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