain: chain of indirect blocks (with a missing link - see | |
617ba13b | 826 | * ext4_alloc_branch) |
ac27a0ec DK |
827 | * @where: location of missing link |
828 | * @num: number of indirect blocks we are adding | |
829 | * @blks: number of direct blocks we are adding | |
830 | * | |
831 | * This function fills the missing link and does all housekeeping needed in | |
832 | * inode (->i_blocks, etc.). In case of success we end up with the full | |
833 | * chain to new block and return 0. | |
834 | */ | |
617ba13b | 835 | static int ext4_splice_branch(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
836 | ext4_lblk_t block, Indirect *where, int num, |
837 | int blks) | |
ac27a0ec DK |
838 | { |
839 | int i; | |
840 | int err = 0; | |
617ba13b | 841 | ext4_fsblk_t current_block; |
ac27a0ec | 842 | |
ac27a0ec DK |
843 | /* |
844 | * If we're splicing into a [td]indirect block (as opposed to the | |
845 | * inode) then we need to get write access to the [td]indirect block | |
846 | * before the splice. | |
847 | */ | |
848 | if (where->bh) { | |
849 | BUFFER_TRACE(where->bh, "get_write_access"); | |
617ba13b | 850 | err = ext4_journal_get_write_access(handle, where->bh); |
ac27a0ec DK |
851 | if (err) |
852 | goto err_out; | |
853 | } | |
854 | /* That's it */ | |
855 | ||
856 | *where->p = where->key; | |
857 | ||
858 | /* | |
859 | * Update the host buffer_head or inode to point to more just allocated | |
860 | * direct blocks blocks | |
861 | */ | |
862 | if (num == 0 && blks > 1) { | |
863 | current_block = le32_to_cpu(where->key) + 1; | |
864 | for (i = 1; i < blks; i++) | |
af5bc92d | 865 | *(where->p + i) = cpu_to_le32(current_block++); |
ac27a0ec DK |
866 | } |
867 | ||
ac27a0ec | 868 | /* We are done with atomic stuff, now do the rest of housekeeping */ |
ac27a0ec DK |
869 | /* had we spliced it onto indirect block? */ |
870 | if (where->bh) { | |
871 | /* | |
872 | * If we spliced it onto an indirect block, we haven't | |
873 | * altered the inode. Note however that if it is being spliced | |
874 | * onto an indirect block at the very end of the file (the | |
875 | * file is growing) then we *will* alter the inode to reflect | |
876 | * the new i_size. But that is not done here - it is done in | |
617ba13b | 877 | * generic_commit_write->__mark_inode_dirty->ext4_dirty_inode. |
ac27a0ec DK |
878 | */ |
879 | jbd_debug(5, "splicing indirect only\n"); | |
0390131b FM |
880 | BUFFER_TRACE(where->bh, "call ext4_handle_dirty_metadata"); |
881 | err = ext4_handle_dirty_metadata(handle, inode, where->bh); | |
ac27a0ec DK |
882 | if (err) |
883 | goto err_out; | |
884 | } else { | |
885 | /* | |
886 | * OK, we spliced it into the inode itself on a direct block. | |
ac27a0ec | 887 | */ |
41591750 | 888 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
889 | jbd_debug(5, "splicing direct\n"); |
890 | } | |
891 | return err; | |
892 | ||
893 | err_out: | |
894 | for (i = 1; i <= num; i++) { | |
dab291af | 895 | BUFFER_TRACE(where[i].bh, "call jbd2_journal_forget"); |
617ba13b | 896 | ext4_journal_forget(handle, where[i].bh); |
c9de560d AT |
897 | ext4_free_blocks(handle, inode, |
898 | le32_to_cpu(where[i-1].key), 1, 0); | |
ac27a0ec | 899 | } |
c9de560d | 900 | ext4_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks, 0); |
ac27a0ec DK |
901 | |
902 | return err; | |
903 | } | |
904 | ||
905 | /* | |
b920c755 TT |
906 | * The ext4_ind_get_blocks() function handles non-extents inodes |
907 | * (i.e., using the traditional indirect/double-indirect i_blocks | |
908 | * scheme) for ext4_get_blocks(). | |
909 | * | |
ac27a0ec DK |
910 | * Allocation strategy is simple: if we have to allocate something, we will |
911 | * have to go the whole way to leaf. So let's do it before attaching anything | |
912 | * to tree, set linkage between the newborn blocks, write them if sync is | |
913 | * required, recheck the path, free and repeat if check fails, otherwise | |
914 | * set the last missing link (that will protect us from any truncate-generated | |
915 | * removals - all blocks on the path are immune now) and possibly force the | |
916 | * write on the parent block. | |
917 | * That has a nice additional property: no special recovery from the failed | |
918 | * allocations is needed - we simply release blocks and do not touch anything | |
919 | * reachable from inode. | |
920 | * | |
921 | * `handle' can be NULL if create == 0. | |
922 | * | |
ac27a0ec DK |
923 | * return > 0, # of blocks mapped or allocated. |
924 | * return = 0, if plain lookup failed. | |
925 | * return < 0, error case. | |
c278bfec | 926 | * |
b920c755 TT |
927 | * The ext4_ind_get_blocks() function should be called with |
928 | * down_write(&EXT4_I(inode)->i_data_sem) if allocating filesystem | |
929 | * blocks (i.e., flags has EXT4_GET_BLOCKS_CREATE set) or | |
930 | * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system | |
931 | * blocks. | |
ac27a0ec | 932 | */ |
e4d996ca | 933 | static int ext4_ind_get_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
934 | ext4_lblk_t iblock, unsigned int maxblocks, |
935 | struct buffer_head *bh_result, | |
936 | int flags) | |
ac27a0ec DK |
937 | { |
938 | int err = -EIO; | |
725d26d3 | 939 | ext4_lblk_t offsets[4]; |
ac27a0ec DK |
940 | Indirect chain[4]; |
941 | Indirect *partial; | |
617ba13b | 942 | ext4_fsblk_t goal; |
ac27a0ec DK |
943 | int indirect_blks; |
944 | int blocks_to_boundary = 0; | |
945 | int depth; | |
ac27a0ec | 946 | int count = 0; |
617ba13b | 947 | ext4_fsblk_t first_block = 0; |
ac27a0ec | 948 | |
a86c6181 | 949 | J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)); |
c2177057 | 950 | J_ASSERT(handle != NULL || (flags & EXT4_GET_BLOCKS_CREATE) == 0); |
725d26d3 | 951 | depth = ext4_block_to_path(inode, iblock, offsets, |
de9a55b8 | 952 | &blocks_to_boundary); |
ac27a0ec DK |
953 | |
954 | if (depth == 0) | |
955 | goto out; | |
956 | ||
617ba13b | 957 | partial = ext4_get_branch(inode, depth, offsets, chain, &err); |
ac27a0ec DK |
958 | |
959 | /* Simplest case - block found, no allocation needed */ | |
960 | if (!partial) { | |
961 | first_block = le32_to_cpu(chain[depth - 1].key); | |
962 | clear_buffer_new(bh_result); | |
963 | count++; | |
964 | /*map more blocks*/ | |
965 | while (count < maxblocks && count <= blocks_to_boundary) { | |
617ba13b | 966 | ext4_fsblk_t blk; |
ac27a0ec | 967 | |
ac27a0ec DK |
968 | blk = le32_to_cpu(*(chain[depth-1].p + count)); |
969 | ||
970 | if (blk == first_block + count) | |
971 | count++; | |
972 | else | |
973 | break; | |
974 | } | |
c278bfec | 975 | goto got_it; |
ac27a0ec DK |
976 | } |
977 | ||
978 | /* Next simple case - plain lookup or failed read of indirect block */ | |
c2177057 | 979 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0 || err == -EIO) |
ac27a0ec DK |
980 | goto cleanup; |
981 | ||
ac27a0ec | 982 | /* |
c2ea3fde | 983 | * Okay, we need to do block allocation. |
ac27a0ec | 984 | */ |
fb01bfda | 985 | goal = ext4_find_goal(inode, iblock, partial); |
ac27a0ec DK |
986 | |
987 | /* the number of blocks need to allocate for [d,t]indirect blocks */ | |
988 | indirect_blks = (chain + depth) - partial - 1; | |
989 | ||
990 | /* | |
991 | * Next look up the indirect map to count the totoal number of | |
992 | * direct blocks to allocate for this branch. | |
993 | */ | |
617ba13b | 994 | count = ext4_blks_to_allocate(partial, indirect_blks, |
ac27a0ec DK |
995 | maxblocks, blocks_to_boundary); |
996 | /* | |
617ba13b | 997 | * Block out ext4_truncate while we alter the tree |
ac27a0ec | 998 | */ |
7061eba7 | 999 | err = ext4_alloc_branch(handle, inode, iblock, indirect_blks, |
de9a55b8 TT |
1000 | &count, goal, |
1001 | offsets + (partial - chain), partial); | |
ac27a0ec DK |
1002 | |
1003 | /* | |
617ba13b | 1004 | * The ext4_splice_branch call will free and forget any buffers |
ac27a0ec DK |
1005 | * on the new chain if there is a failure, but that risks using |
1006 | * up transaction credits, especially for bitmaps where the | |
1007 | * credits cannot be returned. Can we handle this somehow? We | |
1008 | * may need to return -EAGAIN upwards in the worst case. --sct | |
1009 | */ | |
1010 | if (!err) | |
617ba13b | 1011 | err = ext4_splice_branch(handle, inode, iblock, |
de9a55b8 TT |
1012 | partial, indirect_blks, count); |
1013 | else | |
ac27a0ec DK |
1014 | goto cleanup; |
1015 | ||
1016 | set_buffer_new(bh_result); | |
1017 | got_it: | |
1018 | map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); | |
1019 | if (count > blocks_to_boundary) | |
1020 | set_buffer_boundary(bh_result); | |
1021 | err = count; | |
1022 | /* Clean up and exit */ | |
1023 | partial = chain + depth - 1; /* the whole chain */ | |
1024 | cleanup: | |
1025 | while (partial > chain) { | |
1026 | BUFFER_TRACE(partial->bh, "call brelse"); | |
1027 | brelse(partial->bh); | |
1028 | partial--; | |
1029 | } | |
1030 | BUFFER_TRACE(bh_result, "returned"); | |
1031 | out: | |
1032 | return err; | |
1033 | } | |
1034 | ||
60e58e0f MC |
1035 | qsize_t ext4_get_reserved_space(struct inode *inode) |
1036 | { | |
1037 | unsigned long long total; | |
1038 | ||
1039 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
1040 | total = EXT4_I(inode)->i_reserved_data_blocks + | |
1041 | EXT4_I(inode)->i_reserved_meta_blocks; | |
1042 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1043 | ||
1044 | return total; | |
1045 | } | |
12219aea AK |
1046 | /* |
1047 | * Calculate the number of metadata blocks need to reserve | |
1048 | * to allocate @blocks for non extent file based file | |
1049 | */ | |
1050 | static int ext4_indirect_calc_metadata_amount(struct inode *inode, int blocks) | |
1051 | { | |
1052 | int icap = EXT4_ADDR_PER_BLOCK(inode->i_sb); | |
1053 | int ind_blks, dind_blks, tind_blks; | |
1054 | ||
1055 | /* number of new indirect blocks needed */ | |
1056 | ind_blks = (blocks + icap - 1) / icap; | |
1057 | ||
1058 | dind_blks = (ind_blks + icap - 1) / icap; | |
1059 | ||
1060 | tind_blks = 1; | |
1061 | ||
1062 | return ind_blks + dind_blks + tind_blks; | |
1063 | } | |
1064 | ||
1065 | /* | |
1066 | * Calculate the number of metadata blocks need to reserve | |
1067 | * to allocate given number of blocks | |
1068 | */ | |
1069 | static int ext4_calc_metadata_amount(struct inode *inode, int blocks) | |
1070 | { | |
cd213226 MC |
1071 | if (!blocks) |
1072 | return 0; | |
1073 | ||
12219aea AK |
1074 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) |
1075 | return ext4_ext_calc_metadata_amount(inode, blocks); | |
1076 | ||
1077 | return ext4_indirect_calc_metadata_amount(inode, blocks); | |
1078 | } | |
1079 | ||
1080 | static void ext4_da_update_reserve_space(struct inode *inode, int used) | |
1081 | { | |
1082 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
1083 | int total, mdb, mdb_free; | |
1084 | ||
1085 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
1086 | /* recalculate the number of metablocks still need to be reserved */ | |
1087 | total = EXT4_I(inode)->i_reserved_data_blocks - used; | |
1088 | mdb = ext4_calc_metadata_amount(inode, total); | |
1089 | ||
1090 | /* figure out how many metablocks to release */ | |
1091 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1092 | mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb; | |
1093 | ||
6bc6e63f AK |
1094 | if (mdb_free) { |
1095 | /* Account for allocated meta_blocks */ | |
1096 | mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks; | |
1097 | ||
1098 | /* update fs dirty blocks counter */ | |
1099 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free); | |
1100 | EXT4_I(inode)->i_allocated_meta_blocks = 0; | |
1101 | EXT4_I(inode)->i_reserved_meta_blocks = mdb; | |
1102 | } | |
12219aea AK |
1103 | |
1104 | /* update per-inode reservations */ | |
1105 | BUG_ON(used > EXT4_I(inode)->i_reserved_data_blocks); | |
1106 | EXT4_I(inode)->i_reserved_data_blocks -= used; | |
12219aea | 1107 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
60e58e0f MC |
1108 | |
1109 | /* | |
1110 | * free those over-booking quota for metadata blocks | |
1111 | */ | |
60e58e0f MC |
1112 | if (mdb_free) |
1113 | vfs_dq_release_reservation_block(inode, mdb_free); | |
d6014301 AK |
1114 | |
1115 | /* | |
1116 | * If we have done all the pending block allocations and if | |
1117 | * there aren't any writers on the inode, we can discard the | |
1118 | * inode's preallocations. | |
1119 | */ | |
1120 | if (!total && (atomic_read(&inode->i_writecount) == 0)) | |
1121 | ext4_discard_preallocations(inode); | |
12219aea AK |
1122 | } |
1123 | ||
6fd058f7 TT |
1124 | static int check_block_validity(struct inode *inode, sector_t logical, |
1125 | sector_t phys, int len) | |
1126 | { | |
1127 | if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), phys, len)) { | |
1128 | ext4_error(inode->i_sb, "check_block_validity", | |
1129 | "inode #%lu logical block %llu mapped to %llu " | |
1130 | "(size %d)", inode->i_ino, | |
1131 | (unsigned long long) logical, | |
1132 | (unsigned long long) phys, len); | |
1133 | WARN_ON(1); | |
1134 | return -EIO; | |
1135 | } | |
1136 | return 0; | |
1137 | } | |
1138 | ||
f5ab0d1f | 1139 | /* |
12b7ac17 | 1140 | * The ext4_get_blocks() function tries to look up the requested blocks, |
2b2d6d01 | 1141 | * and returns if the blocks are already mapped. |
f5ab0d1f | 1142 | * |
f5ab0d1f MC |
1143 | * Otherwise it takes the write lock of the i_data_sem and allocate blocks |
1144 | * and store the allocated blocks in the result buffer head and mark it | |
1145 | * mapped. | |
1146 | * | |
1147 | * If file type is extents based, it will call ext4_ext_get_blocks(), | |
e4d996ca | 1148 | * Otherwise, call with ext4_ind_get_blocks() to handle indirect mapping |
f5ab0d1f MC |
1149 | * based files |
1150 | * | |
1151 | * On success, it returns the number of blocks being mapped or allocate. | |
1152 | * if create==0 and the blocks are pre-allocated and uninitialized block, | |
1153 | * the result buffer head is unmapped. If the create ==1, it will make sure | |
1154 | * the buffer head is mapped. | |
1155 | * | |
1156 | * It returns 0 if plain look up failed (blocks have not been allocated), in | |
1157 | * that casem, buffer head is unmapped | |
1158 | * | |
1159 | * It returns the error in case of allocation failure. | |
1160 | */ | |
12b7ac17 TT |
1161 | int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block, |
1162 | unsigned int max_blocks, struct buffer_head *bh, | |
c2177057 | 1163 | int flags) |
0e855ac8 AK |
1164 | { |
1165 | int retval; | |
f5ab0d1f MC |
1166 | |
1167 | clear_buffer_mapped(bh); | |
2a8964d6 | 1168 | clear_buffer_unwritten(bh); |
f5ab0d1f | 1169 | |
4df3d265 | 1170 | /* |
b920c755 TT |
1171 | * Try to see if we can get the block without requesting a new |
1172 | * file system block. | |
4df3d265 AK |
1173 | */ |
1174 | down_read((&EXT4_I(inode)->i_data_sem)); | |
1175 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { | |
1176 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, | |
c2177057 | 1177 | bh, 0); |
0e855ac8 | 1178 | } else { |
e4d996ca | 1179 | retval = ext4_ind_get_blocks(handle, inode, block, max_blocks, |
c2177057 | 1180 | bh, 0); |
0e855ac8 | 1181 | } |
4df3d265 | 1182 | up_read((&EXT4_I(inode)->i_data_sem)); |
f5ab0d1f | 1183 | |
6fd058f7 | 1184 | if (retval > 0 && buffer_mapped(bh)) { |
de9a55b8 | 1185 | int ret = check_block_validity(inode, block, |
6fd058f7 TT |
1186 | bh->b_blocknr, retval); |
1187 | if (ret != 0) | |
1188 | return ret; | |
1189 | } | |
1190 | ||
f5ab0d1f | 1191 | /* If it is only a block(s) look up */ |
c2177057 | 1192 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) |
f5ab0d1f MC |
1193 | return retval; |
1194 | ||
1195 | /* | |
1196 | * Returns if the blocks have already allocated | |
1197 | * | |
1198 | * Note that if blocks have been preallocated | |
1199 | * ext4_ext_get_block() returns th create = 0 | |
1200 | * with buffer head unmapped. | |
1201 | */ | |
1202 | if (retval > 0 && buffer_mapped(bh)) | |
4df3d265 AK |
1203 | return retval; |
1204 | ||
2a8964d6 AK |
1205 | /* |
1206 | * When we call get_blocks without the create flag, the | |
1207 | * BH_Unwritten flag could have gotten set if the blocks | |
1208 | * requested were part of a uninitialized extent. We need to | |
1209 | * clear this flag now that we are committed to convert all or | |
1210 | * part of the uninitialized extent to be an initialized | |
1211 | * extent. This is because we need to avoid the combination | |
1212 | * of BH_Unwritten and BH_Mapped flags being simultaneously | |
1213 | * set on the buffer_head. | |
1214 | */ | |
1215 | clear_buffer_unwritten(bh); | |
1216 | ||
4df3d265 | 1217 | /* |
f5ab0d1f MC |
1218 | * New blocks allocate and/or writing to uninitialized extent |
1219 | * will possibly result in updating i_data, so we take | |
1220 | * the write lock of i_data_sem, and call get_blocks() | |
1221 | * with create == 1 flag. | |
4df3d265 AK |
1222 | */ |
1223 | down_write((&EXT4_I(inode)->i_data_sem)); | |
d2a17637 MC |
1224 | |
1225 | /* | |
1226 | * if the caller is from delayed allocation writeout path | |
1227 | * we have already reserved fs blocks for allocation | |
1228 | * let the underlying get_block() function know to | |
1229 | * avoid double accounting | |
1230 | */ | |
c2177057 | 1231 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) |
d2a17637 | 1232 | EXT4_I(inode)->i_delalloc_reserved_flag = 1; |
4df3d265 AK |
1233 | /* |
1234 | * We need to check for EXT4 here because migrate | |
1235 | * could have changed the inode type in between | |
1236 | */ | |
0e855ac8 AK |
1237 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
1238 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, | |
c2177057 | 1239 | bh, flags); |
0e855ac8 | 1240 | } else { |
e4d996ca | 1241 | retval = ext4_ind_get_blocks(handle, inode, block, |
c2177057 | 1242 | max_blocks, bh, flags); |
267e4db9 AK |
1243 | |
1244 | if (retval > 0 && buffer_new(bh)) { | |
1245 | /* | |
1246 | * We allocated new blocks which will result in | |
1247 | * i_data's format changing. Force the migrate | |
1248 | * to fail by clearing migrate flags | |
1249 | */ | |
1250 | EXT4_I(inode)->i_flags = EXT4_I(inode)->i_flags & | |
1251 | ~EXT4_EXT_MIGRATE; | |
1252 | } | |
0e855ac8 | 1253 | } |
d2a17637 | 1254 | |
2ac3b6e0 | 1255 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) |
d2a17637 | 1256 | EXT4_I(inode)->i_delalloc_reserved_flag = 0; |
2ac3b6e0 TT |
1257 | |
1258 | /* | |
1259 | * Update reserved blocks/metadata blocks after successful | |
1260 | * block allocation which had been deferred till now. | |
1261 | */ | |
1262 | if ((retval > 0) && (flags & EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE)) | |
1263 | ext4_da_update_reserve_space(inode, retval); | |
d2a17637 | 1264 | |
4df3d265 | 1265 | up_write((&EXT4_I(inode)->i_data_sem)); |
6fd058f7 | 1266 | if (retval > 0 && buffer_mapped(bh)) { |
de9a55b8 | 1267 | int ret = check_block_validity(inode, block, |
6fd058f7 TT |
1268 | bh->b_blocknr, retval); |
1269 | if (ret != 0) | |
1270 | return ret; | |
1271 | } | |
0e855ac8 AK |
1272 | return retval; |
1273 | } | |
1274 | ||
f3bd1f3f MC |
1275 | /* Maximum number of blocks we map for direct IO at once. */ |
1276 | #define DIO_MAX_BLOCKS 4096 | |
1277 | ||
6873fa0d ES |
1278 | int ext4_get_block(struct inode *inode, sector_t iblock, |
1279 | struct buffer_head *bh_result, int create) | |
ac27a0ec | 1280 | { |
3e4fdaf8 | 1281 | handle_t *handle = ext4_journal_current_handle(); |
7fb5409d | 1282 | int ret = 0, started = 0; |
ac27a0ec | 1283 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; |
f3bd1f3f | 1284 | int dio_credits; |
ac27a0ec | 1285 | |
7fb5409d JK |
1286 | if (create && !handle) { |
1287 | /* Direct IO write... */ | |
1288 | if (max_blocks > DIO_MAX_BLOCKS) | |
1289 | max_blocks = DIO_MAX_BLOCKS; | |
f3bd1f3f MC |
1290 | dio_credits = ext4_chunk_trans_blocks(inode, max_blocks); |
1291 | handle = ext4_journal_start(inode, dio_credits); | |
7fb5409d | 1292 | if (IS_ERR(handle)) { |
ac27a0ec | 1293 | ret = PTR_ERR(handle); |
7fb5409d | 1294 | goto out; |
ac27a0ec | 1295 | } |
7fb5409d | 1296 | started = 1; |
ac27a0ec DK |
1297 | } |
1298 | ||
12b7ac17 | 1299 | ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result, |
c2177057 | 1300 | create ? EXT4_GET_BLOCKS_CREATE : 0); |
7fb5409d JK |
1301 | if (ret > 0) { |
1302 | bh_result->b_size = (ret << inode->i_blkbits); | |
1303 | ret = 0; | |
ac27a0ec | 1304 | } |
7fb5409d JK |
1305 | if (started) |
1306 | ext4_journal_stop(handle); | |
1307 | out: | |
ac27a0ec DK |
1308 | return ret; |
1309 | } | |
1310 | ||
1311 | /* | |
1312 | * `handle' can be NULL if create is zero | |
1313 | */ | |
617ba13b | 1314 | struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, |
725d26d3 | 1315 | ext4_lblk_t block, int create, int *errp) |
ac27a0ec DK |
1316 | { |
1317 | struct buffer_head dummy; | |
1318 | int fatal = 0, err; | |
03f5d8bc | 1319 | int flags = 0; |
ac27a0ec DK |
1320 | |
1321 | J_ASSERT(handle != NULL || create == 0); | |
1322 | ||
1323 | dummy.b_state = 0; | |
1324 | dummy.b_blocknr = -1000; | |
1325 | buffer_trace_init(&dummy.b_history); | |
c2177057 TT |
1326 | if (create) |
1327 | flags |= EXT4_GET_BLOCKS_CREATE; | |
1328 | err = ext4_get_blocks(handle, inode, block, 1, &dummy, flags); | |
ac27a0ec | 1329 | /* |
c2177057 TT |
1330 | * ext4_get_blocks() returns number of blocks mapped. 0 in |
1331 | * case of a HOLE. | |
ac27a0ec DK |
1332 | */ |
1333 | if (err > 0) { | |
1334 | if (err > 1) | |
1335 | WARN_ON(1); | |
1336 | err = 0; | |
1337 | } | |
1338 | *errp = err; | |
1339 | if (!err && buffer_mapped(&dummy)) { | |
1340 | struct buffer_head *bh; | |
1341 | bh = sb_getblk(inode->i_sb, dummy.b_blocknr); | |
1342 | if (!bh) { | |
1343 | *errp = -EIO; | |
1344 | goto err; | |
1345 | } | |
1346 | if (buffer_new(&dummy)) { | |
1347 | J_ASSERT(create != 0); | |
ac39849d | 1348 | J_ASSERT(handle != NULL); |
ac27a0ec DK |
1349 | |
1350 | /* | |
1351 | * Now that we do not always journal data, we should | |
1352 | * keep in mind whether this should always journal the | |
1353 | * new buffer as metadata. For now, regular file | |
617ba13b | 1354 | * writes use ext4_get_block instead, so it's not a |
ac27a0ec DK |
1355 | * problem. |
1356 | */ | |
1357 | lock_buffer(bh); | |
1358 | BUFFER_TRACE(bh, "call get_create_access"); | |
617ba13b | 1359 | fatal = ext4_journal_get_create_access(handle, bh); |
ac27a0ec | 1360 | if (!fatal && !buffer_uptodate(bh)) { |
af5bc92d | 1361 | memset(bh->b_data, 0, inode->i_sb->s_blocksize); |
ac27a0ec DK |
1362 | set_buffer_uptodate(bh); |
1363 | } | |
1364 | unlock_buffer(bh); | |
0390131b FM |
1365 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
1366 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
1367 | if (!fatal) |
1368 | fatal = err; | |
1369 | } else { | |
1370 | BUFFER_TRACE(bh, "not a new buffer"); | |
1371 | } | |
1372 | if (fatal) { | |
1373 | *errp = fatal; | |
1374 | brelse(bh); | |
1375 | bh = NULL; | |
1376 | } | |
1377 | return bh; | |
1378 | } | |
1379 | err: | |
1380 | return NULL; | |
1381 | } | |
1382 | ||
617ba13b | 1383 | struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode, |
725d26d3 | 1384 | ext4_lblk_t block, int create, int *err) |
ac27a0ec | 1385 | { |
af5bc92d | 1386 | struct buffer_head *bh; |
ac27a0ec | 1387 | |
617ba13b | 1388 | bh = ext4_getblk(handle, inode, block, create, err); |
ac27a0ec DK |
1389 | if (!bh) |
1390 | return bh; | |
1391 | if (buffer_uptodate(bh)) | |
1392 | return bh; | |
1393 | ll_rw_block(READ_META, 1, &bh); | |
1394 | wait_on_buffer(bh); | |
1395 | if (buffer_uptodate(bh)) | |
1396 | return bh; | |
1397 | put_bh(bh); | |
1398 | *err = -EIO; | |
1399 | return NULL; | |
1400 | } | |
1401 | ||
af5bc92d TT |
1402 | static int walk_page_buffers(handle_t *handle, |
1403 | struct buffer_head *head, | |
1404 | unsigned from, | |
1405 | unsigned to, | |
1406 | int *partial, | |
1407 | int (*fn)(handle_t *handle, | |
1408 | struct buffer_head *bh)) | |
ac27a0ec DK |
1409 | { |
1410 | struct buffer_head *bh; | |
1411 | unsigned block_start, block_end; | |
1412 | unsigned blocksize = head->b_size; | |
1413 | int err, ret = 0; | |
1414 | struct buffer_head *next; | |
1415 | ||
af5bc92d TT |
1416 | for (bh = head, block_start = 0; |
1417 | ret == 0 && (bh != head || !block_start); | |
de9a55b8 | 1418 | block_start = block_end, bh = next) { |
ac27a0ec DK |
1419 | next = bh->b_this_page; |
1420 | block_end = block_start + blocksize; | |
1421 | if (block_end <= from || block_start >= to) { | |
1422 | if (partial && !buffer_uptodate(bh)) | |
1423 | *partial = 1; | |
1424 | continue; | |
1425 | } | |
1426 | err = (*fn)(handle, bh); | |
1427 | if (!ret) | |
1428 | ret = err; | |
1429 | } | |
1430 | return ret; | |
1431 | } | |
1432 | ||
1433 | /* | |
1434 | * To preserve ordering, it is essential that the hole instantiation and | |
1435 | * the data write be encapsulated in a single transaction. We cannot | |
617ba13b | 1436 | * close off a transaction and start a new one between the ext4_get_block() |
dab291af | 1437 | * and the commit_write(). So doing the jbd2_journal_start at the start of |
ac27a0ec DK |
1438 | * prepare_write() is the right place. |
1439 | * | |
617ba13b MC |
1440 | * Also, this function can nest inside ext4_writepage() -> |
1441 | * block_write_full_page(). In that case, we *know* that ext4_writepage() | |
ac27a0ec DK |
1442 | * has generated enough buffer credits to do the whole page. So we won't |
1443 | * block on the journal in that case, which is good, because the caller may | |
1444 | * be PF_MEMALLOC. | |
1445 | * | |
617ba13b | 1446 | * By accident, ext4 can be reentered when a transaction is open via |
ac27a0ec DK |
1447 | * quota file writes. If we were to commit the transaction while thus |
1448 | * reentered, there can be a deadlock - we would be holding a quota | |
1449 | * lock, and the commit would never complete if another thread had a | |
1450 | * transaction open and was blocking on the quota lock - a ranking | |
1451 | * violation. | |
1452 | * | |
dab291af | 1453 | * So what we do is to rely on the fact that jbd2_journal_stop/journal_start |
ac27a0ec DK |
1454 | * will _not_ run commit under these circumstances because handle->h_ref |
1455 | * is elevated. We'll still have enough credits for the tiny quotafile | |
1456 | * write. | |
1457 | */ | |
1458 | static int do_journal_get_write_access(handle_t *handle, | |
de9a55b8 | 1459 | struct buffer_head *bh) |
ac27a0ec DK |
1460 | { |
1461 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1462 | return 0; | |
617ba13b | 1463 | return ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
1464 | } |
1465 | ||
bfc1af65 | 1466 | static int ext4_write_begin(struct file *file, struct address_space *mapping, |
de9a55b8 TT |
1467 | loff_t pos, unsigned len, unsigned flags, |
1468 | struct page **pagep, void **fsdata) | |
ac27a0ec | 1469 | { |
af5bc92d | 1470 | struct inode *inode = mapping->host; |
1938a150 | 1471 | int ret, needed_blocks; |
ac27a0ec DK |
1472 | handle_t *handle; |
1473 | int retries = 0; | |
af5bc92d | 1474 | struct page *page; |
de9a55b8 | 1475 | pgoff_t index; |
af5bc92d | 1476 | unsigned from, to; |
bfc1af65 | 1477 | |
9bffad1e | 1478 | trace_ext4_write_begin(inode, pos, len, flags); |
1938a150 AK |
1479 | /* |
1480 | * Reserve one block more for addition to orphan list in case | |
1481 | * we allocate blocks but write fails for some reason | |
1482 | */ | |
1483 | needed_blocks = ext4_writepage_trans_blocks(inode) + 1; | |
de9a55b8 | 1484 | index = pos >> PAGE_CACHE_SHIFT; |
af5bc92d TT |
1485 | from = pos & (PAGE_CACHE_SIZE - 1); |
1486 | to = from + len; | |
ac27a0ec DK |
1487 | |
1488 | retry: | |
af5bc92d TT |
1489 | handle = ext4_journal_start(inode, needed_blocks); |
1490 | if (IS_ERR(handle)) { | |
1491 | ret = PTR_ERR(handle); | |
1492 | goto out; | |
7479d2b9 | 1493 | } |
ac27a0ec | 1494 | |
ebd3610b JK |
1495 | /* We cannot recurse into the filesystem as the transaction is already |
1496 | * started */ | |
1497 | flags |= AOP_FLAG_NOFS; | |
1498 | ||
54566b2c | 1499 | page = grab_cache_page_write_begin(mapping, index, flags); |
cf108bca JK |
1500 | if (!page) { |
1501 | ext4_journal_stop(handle); | |
1502 | ret = -ENOMEM; | |
1503 | goto out; | |
1504 | } | |
1505 | *pagep = page; | |
1506 | ||
bfc1af65 | 1507 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, |
ebd3610b | 1508 | ext4_get_block); |
bfc1af65 NP |
1509 | |
1510 | if (!ret && ext4_should_journal_data(inode)) { | |
ac27a0ec DK |
1511 | ret = walk_page_buffers(handle, page_buffers(page), |
1512 | from, to, NULL, do_journal_get_write_access); | |
1513 | } | |
bfc1af65 NP |
1514 | |
1515 | if (ret) { | |
af5bc92d | 1516 | unlock_page(page); |
af5bc92d | 1517 | page_cache_release(page); |
ae4d5372 AK |
1518 | /* |
1519 | * block_write_begin may have instantiated a few blocks | |
1520 | * outside i_size. Trim these off again. Don't need | |
1521 | * i_size_read because we hold i_mutex. | |
1938a150 AK |
1522 | * |
1523 | * Add inode to orphan list in case we crash before | |
1524 | * truncate finishes | |
ae4d5372 | 1525 | */ |
ffacfa7a | 1526 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
1938a150 AK |
1527 | ext4_orphan_add(handle, inode); |
1528 | ||
1529 | ext4_journal_stop(handle); | |
1530 | if (pos + len > inode->i_size) { | |
ffacfa7a | 1531 | ext4_truncate(inode); |
de9a55b8 | 1532 | /* |
ffacfa7a | 1533 | * If truncate failed early the inode might |
1938a150 AK |
1534 | * still be on the orphan list; we need to |
1535 | * make sure the inode is removed from the | |
1536 | * orphan list in that case. | |
1537 | */ | |
1538 | if (inode->i_nlink) | |
1539 | ext4_orphan_del(NULL, inode); | |
1540 | } | |
bfc1af65 NP |
1541 | } |
1542 | ||
617ba13b | 1543 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
ac27a0ec | 1544 | goto retry; |
7479d2b9 | 1545 | out: |
ac27a0ec DK |
1546 | return ret; |
1547 | } | |
1548 | ||
bfc1af65 NP |
1549 | /* For write_end() in data=journal mode */ |
1550 | static int write_end_fn(handle_t *handle, struct buffer_head *bh) | |
ac27a0ec DK |
1551 | { |
1552 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1553 | return 0; | |
1554 | set_buffer_uptodate(bh); | |
0390131b | 1555 | return ext4_handle_dirty_metadata(handle, NULL, bh); |
ac27a0ec DK |
1556 | } |
1557 | ||
f8514083 | 1558 | static int ext4_generic_write_end(struct file *file, |
de9a55b8 TT |
1559 | struct address_space *mapping, |
1560 | loff_t pos, unsigned len, unsigned copied, | |
1561 | struct page *page, void *fsdata) | |
f8514083 AK |
1562 | { |
1563 | int i_size_changed = 0; | |
1564 | struct inode *inode = mapping->host; | |
1565 | handle_t *handle = ext4_journal_current_handle(); | |
1566 | ||
1567 | copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); | |
1568 | ||
1569 | /* | |
1570 | * No need to use i_size_read() here, the i_size | |
1571 | * cannot change under us because we hold i_mutex. | |
1572 | * | |
1573 | * But it's important to update i_size while still holding page lock: | |
1574 | * page writeout could otherwise come in and zero beyond i_size. | |
1575 | */ | |
1576 | if (pos + copied > inode->i_size) { | |
1577 | i_size_write(inode, pos + copied); | |
1578 | i_size_changed = 1; | |
1579 | } | |
1580 | ||
1581 | if (pos + copied > EXT4_I(inode)->i_disksize) { | |
1582 | /* We need to mark inode dirty even if | |
1583 | * new_i_size is less that inode->i_size | |
1584 | * bu greater than i_disksize.(hint delalloc) | |
1585 | */ | |
1586 | ext4_update_i_disksize(inode, (pos + copied)); | |
1587 | i_size_changed = 1; | |
1588 | } | |
1589 | unlock_page(page); | |
1590 | page_cache_release(page); | |
1591 | ||
1592 | /* | |
1593 | * Don't mark the inode dirty under page lock. First, it unnecessarily | |
1594 | * makes the holding time of page lock longer. Second, it forces lock | |
1595 | * ordering of page lock and transaction start for journaling | |
1596 | * filesystems. | |
1597 | */ | |
1598 | if (i_size_changed) | |
1599 | ext4_mark_inode_dirty(handle, inode); | |
1600 | ||
1601 | return copied; | |
1602 | } | |
1603 | ||
ac27a0ec DK |
1604 | /* |
1605 | * We need to pick up the new inode size which generic_commit_write gave us | |
1606 | * `file' can be NULL - eg, when called from page_symlink(). | |
1607 | * | |
617ba13b | 1608 | * ext4 never places buffers on inode->i_mapping->private_list. metadata |
ac27a0ec DK |
1609 | * buffers are managed internally. |
1610 | */ | |
bfc1af65 | 1611 | static int ext4_ordered_write_end(struct file *file, |
de9a55b8 TT |
1612 | struct address_space *mapping, |
1613 | loff_t pos, unsigned len, unsigned copied, | |
1614 | struct page *page, void *fsdata) | |
ac27a0ec | 1615 | { |
617ba13b | 1616 | handle_t *handle = ext4_journal_current_handle(); |
cf108bca | 1617 | struct inode *inode = mapping->host; |
ac27a0ec DK |
1618 | int ret = 0, ret2; |
1619 | ||
9bffad1e | 1620 | trace_ext4_ordered_write_end(inode, pos, len, copied); |
678aaf48 | 1621 | ret = ext4_jbd2_file_inode(handle, inode); |
ac27a0ec DK |
1622 | |
1623 | if (ret == 0) { | |
f8514083 | 1624 | ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, |
bfc1af65 | 1625 | page, fsdata); |
f8a87d89 | 1626 | copied = ret2; |
ffacfa7a | 1627 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1628 | /* if we have allocated more blocks and copied |
1629 | * less. We will have blocks allocated outside | |
1630 | * inode->i_size. So truncate them | |
1631 | */ | |
1632 | ext4_orphan_add(handle, inode); | |
f8a87d89 RK |
1633 | if (ret2 < 0) |
1634 | ret = ret2; | |
ac27a0ec | 1635 | } |
617ba13b | 1636 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1637 | if (!ret) |
1638 | ret = ret2; | |
bfc1af65 | 1639 | |
f8514083 | 1640 | if (pos + len > inode->i_size) { |
ffacfa7a | 1641 | ext4_truncate(inode); |
de9a55b8 | 1642 | /* |
ffacfa7a | 1643 | * If truncate failed early the inode might still be |
f8514083 AK |
1644 | * on the orphan list; we need to make sure the inode |
1645 | * is removed from the orphan list in that case. | |
1646 | */ | |
1647 | if (inode->i_nlink) | |
1648 | ext4_orphan_del(NULL, inode); | |
1649 | } | |
1650 | ||
1651 | ||
bfc1af65 | 1652 | return ret ? ret : copied; |
ac27a0ec DK |
1653 | } |
1654 | ||
bfc1af65 | 1655 | static int ext4_writeback_write_end(struct file *file, |
de9a55b8 TT |
1656 | struct address_space *mapping, |
1657 | loff_t pos, unsigned len, unsigned copied, | |
1658 | struct page *page, void *fsdata) | |
ac27a0ec | 1659 | { |
617ba13b | 1660 | handle_t *handle = ext4_journal_current_handle(); |
cf108bca | 1661 | struct inode *inode = mapping->host; |
ac27a0ec | 1662 | int ret = 0, ret2; |
ac27a0ec | 1663 | |
9bffad1e | 1664 | trace_ext4_writeback_write_end(inode, pos, len, copied); |
f8514083 | 1665 | ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, |
bfc1af65 | 1666 | page, fsdata); |
f8a87d89 | 1667 | copied = ret2; |
ffacfa7a | 1668 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1669 | /* if we have allocated more blocks and copied |
1670 | * less. We will have blocks allocated outside | |
1671 | * inode->i_size. So truncate them | |
1672 | */ | |
1673 | ext4_orphan_add(handle, inode); | |
1674 | ||
f8a87d89 RK |
1675 | if (ret2 < 0) |
1676 | ret = ret2; | |
ac27a0ec | 1677 | |
617ba13b | 1678 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1679 | if (!ret) |
1680 | ret = ret2; | |
bfc1af65 | 1681 | |
f8514083 | 1682 | if (pos + len > inode->i_size) { |
ffacfa7a | 1683 | ext4_truncate(inode); |
de9a55b8 | 1684 | /* |
ffacfa7a | 1685 | * If truncate failed early the inode might still be |
f8514083 AK |
1686 | * on the orphan list; we need to make sure the inode |
1687 | * is removed from the orphan list in that case. | |
1688 | */ | |
1689 | if (inode->i_nlink) | |
1690 | ext4_orphan_del(NULL, inode); | |
1691 | } | |
1692 | ||
bfc1af65 | 1693 | return ret ? ret : copied; |
ac27a0ec DK |
1694 | } |
1695 | ||
bfc1af65 | 1696 | static int ext4_journalled_write_end(struct file *file, |
de9a55b8 TT |
1697 | struct address_space *mapping, |
1698 | loff_t pos, unsigned len, unsigned copied, | |
1699 | struct page *page, void *fsdata) | |
ac27a0ec | 1700 | { |
617ba13b | 1701 | handle_t *handle = ext4_journal_current_handle(); |
bfc1af65 | 1702 | struct inode *inode = mapping->host; |
ac27a0ec DK |
1703 | int ret = 0, ret2; |
1704 | int partial = 0; | |
bfc1af65 | 1705 | unsigned from, to; |
cf17fea6 | 1706 | loff_t new_i_size; |
ac27a0ec | 1707 | |
9bffad1e | 1708 | trace_ext4_journalled_write_end(inode, pos, len, copied); |
bfc1af65 NP |
1709 | from = pos & (PAGE_CACHE_SIZE - 1); |
1710 | to = from + len; | |
1711 | ||
1712 | if (copied < len) { | |
1713 | if (!PageUptodate(page)) | |
1714 | copied = 0; | |
1715 | page_zero_new_buffers(page, from+copied, to); | |
1716 | } | |
ac27a0ec DK |
1717 | |
1718 | ret = walk_page_buffers(handle, page_buffers(page), from, | |
bfc1af65 | 1719 | to, &partial, write_end_fn); |
ac27a0ec DK |
1720 | if (!partial) |
1721 | SetPageUptodate(page); | |
cf17fea6 AK |
1722 | new_i_size = pos + copied; |
1723 | if (new_i_size > inode->i_size) | |
bfc1af65 | 1724 | i_size_write(inode, pos+copied); |
617ba13b | 1725 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; |
cf17fea6 AK |
1726 | if (new_i_size > EXT4_I(inode)->i_disksize) { |
1727 | ext4_update_i_disksize(inode, new_i_size); | |
617ba13b | 1728 | ret2 = ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
1729 | if (!ret) |
1730 | ret = ret2; | |
1731 | } | |
bfc1af65 | 1732 | |
cf108bca | 1733 | unlock_page(page); |
f8514083 | 1734 | page_cache_release(page); |
ffacfa7a | 1735 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1736 | /* if we have allocated more blocks and copied |
1737 | * less. We will have blocks allocated outside | |
1738 | * inode->i_size. So truncate them | |
1739 | */ | |
1740 | ext4_orphan_add(handle, inode); | |
1741 | ||
617ba13b | 1742 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1743 | if (!ret) |
1744 | ret = ret2; | |
f8514083 | 1745 | if (pos + len > inode->i_size) { |
ffacfa7a | 1746 | ext4_truncate(inode); |
de9a55b8 | 1747 | /* |
ffacfa7a | 1748 | * If truncate failed early the inode might still be |
f8514083 AK |
1749 | * on the orphan list; we need to make sure the inode |
1750 | * is removed from the orphan list in that case. | |
1751 | */ | |
1752 | if (inode->i_nlink) | |
1753 | ext4_orphan_del(NULL, inode); | |
1754 | } | |
bfc1af65 NP |
1755 | |
1756 | return ret ? ret : copied; | |
ac27a0ec | 1757 | } |
d2a17637 MC |
1758 | |
1759 | static int ext4_da_reserve_space(struct inode *inode, int nrblocks) | |
1760 | { | |
030ba6bc | 1761 | int retries = 0; |
60e58e0f MC |
1762 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
1763 | unsigned long md_needed, mdblocks, total = 0; | |
d2a17637 MC |
1764 | |
1765 | /* | |
1766 | * recalculate the amount of metadata blocks to reserve | |
1767 | * in order to allocate nrblocks | |
1768 | * worse case is one extent per block | |
1769 | */ | |
030ba6bc | 1770 | repeat: |
d2a17637 MC |
1771 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
1772 | total = EXT4_I(inode)->i_reserved_data_blocks + nrblocks; | |
1773 | mdblocks = ext4_calc_metadata_amount(inode, total); | |
1774 | BUG_ON(mdblocks < EXT4_I(inode)->i_reserved_meta_blocks); | |
1775 | ||
1776 | md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks; | |
1777 | total = md_needed + nrblocks; | |
1778 | ||
60e58e0f MC |
1779 | /* |
1780 | * Make quota reservation here to prevent quota overflow | |
1781 | * later. Real quota accounting is done at pages writeout | |
1782 | * time. | |
1783 | */ | |
1784 | if (vfs_dq_reserve_block(inode, total)) { | |
1785 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1786 | return -EDQUOT; | |
1787 | } | |
1788 | ||
a30d542a | 1789 | if (ext4_claim_free_blocks(sbi, total)) { |
d2a17637 | 1790 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
030ba6bc AK |
1791 | if (ext4_should_retry_alloc(inode->i_sb, &retries)) { |
1792 | yield(); | |
1793 | goto repeat; | |
1794 | } | |
60e58e0f | 1795 | vfs_dq_release_reservation_block(inode, total); |
d2a17637 MC |
1796 | return -ENOSPC; |
1797 | } | |
d2a17637 MC |
1798 | EXT4_I(inode)->i_reserved_data_blocks += nrblocks; |
1799 | EXT4_I(inode)->i_reserved_meta_blocks = mdblocks; | |
1800 | ||
1801 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1802 | return 0; /* success */ | |
1803 | } | |
1804 | ||
12219aea | 1805 | static void ext4_da_release_space(struct inode *inode, int to_free) |
d2a17637 MC |
1806 | { |
1807 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
1808 | int total, mdb, mdb_free, release; | |
1809 | ||
cd213226 MC |
1810 | if (!to_free) |
1811 | return; /* Nothing to release, exit */ | |
1812 | ||
d2a17637 | 1813 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
cd213226 MC |
1814 | |
1815 | if (!EXT4_I(inode)->i_reserved_data_blocks) { | |
1816 | /* | |
1817 | * if there is no reserved blocks, but we try to free some | |
1818 | * then the counter is messed up somewhere. | |
1819 | * but since this function is called from invalidate | |
1820 | * page, it's harmless to return without any action | |
1821 | */ | |
1822 | printk(KERN_INFO "ext4 delalloc try to release %d reserved " | |
1823 | "blocks for inode %lu, but there is no reserved " | |
1824 | "data blocks\n", to_free, inode->i_ino); | |
1825 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1826 | return; | |
1827 | } | |
1828 | ||
d2a17637 | 1829 | /* recalculate the number of metablocks still need to be reserved */ |
12219aea | 1830 | total = EXT4_I(inode)->i_reserved_data_blocks - to_free; |
d2a17637 MC |
1831 | mdb = ext4_calc_metadata_amount(inode, total); |
1832 | ||
1833 | /* figure out how many metablocks to release */ | |
1834 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1835 | mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb; | |
1836 | ||
d2a17637 MC |
1837 | release = to_free + mdb_free; |
1838 | ||
6bc6e63f AK |
1839 | /* update fs dirty blocks counter for truncate case */ |
1840 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, release); | |
d2a17637 MC |
1841 | |
1842 | /* update per-inode reservations */ | |
12219aea AK |
1843 | BUG_ON(to_free > EXT4_I(inode)->i_reserved_data_blocks); |
1844 | EXT4_I(inode)->i_reserved_data_blocks -= to_free; | |
d2a17637 MC |
1845 | |
1846 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1847 | EXT4_I(inode)->i_reserved_meta_blocks = mdb; | |
d2a17637 | 1848 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
60e58e0f MC |
1849 | |
1850 | vfs_dq_release_reservation_block(inode, release); | |
d2a17637 MC |
1851 | } |
1852 | ||
1853 | static void ext4_da_page_release_reservation(struct page *page, | |
de9a55b8 | 1854 | unsigned long offset) |
d2a17637 MC |
1855 | { |
1856 | int to_release = 0; | |
1857 | struct buffer_head *head, *bh; | |
1858 | unsigned int curr_off = 0; | |
1859 | ||
1860 | head = page_buffers(page); | |
1861 | bh = head; | |
1862 | do { | |
1863 | unsigned int next_off = curr_off + bh->b_size; | |
1864 | ||
1865 | if ((offset <= curr_off) && (buffer_delay(bh))) { | |
1866 | to_release++; | |
1867 | clear_buffer_delay(bh); | |
1868 | } | |
1869 | curr_off = next_off; | |
1870 | } while ((bh = bh->b_this_page) != head); | |
12219aea | 1871 | ext4_da_release_space(page->mapping->host, to_release); |
d2a17637 | 1872 | } |
ac27a0ec | 1873 | |
64769240 AT |
1874 | /* |
1875 | * Delayed allocation stuff | |
1876 | */ | |
1877 | ||
64769240 AT |
1878 | /* |
1879 | * mpage_da_submit_io - walks through extent of pages and try to write | |
a1d6cc56 | 1880 | * them with writepage() call back |
64769240 AT |
1881 | * |
1882 | * @mpd->inode: inode | |
1883 | * @mpd->first_page: first page of the extent | |
1884 | * @mpd->next_page: page after the last page of the extent | |
64769240 AT |
1885 | * |
1886 | * By the time mpage_da_submit_io() is called we expect all blocks | |
1887 | * to be allocated. this may be wrong if allocation failed. | |
1888 | * | |
1889 | * As pages are already locked by write_cache_pages(), we can't use it | |
1890 | */ | |
1891 | static int mpage_da_submit_io(struct mpage_da_data *mpd) | |
1892 | { | |
22208ded | 1893 | long pages_skipped; |
791b7f08 AK |
1894 | struct pagevec pvec; |
1895 | unsigned long index, end; | |
1896 | int ret = 0, err, nr_pages, i; | |
1897 | struct inode *inode = mpd->inode; | |
1898 | struct address_space *mapping = inode->i_mapping; | |
64769240 AT |
1899 | |
1900 | BUG_ON(mpd->next_page <= mpd->first_page); | |
791b7f08 AK |
1901 | /* |
1902 | * We need to start from the first_page to the next_page - 1 | |
1903 | * to make sure we also write the mapped dirty buffer_heads. | |
8dc207c0 | 1904 | * If we look at mpd->b_blocknr we would only be looking |
791b7f08 AK |
1905 | * at the currently mapped buffer_heads. |
1906 | */ | |
64769240 AT |
1907 | index = mpd->first_page; |
1908 | end = mpd->next_page - 1; | |
1909 | ||
791b7f08 | 1910 | pagevec_init(&pvec, 0); |
64769240 | 1911 | while (index <= end) { |
791b7f08 | 1912 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); |
64769240 AT |
1913 | if (nr_pages == 0) |
1914 | break; | |
1915 | for (i = 0; i < nr_pages; i++) { | |
1916 | struct page *page = pvec.pages[i]; | |
1917 | ||
791b7f08 AK |
1918 | index = page->index; |
1919 | if (index > end) | |
1920 | break; | |
1921 | index++; | |
1922 | ||
1923 | BUG_ON(!PageLocked(page)); | |
1924 | BUG_ON(PageWriteback(page)); | |
1925 | ||
22208ded | 1926 | pages_skipped = mpd->wbc->pages_skipped; |
a1d6cc56 | 1927 | err = mapping->a_ops->writepage(page, mpd->wbc); |
22208ded AK |
1928 | if (!err && (pages_skipped == mpd->wbc->pages_skipped)) |
1929 | /* | |
1930 | * have successfully written the page | |
1931 | * without skipping the same | |
1932 | */ | |
a1d6cc56 | 1933 | mpd->pages_written++; |
64769240 AT |
1934 | /* |
1935 | * In error case, we have to continue because | |
1936 | * remaining pages are still locked | |
1937 | * XXX: unlock and re-dirty them? | |
1938 | */ | |
1939 | if (ret == 0) | |
1940 | ret = err; | |
1941 | } | |
1942 | pagevec_release(&pvec); | |
1943 | } | |
64769240 AT |
1944 | return ret; |
1945 | } | |
1946 | ||
1947 | /* | |
1948 | * mpage_put_bnr_to_bhs - walk blocks and assign them actual numbers | |
1949 | * | |
1950 | * @mpd->inode - inode to walk through | |
1951 | * @exbh->b_blocknr - first block on a disk | |
1952 | * @exbh->b_size - amount of space in bytes | |
1953 | * @logical - first logical block to start assignment with | |
1954 | * | |
1955 | * the function goes through all passed space and put actual disk | |
29fa89d0 | 1956 | * block numbers into buffer heads, dropping BH_Delay and BH_Unwritten |
64769240 AT |
1957 | */ |
1958 | static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical, | |
1959 | struct buffer_head *exbh) | |
1960 | { | |
1961 | struct inode *inode = mpd->inode; | |
1962 | struct address_space *mapping = inode->i_mapping; | |
1963 | int blocks = exbh->b_size >> inode->i_blkbits; | |
1964 | sector_t pblock = exbh->b_blocknr, cur_logical; | |
1965 | struct buffer_head *head, *bh; | |
a1d6cc56 | 1966 | pgoff_t index, end; |
64769240 AT |
1967 | struct pagevec pvec; |
1968 | int nr_pages, i; | |
1969 | ||
1970 | index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
1971 | end = (logical + blocks - 1) >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
1972 | cur_logical = index << (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
1973 | ||
1974 | pagevec_init(&pvec, 0); | |
1975 | ||
1976 | while (index <= end) { | |
1977 | /* XXX: optimize tail */ | |
1978 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); | |
1979 | if (nr_pages == 0) | |
1980 | break; | |
1981 | for (i = 0; i < nr_pages; i++) { | |
1982 | struct page *page = pvec.pages[i]; | |
1983 | ||
1984 | index = page->index; | |
1985 | if (index > end) | |
1986 | break; | |
1987 | index++; | |
1988 | ||
1989 | BUG_ON(!PageLocked(page)); | |
1990 | BUG_ON(PageWriteback(page)); | |
1991 | BUG_ON(!page_has_buffers(page)); | |
1992 | ||
1993 | bh = page_buffers(page); | |
1994 | head = bh; | |
1995 | ||
1996 | /* skip blocks out of the range */ | |
1997 | do { | |
1998 | if (cur_logical >= logical) | |
1999 | break; | |
2000 | cur_logical++; | |
2001 | } while ((bh = bh->b_this_page) != head); | |
2002 | ||
2003 | do { | |
2004 | if (cur_logical >= logical + blocks) | |
2005 | break; | |
29fa89d0 AK |
2006 | |
2007 | if (buffer_delay(bh) || | |
2008 | buffer_unwritten(bh)) { | |
2009 | ||
2010 | BUG_ON(bh->b_bdev != inode->i_sb->s_bdev); | |
2011 | ||
2012 | if (buffer_delay(bh)) { | |
2013 | clear_buffer_delay(bh); | |
2014 | bh->b_blocknr = pblock; | |
2015 | } else { | |
2016 | /* | |
2017 | * unwritten already should have | |
2018 | * blocknr assigned. Verify that | |
2019 | */ | |
2020 | clear_buffer_unwritten(bh); | |
2021 | BUG_ON(bh->b_blocknr != pblock); | |
2022 | } | |
2023 | ||
61628a3f | 2024 | } else if (buffer_mapped(bh)) |
64769240 | 2025 | BUG_ON(bh->b_blocknr != pblock); |
64769240 AT |
2026 | |
2027 | cur_logical++; | |
2028 | pblock++; | |
2029 | } while ((bh = bh->b_this_page) != head); | |
2030 | } | |
2031 | pagevec_release(&pvec); | |
2032 | } | |
2033 | } | |
2034 | ||
2035 | ||
2036 | /* | |
2037 | * __unmap_underlying_blocks - just a helper function to unmap | |
2038 | * set of blocks described by @bh | |
2039 | */ | |
2040 | static inline void __unmap_underlying_blocks(struct inode *inode, | |
2041 | struct buffer_head *bh) | |
2042 | { | |
2043 | struct block_device *bdev = inode->i_sb->s_bdev; | |
2044 | int blocks, i; | |
2045 | ||
2046 | blocks = bh->b_size >> inode->i_blkbits; | |
2047 | for (i = 0; i < blocks; i++) | |
2048 | unmap_underlying_metadata(bdev, bh->b_blocknr + i); | |
2049 | } | |
2050 | ||
c4a0c46e AK |
2051 | static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd, |
2052 | sector_t logical, long blk_cnt) | |
2053 | { | |
2054 | int nr_pages, i; | |
2055 | pgoff_t index, end; | |
2056 | struct pagevec pvec; | |
2057 | struct inode *inode = mpd->inode; | |
2058 | struct address_space *mapping = inode->i_mapping; | |
2059 | ||
2060 | index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2061 | end = (logical + blk_cnt - 1) >> | |
2062 | (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2063 | while (index <= end) { | |
2064 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); | |
2065 | if (nr_pages == 0) | |
2066 | break; | |
2067 | for (i = 0; i < nr_pages; i++) { | |
2068 | struct page *page = pvec.pages[i]; | |
2069 | index = page->index; | |
2070 | if (index > end) | |
2071 | break; | |
2072 | index++; | |
2073 | ||
2074 | BUG_ON(!PageLocked(page)); | |
2075 | BUG_ON(PageWriteback(page)); | |
2076 | block_invalidatepage(page, 0); | |
2077 | ClearPageUptodate(page); | |
2078 | unlock_page(page); | |
2079 | } | |
2080 | } | |
2081 | return; | |
2082 | } | |
2083 | ||
df22291f AK |
2084 | static void ext4_print_free_blocks(struct inode *inode) |
2085 | { | |
2086 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
2087 | printk(KERN_EMERG "Total free blocks count %lld\n", | |
2088 | ext4_count_free_blocks(inode->i_sb)); | |
2089 | printk(KERN_EMERG "Free/Dirty block details\n"); | |
2090 | printk(KERN_EMERG "free_blocks=%lld\n", | |
8f72fbdf | 2091 | (long long)percpu_counter_sum(&sbi->s_freeblocks_counter)); |
df22291f | 2092 | printk(KERN_EMERG "dirty_blocks=%lld\n", |
8f72fbdf | 2093 | (long long)percpu_counter_sum(&sbi->s_dirtyblocks_counter)); |
df22291f | 2094 | printk(KERN_EMERG "Block reservation details\n"); |
498e5f24 | 2095 | printk(KERN_EMERG "i_reserved_data_blocks=%u\n", |
df22291f | 2096 | EXT4_I(inode)->i_reserved_data_blocks); |
498e5f24 | 2097 | printk(KERN_EMERG "i_reserved_meta_blocks=%u\n", |
df22291f AK |
2098 | EXT4_I(inode)->i_reserved_meta_blocks); |
2099 | return; | |
2100 | } | |
2101 | ||
64769240 AT |
2102 | /* |
2103 | * mpage_da_map_blocks - go through given space | |
2104 | * | |
8dc207c0 | 2105 | * @mpd - bh describing space |
64769240 AT |
2106 | * |
2107 | * The function skips space we know is already mapped to disk blocks. | |
2108 | * | |
64769240 | 2109 | */ |
ed5bde0b | 2110 | static int mpage_da_map_blocks(struct mpage_da_data *mpd) |
64769240 | 2111 | { |
2ac3b6e0 | 2112 | int err, blks, get_blocks_flags; |
030ba6bc | 2113 | struct buffer_head new; |
2fa3cdfb TT |
2114 | sector_t next = mpd->b_blocknr; |
2115 | unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits; | |
2116 | loff_t disksize = EXT4_I(mpd->inode)->i_disksize; | |
2117 | handle_t *handle = NULL; | |
64769240 AT |
2118 | |
2119 | /* | |
2120 | * We consider only non-mapped and non-allocated blocks | |
2121 | */ | |
8dc207c0 | 2122 | if ((mpd->b_state & (1 << BH_Mapped)) && |
29fa89d0 AK |
2123 | !(mpd->b_state & (1 << BH_Delay)) && |
2124 | !(mpd->b_state & (1 << BH_Unwritten))) | |
c4a0c46e | 2125 | return 0; |
2fa3cdfb TT |
2126 | |
2127 | /* | |
2128 | * If we didn't accumulate anything to write simply return | |
2129 | */ | |
2130 | if (!mpd->b_size) | |
2131 | return 0; | |
2132 | ||
2133 | handle = ext4_journal_current_handle(); | |
2134 | BUG_ON(!handle); | |
2135 | ||
79ffab34 | 2136 | /* |
2ac3b6e0 TT |
2137 | * Call ext4_get_blocks() to allocate any delayed allocation |
2138 | * blocks, or to convert an uninitialized extent to be | |
2139 | * initialized (in the case where we have written into | |
2140 | * one or more preallocated blocks). | |
2141 | * | |
2142 | * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to | |
2143 | * indicate that we are on the delayed allocation path. This | |
2144 | * affects functions in many different parts of the allocation | |
2145 | * call path. This flag exists primarily because we don't | |
2146 | * want to change *many* call functions, so ext4_get_blocks() | |
2147 | * will set the magic i_delalloc_reserved_flag once the | |
2148 | * inode's allocation semaphore is taken. | |
2149 | * | |
2150 | * If the blocks in questions were delalloc blocks, set | |
2151 | * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting | |
2152 | * variables are updated after the blocks have been allocated. | |
79ffab34 | 2153 | */ |
2ac3b6e0 TT |
2154 | new.b_state = 0; |
2155 | get_blocks_flags = (EXT4_GET_BLOCKS_CREATE | | |
2156 | EXT4_GET_BLOCKS_DELALLOC_RESERVE); | |
2157 | if (mpd->b_state & (1 << BH_Delay)) | |
2158 | get_blocks_flags |= EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE; | |
2fa3cdfb | 2159 | blks = ext4_get_blocks(handle, mpd->inode, next, max_blocks, |
2ac3b6e0 | 2160 | &new, get_blocks_flags); |
2fa3cdfb TT |
2161 | if (blks < 0) { |
2162 | err = blks; | |
ed5bde0b TT |
2163 | /* |
2164 | * If get block returns with error we simply | |
2165 | * return. Later writepage will redirty the page and | |
2166 | * writepages will find the dirty page again | |
c4a0c46e AK |
2167 | */ |
2168 | if (err == -EAGAIN) | |
2169 | return 0; | |
df22291f AK |
2170 | |
2171 | if (err == -ENOSPC && | |
ed5bde0b | 2172 | ext4_count_free_blocks(mpd->inode->i_sb)) { |
df22291f AK |
2173 | mpd->retval = err; |
2174 | return 0; | |
2175 | } | |
2176 | ||
c4a0c46e | 2177 | /* |
ed5bde0b TT |
2178 | * get block failure will cause us to loop in |
2179 | * writepages, because a_ops->writepage won't be able | |
2180 | * to make progress. The page will be redirtied by | |
2181 | * writepage and writepages will again try to write | |
2182 | * the same. | |
c4a0c46e AK |
2183 | */ |
2184 | printk(KERN_EMERG "%s block allocation failed for inode %lu " | |
2185 | "at logical offset %llu with max blocks " | |
2186 | "%zd with error %d\n", | |
2187 | __func__, mpd->inode->i_ino, | |
2188 | (unsigned long long)next, | |
8dc207c0 | 2189 | mpd->b_size >> mpd->inode->i_blkbits, err); |
c4a0c46e AK |
2190 | printk(KERN_EMERG "This should not happen.!! " |
2191 | "Data will be lost\n"); | |
030ba6bc | 2192 | if (err == -ENOSPC) { |
df22291f | 2193 | ext4_print_free_blocks(mpd->inode); |
030ba6bc | 2194 | } |
2fa3cdfb | 2195 | /* invalidate all the pages */ |
c4a0c46e | 2196 | ext4_da_block_invalidatepages(mpd, next, |
8dc207c0 | 2197 | mpd->b_size >> mpd->inode->i_blkbits); |
c4a0c46e AK |
2198 | return err; |
2199 | } | |
2fa3cdfb TT |
2200 | BUG_ON(blks == 0); |
2201 | ||
2202 | new.b_size = (blks << mpd->inode->i_blkbits); | |
64769240 | 2203 | |
a1d6cc56 AK |
2204 | if (buffer_new(&new)) |
2205 | __unmap_underlying_blocks(mpd->inode, &new); | |
64769240 | 2206 | |
a1d6cc56 AK |
2207 | /* |
2208 | * If blocks are delayed marked, we need to | |
2209 | * put actual blocknr and drop delayed bit | |
2210 | */ | |
8dc207c0 TT |
2211 | if ((mpd->b_state & (1 << BH_Delay)) || |
2212 | (mpd->b_state & (1 << BH_Unwritten))) | |
a1d6cc56 | 2213 | mpage_put_bnr_to_bhs(mpd, next, &new); |
64769240 | 2214 | |
2fa3cdfb TT |
2215 | if (ext4_should_order_data(mpd->inode)) { |
2216 | err = ext4_jbd2_file_inode(handle, mpd->inode); | |
2217 | if (err) | |
2218 | return err; | |
2219 | } | |
2220 | ||
2221 | /* | |
03f5d8bc | 2222 | * Update on-disk size along with block allocation. |
2fa3cdfb TT |
2223 | */ |
2224 | disksize = ((loff_t) next + blks) << mpd->inode->i_blkbits; | |
2225 | if (disksize > i_size_read(mpd->inode)) | |
2226 | disksize = i_size_read(mpd->inode); | |
2227 | if (disksize > EXT4_I(mpd->inode)->i_disksize) { | |
2228 | ext4_update_i_disksize(mpd->inode, disksize); | |
2229 | return ext4_mark_inode_dirty(handle, mpd->inode); | |
2230 | } | |
2231 | ||
c4a0c46e | 2232 | return 0; |
64769240 AT |
2233 | } |
2234 | ||
bf068ee2 AK |
2235 | #define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \ |
2236 | (1 << BH_Delay) | (1 << BH_Unwritten)) | |
64769240 AT |
2237 | |
2238 | /* | |
2239 | * mpage_add_bh_to_extent - try to add one more block to extent of blocks | |
2240 | * | |
2241 | * @mpd->lbh - extent of blocks | |
2242 | * @logical - logical number of the block in the file | |
2243 | * @bh - bh of the block (used to access block's state) | |
2244 | * | |
2245 | * the function is used to collect contig. blocks in same state | |
2246 | */ | |
2247 | static void mpage_add_bh_to_extent(struct mpage_da_data *mpd, | |
8dc207c0 TT |
2248 | sector_t logical, size_t b_size, |
2249 | unsigned long b_state) | |
64769240 | 2250 | { |
64769240 | 2251 | sector_t next; |
8dc207c0 | 2252 | int nrblocks = mpd->b_size >> mpd->inode->i_blkbits; |
64769240 | 2253 | |
525f4ed8 MC |
2254 | /* check if thereserved journal credits might overflow */ |
2255 | if (!(EXT4_I(mpd->inode)->i_flags & EXT4_EXTENTS_FL)) { | |
2256 | if (nrblocks >= EXT4_MAX_TRANS_DATA) { | |
2257 | /* | |
2258 | * With non-extent format we are limited by the journal | |
2259 | * credit available. Total credit needed to insert | |
2260 | * nrblocks contiguous blocks is dependent on the | |
2261 | * nrblocks. So limit nrblocks. | |
2262 | */ | |
2263 | goto flush_it; | |
2264 | } else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) > | |
2265 | EXT4_MAX_TRANS_DATA) { | |
2266 | /* | |
2267 | * Adding the new buffer_head would make it cross the | |
2268 | * allowed limit for which we have journal credit | |
2269 | * reserved. So limit the new bh->b_size | |
2270 | */ | |
2271 | b_size = (EXT4_MAX_TRANS_DATA - nrblocks) << | |
2272 | mpd->inode->i_blkbits; | |
2273 | /* we will do mpage_da_submit_io in the next loop */ | |
2274 | } | |
2275 | } | |
64769240 AT |
2276 | /* |
2277 | * First block in the extent | |
2278 | */ | |
8dc207c0 TT |
2279 | if (mpd->b_size == 0) { |
2280 | mpd->b_blocknr = logical; | |
2281 | mpd->b_size = b_size; | |
2282 | mpd->b_state = b_state & BH_FLAGS; | |
64769240 AT |
2283 | return; |
2284 | } | |
2285 | ||
8dc207c0 | 2286 | next = mpd->b_blocknr + nrblocks; |
64769240 AT |
2287 | /* |
2288 | * Can we merge the block to our big extent? | |
2289 | */ | |
8dc207c0 TT |
2290 | if (logical == next && (b_state & BH_FLAGS) == mpd->b_state) { |
2291 | mpd->b_size += b_size; | |
64769240 AT |
2292 | return; |
2293 | } | |
2294 | ||
525f4ed8 | 2295 | flush_it: |
64769240 AT |
2296 | /* |
2297 | * We couldn't merge the block to our extent, so we | |
2298 | * need to flush current extent and start new one | |
2299 | */ | |
c4a0c46e AK |
2300 | if (mpage_da_map_blocks(mpd) == 0) |
2301 | mpage_da_submit_io(mpd); | |
a1d6cc56 AK |
2302 | mpd->io_done = 1; |
2303 | return; | |
64769240 AT |
2304 | } |
2305 | ||
c364b22c | 2306 | static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh) |
29fa89d0 | 2307 | { |
c364b22c | 2308 | return (buffer_delay(bh) || buffer_unwritten(bh)) && buffer_dirty(bh); |
29fa89d0 AK |
2309 | } |
2310 | ||
64769240 AT |
2311 | /* |
2312 | * __mpage_da_writepage - finds extent of pages and blocks | |
2313 | * | |
2314 | * @page: page to consider | |
2315 | * @wbc: not used, we just follow rules | |
2316 | * @data: context | |
2317 | * | |
2318 | * The function finds extents of pages and scan them for all blocks. | |
2319 | */ | |
2320 | static int __mpage_da_writepage(struct page *page, | |
2321 | struct writeback_control *wbc, void *data) | |
2322 | { | |
2323 | struct mpage_da_data *mpd = data; | |
2324 | struct inode *inode = mpd->inode; | |
8dc207c0 | 2325 | struct buffer_head *bh, *head; |
64769240 AT |
2326 | sector_t logical; |
2327 | ||
a1d6cc56 AK |
2328 | if (mpd->io_done) { |
2329 | /* | |
2330 | * Rest of the page in the page_vec | |
2331 | * redirty then and skip then. We will | |
2332 | * try to to write them again after | |
2333 | * starting a new transaction | |
2334 | */ | |
2335 | redirty_page_for_writepage(wbc, page); | |
2336 | unlock_page(page); | |
2337 | return MPAGE_DA_EXTENT_TAIL; | |
2338 | } | |
64769240 AT |
2339 | /* |
2340 | * Can we merge this page to current extent? | |
2341 | */ | |
2342 | if (mpd->next_page != page->index) { | |
2343 | /* | |
2344 | * Nope, we can't. So, we map non-allocated blocks | |
a1d6cc56 | 2345 | * and start IO on them using writepage() |
64769240 AT |
2346 | */ |
2347 | if (mpd->next_page != mpd->first_page) { | |
c4a0c46e AK |
2348 | if (mpage_da_map_blocks(mpd) == 0) |
2349 | mpage_da_submit_io(mpd); | |
a1d6cc56 AK |
2350 | /* |
2351 | * skip rest of the page in the page_vec | |
2352 | */ | |
2353 | mpd->io_done = 1; | |
2354 | redirty_page_for_writepage(wbc, page); | |
2355 | unlock_page(page); | |
2356 | return MPAGE_DA_EXTENT_TAIL; | |
64769240 AT |
2357 | } |
2358 | ||
2359 | /* | |
2360 | * Start next extent of pages ... | |
2361 | */ | |
2362 | mpd->first_page = page->index; | |
2363 | ||
2364 | /* | |
2365 | * ... and blocks | |
2366 | */ | |
8dc207c0 TT |
2367 | mpd->b_size = 0; |
2368 | mpd->b_state = 0; | |
2369 | mpd->b_blocknr = 0; | |
64769240 AT |
2370 | } |
2371 | ||
2372 | mpd->next_page = page->index + 1; | |
2373 | logical = (sector_t) page->index << | |
2374 | (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2375 | ||
2376 | if (!page_has_buffers(page)) { | |
8dc207c0 TT |
2377 | mpage_add_bh_to_extent(mpd, logical, PAGE_CACHE_SIZE, |
2378 | (1 << BH_Dirty) | (1 << BH_Uptodate)); | |
a1d6cc56 AK |
2379 | if (mpd->io_done) |
2380 | return MPAGE_DA_EXTENT_TAIL; | |
64769240 AT |
2381 | } else { |
2382 | /* | |
2383 | * Page with regular buffer heads, just add all dirty ones | |
2384 | */ | |
2385 | head = page_buffers(page); | |
2386 | bh = head; | |
2387 | do { | |
2388 | BUG_ON(buffer_locked(bh)); | |
791b7f08 AK |
2389 | /* |
2390 | * We need to try to allocate | |
2391 | * unmapped blocks in the same page. | |
2392 | * Otherwise we won't make progress | |
43ce1d23 | 2393 | * with the page in ext4_writepage |
791b7f08 | 2394 | */ |
c364b22c | 2395 | if (ext4_bh_delay_or_unwritten(NULL, bh)) { |
8dc207c0 TT |
2396 | mpage_add_bh_to_extent(mpd, logical, |
2397 | bh->b_size, | |
2398 | bh->b_state); | |
a1d6cc56 AK |
2399 | if (mpd->io_done) |
2400 | return MPAGE_DA_EXTENT_TAIL; | |
791b7f08 AK |
2401 | } else if (buffer_dirty(bh) && (buffer_mapped(bh))) { |
2402 | /* | |
2403 | * mapped dirty buffer. We need to update | |
2404 | * the b_state because we look at | |
2405 | * b_state in mpage_da_map_blocks. We don't | |
2406 | * update b_size because if we find an | |
2407 | * unmapped buffer_head later we need to | |
2408 | * use the b_state flag of that buffer_head. | |
2409 | */ | |
8dc207c0 TT |
2410 | if (mpd->b_size == 0) |
2411 | mpd->b_state = bh->b_state & BH_FLAGS; | |
a1d6cc56 | 2412 | } |
64769240 AT |
2413 | logical++; |
2414 | } while ((bh = bh->b_this_page) != head); | |
2415 | } | |
2416 | ||
2417 | return 0; | |
2418 | } | |
2419 | ||
64769240 | 2420 | /* |
b920c755 TT |
2421 | * This is a special get_blocks_t callback which is used by |
2422 | * ext4_da_write_begin(). It will either return mapped block or | |
2423 | * reserve space for a single block. | |
29fa89d0 AK |
2424 | * |
2425 | * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set. | |
2426 | * We also have b_blocknr = -1 and b_bdev initialized properly | |
2427 | * | |
2428 | * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set. | |
2429 | * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev | |
2430 | * initialized properly. | |
64769240 AT |
2431 | */ |
2432 | static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock, | |
2433 | struct buffer_head *bh_result, int create) | |
2434 | { | |
2435 | int ret = 0; | |
33b9817e AK |
2436 | sector_t invalid_block = ~((sector_t) 0xffff); |
2437 | ||
2438 | if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es)) | |
2439 | invalid_block = ~0; | |
64769240 AT |
2440 | |
2441 | BUG_ON(create == 0); | |
2442 | BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); | |
2443 | ||
2444 | /* | |
2445 | * first, we need to know whether the block is allocated already | |
2446 | * preallocated blocks are unmapped but should treated | |
2447 | * the same as allocated blocks. | |
2448 | */ | |
c2177057 | 2449 | ret = ext4_get_blocks(NULL, inode, iblock, 1, bh_result, 0); |
d2a17637 MC |
2450 | if ((ret == 0) && !buffer_delay(bh_result)) { |
2451 | /* the block isn't (pre)allocated yet, let's reserve space */ | |
64769240 AT |
2452 | /* |
2453 | * XXX: __block_prepare_write() unmaps passed block, | |
2454 | * is it OK? | |
2455 | */ | |
d2a17637 MC |
2456 | ret = ext4_da_reserve_space(inode, 1); |
2457 | if (ret) | |
2458 | /* not enough space to reserve */ | |
2459 | return ret; | |
2460 | ||
33b9817e | 2461 | map_bh(bh_result, inode->i_sb, invalid_block); |
64769240 AT |
2462 | set_buffer_new(bh_result); |
2463 | set_buffer_delay(bh_result); | |
2464 | } else if (ret > 0) { | |
2465 | bh_result->b_size = (ret << inode->i_blkbits); | |
29fa89d0 AK |
2466 | if (buffer_unwritten(bh_result)) { |
2467 | /* A delayed write to unwritten bh should | |
2468 | * be marked new and mapped. Mapped ensures | |
2469 | * that we don't do get_block multiple times | |
2470 | * when we write to the same offset and new | |
2471 | * ensures that we do proper zero out for | |
2472 | * partial write. | |
2473 | */ | |
9c1ee184 | 2474 | set_buffer_new(bh_result); |
29fa89d0 AK |
2475 | set_buffer_mapped(bh_result); |
2476 | } | |
64769240 AT |
2477 | ret = 0; |
2478 | } | |
2479 | ||
2480 | return ret; | |
2481 | } | |
61628a3f | 2482 | |
b920c755 TT |
2483 | /* |
2484 | * This function is used as a standard get_block_t calback function | |
2485 | * when there is no desire to allocate any blocks. It is used as a | |
2486 | * callback function for block_prepare_write(), nobh_writepage(), and | |
2487 | * block_write_full_page(). These functions should only try to map a | |
2488 | * single block at a time. | |
2489 | * | |
2490 | * Since this function doesn't do block allocations even if the caller | |
2491 | * requests it by passing in create=1, it is critically important that | |
2492 | * any caller checks to make sure that any buffer heads are returned | |
2493 | * by this function are either all already mapped or marked for | |
2494 | * delayed allocation before calling nobh_writepage() or | |
2495 | * block_write_full_page(). Otherwise, b_blocknr could be left | |
2496 | * unitialized, and the page write functions will be taken by | |
2497 | * surprise. | |
2498 | */ | |
2499 | static int noalloc_get_block_write(struct inode *inode, sector_t iblock, | |
f0e6c985 AK |
2500 | struct buffer_head *bh_result, int create) |
2501 | { | |
2502 | int ret = 0; | |
2503 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; | |
2504 | ||
a2dc52b5 TT |
2505 | BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); |
2506 | ||
f0e6c985 AK |
2507 | /* |
2508 | * we don't want to do block allocation in writepage | |
2509 | * so call get_block_wrap with create = 0 | |
2510 | */ | |
c2177057 | 2511 | ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0); |
f0e6c985 AK |
2512 | if (ret > 0) { |
2513 | bh_result->b_size = (ret << inode->i_blkbits); | |
2514 | ret = 0; | |
2515 | } | |
2516 | return ret; | |
61628a3f MC |
2517 | } |
2518 | ||
62e086be AK |
2519 | static int bget_one(handle_t *handle, struct buffer_head *bh) |
2520 | { | |
2521 | get_bh(bh); | |
2522 | return 0; | |
2523 | } | |
2524 | ||
2525 | static int bput_one(handle_t *handle, struct buffer_head *bh) | |
2526 | { | |
2527 | put_bh(bh); | |
2528 | return 0; | |
2529 | } | |
2530 | ||
2531 | static int __ext4_journalled_writepage(struct page *page, | |
2532 | struct writeback_control *wbc, | |
2533 | unsigned int len) | |
2534 | { | |
2535 | struct address_space *mapping = page->mapping; | |
2536 | struct inode *inode = mapping->host; | |
2537 | struct buffer_head *page_bufs; | |
2538 | handle_t *handle = NULL; | |
2539 | int ret = 0; | |
2540 | int err; | |
2541 | ||
2542 | page_bufs = page_buffers(page); | |
2543 | BUG_ON(!page_bufs); | |
2544 | walk_page_buffers(handle, page_bufs, 0, len, NULL, bget_one); | |
2545 | /* As soon as we unlock the page, it can go away, but we have | |
2546 | * references to buffers so we are safe */ | |
2547 | unlock_page(page); | |
2548 | ||
2549 | handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode)); | |
2550 | if (IS_ERR(handle)) { | |
2551 | ret = PTR_ERR(handle); | |
2552 | goto out; | |
2553 | } | |
2554 | ||
2555 | ret = walk_page_buffers(handle, page_bufs, 0, len, NULL, | |
2556 | do_journal_get_write_access); | |
2557 | ||
2558 | err = walk_page_buffers(handle, page_bufs, 0, len, NULL, | |
2559 | write_end_fn); | |
2560 | if (ret == 0) | |
2561 | ret = err; | |
2562 | err = ext4_journal_stop(handle); | |
2563 | if (!ret) | |
2564 | ret = err; | |
2565 | ||
2566 | walk_page_buffers(handle, page_bufs, 0, len, NULL, bput_one); | |
2567 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; | |
2568 | out: | |
2569 | return ret; | |
2570 | } | |
2571 | ||
61628a3f | 2572 | /* |
43ce1d23 AK |
2573 | * Note that we don't need to start a transaction unless we're journaling data |
2574 | * because we should have holes filled from ext4_page_mkwrite(). We even don't | |
2575 | * need to file the inode to the transaction's list in ordered mode because if | |
2576 | * we are writing back data added by write(), the inode is already there and if | |
2577 | * we are writing back data modified via mmap(), noone guarantees in which | |
2578 | * transaction the data will hit the disk. In case we are journaling data, we | |
2579 | * cannot start transaction directly because transaction start ranks above page | |
2580 | * lock so we have to do some magic. | |
2581 | * | |
b920c755 TT |
2582 | * This function can get called via... |
2583 | * - ext4_da_writepages after taking page lock (have journal handle) | |
2584 | * - journal_submit_inode_data_buffers (no journal handle) | |
2585 | * - shrink_page_list via pdflush (no journal handle) | |
2586 | * - grab_page_cache when doing write_begin (have journal handle) | |
43ce1d23 AK |
2587 | * |
2588 | * We don't do any block allocation in this function. If we have page with | |
2589 | * multiple blocks we need to write those buffer_heads that are mapped. This | |
2590 | * is important for mmaped based write. So if we do with blocksize 1K | |
2591 | * truncate(f, 1024); | |
2592 | * a = mmap(f, 0, 4096); | |
2593 | * a[0] = 'a'; | |
2594 | * truncate(f, 4096); | |
2595 | * we have in the page first buffer_head mapped via page_mkwrite call back | |
2596 | * but other bufer_heads would be unmapped but dirty(dirty done via the | |
2597 | * do_wp_page). So writepage should write the first block. If we modify | |
2598 | * the mmap area beyond 1024 we will again get a page_fault and the | |
2599 | * page_mkwrite callback will do the block allocation and mark the | |
2600 | * buffer_heads mapped. | |
2601 | * | |
2602 | * We redirty the page if we have any buffer_heads that is either delay or | |
2603 | * unwritten in the page. | |
2604 | * | |
2605 | * We can get recursively called as show below. | |
2606 | * | |
2607 | * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() -> | |
2608 | * ext4_writepage() | |
2609 | * | |
2610 | * But since we don't do any block allocation we should not deadlock. | |
2611 | * Page also have the dirty flag cleared so we don't get recurive page_lock. | |
61628a3f | 2612 | */ |
43ce1d23 | 2613 | static int ext4_writepage(struct page *page, |
62e086be | 2614 | struct writeback_control *wbc) |
64769240 | 2615 | { |
64769240 | 2616 | int ret = 0; |
61628a3f | 2617 | loff_t size; |
498e5f24 | 2618 | unsigned int len; |
61628a3f MC |
2619 | struct buffer_head *page_bufs; |
2620 | struct inode *inode = page->mapping->host; | |
2621 | ||
43ce1d23 | 2622 | trace_ext4_writepage(inode, page); |
f0e6c985 AK |
2623 | size = i_size_read(inode); |
2624 | if (page->index == size >> PAGE_CACHE_SHIFT) | |
2625 | len = size & ~PAGE_CACHE_MASK; | |
2626 | else | |
2627 | len = PAGE_CACHE_SIZE; | |
64769240 | 2628 | |
f0e6c985 | 2629 | if (page_has_buffers(page)) { |
61628a3f | 2630 | page_bufs = page_buffers(page); |
f0e6c985 | 2631 | if (walk_page_buffers(NULL, page_bufs, 0, len, NULL, |
c364b22c | 2632 | ext4_bh_delay_or_unwritten)) { |
61628a3f | 2633 | /* |
f0e6c985 AK |
2634 | * We don't want to do block allocation |
2635 | * So redirty the page and return | |
cd1aac32 AK |
2636 | * We may reach here when we do a journal commit |
2637 | * via journal_submit_inode_data_buffers. | |
2638 | * If we don't have mapping block we just ignore | |
f0e6c985 AK |
2639 | * them. We can also reach here via shrink_page_list |
2640 | */ | |
2641 | redirty_page_for_writepage(wbc, page); | |
2642 | unlock_page(page); | |
2643 | return 0; | |
2644 | } | |
2645 | } else { | |
2646 | /* | |
2647 | * The test for page_has_buffers() is subtle: | |
2648 | * We know the page is dirty but it lost buffers. That means | |
2649 | * that at some moment in time after write_begin()/write_end() | |
2650 | * has been called all buffers have been clean and thus they | |
2651 | * must have been written at least once. So they are all | |
2652 | * mapped and we can happily proceed with mapping them | |
2653 | * and writing the page. | |
2654 | * | |
2655 | * Try to initialize the buffer_heads and check whether | |
2656 | * all are mapped and non delay. We don't want to | |
2657 | * do block allocation here. | |
2658 | */ | |
b767e78a | 2659 | ret = block_prepare_write(page, 0, len, |
b920c755 | 2660 | noalloc_get_block_write); |
f0e6c985 AK |
2661 | if (!ret) { |
2662 | page_bufs = page_buffers(page); | |
2663 | /* check whether all are mapped and non delay */ | |
2664 | if (walk_page_buffers(NULL, page_bufs, 0, len, NULL, | |
c364b22c | 2665 | ext4_bh_delay_or_unwritten)) { |
f0e6c985 AK |
2666 | redirty_page_for_writepage(wbc, page); |
2667 | unlock_page(page); | |
2668 | return 0; | |
2669 | } | |
2670 | } else { | |
2671 | /* | |
2672 | * We can't do block allocation here | |
2673 | * so just redity the page and unlock | |
2674 | * and return | |
61628a3f | 2675 | */ |
61628a3f MC |
2676 | redirty_page_for_writepage(wbc, page); |
2677 | unlock_page(page); | |
2678 | return 0; | |
2679 | } | |
ed9b3e33 | 2680 | /* now mark the buffer_heads as dirty and uptodate */ |
b767e78a | 2681 | block_commit_write(page, 0, len); |
64769240 AT |
2682 | } |
2683 | ||
43ce1d23 AK |
2684 | if (PageChecked(page) && ext4_should_journal_data(inode)) { |
2685 | /* | |
2686 | * It's mmapped pagecache. Add buffers and journal it. There | |
2687 | * doesn't seem much point in redirtying the page here. | |
2688 | */ | |
2689 | ClearPageChecked(page); | |
2690 | return __ext4_journalled_writepage(page, wbc, len); | |
2691 | } | |
2692 | ||
64769240 | 2693 | if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) |
b920c755 | 2694 | ret = nobh_writepage(page, noalloc_get_block_write, wbc); |
64769240 | 2695 | else |
b920c755 TT |
2696 | ret = block_write_full_page(page, noalloc_get_block_write, |
2697 | wbc); | |
64769240 | 2698 | |
64769240 AT |
2699 | return ret; |
2700 | } | |
2701 | ||
61628a3f | 2702 | /* |
525f4ed8 MC |
2703 | * This is called via ext4_da_writepages() to |
2704 | * calulate the total number of credits to reserve to fit | |
2705 | * a single extent allocation into a single transaction, | |
2706 | * ext4_da_writpeages() will loop calling this before | |
2707 | * the block allocation. | |
61628a3f | 2708 | */ |
525f4ed8 MC |
2709 | |
2710 | static int ext4_da_writepages_trans_blocks(struct inode *inode) | |
2711 | { | |
2712 | int max_blocks = EXT4_I(inode)->i_reserved_data_blocks; | |
2713 | ||
2714 | /* | |
2715 | * With non-extent format the journal credit needed to | |
2716 | * insert nrblocks contiguous block is dependent on | |
2717 | * number of contiguous block. So we will limit | |
2718 | * number of contiguous block to a sane value | |
2719 | */ | |
2720 | if (!(inode->i_flags & EXT4_EXTENTS_FL) && | |
2721 | (max_blocks > EXT4_MAX_TRANS_DATA)) | |
2722 | max_blocks = EXT4_MAX_TRANS_DATA; | |
2723 | ||
2724 | return ext4_chunk_trans_blocks(inode, max_blocks); | |
2725 | } | |
61628a3f | 2726 | |
64769240 | 2727 | static int ext4_da_writepages(struct address_space *mapping, |
a1d6cc56 | 2728 | struct writeback_control *wbc) |
64769240 | 2729 | { |
22208ded AK |
2730 | pgoff_t index; |
2731 | int range_whole = 0; | |
61628a3f | 2732 | handle_t *handle = NULL; |
df22291f | 2733 | struct mpage_da_data mpd; |
5e745b04 | 2734 | struct inode *inode = mapping->host; |
22208ded | 2735 | int no_nrwrite_index_update; |
498e5f24 TT |
2736 | int pages_written = 0; |
2737 | long pages_skipped; | |
2acf2c26 | 2738 | int range_cyclic, cycled = 1, io_done = 0; |
5e745b04 | 2739 | int needed_blocks, ret = 0, nr_to_writebump = 0; |
de89de6e | 2740 | loff_t range_start = wbc->range_start; |
5e745b04 | 2741 | struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb); |
61628a3f | 2742 | |
9bffad1e | 2743 | trace_ext4_da_writepages(inode, wbc); |
ba80b101 | 2744 | |
61628a3f MC |
2745 | /* |
2746 | * No pages to write? This is mainly a kludge to avoid starting | |
2747 | * a transaction for special inodes like journal inode on last iput() | |
2748 | * because that could violate lock ordering on umount | |
2749 | */ | |
a1d6cc56 | 2750 | if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) |
61628a3f | 2751 | return 0; |
2a21e37e TT |
2752 | |
2753 | /* | |
2754 | * If the filesystem has aborted, it is read-only, so return | |
2755 | * right away instead of dumping stack traces later on that | |
2756 | * will obscure the real source of the problem. We test | |
4ab2f15b | 2757 | * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because |
2a21e37e TT |
2758 | * the latter could be true if the filesystem is mounted |
2759 | * read-only, and in that case, ext4_da_writepages should | |
2760 | * *never* be called, so if that ever happens, we would want | |
2761 | * the stack trace. | |
2762 | */ | |
4ab2f15b | 2763 | if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED)) |
2a21e37e TT |
2764 | return -EROFS; |
2765 | ||
5e745b04 AK |
2766 | /* |
2767 | * Make sure nr_to_write is >= sbi->s_mb_stream_request | |
2768 | * This make sure small files blocks are allocated in | |
2769 | * single attempt. This ensure that small files | |
2770 | * get less fragmented. | |
2771 | */ | |
2772 | if (wbc->nr_to_write < sbi->s_mb_stream_request) { | |
2773 | nr_to_writebump = sbi->s_mb_stream_request - wbc->nr_to_write; | |
2774 | wbc->nr_to_write = sbi->s_mb_stream_request; | |
2775 | } | |
22208ded AK |
2776 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) |
2777 | range_whole = 1; | |
61628a3f | 2778 | |
2acf2c26 AK |
2779 | range_cyclic = wbc->range_cyclic; |
2780 | if (wbc->range_cyclic) { | |
22208ded | 2781 | index = mapping->writeback_index; |
2acf2c26 AK |
2782 | if (index) |
2783 | cycled = 0; | |
2784 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
2785 | wbc->range_end = LLONG_MAX; | |
2786 | wbc->range_cyclic = 0; | |
2787 | } else | |
22208ded | 2788 | index = wbc->range_start >> PAGE_CACHE_SHIFT; |
a1d6cc56 | 2789 | |
df22291f AK |
2790 | mpd.wbc = wbc; |
2791 | mpd.inode = mapping->host; | |
2792 | ||
22208ded AK |
2793 | /* |
2794 | * we don't want write_cache_pages to update | |
2795 | * nr_to_write and writeback_index | |
2796 | */ | |
2797 | no_nrwrite_index_update = wbc->no_nrwrite_index_update; | |
2798 | wbc->no_nrwrite_index_update = 1; | |
2799 | pages_skipped = wbc->pages_skipped; | |
2800 | ||
2acf2c26 | 2801 | retry: |
22208ded | 2802 | while (!ret && wbc->nr_to_write > 0) { |
a1d6cc56 AK |
2803 | |
2804 | /* | |
2805 | * we insert one extent at a time. So we need | |
2806 | * credit needed for single extent allocation. | |
2807 | * journalled mode is currently not supported | |
2808 | * by delalloc | |
2809 | */ | |
2810 | BUG_ON(ext4_should_journal_data(inode)); | |
525f4ed8 | 2811 | needed_blocks = ext4_da_writepages_trans_blocks(inode); |
a1d6cc56 | 2812 | |
61628a3f MC |
2813 | /* start a new transaction*/ |
2814 | handle = ext4_journal_start(inode, needed_blocks); | |
2815 | if (IS_ERR(handle)) { | |
2816 | ret = PTR_ERR(handle); | |
2a21e37e | 2817 | printk(KERN_CRIT "%s: jbd2_start: " |
a1d6cc56 AK |
2818 | "%ld pages, ino %lu; err %d\n", __func__, |
2819 | wbc->nr_to_write, inode->i_ino, ret); | |
2820 | dump_stack(); | |
61628a3f MC |
2821 | goto out_writepages; |
2822 | } | |
f63e6005 TT |
2823 | |
2824 | /* | |
2825 | * Now call __mpage_da_writepage to find the next | |
2826 | * contiguous region of logical blocks that need | |
2827 | * blocks to be allocated by ext4. We don't actually | |
2828 | * submit the blocks for I/O here, even though | |
2829 | * write_cache_pages thinks it will, and will set the | |
2830 | * pages as clean for write before calling | |
2831 | * __mpage_da_writepage(). | |
2832 | */ | |
2833 | mpd.b_size = 0; | |
2834 | mpd.b_state = 0; | |
2835 | mpd.b_blocknr = 0; | |
2836 | mpd.first_page = 0; | |
2837 | mpd.next_page = 0; | |
2838 | mpd.io_done = 0; | |
2839 | mpd.pages_written = 0; | |
2840 | mpd.retval = 0; | |
2841 | ret = write_cache_pages(mapping, wbc, __mpage_da_writepage, | |
2842 | &mpd); | |
2843 | /* | |
2844 | * If we have a contigous extent of pages and we | |
2845 | * haven't done the I/O yet, map the blocks and submit | |
2846 | * them for I/O. | |
2847 | */ | |
2848 | if (!mpd.io_done && mpd.next_page != mpd.first_page) { | |
2849 | if (mpage_da_map_blocks(&mpd) == 0) | |
2850 | mpage_da_submit_io(&mpd); | |
2851 | mpd.io_done = 1; | |
2852 | ret = MPAGE_DA_EXTENT_TAIL; | |
2853 | } | |
b3a3ca8c | 2854 | trace_ext4_da_write_pages(inode, &mpd); |
f63e6005 | 2855 | wbc->nr_to_write -= mpd.pages_written; |
df22291f | 2856 | |
61628a3f | 2857 | ext4_journal_stop(handle); |
df22291f | 2858 | |
8f64b32e | 2859 | if ((mpd.retval == -ENOSPC) && sbi->s_journal) { |
22208ded AK |
2860 | /* commit the transaction which would |
2861 | * free blocks released in the transaction | |
2862 | * and try again | |
2863 | */ | |
df22291f | 2864 | jbd2_journal_force_commit_nested(sbi->s_journal); |
22208ded AK |
2865 | wbc->pages_skipped = pages_skipped; |
2866 | ret = 0; | |
2867 | } else if (ret == MPAGE_DA_EXTENT_TAIL) { | |
a1d6cc56 AK |
2868 | /* |
2869 | * got one extent now try with | |
2870 | * rest of the pages | |
2871 | */ | |
22208ded AK |
2872 | pages_written += mpd.pages_written; |
2873 | wbc->pages_skipped = pages_skipped; | |
a1d6cc56 | 2874 | ret = 0; |
2acf2c26 | 2875 | io_done = 1; |
22208ded | 2876 | } else if (wbc->nr_to_write) |
61628a3f MC |
2877 | /* |
2878 | * There is no more writeout needed | |
2879 | * or we requested for a noblocking writeout | |
2880 | * and we found the device congested | |
2881 | */ | |
61628a3f | 2882 | break; |
a1d6cc56 | 2883 | } |
2acf2c26 AK |
2884 | if (!io_done && !cycled) { |
2885 | cycled = 1; | |
2886 | index = 0; | |
2887 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
2888 | wbc->range_end = mapping->writeback_index - 1; | |
2889 | goto retry; | |
2890 | } | |
22208ded AK |
2891 | if (pages_skipped != wbc->pages_skipped) |
2892 | printk(KERN_EMERG "This should not happen leaving %s " | |
2893 | "with nr_to_write = %ld ret = %d\n", | |
2894 | __func__, wbc->nr_to_write, ret); | |
2895 | ||
2896 | /* Update index */ | |
2897 | index += pages_written; | |
2acf2c26 | 2898 | wbc->range_cyclic = range_cyclic; |
22208ded AK |
2899 | if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) |
2900 | /* | |
2901 | * set the writeback_index so that range_cyclic | |
2902 | * mode will write it back later | |
2903 | */ | |
2904 | mapping->writeback_index = index; | |
a1d6cc56 | 2905 | |
61628a3f | 2906 | out_writepages: |
22208ded AK |
2907 | if (!no_nrwrite_index_update) |
2908 | wbc->no_nrwrite_index_update = 0; | |
2909 | wbc->nr_to_write -= nr_to_writebump; | |
de89de6e | 2910 | wbc->range_start = range_start; |
9bffad1e | 2911 | trace_ext4_da_writepages_result(inode, wbc, ret, pages_written); |
61628a3f | 2912 | return ret; |
64769240 AT |
2913 | } |
2914 | ||
79f0be8d AK |
2915 | #define FALL_BACK_TO_NONDELALLOC 1 |
2916 | static int ext4_nonda_switch(struct super_block *sb) | |
2917 | { | |
2918 | s64 free_blocks, dirty_blocks; | |
2919 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2920 | ||
2921 | /* | |
2922 | * switch to non delalloc mode if we are running low | |
2923 | * on free block. The free block accounting via percpu | |
179f7ebf | 2924 | * counters can get slightly wrong with percpu_counter_batch getting |
79f0be8d AK |
2925 | * accumulated on each CPU without updating global counters |
2926 | * Delalloc need an accurate free block accounting. So switch | |
2927 | * to non delalloc when we are near to error range. | |
2928 | */ | |
2929 | free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter); | |
2930 | dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyblocks_counter); | |
2931 | if (2 * free_blocks < 3 * dirty_blocks || | |
2932 | free_blocks < (dirty_blocks + EXT4_FREEBLOCKS_WATERMARK)) { | |
2933 | /* | |
2934 | * free block count is less that 150% of dirty blocks | |
2935 | * or free blocks is less that watermark | |
2936 | */ | |
2937 | return 1; | |
2938 | } | |
2939 | return 0; | |
2940 | } | |
2941 | ||
64769240 | 2942 | static int ext4_da_write_begin(struct file *file, struct address_space *mapping, |
de9a55b8 TT |
2943 | loff_t pos, unsigned len, unsigned flags, |
2944 | struct page **pagep, void **fsdata) | |
64769240 | 2945 | { |
d2a17637 | 2946 | int ret, retries = 0; |
64769240 AT |
2947 | struct page *page; |
2948 | pgoff_t index; | |
2949 | unsigned from, to; | |
2950 | struct inode *inode = mapping->host; | |
2951 | handle_t *handle; | |
2952 | ||
2953 | index = pos >> PAGE_CACHE_SHIFT; | |
2954 | from = pos & (PAGE_CACHE_SIZE - 1); | |
2955 | to = from + len; | |
79f0be8d AK |
2956 | |
2957 | if (ext4_nonda_switch(inode->i_sb)) { | |
2958 | *fsdata = (void *)FALL_BACK_TO_NONDELALLOC; | |
2959 | return ext4_write_begin(file, mapping, pos, | |
2960 | len, flags, pagep, fsdata); | |
2961 | } | |
2962 | *fsdata = (void *)0; | |
9bffad1e | 2963 | trace_ext4_da_write_begin(inode, pos, len, flags); |
d2a17637 | 2964 | retry: |
64769240 AT |
2965 | /* |
2966 | * With delayed allocation, we don't log the i_disksize update | |
2967 | * if there is delayed block allocation. But we still need | |
2968 | * to journalling the i_disksize update if writes to the end | |
2969 | * of file which has an already mapped buffer. | |
2970 | */ | |
2971 | handle = ext4_journal_start(inode, 1); | |
2972 | if (IS_ERR(handle)) { | |
2973 | ret = PTR_ERR(handle); | |
2974 | goto out; | |
2975 | } | |
ebd3610b JK |
2976 | /* We cannot recurse into the filesystem as the transaction is already |
2977 | * started */ | |
2978 | flags |= AOP_FLAG_NOFS; | |
64769240 | 2979 | |
54566b2c | 2980 | page = grab_cache_page_write_begin(mapping, index, flags); |
d5a0d4f7 ES |
2981 | if (!page) { |
2982 | ext4_journal_stop(handle); | |
2983 | ret = -ENOMEM; | |
2984 | goto out; | |
2985 | } | |
64769240 AT |
2986 | *pagep = page; |
2987 | ||
2988 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, | |
b920c755 | 2989 | ext4_da_get_block_prep); |
64769240 AT |
2990 | if (ret < 0) { |
2991 | unlock_page(page); | |
2992 | ext4_journal_stop(handle); | |
2993 | page_cache_release(page); | |
ae4d5372 AK |
2994 | /* |
2995 | * block_write_begin may have instantiated a few blocks | |
2996 | * outside i_size. Trim these off again. Don't need | |
2997 | * i_size_read because we hold i_mutex. | |
2998 | */ | |
2999 | if (pos + len > inode->i_size) | |
ffacfa7a | 3000 | ext4_truncate(inode); |
64769240 AT |
3001 | } |
3002 | ||
d2a17637 MC |
3003 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
3004 | goto retry; | |
64769240 AT |
3005 | out: |
3006 | return ret; | |
3007 | } | |
3008 | ||
632eaeab MC |
3009 | /* |
3010 | * Check if we should update i_disksize | |
3011 | * when write to the end of file but not require block allocation | |
3012 | */ | |
3013 | static int ext4_da_should_update_i_disksize(struct page *page, | |
de9a55b8 | 3014 | unsigned long offset) |
632eaeab MC |
3015 | { |
3016 | struct buffer_head *bh; | |
3017 | struct inode *inode = page->mapping->host; | |
3018 | unsigned int idx; | |
3019 | int i; | |
3020 | ||
3021 | bh = page_buffers(page); | |
3022 | idx = offset >> inode->i_blkbits; | |
3023 | ||
af5bc92d | 3024 | for (i = 0; i < idx; i++) |
632eaeab MC |
3025 | bh = bh->b_this_page; |
3026 | ||
29fa89d0 | 3027 | if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh)) |
632eaeab MC |
3028 | return 0; |
3029 | return 1; | |
3030 | } | |
3031 | ||
64769240 | 3032 | static int ext4_da_write_end(struct file *file, |
de9a55b8 TT |
3033 | struct address_space *mapping, |
3034 | loff_t pos, unsigned len, unsigned copied, | |
3035 | struct page *page, void *fsdata) | |
64769240 AT |
3036 | { |
3037 | struct inode *inode = mapping->host; | |
3038 | int ret = 0, ret2; | |
3039 | handle_t *handle = ext4_journal_current_handle(); | |
3040 | loff_t new_i_size; | |
632eaeab | 3041 | unsigned long start, end; |
79f0be8d AK |
3042 | int write_mode = (int)(unsigned long)fsdata; |
3043 | ||
3044 | if (write_mode == FALL_BACK_TO_NONDELALLOC) { | |
3045 | if (ext4_should_order_data(inode)) { | |
3046 | return ext4_ordered_write_end(file, mapping, pos, | |
3047 | len, copied, page, fsdata); | |
3048 | } else if (ext4_should_writeback_data(inode)) { | |
3049 | return ext4_writeback_write_end(file, mapping, pos, | |
3050 | len, copied, page, fsdata); | |
3051 | } else { | |
3052 | BUG(); | |
3053 | } | |
3054 | } | |
632eaeab | 3055 | |
9bffad1e | 3056 | trace_ext4_da_write_end(inode, pos, len, copied); |
632eaeab | 3057 | start = pos & (PAGE_CACHE_SIZE - 1); |
af5bc92d | 3058 | end = start + copied - 1; |
64769240 AT |
3059 | |
3060 | /* | |
3061 | * generic_write_end() will run mark_inode_dirty() if i_size | |
3062 | * changes. So let's piggyback the i_disksize mark_inode_dirty | |
3063 | * into that. | |
3064 | */ | |
3065 | ||
3066 | new_i_size = pos + copied; | |
632eaeab MC |
3067 | if (new_i_size > EXT4_I(inode)->i_disksize) { |
3068 | if (ext4_da_should_update_i_disksize(page, end)) { | |
3069 | down_write(&EXT4_I(inode)->i_data_sem); | |
3070 | if (new_i_size > EXT4_I(inode)->i_disksize) { | |
3071 | /* | |
3072 | * Updating i_disksize when extending file | |
3073 | * without needing block allocation | |
3074 | */ | |
3075 | if (ext4_should_order_data(inode)) | |
3076 | ret = ext4_jbd2_file_inode(handle, | |
3077 | inode); | |
64769240 | 3078 | |
632eaeab MC |
3079 | EXT4_I(inode)->i_disksize = new_i_size; |
3080 | } | |
3081 | up_write(&EXT4_I(inode)->i_data_sem); | |
cf17fea6 AK |
3082 | /* We need to mark inode dirty even if |
3083 | * new_i_size is less that inode->i_size | |
3084 | * bu greater than i_disksize.(hint delalloc) | |
3085 | */ | |
3086 | ext4_mark_inode_dirty(handle, inode); | |
64769240 | 3087 | } |
632eaeab | 3088 | } |
64769240 AT |
3089 | ret2 = generic_write_end(file, mapping, pos, len, copied, |
3090 | page, fsdata); | |
3091 | copied = ret2; | |
3092 | if (ret2 < 0) | |
3093 | ret = ret2; | |
3094 | ret2 = ext4_journal_stop(handle); | |
3095 | if (!ret) | |
3096 | ret = ret2; | |
3097 | ||
3098 | return ret ? ret : copied; | |
3099 | } | |
3100 | ||
3101 | static void ext4_da_invalidatepage(struct page *page, unsigned long offset) | |
3102 | { | |
64769240 AT |
3103 | /* |
3104 | * Drop reserved blocks | |
3105 | */ | |
3106 | BUG_ON(!PageLocked(page)); | |
3107 | if (!page_has_buffers(page)) | |
3108 | goto out; | |
3109 | ||
d2a17637 | 3110 | ext4_da_page_release_reservation(page, offset); |
64769240 AT |
3111 | |
3112 | out: | |
3113 | ext4_invalidatepage(page, offset); | |
3114 | ||
3115 | return; | |
3116 | } | |
3117 | ||
ccd2506b TT |
3118 | /* |
3119 | * Force all delayed allocation blocks to be allocated for a given inode. | |
3120 | */ | |
3121 | int ext4_alloc_da_blocks(struct inode *inode) | |
3122 | { | |
3123 | if (!EXT4_I(inode)->i_reserved_data_blocks && | |
3124 | !EXT4_I(inode)->i_reserved_meta_blocks) | |
3125 | return 0; | |
3126 | ||
3127 | /* | |
3128 | * We do something simple for now. The filemap_flush() will | |
3129 | * also start triggering a write of the data blocks, which is | |
3130 | * not strictly speaking necessary (and for users of | |
3131 | * laptop_mode, not even desirable). However, to do otherwise | |
3132 | * would require replicating code paths in: | |
de9a55b8 | 3133 | * |
ccd2506b TT |
3134 | * ext4_da_writepages() -> |
3135 | * write_cache_pages() ---> (via passed in callback function) | |
3136 | * __mpage_da_writepage() --> | |
3137 | * mpage_add_bh_to_extent() | |
3138 | * mpage_da_map_blocks() | |
3139 | * | |
3140 | * The problem is that write_cache_pages(), located in | |
3141 | * mm/page-writeback.c, marks pages clean in preparation for | |
3142 | * doing I/O, which is not desirable if we're not planning on | |
3143 | * doing I/O at all. | |
3144 | * | |
3145 | * We could call write_cache_pages(), and then redirty all of | |
3146 | * the pages by calling redirty_page_for_writeback() but that | |
3147 | * would be ugly in the extreme. So instead we would need to | |
3148 | * replicate parts of the code in the above functions, | |
3149 | * simplifying them becuase we wouldn't actually intend to | |
3150 | * write out the pages, but rather only collect contiguous | |
3151 | * logical block extents, call the multi-block allocator, and | |
3152 | * then update the buffer heads with the block allocations. | |
de9a55b8 | 3153 | * |
ccd2506b TT |
3154 | * For now, though, we'll cheat by calling filemap_flush(), |
3155 | * which will map the blocks, and start the I/O, but not | |
3156 | * actually wait for the I/O to complete. | |
3157 | */ | |
3158 | return filemap_flush(inode->i_mapping); | |
3159 | } | |
64769240 | 3160 | |
ac27a0ec DK |
3161 | /* |
3162 | * bmap() is special. It gets used by applications such as lilo and by | |
3163 | * the swapper to find the on-disk block of a specific piece of data. | |
3164 | * | |
3165 | * Naturally, this is dangerous if the block concerned is still in the | |
617ba13b | 3166 | * journal. If somebody makes a swapfile on an ext4 data-journaling |
ac27a0ec DK |
3167 | * filesystem and enables swap, then they may get a nasty shock when the |
3168 | * data getting swapped to that swapfile suddenly gets overwritten by | |
3169 | * the original zero's written out previously to the journal and | |
3170 | * awaiting writeback in the kernel's buffer cache. | |
3171 | * | |
3172 | * So, if we see any bmap calls here on a modified, data-journaled file, | |
3173 | * take extra steps to flush any blocks which might be in the cache. | |
3174 | */ | |
617ba13b | 3175 | static sector_t ext4_bmap(struct address_space *mapping, sector_t block) |
ac27a0ec DK |
3176 | { |
3177 | struct inode *inode = mapping->host; | |
3178 | journal_t *journal; | |
3179 | int err; | |
3180 | ||
64769240 AT |
3181 | if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && |
3182 | test_opt(inode->i_sb, DELALLOC)) { | |
3183 | /* | |
3184 | * With delalloc we want to sync the file | |
3185 | * so that we can make sure we allocate | |
3186 | * blocks for file | |
3187 | */ | |
3188 | filemap_write_and_wait(mapping); | |
3189 | } | |
3190 | ||
0390131b | 3191 | if (EXT4_JOURNAL(inode) && EXT4_I(inode)->i_state & EXT4_STATE_JDATA) { |
ac27a0ec DK |
3192 | /* |
3193 | * This is a REALLY heavyweight approach, but the use of | |
3194 | * bmap on dirty files is expected to be extremely rare: | |
3195 | * only if we run lilo or swapon on a freshly made file | |
3196 | * do we expect this to happen. | |
3197 | * | |
3198 | * (bmap requires CAP_SYS_RAWIO so this does not | |
3199 | * represent an unprivileged user DOS attack --- we'd be | |
3200 | * in trouble if mortal users could trigger this path at | |
3201 | * will.) | |
3202 | * | |
617ba13b | 3203 | * NB. EXT4_STATE_JDATA is not set on files other than |
ac27a0ec DK |
3204 | * regular files. If somebody wants to bmap a directory |
3205 | * or symlink and gets confused because the buffer | |
3206 | * hasn't yet been flushed to disk, they deserve | |
3207 | * everything they get. | |
3208 | */ | |
3209 | ||
617ba13b MC |
3210 | EXT4_I(inode)->i_state &= ~EXT4_STATE_JDATA; |
3211 | journal = EXT4_JOURNAL(inode); | |
dab291af MC |
3212 | jbd2_journal_lock_updates(journal); |
3213 | err = jbd2_journal_flush(journal); | |
3214 | jbd2_journal_unlock_updates(journal); | |
ac27a0ec DK |
3215 | |
3216 | if (err) | |
3217 | return 0; | |
3218 | } | |
3219 | ||
af5bc92d | 3220 | return generic_block_bmap(mapping, block, ext4_get_block); |
ac27a0ec DK |
3221 | } |
3222 | ||
617ba13b | 3223 | static int ext4_readpage(struct file *file, struct page *page) |
ac27a0ec | 3224 | { |
617ba13b | 3225 | return mpage_readpage(page, ext4_get_block); |
ac27a0ec DK |
3226 | } |
3227 | ||
3228 | static int | |
617ba13b | 3229 | ext4_readpages(struct file *file, struct address_space *mapping, |
ac27a0ec DK |
3230 | struct list_head *pages, unsigned nr_pages) |
3231 | { | |
617ba13b | 3232 | return mpage_readpages(mapping, pages, nr_pages, ext4_get_block); |
ac27a0ec DK |
3233 | } |
3234 | ||
617ba13b | 3235 | static void ext4_invalidatepage(struct page *page, unsigned long offset) |
ac27a0ec | 3236 | { |
617ba13b | 3237 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
ac27a0ec DK |
3238 | |
3239 | /* | |
3240 | * If it's a full truncate we just forget about the pending dirtying | |
3241 | */ | |
3242 | if (offset == 0) | |
3243 | ClearPageChecked(page); | |
3244 | ||
0390131b FM |
3245 | if (journal) |
3246 | jbd2_journal_invalidatepage(journal, page, offset); | |
3247 | else | |
3248 | block_invalidatepage(page, offset); | |
ac27a0ec DK |
3249 | } |
3250 | ||
617ba13b | 3251 | static int ext4_releasepage(struct page *page, gfp_t wait) |
ac27a0ec | 3252 | { |
617ba13b | 3253 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
ac27a0ec DK |
3254 | |
3255 | WARN_ON(PageChecked(page)); | |
3256 | if (!page_has_buffers(page)) | |
3257 | return 0; | |
0390131b FM |
3258 | if (journal) |
3259 | return jbd2_journal_try_to_free_buffers(journal, page, wait); | |
3260 | else | |
3261 | return try_to_free_buffers(page); | |
ac27a0ec DK |
3262 | } |
3263 | ||
3264 | /* | |
3265 | * If the O_DIRECT write will extend the file then add this inode to the | |
3266 | * orphan list. So recovery will truncate it back to the original size | |
3267 | * if the machine crashes during the write. | |
3268 | * | |
3269 | * If the O_DIRECT write is intantiating holes inside i_size and the machine | |
7fb5409d JK |
3270 | * crashes then stale disk data _may_ be exposed inside the file. But current |
3271 | * VFS code falls back into buffered path in that case so we are safe. | |
ac27a0ec | 3272 | */ |
617ba13b | 3273 | static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb, |
de9a55b8 TT |
3274 | const struct iovec *iov, loff_t offset, |
3275 | unsigned long nr_segs) | |
ac27a0ec DK |
3276 | { |
3277 | struct file *file = iocb->ki_filp; | |
3278 | struct inode *inode = file->f_mapping->host; | |
617ba13b | 3279 | struct ext4_inode_info *ei = EXT4_I(inode); |
7fb5409d | 3280 | handle_t *handle; |
ac27a0ec DK |
3281 | ssize_t ret; |
3282 | int orphan = 0; | |
3283 | size_t count = iov_length(iov, nr_segs); | |
3284 | ||
3285 | if (rw == WRITE) { | |
3286 | loff_t final_size = offset + count; | |
3287 | ||
ac27a0ec | 3288 | if (final_size > inode->i_size) { |
7fb5409d JK |
3289 | /* Credits for sb + inode write */ |
3290 | handle = ext4_journal_start(inode, 2); | |
3291 | if (IS_ERR(handle)) { | |
3292 | ret = PTR_ERR(handle); | |
3293 | goto out; | |
3294 | } | |
617ba13b | 3295 | ret = ext4_orphan_add(handle, inode); |
7fb5409d JK |
3296 | if (ret) { |
3297 | ext4_journal_stop(handle); | |
3298 | goto out; | |
3299 | } | |
ac27a0ec DK |
3300 | orphan = 1; |
3301 | ei->i_disksize = inode->i_size; | |
7fb5409d | 3302 | ext4_journal_stop(handle); |
ac27a0ec DK |
3303 | } |
3304 | } | |
3305 | ||
3306 | ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, | |
3307 | offset, nr_segs, | |
617ba13b | 3308 | ext4_get_block, NULL); |
ac27a0ec | 3309 | |
7fb5409d | 3310 | if (orphan) { |
ac27a0ec DK |
3311 | int err; |
3312 | ||
7fb5409d JK |
3313 | /* Credits for sb + inode write */ |
3314 | handle = ext4_journal_start(inode, 2); | |
3315 | if (IS_ERR(handle)) { | |
3316 | /* This is really bad luck. We've written the data | |
3317 | * but cannot extend i_size. Bail out and pretend | |
3318 | * the write failed... */ | |
3319 | ret = PTR_ERR(handle); | |
3320 | goto out; | |
3321 | } | |
3322 | if (inode->i_nlink) | |
617ba13b | 3323 | ext4_orphan_del(handle, inode); |
7fb5409d | 3324 | if (ret > 0) { |
ac27a0ec DK |
3325 | loff_t end = offset + ret; |
3326 | if (end > inode->i_size) { | |
3327 | ei->i_disksize = end; | |
3328 | i_size_write(inode, end); | |
3329 | /* | |
3330 | * We're going to return a positive `ret' | |
3331 | * here due to non-zero-length I/O, so there's | |
3332 | * no way of reporting error returns from | |
617ba13b | 3333 | * ext4_mark_inode_dirty() to userspace. So |
ac27a0ec DK |
3334 | * ignore it. |
3335 | */ | |
617ba13b | 3336 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
3337 | } |
3338 | } | |
617ba13b | 3339 | err = ext4_journal_stop(handle); |
ac27a0ec DK |
3340 | if (ret == 0) |
3341 | ret = err; | |
3342 | } | |
3343 | out: | |
3344 | return ret; | |
3345 | } | |
3346 | ||
3347 | /* | |
617ba13b | 3348 | * Pages can be marked dirty completely asynchronously from ext4's journalling |
ac27a0ec DK |
3349 | * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do |
3350 | * much here because ->set_page_dirty is called under VFS locks. The page is | |
3351 | * not necessarily locked. | |
3352 | * | |
3353 | * We cannot just dirty the page and leave attached buffers clean, because the | |
3354 | * buffers' dirty state is "definitive". We cannot just set the buffers dirty | |
3355 | * or jbddirty because all the journalling code will explode. | |
3356 | * | |
3357 | * So what we do is to mark the page "pending dirty" and next time writepage | |
3358 | * is called, propagate that into the buffers appropriately. | |
3359 | */ | |
617ba13b | 3360 | static int ext4_journalled_set_page_dirty(struct page *page) |
ac27a0ec DK |
3361 | { |
3362 | SetPageChecked(page); | |
3363 | return __set_page_dirty_nobuffers(page); | |
3364 | } | |
3365 | ||
617ba13b | 3366 | static const struct address_space_operations ext4_ordered_aops = { |
8ab22b9a HH |
3367 | .readpage = ext4_readpage, |
3368 | .readpages = ext4_readpages, | |
43ce1d23 | 3369 | .writepage = ext4_writepage, |
8ab22b9a HH |
3370 | .sync_page = block_sync_page, |
3371 | .write_begin = ext4_write_begin, | |
3372 | .write_end = ext4_ordered_write_end, | |
3373 | .bmap = ext4_bmap, | |
3374 | .invalidatepage = ext4_invalidatepage, | |
3375 | .releasepage = ext4_releasepage, | |
3376 | .direct_IO = ext4_direct_IO, | |
3377 | .migratepage = buffer_migrate_page, | |
3378 | .is_partially_uptodate = block_is_partially_uptodate, | |
ac27a0ec DK |
3379 | }; |
3380 | ||
617ba13b | 3381 | static const struct address_space_operations ext4_writeback_aops = { |
8ab22b9a HH |
3382 | .readpage = ext4_readpage, |
3383 | .readpages = ext4_readpages, | |
43ce1d23 | 3384 | .writepage = ext4_writepage, |
8ab22b9a HH |
3385 | .sync_page = block_sync_page, |
3386 | .write_begin = ext4_write_begin, | |
3387 | .write_end = ext4_writeback_write_end, | |
3388 | .bmap = ext4_bmap, | |
3389 | .invalidatepage = ext4_invalidatepage, | |
3390 | .releasepage = ext4_releasepage, | |
3391 | .direct_IO = ext4_direct_IO, | |
3392 | .migratepage = buffer_migrate_page, | |
3393 | .is_partially_uptodate = block_is_partially_uptodate, | |
ac27a0ec DK |
3394 | }; |
3395 | ||
617ba13b | 3396 | static const struct address_space_operations ext4_journalled_aops = { |
8ab22b9a HH |
3397 | .readpage = ext4_readpage, |
3398 | .readpages = ext4_readpages, | |
43ce1d23 | 3399 | .writepage = ext4_writepage, |
8ab22b9a HH |
3400 | .sync_page = block_sync_page, |
3401 | .write_begin = ext4_write_begin, | |
3402 | .write_end = ext4_journalled_write_end, | |
3403 | .set_page_dirty = ext4_journalled_set_page_dirty, | |
3404 | .bmap = ext4_bmap, | |
3405 | .invalidatepage = ext4_invalidatepage, | |
3406 | .releasepage = ext4_releasepage, | |
3407 | .is_partially_uptodate = block_is_partially_uptodate, | |
ac27a0ec DK |
3408 | }; |
3409 | ||
64769240 | 3410 | static const struct address_space_operations ext4_da_aops = { |
8ab22b9a HH |
3411 | .readpage = ext4_readpage, |
3412 | .readpages = ext4_readpages, | |
43ce1d23 | 3413 | .writepage = ext4_writepage, |
8ab22b9a HH |
3414 | .writepages = ext4_da_writepages, |
3415 | .sync_page = block_sync_page, | |
3416 | .write_begin = ext4_da_write_begin, | |
3417 | .write_end = ext4_da_write_end, | |
3418 | .bmap = ext4_bmap, | |
3419 | .invalidatepage = ext4_da_invalidatepage, | |
3420 | .releasepage = ext4_releasepage, | |
3421 | .direct_IO = ext4_direct_IO, | |
3422 | .migratepage = buffer_migrate_page, | |
3423 | .is_partially_uptodate = block_is_partially_uptodate, | |
64769240 AT |
3424 | }; |
3425 | ||
617ba13b | 3426 | void ext4_set_aops(struct inode *inode) |
ac27a0ec | 3427 | { |
cd1aac32 AK |
3428 | if (ext4_should_order_data(inode) && |
3429 | test_opt(inode->i_sb, DELALLOC)) | |
3430 | inode->i_mapping->a_ops = &ext4_da_aops; | |
3431 | else if (ext4_should_order_data(inode)) | |
617ba13b | 3432 | inode->i_mapping->a_ops = &ext4_ordered_aops; |
64769240 AT |
3433 | else if (ext4_should_writeback_data(inode) && |
3434 | test_opt(inode->i_sb, DELALLOC)) | |
3435 | inode->i_mapping->a_ops = &ext4_da_aops; | |
617ba13b MC |
3436 | else if (ext4_should_writeback_data(inode)) |
3437 | inode->i_mapping->a_ops = &ext4_writeback_aops; | |
ac27a0ec | 3438 | else |
617ba13b | 3439 | inode->i_mapping->a_ops = &ext4_journalled_aops; |
ac27a0ec DK |
3440 | } |
3441 | ||
3442 | /* | |
617ba13b | 3443 | * ext4_block_truncate_page() zeroes out a mapping from file offset `from' |
ac27a0ec DK |
3444 | * up to the end of the block which corresponds to `from'. |
3445 | * This required during truncate. We need to physically zero the tail end | |
3446 | * of that block so it doesn't yield old data if the file is later grown. | |
3447 | */ | |
cf108bca | 3448 | int ext4_block_truncate_page(handle_t *handle, |
ac27a0ec DK |
3449 | struct address_space *mapping, loff_t from) |
3450 | { | |
617ba13b | 3451 | ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT; |
ac27a0ec | 3452 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
725d26d3 AK |
3453 | unsigned blocksize, length, pos; |
3454 | ext4_lblk_t iblock; | |
ac27a0ec DK |
3455 | struct inode *inode = mapping->host; |
3456 | struct buffer_head *bh; | |
cf108bca | 3457 | struct page *page; |
ac27a0ec | 3458 | int err = 0; |
ac27a0ec | 3459 | |
f4a01017 TT |
3460 | page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT, |
3461 | mapping_gfp_mask(mapping) & ~__GFP_FS); | |
cf108bca JK |
3462 | if (!page) |
3463 | return -EINVAL; | |
3464 | ||
ac27a0ec DK |
3465 | blocksize = inode->i_sb->s_blocksize; |
3466 | length = blocksize - (offset & (blocksize - 1)); | |
3467 | iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
3468 | ||
3469 | /* | |
3470 | * For "nobh" option, we can only work if we don't need to | |
3471 | * read-in the page - otherwise we create buffers to do the IO. | |
3472 | */ | |
3473 | if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && | |
617ba13b | 3474 | ext4_should_writeback_data(inode) && PageUptodate(page)) { |
eebd2aa3 | 3475 | zero_user(page, offset, length); |
ac27a0ec DK |
3476 | set_page_dirty(page); |
3477 | goto unlock; | |
3478 | } | |
3479 | ||
3480 | if (!page_has_buffers(page)) | |
3481 | create_empty_buffers(page, blocksize, 0); | |
3482 | ||
3483 | /* Find the buffer that contains "offset" */ | |
3484 | bh = page_buffers(page); | |
3485 | pos = blocksize; | |
3486 | while (offset >= pos) { | |
3487 | bh = bh->b_this_page; | |
3488 | iblock++; | |
3489 | pos += blocksize; | |
3490 | } | |
3491 | ||
3492 | err = 0; | |
3493 | if (buffer_freed(bh)) { | |
3494 | BUFFER_TRACE(bh, "freed: skip"); | |
3495 | goto unlock; | |
3496 | } | |
3497 | ||
3498 | if (!buffer_mapped(bh)) { | |
3499 | BUFFER_TRACE(bh, "unmapped"); | |
617ba13b | 3500 | ext4_get_block(inode, iblock, bh, 0); |
ac27a0ec DK |
3501 | /* unmapped? It's a hole - nothing to do */ |
3502 | if (!buffer_mapped(bh)) { | |
3503 | BUFFER_TRACE(bh, "still unmapped"); | |
3504 | goto unlock; | |
3505 | } | |
3506 | } | |
3507 | ||
3508 | /* Ok, it's mapped. Make sure it's up-to-date */ | |
3509 | if (PageUptodate(page)) | |
3510 | set_buffer_uptodate(bh); | |
3511 | ||
3512 | if (!buffer_uptodate(bh)) { | |
3513 | err = -EIO; | |
3514 | ll_rw_block(READ, 1, &bh); | |
3515 | wait_on_buffer(bh); | |
3516 | /* Uhhuh. Read error. Complain and punt. */ | |
3517 | if (!buffer_uptodate(bh)) | |
3518 | goto unlock; | |
3519 | } | |
3520 | ||
617ba13b | 3521 | if (ext4_should_journal_data(inode)) { |
ac27a0ec | 3522 | BUFFER_TRACE(bh, "get write access"); |
617ba13b | 3523 | err = ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
3524 | if (err) |
3525 | goto unlock; | |
3526 | } | |
3527 | ||
eebd2aa3 | 3528 | zero_user(page, offset, length); |
ac27a0ec DK |
3529 | |
3530 | BUFFER_TRACE(bh, "zeroed end of block"); | |
3531 | ||
3532 | err = 0; | |
617ba13b | 3533 | if (ext4_should_journal_data(inode)) { |
0390131b | 3534 | err = ext4_handle_dirty_metadata(handle, inode, bh); |
ac27a0ec | 3535 | } else { |
617ba13b | 3536 | if (ext4_should_order_data(inode)) |
678aaf48 | 3537 | err = ext4_jbd2_file_inode(handle, inode); |
ac27a0ec DK |
3538 | mark_buffer_dirty(bh); |
3539 | } | |
3540 | ||
3541 | unlock: | |
3542 | unlock_page(page); | |
3543 | page_cache_release(page); | |
3544 | return err; | |
3545 | } | |
3546 | ||
3547 | /* | |
3548 | * Probably it should be a library function... search for first non-zero word | |
3549 | * or memcmp with zero_page, whatever is better for particular architecture. | |
3550 | * Linus? | |
3551 | */ | |
3552 | static inline int all_zeroes(__le32 *p, __le32 *q) | |
3553 | { | |
3554 | while (p < q) | |
3555 | if (*p++) | |
3556 | return 0; | |
3557 | return 1; | |
3558 | } | |
3559 | ||
3560 | /** | |
617ba13b | 3561 | * ext4_find_shared - find the indirect blocks for partial truncation. |
ac27a0ec DK |
3562 | * @inode: inode in question |
3563 | * @depth: depth of the affected branch | |
617ba13b | 3564 | * @offsets: offsets of pointers in that branch (see ext4_block_to_path) |
ac27a0ec DK |
3565 | * @chain: place to store the pointers to partial indirect blocks |
3566 | * @top: place to the (detached) top of branch | |
3567 | * | |
617ba13b | 3568 | * This is a helper function used by ext4_truncate(). |
ac27a0ec DK |
3569 | * |
3570 | * When we do truncate() we may have to clean the ends of several | |
3571 | * indirect blocks but leave the blocks themselves alive. Block is | |
3572 | * partially truncated if some data below the new i_size is refered | |
3573 | * from it (and it is on the path to the first completely truncated | |
3574 | * data block, indeed). We have to free the top of that path along | |
3575 | * with everything to the right of the path. Since no allocation | |
617ba13b | 3576 | * past the truncation point is possible until ext4_truncate() |
ac27a0ec DK |
3577 | * finishes, we may safely do the latter, but top of branch may |
3578 | * require special attention - pageout below the truncation point | |
3579 | * might try to populate it. | |
3580 | * | |
3581 | * We atomically detach the top of branch from the tree, store the | |
3582 | * block number of its root in *@top, pointers to buffer_heads of | |
3583 | * partially truncated blocks - in @chain[].bh and pointers to | |
3584 | * their last elements that should not be removed - in | |
3585 | * @chain[].p. Return value is the pointer to last filled element | |
3586 | * of @chain. | |
3587 | * | |
3588 | * The work left to caller to do the actual freeing of subtrees: | |
3589 | * a) free the subtree starting from *@top | |
3590 | * b) free the subtrees whose roots are stored in | |
3591 | * (@chain[i].p+1 .. end of @chain[i].bh->b_data) | |
3592 | * c) free the subtrees growing from the inode past the @chain[0]. | |
3593 | * (no partially truncated stuff there). */ | |
3594 | ||
617ba13b | 3595 | static Indirect *ext4_find_shared(struct inode *inode, int depth, |
de9a55b8 TT |
3596 | ext4_lblk_t offsets[4], Indirect chain[4], |
3597 | __le32 *top) | |
ac27a0ec DK |
3598 | { |
3599 | Indirect *partial, *p; | |
3600 | int k, err; | |
3601 | ||
3602 | *top = 0; | |
3603 | /* Make k index the deepest non-null offest + 1 */ | |
3604 | for (k = depth; k > 1 && !offsets[k-1]; k--) | |
3605 | ; | |
617ba13b | 3606 | partial = ext4_get_branch(inode, k, offsets, chain, &err); |
ac27a0ec DK |
3607 | /* Writer: pointers */ |
3608 | if (!partial) | |
3609 | partial = chain + k-1; | |
3610 | /* | |
3611 | * If the branch acquired continuation since we've looked at it - | |
3612 | * fine, it should all survive and (new) top doesn't belong to us. | |
3613 | */ | |
3614 | if (!partial->key && *partial->p) | |
3615 | /* Writer: end */ | |
3616 | goto no_top; | |
af5bc92d | 3617 | for (p = partial; (p > chain) && all_zeroes((__le32 *) p->bh->b_data, p->p); p--) |
ac27a0ec DK |
3618 | ; |
3619 | /* | |
3620 | * OK, we've found the last block that must survive. The rest of our | |
3621 | * branch should be detached before unlocking. However, if that rest | |
3622 | * of branch is all ours and does not grow immediately from the inode | |
3623 | * it's easier to cheat and just decrement partial->p. | |
3624 | */ | |
3625 | if (p == chain + k - 1 && p > chain) { | |
3626 | p->p--; | |
3627 | } else { | |
3628 | *top = *p->p; | |
617ba13b | 3629 | /* Nope, don't do this in ext4. Must leave the tree intact */ |
ac27a0ec DK |
3630 | #if 0 |
3631 | *p->p = 0; | |
3632 | #endif | |
3633 | } | |
3634 | /* Writer: end */ | |
3635 | ||
af5bc92d | 3636 | while (partial > p) { |
ac27a0ec DK |
3637 | brelse(partial->bh); |
3638 | partial--; | |
3639 | } | |
3640 | no_top: | |
3641 | return partial; | |
3642 | } | |
3643 | ||
3644 | /* | |
3645 | * Zero a number of block pointers in either an inode or an indirect block. | |
3646 | * If we restart the transaction we must again get write access to the | |
3647 | * indirect block for further modification. | |
3648 | * | |
3649 | * We release `count' blocks on disk, but (last - first) may be greater | |
3650 | * than `count' because there can be holes in there. | |
3651 | */ | |
617ba13b | 3652 | static void ext4_clear_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
3653 | struct buffer_head *bh, |
3654 | ext4_fsblk_t block_to_free, | |
3655 | unsigned long count, __le32 *first, | |
3656 | __le32 *last) | |
ac27a0ec DK |
3657 | { |
3658 | __le32 *p; | |
3659 | if (try_to_extend_transaction(handle, inode)) { | |
3660 | if (bh) { | |
0390131b FM |
3661 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
3662 | ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec | 3663 | } |
617ba13b | 3664 | ext4_mark_inode_dirty(handle, inode); |
487caeef JK |
3665 | ext4_truncate_restart_trans(handle, inode, |
3666 | blocks_for_truncate(inode)); | |
ac27a0ec DK |
3667 | if (bh) { |
3668 | BUFFER_TRACE(bh, "retaking write access"); | |
617ba13b | 3669 | ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
3670 | } |
3671 | } | |
3672 | ||
3673 | /* | |
de9a55b8 TT |
3674 | * Any buffers which are on the journal will be in memory. We |
3675 | * find them on the hash table so jbd2_journal_revoke() will | |
3676 | * run jbd2_journal_forget() on them. We've already detached | |
3677 | * each block from the file, so bforget() in | |
3678 | * jbd2_journal_forget() should be safe. | |
ac27a0ec | 3679 | * |
dab291af | 3680 | * AKPM: turn on bforget in jbd2_journal_forget()!!! |
ac27a0ec DK |
3681 | */ |
3682 | for (p = first; p < last; p++) { | |
3683 | u32 nr = le32_to_cpu(*p); | |
3684 | if (nr) { | |
1d03ec98 | 3685 | struct buffer_head *tbh; |
ac27a0ec DK |
3686 | |
3687 | *p = 0; | |
1d03ec98 AK |
3688 | tbh = sb_find_get_block(inode->i_sb, nr); |
3689 | ext4_forget(handle, 0, inode, tbh, nr); | |
ac27a0ec DK |
3690 | } |
3691 | } | |
3692 | ||
c9de560d | 3693 | ext4_free_blocks(handle, inode, block_to_free, count, 0); |
ac27a0ec DK |
3694 | } |
3695 | ||
3696 | /** | |
617ba13b | 3697 | * ext4_free_data - free a list of data blocks |
ac27a0ec DK |
3698 | * @handle: handle for this transaction |
3699 | * @inode: inode we are dealing with | |
3700 | * @this_bh: indirect buffer_head which contains *@first and *@last | |
3701 | * @first: array of block numbers | |
3702 | * @last: points immediately past the end of array | |
3703 | * | |
3704 | * We are freeing all blocks refered from that array (numbers are stored as | |
3705 | * little-endian 32-bit) and updating @inode->i_blocks appropriately. | |
3706 | * | |
3707 | * We accumulate contiguous runs of blocks to free. Conveniently, if these | |
3708 | * blocks are contiguous then releasing them at one time will only affect one | |
3709 | * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't | |
3710 | * actually use a lot of journal space. | |
3711 | * | |
3712 | * @this_bh will be %NULL if @first and @last point into the inode's direct | |
3713 | * block pointers. | |
3714 | */ | |
617ba13b | 3715 | static void ext4_free_data(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
3716 | struct buffer_head *this_bh, |
3717 | __le32 *first, __le32 *last) | |
3718 | { | |
617ba13b | 3719 | ext4_fsblk_t block_to_free = 0; /* Starting block # of a run */ |
ac27a0ec DK |
3720 | unsigned long count = 0; /* Number of blocks in the run */ |
3721 | __le32 *block_to_free_p = NULL; /* Pointer into inode/ind | |
3722 | corresponding to | |
3723 | block_to_free */ | |
617ba13b | 3724 | ext4_fsblk_t nr; /* Current block # */ |
ac27a0ec DK |
3725 | __le32 *p; /* Pointer into inode/ind |
3726 | for current block */ | |
3727 | int err; | |
3728 | ||
3729 | if (this_bh) { /* For indirect block */ | |
3730 | BUFFER_TRACE(this_bh, "get_write_access"); | |
617ba13b | 3731 | err = ext4_journal_get_write_access(handle, this_bh); |
ac27a0ec DK |
3732 | /* Important: if we can't update the indirect pointers |
3733 | * to the blocks, we can't free them. */ | |
3734 | if (err) | |
3735 | return; | |
3736 | } | |
3737 | ||
3738 | for (p = first; p < last; p++) { | |
3739 | nr = le32_to_cpu(*p); | |
3740 | if (nr) { | |
3741 | /* accumulate blocks to free if they're contiguous */ | |
3742 | if (count == 0) { | |
3743 | block_to_free = nr; | |
3744 | block_to_free_p = p; | |
3745 | count = 1; | |
3746 | } else if (nr == block_to_free + count) { | |
3747 | count++; | |
3748 | } else { | |
617ba13b | 3749 | ext4_clear_blocks(handle, inode, this_bh, |
ac27a0ec DK |
3750 | block_to_free, |
3751 | count, block_to_free_p, p); | |
3752 | block_to_free = nr; | |
3753 | block_to_free_p = p; | |
3754 | count = 1; | |
3755 | } | |
3756 | } | |
3757 | } | |
3758 | ||
3759 | if (count > 0) | |
617ba13b | 3760 | ext4_clear_blocks(handle, inode, this_bh, block_to_free, |
ac27a0ec DK |
3761 | count, block_to_free_p, p); |
3762 | ||
3763 | if (this_bh) { | |
0390131b | 3764 | BUFFER_TRACE(this_bh, "call ext4_handle_dirty_metadata"); |
71dc8fbc DG |
3765 | |
3766 | /* | |
3767 | * The buffer head should have an attached journal head at this | |
3768 | * point. However, if the data is corrupted and an indirect | |
3769 | * block pointed to itself, it would have been detached when | |
3770 | * the block was cleared. Check for this instead of OOPSing. | |
3771 | */ | |
e7f07968 | 3772 | if ((EXT4_JOURNAL(inode) == NULL) || bh2jh(this_bh)) |
0390131b | 3773 | ext4_handle_dirty_metadata(handle, inode, this_bh); |
71dc8fbc DG |
3774 | else |
3775 | ext4_error(inode->i_sb, __func__, | |
3776 | "circular indirect block detected, " | |
3777 | "inode=%lu, block=%llu", | |
3778 | inode->i_ino, | |
3779 | (unsigned long long) this_bh->b_blocknr); | |
ac27a0ec DK |
3780 | } |
3781 | } | |
3782 | ||
3783 | /** | |
617ba13b | 3784 | * ext4_free_branches - free an array of branches |
ac27a0ec DK |
3785 | * @handle: JBD handle for this transaction |
3786 | * @inode: inode we are dealing with | |
3787 | * @parent_bh: the buffer_head which contains *@first and *@last | |
3788 | * @first: array of block numbers | |
3789 | * @last: pointer immediately past the end of array | |
3790 | * @depth: depth of the branches to free | |
3791 | * | |
3792 | * We are freeing all blocks refered from these branches (numbers are | |
3793 | * stored as little-endian 32-bit) and updating @inode->i_blocks | |
3794 | * appropriately. | |
3795 | */ | |
617ba13b | 3796 | static void ext4_free_branches(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
3797 | struct buffer_head *parent_bh, |
3798 | __le32 *first, __le32 *last, int depth) | |
3799 | { | |
617ba13b | 3800 | ext4_fsblk_t nr; |
ac27a0ec DK |
3801 | __le32 *p; |
3802 | ||
0390131b | 3803 | if (ext4_handle_is_aborted(handle)) |
ac27a0ec DK |
3804 | return; |
3805 | ||
3806 | if (depth--) { | |
3807 | struct buffer_head *bh; | |
617ba13b | 3808 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
ac27a0ec DK |
3809 | p = last; |
3810 | while (--p >= first) { | |
3811 | nr = le32_to_cpu(*p); | |
3812 | if (!nr) | |
3813 | continue; /* A hole */ | |
3814 | ||
3815 | /* Go read the buffer for the next level down */ | |
3816 | bh = sb_bread(inode->i_sb, nr); | |
3817 | ||
3818 | /* | |
3819 | * A read failure? Report error and clear slot | |
3820 | * (should be rare). | |
3821 | */ | |
3822 | if (!bh) { | |
617ba13b | 3823 | ext4_error(inode->i_sb, "ext4_free_branches", |
2ae02107 | 3824 | "Read failure, inode=%lu, block=%llu", |
ac27a0ec DK |
3825 | inode->i_ino, nr); |
3826 | continue; | |
3827 | } | |
3828 | ||
3829 | /* This zaps the entire block. Bottom up. */ | |
3830 | BUFFER_TRACE(bh, "free child branches"); | |
617ba13b | 3831 | ext4_free_branches(handle, inode, bh, |
af5bc92d TT |
3832 | (__le32 *) bh->b_data, |
3833 | (__le32 *) bh->b_data + addr_per_block, | |
3834 | depth); | |
ac27a0ec DK |
3835 | |
3836 | /* | |
3837 | * We've probably journalled the indirect block several | |
3838 | * times during the truncate. But it's no longer | |
3839 | * needed and we now drop it from the transaction via | |
dab291af | 3840 | * jbd2_journal_revoke(). |
ac27a0ec DK |
3841 | * |
3842 | * That's easy if it's exclusively part of this | |
3843 | * transaction. But if it's part of the committing | |
dab291af | 3844 | * transaction then jbd2_journal_forget() will simply |
ac27a0ec | 3845 | * brelse() it. That means that if the underlying |
617ba13b | 3846 | * block is reallocated in ext4_get_block(), |
ac27a0ec DK |
3847 | * unmap_underlying_metadata() will find this block |
3848 | * and will try to get rid of it. damn, damn. | |
3849 | * | |
3850 | * If this block has already been committed to the | |
3851 | * journal, a revoke record will be written. And | |
3852 | * revoke records must be emitted *before* clearing | |
3853 | * this block's bit in the bitmaps. | |
3854 | */ | |
617ba13b | 3855 | ext4_forget(handle, 1, inode, bh, bh->b_blocknr); |
ac27a0ec DK |
3856 | |
3857 | /* | |
3858 | * Everything below this this pointer has been | |
3859 | * released. Now let this top-of-subtree go. | |
3860 | * | |
3861 | * We want the freeing of this indirect block to be | |
3862 | * atomic in the journal with the updating of the | |
3863 | * bitmap block which owns it. So make some room in | |
3864 | * the journal. | |
3865 | * | |
3866 | * We zero the parent pointer *after* freeing its | |
3867 | * pointee in the bitmaps, so if extend_transaction() | |
3868 | * for some reason fails to put the bitmap changes and | |
3869 | * the release into the same transaction, recovery | |
3870 | * will merely complain about releasing a free block, | |
3871 | * rather than leaking blocks. | |
3872 | */ | |
0390131b | 3873 | if (ext4_handle_is_aborted(handle)) |
ac27a0ec DK |
3874 | return; |
3875 | if (try_to_extend_transaction(handle, inode)) { | |
617ba13b | 3876 | ext4_mark_inode_dirty(handle, inode); |
487caeef JK |
3877 | ext4_truncate_restart_trans(handle, inode, |
3878 | blocks_for_truncate(inode)); | |
ac27a0ec DK |
3879 | } |
3880 | ||
c9de560d | 3881 | ext4_free_blocks(handle, inode, nr, 1, 1); |
ac27a0ec DK |
3882 | |
3883 | if (parent_bh) { | |
3884 | /* | |
3885 | * The block which we have just freed is | |
3886 | * pointed to by an indirect block: journal it | |
3887 | */ | |
3888 | BUFFER_TRACE(parent_bh, "get_write_access"); | |
617ba13b | 3889 | if (!ext4_journal_get_write_access(handle, |
ac27a0ec DK |
3890 | parent_bh)){ |
3891 | *p = 0; | |
3892 | BUFFER_TRACE(parent_bh, | |
0390131b FM |
3893 | "call ext4_handle_dirty_metadata"); |
3894 | ext4_handle_dirty_metadata(handle, | |
3895 | inode, | |
3896 | parent_bh); | |
ac27a0ec DK |
3897 | } |
3898 | } | |
3899 | } | |
3900 | } else { | |
3901 | /* We have reached the bottom of the tree. */ | |
3902 | BUFFER_TRACE(parent_bh, "free data blocks"); | |
617ba13b | 3903 | ext4_free_data(handle, inode, parent_bh, first, last); |
ac27a0ec DK |
3904 | } |
3905 | } | |
3906 | ||
91ef4caf DG |
3907 | int ext4_can_truncate(struct inode *inode) |
3908 | { | |
3909 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | |
3910 | return 0; | |
3911 | if (S_ISREG(inode->i_mode)) | |
3912 | return 1; | |
3913 | if (S_ISDIR(inode->i_mode)) | |
3914 | return 1; | |
3915 | if (S_ISLNK(inode->i_mode)) | |
3916 | return !ext4_inode_is_fast_symlink(inode); | |
3917 | return 0; | |
3918 | } | |
3919 | ||
ac27a0ec | 3920 | /* |
617ba13b | 3921 | * ext4_truncate() |
ac27a0ec | 3922 | * |
617ba13b MC |
3923 | * We block out ext4_get_block() block instantiations across the entire |
3924 | * transaction, and VFS/VM ensures that ext4_truncate() cannot run | |
ac27a0ec DK |
3925 | * simultaneously on behalf of the same inode. |
3926 | * | |
3927 | * As we work through the truncate and commmit bits of it to the journal there | |
3928 | * is one core, guiding principle: the file's tree must always be consistent on | |
3929 | * disk. We must be able to restart the truncate after a crash. | |
3930 | * | |
3931 | * The file's tree may be transiently inconsistent in memory (although it | |
3932 | * probably isn't), but whenever we close off and commit a journal transaction, | |
3933 | * the contents of (the filesystem + the journal) must be consistent and | |
3934 | * restartable. It's pretty simple, really: bottom up, right to left (although | |
3935 | * left-to-right works OK too). | |
3936 | * | |
3937 | * Note that at recovery time, journal replay occurs *before* the restart of | |
3938 | * truncate against the orphan inode list. | |
3939 | * | |
3940 | * The committed inode has the new, desired i_size (which is the same as | |
617ba13b | 3941 | * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see |
ac27a0ec | 3942 | * that this inode's truncate did not complete and it will again call |
617ba13b MC |
3943 | * ext4_truncate() to have another go. So there will be instantiated blocks |
3944 | * to the right of the truncation point in a crashed ext4 filesystem. But | |
ac27a0ec | 3945 | * that's fine - as long as they are linked from the inode, the post-crash |
617ba13b | 3946 | * ext4_truncate() run will find them and release them. |
ac27a0ec | 3947 | */ |
617ba13b | 3948 | void ext4_truncate(struct inode *inode) |
ac27a0ec DK |
3949 | { |
3950 | handle_t *handle; | |
617ba13b | 3951 | struct ext4_inode_info *ei = EXT4_I(inode); |
ac27a0ec | 3952 | __le32 *i_data = ei->i_data; |
617ba13b | 3953 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
ac27a0ec | 3954 | struct address_space *mapping = inode->i_mapping; |
725d26d3 | 3955 | ext4_lblk_t offsets[4]; |
ac27a0ec DK |
3956 | Indirect chain[4]; |
3957 | Indirect *partial; | |
3958 | __le32 nr = 0; | |
3959 | int n; | |
725d26d3 | 3960 | ext4_lblk_t last_block; |
ac27a0ec | 3961 | unsigned blocksize = inode->i_sb->s_blocksize; |
ac27a0ec | 3962 | |
91ef4caf | 3963 | if (!ext4_can_truncate(inode)) |
ac27a0ec DK |
3964 | return; |
3965 | ||
0eab9282 TT |
3966 | if (ei->i_disksize && inode->i_size == 0 && |
3967 | !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC)) | |
7d8f9f7d TT |
3968 | ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE; |
3969 | ||
1d03ec98 | 3970 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
cf108bca | 3971 | ext4_ext_truncate(inode); |
1d03ec98 AK |
3972 | return; |
3973 | } | |
a86c6181 | 3974 | |
ac27a0ec | 3975 | handle = start_transaction(inode); |
cf108bca | 3976 | if (IS_ERR(handle)) |
ac27a0ec | 3977 | return; /* AKPM: return what? */ |
ac27a0ec DK |
3978 | |
3979 | last_block = (inode->i_size + blocksize-1) | |
617ba13b | 3980 | >> EXT4_BLOCK_SIZE_BITS(inode->i_sb); |
ac27a0ec | 3981 | |
cf108bca JK |
3982 | if (inode->i_size & (blocksize - 1)) |
3983 | if (ext4_block_truncate_page(handle, mapping, inode->i_size)) | |
3984 | goto out_stop; | |
ac27a0ec | 3985 | |
617ba13b | 3986 | n = ext4_block_to_path(inode, last_block, offsets, NULL); |
ac27a0ec DK |
3987 | if (n == 0) |
3988 | goto out_stop; /* error */ | |
3989 | ||
3990 | /* | |
3991 | * OK. This truncate is going to happen. We add the inode to the | |
3992 | * orphan list, so that if this truncate spans multiple transactions, | |
3993 | * and we crash, we will resume the truncate when the filesystem | |
3994 | * recovers. It also marks the inode dirty, to catch the new size. | |
3995 | * | |
3996 | * Implication: the file must always be in a sane, consistent | |
3997 | * truncatable state while each transaction commits. | |
3998 | */ | |
617ba13b | 3999 | if (ext4_orphan_add(handle, inode)) |
ac27a0ec DK |
4000 | goto out_stop; |
4001 | ||
632eaeab MC |
4002 | /* |
4003 | * From here we block out all ext4_get_block() callers who want to | |
4004 | * modify the block allocation tree. | |
4005 | */ | |
4006 | down_write(&ei->i_data_sem); | |
b4df2030 | 4007 | |
c2ea3fde | 4008 | ext4_discard_preallocations(inode); |
b4df2030 | 4009 | |
ac27a0ec DK |
4010 | /* |
4011 | * The orphan list entry will now protect us from any crash which | |
4012 | * occurs before the truncate completes, so it is now safe to propagate | |
4013 | * the new, shorter inode size (held for now in i_size) into the | |
4014 | * on-disk inode. We do this via i_disksize, which is the value which | |
617ba13b | 4015 | * ext4 *really* writes onto the disk inode. |
ac27a0ec DK |
4016 | */ |
4017 | ei->i_disksize = inode->i_size; | |
4018 | ||
ac27a0ec | 4019 | if (n == 1) { /* direct blocks */ |
617ba13b MC |
4020 | ext4_free_data(handle, inode, NULL, i_data+offsets[0], |
4021 | i_data + EXT4_NDIR_BLOCKS); | |
ac27a0ec DK |
4022 | goto do_indirects; |
4023 | } | |
4024 | ||
617ba13b | 4025 | partial = ext4_find_shared(inode, n, offsets, chain, &nr); |
ac27a0ec DK |
4026 | /* Kill the top of shared branch (not detached) */ |
4027 | if (nr) { | |
4028 | if (partial == chain) { | |
4029 | /* Shared branch grows from the inode */ | |
617ba13b | 4030 | ext4_free_branches(handle, inode, NULL, |
ac27a0ec DK |
4031 | &nr, &nr+1, (chain+n-1) - partial); |
4032 | *partial->p = 0; | |
4033 | /* | |
4034 | * We mark the inode dirty prior to restart, | |
4035 | * and prior to stop. No need for it here. | |
4036 | */ | |
4037 | } else { | |
4038 | /* Shared branch grows from an indirect block */ | |
4039 | BUFFER_TRACE(partial->bh, "get_write_access"); | |
617ba13b | 4040 | ext4_free_branches(handle, inode, partial->bh, |
ac27a0ec DK |
4041 | partial->p, |
4042 | partial->p+1, (chain+n-1) - partial); | |
4043 | } | |
4044 | } | |
4045 | /* Clear the ends of indirect blocks on the shared branch */ | |
4046 | while (partial > chain) { | |
617ba13b | 4047 | ext4_free_branches(handle, inode, partial->bh, partial->p + 1, |
ac27a0ec DK |
4048 | (__le32*)partial->bh->b_data+addr_per_block, |
4049 | (chain+n-1) - partial); | |
4050 | BUFFER_TRACE(partial->bh, "call brelse"); | |
de9a55b8 | 4051 | brelse(partial->bh); |
ac27a0ec DK |
4052 | partial--; |
4053 | } | |
4054 | do_indirects: | |
4055 | /* Kill the remaining (whole) subtrees */ | |
4056 | switch (offsets[0]) { | |
4057 | default: | |
617ba13b | 4058 | nr = i_data[EXT4_IND_BLOCK]; |
ac27a0ec | 4059 | if (nr) { |
617ba13b MC |
4060 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); |
4061 | i_data[EXT4_IND_BLOCK] = 0; | |
ac27a0ec | 4062 | } |
617ba13b MC |
4063 | case EXT4_IND_BLOCK: |
4064 | nr = i_data[EXT4_DIND_BLOCK]; | |
ac27a0ec | 4065 | if (nr) { |
617ba13b MC |
4066 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); |
4067 | i_data[EXT4_DIND_BLOCK] = 0; | |
ac27a0ec | 4068 | } |
617ba13b MC |
4069 | case EXT4_DIND_BLOCK: |
4070 | nr = i_data[EXT4_TIND_BLOCK]; | |
ac27a0ec | 4071 | if (nr) { |
617ba13b MC |
4072 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); |
4073 | i_data[EXT4_TIND_BLOCK] = 0; | |
ac27a0ec | 4074 | } |
617ba13b | 4075 | case EXT4_TIND_BLOCK: |
ac27a0ec DK |
4076 | ; |
4077 | } | |
4078 | ||
0e855ac8 | 4079 | up_write(&ei->i_data_sem); |
ef7f3835 | 4080 | inode->i_mtime = inode->i_ctime = ext4_current_time(inode); |
617ba13b | 4081 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
4082 | |
4083 | /* | |
4084 | * In a multi-transaction truncate, we only make the final transaction | |
4085 | * synchronous | |
4086 | */ | |
4087 | if (IS_SYNC(inode)) | |
0390131b | 4088 | ext4_handle_sync(handle); |
ac27a0ec DK |
4089 | out_stop: |
4090 | /* | |
4091 | * If this was a simple ftruncate(), and the file will remain alive | |
4092 | * then we need to clear up the orphan record which we created above. | |
4093 | * However, if this was a real unlink then we were called by | |
617ba13b | 4094 | * ext4_delete_inode(), and we allow that function to clean up the |
ac27a0ec DK |
4095 | * orphan info for us. |
4096 | */ | |
4097 | if (inode->i_nlink) | |
617ba13b | 4098 | ext4_orphan_del(handle, inode); |
ac27a0ec | 4099 | |
617ba13b | 4100 | ext4_journal_stop(handle); |
ac27a0ec DK |
4101 | } |
4102 | ||
ac27a0ec | 4103 | /* |
617ba13b | 4104 | * ext4_get_inode_loc returns with an extra refcount against the inode's |
ac27a0ec DK |
4105 | * underlying buffer_head on success. If 'in_mem' is true, we have all |
4106 | * data in memory that is needed to recreate the on-disk version of this | |
4107 | * inode. | |
4108 | */ | |
617ba13b MC |
4109 | static int __ext4_get_inode_loc(struct inode *inode, |
4110 | struct ext4_iloc *iloc, int in_mem) | |
ac27a0ec | 4111 | { |
240799cd TT |
4112 | struct ext4_group_desc *gdp; |
4113 | struct buffer_head *bh; | |
4114 | struct super_block *sb = inode->i_sb; | |
4115 | ext4_fsblk_t block; | |
4116 | int inodes_per_block, inode_offset; | |
4117 | ||
3a06d778 | 4118 | iloc->bh = NULL; |
240799cd TT |
4119 | if (!ext4_valid_inum(sb, inode->i_ino)) |
4120 | return -EIO; | |
ac27a0ec | 4121 | |
240799cd TT |
4122 | iloc->block_group = (inode->i_ino - 1) / EXT4_INODES_PER_GROUP(sb); |
4123 | gdp = ext4_get_group_desc(sb, iloc->block_group, NULL); | |
4124 | if (!gdp) | |
ac27a0ec DK |
4125 | return -EIO; |
4126 | ||
240799cd TT |
4127 | /* |
4128 | * Figure out the offset within the block group inode table | |
4129 | */ | |
4130 | inodes_per_block = (EXT4_BLOCK_SIZE(sb) / EXT4_INODE_SIZE(sb)); | |
4131 | inode_offset = ((inode->i_ino - 1) % | |
4132 | EXT4_INODES_PER_GROUP(sb)); | |
4133 | block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block); | |
4134 | iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb); | |
4135 | ||
4136 | bh = sb_getblk(sb, block); | |
ac27a0ec | 4137 | if (!bh) { |
240799cd TT |
4138 | ext4_error(sb, "ext4_get_inode_loc", "unable to read " |
4139 | "inode block - inode=%lu, block=%llu", | |
4140 | inode->i_ino, block); | |
ac27a0ec DK |
4141 | return -EIO; |
4142 | } | |
4143 | if (!buffer_uptodate(bh)) { | |
4144 | lock_buffer(bh); | |
9c83a923 HK |
4145 | |
4146 | /* | |
4147 | * If the buffer has the write error flag, we have failed | |
4148 | * to write out another inode in the same block. In this | |
4149 | * case, we don't have to read the block because we may | |
4150 | * read the old inode data successfully. | |
4151 | */ | |
4152 | if (buffer_write_io_error(bh) && !buffer_uptodate(bh)) | |
4153 | set_buffer_uptodate(bh); | |
4154 | ||
ac27a0ec DK |
4155 | if (buffer_uptodate(bh)) { |
4156 | /* someone brought it uptodate while we waited */ | |
4157 | unlock_buffer(bh); | |
4158 | goto has_buffer; | |
4159 | } | |
4160 | ||
4161 | /* | |
4162 | * If we have all information of the inode in memory and this | |
4163 | * is the only valid inode in the block, we need not read the | |
4164 | * block. | |
4165 | */ | |
4166 | if (in_mem) { | |
4167 | struct buffer_head *bitmap_bh; | |
240799cd | 4168 | int i, start; |
ac27a0ec | 4169 | |
240799cd | 4170 | start = inode_offset & ~(inodes_per_block - 1); |
ac27a0ec | 4171 | |
240799cd TT |
4172 | /* Is the inode bitmap in cache? */ |
4173 | bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp)); | |
ac27a0ec DK |
4174 | if (!bitmap_bh) |
4175 | goto make_io; | |
4176 | ||
4177 | /* | |
4178 | * If the inode bitmap isn't in cache then the | |
4179 | * optimisation may end up performing two reads instead | |
4180 | * of one, so skip it. | |
4181 | */ | |
4182 | if (!buffer_uptodate(bitmap_bh)) { | |
4183 | brelse(bitmap_bh); | |
4184 | goto make_io; | |
4185 | } | |
240799cd | 4186 | for (i = start; i < start + inodes_per_block; i++) { |
ac27a0ec DK |
4187 | if (i == inode_offset) |
4188 | continue; | |
617ba13b | 4189 | if (ext4_test_bit(i, bitmap_bh->b_data)) |
ac27a0ec DK |
4190 | break; |
4191 | } | |
4192 | brelse(bitmap_bh); | |
240799cd | 4193 | if (i == start + inodes_per_block) { |
ac27a0ec DK |
4194 | /* all other inodes are free, so skip I/O */ |
4195 | memset(bh->b_data, 0, bh->b_size); | |
4196 | set_buffer_uptodate(bh); | |
4197 | unlock_buffer(bh); | |
4198 | goto has_buffer; | |
4199 | } | |
4200 | } | |
4201 | ||
4202 | make_io: | |
240799cd TT |
4203 | /* |
4204 | * If we need to do any I/O, try to pre-readahead extra | |
4205 | * blocks from the inode table. | |
4206 | */ | |
4207 | if (EXT4_SB(sb)->s_inode_readahead_blks) { | |
4208 | ext4_fsblk_t b, end, table; | |
4209 | unsigned num; | |
4210 | ||
4211 | table = ext4_inode_table(sb, gdp); | |
b713a5ec | 4212 | /* s_inode_readahead_blks is always a power of 2 */ |
240799cd TT |
4213 | b = block & ~(EXT4_SB(sb)->s_inode_readahead_blks-1); |
4214 | if (table > b) | |
4215 | b = table; | |
4216 | end = b + EXT4_SB(sb)->s_inode_readahead_blks; | |
4217 | num = EXT4_INODES_PER_GROUP(sb); | |
4218 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4219 | EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) | |
560671a0 | 4220 | num -= ext4_itable_unused_count(sb, gdp); |
240799cd TT |
4221 | table += num / inodes_per_block; |
4222 | if (end > table) | |
4223 | end = table; | |
4224 | while (b <= end) | |
4225 | sb_breadahead(sb, b++); | |
4226 | } | |
4227 | ||
ac27a0ec DK |
4228 | /* |
4229 | * There are other valid inodes in the buffer, this inode | |
4230 | * has in-inode xattrs, or we don't have this inode in memory. | |
4231 | * Read the block from disk. | |
4232 | */ | |
4233 | get_bh(bh); | |
4234 | bh->b_end_io = end_buffer_read_sync; | |
4235 | submit_bh(READ_META, bh); | |
4236 | wait_on_buffer(bh); | |
4237 | if (!buffer_uptodate(bh)) { | |
240799cd TT |
4238 | ext4_error(sb, __func__, |
4239 | "unable to read inode block - inode=%lu, " | |
4240 | "block=%llu", inode->i_ino, block); | |
ac27a0ec DK |
4241 | brelse(bh); |
4242 | return -EIO; | |
4243 | } | |
4244 | } | |
4245 | has_buffer: | |
4246 | iloc->bh = bh; | |
4247 | return 0; | |
4248 | } | |
4249 | ||
617ba13b | 4250 | int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) |
ac27a0ec DK |
4251 | { |
4252 | /* We have all inode data except xattrs in memory here. */ | |
617ba13b MC |
4253 | return __ext4_get_inode_loc(inode, iloc, |
4254 | !(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)); | |
ac27a0ec DK |
4255 | } |
4256 | ||
617ba13b | 4257 | void ext4_set_inode_flags(struct inode *inode) |
ac27a0ec | 4258 | { |
617ba13b | 4259 | unsigned int flags = EXT4_I(inode)->i_flags; |
ac27a0ec DK |
4260 | |
4261 | inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); | |
617ba13b | 4262 | if (flags & EXT4_SYNC_FL) |
ac27a0ec | 4263 | inode->i_flags |= S_SYNC; |
617ba13b | 4264 | if (flags & EXT4_APPEND_FL) |
ac27a0ec | 4265 | inode->i_flags |= S_APPEND; |
617ba13b | 4266 | if (flags & EXT4_IMMUTABLE_FL) |
ac27a0ec | 4267 | inode->i_flags |= S_IMMUTABLE; |
617ba13b | 4268 | if (flags & EXT4_NOATIME_FL) |
ac27a0ec | 4269 | inode->i_flags |= S_NOATIME; |
617ba13b | 4270 | if (flags & EXT4_DIRSYNC_FL) |
ac27a0ec DK |
4271 | inode->i_flags |= S_DIRSYNC; |
4272 | } | |
4273 | ||
ff9ddf7e JK |
4274 | /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */ |
4275 | void ext4_get_inode_flags(struct ext4_inode_info *ei) | |
4276 | { | |
4277 | unsigned int flags = ei->vfs_inode.i_flags; | |
4278 | ||
4279 | ei->i_flags &= ~(EXT4_SYNC_FL|EXT4_APPEND_FL| | |
4280 | EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|EXT4_DIRSYNC_FL); | |
4281 | if (flags & S_SYNC) | |
4282 | ei->i_flags |= EXT4_SYNC_FL; | |
4283 | if (flags & S_APPEND) | |
4284 | ei->i_flags |= EXT4_APPEND_FL; | |
4285 | if (flags & S_IMMUTABLE) | |
4286 | ei->i_flags |= EXT4_IMMUTABLE_FL; | |
4287 | if (flags & S_NOATIME) | |
4288 | ei->i_flags |= EXT4_NOATIME_FL; | |
4289 | if (flags & S_DIRSYNC) | |
4290 | ei->i_flags |= EXT4_DIRSYNC_FL; | |
4291 | } | |
de9a55b8 | 4292 | |
0fc1b451 | 4293 | static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode, |
de9a55b8 | 4294 | struct ext4_inode_info *ei) |
0fc1b451 AK |
4295 | { |
4296 | blkcnt_t i_blocks ; | |
8180a562 AK |
4297 | struct inode *inode = &(ei->vfs_inode); |
4298 | struct super_block *sb = inode->i_sb; | |
0fc1b451 AK |
4299 | |
4300 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4301 | EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) { | |
4302 | /* we are using combined 48 bit field */ | |
4303 | i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 | | |
4304 | le32_to_cpu(raw_inode->i_blocks_lo); | |
8180a562 AK |
4305 | if (ei->i_flags & EXT4_HUGE_FILE_FL) { |
4306 | /* i_blocks represent file system block size */ | |
4307 | return i_blocks << (inode->i_blkbits - 9); | |
4308 | } else { | |
4309 | return i_blocks; | |
4310 | } | |
0fc1b451 AK |
4311 | } else { |
4312 | return le32_to_cpu(raw_inode->i_blocks_lo); | |
4313 | } | |
4314 | } | |
ff9ddf7e | 4315 | |
1d1fe1ee | 4316 | struct inode *ext4_iget(struct super_block *sb, unsigned long ino) |
ac27a0ec | 4317 | { |
617ba13b MC |
4318 | struct ext4_iloc iloc; |
4319 | struct ext4_inode *raw_inode; | |
1d1fe1ee | 4320 | struct ext4_inode_info *ei; |
ac27a0ec | 4321 | struct buffer_head *bh; |
1d1fe1ee DH |
4322 | struct inode *inode; |
4323 | long ret; | |
ac27a0ec DK |
4324 | int block; |
4325 | ||
1d1fe1ee DH |
4326 | inode = iget_locked(sb, ino); |
4327 | if (!inode) | |
4328 | return ERR_PTR(-ENOMEM); | |
4329 | if (!(inode->i_state & I_NEW)) | |
4330 | return inode; | |
4331 | ||
4332 | ei = EXT4_I(inode); | |
ac27a0ec | 4333 | |
1d1fe1ee DH |
4334 | ret = __ext4_get_inode_loc(inode, &iloc, 0); |
4335 | if (ret < 0) | |
ac27a0ec DK |
4336 | goto bad_inode; |
4337 | bh = iloc.bh; | |
617ba13b | 4338 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec DK |
4339 | inode->i_mode = le16_to_cpu(raw_inode->i_mode); |
4340 | inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); | |
4341 | inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); | |
af5bc92d | 4342 | if (!(test_opt(inode->i_sb, NO_UID32))) { |
ac27a0ec DK |
4343 | inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; |
4344 | inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; | |
4345 | } | |
4346 | inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); | |
ac27a0ec DK |
4347 | |
4348 | ei->i_state = 0; | |
4349 | ei->i_dir_start_lookup = 0; | |
4350 | ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); | |
4351 | /* We now have enough fields to check if the inode was active or not. | |
4352 | * This is needed because nfsd might try to access dead inodes | |
4353 | * the test is that same one that e2fsck uses | |
4354 | * NeilBrown 1999oct15 | |
4355 | */ | |
4356 | if (inode->i_nlink == 0) { | |
4357 | if (inode->i_mode == 0 || | |
617ba13b | 4358 | !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) { |
ac27a0ec | 4359 | /* this inode is deleted */ |
af5bc92d | 4360 | brelse(bh); |
1d1fe1ee | 4361 | ret = -ESTALE; |
ac27a0ec DK |
4362 | goto bad_inode; |
4363 | } | |
4364 | /* The only unlinked inodes we let through here have | |
4365 | * valid i_mode and are being read by the orphan | |
4366 | * recovery code: that's fine, we're about to complete | |
4367 | * the process of deleting those. */ | |
4368 | } | |
ac27a0ec | 4369 | ei->i_flags = le32_to_cpu(raw_inode->i_flags); |
0fc1b451 | 4370 | inode->i_blocks = ext4_inode_blocks(raw_inode, ei); |
7973c0c1 | 4371 | ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo); |
a9e81742 | 4372 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) |
a1ddeb7e BP |
4373 | ei->i_file_acl |= |
4374 | ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32; | |
a48380f7 | 4375 | inode->i_size = ext4_isize(raw_inode); |
ac27a0ec DK |
4376 | ei->i_disksize = inode->i_size; |
4377 | inode->i_generation = le32_to_cpu(raw_inode->i_generation); | |
4378 | ei->i_block_group = iloc.block_group; | |
a4912123 | 4379 | ei->i_last_alloc_group = ~0; |
ac27a0ec DK |
4380 | /* |
4381 | * NOTE! The in-memory inode i_data array is in little-endian order | |
4382 | * even on big-endian machines: we do NOT byteswap the block numbers! | |
4383 | */ | |
617ba13b | 4384 | for (block = 0; block < EXT4_N_BLOCKS; block++) |
ac27a0ec DK |
4385 | ei->i_data[block] = raw_inode->i_block[block]; |
4386 | INIT_LIST_HEAD(&ei->i_orphan); | |
4387 | ||
0040d987 | 4388 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { |
ac27a0ec | 4389 | ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); |
617ba13b | 4390 | if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > |
e5d2861f | 4391 | EXT4_INODE_SIZE(inode->i_sb)) { |
af5bc92d | 4392 | brelse(bh); |
1d1fe1ee | 4393 | ret = -EIO; |
ac27a0ec | 4394 | goto bad_inode; |
e5d2861f | 4395 | } |
ac27a0ec DK |
4396 | if (ei->i_extra_isize == 0) { |
4397 | /* The extra space is currently unused. Use it. */ | |
617ba13b MC |
4398 | ei->i_extra_isize = sizeof(struct ext4_inode) - |
4399 | EXT4_GOOD_OLD_INODE_SIZE; | |
ac27a0ec DK |
4400 | } else { |
4401 | __le32 *magic = (void *)raw_inode + | |
617ba13b | 4402 | EXT4_GOOD_OLD_INODE_SIZE + |
ac27a0ec | 4403 | ei->i_extra_isize; |
617ba13b | 4404 | if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC)) |
de9a55b8 | 4405 | ei->i_state |= EXT4_STATE_XATTR; |
ac27a0ec DK |
4406 | } |
4407 | } else | |
4408 | ei->i_extra_isize = 0; | |
4409 | ||
ef7f3835 KS |
4410 | EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode); |
4411 | EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode); | |
4412 | EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode); | |
4413 | EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode); | |
4414 | ||
25ec56b5 JNC |
4415 | inode->i_version = le32_to_cpu(raw_inode->i_disk_version); |
4416 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { | |
4417 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) | |
4418 | inode->i_version |= | |
4419 | (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32; | |
4420 | } | |
4421 | ||
c4b5a614 | 4422 | ret = 0; |
485c26ec | 4423 | if (ei->i_file_acl && |
de9a55b8 | 4424 | ((ei->i_file_acl < |
485c26ec TT |
4425 | (le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) + |
4426 | EXT4_SB(sb)->s_gdb_count)) || | |
4427 | (ei->i_file_acl >= ext4_blocks_count(EXT4_SB(sb)->s_es)))) { | |
4428 | ext4_error(sb, __func__, | |
4429 | "bad extended attribute block %llu in inode #%lu", | |
4430 | ei->i_file_acl, inode->i_ino); | |
4431 | ret = -EIO; | |
4432 | goto bad_inode; | |
4433 | } else if (ei->i_flags & EXT4_EXTENTS_FL) { | |
c4b5a614 TT |
4434 | if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
4435 | (S_ISLNK(inode->i_mode) && | |
4436 | !ext4_inode_is_fast_symlink(inode))) | |
4437 | /* Validate extent which is part of inode */ | |
4438 | ret = ext4_ext_check_inode(inode); | |
de9a55b8 | 4439 | } else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
fe2c8191 TN |
4440 | (S_ISLNK(inode->i_mode) && |
4441 | !ext4_inode_is_fast_symlink(inode))) { | |
de9a55b8 | 4442 | /* Validate block references which are part of inode */ |
fe2c8191 TN |
4443 | ret = ext4_check_inode_blockref(inode); |
4444 | } | |
4445 | if (ret) { | |
de9a55b8 TT |
4446 | brelse(bh); |
4447 | goto bad_inode; | |
7a262f7c AK |
4448 | } |
4449 | ||
ac27a0ec | 4450 | if (S_ISREG(inode->i_mode)) { |
617ba13b MC |
4451 | inode->i_op = &ext4_file_inode_operations; |
4452 | inode->i_fop = &ext4_file_operations; | |
4453 | ext4_set_aops(inode); | |
ac27a0ec | 4454 | } else if (S_ISDIR(inode->i_mode)) { |
617ba13b MC |
4455 | inode->i_op = &ext4_dir_inode_operations; |
4456 | inode->i_fop = &ext4_dir_operations; | |
ac27a0ec | 4457 | } else if (S_ISLNK(inode->i_mode)) { |
e83c1397 | 4458 | if (ext4_inode_is_fast_symlink(inode)) { |
617ba13b | 4459 | inode->i_op = &ext4_fast_symlink_inode_operations; |
e83c1397 DG |
4460 | nd_terminate_link(ei->i_data, inode->i_size, |
4461 | sizeof(ei->i_data) - 1); | |
4462 | } else { | |
617ba13b MC |
4463 | inode->i_op = &ext4_symlink_inode_operations; |
4464 | ext4_set_aops(inode); | |
ac27a0ec | 4465 | } |
563bdd61 TT |
4466 | } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || |
4467 | S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { | |
617ba13b | 4468 | inode->i_op = &ext4_special_inode_operations; |
ac27a0ec DK |
4469 | if (raw_inode->i_block[0]) |
4470 | init_special_inode(inode, inode->i_mode, | |
4471 | old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); | |
4472 | else | |
4473 | init_special_inode(inode, inode->i_mode, | |
4474 | new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); | |
563bdd61 TT |
4475 | } else { |
4476 | brelse(bh); | |
4477 | ret = -EIO; | |
de9a55b8 | 4478 | ext4_error(inode->i_sb, __func__, |
563bdd61 TT |
4479 | "bogus i_mode (%o) for inode=%lu", |
4480 | inode->i_mode, inode->i_ino); | |
4481 | goto bad_inode; | |
ac27a0ec | 4482 | } |
af5bc92d | 4483 | brelse(iloc.bh); |
617ba13b | 4484 | ext4_set_inode_flags(inode); |
1d1fe1ee DH |
4485 | unlock_new_inode(inode); |
4486 | return inode; | |
ac27a0ec DK |
4487 | |
4488 | bad_inode: | |
1d1fe1ee DH |
4489 | iget_failed(inode); |
4490 | return ERR_PTR(ret); | |
ac27a0ec DK |
4491 | } |
4492 | ||
0fc1b451 AK |
4493 | static int ext4_inode_blocks_set(handle_t *handle, |
4494 | struct ext4_inode *raw_inode, | |
4495 | struct ext4_inode_info *ei) | |
4496 | { | |
4497 | struct inode *inode = &(ei->vfs_inode); | |
4498 | u64 i_blocks = inode->i_blocks; | |
4499 | struct super_block *sb = inode->i_sb; | |
0fc1b451 AK |
4500 | |
4501 | if (i_blocks <= ~0U) { | |
4502 | /* | |
4503 | * i_blocks can be represnted in a 32 bit variable | |
4504 | * as multiple of 512 bytes | |
4505 | */ | |
8180a562 | 4506 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
0fc1b451 | 4507 | raw_inode->i_blocks_high = 0; |
8180a562 | 4508 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
f287a1a5 TT |
4509 | return 0; |
4510 | } | |
4511 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) | |
4512 | return -EFBIG; | |
4513 | ||
4514 | if (i_blocks <= 0xffffffffffffULL) { | |
0fc1b451 AK |
4515 | /* |
4516 | * i_blocks can be represented in a 48 bit variable | |
4517 | * as multiple of 512 bytes | |
4518 | */ | |
8180a562 | 4519 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
0fc1b451 | 4520 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); |
8180a562 | 4521 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
0fc1b451 | 4522 | } else { |
8180a562 AK |
4523 | ei->i_flags |= EXT4_HUGE_FILE_FL; |
4524 | /* i_block is stored in file system block size */ | |
4525 | i_blocks = i_blocks >> (inode->i_blkbits - 9); | |
4526 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); | |
4527 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); | |
0fc1b451 | 4528 | } |
f287a1a5 | 4529 | return 0; |
0fc1b451 AK |
4530 | } |
4531 | ||
ac27a0ec DK |
4532 | /* |
4533 | * Post the struct inode info into an on-disk inode location in the | |
4534 | * buffer-cache. This gobbles the caller's reference to the | |
4535 | * buffer_head in the inode location struct. | |
4536 | * | |
4537 | * The caller must have write access to iloc->bh. | |
4538 | */ | |
617ba13b | 4539 | static int ext4_do_update_inode(handle_t *handle, |
ac27a0ec | 4540 | struct inode *inode, |
617ba13b | 4541 | struct ext4_iloc *iloc) |
ac27a0ec | 4542 | { |
617ba13b MC |
4543 | struct ext4_inode *raw_inode = ext4_raw_inode(iloc); |
4544 | struct ext4_inode_info *ei = EXT4_I(inode); | |
ac27a0ec DK |
4545 | struct buffer_head *bh = iloc->bh; |
4546 | int err = 0, rc, block; | |
4547 | ||
4548 | /* For fields not not tracking in the in-memory inode, | |
4549 | * initialise them to zero for new inodes. */ | |
617ba13b MC |
4550 | if (ei->i_state & EXT4_STATE_NEW) |
4551 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); | |
ac27a0ec | 4552 | |
ff9ddf7e | 4553 | ext4_get_inode_flags(ei); |
ac27a0ec | 4554 | raw_inode->i_mode = cpu_to_le16(inode->i_mode); |
af5bc92d | 4555 | if (!(test_opt(inode->i_sb, NO_UID32))) { |
ac27a0ec DK |
4556 | raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid)); |
4557 | raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid)); | |
4558 | /* | |
4559 | * Fix up interoperability with old kernels. Otherwise, old inodes get | |
4560 | * re-used with the upper 16 bits of the uid/gid intact | |
4561 | */ | |
af5bc92d | 4562 | if (!ei->i_dtime) { |
ac27a0ec DK |
4563 | raw_inode->i_uid_high = |
4564 | cpu_to_le16(high_16_bits(inode->i_uid)); | |
4565 | raw_inode->i_gid_high = | |
4566 | cpu_to_le16(high_16_bits(inode->i_gid)); | |
4567 | } else { | |
4568 | raw_inode->i_uid_high = 0; | |
4569 | raw_inode->i_gid_high = 0; | |
4570 | } | |
4571 | } else { | |
4572 | raw_inode->i_uid_low = | |
4573 | cpu_to_le16(fs_high2lowuid(inode->i_uid)); | |
4574 | raw_inode->i_gid_low = | |
4575 | cpu_to_le16(fs_high2lowgid(inode->i_gid)); | |
4576 | raw_inode->i_uid_high = 0; | |
4577 | raw_inode->i_gid_high = 0; | |
4578 | } | |
4579 | raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); | |
ef7f3835 KS |
4580 | |
4581 | EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode); | |
4582 | EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode); | |
4583 | EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode); | |
4584 | EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode); | |
4585 | ||
0fc1b451 AK |
4586 | if (ext4_inode_blocks_set(handle, raw_inode, ei)) |
4587 | goto out_brelse; | |
ac27a0ec | 4588 | raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); |
267e4db9 AK |
4589 | /* clear the migrate flag in the raw_inode */ |
4590 | raw_inode->i_flags = cpu_to_le32(ei->i_flags & ~EXT4_EXT_MIGRATE); | |
9b8f1f01 MC |
4591 | if (EXT4_SB(inode->i_sb)->s_es->s_creator_os != |
4592 | cpu_to_le32(EXT4_OS_HURD)) | |
a1ddeb7e BP |
4593 | raw_inode->i_file_acl_high = |
4594 | cpu_to_le16(ei->i_file_acl >> 32); | |
7973c0c1 | 4595 | raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl); |
a48380f7 AK |
4596 | ext4_isize_set(raw_inode, ei->i_disksize); |
4597 | if (ei->i_disksize > 0x7fffffffULL) { | |
4598 | struct super_block *sb = inode->i_sb; | |
4599 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4600 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE) || | |
4601 | EXT4_SB(sb)->s_es->s_rev_level == | |
4602 | cpu_to_le32(EXT4_GOOD_OLD_REV)) { | |
4603 | /* If this is the first large file | |
4604 | * created, add a flag to the superblock. | |
4605 | */ | |
4606 | err = ext4_journal_get_write_access(handle, | |
4607 | EXT4_SB(sb)->s_sbh); | |
4608 | if (err) | |
4609 | goto out_brelse; | |
4610 | ext4_update_dynamic_rev(sb); | |
4611 | EXT4_SET_RO_COMPAT_FEATURE(sb, | |
617ba13b | 4612 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE); |
a48380f7 | 4613 | sb->s_dirt = 1; |
0390131b FM |
4614 | ext4_handle_sync(handle); |
4615 | err = ext4_handle_dirty_metadata(handle, inode, | |
a48380f7 | 4616 | EXT4_SB(sb)->s_sbh); |
ac27a0ec DK |
4617 | } |
4618 | } | |
4619 | raw_inode->i_generation = cpu_to_le32(inode->i_generation); | |
4620 | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { | |
4621 | if (old_valid_dev(inode->i_rdev)) { | |
4622 | raw_inode->i_block[0] = | |
4623 | cpu_to_le32(old_encode_dev(inode->i_rdev)); | |
4624 | raw_inode->i_block[1] = 0; | |
4625 | } else { | |
4626 | raw_inode->i_block[0] = 0; | |
4627 | raw_inode->i_block[1] = | |
4628 | cpu_to_le32(new_encode_dev(inode->i_rdev)); | |
4629 | raw_inode->i_block[2] = 0; | |
4630 | } | |
de9a55b8 TT |
4631 | } else |
4632 | for (block = 0; block < EXT4_N_BLOCKS; block++) | |
4633 | raw_inode->i_block[block] = ei->i_data[block]; | |
ac27a0ec | 4634 | |
25ec56b5 JNC |
4635 | raw_inode->i_disk_version = cpu_to_le32(inode->i_version); |
4636 | if (ei->i_extra_isize) { | |
4637 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) | |
4638 | raw_inode->i_version_hi = | |
4639 | cpu_to_le32(inode->i_version >> 32); | |
ac27a0ec | 4640 | raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); |
25ec56b5 JNC |
4641 | } |
4642 | ||
0390131b FM |
4643 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
4644 | rc = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
4645 | if (!err) |
4646 | err = rc; | |
617ba13b | 4647 | ei->i_state &= ~EXT4_STATE_NEW; |
ac27a0ec DK |
4648 | |
4649 | out_brelse: | |
af5bc92d | 4650 | brelse(bh); |
617ba13b | 4651 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
4652 | return err; |
4653 | } | |
4654 | ||
4655 | /* | |
617ba13b | 4656 | * ext4_write_inode() |
ac27a0ec DK |
4657 | * |
4658 | * We are called from a few places: | |
4659 | * | |
4660 | * - Within generic_file_write() for O_SYNC files. | |
4661 | * Here, there will be no transaction running. We wait for any running | |
4662 | * trasnaction to commit. | |
4663 | * | |
4664 | * - Within sys_sync(), kupdate and such. | |
4665 | * We wait on commit, if tol to. | |
4666 | * | |
4667 | * - Within prune_icache() (PF_MEMALLOC == true) | |
4668 | * Here we simply return. We can't afford to block kswapd on the | |
4669 | * journal commit. | |
4670 | * | |
4671 | * In all cases it is actually safe for us to return without doing anything, | |
4672 | * because the inode has been copied into a raw inode buffer in | |
617ba13b | 4673 | * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for |
ac27a0ec DK |
4674 | * knfsd. |
4675 | * | |
4676 | * Note that we are absolutely dependent upon all inode dirtiers doing the | |
4677 | * right thing: they *must* call mark_inode_dirty() after dirtying info in | |
4678 | * which we are interested. | |
4679 | * | |
4680 | * It would be a bug for them to not do this. The code: | |
4681 | * | |
4682 | * mark_inode_dirty(inode) | |
4683 | * stuff(); | |
4684 | * inode->i_size = expr; | |
4685 | * | |
4686 | * is in error because a kswapd-driven write_inode() could occur while | |
4687 | * `stuff()' is running, and the new i_size will be lost. Plus the inode | |
4688 | * will no longer be on the superblock's dirty inode list. | |
4689 | */ | |
617ba13b | 4690 | int ext4_write_inode(struct inode *inode, int wait) |
ac27a0ec DK |
4691 | { |
4692 | if (current->flags & PF_MEMALLOC) | |
4693 | return 0; | |
4694 | ||
617ba13b | 4695 | if (ext4_journal_current_handle()) { |
b38bd33a | 4696 | jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n"); |
ac27a0ec DK |
4697 | dump_stack(); |
4698 | return -EIO; | |
4699 | } | |
4700 | ||
4701 | if (!wait) | |
4702 | return 0; | |
4703 | ||
617ba13b | 4704 | return ext4_force_commit(inode->i_sb); |
ac27a0ec DK |
4705 | } |
4706 | ||
4707 | /* | |
617ba13b | 4708 | * ext4_setattr() |
ac27a0ec DK |
4709 | * |
4710 | * Called from notify_change. | |
4711 | * | |
4712 | * We want to trap VFS attempts to truncate the file as soon as | |
4713 | * possible. In particular, we want to make sure that when the VFS | |
4714 | * shrinks i_size, we put the inode on the orphan list and modify | |
4715 | * i_disksize immediately, so that during the subsequent flushing of | |
4716 | * dirty pages and freeing of disk blocks, we can guarantee that any | |
4717 | * commit will leave the blocks being flushed in an unused state on | |
4718 | * disk. (On recovery, the inode will get truncated and the blocks will | |
4719 | * be freed, so we have a strong guarantee that no future commit will | |
4720 | * leave these blocks visible to the user.) | |
4721 | * | |
678aaf48 JK |
4722 | * Another thing we have to assure is that if we are in ordered mode |
4723 | * and inode is still attached to the committing transaction, we must | |
4724 | * we start writeout of all the dirty pages which are being truncated. | |
4725 | * This way we are sure that all the data written in the previous | |
4726 | * transaction are already on disk (truncate waits for pages under | |
4727 | * writeback). | |
4728 | * | |
4729 | * Called with inode->i_mutex down. | |
ac27a0ec | 4730 | */ |
617ba13b | 4731 | int ext4_setattr(struct dentry *dentry, struct iattr *attr) |
ac27a0ec DK |
4732 | { |
4733 | struct inode *inode = dentry->d_inode; | |
4734 | int error, rc = 0; | |
4735 | const unsigned int ia_valid = attr->ia_valid; | |
4736 | ||
4737 | error = inode_change_ok(inode, attr); | |
4738 | if (error) | |
4739 | return error; | |
4740 | ||
4741 | if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || | |
4742 | (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) { | |
4743 | handle_t *handle; | |
4744 | ||
4745 | /* (user+group)*(old+new) structure, inode write (sb, | |
4746 | * inode block, ? - but truncate inode update has it) */ | |
617ba13b MC |
4747 | handle = ext4_journal_start(inode, 2*(EXT4_QUOTA_INIT_BLOCKS(inode->i_sb)+ |
4748 | EXT4_QUOTA_DEL_BLOCKS(inode->i_sb))+3); | |
ac27a0ec DK |
4749 | if (IS_ERR(handle)) { |
4750 | error = PTR_ERR(handle); | |
4751 | goto err_out; | |
4752 | } | |
a269eb18 | 4753 | error = vfs_dq_transfer(inode, attr) ? -EDQUOT : 0; |
ac27a0ec | 4754 | if (error) { |
617ba13b | 4755 | ext4_journal_stop(handle); |
ac27a0ec DK |
4756 | return error; |
4757 | } | |
4758 | /* Update corresponding info in inode so that everything is in | |
4759 | * one transaction */ | |
4760 | if (attr->ia_valid & ATTR_UID) | |
4761 | inode->i_uid = attr->ia_uid; | |
4762 | if (attr->ia_valid & ATTR_GID) | |
4763 | inode->i_gid = attr->ia_gid; | |
617ba13b MC |
4764 | error = ext4_mark_inode_dirty(handle, inode); |
4765 | ext4_journal_stop(handle); | |
ac27a0ec DK |
4766 | } |
4767 | ||
e2b46574 ES |
4768 | if (attr->ia_valid & ATTR_SIZE) { |
4769 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) { | |
4770 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
4771 | ||
4772 | if (attr->ia_size > sbi->s_bitmap_maxbytes) { | |
4773 | error = -EFBIG; | |
4774 | goto err_out; | |
4775 | } | |
4776 | } | |
4777 | } | |
4778 | ||
ac27a0ec DK |
4779 | if (S_ISREG(inode->i_mode) && |
4780 | attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { | |
4781 | handle_t *handle; | |
4782 | ||
617ba13b | 4783 | handle = ext4_journal_start(inode, 3); |
ac27a0ec DK |
4784 | if (IS_ERR(handle)) { |
4785 | error = PTR_ERR(handle); | |
4786 | goto err_out; | |
4787 | } | |
4788 | ||
617ba13b MC |
4789 | error = ext4_orphan_add(handle, inode); |
4790 | EXT4_I(inode)->i_disksize = attr->ia_size; | |
4791 | rc = ext4_mark_inode_dirty(handle, inode); | |
ac27a0ec DK |
4792 | if (!error) |
4793 | error = rc; | |
617ba13b | 4794 | ext4_journal_stop(handle); |
678aaf48 JK |
4795 | |
4796 | if (ext4_should_order_data(inode)) { | |
4797 | error = ext4_begin_ordered_truncate(inode, | |
4798 | attr->ia_size); | |
4799 | if (error) { | |
4800 | /* Do as much error cleanup as possible */ | |
4801 | handle = ext4_journal_start(inode, 3); | |
4802 | if (IS_ERR(handle)) { | |
4803 | ext4_orphan_del(NULL, inode); | |
4804 | goto err_out; | |
4805 | } | |
4806 | ext4_orphan_del(handle, inode); | |
4807 | ext4_journal_stop(handle); | |
4808 | goto err_out; | |
4809 | } | |
4810 | } | |
ac27a0ec DK |
4811 | } |
4812 | ||
4813 | rc = inode_setattr(inode, attr); | |
4814 | ||
617ba13b | 4815 | /* If inode_setattr's call to ext4_truncate failed to get a |
ac27a0ec DK |
4816 | * transaction handle at all, we need to clean up the in-core |
4817 | * orphan list manually. */ | |
4818 | if (inode->i_nlink) | |
617ba13b | 4819 | ext4_orphan_del(NULL, inode); |
ac27a0ec DK |
4820 | |
4821 | if (!rc && (ia_valid & ATTR_MODE)) | |
617ba13b | 4822 | rc = ext4_acl_chmod(inode); |
ac27a0ec DK |
4823 | |
4824 | err_out: | |
617ba13b | 4825 | ext4_std_error(inode->i_sb, error); |
ac27a0ec DK |
4826 | if (!error) |
4827 | error = rc; | |
4828 | return error; | |
4829 | } | |
4830 | ||
3e3398a0 MC |
4831 | int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, |
4832 | struct kstat *stat) | |
4833 | { | |
4834 | struct inode *inode; | |
4835 | unsigned long delalloc_blocks; | |
4836 | ||
4837 | inode = dentry->d_inode; | |
4838 | generic_fillattr(inode, stat); | |
4839 | ||
4840 | /* | |
4841 | * We can't update i_blocks if the block allocation is delayed | |
4842 | * otherwise in the case of system crash before the real block | |
4843 | * allocation is done, we will have i_blocks inconsistent with | |
4844 | * on-disk file blocks. | |
4845 | * We always keep i_blocks updated together with real | |
4846 | * allocation. But to not confuse with user, stat | |
4847 | * will return the blocks that include the delayed allocation | |
4848 | * blocks for this file. | |
4849 | */ | |
4850 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
4851 | delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks; | |
4852 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
4853 | ||
4854 | stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9; | |
4855 | return 0; | |
4856 | } | |
ac27a0ec | 4857 | |
a02908f1 MC |
4858 | static int ext4_indirect_trans_blocks(struct inode *inode, int nrblocks, |
4859 | int chunk) | |
4860 | { | |
4861 | int indirects; | |
4862 | ||
4863 | /* if nrblocks are contiguous */ | |
4864 | if (chunk) { | |
4865 | /* | |
4866 | * With N contiguous data blocks, it need at most | |
4867 | * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) indirect blocks | |
4868 | * 2 dindirect blocks | |
4869 | * 1 tindirect block | |
4870 | */ | |
4871 | indirects = nrblocks / EXT4_ADDR_PER_BLOCK(inode->i_sb); | |
4872 | return indirects + 3; | |
4873 | } | |
4874 | /* | |
4875 | * if nrblocks are not contiguous, worse case, each block touch | |
4876 | * a indirect block, and each indirect block touch a double indirect | |
4877 | * block, plus a triple indirect block | |
4878 | */ | |
4879 | indirects = nrblocks * 2 + 1; | |
4880 | return indirects; | |
4881 | } | |
4882 | ||
4883 | static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
4884 | { | |
4885 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) | |
ac51d837 TT |
4886 | return ext4_indirect_trans_blocks(inode, nrblocks, chunk); |
4887 | return ext4_ext_index_trans_blocks(inode, nrblocks, chunk); | |
a02908f1 | 4888 | } |
ac51d837 | 4889 | |
ac27a0ec | 4890 | /* |
a02908f1 MC |
4891 | * Account for index blocks, block groups bitmaps and block group |
4892 | * descriptor blocks if modify datablocks and index blocks | |
4893 | * worse case, the indexs blocks spread over different block groups | |
ac27a0ec | 4894 | * |
a02908f1 MC |
4895 | * If datablocks are discontiguous, they are possible to spread over |
4896 | * different block groups too. If they are contiugous, with flexbg, | |
4897 | * they could still across block group boundary. | |
ac27a0ec | 4898 | * |
a02908f1 MC |
4899 | * Also account for superblock, inode, quota and xattr blocks |
4900 | */ | |
4901 | int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
4902 | { | |
8df9675f TT |
4903 | ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb); |
4904 | int gdpblocks; | |
a02908f1 MC |
4905 | int idxblocks; |
4906 | int ret = 0; | |
4907 | ||
4908 | /* | |
4909 | * How many index blocks need to touch to modify nrblocks? | |
4910 | * The "Chunk" flag indicating whether the nrblocks is | |
4911 | * physically contiguous on disk | |
4912 | * | |
4913 | * For Direct IO and fallocate, they calls get_block to allocate | |
4914 | * one single extent at a time, so they could set the "Chunk" flag | |
4915 | */ | |
4916 | idxblocks = ext4_index_trans_blocks(inode, nrblocks, chunk); | |
4917 | ||
4918 | ret = idxblocks; | |
4919 | ||
4920 | /* | |
4921 | * Now let's see how many group bitmaps and group descriptors need | |
4922 | * to account | |
4923 | */ | |
4924 | groups = idxblocks; | |
4925 | if (chunk) | |
4926 | groups += 1; | |
4927 | else | |
4928 | groups += nrblocks; | |
4929 | ||
4930 | gdpblocks = groups; | |
8df9675f TT |
4931 | if (groups > ngroups) |
4932 | groups = ngroups; | |
a02908f1 MC |
4933 | if (groups > EXT4_SB(inode->i_sb)->s_gdb_count) |
4934 | gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count; | |
4935 | ||
4936 | /* bitmaps and block group descriptor blocks */ | |
4937 | ret += groups + gdpblocks; | |
4938 | ||
4939 | /* Blocks for super block, inode, quota and xattr blocks */ | |
4940 | ret += EXT4_META_TRANS_BLOCKS(inode->i_sb); | |
4941 | ||
4942 | return ret; | |
4943 | } | |
4944 | ||
4945 | /* | |
4946 | * Calulate the total number of credits to reserve to fit | |
f3bd1f3f MC |
4947 | * the modification of a single pages into a single transaction, |
4948 | * which may include multiple chunks of block allocations. | |
ac27a0ec | 4949 | * |
525f4ed8 | 4950 | * This could be called via ext4_write_begin() |
ac27a0ec | 4951 | * |
525f4ed8 | 4952 | * We need to consider the worse case, when |
a02908f1 | 4953 | * one new block per extent. |
ac27a0ec | 4954 | */ |
a86c6181 | 4955 | int ext4_writepage_trans_blocks(struct inode *inode) |
ac27a0ec | 4956 | { |
617ba13b | 4957 | int bpp = ext4_journal_blocks_per_page(inode); |
ac27a0ec DK |
4958 | int ret; |
4959 | ||
a02908f1 | 4960 | ret = ext4_meta_trans_blocks(inode, bpp, 0); |
a86c6181 | 4961 | |
a02908f1 | 4962 | /* Account for data blocks for journalled mode */ |
617ba13b | 4963 | if (ext4_should_journal_data(inode)) |
a02908f1 | 4964 | ret += bpp; |
ac27a0ec DK |
4965 | return ret; |
4966 | } | |
f3bd1f3f MC |
4967 | |
4968 | /* | |
4969 | * Calculate the journal credits for a chunk of data modification. | |
4970 | * | |
4971 | * This is called from DIO, fallocate or whoever calling | |
12b7ac17 | 4972 | * ext4_get_blocks() to map/allocate a chunk of contigous disk blocks. |
f3bd1f3f MC |
4973 | * |
4974 | * journal buffers for data blocks are not included here, as DIO | |
4975 | * and fallocate do no need to journal data buffers. | |
4976 | */ | |
4977 | int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks) | |
4978 | { | |
4979 | return ext4_meta_trans_blocks(inode, nrblocks, 1); | |
4980 | } | |
4981 | ||
ac27a0ec | 4982 | /* |
617ba13b | 4983 | * The caller must have previously called ext4_reserve_inode_write(). |
ac27a0ec DK |
4984 | * Give this, we know that the caller already has write access to iloc->bh. |
4985 | */ | |
617ba13b | 4986 | int ext4_mark_iloc_dirty(handle_t *handle, |
de9a55b8 | 4987 | struct inode *inode, struct ext4_iloc *iloc) |
ac27a0ec DK |
4988 | { |
4989 | int err = 0; | |
4990 | ||
25ec56b5 JNC |
4991 | if (test_opt(inode->i_sb, I_VERSION)) |
4992 | inode_inc_iversion(inode); | |
4993 | ||
ac27a0ec DK |
4994 | /* the do_update_inode consumes one bh->b_count */ |
4995 | get_bh(iloc->bh); | |
4996 | ||
dab291af | 4997 | /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */ |
617ba13b | 4998 | err = ext4_do_update_inode(handle, inode, iloc); |
ac27a0ec DK |
4999 | put_bh(iloc->bh); |
5000 | return err; | |
5001 | } | |
5002 | ||
5003 | /* | |
5004 | * On success, We end up with an outstanding reference count against | |
5005 | * iloc->bh. This _must_ be cleaned up later. | |
5006 | */ | |
5007 | ||
5008 | int | |
617ba13b MC |
5009 | ext4_reserve_inode_write(handle_t *handle, struct inode *inode, |
5010 | struct ext4_iloc *iloc) | |
ac27a0ec | 5011 | { |
0390131b FM |
5012 | int err; |
5013 | ||
5014 | err = ext4_get_inode_loc(inode, iloc); | |
5015 | if (!err) { | |
5016 | BUFFER_TRACE(iloc->bh, "get_write_access"); | |
5017 | err = ext4_journal_get_write_access(handle, iloc->bh); | |
5018 | if (err) { | |
5019 | brelse(iloc->bh); | |
5020 | iloc->bh = NULL; | |
ac27a0ec DK |
5021 | } |
5022 | } | |
617ba13b | 5023 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5024 | return err; |
5025 | } | |
5026 | ||
6dd4ee7c KS |
5027 | /* |
5028 | * Expand an inode by new_extra_isize bytes. | |
5029 | * Returns 0 on success or negative error number on failure. | |
5030 | */ | |
1d03ec98 AK |
5031 | static int ext4_expand_extra_isize(struct inode *inode, |
5032 | unsigned int new_extra_isize, | |
5033 | struct ext4_iloc iloc, | |
5034 | handle_t *handle) | |
6dd4ee7c KS |
5035 | { |
5036 | struct ext4_inode *raw_inode; | |
5037 | struct ext4_xattr_ibody_header *header; | |
5038 | struct ext4_xattr_entry *entry; | |
5039 | ||
5040 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) | |
5041 | return 0; | |
5042 | ||
5043 | raw_inode = ext4_raw_inode(&iloc); | |
5044 | ||
5045 | header = IHDR(inode, raw_inode); | |
5046 | entry = IFIRST(header); | |
5047 | ||
5048 | /* No extended attributes present */ | |
5049 | if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR) || | |
5050 | header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { | |
5051 | memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0, | |
5052 | new_extra_isize); | |
5053 | EXT4_I(inode)->i_extra_isize = new_extra_isize; | |
5054 | return 0; | |
5055 | } | |
5056 | ||
5057 | /* try to expand with EAs present */ | |
5058 | return ext4_expand_extra_isize_ea(inode, new_extra_isize, | |
5059 | raw_inode, handle); | |
5060 | } | |
5061 | ||
ac27a0ec DK |
5062 | /* |
5063 | * What we do here is to mark the in-core inode as clean with respect to inode | |
5064 | * dirtiness (it may still be data-dirty). | |
5065 | * This means that the in-core inode may be reaped by prune_icache | |
5066 | * without having to perform any I/O. This is a very good thing, | |
5067 | * because *any* task may call prune_icache - even ones which | |
5068 | * have a transaction open against a different journal. | |
5069 | * | |
5070 | * Is this cheating? Not really. Sure, we haven't written the | |
5071 | * inode out, but prune_icache isn't a user-visible syncing function. | |
5072 | * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) | |
5073 | * we start and wait on commits. | |
5074 | * | |
5075 | * Is this efficient/effective? Well, we're being nice to the system | |
5076 | * by cleaning up our inodes proactively so they can be reaped | |
5077 | * without I/O. But we are potentially leaving up to five seconds' | |
5078 | * worth of inodes floating about which prune_icache wants us to | |
5079 | * write out. One way to fix that would be to get prune_icache() | |
5080 | * to do a write_super() to free up some memory. It has the desired | |
5081 | * effect. | |
5082 | */ | |
617ba13b | 5083 | int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode) |
ac27a0ec | 5084 | { |
617ba13b | 5085 | struct ext4_iloc iloc; |
6dd4ee7c KS |
5086 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
5087 | static unsigned int mnt_count; | |
5088 | int err, ret; | |
ac27a0ec DK |
5089 | |
5090 | might_sleep(); | |
617ba13b | 5091 | err = ext4_reserve_inode_write(handle, inode, &iloc); |
0390131b FM |
5092 | if (ext4_handle_valid(handle) && |
5093 | EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize && | |
6dd4ee7c KS |
5094 | !(EXT4_I(inode)->i_state & EXT4_STATE_NO_EXPAND)) { |
5095 | /* | |
5096 | * We need extra buffer credits since we may write into EA block | |
5097 | * with this same handle. If journal_extend fails, then it will | |
5098 | * only result in a minor loss of functionality for that inode. | |
5099 | * If this is felt to be critical, then e2fsck should be run to | |
5100 | * force a large enough s_min_extra_isize. | |
5101 | */ | |
5102 | if ((jbd2_journal_extend(handle, | |
5103 | EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) { | |
5104 | ret = ext4_expand_extra_isize(inode, | |
5105 | sbi->s_want_extra_isize, | |
5106 | iloc, handle); | |
5107 | if (ret) { | |
5108 | EXT4_I(inode)->i_state |= EXT4_STATE_NO_EXPAND; | |
c1bddad9 AK |
5109 | if (mnt_count != |
5110 | le16_to_cpu(sbi->s_es->s_mnt_count)) { | |
46e665e9 | 5111 | ext4_warning(inode->i_sb, __func__, |
6dd4ee7c KS |
5112 | "Unable to expand inode %lu. Delete" |
5113 | " some EAs or run e2fsck.", | |
5114 | inode->i_ino); | |
c1bddad9 AK |
5115 | mnt_count = |
5116 | le16_to_cpu(sbi->s_es->s_mnt_count); | |
6dd4ee7c KS |
5117 | } |
5118 | } | |
5119 | } | |
5120 | } | |
ac27a0ec | 5121 | if (!err) |
617ba13b | 5122 | err = ext4_mark_iloc_dirty(handle, inode, &iloc); |
ac27a0ec DK |
5123 | return err; |
5124 | } | |
5125 | ||
5126 | /* | |
617ba13b | 5127 | * ext4_dirty_inode() is called from __mark_inode_dirty() |
ac27a0ec DK |
5128 | * |
5129 | * We're really interested in the case where a file is being extended. | |
5130 | * i_size has been changed by generic_commit_write() and we thus need | |
5131 | * to include the updated inode in the current transaction. | |
5132 | * | |
a269eb18 | 5133 | * Also, vfs_dq_alloc_block() will always dirty the inode when blocks |
ac27a0ec DK |
5134 | * are allocated to the file. |
5135 | * | |
5136 | * If the inode is marked synchronous, we don't honour that here - doing | |
5137 | * so would cause a commit on atime updates, which we don't bother doing. | |
5138 | * We handle synchronous inodes at the highest possible level. | |
5139 | */ | |
617ba13b | 5140 | void ext4_dirty_inode(struct inode *inode) |
ac27a0ec | 5141 | { |
617ba13b | 5142 | handle_t *current_handle = ext4_journal_current_handle(); |
ac27a0ec DK |
5143 | handle_t *handle; |
5144 | ||
0390131b FM |
5145 | if (!ext4_handle_valid(current_handle)) { |
5146 | ext4_mark_inode_dirty(current_handle, inode); | |
5147 | return; | |
5148 | } | |
5149 | ||
617ba13b | 5150 | handle = ext4_journal_start(inode, 2); |
ac27a0ec DK |
5151 | if (IS_ERR(handle)) |
5152 | goto out; | |
5153 | if (current_handle && | |
5154 | current_handle->h_transaction != handle->h_transaction) { | |
5155 | /* This task has a transaction open against a different fs */ | |
5156 | printk(KERN_EMERG "%s: transactions do not match!\n", | |
46e665e9 | 5157 | __func__); |
ac27a0ec DK |
5158 | } else { |
5159 | jbd_debug(5, "marking dirty. outer handle=%p\n", | |
5160 | current_handle); | |
617ba13b | 5161 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec | 5162 | } |
617ba13b | 5163 | ext4_journal_stop(handle); |
ac27a0ec DK |
5164 | out: |
5165 | return; | |
5166 | } | |
5167 | ||
5168 | #if 0 | |
5169 | /* | |
5170 | * Bind an inode's backing buffer_head into this transaction, to prevent | |
5171 | * it from being flushed to disk early. Unlike | |
617ba13b | 5172 | * ext4_reserve_inode_write, this leaves behind no bh reference and |
ac27a0ec DK |
5173 | * returns no iloc structure, so the caller needs to repeat the iloc |
5174 | * lookup to mark the inode dirty later. | |
5175 | */ | |
617ba13b | 5176 | static int ext4_pin_inode(handle_t *handle, struct inode *inode) |
ac27a0ec | 5177 | { |
617ba13b | 5178 | struct ext4_iloc iloc; |
ac27a0ec DK |
5179 | |
5180 | int err = 0; | |
5181 | if (handle) { | |
617ba13b | 5182 | err = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
5183 | if (!err) { |
5184 | BUFFER_TRACE(iloc.bh, "get_write_access"); | |
dab291af | 5185 | err = jbd2_journal_get_write_access(handle, iloc.bh); |
ac27a0ec | 5186 | if (!err) |
0390131b FM |
5187 | err = ext4_handle_dirty_metadata(handle, |
5188 | inode, | |
5189 | iloc.bh); | |
ac27a0ec DK |
5190 | brelse(iloc.bh); |
5191 | } | |
5192 | } | |
617ba13b | 5193 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5194 | return err; |
5195 | } | |
5196 | #endif | |
5197 | ||
617ba13b | 5198 | int ext4_change_inode_journal_flag(struct inode *inode, int val) |
ac27a0ec DK |
5199 | { |
5200 | journal_t *journal; | |
5201 | handle_t *handle; | |
5202 | int err; | |
5203 | ||
5204 | /* | |
5205 | * We have to be very careful here: changing a data block's | |
5206 | * journaling status dynamically is dangerous. If we write a | |
5207 | * data block to the journal, change the status and then delete | |
5208 | * that block, we risk forgetting to revoke the old log record | |
5209 | * from the journal and so a subsequent replay can corrupt data. | |
5210 | * So, first we make sure that the journal is empty and that | |
5211 | * nobody is changing anything. | |
5212 | */ | |
5213 | ||
617ba13b | 5214 | journal = EXT4_JOURNAL(inode); |
0390131b FM |
5215 | if (!journal) |
5216 | return 0; | |
d699594d | 5217 | if (is_journal_aborted(journal)) |
ac27a0ec DK |
5218 | return -EROFS; |
5219 | ||
dab291af MC |
5220 | jbd2_journal_lock_updates(journal); |
5221 | jbd2_journal_flush(journal); | |
ac27a0ec DK |
5222 | |
5223 | /* | |
5224 | * OK, there are no updates running now, and all cached data is | |
5225 | * synced to disk. We are now in a completely consistent state | |
5226 | * which doesn't have anything in the journal, and we know that | |
5227 | * no filesystem updates are running, so it is safe to modify | |
5228 | * the inode's in-core data-journaling state flag now. | |
5229 | */ | |
5230 | ||
5231 | if (val) | |
617ba13b | 5232 | EXT4_I(inode)->i_flags |= EXT4_JOURNAL_DATA_FL; |
ac27a0ec | 5233 | else |
617ba13b MC |
5234 | EXT4_I(inode)->i_flags &= ~EXT4_JOURNAL_DATA_FL; |
5235 | ext4_set_aops(inode); | |
ac27a0ec | 5236 | |
dab291af | 5237 | jbd2_journal_unlock_updates(journal); |
ac27a0ec DK |
5238 | |
5239 | /* Finally we can mark the inode as dirty. */ | |
5240 | ||
617ba13b | 5241 | handle = ext4_journal_start(inode, 1); |
ac27a0ec DK |
5242 | if (IS_ERR(handle)) |
5243 | return PTR_ERR(handle); | |
5244 | ||
617ba13b | 5245 | err = ext4_mark_inode_dirty(handle, inode); |
0390131b | 5246 | ext4_handle_sync(handle); |
617ba13b MC |
5247 | ext4_journal_stop(handle); |
5248 | ext4_std_error(inode->i_sb, err); | |
ac27a0ec DK |
5249 | |
5250 | return err; | |
5251 | } | |
2e9ee850 AK |
5252 | |
5253 | static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh) | |
5254 | { | |
5255 | return !buffer_mapped(bh); | |
5256 | } | |
5257 | ||
c2ec175c | 5258 | int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
2e9ee850 | 5259 | { |
c2ec175c | 5260 | struct page *page = vmf->page; |
2e9ee850 AK |
5261 | loff_t size; |
5262 | unsigned long len; | |
5263 | int ret = -EINVAL; | |
79f0be8d | 5264 | void *fsdata; |
2e9ee850 AK |
5265 | struct file *file = vma->vm_file; |
5266 | struct inode *inode = file->f_path.dentry->d_inode; | |
5267 | struct address_space *mapping = inode->i_mapping; | |
5268 | ||
5269 | /* | |
5270 | * Get i_alloc_sem to stop truncates messing with the inode. We cannot | |
5271 | * get i_mutex because we are already holding mmap_sem. | |
5272 | */ | |
5273 | down_read(&inode->i_alloc_sem); | |
5274 | size = i_size_read(inode); | |
5275 | if (page->mapping != mapping || size <= page_offset(page) | |
5276 | || !PageUptodate(page)) { | |
5277 | /* page got truncated from under us? */ | |
5278 | goto out_unlock; | |
5279 | } | |
5280 | ret = 0; | |
5281 | if (PageMappedToDisk(page)) | |
5282 | goto out_unlock; | |
5283 | ||
5284 | if (page->index == size >> PAGE_CACHE_SHIFT) | |
5285 | len = size & ~PAGE_CACHE_MASK; | |
5286 | else | |
5287 | len = PAGE_CACHE_SIZE; | |
5288 | ||
5289 | if (page_has_buffers(page)) { | |
5290 | /* return if we have all the buffers mapped */ | |
5291 | if (!walk_page_buffers(NULL, page_buffers(page), 0, len, NULL, | |
5292 | ext4_bh_unmapped)) | |
5293 | goto out_unlock; | |
5294 | } | |
5295 | /* | |
5296 | * OK, we need to fill the hole... Do write_begin write_end | |
5297 | * to do block allocation/reservation.We are not holding | |
5298 | * inode.i__mutex here. That allow * parallel write_begin, | |
5299 | * write_end call. lock_page prevent this from happening | |
5300 | * on the same page though | |
5301 | */ | |
5302 | ret = mapping->a_ops->write_begin(file, mapping, page_offset(page), | |
79f0be8d | 5303 | len, AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata); |
2e9ee850 AK |
5304 | if (ret < 0) |
5305 | goto out_unlock; | |
5306 | ret = mapping->a_ops->write_end(file, mapping, page_offset(page), | |
79f0be8d | 5307 | len, len, page, fsdata); |
2e9ee850 AK |
5308 | if (ret < 0) |
5309 | goto out_unlock; | |
5310 | ret = 0; | |
5311 | out_unlock: | |
c2ec175c NP |
5312 | if (ret) |
5313 | ret = VM_FAULT_SIGBUS; | |
2e9ee850 AK |
5314 | up_read(&inode->i_alloc_sem); |
5315 | return ret; | |
5316 | } |