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. 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_inc(DQST_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_dec(DQST_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_inc(DQST_ALLOC_DQUOTS); 295 } 296 297 static inline void remove_inuse(struct dquot *dquot) 298 { 299 dqstats_dec(DQST_ALLOC_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 spin_unlock(&dq_list_lock); 565 dqstats_inc(DQST_LOOKUPS); 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 dquot_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 spin_unlock(&dq_list_lock); 611 dqstats_inc(DQST_LOOKUPS); 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 dqstats_inc(DQST_SYNCS); 624 mutex_unlock(&dqopt->dqonoff_mutex); 625 626 if (!wait || (sb_dqopt(sb)->flags & DQUOT_QUOTA_SYS_FILE)) 627 return 0; 628 629 /* This is not very clever (and fast) but currently I don't know about 630 * any other simple way of getting quota data to disk and we must get 631 * them there for userspace to be visible... */ 632 if (sb->s_op->sync_fs) 633 sb->s_op->sync_fs(sb, 1); 634 sync_blockdev(sb->s_bdev); 635 636 /* 637 * Now when everything is written we can discard the pagecache so 638 * that userspace sees the changes. 639 */ 640 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 641 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 642 if (type != -1 && cnt != type) 643 continue; 644 if (!sb_has_quota_active(sb, cnt)) 645 continue; 646 mutex_lock_nested(&sb_dqopt(sb)->files[cnt]->i_mutex, 647 I_MUTEX_QUOTA); 648 truncate_inode_pages(&sb_dqopt(sb)->files[cnt]->i_data, 0); 649 mutex_unlock(&sb_dqopt(sb)->files[cnt]->i_mutex); 650 } 651 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 652 653 return 0; 654 } 655 EXPORT_SYMBOL(dquot_quota_sync); 656 657 /* Free unused dquots from cache */ 658 static void prune_dqcache(int count) 659 { 660 struct list_head *head; 661 struct dquot *dquot; 662 663 head = free_dquots.prev; 664 while (head != &free_dquots && count) { 665 dquot = list_entry(head, struct dquot, dq_free); 666 remove_dquot_hash(dquot); 667 remove_free_dquot(dquot); 668 remove_inuse(dquot); 669 do_destroy_dquot(dquot); 670 count--; 671 head = free_dquots.prev; 672 } 673 } 674 675 /* 676 * This is called from kswapd when we think we need some 677 * more memory 678 */ 679 static int shrink_dqcache_memory(int nr, gfp_t gfp_mask) 680 { 681 if (nr) { 682 spin_lock(&dq_list_lock); 683 prune_dqcache(nr); 684 spin_unlock(&dq_list_lock); 685 } 686 return ((unsigned) 687 percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS]) 688 /100) * sysctl_vfs_cache_pressure; 689 } 690 691 static struct shrinker dqcache_shrinker = { 692 .shrink = shrink_dqcache_memory, 693 .seeks = DEFAULT_SEEKS, 694 }; 695 696 /* 697 * Put reference to dquot 698 * NOTE: If you change this function please check whether dqput_blocks() works right... 699 */ 700 void dqput(struct dquot *dquot) 701 { 702 int ret; 703 704 if (!dquot) 705 return; 706 #ifdef CONFIG_QUOTA_DEBUG 707 if (!atomic_read(&dquot->dq_count)) { 708 printk("VFS: dqput: trying to free free dquot\n"); 709 printk("VFS: device %s, dquot of %s %d\n", 710 dquot->dq_sb->s_id, 711 quotatypes[dquot->dq_type], 712 dquot->dq_id); 713 BUG(); 714 } 715 #endif 716 dqstats_inc(DQST_DROPS); 717 we_slept: 718 spin_lock(&dq_list_lock); 719 if (atomic_read(&dquot->dq_count) > 1) { 720 /* We have more than one user... nothing to do */ 721 atomic_dec(&dquot->dq_count); 722 /* Releasing dquot during quotaoff phase? */ 723 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) && 724 atomic_read(&dquot->dq_count) == 1) 725 wake_up(&dquot->dq_wait_unused); 726 spin_unlock(&dq_list_lock); 727 return; 728 } 729 /* Need to release dquot? */ 730 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { 731 spin_unlock(&dq_list_lock); 732 /* Commit dquot before releasing */ 733 ret = dquot->dq_sb->dq_op->write_dquot(dquot); 734 if (ret < 0) { 735 printk(KERN_ERR "VFS: cannot write quota structure on " 736 "device %s (error %d). Quota may get out of " 737 "sync!\n", dquot->dq_sb->s_id, ret); 738 /* 739 * We clear dirty bit anyway, so that we avoid 740 * infinite loop here 741 */ 742 spin_lock(&dq_list_lock); 743 clear_dquot_dirty(dquot); 744 spin_unlock(&dq_list_lock); 745 } 746 goto we_slept; 747 } 748 /* Clear flag in case dquot was inactive (something bad happened) */ 749 clear_dquot_dirty(dquot); 750 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 751 spin_unlock(&dq_list_lock); 752 dquot->dq_sb->dq_op->release_dquot(dquot); 753 goto we_slept; 754 } 755 atomic_dec(&dquot->dq_count); 756 #ifdef CONFIG_QUOTA_DEBUG 757 /* sanity check */ 758 BUG_ON(!list_empty(&dquot->dq_free)); 759 #endif 760 put_dquot_last(dquot); 761 spin_unlock(&dq_list_lock); 762 } 763 EXPORT_SYMBOL(dqput); 764 765 struct dquot *dquot_alloc(struct super_block *sb, int type) 766 { 767 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); 768 } 769 EXPORT_SYMBOL(dquot_alloc); 770 771 static struct dquot *get_empty_dquot(struct super_block *sb, int type) 772 { 773 struct dquot *dquot; 774 775 dquot = sb->dq_op->alloc_dquot(sb, type); 776 if(!dquot) 777 return NULL; 778 779 mutex_init(&dquot->dq_lock); 780 INIT_LIST_HEAD(&dquot->dq_free); 781 INIT_LIST_HEAD(&dquot->dq_inuse); 782 INIT_HLIST_NODE(&dquot->dq_hash); 783 INIT_LIST_HEAD(&dquot->dq_dirty); 784 init_waitqueue_head(&dquot->dq_wait_unused); 785 dquot->dq_sb = sb; 786 dquot->dq_type = type; 787 atomic_set(&dquot->dq_count, 1); 788 789 return dquot; 790 } 791 792 /* 793 * Get reference to dquot 794 * 795 * Locking is slightly tricky here. We are guarded from parallel quotaoff() 796 * destroying our dquot by: 797 * a) checking for quota flags under dq_list_lock and 798 * b) getting a reference to dquot before we release dq_list_lock 799 */ 800 struct dquot *dqget(struct super_block *sb, unsigned int id, int type) 801 { 802 unsigned int hashent = hashfn(sb, id, type); 803 struct dquot *dquot = NULL, *empty = NULL; 804 805 if (!sb_has_quota_active(sb, type)) 806 return NULL; 807 we_slept: 808 spin_lock(&dq_list_lock); 809 spin_lock(&dq_state_lock); 810 if (!sb_has_quota_active(sb, type)) { 811 spin_unlock(&dq_state_lock); 812 spin_unlock(&dq_list_lock); 813 goto out; 814 } 815 spin_unlock(&dq_state_lock); 816 817 dquot = find_dquot(hashent, sb, id, type); 818 if (!dquot) { 819 if (!empty) { 820 spin_unlock(&dq_list_lock); 821 empty = get_empty_dquot(sb, type); 822 if (!empty) 823 schedule(); /* Try to wait for a moment... */ 824 goto we_slept; 825 } 826 dquot = empty; 827 empty = NULL; 828 dquot->dq_id = id; 829 /* all dquots go on the inuse_list */ 830 put_inuse(dquot); 831 /* hash it first so it can be found */ 832 insert_dquot_hash(dquot); 833 spin_unlock(&dq_list_lock); 834 dqstats_inc(DQST_LOOKUPS); 835 } else { 836 if (!atomic_read(&dquot->dq_count)) 837 remove_free_dquot(dquot); 838 atomic_inc(&dquot->dq_count); 839 spin_unlock(&dq_list_lock); 840 dqstats_inc(DQST_CACHE_HITS); 841 dqstats_inc(DQST_LOOKUPS); 842 } 843 /* Wait for dq_lock - after this we know that either dquot_release() is 844 * already finished or it will be canceled due to dq_count > 1 test */ 845 wait_on_dquot(dquot); 846 /* Read the dquot / allocate space in quota file */ 847 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && 848 sb->dq_op->acquire_dquot(dquot) < 0) { 849 dqput(dquot); 850 dquot = NULL; 851 goto out; 852 } 853 #ifdef CONFIG_QUOTA_DEBUG 854 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ 855 #endif 856 out: 857 if (empty) 858 do_destroy_dquot(empty); 859 860 return dquot; 861 } 862 EXPORT_SYMBOL(dqget); 863 864 static int dqinit_needed(struct inode *inode, int type) 865 { 866 int cnt; 867 868 if (IS_NOQUOTA(inode)) 869 return 0; 870 if (type != -1) 871 return !inode->i_dquot[type]; 872 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 873 if (!inode->i_dquot[cnt]) 874 return 1; 875 return 0; 876 } 877 878 /* This routine is guarded by dqonoff_mutex mutex */ 879 static void add_dquot_ref(struct super_block *sb, int type) 880 { 881 struct inode *inode, *old_inode = NULL; 882 #ifdef CONFIG_QUOTA_DEBUG 883 int reserved = 0; 884 #endif 885 886 spin_lock(&inode_lock); 887 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 888 if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE|I_NEW)) 889 continue; 890 #ifdef CONFIG_QUOTA_DEBUG 891 if (unlikely(inode_get_rsv_space(inode) > 0)) 892 reserved = 1; 893 #endif 894 if (!atomic_read(&inode->i_writecount)) 895 continue; 896 if (!dqinit_needed(inode, type)) 897 continue; 898 899 __iget(inode); 900 spin_unlock(&inode_lock); 901 902 iput(old_inode); 903 __dquot_initialize(inode, type); 904 /* We hold a reference to 'inode' so it couldn't have been 905 * removed from s_inodes list while we dropped the inode_lock. 906 * We cannot iput the inode now as we can be holding the last 907 * reference and we cannot iput it under inode_lock. So we 908 * keep the reference and iput it later. */ 909 old_inode = inode; 910 spin_lock(&inode_lock); 911 } 912 spin_unlock(&inode_lock); 913 iput(old_inode); 914 915 #ifdef CONFIG_QUOTA_DEBUG 916 if (reserved) { 917 printk(KERN_WARNING "VFS (%s): Writes happened before quota" 918 " was turned on thus quota information is probably " 919 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 920 } 921 #endif 922 } 923 924 /* 925 * Return 0 if dqput() won't block. 926 * (note that 1 doesn't necessarily mean blocking) 927 */ 928 static inline int dqput_blocks(struct dquot *dquot) 929 { 930 if (atomic_read(&dquot->dq_count) <= 1) 931 return 1; 932 return 0; 933 } 934 935 /* 936 * Remove references to dquots from inode and add dquot to list for freeing 937 * if we have the last referece to dquot 938 * We can't race with anybody because we hold dqptr_sem for writing... 939 */ 940 static int remove_inode_dquot_ref(struct inode *inode, int type, 941 struct list_head *tofree_head) 942 { 943 struct dquot *dquot = inode->i_dquot[type]; 944 945 inode->i_dquot[type] = NULL; 946 if (dquot) { 947 if (dqput_blocks(dquot)) { 948 #ifdef CONFIG_QUOTA_DEBUG 949 if (atomic_read(&dquot->dq_count) != 1) 950 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count)); 951 #endif 952 spin_lock(&dq_list_lock); 953 /* As dquot must have currently users it can't be on 954 * the free list... */ 955 list_add(&dquot->dq_free, tofree_head); 956 spin_unlock(&dq_list_lock); 957 return 1; 958 } 959 else 960 dqput(dquot); /* We have guaranteed we won't block */ 961 } 962 return 0; 963 } 964 965 /* 966 * Free list of dquots 967 * Dquots are removed from inodes and no new references can be got so we are 968 * the only ones holding reference 969 */ 970 static void put_dquot_list(struct list_head *tofree_head) 971 { 972 struct list_head *act_head; 973 struct dquot *dquot; 974 975 act_head = tofree_head->next; 976 while (act_head != tofree_head) { 977 dquot = list_entry(act_head, struct dquot, dq_free); 978 act_head = act_head->next; 979 /* Remove dquot from the list so we won't have problems... */ 980 list_del_init(&dquot->dq_free); 981 dqput(dquot); 982 } 983 } 984 985 static void remove_dquot_ref(struct super_block *sb, int type, 986 struct list_head *tofree_head) 987 { 988 struct inode *inode; 989 990 spin_lock(&inode_lock); 991 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 992 /* 993 * We have to scan also I_NEW inodes because they can already 994 * have quota pointer initialized. Luckily, we need to touch 995 * only quota pointers and these have separate locking 996 * (dqptr_sem). 997 */ 998 if (!IS_NOQUOTA(inode)) 999 remove_inode_dquot_ref(inode, type, tofree_head); 1000 } 1001 spin_unlock(&inode_lock); 1002 } 1003 1004 /* Gather all references from inodes and drop them */ 1005 static void drop_dquot_ref(struct super_block *sb, int type) 1006 { 1007 LIST_HEAD(tofree_head); 1008 1009 if (sb->dq_op) { 1010 down_write(&sb_dqopt(sb)->dqptr_sem); 1011 remove_dquot_ref(sb, type, &tofree_head); 1012 up_write(&sb_dqopt(sb)->dqptr_sem); 1013 put_dquot_list(&tofree_head); 1014 } 1015 } 1016 1017 static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1018 { 1019 dquot->dq_dqb.dqb_curinodes += number; 1020 } 1021 1022 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1023 { 1024 dquot->dq_dqb.dqb_curspace += number; 1025 } 1026 1027 static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1028 { 1029 dquot->dq_dqb.dqb_rsvspace += number; 1030 } 1031 1032 /* 1033 * Claim reserved quota space 1034 */ 1035 static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1036 { 1037 if (dquot->dq_dqb.dqb_rsvspace < number) { 1038 WARN_ON_ONCE(1); 1039 number = dquot->dq_dqb.dqb_rsvspace; 1040 } 1041 dquot->dq_dqb.dqb_curspace += number; 1042 dquot->dq_dqb.dqb_rsvspace -= number; 1043 } 1044 1045 static inline 1046 void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1047 { 1048 if (dquot->dq_dqb.dqb_rsvspace >= number) 1049 dquot->dq_dqb.dqb_rsvspace -= number; 1050 else { 1051 WARN_ON_ONCE(1); 1052 dquot->dq_dqb.dqb_rsvspace = 0; 1053 } 1054 } 1055 1056 static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1057 { 1058 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1059 dquot->dq_dqb.dqb_curinodes >= number) 1060 dquot->dq_dqb.dqb_curinodes -= number; 1061 else 1062 dquot->dq_dqb.dqb_curinodes = 0; 1063 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1064 dquot->dq_dqb.dqb_itime = (time_t) 0; 1065 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1066 } 1067 1068 static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1069 { 1070 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1071 dquot->dq_dqb.dqb_curspace >= number) 1072 dquot->dq_dqb.dqb_curspace -= number; 1073 else 1074 dquot->dq_dqb.dqb_curspace = 0; 1075 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1076 dquot->dq_dqb.dqb_btime = (time_t) 0; 1077 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1078 } 1079 1080 static int warning_issued(struct dquot *dquot, const int warntype) 1081 { 1082 int flag = (warntype == QUOTA_NL_BHARDWARN || 1083 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1084 ((warntype == QUOTA_NL_IHARDWARN || 1085 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1086 1087 if (!flag) 1088 return 0; 1089 return test_and_set_bit(flag, &dquot->dq_flags); 1090 } 1091 1092 #ifdef CONFIG_PRINT_QUOTA_WARNING 1093 static int flag_print_warnings = 1; 1094 1095 static int need_print_warning(struct dquot *dquot) 1096 { 1097 if (!flag_print_warnings) 1098 return 0; 1099 1100 switch (dquot->dq_type) { 1101 case USRQUOTA: 1102 return current_fsuid() == dquot->dq_id; 1103 case GRPQUOTA: 1104 return in_group_p(dquot->dq_id); 1105 } 1106 return 0; 1107 } 1108 1109 /* Print warning to user which exceeded quota */ 1110 static void print_warning(struct dquot *dquot, const int warntype) 1111 { 1112 char *msg = NULL; 1113 struct tty_struct *tty; 1114 1115 if (warntype == QUOTA_NL_IHARDBELOW || 1116 warntype == QUOTA_NL_ISOFTBELOW || 1117 warntype == QUOTA_NL_BHARDBELOW || 1118 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot)) 1119 return; 1120 1121 tty = get_current_tty(); 1122 if (!tty) 1123 return; 1124 tty_write_message(tty, dquot->dq_sb->s_id); 1125 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1126 tty_write_message(tty, ": warning, "); 1127 else 1128 tty_write_message(tty, ": write failed, "); 1129 tty_write_message(tty, quotatypes[dquot->dq_type]); 1130 switch (warntype) { 1131 case QUOTA_NL_IHARDWARN: 1132 msg = " file limit reached.\r\n"; 1133 break; 1134 case QUOTA_NL_ISOFTLONGWARN: 1135 msg = " file quota exceeded too long.\r\n"; 1136 break; 1137 case QUOTA_NL_ISOFTWARN: 1138 msg = " file quota exceeded.\r\n"; 1139 break; 1140 case QUOTA_NL_BHARDWARN: 1141 msg = " block limit reached.\r\n"; 1142 break; 1143 case QUOTA_NL_BSOFTLONGWARN: 1144 msg = " block quota exceeded too long.\r\n"; 1145 break; 1146 case QUOTA_NL_BSOFTWARN: 1147 msg = " block quota exceeded.\r\n"; 1148 break; 1149 } 1150 tty_write_message(tty, msg); 1151 tty_kref_put(tty); 1152 } 1153 #endif 1154 1155 /* 1156 * Write warnings to the console and send warning messages over netlink. 1157 * 1158 * Note that this function can sleep. 1159 */ 1160 static void flush_warnings(struct dquot *const *dquots, char *warntype) 1161 { 1162 struct dquot *dq; 1163 int i; 1164 1165 for (i = 0; i < MAXQUOTAS; i++) { 1166 dq = dquots[i]; 1167 if (dq && warntype[i] != QUOTA_NL_NOWARN && 1168 !warning_issued(dq, warntype[i])) { 1169 #ifdef CONFIG_PRINT_QUOTA_WARNING 1170 print_warning(dq, warntype[i]); 1171 #endif 1172 quota_send_warning(dq->dq_type, dq->dq_id, 1173 dq->dq_sb->s_dev, warntype[i]); 1174 } 1175 } 1176 } 1177 1178 static int ignore_hardlimit(struct dquot *dquot) 1179 { 1180 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 1181 1182 return capable(CAP_SYS_RESOURCE) && 1183 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1184 !(info->dqi_flags & V1_DQF_RSQUASH)); 1185 } 1186 1187 /* needs dq_data_lock */ 1188 static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) 1189 { 1190 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1191 1192 *warntype = QUOTA_NL_NOWARN; 1193 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || 1194 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1195 return 0; 1196 1197 if (dquot->dq_dqb.dqb_ihardlimit && 1198 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1199 !ignore_hardlimit(dquot)) { 1200 *warntype = QUOTA_NL_IHARDWARN; 1201 return -EDQUOT; 1202 } 1203 1204 if (dquot->dq_dqb.dqb_isoftlimit && 1205 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1206 dquot->dq_dqb.dqb_itime && 1207 get_seconds() >= dquot->dq_dqb.dqb_itime && 1208 !ignore_hardlimit(dquot)) { 1209 *warntype = QUOTA_NL_ISOFTLONGWARN; 1210 return -EDQUOT; 1211 } 1212 1213 if (dquot->dq_dqb.dqb_isoftlimit && 1214 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1215 dquot->dq_dqb.dqb_itime == 0) { 1216 *warntype = QUOTA_NL_ISOFTWARN; 1217 dquot->dq_dqb.dqb_itime = get_seconds() + 1218 sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; 1219 } 1220 1221 return 0; 1222 } 1223 1224 /* needs dq_data_lock */ 1225 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) 1226 { 1227 qsize_t tspace; 1228 struct super_block *sb = dquot->dq_sb; 1229 1230 *warntype = QUOTA_NL_NOWARN; 1231 if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) || 1232 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1233 return 0; 1234 1235 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1236 + space; 1237 1238 if (dquot->dq_dqb.dqb_bhardlimit && 1239 tspace > dquot->dq_dqb.dqb_bhardlimit && 1240 !ignore_hardlimit(dquot)) { 1241 if (!prealloc) 1242 *warntype = QUOTA_NL_BHARDWARN; 1243 return -EDQUOT; 1244 } 1245 1246 if (dquot->dq_dqb.dqb_bsoftlimit && 1247 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1248 dquot->dq_dqb.dqb_btime && 1249 get_seconds() >= dquot->dq_dqb.dqb_btime && 1250 !ignore_hardlimit(dquot)) { 1251 if (!prealloc) 1252 *warntype = QUOTA_NL_BSOFTLONGWARN; 1253 return -EDQUOT; 1254 } 1255 1256 if (dquot->dq_dqb.dqb_bsoftlimit && 1257 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1258 dquot->dq_dqb.dqb_btime == 0) { 1259 if (!prealloc) { 1260 *warntype = QUOTA_NL_BSOFTWARN; 1261 dquot->dq_dqb.dqb_btime = get_seconds() + 1262 sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace; 1263 } 1264 else 1265 /* 1266 * We don't allow preallocation to exceed softlimit so exceeding will 1267 * be always printed 1268 */ 1269 return -EDQUOT; 1270 } 1271 1272 return 0; 1273 } 1274 1275 static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1276 { 1277 qsize_t newinodes; 1278 1279 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1280 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1281 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type)) 1282 return QUOTA_NL_NOWARN; 1283 1284 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1285 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1286 return QUOTA_NL_ISOFTBELOW; 1287 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1288 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1289 return QUOTA_NL_IHARDBELOW; 1290 return QUOTA_NL_NOWARN; 1291 } 1292 1293 static int info_bdq_free(struct dquot *dquot, qsize_t space) 1294 { 1295 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1296 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1297 return QUOTA_NL_NOWARN; 1298 1299 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1300 return QUOTA_NL_BSOFTBELOW; 1301 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1302 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1303 return QUOTA_NL_BHARDBELOW; 1304 return QUOTA_NL_NOWARN; 1305 } 1306 1307 /* 1308 * Initialize quota pointers in inode 1309 * 1310 * We do things in a bit complicated way but by that we avoid calling 1311 * dqget() and thus filesystem callbacks under dqptr_sem. 1312 * 1313 * It is better to call this function outside of any transaction as it 1314 * might need a lot of space in journal for dquot structure allocation. 1315 */ 1316 static void __dquot_initialize(struct inode *inode, int type) 1317 { 1318 unsigned int id = 0; 1319 int cnt; 1320 struct dquot *got[MAXQUOTAS]; 1321 struct super_block *sb = inode->i_sb; 1322 qsize_t rsv; 1323 1324 /* First test before acquiring mutex - solves deadlocks when we 1325 * re-enter the quota code and are already holding the mutex */ 1326 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1327 return; 1328 1329 /* First get references to structures we might need. */ 1330 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1331 got[cnt] = NULL; 1332 if (type != -1 && cnt != type) 1333 continue; 1334 switch (cnt) { 1335 case USRQUOTA: 1336 id = inode->i_uid; 1337 break; 1338 case GRPQUOTA: 1339 id = inode->i_gid; 1340 break; 1341 } 1342 got[cnt] = dqget(sb, id, cnt); 1343 } 1344 1345 down_write(&sb_dqopt(sb)->dqptr_sem); 1346 if (IS_NOQUOTA(inode)) 1347 goto out_err; 1348 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1349 if (type != -1 && cnt != type) 1350 continue; 1351 /* Avoid races with quotaoff() */ 1352 if (!sb_has_quota_active(sb, cnt)) 1353 continue; 1354 if (!inode->i_dquot[cnt]) { 1355 inode->i_dquot[cnt] = got[cnt]; 1356 got[cnt] = NULL; 1357 /* 1358 * Make quota reservation system happy if someone 1359 * did a write before quota was turned on 1360 */ 1361 rsv = inode_get_rsv_space(inode); 1362 if (unlikely(rsv)) 1363 dquot_resv_space(inode->i_dquot[cnt], rsv); 1364 } 1365 } 1366 out_err: 1367 up_write(&sb_dqopt(sb)->dqptr_sem); 1368 /* Drop unused references */ 1369 dqput_all(got); 1370 } 1371 1372 void dquot_initialize(struct inode *inode) 1373 { 1374 __dquot_initialize(inode, -1); 1375 } 1376 EXPORT_SYMBOL(dquot_initialize); 1377 1378 /* 1379 * Release all quotas referenced by inode 1380 */ 1381 static void __dquot_drop(struct inode *inode) 1382 { 1383 int cnt; 1384 struct dquot *put[MAXQUOTAS]; 1385 1386 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1387 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1388 put[cnt] = inode->i_dquot[cnt]; 1389 inode->i_dquot[cnt] = NULL; 1390 } 1391 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1392 dqput_all(put); 1393 } 1394 1395 void dquot_drop(struct inode *inode) 1396 { 1397 int cnt; 1398 1399 if (IS_NOQUOTA(inode)) 1400 return; 1401 1402 /* 1403 * Test before calling to rule out calls from proc and such 1404 * where we are not allowed to block. Note that this is 1405 * actually reliable test even without the lock - the caller 1406 * must assure that nobody can come after the DQUOT_DROP and 1407 * add quota pointers back anyway. 1408 */ 1409 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1410 if (inode->i_dquot[cnt]) 1411 break; 1412 } 1413 1414 if (cnt < MAXQUOTAS) 1415 __dquot_drop(inode); 1416 } 1417 EXPORT_SYMBOL(dquot_drop); 1418 1419 /* 1420 * inode_reserved_space is managed internally by quota, and protected by 1421 * i_lock similar to i_blocks+i_bytes. 1422 */ 1423 static qsize_t *inode_reserved_space(struct inode * inode) 1424 { 1425 /* Filesystem must explicitly define it's own method in order to use 1426 * quota reservation interface */ 1427 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1428 return inode->i_sb->dq_op->get_reserved_space(inode); 1429 } 1430 1431 void inode_add_rsv_space(struct inode *inode, qsize_t number) 1432 { 1433 spin_lock(&inode->i_lock); 1434 *inode_reserved_space(inode) += number; 1435 spin_unlock(&inode->i_lock); 1436 } 1437 EXPORT_SYMBOL(inode_add_rsv_space); 1438 1439 void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1440 { 1441 spin_lock(&inode->i_lock); 1442 *inode_reserved_space(inode) -= number; 1443 __inode_add_bytes(inode, number); 1444 spin_unlock(&inode->i_lock); 1445 } 1446 EXPORT_SYMBOL(inode_claim_rsv_space); 1447 1448 void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1449 { 1450 spin_lock(&inode->i_lock); 1451 *inode_reserved_space(inode) -= number; 1452 spin_unlock(&inode->i_lock); 1453 } 1454 EXPORT_SYMBOL(inode_sub_rsv_space); 1455 1456 static qsize_t inode_get_rsv_space(struct inode *inode) 1457 { 1458 qsize_t ret; 1459 1460 if (!inode->i_sb->dq_op->get_reserved_space) 1461 return 0; 1462 spin_lock(&inode->i_lock); 1463 ret = *inode_reserved_space(inode); 1464 spin_unlock(&inode->i_lock); 1465 return ret; 1466 } 1467 1468 static void inode_incr_space(struct inode *inode, qsize_t number, 1469 int reserve) 1470 { 1471 if (reserve) 1472 inode_add_rsv_space(inode, number); 1473 else 1474 inode_add_bytes(inode, number); 1475 } 1476 1477 static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1478 { 1479 if (reserve) 1480 inode_sub_rsv_space(inode, number); 1481 else 1482 inode_sub_bytes(inode, number); 1483 } 1484 1485 /* 1486 * This functions updates i_blocks+i_bytes fields and quota information 1487 * (together with appropriate checks). 1488 * 1489 * NOTE: We absolutely rely on the fact that caller dirties the inode 1490 * (usually helpers in quotaops.h care about this) and holds a handle for 1491 * the current transaction so that dquot write and inode write go into the 1492 * same transaction. 1493 */ 1494 1495 /* 1496 * This operation can block, but only after everything is updated 1497 */ 1498 int __dquot_alloc_space(struct inode *inode, qsize_t number, 1499 int warn, int reserve) 1500 { 1501 int cnt, ret = 0; 1502 char warntype[MAXQUOTAS]; 1503 1504 /* 1505 * First test before acquiring mutex - solves deadlocks when we 1506 * re-enter the quota code and are already holding the mutex 1507 */ 1508 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1509 inode_incr_space(inode, number, reserve); 1510 goto out; 1511 } 1512 1513 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1514 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1515 warntype[cnt] = QUOTA_NL_NOWARN; 1516 1517 spin_lock(&dq_data_lock); 1518 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1519 if (!inode->i_dquot[cnt]) 1520 continue; 1521 ret = check_bdq(inode->i_dquot[cnt], number, !warn, 1522 warntype+cnt); 1523 if (ret) { 1524 spin_unlock(&dq_data_lock); 1525 goto out_flush_warn; 1526 } 1527 } 1528 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1529 if (!inode->i_dquot[cnt]) 1530 continue; 1531 if (reserve) 1532 dquot_resv_space(inode->i_dquot[cnt], number); 1533 else 1534 dquot_incr_space(inode->i_dquot[cnt], number); 1535 } 1536 inode_incr_space(inode, number, reserve); 1537 spin_unlock(&dq_data_lock); 1538 1539 if (reserve) 1540 goto out_flush_warn; 1541 mark_all_dquot_dirty(inode->i_dquot); 1542 out_flush_warn: 1543 flush_warnings(inode->i_dquot, warntype); 1544 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1545 out: 1546 return ret; 1547 } 1548 EXPORT_SYMBOL(__dquot_alloc_space); 1549 1550 /* 1551 * This operation can block, but only after everything is updated 1552 */ 1553 int dquot_alloc_inode(const struct inode *inode) 1554 { 1555 int cnt, ret = 0; 1556 char warntype[MAXQUOTAS]; 1557 1558 /* First test before acquiring mutex - solves deadlocks when we 1559 * re-enter the quota code and are already holding the mutex */ 1560 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1561 return 0; 1562 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1563 warntype[cnt] = QUOTA_NL_NOWARN; 1564 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1565 spin_lock(&dq_data_lock); 1566 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1567 if (!inode->i_dquot[cnt]) 1568 continue; 1569 ret = check_idq(inode->i_dquot[cnt], 1, warntype + cnt); 1570 if (ret) 1571 goto warn_put_all; 1572 } 1573 1574 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1575 if (!inode->i_dquot[cnt]) 1576 continue; 1577 dquot_incr_inodes(inode->i_dquot[cnt], 1); 1578 } 1579 1580 warn_put_all: 1581 spin_unlock(&dq_data_lock); 1582 if (ret == 0) 1583 mark_all_dquot_dirty(inode->i_dquot); 1584 flush_warnings(inode->i_dquot, warntype); 1585 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1586 return ret; 1587 } 1588 EXPORT_SYMBOL(dquot_alloc_inode); 1589 1590 /* 1591 * Convert in-memory reserved quotas to real consumed quotas 1592 */ 1593 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1594 { 1595 int cnt; 1596 1597 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1598 inode_claim_rsv_space(inode, number); 1599 return 0; 1600 } 1601 1602 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1603 spin_lock(&dq_data_lock); 1604 /* Claim reserved quotas to allocated quotas */ 1605 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1606 if (inode->i_dquot[cnt]) 1607 dquot_claim_reserved_space(inode->i_dquot[cnt], 1608 number); 1609 } 1610 /* Update inode bytes */ 1611 inode_claim_rsv_space(inode, number); 1612 spin_unlock(&dq_data_lock); 1613 mark_all_dquot_dirty(inode->i_dquot); 1614 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1615 return 0; 1616 } 1617 EXPORT_SYMBOL(dquot_claim_space_nodirty); 1618 1619 /* 1620 * This operation can block, but only after everything is updated 1621 */ 1622 void __dquot_free_space(struct inode *inode, qsize_t number, int reserve) 1623 { 1624 unsigned int cnt; 1625 char warntype[MAXQUOTAS]; 1626 1627 /* First test before acquiring mutex - solves deadlocks when we 1628 * re-enter the quota code and are already holding the mutex */ 1629 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1630 inode_decr_space(inode, number, reserve); 1631 return; 1632 } 1633 1634 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1635 spin_lock(&dq_data_lock); 1636 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1637 if (!inode->i_dquot[cnt]) 1638 continue; 1639 warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number); 1640 if (reserve) 1641 dquot_free_reserved_space(inode->i_dquot[cnt], number); 1642 else 1643 dquot_decr_space(inode->i_dquot[cnt], number); 1644 } 1645 inode_decr_space(inode, number, reserve); 1646 spin_unlock(&dq_data_lock); 1647 1648 if (reserve) 1649 goto out_unlock; 1650 mark_all_dquot_dirty(inode->i_dquot); 1651 out_unlock: 1652 flush_warnings(inode->i_dquot, warntype); 1653 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1654 } 1655 EXPORT_SYMBOL(__dquot_free_space); 1656 1657 /* 1658 * This operation can block, but only after everything is updated 1659 */ 1660 void dquot_free_inode(const struct inode *inode) 1661 { 1662 unsigned int cnt; 1663 char warntype[MAXQUOTAS]; 1664 1665 /* First test before acquiring mutex - solves deadlocks when we 1666 * re-enter the quota code and are already holding the mutex */ 1667 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1668 return; 1669 1670 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1671 spin_lock(&dq_data_lock); 1672 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1673 if (!inode->i_dquot[cnt]) 1674 continue; 1675 warntype[cnt] = info_idq_free(inode->i_dquot[cnt], 1); 1676 dquot_decr_inodes(inode->i_dquot[cnt], 1); 1677 } 1678 spin_unlock(&dq_data_lock); 1679 mark_all_dquot_dirty(inode->i_dquot); 1680 flush_warnings(inode->i_dquot, warntype); 1681 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1682 } 1683 EXPORT_SYMBOL(dquot_free_inode); 1684 1685 /* 1686 * Transfer the number of inode and blocks from one diskquota to an other. 1687 * On success, dquot references in transfer_to are consumed and references 1688 * to original dquots that need to be released are placed there. On failure, 1689 * references are kept untouched. 1690 * 1691 * This operation can block, but only after everything is updated 1692 * A transaction must be started when entering this function. 1693 * 1694 */ 1695 int __dquot_transfer(struct inode *inode, struct dquot **transfer_to) 1696 { 1697 qsize_t space, cur_space; 1698 qsize_t rsv_space = 0; 1699 struct dquot *transfer_from[MAXQUOTAS] = {}; 1700 int cnt, ret = 0; 1701 char warntype_to[MAXQUOTAS]; 1702 char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS]; 1703 1704 /* First test before acquiring mutex - solves deadlocks when we 1705 * re-enter the quota code and are already holding the mutex */ 1706 if (IS_NOQUOTA(inode)) 1707 return 0; 1708 /* Initialize the arrays */ 1709 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1710 warntype_to[cnt] = QUOTA_NL_NOWARN; 1711 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1712 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1713 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1714 return 0; 1715 } 1716 spin_lock(&dq_data_lock); 1717 cur_space = inode_get_bytes(inode); 1718 rsv_space = inode_get_rsv_space(inode); 1719 space = cur_space + rsv_space; 1720 /* Build the transfer_from list and check the limits */ 1721 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1722 if (!transfer_to[cnt]) 1723 continue; 1724 transfer_from[cnt] = inode->i_dquot[cnt]; 1725 ret = check_idq(transfer_to[cnt], 1, warntype_to + cnt); 1726 if (ret) 1727 goto over_quota; 1728 ret = check_bdq(transfer_to[cnt], space, 0, warntype_to + cnt); 1729 if (ret) 1730 goto over_quota; 1731 } 1732 1733 /* 1734 * Finally perform the needed transfer from transfer_from to transfer_to 1735 */ 1736 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1737 /* 1738 * Skip changes for same uid or gid or for turned off quota-type. 1739 */ 1740 if (!transfer_to[cnt]) 1741 continue; 1742 1743 /* Due to IO error we might not have transfer_from[] structure */ 1744 if (transfer_from[cnt]) { 1745 warntype_from_inodes[cnt] = 1746 info_idq_free(transfer_from[cnt], 1); 1747 warntype_from_space[cnt] = 1748 info_bdq_free(transfer_from[cnt], space); 1749 dquot_decr_inodes(transfer_from[cnt], 1); 1750 dquot_decr_space(transfer_from[cnt], cur_space); 1751 dquot_free_reserved_space(transfer_from[cnt], 1752 rsv_space); 1753 } 1754 1755 dquot_incr_inodes(transfer_to[cnt], 1); 1756 dquot_incr_space(transfer_to[cnt], cur_space); 1757 dquot_resv_space(transfer_to[cnt], rsv_space); 1758 1759 inode->i_dquot[cnt] = transfer_to[cnt]; 1760 } 1761 spin_unlock(&dq_data_lock); 1762 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1763 1764 mark_all_dquot_dirty(transfer_from); 1765 mark_all_dquot_dirty(transfer_to); 1766 /* Pass back references to put */ 1767 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1768 transfer_to[cnt] = transfer_from[cnt]; 1769 warn: 1770 flush_warnings(transfer_to, warntype_to); 1771 flush_warnings(transfer_from, warntype_from_inodes); 1772 flush_warnings(transfer_from, warntype_from_space); 1773 return ret; 1774 over_quota: 1775 spin_unlock(&dq_data_lock); 1776 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1777 goto warn; 1778 } 1779 EXPORT_SYMBOL(__dquot_transfer); 1780 1781 /* Wrapper for transferring ownership of an inode for uid/gid only 1782 * Called from FSXXX_setattr() 1783 */ 1784 int dquot_transfer(struct inode *inode, struct iattr *iattr) 1785 { 1786 struct dquot *transfer_to[MAXQUOTAS] = {}; 1787 struct super_block *sb = inode->i_sb; 1788 int ret; 1789 1790 if (!sb_any_quota_active(sb) || IS_NOQUOTA(inode)) 1791 return 0; 1792 1793 if (iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) 1794 transfer_to[USRQUOTA] = dqget(sb, iattr->ia_uid, USRQUOTA); 1795 if (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid) 1796 transfer_to[GRPQUOTA] = dqget(sb, iattr->ia_gid, GRPQUOTA); 1797 1798 ret = __dquot_transfer(inode, transfer_to); 1799 dqput_all(transfer_to); 1800 return ret; 1801 } 1802 EXPORT_SYMBOL(dquot_transfer); 1803 1804 /* 1805 * Write info of quota file to disk 1806 */ 1807 int dquot_commit_info(struct super_block *sb, int type) 1808 { 1809 int ret; 1810 struct quota_info *dqopt = sb_dqopt(sb); 1811 1812 mutex_lock(&dqopt->dqio_mutex); 1813 ret = dqopt->ops[type]->write_file_info(sb, type); 1814 mutex_unlock(&dqopt->dqio_mutex); 1815 return ret; 1816 } 1817 EXPORT_SYMBOL(dquot_commit_info); 1818 1819 /* 1820 * Definitions of diskquota operations. 1821 */ 1822 const struct dquot_operations dquot_operations = { 1823 .write_dquot = dquot_commit, 1824 .acquire_dquot = dquot_acquire, 1825 .release_dquot = dquot_release, 1826 .mark_dirty = dquot_mark_dquot_dirty, 1827 .write_info = dquot_commit_info, 1828 .alloc_dquot = dquot_alloc, 1829 .destroy_dquot = dquot_destroy, 1830 }; 1831 EXPORT_SYMBOL(dquot_operations); 1832 1833 /* 1834 * Generic helper for ->open on filesystems supporting disk quotas. 1835 */ 1836 int dquot_file_open(struct inode *inode, struct file *file) 1837 { 1838 int error; 1839 1840 error = generic_file_open(inode, file); 1841 if (!error && (file->f_mode & FMODE_WRITE)) 1842 dquot_initialize(inode); 1843 return error; 1844 } 1845 EXPORT_SYMBOL(dquot_file_open); 1846 1847 /* 1848 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 1849 */ 1850 int dquot_disable(struct super_block *sb, int type, unsigned int flags) 1851 { 1852 int cnt, ret = 0; 1853 struct quota_info *dqopt = sb_dqopt(sb); 1854 struct inode *toputinode[MAXQUOTAS]; 1855 1856 /* Cannot turn off usage accounting without turning off limits, or 1857 * suspend quotas and simultaneously turn quotas off. */ 1858 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 1859 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 1860 DQUOT_USAGE_ENABLED))) 1861 return -EINVAL; 1862 1863 /* We need to serialize quota_off() for device */ 1864 mutex_lock(&dqopt->dqonoff_mutex); 1865 1866 /* 1867 * Skip everything if there's nothing to do. We have to do this because 1868 * sometimes we are called when fill_super() failed and calling 1869 * sync_fs() in such cases does no good. 1870 */ 1871 if (!sb_any_quota_loaded(sb)) { 1872 mutex_unlock(&dqopt->dqonoff_mutex); 1873 return 0; 1874 } 1875 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1876 toputinode[cnt] = NULL; 1877 if (type != -1 && cnt != type) 1878 continue; 1879 if (!sb_has_quota_loaded(sb, cnt)) 1880 continue; 1881 1882 if (flags & DQUOT_SUSPENDED) { 1883 spin_lock(&dq_state_lock); 1884 dqopt->flags |= 1885 dquot_state_flag(DQUOT_SUSPENDED, cnt); 1886 spin_unlock(&dq_state_lock); 1887 } else { 1888 spin_lock(&dq_state_lock); 1889 dqopt->flags &= ~dquot_state_flag(flags, cnt); 1890 /* Turning off suspended quotas? */ 1891 if (!sb_has_quota_loaded(sb, cnt) && 1892 sb_has_quota_suspended(sb, cnt)) { 1893 dqopt->flags &= ~dquot_state_flag( 1894 DQUOT_SUSPENDED, cnt); 1895 spin_unlock(&dq_state_lock); 1896 iput(dqopt->files[cnt]); 1897 dqopt->files[cnt] = NULL; 1898 continue; 1899 } 1900 spin_unlock(&dq_state_lock); 1901 } 1902 1903 /* We still have to keep quota loaded? */ 1904 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 1905 continue; 1906 1907 /* Note: these are blocking operations */ 1908 drop_dquot_ref(sb, cnt); 1909 invalidate_dquots(sb, cnt); 1910 /* 1911 * Now all dquots should be invalidated, all writes done so we 1912 * should be only users of the info. No locks needed. 1913 */ 1914 if (info_dirty(&dqopt->info[cnt])) 1915 sb->dq_op->write_info(sb, cnt); 1916 if (dqopt->ops[cnt]->free_file_info) 1917 dqopt->ops[cnt]->free_file_info(sb, cnt); 1918 put_quota_format(dqopt->info[cnt].dqi_format); 1919 1920 toputinode[cnt] = dqopt->files[cnt]; 1921 if (!sb_has_quota_loaded(sb, cnt)) 1922 dqopt->files[cnt] = NULL; 1923 dqopt->info[cnt].dqi_flags = 0; 1924 dqopt->info[cnt].dqi_igrace = 0; 1925 dqopt->info[cnt].dqi_bgrace = 0; 1926 dqopt->ops[cnt] = NULL; 1927 } 1928 mutex_unlock(&dqopt->dqonoff_mutex); 1929 1930 /* Skip syncing and setting flags if quota files are hidden */ 1931 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 1932 goto put_inodes; 1933 1934 /* Sync the superblock so that buffers with quota data are written to 1935 * disk (and so userspace sees correct data afterwards). */ 1936 if (sb->s_op->sync_fs) 1937 sb->s_op->sync_fs(sb, 1); 1938 sync_blockdev(sb->s_bdev); 1939 /* Now the quota files are just ordinary files and we can set the 1940 * inode flags back. Moreover we discard the pagecache so that 1941 * userspace sees the writes we did bypassing the pagecache. We 1942 * must also discard the blockdev buffers so that we see the 1943 * changes done by userspace on the next quotaon() */ 1944 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1945 if (toputinode[cnt]) { 1946 mutex_lock(&dqopt->dqonoff_mutex); 1947 /* If quota was reenabled in the meantime, we have 1948 * nothing to do */ 1949 if (!sb_has_quota_loaded(sb, cnt)) { 1950 mutex_lock_nested(&toputinode[cnt]->i_mutex, 1951 I_MUTEX_QUOTA); 1952 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 1953 S_NOATIME | S_NOQUOTA); 1954 truncate_inode_pages(&toputinode[cnt]->i_data, 1955 0); 1956 mutex_unlock(&toputinode[cnt]->i_mutex); 1957 mark_inode_dirty(toputinode[cnt]); 1958 } 1959 mutex_unlock(&dqopt->dqonoff_mutex); 1960 } 1961 if (sb->s_bdev) 1962 invalidate_bdev(sb->s_bdev); 1963 put_inodes: 1964 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1965 if (toputinode[cnt]) { 1966 /* On remount RO, we keep the inode pointer so that we 1967 * can reenable quota on the subsequent remount RW. We 1968 * have to check 'flags' variable and not use sb_has_ 1969 * function because another quotaon / quotaoff could 1970 * change global state before we got here. We refuse 1971 * to suspend quotas when there is pending delete on 1972 * the quota file... */ 1973 if (!(flags & DQUOT_SUSPENDED)) 1974 iput(toputinode[cnt]); 1975 else if (!toputinode[cnt]->i_nlink) 1976 ret = -EBUSY; 1977 } 1978 return ret; 1979 } 1980 EXPORT_SYMBOL(dquot_disable); 1981 1982 int dquot_quota_off(struct super_block *sb, int type) 1983 { 1984 return dquot_disable(sb, type, 1985 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 1986 } 1987 EXPORT_SYMBOL(dquot_quota_off); 1988 1989 /* 1990 * Turn quotas on on a device 1991 */ 1992 1993 /* 1994 * Helper function to turn quotas on when we already have the inode of 1995 * quota file and no quota information is loaded. 1996 */ 1997 static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 1998 unsigned int flags) 1999 { 2000 struct quota_format_type *fmt = find_quota_format(format_id); 2001 struct super_block *sb = inode->i_sb; 2002 struct quota_info *dqopt = sb_dqopt(sb); 2003 int error; 2004 int oldflags = -1; 2005 2006 if (!fmt) 2007 return -ESRCH; 2008 if (!S_ISREG(inode->i_mode)) { 2009 error = -EACCES; 2010 goto out_fmt; 2011 } 2012 if (IS_RDONLY(inode)) { 2013 error = -EROFS; 2014 goto out_fmt; 2015 } 2016 if (!sb->s_op->quota_write || !sb->s_op->quota_read) { 2017 error = -EINVAL; 2018 goto out_fmt; 2019 } 2020 /* Usage always has to be set... */ 2021 if (!(flags & DQUOT_USAGE_ENABLED)) { 2022 error = -EINVAL; 2023 goto out_fmt; 2024 } 2025 2026 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2027 /* As we bypass the pagecache we must now flush all the 2028 * dirty data and invalidate caches so that kernel sees 2029 * changes from userspace. It is not enough to just flush 2030 * the quota file since if blocksize < pagesize, invalidation 2031 * of the cache could fail because of other unrelated dirty 2032 * data */ 2033 sync_filesystem(sb); 2034 invalidate_bdev(sb->s_bdev); 2035 } 2036 mutex_lock(&dqopt->dqonoff_mutex); 2037 if (sb_has_quota_loaded(sb, type)) { 2038 error = -EBUSY; 2039 goto out_lock; 2040 } 2041 2042 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2043 /* We don't want quota and atime on quota files (deadlocks 2044 * possible) Also nobody should write to the file - we use 2045 * special IO operations which ignore the immutable bit. */ 2046 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2047 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2048 S_NOQUOTA); 2049 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2050 mutex_unlock(&inode->i_mutex); 2051 /* 2052 * When S_NOQUOTA is set, remove dquot references as no more 2053 * references can be added 2054 */ 2055 __dquot_drop(inode); 2056 } 2057 2058 error = -EIO; 2059 dqopt->files[type] = igrab(inode); 2060 if (!dqopt->files[type]) 2061 goto out_lock; 2062 error = -EINVAL; 2063 if (!fmt->qf_ops->check_quota_file(sb, type)) 2064 goto out_file_init; 2065 2066 dqopt->ops[type] = fmt->qf_ops; 2067 dqopt->info[type].dqi_format = fmt; 2068 dqopt->info[type].dqi_fmt_id = format_id; 2069 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2070 mutex_lock(&dqopt->dqio_mutex); 2071 error = dqopt->ops[type]->read_file_info(sb, type); 2072 if (error < 0) { 2073 mutex_unlock(&dqopt->dqio_mutex); 2074 goto out_file_init; 2075 } 2076 mutex_unlock(&dqopt->dqio_mutex); 2077 spin_lock(&dq_state_lock); 2078 dqopt->flags |= dquot_state_flag(flags, type); 2079 spin_unlock(&dq_state_lock); 2080 2081 add_dquot_ref(sb, type); 2082 mutex_unlock(&dqopt->dqonoff_mutex); 2083 2084 return 0; 2085 2086 out_file_init: 2087 dqopt->files[type] = NULL; 2088 iput(inode); 2089 out_lock: 2090 if (oldflags != -1) { 2091 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2092 /* Set the flags back (in the case of accidental quotaon() 2093 * on a wrong file we don't want to mess up the flags) */ 2094 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2095 inode->i_flags |= oldflags; 2096 mutex_unlock(&inode->i_mutex); 2097 } 2098 mutex_unlock(&dqopt->dqonoff_mutex); 2099 out_fmt: 2100 put_quota_format(fmt); 2101 2102 return error; 2103 } 2104 2105 /* Reenable quotas on remount RW */ 2106 int dquot_resume(struct super_block *sb, int type) 2107 { 2108 struct quota_info *dqopt = sb_dqopt(sb); 2109 struct inode *inode; 2110 int ret = 0, cnt; 2111 unsigned int flags; 2112 2113 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2114 if (type != -1 && cnt != type) 2115 continue; 2116 2117 mutex_lock(&dqopt->dqonoff_mutex); 2118 if (!sb_has_quota_suspended(sb, cnt)) { 2119 mutex_unlock(&dqopt->dqonoff_mutex); 2120 continue; 2121 } 2122 inode = dqopt->files[cnt]; 2123 dqopt->files[cnt] = NULL; 2124 spin_lock(&dq_state_lock); 2125 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2126 DQUOT_LIMITS_ENABLED, 2127 cnt); 2128 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt); 2129 spin_unlock(&dq_state_lock); 2130 mutex_unlock(&dqopt->dqonoff_mutex); 2131 2132 flags = dquot_generic_flag(flags, cnt); 2133 ret = vfs_load_quota_inode(inode, cnt, 2134 dqopt->info[cnt].dqi_fmt_id, flags); 2135 iput(inode); 2136 } 2137 2138 return ret; 2139 } 2140 EXPORT_SYMBOL(dquot_resume); 2141 2142 int dquot_quota_on_path(struct super_block *sb, int type, int format_id, 2143 struct path *path) 2144 { 2145 int error = security_quota_on(path->dentry); 2146 if (error) 2147 return error; 2148 /* Quota file not on the same filesystem? */ 2149 if (path->mnt->mnt_sb != sb) 2150 error = -EXDEV; 2151 else 2152 error = vfs_load_quota_inode(path->dentry->d_inode, type, 2153 format_id, DQUOT_USAGE_ENABLED | 2154 DQUOT_LIMITS_ENABLED); 2155 return error; 2156 } 2157 EXPORT_SYMBOL(dquot_quota_on_path); 2158 2159 int dquot_quota_on(struct super_block *sb, int type, int format_id, char *name) 2160 { 2161 struct path path; 2162 int error; 2163 2164 error = kern_path(name, LOOKUP_FOLLOW, &path); 2165 if (!error) { 2166 error = dquot_quota_on_path(sb, type, format_id, &path); 2167 path_put(&path); 2168 } 2169 return error; 2170 } 2171 EXPORT_SYMBOL(dquot_quota_on); 2172 2173 /* 2174 * More powerful function for turning on quotas allowing setting 2175 * of individual quota flags 2176 */ 2177 int dquot_enable(struct inode *inode, int type, int format_id, 2178 unsigned int flags) 2179 { 2180 int ret = 0; 2181 struct super_block *sb = inode->i_sb; 2182 struct quota_info *dqopt = sb_dqopt(sb); 2183 2184 /* Just unsuspend quotas? */ 2185 BUG_ON(flags & DQUOT_SUSPENDED); 2186 2187 if (!flags) 2188 return 0; 2189 /* Just updating flags needed? */ 2190 if (sb_has_quota_loaded(sb, type)) { 2191 mutex_lock(&dqopt->dqonoff_mutex); 2192 /* Now do a reliable test... */ 2193 if (!sb_has_quota_loaded(sb, type)) { 2194 mutex_unlock(&dqopt->dqonoff_mutex); 2195 goto load_quota; 2196 } 2197 if (flags & DQUOT_USAGE_ENABLED && 2198 sb_has_quota_usage_enabled(sb, type)) { 2199 ret = -EBUSY; 2200 goto out_lock; 2201 } 2202 if (flags & DQUOT_LIMITS_ENABLED && 2203 sb_has_quota_limits_enabled(sb, type)) { 2204 ret = -EBUSY; 2205 goto out_lock; 2206 } 2207 spin_lock(&dq_state_lock); 2208 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2209 spin_unlock(&dq_state_lock); 2210 out_lock: 2211 mutex_unlock(&dqopt->dqonoff_mutex); 2212 return ret; 2213 } 2214 2215 load_quota: 2216 return vfs_load_quota_inode(inode, type, format_id, flags); 2217 } 2218 EXPORT_SYMBOL(dquot_enable); 2219 2220 /* 2221 * This function is used when filesystem needs to initialize quotas 2222 * during mount time. 2223 */ 2224 int dquot_quota_on_mount(struct super_block *sb, char *qf_name, 2225 int format_id, int type) 2226 { 2227 struct dentry *dentry; 2228 int error; 2229 2230 mutex_lock(&sb->s_root->d_inode->i_mutex); 2231 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2232 mutex_unlock(&sb->s_root->d_inode->i_mutex); 2233 if (IS_ERR(dentry)) 2234 return PTR_ERR(dentry); 2235 2236 if (!dentry->d_inode) { 2237 error = -ENOENT; 2238 goto out; 2239 } 2240 2241 error = security_quota_on(dentry); 2242 if (!error) 2243 error = vfs_load_quota_inode(dentry->d_inode, type, format_id, 2244 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2245 2246 out: 2247 dput(dentry); 2248 return error; 2249 } 2250 EXPORT_SYMBOL(dquot_quota_on_mount); 2251 2252 static inline qsize_t qbtos(qsize_t blocks) 2253 { 2254 return blocks << QIF_DQBLKSIZE_BITS; 2255 } 2256 2257 static inline qsize_t stoqb(qsize_t space) 2258 { 2259 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; 2260 } 2261 2262 /* Generic routine for getting common part of quota structure */ 2263 static void do_get_dqblk(struct dquot *dquot, struct fs_disk_quota *di) 2264 { 2265 struct mem_dqblk *dm = &dquot->dq_dqb; 2266 2267 memset(di, 0, sizeof(*di)); 2268 di->d_version = FS_DQUOT_VERSION; 2269 di->d_flags = dquot->dq_type == USRQUOTA ? 2270 XFS_USER_QUOTA : XFS_GROUP_QUOTA; 2271 di->d_id = dquot->dq_id; 2272 2273 spin_lock(&dq_data_lock); 2274 di->d_blk_hardlimit = stoqb(dm->dqb_bhardlimit); 2275 di->d_blk_softlimit = stoqb(dm->dqb_bsoftlimit); 2276 di->d_ino_hardlimit = dm->dqb_ihardlimit; 2277 di->d_ino_softlimit = dm->dqb_isoftlimit; 2278 di->d_bcount = dm->dqb_curspace + dm->dqb_rsvspace; 2279 di->d_icount = dm->dqb_curinodes; 2280 di->d_btimer = dm->dqb_btime; 2281 di->d_itimer = dm->dqb_itime; 2282 spin_unlock(&dq_data_lock); 2283 } 2284 2285 int dquot_get_dqblk(struct super_block *sb, int type, qid_t id, 2286 struct fs_disk_quota *di) 2287 { 2288 struct dquot *dquot; 2289 2290 dquot = dqget(sb, id, type); 2291 if (!dquot) 2292 return -ESRCH; 2293 do_get_dqblk(dquot, di); 2294 dqput(dquot); 2295 2296 return 0; 2297 } 2298 EXPORT_SYMBOL(dquot_get_dqblk); 2299 2300 #define VFS_FS_DQ_MASK \ 2301 (FS_DQ_BCOUNT | FS_DQ_BSOFT | FS_DQ_BHARD | \ 2302 FS_DQ_ICOUNT | FS_DQ_ISOFT | FS_DQ_IHARD | \ 2303 FS_DQ_BTIMER | FS_DQ_ITIMER) 2304 2305 /* Generic routine for setting common part of quota structure */ 2306 static int do_set_dqblk(struct dquot *dquot, struct fs_disk_quota *di) 2307 { 2308 struct mem_dqblk *dm = &dquot->dq_dqb; 2309 int check_blim = 0, check_ilim = 0; 2310 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 2311 2312 if (di->d_fieldmask & ~VFS_FS_DQ_MASK) 2313 return -EINVAL; 2314 2315 if (((di->d_fieldmask & FS_DQ_BSOFT) && 2316 (di->d_blk_softlimit > dqi->dqi_maxblimit)) || 2317 ((di->d_fieldmask & FS_DQ_BHARD) && 2318 (di->d_blk_hardlimit > dqi->dqi_maxblimit)) || 2319 ((di->d_fieldmask & FS_DQ_ISOFT) && 2320 (di->d_ino_softlimit > dqi->dqi_maxilimit)) || 2321 ((di->d_fieldmask & FS_DQ_IHARD) && 2322 (di->d_ino_hardlimit > dqi->dqi_maxilimit))) 2323 return -ERANGE; 2324 2325 spin_lock(&dq_data_lock); 2326 if (di->d_fieldmask & FS_DQ_BCOUNT) { 2327 dm->dqb_curspace = di->d_bcount - dm->dqb_rsvspace; 2328 check_blim = 1; 2329 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2330 } 2331 2332 if (di->d_fieldmask & FS_DQ_BSOFT) 2333 dm->dqb_bsoftlimit = qbtos(di->d_blk_softlimit); 2334 if (di->d_fieldmask & FS_DQ_BHARD) 2335 dm->dqb_bhardlimit = qbtos(di->d_blk_hardlimit); 2336 if (di->d_fieldmask & (FS_DQ_BSOFT | FS_DQ_BHARD)) { 2337 check_blim = 1; 2338 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2339 } 2340 2341 if (di->d_fieldmask & FS_DQ_ICOUNT) { 2342 dm->dqb_curinodes = di->d_icount; 2343 check_ilim = 1; 2344 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2345 } 2346 2347 if (di->d_fieldmask & FS_DQ_ISOFT) 2348 dm->dqb_isoftlimit = di->d_ino_softlimit; 2349 if (di->d_fieldmask & FS_DQ_IHARD) 2350 dm->dqb_ihardlimit = di->d_ino_hardlimit; 2351 if (di->d_fieldmask & (FS_DQ_ISOFT | FS_DQ_IHARD)) { 2352 check_ilim = 1; 2353 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2354 } 2355 2356 if (di->d_fieldmask & FS_DQ_BTIMER) { 2357 dm->dqb_btime = di->d_btimer; 2358 check_blim = 1; 2359 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2360 } 2361 2362 if (di->d_fieldmask & FS_DQ_ITIMER) { 2363 dm->dqb_itime = di->d_itimer; 2364 check_ilim = 1; 2365 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2366 } 2367 2368 if (check_blim) { 2369 if (!dm->dqb_bsoftlimit || 2370 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2371 dm->dqb_btime = 0; 2372 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2373 } else if (!(di->d_fieldmask & FS_DQ_BTIMER)) 2374 /* Set grace only if user hasn't provided his own... */ 2375 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2376 } 2377 if (check_ilim) { 2378 if (!dm->dqb_isoftlimit || 2379 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2380 dm->dqb_itime = 0; 2381 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2382 } else if (!(di->d_fieldmask & FS_DQ_ITIMER)) 2383 /* Set grace only if user hasn't provided his own... */ 2384 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2385 } 2386 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2387 dm->dqb_isoftlimit) 2388 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2389 else 2390 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2391 spin_unlock(&dq_data_lock); 2392 mark_dquot_dirty(dquot); 2393 2394 return 0; 2395 } 2396 2397 int dquot_set_dqblk(struct super_block *sb, int type, qid_t id, 2398 struct fs_disk_quota *di) 2399 { 2400 struct dquot *dquot; 2401 int rc; 2402 2403 dquot = dqget(sb, id, type); 2404 if (!dquot) { 2405 rc = -ESRCH; 2406 goto out; 2407 } 2408 rc = do_set_dqblk(dquot, di); 2409 dqput(dquot); 2410 out: 2411 return rc; 2412 } 2413 EXPORT_SYMBOL(dquot_set_dqblk); 2414 2415 /* Generic routine for getting common part of quota file information */ 2416 int dquot_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2417 { 2418 struct mem_dqinfo *mi; 2419 2420 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2421 if (!sb_has_quota_active(sb, type)) { 2422 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2423 return -ESRCH; 2424 } 2425 mi = sb_dqopt(sb)->info + type; 2426 spin_lock(&dq_data_lock); 2427 ii->dqi_bgrace = mi->dqi_bgrace; 2428 ii->dqi_igrace = mi->dqi_igrace; 2429 ii->dqi_flags = mi->dqi_flags & DQF_MASK; 2430 ii->dqi_valid = IIF_ALL; 2431 spin_unlock(&dq_data_lock); 2432 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2433 return 0; 2434 } 2435 EXPORT_SYMBOL(dquot_get_dqinfo); 2436 2437 /* Generic routine for setting common part of quota file information */ 2438 int dquot_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2439 { 2440 struct mem_dqinfo *mi; 2441 int err = 0; 2442 2443 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2444 if (!sb_has_quota_active(sb, type)) { 2445 err = -ESRCH; 2446 goto out; 2447 } 2448 mi = sb_dqopt(sb)->info + type; 2449 spin_lock(&dq_data_lock); 2450 if (ii->dqi_valid & IIF_BGRACE) 2451 mi->dqi_bgrace = ii->dqi_bgrace; 2452 if (ii->dqi_valid & IIF_IGRACE) 2453 mi->dqi_igrace = ii->dqi_igrace; 2454 if (ii->dqi_valid & IIF_FLAGS) 2455 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | 2456 (ii->dqi_flags & DQF_MASK); 2457 spin_unlock(&dq_data_lock); 2458 mark_info_dirty(sb, type); 2459 /* Force write to disk */ 2460 sb->dq_op->write_info(sb, type); 2461 out: 2462 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2463 return err; 2464 } 2465 EXPORT_SYMBOL(dquot_set_dqinfo); 2466 2467 const struct quotactl_ops dquot_quotactl_ops = { 2468 .quota_on = dquot_quota_on, 2469 .quota_off = dquot_quota_off, 2470 .quota_sync = dquot_quota_sync, 2471 .get_info = dquot_get_dqinfo, 2472 .set_info = dquot_set_dqinfo, 2473 .get_dqblk = dquot_get_dqblk, 2474 .set_dqblk = dquot_set_dqblk 2475 }; 2476 EXPORT_SYMBOL(dquot_quotactl_ops); 2477 2478 static int do_proc_dqstats(struct ctl_table *table, int write, 2479 void __user *buffer, size_t *lenp, loff_t *ppos) 2480 { 2481 unsigned int type = (int *)table->data - dqstats.stat; 2482 2483 /* Update global table */ 2484 dqstats.stat[type] = 2485 percpu_counter_sum_positive(&dqstats.counter[type]); 2486 return proc_dointvec(table, write, buffer, lenp, ppos); 2487 } 2488 2489 static ctl_table fs_dqstats_table[] = { 2490 { 2491 .procname = "lookups", 2492 .data = &dqstats.stat[DQST_LOOKUPS], 2493 .maxlen = sizeof(int), 2494 .mode = 0444, 2495 .proc_handler = do_proc_dqstats, 2496 }, 2497 { 2498 .procname = "drops", 2499 .data = &dqstats.stat[DQST_DROPS], 2500 .maxlen = sizeof(int), 2501 .mode = 0444, 2502 .proc_handler = do_proc_dqstats, 2503 }, 2504 { 2505 .procname = "reads", 2506 .data = &dqstats.stat[DQST_READS], 2507 .maxlen = sizeof(int), 2508 .mode = 0444, 2509 .proc_handler = do_proc_dqstats, 2510 }, 2511 { 2512 .procname = "writes", 2513 .data = &dqstats.stat[DQST_WRITES], 2514 .maxlen = sizeof(int), 2515 .mode = 0444, 2516 .proc_handler = do_proc_dqstats, 2517 }, 2518 { 2519 .procname = "cache_hits", 2520 .data = &dqstats.stat[DQST_CACHE_HITS], 2521 .maxlen = sizeof(int), 2522 .mode = 0444, 2523 .proc_handler = do_proc_dqstats, 2524 }, 2525 { 2526 .procname = "allocated_dquots", 2527 .data = &dqstats.stat[DQST_ALLOC_DQUOTS], 2528 .maxlen = sizeof(int), 2529 .mode = 0444, 2530 .proc_handler = do_proc_dqstats, 2531 }, 2532 { 2533 .procname = "free_dquots", 2534 .data = &dqstats.stat[DQST_FREE_DQUOTS], 2535 .maxlen = sizeof(int), 2536 .mode = 0444, 2537 .proc_handler = do_proc_dqstats, 2538 }, 2539 { 2540 .procname = "syncs", 2541 .data = &dqstats.stat[DQST_SYNCS], 2542 .maxlen = sizeof(int), 2543 .mode = 0444, 2544 .proc_handler = do_proc_dqstats, 2545 }, 2546 #ifdef CONFIG_PRINT_QUOTA_WARNING 2547 { 2548 .procname = "warnings", 2549 .data = &flag_print_warnings, 2550 .maxlen = sizeof(int), 2551 .mode = 0644, 2552 .proc_handler = proc_dointvec, 2553 }, 2554 #endif 2555 { }, 2556 }; 2557 2558 static ctl_table fs_table[] = { 2559 { 2560 .procname = "quota", 2561 .mode = 0555, 2562 .child = fs_dqstats_table, 2563 }, 2564 { }, 2565 }; 2566 2567 static ctl_table sys_table[] = { 2568 { 2569 .procname = "fs", 2570 .mode = 0555, 2571 .child = fs_table, 2572 }, 2573 { }, 2574 }; 2575 2576 static int __init dquot_init(void) 2577 { 2578 int i, ret; 2579 unsigned long nr_hash, order; 2580 2581 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2582 2583 register_sysctl_table(sys_table); 2584 2585 dquot_cachep = kmem_cache_create("dquot", 2586 sizeof(struct dquot), sizeof(unsigned long) * 4, 2587 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2588 SLAB_MEM_SPREAD|SLAB_PANIC), 2589 NULL); 2590 2591 order = 0; 2592 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2593 if (!dquot_hash) 2594 panic("Cannot create dquot hash table"); 2595 2596 for (i = 0; i < _DQST_DQSTAT_LAST; i++) { 2597 ret = percpu_counter_init(&dqstats.counter[i], 0); 2598 if (ret) 2599 panic("Cannot create dquot stat counters"); 2600 } 2601 2602 /* Find power-of-two hlist_heads which can fit into allocation */ 2603 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2604 dq_hash_bits = 0; 2605 do { 2606 dq_hash_bits++; 2607 } while (nr_hash >> dq_hash_bits); 2608 dq_hash_bits--; 2609 2610 nr_hash = 1UL << dq_hash_bits; 2611 dq_hash_mask = nr_hash - 1; 2612 for (i = 0; i < nr_hash; i++) 2613 INIT_HLIST_HEAD(dquot_hash + i); 2614 2615 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", 2616 nr_hash, order, (PAGE_SIZE << order)); 2617 2618 register_shrinker(&dqcache_shrinker); 2619 2620 return 0; 2621 } 2622 module_init(dquot_init); 2623