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1da177e4 LT |
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> | |
16f7e0fe | 80 | #include <linux/capability.h> |
be586bab | 81 | #include <linux/quotaops.h> |
1da177e4 LT |
82 | |
83 | #include <asm/uaccess.h> | |
84 | ||
85 | #define __DQUOT_PARANOIA | |
86 | ||
87 | /* | |
88 | * There are two quota SMP locks. dq_list_lock protects all lists with quotas | |
89 | * and quota formats and also dqstats structure containing statistics about the | |
90 | * lists. dq_data_lock protects data from dq_dqb and also mem_dqinfo structures | |
91 | * and also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes. | |
92 | * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly | |
93 | * in inode_add_bytes() and inode_sub_bytes(). | |
94 | * | |
95 | * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock | |
96 | * | |
97 | * Note that some things (eg. sb pointer, type, id) doesn't change during | |
98 | * the life of the dquot structure and so needn't to be protected by a lock | |
99 | * | |
100 | * Any operation working on dquots via inode pointers must hold dqptr_sem. If | |
101 | * operation is just reading pointers from inode (or not using them at all) the | |
102 | * read lock is enough. If pointers are altered function must hold write lock | |
103 | * (these locking rules also apply for S_NOQUOTA flag in the inode - note that | |
1b1dcc1b | 104 | * for altering the flag i_mutex is also needed). If operation is holding |
1da177e4 | 105 | * reference to dquot in other way (e.g. quotactl ops) it must be guarded by |
d3be915f | 106 | * dqonoff_mutex. |
1da177e4 LT |
107 | * This locking assures that: |
108 | * a) update/access to dquot pointers in inode is serialized | |
109 | * b) everyone is guarded against invalidate_dquots() | |
110 | * | |
d3be915f | 111 | * Each dquot has its dq_lock mutex. Locked dquots might not be referenced |
1da177e4 LT |
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: | |
d3be915f IM |
121 | * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock > |
122 | * dqio_mutex | |
123 | * i_mutex on quota files is special (it's below dqio_mutex) | |
1da177e4 LT |
124 | */ |
125 | ||
126 | static DEFINE_SPINLOCK(dq_list_lock); | |
127 | DEFINE_SPINLOCK(dq_data_lock); | |
128 | ||
129 | static char *quotatypes[] = INITQFNAMES; | |
130 | static struct quota_format_type *quota_formats; /* List of registered formats */ | |
131 | static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES; | |
132 | ||
133 | /* SLAB cache for dquot structures */ | |
134 | static kmem_cache_t *dquot_cachep; | |
135 | ||
136 | int register_quota_format(struct quota_format_type *fmt) | |
137 | { | |
138 | spin_lock(&dq_list_lock); | |
139 | fmt->qf_next = quota_formats; | |
140 | quota_formats = fmt; | |
141 | spin_unlock(&dq_list_lock); | |
142 | return 0; | |
143 | } | |
144 | ||
145 | void unregister_quota_format(struct quota_format_type *fmt) | |
146 | { | |
147 | struct quota_format_type **actqf; | |
148 | ||
149 | spin_lock(&dq_list_lock); | |
150 | for (actqf = "a_formats; *actqf && *actqf != fmt; actqf = &(*actqf)->qf_next); | |
151 | if (*actqf) | |
152 | *actqf = (*actqf)->qf_next; | |
153 | spin_unlock(&dq_list_lock); | |
154 | } | |
155 | ||
156 | static struct quota_format_type *find_quota_format(int id) | |
157 | { | |
158 | struct quota_format_type *actqf; | |
159 | ||
160 | spin_lock(&dq_list_lock); | |
161 | for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next); | |
162 | if (!actqf || !try_module_get(actqf->qf_owner)) { | |
163 | int qm; | |
164 | ||
165 | spin_unlock(&dq_list_lock); | |
166 | ||
167 | for (qm = 0; module_names[qm].qm_fmt_id && module_names[qm].qm_fmt_id != id; qm++); | |
168 | if (!module_names[qm].qm_fmt_id || request_module(module_names[qm].qm_mod_name)) | |
169 | return NULL; | |
170 | ||
171 | spin_lock(&dq_list_lock); | |
172 | for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next); | |
173 | if (actqf && !try_module_get(actqf->qf_owner)) | |
174 | actqf = NULL; | |
175 | } | |
176 | spin_unlock(&dq_list_lock); | |
177 | return actqf; | |
178 | } | |
179 | ||
180 | static void put_quota_format(struct quota_format_type *fmt) | |
181 | { | |
182 | module_put(fmt->qf_owner); | |
183 | } | |
184 | ||
185 | /* | |
186 | * Dquot List Management: | |
187 | * The quota code uses three lists for dquot management: the inuse_list, | |
188 | * free_dquots, and dquot_hash[] array. A single dquot structure may be | |
189 | * on all three lists, depending on its current state. | |
190 | * | |
191 | * All dquots are placed to the end of inuse_list when first created, and this | |
192 | * list is used for invalidate operation, which must look at every dquot. | |
193 | * | |
194 | * Unused dquots (dq_count == 0) are added to the free_dquots list when freed, | |
195 | * and this list is searched whenever we need an available dquot. Dquots are | |
196 | * removed from the list as soon as they are used again, and | |
197 | * dqstats.free_dquots gives the number of dquots on the list. When | |
198 | * dquot is invalidated it's completely released from memory. | |
199 | * | |
200 | * Dquots with a specific identity (device, type and id) are placed on | |
201 | * one of the dquot_hash[] hash chains. The provides an efficient search | |
202 | * mechanism to locate a specific dquot. | |
203 | */ | |
204 | ||
205 | static LIST_HEAD(inuse_list); | |
206 | static LIST_HEAD(free_dquots); | |
207 | static unsigned int dq_hash_bits, dq_hash_mask; | |
208 | static struct hlist_head *dquot_hash; | |
209 | ||
210 | struct dqstats dqstats; | |
211 | ||
212 | static void dqput(struct dquot *dquot); | |
213 | ||
214 | static inline unsigned int | |
215 | hashfn(const struct super_block *sb, unsigned int id, int type) | |
216 | { | |
217 | unsigned long tmp; | |
218 | ||
219 | tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type); | |
220 | return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask; | |
221 | } | |
222 | ||
223 | /* | |
224 | * Following list functions expect dq_list_lock to be held | |
225 | */ | |
226 | static inline void insert_dquot_hash(struct dquot *dquot) | |
227 | { | |
228 | struct hlist_head *head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type); | |
229 | hlist_add_head(&dquot->dq_hash, head); | |
230 | } | |
231 | ||
232 | static inline void remove_dquot_hash(struct dquot *dquot) | |
233 | { | |
234 | hlist_del_init(&dquot->dq_hash); | |
235 | } | |
236 | ||
237 | static inline struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, unsigned int id, int type) | |
238 | { | |
239 | struct hlist_node *node; | |
240 | struct dquot *dquot; | |
241 | ||
242 | hlist_for_each (node, dquot_hash+hashent) { | |
243 | dquot = hlist_entry(node, struct dquot, dq_hash); | |
244 | if (dquot->dq_sb == sb && dquot->dq_id == id && dquot->dq_type == type) | |
245 | return dquot; | |
246 | } | |
247 | return NODQUOT; | |
248 | } | |
249 | ||
250 | /* Add a dquot to the tail of the free list */ | |
251 | static inline void put_dquot_last(struct dquot *dquot) | |
252 | { | |
253 | list_add(&dquot->dq_free, free_dquots.prev); | |
254 | dqstats.free_dquots++; | |
255 | } | |
256 | ||
257 | static inline void remove_free_dquot(struct dquot *dquot) | |
258 | { | |
259 | if (list_empty(&dquot->dq_free)) | |
260 | return; | |
261 | list_del_init(&dquot->dq_free); | |
262 | dqstats.free_dquots--; | |
263 | } | |
264 | ||
265 | static inline void put_inuse(struct dquot *dquot) | |
266 | { | |
267 | /* We add to the back of inuse list so we don't have to restart | |
268 | * when traversing this list and we block */ | |
269 | list_add(&dquot->dq_inuse, inuse_list.prev); | |
270 | dqstats.allocated_dquots++; | |
271 | } | |
272 | ||
273 | static inline void remove_inuse(struct dquot *dquot) | |
274 | { | |
275 | dqstats.allocated_dquots--; | |
276 | list_del(&dquot->dq_inuse); | |
277 | } | |
278 | /* | |
279 | * End of list functions needing dq_list_lock | |
280 | */ | |
281 | ||
282 | static void wait_on_dquot(struct dquot *dquot) | |
283 | { | |
d3be915f IM |
284 | mutex_lock(&dquot->dq_lock); |
285 | mutex_unlock(&dquot->dq_lock); | |
1da177e4 LT |
286 | } |
287 | ||
288 | #define mark_dquot_dirty(dquot) ((dquot)->dq_sb->dq_op->mark_dirty(dquot)) | |
289 | ||
290 | int dquot_mark_dquot_dirty(struct dquot *dquot) | |
291 | { | |
292 | spin_lock(&dq_list_lock); | |
293 | if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) | |
294 | list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)-> | |
295 | info[dquot->dq_type].dqi_dirty_list); | |
296 | spin_unlock(&dq_list_lock); | |
297 | return 0; | |
298 | } | |
299 | ||
300 | /* This function needs dq_list_lock */ | |
301 | static inline int clear_dquot_dirty(struct dquot *dquot) | |
302 | { | |
303 | if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) | |
304 | return 0; | |
305 | list_del_init(&dquot->dq_dirty); | |
306 | return 1; | |
307 | } | |
308 | ||
309 | void mark_info_dirty(struct super_block *sb, int type) | |
310 | { | |
311 | set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags); | |
312 | } | |
313 | EXPORT_SYMBOL(mark_info_dirty); | |
314 | ||
315 | /* | |
316 | * Read dquot from disk and alloc space for it | |
317 | */ | |
318 | ||
319 | int dquot_acquire(struct dquot *dquot) | |
320 | { | |
321 | int ret = 0, ret2 = 0; | |
322 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); | |
323 | ||
d3be915f IM |
324 | mutex_lock(&dquot->dq_lock); |
325 | mutex_lock(&dqopt->dqio_mutex); | |
1da177e4 LT |
326 | if (!test_bit(DQ_READ_B, &dquot->dq_flags)) |
327 | ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot); | |
328 | if (ret < 0) | |
329 | goto out_iolock; | |
330 | set_bit(DQ_READ_B, &dquot->dq_flags); | |
331 | /* Instantiate dquot if needed */ | |
332 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) { | |
333 | ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); | |
334 | /* Write the info if needed */ | |
335 | if (info_dirty(&dqopt->info[dquot->dq_type])) | |
336 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type); | |
337 | if (ret < 0) | |
338 | goto out_iolock; | |
339 | if (ret2 < 0) { | |
340 | ret = ret2; | |
341 | goto out_iolock; | |
342 | } | |
343 | } | |
344 | set_bit(DQ_ACTIVE_B, &dquot->dq_flags); | |
345 | out_iolock: | |
d3be915f IM |
346 | mutex_unlock(&dqopt->dqio_mutex); |
347 | mutex_unlock(&dquot->dq_lock); | |
1da177e4 LT |
348 | return ret; |
349 | } | |
350 | ||
351 | /* | |
352 | * Write dquot to disk | |
353 | */ | |
354 | int dquot_commit(struct dquot *dquot) | |
355 | { | |
356 | int ret = 0, ret2 = 0; | |
357 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); | |
358 | ||
d3be915f | 359 | mutex_lock(&dqopt->dqio_mutex); |
1da177e4 LT |
360 | spin_lock(&dq_list_lock); |
361 | if (!clear_dquot_dirty(dquot)) { | |
362 | spin_unlock(&dq_list_lock); | |
363 | goto out_sem; | |
364 | } | |
365 | spin_unlock(&dq_list_lock); | |
366 | /* Inactive dquot can be only if there was error during read/init | |
367 | * => we have better not writing it */ | |
368 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { | |
369 | ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); | |
370 | if (info_dirty(&dqopt->info[dquot->dq_type])) | |
371 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type); | |
372 | if (ret >= 0) | |
373 | ret = ret2; | |
374 | } | |
375 | out_sem: | |
d3be915f | 376 | mutex_unlock(&dqopt->dqio_mutex); |
1da177e4 LT |
377 | return ret; |
378 | } | |
379 | ||
380 | /* | |
381 | * Release dquot | |
382 | */ | |
383 | int dquot_release(struct dquot *dquot) | |
384 | { | |
385 | int ret = 0, ret2 = 0; | |
386 | struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); | |
387 | ||
d3be915f | 388 | mutex_lock(&dquot->dq_lock); |
1da177e4 LT |
389 | /* Check whether we are not racing with some other dqget() */ |
390 | if (atomic_read(&dquot->dq_count) > 1) | |
391 | goto out_dqlock; | |
d3be915f | 392 | mutex_lock(&dqopt->dqio_mutex); |
1da177e4 LT |
393 | if (dqopt->ops[dquot->dq_type]->release_dqblk) { |
394 | ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot); | |
395 | /* Write the info */ | |
396 | if (info_dirty(&dqopt->info[dquot->dq_type])) | |
397 | ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type); | |
398 | if (ret >= 0) | |
399 | ret = ret2; | |
400 | } | |
401 | clear_bit(DQ_ACTIVE_B, &dquot->dq_flags); | |
d3be915f | 402 | mutex_unlock(&dqopt->dqio_mutex); |
1da177e4 | 403 | out_dqlock: |
d3be915f | 404 | mutex_unlock(&dquot->dq_lock); |
1da177e4 LT |
405 | return ret; |
406 | } | |
407 | ||
408 | /* Invalidate all dquots on the list. Note that this function is called after | |
409 | * quota is disabled and pointers from inodes removed so there cannot be new | |
6362e4d4 JK |
410 | * quota users. There can still be some users of quotas due to inodes being |
411 | * just deleted or pruned by prune_icache() (those are not attached to any | |
412 | * list). We have to wait for such users. | |
413 | */ | |
1da177e4 LT |
414 | static void invalidate_dquots(struct super_block *sb, int type) |
415 | { | |
c33ed271 | 416 | struct dquot *dquot, *tmp; |
1da177e4 | 417 | |
6362e4d4 | 418 | restart: |
1da177e4 | 419 | spin_lock(&dq_list_lock); |
c33ed271 | 420 | list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) { |
1da177e4 LT |
421 | if (dquot->dq_sb != sb) |
422 | continue; | |
423 | if (dquot->dq_type != type) | |
424 | continue; | |
6362e4d4 JK |
425 | /* Wait for dquot users */ |
426 | if (atomic_read(&dquot->dq_count)) { | |
427 | DEFINE_WAIT(wait); | |
428 | ||
429 | atomic_inc(&dquot->dq_count); | |
430 | prepare_to_wait(&dquot->dq_wait_unused, &wait, | |
431 | TASK_UNINTERRUPTIBLE); | |
432 | spin_unlock(&dq_list_lock); | |
433 | /* Once dqput() wakes us up, we know it's time to free | |
434 | * the dquot. | |
435 | * IMPORTANT: we rely on the fact that there is always | |
436 | * at most one process waiting for dquot to free. | |
437 | * Otherwise dq_count would be > 1 and we would never | |
438 | * wake up. | |
439 | */ | |
440 | if (atomic_read(&dquot->dq_count) > 1) | |
441 | schedule(); | |
442 | finish_wait(&dquot->dq_wait_unused, &wait); | |
443 | dqput(dquot); | |
444 | /* At this moment dquot() need not exist (it could be | |
445 | * reclaimed by prune_dqcache(). Hence we must | |
446 | * restart. */ | |
447 | goto restart; | |
448 | } | |
449 | /* | |
450 | * Quota now has no users and it has been written on last | |
451 | * dqput() | |
452 | */ | |
1da177e4 LT |
453 | remove_dquot_hash(dquot); |
454 | remove_free_dquot(dquot); | |
455 | remove_inuse(dquot); | |
456 | kmem_cache_free(dquot_cachep, dquot); | |
457 | } | |
458 | spin_unlock(&dq_list_lock); | |
459 | } | |
460 | ||
461 | int vfs_quota_sync(struct super_block *sb, int type) | |
462 | { | |
463 | struct list_head *dirty; | |
464 | struct dquot *dquot; | |
465 | struct quota_info *dqopt = sb_dqopt(sb); | |
466 | int cnt; | |
467 | ||
d3be915f | 468 | mutex_lock(&dqopt->dqonoff_mutex); |
1da177e4 LT |
469 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
470 | if (type != -1 && cnt != type) | |
471 | continue; | |
472 | if (!sb_has_quota_enabled(sb, cnt)) | |
473 | continue; | |
474 | spin_lock(&dq_list_lock); | |
475 | dirty = &dqopt->info[cnt].dqi_dirty_list; | |
476 | while (!list_empty(dirty)) { | |
477 | dquot = list_entry(dirty->next, struct dquot, dq_dirty); | |
478 | /* Dirty and inactive can be only bad dquot... */ | |
479 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { | |
480 | clear_dquot_dirty(dquot); | |
481 | continue; | |
482 | } | |
483 | /* Now we have active dquot from which someone is | |
484 | * holding reference so we can safely just increase | |
485 | * use count */ | |
486 | atomic_inc(&dquot->dq_count); | |
487 | dqstats.lookups++; | |
488 | spin_unlock(&dq_list_lock); | |
489 | sb->dq_op->write_dquot(dquot); | |
490 | dqput(dquot); | |
491 | spin_lock(&dq_list_lock); | |
492 | } | |
493 | spin_unlock(&dq_list_lock); | |
494 | } | |
495 | ||
496 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
497 | if ((cnt == type || type == -1) && sb_has_quota_enabled(sb, cnt) | |
498 | && info_dirty(&dqopt->info[cnt])) | |
499 | sb->dq_op->write_info(sb, cnt); | |
500 | spin_lock(&dq_list_lock); | |
501 | dqstats.syncs++; | |
502 | spin_unlock(&dq_list_lock); | |
d3be915f | 503 | mutex_unlock(&dqopt->dqonoff_mutex); |
1da177e4 LT |
504 | |
505 | return 0; | |
506 | } | |
507 | ||
508 | /* Free unused dquots from cache */ | |
509 | static void prune_dqcache(int count) | |
510 | { | |
511 | struct list_head *head; | |
512 | struct dquot *dquot; | |
513 | ||
514 | head = free_dquots.prev; | |
515 | while (head != &free_dquots && count) { | |
516 | dquot = list_entry(head, struct dquot, dq_free); | |
517 | remove_dquot_hash(dquot); | |
518 | remove_free_dquot(dquot); | |
519 | remove_inuse(dquot); | |
520 | kmem_cache_free(dquot_cachep, dquot); | |
521 | count--; | |
522 | head = free_dquots.prev; | |
523 | } | |
524 | } | |
525 | ||
526 | /* | |
527 | * This is called from kswapd when we think we need some | |
528 | * more memory | |
529 | */ | |
530 | ||
27496a8c | 531 | static int shrink_dqcache_memory(int nr, gfp_t gfp_mask) |
1da177e4 LT |
532 | { |
533 | if (nr) { | |
534 | spin_lock(&dq_list_lock); | |
535 | prune_dqcache(nr); | |
536 | spin_unlock(&dq_list_lock); | |
537 | } | |
538 | return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure; | |
539 | } | |
540 | ||
541 | /* | |
542 | * Put reference to dquot | |
543 | * NOTE: If you change this function please check whether dqput_blocks() works right... | |
d3be915f | 544 | * MUST be called with either dqptr_sem or dqonoff_mutex held |
1da177e4 LT |
545 | */ |
546 | static void dqput(struct dquot *dquot) | |
547 | { | |
548 | if (!dquot) | |
549 | return; | |
550 | #ifdef __DQUOT_PARANOIA | |
551 | if (!atomic_read(&dquot->dq_count)) { | |
552 | printk("VFS: dqput: trying to free free dquot\n"); | |
553 | printk("VFS: device %s, dquot of %s %d\n", | |
554 | dquot->dq_sb->s_id, | |
555 | quotatypes[dquot->dq_type], | |
556 | dquot->dq_id); | |
557 | BUG(); | |
558 | } | |
559 | #endif | |
560 | ||
561 | spin_lock(&dq_list_lock); | |
562 | dqstats.drops++; | |
563 | spin_unlock(&dq_list_lock); | |
564 | we_slept: | |
565 | spin_lock(&dq_list_lock); | |
566 | if (atomic_read(&dquot->dq_count) > 1) { | |
567 | /* We have more than one user... nothing to do */ | |
568 | atomic_dec(&dquot->dq_count); | |
6362e4d4 JK |
569 | /* Releasing dquot during quotaoff phase? */ |
570 | if (!sb_has_quota_enabled(dquot->dq_sb, dquot->dq_type) && | |
571 | atomic_read(&dquot->dq_count) == 1) | |
572 | wake_up(&dquot->dq_wait_unused); | |
1da177e4 LT |
573 | spin_unlock(&dq_list_lock); |
574 | return; | |
575 | } | |
576 | /* Need to release dquot? */ | |
577 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { | |
578 | spin_unlock(&dq_list_lock); | |
579 | /* Commit dquot before releasing */ | |
580 | dquot->dq_sb->dq_op->write_dquot(dquot); | |
581 | goto we_slept; | |
582 | } | |
583 | /* Clear flag in case dquot was inactive (something bad happened) */ | |
584 | clear_dquot_dirty(dquot); | |
585 | if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { | |
586 | spin_unlock(&dq_list_lock); | |
587 | dquot->dq_sb->dq_op->release_dquot(dquot); | |
588 | goto we_slept; | |
589 | } | |
590 | atomic_dec(&dquot->dq_count); | |
591 | #ifdef __DQUOT_PARANOIA | |
592 | /* sanity check */ | |
8abf6a47 | 593 | BUG_ON(!list_empty(&dquot->dq_free)); |
1da177e4 LT |
594 | #endif |
595 | put_dquot_last(dquot); | |
596 | spin_unlock(&dq_list_lock); | |
597 | } | |
598 | ||
599 | static struct dquot *get_empty_dquot(struct super_block *sb, int type) | |
600 | { | |
601 | struct dquot *dquot; | |
602 | ||
603 | dquot = kmem_cache_alloc(dquot_cachep, SLAB_NOFS); | |
604 | if(!dquot) | |
605 | return NODQUOT; | |
606 | ||
607 | memset((caddr_t)dquot, 0, sizeof(struct dquot)); | |
d3be915f | 608 | mutex_init(&dquot->dq_lock); |
1da177e4 LT |
609 | INIT_LIST_HEAD(&dquot->dq_free); |
610 | INIT_LIST_HEAD(&dquot->dq_inuse); | |
611 | INIT_HLIST_NODE(&dquot->dq_hash); | |
612 | INIT_LIST_HEAD(&dquot->dq_dirty); | |
6362e4d4 | 613 | init_waitqueue_head(&dquot->dq_wait_unused); |
1da177e4 LT |
614 | dquot->dq_sb = sb; |
615 | dquot->dq_type = type; | |
616 | atomic_set(&dquot->dq_count, 1); | |
617 | ||
618 | return dquot; | |
619 | } | |
620 | ||
621 | /* | |
622 | * Get reference to dquot | |
d3be915f | 623 | * MUST be called with either dqptr_sem or dqonoff_mutex held |
1da177e4 LT |
624 | */ |
625 | static struct dquot *dqget(struct super_block *sb, unsigned int id, int type) | |
626 | { | |
627 | unsigned int hashent = hashfn(sb, id, type); | |
628 | struct dquot *dquot, *empty = NODQUOT; | |
629 | ||
630 | if (!sb_has_quota_enabled(sb, type)) | |
631 | return NODQUOT; | |
632 | we_slept: | |
633 | spin_lock(&dq_list_lock); | |
634 | if ((dquot = find_dquot(hashent, sb, id, type)) == NODQUOT) { | |
635 | if (empty == NODQUOT) { | |
636 | spin_unlock(&dq_list_lock); | |
637 | if ((empty = get_empty_dquot(sb, type)) == NODQUOT) | |
638 | schedule(); /* Try to wait for a moment... */ | |
639 | goto we_slept; | |
640 | } | |
641 | dquot = empty; | |
642 | dquot->dq_id = id; | |
643 | /* all dquots go on the inuse_list */ | |
644 | put_inuse(dquot); | |
645 | /* hash it first so it can be found */ | |
646 | insert_dquot_hash(dquot); | |
647 | dqstats.lookups++; | |
648 | spin_unlock(&dq_list_lock); | |
649 | } else { | |
650 | if (!atomic_read(&dquot->dq_count)) | |
651 | remove_free_dquot(dquot); | |
652 | atomic_inc(&dquot->dq_count); | |
653 | dqstats.cache_hits++; | |
654 | dqstats.lookups++; | |
655 | spin_unlock(&dq_list_lock); | |
656 | if (empty) | |
657 | kmem_cache_free(dquot_cachep, empty); | |
658 | } | |
659 | /* Wait for dq_lock - after this we know that either dquot_release() is already | |
660 | * finished or it will be canceled due to dq_count > 1 test */ | |
661 | wait_on_dquot(dquot); | |
662 | /* Read the dquot and instantiate it (everything done only if needed) */ | |
663 | if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && sb->dq_op->acquire_dquot(dquot) < 0) { | |
664 | dqput(dquot); | |
665 | return NODQUOT; | |
666 | } | |
667 | #ifdef __DQUOT_PARANOIA | |
8abf6a47 | 668 | BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ |
1da177e4 LT |
669 | #endif |
670 | ||
671 | return dquot; | |
672 | } | |
673 | ||
674 | static int dqinit_needed(struct inode *inode, int type) | |
675 | { | |
676 | int cnt; | |
677 | ||
678 | if (IS_NOQUOTA(inode)) | |
679 | return 0; | |
680 | if (type != -1) | |
681 | return inode->i_dquot[type] == NODQUOT; | |
682 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
683 | if (inode->i_dquot[cnt] == NODQUOT) | |
684 | return 1; | |
685 | return 0; | |
686 | } | |
687 | ||
d3be915f | 688 | /* This routine is guarded by dqonoff_mutex mutex */ |
1da177e4 LT |
689 | static void add_dquot_ref(struct super_block *sb, int type) |
690 | { | |
691 | struct list_head *p; | |
692 | ||
693 | restart: | |
694 | file_list_lock(); | |
695 | list_for_each(p, &sb->s_files) { | |
2f512016 | 696 | struct file *filp = list_entry(p, struct file, f_u.fu_list); |
1da177e4 LT |
697 | struct inode *inode = filp->f_dentry->d_inode; |
698 | if (filp->f_mode & FMODE_WRITE && dqinit_needed(inode, type)) { | |
699 | struct dentry *dentry = dget(filp->f_dentry); | |
700 | file_list_unlock(); | |
701 | sb->dq_op->initialize(inode, type); | |
702 | dput(dentry); | |
703 | /* As we may have blocked we had better restart... */ | |
704 | goto restart; | |
705 | } | |
706 | } | |
707 | file_list_unlock(); | |
708 | } | |
709 | ||
710 | /* Return 0 if dqput() won't block (note that 1 doesn't necessarily mean blocking) */ | |
711 | static inline int dqput_blocks(struct dquot *dquot) | |
712 | { | |
713 | if (atomic_read(&dquot->dq_count) <= 1) | |
714 | return 1; | |
715 | return 0; | |
716 | } | |
717 | ||
718 | /* Remove references to dquots from inode - add dquot to list for freeing if needed */ | |
719 | /* We can't race with anybody because we hold dqptr_sem for writing... */ | |
720 | int remove_inode_dquot_ref(struct inode *inode, int type, struct list_head *tofree_head) | |
721 | { | |
722 | struct dquot *dquot = inode->i_dquot[type]; | |
723 | ||
724 | inode->i_dquot[type] = NODQUOT; | |
725 | if (dquot != NODQUOT) { | |
726 | if (dqput_blocks(dquot)) { | |
727 | #ifdef __DQUOT_PARANOIA | |
728 | if (atomic_read(&dquot->dq_count) != 1) | |
729 | printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count)); | |
730 | #endif | |
731 | spin_lock(&dq_list_lock); | |
732 | list_add(&dquot->dq_free, tofree_head); /* As dquot must have currently users it can't be on the free list... */ | |
733 | spin_unlock(&dq_list_lock); | |
734 | return 1; | |
735 | } | |
736 | else | |
737 | dqput(dquot); /* We have guaranteed we won't block */ | |
738 | } | |
739 | return 0; | |
740 | } | |
741 | ||
742 | /* Free list of dquots - called from inode.c */ | |
743 | /* dquots are removed from inodes, no new references can be got so we are the only ones holding reference */ | |
744 | static void put_dquot_list(struct list_head *tofree_head) | |
745 | { | |
746 | struct list_head *act_head; | |
747 | struct dquot *dquot; | |
748 | ||
749 | act_head = tofree_head->next; | |
750 | /* So now we have dquots on the list... Just free them */ | |
751 | while (act_head != tofree_head) { | |
752 | dquot = list_entry(act_head, struct dquot, dq_free); | |
753 | act_head = act_head->next; | |
754 | list_del_init(&dquot->dq_free); /* Remove dquot from the list so we won't have problems... */ | |
755 | dqput(dquot); | |
756 | } | |
757 | } | |
758 | ||
759 | /* Gather all references from inodes and drop them */ | |
760 | static void drop_dquot_ref(struct super_block *sb, int type) | |
761 | { | |
762 | LIST_HEAD(tofree_head); | |
763 | ||
1da177e4 LT |
764 | down_write(&sb_dqopt(sb)->dqptr_sem); |
765 | remove_dquot_ref(sb, type, &tofree_head); | |
766 | up_write(&sb_dqopt(sb)->dqptr_sem); | |
1da177e4 LT |
767 | put_dquot_list(&tofree_head); |
768 | } | |
769 | ||
770 | static inline void dquot_incr_inodes(struct dquot *dquot, unsigned long number) | |
771 | { | |
772 | dquot->dq_dqb.dqb_curinodes += number; | |
773 | } | |
774 | ||
775 | static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) | |
776 | { | |
777 | dquot->dq_dqb.dqb_curspace += number; | |
778 | } | |
779 | ||
780 | static inline void dquot_decr_inodes(struct dquot *dquot, unsigned long number) | |
781 | { | |
782 | if (dquot->dq_dqb.dqb_curinodes > number) | |
783 | dquot->dq_dqb.dqb_curinodes -= number; | |
784 | else | |
785 | dquot->dq_dqb.dqb_curinodes = 0; | |
786 | if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) | |
787 | dquot->dq_dqb.dqb_itime = (time_t) 0; | |
788 | clear_bit(DQ_INODES_B, &dquot->dq_flags); | |
789 | } | |
790 | ||
791 | static inline void dquot_decr_space(struct dquot *dquot, qsize_t number) | |
792 | { | |
793 | if (dquot->dq_dqb.dqb_curspace > number) | |
794 | dquot->dq_dqb.dqb_curspace -= number; | |
795 | else | |
796 | dquot->dq_dqb.dqb_curspace = 0; | |
797 | if (toqb(dquot->dq_dqb.dqb_curspace) <= dquot->dq_dqb.dqb_bsoftlimit) | |
798 | dquot->dq_dqb.dqb_btime = (time_t) 0; | |
799 | clear_bit(DQ_BLKS_B, &dquot->dq_flags); | |
800 | } | |
801 | ||
802 | static int flag_print_warnings = 1; | |
803 | ||
804 | static inline int need_print_warning(struct dquot *dquot) | |
805 | { | |
806 | if (!flag_print_warnings) | |
807 | return 0; | |
808 | ||
809 | switch (dquot->dq_type) { | |
810 | case USRQUOTA: | |
811 | return current->fsuid == dquot->dq_id; | |
812 | case GRPQUOTA: | |
813 | return in_group_p(dquot->dq_id); | |
814 | } | |
815 | return 0; | |
816 | } | |
817 | ||
818 | /* Values of warnings */ | |
819 | #define NOWARN 0 | |
820 | #define IHARDWARN 1 | |
821 | #define ISOFTLONGWARN 2 | |
822 | #define ISOFTWARN 3 | |
823 | #define BHARDWARN 4 | |
824 | #define BSOFTLONGWARN 5 | |
825 | #define BSOFTWARN 6 | |
826 | ||
827 | /* Print warning to user which exceeded quota */ | |
828 | static void print_warning(struct dquot *dquot, const char warntype) | |
829 | { | |
830 | char *msg = NULL; | |
831 | int flag = (warntype == BHARDWARN || warntype == BSOFTLONGWARN) ? DQ_BLKS_B : | |
832 | ((warntype == IHARDWARN || warntype == ISOFTLONGWARN) ? DQ_INODES_B : 0); | |
833 | ||
834 | if (!need_print_warning(dquot) || (flag && test_and_set_bit(flag, &dquot->dq_flags))) | |
835 | return; | |
836 | ||
837 | tty_write_message(current->signal->tty, dquot->dq_sb->s_id); | |
838 | if (warntype == ISOFTWARN || warntype == BSOFTWARN) | |
839 | tty_write_message(current->signal->tty, ": warning, "); | |
840 | else | |
841 | tty_write_message(current->signal->tty, ": write failed, "); | |
842 | tty_write_message(current->signal->tty, quotatypes[dquot->dq_type]); | |
843 | switch (warntype) { | |
844 | case IHARDWARN: | |
845 | msg = " file limit reached.\r\n"; | |
846 | break; | |
847 | case ISOFTLONGWARN: | |
848 | msg = " file quota exceeded too long.\r\n"; | |
849 | break; | |
850 | case ISOFTWARN: | |
851 | msg = " file quota exceeded.\r\n"; | |
852 | break; | |
853 | case BHARDWARN: | |
854 | msg = " block limit reached.\r\n"; | |
855 | break; | |
856 | case BSOFTLONGWARN: | |
857 | msg = " block quota exceeded too long.\r\n"; | |
858 | break; | |
859 | case BSOFTWARN: | |
860 | msg = " block quota exceeded.\r\n"; | |
861 | break; | |
862 | } | |
863 | tty_write_message(current->signal->tty, msg); | |
864 | } | |
865 | ||
866 | static inline void flush_warnings(struct dquot **dquots, char *warntype) | |
867 | { | |
868 | int i; | |
869 | ||
870 | for (i = 0; i < MAXQUOTAS; i++) | |
871 | if (dquots[i] != NODQUOT && warntype[i] != NOWARN) | |
872 | print_warning(dquots[i], warntype[i]); | |
873 | } | |
874 | ||
875 | static inline char ignore_hardlimit(struct dquot *dquot) | |
876 | { | |
877 | struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; | |
878 | ||
879 | return capable(CAP_SYS_RESOURCE) && | |
880 | (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || !(info->dqi_flags & V1_DQF_RSQUASH)); | |
881 | } | |
882 | ||
883 | /* needs dq_data_lock */ | |
884 | static int check_idq(struct dquot *dquot, ulong inodes, char *warntype) | |
885 | { | |
886 | *warntype = NOWARN; | |
887 | if (inodes <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags)) | |
888 | return QUOTA_OK; | |
889 | ||
890 | if (dquot->dq_dqb.dqb_ihardlimit && | |
891 | (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_ihardlimit && | |
892 | !ignore_hardlimit(dquot)) { | |
893 | *warntype = IHARDWARN; | |
894 | return NO_QUOTA; | |
895 | } | |
896 | ||
897 | if (dquot->dq_dqb.dqb_isoftlimit && | |
898 | (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit && | |
899 | dquot->dq_dqb.dqb_itime && get_seconds() >= dquot->dq_dqb.dqb_itime && | |
900 | !ignore_hardlimit(dquot)) { | |
901 | *warntype = ISOFTLONGWARN; | |
902 | return NO_QUOTA; | |
903 | } | |
904 | ||
905 | if (dquot->dq_dqb.dqb_isoftlimit && | |
906 | (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit && | |
907 | dquot->dq_dqb.dqb_itime == 0) { | |
908 | *warntype = ISOFTWARN; | |
909 | dquot->dq_dqb.dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; | |
910 | } | |
911 | ||
912 | return QUOTA_OK; | |
913 | } | |
914 | ||
915 | /* needs dq_data_lock */ | |
916 | static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) | |
917 | { | |
918 | *warntype = 0; | |
919 | if (space <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags)) | |
920 | return QUOTA_OK; | |
921 | ||
922 | if (dquot->dq_dqb.dqb_bhardlimit && | |
923 | toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bhardlimit && | |
924 | !ignore_hardlimit(dquot)) { | |
925 | if (!prealloc) | |
926 | *warntype = BHARDWARN; | |
927 | return NO_QUOTA; | |
928 | } | |
929 | ||
930 | if (dquot->dq_dqb.dqb_bsoftlimit && | |
931 | toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit && | |
932 | dquot->dq_dqb.dqb_btime && get_seconds() >= dquot->dq_dqb.dqb_btime && | |
933 | !ignore_hardlimit(dquot)) { | |
934 | if (!prealloc) | |
935 | *warntype = BSOFTLONGWARN; | |
936 | return NO_QUOTA; | |
937 | } | |
938 | ||
939 | if (dquot->dq_dqb.dqb_bsoftlimit && | |
940 | toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit && | |
941 | dquot->dq_dqb.dqb_btime == 0) { | |
942 | if (!prealloc) { | |
943 | *warntype = BSOFTWARN; | |
944 | dquot->dq_dqb.dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace; | |
945 | } | |
946 | else | |
947 | /* | |
948 | * We don't allow preallocation to exceed softlimit so exceeding will | |
949 | * be always printed | |
950 | */ | |
951 | return NO_QUOTA; | |
952 | } | |
953 | ||
954 | return QUOTA_OK; | |
955 | } | |
956 | ||
957 | /* | |
958 | * Initialize quota pointers in inode | |
959 | * Transaction must be started at entry | |
960 | */ | |
961 | int dquot_initialize(struct inode *inode, int type) | |
962 | { | |
963 | unsigned int id = 0; | |
964 | int cnt, ret = 0; | |
965 | ||
d3be915f IM |
966 | /* First test before acquiring mutex - solves deadlocks when we |
967 | * re-enter the quota code and are already holding the mutex */ | |
1da177e4 LT |
968 | if (IS_NOQUOTA(inode)) |
969 | return 0; | |
970 | down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
971 | /* Having dqptr_sem we know NOQUOTA flags can't be altered... */ | |
972 | if (IS_NOQUOTA(inode)) | |
973 | goto out_err; | |
974 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
975 | if (type != -1 && cnt != type) | |
976 | continue; | |
977 | if (inode->i_dquot[cnt] == NODQUOT) { | |
978 | switch (cnt) { | |
979 | case USRQUOTA: | |
980 | id = inode->i_uid; | |
981 | break; | |
982 | case GRPQUOTA: | |
983 | id = inode->i_gid; | |
984 | break; | |
985 | } | |
986 | inode->i_dquot[cnt] = dqget(inode->i_sb, id, cnt); | |
987 | } | |
988 | } | |
989 | out_err: | |
990 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
991 | return ret; | |
992 | } | |
993 | ||
994 | /* | |
995 | * Release all quotas referenced by inode | |
996 | * Transaction must be started at an entry | |
997 | */ | |
998 | int dquot_drop(struct inode *inode) | |
999 | { | |
1000 | int cnt; | |
1001 | ||
1002 | down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1003 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1004 | if (inode->i_dquot[cnt] != NODQUOT) { | |
1005 | dqput(inode->i_dquot[cnt]); | |
1006 | inode->i_dquot[cnt] = NODQUOT; | |
1007 | } | |
1008 | } | |
1009 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1010 | return 0; | |
1011 | } | |
1012 | ||
1013 | /* | |
1014 | * Following four functions update i_blocks+i_bytes fields and | |
1015 | * quota information (together with appropriate checks) | |
1016 | * NOTE: We absolutely rely on the fact that caller dirties | |
1017 | * the inode (usually macros in quotaops.h care about this) and | |
1018 | * holds a handle for the current transaction so that dquot write and | |
1019 | * inode write go into the same transaction. | |
1020 | */ | |
1021 | ||
1022 | /* | |
1023 | * This operation can block, but only after everything is updated | |
1024 | */ | |
1025 | int dquot_alloc_space(struct inode *inode, qsize_t number, int warn) | |
1026 | { | |
1027 | int cnt, ret = NO_QUOTA; | |
1028 | char warntype[MAXQUOTAS]; | |
1029 | ||
d3be915f IM |
1030 | /* First test before acquiring mutex - solves deadlocks when we |
1031 | * re-enter the quota code and are already holding the mutex */ | |
1da177e4 LT |
1032 | if (IS_NOQUOTA(inode)) { |
1033 | out_add: | |
1034 | inode_add_bytes(inode, number); | |
1035 | return QUOTA_OK; | |
1036 | } | |
1037 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
1038 | warntype[cnt] = NOWARN; | |
1039 | ||
1040 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1041 | if (IS_NOQUOTA(inode)) { /* Now we can do reliable test... */ | |
1042 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1043 | goto out_add; | |
1044 | } | |
1045 | spin_lock(&dq_data_lock); | |
1046 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1047 | if (inode->i_dquot[cnt] == NODQUOT) | |
1048 | continue; | |
1049 | if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt) == NO_QUOTA) | |
1050 | goto warn_put_all; | |
1051 | } | |
1052 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1053 | if (inode->i_dquot[cnt] == NODQUOT) | |
1054 | continue; | |
1055 | dquot_incr_space(inode->i_dquot[cnt], number); | |
1056 | } | |
1057 | inode_add_bytes(inode, number); | |
1058 | ret = QUOTA_OK; | |
1059 | warn_put_all: | |
1060 | spin_unlock(&dq_data_lock); | |
1061 | if (ret == QUOTA_OK) | |
1062 | /* Dirtify all the dquots - this can block when journalling */ | |
1063 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
1064 | if (inode->i_dquot[cnt]) | |
1065 | mark_dquot_dirty(inode->i_dquot[cnt]); | |
1066 | flush_warnings(inode->i_dquot, warntype); | |
1067 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1068 | return ret; | |
1069 | } | |
1070 | ||
1071 | /* | |
1072 | * This operation can block, but only after everything is updated | |
1073 | */ | |
1074 | int dquot_alloc_inode(const struct inode *inode, unsigned long number) | |
1075 | { | |
1076 | int cnt, ret = NO_QUOTA; | |
1077 | char warntype[MAXQUOTAS]; | |
1078 | ||
d3be915f IM |
1079 | /* First test before acquiring mutex - solves deadlocks when we |
1080 | * re-enter the quota code and are already holding the mutex */ | |
1da177e4 LT |
1081 | if (IS_NOQUOTA(inode)) |
1082 | return QUOTA_OK; | |
1083 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
1084 | warntype[cnt] = NOWARN; | |
1085 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1086 | if (IS_NOQUOTA(inode)) { | |
1087 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1088 | return QUOTA_OK; | |
1089 | } | |
1090 | spin_lock(&dq_data_lock); | |
1091 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1092 | if (inode->i_dquot[cnt] == NODQUOT) | |
1093 | continue; | |
1094 | if (check_idq(inode->i_dquot[cnt], number, warntype+cnt) == NO_QUOTA) | |
1095 | goto warn_put_all; | |
1096 | } | |
1097 | ||
1098 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1099 | if (inode->i_dquot[cnt] == NODQUOT) | |
1100 | continue; | |
1101 | dquot_incr_inodes(inode->i_dquot[cnt], number); | |
1102 | } | |
1103 | ret = QUOTA_OK; | |
1104 | warn_put_all: | |
1105 | spin_unlock(&dq_data_lock); | |
1106 | if (ret == QUOTA_OK) | |
1107 | /* Dirtify all the dquots - this can block when journalling */ | |
1108 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
1109 | if (inode->i_dquot[cnt]) | |
1110 | mark_dquot_dirty(inode->i_dquot[cnt]); | |
1111 | flush_warnings((struct dquot **)inode->i_dquot, warntype); | |
1112 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1113 | return ret; | |
1114 | } | |
1115 | ||
1116 | /* | |
1117 | * This operation can block, but only after everything is updated | |
1118 | */ | |
1119 | int dquot_free_space(struct inode *inode, qsize_t number) | |
1120 | { | |
1121 | unsigned int cnt; | |
1122 | ||
d3be915f IM |
1123 | /* First test before acquiring mutex - solves deadlocks when we |
1124 | * re-enter the quota code and are already holding the mutex */ | |
1da177e4 LT |
1125 | if (IS_NOQUOTA(inode)) { |
1126 | out_sub: | |
1127 | inode_sub_bytes(inode, number); | |
1128 | return QUOTA_OK; | |
1129 | } | |
1130 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1131 | /* Now recheck reliably when holding dqptr_sem */ | |
1132 | if (IS_NOQUOTA(inode)) { | |
1133 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1134 | goto out_sub; | |
1135 | } | |
1136 | spin_lock(&dq_data_lock); | |
1137 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1138 | if (inode->i_dquot[cnt] == NODQUOT) | |
1139 | continue; | |
1140 | dquot_decr_space(inode->i_dquot[cnt], number); | |
1141 | } | |
1142 | inode_sub_bytes(inode, number); | |
1143 | spin_unlock(&dq_data_lock); | |
1144 | /* Dirtify all the dquots - this can block when journalling */ | |
1145 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
1146 | if (inode->i_dquot[cnt]) | |
1147 | mark_dquot_dirty(inode->i_dquot[cnt]); | |
1148 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1149 | return QUOTA_OK; | |
1150 | } | |
1151 | ||
1152 | /* | |
1153 | * This operation can block, but only after everything is updated | |
1154 | */ | |
1155 | int dquot_free_inode(const struct inode *inode, unsigned long number) | |
1156 | { | |
1157 | unsigned int cnt; | |
1158 | ||
d3be915f IM |
1159 | /* First test before acquiring mutex - solves deadlocks when we |
1160 | * re-enter the quota code and are already holding the mutex */ | |
1da177e4 LT |
1161 | if (IS_NOQUOTA(inode)) |
1162 | return QUOTA_OK; | |
1163 | down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1164 | /* Now recheck reliably when holding dqptr_sem */ | |
1165 | if (IS_NOQUOTA(inode)) { | |
1166 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1167 | return QUOTA_OK; | |
1168 | } | |
1169 | spin_lock(&dq_data_lock); | |
1170 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1171 | if (inode->i_dquot[cnt] == NODQUOT) | |
1172 | continue; | |
1173 | dquot_decr_inodes(inode->i_dquot[cnt], number); | |
1174 | } | |
1175 | spin_unlock(&dq_data_lock); | |
1176 | /* Dirtify all the dquots - this can block when journalling */ | |
1177 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
1178 | if (inode->i_dquot[cnt]) | |
1179 | mark_dquot_dirty(inode->i_dquot[cnt]); | |
1180 | up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1181 | return QUOTA_OK; | |
1182 | } | |
1183 | ||
1184 | /* | |
1185 | * Transfer the number of inode and blocks from one diskquota to an other. | |
1186 | * | |
1187 | * This operation can block, but only after everything is updated | |
1188 | * A transaction must be started when entering this function. | |
1189 | */ | |
1190 | int dquot_transfer(struct inode *inode, struct iattr *iattr) | |
1191 | { | |
1192 | qsize_t space; | |
1193 | struct dquot *transfer_from[MAXQUOTAS]; | |
1194 | struct dquot *transfer_to[MAXQUOTAS]; | |
1195 | int cnt, ret = NO_QUOTA, chuid = (iattr->ia_valid & ATTR_UID) && inode->i_uid != iattr->ia_uid, | |
1196 | chgid = (iattr->ia_valid & ATTR_GID) && inode->i_gid != iattr->ia_gid; | |
1197 | char warntype[MAXQUOTAS]; | |
1198 | ||
d3be915f IM |
1199 | /* First test before acquiring mutex - solves deadlocks when we |
1200 | * re-enter the quota code and are already holding the mutex */ | |
1da177e4 LT |
1201 | if (IS_NOQUOTA(inode)) |
1202 | return QUOTA_OK; | |
1203 | /* Clear the arrays */ | |
1204 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1205 | transfer_to[cnt] = transfer_from[cnt] = NODQUOT; | |
1206 | warntype[cnt] = NOWARN; | |
1207 | } | |
1208 | down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1209 | /* Now recheck reliably when holding dqptr_sem */ | |
1210 | if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ | |
1211 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1212 | return QUOTA_OK; | |
1213 | } | |
1214 | /* First build the transfer_to list - here we can block on | |
1215 | * reading/instantiating of dquots. We know that the transaction for | |
1216 | * us was already started so we don't violate lock ranking here */ | |
1217 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1218 | switch (cnt) { | |
1219 | case USRQUOTA: | |
1220 | if (!chuid) | |
1221 | continue; | |
1222 | transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_uid, cnt); | |
1223 | break; | |
1224 | case GRPQUOTA: | |
1225 | if (!chgid) | |
1226 | continue; | |
1227 | transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_gid, cnt); | |
1228 | break; | |
1229 | } | |
1230 | } | |
1231 | spin_lock(&dq_data_lock); | |
1232 | space = inode_get_bytes(inode); | |
1233 | /* Build the transfer_from list and check the limits */ | |
1234 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1235 | if (transfer_to[cnt] == NODQUOT) | |
1236 | continue; | |
1237 | transfer_from[cnt] = inode->i_dquot[cnt]; | |
1238 | if (check_idq(transfer_to[cnt], 1, warntype+cnt) == NO_QUOTA || | |
1239 | check_bdq(transfer_to[cnt], space, 0, warntype+cnt) == NO_QUOTA) | |
1240 | goto warn_put_all; | |
1241 | } | |
1242 | ||
1243 | /* | |
1244 | * Finally perform the needed transfer from transfer_from to transfer_to | |
1245 | */ | |
1246 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1247 | /* | |
1248 | * Skip changes for same uid or gid or for turned off quota-type. | |
1249 | */ | |
1250 | if (transfer_to[cnt] == NODQUOT) | |
1251 | continue; | |
1252 | ||
1253 | /* Due to IO error we might not have transfer_from[] structure */ | |
1254 | if (transfer_from[cnt]) { | |
1255 | dquot_decr_inodes(transfer_from[cnt], 1); | |
1256 | dquot_decr_space(transfer_from[cnt], space); | |
1257 | } | |
1258 | ||
1259 | dquot_incr_inodes(transfer_to[cnt], 1); | |
1260 | dquot_incr_space(transfer_to[cnt], space); | |
1261 | ||
1262 | inode->i_dquot[cnt] = transfer_to[cnt]; | |
1263 | } | |
1264 | ret = QUOTA_OK; | |
1265 | warn_put_all: | |
1266 | spin_unlock(&dq_data_lock); | |
1267 | /* Dirtify all the dquots - this can block when journalling */ | |
1268 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1269 | if (transfer_from[cnt]) | |
1270 | mark_dquot_dirty(transfer_from[cnt]); | |
1271 | if (transfer_to[cnt]) | |
1272 | mark_dquot_dirty(transfer_to[cnt]); | |
1273 | } | |
1274 | flush_warnings(transfer_to, warntype); | |
1275 | ||
1276 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { | |
1277 | if (ret == QUOTA_OK && transfer_from[cnt] != NODQUOT) | |
1278 | dqput(transfer_from[cnt]); | |
1279 | if (ret == NO_QUOTA && transfer_to[cnt] != NODQUOT) | |
1280 | dqput(transfer_to[cnt]); | |
1281 | } | |
1282 | up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); | |
1283 | return ret; | |
1284 | } | |
1285 | ||
1286 | /* | |
1287 | * Write info of quota file to disk | |
1288 | */ | |
1289 | int dquot_commit_info(struct super_block *sb, int type) | |
1290 | { | |
1291 | int ret; | |
1292 | struct quota_info *dqopt = sb_dqopt(sb); | |
1293 | ||
d3be915f | 1294 | mutex_lock(&dqopt->dqio_mutex); |
1da177e4 | 1295 | ret = dqopt->ops[type]->write_file_info(sb, type); |
d3be915f | 1296 | mutex_unlock(&dqopt->dqio_mutex); |
1da177e4 LT |
1297 | return ret; |
1298 | } | |
1299 | ||
1300 | /* | |
1301 | * Definitions of diskquota operations. | |
1302 | */ | |
1303 | struct dquot_operations dquot_operations = { | |
1304 | .initialize = dquot_initialize, | |
1305 | .drop = dquot_drop, | |
1306 | .alloc_space = dquot_alloc_space, | |
1307 | .alloc_inode = dquot_alloc_inode, | |
1308 | .free_space = dquot_free_space, | |
1309 | .free_inode = dquot_free_inode, | |
1310 | .transfer = dquot_transfer, | |
1311 | .write_dquot = dquot_commit, | |
1312 | .acquire_dquot = dquot_acquire, | |
1313 | .release_dquot = dquot_release, | |
1314 | .mark_dirty = dquot_mark_dquot_dirty, | |
1315 | .write_info = dquot_commit_info | |
1316 | }; | |
1317 | ||
1318 | static inline void set_enable_flags(struct quota_info *dqopt, int type) | |
1319 | { | |
1320 | switch (type) { | |
1321 | case USRQUOTA: | |
1322 | dqopt->flags |= DQUOT_USR_ENABLED; | |
1323 | break; | |
1324 | case GRPQUOTA: | |
1325 | dqopt->flags |= DQUOT_GRP_ENABLED; | |
1326 | break; | |
1327 | } | |
1328 | } | |
1329 | ||
1330 | static inline void reset_enable_flags(struct quota_info *dqopt, int type) | |
1331 | { | |
1332 | switch (type) { | |
1333 | case USRQUOTA: | |
1334 | dqopt->flags &= ~DQUOT_USR_ENABLED; | |
1335 | break; | |
1336 | case GRPQUOTA: | |
1337 | dqopt->flags &= ~DQUOT_GRP_ENABLED; | |
1338 | break; | |
1339 | } | |
1340 | } | |
1341 | ||
1342 | /* | |
1343 | * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) | |
1344 | */ | |
1345 | int vfs_quota_off(struct super_block *sb, int type) | |
1346 | { | |
1347 | int cnt; | |
1348 | struct quota_info *dqopt = sb_dqopt(sb); | |
1349 | struct inode *toputinode[MAXQUOTAS]; | |
1da177e4 LT |
1350 | |
1351 | /* We need to serialize quota_off() for device */ | |
d3be915f | 1352 | mutex_lock(&dqopt->dqonoff_mutex); |
1da177e4 LT |
1353 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) { |
1354 | toputinode[cnt] = NULL; | |
1da177e4 LT |
1355 | if (type != -1 && cnt != type) |
1356 | continue; | |
1357 | if (!sb_has_quota_enabled(sb, cnt)) | |
1358 | continue; | |
1359 | reset_enable_flags(dqopt, cnt); | |
1360 | ||
1361 | /* Note: these are blocking operations */ | |
1362 | drop_dquot_ref(sb, cnt); | |
1363 | invalidate_dquots(sb, cnt); | |
1364 | /* | |
1365 | * Now all dquots should be invalidated, all writes done so we should be only | |
1366 | * users of the info. No locks needed. | |
1367 | */ | |
1368 | if (info_dirty(&dqopt->info[cnt])) | |
1369 | sb->dq_op->write_info(sb, cnt); | |
1370 | if (dqopt->ops[cnt]->free_file_info) | |
1371 | dqopt->ops[cnt]->free_file_info(sb, cnt); | |
1372 | put_quota_format(dqopt->info[cnt].dqi_format); | |
1373 | ||
1374 | toputinode[cnt] = dqopt->files[cnt]; | |
1da177e4 | 1375 | dqopt->files[cnt] = NULL; |
1da177e4 LT |
1376 | dqopt->info[cnt].dqi_flags = 0; |
1377 | dqopt->info[cnt].dqi_igrace = 0; | |
1378 | dqopt->info[cnt].dqi_bgrace = 0; | |
1379 | dqopt->ops[cnt] = NULL; | |
1380 | } | |
d3be915f | 1381 | mutex_unlock(&dqopt->dqonoff_mutex); |
1da177e4 | 1382 | /* Sync the superblock so that buffers with quota data are written to |
7b7b1ace | 1383 | * disk (and so userspace sees correct data afterwards). */ |
1da177e4 LT |
1384 | if (sb->s_op->sync_fs) |
1385 | sb->s_op->sync_fs(sb, 1); | |
1386 | sync_blockdev(sb->s_bdev); | |
1387 | /* Now the quota files are just ordinary files and we can set the | |
1388 | * inode flags back. Moreover we discard the pagecache so that | |
1389 | * userspace sees the writes we did bypassing the pagecache. We | |
1390 | * must also discard the blockdev buffers so that we see the | |
1391 | * changes done by userspace on the next quotaon() */ | |
1392 | for (cnt = 0; cnt < MAXQUOTAS; cnt++) | |
1393 | if (toputinode[cnt]) { | |
d3be915f | 1394 | mutex_lock(&dqopt->dqonoff_mutex); |
1da177e4 LT |
1395 | /* If quota was reenabled in the meantime, we have |
1396 | * nothing to do */ | |
1397 | if (!sb_has_quota_enabled(sb, cnt)) { | |
1b1dcc1b | 1398 | mutex_lock(&toputinode[cnt]->i_mutex); |
1da177e4 LT |
1399 | toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | |
1400 | S_NOATIME | S_NOQUOTA); | |
1401 | truncate_inode_pages(&toputinode[cnt]->i_data, 0); | |
1b1dcc1b | 1402 | mutex_unlock(&toputinode[cnt]->i_mutex); |
1da177e4 LT |
1403 | mark_inode_dirty(toputinode[cnt]); |
1404 | iput(toputinode[cnt]); | |
1405 | } | |
d3be915f | 1406 | mutex_unlock(&dqopt->dqonoff_mutex); |
1da177e4 LT |
1407 | } |
1408 | if (sb->s_bdev) | |
1409 | invalidate_bdev(sb->s_bdev, 0); | |
1410 | return 0; | |
1411 | } | |
1412 | ||
1413 | /* | |
1414 | * Turn quotas on on a device | |
1415 | */ | |
1416 | ||
1417 | /* Helper function when we already have the inode */ | |
1418 | static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) | |
1419 | { | |
1420 | struct quota_format_type *fmt = find_quota_format(format_id); | |
1421 | struct super_block *sb = inode->i_sb; | |
1422 | struct quota_info *dqopt = sb_dqopt(sb); | |
1423 | int error; | |
1424 | int oldflags = -1; | |
1425 | ||
1426 | if (!fmt) | |
1427 | return -ESRCH; | |
1428 | if (!S_ISREG(inode->i_mode)) { | |
1429 | error = -EACCES; | |
1430 | goto out_fmt; | |
1431 | } | |
1432 | if (IS_RDONLY(inode)) { | |
1433 | error = -EROFS; | |
1434 | goto out_fmt; | |
1435 | } | |
1436 | if (!sb->s_op->quota_write || !sb->s_op->quota_read) { | |
1437 | error = -EINVAL; | |
1438 | goto out_fmt; | |
1439 | } | |
1440 | ||
1441 | /* As we bypass the pagecache we must now flush the inode so that | |
1442 | * we see all the changes from userspace... */ | |
1443 | write_inode_now(inode, 1); | |
1444 | /* And now flush the block cache so that kernel sees the changes */ | |
1445 | invalidate_bdev(sb->s_bdev, 0); | |
1b1dcc1b | 1446 | mutex_lock(&inode->i_mutex); |
d3be915f | 1447 | mutex_lock(&dqopt->dqonoff_mutex); |
1da177e4 LT |
1448 | if (sb_has_quota_enabled(sb, type)) { |
1449 | error = -EBUSY; | |
1450 | goto out_lock; | |
1451 | } | |
1452 | /* We don't want quota and atime on quota files (deadlocks possible) | |
1453 | * Also nobody should write to the file - we use special IO operations | |
1454 | * which ignore the immutable bit. */ | |
1455 | down_write(&dqopt->dqptr_sem); | |
1456 | oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | S_NOQUOTA); | |
1457 | inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; | |
1458 | up_write(&dqopt->dqptr_sem); | |
31e7ad6a | 1459 | sb->dq_op->drop(inode); |
1da177e4 LT |
1460 | |
1461 | error = -EIO; | |
1462 | dqopt->files[type] = igrab(inode); | |
1463 | if (!dqopt->files[type]) | |
1464 | goto out_lock; | |
1465 | error = -EINVAL; | |
1466 | if (!fmt->qf_ops->check_quota_file(sb, type)) | |
1467 | goto out_file_init; | |
1468 | ||
1469 | dqopt->ops[type] = fmt->qf_ops; | |
1470 | dqopt->info[type].dqi_format = fmt; | |
1471 | INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); | |
d3be915f | 1472 | mutex_lock(&dqopt->dqio_mutex); |
1da177e4 | 1473 | if ((error = dqopt->ops[type]->read_file_info(sb, type)) < 0) { |
d3be915f | 1474 | mutex_unlock(&dqopt->dqio_mutex); |
1da177e4 LT |
1475 | goto out_file_init; |
1476 | } | |
d3be915f | 1477 | mutex_unlock(&dqopt->dqio_mutex); |
1b1dcc1b | 1478 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
1479 | set_enable_flags(dqopt, type); |
1480 | ||
1481 | add_dquot_ref(sb, type); | |
d3be915f | 1482 | mutex_unlock(&dqopt->dqonoff_mutex); |
1da177e4 LT |
1483 | |
1484 | return 0; | |
1485 | ||
1486 | out_file_init: | |
1487 | dqopt->files[type] = NULL; | |
1488 | iput(inode); | |
1489 | out_lock: | |
d3be915f | 1490 | mutex_unlock(&dqopt->dqonoff_mutex); |
1da177e4 LT |
1491 | if (oldflags != -1) { |
1492 | down_write(&dqopt->dqptr_sem); | |
1493 | /* Set the flags back (in the case of accidental quotaon() | |
1494 | * on a wrong file we don't want to mess up the flags) */ | |
1495 | inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); | |
1496 | inode->i_flags |= oldflags; | |
1497 | up_write(&dqopt->dqptr_sem); | |
1498 | } | |
1b1dcc1b | 1499 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
1500 | out_fmt: |
1501 | put_quota_format(fmt); | |
1502 | ||
1503 | return error; | |
1504 | } | |
1505 | ||
1506 | /* Actual function called from quotactl() */ | |
1507 | int vfs_quota_on(struct super_block *sb, int type, int format_id, char *path) | |
1508 | { | |
1509 | struct nameidata nd; | |
1510 | int error; | |
1511 | ||
1512 | error = path_lookup(path, LOOKUP_FOLLOW, &nd); | |
1513 | if (error < 0) | |
1514 | return error; | |
1515 | error = security_quota_on(nd.dentry); | |
1516 | if (error) | |
1517 | goto out_path; | |
1518 | /* Quota file not on the same filesystem? */ | |
1519 | if (nd.mnt->mnt_sb != sb) | |
1520 | error = -EXDEV; | |
7b7b1ace | 1521 | else |
1da177e4 | 1522 | error = vfs_quota_on_inode(nd.dentry->d_inode, type, format_id); |
1da177e4 LT |
1523 | out_path: |
1524 | path_release(&nd); | |
1525 | return error; | |
1526 | } | |
1527 | ||
1528 | /* | |
1529 | * This function is used when filesystem needs to initialize quotas | |
1530 | * during mount time. | |
1531 | */ | |
84de856e CH |
1532 | int vfs_quota_on_mount(struct super_block *sb, char *qf_name, |
1533 | int format_id, int type) | |
1da177e4 | 1534 | { |
84de856e | 1535 | struct dentry *dentry; |
1da177e4 LT |
1536 | int error; |
1537 | ||
2fa389c5 | 1538 | dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); |
84de856e CH |
1539 | if (IS_ERR(dentry)) |
1540 | return PTR_ERR(dentry); | |
1541 | ||
154f484b JK |
1542 | if (!dentry->d_inode) { |
1543 | error = -ENOENT; | |
1544 | goto out; | |
1545 | } | |
1546 | ||
1da177e4 | 1547 | error = security_quota_on(dentry); |
84de856e CH |
1548 | if (!error) |
1549 | error = vfs_quota_on_inode(dentry->d_inode, type, format_id); | |
1550 | ||
154f484b | 1551 | out: |
84de856e CH |
1552 | dput(dentry); |
1553 | return error; | |
1da177e4 LT |
1554 | } |
1555 | ||
1556 | /* Generic routine for getting common part of quota structure */ | |
1557 | static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di) | |
1558 | { | |
1559 | struct mem_dqblk *dm = &dquot->dq_dqb; | |
1560 | ||
1561 | spin_lock(&dq_data_lock); | |
1562 | di->dqb_bhardlimit = dm->dqb_bhardlimit; | |
1563 | di->dqb_bsoftlimit = dm->dqb_bsoftlimit; | |
1564 | di->dqb_curspace = dm->dqb_curspace; | |
1565 | di->dqb_ihardlimit = dm->dqb_ihardlimit; | |
1566 | di->dqb_isoftlimit = dm->dqb_isoftlimit; | |
1567 | di->dqb_curinodes = dm->dqb_curinodes; | |
1568 | di->dqb_btime = dm->dqb_btime; | |
1569 | di->dqb_itime = dm->dqb_itime; | |
1570 | di->dqb_valid = QIF_ALL; | |
1571 | spin_unlock(&dq_data_lock); | |
1572 | } | |
1573 | ||
1574 | int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di) | |
1575 | { | |
1576 | struct dquot *dquot; | |
1577 | ||
d3be915f | 1578 | mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 | 1579 | if (!(dquot = dqget(sb, id, type))) { |
d3be915f | 1580 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 LT |
1581 | return -ESRCH; |
1582 | } | |
1583 | do_get_dqblk(dquot, di); | |
1584 | dqput(dquot); | |
d3be915f | 1585 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 LT |
1586 | return 0; |
1587 | } | |
1588 | ||
1589 | /* Generic routine for setting common part of quota structure */ | |
1590 | static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di) | |
1591 | { | |
1592 | struct mem_dqblk *dm = &dquot->dq_dqb; | |
1593 | int check_blim = 0, check_ilim = 0; | |
1594 | ||
1595 | spin_lock(&dq_data_lock); | |
1596 | if (di->dqb_valid & QIF_SPACE) { | |
1597 | dm->dqb_curspace = di->dqb_curspace; | |
1598 | check_blim = 1; | |
1599 | } | |
1600 | if (di->dqb_valid & QIF_BLIMITS) { | |
1601 | dm->dqb_bsoftlimit = di->dqb_bsoftlimit; | |
1602 | dm->dqb_bhardlimit = di->dqb_bhardlimit; | |
1603 | check_blim = 1; | |
1604 | } | |
1605 | if (di->dqb_valid & QIF_INODES) { | |
1606 | dm->dqb_curinodes = di->dqb_curinodes; | |
1607 | check_ilim = 1; | |
1608 | } | |
1609 | if (di->dqb_valid & QIF_ILIMITS) { | |
1610 | dm->dqb_isoftlimit = di->dqb_isoftlimit; | |
1611 | dm->dqb_ihardlimit = di->dqb_ihardlimit; | |
1612 | check_ilim = 1; | |
1613 | } | |
1614 | if (di->dqb_valid & QIF_BTIME) | |
1615 | dm->dqb_btime = di->dqb_btime; | |
1616 | if (di->dqb_valid & QIF_ITIME) | |
1617 | dm->dqb_itime = di->dqb_itime; | |
1618 | ||
1619 | if (check_blim) { | |
1620 | if (!dm->dqb_bsoftlimit || toqb(dm->dqb_curspace) < dm->dqb_bsoftlimit) { | |
1621 | dm->dqb_btime = 0; | |
1622 | clear_bit(DQ_BLKS_B, &dquot->dq_flags); | |
1623 | } | |
1624 | else if (!(di->dqb_valid & QIF_BTIME)) /* Set grace only if user hasn't provided his own... */ | |
1625 | dm->dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace; | |
1626 | } | |
1627 | if (check_ilim) { | |
1628 | if (!dm->dqb_isoftlimit || dm->dqb_curinodes < dm->dqb_isoftlimit) { | |
1629 | dm->dqb_itime = 0; | |
1630 | clear_bit(DQ_INODES_B, &dquot->dq_flags); | |
1631 | } | |
1632 | else if (!(di->dqb_valid & QIF_ITIME)) /* Set grace only if user hasn't provided his own... */ | |
1633 | dm->dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; | |
1634 | } | |
1635 | if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || dm->dqb_isoftlimit) | |
1636 | clear_bit(DQ_FAKE_B, &dquot->dq_flags); | |
1637 | else | |
1638 | set_bit(DQ_FAKE_B, &dquot->dq_flags); | |
1639 | spin_unlock(&dq_data_lock); | |
1640 | mark_dquot_dirty(dquot); | |
1641 | } | |
1642 | ||
1643 | int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di) | |
1644 | { | |
1645 | struct dquot *dquot; | |
1646 | ||
d3be915f | 1647 | mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 | 1648 | if (!(dquot = dqget(sb, id, type))) { |
d3be915f | 1649 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 LT |
1650 | return -ESRCH; |
1651 | } | |
1652 | do_set_dqblk(dquot, di); | |
1653 | dqput(dquot); | |
d3be915f | 1654 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 LT |
1655 | return 0; |
1656 | } | |
1657 | ||
1658 | /* Generic routine for getting common part of quota file information */ | |
1659 | int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) | |
1660 | { | |
1661 | struct mem_dqinfo *mi; | |
1662 | ||
d3be915f | 1663 | mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 | 1664 | if (!sb_has_quota_enabled(sb, type)) { |
d3be915f | 1665 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 LT |
1666 | return -ESRCH; |
1667 | } | |
1668 | mi = sb_dqopt(sb)->info + type; | |
1669 | spin_lock(&dq_data_lock); | |
1670 | ii->dqi_bgrace = mi->dqi_bgrace; | |
1671 | ii->dqi_igrace = mi->dqi_igrace; | |
1672 | ii->dqi_flags = mi->dqi_flags & DQF_MASK; | |
1673 | ii->dqi_valid = IIF_ALL; | |
1674 | spin_unlock(&dq_data_lock); | |
d3be915f | 1675 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 LT |
1676 | return 0; |
1677 | } | |
1678 | ||
1679 | /* Generic routine for setting common part of quota file information */ | |
1680 | int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) | |
1681 | { | |
1682 | struct mem_dqinfo *mi; | |
1683 | ||
d3be915f | 1684 | mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 | 1685 | if (!sb_has_quota_enabled(sb, type)) { |
d3be915f | 1686 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 LT |
1687 | return -ESRCH; |
1688 | } | |
1689 | mi = sb_dqopt(sb)->info + type; | |
1690 | spin_lock(&dq_data_lock); | |
1691 | if (ii->dqi_valid & IIF_BGRACE) | |
1692 | mi->dqi_bgrace = ii->dqi_bgrace; | |
1693 | if (ii->dqi_valid & IIF_IGRACE) | |
1694 | mi->dqi_igrace = ii->dqi_igrace; | |
1695 | if (ii->dqi_valid & IIF_FLAGS) | |
1696 | mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | (ii->dqi_flags & DQF_MASK); | |
1697 | spin_unlock(&dq_data_lock); | |
1698 | mark_info_dirty(sb, type); | |
1699 | /* Force write to disk */ | |
1700 | sb->dq_op->write_info(sb, type); | |
d3be915f | 1701 | mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); |
1da177e4 LT |
1702 | return 0; |
1703 | } | |
1704 | ||
1705 | struct quotactl_ops vfs_quotactl_ops = { | |
1706 | .quota_on = vfs_quota_on, | |
1707 | .quota_off = vfs_quota_off, | |
1708 | .quota_sync = vfs_quota_sync, | |
1709 | .get_info = vfs_get_dqinfo, | |
1710 | .set_info = vfs_set_dqinfo, | |
1711 | .get_dqblk = vfs_get_dqblk, | |
1712 | .set_dqblk = vfs_set_dqblk | |
1713 | }; | |
1714 | ||
1715 | static ctl_table fs_dqstats_table[] = { | |
1716 | { | |
1717 | .ctl_name = FS_DQ_LOOKUPS, | |
1718 | .procname = "lookups", | |
1719 | .data = &dqstats.lookups, | |
1720 | .maxlen = sizeof(int), | |
1721 | .mode = 0444, | |
1722 | .proc_handler = &proc_dointvec, | |
1723 | }, | |
1724 | { | |
1725 | .ctl_name = FS_DQ_DROPS, | |
1726 | .procname = "drops", | |
1727 | .data = &dqstats.drops, | |
1728 | .maxlen = sizeof(int), | |
1729 | .mode = 0444, | |
1730 | .proc_handler = &proc_dointvec, | |
1731 | }, | |
1732 | { | |
1733 | .ctl_name = FS_DQ_READS, | |
1734 | .procname = "reads", | |
1735 | .data = &dqstats.reads, | |
1736 | .maxlen = sizeof(int), | |
1737 | .mode = 0444, | |
1738 | .proc_handler = &proc_dointvec, | |
1739 | }, | |
1740 | { | |
1741 | .ctl_name = FS_DQ_WRITES, | |
1742 | .procname = "writes", | |
1743 | .data = &dqstats.writes, | |
1744 | .maxlen = sizeof(int), | |
1745 | .mode = 0444, | |
1746 | .proc_handler = &proc_dointvec, | |
1747 | }, | |
1748 | { | |
1749 | .ctl_name = FS_DQ_CACHE_HITS, | |
1750 | .procname = "cache_hits", | |
1751 | .data = &dqstats.cache_hits, | |
1752 | .maxlen = sizeof(int), | |
1753 | .mode = 0444, | |
1754 | .proc_handler = &proc_dointvec, | |
1755 | }, | |
1756 | { | |
1757 | .ctl_name = FS_DQ_ALLOCATED, | |
1758 | .procname = "allocated_dquots", | |
1759 | .data = &dqstats.allocated_dquots, | |
1760 | .maxlen = sizeof(int), | |
1761 | .mode = 0444, | |
1762 | .proc_handler = &proc_dointvec, | |
1763 | }, | |
1764 | { | |
1765 | .ctl_name = FS_DQ_FREE, | |
1766 | .procname = "free_dquots", | |
1767 | .data = &dqstats.free_dquots, | |
1768 | .maxlen = sizeof(int), | |
1769 | .mode = 0444, | |
1770 | .proc_handler = &proc_dointvec, | |
1771 | }, | |
1772 | { | |
1773 | .ctl_name = FS_DQ_SYNCS, | |
1774 | .procname = "syncs", | |
1775 | .data = &dqstats.syncs, | |
1776 | .maxlen = sizeof(int), | |
1777 | .mode = 0444, | |
1778 | .proc_handler = &proc_dointvec, | |
1779 | }, | |
1780 | { | |
1781 | .ctl_name = FS_DQ_WARNINGS, | |
1782 | .procname = "warnings", | |
1783 | .data = &flag_print_warnings, | |
1784 | .maxlen = sizeof(int), | |
1785 | .mode = 0644, | |
1786 | .proc_handler = &proc_dointvec, | |
1787 | }, | |
1788 | { .ctl_name = 0 }, | |
1789 | }; | |
1790 | ||
1791 | static ctl_table fs_table[] = { | |
1792 | { | |
1793 | .ctl_name = FS_DQSTATS, | |
1794 | .procname = "quota", | |
1795 | .mode = 0555, | |
1796 | .child = fs_dqstats_table, | |
1797 | }, | |
1798 | { .ctl_name = 0 }, | |
1799 | }; | |
1800 | ||
1801 | static ctl_table sys_table[] = { | |
1802 | { | |
1803 | .ctl_name = CTL_FS, | |
1804 | .procname = "fs", | |
1805 | .mode = 0555, | |
1806 | .child = fs_table, | |
1807 | }, | |
1808 | { .ctl_name = 0 }, | |
1809 | }; | |
1810 | ||
1811 | static int __init dquot_init(void) | |
1812 | { | |
1813 | int i; | |
1814 | unsigned long nr_hash, order; | |
1815 | ||
1816 | printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); | |
1817 | ||
1818 | register_sysctl_table(sys_table, 0); | |
1819 | ||
1820 | dquot_cachep = kmem_cache_create("dquot", | |
1821 | sizeof(struct dquot), sizeof(unsigned long) * 4, | |
fffb60f9 PJ |
1822 | (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| |
1823 | SLAB_MEM_SPREAD|SLAB_PANIC), | |
1da177e4 LT |
1824 | NULL, NULL); |
1825 | ||
1826 | order = 0; | |
1827 | dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); | |
1828 | if (!dquot_hash) | |
1829 | panic("Cannot create dquot hash table"); | |
1830 | ||
1831 | /* Find power-of-two hlist_heads which can fit into allocation */ | |
1832 | nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); | |
1833 | dq_hash_bits = 0; | |
1834 | do { | |
1835 | dq_hash_bits++; | |
1836 | } while (nr_hash >> dq_hash_bits); | |
1837 | dq_hash_bits--; | |
1838 | ||
1839 | nr_hash = 1UL << dq_hash_bits; | |
1840 | dq_hash_mask = nr_hash - 1; | |
1841 | for (i = 0; i < nr_hash; i++) | |
1842 | INIT_HLIST_HEAD(dquot_hash + i); | |
1843 | ||
1844 | printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", | |
1845 | nr_hash, order, (PAGE_SIZE << order)); | |
1846 | ||
1847 | set_shrinker(DEFAULT_SEEKS, shrink_dqcache_memory); | |
1848 | ||
1849 | return 0; | |
1850 | } | |
1851 | module_init(dquot_init); | |
1852 | ||
1853 | EXPORT_SYMBOL(register_quota_format); | |
1854 | EXPORT_SYMBOL(unregister_quota_format); | |
1855 | EXPORT_SYMBOL(dqstats); | |
1856 | EXPORT_SYMBOL(dq_data_lock); | |
1857 | EXPORT_SYMBOL(vfs_quota_on); | |
1858 | EXPORT_SYMBOL(vfs_quota_on_mount); | |
1859 | EXPORT_SYMBOL(vfs_quota_off); | |
1860 | EXPORT_SYMBOL(vfs_quota_sync); | |
1861 | EXPORT_SYMBOL(vfs_get_dqinfo); | |
1862 | EXPORT_SYMBOL(vfs_set_dqinfo); | |
1863 | EXPORT_SYMBOL(vfs_get_dqblk); | |
1864 | EXPORT_SYMBOL(vfs_set_dqblk); | |
1865 | EXPORT_SYMBOL(dquot_commit); | |
1866 | EXPORT_SYMBOL(dquot_commit_info); | |
1867 | EXPORT_SYMBOL(dquot_acquire); | |
1868 | EXPORT_SYMBOL(dquot_release); | |
1869 | EXPORT_SYMBOL(dquot_mark_dquot_dirty); | |
1870 | EXPORT_SYMBOL(dquot_initialize); | |
1871 | EXPORT_SYMBOL(dquot_drop); | |
1872 | EXPORT_SYMBOL(dquot_alloc_space); | |
1873 | EXPORT_SYMBOL(dquot_alloc_inode); | |
1874 | EXPORT_SYMBOL(dquot_free_space); | |
1875 | EXPORT_SYMBOL(dquot_free_inode); | |
1876 | EXPORT_SYMBOL(dquot_transfer); |