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 /* 84 * There are three quota SMP locks. dq_list_lock protects all lists with quotas 85 * and quota formats, dqstats structure containing statistics about the lists 86 * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and 87 * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes. 88 * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly 89 * in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects 90 * modifications of quota state (on quotaon and quotaoff) and readers who care 91 * about latest values take it as well. 92 * 93 * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock, 94 * dq_list_lock > dq_state_lock 95 * 96 * Note that some things (eg. sb pointer, type, id) doesn't change during 97 * the life of the dquot structure and so needn't to be protected by a lock 98 * 99 * Any operation working on dquots via inode pointers must hold dqptr_sem. If 100 * operation is just reading pointers from inode (or not using them at all) the 101 * read lock is enough. If pointers are altered function must hold write lock. 102 * Special care needs to be taken about S_NOQUOTA inode flag (marking that 103 * inode is a quota file). Functions adding pointers from inode to dquots have 104 * to check this flag under dqptr_sem and then (if S_NOQUOTA is not set) they 105 * have to do all pointer modifications before dropping dqptr_sem. This makes 106 * sure they cannot race with quotaon which first sets S_NOQUOTA flag and 107 * then drops all pointers to dquots from an inode. 108 * 109 * Each dquot has its dq_lock mutex. Locked dquots might not be referenced 110 * from inodes (dquot_alloc_space() and such don't check the dq_lock). 111 * Currently dquot is locked only when it is being read to memory (or space for 112 * it is being allocated) on the first dqget() and when it is being released on 113 * the last dqput(). The allocation and release oparations are serialized by 114 * the dq_lock and by checking the use count in dquot_release(). Write 115 * operations on dquots don't hold dq_lock as they copy data under dq_data_lock 116 * spinlock to internal buffers before writing. 117 * 118 * Lock ordering (including related VFS locks) is the following: 119 * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock > 120 * dqio_mutex 121 * The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem > 122 * dqptr_sem. But filesystem has to count with the fact that functions such as 123 * dquot_alloc_space() acquire dqptr_sem and they usually have to be called 124 * from inside a transaction to keep filesystem consistency after a crash. Also 125 * filesystems usually want to do some IO on dquot from ->mark_dirty which is 126 * called with dqptr_sem held. 127 * i_mutex on quota files is special (it's below dqio_mutex) 128 */ 129 130 static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock); 131 static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock); 132 __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock); 133 EXPORT_SYMBOL(dq_data_lock); 134 135 #if defined(CONFIG_QUOTA_DEBUG) || defined(CONFIG_PRINT_QUOTA_WARNING) 136 static char *quotatypes[] = INITQFNAMES; 137 #endif 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 /* Mark dquot dirty in atomic manner, and return it's old dirty flag state */ 323 int dquot_mark_dquot_dirty(struct dquot *dquot) 324 { 325 int ret = 1; 326 327 /* If quota is dirty already, we don't have to acquire dq_list_lock */ 328 if (test_bit(DQ_MOD_B, &dquot->dq_flags)) 329 return 1; 330 331 spin_lock(&dq_list_lock); 332 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) { 333 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)-> 334 info[dquot->dq_type].dqi_dirty_list); 335 ret = 0; 336 } 337 spin_unlock(&dq_list_lock); 338 return ret; 339 } 340 EXPORT_SYMBOL(dquot_mark_dquot_dirty); 341 342 /* Dirtify all the dquots - this can block when journalling */ 343 static inline int mark_all_dquot_dirty(struct dquot * const *dquot) 344 { 345 int ret, err, cnt; 346 347 ret = err = 0; 348 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 349 if (dquot[cnt]) 350 /* Even in case of error we have to continue */ 351 ret = mark_dquot_dirty(dquot[cnt]); 352 if (!err) 353 err = ret; 354 } 355 return err; 356 } 357 358 static inline void dqput_all(struct dquot **dquot) 359 { 360 unsigned int cnt; 361 362 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 363 dqput(dquot[cnt]); 364 } 365 366 /* This function needs dq_list_lock */ 367 static inline int clear_dquot_dirty(struct dquot *dquot) 368 { 369 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) 370 return 0; 371 list_del_init(&dquot->dq_dirty); 372 return 1; 373 } 374 375 void mark_info_dirty(struct super_block *sb, int type) 376 { 377 set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags); 378 } 379 EXPORT_SYMBOL(mark_info_dirty); 380 381 /* 382 * Read dquot from disk and alloc space for it 383 */ 384 385 int dquot_acquire(struct dquot *dquot) 386 { 387 int ret = 0, ret2 = 0; 388 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 389 390 mutex_lock(&dquot->dq_lock); 391 mutex_lock(&dqopt->dqio_mutex); 392 if (!test_bit(DQ_READ_B, &dquot->dq_flags)) 393 ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot); 394 if (ret < 0) 395 goto out_iolock; 396 set_bit(DQ_READ_B, &dquot->dq_flags); 397 /* Instantiate dquot if needed */ 398 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) { 399 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); 400 /* Write the info if needed */ 401 if (info_dirty(&dqopt->info[dquot->dq_type])) { 402 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 403 dquot->dq_sb, dquot->dq_type); 404 } 405 if (ret < 0) 406 goto out_iolock; 407 if (ret2 < 0) { 408 ret = ret2; 409 goto out_iolock; 410 } 411 } 412 set_bit(DQ_ACTIVE_B, &dquot->dq_flags); 413 out_iolock: 414 mutex_unlock(&dqopt->dqio_mutex); 415 mutex_unlock(&dquot->dq_lock); 416 return ret; 417 } 418 EXPORT_SYMBOL(dquot_acquire); 419 420 /* 421 * Write dquot to disk 422 */ 423 int dquot_commit(struct dquot *dquot) 424 { 425 int ret = 0, ret2 = 0; 426 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 427 428 mutex_lock(&dqopt->dqio_mutex); 429 spin_lock(&dq_list_lock); 430 if (!clear_dquot_dirty(dquot)) { 431 spin_unlock(&dq_list_lock); 432 goto out_sem; 433 } 434 spin_unlock(&dq_list_lock); 435 /* Inactive dquot can be only if there was error during read/init 436 * => we have better not writing it */ 437 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 438 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); 439 if (info_dirty(&dqopt->info[dquot->dq_type])) { 440 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 441 dquot->dq_sb, dquot->dq_type); 442 } 443 if (ret >= 0) 444 ret = ret2; 445 } 446 out_sem: 447 mutex_unlock(&dqopt->dqio_mutex); 448 return ret; 449 } 450 EXPORT_SYMBOL(dquot_commit); 451 452 /* 453 * Release dquot 454 */ 455 int dquot_release(struct dquot *dquot) 456 { 457 int ret = 0, ret2 = 0; 458 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 459 460 mutex_lock(&dquot->dq_lock); 461 /* Check whether we are not racing with some other dqget() */ 462 if (atomic_read(&dquot->dq_count) > 1) 463 goto out_dqlock; 464 mutex_lock(&dqopt->dqio_mutex); 465 if (dqopt->ops[dquot->dq_type]->release_dqblk) { 466 ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot); 467 /* Write the info */ 468 if (info_dirty(&dqopt->info[dquot->dq_type])) { 469 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 470 dquot->dq_sb, dquot->dq_type); 471 } 472 if (ret >= 0) 473 ret = ret2; 474 } 475 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags); 476 mutex_unlock(&dqopt->dqio_mutex); 477 out_dqlock: 478 mutex_unlock(&dquot->dq_lock); 479 return ret; 480 } 481 EXPORT_SYMBOL(dquot_release); 482 483 void dquot_destroy(struct dquot *dquot) 484 { 485 kmem_cache_free(dquot_cachep, dquot); 486 } 487 EXPORT_SYMBOL(dquot_destroy); 488 489 static inline void do_destroy_dquot(struct dquot *dquot) 490 { 491 dquot->dq_sb->dq_op->destroy_dquot(dquot); 492 } 493 494 /* Invalidate all dquots on the list. Note that this function is called after 495 * quota is disabled and pointers from inodes removed so there cannot be new 496 * quota users. There can still be some users of quotas due to inodes being 497 * just deleted or pruned by prune_icache() (those are not attached to any 498 * list) or parallel quotactl call. We have to wait for such users. 499 */ 500 static void invalidate_dquots(struct super_block *sb, int type) 501 { 502 struct dquot *dquot, *tmp; 503 504 restart: 505 spin_lock(&dq_list_lock); 506 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) { 507 if (dquot->dq_sb != sb) 508 continue; 509 if (dquot->dq_type != type) 510 continue; 511 /* Wait for dquot users */ 512 if (atomic_read(&dquot->dq_count)) { 513 DEFINE_WAIT(wait); 514 515 atomic_inc(&dquot->dq_count); 516 prepare_to_wait(&dquot->dq_wait_unused, &wait, 517 TASK_UNINTERRUPTIBLE); 518 spin_unlock(&dq_list_lock); 519 /* Once dqput() wakes us up, we know it's time to free 520 * the dquot. 521 * IMPORTANT: we rely on the fact that there is always 522 * at most one process waiting for dquot to free. 523 * Otherwise dq_count would be > 1 and we would never 524 * wake up. 525 */ 526 if (atomic_read(&dquot->dq_count) > 1) 527 schedule(); 528 finish_wait(&dquot->dq_wait_unused, &wait); 529 dqput(dquot); 530 /* At this moment dquot() need not exist (it could be 531 * reclaimed by prune_dqcache(). Hence we must 532 * restart. */ 533 goto restart; 534 } 535 /* 536 * Quota now has no users and it has been written on last 537 * dqput() 538 */ 539 remove_dquot_hash(dquot); 540 remove_free_dquot(dquot); 541 remove_inuse(dquot); 542 do_destroy_dquot(dquot); 543 } 544 spin_unlock(&dq_list_lock); 545 } 546 547 /* Call callback for every active dquot on given filesystem */ 548 int dquot_scan_active(struct super_block *sb, 549 int (*fn)(struct dquot *dquot, unsigned long priv), 550 unsigned long priv) 551 { 552 struct dquot *dquot, *old_dquot = NULL; 553 int ret = 0; 554 555 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 556 spin_lock(&dq_list_lock); 557 list_for_each_entry(dquot, &inuse_list, dq_inuse) { 558 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) 559 continue; 560 if (dquot->dq_sb != sb) 561 continue; 562 /* Now we have active dquot so we can just increase use count */ 563 atomic_inc(&dquot->dq_count); 564 dqstats.lookups++; 565 spin_unlock(&dq_list_lock); 566 dqput(old_dquot); 567 old_dquot = dquot; 568 ret = fn(dquot, priv); 569 if (ret < 0) 570 goto out; 571 spin_lock(&dq_list_lock); 572 /* We are safe to continue now because our dquot could not 573 * be moved out of the inuse list while we hold the reference */ 574 } 575 spin_unlock(&dq_list_lock); 576 out: 577 dqput(old_dquot); 578 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 579 return ret; 580 } 581 EXPORT_SYMBOL(dquot_scan_active); 582 583 int vfs_quota_sync(struct super_block *sb, int type, int wait) 584 { 585 struct list_head *dirty; 586 struct dquot *dquot; 587 struct quota_info *dqopt = sb_dqopt(sb); 588 int cnt; 589 590 mutex_lock(&dqopt->dqonoff_mutex); 591 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 592 if (type != -1 && cnt != type) 593 continue; 594 if (!sb_has_quota_active(sb, cnt)) 595 continue; 596 spin_lock(&dq_list_lock); 597 dirty = &dqopt->info[cnt].dqi_dirty_list; 598 while (!list_empty(dirty)) { 599 dquot = list_first_entry(dirty, struct dquot, 600 dq_dirty); 601 /* Dirty and inactive can be only bad dquot... */ 602 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 603 clear_dquot_dirty(dquot); 604 continue; 605 } 606 /* Now we have active dquot from which someone is 607 * holding reference so we can safely just increase 608 * use count */ 609 atomic_inc(&dquot->dq_count); 610 dqstats.lookups++; 611 spin_unlock(&dq_list_lock); 612 sb->dq_op->write_dquot(dquot); 613 dqput(dquot); 614 spin_lock(&dq_list_lock); 615 } 616 spin_unlock(&dq_list_lock); 617 } 618 619 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 620 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt) 621 && info_dirty(&dqopt->info[cnt])) 622 sb->dq_op->write_info(sb, cnt); 623 spin_lock(&dq_list_lock); 624 dqstats.syncs++; 625 spin_unlock(&dq_list_lock); 626 mutex_unlock(&dqopt->dqonoff_mutex); 627 628 if (!wait || (sb_dqopt(sb)->flags & DQUOT_QUOTA_SYS_FILE)) 629 return 0; 630 631 /* This is not very clever (and fast) but currently I don't know about 632 * any other simple way of getting quota data to disk and we must get 633 * them there for userspace to be visible... */ 634 if (sb->s_op->sync_fs) 635 sb->s_op->sync_fs(sb, 1); 636 sync_blockdev(sb->s_bdev); 637 638 /* 639 * Now when everything is written we can discard the pagecache so 640 * that userspace sees the changes. 641 */ 642 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 643 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 644 if (type != -1 && cnt != type) 645 continue; 646 if (!sb_has_quota_active(sb, cnt)) 647 continue; 648 mutex_lock_nested(&sb_dqopt(sb)->files[cnt]->i_mutex, 649 I_MUTEX_QUOTA); 650 truncate_inode_pages(&sb_dqopt(sb)->files[cnt]->i_data, 0); 651 mutex_unlock(&sb_dqopt(sb)->files[cnt]->i_mutex); 652 } 653 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 654 655 return 0; 656 } 657 EXPORT_SYMBOL(vfs_quota_sync); 658 659 /* Free unused dquots from cache */ 660 static void prune_dqcache(int count) 661 { 662 struct list_head *head; 663 struct dquot *dquot; 664 665 head = free_dquots.prev; 666 while (head != &free_dquots && count) { 667 dquot = list_entry(head, struct dquot, dq_free); 668 remove_dquot_hash(dquot); 669 remove_free_dquot(dquot); 670 remove_inuse(dquot); 671 do_destroy_dquot(dquot); 672 count--; 673 head = free_dquots.prev; 674 } 675 } 676 677 /* 678 * This is called from kswapd when we think we need some 679 * more memory 680 */ 681 682 static int shrink_dqcache_memory(int nr, gfp_t gfp_mask) 683 { 684 if (nr) { 685 spin_lock(&dq_list_lock); 686 prune_dqcache(nr); 687 spin_unlock(&dq_list_lock); 688 } 689 return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure; 690 } 691 692 static struct shrinker dqcache_shrinker = { 693 .shrink = shrink_dqcache_memory, 694 .seeks = DEFAULT_SEEKS, 695 }; 696 697 /* 698 * Put reference to dquot 699 * NOTE: If you change this function please check whether dqput_blocks() works right... 700 */ 701 void dqput(struct dquot *dquot) 702 { 703 int ret; 704 705 if (!dquot) 706 return; 707 #ifdef CONFIG_QUOTA_DEBUG 708 if (!atomic_read(&dquot->dq_count)) { 709 printk("VFS: dqput: trying to free free dquot\n"); 710 printk("VFS: device %s, dquot of %s %d\n", 711 dquot->dq_sb->s_id, 712 quotatypes[dquot->dq_type], 713 dquot->dq_id); 714 BUG(); 715 } 716 #endif 717 718 spin_lock(&dq_list_lock); 719 dqstats.drops++; 720 spin_unlock(&dq_list_lock); 721 we_slept: 722 spin_lock(&dq_list_lock); 723 if (atomic_read(&dquot->dq_count) > 1) { 724 /* We have more than one user... nothing to do */ 725 atomic_dec(&dquot->dq_count); 726 /* Releasing dquot during quotaoff phase? */ 727 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) && 728 atomic_read(&dquot->dq_count) == 1) 729 wake_up(&dquot->dq_wait_unused); 730 spin_unlock(&dq_list_lock); 731 return; 732 } 733 /* Need to release dquot? */ 734 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { 735 spin_unlock(&dq_list_lock); 736 /* Commit dquot before releasing */ 737 ret = dquot->dq_sb->dq_op->write_dquot(dquot); 738 if (ret < 0) { 739 printk(KERN_ERR "VFS: cannot write quota structure on " 740 "device %s (error %d). Quota may get out of " 741 "sync!\n", dquot->dq_sb->s_id, ret); 742 /* 743 * We clear dirty bit anyway, so that we avoid 744 * infinite loop here 745 */ 746 spin_lock(&dq_list_lock); 747 clear_dquot_dirty(dquot); 748 spin_unlock(&dq_list_lock); 749 } 750 goto we_slept; 751 } 752 /* Clear flag in case dquot was inactive (something bad happened) */ 753 clear_dquot_dirty(dquot); 754 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 755 spin_unlock(&dq_list_lock); 756 dquot->dq_sb->dq_op->release_dquot(dquot); 757 goto we_slept; 758 } 759 atomic_dec(&dquot->dq_count); 760 #ifdef CONFIG_QUOTA_DEBUG 761 /* sanity check */ 762 BUG_ON(!list_empty(&dquot->dq_free)); 763 #endif 764 put_dquot_last(dquot); 765 spin_unlock(&dq_list_lock); 766 } 767 EXPORT_SYMBOL(dqput); 768 769 struct dquot *dquot_alloc(struct super_block *sb, int type) 770 { 771 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); 772 } 773 EXPORT_SYMBOL(dquot_alloc); 774 775 static struct dquot *get_empty_dquot(struct super_block *sb, int type) 776 { 777 struct dquot *dquot; 778 779 dquot = sb->dq_op->alloc_dquot(sb, type); 780 if(!dquot) 781 return NULL; 782 783 mutex_init(&dquot->dq_lock); 784 INIT_LIST_HEAD(&dquot->dq_free); 785 INIT_LIST_HEAD(&dquot->dq_inuse); 786 INIT_HLIST_NODE(&dquot->dq_hash); 787 INIT_LIST_HEAD(&dquot->dq_dirty); 788 init_waitqueue_head(&dquot->dq_wait_unused); 789 dquot->dq_sb = sb; 790 dquot->dq_type = type; 791 atomic_set(&dquot->dq_count, 1); 792 793 return dquot; 794 } 795 796 /* 797 * Get reference to dquot 798 * 799 * Locking is slightly tricky here. We are guarded from parallel quotaoff() 800 * destroying our dquot by: 801 * a) checking for quota flags under dq_list_lock and 802 * b) getting a reference to dquot before we release dq_list_lock 803 */ 804 struct dquot *dqget(struct super_block *sb, unsigned int id, int type) 805 { 806 unsigned int hashent = hashfn(sb, id, type); 807 struct dquot *dquot = NULL, *empty = NULL; 808 809 if (!sb_has_quota_active(sb, type)) 810 return NULL; 811 we_slept: 812 spin_lock(&dq_list_lock); 813 spin_lock(&dq_state_lock); 814 if (!sb_has_quota_active(sb, type)) { 815 spin_unlock(&dq_state_lock); 816 spin_unlock(&dq_list_lock); 817 goto out; 818 } 819 spin_unlock(&dq_state_lock); 820 821 dquot = find_dquot(hashent, sb, id, type); 822 if (!dquot) { 823 if (!empty) { 824 spin_unlock(&dq_list_lock); 825 empty = get_empty_dquot(sb, type); 826 if (!empty) 827 schedule(); /* Try to wait for a moment... */ 828 goto we_slept; 829 } 830 dquot = empty; 831 empty = NULL; 832 dquot->dq_id = id; 833 /* all dquots go on the inuse_list */ 834 put_inuse(dquot); 835 /* hash it first so it can be found */ 836 insert_dquot_hash(dquot); 837 dqstats.lookups++; 838 spin_unlock(&dq_list_lock); 839 } else { 840 if (!atomic_read(&dquot->dq_count)) 841 remove_free_dquot(dquot); 842 atomic_inc(&dquot->dq_count); 843 dqstats.cache_hits++; 844 dqstats.lookups++; 845 spin_unlock(&dq_list_lock); 846 } 847 /* Wait for dq_lock - after this we know that either dquot_release() is 848 * already finished or it will be canceled due to dq_count > 1 test */ 849 wait_on_dquot(dquot); 850 /* Read the dquot / allocate space in quota file */ 851 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && 852 sb->dq_op->acquire_dquot(dquot) < 0) { 853 dqput(dquot); 854 dquot = NULL; 855 goto out; 856 } 857 #ifdef CONFIG_QUOTA_DEBUG 858 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ 859 #endif 860 out: 861 if (empty) 862 do_destroy_dquot(empty); 863 864 return dquot; 865 } 866 EXPORT_SYMBOL(dqget); 867 868 static int dqinit_needed(struct inode *inode, int type) 869 { 870 int cnt; 871 872 if (IS_NOQUOTA(inode)) 873 return 0; 874 if (type != -1) 875 return !inode->i_dquot[type]; 876 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 877 if (!inode->i_dquot[cnt]) 878 return 1; 879 return 0; 880 } 881 882 /* This routine is guarded by dqonoff_mutex mutex */ 883 static void add_dquot_ref(struct super_block *sb, int type) 884 { 885 struct inode *inode, *old_inode = NULL; 886 #ifdef CONFIG_QUOTA_DEBUG 887 int reserved = 0; 888 #endif 889 890 spin_lock(&inode_lock); 891 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 892 if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE|I_NEW)) 893 continue; 894 #ifdef CONFIG_QUOTA_DEBUG 895 if (unlikely(inode_get_rsv_space(inode) > 0)) 896 reserved = 1; 897 #endif 898 if (!atomic_read(&inode->i_writecount)) 899 continue; 900 if (!dqinit_needed(inode, type)) 901 continue; 902 903 __iget(inode); 904 spin_unlock(&inode_lock); 905 906 iput(old_inode); 907 __dquot_initialize(inode, type); 908 /* We hold a reference to 'inode' so it couldn't have been 909 * removed from s_inodes list while we dropped the inode_lock. 910 * We cannot iput the inode now as we can be holding the last 911 * reference and we cannot iput it under inode_lock. So we 912 * keep the reference and iput it later. */ 913 old_inode = inode; 914 spin_lock(&inode_lock); 915 } 916 spin_unlock(&inode_lock); 917 iput(old_inode); 918 919 #ifdef CONFIG_QUOTA_DEBUG 920 if (reserved) { 921 printk(KERN_WARNING "VFS (%s): Writes happened before quota" 922 " was turned on thus quota information is probably " 923 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 924 } 925 #endif 926 } 927 928 /* 929 * Return 0 if dqput() won't block. 930 * (note that 1 doesn't necessarily mean blocking) 931 */ 932 static inline int dqput_blocks(struct dquot *dquot) 933 { 934 if (atomic_read(&dquot->dq_count) <= 1) 935 return 1; 936 return 0; 937 } 938 939 /* 940 * Remove references to dquots from inode and add dquot to list for freeing 941 * if we have the last referece to dquot 942 * We can't race with anybody because we hold dqptr_sem for writing... 943 */ 944 static int remove_inode_dquot_ref(struct inode *inode, int type, 945 struct list_head *tofree_head) 946 { 947 struct dquot *dquot = inode->i_dquot[type]; 948 949 inode->i_dquot[type] = NULL; 950 if (dquot) { 951 if (dqput_blocks(dquot)) { 952 #ifdef CONFIG_QUOTA_DEBUG 953 if (atomic_read(&dquot->dq_count) != 1) 954 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count)); 955 #endif 956 spin_lock(&dq_list_lock); 957 /* As dquot must have currently users it can't be on 958 * the free list... */ 959 list_add(&dquot->dq_free, tofree_head); 960 spin_unlock(&dq_list_lock); 961 return 1; 962 } 963 else 964 dqput(dquot); /* We have guaranteed we won't block */ 965 } 966 return 0; 967 } 968 969 /* 970 * Free list of dquots 971 * Dquots are removed from inodes and no new references can be got so we are 972 * the only ones holding reference 973 */ 974 static void put_dquot_list(struct list_head *tofree_head) 975 { 976 struct list_head *act_head; 977 struct dquot *dquot; 978 979 act_head = tofree_head->next; 980 while (act_head != tofree_head) { 981 dquot = list_entry(act_head, struct dquot, dq_free); 982 act_head = act_head->next; 983 /* Remove dquot from the list so we won't have problems... */ 984 list_del_init(&dquot->dq_free); 985 dqput(dquot); 986 } 987 } 988 989 static void remove_dquot_ref(struct super_block *sb, int type, 990 struct list_head *tofree_head) 991 { 992 struct inode *inode; 993 994 spin_lock(&inode_lock); 995 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 996 /* 997 * We have to scan also I_NEW inodes because they can already 998 * have quota pointer initialized. Luckily, we need to touch 999 * only quota pointers and these have separate locking 1000 * (dqptr_sem). 1001 */ 1002 if (!IS_NOQUOTA(inode)) 1003 remove_inode_dquot_ref(inode, type, tofree_head); 1004 } 1005 spin_unlock(&inode_lock); 1006 } 1007 1008 /* Gather all references from inodes and drop them */ 1009 static void drop_dquot_ref(struct super_block *sb, int type) 1010 { 1011 LIST_HEAD(tofree_head); 1012 1013 if (sb->dq_op) { 1014 down_write(&sb_dqopt(sb)->dqptr_sem); 1015 remove_dquot_ref(sb, type, &tofree_head); 1016 up_write(&sb_dqopt(sb)->dqptr_sem); 1017 put_dquot_list(&tofree_head); 1018 } 1019 } 1020 1021 static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1022 { 1023 dquot->dq_dqb.dqb_curinodes += number; 1024 } 1025 1026 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1027 { 1028 dquot->dq_dqb.dqb_curspace += number; 1029 } 1030 1031 static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1032 { 1033 dquot->dq_dqb.dqb_rsvspace += number; 1034 } 1035 1036 /* 1037 * Claim reserved quota space 1038 */ 1039 static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1040 { 1041 if (dquot->dq_dqb.dqb_rsvspace < number) { 1042 WARN_ON_ONCE(1); 1043 number = dquot->dq_dqb.dqb_rsvspace; 1044 } 1045 dquot->dq_dqb.dqb_curspace += number; 1046 dquot->dq_dqb.dqb_rsvspace -= number; 1047 } 1048 1049 static inline 1050 void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1051 { 1052 if (dquot->dq_dqb.dqb_rsvspace >= number) 1053 dquot->dq_dqb.dqb_rsvspace -= number; 1054 else { 1055 WARN_ON_ONCE(1); 1056 dquot->dq_dqb.dqb_rsvspace = 0; 1057 } 1058 } 1059 1060 static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1061 { 1062 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1063 dquot->dq_dqb.dqb_curinodes >= number) 1064 dquot->dq_dqb.dqb_curinodes -= number; 1065 else 1066 dquot->dq_dqb.dqb_curinodes = 0; 1067 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1068 dquot->dq_dqb.dqb_itime = (time_t) 0; 1069 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1070 } 1071 1072 static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1073 { 1074 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1075 dquot->dq_dqb.dqb_curspace >= number) 1076 dquot->dq_dqb.dqb_curspace -= number; 1077 else 1078 dquot->dq_dqb.dqb_curspace = 0; 1079 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1080 dquot->dq_dqb.dqb_btime = (time_t) 0; 1081 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1082 } 1083 1084 static int warning_issued(struct dquot *dquot, const int warntype) 1085 { 1086 int flag = (warntype == QUOTA_NL_BHARDWARN || 1087 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1088 ((warntype == QUOTA_NL_IHARDWARN || 1089 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1090 1091 if (!flag) 1092 return 0; 1093 return test_and_set_bit(flag, &dquot->dq_flags); 1094 } 1095 1096 #ifdef CONFIG_PRINT_QUOTA_WARNING 1097 static int flag_print_warnings = 1; 1098 1099 static int need_print_warning(struct dquot *dquot) 1100 { 1101 if (!flag_print_warnings) 1102 return 0; 1103 1104 switch (dquot->dq_type) { 1105 case USRQUOTA: 1106 return current_fsuid() == dquot->dq_id; 1107 case GRPQUOTA: 1108 return in_group_p(dquot->dq_id); 1109 } 1110 return 0; 1111 } 1112 1113 /* Print warning to user which exceeded quota */ 1114 static void print_warning(struct dquot *dquot, const int warntype) 1115 { 1116 char *msg = NULL; 1117 struct tty_struct *tty; 1118 1119 if (warntype == QUOTA_NL_IHARDBELOW || 1120 warntype == QUOTA_NL_ISOFTBELOW || 1121 warntype == QUOTA_NL_BHARDBELOW || 1122 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot)) 1123 return; 1124 1125 tty = get_current_tty(); 1126 if (!tty) 1127 return; 1128 tty_write_message(tty, dquot->dq_sb->s_id); 1129 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1130 tty_write_message(tty, ": warning, "); 1131 else 1132 tty_write_message(tty, ": write failed, "); 1133 tty_write_message(tty, quotatypes[dquot->dq_type]); 1134 switch (warntype) { 1135 case QUOTA_NL_IHARDWARN: 1136 msg = " file limit reached.\r\n"; 1137 break; 1138 case QUOTA_NL_ISOFTLONGWARN: 1139 msg = " file quota exceeded too long.\r\n"; 1140 break; 1141 case QUOTA_NL_ISOFTWARN: 1142 msg = " file quota exceeded.\r\n"; 1143 break; 1144 case QUOTA_NL_BHARDWARN: 1145 msg = " block limit reached.\r\n"; 1146 break; 1147 case QUOTA_NL_BSOFTLONGWARN: 1148 msg = " block quota exceeded too long.\r\n"; 1149 break; 1150 case QUOTA_NL_BSOFTWARN: 1151 msg = " block quota exceeded.\r\n"; 1152 break; 1153 } 1154 tty_write_message(tty, msg); 1155 tty_kref_put(tty); 1156 } 1157 #endif 1158 1159 /* 1160 * Write warnings to the console and send warning messages over netlink. 1161 * 1162 * Note that this function can sleep. 1163 */ 1164 static void flush_warnings(struct dquot *const *dquots, char *warntype) 1165 { 1166 struct dquot *dq; 1167 int i; 1168 1169 for (i = 0; i < MAXQUOTAS; i++) { 1170 dq = dquots[i]; 1171 if (dq && warntype[i] != QUOTA_NL_NOWARN && 1172 !warning_issued(dq, warntype[i])) { 1173 #ifdef CONFIG_PRINT_QUOTA_WARNING 1174 print_warning(dq, warntype[i]); 1175 #endif 1176 quota_send_warning(dq->dq_type, dq->dq_id, 1177 dq->dq_sb->s_dev, warntype[i]); 1178 } 1179 } 1180 } 1181 1182 static int ignore_hardlimit(struct dquot *dquot) 1183 { 1184 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 1185 1186 return capable(CAP_SYS_RESOURCE) && 1187 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1188 !(info->dqi_flags & V1_DQF_RSQUASH)); 1189 } 1190 1191 /* needs dq_data_lock */ 1192 static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) 1193 { 1194 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1195 1196 *warntype = QUOTA_NL_NOWARN; 1197 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || 1198 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1199 return 0; 1200 1201 if (dquot->dq_dqb.dqb_ihardlimit && 1202 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1203 !ignore_hardlimit(dquot)) { 1204 *warntype = QUOTA_NL_IHARDWARN; 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 && 1211 get_seconds() >= dquot->dq_dqb.dqb_itime && 1212 !ignore_hardlimit(dquot)) { 1213 *warntype = QUOTA_NL_ISOFTLONGWARN; 1214 return -EDQUOT; 1215 } 1216 1217 if (dquot->dq_dqb.dqb_isoftlimit && 1218 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1219 dquot->dq_dqb.dqb_itime == 0) { 1220 *warntype = QUOTA_NL_ISOFTWARN; 1221 dquot->dq_dqb.dqb_itime = get_seconds() + 1222 sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; 1223 } 1224 1225 return 0; 1226 } 1227 1228 /* needs dq_data_lock */ 1229 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) 1230 { 1231 qsize_t tspace; 1232 struct super_block *sb = dquot->dq_sb; 1233 1234 *warntype = QUOTA_NL_NOWARN; 1235 if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) || 1236 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1237 return 0; 1238 1239 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1240 + space; 1241 1242 if (dquot->dq_dqb.dqb_bhardlimit && 1243 tspace > dquot->dq_dqb.dqb_bhardlimit && 1244 !ignore_hardlimit(dquot)) { 1245 if (!prealloc) 1246 *warntype = QUOTA_NL_BHARDWARN; 1247 return -EDQUOT; 1248 } 1249 1250 if (dquot->dq_dqb.dqb_bsoftlimit && 1251 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1252 dquot->dq_dqb.dqb_btime && 1253 get_seconds() >= dquot->dq_dqb.dqb_btime && 1254 !ignore_hardlimit(dquot)) { 1255 if (!prealloc) 1256 *warntype = QUOTA_NL_BSOFTLONGWARN; 1257 return -EDQUOT; 1258 } 1259 1260 if (dquot->dq_dqb.dqb_bsoftlimit && 1261 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1262 dquot->dq_dqb.dqb_btime == 0) { 1263 if (!prealloc) { 1264 *warntype = QUOTA_NL_BSOFTWARN; 1265 dquot->dq_dqb.dqb_btime = get_seconds() + 1266 sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace; 1267 } 1268 else 1269 /* 1270 * We don't allow preallocation to exceed softlimit so exceeding will 1271 * be always printed 1272 */ 1273 return -EDQUOT; 1274 } 1275 1276 return 0; 1277 } 1278 1279 static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1280 { 1281 qsize_t newinodes; 1282 1283 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1284 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1285 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type)) 1286 return QUOTA_NL_NOWARN; 1287 1288 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1289 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1290 return QUOTA_NL_ISOFTBELOW; 1291 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1292 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1293 return QUOTA_NL_IHARDBELOW; 1294 return QUOTA_NL_NOWARN; 1295 } 1296 1297 static int info_bdq_free(struct dquot *dquot, qsize_t space) 1298 { 1299 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1300 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1301 return QUOTA_NL_NOWARN; 1302 1303 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1304 return QUOTA_NL_BSOFTBELOW; 1305 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1306 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1307 return QUOTA_NL_BHARDBELOW; 1308 return QUOTA_NL_NOWARN; 1309 } 1310 1311 /* 1312 * Initialize quota pointers in inode 1313 * 1314 * We do things in a bit complicated way but by that we avoid calling 1315 * dqget() and thus filesystem callbacks under dqptr_sem. 1316 * 1317 * It is better to call this function outside of any transaction as it 1318 * might need a lot of space in journal for dquot structure allocation. 1319 */ 1320 static void __dquot_initialize(struct inode *inode, int type) 1321 { 1322 unsigned int id = 0; 1323 int cnt; 1324 struct dquot *got[MAXQUOTAS]; 1325 struct super_block *sb = inode->i_sb; 1326 qsize_t rsv; 1327 1328 /* First test before acquiring mutex - solves deadlocks when we 1329 * re-enter the quota code and are already holding the mutex */ 1330 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1331 return; 1332 1333 /* First get references to structures we might need. */ 1334 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1335 got[cnt] = NULL; 1336 if (type != -1 && cnt != type) 1337 continue; 1338 switch (cnt) { 1339 case USRQUOTA: 1340 id = inode->i_uid; 1341 break; 1342 case GRPQUOTA: 1343 id = inode->i_gid; 1344 break; 1345 } 1346 got[cnt] = dqget(sb, id, cnt); 1347 } 1348 1349 down_write(&sb_dqopt(sb)->dqptr_sem); 1350 if (IS_NOQUOTA(inode)) 1351 goto out_err; 1352 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1353 if (type != -1 && cnt != type) 1354 continue; 1355 /* Avoid races with quotaoff() */ 1356 if (!sb_has_quota_active(sb, cnt)) 1357 continue; 1358 if (!inode->i_dquot[cnt]) { 1359 inode->i_dquot[cnt] = got[cnt]; 1360 got[cnt] = NULL; 1361 /* 1362 * Make quota reservation system happy if someone 1363 * did a write before quota was turned on 1364 */ 1365 rsv = inode_get_rsv_space(inode); 1366 if (unlikely(rsv)) 1367 dquot_resv_space(inode->i_dquot[cnt], rsv); 1368 } 1369 } 1370 out_err: 1371 up_write(&sb_dqopt(sb)->dqptr_sem); 1372 /* Drop unused references */ 1373 dqput_all(got); 1374 } 1375 1376 void dquot_initialize(struct inode *inode) 1377 { 1378 __dquot_initialize(inode, -1); 1379 } 1380 EXPORT_SYMBOL(dquot_initialize); 1381 1382 /* 1383 * Release all quotas referenced by inode 1384 */ 1385 static void __dquot_drop(struct inode *inode) 1386 { 1387 int cnt; 1388 struct dquot *put[MAXQUOTAS]; 1389 1390 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1391 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1392 put[cnt] = inode->i_dquot[cnt]; 1393 inode->i_dquot[cnt] = NULL; 1394 } 1395 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1396 dqput_all(put); 1397 } 1398 1399 void dquot_drop(struct inode *inode) 1400 { 1401 int cnt; 1402 1403 if (IS_NOQUOTA(inode)) 1404 return; 1405 1406 /* 1407 * Test before calling to rule out calls from proc and such 1408 * where we are not allowed to block. Note that this is 1409 * actually reliable test even without the lock - the caller 1410 * must assure that nobody can come after the DQUOT_DROP and 1411 * add quota pointers back anyway. 1412 */ 1413 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1414 if (inode->i_dquot[cnt]) 1415 break; 1416 } 1417 1418 if (cnt < MAXQUOTAS) 1419 __dquot_drop(inode); 1420 } 1421 EXPORT_SYMBOL(dquot_drop); 1422 1423 /* 1424 * inode_reserved_space is managed internally by quota, and protected by 1425 * i_lock similar to i_blocks+i_bytes. 1426 */ 1427 static qsize_t *inode_reserved_space(struct inode * inode) 1428 { 1429 /* Filesystem must explicitly define it's own method in order to use 1430 * quota reservation interface */ 1431 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1432 return inode->i_sb->dq_op->get_reserved_space(inode); 1433 } 1434 1435 void inode_add_rsv_space(struct inode *inode, qsize_t number) 1436 { 1437 spin_lock(&inode->i_lock); 1438 *inode_reserved_space(inode) += number; 1439 spin_unlock(&inode->i_lock); 1440 } 1441 EXPORT_SYMBOL(inode_add_rsv_space); 1442 1443 void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1444 { 1445 spin_lock(&inode->i_lock); 1446 *inode_reserved_space(inode) -= number; 1447 __inode_add_bytes(inode, number); 1448 spin_unlock(&inode->i_lock); 1449 } 1450 EXPORT_SYMBOL(inode_claim_rsv_space); 1451 1452 void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1453 { 1454 spin_lock(&inode->i_lock); 1455 *inode_reserved_space(inode) -= number; 1456 spin_unlock(&inode->i_lock); 1457 } 1458 EXPORT_SYMBOL(inode_sub_rsv_space); 1459 1460 static qsize_t inode_get_rsv_space(struct inode *inode) 1461 { 1462 qsize_t ret; 1463 1464 if (!inode->i_sb->dq_op->get_reserved_space) 1465 return 0; 1466 spin_lock(&inode->i_lock); 1467 ret = *inode_reserved_space(inode); 1468 spin_unlock(&inode->i_lock); 1469 return ret; 1470 } 1471 1472 static void inode_incr_space(struct inode *inode, qsize_t number, 1473 int reserve) 1474 { 1475 if (reserve) 1476 inode_add_rsv_space(inode, number); 1477 else 1478 inode_add_bytes(inode, number); 1479 } 1480 1481 static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1482 { 1483 if (reserve) 1484 inode_sub_rsv_space(inode, number); 1485 else 1486 inode_sub_bytes(inode, number); 1487 } 1488 1489 /* 1490 * This functions updates i_blocks+i_bytes fields and quota information 1491 * (together with appropriate checks). 1492 * 1493 * NOTE: We absolutely rely on the fact that caller dirties the inode 1494 * (usually helpers in quotaops.h care about this) and holds a handle for 1495 * the current transaction so that dquot write and inode write go into the 1496 * same transaction. 1497 */ 1498 1499 /* 1500 * This operation can block, but only after everything is updated 1501 */ 1502 int __dquot_alloc_space(struct inode *inode, qsize_t number, 1503 int warn, int reserve) 1504 { 1505 int cnt, ret = 0; 1506 char warntype[MAXQUOTAS]; 1507 1508 /* 1509 * First test before acquiring mutex - solves deadlocks when we 1510 * re-enter the quota code and are already holding the mutex 1511 */ 1512 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1513 inode_incr_space(inode, number, reserve); 1514 goto out; 1515 } 1516 1517 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1518 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1519 warntype[cnt] = QUOTA_NL_NOWARN; 1520 1521 spin_lock(&dq_data_lock); 1522 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1523 if (!inode->i_dquot[cnt]) 1524 continue; 1525 ret = check_bdq(inode->i_dquot[cnt], number, !warn, 1526 warntype+cnt); 1527 if (ret) { 1528 spin_unlock(&dq_data_lock); 1529 goto out_flush_warn; 1530 } 1531 } 1532 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1533 if (!inode->i_dquot[cnt]) 1534 continue; 1535 if (reserve) 1536 dquot_resv_space(inode->i_dquot[cnt], number); 1537 else 1538 dquot_incr_space(inode->i_dquot[cnt], number); 1539 } 1540 inode_incr_space(inode, number, reserve); 1541 spin_unlock(&dq_data_lock); 1542 1543 if (reserve) 1544 goto out_flush_warn; 1545 mark_all_dquot_dirty(inode->i_dquot); 1546 out_flush_warn: 1547 flush_warnings(inode->i_dquot, warntype); 1548 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1549 out: 1550 return ret; 1551 } 1552 EXPORT_SYMBOL(__dquot_alloc_space); 1553 1554 /* 1555 * This operation can block, but only after everything is updated 1556 */ 1557 int dquot_alloc_inode(const struct inode *inode) 1558 { 1559 int cnt, ret = 0; 1560 char warntype[MAXQUOTAS]; 1561 1562 /* First test before acquiring mutex - solves deadlocks when we 1563 * re-enter the quota code and are already holding the mutex */ 1564 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1565 return 0; 1566 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1567 warntype[cnt] = QUOTA_NL_NOWARN; 1568 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1569 spin_lock(&dq_data_lock); 1570 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1571 if (!inode->i_dquot[cnt]) 1572 continue; 1573 ret = check_idq(inode->i_dquot[cnt], 1, warntype + cnt); 1574 if (ret) 1575 goto warn_put_all; 1576 } 1577 1578 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1579 if (!inode->i_dquot[cnt]) 1580 continue; 1581 dquot_incr_inodes(inode->i_dquot[cnt], 1); 1582 } 1583 1584 warn_put_all: 1585 spin_unlock(&dq_data_lock); 1586 if (ret == 0) 1587 mark_all_dquot_dirty(inode->i_dquot); 1588 flush_warnings(inode->i_dquot, warntype); 1589 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1590 return ret; 1591 } 1592 EXPORT_SYMBOL(dquot_alloc_inode); 1593 1594 /* 1595 * Convert in-memory reserved quotas to real consumed quotas 1596 */ 1597 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1598 { 1599 int cnt; 1600 1601 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1602 inode_claim_rsv_space(inode, number); 1603 return 0; 1604 } 1605 1606 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1607 spin_lock(&dq_data_lock); 1608 /* Claim reserved quotas to allocated quotas */ 1609 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1610 if (inode->i_dquot[cnt]) 1611 dquot_claim_reserved_space(inode->i_dquot[cnt], 1612 number); 1613 } 1614 /* Update inode bytes */ 1615 inode_claim_rsv_space(inode, number); 1616 spin_unlock(&dq_data_lock); 1617 mark_all_dquot_dirty(inode->i_dquot); 1618 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1619 return 0; 1620 } 1621 EXPORT_SYMBOL(dquot_claim_space_nodirty); 1622 1623 /* 1624 * This operation can block, but only after everything is updated 1625 */ 1626 void __dquot_free_space(struct inode *inode, qsize_t number, int reserve) 1627 { 1628 unsigned int cnt; 1629 char warntype[MAXQUOTAS]; 1630 1631 /* First test before acquiring mutex - solves deadlocks when we 1632 * re-enter the quota code and are already holding the mutex */ 1633 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1634 inode_decr_space(inode, number, reserve); 1635 return; 1636 } 1637 1638 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1639 spin_lock(&dq_data_lock); 1640 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1641 if (!inode->i_dquot[cnt]) 1642 continue; 1643 warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number); 1644 if (reserve) 1645 dquot_free_reserved_space(inode->i_dquot[cnt], number); 1646 else 1647 dquot_decr_space(inode->i_dquot[cnt], number); 1648 } 1649 inode_decr_space(inode, number, reserve); 1650 spin_unlock(&dq_data_lock); 1651 1652 if (reserve) 1653 goto out_unlock; 1654 mark_all_dquot_dirty(inode->i_dquot); 1655 out_unlock: 1656 flush_warnings(inode->i_dquot, warntype); 1657 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1658 } 1659 EXPORT_SYMBOL(__dquot_free_space); 1660 1661 /* 1662 * This operation can block, but only after everything is updated 1663 */ 1664 void dquot_free_inode(const struct inode *inode) 1665 { 1666 unsigned int cnt; 1667 char warntype[MAXQUOTAS]; 1668 1669 /* First test before acquiring mutex - solves deadlocks when we 1670 * re-enter the quota code and are already holding the mutex */ 1671 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1672 return; 1673 1674 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1675 spin_lock(&dq_data_lock); 1676 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1677 if (!inode->i_dquot[cnt]) 1678 continue; 1679 warntype[cnt] = info_idq_free(inode->i_dquot[cnt], 1); 1680 dquot_decr_inodes(inode->i_dquot[cnt], 1); 1681 } 1682 spin_unlock(&dq_data_lock); 1683 mark_all_dquot_dirty(inode->i_dquot); 1684 flush_warnings(inode->i_dquot, warntype); 1685 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1686 } 1687 EXPORT_SYMBOL(dquot_free_inode); 1688 1689 /* 1690 * Transfer the number of inode and blocks from one diskquota to an other. 1691 * 1692 * This operation can block, but only after everything is updated 1693 * A transaction must be started when entering this function. 1694 */ 1695 static int __dquot_transfer(struct inode *inode, qid_t *chid, unsigned long mask) 1696 { 1697 qsize_t space, cur_space; 1698 qsize_t rsv_space = 0; 1699 struct dquot *transfer_from[MAXQUOTAS]; 1700 struct dquot *transfer_to[MAXQUOTAS]; 1701 int cnt, ret = 0; 1702 char warntype_to[MAXQUOTAS]; 1703 char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS]; 1704 1705 /* First test before acquiring mutex - solves deadlocks when we 1706 * re-enter the quota code and are already holding the mutex */ 1707 if (IS_NOQUOTA(inode)) 1708 return 0; 1709 /* Initialize the arrays */ 1710 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1711 transfer_from[cnt] = NULL; 1712 transfer_to[cnt] = NULL; 1713 warntype_to[cnt] = QUOTA_NL_NOWARN; 1714 } 1715 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1716 if (mask & (1 << cnt)) 1717 transfer_to[cnt] = dqget(inode->i_sb, chid[cnt], cnt); 1718 } 1719 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1720 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1721 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1722 goto put_all; 1723 } 1724 spin_lock(&dq_data_lock); 1725 cur_space = inode_get_bytes(inode); 1726 rsv_space = inode_get_rsv_space(inode); 1727 space = cur_space + rsv_space; 1728 /* Build the transfer_from list and check the limits */ 1729 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1730 if (!transfer_to[cnt]) 1731 continue; 1732 transfer_from[cnt] = inode->i_dquot[cnt]; 1733 ret = check_idq(transfer_to[cnt], 1, warntype_to + cnt); 1734 if (ret) 1735 goto over_quota; 1736 ret = check_bdq(transfer_to[cnt], space, 0, warntype_to + cnt); 1737 if (ret) 1738 goto over_quota; 1739 } 1740 1741 /* 1742 * Finally perform the needed transfer from transfer_from to transfer_to 1743 */ 1744 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1745 /* 1746 * Skip changes for same uid or gid or for turned off quota-type. 1747 */ 1748 if (!transfer_to[cnt]) 1749 continue; 1750 1751 /* Due to IO error we might not have transfer_from[] structure */ 1752 if (transfer_from[cnt]) { 1753 warntype_from_inodes[cnt] = 1754 info_idq_free(transfer_from[cnt], 1); 1755 warntype_from_space[cnt] = 1756 info_bdq_free(transfer_from[cnt], space); 1757 dquot_decr_inodes(transfer_from[cnt], 1); 1758 dquot_decr_space(transfer_from[cnt], cur_space); 1759 dquot_free_reserved_space(transfer_from[cnt], 1760 rsv_space); 1761 } 1762 1763 dquot_incr_inodes(transfer_to[cnt], 1); 1764 dquot_incr_space(transfer_to[cnt], cur_space); 1765 dquot_resv_space(transfer_to[cnt], rsv_space); 1766 1767 inode->i_dquot[cnt] = transfer_to[cnt]; 1768 } 1769 spin_unlock(&dq_data_lock); 1770 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1771 1772 mark_all_dquot_dirty(transfer_from); 1773 mark_all_dquot_dirty(transfer_to); 1774 /* The reference we got is transferred to the inode */ 1775 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1776 transfer_to[cnt] = NULL; 1777 warn_put_all: 1778 flush_warnings(transfer_to, warntype_to); 1779 flush_warnings(transfer_from, warntype_from_inodes); 1780 flush_warnings(transfer_from, warntype_from_space); 1781 put_all: 1782 dqput_all(transfer_from); 1783 dqput_all(transfer_to); 1784 return ret; 1785 over_quota: 1786 spin_unlock(&dq_data_lock); 1787 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1788 /* Clear dquot pointers we don't want to dqput() */ 1789 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1790 transfer_from[cnt] = NULL; 1791 goto warn_put_all; 1792 } 1793 1794 /* Wrapper for transferring ownership of an inode for uid/gid only 1795 * Called from FSXXX_setattr() 1796 */ 1797 int dquot_transfer(struct inode *inode, struct iattr *iattr) 1798 { 1799 qid_t chid[MAXQUOTAS]; 1800 unsigned long mask = 0; 1801 1802 if (iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) { 1803 mask |= 1 << USRQUOTA; 1804 chid[USRQUOTA] = iattr->ia_uid; 1805 } 1806 if (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid) { 1807 mask |= 1 << GRPQUOTA; 1808 chid[GRPQUOTA] = iattr->ia_gid; 1809 } 1810 if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) { 1811 dquot_initialize(inode); 1812 return __dquot_transfer(inode, chid, mask); 1813 } 1814 return 0; 1815 } 1816 EXPORT_SYMBOL(dquot_transfer); 1817 1818 /* 1819 * Write info of quota file to disk 1820 */ 1821 int dquot_commit_info(struct super_block *sb, int type) 1822 { 1823 int ret; 1824 struct quota_info *dqopt = sb_dqopt(sb); 1825 1826 mutex_lock(&dqopt->dqio_mutex); 1827 ret = dqopt->ops[type]->write_file_info(sb, type); 1828 mutex_unlock(&dqopt->dqio_mutex); 1829 return ret; 1830 } 1831 EXPORT_SYMBOL(dquot_commit_info); 1832 1833 /* 1834 * Definitions of diskquota operations. 1835 */ 1836 const struct dquot_operations dquot_operations = { 1837 .write_dquot = dquot_commit, 1838 .acquire_dquot = dquot_acquire, 1839 .release_dquot = dquot_release, 1840 .mark_dirty = dquot_mark_dquot_dirty, 1841 .write_info = dquot_commit_info, 1842 .alloc_dquot = dquot_alloc, 1843 .destroy_dquot = dquot_destroy, 1844 }; 1845 1846 /* 1847 * Generic helper for ->open on filesystems supporting disk quotas. 1848 */ 1849 int dquot_file_open(struct inode *inode, struct file *file) 1850 { 1851 int error; 1852 1853 error = generic_file_open(inode, file); 1854 if (!error && (file->f_mode & FMODE_WRITE)) 1855 dquot_initialize(inode); 1856 return error; 1857 } 1858 EXPORT_SYMBOL(dquot_file_open); 1859 1860 /* 1861 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 1862 */ 1863 int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags) 1864 { 1865 int cnt, ret = 0; 1866 struct quota_info *dqopt = sb_dqopt(sb); 1867 struct inode *toputinode[MAXQUOTAS]; 1868 1869 /* Cannot turn off usage accounting without turning off limits, or 1870 * suspend quotas and simultaneously turn quotas off. */ 1871 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 1872 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 1873 DQUOT_USAGE_ENABLED))) 1874 return -EINVAL; 1875 1876 /* We need to serialize quota_off() for device */ 1877 mutex_lock(&dqopt->dqonoff_mutex); 1878 1879 /* 1880 * Skip everything if there's nothing to do. We have to do this because 1881 * sometimes we are called when fill_super() failed and calling 1882 * sync_fs() in such cases does no good. 1883 */ 1884 if (!sb_any_quota_loaded(sb)) { 1885 mutex_unlock(&dqopt->dqonoff_mutex); 1886 return 0; 1887 } 1888 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1889 toputinode[cnt] = NULL; 1890 if (type != -1 && cnt != type) 1891 continue; 1892 if (!sb_has_quota_loaded(sb, cnt)) 1893 continue; 1894 1895 if (flags & DQUOT_SUSPENDED) { 1896 spin_lock(&dq_state_lock); 1897 dqopt->flags |= 1898 dquot_state_flag(DQUOT_SUSPENDED, cnt); 1899 spin_unlock(&dq_state_lock); 1900 } else { 1901 spin_lock(&dq_state_lock); 1902 dqopt->flags &= ~dquot_state_flag(flags, cnt); 1903 /* Turning off suspended quotas? */ 1904 if (!sb_has_quota_loaded(sb, cnt) && 1905 sb_has_quota_suspended(sb, cnt)) { 1906 dqopt->flags &= ~dquot_state_flag( 1907 DQUOT_SUSPENDED, cnt); 1908 spin_unlock(&dq_state_lock); 1909 iput(dqopt->files[cnt]); 1910 dqopt->files[cnt] = NULL; 1911 continue; 1912 } 1913 spin_unlock(&dq_state_lock); 1914 } 1915 1916 /* We still have to keep quota loaded? */ 1917 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 1918 continue; 1919 1920 /* Note: these are blocking operations */ 1921 drop_dquot_ref(sb, cnt); 1922 invalidate_dquots(sb, cnt); 1923 /* 1924 * Now all dquots should be invalidated, all writes done so we 1925 * should be only users of the info. No locks needed. 1926 */ 1927 if (info_dirty(&dqopt->info[cnt])) 1928 sb->dq_op->write_info(sb, cnt); 1929 if (dqopt->ops[cnt]->free_file_info) 1930 dqopt->ops[cnt]->free_file_info(sb, cnt); 1931 put_quota_format(dqopt->info[cnt].dqi_format); 1932 1933 toputinode[cnt] = dqopt->files[cnt]; 1934 if (!sb_has_quota_loaded(sb, cnt)) 1935 dqopt->files[cnt] = NULL; 1936 dqopt->info[cnt].dqi_flags = 0; 1937 dqopt->info[cnt].dqi_igrace = 0; 1938 dqopt->info[cnt].dqi_bgrace = 0; 1939 dqopt->ops[cnt] = NULL; 1940 } 1941 mutex_unlock(&dqopt->dqonoff_mutex); 1942 1943 /* Skip syncing and setting flags if quota files are hidden */ 1944 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 1945 goto put_inodes; 1946 1947 /* Sync the superblock so that buffers with quota data are written to 1948 * disk (and so userspace sees correct data afterwards). */ 1949 if (sb->s_op->sync_fs) 1950 sb->s_op->sync_fs(sb, 1); 1951 sync_blockdev(sb->s_bdev); 1952 /* Now the quota files are just ordinary files and we can set the 1953 * inode flags back. Moreover we discard the pagecache so that 1954 * userspace sees the writes we did bypassing the pagecache. We 1955 * must also discard the blockdev buffers so that we see the 1956 * changes done by userspace on the next quotaon() */ 1957 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1958 if (toputinode[cnt]) { 1959 mutex_lock(&dqopt->dqonoff_mutex); 1960 /* If quota was reenabled in the meantime, we have 1961 * nothing to do */ 1962 if (!sb_has_quota_loaded(sb, cnt)) { 1963 mutex_lock_nested(&toputinode[cnt]->i_mutex, 1964 I_MUTEX_QUOTA); 1965 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 1966 S_NOATIME | S_NOQUOTA); 1967 truncate_inode_pages(&toputinode[cnt]->i_data, 1968 0); 1969 mutex_unlock(&toputinode[cnt]->i_mutex); 1970 mark_inode_dirty(toputinode[cnt]); 1971 } 1972 mutex_unlock(&dqopt->dqonoff_mutex); 1973 } 1974 if (sb->s_bdev) 1975 invalidate_bdev(sb->s_bdev); 1976 put_inodes: 1977 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1978 if (toputinode[cnt]) { 1979 /* On remount RO, we keep the inode pointer so that we 1980 * can reenable quota on the subsequent remount RW. We 1981 * have to check 'flags' variable and not use sb_has_ 1982 * function because another quotaon / quotaoff could 1983 * change global state before we got here. We refuse 1984 * to suspend quotas when there is pending delete on 1985 * the quota file... */ 1986 if (!(flags & DQUOT_SUSPENDED)) 1987 iput(toputinode[cnt]); 1988 else if (!toputinode[cnt]->i_nlink) 1989 ret = -EBUSY; 1990 } 1991 return ret; 1992 } 1993 EXPORT_SYMBOL(vfs_quota_disable); 1994 1995 int vfs_quota_off(struct super_block *sb, int type, int remount) 1996 { 1997 return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED : 1998 (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED)); 1999 } 2000 EXPORT_SYMBOL(vfs_quota_off); 2001 /* 2002 * Turn quotas on on a device 2003 */ 2004 2005 /* 2006 * Helper function to turn quotas on when we already have the inode of 2007 * quota file and no quota information is loaded. 2008 */ 2009 static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 2010 unsigned int flags) 2011 { 2012 struct quota_format_type *fmt = find_quota_format(format_id); 2013 struct super_block *sb = inode->i_sb; 2014 struct quota_info *dqopt = sb_dqopt(sb); 2015 int error; 2016 int oldflags = -1; 2017 2018 if (!fmt) 2019 return -ESRCH; 2020 if (!S_ISREG(inode->i_mode)) { 2021 error = -EACCES; 2022 goto out_fmt; 2023 } 2024 if (IS_RDONLY(inode)) { 2025 error = -EROFS; 2026 goto out_fmt; 2027 } 2028 if (!sb->s_op->quota_write || !sb->s_op->quota_read) { 2029 error = -EINVAL; 2030 goto out_fmt; 2031 } 2032 /* Usage always has to be set... */ 2033 if (!(flags & DQUOT_USAGE_ENABLED)) { 2034 error = -EINVAL; 2035 goto out_fmt; 2036 } 2037 2038 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2039 /* As we bypass the pagecache we must now flush all the 2040 * dirty data and invalidate caches so that kernel sees 2041 * changes from userspace. It is not enough to just flush 2042 * the quota file since if blocksize < pagesize, invalidation 2043 * of the cache could fail because of other unrelated dirty 2044 * data */ 2045 sync_filesystem(sb); 2046 invalidate_bdev(sb->s_bdev); 2047 } 2048 mutex_lock(&dqopt->dqonoff_mutex); 2049 if (sb_has_quota_loaded(sb, type)) { 2050 error = -EBUSY; 2051 goto out_lock; 2052 } 2053 2054 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2055 /* We don't want quota and atime on quota files (deadlocks 2056 * possible) Also nobody should write to the file - we use 2057 * special IO operations which ignore the immutable bit. */ 2058 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2059 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2060 S_NOQUOTA); 2061 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2062 mutex_unlock(&inode->i_mutex); 2063 /* 2064 * When S_NOQUOTA is set, remove dquot references as no more 2065 * references can be added 2066 */ 2067 __dquot_drop(inode); 2068 } 2069 2070 error = -EIO; 2071 dqopt->files[type] = igrab(inode); 2072 if (!dqopt->files[type]) 2073 goto out_lock; 2074 error = -EINVAL; 2075 if (!fmt->qf_ops->check_quota_file(sb, type)) 2076 goto out_file_init; 2077 2078 dqopt->ops[type] = fmt->qf_ops; 2079 dqopt->info[type].dqi_format = fmt; 2080 dqopt->info[type].dqi_fmt_id = format_id; 2081 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2082 mutex_lock(&dqopt->dqio_mutex); 2083 error = dqopt->ops[type]->read_file_info(sb, type); 2084 if (error < 0) { 2085 mutex_unlock(&dqopt->dqio_mutex); 2086 goto out_file_init; 2087 } 2088 mutex_unlock(&dqopt->dqio_mutex); 2089 spin_lock(&dq_state_lock); 2090 dqopt->flags |= dquot_state_flag(flags, type); 2091 spin_unlock(&dq_state_lock); 2092 2093 add_dquot_ref(sb, type); 2094 mutex_unlock(&dqopt->dqonoff_mutex); 2095 2096 return 0; 2097 2098 out_file_init: 2099 dqopt->files[type] = NULL; 2100 iput(inode); 2101 out_lock: 2102 if (oldflags != -1) { 2103 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2104 /* Set the flags back (in the case of accidental quotaon() 2105 * on a wrong file we don't want to mess up the flags) */ 2106 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2107 inode->i_flags |= oldflags; 2108 mutex_unlock(&inode->i_mutex); 2109 } 2110 mutex_unlock(&dqopt->dqonoff_mutex); 2111 out_fmt: 2112 put_quota_format(fmt); 2113 2114 return error; 2115 } 2116 2117 /* Reenable quotas on remount RW */ 2118 static int vfs_quota_on_remount(struct super_block *sb, int type) 2119 { 2120 struct quota_info *dqopt = sb_dqopt(sb); 2121 struct inode *inode; 2122 int ret; 2123 unsigned int flags; 2124 2125 mutex_lock(&dqopt->dqonoff_mutex); 2126 if (!sb_has_quota_suspended(sb, type)) { 2127 mutex_unlock(&dqopt->dqonoff_mutex); 2128 return 0; 2129 } 2130 inode = dqopt->files[type]; 2131 dqopt->files[type] = NULL; 2132 spin_lock(&dq_state_lock); 2133 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2134 DQUOT_LIMITS_ENABLED, type); 2135 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type); 2136 spin_unlock(&dq_state_lock); 2137 mutex_unlock(&dqopt->dqonoff_mutex); 2138 2139 flags = dquot_generic_flag(flags, type); 2140 ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id, 2141 flags); 2142 iput(inode); 2143 2144 return ret; 2145 } 2146 2147 int vfs_quota_on_path(struct super_block *sb, int type, int format_id, 2148 struct path *path) 2149 { 2150 int error = security_quota_on(path->dentry); 2151 if (error) 2152 return error; 2153 /* Quota file not on the same filesystem? */ 2154 if (path->mnt->mnt_sb != sb) 2155 error = -EXDEV; 2156 else 2157 error = vfs_load_quota_inode(path->dentry->d_inode, type, 2158 format_id, DQUOT_USAGE_ENABLED | 2159 DQUOT_LIMITS_ENABLED); 2160 return error; 2161 } 2162 EXPORT_SYMBOL(vfs_quota_on_path); 2163 2164 int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name, 2165 int remount) 2166 { 2167 struct path path; 2168 int error; 2169 2170 if (remount) 2171 return vfs_quota_on_remount(sb, type); 2172 2173 error = kern_path(name, LOOKUP_FOLLOW, &path); 2174 if (!error) { 2175 error = vfs_quota_on_path(sb, type, format_id, &path); 2176 path_put(&path); 2177 } 2178 return error; 2179 } 2180 EXPORT_SYMBOL(vfs_quota_on); 2181 2182 /* 2183 * More powerful function for turning on quotas allowing setting 2184 * of individual quota flags 2185 */ 2186 int vfs_quota_enable(struct inode *inode, int type, int format_id, 2187 unsigned int flags) 2188 { 2189 int ret = 0; 2190 struct super_block *sb = inode->i_sb; 2191 struct quota_info *dqopt = sb_dqopt(sb); 2192 2193 /* Just unsuspend quotas? */ 2194 if (flags & DQUOT_SUSPENDED) 2195 return vfs_quota_on_remount(sb, type); 2196 if (!flags) 2197 return 0; 2198 /* Just updating flags needed? */ 2199 if (sb_has_quota_loaded(sb, type)) { 2200 mutex_lock(&dqopt->dqonoff_mutex); 2201 /* Now do a reliable test... */ 2202 if (!sb_has_quota_loaded(sb, type)) { 2203 mutex_unlock(&dqopt->dqonoff_mutex); 2204 goto load_quota; 2205 } 2206 if (flags & DQUOT_USAGE_ENABLED && 2207 sb_has_quota_usage_enabled(sb, type)) { 2208 ret = -EBUSY; 2209 goto out_lock; 2210 } 2211 if (flags & DQUOT_LIMITS_ENABLED && 2212 sb_has_quota_limits_enabled(sb, type)) { 2213 ret = -EBUSY; 2214 goto out_lock; 2215 } 2216 spin_lock(&dq_state_lock); 2217 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2218 spin_unlock(&dq_state_lock); 2219 out_lock: 2220 mutex_unlock(&dqopt->dqonoff_mutex); 2221 return ret; 2222 } 2223 2224 load_quota: 2225 return vfs_load_quota_inode(inode, type, format_id, flags); 2226 } 2227 EXPORT_SYMBOL(vfs_quota_enable); 2228 2229 /* 2230 * This function is used when filesystem needs to initialize quotas 2231 * during mount time. 2232 */ 2233 int vfs_quota_on_mount(struct super_block *sb, char *qf_name, 2234 int format_id, int type) 2235 { 2236 struct dentry *dentry; 2237 int error; 2238 2239 mutex_lock(&sb->s_root->d_inode->i_mutex); 2240 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2241 mutex_unlock(&sb->s_root->d_inode->i_mutex); 2242 if (IS_ERR(dentry)) 2243 return PTR_ERR(dentry); 2244 2245 if (!dentry->d_inode) { 2246 error = -ENOENT; 2247 goto out; 2248 } 2249 2250 error = security_quota_on(dentry); 2251 if (!error) 2252 error = vfs_load_quota_inode(dentry->d_inode, type, format_id, 2253 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2254 2255 out: 2256 dput(dentry); 2257 return error; 2258 } 2259 EXPORT_SYMBOL(vfs_quota_on_mount); 2260 2261 /* Wrapper to turn on quotas when remounting rw */ 2262 int vfs_dq_quota_on_remount(struct super_block *sb) 2263 { 2264 int cnt; 2265 int ret = 0, err; 2266 2267 if (!sb->s_qcop || !sb->s_qcop->quota_on) 2268 return -ENOSYS; 2269 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2270 err = sb->s_qcop->quota_on(sb, cnt, 0, NULL, 1); 2271 if (err < 0 && !ret) 2272 ret = err; 2273 } 2274 return ret; 2275 } 2276 EXPORT_SYMBOL(vfs_dq_quota_on_remount); 2277 2278 static inline qsize_t qbtos(qsize_t blocks) 2279 { 2280 return blocks << QIF_DQBLKSIZE_BITS; 2281 } 2282 2283 static inline qsize_t stoqb(qsize_t space) 2284 { 2285 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; 2286 } 2287 2288 /* Generic routine for getting common part of quota structure */ 2289 static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di) 2290 { 2291 struct mem_dqblk *dm = &dquot->dq_dqb; 2292 2293 spin_lock(&dq_data_lock); 2294 di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit); 2295 di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit); 2296 di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace; 2297 di->dqb_ihardlimit = dm->dqb_ihardlimit; 2298 di->dqb_isoftlimit = dm->dqb_isoftlimit; 2299 di->dqb_curinodes = dm->dqb_curinodes; 2300 di->dqb_btime = dm->dqb_btime; 2301 di->dqb_itime = dm->dqb_itime; 2302 di->dqb_valid = QIF_ALL; 2303 spin_unlock(&dq_data_lock); 2304 } 2305 2306 int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, 2307 struct if_dqblk *di) 2308 { 2309 struct dquot *dquot; 2310 2311 dquot = dqget(sb, id, type); 2312 if (!dquot) 2313 return -ESRCH; 2314 do_get_dqblk(dquot, di); 2315 dqput(dquot); 2316 2317 return 0; 2318 } 2319 EXPORT_SYMBOL(vfs_get_dqblk); 2320 2321 /* Generic routine for setting common part of quota structure */ 2322 static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di) 2323 { 2324 struct mem_dqblk *dm = &dquot->dq_dqb; 2325 int check_blim = 0, check_ilim = 0; 2326 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 2327 2328 if ((di->dqb_valid & QIF_BLIMITS && 2329 (di->dqb_bhardlimit > dqi->dqi_maxblimit || 2330 di->dqb_bsoftlimit > dqi->dqi_maxblimit)) || 2331 (di->dqb_valid & QIF_ILIMITS && 2332 (di->dqb_ihardlimit > dqi->dqi_maxilimit || 2333 di->dqb_isoftlimit > dqi->dqi_maxilimit))) 2334 return -ERANGE; 2335 2336 spin_lock(&dq_data_lock); 2337 if (di->dqb_valid & QIF_SPACE) { 2338 dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace; 2339 check_blim = 1; 2340 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2341 } 2342 if (di->dqb_valid & QIF_BLIMITS) { 2343 dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit); 2344 dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit); 2345 check_blim = 1; 2346 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2347 } 2348 if (di->dqb_valid & QIF_INODES) { 2349 dm->dqb_curinodes = di->dqb_curinodes; 2350 check_ilim = 1; 2351 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2352 } 2353 if (di->dqb_valid & QIF_ILIMITS) { 2354 dm->dqb_isoftlimit = di->dqb_isoftlimit; 2355 dm->dqb_ihardlimit = di->dqb_ihardlimit; 2356 check_ilim = 1; 2357 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2358 } 2359 if (di->dqb_valid & QIF_BTIME) { 2360 dm->dqb_btime = di->dqb_btime; 2361 check_blim = 1; 2362 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2363 } 2364 if (di->dqb_valid & QIF_ITIME) { 2365 dm->dqb_itime = di->dqb_itime; 2366 check_ilim = 1; 2367 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2368 } 2369 2370 if (check_blim) { 2371 if (!dm->dqb_bsoftlimit || 2372 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2373 dm->dqb_btime = 0; 2374 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2375 } else if (!(di->dqb_valid & QIF_BTIME)) 2376 /* Set grace only if user hasn't provided his own... */ 2377 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2378 } 2379 if (check_ilim) { 2380 if (!dm->dqb_isoftlimit || 2381 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2382 dm->dqb_itime = 0; 2383 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2384 } else if (!(di->dqb_valid & QIF_ITIME)) 2385 /* Set grace only if user hasn't provided his own... */ 2386 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2387 } 2388 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2389 dm->dqb_isoftlimit) 2390 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2391 else 2392 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2393 spin_unlock(&dq_data_lock); 2394 mark_dquot_dirty(dquot); 2395 2396 return 0; 2397 } 2398 2399 int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, 2400 struct if_dqblk *di) 2401 { 2402 struct dquot *dquot; 2403 int rc; 2404 2405 dquot = dqget(sb, id, type); 2406 if (!dquot) { 2407 rc = -ESRCH; 2408 goto out; 2409 } 2410 rc = do_set_dqblk(dquot, di); 2411 dqput(dquot); 2412 out: 2413 return rc; 2414 } 2415 EXPORT_SYMBOL(vfs_set_dqblk); 2416 2417 /* Generic routine for getting common part of quota file information */ 2418 int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2419 { 2420 struct mem_dqinfo *mi; 2421 2422 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2423 if (!sb_has_quota_active(sb, type)) { 2424 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2425 return -ESRCH; 2426 } 2427 mi = sb_dqopt(sb)->info + type; 2428 spin_lock(&dq_data_lock); 2429 ii->dqi_bgrace = mi->dqi_bgrace; 2430 ii->dqi_igrace = mi->dqi_igrace; 2431 ii->dqi_flags = mi->dqi_flags & DQF_MASK; 2432 ii->dqi_valid = IIF_ALL; 2433 spin_unlock(&dq_data_lock); 2434 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2435 return 0; 2436 } 2437 EXPORT_SYMBOL(vfs_get_dqinfo); 2438 2439 /* Generic routine for setting common part of quota file information */ 2440 int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2441 { 2442 struct mem_dqinfo *mi; 2443 int err = 0; 2444 2445 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2446 if (!sb_has_quota_active(sb, type)) { 2447 err = -ESRCH; 2448 goto out; 2449 } 2450 mi = sb_dqopt(sb)->info + type; 2451 spin_lock(&dq_data_lock); 2452 if (ii->dqi_valid & IIF_BGRACE) 2453 mi->dqi_bgrace = ii->dqi_bgrace; 2454 if (ii->dqi_valid & IIF_IGRACE) 2455 mi->dqi_igrace = ii->dqi_igrace; 2456 if (ii->dqi_valid & IIF_FLAGS) 2457 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | 2458 (ii->dqi_flags & DQF_MASK); 2459 spin_unlock(&dq_data_lock); 2460 mark_info_dirty(sb, type); 2461 /* Force write to disk */ 2462 sb->dq_op->write_info(sb, type); 2463 out: 2464 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2465 return err; 2466 } 2467 EXPORT_SYMBOL(vfs_set_dqinfo); 2468 2469 const struct quotactl_ops vfs_quotactl_ops = { 2470 .quota_on = vfs_quota_on, 2471 .quota_off = vfs_quota_off, 2472 .quota_sync = vfs_quota_sync, 2473 .get_info = vfs_get_dqinfo, 2474 .set_info = vfs_set_dqinfo, 2475 .get_dqblk = vfs_get_dqblk, 2476 .set_dqblk = vfs_set_dqblk 2477 }; 2478 2479 static ctl_table fs_dqstats_table[] = { 2480 { 2481 .procname = "lookups", 2482 .data = &dqstats.lookups, 2483 .maxlen = sizeof(int), 2484 .mode = 0444, 2485 .proc_handler = proc_dointvec, 2486 }, 2487 { 2488 .procname = "drops", 2489 .data = &dqstats.drops, 2490 .maxlen = sizeof(int), 2491 .mode = 0444, 2492 .proc_handler = proc_dointvec, 2493 }, 2494 { 2495 .procname = "reads", 2496 .data = &dqstats.reads, 2497 .maxlen = sizeof(int), 2498 .mode = 0444, 2499 .proc_handler = proc_dointvec, 2500 }, 2501 { 2502 .procname = "writes", 2503 .data = &dqstats.writes, 2504 .maxlen = sizeof(int), 2505 .mode = 0444, 2506 .proc_handler = proc_dointvec, 2507 }, 2508 { 2509 .procname = "cache_hits", 2510 .data = &dqstats.cache_hits, 2511 .maxlen = sizeof(int), 2512 .mode = 0444, 2513 .proc_handler = proc_dointvec, 2514 }, 2515 { 2516 .procname = "allocated_dquots", 2517 .data = &dqstats.allocated_dquots, 2518 .maxlen = sizeof(int), 2519 .mode = 0444, 2520 .proc_handler = proc_dointvec, 2521 }, 2522 { 2523 .procname = "free_dquots", 2524 .data = &dqstats.free_dquots, 2525 .maxlen = sizeof(int), 2526 .mode = 0444, 2527 .proc_handler = proc_dointvec, 2528 }, 2529 { 2530 .procname = "syncs", 2531 .data = &dqstats.syncs, 2532 .maxlen = sizeof(int), 2533 .mode = 0444, 2534 .proc_handler = proc_dointvec, 2535 }, 2536 #ifdef CONFIG_PRINT_QUOTA_WARNING 2537 { 2538 .procname = "warnings", 2539 .data = &flag_print_warnings, 2540 .maxlen = sizeof(int), 2541 .mode = 0644, 2542 .proc_handler = proc_dointvec, 2543 }, 2544 #endif 2545 { }, 2546 }; 2547 2548 static ctl_table fs_table[] = { 2549 { 2550 .procname = "quota", 2551 .mode = 0555, 2552 .child = fs_dqstats_table, 2553 }, 2554 { }, 2555 }; 2556 2557 static ctl_table sys_table[] = { 2558 { 2559 .procname = "fs", 2560 .mode = 0555, 2561 .child = fs_table, 2562 }, 2563 { }, 2564 }; 2565 2566 static int __init dquot_init(void) 2567 { 2568 int i; 2569 unsigned long nr_hash, order; 2570 2571 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2572 2573 register_sysctl_table(sys_table); 2574 2575 dquot_cachep = kmem_cache_create("dquot", 2576 sizeof(struct dquot), sizeof(unsigned long) * 4, 2577 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2578 SLAB_MEM_SPREAD|SLAB_PANIC), 2579 NULL); 2580 2581 order = 0; 2582 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2583 if (!dquot_hash) 2584 panic("Cannot create dquot hash table"); 2585 2586 /* Find power-of-two hlist_heads which can fit into allocation */ 2587 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2588 dq_hash_bits = 0; 2589 do { 2590 dq_hash_bits++; 2591 } while (nr_hash >> dq_hash_bits); 2592 dq_hash_bits--; 2593 2594 nr_hash = 1UL << dq_hash_bits; 2595 dq_hash_mask = nr_hash - 1; 2596 for (i = 0; i < nr_hash; i++) 2597 INIT_HLIST_HEAD(dquot_hash + i); 2598 2599 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", 2600 nr_hash, order, (PAGE_SIZE << order)); 2601 2602 register_shrinker(&dqcache_shrinker); 2603 2604 return 0; 2605 } 2606 module_init(dquot_init); 2607