Commit | Line | Data |
---|---|---|
1ccd14b9 JK |
1 | /* |
2 | * vfsv0 quota IO operations on file | |
3 | */ | |
4 | ||
5 | #include <linux/errno.h> | |
6 | #include <linux/fs.h> | |
7 | #include <linux/mount.h> | |
8 | #include <linux/dqblk_v2.h> | |
9 | #include <linux/kernel.h> | |
10 | #include <linux/init.h> | |
11 | #include <linux/module.h> | |
12 | #include <linux/slab.h> | |
13 | #include <linux/quotaops.h> | |
14 | ||
15 | #include <asm/byteorder.h> | |
16 | ||
17 | #include "quota_tree.h" | |
18 | ||
19 | MODULE_AUTHOR("Jan Kara"); | |
20 | MODULE_DESCRIPTION("Quota trie support"); | |
21 | MODULE_LICENSE("GPL"); | |
22 | ||
23 | #define __QUOTA_QT_PARANOIA | |
24 | ||
25 | typedef char *dqbuf_t; | |
26 | ||
27 | static int get_index(struct qtree_mem_dqinfo *info, qid_t id, int depth) | |
28 | { | |
29 | unsigned int epb = info->dqi_usable_bs >> 2; | |
30 | ||
31 | depth = info->dqi_qtree_depth - depth - 1; | |
32 | while (depth--) | |
33 | id /= epb; | |
34 | return id % epb; | |
35 | } | |
36 | ||
37 | /* Number of entries in one blocks */ | |
38 | static inline int qtree_dqstr_in_blk(struct qtree_mem_dqinfo *info) | |
39 | { | |
40 | return (info->dqi_usable_bs - sizeof(struct qt_disk_dqdbheader)) | |
41 | / info->dqi_entry_size; | |
42 | } | |
43 | ||
44 | static dqbuf_t getdqbuf(size_t size) | |
45 | { | |
46 | dqbuf_t buf = kmalloc(size, GFP_NOFS); | |
47 | if (!buf) | |
48 | printk(KERN_WARNING "VFS: Not enough memory for quota buffers.\n"); | |
49 | return buf; | |
50 | } | |
51 | ||
52 | static inline void freedqbuf(dqbuf_t buf) | |
53 | { | |
54 | kfree(buf); | |
55 | } | |
56 | ||
57 | static inline ssize_t read_blk(struct qtree_mem_dqinfo *info, uint blk, dqbuf_t buf) | |
58 | { | |
59 | struct super_block *sb = info->dqi_sb; | |
60 | ||
61 | memset(buf, 0, info->dqi_usable_bs); | |
62 | return sb->s_op->quota_read(sb, info->dqi_type, (char *)buf, | |
63 | info->dqi_usable_bs, blk << info->dqi_blocksize_bits); | |
64 | } | |
65 | ||
66 | static inline ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, dqbuf_t buf) | |
67 | { | |
68 | struct super_block *sb = info->dqi_sb; | |
69 | ||
70 | return sb->s_op->quota_write(sb, info->dqi_type, (char *)buf, | |
71 | info->dqi_usable_bs, blk << info->dqi_blocksize_bits); | |
72 | } | |
73 | ||
74 | /* Remove empty block from list and return it */ | |
75 | static int get_free_dqblk(struct qtree_mem_dqinfo *info) | |
76 | { | |
77 | dqbuf_t buf = getdqbuf(info->dqi_usable_bs); | |
78 | struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; | |
79 | int ret, blk; | |
80 | ||
81 | if (!buf) | |
82 | return -ENOMEM; | |
83 | if (info->dqi_free_blk) { | |
84 | blk = info->dqi_free_blk; | |
85 | ret = read_blk(info, blk, buf); | |
86 | if (ret < 0) | |
87 | goto out_buf; | |
88 | info->dqi_free_blk = le32_to_cpu(dh->dqdh_next_free); | |
89 | } | |
90 | else { | |
91 | memset(buf, 0, info->dqi_usable_bs); | |
92 | /* Assure block allocation... */ | |
93 | ret = write_blk(info, info->dqi_blocks, buf); | |
94 | if (ret < 0) | |
95 | goto out_buf; | |
96 | blk = info->dqi_blocks++; | |
97 | } | |
98 | mark_info_dirty(info->dqi_sb, info->dqi_type); | |
99 | ret = blk; | |
100 | out_buf: | |
101 | freedqbuf(buf); | |
102 | return ret; | |
103 | } | |
104 | ||
105 | /* Insert empty block to the list */ | |
106 | static int put_free_dqblk(struct qtree_mem_dqinfo *info, dqbuf_t buf, uint blk) | |
107 | { | |
108 | struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; | |
109 | int err; | |
110 | ||
111 | dh->dqdh_next_free = cpu_to_le32(info->dqi_free_blk); | |
112 | dh->dqdh_prev_free = cpu_to_le32(0); | |
113 | dh->dqdh_entries = cpu_to_le16(0); | |
114 | err = write_blk(info, blk, buf); | |
115 | if (err < 0) | |
116 | return err; | |
117 | info->dqi_free_blk = blk; | |
118 | mark_info_dirty(info->dqi_sb, info->dqi_type); | |
119 | return 0; | |
120 | } | |
121 | ||
122 | /* Remove given block from the list of blocks with free entries */ | |
123 | static int remove_free_dqentry(struct qtree_mem_dqinfo *info, dqbuf_t buf, uint blk) | |
124 | { | |
125 | dqbuf_t tmpbuf = getdqbuf(info->dqi_usable_bs); | |
126 | struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; | |
127 | uint nextblk = le32_to_cpu(dh->dqdh_next_free); | |
128 | uint prevblk = le32_to_cpu(dh->dqdh_prev_free); | |
129 | int err; | |
130 | ||
131 | if (!tmpbuf) | |
132 | return -ENOMEM; | |
133 | if (nextblk) { | |
134 | err = read_blk(info, nextblk, tmpbuf); | |
135 | if (err < 0) | |
136 | goto out_buf; | |
137 | ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free = | |
138 | dh->dqdh_prev_free; | |
139 | err = write_blk(info, nextblk, tmpbuf); | |
140 | if (err < 0) | |
141 | goto out_buf; | |
142 | } | |
143 | if (prevblk) { | |
144 | err = read_blk(info, prevblk, tmpbuf); | |
145 | if (err < 0) | |
146 | goto out_buf; | |
147 | ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_next_free = | |
148 | dh->dqdh_next_free; | |
149 | err = write_blk(info, prevblk, tmpbuf); | |
150 | if (err < 0) | |
151 | goto out_buf; | |
152 | } else { | |
153 | info->dqi_free_entry = nextblk; | |
154 | mark_info_dirty(info->dqi_sb, info->dqi_type); | |
155 | } | |
156 | freedqbuf(tmpbuf); | |
157 | dh->dqdh_next_free = dh->dqdh_prev_free = cpu_to_le32(0); | |
158 | /* No matter whether write succeeds block is out of list */ | |
159 | if (write_blk(info, blk, buf) < 0) | |
160 | printk(KERN_ERR "VFS: Can't write block (%u) with free entries.\n", blk); | |
161 | return 0; | |
162 | out_buf: | |
163 | freedqbuf(tmpbuf); | |
164 | return err; | |
165 | } | |
166 | ||
167 | /* Insert given block to the beginning of list with free entries */ | |
168 | static int insert_free_dqentry(struct qtree_mem_dqinfo *info, dqbuf_t buf, uint blk) | |
169 | { | |
170 | dqbuf_t tmpbuf = getdqbuf(info->dqi_usable_bs); | |
171 | struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; | |
172 | int err; | |
173 | ||
174 | if (!tmpbuf) | |
175 | return -ENOMEM; | |
176 | dh->dqdh_next_free = cpu_to_le32(info->dqi_free_entry); | |
177 | dh->dqdh_prev_free = cpu_to_le32(0); | |
178 | err = write_blk(info, blk, buf); | |
179 | if (err < 0) | |
180 | goto out_buf; | |
181 | if (info->dqi_free_entry) { | |
182 | err = read_blk(info, info->dqi_free_entry, tmpbuf); | |
183 | if (err < 0) | |
184 | goto out_buf; | |
185 | ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free = | |
186 | cpu_to_le32(blk); | |
187 | err = write_blk(info, info->dqi_free_entry, tmpbuf); | |
188 | if (err < 0) | |
189 | goto out_buf; | |
190 | } | |
191 | freedqbuf(tmpbuf); | |
192 | info->dqi_free_entry = blk; | |
193 | mark_info_dirty(info->dqi_sb, info->dqi_type); | |
194 | return 0; | |
195 | out_buf: | |
196 | freedqbuf(tmpbuf); | |
197 | return err; | |
198 | } | |
199 | ||
200 | /* Is the entry in the block free? */ | |
201 | int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk) | |
202 | { | |
203 | int i; | |
204 | ||
205 | for (i = 0; i < info->dqi_entry_size; i++) | |
206 | if (disk[i]) | |
207 | return 0; | |
208 | return 1; | |
209 | } | |
210 | EXPORT_SYMBOL(qtree_entry_unused); | |
211 | ||
212 | /* Find space for dquot */ | |
213 | static uint find_free_dqentry(struct qtree_mem_dqinfo *info, | |
214 | struct dquot *dquot, int *err) | |
215 | { | |
216 | uint blk, i; | |
217 | struct qt_disk_dqdbheader *dh; | |
218 | dqbuf_t buf = getdqbuf(info->dqi_usable_bs); | |
219 | char *ddquot; | |
220 | ||
221 | *err = 0; | |
222 | if (!buf) { | |
223 | *err = -ENOMEM; | |
224 | return 0; | |
225 | } | |
226 | dh = (struct qt_disk_dqdbheader *)buf; | |
227 | if (info->dqi_free_entry) { | |
228 | blk = info->dqi_free_entry; | |
229 | *err = read_blk(info, blk, buf); | |
230 | if (*err < 0) | |
231 | goto out_buf; | |
232 | } else { | |
233 | blk = get_free_dqblk(info); | |
234 | if ((int)blk < 0) { | |
235 | *err = blk; | |
236 | freedqbuf(buf); | |
237 | return 0; | |
238 | } | |
239 | memset(buf, 0, info->dqi_usable_bs); | |
240 | /* This is enough as block is already zeroed and entry list is empty... */ | |
241 | info->dqi_free_entry = blk; | |
242 | mark_info_dirty(dquot->dq_sb, dquot->dq_type); | |
243 | } | |
244 | /* Block will be full? */ | |
245 | if (le16_to_cpu(dh->dqdh_entries) + 1 >= qtree_dqstr_in_blk(info)) { | |
246 | *err = remove_free_dqentry(info, buf, blk); | |
247 | if (*err < 0) { | |
248 | printk(KERN_ERR "VFS: find_free_dqentry(): Can't " | |
249 | "remove block (%u) from entry free list.\n", | |
250 | blk); | |
251 | goto out_buf; | |
252 | } | |
253 | } | |
254 | le16_add_cpu(&dh->dqdh_entries, 1); | |
255 | /* Find free structure in block */ | |
256 | for (i = 0, ddquot = ((char *)buf) + sizeof(struct qt_disk_dqdbheader); | |
257 | i < qtree_dqstr_in_blk(info) && !qtree_entry_unused(info, ddquot); | |
258 | i++, ddquot += info->dqi_entry_size); | |
259 | #ifdef __QUOTA_QT_PARANOIA | |
260 | if (i == qtree_dqstr_in_blk(info)) { | |
261 | printk(KERN_ERR "VFS: find_free_dqentry(): Data block full " | |
262 | "but it shouldn't.\n"); | |
263 | *err = -EIO; | |
264 | goto out_buf; | |
265 | } | |
266 | #endif | |
267 | *err = write_blk(info, blk, buf); | |
268 | if (*err < 0) { | |
269 | printk(KERN_ERR "VFS: find_free_dqentry(): Can't write quota " | |
270 | "data block %u.\n", blk); | |
271 | goto out_buf; | |
272 | } | |
273 | dquot->dq_off = (blk << info->dqi_blocksize_bits) + | |
274 | sizeof(struct qt_disk_dqdbheader) + | |
275 | i * info->dqi_entry_size; | |
276 | freedqbuf(buf); | |
277 | return blk; | |
278 | out_buf: | |
279 | freedqbuf(buf); | |
280 | return 0; | |
281 | } | |
282 | ||
283 | /* Insert reference to structure into the trie */ | |
284 | static int do_insert_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot, | |
285 | uint *treeblk, int depth) | |
286 | { | |
287 | dqbuf_t buf = getdqbuf(info->dqi_usable_bs); | |
288 | int ret = 0, newson = 0, newact = 0; | |
289 | __le32 *ref; | |
290 | uint newblk; | |
291 | ||
292 | if (!buf) | |
293 | return -ENOMEM; | |
294 | if (!*treeblk) { | |
295 | ret = get_free_dqblk(info); | |
296 | if (ret < 0) | |
297 | goto out_buf; | |
298 | *treeblk = ret; | |
299 | memset(buf, 0, info->dqi_usable_bs); | |
300 | newact = 1; | |
301 | } else { | |
302 | ret = read_blk(info, *treeblk, buf); | |
303 | if (ret < 0) { | |
304 | printk(KERN_ERR "VFS: Can't read tree quota block " | |
305 | "%u.\n", *treeblk); | |
306 | goto out_buf; | |
307 | } | |
308 | } | |
309 | ref = (__le32 *)buf; | |
310 | newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); | |
311 | if (!newblk) | |
312 | newson = 1; | |
313 | if (depth == info->dqi_qtree_depth - 1) { | |
314 | #ifdef __QUOTA_QT_PARANOIA | |
315 | if (newblk) { | |
316 | printk(KERN_ERR "VFS: Inserting already present quota " | |
317 | "entry (block %u).\n", | |
318 | le32_to_cpu(ref[get_index(info, | |
319 | dquot->dq_id, depth)])); | |
320 | ret = -EIO; | |
321 | goto out_buf; | |
322 | } | |
323 | #endif | |
324 | newblk = find_free_dqentry(info, dquot, &ret); | |
325 | } else { | |
326 | ret = do_insert_tree(info, dquot, &newblk, depth+1); | |
327 | } | |
328 | if (newson && ret >= 0) { | |
329 | ref[get_index(info, dquot->dq_id, depth)] = | |
330 | cpu_to_le32(newblk); | |
331 | ret = write_blk(info, *treeblk, buf); | |
332 | } else if (newact && ret < 0) { | |
333 | put_free_dqblk(info, buf, *treeblk); | |
334 | } | |
335 | out_buf: | |
336 | freedqbuf(buf); | |
337 | return ret; | |
338 | } | |
339 | ||
340 | /* Wrapper for inserting quota structure into tree */ | |
341 | static inline int dq_insert_tree(struct qtree_mem_dqinfo *info, | |
342 | struct dquot *dquot) | |
343 | { | |
344 | int tmp = QT_TREEOFF; | |
345 | return do_insert_tree(info, dquot, &tmp, 0); | |
346 | } | |
347 | ||
348 | /* | |
349 | * We don't have to be afraid of deadlocks as we never have quotas on quota files... | |
350 | */ | |
351 | int qtree_write_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) | |
352 | { | |
353 | int type = dquot->dq_type; | |
354 | struct super_block *sb = dquot->dq_sb; | |
355 | ssize_t ret; | |
356 | dqbuf_t ddquot = getdqbuf(info->dqi_entry_size); | |
357 | ||
358 | if (!ddquot) | |
359 | return -ENOMEM; | |
360 | ||
361 | /* dq_off is guarded by dqio_mutex */ | |
362 | if (!dquot->dq_off) { | |
363 | ret = dq_insert_tree(info, dquot); | |
364 | if (ret < 0) { | |
365 | printk(KERN_ERR "VFS: Error %zd occurred while " | |
366 | "creating quota.\n", ret); | |
367 | freedqbuf(ddquot); | |
368 | return ret; | |
369 | } | |
370 | } | |
371 | spin_lock(&dq_data_lock); | |
372 | info->dqi_ops->mem2disk_dqblk(ddquot, dquot); | |
373 | spin_unlock(&dq_data_lock); | |
374 | ret = sb->s_op->quota_write(sb, type, (char *)ddquot, | |
375 | info->dqi_entry_size, dquot->dq_off); | |
376 | if (ret != info->dqi_entry_size) { | |
377 | printk(KERN_WARNING "VFS: dquota write failed on dev %s\n", | |
378 | sb->s_id); | |
379 | if (ret >= 0) | |
380 | ret = -ENOSPC; | |
381 | } else { | |
382 | ret = 0; | |
383 | } | |
384 | dqstats.writes++; | |
385 | freedqbuf(ddquot); | |
386 | ||
387 | return ret; | |
388 | } | |
389 | EXPORT_SYMBOL(qtree_write_dquot); | |
390 | ||
391 | /* Free dquot entry in data block */ | |
392 | static int free_dqentry(struct qtree_mem_dqinfo *info, struct dquot *dquot, | |
393 | uint blk) | |
394 | { | |
395 | struct qt_disk_dqdbheader *dh; | |
396 | dqbuf_t buf = getdqbuf(info->dqi_usable_bs); | |
397 | int ret = 0; | |
398 | ||
399 | if (!buf) | |
400 | return -ENOMEM; | |
401 | if (dquot->dq_off >> info->dqi_blocksize_bits != blk) { | |
402 | printk(KERN_ERR "VFS: Quota structure has offset to other " | |
403 | "block (%u) than it should (%u).\n", blk, | |
404 | (uint)(dquot->dq_off >> info->dqi_blocksize_bits)); | |
405 | goto out_buf; | |
406 | } | |
407 | ret = read_blk(info, blk, buf); | |
408 | if (ret < 0) { | |
409 | printk(KERN_ERR "VFS: Can't read quota data block %u\n", blk); | |
410 | goto out_buf; | |
411 | } | |
412 | dh = (struct qt_disk_dqdbheader *)buf; | |
413 | le16_add_cpu(&dh->dqdh_entries, -1); | |
414 | if (!le16_to_cpu(dh->dqdh_entries)) { /* Block got free? */ | |
415 | ret = remove_free_dqentry(info, buf, blk); | |
416 | if (ret >= 0) | |
417 | ret = put_free_dqblk(info, buf, blk); | |
418 | if (ret < 0) { | |
419 | printk(KERN_ERR "VFS: Can't move quota data block (%u) " | |
420 | "to free list.\n", blk); | |
421 | goto out_buf; | |
422 | } | |
423 | } else { | |
424 | memset(buf + | |
425 | (dquot->dq_off & ((1 << info->dqi_blocksize_bits) - 1)), | |
426 | 0, info->dqi_entry_size); | |
427 | if (le16_to_cpu(dh->dqdh_entries) == | |
428 | qtree_dqstr_in_blk(info) - 1) { | |
429 | /* Insert will write block itself */ | |
430 | ret = insert_free_dqentry(info, buf, blk); | |
431 | if (ret < 0) { | |
432 | printk(KERN_ERR "VFS: Can't insert quota data " | |
433 | "block (%u) to free entry list.\n", blk); | |
434 | goto out_buf; | |
435 | } | |
436 | } else { | |
437 | ret = write_blk(info, blk, buf); | |
438 | if (ret < 0) { | |
439 | printk(KERN_ERR "VFS: Can't write quota data " | |
440 | "block %u\n", blk); | |
441 | goto out_buf; | |
442 | } | |
443 | } | |
444 | } | |
445 | dquot->dq_off = 0; /* Quota is now unattached */ | |
446 | out_buf: | |
447 | freedqbuf(buf); | |
448 | return ret; | |
449 | } | |
450 | ||
451 | /* Remove reference to dquot from tree */ | |
452 | static int remove_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot, | |
453 | uint *blk, int depth) | |
454 | { | |
455 | dqbuf_t buf = getdqbuf(info->dqi_usable_bs); | |
456 | int ret = 0; | |
457 | uint newblk; | |
458 | __le32 *ref = (__le32 *)buf; | |
459 | ||
460 | if (!buf) | |
461 | return -ENOMEM; | |
462 | ret = read_blk(info, *blk, buf); | |
463 | if (ret < 0) { | |
464 | printk(KERN_ERR "VFS: Can't read quota data block %u\n", *blk); | |
465 | goto out_buf; | |
466 | } | |
467 | newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); | |
468 | if (depth == info->dqi_qtree_depth - 1) { | |
469 | ret = free_dqentry(info, dquot, newblk); | |
470 | newblk = 0; | |
471 | } else { | |
472 | ret = remove_tree(info, dquot, &newblk, depth+1); | |
473 | } | |
474 | if (ret >= 0 && !newblk) { | |
475 | int i; | |
476 | ref[get_index(info, dquot->dq_id, depth)] = cpu_to_le32(0); | |
477 | /* Block got empty? */ | |
478 | for (i = 0; | |
479 | i < (info->dqi_usable_bs >> 2) && !ref[i]; | |
480 | i++); | |
481 | /* Don't put the root block into the free block list */ | |
482 | if (i == (info->dqi_usable_bs >> 2) | |
483 | && *blk != QT_TREEOFF) { | |
484 | put_free_dqblk(info, buf, *blk); | |
485 | *blk = 0; | |
486 | } else { | |
487 | ret = write_blk(info, *blk, buf); | |
488 | if (ret < 0) | |
489 | printk(KERN_ERR "VFS: Can't write quota tree " | |
490 | "block %u.\n", *blk); | |
491 | } | |
492 | } | |
493 | out_buf: | |
494 | freedqbuf(buf); | |
495 | return ret; | |
496 | } | |
497 | ||
498 | /* Delete dquot from tree */ | |
499 | int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) | |
500 | { | |
501 | uint tmp = QT_TREEOFF; | |
502 | ||
503 | if (!dquot->dq_off) /* Even not allocated? */ | |
504 | return 0; | |
505 | return remove_tree(info, dquot, &tmp, 0); | |
506 | } | |
507 | EXPORT_SYMBOL(qtree_delete_dquot); | |
508 | ||
509 | /* Find entry in block */ | |
510 | static loff_t find_block_dqentry(struct qtree_mem_dqinfo *info, | |
511 | struct dquot *dquot, uint blk) | |
512 | { | |
513 | dqbuf_t buf = getdqbuf(info->dqi_usable_bs); | |
514 | loff_t ret = 0; | |
515 | int i; | |
516 | char *ddquot; | |
517 | ||
518 | if (!buf) | |
519 | return -ENOMEM; | |
520 | ret = read_blk(info, blk, buf); | |
521 | if (ret < 0) { | |
522 | printk(KERN_ERR "VFS: Can't read quota tree block %u.\n", blk); | |
523 | goto out_buf; | |
524 | } | |
525 | for (i = 0, ddquot = ((char *)buf) + sizeof(struct qt_disk_dqdbheader); | |
526 | i < qtree_dqstr_in_blk(info) && !info->dqi_ops->is_id(ddquot, dquot); | |
527 | i++, ddquot += info->dqi_entry_size); | |
528 | if (i == qtree_dqstr_in_blk(info)) { | |
529 | printk(KERN_ERR "VFS: Quota for id %u referenced " | |
530 | "but not present.\n", dquot->dq_id); | |
531 | ret = -EIO; | |
532 | goto out_buf; | |
533 | } else { | |
534 | ret = (blk << info->dqi_blocksize_bits) + sizeof(struct | |
535 | qt_disk_dqdbheader) + i * info->dqi_entry_size; | |
536 | } | |
537 | out_buf: | |
538 | freedqbuf(buf); | |
539 | return ret; | |
540 | } | |
541 | ||
542 | /* Find entry for given id in the tree */ | |
543 | static loff_t find_tree_dqentry(struct qtree_mem_dqinfo *info, | |
544 | struct dquot *dquot, uint blk, int depth) | |
545 | { | |
546 | dqbuf_t buf = getdqbuf(info->dqi_usable_bs); | |
547 | loff_t ret = 0; | |
548 | __le32 *ref = (__le32 *)buf; | |
549 | ||
550 | if (!buf) | |
551 | return -ENOMEM; | |
552 | ret = read_blk(info, blk, buf); | |
553 | if (ret < 0) { | |
554 | printk(KERN_ERR "VFS: Can't read quota tree block %u.\n", blk); | |
555 | goto out_buf; | |
556 | } | |
557 | ret = 0; | |
558 | blk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); | |
559 | if (!blk) /* No reference? */ | |
560 | goto out_buf; | |
561 | if (depth < info->dqi_qtree_depth - 1) | |
562 | ret = find_tree_dqentry(info, dquot, blk, depth+1); | |
563 | else | |
564 | ret = find_block_dqentry(info, dquot, blk); | |
565 | out_buf: | |
566 | freedqbuf(buf); | |
567 | return ret; | |
568 | } | |
569 | ||
570 | /* Find entry for given id in the tree - wrapper function */ | |
571 | static inline loff_t find_dqentry(struct qtree_mem_dqinfo *info, | |
572 | struct dquot *dquot) | |
573 | { | |
574 | return find_tree_dqentry(info, dquot, QT_TREEOFF, 0); | |
575 | } | |
576 | ||
577 | int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) | |
578 | { | |
579 | int type = dquot->dq_type; | |
580 | struct super_block *sb = dquot->dq_sb; | |
581 | loff_t offset; | |
582 | dqbuf_t ddquot; | |
583 | int ret = 0; | |
584 | ||
585 | #ifdef __QUOTA_QT_PARANOIA | |
586 | /* Invalidated quota? */ | |
587 | if (!sb_dqopt(dquot->dq_sb)->files[type]) { | |
588 | printk(KERN_ERR "VFS: Quota invalidated while reading!\n"); | |
589 | return -EIO; | |
590 | } | |
591 | #endif | |
592 | /* Do we know offset of the dquot entry in the quota file? */ | |
593 | if (!dquot->dq_off) { | |
594 | offset = find_dqentry(info, dquot); | |
595 | if (offset <= 0) { /* Entry not present? */ | |
596 | if (offset < 0) | |
597 | printk(KERN_ERR "VFS: Can't read quota " | |
598 | "structure for id %u.\n", dquot->dq_id); | |
599 | dquot->dq_off = 0; | |
600 | set_bit(DQ_FAKE_B, &dquot->dq_flags); | |
601 | memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk)); | |
602 | ret = offset; | |
603 | goto out; | |
604 | } | |
605 | dquot->dq_off = offset; | |
606 | } | |
607 | ddquot = getdqbuf(info->dqi_entry_size); | |
608 | if (!ddquot) | |
609 | return -ENOMEM; | |
610 | ret = sb->s_op->quota_read(sb, type, (char *)ddquot, | |
611 | info->dqi_entry_size, dquot->dq_off); | |
612 | if (ret != info->dqi_entry_size) { | |
613 | if (ret >= 0) | |
614 | ret = -EIO; | |
615 | printk(KERN_ERR "VFS: Error while reading quota " | |
616 | "structure for id %u.\n", dquot->dq_id); | |
617 | set_bit(DQ_FAKE_B, &dquot->dq_flags); | |
618 | memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk)); | |
619 | freedqbuf(ddquot); | |
620 | goto out; | |
621 | } | |
622 | spin_lock(&dq_data_lock); | |
623 | info->dqi_ops->disk2mem_dqblk(dquot, ddquot); | |
624 | if (!dquot->dq_dqb.dqb_bhardlimit && | |
625 | !dquot->dq_dqb.dqb_bsoftlimit && | |
626 | !dquot->dq_dqb.dqb_ihardlimit && | |
627 | !dquot->dq_dqb.dqb_isoftlimit) | |
628 | set_bit(DQ_FAKE_B, &dquot->dq_flags); | |
629 | spin_unlock(&dq_data_lock); | |
630 | freedqbuf(ddquot); | |
631 | out: | |
632 | dqstats.reads++; | |
633 | return ret; | |
634 | } | |
635 | EXPORT_SYMBOL(qtree_read_dquot); | |
636 | ||
637 | /* Check whether dquot should not be deleted. We know we are | |
638 | * the only one operating on dquot (thanks to dq_lock) */ | |
639 | int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) | |
640 | { | |
641 | if (test_bit(DQ_FAKE_B, &dquot->dq_flags) && !(dquot->dq_dqb.dqb_curinodes | dquot->dq_dqb.dqb_curspace)) | |
642 | return qtree_delete_dquot(info, dquot); | |
643 | return 0; | |
644 | } | |
645 | EXPORT_SYMBOL(qtree_release_dquot); |