Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/fs/dquot.c
Parent Directory | Revision Log
Revision 630 -
(show annotations)
(download)
Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
File MIME type: text/plain
File size: 52865 byte(s)
Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
File MIME type: text/plain
File size: 52865 byte(s)
Tag kernel26-2.6.12-alx-r9
1 | /* |
2 | * Implementation of the diskquota system for the LINUX operating system. QUOTA |
3 | * is implemented using the BSD system call interface as the means of |
4 | * communication with the user level. This file contains the generic routines |
5 | * called by the different filesystems on allocation of an inode or block. |
6 | * These routines take care of the administration needed to have a consistent |
7 | * diskquota tracking system. The ideas of both user and group quotas are based |
8 | * on the Melbourne quota system as used on BSD derived systems. The internal |
9 | * implementation is based on one of the several variants of the LINUX |
10 | * inode-subsystem with added complexity of the diskquota system. |
11 | * |
12 | * Version: $Id: dquot.c,v 6.3 1996/11/17 18:35:34 mvw Exp mvw $ |
13 | * |
14 | * Author: Marco van Wieringen <mvw@planets.elm.net> |
15 | * |
16 | * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96 |
17 | * |
18 | * Revised list management to avoid races |
19 | * -- Bill Hawes, <whawes@star.net>, 9/98 |
20 | * |
21 | * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...(). |
22 | * As the consequence the locking was moved from dquot_decr_...(), |
23 | * dquot_incr_...() to calling functions. |
24 | * invalidate_dquots() now writes modified dquots. |
25 | * Serialized quota_off() and quota_on() for mount point. |
26 | * Fixed a few bugs in grow_dquots(). |
27 | * Fixed deadlock in write_dquot() - we no longer account quotas on |
28 | * quota files |
29 | * remove_dquot_ref() moved to inode.c - it now traverses through inodes |
30 | * add_dquot_ref() restarts after blocking |
31 | * Added check for bogus uid and fixed check for group in quotactl. |
32 | * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99 |
33 | * |
34 | * Used struct list_head instead of own list struct |
35 | * Invalidation of referenced dquots is no longer possible |
36 | * Improved free_dquots list management |
37 | * Quota and i_blocks are now updated in one place to avoid races |
38 | * Warnings are now delayed so we won't block in critical section |
39 | * Write updated not to require dquot lock |
40 | * Jan Kara, <jack@suse.cz>, 9/2000 |
41 | * |
42 | * Added dynamic quota structure allocation |
43 | * Jan Kara <jack@suse.cz> 12/2000 |
44 | * |
45 | * Rewritten quota interface. Implemented new quota format and |
46 | * formats registering. |
47 | * Jan Kara, <jack@suse.cz>, 2001,2002 |
48 | * |
49 | * New SMP locking. |
50 | * Jan Kara, <jack@suse.cz>, 10/2002 |
51 | * |
52 | * Added journalled quota support, fix lock inversion problems |
53 | * Jan Kara, <jack@suse.cz>, 2003,2004 |
54 | * |
55 | * (C) Copyright 1994 - 1997 Marco van Wieringen |
56 | */ |
57 | |
58 | #include <linux/errno.h> |
59 | #include <linux/kernel.h> |
60 | #include <linux/fs.h> |
61 | #include <linux/mount.h> |
62 | #include <linux/mm.h> |
63 | #include <linux/time.h> |
64 | #include <linux/types.h> |
65 | #include <linux/string.h> |
66 | #include <linux/fcntl.h> |
67 | #include <linux/stat.h> |
68 | #include <linux/tty.h> |
69 | #include <linux/file.h> |
70 | #include <linux/slab.h> |
71 | #include <linux/sysctl.h> |
72 | #include <linux/smp_lock.h> |
73 | #include <linux/init.h> |
74 | #include <linux/module.h> |
75 | #include <linux/proc_fs.h> |
76 | #include <linux/security.h> |
77 | #include <linux/kmod.h> |
78 | #include <linux/namei.h> |
79 | #include <linux/buffer_head.h> |
80 | |
81 | #include <asm/uaccess.h> |
82 | |
83 | #define __DQUOT_PARANOIA |
84 | |
85 | /* |
86 | * There are two quota SMP locks. dq_list_lock protects all lists with quotas |
87 | * and quota formats and also dqstats structure containing statistics about the |
88 | * lists. dq_data_lock protects data from dq_dqb and also mem_dqinfo structures |
89 | * and also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes. |
90 | * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly |
91 | * in inode_add_bytes() and inode_sub_bytes(). |
92 | * |
93 | * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock |
94 | * |
95 | * Note that some things (eg. sb pointer, type, id) doesn't change during |
96 | * the life of the dquot structure and so needn't to be protected by a lock |
97 | * |
98 | * Any operation working on dquots via inode pointers must hold dqptr_sem. If |
99 | * operation is just reading pointers from inode (or not using them at all) the |
100 | * read lock is enough. If pointers are altered function must hold write lock |
101 | * (these locking rules also apply for S_NOQUOTA flag in the inode - note that |
102 | * for altering the flag i_sem is also needed). If operation is holding |
103 | * reference to dquot in other way (e.g. quotactl ops) it must be guarded by |
104 | * dqonoff_sem. |
105 | * This locking assures that: |
106 | * a) update/access to dquot pointers in inode is serialized |
107 | * b) everyone is guarded against invalidate_dquots() |
108 | * |
109 | * Each dquot has its dq_lock semaphore. Locked dquots might not be referenced |
110 | * from inodes (dquot_alloc_space() and such don't check the dq_lock). |
111 | * Currently dquot is locked only when it is being read to memory (or space for |
112 | * it is being allocated) on the first dqget() and when it is being released on |
113 | * the last dqput(). The allocation and release oparations are serialized by |
114 | * the dq_lock and by checking the use count in dquot_release(). Write |
115 | * operations on dquots don't hold dq_lock as they copy data under dq_data_lock |
116 | * spinlock to internal buffers before writing. |
117 | * |
118 | * Lock ordering (including related VFS locks) is the following: |
119 | * i_sem > dqonoff_sem > iprune_sem > journal_lock > dqptr_sem > |
120 | * > dquot->dq_lock > dqio_sem |
121 | * i_sem on quota files is special (it's below dqio_sem) |
122 | */ |
123 | |
124 | static DEFINE_SPINLOCK(dq_list_lock); |
125 | DEFINE_SPINLOCK(dq_data_lock); |
126 | |
127 | static char *quotatypes[] = INITQFNAMES; |
128 | static struct quota_format_type *quota_formats; /* List of registered formats */ |
129 | static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES; |
130 | |
131 | /* SLAB cache for dquot structures */ |
132 | static kmem_cache_t *dquot_cachep; |
133 | |
134 | int register_quota_format(struct quota_format_type *fmt) |
135 | { |
136 | spin_lock(&dq_list_lock); |
137 | fmt->qf_next = quota_formats; |
138 | quota_formats = fmt; |
139 | spin_unlock(&dq_list_lock); |
140 | return 0; |
141 | } |
142 | |
143 | void unregister_quota_format(struct quota_format_type *fmt) |
144 | { |
145 | struct quota_format_type **actqf; |
146 | |
147 | spin_lock(&dq_list_lock); |
148 | for (actqf = "a_formats; *actqf && *actqf != fmt; actqf = &(*actqf)->qf_next); |
149 | if (*actqf) |
150 | *actqf = (*actqf)->qf_next; |
151 | spin_unlock(&dq_list_lock); |
152 | } |
153 | |
154 | static struct quota_format_type *find_quota_format(int id) |
155 | { |
156 | struct quota_format_type *actqf; |
157 | |
158 | spin_lock(&dq_list_lock); |
159 | for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next); |
160 | if (!actqf || !try_module_get(actqf->qf_owner)) { |
161 | int qm; |
162 | |
163 | spin_unlock(&dq_list_lock); |
164 | |
165 | for (qm = 0; module_names[qm].qm_fmt_id && module_names[qm].qm_fmt_id != id; qm++); |
166 | if (!module_names[qm].qm_fmt_id || request_module(module_names[qm].qm_mod_name)) |
167 | return NULL; |
168 | |
169 | spin_lock(&dq_list_lock); |
170 | for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next); |
171 | if (actqf && !try_module_get(actqf->qf_owner)) |
172 | actqf = NULL; |
173 | } |
174 | spin_unlock(&dq_list_lock); |
175 | return actqf; |
176 | } |
177 | |
178 | static void put_quota_format(struct quota_format_type *fmt) |
179 | { |
180 | module_put(fmt->qf_owner); |
181 | } |
182 | |
183 | /* |
184 | * Dquot List Management: |
185 | * The quota code uses three lists for dquot management: the inuse_list, |
186 | * free_dquots, and dquot_hash[] array. A single dquot structure may be |
187 | * on all three lists, depending on its current state. |
188 | * |
189 | * All dquots are placed to the end of inuse_list when first created, and this |
190 | * list is used for invalidate operation, which must look at every dquot. |
191 | * |
192 | * Unused dquots (dq_count == 0) are added to the free_dquots list when freed, |
193 | * and this list is searched whenever we need an available dquot. Dquots are |
194 | * removed from the list as soon as they are used again, and |
195 | * dqstats.free_dquots gives the number of dquots on the list. When |
196 | * dquot is invalidated it's completely released from memory. |
197 | * |
198 | * Dquots with a specific identity (device, type and id) are placed on |
199 | * one of the dquot_hash[] hash chains. The provides an efficient search |
200 | * mechanism to locate a specific dquot. |
201 | */ |
202 | |
203 | static LIST_HEAD(inuse_list); |
204 | static LIST_HEAD(free_dquots); |
205 | static unsigned int dq_hash_bits, dq_hash_mask; |
206 | static struct hlist_head *dquot_hash; |
207 | |
208 | struct dqstats dqstats; |
209 | |
210 | static void dqput(struct dquot *dquot); |
211 | |
212 | static inline unsigned int |
213 | hashfn(const struct super_block *sb, unsigned int id, int type) |
214 | { |
215 | unsigned long tmp; |
216 | |
217 | tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type); |
218 | return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask; |
219 | } |
220 | |
221 | /* |
222 | * Following list functions expect dq_list_lock to be held |
223 | */ |
224 | static inline void insert_dquot_hash(struct dquot *dquot) |
225 | { |
226 | struct hlist_head *head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type); |
227 | hlist_add_head(&dquot->dq_hash, head); |
228 | } |
229 | |
230 | static inline void remove_dquot_hash(struct dquot *dquot) |
231 | { |
232 | hlist_del_init(&dquot->dq_hash); |
233 | } |
234 | |
235 | static inline struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, unsigned int id, int type) |
236 | { |
237 | struct hlist_node *node; |
238 | struct dquot *dquot; |
239 | |
240 | hlist_for_each (node, dquot_hash+hashent) { |
241 | dquot = hlist_entry(node, struct dquot, dq_hash); |
242 | if (dquot->dq_sb == sb && dquot->dq_id == id && dquot->dq_type == type) |
243 | return dquot; |
244 | } |
245 | return NODQUOT; |
246 | } |
247 | |
248 | /* Add a dquot to the tail of the free list */ |
249 | static inline void put_dquot_last(struct dquot *dquot) |
250 | { |
251 | list_add(&dquot->dq_free, free_dquots.prev); |
252 | dqstats.free_dquots++; |
253 | } |
254 | |
255 | static inline void remove_free_dquot(struct dquot *dquot) |
256 | { |
257 | if (list_empty(&dquot->dq_free)) |
258 | return; |
259 | list_del_init(&dquot->dq_free); |
260 | dqstats.free_dquots--; |
261 | } |
262 | |
263 | static inline void put_inuse(struct dquot *dquot) |
264 | { |
265 | /* We add to the back of inuse list so we don't have to restart |
266 | * when traversing this list and we block */ |
267 | list_add(&dquot->dq_inuse, inuse_list.prev); |
268 | dqstats.allocated_dquots++; |
269 | } |
270 | |
271 | static inline void remove_inuse(struct dquot *dquot) |
272 | { |
273 | dqstats.allocated_dquots--; |
274 | list_del(&dquot->dq_inuse); |
275 | } |
276 | /* |
277 | * End of list functions needing dq_list_lock |
278 | */ |
279 | |
280 | static void wait_on_dquot(struct dquot *dquot) |
281 | { |
282 | down(&dquot->dq_lock); |
283 | up(&dquot->dq_lock); |
284 | } |
285 | |
286 | #define mark_dquot_dirty(dquot) ((dquot)->dq_sb->dq_op->mark_dirty(dquot)) |
287 | |
288 | int dquot_mark_dquot_dirty(struct dquot *dquot) |
289 | { |
290 | spin_lock(&dq_list_lock); |
291 | if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) |
292 | list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)-> |
293 | info[dquot->dq_type].dqi_dirty_list); |
294 | spin_unlock(&dq_list_lock); |
295 | return 0; |
296 | } |
297 | |
298 | /* This function needs dq_list_lock */ |
299 | static inline int clear_dquot_dirty(struct dquot *dquot) |
300 | { |
301 | if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) |
302 | return 0; |
303 | list_del_init(&dquot->dq_dirty); |
304 | return 1; |
305 | } |
306 | |
307 | void mark_info_dirty(struct super_block *sb, int type) |
308 | { |
309 | set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags); |
310 | } |
311 | EXPORT_SYMBOL(mark_info_dirty); |
312 | |
313 | /* |
314 | * Read dquot from disk and alloc space for it |
315 | */ |
316 | |
317 | int dquot_acquire(struct dquot *dquot) |
318 | { |
319 | int ret = 0, ret2 = 0; |
320 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); |
321 | |
322 | down(&dquot->dq_lock); |
323 | down(&dqopt->dqio_sem); |
324 | if (!test_bit(DQ_READ_B, &dquot->dq_flags)) |
325 | ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot); |
326 | if (ret < 0) |
327 | goto out_iolock; |
328 | set_bit(DQ_READ_B, &dquot->dq_flags); |
329 | /* Instantiate dquot if needed */ |
330 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) { |
331 | ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); |
332 | /* Write the info if needed */ |
333 | if (info_dirty(&dqopt->info[dquot->dq_type])) |
334 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type); |
335 | if (ret < 0) |
336 | goto out_iolock; |
337 | if (ret2 < 0) { |
338 | ret = ret2; |
339 | goto out_iolock; |
340 | } |
341 | } |
342 | set_bit(DQ_ACTIVE_B, &dquot->dq_flags); |
343 | out_iolock: |
344 | up(&dqopt->dqio_sem); |
345 | up(&dquot->dq_lock); |
346 | return ret; |
347 | } |
348 | |
349 | /* |
350 | * Write dquot to disk |
351 | */ |
352 | int dquot_commit(struct dquot *dquot) |
353 | { |
354 | int ret = 0, ret2 = 0; |
355 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); |
356 | |
357 | down(&dqopt->dqio_sem); |
358 | spin_lock(&dq_list_lock); |
359 | if (!clear_dquot_dirty(dquot)) { |
360 | spin_unlock(&dq_list_lock); |
361 | goto out_sem; |
362 | } |
363 | spin_unlock(&dq_list_lock); |
364 | /* Inactive dquot can be only if there was error during read/init |
365 | * => we have better not writing it */ |
366 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { |
367 | ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); |
368 | if (info_dirty(&dqopt->info[dquot->dq_type])) |
369 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type); |
370 | if (ret >= 0) |
371 | ret = ret2; |
372 | } |
373 | out_sem: |
374 | up(&dqopt->dqio_sem); |
375 | return ret; |
376 | } |
377 | |
378 | /* |
379 | * Release dquot |
380 | */ |
381 | int dquot_release(struct dquot *dquot) |
382 | { |
383 | int ret = 0, ret2 = 0; |
384 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); |
385 | |
386 | down(&dquot->dq_lock); |
387 | /* Check whether we are not racing with some other dqget() */ |
388 | if (atomic_read(&dquot->dq_count) > 1) |
389 | goto out_dqlock; |
390 | down(&dqopt->dqio_sem); |
391 | if (dqopt->ops[dquot->dq_type]->release_dqblk) { |
392 | ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot); |
393 | /* Write the info */ |
394 | if (info_dirty(&dqopt->info[dquot->dq_type])) |
395 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type); |
396 | if (ret >= 0) |
397 | ret = ret2; |
398 | } |
399 | clear_bit(DQ_ACTIVE_B, &dquot->dq_flags); |
400 | up(&dqopt->dqio_sem); |
401 | out_dqlock: |
402 | up(&dquot->dq_lock); |
403 | return ret; |
404 | } |
405 | |
406 | /* Invalidate all dquots on the list. Note that this function is called after |
407 | * quota is disabled and pointers from inodes removed so there cannot be new |
408 | * quota users. Also because we hold dqonoff_sem there can be no quota users |
409 | * for this sb+type at all. */ |
410 | static void invalidate_dquots(struct super_block *sb, int type) |
411 | { |
412 | struct dquot *dquot; |
413 | struct list_head *head; |
414 | |
415 | spin_lock(&dq_list_lock); |
416 | for (head = inuse_list.next; head != &inuse_list;) { |
417 | dquot = list_entry(head, struct dquot, dq_inuse); |
418 | head = head->next; |
419 | if (dquot->dq_sb != sb) |
420 | continue; |
421 | if (dquot->dq_type != type) |
422 | continue; |
423 | #ifdef __DQUOT_PARANOIA |
424 | if (atomic_read(&dquot->dq_count)) |
425 | BUG(); |
426 | #endif |
427 | /* Quota now has no users and it has been written on last dqput() */ |
428 | remove_dquot_hash(dquot); |
429 | remove_free_dquot(dquot); |
430 | remove_inuse(dquot); |
431 | kmem_cache_free(dquot_cachep, dquot); |
432 | } |
433 | spin_unlock(&dq_list_lock); |
434 | } |
435 | |
436 | int vfs_quota_sync(struct super_block *sb, int type) |
437 | { |
438 | struct list_head *dirty; |
439 | struct dquot *dquot; |
440 | struct quota_info *dqopt = sb_dqopt(sb); |
441 | int cnt; |
442 | |
443 | down(&dqopt->dqonoff_sem); |
444 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
445 | if (type != -1 && cnt != type) |
446 | continue; |
447 | if (!sb_has_quota_enabled(sb, cnt)) |
448 | continue; |
449 | spin_lock(&dq_list_lock); |
450 | dirty = &dqopt->info[cnt].dqi_dirty_list; |
451 | while (!list_empty(dirty)) { |
452 | dquot = list_entry(dirty->next, struct dquot, dq_dirty); |
453 | /* Dirty and inactive can be only bad dquot... */ |
454 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { |
455 | clear_dquot_dirty(dquot); |
456 | continue; |
457 | } |
458 | /* Now we have active dquot from which someone is |
459 | * holding reference so we can safely just increase |
460 | * use count */ |
461 | atomic_inc(&dquot->dq_count); |
462 | dqstats.lookups++; |
463 | spin_unlock(&dq_list_lock); |
464 | sb->dq_op->write_dquot(dquot); |
465 | dqput(dquot); |
466 | spin_lock(&dq_list_lock); |
467 | } |
468 | spin_unlock(&dq_list_lock); |
469 | } |
470 | |
471 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
472 | if ((cnt == type || type == -1) && sb_has_quota_enabled(sb, cnt) |
473 | && info_dirty(&dqopt->info[cnt])) |
474 | sb->dq_op->write_info(sb, cnt); |
475 | spin_lock(&dq_list_lock); |
476 | dqstats.syncs++; |
477 | spin_unlock(&dq_list_lock); |
478 | up(&dqopt->dqonoff_sem); |
479 | |
480 | return 0; |
481 | } |
482 | |
483 | /* Free unused dquots from cache */ |
484 | static void prune_dqcache(int count) |
485 | { |
486 | struct list_head *head; |
487 | struct dquot *dquot; |
488 | |
489 | head = free_dquots.prev; |
490 | while (head != &free_dquots && count) { |
491 | dquot = list_entry(head, struct dquot, dq_free); |
492 | remove_dquot_hash(dquot); |
493 | remove_free_dquot(dquot); |
494 | remove_inuse(dquot); |
495 | kmem_cache_free(dquot_cachep, dquot); |
496 | count--; |
497 | head = free_dquots.prev; |
498 | } |
499 | } |
500 | |
501 | /* |
502 | * This is called from kswapd when we think we need some |
503 | * more memory |
504 | */ |
505 | |
506 | static int shrink_dqcache_memory(int nr, unsigned int gfp_mask) |
507 | { |
508 | if (nr) { |
509 | spin_lock(&dq_list_lock); |
510 | prune_dqcache(nr); |
511 | spin_unlock(&dq_list_lock); |
512 | } |
513 | return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure; |
514 | } |
515 | |
516 | /* |
517 | * Put reference to dquot |
518 | * NOTE: If you change this function please check whether dqput_blocks() works right... |
519 | * MUST be called with either dqptr_sem or dqonoff_sem held |
520 | */ |
521 | static void dqput(struct dquot *dquot) |
522 | { |
523 | if (!dquot) |
524 | return; |
525 | #ifdef __DQUOT_PARANOIA |
526 | if (!atomic_read(&dquot->dq_count)) { |
527 | printk("VFS: dqput: trying to free free dquot\n"); |
528 | printk("VFS: device %s, dquot of %s %d\n", |
529 | dquot->dq_sb->s_id, |
530 | quotatypes[dquot->dq_type], |
531 | dquot->dq_id); |
532 | BUG(); |
533 | } |
534 | #endif |
535 | |
536 | spin_lock(&dq_list_lock); |
537 | dqstats.drops++; |
538 | spin_unlock(&dq_list_lock); |
539 | we_slept: |
540 | spin_lock(&dq_list_lock); |
541 | if (atomic_read(&dquot->dq_count) > 1) { |
542 | /* We have more than one user... nothing to do */ |
543 | atomic_dec(&dquot->dq_count); |
544 | spin_unlock(&dq_list_lock); |
545 | return; |
546 | } |
547 | /* Need to release dquot? */ |
548 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { |
549 | spin_unlock(&dq_list_lock); |
550 | /* Commit dquot before releasing */ |
551 | dquot->dq_sb->dq_op->write_dquot(dquot); |
552 | goto we_slept; |
553 | } |
554 | /* Clear flag in case dquot was inactive (something bad happened) */ |
555 | clear_dquot_dirty(dquot); |
556 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { |
557 | spin_unlock(&dq_list_lock); |
558 | dquot->dq_sb->dq_op->release_dquot(dquot); |
559 | goto we_slept; |
560 | } |
561 | atomic_dec(&dquot->dq_count); |
562 | #ifdef __DQUOT_PARANOIA |
563 | /* sanity check */ |
564 | if (!list_empty(&dquot->dq_free)) |
565 | BUG(); |
566 | #endif |
567 | put_dquot_last(dquot); |
568 | spin_unlock(&dq_list_lock); |
569 | } |
570 | |
571 | static struct dquot *get_empty_dquot(struct super_block *sb, int type) |
572 | { |
573 | struct dquot *dquot; |
574 | |
575 | dquot = kmem_cache_alloc(dquot_cachep, SLAB_NOFS); |
576 | if(!dquot) |
577 | return NODQUOT; |
578 | |
579 | memset((caddr_t)dquot, 0, sizeof(struct dquot)); |
580 | sema_init(&dquot->dq_lock, 1); |
581 | INIT_LIST_HEAD(&dquot->dq_free); |
582 | INIT_LIST_HEAD(&dquot->dq_inuse); |
583 | INIT_HLIST_NODE(&dquot->dq_hash); |
584 | INIT_LIST_HEAD(&dquot->dq_dirty); |
585 | dquot->dq_sb = sb; |
586 | dquot->dq_type = type; |
587 | atomic_set(&dquot->dq_count, 1); |
588 | |
589 | return dquot; |
590 | } |
591 | |
592 | /* |
593 | * Get reference to dquot |
594 | * MUST be called with either dqptr_sem or dqonoff_sem held |
595 | */ |
596 | static struct dquot *dqget(struct super_block *sb, unsigned int id, int type) |
597 | { |
598 | unsigned int hashent = hashfn(sb, id, type); |
599 | struct dquot *dquot, *empty = NODQUOT; |
600 | |
601 | if (!sb_has_quota_enabled(sb, type)) |
602 | return NODQUOT; |
603 | we_slept: |
604 | spin_lock(&dq_list_lock); |
605 | if ((dquot = find_dquot(hashent, sb, id, type)) == NODQUOT) { |
606 | if (empty == NODQUOT) { |
607 | spin_unlock(&dq_list_lock); |
608 | if ((empty = get_empty_dquot(sb, type)) == NODQUOT) |
609 | schedule(); /* Try to wait for a moment... */ |
610 | goto we_slept; |
611 | } |
612 | dquot = empty; |
613 | dquot->dq_id = id; |
614 | /* all dquots go on the inuse_list */ |
615 | put_inuse(dquot); |
616 | /* hash it first so it can be found */ |
617 | insert_dquot_hash(dquot); |
618 | dqstats.lookups++; |
619 | spin_unlock(&dq_list_lock); |
620 | } else { |
621 | if (!atomic_read(&dquot->dq_count)) |
622 | remove_free_dquot(dquot); |
623 | atomic_inc(&dquot->dq_count); |
624 | dqstats.cache_hits++; |
625 | dqstats.lookups++; |
626 | spin_unlock(&dq_list_lock); |
627 | if (empty) |
628 | kmem_cache_free(dquot_cachep, empty); |
629 | } |
630 | /* Wait for dq_lock - after this we know that either dquot_release() is already |
631 | * finished or it will be canceled due to dq_count > 1 test */ |
632 | wait_on_dquot(dquot); |
633 | /* Read the dquot and instantiate it (everything done only if needed) */ |
634 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && sb->dq_op->acquire_dquot(dquot) < 0) { |
635 | dqput(dquot); |
636 | return NODQUOT; |
637 | } |
638 | #ifdef __DQUOT_PARANOIA |
639 | if (!dquot->dq_sb) /* Has somebody invalidated entry under us? */ |
640 | BUG(); |
641 | #endif |
642 | |
643 | return dquot; |
644 | } |
645 | |
646 | static int dqinit_needed(struct inode *inode, int type) |
647 | { |
648 | int cnt; |
649 | |
650 | if (IS_NOQUOTA(inode)) |
651 | return 0; |
652 | if (type != -1) |
653 | return inode->i_dquot[type] == NODQUOT; |
654 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
655 | if (inode->i_dquot[cnt] == NODQUOT) |
656 | return 1; |
657 | return 0; |
658 | } |
659 | |
660 | /* This routine is guarded by dqonoff_sem semaphore */ |
661 | static void add_dquot_ref(struct super_block *sb, int type) |
662 | { |
663 | struct list_head *p; |
664 | |
665 | restart: |
666 | file_list_lock(); |
667 | list_for_each(p, &sb->s_files) { |
668 | struct file *filp = list_entry(p, struct file, f_list); |
669 | struct inode *inode = filp->f_dentry->d_inode; |
670 | if (filp->f_mode & FMODE_WRITE && dqinit_needed(inode, type)) { |
671 | struct dentry *dentry = dget(filp->f_dentry); |
672 | file_list_unlock(); |
673 | sb->dq_op->initialize(inode, type); |
674 | dput(dentry); |
675 | /* As we may have blocked we had better restart... */ |
676 | goto restart; |
677 | } |
678 | } |
679 | file_list_unlock(); |
680 | } |
681 | |
682 | /* Return 0 if dqput() won't block (note that 1 doesn't necessarily mean blocking) */ |
683 | static inline int dqput_blocks(struct dquot *dquot) |
684 | { |
685 | if (atomic_read(&dquot->dq_count) <= 1) |
686 | return 1; |
687 | return 0; |
688 | } |
689 | |
690 | /* Remove references to dquots from inode - add dquot to list for freeing if needed */ |
691 | /* We can't race with anybody because we hold dqptr_sem for writing... */ |
692 | int remove_inode_dquot_ref(struct inode *inode, int type, struct list_head *tofree_head) |
693 | { |
694 | struct dquot *dquot = inode->i_dquot[type]; |
695 | |
696 | inode->i_dquot[type] = NODQUOT; |
697 | if (dquot != NODQUOT) { |
698 | if (dqput_blocks(dquot)) { |
699 | #ifdef __DQUOT_PARANOIA |
700 | if (atomic_read(&dquot->dq_count) != 1) |
701 | printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count)); |
702 | #endif |
703 | spin_lock(&dq_list_lock); |
704 | list_add(&dquot->dq_free, tofree_head); /* As dquot must have currently users it can't be on the free list... */ |
705 | spin_unlock(&dq_list_lock); |
706 | return 1; |
707 | } |
708 | else |
709 | dqput(dquot); /* We have guaranteed we won't block */ |
710 | } |
711 | return 0; |
712 | } |
713 | |
714 | /* Free list of dquots - called from inode.c */ |
715 | /* dquots are removed from inodes, no new references can be got so we are the only ones holding reference */ |
716 | static void put_dquot_list(struct list_head *tofree_head) |
717 | { |
718 | struct list_head *act_head; |
719 | struct dquot *dquot; |
720 | |
721 | act_head = tofree_head->next; |
722 | /* So now we have dquots on the list... Just free them */ |
723 | while (act_head != tofree_head) { |
724 | dquot = list_entry(act_head, struct dquot, dq_free); |
725 | act_head = act_head->next; |
726 | list_del_init(&dquot->dq_free); /* Remove dquot from the list so we won't have problems... */ |
727 | dqput(dquot); |
728 | } |
729 | } |
730 | |
731 | /* Gather all references from inodes and drop them */ |
732 | static void drop_dquot_ref(struct super_block *sb, int type) |
733 | { |
734 | LIST_HEAD(tofree_head); |
735 | |
736 | /* We need to be guarded against prune_icache to reach all the |
737 | * inodes - otherwise some can be on the local list of prune_icache */ |
738 | down(&iprune_sem); |
739 | down_write(&sb_dqopt(sb)->dqptr_sem); |
740 | remove_dquot_ref(sb, type, &tofree_head); |
741 | up_write(&sb_dqopt(sb)->dqptr_sem); |
742 | up(&iprune_sem); |
743 | put_dquot_list(&tofree_head); |
744 | } |
745 | |
746 | static inline void dquot_incr_inodes(struct dquot *dquot, unsigned long number) |
747 | { |
748 | dquot->dq_dqb.dqb_curinodes += number; |
749 | } |
750 | |
751 | static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) |
752 | { |
753 | dquot->dq_dqb.dqb_curspace += number; |
754 | } |
755 | |
756 | static inline void dquot_decr_inodes(struct dquot *dquot, unsigned long number) |
757 | { |
758 | if (dquot->dq_dqb.dqb_curinodes > number) |
759 | dquot->dq_dqb.dqb_curinodes -= number; |
760 | else |
761 | dquot->dq_dqb.dqb_curinodes = 0; |
762 | if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) |
763 | dquot->dq_dqb.dqb_itime = (time_t) 0; |
764 | clear_bit(DQ_INODES_B, &dquot->dq_flags); |
765 | } |
766 | |
767 | static inline void dquot_decr_space(struct dquot *dquot, qsize_t number) |
768 | { |
769 | if (dquot->dq_dqb.dqb_curspace > number) |
770 | dquot->dq_dqb.dqb_curspace -= number; |
771 | else |
772 | dquot->dq_dqb.dqb_curspace = 0; |
773 | if (toqb(dquot->dq_dqb.dqb_curspace) <= dquot->dq_dqb.dqb_bsoftlimit) |
774 | dquot->dq_dqb.dqb_btime = (time_t) 0; |
775 | clear_bit(DQ_BLKS_B, &dquot->dq_flags); |
776 | } |
777 | |
778 | static int flag_print_warnings = 1; |
779 | |
780 | static inline int need_print_warning(struct dquot *dquot) |
781 | { |
782 | if (!flag_print_warnings) |
783 | return 0; |
784 | |
785 | switch (dquot->dq_type) { |
786 | case USRQUOTA: |
787 | return current->fsuid == dquot->dq_id; |
788 | case GRPQUOTA: |
789 | return in_group_p(dquot->dq_id); |
790 | } |
791 | return 0; |
792 | } |
793 | |
794 | /* Values of warnings */ |
795 | #define NOWARN 0 |
796 | #define IHARDWARN 1 |
797 | #define ISOFTLONGWARN 2 |
798 | #define ISOFTWARN 3 |
799 | #define BHARDWARN 4 |
800 | #define BSOFTLONGWARN 5 |
801 | #define BSOFTWARN 6 |
802 | |
803 | /* Print warning to user which exceeded quota */ |
804 | static void print_warning(struct dquot *dquot, const char warntype) |
805 | { |
806 | char *msg = NULL; |
807 | int flag = (warntype == BHARDWARN || warntype == BSOFTLONGWARN) ? DQ_BLKS_B : |
808 | ((warntype == IHARDWARN || warntype == ISOFTLONGWARN) ? DQ_INODES_B : 0); |
809 | |
810 | if (!need_print_warning(dquot) || (flag && test_and_set_bit(flag, &dquot->dq_flags))) |
811 | return; |
812 | |
813 | tty_write_message(current->signal->tty, dquot->dq_sb->s_id); |
814 | if (warntype == ISOFTWARN || warntype == BSOFTWARN) |
815 | tty_write_message(current->signal->tty, ": warning, "); |
816 | else |
817 | tty_write_message(current->signal->tty, ": write failed, "); |
818 | tty_write_message(current->signal->tty, quotatypes[dquot->dq_type]); |
819 | switch (warntype) { |
820 | case IHARDWARN: |
821 | msg = " file limit reached.\r\n"; |
822 | break; |
823 | case ISOFTLONGWARN: |
824 | msg = " file quota exceeded too long.\r\n"; |
825 | break; |
826 | case ISOFTWARN: |
827 | msg = " file quota exceeded.\r\n"; |
828 | break; |
829 | case BHARDWARN: |
830 | msg = " block limit reached.\r\n"; |
831 | break; |
832 | case BSOFTLONGWARN: |
833 | msg = " block quota exceeded too long.\r\n"; |
834 | break; |
835 | case BSOFTWARN: |
836 | msg = " block quota exceeded.\r\n"; |
837 | break; |
838 | } |
839 | tty_write_message(current->signal->tty, msg); |
840 | } |
841 | |
842 | static inline void flush_warnings(struct dquot **dquots, char *warntype) |
843 | { |
844 | int i; |
845 | |
846 | for (i = 0; i < MAXQUOTAS; i++) |
847 | if (dquots[i] != NODQUOT && warntype[i] != NOWARN) |
848 | print_warning(dquots[i], warntype[i]); |
849 | } |
850 | |
851 | static inline char ignore_hardlimit(struct dquot *dquot) |
852 | { |
853 | struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; |
854 | |
855 | return capable(CAP_SYS_RESOURCE) && |
856 | (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || !(info->dqi_flags & V1_DQF_RSQUASH)); |
857 | } |
858 | |
859 | /* needs dq_data_lock */ |
860 | static int check_idq(struct dquot *dquot, ulong inodes, char *warntype) |
861 | { |
862 | *warntype = NOWARN; |
863 | if (inodes <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags)) |
864 | return QUOTA_OK; |
865 | |
866 | if (dquot->dq_dqb.dqb_ihardlimit && |
867 | (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_ihardlimit && |
868 | !ignore_hardlimit(dquot)) { |
869 | *warntype = IHARDWARN; |
870 | return NO_QUOTA; |
871 | } |
872 | |
873 | if (dquot->dq_dqb.dqb_isoftlimit && |
874 | (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit && |
875 | dquot->dq_dqb.dqb_itime && get_seconds() >= dquot->dq_dqb.dqb_itime && |
876 | !ignore_hardlimit(dquot)) { |
877 | *warntype = ISOFTLONGWARN; |
878 | return NO_QUOTA; |
879 | } |
880 | |
881 | if (dquot->dq_dqb.dqb_isoftlimit && |
882 | (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit && |
883 | dquot->dq_dqb.dqb_itime == 0) { |
884 | *warntype = ISOFTWARN; |
885 | dquot->dq_dqb.dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; |
886 | } |
887 | |
888 | return QUOTA_OK; |
889 | } |
890 | |
891 | /* needs dq_data_lock */ |
892 | static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) |
893 | { |
894 | *warntype = 0; |
895 | if (space <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags)) |
896 | return QUOTA_OK; |
897 | |
898 | if (dquot->dq_dqb.dqb_bhardlimit && |
899 | toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bhardlimit && |
900 | !ignore_hardlimit(dquot)) { |
901 | if (!prealloc) |
902 | *warntype = BHARDWARN; |
903 | return NO_QUOTA; |
904 | } |
905 | |
906 | if (dquot->dq_dqb.dqb_bsoftlimit && |
907 | toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit && |
908 | dquot->dq_dqb.dqb_btime && get_seconds() >= dquot->dq_dqb.dqb_btime && |
909 | !ignore_hardlimit(dquot)) { |
910 | if (!prealloc) |
911 | *warntype = BSOFTLONGWARN; |
912 | return NO_QUOTA; |
913 | } |
914 | |
915 | if (dquot->dq_dqb.dqb_bsoftlimit && |
916 | toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit && |
917 | dquot->dq_dqb.dqb_btime == 0) { |
918 | if (!prealloc) { |
919 | *warntype = BSOFTWARN; |
920 | dquot->dq_dqb.dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace; |
921 | } |
922 | else |
923 | /* |
924 | * We don't allow preallocation to exceed softlimit so exceeding will |
925 | * be always printed |
926 | */ |
927 | return NO_QUOTA; |
928 | } |
929 | |
930 | return QUOTA_OK; |
931 | } |
932 | |
933 | /* |
934 | * Initialize quota pointers in inode |
935 | * Transaction must be started at entry |
936 | */ |
937 | int dquot_initialize(struct inode *inode, int type) |
938 | { |
939 | unsigned int id = 0; |
940 | int cnt, ret = 0; |
941 | |
942 | /* First test before acquiring semaphore - solves deadlocks when we |
943 | * re-enter the quota code and are already holding the semaphore */ |
944 | if (IS_NOQUOTA(inode)) |
945 | return 0; |
946 | down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
947 | /* Having dqptr_sem we know NOQUOTA flags can't be altered... */ |
948 | if (IS_NOQUOTA(inode)) |
949 | goto out_err; |
950 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
951 | if (type != -1 && cnt != type) |
952 | continue; |
953 | if (inode->i_dquot[cnt] == NODQUOT) { |
954 | switch (cnt) { |
955 | case USRQUOTA: |
956 | id = inode->i_uid; |
957 | break; |
958 | case GRPQUOTA: |
959 | id = inode->i_gid; |
960 | break; |
961 | } |
962 | inode->i_dquot[cnt] = dqget(inode->i_sb, id, cnt); |
963 | } |
964 | } |
965 | out_err: |
966 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
967 | return ret; |
968 | } |
969 | |
970 | /* |
971 | * Release all quotas referenced by inode |
972 | * Transaction must be started at an entry |
973 | */ |
974 | int dquot_drop(struct inode *inode) |
975 | { |
976 | int cnt; |
977 | |
978 | down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
979 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
980 | if (inode->i_dquot[cnt] != NODQUOT) { |
981 | dqput(inode->i_dquot[cnt]); |
982 | inode->i_dquot[cnt] = NODQUOT; |
983 | } |
984 | } |
985 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
986 | return 0; |
987 | } |
988 | |
989 | /* |
990 | * Following four functions update i_blocks+i_bytes fields and |
991 | * quota information (together with appropriate checks) |
992 | * NOTE: We absolutely rely on the fact that caller dirties |
993 | * the inode (usually macros in quotaops.h care about this) and |
994 | * holds a handle for the current transaction so that dquot write and |
995 | * inode write go into the same transaction. |
996 | */ |
997 | |
998 | /* |
999 | * This operation can block, but only after everything is updated |
1000 | */ |
1001 | int dquot_alloc_space(struct inode *inode, qsize_t number, int warn) |
1002 | { |
1003 | int cnt, ret = NO_QUOTA; |
1004 | char warntype[MAXQUOTAS]; |
1005 | |
1006 | /* First test before acquiring semaphore - solves deadlocks when we |
1007 | * re-enter the quota code and are already holding the semaphore */ |
1008 | if (IS_NOQUOTA(inode)) { |
1009 | out_add: |
1010 | inode_add_bytes(inode, number); |
1011 | return QUOTA_OK; |
1012 | } |
1013 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1014 | warntype[cnt] = NOWARN; |
1015 | |
1016 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1017 | if (IS_NOQUOTA(inode)) { /* Now we can do reliable test... */ |
1018 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1019 | goto out_add; |
1020 | } |
1021 | spin_lock(&dq_data_lock); |
1022 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1023 | if (inode->i_dquot[cnt] == NODQUOT) |
1024 | continue; |
1025 | if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt) == NO_QUOTA) |
1026 | goto warn_put_all; |
1027 | } |
1028 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1029 | if (inode->i_dquot[cnt] == NODQUOT) |
1030 | continue; |
1031 | dquot_incr_space(inode->i_dquot[cnt], number); |
1032 | } |
1033 | inode_add_bytes(inode, number); |
1034 | ret = QUOTA_OK; |
1035 | warn_put_all: |
1036 | spin_unlock(&dq_data_lock); |
1037 | if (ret == QUOTA_OK) |
1038 | /* Dirtify all the dquots - this can block when journalling */ |
1039 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1040 | if (inode->i_dquot[cnt]) |
1041 | mark_dquot_dirty(inode->i_dquot[cnt]); |
1042 | flush_warnings(inode->i_dquot, warntype); |
1043 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1044 | return ret; |
1045 | } |
1046 | |
1047 | /* |
1048 | * This operation can block, but only after everything is updated |
1049 | */ |
1050 | int dquot_alloc_inode(const struct inode *inode, unsigned long number) |
1051 | { |
1052 | int cnt, ret = NO_QUOTA; |
1053 | char warntype[MAXQUOTAS]; |
1054 | |
1055 | /* First test before acquiring semaphore - solves deadlocks when we |
1056 | * re-enter the quota code and are already holding the semaphore */ |
1057 | if (IS_NOQUOTA(inode)) |
1058 | return QUOTA_OK; |
1059 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1060 | warntype[cnt] = NOWARN; |
1061 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1062 | if (IS_NOQUOTA(inode)) { |
1063 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1064 | return QUOTA_OK; |
1065 | } |
1066 | spin_lock(&dq_data_lock); |
1067 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1068 | if (inode->i_dquot[cnt] == NODQUOT) |
1069 | continue; |
1070 | if (check_idq(inode->i_dquot[cnt], number, warntype+cnt) == NO_QUOTA) |
1071 | goto warn_put_all; |
1072 | } |
1073 | |
1074 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1075 | if (inode->i_dquot[cnt] == NODQUOT) |
1076 | continue; |
1077 | dquot_incr_inodes(inode->i_dquot[cnt], number); |
1078 | } |
1079 | ret = QUOTA_OK; |
1080 | warn_put_all: |
1081 | spin_unlock(&dq_data_lock); |
1082 | if (ret == QUOTA_OK) |
1083 | /* Dirtify all the dquots - this can block when journalling */ |
1084 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1085 | if (inode->i_dquot[cnt]) |
1086 | mark_dquot_dirty(inode->i_dquot[cnt]); |
1087 | flush_warnings((struct dquot **)inode->i_dquot, warntype); |
1088 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1089 | return ret; |
1090 | } |
1091 | |
1092 | /* |
1093 | * This operation can block, but only after everything is updated |
1094 | */ |
1095 | int dquot_free_space(struct inode *inode, qsize_t number) |
1096 | { |
1097 | unsigned int cnt; |
1098 | |
1099 | /* First test before acquiring semaphore - solves deadlocks when we |
1100 | * re-enter the quota code and are already holding the semaphore */ |
1101 | if (IS_NOQUOTA(inode)) { |
1102 | out_sub: |
1103 | inode_sub_bytes(inode, number); |
1104 | return QUOTA_OK; |
1105 | } |
1106 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1107 | /* Now recheck reliably when holding dqptr_sem */ |
1108 | if (IS_NOQUOTA(inode)) { |
1109 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1110 | goto out_sub; |
1111 | } |
1112 | spin_lock(&dq_data_lock); |
1113 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1114 | if (inode->i_dquot[cnt] == NODQUOT) |
1115 | continue; |
1116 | dquot_decr_space(inode->i_dquot[cnt], number); |
1117 | } |
1118 | inode_sub_bytes(inode, number); |
1119 | spin_unlock(&dq_data_lock); |
1120 | /* Dirtify all the dquots - this can block when journalling */ |
1121 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1122 | if (inode->i_dquot[cnt]) |
1123 | mark_dquot_dirty(inode->i_dquot[cnt]); |
1124 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1125 | return QUOTA_OK; |
1126 | } |
1127 | |
1128 | /* |
1129 | * This operation can block, but only after everything is updated |
1130 | */ |
1131 | int dquot_free_inode(const struct inode *inode, unsigned long number) |
1132 | { |
1133 | unsigned int cnt; |
1134 | |
1135 | /* First test before acquiring semaphore - solves deadlocks when we |
1136 | * re-enter the quota code and are already holding the semaphore */ |
1137 | if (IS_NOQUOTA(inode)) |
1138 | return QUOTA_OK; |
1139 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1140 | /* Now recheck reliably when holding dqptr_sem */ |
1141 | if (IS_NOQUOTA(inode)) { |
1142 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1143 | return QUOTA_OK; |
1144 | } |
1145 | spin_lock(&dq_data_lock); |
1146 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1147 | if (inode->i_dquot[cnt] == NODQUOT) |
1148 | continue; |
1149 | dquot_decr_inodes(inode->i_dquot[cnt], number); |
1150 | } |
1151 | spin_unlock(&dq_data_lock); |
1152 | /* Dirtify all the dquots - this can block when journalling */ |
1153 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1154 | if (inode->i_dquot[cnt]) |
1155 | mark_dquot_dirty(inode->i_dquot[cnt]); |
1156 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1157 | return QUOTA_OK; |
1158 | } |
1159 | |
1160 | /* |
1161 | * Transfer the number of inode and blocks from one diskquota to an other. |
1162 | * |
1163 | * This operation can block, but only after everything is updated |
1164 | * A transaction must be started when entering this function. |
1165 | */ |
1166 | int dquot_transfer(struct inode *inode, struct iattr *iattr) |
1167 | { |
1168 | qsize_t space; |
1169 | struct dquot *transfer_from[MAXQUOTAS]; |
1170 | struct dquot *transfer_to[MAXQUOTAS]; |
1171 | int cnt, ret = NO_QUOTA, chuid = (iattr->ia_valid & ATTR_UID) && inode->i_uid != iattr->ia_uid, |
1172 | chgid = (iattr->ia_valid & ATTR_GID) && inode->i_gid != iattr->ia_gid; |
1173 | char warntype[MAXQUOTAS]; |
1174 | |
1175 | /* First test before acquiring semaphore - solves deadlocks when we |
1176 | * re-enter the quota code and are already holding the semaphore */ |
1177 | if (IS_NOQUOTA(inode)) |
1178 | return QUOTA_OK; |
1179 | /* Clear the arrays */ |
1180 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1181 | transfer_to[cnt] = transfer_from[cnt] = NODQUOT; |
1182 | warntype[cnt] = NOWARN; |
1183 | } |
1184 | down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1185 | /* Now recheck reliably when holding dqptr_sem */ |
1186 | if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ |
1187 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1188 | return QUOTA_OK; |
1189 | } |
1190 | /* First build the transfer_to list - here we can block on |
1191 | * reading/instantiating of dquots. We know that the transaction for |
1192 | * us was already started so we don't violate lock ranking here */ |
1193 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1194 | switch (cnt) { |
1195 | case USRQUOTA: |
1196 | if (!chuid) |
1197 | continue; |
1198 | transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_uid, cnt); |
1199 | break; |
1200 | case GRPQUOTA: |
1201 | if (!chgid) |
1202 | continue; |
1203 | transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_gid, cnt); |
1204 | break; |
1205 | } |
1206 | } |
1207 | spin_lock(&dq_data_lock); |
1208 | space = inode_get_bytes(inode); |
1209 | /* Build the transfer_from list and check the limits */ |
1210 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1211 | if (transfer_to[cnt] == NODQUOT) |
1212 | continue; |
1213 | transfer_from[cnt] = inode->i_dquot[cnt]; |
1214 | if (check_idq(transfer_to[cnt], 1, warntype+cnt) == NO_QUOTA || |
1215 | check_bdq(transfer_to[cnt], space, 0, warntype+cnt) == NO_QUOTA) |
1216 | goto warn_put_all; |
1217 | } |
1218 | |
1219 | /* |
1220 | * Finally perform the needed transfer from transfer_from to transfer_to |
1221 | */ |
1222 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1223 | /* |
1224 | * Skip changes for same uid or gid or for turned off quota-type. |
1225 | */ |
1226 | if (transfer_to[cnt] == NODQUOT) |
1227 | continue; |
1228 | |
1229 | /* Due to IO error we might not have transfer_from[] structure */ |
1230 | if (transfer_from[cnt]) { |
1231 | dquot_decr_inodes(transfer_from[cnt], 1); |
1232 | dquot_decr_space(transfer_from[cnt], space); |
1233 | } |
1234 | |
1235 | dquot_incr_inodes(transfer_to[cnt], 1); |
1236 | dquot_incr_space(transfer_to[cnt], space); |
1237 | |
1238 | inode->i_dquot[cnt] = transfer_to[cnt]; |
1239 | } |
1240 | ret = QUOTA_OK; |
1241 | warn_put_all: |
1242 | spin_unlock(&dq_data_lock); |
1243 | /* Dirtify all the dquots - this can block when journalling */ |
1244 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1245 | if (transfer_from[cnt]) |
1246 | mark_dquot_dirty(transfer_from[cnt]); |
1247 | if (transfer_to[cnt]) |
1248 | mark_dquot_dirty(transfer_to[cnt]); |
1249 | } |
1250 | flush_warnings(transfer_to, warntype); |
1251 | |
1252 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1253 | if (ret == QUOTA_OK && transfer_from[cnt] != NODQUOT) |
1254 | dqput(transfer_from[cnt]); |
1255 | if (ret == NO_QUOTA && transfer_to[cnt] != NODQUOT) |
1256 | dqput(transfer_to[cnt]); |
1257 | } |
1258 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1259 | return ret; |
1260 | } |
1261 | |
1262 | /* |
1263 | * Write info of quota file to disk |
1264 | */ |
1265 | int dquot_commit_info(struct super_block *sb, int type) |
1266 | { |
1267 | int ret; |
1268 | struct quota_info *dqopt = sb_dqopt(sb); |
1269 | |
1270 | down(&dqopt->dqio_sem); |
1271 | ret = dqopt->ops[type]->write_file_info(sb, type); |
1272 | up(&dqopt->dqio_sem); |
1273 | return ret; |
1274 | } |
1275 | |
1276 | /* |
1277 | * Definitions of diskquota operations. |
1278 | */ |
1279 | struct dquot_operations dquot_operations = { |
1280 | .initialize = dquot_initialize, |
1281 | .drop = dquot_drop, |
1282 | .alloc_space = dquot_alloc_space, |
1283 | .alloc_inode = dquot_alloc_inode, |
1284 | .free_space = dquot_free_space, |
1285 | .free_inode = dquot_free_inode, |
1286 | .transfer = dquot_transfer, |
1287 | .write_dquot = dquot_commit, |
1288 | .acquire_dquot = dquot_acquire, |
1289 | .release_dquot = dquot_release, |
1290 | .mark_dirty = dquot_mark_dquot_dirty, |
1291 | .write_info = dquot_commit_info |
1292 | }; |
1293 | |
1294 | static inline void set_enable_flags(struct quota_info *dqopt, int type) |
1295 | { |
1296 | switch (type) { |
1297 | case USRQUOTA: |
1298 | dqopt->flags |= DQUOT_USR_ENABLED; |
1299 | break; |
1300 | case GRPQUOTA: |
1301 | dqopt->flags |= DQUOT_GRP_ENABLED; |
1302 | break; |
1303 | } |
1304 | } |
1305 | |
1306 | static inline void reset_enable_flags(struct quota_info *dqopt, int type) |
1307 | { |
1308 | switch (type) { |
1309 | case USRQUOTA: |
1310 | dqopt->flags &= ~DQUOT_USR_ENABLED; |
1311 | break; |
1312 | case GRPQUOTA: |
1313 | dqopt->flags &= ~DQUOT_GRP_ENABLED; |
1314 | break; |
1315 | } |
1316 | } |
1317 | |
1318 | /* |
1319 | * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) |
1320 | */ |
1321 | int vfs_quota_off(struct super_block *sb, int type) |
1322 | { |
1323 | int cnt; |
1324 | struct quota_info *dqopt = sb_dqopt(sb); |
1325 | struct inode *toputinode[MAXQUOTAS]; |
1326 | struct vfsmount *toputmnt[MAXQUOTAS]; |
1327 | |
1328 | /* We need to serialize quota_off() for device */ |
1329 | down(&dqopt->dqonoff_sem); |
1330 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1331 | toputinode[cnt] = NULL; |
1332 | toputmnt[cnt] = NULL; |
1333 | if (type != -1 && cnt != type) |
1334 | continue; |
1335 | if (!sb_has_quota_enabled(sb, cnt)) |
1336 | continue; |
1337 | reset_enable_flags(dqopt, cnt); |
1338 | |
1339 | /* Note: these are blocking operations */ |
1340 | drop_dquot_ref(sb, cnt); |
1341 | invalidate_dquots(sb, cnt); |
1342 | /* |
1343 | * Now all dquots should be invalidated, all writes done so we should be only |
1344 | * users of the info. No locks needed. |
1345 | */ |
1346 | if (info_dirty(&dqopt->info[cnt])) |
1347 | sb->dq_op->write_info(sb, cnt); |
1348 | if (dqopt->ops[cnt]->free_file_info) |
1349 | dqopt->ops[cnt]->free_file_info(sb, cnt); |
1350 | put_quota_format(dqopt->info[cnt].dqi_format); |
1351 | |
1352 | toputinode[cnt] = dqopt->files[cnt]; |
1353 | toputmnt[cnt] = dqopt->mnt[cnt]; |
1354 | dqopt->files[cnt] = NULL; |
1355 | dqopt->mnt[cnt] = NULL; |
1356 | dqopt->info[cnt].dqi_flags = 0; |
1357 | dqopt->info[cnt].dqi_igrace = 0; |
1358 | dqopt->info[cnt].dqi_bgrace = 0; |
1359 | dqopt->ops[cnt] = NULL; |
1360 | } |
1361 | up(&dqopt->dqonoff_sem); |
1362 | /* Sync the superblock so that buffers with quota data are written to |
1363 | * disk (and so userspace sees correct data afterwards). |
1364 | * The reference to vfsmnt we are still holding protects us from |
1365 | * umount (we don't have it only when quotas are turned on/off for |
1366 | * journal replay but in that case we are guarded by the fs anyway). */ |
1367 | if (sb->s_op->sync_fs) |
1368 | sb->s_op->sync_fs(sb, 1); |
1369 | sync_blockdev(sb->s_bdev); |
1370 | /* Now the quota files are just ordinary files and we can set the |
1371 | * inode flags back. Moreover we discard the pagecache so that |
1372 | * userspace sees the writes we did bypassing the pagecache. We |
1373 | * must also discard the blockdev buffers so that we see the |
1374 | * changes done by userspace on the next quotaon() */ |
1375 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1376 | if (toputinode[cnt]) { |
1377 | down(&dqopt->dqonoff_sem); |
1378 | /* If quota was reenabled in the meantime, we have |
1379 | * nothing to do */ |
1380 | if (!sb_has_quota_enabled(sb, cnt)) { |
1381 | down(&toputinode[cnt]->i_sem); |
1382 | toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | |
1383 | S_NOATIME | S_NOQUOTA); |
1384 | truncate_inode_pages(&toputinode[cnt]->i_data, 0); |
1385 | up(&toputinode[cnt]->i_sem); |
1386 | mark_inode_dirty(toputinode[cnt]); |
1387 | iput(toputinode[cnt]); |
1388 | } |
1389 | up(&dqopt->dqonoff_sem); |
1390 | /* We don't hold the reference when we turned on quotas |
1391 | * just for the journal replay... */ |
1392 | if (toputmnt[cnt]) |
1393 | mntput(toputmnt[cnt]); |
1394 | } |
1395 | if (sb->s_bdev) |
1396 | invalidate_bdev(sb->s_bdev, 0); |
1397 | return 0; |
1398 | } |
1399 | |
1400 | /* |
1401 | * Turn quotas on on a device |
1402 | */ |
1403 | |
1404 | /* Helper function when we already have the inode */ |
1405 | static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) |
1406 | { |
1407 | struct quota_format_type *fmt = find_quota_format(format_id); |
1408 | struct super_block *sb = inode->i_sb; |
1409 | struct quota_info *dqopt = sb_dqopt(sb); |
1410 | int error; |
1411 | int oldflags = -1; |
1412 | |
1413 | if (!fmt) |
1414 | return -ESRCH; |
1415 | if (!S_ISREG(inode->i_mode)) { |
1416 | error = -EACCES; |
1417 | goto out_fmt; |
1418 | } |
1419 | if (IS_RDONLY(inode)) { |
1420 | error = -EROFS; |
1421 | goto out_fmt; |
1422 | } |
1423 | if (!sb->s_op->quota_write || !sb->s_op->quota_read) { |
1424 | error = -EINVAL; |
1425 | goto out_fmt; |
1426 | } |
1427 | |
1428 | /* As we bypass the pagecache we must now flush the inode so that |
1429 | * we see all the changes from userspace... */ |
1430 | write_inode_now(inode, 1); |
1431 | /* And now flush the block cache so that kernel sees the changes */ |
1432 | invalidate_bdev(sb->s_bdev, 0); |
1433 | down(&inode->i_sem); |
1434 | down(&dqopt->dqonoff_sem); |
1435 | if (sb_has_quota_enabled(sb, type)) { |
1436 | error = -EBUSY; |
1437 | goto out_lock; |
1438 | } |
1439 | /* We don't want quota and atime on quota files (deadlocks possible) |
1440 | * Also nobody should write to the file - we use special IO operations |
1441 | * which ignore the immutable bit. */ |
1442 | down_write(&dqopt->dqptr_sem); |
1443 | oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | S_NOQUOTA); |
1444 | inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; |
1445 | up_write(&dqopt->dqptr_sem); |
1446 | sb->dq_op->drop(inode); |
1447 | |
1448 | error = -EIO; |
1449 | dqopt->files[type] = igrab(inode); |
1450 | if (!dqopt->files[type]) |
1451 | goto out_lock; |
1452 | error = -EINVAL; |
1453 | if (!fmt->qf_ops->check_quota_file(sb, type)) |
1454 | goto out_file_init; |
1455 | |
1456 | dqopt->ops[type] = fmt->qf_ops; |
1457 | dqopt->info[type].dqi_format = fmt; |
1458 | INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); |
1459 | down(&dqopt->dqio_sem); |
1460 | if ((error = dqopt->ops[type]->read_file_info(sb, type)) < 0) { |
1461 | up(&dqopt->dqio_sem); |
1462 | goto out_file_init; |
1463 | } |
1464 | up(&dqopt->dqio_sem); |
1465 | up(&inode->i_sem); |
1466 | set_enable_flags(dqopt, type); |
1467 | |
1468 | add_dquot_ref(sb, type); |
1469 | up(&dqopt->dqonoff_sem); |
1470 | |
1471 | return 0; |
1472 | |
1473 | out_file_init: |
1474 | dqopt->files[type] = NULL; |
1475 | iput(inode); |
1476 | out_lock: |
1477 | up(&dqopt->dqonoff_sem); |
1478 | if (oldflags != -1) { |
1479 | down_write(&dqopt->dqptr_sem); |
1480 | /* Set the flags back (in the case of accidental quotaon() |
1481 | * on a wrong file we don't want to mess up the flags) */ |
1482 | inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); |
1483 | inode->i_flags |= oldflags; |
1484 | up_write(&dqopt->dqptr_sem); |
1485 | } |
1486 | up(&inode->i_sem); |
1487 | out_fmt: |
1488 | put_quota_format(fmt); |
1489 | |
1490 | return error; |
1491 | } |
1492 | |
1493 | /* Actual function called from quotactl() */ |
1494 | int vfs_quota_on(struct super_block *sb, int type, int format_id, char *path) |
1495 | { |
1496 | struct nameidata nd; |
1497 | int error; |
1498 | |
1499 | error = path_lookup(path, LOOKUP_FOLLOW, &nd); |
1500 | if (error < 0) |
1501 | return error; |
1502 | error = security_quota_on(nd.dentry); |
1503 | if (error) |
1504 | goto out_path; |
1505 | /* Quota file not on the same filesystem? */ |
1506 | if (nd.mnt->mnt_sb != sb) |
1507 | error = -EXDEV; |
1508 | else { |
1509 | error = vfs_quota_on_inode(nd.dentry->d_inode, type, format_id); |
1510 | if (!error) |
1511 | sb_dqopt(sb)->mnt[type] = mntget(nd.mnt); |
1512 | } |
1513 | out_path: |
1514 | path_release(&nd); |
1515 | return error; |
1516 | } |
1517 | |
1518 | /* |
1519 | * This function is used when filesystem needs to initialize quotas |
1520 | * during mount time. |
1521 | */ |
1522 | int vfs_quota_on_mount(int type, int format_id, struct dentry *dentry) |
1523 | { |
1524 | int error; |
1525 | |
1526 | error = security_quota_on(dentry); |
1527 | if (error) |
1528 | return error; |
1529 | return vfs_quota_on_inode(dentry->d_inode, type, format_id); |
1530 | } |
1531 | |
1532 | /* Generic routine for getting common part of quota structure */ |
1533 | static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di) |
1534 | { |
1535 | struct mem_dqblk *dm = &dquot->dq_dqb; |
1536 | |
1537 | spin_lock(&dq_data_lock); |
1538 | di->dqb_bhardlimit = dm->dqb_bhardlimit; |
1539 | di->dqb_bsoftlimit = dm->dqb_bsoftlimit; |
1540 | di->dqb_curspace = dm->dqb_curspace; |
1541 | di->dqb_ihardlimit = dm->dqb_ihardlimit; |
1542 | di->dqb_isoftlimit = dm->dqb_isoftlimit; |
1543 | di->dqb_curinodes = dm->dqb_curinodes; |
1544 | di->dqb_btime = dm->dqb_btime; |
1545 | di->dqb_itime = dm->dqb_itime; |
1546 | di->dqb_valid = QIF_ALL; |
1547 | spin_unlock(&dq_data_lock); |
1548 | } |
1549 | |
1550 | int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di) |
1551 | { |
1552 | struct dquot *dquot; |
1553 | |
1554 | down(&sb_dqopt(sb)->dqonoff_sem); |
1555 | if (!(dquot = dqget(sb, id, type))) { |
1556 | up(&sb_dqopt(sb)->dqonoff_sem); |
1557 | return -ESRCH; |
1558 | } |
1559 | do_get_dqblk(dquot, di); |
1560 | dqput(dquot); |
1561 | up(&sb_dqopt(sb)->dqonoff_sem); |
1562 | return 0; |
1563 | } |
1564 | |
1565 | /* Generic routine for setting common part of quota structure */ |
1566 | static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di) |
1567 | { |
1568 | struct mem_dqblk *dm = &dquot->dq_dqb; |
1569 | int check_blim = 0, check_ilim = 0; |
1570 | |
1571 | spin_lock(&dq_data_lock); |
1572 | if (di->dqb_valid & QIF_SPACE) { |
1573 | dm->dqb_curspace = di->dqb_curspace; |
1574 | check_blim = 1; |
1575 | } |
1576 | if (di->dqb_valid & QIF_BLIMITS) { |
1577 | dm->dqb_bsoftlimit = di->dqb_bsoftlimit; |
1578 | dm->dqb_bhardlimit = di->dqb_bhardlimit; |
1579 | check_blim = 1; |
1580 | } |
1581 | if (di->dqb_valid & QIF_INODES) { |
1582 | dm->dqb_curinodes = di->dqb_curinodes; |
1583 | check_ilim = 1; |
1584 | } |
1585 | if (di->dqb_valid & QIF_ILIMITS) { |
1586 | dm->dqb_isoftlimit = di->dqb_isoftlimit; |
1587 | dm->dqb_ihardlimit = di->dqb_ihardlimit; |
1588 | check_ilim = 1; |
1589 | } |
1590 | if (di->dqb_valid & QIF_BTIME) |
1591 | dm->dqb_btime = di->dqb_btime; |
1592 | if (di->dqb_valid & QIF_ITIME) |
1593 | dm->dqb_itime = di->dqb_itime; |
1594 | |
1595 | if (check_blim) { |
1596 | if (!dm->dqb_bsoftlimit || toqb(dm->dqb_curspace) < dm->dqb_bsoftlimit) { |
1597 | dm->dqb_btime = 0; |
1598 | clear_bit(DQ_BLKS_B, &dquot->dq_flags); |
1599 | } |
1600 | else if (!(di->dqb_valid & QIF_BTIME)) /* Set grace only if user hasn't provided his own... */ |
1601 | dm->dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace; |
1602 | } |
1603 | if (check_ilim) { |
1604 | if (!dm->dqb_isoftlimit || dm->dqb_curinodes < dm->dqb_isoftlimit) { |
1605 | dm->dqb_itime = 0; |
1606 | clear_bit(DQ_INODES_B, &dquot->dq_flags); |
1607 | } |
1608 | else if (!(di->dqb_valid & QIF_ITIME)) /* Set grace only if user hasn't provided his own... */ |
1609 | dm->dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; |
1610 | } |
1611 | if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || dm->dqb_isoftlimit) |
1612 | clear_bit(DQ_FAKE_B, &dquot->dq_flags); |
1613 | else |
1614 | set_bit(DQ_FAKE_B, &dquot->dq_flags); |
1615 | spin_unlock(&dq_data_lock); |
1616 | mark_dquot_dirty(dquot); |
1617 | } |
1618 | |
1619 | int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di) |
1620 | { |
1621 | struct dquot *dquot; |
1622 | |
1623 | down(&sb_dqopt(sb)->dqonoff_sem); |
1624 | if (!(dquot = dqget(sb, id, type))) { |
1625 | up(&sb_dqopt(sb)->dqonoff_sem); |
1626 | return -ESRCH; |
1627 | } |
1628 | do_set_dqblk(dquot, di); |
1629 | dqput(dquot); |
1630 | up(&sb_dqopt(sb)->dqonoff_sem); |
1631 | return 0; |
1632 | } |
1633 | |
1634 | /* Generic routine for getting common part of quota file information */ |
1635 | int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) |
1636 | { |
1637 | struct mem_dqinfo *mi; |
1638 | |
1639 | down(&sb_dqopt(sb)->dqonoff_sem); |
1640 | if (!sb_has_quota_enabled(sb, type)) { |
1641 | up(&sb_dqopt(sb)->dqonoff_sem); |
1642 | return -ESRCH; |
1643 | } |
1644 | mi = sb_dqopt(sb)->info + type; |
1645 | spin_lock(&dq_data_lock); |
1646 | ii->dqi_bgrace = mi->dqi_bgrace; |
1647 | ii->dqi_igrace = mi->dqi_igrace; |
1648 | ii->dqi_flags = mi->dqi_flags & DQF_MASK; |
1649 | ii->dqi_valid = IIF_ALL; |
1650 | spin_unlock(&dq_data_lock); |
1651 | up(&sb_dqopt(sb)->dqonoff_sem); |
1652 | return 0; |
1653 | } |
1654 | |
1655 | /* Generic routine for setting common part of quota file information */ |
1656 | int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) |
1657 | { |
1658 | struct mem_dqinfo *mi; |
1659 | |
1660 | down(&sb_dqopt(sb)->dqonoff_sem); |
1661 | if (!sb_has_quota_enabled(sb, type)) { |
1662 | up(&sb_dqopt(sb)->dqonoff_sem); |
1663 | return -ESRCH; |
1664 | } |
1665 | mi = sb_dqopt(sb)->info + type; |
1666 | spin_lock(&dq_data_lock); |
1667 | if (ii->dqi_valid & IIF_BGRACE) |
1668 | mi->dqi_bgrace = ii->dqi_bgrace; |
1669 | if (ii->dqi_valid & IIF_IGRACE) |
1670 | mi->dqi_igrace = ii->dqi_igrace; |
1671 | if (ii->dqi_valid & IIF_FLAGS) |
1672 | mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | (ii->dqi_flags & DQF_MASK); |
1673 | spin_unlock(&dq_data_lock); |
1674 | mark_info_dirty(sb, type); |
1675 | /* Force write to disk */ |
1676 | sb->dq_op->write_info(sb, type); |
1677 | up(&sb_dqopt(sb)->dqonoff_sem); |
1678 | return 0; |
1679 | } |
1680 | |
1681 | struct quotactl_ops vfs_quotactl_ops = { |
1682 | .quota_on = vfs_quota_on, |
1683 | .quota_off = vfs_quota_off, |
1684 | .quota_sync = vfs_quota_sync, |
1685 | .get_info = vfs_get_dqinfo, |
1686 | .set_info = vfs_set_dqinfo, |
1687 | .get_dqblk = vfs_get_dqblk, |
1688 | .set_dqblk = vfs_set_dqblk |
1689 | }; |
1690 | |
1691 | static ctl_table fs_dqstats_table[] = { |
1692 | { |
1693 | .ctl_name = FS_DQ_LOOKUPS, |
1694 | .procname = "lookups", |
1695 | .data = &dqstats.lookups, |
1696 | .maxlen = sizeof(int), |
1697 | .mode = 0444, |
1698 | .proc_handler = &proc_dointvec, |
1699 | }, |
1700 | { |
1701 | .ctl_name = FS_DQ_DROPS, |
1702 | .procname = "drops", |
1703 | .data = &dqstats.drops, |
1704 | .maxlen = sizeof(int), |
1705 | .mode = 0444, |
1706 | .proc_handler = &proc_dointvec, |
1707 | }, |
1708 | { |
1709 | .ctl_name = FS_DQ_READS, |
1710 | .procname = "reads", |
1711 | .data = &dqstats.reads, |
1712 | .maxlen = sizeof(int), |
1713 | .mode = 0444, |
1714 | .proc_handler = &proc_dointvec, |
1715 | }, |
1716 | { |
1717 | .ctl_name = FS_DQ_WRITES, |
1718 | .procname = "writes", |
1719 | .data = &dqstats.writes, |
1720 | .maxlen = sizeof(int), |
1721 | .mode = 0444, |
1722 | .proc_handler = &proc_dointvec, |
1723 | }, |
1724 | { |
1725 | .ctl_name = FS_DQ_CACHE_HITS, |
1726 | .procname = "cache_hits", |
1727 | .data = &dqstats.cache_hits, |
1728 | .maxlen = sizeof(int), |
1729 | .mode = 0444, |
1730 | .proc_handler = &proc_dointvec, |
1731 | }, |
1732 | { |
1733 | .ctl_name = FS_DQ_ALLOCATED, |
1734 | .procname = "allocated_dquots", |
1735 | .data = &dqstats.allocated_dquots, |
1736 | .maxlen = sizeof(int), |
1737 | .mode = 0444, |
1738 | .proc_handler = &proc_dointvec, |
1739 | }, |
1740 | { |
1741 | .ctl_name = FS_DQ_FREE, |
1742 | .procname = "free_dquots", |
1743 | .data = &dqstats.free_dquots, |
1744 | .maxlen = sizeof(int), |
1745 | .mode = 0444, |
1746 | .proc_handler = &proc_dointvec, |
1747 | }, |
1748 | { |
1749 | .ctl_name = FS_DQ_SYNCS, |
1750 | .procname = "syncs", |
1751 | .data = &dqstats.syncs, |
1752 | .maxlen = sizeof(int), |
1753 | .mode = 0444, |
1754 | .proc_handler = &proc_dointvec, |
1755 | }, |
1756 | { |
1757 | .ctl_name = FS_DQ_WARNINGS, |
1758 | .procname = "warnings", |
1759 | .data = &flag_print_warnings, |
1760 | .maxlen = sizeof(int), |
1761 | .mode = 0644, |
1762 | .proc_handler = &proc_dointvec, |
1763 | }, |
1764 | { .ctl_name = 0 }, |
1765 | }; |
1766 | |
1767 | static ctl_table fs_table[] = { |
1768 | { |
1769 | .ctl_name = FS_DQSTATS, |
1770 | .procname = "quota", |
1771 | .mode = 0555, |
1772 | .child = fs_dqstats_table, |
1773 | }, |
1774 | { .ctl_name = 0 }, |
1775 | }; |
1776 | |
1777 | static ctl_table sys_table[] = { |
1778 | { |
1779 | .ctl_name = CTL_FS, |
1780 | .procname = "fs", |
1781 | .mode = 0555, |
1782 | .child = fs_table, |
1783 | }, |
1784 | { .ctl_name = 0 }, |
1785 | }; |
1786 | |
1787 | static int __init dquot_init(void) |
1788 | { |
1789 | int i; |
1790 | unsigned long nr_hash, order; |
1791 | |
1792 | printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); |
1793 | |
1794 | register_sysctl_table(sys_table, 0); |
1795 | |
1796 | dquot_cachep = kmem_cache_create("dquot", |
1797 | sizeof(struct dquot), sizeof(unsigned long) * 4, |
1798 | SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|SLAB_PANIC, |
1799 | NULL, NULL); |
1800 | |
1801 | order = 0; |
1802 | dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); |
1803 | if (!dquot_hash) |
1804 | panic("Cannot create dquot hash table"); |
1805 | |
1806 | /* Find power-of-two hlist_heads which can fit into allocation */ |
1807 | nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); |
1808 | dq_hash_bits = 0; |
1809 | do { |
1810 | dq_hash_bits++; |
1811 | } while (nr_hash >> dq_hash_bits); |
1812 | dq_hash_bits--; |
1813 | |
1814 | nr_hash = 1UL << dq_hash_bits; |
1815 | dq_hash_mask = nr_hash - 1; |
1816 | for (i = 0; i < nr_hash; i++) |
1817 | INIT_HLIST_HEAD(dquot_hash + i); |
1818 | |
1819 | printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", |
1820 | nr_hash, order, (PAGE_SIZE << order)); |
1821 | |
1822 | set_shrinker(DEFAULT_SEEKS, shrink_dqcache_memory); |
1823 | |
1824 | return 0; |
1825 | } |
1826 | module_init(dquot_init); |
1827 | |
1828 | EXPORT_SYMBOL(register_quota_format); |
1829 | EXPORT_SYMBOL(unregister_quota_format); |
1830 | EXPORT_SYMBOL(dqstats); |
1831 | EXPORT_SYMBOL(dq_data_lock); |
1832 | EXPORT_SYMBOL(vfs_quota_on); |
1833 | EXPORT_SYMBOL(vfs_quota_on_mount); |
1834 | EXPORT_SYMBOL(vfs_quota_off); |
1835 | EXPORT_SYMBOL(vfs_quota_sync); |
1836 | EXPORT_SYMBOL(vfs_get_dqinfo); |
1837 | EXPORT_SYMBOL(vfs_set_dqinfo); |
1838 | EXPORT_SYMBOL(vfs_get_dqblk); |
1839 | EXPORT_SYMBOL(vfs_set_dqblk); |
1840 | EXPORT_SYMBOL(dquot_commit); |
1841 | EXPORT_SYMBOL(dquot_commit_info); |
1842 | EXPORT_SYMBOL(dquot_acquire); |
1843 | EXPORT_SYMBOL(dquot_release); |
1844 | EXPORT_SYMBOL(dquot_mark_dquot_dirty); |
1845 | EXPORT_SYMBOL(dquot_initialize); |
1846 | EXPORT_SYMBOL(dquot_drop); |
1847 | EXPORT_SYMBOL(dquot_alloc_space); |
1848 | EXPORT_SYMBOL(dquot_alloc_inode); |
1849 | EXPORT_SYMBOL(dquot_free_space); |
1850 | EXPORT_SYMBOL(dquot_free_inode); |
1851 | EXPORT_SYMBOL(dquot_transfer); |