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 #ifdef CONFIG_SMP 232 struct dqstats *dqstats_pcpu; 233 EXPORT_SYMBOL(dqstats_pcpu); 234 #endif 235 236 static qsize_t inode_get_rsv_space(struct inode *inode); 237 static void __dquot_initialize(struct inode *inode, int type); 238 239 static inline unsigned int 240 hashfn(const struct super_block *sb, unsigned int id, int type) 241 { 242 unsigned long tmp; 243 244 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type); 245 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask; 246 } 247 248 /* 249 * Following list functions expect dq_list_lock to be held 250 */ 251 static inline void insert_dquot_hash(struct dquot *dquot) 252 { 253 struct hlist_head *head; 254 head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type); 255 hlist_add_head(&dquot->dq_hash, head); 256 } 257 258 static inline void remove_dquot_hash(struct dquot *dquot) 259 { 260 hlist_del_init(&dquot->dq_hash); 261 } 262 263 static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, 264 unsigned int id, int type) 265 { 266 struct hlist_node *node; 267 struct dquot *dquot; 268 269 hlist_for_each (node, dquot_hash+hashent) { 270 dquot = hlist_entry(node, struct dquot, dq_hash); 271 if (dquot->dq_sb == sb && dquot->dq_id == id && 272 dquot->dq_type == type) 273 return dquot; 274 } 275 return NULL; 276 } 277 278 /* Add a dquot to the tail of the free list */ 279 static inline void put_dquot_last(struct dquot *dquot) 280 { 281 list_add_tail(&dquot->dq_free, &free_dquots); 282 dqstats_inc(DQST_FREE_DQUOTS); 283 } 284 285 static inline void remove_free_dquot(struct dquot *dquot) 286 { 287 if (list_empty(&dquot->dq_free)) 288 return; 289 list_del_init(&dquot->dq_free); 290 dqstats_dec(DQST_FREE_DQUOTS); 291 } 292 293 static inline void put_inuse(struct dquot *dquot) 294 { 295 /* We add to the back of inuse list so we don't have to restart 296 * when traversing this list and we block */ 297 list_add_tail(&dquot->dq_inuse, &inuse_list); 298 dqstats_inc(DQST_ALLOC_DQUOTS); 299 } 300 301 static inline void remove_inuse(struct dquot *dquot) 302 { 303 dqstats_dec(DQST_ALLOC_DQUOTS); 304 list_del(&dquot->dq_inuse); 305 } 306 /* 307 * End of list functions needing dq_list_lock 308 */ 309 310 static void wait_on_dquot(struct dquot *dquot) 311 { 312 mutex_lock(&dquot->dq_lock); 313 mutex_unlock(&dquot->dq_lock); 314 } 315 316 static inline int dquot_dirty(struct dquot *dquot) 317 { 318 return test_bit(DQ_MOD_B, &dquot->dq_flags); 319 } 320 321 static inline int mark_dquot_dirty(struct dquot *dquot) 322 { 323 return dquot->dq_sb->dq_op->mark_dirty(dquot); 324 } 325 326 /* Mark dquot dirty in atomic manner, and return it's old dirty flag state */ 327 int dquot_mark_dquot_dirty(struct dquot *dquot) 328 { 329 int ret = 1; 330 331 /* If quota is dirty already, we don't have to acquire dq_list_lock */ 332 if (test_bit(DQ_MOD_B, &dquot->dq_flags)) 333 return 1; 334 335 spin_lock(&dq_list_lock); 336 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) { 337 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)-> 338 info[dquot->dq_type].dqi_dirty_list); 339 ret = 0; 340 } 341 spin_unlock(&dq_list_lock); 342 return ret; 343 } 344 EXPORT_SYMBOL(dquot_mark_dquot_dirty); 345 346 /* Dirtify all the dquots - this can block when journalling */ 347 static inline int mark_all_dquot_dirty(struct dquot * const *dquot) 348 { 349 int ret, err, cnt; 350 351 ret = err = 0; 352 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 353 if (dquot[cnt]) 354 /* Even in case of error we have to continue */ 355 ret = mark_dquot_dirty(dquot[cnt]); 356 if (!err) 357 err = ret; 358 } 359 return err; 360 } 361 362 static inline void dqput_all(struct dquot **dquot) 363 { 364 unsigned int cnt; 365 366 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 367 dqput(dquot[cnt]); 368 } 369 370 /* This function needs dq_list_lock */ 371 static inline int clear_dquot_dirty(struct dquot *dquot) 372 { 373 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) 374 return 0; 375 list_del_init(&dquot->dq_dirty); 376 return 1; 377 } 378 379 void mark_info_dirty(struct super_block *sb, int type) 380 { 381 set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags); 382 } 383 EXPORT_SYMBOL(mark_info_dirty); 384 385 /* 386 * Read dquot from disk and alloc space for it 387 */ 388 389 int dquot_acquire(struct dquot *dquot) 390 { 391 int ret = 0, ret2 = 0; 392 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 393 394 mutex_lock(&dquot->dq_lock); 395 mutex_lock(&dqopt->dqio_mutex); 396 if (!test_bit(DQ_READ_B, &dquot->dq_flags)) 397 ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot); 398 if (ret < 0) 399 goto out_iolock; 400 set_bit(DQ_READ_B, &dquot->dq_flags); 401 /* Instantiate dquot if needed */ 402 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) { 403 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); 404 /* Write the info if needed */ 405 if (info_dirty(&dqopt->info[dquot->dq_type])) { 406 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 407 dquot->dq_sb, dquot->dq_type); 408 } 409 if (ret < 0) 410 goto out_iolock; 411 if (ret2 < 0) { 412 ret = ret2; 413 goto out_iolock; 414 } 415 } 416 set_bit(DQ_ACTIVE_B, &dquot->dq_flags); 417 out_iolock: 418 mutex_unlock(&dqopt->dqio_mutex); 419 mutex_unlock(&dquot->dq_lock); 420 return ret; 421 } 422 EXPORT_SYMBOL(dquot_acquire); 423 424 /* 425 * Write dquot to disk 426 */ 427 int dquot_commit(struct dquot *dquot) 428 { 429 int ret = 0, ret2 = 0; 430 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 431 432 mutex_lock(&dqopt->dqio_mutex); 433 spin_lock(&dq_list_lock); 434 if (!clear_dquot_dirty(dquot)) { 435 spin_unlock(&dq_list_lock); 436 goto out_sem; 437 } 438 spin_unlock(&dq_list_lock); 439 /* Inactive dquot can be only if there was error during read/init 440 * => we have better not writing it */ 441 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 442 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); 443 if (info_dirty(&dqopt->info[dquot->dq_type])) { 444 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 445 dquot->dq_sb, dquot->dq_type); 446 } 447 if (ret >= 0) 448 ret = ret2; 449 } 450 out_sem: 451 mutex_unlock(&dqopt->dqio_mutex); 452 return ret; 453 } 454 EXPORT_SYMBOL(dquot_commit); 455 456 /* 457 * Release dquot 458 */ 459 int dquot_release(struct dquot *dquot) 460 { 461 int ret = 0, ret2 = 0; 462 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 463 464 mutex_lock(&dquot->dq_lock); 465 /* Check whether we are not racing with some other dqget() */ 466 if (atomic_read(&dquot->dq_count) > 1) 467 goto out_dqlock; 468 mutex_lock(&dqopt->dqio_mutex); 469 if (dqopt->ops[dquot->dq_type]->release_dqblk) { 470 ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot); 471 /* Write the info */ 472 if (info_dirty(&dqopt->info[dquot->dq_type])) { 473 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 474 dquot->dq_sb, dquot->dq_type); 475 } 476 if (ret >= 0) 477 ret = ret2; 478 } 479 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags); 480 mutex_unlock(&dqopt->dqio_mutex); 481 out_dqlock: 482 mutex_unlock(&dquot->dq_lock); 483 return ret; 484 } 485 EXPORT_SYMBOL(dquot_release); 486 487 void dquot_destroy(struct dquot *dquot) 488 { 489 kmem_cache_free(dquot_cachep, dquot); 490 } 491 EXPORT_SYMBOL(dquot_destroy); 492 493 static inline void do_destroy_dquot(struct dquot *dquot) 494 { 495 dquot->dq_sb->dq_op->destroy_dquot(dquot); 496 } 497 498 /* Invalidate all dquots on the list. Note that this function is called after 499 * quota is disabled and pointers from inodes removed so there cannot be new 500 * quota users. There can still be some users of quotas due to inodes being 501 * just deleted or pruned by prune_icache() (those are not attached to any 502 * list) or parallel quotactl call. We have to wait for such users. 503 */ 504 static void invalidate_dquots(struct super_block *sb, int type) 505 { 506 struct dquot *dquot, *tmp; 507 508 restart: 509 spin_lock(&dq_list_lock); 510 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) { 511 if (dquot->dq_sb != sb) 512 continue; 513 if (dquot->dq_type != type) 514 continue; 515 /* Wait for dquot users */ 516 if (atomic_read(&dquot->dq_count)) { 517 DEFINE_WAIT(wait); 518 519 atomic_inc(&dquot->dq_count); 520 prepare_to_wait(&dquot->dq_wait_unused, &wait, 521 TASK_UNINTERRUPTIBLE); 522 spin_unlock(&dq_list_lock); 523 /* Once dqput() wakes us up, we know it's time to free 524 * the dquot. 525 * IMPORTANT: we rely on the fact that there is always 526 * at most one process waiting for dquot to free. 527 * Otherwise dq_count would be > 1 and we would never 528 * wake up. 529 */ 530 if (atomic_read(&dquot->dq_count) > 1) 531 schedule(); 532 finish_wait(&dquot->dq_wait_unused, &wait); 533 dqput(dquot); 534 /* At this moment dquot() need not exist (it could be 535 * reclaimed by prune_dqcache(). Hence we must 536 * restart. */ 537 goto restart; 538 } 539 /* 540 * Quota now has no users and it has been written on last 541 * dqput() 542 */ 543 remove_dquot_hash(dquot); 544 remove_free_dquot(dquot); 545 remove_inuse(dquot); 546 do_destroy_dquot(dquot); 547 } 548 spin_unlock(&dq_list_lock); 549 } 550 551 /* Call callback for every active dquot on given filesystem */ 552 int dquot_scan_active(struct super_block *sb, 553 int (*fn)(struct dquot *dquot, unsigned long priv), 554 unsigned long priv) 555 { 556 struct dquot *dquot, *old_dquot = NULL; 557 int ret = 0; 558 559 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 560 spin_lock(&dq_list_lock); 561 list_for_each_entry(dquot, &inuse_list, dq_inuse) { 562 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) 563 continue; 564 if (dquot->dq_sb != sb) 565 continue; 566 /* Now we have active dquot so we can just increase use count */ 567 atomic_inc(&dquot->dq_count); 568 spin_unlock(&dq_list_lock); 569 dqstats_inc(DQST_LOOKUPS); 570 dqput(old_dquot); 571 old_dquot = dquot; 572 ret = fn(dquot, priv); 573 if (ret < 0) 574 goto out; 575 spin_lock(&dq_list_lock); 576 /* We are safe to continue now because our dquot could not 577 * be moved out of the inuse list while we hold the reference */ 578 } 579 spin_unlock(&dq_list_lock); 580 out: 581 dqput(old_dquot); 582 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 583 return ret; 584 } 585 EXPORT_SYMBOL(dquot_scan_active); 586 587 int vfs_quota_sync(struct super_block *sb, int type, int wait) 588 { 589 struct list_head *dirty; 590 struct dquot *dquot; 591 struct quota_info *dqopt = sb_dqopt(sb); 592 int cnt; 593 594 mutex_lock(&dqopt->dqonoff_mutex); 595 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 596 if (type != -1 && cnt != type) 597 continue; 598 if (!sb_has_quota_active(sb, cnt)) 599 continue; 600 spin_lock(&dq_list_lock); 601 dirty = &dqopt->info[cnt].dqi_dirty_list; 602 while (!list_empty(dirty)) { 603 dquot = list_first_entry(dirty, struct dquot, 604 dq_dirty); 605 /* Dirty and inactive can be only bad dquot... */ 606 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 607 clear_dquot_dirty(dquot); 608 continue; 609 } 610 /* Now we have active dquot from which someone is 611 * holding reference so we can safely just increase 612 * use count */ 613 atomic_inc(&dquot->dq_count); 614 spin_unlock(&dq_list_lock); 615 dqstats_inc(DQST_LOOKUPS); 616 sb->dq_op->write_dquot(dquot); 617 dqput(dquot); 618 spin_lock(&dq_list_lock); 619 } 620 spin_unlock(&dq_list_lock); 621 } 622 623 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 624 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt) 625 && info_dirty(&dqopt->info[cnt])) 626 sb->dq_op->write_info(sb, cnt); 627 dqstats_inc(DQST_SYNCS); 628 mutex_unlock(&dqopt->dqonoff_mutex); 629 630 if (!wait || (sb_dqopt(sb)->flags & DQUOT_QUOTA_SYS_FILE)) 631 return 0; 632 633 /* This is not very clever (and fast) but currently I don't know about 634 * any other simple way of getting quota data to disk and we must get 635 * them there for userspace to be visible... */ 636 if (sb->s_op->sync_fs) 637 sb->s_op->sync_fs(sb, 1); 638 sync_blockdev(sb->s_bdev); 639 640 /* 641 * Now when everything is written we can discard the pagecache so 642 * that userspace sees the changes. 643 */ 644 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 645 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 646 if (type != -1 && cnt != type) 647 continue; 648 if (!sb_has_quota_active(sb, cnt)) 649 continue; 650 mutex_lock_nested(&sb_dqopt(sb)->files[cnt]->i_mutex, 651 I_MUTEX_QUOTA); 652 truncate_inode_pages(&sb_dqopt(sb)->files[cnt]->i_data, 0); 653 mutex_unlock(&sb_dqopt(sb)->files[cnt]->i_mutex); 654 } 655 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 656 657 return 0; 658 } 659 EXPORT_SYMBOL(vfs_quota_sync); 660 661 /* Free unused dquots from cache */ 662 static void prune_dqcache(int count) 663 { 664 struct list_head *head; 665 struct dquot *dquot; 666 667 head = free_dquots.prev; 668 while (head != &free_dquots && count) { 669 dquot = list_entry(head, struct dquot, dq_free); 670 remove_dquot_hash(dquot); 671 remove_free_dquot(dquot); 672 remove_inuse(dquot); 673 do_destroy_dquot(dquot); 674 count--; 675 head = free_dquots.prev; 676 } 677 } 678 679 static int dqstats_read(unsigned int type) 680 { 681 int count = 0; 682 #ifdef CONFIG_SMP 683 int cpu; 684 for_each_possible_cpu(cpu) 685 count += per_cpu_ptr(dqstats_pcpu, cpu)->stat[type]; 686 /* Statistics reading is racy, but absolute accuracy isn't required */ 687 if (count < 0) 688 count = 0; 689 #else 690 count = dqstats.stat[type]; 691 #endif 692 return count; 693 } 694 695 /* 696 * This is called from kswapd when we think we need some 697 * more memory 698 */ 699 700 static int shrink_dqcache_memory(int nr, gfp_t gfp_mask) 701 { 702 if (nr) { 703 spin_lock(&dq_list_lock); 704 prune_dqcache(nr); 705 spin_unlock(&dq_list_lock); 706 } 707 return (dqstats_read(DQST_FREE_DQUOTS)/100) * sysctl_vfs_cache_pressure; 708 } 709 710 static struct shrinker dqcache_shrinker = { 711 .shrink = shrink_dqcache_memory, 712 .seeks = DEFAULT_SEEKS, 713 }; 714 715 /* 716 * Put reference to dquot 717 * NOTE: If you change this function please check whether dqput_blocks() works right... 718 */ 719 void dqput(struct dquot *dquot) 720 { 721 int ret; 722 723 if (!dquot) 724 return; 725 #ifdef CONFIG_QUOTA_DEBUG 726 if (!atomic_read(&dquot->dq_count)) { 727 printk("VFS: dqput: trying to free free dquot\n"); 728 printk("VFS: device %s, dquot of %s %d\n", 729 dquot->dq_sb->s_id, 730 quotatypes[dquot->dq_type], 731 dquot->dq_id); 732 BUG(); 733 } 734 #endif 735 dqstats_inc(DQST_DROPS); 736 we_slept: 737 spin_lock(&dq_list_lock); 738 if (atomic_read(&dquot->dq_count) > 1) { 739 /* We have more than one user... nothing to do */ 740 atomic_dec(&dquot->dq_count); 741 /* Releasing dquot during quotaoff phase? */ 742 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) && 743 atomic_read(&dquot->dq_count) == 1) 744 wake_up(&dquot->dq_wait_unused); 745 spin_unlock(&dq_list_lock); 746 return; 747 } 748 /* Need to release dquot? */ 749 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { 750 spin_unlock(&dq_list_lock); 751 /* Commit dquot before releasing */ 752 ret = dquot->dq_sb->dq_op->write_dquot(dquot); 753 if (ret < 0) { 754 printk(KERN_ERR "VFS: cannot write quota structure on " 755 "device %s (error %d). Quota may get out of " 756 "sync!\n", dquot->dq_sb->s_id, ret); 757 /* 758 * We clear dirty bit anyway, so that we avoid 759 * infinite loop here 760 */ 761 spin_lock(&dq_list_lock); 762 clear_dquot_dirty(dquot); 763 spin_unlock(&dq_list_lock); 764 } 765 goto we_slept; 766 } 767 /* Clear flag in case dquot was inactive (something bad happened) */ 768 clear_dquot_dirty(dquot); 769 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 770 spin_unlock(&dq_list_lock); 771 dquot->dq_sb->dq_op->release_dquot(dquot); 772 goto we_slept; 773 } 774 atomic_dec(&dquot->dq_count); 775 #ifdef CONFIG_QUOTA_DEBUG 776 /* sanity check */ 777 BUG_ON(!list_empty(&dquot->dq_free)); 778 #endif 779 put_dquot_last(dquot); 780 spin_unlock(&dq_list_lock); 781 } 782 EXPORT_SYMBOL(dqput); 783 784 struct dquot *dquot_alloc(struct super_block *sb, int type) 785 { 786 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); 787 } 788 EXPORT_SYMBOL(dquot_alloc); 789 790 static struct dquot *get_empty_dquot(struct super_block *sb, int type) 791 { 792 struct dquot *dquot; 793 794 dquot = sb->dq_op->alloc_dquot(sb, type); 795 if(!dquot) 796 return NULL; 797 798 mutex_init(&dquot->dq_lock); 799 INIT_LIST_HEAD(&dquot->dq_free); 800 INIT_LIST_HEAD(&dquot->dq_inuse); 801 INIT_HLIST_NODE(&dquot->dq_hash); 802 INIT_LIST_HEAD(&dquot->dq_dirty); 803 init_waitqueue_head(&dquot->dq_wait_unused); 804 dquot->dq_sb = sb; 805 dquot->dq_type = type; 806 atomic_set(&dquot->dq_count, 1); 807 808 return dquot; 809 } 810 811 /* 812 * Get reference to dquot 813 * 814 * Locking is slightly tricky here. We are guarded from parallel quotaoff() 815 * destroying our dquot by: 816 * a) checking for quota flags under dq_list_lock and 817 * b) getting a reference to dquot before we release dq_list_lock 818 */ 819 struct dquot *dqget(struct super_block *sb, unsigned int id, int type) 820 { 821 unsigned int hashent = hashfn(sb, id, type); 822 struct dquot *dquot = NULL, *empty = NULL; 823 824 if (!sb_has_quota_active(sb, type)) 825 return NULL; 826 we_slept: 827 spin_lock(&dq_list_lock); 828 spin_lock(&dq_state_lock); 829 if (!sb_has_quota_active(sb, type)) { 830 spin_unlock(&dq_state_lock); 831 spin_unlock(&dq_list_lock); 832 goto out; 833 } 834 spin_unlock(&dq_state_lock); 835 836 dquot = find_dquot(hashent, sb, id, type); 837 if (!dquot) { 838 if (!empty) { 839 spin_unlock(&dq_list_lock); 840 empty = get_empty_dquot(sb, type); 841 if (!empty) 842 schedule(); /* Try to wait for a moment... */ 843 goto we_slept; 844 } 845 dquot = empty; 846 empty = NULL; 847 dquot->dq_id = id; 848 /* all dquots go on the inuse_list */ 849 put_inuse(dquot); 850 /* hash it first so it can be found */ 851 insert_dquot_hash(dquot); 852 spin_unlock(&dq_list_lock); 853 dqstats_inc(DQST_LOOKUPS); 854 } else { 855 if (!atomic_read(&dquot->dq_count)) 856 remove_free_dquot(dquot); 857 atomic_inc(&dquot->dq_count); 858 spin_unlock(&dq_list_lock); 859 dqstats_inc(DQST_CACHE_HITS); 860 dqstats_inc(DQST_LOOKUPS); 861 } 862 /* Wait for dq_lock - after this we know that either dquot_release() is 863 * already finished or it will be canceled due to dq_count > 1 test */ 864 wait_on_dquot(dquot); 865 /* Read the dquot / allocate space in quota file */ 866 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && 867 sb->dq_op->acquire_dquot(dquot) < 0) { 868 dqput(dquot); 869 dquot = NULL; 870 goto out; 871 } 872 #ifdef CONFIG_QUOTA_DEBUG 873 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ 874 #endif 875 out: 876 if (empty) 877 do_destroy_dquot(empty); 878 879 return dquot; 880 } 881 EXPORT_SYMBOL(dqget); 882 883 static int dqinit_needed(struct inode *inode, int type) 884 { 885 int cnt; 886 887 if (IS_NOQUOTA(inode)) 888 return 0; 889 if (type != -1) 890 return !inode->i_dquot[type]; 891 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 892 if (!inode->i_dquot[cnt]) 893 return 1; 894 return 0; 895 } 896 897 /* This routine is guarded by dqonoff_mutex mutex */ 898 static void add_dquot_ref(struct super_block *sb, int type) 899 { 900 struct inode *inode, *old_inode = NULL; 901 #ifdef CONFIG_QUOTA_DEBUG 902 int reserved = 0; 903 #endif 904 905 spin_lock(&inode_lock); 906 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 907 if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE|I_NEW)) 908 continue; 909 #ifdef CONFIG_QUOTA_DEBUG 910 if (unlikely(inode_get_rsv_space(inode) > 0)) 911 reserved = 1; 912 #endif 913 if (!atomic_read(&inode->i_writecount)) 914 continue; 915 if (!dqinit_needed(inode, type)) 916 continue; 917 918 __iget(inode); 919 spin_unlock(&inode_lock); 920 921 iput(old_inode); 922 __dquot_initialize(inode, type); 923 /* We hold a reference to 'inode' so it couldn't have been 924 * removed from s_inodes list while we dropped the inode_lock. 925 * We cannot iput the inode now as we can be holding the last 926 * reference and we cannot iput it under inode_lock. So we 927 * keep the reference and iput it later. */ 928 old_inode = inode; 929 spin_lock(&inode_lock); 930 } 931 spin_unlock(&inode_lock); 932 iput(old_inode); 933 934 #ifdef CONFIG_QUOTA_DEBUG 935 if (reserved) { 936 printk(KERN_WARNING "VFS (%s): Writes happened before quota" 937 " was turned on thus quota information is probably " 938 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 939 } 940 #endif 941 } 942 943 /* 944 * Return 0 if dqput() won't block. 945 * (note that 1 doesn't necessarily mean blocking) 946 */ 947 static inline int dqput_blocks(struct dquot *dquot) 948 { 949 if (atomic_read(&dquot->dq_count) <= 1) 950 return 1; 951 return 0; 952 } 953 954 /* 955 * Remove references to dquots from inode and add dquot to list for freeing 956 * if we have the last referece to dquot 957 * We can't race with anybody because we hold dqptr_sem for writing... 958 */ 959 static int remove_inode_dquot_ref(struct inode *inode, int type, 960 struct list_head *tofree_head) 961 { 962 struct dquot *dquot = inode->i_dquot[type]; 963 964 inode->i_dquot[type] = NULL; 965 if (dquot) { 966 if (dqput_blocks(dquot)) { 967 #ifdef CONFIG_QUOTA_DEBUG 968 if (atomic_read(&dquot->dq_count) != 1) 969 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count)); 970 #endif 971 spin_lock(&dq_list_lock); 972 /* As dquot must have currently users it can't be on 973 * the free list... */ 974 list_add(&dquot->dq_free, tofree_head); 975 spin_unlock(&dq_list_lock); 976 return 1; 977 } 978 else 979 dqput(dquot); /* We have guaranteed we won't block */ 980 } 981 return 0; 982 } 983 984 /* 985 * Free list of dquots 986 * Dquots are removed from inodes and no new references can be got so we are 987 * the only ones holding reference 988 */ 989 static void put_dquot_list(struct list_head *tofree_head) 990 { 991 struct list_head *act_head; 992 struct dquot *dquot; 993 994 act_head = tofree_head->next; 995 while (act_head != tofree_head) { 996 dquot = list_entry(act_head, struct dquot, dq_free); 997 act_head = act_head->next; 998 /* Remove dquot from the list so we won't have problems... */ 999 list_del_init(&dquot->dq_free); 1000 dqput(dquot); 1001 } 1002 } 1003 1004 static void remove_dquot_ref(struct super_block *sb, int type, 1005 struct list_head *tofree_head) 1006 { 1007 struct inode *inode; 1008 1009 spin_lock(&inode_lock); 1010 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 1011 /* 1012 * We have to scan also I_NEW inodes because they can already 1013 * have quota pointer initialized. Luckily, we need to touch 1014 * only quota pointers and these have separate locking 1015 * (dqptr_sem). 1016 */ 1017 if (!IS_NOQUOTA(inode)) 1018 remove_inode_dquot_ref(inode, type, tofree_head); 1019 } 1020 spin_unlock(&inode_lock); 1021 } 1022 1023 /* Gather all references from inodes and drop them */ 1024 static void drop_dquot_ref(struct super_block *sb, int type) 1025 { 1026 LIST_HEAD(tofree_head); 1027 1028 if (sb->dq_op) { 1029 down_write(&sb_dqopt(sb)->dqptr_sem); 1030 remove_dquot_ref(sb, type, &tofree_head); 1031 up_write(&sb_dqopt(sb)->dqptr_sem); 1032 put_dquot_list(&tofree_head); 1033 } 1034 } 1035 1036 static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1037 { 1038 dquot->dq_dqb.dqb_curinodes += number; 1039 } 1040 1041 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1042 { 1043 dquot->dq_dqb.dqb_curspace += number; 1044 } 1045 1046 static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1047 { 1048 dquot->dq_dqb.dqb_rsvspace += number; 1049 } 1050 1051 /* 1052 * Claim reserved quota space 1053 */ 1054 static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1055 { 1056 if (dquot->dq_dqb.dqb_rsvspace < number) { 1057 WARN_ON_ONCE(1); 1058 number = dquot->dq_dqb.dqb_rsvspace; 1059 } 1060 dquot->dq_dqb.dqb_curspace += number; 1061 dquot->dq_dqb.dqb_rsvspace -= number; 1062 } 1063 1064 static inline 1065 void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1066 { 1067 if (dquot->dq_dqb.dqb_rsvspace >= number) 1068 dquot->dq_dqb.dqb_rsvspace -= number; 1069 else { 1070 WARN_ON_ONCE(1); 1071 dquot->dq_dqb.dqb_rsvspace = 0; 1072 } 1073 } 1074 1075 static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1076 { 1077 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1078 dquot->dq_dqb.dqb_curinodes >= number) 1079 dquot->dq_dqb.dqb_curinodes -= number; 1080 else 1081 dquot->dq_dqb.dqb_curinodes = 0; 1082 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1083 dquot->dq_dqb.dqb_itime = (time_t) 0; 1084 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1085 } 1086 1087 static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1088 { 1089 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1090 dquot->dq_dqb.dqb_curspace >= number) 1091 dquot->dq_dqb.dqb_curspace -= number; 1092 else 1093 dquot->dq_dqb.dqb_curspace = 0; 1094 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1095 dquot->dq_dqb.dqb_btime = (time_t) 0; 1096 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1097 } 1098 1099 static int warning_issued(struct dquot *dquot, const int warntype) 1100 { 1101 int flag = (warntype == QUOTA_NL_BHARDWARN || 1102 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1103 ((warntype == QUOTA_NL_IHARDWARN || 1104 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1105 1106 if (!flag) 1107 return 0; 1108 return test_and_set_bit(flag, &dquot->dq_flags); 1109 } 1110 1111 #ifdef CONFIG_PRINT_QUOTA_WARNING 1112 static int flag_print_warnings = 1; 1113 1114 static int need_print_warning(struct dquot *dquot) 1115 { 1116 if (!flag_print_warnings) 1117 return 0; 1118 1119 switch (dquot->dq_type) { 1120 case USRQUOTA: 1121 return current_fsuid() == dquot->dq_id; 1122 case GRPQUOTA: 1123 return in_group_p(dquot->dq_id); 1124 } 1125 return 0; 1126 } 1127 1128 /* Print warning to user which exceeded quota */ 1129 static void print_warning(struct dquot *dquot, const int warntype) 1130 { 1131 char *msg = NULL; 1132 struct tty_struct *tty; 1133 1134 if (warntype == QUOTA_NL_IHARDBELOW || 1135 warntype == QUOTA_NL_ISOFTBELOW || 1136 warntype == QUOTA_NL_BHARDBELOW || 1137 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot)) 1138 return; 1139 1140 tty = get_current_tty(); 1141 if (!tty) 1142 return; 1143 tty_write_message(tty, dquot->dq_sb->s_id); 1144 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1145 tty_write_message(tty, ": warning, "); 1146 else 1147 tty_write_message(tty, ": write failed, "); 1148 tty_write_message(tty, quotatypes[dquot->dq_type]); 1149 switch (warntype) { 1150 case QUOTA_NL_IHARDWARN: 1151 msg = " file limit reached.\r\n"; 1152 break; 1153 case QUOTA_NL_ISOFTLONGWARN: 1154 msg = " file quota exceeded too long.\r\n"; 1155 break; 1156 case QUOTA_NL_ISOFTWARN: 1157 msg = " file quota exceeded.\r\n"; 1158 break; 1159 case QUOTA_NL_BHARDWARN: 1160 msg = " block limit reached.\r\n"; 1161 break; 1162 case QUOTA_NL_BSOFTLONGWARN: 1163 msg = " block quota exceeded too long.\r\n"; 1164 break; 1165 case QUOTA_NL_BSOFTWARN: 1166 msg = " block quota exceeded.\r\n"; 1167 break; 1168 } 1169 tty_write_message(tty, msg); 1170 tty_kref_put(tty); 1171 } 1172 #endif 1173 1174 /* 1175 * Write warnings to the console and send warning messages over netlink. 1176 * 1177 * Note that this function can sleep. 1178 */ 1179 static void flush_warnings(struct dquot *const *dquots, char *warntype) 1180 { 1181 struct dquot *dq; 1182 int i; 1183 1184 for (i = 0; i < MAXQUOTAS; i++) { 1185 dq = dquots[i]; 1186 if (dq && warntype[i] != QUOTA_NL_NOWARN && 1187 !warning_issued(dq, warntype[i])) { 1188 #ifdef CONFIG_PRINT_QUOTA_WARNING 1189 print_warning(dq, warntype[i]); 1190 #endif 1191 quota_send_warning(dq->dq_type, dq->dq_id, 1192 dq->dq_sb->s_dev, warntype[i]); 1193 } 1194 } 1195 } 1196 1197 static int ignore_hardlimit(struct dquot *dquot) 1198 { 1199 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 1200 1201 return capable(CAP_SYS_RESOURCE) && 1202 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1203 !(info->dqi_flags & V1_DQF_RSQUASH)); 1204 } 1205 1206 /* needs dq_data_lock */ 1207 static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) 1208 { 1209 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1210 1211 *warntype = QUOTA_NL_NOWARN; 1212 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || 1213 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1214 return 0; 1215 1216 if (dquot->dq_dqb.dqb_ihardlimit && 1217 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1218 !ignore_hardlimit(dquot)) { 1219 *warntype = QUOTA_NL_IHARDWARN; 1220 return -EDQUOT; 1221 } 1222 1223 if (dquot->dq_dqb.dqb_isoftlimit && 1224 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1225 dquot->dq_dqb.dqb_itime && 1226 get_seconds() >= dquot->dq_dqb.dqb_itime && 1227 !ignore_hardlimit(dquot)) { 1228 *warntype = QUOTA_NL_ISOFTLONGWARN; 1229 return -EDQUOT; 1230 } 1231 1232 if (dquot->dq_dqb.dqb_isoftlimit && 1233 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1234 dquot->dq_dqb.dqb_itime == 0) { 1235 *warntype = QUOTA_NL_ISOFTWARN; 1236 dquot->dq_dqb.dqb_itime = get_seconds() + 1237 sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; 1238 } 1239 1240 return 0; 1241 } 1242 1243 /* needs dq_data_lock */ 1244 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) 1245 { 1246 qsize_t tspace; 1247 struct super_block *sb = dquot->dq_sb; 1248 1249 *warntype = QUOTA_NL_NOWARN; 1250 if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) || 1251 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1252 return 0; 1253 1254 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1255 + space; 1256 1257 if (dquot->dq_dqb.dqb_bhardlimit && 1258 tspace > dquot->dq_dqb.dqb_bhardlimit && 1259 !ignore_hardlimit(dquot)) { 1260 if (!prealloc) 1261 *warntype = QUOTA_NL_BHARDWARN; 1262 return -EDQUOT; 1263 } 1264 1265 if (dquot->dq_dqb.dqb_bsoftlimit && 1266 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1267 dquot->dq_dqb.dqb_btime && 1268 get_seconds() >= dquot->dq_dqb.dqb_btime && 1269 !ignore_hardlimit(dquot)) { 1270 if (!prealloc) 1271 *warntype = QUOTA_NL_BSOFTLONGWARN; 1272 return -EDQUOT; 1273 } 1274 1275 if (dquot->dq_dqb.dqb_bsoftlimit && 1276 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1277 dquot->dq_dqb.dqb_btime == 0) { 1278 if (!prealloc) { 1279 *warntype = QUOTA_NL_BSOFTWARN; 1280 dquot->dq_dqb.dqb_btime = get_seconds() + 1281 sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace; 1282 } 1283 else 1284 /* 1285 * We don't allow preallocation to exceed softlimit so exceeding will 1286 * be always printed 1287 */ 1288 return -EDQUOT; 1289 } 1290 1291 return 0; 1292 } 1293 1294 static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1295 { 1296 qsize_t newinodes; 1297 1298 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1299 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1300 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type)) 1301 return QUOTA_NL_NOWARN; 1302 1303 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1304 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1305 return QUOTA_NL_ISOFTBELOW; 1306 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1307 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1308 return QUOTA_NL_IHARDBELOW; 1309 return QUOTA_NL_NOWARN; 1310 } 1311 1312 static int info_bdq_free(struct dquot *dquot, qsize_t space) 1313 { 1314 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1315 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1316 return QUOTA_NL_NOWARN; 1317 1318 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1319 return QUOTA_NL_BSOFTBELOW; 1320 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1321 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1322 return QUOTA_NL_BHARDBELOW; 1323 return QUOTA_NL_NOWARN; 1324 } 1325 1326 /* 1327 * Initialize quota pointers in inode 1328 * 1329 * We do things in a bit complicated way but by that we avoid calling 1330 * dqget() and thus filesystem callbacks under dqptr_sem. 1331 * 1332 * It is better to call this function outside of any transaction as it 1333 * might need a lot of space in journal for dquot structure allocation. 1334 */ 1335 static void __dquot_initialize(struct inode *inode, int type) 1336 { 1337 unsigned int id = 0; 1338 int cnt; 1339 struct dquot *got[MAXQUOTAS]; 1340 struct super_block *sb = inode->i_sb; 1341 qsize_t rsv; 1342 1343 /* First test before acquiring mutex - solves deadlocks when we 1344 * re-enter the quota code and are already holding the mutex */ 1345 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1346 return; 1347 1348 /* First get references to structures we might need. */ 1349 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1350 got[cnt] = NULL; 1351 if (type != -1 && cnt != type) 1352 continue; 1353 switch (cnt) { 1354 case USRQUOTA: 1355 id = inode->i_uid; 1356 break; 1357 case GRPQUOTA: 1358 id = inode->i_gid; 1359 break; 1360 } 1361 got[cnt] = dqget(sb, id, cnt); 1362 } 1363 1364 down_write(&sb_dqopt(sb)->dqptr_sem); 1365 if (IS_NOQUOTA(inode)) 1366 goto out_err; 1367 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1368 if (type != -1 && cnt != type) 1369 continue; 1370 /* Avoid races with quotaoff() */ 1371 if (!sb_has_quota_active(sb, cnt)) 1372 continue; 1373 if (!inode->i_dquot[cnt]) { 1374 inode->i_dquot[cnt] = got[cnt]; 1375 got[cnt] = NULL; 1376 /* 1377 * Make quota reservation system happy if someone 1378 * did a write before quota was turned on 1379 */ 1380 rsv = inode_get_rsv_space(inode); 1381 if (unlikely(rsv)) 1382 dquot_resv_space(inode->i_dquot[cnt], rsv); 1383 } 1384 } 1385 out_err: 1386 up_write(&sb_dqopt(sb)->dqptr_sem); 1387 /* Drop unused references */ 1388 dqput_all(got); 1389 } 1390 1391 void dquot_initialize(struct inode *inode) 1392 { 1393 __dquot_initialize(inode, -1); 1394 } 1395 EXPORT_SYMBOL(dquot_initialize); 1396 1397 /* 1398 * Release all quotas referenced by inode 1399 */ 1400 static void __dquot_drop(struct inode *inode) 1401 { 1402 int cnt; 1403 struct dquot *put[MAXQUOTAS]; 1404 1405 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1406 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1407 put[cnt] = inode->i_dquot[cnt]; 1408 inode->i_dquot[cnt] = NULL; 1409 } 1410 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1411 dqput_all(put); 1412 } 1413 1414 void dquot_drop(struct inode *inode) 1415 { 1416 int cnt; 1417 1418 if (IS_NOQUOTA(inode)) 1419 return; 1420 1421 /* 1422 * Test before calling to rule out calls from proc and such 1423 * where we are not allowed to block. Note that this is 1424 * actually reliable test even without the lock - the caller 1425 * must assure that nobody can come after the DQUOT_DROP and 1426 * add quota pointers back anyway. 1427 */ 1428 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1429 if (inode->i_dquot[cnt]) 1430 break; 1431 } 1432 1433 if (cnt < MAXQUOTAS) 1434 __dquot_drop(inode); 1435 } 1436 EXPORT_SYMBOL(dquot_drop); 1437 1438 /* 1439 * inode_reserved_space is managed internally by quota, and protected by 1440 * i_lock similar to i_blocks+i_bytes. 1441 */ 1442 static qsize_t *inode_reserved_space(struct inode * inode) 1443 { 1444 /* Filesystem must explicitly define it's own method in order to use 1445 * quota reservation interface */ 1446 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1447 return inode->i_sb->dq_op->get_reserved_space(inode); 1448 } 1449 1450 void inode_add_rsv_space(struct inode *inode, qsize_t number) 1451 { 1452 spin_lock(&inode->i_lock); 1453 *inode_reserved_space(inode) += number; 1454 spin_unlock(&inode->i_lock); 1455 } 1456 EXPORT_SYMBOL(inode_add_rsv_space); 1457 1458 void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1459 { 1460 spin_lock(&inode->i_lock); 1461 *inode_reserved_space(inode) -= number; 1462 __inode_add_bytes(inode, number); 1463 spin_unlock(&inode->i_lock); 1464 } 1465 EXPORT_SYMBOL(inode_claim_rsv_space); 1466 1467 void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1468 { 1469 spin_lock(&inode->i_lock); 1470 *inode_reserved_space(inode) -= number; 1471 spin_unlock(&inode->i_lock); 1472 } 1473 EXPORT_SYMBOL(inode_sub_rsv_space); 1474 1475 static qsize_t inode_get_rsv_space(struct inode *inode) 1476 { 1477 qsize_t ret; 1478 1479 if (!inode->i_sb->dq_op->get_reserved_space) 1480 return 0; 1481 spin_lock(&inode->i_lock); 1482 ret = *inode_reserved_space(inode); 1483 spin_unlock(&inode->i_lock); 1484 return ret; 1485 } 1486 1487 static void inode_incr_space(struct inode *inode, qsize_t number, 1488 int reserve) 1489 { 1490 if (reserve) 1491 inode_add_rsv_space(inode, number); 1492 else 1493 inode_add_bytes(inode, number); 1494 } 1495 1496 static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1497 { 1498 if (reserve) 1499 inode_sub_rsv_space(inode, number); 1500 else 1501 inode_sub_bytes(inode, number); 1502 } 1503 1504 /* 1505 * This functions updates i_blocks+i_bytes fields and quota information 1506 * (together with appropriate checks). 1507 * 1508 * NOTE: We absolutely rely on the fact that caller dirties the inode 1509 * (usually helpers in quotaops.h care about this) and holds a handle for 1510 * the current transaction so that dquot write and inode write go into the 1511 * same transaction. 1512 */ 1513 1514 /* 1515 * This operation can block, but only after everything is updated 1516 */ 1517 int __dquot_alloc_space(struct inode *inode, qsize_t number, 1518 int warn, int reserve) 1519 { 1520 int cnt, ret = 0; 1521 char warntype[MAXQUOTAS]; 1522 1523 /* 1524 * First test before acquiring mutex - solves deadlocks when we 1525 * re-enter the quota code and are already holding the mutex 1526 */ 1527 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1528 inode_incr_space(inode, number, reserve); 1529 goto out; 1530 } 1531 1532 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1533 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1534 warntype[cnt] = QUOTA_NL_NOWARN; 1535 1536 spin_lock(&dq_data_lock); 1537 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1538 if (!inode->i_dquot[cnt]) 1539 continue; 1540 ret = check_bdq(inode->i_dquot[cnt], number, !warn, 1541 warntype+cnt); 1542 if (ret) { 1543 spin_unlock(&dq_data_lock); 1544 goto out_flush_warn; 1545 } 1546 } 1547 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1548 if (!inode->i_dquot[cnt]) 1549 continue; 1550 if (reserve) 1551 dquot_resv_space(inode->i_dquot[cnt], number); 1552 else 1553 dquot_incr_space(inode->i_dquot[cnt], number); 1554 } 1555 inode_incr_space(inode, number, reserve); 1556 spin_unlock(&dq_data_lock); 1557 1558 if (reserve) 1559 goto out_flush_warn; 1560 mark_all_dquot_dirty(inode->i_dquot); 1561 out_flush_warn: 1562 flush_warnings(inode->i_dquot, warntype); 1563 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1564 out: 1565 return ret; 1566 } 1567 EXPORT_SYMBOL(__dquot_alloc_space); 1568 1569 /* 1570 * This operation can block, but only after everything is updated 1571 */ 1572 int dquot_alloc_inode(const struct inode *inode) 1573 { 1574 int cnt, ret = 0; 1575 char warntype[MAXQUOTAS]; 1576 1577 /* First test before acquiring mutex - solves deadlocks when we 1578 * re-enter the quota code and are already holding the mutex */ 1579 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1580 return 0; 1581 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1582 warntype[cnt] = QUOTA_NL_NOWARN; 1583 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1584 spin_lock(&dq_data_lock); 1585 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1586 if (!inode->i_dquot[cnt]) 1587 continue; 1588 ret = check_idq(inode->i_dquot[cnt], 1, warntype + cnt); 1589 if (ret) 1590 goto warn_put_all; 1591 } 1592 1593 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1594 if (!inode->i_dquot[cnt]) 1595 continue; 1596 dquot_incr_inodes(inode->i_dquot[cnt], 1); 1597 } 1598 1599 warn_put_all: 1600 spin_unlock(&dq_data_lock); 1601 if (ret == 0) 1602 mark_all_dquot_dirty(inode->i_dquot); 1603 flush_warnings(inode->i_dquot, warntype); 1604 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1605 return ret; 1606 } 1607 EXPORT_SYMBOL(dquot_alloc_inode); 1608 1609 /* 1610 * Convert in-memory reserved quotas to real consumed quotas 1611 */ 1612 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1613 { 1614 int cnt; 1615 1616 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1617 inode_claim_rsv_space(inode, number); 1618 return 0; 1619 } 1620 1621 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1622 spin_lock(&dq_data_lock); 1623 /* Claim reserved quotas to allocated quotas */ 1624 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1625 if (inode->i_dquot[cnt]) 1626 dquot_claim_reserved_space(inode->i_dquot[cnt], 1627 number); 1628 } 1629 /* Update inode bytes */ 1630 inode_claim_rsv_space(inode, number); 1631 spin_unlock(&dq_data_lock); 1632 mark_all_dquot_dirty(inode->i_dquot); 1633 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1634 return 0; 1635 } 1636 EXPORT_SYMBOL(dquot_claim_space_nodirty); 1637 1638 /* 1639 * This operation can block, but only after everything is updated 1640 */ 1641 void __dquot_free_space(struct inode *inode, qsize_t number, int reserve) 1642 { 1643 unsigned int cnt; 1644 char warntype[MAXQUOTAS]; 1645 1646 /* First test before acquiring mutex - solves deadlocks when we 1647 * re-enter the quota code and are already holding the mutex */ 1648 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) { 1649 inode_decr_space(inode, number, reserve); 1650 return; 1651 } 1652 1653 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1654 spin_lock(&dq_data_lock); 1655 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1656 if (!inode->i_dquot[cnt]) 1657 continue; 1658 warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number); 1659 if (reserve) 1660 dquot_free_reserved_space(inode->i_dquot[cnt], number); 1661 else 1662 dquot_decr_space(inode->i_dquot[cnt], number); 1663 } 1664 inode_decr_space(inode, number, reserve); 1665 spin_unlock(&dq_data_lock); 1666 1667 if (reserve) 1668 goto out_unlock; 1669 mark_all_dquot_dirty(inode->i_dquot); 1670 out_unlock: 1671 flush_warnings(inode->i_dquot, warntype); 1672 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1673 } 1674 EXPORT_SYMBOL(__dquot_free_space); 1675 1676 /* 1677 * This operation can block, but only after everything is updated 1678 */ 1679 void dquot_free_inode(const struct inode *inode) 1680 { 1681 unsigned int cnt; 1682 char warntype[MAXQUOTAS]; 1683 1684 /* First test before acquiring mutex - solves deadlocks when we 1685 * re-enter the quota code and are already holding the mutex */ 1686 if (!sb_any_quota_active(inode->i_sb) || IS_NOQUOTA(inode)) 1687 return; 1688 1689 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1690 spin_lock(&dq_data_lock); 1691 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1692 if (!inode->i_dquot[cnt]) 1693 continue; 1694 warntype[cnt] = info_idq_free(inode->i_dquot[cnt], 1); 1695 dquot_decr_inodes(inode->i_dquot[cnt], 1); 1696 } 1697 spin_unlock(&dq_data_lock); 1698 mark_all_dquot_dirty(inode->i_dquot); 1699 flush_warnings(inode->i_dquot, warntype); 1700 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1701 } 1702 EXPORT_SYMBOL(dquot_free_inode); 1703 1704 /* 1705 * Transfer the number of inode and blocks from one diskquota to an other. 1706 * 1707 * This operation can block, but only after everything is updated 1708 * A transaction must be started when entering this function. 1709 */ 1710 static int __dquot_transfer(struct inode *inode, qid_t *chid, unsigned long mask) 1711 { 1712 qsize_t space, cur_space; 1713 qsize_t rsv_space = 0; 1714 struct dquot *transfer_from[MAXQUOTAS]; 1715 struct dquot *transfer_to[MAXQUOTAS]; 1716 int cnt, ret = 0; 1717 char warntype_to[MAXQUOTAS]; 1718 char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS]; 1719 1720 /* First test before acquiring mutex - solves deadlocks when we 1721 * re-enter the quota code and are already holding the mutex */ 1722 if (IS_NOQUOTA(inode)) 1723 return 0; 1724 /* Initialize the arrays */ 1725 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1726 transfer_from[cnt] = NULL; 1727 transfer_to[cnt] = NULL; 1728 warntype_to[cnt] = QUOTA_NL_NOWARN; 1729 } 1730 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1731 if (mask & (1 << cnt)) 1732 transfer_to[cnt] = dqget(inode->i_sb, chid[cnt], cnt); 1733 } 1734 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1735 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1736 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1737 goto put_all; 1738 } 1739 spin_lock(&dq_data_lock); 1740 cur_space = inode_get_bytes(inode); 1741 rsv_space = inode_get_rsv_space(inode); 1742 space = cur_space + rsv_space; 1743 /* Build the transfer_from list and check the limits */ 1744 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1745 if (!transfer_to[cnt]) 1746 continue; 1747 transfer_from[cnt] = inode->i_dquot[cnt]; 1748 ret = check_idq(transfer_to[cnt], 1, warntype_to + cnt); 1749 if (ret) 1750 goto over_quota; 1751 ret = check_bdq(transfer_to[cnt], space, 0, warntype_to + cnt); 1752 if (ret) 1753 goto over_quota; 1754 } 1755 1756 /* 1757 * Finally perform the needed transfer from transfer_from to transfer_to 1758 */ 1759 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1760 /* 1761 * Skip changes for same uid or gid or for turned off quota-type. 1762 */ 1763 if (!transfer_to[cnt]) 1764 continue; 1765 1766 /* Due to IO error we might not have transfer_from[] structure */ 1767 if (transfer_from[cnt]) { 1768 warntype_from_inodes[cnt] = 1769 info_idq_free(transfer_from[cnt], 1); 1770 warntype_from_space[cnt] = 1771 info_bdq_free(transfer_from[cnt], space); 1772 dquot_decr_inodes(transfer_from[cnt], 1); 1773 dquot_decr_space(transfer_from[cnt], cur_space); 1774 dquot_free_reserved_space(transfer_from[cnt], 1775 rsv_space); 1776 } 1777 1778 dquot_incr_inodes(transfer_to[cnt], 1); 1779 dquot_incr_space(transfer_to[cnt], cur_space); 1780 dquot_resv_space(transfer_to[cnt], rsv_space); 1781 1782 inode->i_dquot[cnt] = transfer_to[cnt]; 1783 } 1784 spin_unlock(&dq_data_lock); 1785 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1786 1787 mark_all_dquot_dirty(transfer_from); 1788 mark_all_dquot_dirty(transfer_to); 1789 /* The reference we got is transferred to the inode */ 1790 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1791 transfer_to[cnt] = NULL; 1792 warn_put_all: 1793 flush_warnings(transfer_to, warntype_to); 1794 flush_warnings(transfer_from, warntype_from_inodes); 1795 flush_warnings(transfer_from, warntype_from_space); 1796 put_all: 1797 dqput_all(transfer_from); 1798 dqput_all(transfer_to); 1799 return ret; 1800 over_quota: 1801 spin_unlock(&dq_data_lock); 1802 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1803 /* Clear dquot pointers we don't want to dqput() */ 1804 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1805 transfer_from[cnt] = NULL; 1806 goto warn_put_all; 1807 } 1808 1809 /* Wrapper for transferring ownership of an inode for uid/gid only 1810 * Called from FSXXX_setattr() 1811 */ 1812 int dquot_transfer(struct inode *inode, struct iattr *iattr) 1813 { 1814 qid_t chid[MAXQUOTAS]; 1815 unsigned long mask = 0; 1816 1817 if (iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) { 1818 mask |= 1 << USRQUOTA; 1819 chid[USRQUOTA] = iattr->ia_uid; 1820 } 1821 if (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid) { 1822 mask |= 1 << GRPQUOTA; 1823 chid[GRPQUOTA] = iattr->ia_gid; 1824 } 1825 if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) { 1826 dquot_initialize(inode); 1827 return __dquot_transfer(inode, chid, mask); 1828 } 1829 return 0; 1830 } 1831 EXPORT_SYMBOL(dquot_transfer); 1832 1833 /* 1834 * Write info of quota file to disk 1835 */ 1836 int dquot_commit_info(struct super_block *sb, int type) 1837 { 1838 int ret; 1839 struct quota_info *dqopt = sb_dqopt(sb); 1840 1841 mutex_lock(&dqopt->dqio_mutex); 1842 ret = dqopt->ops[type]->write_file_info(sb, type); 1843 mutex_unlock(&dqopt->dqio_mutex); 1844 return ret; 1845 } 1846 EXPORT_SYMBOL(dquot_commit_info); 1847 1848 /* 1849 * Definitions of diskquota operations. 1850 */ 1851 const struct dquot_operations dquot_operations = { 1852 .write_dquot = dquot_commit, 1853 .acquire_dquot = dquot_acquire, 1854 .release_dquot = dquot_release, 1855 .mark_dirty = dquot_mark_dquot_dirty, 1856 .write_info = dquot_commit_info, 1857 .alloc_dquot = dquot_alloc, 1858 .destroy_dquot = dquot_destroy, 1859 }; 1860 1861 /* 1862 * Generic helper for ->open on filesystems supporting disk quotas. 1863 */ 1864 int dquot_file_open(struct inode *inode, struct file *file) 1865 { 1866 int error; 1867 1868 error = generic_file_open(inode, file); 1869 if (!error && (file->f_mode & FMODE_WRITE)) 1870 dquot_initialize(inode); 1871 return error; 1872 } 1873 EXPORT_SYMBOL(dquot_file_open); 1874 1875 /* 1876 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 1877 */ 1878 int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags) 1879 { 1880 int cnt, ret = 0; 1881 struct quota_info *dqopt = sb_dqopt(sb); 1882 struct inode *toputinode[MAXQUOTAS]; 1883 1884 /* Cannot turn off usage accounting without turning off limits, or 1885 * suspend quotas and simultaneously turn quotas off. */ 1886 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 1887 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 1888 DQUOT_USAGE_ENABLED))) 1889 return -EINVAL; 1890 1891 /* We need to serialize quota_off() for device */ 1892 mutex_lock(&dqopt->dqonoff_mutex); 1893 1894 /* 1895 * Skip everything if there's nothing to do. We have to do this because 1896 * sometimes we are called when fill_super() failed and calling 1897 * sync_fs() in such cases does no good. 1898 */ 1899 if (!sb_any_quota_loaded(sb)) { 1900 mutex_unlock(&dqopt->dqonoff_mutex); 1901 return 0; 1902 } 1903 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1904 toputinode[cnt] = NULL; 1905 if (type != -1 && cnt != type) 1906 continue; 1907 if (!sb_has_quota_loaded(sb, cnt)) 1908 continue; 1909 1910 if (flags & DQUOT_SUSPENDED) { 1911 spin_lock(&dq_state_lock); 1912 dqopt->flags |= 1913 dquot_state_flag(DQUOT_SUSPENDED, cnt); 1914 spin_unlock(&dq_state_lock); 1915 } else { 1916 spin_lock(&dq_state_lock); 1917 dqopt->flags &= ~dquot_state_flag(flags, cnt); 1918 /* Turning off suspended quotas? */ 1919 if (!sb_has_quota_loaded(sb, cnt) && 1920 sb_has_quota_suspended(sb, cnt)) { 1921 dqopt->flags &= ~dquot_state_flag( 1922 DQUOT_SUSPENDED, cnt); 1923 spin_unlock(&dq_state_lock); 1924 iput(dqopt->files[cnt]); 1925 dqopt->files[cnt] = NULL; 1926 continue; 1927 } 1928 spin_unlock(&dq_state_lock); 1929 } 1930 1931 /* We still have to keep quota loaded? */ 1932 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 1933 continue; 1934 1935 /* Note: these are blocking operations */ 1936 drop_dquot_ref(sb, cnt); 1937 invalidate_dquots(sb, cnt); 1938 /* 1939 * Now all dquots should be invalidated, all writes done so we 1940 * should be only users of the info. No locks needed. 1941 */ 1942 if (info_dirty(&dqopt->info[cnt])) 1943 sb->dq_op->write_info(sb, cnt); 1944 if (dqopt->ops[cnt]->free_file_info) 1945 dqopt->ops[cnt]->free_file_info(sb, cnt); 1946 put_quota_format(dqopt->info[cnt].dqi_format); 1947 1948 toputinode[cnt] = dqopt->files[cnt]; 1949 if (!sb_has_quota_loaded(sb, cnt)) 1950 dqopt->files[cnt] = NULL; 1951 dqopt->info[cnt].dqi_flags = 0; 1952 dqopt->info[cnt].dqi_igrace = 0; 1953 dqopt->info[cnt].dqi_bgrace = 0; 1954 dqopt->ops[cnt] = NULL; 1955 } 1956 mutex_unlock(&dqopt->dqonoff_mutex); 1957 1958 /* Skip syncing and setting flags if quota files are hidden */ 1959 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 1960 goto put_inodes; 1961 1962 /* Sync the superblock so that buffers with quota data are written to 1963 * disk (and so userspace sees correct data afterwards). */ 1964 if (sb->s_op->sync_fs) 1965 sb->s_op->sync_fs(sb, 1); 1966 sync_blockdev(sb->s_bdev); 1967 /* Now the quota files are just ordinary files and we can set the 1968 * inode flags back. Moreover we discard the pagecache so that 1969 * userspace sees the writes we did bypassing the pagecache. We 1970 * must also discard the blockdev buffers so that we see the 1971 * changes done by userspace on the next quotaon() */ 1972 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1973 if (toputinode[cnt]) { 1974 mutex_lock(&dqopt->dqonoff_mutex); 1975 /* If quota was reenabled in the meantime, we have 1976 * nothing to do */ 1977 if (!sb_has_quota_loaded(sb, cnt)) { 1978 mutex_lock_nested(&toputinode[cnt]->i_mutex, 1979 I_MUTEX_QUOTA); 1980 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 1981 S_NOATIME | S_NOQUOTA); 1982 truncate_inode_pages(&toputinode[cnt]->i_data, 1983 0); 1984 mutex_unlock(&toputinode[cnt]->i_mutex); 1985 mark_inode_dirty(toputinode[cnt]); 1986 } 1987 mutex_unlock(&dqopt->dqonoff_mutex); 1988 } 1989 if (sb->s_bdev) 1990 invalidate_bdev(sb->s_bdev); 1991 put_inodes: 1992 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1993 if (toputinode[cnt]) { 1994 /* On remount RO, we keep the inode pointer so that we 1995 * can reenable quota on the subsequent remount RW. We 1996 * have to check 'flags' variable and not use sb_has_ 1997 * function because another quotaon / quotaoff could 1998 * change global state before we got here. We refuse 1999 * to suspend quotas when there is pending delete on 2000 * the quota file... */ 2001 if (!(flags & DQUOT_SUSPENDED)) 2002 iput(toputinode[cnt]); 2003 else if (!toputinode[cnt]->i_nlink) 2004 ret = -EBUSY; 2005 } 2006 return ret; 2007 } 2008 EXPORT_SYMBOL(vfs_quota_disable); 2009 2010 int vfs_quota_off(struct super_block *sb, int type, int remount) 2011 { 2012 return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED : 2013 (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED)); 2014 } 2015 EXPORT_SYMBOL(vfs_quota_off); 2016 /* 2017 * Turn quotas on on a device 2018 */ 2019 2020 /* 2021 * Helper function to turn quotas on when we already have the inode of 2022 * quota file and no quota information is loaded. 2023 */ 2024 static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 2025 unsigned int flags) 2026 { 2027 struct quota_format_type *fmt = find_quota_format(format_id); 2028 struct super_block *sb = inode->i_sb; 2029 struct quota_info *dqopt = sb_dqopt(sb); 2030 int error; 2031 int oldflags = -1; 2032 2033 if (!fmt) 2034 return -ESRCH; 2035 if (!S_ISREG(inode->i_mode)) { 2036 error = -EACCES; 2037 goto out_fmt; 2038 } 2039 if (IS_RDONLY(inode)) { 2040 error = -EROFS; 2041 goto out_fmt; 2042 } 2043 if (!sb->s_op->quota_write || !sb->s_op->quota_read) { 2044 error = -EINVAL; 2045 goto out_fmt; 2046 } 2047 /* Usage always has to be set... */ 2048 if (!(flags & DQUOT_USAGE_ENABLED)) { 2049 error = -EINVAL; 2050 goto out_fmt; 2051 } 2052 2053 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2054 /* As we bypass the pagecache we must now flush all the 2055 * dirty data and invalidate caches so that kernel sees 2056 * changes from userspace. It is not enough to just flush 2057 * the quota file since if blocksize < pagesize, invalidation 2058 * of the cache could fail because of other unrelated dirty 2059 * data */ 2060 sync_filesystem(sb); 2061 invalidate_bdev(sb->s_bdev); 2062 } 2063 mutex_lock(&dqopt->dqonoff_mutex); 2064 if (sb_has_quota_loaded(sb, type)) { 2065 error = -EBUSY; 2066 goto out_lock; 2067 } 2068 2069 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2070 /* We don't want quota and atime on quota files (deadlocks 2071 * possible) Also nobody should write to the file - we use 2072 * special IO operations which ignore the immutable bit. */ 2073 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2074 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2075 S_NOQUOTA); 2076 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2077 mutex_unlock(&inode->i_mutex); 2078 /* 2079 * When S_NOQUOTA is set, remove dquot references as no more 2080 * references can be added 2081 */ 2082 __dquot_drop(inode); 2083 } 2084 2085 error = -EIO; 2086 dqopt->files[type] = igrab(inode); 2087 if (!dqopt->files[type]) 2088 goto out_lock; 2089 error = -EINVAL; 2090 if (!fmt->qf_ops->check_quota_file(sb, type)) 2091 goto out_file_init; 2092 2093 dqopt->ops[type] = fmt->qf_ops; 2094 dqopt->info[type].dqi_format = fmt; 2095 dqopt->info[type].dqi_fmt_id = format_id; 2096 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2097 mutex_lock(&dqopt->dqio_mutex); 2098 error = dqopt->ops[type]->read_file_info(sb, type); 2099 if (error < 0) { 2100 mutex_unlock(&dqopt->dqio_mutex); 2101 goto out_file_init; 2102 } 2103 mutex_unlock(&dqopt->dqio_mutex); 2104 spin_lock(&dq_state_lock); 2105 dqopt->flags |= dquot_state_flag(flags, type); 2106 spin_unlock(&dq_state_lock); 2107 2108 add_dquot_ref(sb, type); 2109 mutex_unlock(&dqopt->dqonoff_mutex); 2110 2111 return 0; 2112 2113 out_file_init: 2114 dqopt->files[type] = NULL; 2115 iput(inode); 2116 out_lock: 2117 if (oldflags != -1) { 2118 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2119 /* Set the flags back (in the case of accidental quotaon() 2120 * on a wrong file we don't want to mess up the flags) */ 2121 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2122 inode->i_flags |= oldflags; 2123 mutex_unlock(&inode->i_mutex); 2124 } 2125 mutex_unlock(&dqopt->dqonoff_mutex); 2126 out_fmt: 2127 put_quota_format(fmt); 2128 2129 return error; 2130 } 2131 2132 /* Reenable quotas on remount RW */ 2133 static int vfs_quota_on_remount(struct super_block *sb, int type) 2134 { 2135 struct quota_info *dqopt = sb_dqopt(sb); 2136 struct inode *inode; 2137 int ret; 2138 unsigned int flags; 2139 2140 mutex_lock(&dqopt->dqonoff_mutex); 2141 if (!sb_has_quota_suspended(sb, type)) { 2142 mutex_unlock(&dqopt->dqonoff_mutex); 2143 return 0; 2144 } 2145 inode = dqopt->files[type]; 2146 dqopt->files[type] = NULL; 2147 spin_lock(&dq_state_lock); 2148 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2149 DQUOT_LIMITS_ENABLED, type); 2150 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type); 2151 spin_unlock(&dq_state_lock); 2152 mutex_unlock(&dqopt->dqonoff_mutex); 2153 2154 flags = dquot_generic_flag(flags, type); 2155 ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id, 2156 flags); 2157 iput(inode); 2158 2159 return ret; 2160 } 2161 2162 int vfs_quota_on_path(struct super_block *sb, int type, int format_id, 2163 struct path *path) 2164 { 2165 int error = security_quota_on(path->dentry); 2166 if (error) 2167 return error; 2168 /* Quota file not on the same filesystem? */ 2169 if (path->mnt->mnt_sb != sb) 2170 error = -EXDEV; 2171 else 2172 error = vfs_load_quota_inode(path->dentry->d_inode, type, 2173 format_id, DQUOT_USAGE_ENABLED | 2174 DQUOT_LIMITS_ENABLED); 2175 return error; 2176 } 2177 EXPORT_SYMBOL(vfs_quota_on_path); 2178 2179 int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name, 2180 int remount) 2181 { 2182 struct path path; 2183 int error; 2184 2185 if (remount) 2186 return vfs_quota_on_remount(sb, type); 2187 2188 error = kern_path(name, LOOKUP_FOLLOW, &path); 2189 if (!error) { 2190 error = vfs_quota_on_path(sb, type, format_id, &path); 2191 path_put(&path); 2192 } 2193 return error; 2194 } 2195 EXPORT_SYMBOL(vfs_quota_on); 2196 2197 /* 2198 * More powerful function for turning on quotas allowing setting 2199 * of individual quota flags 2200 */ 2201 int vfs_quota_enable(struct inode *inode, int type, int format_id, 2202 unsigned int flags) 2203 { 2204 int ret = 0; 2205 struct super_block *sb = inode->i_sb; 2206 struct quota_info *dqopt = sb_dqopt(sb); 2207 2208 /* Just unsuspend quotas? */ 2209 if (flags & DQUOT_SUSPENDED) 2210 return vfs_quota_on_remount(sb, type); 2211 if (!flags) 2212 return 0; 2213 /* Just updating flags needed? */ 2214 if (sb_has_quota_loaded(sb, type)) { 2215 mutex_lock(&dqopt->dqonoff_mutex); 2216 /* Now do a reliable test... */ 2217 if (!sb_has_quota_loaded(sb, type)) { 2218 mutex_unlock(&dqopt->dqonoff_mutex); 2219 goto load_quota; 2220 } 2221 if (flags & DQUOT_USAGE_ENABLED && 2222 sb_has_quota_usage_enabled(sb, type)) { 2223 ret = -EBUSY; 2224 goto out_lock; 2225 } 2226 if (flags & DQUOT_LIMITS_ENABLED && 2227 sb_has_quota_limits_enabled(sb, type)) { 2228 ret = -EBUSY; 2229 goto out_lock; 2230 } 2231 spin_lock(&dq_state_lock); 2232 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2233 spin_unlock(&dq_state_lock); 2234 out_lock: 2235 mutex_unlock(&dqopt->dqonoff_mutex); 2236 return ret; 2237 } 2238 2239 load_quota: 2240 return vfs_load_quota_inode(inode, type, format_id, flags); 2241 } 2242 EXPORT_SYMBOL(vfs_quota_enable); 2243 2244 /* 2245 * This function is used when filesystem needs to initialize quotas 2246 * during mount time. 2247 */ 2248 int vfs_quota_on_mount(struct super_block *sb, char *qf_name, 2249 int format_id, int type) 2250 { 2251 struct dentry *dentry; 2252 int error; 2253 2254 mutex_lock(&sb->s_root->d_inode->i_mutex); 2255 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2256 mutex_unlock(&sb->s_root->d_inode->i_mutex); 2257 if (IS_ERR(dentry)) 2258 return PTR_ERR(dentry); 2259 2260 if (!dentry->d_inode) { 2261 error = -ENOENT; 2262 goto out; 2263 } 2264 2265 error = security_quota_on(dentry); 2266 if (!error) 2267 error = vfs_load_quota_inode(dentry->d_inode, type, format_id, 2268 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2269 2270 out: 2271 dput(dentry); 2272 return error; 2273 } 2274 EXPORT_SYMBOL(vfs_quota_on_mount); 2275 2276 /* Wrapper to turn on quotas when remounting rw */ 2277 int vfs_dq_quota_on_remount(struct super_block *sb) 2278 { 2279 int cnt; 2280 int ret = 0, err; 2281 2282 if (!sb->s_qcop || !sb->s_qcop->quota_on) 2283 return -ENOSYS; 2284 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2285 err = sb->s_qcop->quota_on(sb, cnt, 0, NULL, 1); 2286 if (err < 0 && !ret) 2287 ret = err; 2288 } 2289 return ret; 2290 } 2291 EXPORT_SYMBOL(vfs_dq_quota_on_remount); 2292 2293 static inline qsize_t qbtos(qsize_t blocks) 2294 { 2295 return blocks << QIF_DQBLKSIZE_BITS; 2296 } 2297 2298 static inline qsize_t stoqb(qsize_t space) 2299 { 2300 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; 2301 } 2302 2303 /* Generic routine for getting common part of quota structure */ 2304 static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di) 2305 { 2306 struct mem_dqblk *dm = &dquot->dq_dqb; 2307 2308 spin_lock(&dq_data_lock); 2309 di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit); 2310 di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit); 2311 di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace; 2312 di->dqb_ihardlimit = dm->dqb_ihardlimit; 2313 di->dqb_isoftlimit = dm->dqb_isoftlimit; 2314 di->dqb_curinodes = dm->dqb_curinodes; 2315 di->dqb_btime = dm->dqb_btime; 2316 di->dqb_itime = dm->dqb_itime; 2317 di->dqb_valid = QIF_ALL; 2318 spin_unlock(&dq_data_lock); 2319 } 2320 2321 int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, 2322 struct if_dqblk *di) 2323 { 2324 struct dquot *dquot; 2325 2326 dquot = dqget(sb, id, type); 2327 if (!dquot) 2328 return -ESRCH; 2329 do_get_dqblk(dquot, di); 2330 dqput(dquot); 2331 2332 return 0; 2333 } 2334 EXPORT_SYMBOL(vfs_get_dqblk); 2335 2336 /* Generic routine for setting common part of quota structure */ 2337 static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di) 2338 { 2339 struct mem_dqblk *dm = &dquot->dq_dqb; 2340 int check_blim = 0, check_ilim = 0; 2341 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 2342 2343 if ((di->dqb_valid & QIF_BLIMITS && 2344 (di->dqb_bhardlimit > dqi->dqi_maxblimit || 2345 di->dqb_bsoftlimit > dqi->dqi_maxblimit)) || 2346 (di->dqb_valid & QIF_ILIMITS && 2347 (di->dqb_ihardlimit > dqi->dqi_maxilimit || 2348 di->dqb_isoftlimit > dqi->dqi_maxilimit))) 2349 return -ERANGE; 2350 2351 spin_lock(&dq_data_lock); 2352 if (di->dqb_valid & QIF_SPACE) { 2353 dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace; 2354 check_blim = 1; 2355 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2356 } 2357 if (di->dqb_valid & QIF_BLIMITS) { 2358 dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit); 2359 dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit); 2360 check_blim = 1; 2361 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2362 } 2363 if (di->dqb_valid & QIF_INODES) { 2364 dm->dqb_curinodes = di->dqb_curinodes; 2365 check_ilim = 1; 2366 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2367 } 2368 if (di->dqb_valid & QIF_ILIMITS) { 2369 dm->dqb_isoftlimit = di->dqb_isoftlimit; 2370 dm->dqb_ihardlimit = di->dqb_ihardlimit; 2371 check_ilim = 1; 2372 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2373 } 2374 if (di->dqb_valid & QIF_BTIME) { 2375 dm->dqb_btime = di->dqb_btime; 2376 check_blim = 1; 2377 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2378 } 2379 if (di->dqb_valid & QIF_ITIME) { 2380 dm->dqb_itime = di->dqb_itime; 2381 check_ilim = 1; 2382 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2383 } 2384 2385 if (check_blim) { 2386 if (!dm->dqb_bsoftlimit || 2387 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2388 dm->dqb_btime = 0; 2389 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2390 } else if (!(di->dqb_valid & QIF_BTIME)) 2391 /* Set grace only if user hasn't provided his own... */ 2392 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2393 } 2394 if (check_ilim) { 2395 if (!dm->dqb_isoftlimit || 2396 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2397 dm->dqb_itime = 0; 2398 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2399 } else if (!(di->dqb_valid & QIF_ITIME)) 2400 /* Set grace only if user hasn't provided his own... */ 2401 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2402 } 2403 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2404 dm->dqb_isoftlimit) 2405 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2406 else 2407 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2408 spin_unlock(&dq_data_lock); 2409 mark_dquot_dirty(dquot); 2410 2411 return 0; 2412 } 2413 2414 int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, 2415 struct if_dqblk *di) 2416 { 2417 struct dquot *dquot; 2418 int rc; 2419 2420 dquot = dqget(sb, id, type); 2421 if (!dquot) { 2422 rc = -ESRCH; 2423 goto out; 2424 } 2425 rc = do_set_dqblk(dquot, di); 2426 dqput(dquot); 2427 out: 2428 return rc; 2429 } 2430 EXPORT_SYMBOL(vfs_set_dqblk); 2431 2432 /* Generic routine for getting common part of quota file information */ 2433 int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2434 { 2435 struct mem_dqinfo *mi; 2436 2437 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2438 if (!sb_has_quota_active(sb, type)) { 2439 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2440 return -ESRCH; 2441 } 2442 mi = sb_dqopt(sb)->info + type; 2443 spin_lock(&dq_data_lock); 2444 ii->dqi_bgrace = mi->dqi_bgrace; 2445 ii->dqi_igrace = mi->dqi_igrace; 2446 ii->dqi_flags = mi->dqi_flags & DQF_MASK; 2447 ii->dqi_valid = IIF_ALL; 2448 spin_unlock(&dq_data_lock); 2449 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2450 return 0; 2451 } 2452 EXPORT_SYMBOL(vfs_get_dqinfo); 2453 2454 /* Generic routine for setting common part of quota file information */ 2455 int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2456 { 2457 struct mem_dqinfo *mi; 2458 int err = 0; 2459 2460 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2461 if (!sb_has_quota_active(sb, type)) { 2462 err = -ESRCH; 2463 goto out; 2464 } 2465 mi = sb_dqopt(sb)->info + type; 2466 spin_lock(&dq_data_lock); 2467 if (ii->dqi_valid & IIF_BGRACE) 2468 mi->dqi_bgrace = ii->dqi_bgrace; 2469 if (ii->dqi_valid & IIF_IGRACE) 2470 mi->dqi_igrace = ii->dqi_igrace; 2471 if (ii->dqi_valid & IIF_FLAGS) 2472 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | 2473 (ii->dqi_flags & DQF_MASK); 2474 spin_unlock(&dq_data_lock); 2475 mark_info_dirty(sb, type); 2476 /* Force write to disk */ 2477 sb->dq_op->write_info(sb, type); 2478 out: 2479 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2480 return err; 2481 } 2482 EXPORT_SYMBOL(vfs_set_dqinfo); 2483 2484 const struct quotactl_ops vfs_quotactl_ops = { 2485 .quota_on = vfs_quota_on, 2486 .quota_off = vfs_quota_off, 2487 .quota_sync = vfs_quota_sync, 2488 .get_info = vfs_get_dqinfo, 2489 .set_info = vfs_set_dqinfo, 2490 .get_dqblk = vfs_get_dqblk, 2491 .set_dqblk = vfs_set_dqblk 2492 }; 2493 2494 2495 static int do_proc_dqstats(struct ctl_table *table, int write, 2496 void __user *buffer, size_t *lenp, loff_t *ppos) 2497 { 2498 #ifdef CONFIG_SMP 2499 /* Update global table */ 2500 unsigned int type = (int *)table->data - dqstats.stat; 2501 dqstats.stat[type] = dqstats_read(type); 2502 #endif 2503 return proc_dointvec(table, write, buffer, lenp, ppos); 2504 } 2505 2506 static ctl_table fs_dqstats_table[] = { 2507 { 2508 .procname = "lookups", 2509 .data = &dqstats.stat[DQST_LOOKUPS], 2510 .maxlen = sizeof(int), 2511 .mode = 0444, 2512 .proc_handler = do_proc_dqstats, 2513 }, 2514 { 2515 .procname = "drops", 2516 .data = &dqstats.stat[DQST_DROPS], 2517 .maxlen = sizeof(int), 2518 .mode = 0444, 2519 .proc_handler = do_proc_dqstats, 2520 }, 2521 { 2522 .procname = "reads", 2523 .data = &dqstats.stat[DQST_READS], 2524 .maxlen = sizeof(int), 2525 .mode = 0444, 2526 .proc_handler = do_proc_dqstats, 2527 }, 2528 { 2529 .procname = "writes", 2530 .data = &dqstats.stat[DQST_WRITES], 2531 .maxlen = sizeof(int), 2532 .mode = 0444, 2533 .proc_handler = do_proc_dqstats, 2534 }, 2535 { 2536 .procname = "cache_hits", 2537 .data = &dqstats.stat[DQST_CACHE_HITS], 2538 .maxlen = sizeof(int), 2539 .mode = 0444, 2540 .proc_handler = do_proc_dqstats, 2541 }, 2542 { 2543 .procname = "allocated_dquots", 2544 .data = &dqstats.stat[DQST_ALLOC_DQUOTS], 2545 .maxlen = sizeof(int), 2546 .mode = 0444, 2547 .proc_handler = do_proc_dqstats, 2548 }, 2549 { 2550 .procname = "free_dquots", 2551 .data = &dqstats.stat[DQST_FREE_DQUOTS], 2552 .maxlen = sizeof(int), 2553 .mode = 0444, 2554 .proc_handler = do_proc_dqstats, 2555 }, 2556 { 2557 .procname = "syncs", 2558 .data = &dqstats.stat[DQST_SYNCS], 2559 .maxlen = sizeof(int), 2560 .mode = 0444, 2561 .proc_handler = do_proc_dqstats, 2562 }, 2563 #ifdef CONFIG_PRINT_QUOTA_WARNING 2564 { 2565 .procname = "warnings", 2566 .data = &flag_print_warnings, 2567 .maxlen = sizeof(int), 2568 .mode = 0644, 2569 .proc_handler = proc_dointvec, 2570 }, 2571 #endif 2572 { }, 2573 }; 2574 2575 static ctl_table fs_table[] = { 2576 { 2577 .procname = "quota", 2578 .mode = 0555, 2579 .child = fs_dqstats_table, 2580 }, 2581 { }, 2582 }; 2583 2584 static ctl_table sys_table[] = { 2585 { 2586 .procname = "fs", 2587 .mode = 0555, 2588 .child = fs_table, 2589 }, 2590 { }, 2591 }; 2592 2593 static int __init dquot_init(void) 2594 { 2595 int i; 2596 unsigned long nr_hash, order; 2597 2598 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2599 2600 register_sysctl_table(sys_table); 2601 2602 dquot_cachep = kmem_cache_create("dquot", 2603 sizeof(struct dquot), sizeof(unsigned long) * 4, 2604 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2605 SLAB_MEM_SPREAD|SLAB_PANIC), 2606 NULL); 2607 2608 order = 0; 2609 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2610 if (!dquot_hash) 2611 panic("Cannot create dquot hash table"); 2612 2613 #ifdef CONFIG_SMP 2614 dqstats_pcpu = alloc_percpu(struct dqstats); 2615 if (!dqstats_pcpu) 2616 panic("Cannot create dquot stats table"); 2617 #endif 2618 memset(&dqstats, 0, sizeof(struct dqstats)); 2619 2620 /* Find power-of-two hlist_heads which can fit into allocation */ 2621 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2622 dq_hash_bits = 0; 2623 do { 2624 dq_hash_bits++; 2625 } while (nr_hash >> dq_hash_bits); 2626 dq_hash_bits--; 2627 2628 nr_hash = 1UL << dq_hash_bits; 2629 dq_hash_mask = nr_hash - 1; 2630 for (i = 0; i < nr_hash; i++) 2631 INIT_HLIST_HEAD(dquot_hash + i); 2632 2633 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", 2634 nr_hash, order, (PAGE_SIZE << order)); 2635 2636 register_shrinker(&dqcache_shrinker); 2637 2638 return 0; 2639 } 2640 module_init(dquot_init); 2641