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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 | * Author: Marco van Wieringen <mvw@planets.elm.net> |
13 | * |
14 | * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96 |
15 | * |
16 | * Revised list management to avoid races |
17 | * -- Bill Hawes, <whawes@star.net>, 9/98 |
18 | * |
19 | * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...(). |
20 | * As the consequence the locking was moved from dquot_decr_...(), |
21 | * dquot_incr_...() to calling functions. |
22 | * invalidate_dquots() now writes modified dquots. |
23 | * Serialized quota_off() and quota_on() for mount point. |
24 | * Fixed a few bugs in grow_dquots(). |
25 | * Fixed deadlock in write_dquot() - we no longer account quotas on |
26 | * quota files |
27 | * remove_dquot_ref() moved to inode.c - it now traverses through inodes |
28 | * add_dquot_ref() restarts after blocking |
29 | * Added check for bogus uid and fixed check for group in quotactl. |
30 | * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99 |
31 | * |
32 | * Used struct list_head instead of own list struct |
33 | * Invalidation of referenced dquots is no longer possible |
34 | * Improved free_dquots list management |
35 | * Quota and i_blocks are now updated in one place to avoid races |
36 | * Warnings are now delayed so we won't block in critical section |
37 | * Write updated not to require dquot lock |
38 | * Jan Kara, <jack@suse.cz>, 9/2000 |
39 | * |
40 | * Added dynamic quota structure allocation |
41 | * Jan Kara <jack@suse.cz> 12/2000 |
42 | * |
43 | * Rewritten quota interface. Implemented new quota format and |
44 | * formats registering. |
45 | * Jan Kara, <jack@suse.cz>, 2001,2002 |
46 | * |
47 | * New SMP locking. |
48 | * Jan Kara, <jack@suse.cz>, 10/2002 |
49 | * |
50 | * Added journalled quota support, fix lock inversion problems |
51 | * Jan Kara, <jack@suse.cz>, 2003,2004 |
52 | * |
53 | * (C) Copyright 1994 - 1997 Marco van Wieringen |
54 | */ |
55 | |
56 | #include <linux/errno.h> |
57 | #include <linux/kernel.h> |
58 | #include <linux/fs.h> |
59 | #include <linux/mount.h> |
60 | #include <linux/mm.h> |
61 | #include <linux/time.h> |
62 | #include <linux/types.h> |
63 | #include <linux/string.h> |
64 | #include <linux/fcntl.h> |
65 | #include <linux/stat.h> |
66 | #include <linux/tty.h> |
67 | #include <linux/file.h> |
68 | #include <linux/slab.h> |
69 | #include <linux/sysctl.h> |
70 | #include <linux/init.h> |
71 | #include <linux/module.h> |
72 | #include <linux/proc_fs.h> |
73 | #include <linux/security.h> |
74 | #include <linux/kmod.h> |
75 | #include <linux/namei.h> |
76 | #include <linux/buffer_head.h> |
77 | #include <linux/capability.h> |
78 | #include <linux/quotaops.h> |
79 | #include <linux/writeback.h> /* for inode_lock, oddly enough.. */ |
80 | |
81 | #include <asm/uaccess.h> |
82 | |
83 | #define __DQUOT_PARANOIA |
84 | |
85 | /* |
86 | * There are three quota SMP locks. dq_list_lock protects all lists with quotas |
87 | * and quota formats, dqstats structure containing statistics about the lists |
88 | * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and |
89 | * 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(). dq_state_lock protects |
92 | * modifications of quota state (on quotaon and quotaoff) and readers who care |
93 | * about latest values take it as well. |
94 | * |
95 | * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock, |
96 | * dq_list_lock > dq_state_lock |
97 | * |
98 | * Note that some things (eg. sb pointer, type, id) doesn't change during |
99 | * the life of the dquot structure and so needn't to be protected by a lock |
100 | * |
101 | * Any operation working on dquots via inode pointers must hold dqptr_sem. If |
102 | * operation is just reading pointers from inode (or not using them at all) the |
103 | * read lock is enough. If pointers are altered function must hold write lock. |
104 | * Special care needs to be taken about S_NOQUOTA inode flag (marking that |
105 | * inode is a quota file). Functions adding pointers from inode to dquots have |
106 | * to check this flag under dqptr_sem and then (if S_NOQUOTA is not set) they |
107 | * have to do all pointer modifications before dropping dqptr_sem. This makes |
108 | * sure they cannot race with quotaon which first sets S_NOQUOTA flag and |
109 | * then drops all pointers to dquots from an inode. |
110 | * |
111 | * Each dquot has its dq_lock mutex. Locked dquots might not be referenced |
112 | * from inodes (dquot_alloc_space() and such don't check the dq_lock). |
113 | * Currently dquot is locked only when it is being read to memory (or space for |
114 | * it is being allocated) on the first dqget() and when it is being released on |
115 | * the last dqput(). The allocation and release oparations are serialized by |
116 | * the dq_lock and by checking the use count in dquot_release(). Write |
117 | * operations on dquots don't hold dq_lock as they copy data under dq_data_lock |
118 | * spinlock to internal buffers before writing. |
119 | * |
120 | * Lock ordering (including related VFS locks) is the following: |
121 | * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock > |
122 | * dqio_mutex |
123 | * The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem > |
124 | * dqptr_sem. But filesystem has to count with the fact that functions such as |
125 | * dquot_alloc_space() acquire dqptr_sem and they usually have to be called |
126 | * from inside a transaction to keep filesystem consistency after a crash. Also |
127 | * filesystems usually want to do some IO on dquot from ->mark_dirty which is |
128 | * called with dqptr_sem held. |
129 | * i_mutex on quota files is special (it's below dqio_mutex) |
130 | */ |
131 | |
132 | static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock); |
133 | static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock); |
134 | __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock); |
135 | EXPORT_SYMBOL(dq_data_lock); |
136 | |
137 | static char *quotatypes[] = INITQFNAMES; |
138 | static struct quota_format_type *quota_formats; /* List of registered formats */ |
139 | static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES; |
140 | |
141 | /* SLAB cache for dquot structures */ |
142 | static struct kmem_cache *dquot_cachep; |
143 | |
144 | int register_quota_format(struct quota_format_type *fmt) |
145 | { |
146 | spin_lock(&dq_list_lock); |
147 | fmt->qf_next = quota_formats; |
148 | quota_formats = fmt; |
149 | spin_unlock(&dq_list_lock); |
150 | return 0; |
151 | } |
152 | EXPORT_SYMBOL(register_quota_format); |
153 | |
154 | void unregister_quota_format(struct quota_format_type *fmt) |
155 | { |
156 | struct quota_format_type **actqf; |
157 | |
158 | spin_lock(&dq_list_lock); |
159 | for (actqf = "a_formats; *actqf && *actqf != fmt; |
160 | actqf = &(*actqf)->qf_next) |
161 | ; |
162 | if (*actqf) |
163 | *actqf = (*actqf)->qf_next; |
164 | spin_unlock(&dq_list_lock); |
165 | } |
166 | EXPORT_SYMBOL(unregister_quota_format); |
167 | |
168 | static struct quota_format_type *find_quota_format(int id) |
169 | { |
170 | struct quota_format_type *actqf; |
171 | |
172 | spin_lock(&dq_list_lock); |
173 | for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; |
174 | actqf = actqf->qf_next) |
175 | ; |
176 | if (!actqf || !try_module_get(actqf->qf_owner)) { |
177 | int qm; |
178 | |
179 | spin_unlock(&dq_list_lock); |
180 | |
181 | for (qm = 0; module_names[qm].qm_fmt_id && |
182 | module_names[qm].qm_fmt_id != id; qm++) |
183 | ; |
184 | if (!module_names[qm].qm_fmt_id || |
185 | request_module(module_names[qm].qm_mod_name)) |
186 | return NULL; |
187 | |
188 | spin_lock(&dq_list_lock); |
189 | for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; |
190 | actqf = actqf->qf_next) |
191 | ; |
192 | if (actqf && !try_module_get(actqf->qf_owner)) |
193 | actqf = NULL; |
194 | } |
195 | spin_unlock(&dq_list_lock); |
196 | return actqf; |
197 | } |
198 | |
199 | static void put_quota_format(struct quota_format_type *fmt) |
200 | { |
201 | module_put(fmt->qf_owner); |
202 | } |
203 | |
204 | /* |
205 | * Dquot List Management: |
206 | * The quota code uses three lists for dquot management: the inuse_list, |
207 | * free_dquots, and dquot_hash[] array. A single dquot structure may be |
208 | * on all three lists, depending on its current state. |
209 | * |
210 | * All dquots are placed to the end of inuse_list when first created, and this |
211 | * list is used for invalidate operation, which must look at every dquot. |
212 | * |
213 | * Unused dquots (dq_count == 0) are added to the free_dquots list when freed, |
214 | * and this list is searched whenever we need an available dquot. Dquots are |
215 | * removed from the list as soon as they are used again, and |
216 | * dqstats.free_dquots gives the number of dquots on the list. When |
217 | * dquot is invalidated it's completely released from memory. |
218 | * |
219 | * Dquots with a specific identity (device, type and id) are placed on |
220 | * one of the dquot_hash[] hash chains. The provides an efficient search |
221 | * mechanism to locate a specific dquot. |
222 | */ |
223 | |
224 | static LIST_HEAD(inuse_list); |
225 | static LIST_HEAD(free_dquots); |
226 | static unsigned int dq_hash_bits, dq_hash_mask; |
227 | static struct hlist_head *dquot_hash; |
228 | |
229 | struct dqstats dqstats; |
230 | EXPORT_SYMBOL(dqstats); |
231 | |
232 | static qsize_t inode_get_rsv_space(struct inode *inode); |
233 | static void __dquot_initialize(struct inode *inode, int type); |
234 | |
235 | static inline unsigned int |
236 | hashfn(const struct super_block *sb, unsigned int id, int type) |
237 | { |
238 | unsigned long tmp; |
239 | |
240 | tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type); |
241 | return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask; |
242 | } |
243 | |
244 | /* |
245 | * Following list functions expect dq_list_lock to be held |
246 | */ |
247 | static inline void insert_dquot_hash(struct dquot *dquot) |
248 | { |
249 | struct hlist_head *head; |
250 | head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type); |
251 | hlist_add_head(&dquot->dq_hash, head); |
252 | } |
253 | |
254 | static inline void remove_dquot_hash(struct dquot *dquot) |
255 | { |
256 | hlist_del_init(&dquot->dq_hash); |
257 | } |
258 | |
259 | static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, |
260 | unsigned int id, int type) |
261 | { |
262 | struct hlist_node *node; |
263 | struct dquot *dquot; |
264 | |
265 | hlist_for_each (node, dquot_hash+hashent) { |
266 | dquot = hlist_entry(node, struct dquot, dq_hash); |
267 | if (dquot->dq_sb == sb && dquot->dq_id == id && |
268 | dquot->dq_type == type) |
269 | return dquot; |
270 | } |
271 | return NULL; |
272 | } |
273 | |
274 | /* Add a dquot to the tail of the free list */ |
275 | static inline void put_dquot_last(struct dquot *dquot) |
276 | { |
277 | list_add_tail(&dquot->dq_free, &free_dquots); |
278 | dqstats.free_dquots++; |
279 | } |
280 | |
281 | static inline void remove_free_dquot(struct dquot *dquot) |
282 | { |
283 | if (list_empty(&dquot->dq_free)) |
284 | return; |
285 | list_del_init(&dquot->dq_free); |
286 | dqstats.free_dquots--; |
287 | } |
288 | |
289 | static inline void put_inuse(struct dquot *dquot) |
290 | { |
291 | /* We add to the back of inuse list so we don't have to restart |
292 | * when traversing this list and we block */ |
293 | list_add_tail(&dquot->dq_inuse, &inuse_list); |
294 | dqstats.allocated_dquots++; |
295 | } |
296 | |
297 | static inline void remove_inuse(struct dquot *dquot) |
298 | { |
299 | dqstats.allocated_dquots--; |
300 | list_del(&dquot->dq_inuse); |
301 | } |
302 | /* |
303 | * End of list functions needing dq_list_lock |
304 | */ |
305 | |
306 | static void wait_on_dquot(struct dquot *dquot) |
307 | { |
308 | mutex_lock(&dquot->dq_lock); |
309 | mutex_unlock(&dquot->dq_lock); |
310 | } |
311 | |
312 | static inline int dquot_dirty(struct dquot *dquot) |
313 | { |
314 | return test_bit(DQ_MOD_B, &dquot->dq_flags); |
315 | } |
316 | |
317 | static inline int mark_dquot_dirty(struct dquot *dquot) |
318 | { |
319 | return dquot->dq_sb->dq_op->mark_dirty(dquot); |
320 | } |
321 | |
322 | int dquot_mark_dquot_dirty(struct dquot *dquot) |
323 | { |
324 | spin_lock(&dq_list_lock); |
325 | if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) |
326 | list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)-> |
327 | info[dquot->dq_type].dqi_dirty_list); |
328 | spin_unlock(&dq_list_lock); |
329 | return 0; |
330 | } |
331 | EXPORT_SYMBOL(dquot_mark_dquot_dirty); |
332 | |
333 | /* Dirtify all the dquots - this can block when journalling */ |
334 | static inline int mark_all_dquot_dirty(struct dquot * const *dquot) |
335 | { |
336 | int ret, err, cnt; |
337 | |
338 | ret = err = 0; |
339 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
340 | if (dquot[cnt]) |
341 | /* Even in case of error we have to continue */ |
342 | ret = mark_dquot_dirty(dquot[cnt]); |
343 | if (!err) |
344 | err = ret; |
345 | } |
346 | return err; |
347 | } |
348 | |
349 | static inline void dqput_all(struct dquot **dquot) |
350 | { |
351 | unsigned int cnt; |
352 | |
353 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
354 | dqput(dquot[cnt]); |
355 | } |
356 | |
357 | /* This function needs dq_list_lock */ |
358 | static inline int clear_dquot_dirty(struct dquot *dquot) |
359 | { |
360 | if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) |
361 | return 0; |
362 | list_del_init(&dquot->dq_dirty); |
363 | return 1; |
364 | } |
365 | |
366 | void mark_info_dirty(struct super_block *sb, int type) |
367 | { |
368 | set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags); |
369 | } |
370 | EXPORT_SYMBOL(mark_info_dirty); |
371 | |
372 | /* |
373 | * Read dquot from disk and alloc space for it |
374 | */ |
375 | |
376 | int dquot_acquire(struct dquot *dquot) |
377 | { |
378 | int ret = 0, ret2 = 0; |
379 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); |
380 | |
381 | mutex_lock(&dquot->dq_lock); |
382 | mutex_lock(&dqopt->dqio_mutex); |
383 | if (!test_bit(DQ_READ_B, &dquot->dq_flags)) |
384 | ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot); |
385 | if (ret < 0) |
386 | goto out_iolock; |
387 | set_bit(DQ_READ_B, &dquot->dq_flags); |
388 | /* Instantiate dquot if needed */ |
389 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) { |
390 | ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); |
391 | /* Write the info if needed */ |
392 | if (info_dirty(&dqopt->info[dquot->dq_type])) { |
393 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info( |
394 | dquot->dq_sb, dquot->dq_type); |
395 | } |
396 | if (ret < 0) |
397 | goto out_iolock; |
398 | if (ret2 < 0) { |
399 | ret = ret2; |
400 | goto out_iolock; |
401 | } |
402 | } |
403 | set_bit(DQ_ACTIVE_B, &dquot->dq_flags); |
404 | out_iolock: |
405 | mutex_unlock(&dqopt->dqio_mutex); |
406 | mutex_unlock(&dquot->dq_lock); |
407 | return ret; |
408 | } |
409 | EXPORT_SYMBOL(dquot_acquire); |
410 | |
411 | /* |
412 | * Write dquot to disk |
413 | */ |
414 | int dquot_commit(struct dquot *dquot) |
415 | { |
416 | int ret = 0, ret2 = 0; |
417 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); |
418 | |
419 | mutex_lock(&dqopt->dqio_mutex); |
420 | spin_lock(&dq_list_lock); |
421 | if (!clear_dquot_dirty(dquot)) { |
422 | spin_unlock(&dq_list_lock); |
423 | goto out_sem; |
424 | } |
425 | spin_unlock(&dq_list_lock); |
426 | /* Inactive dquot can be only if there was error during read/init |
427 | * => we have better not writing it */ |
428 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { |
429 | ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); |
430 | if (info_dirty(&dqopt->info[dquot->dq_type])) { |
431 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info( |
432 | dquot->dq_sb, dquot->dq_type); |
433 | } |
434 | if (ret >= 0) |
435 | ret = ret2; |
436 | } |
437 | out_sem: |
438 | mutex_unlock(&dqopt->dqio_mutex); |
439 | return ret; |
440 | } |
441 | EXPORT_SYMBOL(dquot_commit); |
442 | |
443 | /* |
444 | * Release dquot |
445 | */ |
446 | int dquot_release(struct dquot *dquot) |
447 | { |
448 | int ret = 0, ret2 = 0; |
449 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); |
450 | |
451 | mutex_lock(&dquot->dq_lock); |
452 | /* Check whether we are not racing with some other dqget() */ |
453 | if (atomic_read(&dquot->dq_count) > 1) |
454 | goto out_dqlock; |
455 | mutex_lock(&dqopt->dqio_mutex); |
456 | if (dqopt->ops[dquot->dq_type]->release_dqblk) { |
457 | ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot); |
458 | /* Write the info */ |
459 | if (info_dirty(&dqopt->info[dquot->dq_type])) { |
460 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info( |
461 | dquot->dq_sb, dquot->dq_type); |
462 | } |
463 | if (ret >= 0) |
464 | ret = ret2; |
465 | } |
466 | clear_bit(DQ_ACTIVE_B, &dquot->dq_flags); |
467 | mutex_unlock(&dqopt->dqio_mutex); |
468 | out_dqlock: |
469 | mutex_unlock(&dquot->dq_lock); |
470 | return ret; |
471 | } |
472 | EXPORT_SYMBOL(dquot_release); |
473 | |
474 | void dquot_destroy(struct dquot *dquot) |
475 | { |
476 | kmem_cache_free(dquot_cachep, dquot); |
477 | } |
478 | EXPORT_SYMBOL(dquot_destroy); |
479 | |
480 | static inline void do_destroy_dquot(struct dquot *dquot) |
481 | { |
482 | dquot->dq_sb->dq_op->destroy_dquot(dquot); |
483 | } |
484 | |
485 | /* Invalidate all dquots on the list. Note that this function is called after |
486 | * quota is disabled and pointers from inodes removed so there cannot be new |
487 | * quota users. There can still be some users of quotas due to inodes being |
488 | * just deleted or pruned by prune_icache() (those are not attached to any |
489 | * list) or parallel quotactl call. We have to wait for such users. |
490 | */ |
491 | static void invalidate_dquots(struct super_block *sb, int type) |
492 | { |
493 | struct dquot *dquot, *tmp; |
494 | |
495 | restart: |
496 | spin_lock(&dq_list_lock); |
497 | list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) { |
498 | if (dquot->dq_sb != sb) |
499 | continue; |
500 | if (dquot->dq_type != type) |
501 | continue; |
502 | /* Wait for dquot users */ |
503 | if (atomic_read(&dquot->dq_count)) { |
504 | DEFINE_WAIT(wait); |
505 | |
506 | atomic_inc(&dquot->dq_count); |
507 | prepare_to_wait(&dquot->dq_wait_unused, &wait, |
508 | TASK_UNINTERRUPTIBLE); |
509 | spin_unlock(&dq_list_lock); |
510 | /* Once dqput() wakes us up, we know it's time to free |
511 | * the dquot. |
512 | * IMPORTANT: we rely on the fact that there is always |
513 | * at most one process waiting for dquot to free. |
514 | * Otherwise dq_count would be > 1 and we would never |
515 | * wake up. |
516 | */ |
517 | if (atomic_read(&dquot->dq_count) > 1) |
518 | schedule(); |
519 | finish_wait(&dquot->dq_wait_unused, &wait); |
520 | dqput(dquot); |
521 | /* At this moment dquot() need not exist (it could be |
522 | * reclaimed by prune_dqcache(). Hence we must |
523 | * restart. */ |
524 | goto restart; |
525 | } |
526 | /* |
527 | * Quota now has no users and it has been written on last |
528 | * dqput() |
529 | */ |
530 | remove_dquot_hash(dquot); |
531 | remove_free_dquot(dquot); |
532 | remove_inuse(dquot); |
533 | do_destroy_dquot(dquot); |
534 | } |
535 | spin_unlock(&dq_list_lock); |
536 | } |
537 | |
538 | /* Call callback for every active dquot on given filesystem */ |
539 | int dquot_scan_active(struct super_block *sb, |
540 | int (*fn)(struct dquot *dquot, unsigned long priv), |
541 | unsigned long priv) |
542 | { |
543 | struct dquot *dquot, *old_dquot = NULL; |
544 | int ret = 0; |
545 | |
546 | mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); |
547 | spin_lock(&dq_list_lock); |
548 | list_for_each_entry(dquot, &inuse_list, dq_inuse) { |
549 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) |
550 | continue; |
551 | if (dquot->dq_sb != sb) |
552 | continue; |
553 | /* Now we have active dquot so we can just increase use count */ |
554 | atomic_inc(&dquot->dq_count); |
555 | dqstats.lookups++; |
556 | spin_unlock(&dq_list_lock); |
557 | dqput(old_dquot); |
558 | old_dquot = dquot; |
559 | ret = fn(dquot, priv); |
560 | if (ret < 0) |
561 | goto out; |
562 | spin_lock(&dq_list_lock); |
563 | /* We are safe to continue now because our dquot could not |
564 | * be moved out of the inuse list while we hold the reference */ |
565 | } |
566 | spin_unlock(&dq_list_lock); |
567 | out: |
568 | dqput(old_dquot); |
569 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
570 | return ret; |
571 | } |
572 | EXPORT_SYMBOL(dquot_scan_active); |
573 | |
574 | int vfs_quota_sync(struct super_block *sb, int type, int wait) |
575 | { |
576 | struct list_head *dirty; |
577 | struct dquot *dquot; |
578 | struct quota_info *dqopt = sb_dqopt(sb); |
579 | int cnt; |
580 | |
581 | mutex_lock(&dqopt->dqonoff_mutex); |
582 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
583 | if (type != -1 && cnt != type) |
584 | continue; |
585 | if (!sb_has_quota_active(sb, cnt)) |
586 | continue; |
587 | spin_lock(&dq_list_lock); |
588 | dirty = &dqopt->info[cnt].dqi_dirty_list; |
589 | while (!list_empty(dirty)) { |
590 | dquot = list_first_entry(dirty, struct dquot, |
591 | dq_dirty); |
592 | /* Dirty and inactive can be only bad dquot... */ |
593 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { |
594 | clear_dquot_dirty(dquot); |
595 | continue; |
596 | } |
597 | /* Now we have active dquot from which someone is |
598 | * holding reference so we can safely just increase |
599 | * use count */ |
600 | atomic_inc(&dquot->dq_count); |
601 | dqstats.lookups++; |
602 | spin_unlock(&dq_list_lock); |
603 | sb->dq_op->write_dquot(dquot); |
604 | dqput(dquot); |
605 | spin_lock(&dq_list_lock); |
606 | } |
607 | spin_unlock(&dq_list_lock); |
608 | } |
609 | |
610 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
611 | if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt) |
612 | && info_dirty(&dqopt->info[cnt])) |
613 | sb->dq_op->write_info(sb, cnt); |
614 | spin_lock(&dq_list_lock); |
615 | dqstats.syncs++; |
616 | spin_unlock(&dq_list_lock); |
617 | mutex_unlock(&dqopt->dqonoff_mutex); |
618 | |
619 | if (!wait || (sb_dqopt(sb)->flags & DQUOT_QUOTA_SYS_FILE)) |
620 | return 0; |
621 | |
622 | /* This is not very clever (and fast) but currently I don't know about |
623 | * any other simple way of getting quota data to disk and we must get |
624 | * them there for userspace to be visible... */ |
625 | if (sb->s_op->sync_fs) |
626 | sb->s_op->sync_fs(sb, 1); |
627 | sync_blockdev(sb->s_bdev); |
628 | |
629 | /* |
630 | * Now when everything is written we can discard the pagecache so |
631 | * that userspace sees the changes. |
632 | */ |
633 | mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); |
634 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
635 | if (type != -1 && cnt != type) |
636 | continue; |
637 | if (!sb_has_quota_active(sb, cnt)) |
638 | continue; |
639 | mutex_lock_nested(&sb_dqopt(sb)->files[cnt]->i_mutex, |
640 | I_MUTEX_QUOTA); |
641 | truncate_inode_pages(&sb_dqopt(sb)->files[cnt]->i_data, 0); |
642 | mutex_unlock(&sb_dqopt(sb)->files[cnt]->i_mutex); |
643 | } |
644 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
645 | |
646 | return 0; |
647 | } |
648 | EXPORT_SYMBOL(vfs_quota_sync); |
649 | |
650 | /* Free unused dquots from cache */ |
651 | static void prune_dqcache(int count) |
652 | { |
653 | struct list_head *head; |
654 | struct dquot *dquot; |
655 | |
656 | head = free_dquots.prev; |
657 | while (head != &free_dquots && count) { |
658 | dquot = list_entry(head, struct dquot, dq_free); |
659 | remove_dquot_hash(dquot); |
660 | remove_free_dquot(dquot); |
661 | remove_inuse(dquot); |
662 | do_destroy_dquot(dquot); |
663 | count--; |
664 | head = free_dquots.prev; |
665 | } |
666 | } |
667 | |
668 | /* |
669 | * This is called from kswapd when we think we need some |
670 | * more memory |
671 | */ |
672 | |
673 | static int shrink_dqcache_memory(int nr, gfp_t gfp_mask) |
674 | { |
675 | if (nr) { |
676 | spin_lock(&dq_list_lock); |
677 | prune_dqcache(nr); |
678 | spin_unlock(&dq_list_lock); |
679 | } |
680 | return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure; |
681 | } |
682 | |
683 | static struct shrinker dqcache_shrinker = { |
684 | .shrink = shrink_dqcache_memory, |
685 | .seeks = DEFAULT_SEEKS, |
686 | }; |
687 | |
688 | /* |
689 | * Put reference to dquot |
690 | * NOTE: If you change this function please check whether dqput_blocks() works right... |
691 | */ |
692 | void dqput(struct dquot *dquot) |
693 | { |
694 | int ret; |
695 | |
696 | if (!dquot) |
697 | return; |
698 | #ifdef __DQUOT_PARANOIA |
699 | if (!atomic_read(&dquot->dq_count)) { |
700 | printk("VFS: dqput: trying to free free dquot\n"); |
701 | printk("VFS: device %s, dquot of %s %d\n", |
702 | dquot->dq_sb->s_id, |
703 | quotatypes[dquot->dq_type], |
704 | dquot->dq_id); |
705 | BUG(); |
706 | } |
707 | #endif |
708 | |
709 | spin_lock(&dq_list_lock); |
710 | dqstats.drops++; |
711 | spin_unlock(&dq_list_lock); |
712 | we_slept: |
713 | spin_lock(&dq_list_lock); |
714 | if (atomic_read(&dquot->dq_count) > 1) { |
715 | /* We have more than one user... nothing to do */ |
716 | atomic_dec(&dquot->dq_count); |
717 | /* Releasing dquot during quotaoff phase? */ |
718 | if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) && |
719 | atomic_read(&dquot->dq_count) == 1) |
720 | wake_up(&dquot->dq_wait_unused); |
721 | spin_unlock(&dq_list_lock); |
722 | return; |
723 | } |
724 | /* Need to release dquot? */ |
725 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { |
726 | spin_unlock(&dq_list_lock); |
727 | /* Commit dquot before releasing */ |
728 | ret = dquot->dq_sb->dq_op->write_dquot(dquot); |
729 | if (ret < 0) { |
730 | printk(KERN_ERR "VFS: cannot write quota structure on " |
731 | "device %s (error %d). Quota may get out of " |
732 | "sync!\n", dquot->dq_sb->s_id, ret); |
733 | /* |
734 | * We clear dirty bit anyway, so that we avoid |
735 | * infinite loop here |
736 | */ |
737 | spin_lock(&dq_list_lock); |
738 | clear_dquot_dirty(dquot); |
739 | spin_unlock(&dq_list_lock); |
740 | } |
741 | goto we_slept; |
742 | } |
743 | /* Clear flag in case dquot was inactive (something bad happened) */ |
744 | clear_dquot_dirty(dquot); |
745 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { |
746 | spin_unlock(&dq_list_lock); |
747 | dquot->dq_sb->dq_op->release_dquot(dquot); |
748 | goto we_slept; |
749 | } |
750 | atomic_dec(&dquot->dq_count); |
751 | #ifdef __DQUOT_PARANOIA |
752 | /* sanity check */ |
753 | BUG_ON(!list_empty(&dquot->dq_free)); |
754 | #endif |
755 | put_dquot_last(dquot); |
756 | spin_unlock(&dq_list_lock); |
757 | } |
758 | EXPORT_SYMBOL(dqput); |
759 | |
760 | struct dquot *dquot_alloc(struct super_block *sb, int type) |
761 | { |
762 | return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); |
763 | } |
764 | EXPORT_SYMBOL(dquot_alloc); |
765 | |
766 | static struct dquot *get_empty_dquot(struct super_block *sb, int type) |
767 | { |
768 | struct dquot *dquot; |
769 | |
770 | dquot = sb->dq_op->alloc_dquot(sb, type); |
771 | if(!dquot) |
772 | return NULL; |
773 | |
774 | mutex_init(&dquot->dq_lock); |
775 | INIT_LIST_HEAD(&dquot->dq_free); |
776 | INIT_LIST_HEAD(&dquot->dq_inuse); |
777 | INIT_HLIST_NODE(&dquot->dq_hash); |
778 | INIT_LIST_HEAD(&dquot->dq_dirty); |
779 | init_waitqueue_head(&dquot->dq_wait_unused); |
780 | dquot->dq_sb = sb; |
781 | dquot->dq_type = type; |
782 | atomic_set(&dquot->dq_count, 1); |
783 | |
784 | return dquot; |
785 | } |
786 | |
787 | /* |
788 | * Get reference to dquot |
789 | * |
790 | * Locking is slightly tricky here. We are guarded from parallel quotaoff() |
791 | * destroying our dquot by: |
792 | * a) checking for quota flags under dq_list_lock and |
793 | * b) getting a reference to dquot before we release dq_list_lock |
794 | */ |
795 | struct dquot *dqget(struct super_block *sb, unsigned int id, int type) |
796 | { |
797 | unsigned int hashent = hashfn(sb, id, type); |
798 | struct dquot *dquot = NULL, *empty = NULL; |
799 | |
800 | if (!sb_has_quota_active(sb, type)) |
801 | return NULL; |
802 | we_slept: |
803 | spin_lock(&dq_list_lock); |
804 | spin_lock(&dq_state_lock); |
805 | if (!sb_has_quota_active(sb, type)) { |
806 | spin_unlock(&dq_state_lock); |
807 | spin_unlock(&dq_list_lock); |
808 | goto out; |
809 | } |
810 | spin_unlock(&dq_state_lock); |
811 | |
812 | dquot = find_dquot(hashent, sb, id, type); |
813 | if (!dquot) { |
814 | if (!empty) { |
815 | spin_unlock(&dq_list_lock); |
816 | empty = get_empty_dquot(sb, type); |
817 | if (!empty) |
818 | schedule(); /* Try to wait for a moment... */ |
819 | goto we_slept; |
820 | } |
821 | dquot = empty; |
822 | empty = NULL; |
823 | dquot->dq_id = id; |
824 | /* all dquots go on the inuse_list */ |
825 | put_inuse(dquot); |
826 | /* hash it first so it can be found */ |
827 | insert_dquot_hash(dquot); |
828 | dqstats.lookups++; |
829 | spin_unlock(&dq_list_lock); |
830 | } else { |
831 | if (!atomic_read(&dquot->dq_count)) |
832 | remove_free_dquot(dquot); |
833 | atomic_inc(&dquot->dq_count); |
834 | dqstats.cache_hits++; |
835 | dqstats.lookups++; |
836 | spin_unlock(&dq_list_lock); |
837 | } |
838 | /* Wait for dq_lock - after this we know that either dquot_release() is |
839 | * already finished or it will be canceled due to dq_count > 1 test */ |
840 | wait_on_dquot(dquot); |
841 | /* Read the dquot / allocate space in quota file */ |
842 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && |
843 | sb->dq_op->acquire_dquot(dquot) < 0) { |
844 | dqput(dquot); |
845 | dquot = NULL; |
846 | goto out; |
847 | } |
848 | #ifdef __DQUOT_PARANOIA |
849 | BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ |
850 | #endif |
851 | out: |
852 | if (empty) |
853 | do_destroy_dquot(empty); |
854 | |
855 | return dquot; |
856 | } |
857 | EXPORT_SYMBOL(dqget); |
858 | |
859 | static int dqinit_needed(struct inode *inode, int type) |
860 | { |
861 | int cnt; |
862 | |
863 | if (IS_NOQUOTA(inode)) |
864 | return 0; |
865 | if (type != -1) |
866 | return !inode->i_dquot[type]; |
867 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
868 | if (!inode->i_dquot[cnt]) |
869 | return 1; |
870 | return 0; |
871 | } |
872 | |
873 | /* This routine is guarded by dqonoff_mutex mutex */ |
874 | static void add_dquot_ref(struct super_block *sb, int type) |
875 | { |
876 | struct inode *inode, *old_inode = NULL; |
877 | #ifdef __DQUOT_PARANOIA |
878 | int reserved = 0; |
879 | #endif |
880 | |
881 | spin_lock(&inode_lock); |
882 | list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { |
883 | if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE|I_NEW)) |
884 | continue; |
885 | #ifdef __DQUOT_PARANOIA |
886 | if (unlikely(inode_get_rsv_space(inode) > 0)) |
887 | reserved = 1; |
888 | #endif |
889 | if (!atomic_read(&inode->i_writecount)) |
890 | continue; |
891 | if (!dqinit_needed(inode, type)) |
892 | continue; |
893 | |
894 | __iget(inode); |
895 | spin_unlock(&inode_lock); |
896 | |
897 | iput(old_inode); |
898 | __dquot_initialize(inode, type); |
899 | /* We hold a reference to 'inode' so it couldn't have been |
900 | * removed from s_inodes list while we dropped the inode_lock. |
901 | * We cannot iput the inode now as we can be holding the last |
902 | * reference and we cannot iput it under inode_lock. So we |
903 | * keep the reference and iput it later. */ |
904 | old_inode = inode; |
905 | spin_lock(&inode_lock); |
906 | } |
907 | spin_unlock(&inode_lock); |
908 | iput(old_inode); |
909 | |
910 | #ifdef __DQUOT_PARANOIA |
911 | if (reserved) { |
912 | printk(KERN_WARNING "VFS (%s): Writes happened before quota" |
913 | " was turned on thus quota information is probably " |
914 | "inconsistent. Please run quotacheck(8).\n", sb->s_id); |
915 | } |
916 | #endif |
917 | } |
918 | |
919 | /* |
920 | * Return 0 if dqput() won't block. |
921 | * (note that 1 doesn't necessarily mean blocking) |
922 | */ |
923 | static inline int dqput_blocks(struct dquot *dquot) |
924 | { |
925 | if (atomic_read(&dquot->dq_count) <= 1) |
926 | return 1; |
927 | return 0; |
928 | } |
929 | |
930 | /* |
931 | * Remove references to dquots from inode and add dquot to list for freeing |
932 | * if we have the last referece to dquot |
933 | * We can't race with anybody because we hold dqptr_sem for writing... |
934 | */ |
935 | static int remove_inode_dquot_ref(struct inode *inode, int type, |
936 | struct list_head *tofree_head) |
937 | { |
938 | struct dquot *dquot = inode->i_dquot[type]; |
939 | |
940 | inode->i_dquot[type] = NULL; |
941 | if (dquot) { |
942 | if (dqput_blocks(dquot)) { |
943 | #ifdef __DQUOT_PARANOIA |
944 | if (atomic_read(&dquot->dq_count) != 1) |
945 | printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count)); |
946 | #endif |
947 | spin_lock(&dq_list_lock); |
948 | /* As dquot must have currently users it can't be on |
949 | * the free list... */ |
950 | list_add(&dquot->dq_free, tofree_head); |
951 | spin_unlock(&dq_list_lock); |
952 | return 1; |
953 | } |
954 | else |
955 | dqput(dquot); /* We have guaranteed we won't block */ |
956 | } |
957 | return 0; |
958 | } |
959 | |
960 | /* |
961 | * Free list of dquots |
962 | * Dquots are removed from inodes and no new references can be got so we are |
963 | * the only ones holding reference |
964 | */ |
965 | static void put_dquot_list(struct list_head *tofree_head) |
966 | { |
967 | struct list_head *act_head; |
968 | struct dquot *dquot; |
969 | |
970 | act_head = tofree_head->next; |
971 | while (act_head != tofree_head) { |
972 | dquot = list_entry(act_head, struct dquot, dq_free); |
973 | act_head = act_head->next; |
974 | /* Remove dquot from the list so we won't have problems... */ |
975 | list_del_init(&dquot->dq_free); |
976 | dqput(dquot); |
977 | } |
978 | } |
979 | |
980 | static void remove_dquot_ref(struct super_block *sb, int type, |
981 | struct list_head *tofree_head) |
982 | { |
983 | struct inode *inode; |
984 | |
985 | spin_lock(&inode_lock); |
986 | list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { |
987 | /* |
988 | * We have to scan also I_NEW inodes because they can already |
989 | * have quota pointer initialized. Luckily, we need to touch |
990 | * only quota pointers and these have separate locking |
991 | * (dqptr_sem). |
992 | */ |
993 | if (!IS_NOQUOTA(inode)) |
994 | remove_inode_dquot_ref(inode, type, tofree_head); |
995 | } |
996 | spin_unlock(&inode_lock); |
997 | } |
998 | |
999 | /* Gather all references from inodes and drop them */ |
1000 | static void drop_dquot_ref(struct super_block *sb, int type) |
1001 | { |
1002 | LIST_HEAD(tofree_head); |
1003 | |
1004 | if (sb->dq_op) { |
1005 | down_write(&sb_dqopt(sb)->dqptr_sem); |
1006 | remove_dquot_ref(sb, type, &tofree_head); |
1007 | up_write(&sb_dqopt(sb)->dqptr_sem); |
1008 | put_dquot_list(&tofree_head); |
1009 | } |
1010 | } |
1011 | |
1012 | static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) |
1013 | { |
1014 | dquot->dq_dqb.dqb_curinodes += number; |
1015 | } |
1016 | |
1017 | static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) |
1018 | { |
1019 | dquot->dq_dqb.dqb_curspace += number; |
1020 | } |
1021 | |
1022 | static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) |
1023 | { |
1024 | dquot->dq_dqb.dqb_rsvspace += number; |
1025 | } |
1026 | |
1027 | /* |
1028 | * Claim reserved quota space |
1029 | */ |
1030 | static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) |
1031 | { |
1032 | if (dquot->dq_dqb.dqb_rsvspace < number) { |
1033 | WARN_ON_ONCE(1); |
1034 | number = dquot->dq_dqb.dqb_rsvspace; |
1035 | } |
1036 | dquot->dq_dqb.dqb_curspace += number; |
1037 | dquot->dq_dqb.dqb_rsvspace -= number; |
1038 | } |
1039 | |
1040 | static inline |
1041 | void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) |
1042 | { |
1043 | if (dquot->dq_dqb.dqb_rsvspace >= number) |
1044 | dquot->dq_dqb.dqb_rsvspace -= number; |
1045 | else { |
1046 | WARN_ON_ONCE(1); |
1047 | dquot->dq_dqb.dqb_rsvspace = 0; |
1048 | } |
1049 | } |
1050 | |
1051 | static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) |
1052 | { |
1053 | if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || |
1054 | dquot->dq_dqb.dqb_curinodes >= number) |
1055 | dquot->dq_dqb.dqb_curinodes -= number; |
1056 | else |
1057 | dquot->dq_dqb.dqb_curinodes = 0; |
1058 | if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) |
1059 | dquot->dq_dqb.dqb_itime = (time_t) 0; |
1060 | clear_bit(DQ_INODES_B, &dquot->dq_flags); |
1061 | } |
1062 | |
1063 | static void dquot_decr_space(struct dquot *dquot, qsize_t number) |
1064 | { |
1065 | if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || |
1066 | dquot->dq_dqb.dqb_curspace >= number) |
1067 | dquot->dq_dqb.dqb_curspace -= number; |
1068 | else |
1069 | dquot->dq_dqb.dqb_curspace = 0; |
1070 | if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) |
1071 | dquot->dq_dqb.dqb_btime = (time_t) 0; |
1072 | clear_bit(DQ_BLKS_B, &dquot->dq_flags); |
1073 | } |
1074 | |
1075 | static int warning_issued(struct dquot *dquot, const int warntype) |
1076 | { |
1077 | int flag = (warntype == QUOTA_NL_BHARDWARN || |
1078 | warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : |
1079 | ((warntype == QUOTA_NL_IHARDWARN || |
1080 | warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); |
1081 | |
1082 | if (!flag) |
1083 | return 0; |
1084 | return test_and_set_bit(flag, &dquot->dq_flags); |
1085 | } |
1086 | |
1087 | #ifdef CONFIG_PRINT_QUOTA_WARNING |
1088 | static int flag_print_warnings = 1; |
1089 | |
1090 | static int need_print_warning(struct dquot *dquot) |
1091 | { |
1092 | if (!flag_print_warnings) |
1093 | return 0; |
1094 | |
1095 | switch (dquot->dq_type) { |
1096 | case USRQUOTA: |
1097 | return current_fsuid() == dquot->dq_id; |
1098 | case GRPQUOTA: |
1099 | return in_group_p(dquot->dq_id); |
1100 | } |
1101 | return 0; |
1102 | } |
1103 | |
1104 | /* Print warning to user which exceeded quota */ |
1105 | static void print_warning(struct dquot *dquot, const int warntype) |
1106 | { |
1107 | char *msg = NULL; |
1108 | struct tty_struct *tty; |
1109 | |
1110 | if (warntype == QUOTA_NL_IHARDBELOW || |
1111 | warntype == QUOTA_NL_ISOFTBELOW || |
1112 | warntype == QUOTA_NL_BHARDBELOW || |
1113 | warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot)) |
1114 | return; |
1115 | |
1116 | tty = get_current_tty(); |
1117 | if (!tty) |
1118 | return; |
1119 | tty_write_message(tty, dquot->dq_sb->s_id); |
1120 | if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) |
1121 | tty_write_message(tty, ": warning, "); |
1122 | else |
1123 | tty_write_message(tty, ": write failed, "); |
1124 | tty_write_message(tty, quotatypes[dquot->dq_type]); |
1125 | switch (warntype) { |
1126 | case QUOTA_NL_IHARDWARN: |
1127 | msg = " file limit reached.\r\n"; |
1128 | break; |
1129 | case QUOTA_NL_ISOFTLONGWARN: |
1130 | msg = " file quota exceeded too long.\r\n"; |
1131 | break; |
1132 | case QUOTA_NL_ISOFTWARN: |
1133 | msg = " file quota exceeded.\r\n"; |
1134 | break; |
1135 | case QUOTA_NL_BHARDWARN: |
1136 | msg = " block limit reached.\r\n"; |
1137 | break; |
1138 | case QUOTA_NL_BSOFTLONGWARN: |
1139 | msg = " block quota exceeded too long.\r\n"; |
1140 | break; |
1141 | case QUOTA_NL_BSOFTWARN: |
1142 | msg = " block quota exceeded.\r\n"; |
1143 | break; |
1144 | } |
1145 | tty_write_message(tty, msg); |
1146 | tty_kref_put(tty); |
1147 | } |
1148 | #endif |
1149 | |
1150 | /* |
1151 | * Write warnings to the console and send warning messages over netlink. |
1152 | * |
1153 | * Note that this function can sleep. |
1154 | */ |
1155 | static void flush_warnings(struct dquot *const *dquots, char *warntype) |
1156 | { |
1157 | struct dquot *dq; |
1158 | int i; |
1159 | |
1160 | for (i = 0; i < MAXQUOTAS; i++) { |
1161 | dq = dquots[i]; |
1162 | if (dq && warntype[i] != QUOTA_NL_NOWARN && |
1163 | !warning_issued(dq, warntype[i])) { |
1164 | #ifdef CONFIG_PRINT_QUOTA_WARNING |
1165 | print_warning(dq, warntype[i]); |
1166 | #endif |
1167 | quota_send_warning(dq->dq_type, dq->dq_id, |
1168 | dq->dq_sb->s_dev, warntype[i]); |
1169 | } |
1170 | } |
1171 | } |
1172 | |
1173 | static int ignore_hardlimit(struct dquot *dquot) |
1174 | { |
1175 | struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; |
1176 | |
1177 | return capable(CAP_SYS_RESOURCE) && |
1178 | (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || |
1179 | !(info->dqi_flags & V1_DQF_RSQUASH)); |
1180 | } |
1181 | |
1182 | /* needs dq_data_lock */ |
1183 | static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) |
1184 | { |
1185 | qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; |
1186 | |
1187 | *warntype = QUOTA_NL_NOWARN; |
1188 | if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || |
1189 | test_bit(DQ_FAKE_B, &dquot->dq_flags)) |
1190 | return 0; |
1191 | |
1192 | if (dquot->dq_dqb.dqb_ihardlimit && |
1193 | newinodes > dquot->dq_dqb.dqb_ihardlimit && |
1194 | !ignore_hardlimit(dquot)) { |
1195 | *warntype = QUOTA_NL_IHARDWARN; |
1196 | return -EDQUOT; |
1197 | } |
1198 | |
1199 | if (dquot->dq_dqb.dqb_isoftlimit && |
1200 | newinodes > dquot->dq_dqb.dqb_isoftlimit && |
1201 | dquot->dq_dqb.dqb_itime && |
1202 | get_seconds() >= dquot->dq_dqb.dqb_itime && |
1203 | !ignore_hardlimit(dquot)) { |
1204 | *warntype = QUOTA_NL_ISOFTLONGWARN; |
1205 | return -EDQUOT; |
1206 | } |
1207 | |
1208 | if (dquot->dq_dqb.dqb_isoftlimit && |
1209 | newinodes > dquot->dq_dqb.dqb_isoftlimit && |
1210 | dquot->dq_dqb.dqb_itime == 0) { |
1211 | *warntype = QUOTA_NL_ISOFTWARN; |
1212 | dquot->dq_dqb.dqb_itime = get_seconds() + |
1213 | sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; |
1214 | } |
1215 | |
1216 | return 0; |
1217 | } |
1218 | |
1219 | /* needs dq_data_lock */ |
1220 | static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) |
1221 | { |
1222 | qsize_t tspace; |
1223 | struct super_block *sb = dquot->dq_sb; |
1224 | |
1225 | *warntype = QUOTA_NL_NOWARN; |
1226 | if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) || |
1227 | test_bit(DQ_FAKE_B, &dquot->dq_flags)) |
1228 | return 0; |
1229 | |
1230 | tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace |
1231 | + space; |
1232 | |
1233 | if (dquot->dq_dqb.dqb_bhardlimit && |
1234 | tspace > dquot->dq_dqb.dqb_bhardlimit && |
1235 | !ignore_hardlimit(dquot)) { |
1236 | if (!prealloc) |
1237 | *warntype = QUOTA_NL_BHARDWARN; |
1238 | return -EDQUOT; |
1239 | } |
1240 | |
1241 | if (dquot->dq_dqb.dqb_bsoftlimit && |
1242 | tspace > dquot->dq_dqb.dqb_bsoftlimit && |
1243 | dquot->dq_dqb.dqb_btime && |
1244 | get_seconds() >= dquot->dq_dqb.dqb_btime && |
1245 | !ignore_hardlimit(dquot)) { |
1246 | if (!prealloc) |
1247 | *warntype = QUOTA_NL_BSOFTLONGWARN; |
1248 | return -EDQUOT; |
1249 | } |
1250 | |
1251 | if (dquot->dq_dqb.dqb_bsoftlimit && |
1252 | tspace > dquot->dq_dqb.dqb_bsoftlimit && |
1253 | dquot->dq_dqb.dqb_btime == 0) { |
1254 | if (!prealloc) { |
1255 | *warntype = QUOTA_NL_BSOFTWARN; |
1256 | dquot->dq_dqb.dqb_btime = get_seconds() + |
1257 | sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace; |
1258 | } |
1259 | else |
1260 | /* |
1261 | * We don't allow preallocation to exceed softlimit so exceeding will |
1262 | * be always printed |
1263 | */ |
1264 | return -EDQUOT; |
1265 | } |
1266 | |
1267 | return 0; |
1268 | } |
1269 | |
1270 | static int info_idq_free(struct dquot *dquot, qsize_t inodes) |
1271 | { |
1272 | qsize_t newinodes; |
1273 | |
1274 | if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || |
1275 | dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || |
1276 | !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type)) |
1277 | return QUOTA_NL_NOWARN; |
1278 | |
1279 | newinodes = dquot->dq_dqb.dqb_curinodes - inodes; |
1280 | if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) |
1281 | return QUOTA_NL_ISOFTBELOW; |
1282 | if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && |
1283 | newinodes < dquot->dq_dqb.dqb_ihardlimit) |
1284 | return QUOTA_NL_IHARDBELOW; |
1285 | return QUOTA_NL_NOWARN; |
1286 | } |
1287 | |
1288 | static int info_bdq_free(struct dquot *dquot, qsize_t space) |
1289 | { |
1290 | if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || |
1291 | dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) |
1292 | return QUOTA_NL_NOWARN; |
1293 | |
1294 | if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) |
1295 | return QUOTA_NL_BSOFTBELOW; |
1296 | if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && |
1297 | dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) |
1298 | return QUOTA_NL_BHARDBELOW; |
1299 | return QUOTA_NL_NOWARN; |
1300 | } |
1301 | |
1302 | /* |
1303 | * Initialize quota pointers in inode |
1304 | * |
1305 | * We do things in a bit complicated way but by that we avoid calling |
1306 | * dqget() and thus filesystem callbacks under dqptr_sem. |
1307 | * |
1308 | * It is better to call this function outside of any transaction as it |
1309 | * might need a lot of space in journal for dquot structure allocation. |
1310 | */ |
1311 | static void __dquot_initialize(struct inode *inode, int type) |
1312 | { |
1313 | unsigned int id = 0; |
1314 | int cnt; |
1315 | struct dquot *got[MAXQUOTAS]; |
1316 | struct super_block *sb = inode->i_sb; |
1317 | qsize_t rsv; |
1318 | |
1319 | /* First test before acquiring mutex - solves deadlocks when we |
1320 | * re-enter the quota code and are already holding the mutex */ |
1321 | if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) |
1322 | return; |
1323 | |
1324 | /* First get references to structures we might need. */ |
1325 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1326 | got[cnt] = NULL; |
1327 | if (type != -1 && cnt != type) |
1328 | continue; |
1329 | switch (cnt) { |
1330 | case USRQUOTA: |
1331 | id = inode->i_uid; |
1332 | break; |
1333 | case GRPQUOTA: |
1334 | id = inode->i_gid; |
1335 | break; |
1336 | } |
1337 | got[cnt] = dqget(sb, id, cnt); |
1338 | } |
1339 | |
1340 | down_write(&sb_dqopt(sb)->dqptr_sem); |
1341 | if (IS_NOQUOTA(inode)) |
1342 | goto out_err; |
1343 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1344 | if (type != -1 && cnt != type) |
1345 | continue; |
1346 | /* Avoid races with quotaoff() */ |
1347 | if (!sb_has_quota_active(sb, cnt)) |
1348 | continue; |
1349 | if (!inode->i_dquot[cnt]) { |
1350 | inode->i_dquot[cnt] = got[cnt]; |
1351 | got[cnt] = NULL; |
1352 | /* |
1353 | * Make quota reservation system happy if someone |
1354 | * did a write before quota was turned on |
1355 | */ |
1356 | rsv = inode_get_rsv_space(inode); |
1357 | if (unlikely(rsv)) |
1358 | dquot_resv_space(inode->i_dquot[cnt], rsv); |
1359 | } |
1360 | } |
1361 | out_err: |
1362 | up_write(&sb_dqopt(sb)->dqptr_sem); |
1363 | /* Drop unused references */ |
1364 | dqput_all(got); |
1365 | } |
1366 | |
1367 | void dquot_initialize(struct inode *inode) |
1368 | { |
1369 | __dquot_initialize(inode, -1); |
1370 | } |
1371 | EXPORT_SYMBOL(dquot_initialize); |
1372 | |
1373 | /* |
1374 | * Release all quotas referenced by inode |
1375 | */ |
1376 | static void __dquot_drop(struct inode *inode) |
1377 | { |
1378 | int cnt; |
1379 | struct dquot *put[MAXQUOTAS]; |
1380 | |
1381 | down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1382 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1383 | put[cnt] = inode->i_dquot[cnt]; |
1384 | inode->i_dquot[cnt] = NULL; |
1385 | } |
1386 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1387 | dqput_all(put); |
1388 | } |
1389 | |
1390 | void dquot_drop(struct inode *inode) |
1391 | { |
1392 | int cnt; |
1393 | |
1394 | if (IS_NOQUOTA(inode)) |
1395 | return; |
1396 | |
1397 | /* |
1398 | * Test before calling to rule out calls from proc and such |
1399 | * where we are not allowed to block. Note that this is |
1400 | * actually reliable test even without the lock - the caller |
1401 | * must assure that nobody can come after the DQUOT_DROP and |
1402 | * add quota pointers back anyway. |
1403 | */ |
1404 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1405 | if (inode->i_dquot[cnt]) |
1406 | break; |
1407 | } |
1408 | |
1409 | if (cnt < MAXQUOTAS) |
1410 | __dquot_drop(inode); |
1411 | } |
1412 | EXPORT_SYMBOL(dquot_drop); |
1413 | |
1414 | /* |
1415 | * inode_reserved_space is managed internally by quota, and protected by |
1416 | * i_lock similar to i_blocks+i_bytes. |
1417 | */ |
1418 | static qsize_t *inode_reserved_space(struct inode * inode) |
1419 | { |
1420 | /* Filesystem must explicitly define it's own method in order to use |
1421 | * quota reservation interface */ |
1422 | BUG_ON(!inode->i_sb->dq_op->get_reserved_space); |
1423 | return inode->i_sb->dq_op->get_reserved_space(inode); |
1424 | } |
1425 | |
1426 | void inode_add_rsv_space(struct inode *inode, qsize_t number) |
1427 | { |
1428 | spin_lock(&inode->i_lock); |
1429 | *inode_reserved_space(inode) += number; |
1430 | spin_unlock(&inode->i_lock); |
1431 | } |
1432 | EXPORT_SYMBOL(inode_add_rsv_space); |
1433 | |
1434 | void inode_claim_rsv_space(struct inode *inode, qsize_t number) |
1435 | { |
1436 | spin_lock(&inode->i_lock); |
1437 | *inode_reserved_space(inode) -= number; |
1438 | __inode_add_bytes(inode, number); |
1439 | spin_unlock(&inode->i_lock); |
1440 | } |
1441 | EXPORT_SYMBOL(inode_claim_rsv_space); |
1442 | |
1443 | void inode_sub_rsv_space(struct inode *inode, qsize_t number) |
1444 | { |
1445 | spin_lock(&inode->i_lock); |
1446 | *inode_reserved_space(inode) -= number; |
1447 | spin_unlock(&inode->i_lock); |
1448 | } |
1449 | EXPORT_SYMBOL(inode_sub_rsv_space); |
1450 | |
1451 | static qsize_t inode_get_rsv_space(struct inode *inode) |
1452 | { |
1453 | qsize_t ret; |
1454 | |
1455 | if (!inode->i_sb->dq_op->get_reserved_space) |
1456 | return 0; |
1457 | spin_lock(&inode->i_lock); |
1458 | ret = *inode_reserved_space(inode); |
1459 | spin_unlock(&inode->i_lock); |
1460 | return ret; |
1461 | } |
1462 | |
1463 | static void inode_incr_space(struct inode *inode, qsize_t number, |
1464 | int reserve) |
1465 | { |
1466 | if (reserve) |
1467 | inode_add_rsv_space(inode, number); |
1468 | else |
1469 | inode_add_bytes(inode, number); |
1470 | } |
1471 | |
1472 | static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) |
1473 | { |
1474 | if (reserve) |
1475 | inode_sub_rsv_space(inode, number); |
1476 | else |
1477 | inode_sub_bytes(inode, number); |
1478 | } |
1479 | |
1480 | /* |
1481 | * This functions updates i_blocks+i_bytes fields and quota information |
1482 | * (together with appropriate checks). |
1483 | * |
1484 | * NOTE: We absolutely rely on the fact that caller dirties the inode |
1485 | * (usually helpers in quotaops.h care about this) and holds a handle for |
1486 | * the current transaction so that dquot write and inode write go into the |
1487 | * same transaction. |
1488 | */ |
1489 | |
1490 | /* |
1491 | * This operation can block, but only after everything is updated |
1492 | */ |
1493 | int __dquot_alloc_space(struct inode *inode, qsize_t number, |
1494 | int warn, int reserve) |
1495 | { |
1496 | int cnt, ret = 0; |
1497 | char warntype[MAXQUOTAS]; |
1498 | |
1499 | /* |
1500 | * First test before acquiring mutex - solves deadlocks when we |
1501 | * re-enter the quota code and are already holding the mutex |
1502 | */ |
1503 | if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { |
1504 | inode_incr_space(inode, number, reserve); |
1505 | goto out; |
1506 | } |
1507 | |
1508 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1509 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1510 | warntype[cnt] = QUOTA_NL_NOWARN; |
1511 | |
1512 | spin_lock(&dq_data_lock); |
1513 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1514 | if (!inode->i_dquot[cnt]) |
1515 | continue; |
1516 | ret = check_bdq(inode->i_dquot[cnt], number, !warn, |
1517 | warntype+cnt); |
1518 | if (ret) { |
1519 | spin_unlock(&dq_data_lock); |
1520 | goto out_flush_warn; |
1521 | } |
1522 | } |
1523 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1524 | if (!inode->i_dquot[cnt]) |
1525 | continue; |
1526 | if (reserve) |
1527 | dquot_resv_space(inode->i_dquot[cnt], number); |
1528 | else |
1529 | dquot_incr_space(inode->i_dquot[cnt], number); |
1530 | } |
1531 | inode_incr_space(inode, number, reserve); |
1532 | spin_unlock(&dq_data_lock); |
1533 | |
1534 | if (reserve) |
1535 | goto out_flush_warn; |
1536 | mark_all_dquot_dirty(inode->i_dquot); |
1537 | out_flush_warn: |
1538 | flush_warnings(inode->i_dquot, warntype); |
1539 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1540 | out: |
1541 | return ret; |
1542 | } |
1543 | EXPORT_SYMBOL(__dquot_alloc_space); |
1544 | |
1545 | /* |
1546 | * This operation can block, but only after everything is updated |
1547 | */ |
1548 | int dquot_alloc_inode(const struct inode *inode) |
1549 | { |
1550 | int cnt, ret = 0; |
1551 | char warntype[MAXQUOTAS]; |
1552 | |
1553 | /* First test before acquiring mutex - solves deadlocks when we |
1554 | * re-enter the quota code and are already holding the mutex */ |
1555 | if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) |
1556 | return 0; |
1557 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1558 | warntype[cnt] = QUOTA_NL_NOWARN; |
1559 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1560 | spin_lock(&dq_data_lock); |
1561 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1562 | if (!inode->i_dquot[cnt]) |
1563 | continue; |
1564 | ret = check_idq(inode->i_dquot[cnt], 1, warntype + cnt); |
1565 | if (ret) |
1566 | goto warn_put_all; |
1567 | } |
1568 | |
1569 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1570 | if (!inode->i_dquot[cnt]) |
1571 | continue; |
1572 | dquot_incr_inodes(inode->i_dquot[cnt], 1); |
1573 | } |
1574 | |
1575 | warn_put_all: |
1576 | spin_unlock(&dq_data_lock); |
1577 | if (ret == 0) |
1578 | mark_all_dquot_dirty(inode->i_dquot); |
1579 | flush_warnings(inode->i_dquot, warntype); |
1580 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1581 | return ret; |
1582 | } |
1583 | EXPORT_SYMBOL(dquot_alloc_inode); |
1584 | |
1585 | /* |
1586 | * Convert in-memory reserved quotas to real consumed quotas |
1587 | */ |
1588 | int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) |
1589 | { |
1590 | int cnt; |
1591 | |
1592 | if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { |
1593 | inode_claim_rsv_space(inode, number); |
1594 | return 0; |
1595 | } |
1596 | |
1597 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1598 | spin_lock(&dq_data_lock); |
1599 | /* Claim reserved quotas to allocated quotas */ |
1600 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1601 | if (inode->i_dquot[cnt]) |
1602 | dquot_claim_reserved_space(inode->i_dquot[cnt], |
1603 | number); |
1604 | } |
1605 | /* Update inode bytes */ |
1606 | inode_claim_rsv_space(inode, number); |
1607 | spin_unlock(&dq_data_lock); |
1608 | mark_all_dquot_dirty(inode->i_dquot); |
1609 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1610 | return 0; |
1611 | } |
1612 | EXPORT_SYMBOL(dquot_claim_space_nodirty); |
1613 | |
1614 | /* |
1615 | * This operation can block, but only after everything is updated |
1616 | */ |
1617 | void __dquot_free_space(struct inode *inode, qsize_t number, int reserve) |
1618 | { |
1619 | unsigned int cnt; |
1620 | char warntype[MAXQUOTAS]; |
1621 | |
1622 | /* First test before acquiring mutex - solves deadlocks when we |
1623 | * re-enter the quota code and are already holding the mutex */ |
1624 | if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { |
1625 | inode_decr_space(inode, number, reserve); |
1626 | return; |
1627 | } |
1628 | |
1629 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1630 | spin_lock(&dq_data_lock); |
1631 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1632 | if (!inode->i_dquot[cnt]) |
1633 | continue; |
1634 | warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number); |
1635 | if (reserve) |
1636 | dquot_free_reserved_space(inode->i_dquot[cnt], number); |
1637 | else |
1638 | dquot_decr_space(inode->i_dquot[cnt], number); |
1639 | } |
1640 | inode_decr_space(inode, number, reserve); |
1641 | spin_unlock(&dq_data_lock); |
1642 | |
1643 | if (reserve) |
1644 | goto out_unlock; |
1645 | mark_all_dquot_dirty(inode->i_dquot); |
1646 | out_unlock: |
1647 | flush_warnings(inode->i_dquot, warntype); |
1648 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1649 | } |
1650 | EXPORT_SYMBOL(__dquot_free_space); |
1651 | |
1652 | /* |
1653 | * This operation can block, but only after everything is updated |
1654 | */ |
1655 | void dquot_free_inode(const struct inode *inode) |
1656 | { |
1657 | unsigned int cnt; |
1658 | char warntype[MAXQUOTAS]; |
1659 | |
1660 | /* First test before acquiring mutex - solves deadlocks when we |
1661 | * re-enter the quota code and are already holding the mutex */ |
1662 | if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) |
1663 | return; |
1664 | |
1665 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1666 | spin_lock(&dq_data_lock); |
1667 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1668 | if (!inode->i_dquot[cnt]) |
1669 | continue; |
1670 | warntype[cnt] = info_idq_free(inode->i_dquot[cnt], 1); |
1671 | dquot_decr_inodes(inode->i_dquot[cnt], 1); |
1672 | } |
1673 | spin_unlock(&dq_data_lock); |
1674 | mark_all_dquot_dirty(inode->i_dquot); |
1675 | flush_warnings(inode->i_dquot, warntype); |
1676 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1677 | } |
1678 | EXPORT_SYMBOL(dquot_free_inode); |
1679 | |
1680 | /* |
1681 | * Transfer the number of inode and blocks from one diskquota to an other. |
1682 | * |
1683 | * This operation can block, but only after everything is updated |
1684 | * A transaction must be started when entering this function. |
1685 | */ |
1686 | static int __dquot_transfer(struct inode *inode, qid_t *chid, unsigned long mask) |
1687 | { |
1688 | qsize_t space, cur_space; |
1689 | qsize_t rsv_space = 0; |
1690 | struct dquot *transfer_from[MAXQUOTAS]; |
1691 | struct dquot *transfer_to[MAXQUOTAS]; |
1692 | int cnt, ret = 0; |
1693 | char warntype_to[MAXQUOTAS]; |
1694 | char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS]; |
1695 | |
1696 | /* First test before acquiring mutex - solves deadlocks when we |
1697 | * re-enter the quota code and are already holding the mutex */ |
1698 | if (IS_NOQUOTA(inode)) |
1699 | return 0; |
1700 | /* Initialize the arrays */ |
1701 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1702 | transfer_from[cnt] = NULL; |
1703 | transfer_to[cnt] = NULL; |
1704 | warntype_to[cnt] = QUOTA_NL_NOWARN; |
1705 | } |
1706 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1707 | if (mask & (1 << cnt)) |
1708 | transfer_to[cnt] = dqget(inode->i_sb, chid[cnt], cnt); |
1709 | } |
1710 | down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1711 | if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ |
1712 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1713 | goto put_all; |
1714 | } |
1715 | spin_lock(&dq_data_lock); |
1716 | cur_space = inode_get_bytes(inode); |
1717 | rsv_space = inode_get_rsv_space(inode); |
1718 | space = cur_space + rsv_space; |
1719 | /* Build the transfer_from list and check the limits */ |
1720 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1721 | if (!transfer_to[cnt]) |
1722 | continue; |
1723 | transfer_from[cnt] = inode->i_dquot[cnt]; |
1724 | ret = check_idq(transfer_to[cnt], 1, warntype_to + cnt); |
1725 | if (ret) |
1726 | goto over_quota; |
1727 | ret = check_bdq(transfer_to[cnt], space, 0, warntype_to + cnt); |
1728 | if (ret) |
1729 | goto over_quota; |
1730 | } |
1731 | |
1732 | /* |
1733 | * Finally perform the needed transfer from transfer_from to transfer_to |
1734 | */ |
1735 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1736 | /* |
1737 | * Skip changes for same uid or gid or for turned off quota-type. |
1738 | */ |
1739 | if (!transfer_to[cnt]) |
1740 | continue; |
1741 | |
1742 | /* Due to IO error we might not have transfer_from[] structure */ |
1743 | if (transfer_from[cnt]) { |
1744 | warntype_from_inodes[cnt] = |
1745 | info_idq_free(transfer_from[cnt], 1); |
1746 | warntype_from_space[cnt] = |
1747 | info_bdq_free(transfer_from[cnt], space); |
1748 | dquot_decr_inodes(transfer_from[cnt], 1); |
1749 | dquot_decr_space(transfer_from[cnt], cur_space); |
1750 | dquot_free_reserved_space(transfer_from[cnt], |
1751 | rsv_space); |
1752 | } |
1753 | |
1754 | dquot_incr_inodes(transfer_to[cnt], 1); |
1755 | dquot_incr_space(transfer_to[cnt], cur_space); |
1756 | dquot_resv_space(transfer_to[cnt], rsv_space); |
1757 | |
1758 | inode->i_dquot[cnt] = transfer_to[cnt]; |
1759 | } |
1760 | spin_unlock(&dq_data_lock); |
1761 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1762 | |
1763 | mark_all_dquot_dirty(transfer_from); |
1764 | mark_all_dquot_dirty(transfer_to); |
1765 | /* The reference we got is transferred to the inode */ |
1766 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1767 | transfer_to[cnt] = NULL; |
1768 | warn_put_all: |
1769 | flush_warnings(transfer_to, warntype_to); |
1770 | flush_warnings(transfer_from, warntype_from_inodes); |
1771 | flush_warnings(transfer_from, warntype_from_space); |
1772 | put_all: |
1773 | dqput_all(transfer_from); |
1774 | dqput_all(transfer_to); |
1775 | return ret; |
1776 | over_quota: |
1777 | spin_unlock(&dq_data_lock); |
1778 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); |
1779 | /* Clear dquot pointers we don't want to dqput() */ |
1780 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1781 | transfer_from[cnt] = NULL; |
1782 | goto warn_put_all; |
1783 | } |
1784 | |
1785 | /* Wrapper for transferring ownership of an inode for uid/gid only |
1786 | * Called from FSXXX_setattr() |
1787 | */ |
1788 | int dquot_transfer(struct inode *inode, struct iattr *iattr) |
1789 | { |
1790 | qid_t chid[MAXQUOTAS]; |
1791 | unsigned long mask = 0; |
1792 | |
1793 | if (iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) { |
1794 | mask |= 1 << USRQUOTA; |
1795 | chid[USRQUOTA] = iattr->ia_uid; |
1796 | } |
1797 | if (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid) { |
1798 | mask |= 1 << GRPQUOTA; |
1799 | chid[GRPQUOTA] = iattr->ia_gid; |
1800 | } |
1801 | if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) { |
1802 | dquot_initialize(inode); |
1803 | return __dquot_transfer(inode, chid, mask); |
1804 | } |
1805 | return 0; |
1806 | } |
1807 | EXPORT_SYMBOL(dquot_transfer); |
1808 | |
1809 | /* |
1810 | * Write info of quota file to disk |
1811 | */ |
1812 | int dquot_commit_info(struct super_block *sb, int type) |
1813 | { |
1814 | int ret; |
1815 | struct quota_info *dqopt = sb_dqopt(sb); |
1816 | |
1817 | mutex_lock(&dqopt->dqio_mutex); |
1818 | ret = dqopt->ops[type]->write_file_info(sb, type); |
1819 | mutex_unlock(&dqopt->dqio_mutex); |
1820 | return ret; |
1821 | } |
1822 | EXPORT_SYMBOL(dquot_commit_info); |
1823 | |
1824 | /* |
1825 | * Definitions of diskquota operations. |
1826 | */ |
1827 | const struct dquot_operations dquot_operations = { |
1828 | .write_dquot = dquot_commit, |
1829 | .acquire_dquot = dquot_acquire, |
1830 | .release_dquot = dquot_release, |
1831 | .mark_dirty = dquot_mark_dquot_dirty, |
1832 | .write_info = dquot_commit_info, |
1833 | .alloc_dquot = dquot_alloc, |
1834 | .destroy_dquot = dquot_destroy, |
1835 | }; |
1836 | |
1837 | /* |
1838 | * Generic helper for ->open on filesystems supporting disk quotas. |
1839 | */ |
1840 | int dquot_file_open(struct inode *inode, struct file *file) |
1841 | { |
1842 | int error; |
1843 | |
1844 | error = generic_file_open(inode, file); |
1845 | if (!error && (file->f_mode & FMODE_WRITE)) |
1846 | dquot_initialize(inode); |
1847 | return error; |
1848 | } |
1849 | EXPORT_SYMBOL(dquot_file_open); |
1850 | |
1851 | /* |
1852 | * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) |
1853 | */ |
1854 | int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags) |
1855 | { |
1856 | int cnt, ret = 0; |
1857 | struct quota_info *dqopt = sb_dqopt(sb); |
1858 | struct inode *toputinode[MAXQUOTAS]; |
1859 | |
1860 | /* Cannot turn off usage accounting without turning off limits, or |
1861 | * suspend quotas and simultaneously turn quotas off. */ |
1862 | if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) |
1863 | || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | |
1864 | DQUOT_USAGE_ENABLED))) |
1865 | return -EINVAL; |
1866 | |
1867 | /* We need to serialize quota_off() for device */ |
1868 | mutex_lock(&dqopt->dqonoff_mutex); |
1869 | |
1870 | /* |
1871 | * Skip everything if there's nothing to do. We have to do this because |
1872 | * sometimes we are called when fill_super() failed and calling |
1873 | * sync_fs() in such cases does no good. |
1874 | */ |
1875 | if (!sb_any_quota_loaded(sb)) { |
1876 | mutex_unlock(&dqopt->dqonoff_mutex); |
1877 | return 0; |
1878 | } |
1879 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1880 | toputinode[cnt] = NULL; |
1881 | if (type != -1 && cnt != type) |
1882 | continue; |
1883 | if (!sb_has_quota_loaded(sb, cnt)) |
1884 | continue; |
1885 | |
1886 | if (flags & DQUOT_SUSPENDED) { |
1887 | spin_lock(&dq_state_lock); |
1888 | dqopt->flags |= |
1889 | dquot_state_flag(DQUOT_SUSPENDED, cnt); |
1890 | spin_unlock(&dq_state_lock); |
1891 | } else { |
1892 | spin_lock(&dq_state_lock); |
1893 | dqopt->flags &= ~dquot_state_flag(flags, cnt); |
1894 | /* Turning off suspended quotas? */ |
1895 | if (!sb_has_quota_loaded(sb, cnt) && |
1896 | sb_has_quota_suspended(sb, cnt)) { |
1897 | dqopt->flags &= ~dquot_state_flag( |
1898 | DQUOT_SUSPENDED, cnt); |
1899 | spin_unlock(&dq_state_lock); |
1900 | iput(dqopt->files[cnt]); |
1901 | dqopt->files[cnt] = NULL; |
1902 | continue; |
1903 | } |
1904 | spin_unlock(&dq_state_lock); |
1905 | } |
1906 | |
1907 | /* We still have to keep quota loaded? */ |
1908 | if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) |
1909 | continue; |
1910 | |
1911 | /* Note: these are blocking operations */ |
1912 | drop_dquot_ref(sb, cnt); |
1913 | invalidate_dquots(sb, cnt); |
1914 | /* |
1915 | * Now all dquots should be invalidated, all writes done so we |
1916 | * should be only users of the info. No locks needed. |
1917 | */ |
1918 | if (info_dirty(&dqopt->info[cnt])) |
1919 | sb->dq_op->write_info(sb, cnt); |
1920 | if (dqopt->ops[cnt]->free_file_info) |
1921 | dqopt->ops[cnt]->free_file_info(sb, cnt); |
1922 | put_quota_format(dqopt->info[cnt].dqi_format); |
1923 | |
1924 | toputinode[cnt] = dqopt->files[cnt]; |
1925 | if (!sb_has_quota_loaded(sb, cnt)) |
1926 | dqopt->files[cnt] = NULL; |
1927 | dqopt->info[cnt].dqi_flags = 0; |
1928 | dqopt->info[cnt].dqi_igrace = 0; |
1929 | dqopt->info[cnt].dqi_bgrace = 0; |
1930 | dqopt->ops[cnt] = NULL; |
1931 | } |
1932 | mutex_unlock(&dqopt->dqonoff_mutex); |
1933 | |
1934 | /* Skip syncing and setting flags if quota files are hidden */ |
1935 | if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) |
1936 | goto put_inodes; |
1937 | |
1938 | /* Sync the superblock so that buffers with quota data are written to |
1939 | * disk (and so userspace sees correct data afterwards). */ |
1940 | if (sb->s_op->sync_fs) |
1941 | sb->s_op->sync_fs(sb, 1); |
1942 | sync_blockdev(sb->s_bdev); |
1943 | /* Now the quota files are just ordinary files and we can set the |
1944 | * inode flags back. Moreover we discard the pagecache so that |
1945 | * userspace sees the writes we did bypassing the pagecache. We |
1946 | * must also discard the blockdev buffers so that we see the |
1947 | * changes done by userspace on the next quotaon() */ |
1948 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1949 | if (toputinode[cnt]) { |
1950 | mutex_lock(&dqopt->dqonoff_mutex); |
1951 | /* If quota was reenabled in the meantime, we have |
1952 | * nothing to do */ |
1953 | if (!sb_has_quota_loaded(sb, cnt)) { |
1954 | mutex_lock_nested(&toputinode[cnt]->i_mutex, |
1955 | I_MUTEX_QUOTA); |
1956 | toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | |
1957 | S_NOATIME | S_NOQUOTA); |
1958 | truncate_inode_pages(&toputinode[cnt]->i_data, |
1959 | 0); |
1960 | mutex_unlock(&toputinode[cnt]->i_mutex); |
1961 | mark_inode_dirty(toputinode[cnt]); |
1962 | } |
1963 | mutex_unlock(&dqopt->dqonoff_mutex); |
1964 | } |
1965 | if (sb->s_bdev) |
1966 | invalidate_bdev(sb->s_bdev); |
1967 | put_inodes: |
1968 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) |
1969 | if (toputinode[cnt]) { |
1970 | /* On remount RO, we keep the inode pointer so that we |
1971 | * can reenable quota on the subsequent remount RW. We |
1972 | * have to check 'flags' variable and not use sb_has_ |
1973 | * function because another quotaon / quotaoff could |
1974 | * change global state before we got here. We refuse |
1975 | * to suspend quotas when there is pending delete on |
1976 | * the quota file... */ |
1977 | if (!(flags & DQUOT_SUSPENDED)) |
1978 | iput(toputinode[cnt]); |
1979 | else if (!toputinode[cnt]->i_nlink) |
1980 | ret = -EBUSY; |
1981 | } |
1982 | return ret; |
1983 | } |
1984 | EXPORT_SYMBOL(vfs_quota_disable); |
1985 | |
1986 | int vfs_quota_off(struct super_block *sb, int type, int remount) |
1987 | { |
1988 | return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED : |
1989 | (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED)); |
1990 | } |
1991 | EXPORT_SYMBOL(vfs_quota_off); |
1992 | /* |
1993 | * Turn quotas on on a device |
1994 | */ |
1995 | |
1996 | /* |
1997 | * Helper function to turn quotas on when we already have the inode of |
1998 | * quota file and no quota information is loaded. |
1999 | */ |
2000 | static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, |
2001 | unsigned int flags) |
2002 | { |
2003 | struct quota_format_type *fmt = find_quota_format(format_id); |
2004 | struct super_block *sb = inode->i_sb; |
2005 | struct quota_info *dqopt = sb_dqopt(sb); |
2006 | int error; |
2007 | int oldflags = -1; |
2008 | |
2009 | if (!fmt) |
2010 | return -ESRCH; |
2011 | if (!S_ISREG(inode->i_mode)) { |
2012 | error = -EACCES; |
2013 | goto out_fmt; |
2014 | } |
2015 | if (IS_RDONLY(inode)) { |
2016 | error = -EROFS; |
2017 | goto out_fmt; |
2018 | } |
2019 | if (!sb->s_op->quota_write || !sb->s_op->quota_read) { |
2020 | error = -EINVAL; |
2021 | goto out_fmt; |
2022 | } |
2023 | /* Usage always has to be set... */ |
2024 | if (!(flags & DQUOT_USAGE_ENABLED)) { |
2025 | error = -EINVAL; |
2026 | goto out_fmt; |
2027 | } |
2028 | |
2029 | if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { |
2030 | /* As we bypass the pagecache we must now flush all the |
2031 | * dirty data and invalidate caches so that kernel sees |
2032 | * changes from userspace. It is not enough to just flush |
2033 | * the quota file since if blocksize < pagesize, invalidation |
2034 | * of the cache could fail because of other unrelated dirty |
2035 | * data */ |
2036 | sync_filesystem(sb); |
2037 | invalidate_bdev(sb->s_bdev); |
2038 | } |
2039 | mutex_lock(&dqopt->dqonoff_mutex); |
2040 | if (sb_has_quota_loaded(sb, type)) { |
2041 | error = -EBUSY; |
2042 | goto out_lock; |
2043 | } |
2044 | |
2045 | if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { |
2046 | /* We don't want quota and atime on quota files (deadlocks |
2047 | * possible) Also nobody should write to the file - we use |
2048 | * special IO operations which ignore the immutable bit. */ |
2049 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); |
2050 | oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | |
2051 | S_NOQUOTA); |
2052 | inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; |
2053 | mutex_unlock(&inode->i_mutex); |
2054 | /* |
2055 | * When S_NOQUOTA is set, remove dquot references as no more |
2056 | * references can be added |
2057 | */ |
2058 | __dquot_drop(inode); |
2059 | } |
2060 | |
2061 | error = -EIO; |
2062 | dqopt->files[type] = igrab(inode); |
2063 | if (!dqopt->files[type]) |
2064 | goto out_lock; |
2065 | error = -EINVAL; |
2066 | if (!fmt->qf_ops->check_quota_file(sb, type)) |
2067 | goto out_file_init; |
2068 | |
2069 | dqopt->ops[type] = fmt->qf_ops; |
2070 | dqopt->info[type].dqi_format = fmt; |
2071 | dqopt->info[type].dqi_fmt_id = format_id; |
2072 | INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); |
2073 | mutex_lock(&dqopt->dqio_mutex); |
2074 | error = dqopt->ops[type]->read_file_info(sb, type); |
2075 | if (error < 0) { |
2076 | mutex_unlock(&dqopt->dqio_mutex); |
2077 | goto out_file_init; |
2078 | } |
2079 | mutex_unlock(&dqopt->dqio_mutex); |
2080 | spin_lock(&dq_state_lock); |
2081 | dqopt->flags |= dquot_state_flag(flags, type); |
2082 | spin_unlock(&dq_state_lock); |
2083 | |
2084 | add_dquot_ref(sb, type); |
2085 | mutex_unlock(&dqopt->dqonoff_mutex); |
2086 | |
2087 | return 0; |
2088 | |
2089 | out_file_init: |
2090 | dqopt->files[type] = NULL; |
2091 | iput(inode); |
2092 | out_lock: |
2093 | if (oldflags != -1) { |
2094 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); |
2095 | /* Set the flags back (in the case of accidental quotaon() |
2096 | * on a wrong file we don't want to mess up the flags) */ |
2097 | inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); |
2098 | inode->i_flags |= oldflags; |
2099 | mutex_unlock(&inode->i_mutex); |
2100 | } |
2101 | mutex_unlock(&dqopt->dqonoff_mutex); |
2102 | out_fmt: |
2103 | put_quota_format(fmt); |
2104 | |
2105 | return error; |
2106 | } |
2107 | |
2108 | /* Reenable quotas on remount RW */ |
2109 | static int vfs_quota_on_remount(struct super_block *sb, int type) |
2110 | { |
2111 | struct quota_info *dqopt = sb_dqopt(sb); |
2112 | struct inode *inode; |
2113 | int ret; |
2114 | unsigned int flags; |
2115 | |
2116 | mutex_lock(&dqopt->dqonoff_mutex); |
2117 | if (!sb_has_quota_suspended(sb, type)) { |
2118 | mutex_unlock(&dqopt->dqonoff_mutex); |
2119 | return 0; |
2120 | } |
2121 | inode = dqopt->files[type]; |
2122 | dqopt->files[type] = NULL; |
2123 | spin_lock(&dq_state_lock); |
2124 | flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | |
2125 | DQUOT_LIMITS_ENABLED, type); |
2126 | dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type); |
2127 | spin_unlock(&dq_state_lock); |
2128 | mutex_unlock(&dqopt->dqonoff_mutex); |
2129 | |
2130 | flags = dquot_generic_flag(flags, type); |
2131 | ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id, |
2132 | flags); |
2133 | iput(inode); |
2134 | |
2135 | return ret; |
2136 | } |
2137 | |
2138 | int vfs_quota_on_path(struct super_block *sb, int type, int format_id, |
2139 | struct path *path) |
2140 | { |
2141 | int error = security_quota_on(path->dentry); |
2142 | if (error) |
2143 | return error; |
2144 | /* Quota file not on the same filesystem? */ |
2145 | if (path->mnt->mnt_sb != sb) |
2146 | error = -EXDEV; |
2147 | else |
2148 | error = vfs_load_quota_inode(path->dentry->d_inode, type, |
2149 | format_id, DQUOT_USAGE_ENABLED | |
2150 | DQUOT_LIMITS_ENABLED); |
2151 | return error; |
2152 | } |
2153 | EXPORT_SYMBOL(vfs_quota_on_path); |
2154 | |
2155 | int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name, |
2156 | int remount) |
2157 | { |
2158 | struct path path; |
2159 | int error; |
2160 | |
2161 | if (remount) |
2162 | return vfs_quota_on_remount(sb, type); |
2163 | |
2164 | error = kern_path(name, LOOKUP_FOLLOW, &path); |
2165 | if (!error) { |
2166 | error = vfs_quota_on_path(sb, type, format_id, &path); |
2167 | path_put(&path); |
2168 | } |
2169 | return error; |
2170 | } |
2171 | EXPORT_SYMBOL(vfs_quota_on); |
2172 | |
2173 | /* |
2174 | * More powerful function for turning on quotas allowing setting |
2175 | * of individual quota flags |
2176 | */ |
2177 | int vfs_quota_enable(struct inode *inode, int type, int format_id, |
2178 | unsigned int flags) |
2179 | { |
2180 | int ret = 0; |
2181 | struct super_block *sb = inode->i_sb; |
2182 | struct quota_info *dqopt = sb_dqopt(sb); |
2183 | |
2184 | /* Just unsuspend quotas? */ |
2185 | if (flags & DQUOT_SUSPENDED) |
2186 | return vfs_quota_on_remount(sb, type); |
2187 | if (!flags) |
2188 | return 0; |
2189 | /* Just updating flags needed? */ |
2190 | if (sb_has_quota_loaded(sb, type)) { |
2191 | mutex_lock(&dqopt->dqonoff_mutex); |
2192 | /* Now do a reliable test... */ |
2193 | if (!sb_has_quota_loaded(sb, type)) { |
2194 | mutex_unlock(&dqopt->dqonoff_mutex); |
2195 | goto load_quota; |
2196 | } |
2197 | if (flags & DQUOT_USAGE_ENABLED && |
2198 | sb_has_quota_usage_enabled(sb, type)) { |
2199 | ret = -EBUSY; |
2200 | goto out_lock; |
2201 | } |
2202 | if (flags & DQUOT_LIMITS_ENABLED && |
2203 | sb_has_quota_limits_enabled(sb, type)) { |
2204 | ret = -EBUSY; |
2205 | goto out_lock; |
2206 | } |
2207 | spin_lock(&dq_state_lock); |
2208 | sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); |
2209 | spin_unlock(&dq_state_lock); |
2210 | out_lock: |
2211 | mutex_unlock(&dqopt->dqonoff_mutex); |
2212 | return ret; |
2213 | } |
2214 | |
2215 | load_quota: |
2216 | return vfs_load_quota_inode(inode, type, format_id, flags); |
2217 | } |
2218 | EXPORT_SYMBOL(vfs_quota_enable); |
2219 | |
2220 | /* |
2221 | * This function is used when filesystem needs to initialize quotas |
2222 | * during mount time. |
2223 | */ |
2224 | int vfs_quota_on_mount(struct super_block *sb, char *qf_name, |
2225 | int format_id, int type) |
2226 | { |
2227 | struct dentry *dentry; |
2228 | int error; |
2229 | |
2230 | mutex_lock(&sb->s_root->d_inode->i_mutex); |
2231 | dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); |
2232 | mutex_unlock(&sb->s_root->d_inode->i_mutex); |
2233 | if (IS_ERR(dentry)) |
2234 | return PTR_ERR(dentry); |
2235 | |
2236 | if (!dentry->d_inode) { |
2237 | error = -ENOENT; |
2238 | goto out; |
2239 | } |
2240 | |
2241 | error = security_quota_on(dentry); |
2242 | if (!error) |
2243 | error = vfs_load_quota_inode(dentry->d_inode, type, format_id, |
2244 | DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); |
2245 | |
2246 | out: |
2247 | dput(dentry); |
2248 | return error; |
2249 | } |
2250 | EXPORT_SYMBOL(vfs_quota_on_mount); |
2251 | |
2252 | /* Wrapper to turn on quotas when remounting rw */ |
2253 | int vfs_dq_quota_on_remount(struct super_block *sb) |
2254 | { |
2255 | int cnt; |
2256 | int ret = 0, err; |
2257 | |
2258 | if (!sb->s_qcop || !sb->s_qcop->quota_on) |
2259 | return -ENOSYS; |
2260 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
2261 | err = sb->s_qcop->quota_on(sb, cnt, 0, NULL, 1); |
2262 | if (err < 0 && !ret) |
2263 | ret = err; |
2264 | } |
2265 | return ret; |
2266 | } |
2267 | EXPORT_SYMBOL(vfs_dq_quota_on_remount); |
2268 | |
2269 | static inline qsize_t qbtos(qsize_t blocks) |
2270 | { |
2271 | return blocks << QIF_DQBLKSIZE_BITS; |
2272 | } |
2273 | |
2274 | static inline qsize_t stoqb(qsize_t space) |
2275 | { |
2276 | return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; |
2277 | } |
2278 | |
2279 | /* Generic routine for getting common part of quota structure */ |
2280 | static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di) |
2281 | { |
2282 | struct mem_dqblk *dm = &dquot->dq_dqb; |
2283 | |
2284 | spin_lock(&dq_data_lock); |
2285 | di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit); |
2286 | di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit); |
2287 | di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace; |
2288 | di->dqb_ihardlimit = dm->dqb_ihardlimit; |
2289 | di->dqb_isoftlimit = dm->dqb_isoftlimit; |
2290 | di->dqb_curinodes = dm->dqb_curinodes; |
2291 | di->dqb_btime = dm->dqb_btime; |
2292 | di->dqb_itime = dm->dqb_itime; |
2293 | di->dqb_valid = QIF_ALL; |
2294 | spin_unlock(&dq_data_lock); |
2295 | } |
2296 | |
2297 | int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, |
2298 | struct if_dqblk *di) |
2299 | { |
2300 | struct dquot *dquot; |
2301 | |
2302 | dquot = dqget(sb, id, type); |
2303 | if (!dquot) |
2304 | return -ESRCH; |
2305 | do_get_dqblk(dquot, di); |
2306 | dqput(dquot); |
2307 | |
2308 | return 0; |
2309 | } |
2310 | EXPORT_SYMBOL(vfs_get_dqblk); |
2311 | |
2312 | /* Generic routine for setting common part of quota structure */ |
2313 | static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di) |
2314 | { |
2315 | struct mem_dqblk *dm = &dquot->dq_dqb; |
2316 | int check_blim = 0, check_ilim = 0; |
2317 | struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; |
2318 | |
2319 | if ((di->dqb_valid & QIF_BLIMITS && |
2320 | (di->dqb_bhardlimit > dqi->dqi_maxblimit || |
2321 | di->dqb_bsoftlimit > dqi->dqi_maxblimit)) || |
2322 | (di->dqb_valid & QIF_ILIMITS && |
2323 | (di->dqb_ihardlimit > dqi->dqi_maxilimit || |
2324 | di->dqb_isoftlimit > dqi->dqi_maxilimit))) |
2325 | return -ERANGE; |
2326 | |
2327 | spin_lock(&dq_data_lock); |
2328 | if (di->dqb_valid & QIF_SPACE) { |
2329 | dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace; |
2330 | check_blim = 1; |
2331 | set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); |
2332 | } |
2333 | if (di->dqb_valid & QIF_BLIMITS) { |
2334 | dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit); |
2335 | dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit); |
2336 | check_blim = 1; |
2337 | set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); |
2338 | } |
2339 | if (di->dqb_valid & QIF_INODES) { |
2340 | dm->dqb_curinodes = di->dqb_curinodes; |
2341 | check_ilim = 1; |
2342 | set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); |
2343 | } |
2344 | if (di->dqb_valid & QIF_ILIMITS) { |
2345 | dm->dqb_isoftlimit = di->dqb_isoftlimit; |
2346 | dm->dqb_ihardlimit = di->dqb_ihardlimit; |
2347 | check_ilim = 1; |
2348 | set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); |
2349 | } |
2350 | if (di->dqb_valid & QIF_BTIME) { |
2351 | dm->dqb_btime = di->dqb_btime; |
2352 | check_blim = 1; |
2353 | set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); |
2354 | } |
2355 | if (di->dqb_valid & QIF_ITIME) { |
2356 | dm->dqb_itime = di->dqb_itime; |
2357 | check_ilim = 1; |
2358 | set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); |
2359 | } |
2360 | |
2361 | if (check_blim) { |
2362 | if (!dm->dqb_bsoftlimit || |
2363 | dm->dqb_curspace < dm->dqb_bsoftlimit) { |
2364 | dm->dqb_btime = 0; |
2365 | clear_bit(DQ_BLKS_B, &dquot->dq_flags); |
2366 | } else if (!(di->dqb_valid & QIF_BTIME)) |
2367 | /* Set grace only if user hasn't provided his own... */ |
2368 | dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; |
2369 | } |
2370 | if (check_ilim) { |
2371 | if (!dm->dqb_isoftlimit || |
2372 | dm->dqb_curinodes < dm->dqb_isoftlimit) { |
2373 | dm->dqb_itime = 0; |
2374 | clear_bit(DQ_INODES_B, &dquot->dq_flags); |
2375 | } else if (!(di->dqb_valid & QIF_ITIME)) |
2376 | /* Set grace only if user hasn't provided his own... */ |
2377 | dm->dqb_itime = get_seconds() + dqi->dqi_igrace; |
2378 | } |
2379 | if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || |
2380 | dm->dqb_isoftlimit) |
2381 | clear_bit(DQ_FAKE_B, &dquot->dq_flags); |
2382 | else |
2383 | set_bit(DQ_FAKE_B, &dquot->dq_flags); |
2384 | spin_unlock(&dq_data_lock); |
2385 | mark_dquot_dirty(dquot); |
2386 | |
2387 | return 0; |
2388 | } |
2389 | |
2390 | int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, |
2391 | struct if_dqblk *di) |
2392 | { |
2393 | struct dquot *dquot; |
2394 | int rc; |
2395 | |
2396 | dquot = dqget(sb, id, type); |
2397 | if (!dquot) { |
2398 | rc = -ESRCH; |
2399 | goto out; |
2400 | } |
2401 | rc = do_set_dqblk(dquot, di); |
2402 | dqput(dquot); |
2403 | out: |
2404 | return rc; |
2405 | } |
2406 | EXPORT_SYMBOL(vfs_set_dqblk); |
2407 | |
2408 | /* Generic routine for getting common part of quota file information */ |
2409 | int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) |
2410 | { |
2411 | struct mem_dqinfo *mi; |
2412 | |
2413 | mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); |
2414 | if (!sb_has_quota_active(sb, type)) { |
2415 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
2416 | return -ESRCH; |
2417 | } |
2418 | mi = sb_dqopt(sb)->info + type; |
2419 | spin_lock(&dq_data_lock); |
2420 | ii->dqi_bgrace = mi->dqi_bgrace; |
2421 | ii->dqi_igrace = mi->dqi_igrace; |
2422 | ii->dqi_flags = mi->dqi_flags & DQF_MASK; |
2423 | ii->dqi_valid = IIF_ALL; |
2424 | spin_unlock(&dq_data_lock); |
2425 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
2426 | return 0; |
2427 | } |
2428 | EXPORT_SYMBOL(vfs_get_dqinfo); |
2429 | |
2430 | /* Generic routine for setting common part of quota file information */ |
2431 | int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) |
2432 | { |
2433 | struct mem_dqinfo *mi; |
2434 | int err = 0; |
2435 | |
2436 | mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); |
2437 | if (!sb_has_quota_active(sb, type)) { |
2438 | err = -ESRCH; |
2439 | goto out; |
2440 | } |
2441 | mi = sb_dqopt(sb)->info + type; |
2442 | spin_lock(&dq_data_lock); |
2443 | if (ii->dqi_valid & IIF_BGRACE) |
2444 | mi->dqi_bgrace = ii->dqi_bgrace; |
2445 | if (ii->dqi_valid & IIF_IGRACE) |
2446 | mi->dqi_igrace = ii->dqi_igrace; |
2447 | if (ii->dqi_valid & IIF_FLAGS) |
2448 | mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | |
2449 | (ii->dqi_flags & DQF_MASK); |
2450 | spin_unlock(&dq_data_lock); |
2451 | mark_info_dirty(sb, type); |
2452 | /* Force write to disk */ |
2453 | sb->dq_op->write_info(sb, type); |
2454 | out: |
2455 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
2456 | return err; |
2457 | } |
2458 | EXPORT_SYMBOL(vfs_set_dqinfo); |
2459 | |
2460 | const struct quotactl_ops vfs_quotactl_ops = { |
2461 | .quota_on = vfs_quota_on, |
2462 | .quota_off = vfs_quota_off, |
2463 | .quota_sync = vfs_quota_sync, |
2464 | .get_info = vfs_get_dqinfo, |
2465 | .set_info = vfs_set_dqinfo, |
2466 | .get_dqblk = vfs_get_dqblk, |
2467 | .set_dqblk = vfs_set_dqblk |
2468 | }; |
2469 | |
2470 | static ctl_table fs_dqstats_table[] = { |
2471 | { |
2472 | .procname = "lookups", |
2473 | .data = &dqstats.lookups, |
2474 | .maxlen = sizeof(int), |
2475 | .mode = 0444, |
2476 | .proc_handler = proc_dointvec, |
2477 | }, |
2478 | { |
2479 | .procname = "drops", |
2480 | .data = &dqstats.drops, |
2481 | .maxlen = sizeof(int), |
2482 | .mode = 0444, |
2483 | .proc_handler = proc_dointvec, |
2484 | }, |
2485 | { |
2486 | .procname = "reads", |
2487 | .data = &dqstats.reads, |
2488 | .maxlen = sizeof(int), |
2489 | .mode = 0444, |
2490 | .proc_handler = proc_dointvec, |
2491 | }, |
2492 | { |
2493 | .procname = "writes", |
2494 | .data = &dqstats.writes, |
2495 | .maxlen = sizeof(int), |
2496 | .mode = 0444, |
2497 | .proc_handler = proc_dointvec, |
2498 | }, |
2499 | { |
2500 | .procname = "cache_hits", |
2501 | .data = &dqstats.cache_hits, |
2502 | .maxlen = sizeof(int), |
2503 | .mode = 0444, |
2504 | .proc_handler = proc_dointvec, |
2505 | }, |
2506 | { |
2507 | .procname = "allocated_dquots", |
2508 | .data = &dqstats.allocated_dquots, |
2509 | .maxlen = sizeof(int), |
2510 | .mode = 0444, |
2511 | .proc_handler = proc_dointvec, |
2512 | }, |
2513 | { |
2514 | .procname = "free_dquots", |
2515 | .data = &dqstats.free_dquots, |
2516 | .maxlen = sizeof(int), |
2517 | .mode = 0444, |
2518 | .proc_handler = proc_dointvec, |
2519 | }, |
2520 | { |
2521 | .procname = "syncs", |
2522 | .data = &dqstats.syncs, |
2523 | .maxlen = sizeof(int), |
2524 | .mode = 0444, |
2525 | .proc_handler = proc_dointvec, |
2526 | }, |
2527 | #ifdef CONFIG_PRINT_QUOTA_WARNING |
2528 | { |
2529 | .procname = "warnings", |
2530 | .data = &flag_print_warnings, |
2531 | .maxlen = sizeof(int), |
2532 | .mode = 0644, |
2533 | .proc_handler = proc_dointvec, |
2534 | }, |
2535 | #endif |
2536 | { }, |
2537 | }; |
2538 | |
2539 | static ctl_table fs_table[] = { |
2540 | { |
2541 | .procname = "quota", |
2542 | .mode = 0555, |
2543 | .child = fs_dqstats_table, |
2544 | }, |
2545 | { }, |
2546 | }; |
2547 | |
2548 | static ctl_table sys_table[] = { |
2549 | { |
2550 | .procname = "fs", |
2551 | .mode = 0555, |
2552 | .child = fs_table, |
2553 | }, |
2554 | { }, |
2555 | }; |
2556 | |
2557 | static int __init dquot_init(void) |
2558 | { |
2559 | int i; |
2560 | unsigned long nr_hash, order; |
2561 | |
2562 | printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); |
2563 | |
2564 | register_sysctl_table(sys_table); |
2565 | |
2566 | dquot_cachep = kmem_cache_create("dquot", |
2567 | sizeof(struct dquot), sizeof(unsigned long) * 4, |
2568 | (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| |
2569 | SLAB_MEM_SPREAD|SLAB_PANIC), |
2570 | NULL); |
2571 | |
2572 | order = 0; |
2573 | dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); |
2574 | if (!dquot_hash) |
2575 | panic("Cannot create dquot hash table"); |
2576 | |
2577 | /* Find power-of-two hlist_heads which can fit into allocation */ |
2578 | nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); |
2579 | dq_hash_bits = 0; |
2580 | do { |
2581 | dq_hash_bits++; |
2582 | } while (nr_hash >> dq_hash_bits); |
2583 | dq_hash_bits--; |
2584 | |
2585 | nr_hash = 1UL << dq_hash_bits; |
2586 | dq_hash_mask = nr_hash - 1; |
2587 | for (i = 0; i < nr_hash; i++) |
2588 | INIT_HLIST_HEAD(dquot_hash + i); |
2589 | |
2590 | printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", |
2591 | nr_hash, order, (PAGE_SIZE << order)); |
2592 | |
2593 | register_shrinker(&dqcache_shrinker); |
2594 | |
2595 | return 0; |
2596 | } |
2597 | module_init(dquot_init); |
2598 |
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