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 int reserved = 0; 878 879 spin_lock(&inode_lock); 880 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 881 if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE|I_NEW)) 882 continue; 883 if (unlikely(inode_get_rsv_space(inode) > 0)) 884 reserved = 1; 885 if (!atomic_read(&inode->i_writecount)) 886 continue; 887 if (!dqinit_needed(inode, type)) 888 continue; 889 890 __iget(inode); 891 spin_unlock(&inode_lock); 892 893 iput(old_inode); 894 __dquot_initialize(inode, type); 895 /* We hold a reference to 'inode' so it couldn't have been 896 * removed from s_inodes list while we dropped the inode_lock. 897 * We cannot iput the inode now as we can be holding the last 898 * reference and we cannot iput it under inode_lock. So we 899 * keep the reference and iput it later. */ 900 old_inode = inode; 901 spin_lock(&inode_lock); 902 } 903 spin_unlock(&inode_lock); 904 iput(old_inode); 905 906 if (reserved) { 907 printk(KERN_WARNING "VFS (%s): Writes happened before quota" 908 " was turned on thus quota information is probably " 909 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 910 } 911 } 912 913 /* 914 * Return 0 if dqput() won't block. 915 * (note that 1 doesn't necessarily mean blocking) 916 */ 917 static inline int dqput_blocks(struct dquot *dquot) 918 { 919 if (atomic_read(&dquot->dq_count) <= 1) 920 return 1; 921 return 0; 922 } 923 924 /* 925 * Remove references to dquots from inode and add dquot to list for freeing 926 * if we have the last referece to dquot 927 * We can't race with anybody because we hold dqptr_sem for writing... 928 */ 929 static int remove_inode_dquot_ref(struct inode *inode, int type, 930 struct list_head *tofree_head) 931 { 932 struct dquot *dquot = inode->i_dquot[type]; 933 934 inode->i_dquot[type] = NULL; 935 if (dquot) { 936 if (dqput_blocks(dquot)) { 937 #ifdef __DQUOT_PARANOIA 938 if (atomic_read(&dquot->dq_count) != 1) 939 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count)); 940 #endif 941 spin_lock(&dq_list_lock); 942 /* As dquot must have currently users it can't be on 943 * the free list... */ 944 list_add(&dquot->dq_free, tofree_head); 945 spin_unlock(&dq_list_lock); 946 return 1; 947 } 948 else 949 dqput(dquot); /* We have guaranteed we won't block */ 950 } 951 return 0; 952 } 953 954 /* 955 * Free list of dquots 956 * Dquots are removed from inodes and no new references can be got so we are 957 * the only ones holding reference 958 */ 959 static void put_dquot_list(struct list_head *tofree_head) 960 { 961 struct list_head *act_head; 962 struct dquot *dquot; 963 964 act_head = tofree_head->next; 965 while (act_head != tofree_head) { 966 dquot = list_entry(act_head, struct dquot, dq_free); 967 act_head = act_head->next; 968 /* Remove dquot from the list so we won't have problems... */ 969 list_del_init(&dquot->dq_free); 970 dqput(dquot); 971 } 972 } 973 974 static void remove_dquot_ref(struct super_block *sb, int type, 975 struct list_head *tofree_head) 976 { 977 struct inode *inode; 978 979 spin_lock(&inode_lock); 980 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 981 /* 982 * We have to scan also I_NEW inodes because they can already 983 * have quota pointer initialized. Luckily, we need to touch 984 * only quota pointers and these have separate locking 985 * (dqptr_sem). 986 */ 987 if (!IS_NOQUOTA(inode)) 988 remove_inode_dquot_ref(inode, type, tofree_head); 989 } 990 spin_unlock(&inode_lock); 991 } 992 993 /* Gather all references from inodes and drop them */ 994 static void drop_dquot_ref(struct super_block *sb, int type) 995 { 996 LIST_HEAD(tofree_head); 997 998 if (sb->dq_op) { 999 down_write(&sb_dqopt(sb)->dqptr_sem); 1000 remove_dquot_ref(sb, type, &tofree_head); 1001 up_write(&sb_dqopt(sb)->dqptr_sem); 1002 put_dquot_list(&tofree_head); 1003 } 1004 } 1005 1006 static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1007 { 1008 dquot->dq_dqb.dqb_curinodes += number; 1009 } 1010 1011 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1012 { 1013 dquot->dq_dqb.dqb_curspace += number; 1014 } 1015 1016 static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1017 { 1018 dquot->dq_dqb.dqb_rsvspace += number; 1019 } 1020 1021 /* 1022 * Claim reserved quota space 1023 */ 1024 static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1025 { 1026 if (dquot->dq_dqb.dqb_rsvspace < number) { 1027 WARN_ON_ONCE(1); 1028 number = dquot->dq_dqb.dqb_rsvspace; 1029 } 1030 dquot->dq_dqb.dqb_curspace += number; 1031 dquot->dq_dqb.dqb_rsvspace -= number; 1032 } 1033 1034 static inline 1035 void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1036 { 1037 if (dquot->dq_dqb.dqb_rsvspace >= number) 1038 dquot->dq_dqb.dqb_rsvspace -= number; 1039 else { 1040 WARN_ON_ONCE(1); 1041 dquot->dq_dqb.dqb_rsvspace = 0; 1042 } 1043 } 1044 1045 static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1046 { 1047 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1048 dquot->dq_dqb.dqb_curinodes >= number) 1049 dquot->dq_dqb.dqb_curinodes -= number; 1050 else 1051 dquot->dq_dqb.dqb_curinodes = 0; 1052 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1053 dquot->dq_dqb.dqb_itime = (time_t) 0; 1054 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1055 } 1056 1057 static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1058 { 1059 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1060 dquot->dq_dqb.dqb_curspace >= number) 1061 dquot->dq_dqb.dqb_curspace -= number; 1062 else 1063 dquot->dq_dqb.dqb_curspace = 0; 1064 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1065 dquot->dq_dqb.dqb_btime = (time_t) 0; 1066 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1067 } 1068 1069 static int warning_issued(struct dquot *dquot, const int warntype) 1070 { 1071 int flag = (warntype == QUOTA_NL_BHARDWARN || 1072 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1073 ((warntype == QUOTA_NL_IHARDWARN || 1074 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1075 1076 if (!flag) 1077 return 0; 1078 return test_and_set_bit(flag, &dquot->dq_flags); 1079 } 1080 1081 #ifdef CONFIG_PRINT_QUOTA_WARNING 1082 static int flag_print_warnings = 1; 1083 1084 static int need_print_warning(struct dquot *dquot) 1085 { 1086 if (!flag_print_warnings) 1087 return 0; 1088 1089 switch (dquot->dq_type) { 1090 case USRQUOTA: 1091 return current_fsuid() == dquot->dq_id; 1092 case GRPQUOTA: 1093 return in_group_p(dquot->dq_id); 1094 } 1095 return 0; 1096 } 1097 1098 /* Print warning to user which exceeded quota */ 1099 static void print_warning(struct dquot *dquot, const int warntype) 1100 { 1101 char *msg = NULL; 1102 struct tty_struct *tty; 1103 1104 if (warntype == QUOTA_NL_IHARDBELOW || 1105 warntype == QUOTA_NL_ISOFTBELOW || 1106 warntype == QUOTA_NL_BHARDBELOW || 1107 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot)) 1108 return; 1109 1110 tty = get_current_tty(); 1111 if (!tty) 1112 return; 1113 tty_write_message(tty, dquot->dq_sb->s_id); 1114 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1115 tty_write_message(tty, ": warning, "); 1116 else 1117 tty_write_message(tty, ": write failed, "); 1118 tty_write_message(tty, quotatypes[dquot->dq_type]); 1119 switch (warntype) { 1120 case QUOTA_NL_IHARDWARN: 1121 msg = " file limit reached.\r\n"; 1122 break; 1123 case QUOTA_NL_ISOFTLONGWARN: 1124 msg = " file quota exceeded too long.\r\n"; 1125 break; 1126 case QUOTA_NL_ISOFTWARN: 1127 msg = " file quota exceeded.\r\n"; 1128 break; 1129 case QUOTA_NL_BHARDWARN: 1130 msg = " block limit reached.\r\n"; 1131 break; 1132 case QUOTA_NL_BSOFTLONGWARN: 1133 msg = " block quota exceeded too long.\r\n"; 1134 break; 1135 case QUOTA_NL_BSOFTWARN: 1136 msg = " block quota exceeded.\r\n"; 1137 break; 1138 } 1139 tty_write_message(tty, msg); 1140 tty_kref_put(tty); 1141 } 1142 #endif 1143 1144 /* 1145 * Write warnings to the console and send warning messages over netlink. 1146 * 1147 * Note that this function can sleep. 1148 */ 1149 static void flush_warnings(struct dquot *const *dquots, char *warntype) 1150 { 1151 struct dquot *dq; 1152 int i; 1153 1154 for (i = 0; i < MAXQUOTAS; i++) { 1155 dq = dquots[i]; 1156 if (dq && warntype[i] != QUOTA_NL_NOWARN && 1157 !warning_issued(dq, warntype[i])) { 1158 #ifdef CONFIG_PRINT_QUOTA_WARNING 1159 print_warning(dq, warntype[i]); 1160 #endif 1161 quota_send_warning(dq->dq_type, dq->dq_id, 1162 dq->dq_sb->s_dev, warntype[i]); 1163 } 1164 } 1165 } 1166 1167 static int ignore_hardlimit(struct dquot *dquot) 1168 { 1169 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 1170 1171 return capable(CAP_SYS_RESOURCE) && 1172 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1173 !(info->dqi_flags & V1_DQF_RSQUASH)); 1174 } 1175 1176 /* needs dq_data_lock */ 1177 static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) 1178 { 1179 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1180 1181 *warntype = QUOTA_NL_NOWARN; 1182 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || 1183 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1184 return 0; 1185 1186 if (dquot->dq_dqb.dqb_ihardlimit && 1187 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1188 !ignore_hardlimit(dquot)) { 1189 *warntype = QUOTA_NL_IHARDWARN; 1190 return -EDQUOT; 1191 } 1192 1193 if (dquot->dq_dqb.dqb_isoftlimit && 1194 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1195 dquot->dq_dqb.dqb_itime && 1196 get_seconds() >= dquot->dq_dqb.dqb_itime && 1197 !ignore_hardlimit(dquot)) { 1198 *warntype = QUOTA_NL_ISOFTLONGWARN; 1199 return -EDQUOT; 1200 } 1201 1202 if (dquot->dq_dqb.dqb_isoftlimit && 1203 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1204 dquot->dq_dqb.dqb_itime == 0) { 1205 *warntype = QUOTA_NL_ISOFTWARN; 1206 dquot->dq_dqb.dqb_itime = get_seconds() + 1207 sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; 1208 } 1209 1210 return 0; 1211 } 1212 1213 /* needs dq_data_lock */ 1214 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) 1215 { 1216 qsize_t tspace; 1217 struct super_block *sb = dquot->dq_sb; 1218 1219 *warntype = QUOTA_NL_NOWARN; 1220 if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) || 1221 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1222 return 0; 1223 1224 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1225 + space; 1226 1227 if (dquot->dq_dqb.dqb_bhardlimit && 1228 tspace > dquot->dq_dqb.dqb_bhardlimit && 1229 !ignore_hardlimit(dquot)) { 1230 if (!prealloc) 1231 *warntype = QUOTA_NL_BHARDWARN; 1232 return -EDQUOT; 1233 } 1234 1235 if (dquot->dq_dqb.dqb_bsoftlimit && 1236 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1237 dquot->dq_dqb.dqb_btime && 1238 get_seconds() >= dquot->dq_dqb.dqb_btime && 1239 !ignore_hardlimit(dquot)) { 1240 if (!prealloc) 1241 *warntype = QUOTA_NL_BSOFTLONGWARN; 1242 return -EDQUOT; 1243 } 1244 1245 if (dquot->dq_dqb.dqb_bsoftlimit && 1246 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1247 dquot->dq_dqb.dqb_btime == 0) { 1248 if (!prealloc) { 1249 *warntype = QUOTA_NL_BSOFTWARN; 1250 dquot->dq_dqb.dqb_btime = get_seconds() + 1251 sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace; 1252 } 1253 else 1254 /* 1255 * We don't allow preallocation to exceed softlimit so exceeding will 1256 * be always printed 1257 */ 1258 return -EDQUOT; 1259 } 1260 1261 return 0; 1262 } 1263 1264 static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1265 { 1266 qsize_t newinodes; 1267 1268 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1269 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1270 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type)) 1271 return QUOTA_NL_NOWARN; 1272 1273 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1274 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1275 return QUOTA_NL_ISOFTBELOW; 1276 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1277 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1278 return QUOTA_NL_IHARDBELOW; 1279 return QUOTA_NL_NOWARN; 1280 } 1281 1282 static int info_bdq_free(struct dquot *dquot, qsize_t space) 1283 { 1284 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1285 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1286 return QUOTA_NL_NOWARN; 1287 1288 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1289 return QUOTA_NL_BSOFTBELOW; 1290 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1291 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1292 return QUOTA_NL_BHARDBELOW; 1293 return QUOTA_NL_NOWARN; 1294 } 1295 1296 /* 1297 * Initialize quota pointers in inode 1298 * 1299 * We do things in a bit complicated way but by that we avoid calling 1300 * dqget() and thus filesystem callbacks under dqptr_sem. 1301 * 1302 * It is better to call this function outside of any transaction as it 1303 * might need a lot of space in journal for dquot structure allocation. 1304 */ 1305 static void __dquot_initialize(struct inode *inode, int type) 1306 { 1307 unsigned int id = 0; 1308 int cnt; 1309 struct dquot *got[MAXQUOTAS]; 1310 struct super_block *sb = inode->i_sb; 1311 qsize_t rsv; 1312 1313 /* First test before acquiring mutex - solves deadlocks when we 1314 * re-enter the quota code and are already holding the mutex */ 1315 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1316 return; 1317 1318 /* First get references to structures we might need. */ 1319 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1320 got[cnt] = NULL; 1321 if (type != -1 && cnt != type) 1322 continue; 1323 switch (cnt) { 1324 case USRQUOTA: 1325 id = inode->i_uid; 1326 break; 1327 case GRPQUOTA: 1328 id = inode->i_gid; 1329 break; 1330 } 1331 got[cnt] = dqget(sb, id, cnt); 1332 } 1333 1334 down_write(&sb_dqopt(sb)->dqptr_sem); 1335 if (IS_NOQUOTA(inode)) 1336 goto out_err; 1337 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1338 if (type != -1 && cnt != type) 1339 continue; 1340 /* Avoid races with quotaoff() */ 1341 if (!sb_has_quota_active(sb, cnt)) 1342 continue; 1343 if (!inode->i_dquot[cnt]) { 1344 inode->i_dquot[cnt] = got[cnt]; 1345 got[cnt] = NULL; 1346 /* 1347 * Make quota reservation system happy if someone 1348 * did a write before quota was turned on 1349 */ 1350 rsv = inode_get_rsv_space(inode); 1351 if (unlikely(rsv)) 1352 dquot_resv_space(inode->i_dquot[cnt], rsv); 1353 } 1354 } 1355 out_err: 1356 up_write(&sb_dqopt(sb)->dqptr_sem); 1357 /* Drop unused references */ 1358 dqput_all(got); 1359 } 1360 1361 void dquot_initialize(struct inode *inode) 1362 { 1363 __dquot_initialize(inode, -1); 1364 } 1365 EXPORT_SYMBOL(dquot_initialize); 1366 1367 /* 1368 * Release all quotas referenced by inode 1369 */ 1370 static void __dquot_drop(struct inode *inode) 1371 { 1372 int cnt; 1373 struct dquot *put[MAXQUOTAS]; 1374 1375 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1376 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1377 put[cnt] = inode->i_dquot[cnt]; 1378 inode->i_dquot[cnt] = NULL; 1379 } 1380 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1381 dqput_all(put); 1382 } 1383 1384 void dquot_drop(struct inode *inode) 1385 { 1386 int cnt; 1387 1388 if (IS_NOQUOTA(inode)) 1389 return; 1390 1391 /* 1392 * Test before calling to rule out calls from proc and such 1393 * where we are not allowed to block. Note that this is 1394 * actually reliable test even without the lock - the caller 1395 * must assure that nobody can come after the DQUOT_DROP and 1396 * add quota pointers back anyway. 1397 */ 1398 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1399 if (inode->i_dquot[cnt]) 1400 break; 1401 } 1402 1403 if (cnt < MAXQUOTAS) 1404 __dquot_drop(inode); 1405 } 1406 EXPORT_SYMBOL(dquot_drop); 1407 1408 /* 1409 * inode_reserved_space is managed internally by quota, and protected by 1410 * i_lock similar to i_blocks+i_bytes. 1411 */ 1412 static qsize_t *inode_reserved_space(struct inode * inode) 1413 { 1414 /* Filesystem must explicitly define it's own method in order to use 1415 * quota reservation interface */ 1416 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1417 return inode->i_sb->dq_op->get_reserved_space(inode); 1418 } 1419 1420 void inode_add_rsv_space(struct inode *inode, qsize_t number) 1421 { 1422 spin_lock(&inode->i_lock); 1423 *inode_reserved_space(inode) += number; 1424 spin_unlock(&inode->i_lock); 1425 } 1426 EXPORT_SYMBOL(inode_add_rsv_space); 1427 1428 void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1429 { 1430 spin_lock(&inode->i_lock); 1431 *inode_reserved_space(inode) -= number; 1432 __inode_add_bytes(inode, number); 1433 spin_unlock(&inode->i_lock); 1434 } 1435 EXPORT_SYMBOL(inode_claim_rsv_space); 1436 1437 void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1438 { 1439 spin_lock(&inode->i_lock); 1440 *inode_reserved_space(inode) -= number; 1441 spin_unlock(&inode->i_lock); 1442 } 1443 EXPORT_SYMBOL(inode_sub_rsv_space); 1444 1445 static qsize_t inode_get_rsv_space(struct inode *inode) 1446 { 1447 qsize_t ret; 1448 1449 if (!inode->i_sb->dq_op->get_reserved_space) 1450 return 0; 1451 spin_lock(&inode->i_lock); 1452 ret = *inode_reserved_space(inode); 1453 spin_unlock(&inode->i_lock); 1454 return ret; 1455 } 1456 1457 static void inode_incr_space(struct inode *inode, qsize_t number, 1458 int reserve) 1459 { 1460 if (reserve) 1461 inode_add_rsv_space(inode, number); 1462 else 1463 inode_add_bytes(inode, number); 1464 } 1465 1466 static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1467 { 1468 if (reserve) 1469 inode_sub_rsv_space(inode, number); 1470 else 1471 inode_sub_bytes(inode, number); 1472 } 1473 1474 /* 1475 * This functions updates i_blocks+i_bytes fields and quota information 1476 * (together with appropriate checks). 1477 * 1478 * NOTE: We absolutely rely on the fact that caller dirties the inode 1479 * (usually helpers in quotaops.h care about this) and holds a handle for 1480 * the current transaction so that dquot write and inode write go into the 1481 * same transaction. 1482 */ 1483 1484 /* 1485 * This operation can block, but only after everything is updated 1486 */ 1487 int __dquot_alloc_space(struct inode *inode, qsize_t number, 1488 int warn, int reserve) 1489 { 1490 int cnt, ret = 0; 1491 char warntype[MAXQUOTAS]; 1492 1493 /* 1494 * First test before acquiring mutex - solves deadlocks when we 1495 * re-enter the quota code and are already holding the mutex 1496 */ 1497 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1498 inode_incr_space(inode, number, reserve); 1499 goto out; 1500 } 1501 1502 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1503 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1504 warntype[cnt] = QUOTA_NL_NOWARN; 1505 1506 spin_lock(&dq_data_lock); 1507 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1508 if (!inode->i_dquot[cnt]) 1509 continue; 1510 ret = check_bdq(inode->i_dquot[cnt], number, !warn, 1511 warntype+cnt); 1512 if (ret) { 1513 spin_unlock(&dq_data_lock); 1514 goto out_flush_warn; 1515 } 1516 } 1517 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1518 if (!inode->i_dquot[cnt]) 1519 continue; 1520 if (reserve) 1521 dquot_resv_space(inode->i_dquot[cnt], number); 1522 else 1523 dquot_incr_space(inode->i_dquot[cnt], number); 1524 } 1525 inode_incr_space(inode, number, reserve); 1526 spin_unlock(&dq_data_lock); 1527 1528 if (reserve) 1529 goto out_flush_warn; 1530 mark_all_dquot_dirty(inode->i_dquot); 1531 out_flush_warn: 1532 flush_warnings(inode->i_dquot, warntype); 1533 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1534 out: 1535 return ret; 1536 } 1537 EXPORT_SYMBOL(__dquot_alloc_space); 1538 1539 /* 1540 * This operation can block, but only after everything is updated 1541 */ 1542 int dquot_alloc_inode(const struct inode *inode) 1543 { 1544 int cnt, ret = 0; 1545 char warntype[MAXQUOTAS]; 1546 1547 /* First test before acquiring mutex - solves deadlocks when we 1548 * re-enter the quota code and are already holding the mutex */ 1549 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1550 return 0; 1551 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1552 warntype[cnt] = QUOTA_NL_NOWARN; 1553 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1554 spin_lock(&dq_data_lock); 1555 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1556 if (!inode->i_dquot[cnt]) 1557 continue; 1558 ret = check_idq(inode->i_dquot[cnt], 1, warntype + cnt); 1559 if (ret) 1560 goto warn_put_all; 1561 } 1562 1563 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1564 if (!inode->i_dquot[cnt]) 1565 continue; 1566 dquot_incr_inodes(inode->i_dquot[cnt], 1); 1567 } 1568 1569 warn_put_all: 1570 spin_unlock(&dq_data_lock); 1571 if (ret == 0) 1572 mark_all_dquot_dirty(inode->i_dquot); 1573 flush_warnings(inode->i_dquot, warntype); 1574 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1575 return ret; 1576 } 1577 EXPORT_SYMBOL(dquot_alloc_inode); 1578 1579 /* 1580 * Convert in-memory reserved quotas to real consumed quotas 1581 */ 1582 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1583 { 1584 int cnt; 1585 1586 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1587 inode_claim_rsv_space(inode, number); 1588 return 0; 1589 } 1590 1591 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1592 spin_lock(&dq_data_lock); 1593 /* Claim reserved quotas to allocated quotas */ 1594 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1595 if (inode->i_dquot[cnt]) 1596 dquot_claim_reserved_space(inode->i_dquot[cnt], 1597 number); 1598 } 1599 /* Update inode bytes */ 1600 inode_claim_rsv_space(inode, number); 1601 spin_unlock(&dq_data_lock); 1602 mark_all_dquot_dirty(inode->i_dquot); 1603 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1604 return 0; 1605 } 1606 EXPORT_SYMBOL(dquot_claim_space_nodirty); 1607 1608 /* 1609 * This operation can block, but only after everything is updated 1610 */ 1611 void __dquot_free_space(struct inode *inode, qsize_t number, int reserve) 1612 { 1613 unsigned int cnt; 1614 char warntype[MAXQUOTAS]; 1615 1616 /* First test before acquiring mutex - solves deadlocks when we 1617 * re-enter the quota code and are already holding the mutex */ 1618 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1619 inode_decr_space(inode, number, reserve); 1620 return; 1621 } 1622 1623 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1624 spin_lock(&dq_data_lock); 1625 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1626 if (!inode->i_dquot[cnt]) 1627 continue; 1628 warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number); 1629 if (reserve) 1630 dquot_free_reserved_space(inode->i_dquot[cnt], number); 1631 else 1632 dquot_decr_space(inode->i_dquot[cnt], number); 1633 } 1634 inode_decr_space(inode, number, reserve); 1635 spin_unlock(&dq_data_lock); 1636 1637 if (reserve) 1638 goto out_unlock; 1639 mark_all_dquot_dirty(inode->i_dquot); 1640 out_unlock: 1641 flush_warnings(inode->i_dquot, warntype); 1642 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1643 } 1644 EXPORT_SYMBOL(__dquot_free_space); 1645 1646 /* 1647 * This operation can block, but only after everything is updated 1648 */ 1649 void dquot_free_inode(const struct inode *inode) 1650 { 1651 unsigned int cnt; 1652 char warntype[MAXQUOTAS]; 1653 1654 /* First test before acquiring mutex - solves deadlocks when we 1655 * re-enter the quota code and are already holding the mutex */ 1656 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1657 return; 1658 1659 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1660 spin_lock(&dq_data_lock); 1661 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1662 if (!inode->i_dquot[cnt]) 1663 continue; 1664 warntype[cnt] = info_idq_free(inode->i_dquot[cnt], 1); 1665 dquot_decr_inodes(inode->i_dquot[cnt], 1); 1666 } 1667 spin_unlock(&dq_data_lock); 1668 mark_all_dquot_dirty(inode->i_dquot); 1669 flush_warnings(inode->i_dquot, warntype); 1670 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1671 } 1672 EXPORT_SYMBOL(dquot_free_inode); 1673 1674 /* 1675 * Transfer the number of inode and blocks from one diskquota to an other. 1676 * 1677 * This operation can block, but only after everything is updated 1678 * A transaction must be started when entering this function. 1679 */ 1680 static int __dquot_transfer(struct inode *inode, qid_t *chid, unsigned long mask) 1681 { 1682 qsize_t space, cur_space; 1683 qsize_t rsv_space = 0; 1684 struct dquot *transfer_from[MAXQUOTAS]; 1685 struct dquot *transfer_to[MAXQUOTAS]; 1686 int cnt, ret = 0; 1687 char warntype_to[MAXQUOTAS]; 1688 char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS]; 1689 1690 /* First test before acquiring mutex - solves deadlocks when we 1691 * re-enter the quota code and are already holding the mutex */ 1692 if (IS_NOQUOTA(inode)) 1693 return 0; 1694 /* Initialize the arrays */ 1695 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1696 transfer_from[cnt] = NULL; 1697 transfer_to[cnt] = NULL; 1698 warntype_to[cnt] = QUOTA_NL_NOWARN; 1699 } 1700 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1701 if (mask & (1 << cnt)) 1702 transfer_to[cnt] = dqget(inode->i_sb, chid[cnt], cnt); 1703 } 1704 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1705 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1706 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1707 goto put_all; 1708 } 1709 spin_lock(&dq_data_lock); 1710 cur_space = inode_get_bytes(inode); 1711 rsv_space = inode_get_rsv_space(inode); 1712 space = cur_space + rsv_space; 1713 /* Build the transfer_from list and check the limits */ 1714 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1715 if (!transfer_to[cnt]) 1716 continue; 1717 transfer_from[cnt] = inode->i_dquot[cnt]; 1718 ret = check_idq(transfer_to[cnt], 1, warntype_to + cnt); 1719 if (ret) 1720 goto over_quota; 1721 ret = check_bdq(transfer_to[cnt], space, 0, warntype_to + cnt); 1722 if (ret) 1723 goto over_quota; 1724 } 1725 1726 /* 1727 * Finally perform the needed transfer from transfer_from to transfer_to 1728 */ 1729 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1730 /* 1731 * Skip changes for same uid or gid or for turned off quota-type. 1732 */ 1733 if (!transfer_to[cnt]) 1734 continue; 1735 1736 /* Due to IO error we might not have transfer_from[] structure */ 1737 if (transfer_from[cnt]) { 1738 warntype_from_inodes[cnt] = 1739 info_idq_free(transfer_from[cnt], 1); 1740 warntype_from_space[cnt] = 1741 info_bdq_free(transfer_from[cnt], space); 1742 dquot_decr_inodes(transfer_from[cnt], 1); 1743 dquot_decr_space(transfer_from[cnt], cur_space); 1744 dquot_free_reserved_space(transfer_from[cnt], 1745 rsv_space); 1746 } 1747 1748 dquot_incr_inodes(transfer_to[cnt], 1); 1749 dquot_incr_space(transfer_to[cnt], cur_space); 1750 dquot_resv_space(transfer_to[cnt], rsv_space); 1751 1752 inode->i_dquot[cnt] = transfer_to[cnt]; 1753 } 1754 spin_unlock(&dq_data_lock); 1755 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1756 1757 mark_all_dquot_dirty(transfer_from); 1758 mark_all_dquot_dirty(transfer_to); 1759 /* The reference we got is transferred to the inode */ 1760 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1761 transfer_to[cnt] = NULL; 1762 warn_put_all: 1763 flush_warnings(transfer_to, warntype_to); 1764 flush_warnings(transfer_from, warntype_from_inodes); 1765 flush_warnings(transfer_from, warntype_from_space); 1766 put_all: 1767 dqput_all(transfer_from); 1768 dqput_all(transfer_to); 1769 return ret; 1770 over_quota: 1771 spin_unlock(&dq_data_lock); 1772 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1773 /* Clear dquot pointers we don't want to dqput() */ 1774 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1775 transfer_from[cnt] = NULL; 1776 goto warn_put_all; 1777 } 1778 1779 /* Wrapper for transferring ownership of an inode for uid/gid only 1780 * Called from FSXXX_setattr() 1781 */ 1782 int dquot_transfer(struct inode *inode, struct iattr *iattr) 1783 { 1784 qid_t chid[MAXQUOTAS]; 1785 unsigned long mask = 0; 1786 1787 if (iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) { 1788 mask |= 1 << USRQUOTA; 1789 chid[USRQUOTA] = iattr->ia_uid; 1790 } 1791 if (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid) { 1792 mask |= 1 << GRPQUOTA; 1793 chid[GRPQUOTA] = iattr->ia_gid; 1794 } 1795 if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) { 1796 dquot_initialize(inode); 1797 return __dquot_transfer(inode, chid, mask); 1798 } 1799 return 0; 1800 } 1801 EXPORT_SYMBOL(dquot_transfer); 1802 1803 /* 1804 * Write info of quota file to disk 1805 */ 1806 int dquot_commit_info(struct super_block *sb, int type) 1807 { 1808 int ret; 1809 struct quota_info *dqopt = sb_dqopt(sb); 1810 1811 mutex_lock(&dqopt->dqio_mutex); 1812 ret = dqopt->ops[type]->write_file_info(sb, type); 1813 mutex_unlock(&dqopt->dqio_mutex); 1814 return ret; 1815 } 1816 EXPORT_SYMBOL(dquot_commit_info); 1817 1818 /* 1819 * Definitions of diskquota operations. 1820 */ 1821 const struct dquot_operations dquot_operations = { 1822 .write_dquot = dquot_commit, 1823 .acquire_dquot = dquot_acquire, 1824 .release_dquot = dquot_release, 1825 .mark_dirty = dquot_mark_dquot_dirty, 1826 .write_info = dquot_commit_info, 1827 .alloc_dquot = dquot_alloc, 1828 .destroy_dquot = dquot_destroy, 1829 }; 1830 1831 /* 1832 * Generic helper for ->open on filesystems supporting disk quotas. 1833 */ 1834 int dquot_file_open(struct inode *inode, struct file *file) 1835 { 1836 int error; 1837 1838 error = generic_file_open(inode, file); 1839 if (!error && (file->f_mode & FMODE_WRITE)) 1840 dquot_initialize(inode); 1841 return error; 1842 } 1843 EXPORT_SYMBOL(dquot_file_open); 1844 1845 /* 1846 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 1847 */ 1848 int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags) 1849 { 1850 int cnt, ret = 0; 1851 struct quota_info *dqopt = sb_dqopt(sb); 1852 struct inode *toputinode[MAXQUOTAS]; 1853 1854 /* Cannot turn off usage accounting without turning off limits, or 1855 * suspend quotas and simultaneously turn quotas off. */ 1856 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 1857 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 1858 DQUOT_USAGE_ENABLED))) 1859 return -EINVAL; 1860 1861 /* We need to serialize quota_off() for device */ 1862 mutex_lock(&dqopt->dqonoff_mutex); 1863 1864 /* 1865 * Skip everything if there's nothing to do. We have to do this because 1866 * sometimes we are called when fill_super() failed and calling 1867 * sync_fs() in such cases does no good. 1868 */ 1869 if (!sb_any_quota_loaded(sb)) { 1870 mutex_unlock(&dqopt->dqonoff_mutex); 1871 return 0; 1872 } 1873 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1874 toputinode[cnt] = NULL; 1875 if (type != -1 && cnt != type) 1876 continue; 1877 if (!sb_has_quota_loaded(sb, cnt)) 1878 continue; 1879 1880 if (flags & DQUOT_SUSPENDED) { 1881 spin_lock(&dq_state_lock); 1882 dqopt->flags |= 1883 dquot_state_flag(DQUOT_SUSPENDED, cnt); 1884 spin_unlock(&dq_state_lock); 1885 } else { 1886 spin_lock(&dq_state_lock); 1887 dqopt->flags &= ~dquot_state_flag(flags, cnt); 1888 /* Turning off suspended quotas? */ 1889 if (!sb_has_quota_loaded(sb, cnt) && 1890 sb_has_quota_suspended(sb, cnt)) { 1891 dqopt->flags &= ~dquot_state_flag( 1892 DQUOT_SUSPENDED, cnt); 1893 spin_unlock(&dq_state_lock); 1894 iput(dqopt->files[cnt]); 1895 dqopt->files[cnt] = NULL; 1896 continue; 1897 } 1898 spin_unlock(&dq_state_lock); 1899 } 1900 1901 /* We still have to keep quota loaded? */ 1902 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 1903 continue; 1904 1905 /* Note: these are blocking operations */ 1906 drop_dquot_ref(sb, cnt); 1907 invalidate_dquots(sb, cnt); 1908 /* 1909 * Now all dquots should be invalidated, all writes done so we 1910 * should be only users of the info. No locks needed. 1911 */ 1912 if (info_dirty(&dqopt->info[cnt])) 1913 sb->dq_op->write_info(sb, cnt); 1914 if (dqopt->ops[cnt]->free_file_info) 1915 dqopt->ops[cnt]->free_file_info(sb, cnt); 1916 put_quota_format(dqopt->info[cnt].dqi_format); 1917 1918 toputinode[cnt] = dqopt->files[cnt]; 1919 if (!sb_has_quota_loaded(sb, cnt)) 1920 dqopt->files[cnt] = NULL; 1921 dqopt->info[cnt].dqi_flags = 0; 1922 dqopt->info[cnt].dqi_igrace = 0; 1923 dqopt->info[cnt].dqi_bgrace = 0; 1924 dqopt->ops[cnt] = NULL; 1925 } 1926 mutex_unlock(&dqopt->dqonoff_mutex); 1927 1928 /* Skip syncing and setting flags if quota files are hidden */ 1929 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 1930 goto put_inodes; 1931 1932 /* Sync the superblock so that buffers with quota data are written to 1933 * disk (and so userspace sees correct data afterwards). */ 1934 if (sb->s_op->sync_fs) 1935 sb->s_op->sync_fs(sb, 1); 1936 sync_blockdev(sb->s_bdev); 1937 /* Now the quota files are just ordinary files and we can set the 1938 * inode flags back. Moreover we discard the pagecache so that 1939 * userspace sees the writes we did bypassing the pagecache. We 1940 * must also discard the blockdev buffers so that we see the 1941 * changes done by userspace on the next quotaon() */ 1942 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1943 if (toputinode[cnt]) { 1944 mutex_lock(&dqopt->dqonoff_mutex); 1945 /* If quota was reenabled in the meantime, we have 1946 * nothing to do */ 1947 if (!sb_has_quota_loaded(sb, cnt)) { 1948 mutex_lock_nested(&toputinode[cnt]->i_mutex, 1949 I_MUTEX_QUOTA); 1950 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 1951 S_NOATIME | S_NOQUOTA); 1952 truncate_inode_pages(&toputinode[cnt]->i_data, 1953 0); 1954 mutex_unlock(&toputinode[cnt]->i_mutex); 1955 mark_inode_dirty(toputinode[cnt]); 1956 } 1957 mutex_unlock(&dqopt->dqonoff_mutex); 1958 } 1959 if (sb->s_bdev) 1960 invalidate_bdev(sb->s_bdev); 1961 put_inodes: 1962 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1963 if (toputinode[cnt]) { 1964 /* On remount RO, we keep the inode pointer so that we 1965 * can reenable quota on the subsequent remount RW. We 1966 * have to check 'flags' variable and not use sb_has_ 1967 * function because another quotaon / quotaoff could 1968 * change global state before we got here. We refuse 1969 * to suspend quotas when there is pending delete on 1970 * the quota file... */ 1971 if (!(flags & DQUOT_SUSPENDED)) 1972 iput(toputinode[cnt]); 1973 else if (!toputinode[cnt]->i_nlink) 1974 ret = -EBUSY; 1975 } 1976 return ret; 1977 } 1978 EXPORT_SYMBOL(vfs_quota_disable); 1979 1980 int vfs_quota_off(struct super_block *sb, int type, int remount) 1981 { 1982 return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED : 1983 (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED)); 1984 } 1985 EXPORT_SYMBOL(vfs_quota_off); 1986 /* 1987 * Turn quotas on on a device 1988 */ 1989 1990 /* 1991 * Helper function to turn quotas on when we already have the inode of 1992 * quota file and no quota information is loaded. 1993 */ 1994 static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 1995 unsigned int flags) 1996 { 1997 struct quota_format_type *fmt = find_quota_format(format_id); 1998 struct super_block *sb = inode->i_sb; 1999 struct quota_info *dqopt = sb_dqopt(sb); 2000 int error; 2001 int oldflags = -1; 2002 2003 if (!fmt) 2004 return -ESRCH; 2005 if (!S_ISREG(inode->i_mode)) { 2006 error = -EACCES; 2007 goto out_fmt; 2008 } 2009 if (IS_RDONLY(inode)) { 2010 error = -EROFS; 2011 goto out_fmt; 2012 } 2013 if (!sb->s_op->quota_write || !sb->s_op->quota_read) { 2014 error = -EINVAL; 2015 goto out_fmt; 2016 } 2017 /* Usage always has to be set... */ 2018 if (!(flags & DQUOT_USAGE_ENABLED)) { 2019 error = -EINVAL; 2020 goto out_fmt; 2021 } 2022 2023 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2024 /* As we bypass the pagecache we must now flush all the 2025 * dirty data and invalidate caches so that kernel sees 2026 * changes from userspace. It is not enough to just flush 2027 * the quota file since if blocksize < pagesize, invalidation 2028 * of the cache could fail because of other unrelated dirty 2029 * data */ 2030 sync_filesystem(sb); 2031 invalidate_bdev(sb->s_bdev); 2032 } 2033 mutex_lock(&dqopt->dqonoff_mutex); 2034 if (sb_has_quota_loaded(sb, type)) { 2035 error = -EBUSY; 2036 goto out_lock; 2037 } 2038 2039 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2040 /* We don't want quota and atime on quota files (deadlocks 2041 * possible) Also nobody should write to the file - we use 2042 * special IO operations which ignore the immutable bit. */ 2043 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2044 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2045 S_NOQUOTA); 2046 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2047 mutex_unlock(&inode->i_mutex); 2048 /* 2049 * When S_NOQUOTA is set, remove dquot references as no more 2050 * references can be added 2051 */ 2052 __dquot_drop(inode); 2053 } 2054 2055 error = -EIO; 2056 dqopt->files[type] = igrab(inode); 2057 if (!dqopt->files[type]) 2058 goto out_lock; 2059 error = -EINVAL; 2060 if (!fmt->qf_ops->check_quota_file(sb, type)) 2061 goto out_file_init; 2062 2063 dqopt->ops[type] = fmt->qf_ops; 2064 dqopt->info[type].dqi_format = fmt; 2065 dqopt->info[type].dqi_fmt_id = format_id; 2066 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2067 mutex_lock(&dqopt->dqio_mutex); 2068 error = dqopt->ops[type]->read_file_info(sb, type); 2069 if (error < 0) { 2070 mutex_unlock(&dqopt->dqio_mutex); 2071 goto out_file_init; 2072 } 2073 mutex_unlock(&dqopt->dqio_mutex); 2074 spin_lock(&dq_state_lock); 2075 dqopt->flags |= dquot_state_flag(flags, type); 2076 spin_unlock(&dq_state_lock); 2077 2078 add_dquot_ref(sb, type); 2079 mutex_unlock(&dqopt->dqonoff_mutex); 2080 2081 return 0; 2082 2083 out_file_init: 2084 dqopt->files[type] = NULL; 2085 iput(inode); 2086 out_lock: 2087 if (oldflags != -1) { 2088 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2089 /* Set the flags back (in the case of accidental quotaon() 2090 * on a wrong file we don't want to mess up the flags) */ 2091 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2092 inode->i_flags |= oldflags; 2093 mutex_unlock(&inode->i_mutex); 2094 } 2095 mutex_unlock(&dqopt->dqonoff_mutex); 2096 out_fmt: 2097 put_quota_format(fmt); 2098 2099 return error; 2100 } 2101 2102 /* Reenable quotas on remount RW */ 2103 static int vfs_quota_on_remount(struct super_block *sb, int type) 2104 { 2105 struct quota_info *dqopt = sb_dqopt(sb); 2106 struct inode *inode; 2107 int ret; 2108 unsigned int flags; 2109 2110 mutex_lock(&dqopt->dqonoff_mutex); 2111 if (!sb_has_quota_suspended(sb, type)) { 2112 mutex_unlock(&dqopt->dqonoff_mutex); 2113 return 0; 2114 } 2115 inode = dqopt->files[type]; 2116 dqopt->files[type] = NULL; 2117 spin_lock(&dq_state_lock); 2118 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2119 DQUOT_LIMITS_ENABLED, type); 2120 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type); 2121 spin_unlock(&dq_state_lock); 2122 mutex_unlock(&dqopt->dqonoff_mutex); 2123 2124 flags = dquot_generic_flag(flags, type); 2125 ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id, 2126 flags); 2127 iput(inode); 2128 2129 return ret; 2130 } 2131 2132 int vfs_quota_on_path(struct super_block *sb, int type, int format_id, 2133 struct path *path) 2134 { 2135 int error = security_quota_on(path->dentry); 2136 if (error) 2137 return error; 2138 /* Quota file not on the same filesystem? */ 2139 if (path->mnt->mnt_sb != sb) 2140 error = -EXDEV; 2141 else 2142 error = vfs_load_quota_inode(path->dentry->d_inode, type, 2143 format_id, DQUOT_USAGE_ENABLED | 2144 DQUOT_LIMITS_ENABLED); 2145 return error; 2146 } 2147 EXPORT_SYMBOL(vfs_quota_on_path); 2148 2149 int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name, 2150 int remount) 2151 { 2152 struct path path; 2153 int error; 2154 2155 if (remount) 2156 return vfs_quota_on_remount(sb, type); 2157 2158 error = kern_path(name, LOOKUP_FOLLOW, &path); 2159 if (!error) { 2160 error = vfs_quota_on_path(sb, type, format_id, &path); 2161 path_put(&path); 2162 } 2163 return error; 2164 } 2165 EXPORT_SYMBOL(vfs_quota_on); 2166 2167 /* 2168 * More powerful function for turning on quotas allowing setting 2169 * of individual quota flags 2170 */ 2171 int vfs_quota_enable(struct inode *inode, int type, int format_id, 2172 unsigned int flags) 2173 { 2174 int ret = 0; 2175 struct super_block *sb = inode->i_sb; 2176 struct quota_info *dqopt = sb_dqopt(sb); 2177 2178 /* Just unsuspend quotas? */ 2179 if (flags & DQUOT_SUSPENDED) 2180 return vfs_quota_on_remount(sb, type); 2181 if (!flags) 2182 return 0; 2183 /* Just updating flags needed? */ 2184 if (sb_has_quota_loaded(sb, type)) { 2185 mutex_lock(&dqopt->dqonoff_mutex); 2186 /* Now do a reliable test... */ 2187 if (!sb_has_quota_loaded(sb, type)) { 2188 mutex_unlock(&dqopt->dqonoff_mutex); 2189 goto load_quota; 2190 } 2191 if (flags & DQUOT_USAGE_ENABLED && 2192 sb_has_quota_usage_enabled(sb, type)) { 2193 ret = -EBUSY; 2194 goto out_lock; 2195 } 2196 if (flags & DQUOT_LIMITS_ENABLED && 2197 sb_has_quota_limits_enabled(sb, type)) { 2198 ret = -EBUSY; 2199 goto out_lock; 2200 } 2201 spin_lock(&dq_state_lock); 2202 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2203 spin_unlock(&dq_state_lock); 2204 out_lock: 2205 mutex_unlock(&dqopt->dqonoff_mutex); 2206 return ret; 2207 } 2208 2209 load_quota: 2210 return vfs_load_quota_inode(inode, type, format_id, flags); 2211 } 2212 EXPORT_SYMBOL(vfs_quota_enable); 2213 2214 /* 2215 * This function is used when filesystem needs to initialize quotas 2216 * during mount time. 2217 */ 2218 int vfs_quota_on_mount(struct super_block *sb, char *qf_name, 2219 int format_id, int type) 2220 { 2221 struct dentry *dentry; 2222 int error; 2223 2224 mutex_lock(&sb->s_root->d_inode->i_mutex); 2225 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2226 mutex_unlock(&sb->s_root->d_inode->i_mutex); 2227 if (IS_ERR(dentry)) 2228 return PTR_ERR(dentry); 2229 2230 if (!dentry->d_inode) { 2231 error = -ENOENT; 2232 goto out; 2233 } 2234 2235 error = security_quota_on(dentry); 2236 if (!error) 2237 error = vfs_load_quota_inode(dentry->d_inode, type, format_id, 2238 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2239 2240 out: 2241 dput(dentry); 2242 return error; 2243 } 2244 EXPORT_SYMBOL(vfs_quota_on_mount); 2245 2246 /* Wrapper to turn on quotas when remounting rw */ 2247 int vfs_dq_quota_on_remount(struct super_block *sb) 2248 { 2249 int cnt; 2250 int ret = 0, err; 2251 2252 if (!sb->s_qcop || !sb->s_qcop->quota_on) 2253 return -ENOSYS; 2254 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2255 err = sb->s_qcop->quota_on(sb, cnt, 0, NULL, 1); 2256 if (err < 0 && !ret) 2257 ret = err; 2258 } 2259 return ret; 2260 } 2261 EXPORT_SYMBOL(vfs_dq_quota_on_remount); 2262 2263 static inline qsize_t qbtos(qsize_t blocks) 2264 { 2265 return blocks << QIF_DQBLKSIZE_BITS; 2266 } 2267 2268 static inline qsize_t stoqb(qsize_t space) 2269 { 2270 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; 2271 } 2272 2273 /* Generic routine for getting common part of quota structure */ 2274 static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di) 2275 { 2276 struct mem_dqblk *dm = &dquot->dq_dqb; 2277 2278 spin_lock(&dq_data_lock); 2279 di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit); 2280 di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit); 2281 di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace; 2282 di->dqb_ihardlimit = dm->dqb_ihardlimit; 2283 di->dqb_isoftlimit = dm->dqb_isoftlimit; 2284 di->dqb_curinodes = dm->dqb_curinodes; 2285 di->dqb_btime = dm->dqb_btime; 2286 di->dqb_itime = dm->dqb_itime; 2287 di->dqb_valid = QIF_ALL; 2288 spin_unlock(&dq_data_lock); 2289 } 2290 2291 int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, 2292 struct if_dqblk *di) 2293 { 2294 struct dquot *dquot; 2295 2296 dquot = dqget(sb, id, type); 2297 if (!dquot) 2298 return -ESRCH; 2299 do_get_dqblk(dquot, di); 2300 dqput(dquot); 2301 2302 return 0; 2303 } 2304 EXPORT_SYMBOL(vfs_get_dqblk); 2305 2306 /* Generic routine for setting common part of quota structure */ 2307 static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di) 2308 { 2309 struct mem_dqblk *dm = &dquot->dq_dqb; 2310 int check_blim = 0, check_ilim = 0; 2311 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 2312 2313 if ((di->dqb_valid & QIF_BLIMITS && 2314 (di->dqb_bhardlimit > dqi->dqi_maxblimit || 2315 di->dqb_bsoftlimit > dqi->dqi_maxblimit)) || 2316 (di->dqb_valid & QIF_ILIMITS && 2317 (di->dqb_ihardlimit > dqi->dqi_maxilimit || 2318 di->dqb_isoftlimit > dqi->dqi_maxilimit))) 2319 return -ERANGE; 2320 2321 spin_lock(&dq_data_lock); 2322 if (di->dqb_valid & QIF_SPACE) { 2323 dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace; 2324 check_blim = 1; 2325 __set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2326 } 2327 if (di->dqb_valid & QIF_BLIMITS) { 2328 dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit); 2329 dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit); 2330 check_blim = 1; 2331 __set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2332 } 2333 if (di->dqb_valid & QIF_INODES) { 2334 dm->dqb_curinodes = di->dqb_curinodes; 2335 check_ilim = 1; 2336 __set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2337 } 2338 if (di->dqb_valid & QIF_ILIMITS) { 2339 dm->dqb_isoftlimit = di->dqb_isoftlimit; 2340 dm->dqb_ihardlimit = di->dqb_ihardlimit; 2341 check_ilim = 1; 2342 __set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2343 } 2344 if (di->dqb_valid & QIF_BTIME) { 2345 dm->dqb_btime = di->dqb_btime; 2346 check_blim = 1; 2347 __set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2348 } 2349 if (di->dqb_valid & QIF_ITIME) { 2350 dm->dqb_itime = di->dqb_itime; 2351 check_ilim = 1; 2352 __set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2353 } 2354 2355 if (check_blim) { 2356 if (!dm->dqb_bsoftlimit || 2357 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2358 dm->dqb_btime = 0; 2359 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2360 } else if (!(di->dqb_valid & QIF_BTIME)) 2361 /* Set grace only if user hasn't provided his own... */ 2362 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2363 } 2364 if (check_ilim) { 2365 if (!dm->dqb_isoftlimit || 2366 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2367 dm->dqb_itime = 0; 2368 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2369 } else if (!(di->dqb_valid & QIF_ITIME)) 2370 /* Set grace only if user hasn't provided his own... */ 2371 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2372 } 2373 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2374 dm->dqb_isoftlimit) 2375 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2376 else 2377 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2378 spin_unlock(&dq_data_lock); 2379 mark_dquot_dirty(dquot); 2380 2381 return 0; 2382 } 2383 2384 int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, 2385 struct if_dqblk *di) 2386 { 2387 struct dquot *dquot; 2388 int rc; 2389 2390 dquot = dqget(sb, id, type); 2391 if (!dquot) { 2392 rc = -ESRCH; 2393 goto out; 2394 } 2395 rc = do_set_dqblk(dquot, di); 2396 dqput(dquot); 2397 out: 2398 return rc; 2399 } 2400 EXPORT_SYMBOL(vfs_set_dqblk); 2401 2402 /* Generic routine for getting common part of quota file information */ 2403 int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2404 { 2405 struct mem_dqinfo *mi; 2406 2407 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2408 if (!sb_has_quota_active(sb, type)) { 2409 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2410 return -ESRCH; 2411 } 2412 mi = sb_dqopt(sb)->info + type; 2413 spin_lock(&dq_data_lock); 2414 ii->dqi_bgrace = mi->dqi_bgrace; 2415 ii->dqi_igrace = mi->dqi_igrace; 2416 ii->dqi_flags = mi->dqi_flags & DQF_MASK; 2417 ii->dqi_valid = IIF_ALL; 2418 spin_unlock(&dq_data_lock); 2419 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2420 return 0; 2421 } 2422 EXPORT_SYMBOL(vfs_get_dqinfo); 2423 2424 /* Generic routine for setting common part of quota file information */ 2425 int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2426 { 2427 struct mem_dqinfo *mi; 2428 int err = 0; 2429 2430 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2431 if (!sb_has_quota_active(sb, type)) { 2432 err = -ESRCH; 2433 goto out; 2434 } 2435 mi = sb_dqopt(sb)->info + type; 2436 spin_lock(&dq_data_lock); 2437 if (ii->dqi_valid & IIF_BGRACE) 2438 mi->dqi_bgrace = ii->dqi_bgrace; 2439 if (ii->dqi_valid & IIF_IGRACE) 2440 mi->dqi_igrace = ii->dqi_igrace; 2441 if (ii->dqi_valid & IIF_FLAGS) 2442 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | 2443 (ii->dqi_flags & DQF_MASK); 2444 spin_unlock(&dq_data_lock); 2445 mark_info_dirty(sb, type); 2446 /* Force write to disk */ 2447 sb->dq_op->write_info(sb, type); 2448 out: 2449 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2450 return err; 2451 } 2452 EXPORT_SYMBOL(vfs_set_dqinfo); 2453 2454 const struct quotactl_ops vfs_quotactl_ops = { 2455 .quota_on = vfs_quota_on, 2456 .quota_off = vfs_quota_off, 2457 .quota_sync = vfs_quota_sync, 2458 .get_info = vfs_get_dqinfo, 2459 .set_info = vfs_set_dqinfo, 2460 .get_dqblk = vfs_get_dqblk, 2461 .set_dqblk = vfs_set_dqblk 2462 }; 2463 2464 static ctl_table fs_dqstats_table[] = { 2465 { 2466 .procname = "lookups", 2467 .data = &dqstats.lookups, 2468 .maxlen = sizeof(int), 2469 .mode = 0444, 2470 .proc_handler = proc_dointvec, 2471 }, 2472 { 2473 .procname = "drops", 2474 .data = &dqstats.drops, 2475 .maxlen = sizeof(int), 2476 .mode = 0444, 2477 .proc_handler = proc_dointvec, 2478 }, 2479 { 2480 .procname = "reads", 2481 .data = &dqstats.reads, 2482 .maxlen = sizeof(int), 2483 .mode = 0444, 2484 .proc_handler = proc_dointvec, 2485 }, 2486 { 2487 .procname = "writes", 2488 .data = &dqstats.writes, 2489 .maxlen = sizeof(int), 2490 .mode = 0444, 2491 .proc_handler = proc_dointvec, 2492 }, 2493 { 2494 .procname = "cache_hits", 2495 .data = &dqstats.cache_hits, 2496 .maxlen = sizeof(int), 2497 .mode = 0444, 2498 .proc_handler = proc_dointvec, 2499 }, 2500 { 2501 .procname = "allocated_dquots", 2502 .data = &dqstats.allocated_dquots, 2503 .maxlen = sizeof(int), 2504 .mode = 0444, 2505 .proc_handler = proc_dointvec, 2506 }, 2507 { 2508 .procname = "free_dquots", 2509 .data = &dqstats.free_dquots, 2510 .maxlen = sizeof(int), 2511 .mode = 0444, 2512 .proc_handler = proc_dointvec, 2513 }, 2514 { 2515 .procname = "syncs", 2516 .data = &dqstats.syncs, 2517 .maxlen = sizeof(int), 2518 .mode = 0444, 2519 .proc_handler = proc_dointvec, 2520 }, 2521 #ifdef CONFIG_PRINT_QUOTA_WARNING 2522 { 2523 .procname = "warnings", 2524 .data = &flag_print_warnings, 2525 .maxlen = sizeof(int), 2526 .mode = 0644, 2527 .proc_handler = proc_dointvec, 2528 }, 2529 #endif 2530 { }, 2531 }; 2532 2533 static ctl_table fs_table[] = { 2534 { 2535 .procname = "quota", 2536 .mode = 0555, 2537 .child = fs_dqstats_table, 2538 }, 2539 { }, 2540 }; 2541 2542 static ctl_table sys_table[] = { 2543 { 2544 .procname = "fs", 2545 .mode = 0555, 2546 .child = fs_table, 2547 }, 2548 { }, 2549 }; 2550 2551 static int __init dquot_init(void) 2552 { 2553 int i; 2554 unsigned long nr_hash, order; 2555 2556 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2557 2558 register_sysctl_table(sys_table); 2559 2560 dquot_cachep = kmem_cache_create("dquot", 2561 sizeof(struct dquot), sizeof(unsigned long) * 4, 2562 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2563 SLAB_MEM_SPREAD|SLAB_PANIC), 2564 NULL); 2565 2566 order = 0; 2567 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2568 if (!dquot_hash) 2569 panic("Cannot create dquot hash table"); 2570 2571 /* Find power-of-two hlist_heads which can fit into allocation */ 2572 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2573 dq_hash_bits = 0; 2574 do { 2575 dq_hash_bits++; 2576 } while (nr_hash >> dq_hash_bits); 2577 dq_hash_bits--; 2578 2579 nr_hash = 1UL << dq_hash_bits; 2580 dq_hash_mask = nr_hash - 1; 2581 for (i = 0; i < nr_hash; i++) 2582 INIT_HLIST_HEAD(dquot_hash + i); 2583 2584 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", 2585 nr_hash, order, (PAGE_SIZE << order)); 2586 2587 register_shrinker(&dqcache_shrinker); 2588 2589 return 0; 2590 } 2591 module_init(dquot_init); 2592