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/sched.h> 75 #include <linux/cred.h> 76 #include <linux/kmod.h> 77 #include <linux/namei.h> 78 #include <linux/capability.h> 79 #include <linux/quotaops.h> 80 #include "../internal.h" /* ugh */ 81 82 #include <linux/uaccess.h> 83 84 /* 85 * There are three quota SMP locks. dq_list_lock protects all lists with quotas 86 * and quota formats. 87 * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and 88 * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes. 89 * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly 90 * in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects 91 * modifications of quota state (on quotaon and quotaoff) and readers who care 92 * about latest values take it as well. 93 * 94 * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock, 95 * dq_list_lock > dq_state_lock 96 * 97 * Note that some things (eg. sb pointer, type, id) doesn't change during 98 * the life of the dquot structure and so needn't to be protected by a lock 99 * 100 * Operation accessing dquots via inode pointers are protected by dquot_srcu. 101 * Operation of reading pointer needs srcu_read_lock(&dquot_srcu), and 102 * synchronize_srcu(&dquot_srcu) is called after clearing pointers from 103 * inode and before dropping dquot references to avoid use of dquots after 104 * they are freed. dq_data_lock is used to serialize the pointer setting and 105 * clearing operations. 106 * Special care needs to be taken about S_NOQUOTA inode flag (marking that 107 * inode is a quota file). Functions adding pointers from inode to dquots have 108 * to check this flag under dq_data_lock and then (if S_NOQUOTA is not set) they 109 * have to do all pointer modifications before dropping dq_data_lock. This makes 110 * sure they cannot race with quotaon which first sets S_NOQUOTA flag and 111 * then drops all pointers to dquots from an inode. 112 * 113 * Each dquot has its dq_lock mutex. Locked dquots might not be referenced 114 * from inodes (dquot_alloc_space() and such don't check the dq_lock). 115 * Currently dquot is locked only when it is being read to memory (or space for 116 * it is being allocated) on the first dqget() and when it is being released on 117 * the last dqput(). The allocation and release oparations are serialized by 118 * the dq_lock and by checking the use count in dquot_release(). Write 119 * operations on dquots don't hold dq_lock as they copy data under dq_data_lock 120 * spinlock to internal buffers before writing. 121 * 122 * Lock ordering (including related VFS locks) is the following: 123 * s_umount > i_mutex > journal_lock > dquot->dq_lock > dqio_mutex 124 */ 125 126 static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock); 127 static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock); 128 __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock); 129 EXPORT_SYMBOL(dq_data_lock); 130 DEFINE_STATIC_SRCU(dquot_srcu); 131 132 void __quota_error(struct super_block *sb, const char *func, 133 const char *fmt, ...) 134 { 135 if (printk_ratelimit()) { 136 va_list args; 137 struct va_format vaf; 138 139 va_start(args, fmt); 140 141 vaf.fmt = fmt; 142 vaf.va = &args; 143 144 printk(KERN_ERR "Quota error (device %s): %s: %pV\n", 145 sb->s_id, func, &vaf); 146 147 va_end(args); 148 } 149 } 150 EXPORT_SYMBOL(__quota_error); 151 152 #if defined(CONFIG_QUOTA_DEBUG) || defined(CONFIG_PRINT_QUOTA_WARNING) 153 static char *quotatypes[] = INITQFNAMES; 154 #endif 155 static struct quota_format_type *quota_formats; /* List of registered formats */ 156 static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES; 157 158 /* SLAB cache for dquot structures */ 159 static struct kmem_cache *dquot_cachep; 160 161 int register_quota_format(struct quota_format_type *fmt) 162 { 163 spin_lock(&dq_list_lock); 164 fmt->qf_next = quota_formats; 165 quota_formats = fmt; 166 spin_unlock(&dq_list_lock); 167 return 0; 168 } 169 EXPORT_SYMBOL(register_quota_format); 170 171 void unregister_quota_format(struct quota_format_type *fmt) 172 { 173 struct quota_format_type **actqf; 174 175 spin_lock(&dq_list_lock); 176 for (actqf = "a_formats; *actqf && *actqf != fmt; 177 actqf = &(*actqf)->qf_next) 178 ; 179 if (*actqf) 180 *actqf = (*actqf)->qf_next; 181 spin_unlock(&dq_list_lock); 182 } 183 EXPORT_SYMBOL(unregister_quota_format); 184 185 static struct quota_format_type *find_quota_format(int id) 186 { 187 struct quota_format_type *actqf; 188 189 spin_lock(&dq_list_lock); 190 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; 191 actqf = actqf->qf_next) 192 ; 193 if (!actqf || !try_module_get(actqf->qf_owner)) { 194 int qm; 195 196 spin_unlock(&dq_list_lock); 197 198 for (qm = 0; module_names[qm].qm_fmt_id && 199 module_names[qm].qm_fmt_id != id; qm++) 200 ; 201 if (!module_names[qm].qm_fmt_id || 202 request_module(module_names[qm].qm_mod_name)) 203 return NULL; 204 205 spin_lock(&dq_list_lock); 206 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; 207 actqf = actqf->qf_next) 208 ; 209 if (actqf && !try_module_get(actqf->qf_owner)) 210 actqf = NULL; 211 } 212 spin_unlock(&dq_list_lock); 213 return actqf; 214 } 215 216 static void put_quota_format(struct quota_format_type *fmt) 217 { 218 module_put(fmt->qf_owner); 219 } 220 221 /* 222 * Dquot List Management: 223 * The quota code uses three lists for dquot management: the inuse_list, 224 * free_dquots, and dquot_hash[] array. A single dquot structure may be 225 * on all three lists, depending on its current state. 226 * 227 * All dquots are placed to the end of inuse_list when first created, and this 228 * list is used for invalidate operation, which must look at every dquot. 229 * 230 * Unused dquots (dq_count == 0) are added to the free_dquots list when freed, 231 * and this list is searched whenever we need an available dquot. Dquots are 232 * removed from the list as soon as they are used again, and 233 * dqstats.free_dquots gives the number of dquots on the list. When 234 * dquot is invalidated it's completely released from memory. 235 * 236 * Dquots with a specific identity (device, type and id) are placed on 237 * one of the dquot_hash[] hash chains. The provides an efficient search 238 * mechanism to locate a specific dquot. 239 */ 240 241 static LIST_HEAD(inuse_list); 242 static LIST_HEAD(free_dquots); 243 static unsigned int dq_hash_bits, dq_hash_mask; 244 static struct hlist_head *dquot_hash; 245 246 struct dqstats dqstats; 247 EXPORT_SYMBOL(dqstats); 248 249 static qsize_t inode_get_rsv_space(struct inode *inode); 250 static int __dquot_initialize(struct inode *inode, int type); 251 252 static inline unsigned int 253 hashfn(const struct super_block *sb, struct kqid qid) 254 { 255 unsigned int id = from_kqid(&init_user_ns, qid); 256 int type = qid.type; 257 unsigned long tmp; 258 259 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type); 260 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask; 261 } 262 263 /* 264 * Following list functions expect dq_list_lock to be held 265 */ 266 static inline void insert_dquot_hash(struct dquot *dquot) 267 { 268 struct hlist_head *head; 269 head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id); 270 hlist_add_head(&dquot->dq_hash, head); 271 } 272 273 static inline void remove_dquot_hash(struct dquot *dquot) 274 { 275 hlist_del_init(&dquot->dq_hash); 276 } 277 278 static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, 279 struct kqid qid) 280 { 281 struct hlist_node *node; 282 struct dquot *dquot; 283 284 hlist_for_each (node, dquot_hash+hashent) { 285 dquot = hlist_entry(node, struct dquot, dq_hash); 286 if (dquot->dq_sb == sb && qid_eq(dquot->dq_id, qid)) 287 return dquot; 288 } 289 return NULL; 290 } 291 292 /* Add a dquot to the tail of the free list */ 293 static inline void put_dquot_last(struct dquot *dquot) 294 { 295 list_add_tail(&dquot->dq_free, &free_dquots); 296 dqstats_inc(DQST_FREE_DQUOTS); 297 } 298 299 static inline void remove_free_dquot(struct dquot *dquot) 300 { 301 if (list_empty(&dquot->dq_free)) 302 return; 303 list_del_init(&dquot->dq_free); 304 dqstats_dec(DQST_FREE_DQUOTS); 305 } 306 307 static inline void put_inuse(struct dquot *dquot) 308 { 309 /* We add to the back of inuse list so we don't have to restart 310 * when traversing this list and we block */ 311 list_add_tail(&dquot->dq_inuse, &inuse_list); 312 dqstats_inc(DQST_ALLOC_DQUOTS); 313 } 314 315 static inline void remove_inuse(struct dquot *dquot) 316 { 317 dqstats_dec(DQST_ALLOC_DQUOTS); 318 list_del(&dquot->dq_inuse); 319 } 320 /* 321 * End of list functions needing dq_list_lock 322 */ 323 324 static void wait_on_dquot(struct dquot *dquot) 325 { 326 mutex_lock(&dquot->dq_lock); 327 mutex_unlock(&dquot->dq_lock); 328 } 329 330 static inline int dquot_dirty(struct dquot *dquot) 331 { 332 return test_bit(DQ_MOD_B, &dquot->dq_flags); 333 } 334 335 static inline int mark_dquot_dirty(struct dquot *dquot) 336 { 337 return dquot->dq_sb->dq_op->mark_dirty(dquot); 338 } 339 340 /* Mark dquot dirty in atomic manner, and return it's old dirty flag state */ 341 int dquot_mark_dquot_dirty(struct dquot *dquot) 342 { 343 int ret = 1; 344 345 /* If quota is dirty already, we don't have to acquire dq_list_lock */ 346 if (test_bit(DQ_MOD_B, &dquot->dq_flags)) 347 return 1; 348 349 spin_lock(&dq_list_lock); 350 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) { 351 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)-> 352 info[dquot->dq_id.type].dqi_dirty_list); 353 ret = 0; 354 } 355 spin_unlock(&dq_list_lock); 356 return ret; 357 } 358 EXPORT_SYMBOL(dquot_mark_dquot_dirty); 359 360 /* Dirtify all the dquots - this can block when journalling */ 361 static inline int mark_all_dquot_dirty(struct dquot * const *dquot) 362 { 363 int ret, err, cnt; 364 365 ret = err = 0; 366 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 367 if (dquot[cnt]) 368 /* Even in case of error we have to continue */ 369 ret = mark_dquot_dirty(dquot[cnt]); 370 if (!err) 371 err = ret; 372 } 373 return err; 374 } 375 376 static inline void dqput_all(struct dquot **dquot) 377 { 378 unsigned int cnt; 379 380 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 381 dqput(dquot[cnt]); 382 } 383 384 /* This function needs dq_list_lock */ 385 static inline int clear_dquot_dirty(struct dquot *dquot) 386 { 387 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) 388 return 0; 389 list_del_init(&dquot->dq_dirty); 390 return 1; 391 } 392 393 void mark_info_dirty(struct super_block *sb, int type) 394 { 395 set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags); 396 } 397 EXPORT_SYMBOL(mark_info_dirty); 398 399 /* 400 * Read dquot from disk and alloc space for it 401 */ 402 403 int dquot_acquire(struct dquot *dquot) 404 { 405 int ret = 0, ret2 = 0; 406 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 407 408 mutex_lock(&dquot->dq_lock); 409 mutex_lock(&dqopt->dqio_mutex); 410 if (!test_bit(DQ_READ_B, &dquot->dq_flags)) 411 ret = dqopt->ops[dquot->dq_id.type]->read_dqblk(dquot); 412 if (ret < 0) 413 goto out_iolock; 414 /* Make sure flags update is visible after dquot has been filled */ 415 smp_mb__before_atomic(); 416 set_bit(DQ_READ_B, &dquot->dq_flags); 417 /* Instantiate dquot if needed */ 418 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) { 419 ret = dqopt->ops[dquot->dq_id.type]->commit_dqblk(dquot); 420 /* Write the info if needed */ 421 if (info_dirty(&dqopt->info[dquot->dq_id.type])) { 422 ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info( 423 dquot->dq_sb, dquot->dq_id.type); 424 } 425 if (ret < 0) 426 goto out_iolock; 427 if (ret2 < 0) { 428 ret = ret2; 429 goto out_iolock; 430 } 431 } 432 /* 433 * Make sure flags update is visible after on-disk struct has been 434 * allocated. Paired with smp_rmb() in dqget(). 435 */ 436 smp_mb__before_atomic(); 437 set_bit(DQ_ACTIVE_B, &dquot->dq_flags); 438 out_iolock: 439 mutex_unlock(&dqopt->dqio_mutex); 440 mutex_unlock(&dquot->dq_lock); 441 return ret; 442 } 443 EXPORT_SYMBOL(dquot_acquire); 444 445 /* 446 * Write dquot to disk 447 */ 448 int dquot_commit(struct dquot *dquot) 449 { 450 int ret = 0; 451 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 452 453 mutex_lock(&dqopt->dqio_mutex); 454 spin_lock(&dq_list_lock); 455 if (!clear_dquot_dirty(dquot)) { 456 spin_unlock(&dq_list_lock); 457 goto out_sem; 458 } 459 spin_unlock(&dq_list_lock); 460 /* Inactive dquot can be only if there was error during read/init 461 * => we have better not writing it */ 462 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) 463 ret = dqopt->ops[dquot->dq_id.type]->commit_dqblk(dquot); 464 else 465 ret = -EIO; 466 out_sem: 467 mutex_unlock(&dqopt->dqio_mutex); 468 return ret; 469 } 470 EXPORT_SYMBOL(dquot_commit); 471 472 /* 473 * Release dquot 474 */ 475 int dquot_release(struct dquot *dquot) 476 { 477 int ret = 0, ret2 = 0; 478 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 479 480 mutex_lock(&dquot->dq_lock); 481 /* Check whether we are not racing with some other dqget() */ 482 if (atomic_read(&dquot->dq_count) > 1) 483 goto out_dqlock; 484 mutex_lock(&dqopt->dqio_mutex); 485 if (dqopt->ops[dquot->dq_id.type]->release_dqblk) { 486 ret = dqopt->ops[dquot->dq_id.type]->release_dqblk(dquot); 487 /* Write the info */ 488 if (info_dirty(&dqopt->info[dquot->dq_id.type])) { 489 ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info( 490 dquot->dq_sb, dquot->dq_id.type); 491 } 492 if (ret >= 0) 493 ret = ret2; 494 } 495 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags); 496 mutex_unlock(&dqopt->dqio_mutex); 497 out_dqlock: 498 mutex_unlock(&dquot->dq_lock); 499 return ret; 500 } 501 EXPORT_SYMBOL(dquot_release); 502 503 void dquot_destroy(struct dquot *dquot) 504 { 505 kmem_cache_free(dquot_cachep, dquot); 506 } 507 EXPORT_SYMBOL(dquot_destroy); 508 509 static inline void do_destroy_dquot(struct dquot *dquot) 510 { 511 dquot->dq_sb->dq_op->destroy_dquot(dquot); 512 } 513 514 /* Invalidate all dquots on the list. Note that this function is called after 515 * quota is disabled and pointers from inodes removed so there cannot be new 516 * quota users. There can still be some users of quotas due to inodes being 517 * just deleted or pruned by prune_icache() (those are not attached to any 518 * list) or parallel quotactl call. We have to wait for such users. 519 */ 520 static void invalidate_dquots(struct super_block *sb, int type) 521 { 522 struct dquot *dquot, *tmp; 523 524 restart: 525 spin_lock(&dq_list_lock); 526 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) { 527 if (dquot->dq_sb != sb) 528 continue; 529 if (dquot->dq_id.type != type) 530 continue; 531 /* Wait for dquot users */ 532 if (atomic_read(&dquot->dq_count)) { 533 DEFINE_WAIT(wait); 534 535 dqgrab(dquot); 536 prepare_to_wait(&dquot->dq_wait_unused, &wait, 537 TASK_UNINTERRUPTIBLE); 538 spin_unlock(&dq_list_lock); 539 /* Once dqput() wakes us up, we know it's time to free 540 * the dquot. 541 * IMPORTANT: we rely on the fact that there is always 542 * at most one process waiting for dquot to free. 543 * Otherwise dq_count would be > 1 and we would never 544 * wake up. 545 */ 546 if (atomic_read(&dquot->dq_count) > 1) 547 schedule(); 548 finish_wait(&dquot->dq_wait_unused, &wait); 549 dqput(dquot); 550 /* At this moment dquot() need not exist (it could be 551 * reclaimed by prune_dqcache(). Hence we must 552 * restart. */ 553 goto restart; 554 } 555 /* 556 * Quota now has no users and it has been written on last 557 * dqput() 558 */ 559 remove_dquot_hash(dquot); 560 remove_free_dquot(dquot); 561 remove_inuse(dquot); 562 do_destroy_dquot(dquot); 563 } 564 spin_unlock(&dq_list_lock); 565 } 566 567 /* Call callback for every active dquot on given filesystem */ 568 int dquot_scan_active(struct super_block *sb, 569 int (*fn)(struct dquot *dquot, unsigned long priv), 570 unsigned long priv) 571 { 572 struct dquot *dquot, *old_dquot = NULL; 573 int ret = 0; 574 575 WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount)); 576 577 spin_lock(&dq_list_lock); 578 list_for_each_entry(dquot, &inuse_list, dq_inuse) { 579 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) 580 continue; 581 if (dquot->dq_sb != sb) 582 continue; 583 /* Now we have active dquot so we can just increase use count */ 584 atomic_inc(&dquot->dq_count); 585 spin_unlock(&dq_list_lock); 586 dqstats_inc(DQST_LOOKUPS); 587 dqput(old_dquot); 588 old_dquot = dquot; 589 /* 590 * ->release_dquot() can be racing with us. Our reference 591 * protects us from new calls to it so just wait for any 592 * outstanding call and recheck the DQ_ACTIVE_B after that. 593 */ 594 wait_on_dquot(dquot); 595 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 596 ret = fn(dquot, priv); 597 if (ret < 0) 598 goto out; 599 } 600 spin_lock(&dq_list_lock); 601 /* We are safe to continue now because our dquot could not 602 * be moved out of the inuse list while we hold the reference */ 603 } 604 spin_unlock(&dq_list_lock); 605 out: 606 dqput(old_dquot); 607 return ret; 608 } 609 EXPORT_SYMBOL(dquot_scan_active); 610 611 /* Write all dquot structures to quota files */ 612 int dquot_writeback_dquots(struct super_block *sb, int type) 613 { 614 struct list_head *dirty; 615 struct dquot *dquot; 616 struct quota_info *dqopt = sb_dqopt(sb); 617 int cnt; 618 int err, ret = 0; 619 620 WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount)); 621 622 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 623 if (type != -1 && cnt != type) 624 continue; 625 if (!sb_has_quota_active(sb, cnt)) 626 continue; 627 spin_lock(&dq_list_lock); 628 dirty = &dqopt->info[cnt].dqi_dirty_list; 629 while (!list_empty(dirty)) { 630 dquot = list_first_entry(dirty, struct dquot, 631 dq_dirty); 632 /* Dirty and inactive can be only bad dquot... */ 633 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 634 clear_dquot_dirty(dquot); 635 continue; 636 } 637 /* Now we have active dquot from which someone is 638 * holding reference so we can safely just increase 639 * use count */ 640 dqgrab(dquot); 641 spin_unlock(&dq_list_lock); 642 dqstats_inc(DQST_LOOKUPS); 643 err = sb->dq_op->write_dquot(dquot); 644 if (!ret && err) 645 ret = err; 646 dqput(dquot); 647 spin_lock(&dq_list_lock); 648 } 649 spin_unlock(&dq_list_lock); 650 } 651 652 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 653 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt) 654 && info_dirty(&dqopt->info[cnt])) 655 sb->dq_op->write_info(sb, cnt); 656 dqstats_inc(DQST_SYNCS); 657 658 return ret; 659 } 660 EXPORT_SYMBOL(dquot_writeback_dquots); 661 662 /* Write all dquot structures to disk and make them visible from userspace */ 663 int dquot_quota_sync(struct super_block *sb, int type) 664 { 665 struct quota_info *dqopt = sb_dqopt(sb); 666 int cnt; 667 int ret; 668 669 ret = dquot_writeback_dquots(sb, type); 670 if (ret) 671 return ret; 672 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 673 return 0; 674 675 /* This is not very clever (and fast) but currently I don't know about 676 * any other simple way of getting quota data to disk and we must get 677 * them there for userspace to be visible... */ 678 if (sb->s_op->sync_fs) 679 sb->s_op->sync_fs(sb, 1); 680 sync_blockdev(sb->s_bdev); 681 682 /* 683 * Now when everything is written we can discard the pagecache so 684 * that userspace sees the changes. 685 */ 686 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 687 if (type != -1 && cnt != type) 688 continue; 689 if (!sb_has_quota_active(sb, cnt)) 690 continue; 691 inode_lock(dqopt->files[cnt]); 692 truncate_inode_pages(&dqopt->files[cnt]->i_data, 0); 693 inode_unlock(dqopt->files[cnt]); 694 } 695 696 return 0; 697 } 698 EXPORT_SYMBOL(dquot_quota_sync); 699 700 static unsigned long 701 dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) 702 { 703 struct list_head *head; 704 struct dquot *dquot; 705 unsigned long freed = 0; 706 707 spin_lock(&dq_list_lock); 708 head = free_dquots.prev; 709 while (head != &free_dquots && sc->nr_to_scan) { 710 dquot = list_entry(head, struct dquot, dq_free); 711 remove_dquot_hash(dquot); 712 remove_free_dquot(dquot); 713 remove_inuse(dquot); 714 do_destroy_dquot(dquot); 715 sc->nr_to_scan--; 716 freed++; 717 head = free_dquots.prev; 718 } 719 spin_unlock(&dq_list_lock); 720 return freed; 721 } 722 723 static unsigned long 724 dqcache_shrink_count(struct shrinker *shrink, struct shrink_control *sc) 725 { 726 return vfs_pressure_ratio( 727 percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS])); 728 } 729 730 static struct shrinker dqcache_shrinker = { 731 .count_objects = dqcache_shrink_count, 732 .scan_objects = dqcache_shrink_scan, 733 .seeks = DEFAULT_SEEKS, 734 }; 735 736 /* 737 * Put reference to dquot 738 */ 739 void dqput(struct dquot *dquot) 740 { 741 int ret; 742 743 if (!dquot) 744 return; 745 #ifdef CONFIG_QUOTA_DEBUG 746 if (!atomic_read(&dquot->dq_count)) { 747 quota_error(dquot->dq_sb, "trying to free free dquot of %s %d", 748 quotatypes[dquot->dq_id.type], 749 from_kqid(&init_user_ns, dquot->dq_id)); 750 BUG(); 751 } 752 #endif 753 dqstats_inc(DQST_DROPS); 754 we_slept: 755 spin_lock(&dq_list_lock); 756 if (atomic_read(&dquot->dq_count) > 1) { 757 /* We have more than one user... nothing to do */ 758 atomic_dec(&dquot->dq_count); 759 /* Releasing dquot during quotaoff phase? */ 760 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_id.type) && 761 atomic_read(&dquot->dq_count) == 1) 762 wake_up(&dquot->dq_wait_unused); 763 spin_unlock(&dq_list_lock); 764 return; 765 } 766 /* Need to release dquot? */ 767 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { 768 spin_unlock(&dq_list_lock); 769 /* Commit dquot before releasing */ 770 ret = dquot->dq_sb->dq_op->write_dquot(dquot); 771 if (ret < 0) { 772 quota_error(dquot->dq_sb, "Can't write quota structure" 773 " (error %d). Quota may get out of sync!", 774 ret); 775 /* 776 * We clear dirty bit anyway, so that we avoid 777 * infinite loop here 778 */ 779 spin_lock(&dq_list_lock); 780 clear_dquot_dirty(dquot); 781 spin_unlock(&dq_list_lock); 782 } 783 goto we_slept; 784 } 785 /* Clear flag in case dquot was inactive (something bad happened) */ 786 clear_dquot_dirty(dquot); 787 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 788 spin_unlock(&dq_list_lock); 789 dquot->dq_sb->dq_op->release_dquot(dquot); 790 goto we_slept; 791 } 792 atomic_dec(&dquot->dq_count); 793 #ifdef CONFIG_QUOTA_DEBUG 794 /* sanity check */ 795 BUG_ON(!list_empty(&dquot->dq_free)); 796 #endif 797 put_dquot_last(dquot); 798 spin_unlock(&dq_list_lock); 799 } 800 EXPORT_SYMBOL(dqput); 801 802 struct dquot *dquot_alloc(struct super_block *sb, int type) 803 { 804 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); 805 } 806 EXPORT_SYMBOL(dquot_alloc); 807 808 static struct dquot *get_empty_dquot(struct super_block *sb, int type) 809 { 810 struct dquot *dquot; 811 812 dquot = sb->dq_op->alloc_dquot(sb, type); 813 if(!dquot) 814 return NULL; 815 816 mutex_init(&dquot->dq_lock); 817 INIT_LIST_HEAD(&dquot->dq_free); 818 INIT_LIST_HEAD(&dquot->dq_inuse); 819 INIT_HLIST_NODE(&dquot->dq_hash); 820 INIT_LIST_HEAD(&dquot->dq_dirty); 821 init_waitqueue_head(&dquot->dq_wait_unused); 822 dquot->dq_sb = sb; 823 dquot->dq_id = make_kqid_invalid(type); 824 atomic_set(&dquot->dq_count, 1); 825 826 return dquot; 827 } 828 829 /* 830 * Get reference to dquot 831 * 832 * Locking is slightly tricky here. We are guarded from parallel quotaoff() 833 * destroying our dquot by: 834 * a) checking for quota flags under dq_list_lock and 835 * b) getting a reference to dquot before we release dq_list_lock 836 */ 837 struct dquot *dqget(struct super_block *sb, struct kqid qid) 838 { 839 unsigned int hashent = hashfn(sb, qid); 840 struct dquot *dquot, *empty = NULL; 841 842 if (!qid_has_mapping(sb->s_user_ns, qid)) 843 return ERR_PTR(-EINVAL); 844 845 if (!sb_has_quota_active(sb, qid.type)) 846 return ERR_PTR(-ESRCH); 847 we_slept: 848 spin_lock(&dq_list_lock); 849 spin_lock(&dq_state_lock); 850 if (!sb_has_quota_active(sb, qid.type)) { 851 spin_unlock(&dq_state_lock); 852 spin_unlock(&dq_list_lock); 853 dquot = ERR_PTR(-ESRCH); 854 goto out; 855 } 856 spin_unlock(&dq_state_lock); 857 858 dquot = find_dquot(hashent, sb, qid); 859 if (!dquot) { 860 if (!empty) { 861 spin_unlock(&dq_list_lock); 862 empty = get_empty_dquot(sb, qid.type); 863 if (!empty) 864 schedule(); /* Try to wait for a moment... */ 865 goto we_slept; 866 } 867 dquot = empty; 868 empty = NULL; 869 dquot->dq_id = qid; 870 /* all dquots go on the inuse_list */ 871 put_inuse(dquot); 872 /* hash it first so it can be found */ 873 insert_dquot_hash(dquot); 874 spin_unlock(&dq_list_lock); 875 dqstats_inc(DQST_LOOKUPS); 876 } else { 877 if (!atomic_read(&dquot->dq_count)) 878 remove_free_dquot(dquot); 879 atomic_inc(&dquot->dq_count); 880 spin_unlock(&dq_list_lock); 881 dqstats_inc(DQST_CACHE_HITS); 882 dqstats_inc(DQST_LOOKUPS); 883 } 884 /* Wait for dq_lock - after this we know that either dquot_release() is 885 * already finished or it will be canceled due to dq_count > 1 test */ 886 wait_on_dquot(dquot); 887 /* Read the dquot / allocate space in quota file */ 888 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 889 int err; 890 891 err = sb->dq_op->acquire_dquot(dquot); 892 if (err < 0) { 893 dqput(dquot); 894 dquot = ERR_PTR(err); 895 goto out; 896 } 897 } 898 /* 899 * Make sure following reads see filled structure - paired with 900 * smp_mb__before_atomic() in dquot_acquire(). 901 */ 902 smp_rmb(); 903 #ifdef CONFIG_QUOTA_DEBUG 904 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ 905 #endif 906 out: 907 if (empty) 908 do_destroy_dquot(empty); 909 910 return dquot; 911 } 912 EXPORT_SYMBOL(dqget); 913 914 static inline struct dquot **i_dquot(struct inode *inode) 915 { 916 return inode->i_sb->s_op->get_dquots(inode); 917 } 918 919 static int dqinit_needed(struct inode *inode, int type) 920 { 921 struct dquot * const *dquots; 922 int cnt; 923 924 if (IS_NOQUOTA(inode)) 925 return 0; 926 927 dquots = i_dquot(inode); 928 if (type != -1) 929 return !dquots[type]; 930 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 931 if (!dquots[cnt]) 932 return 1; 933 return 0; 934 } 935 936 /* This routine is guarded by s_umount semaphore */ 937 static void add_dquot_ref(struct super_block *sb, int type) 938 { 939 struct inode *inode, *old_inode = NULL; 940 #ifdef CONFIG_QUOTA_DEBUG 941 int reserved = 0; 942 #endif 943 944 spin_lock(&sb->s_inode_list_lock); 945 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 946 spin_lock(&inode->i_lock); 947 if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || 948 !atomic_read(&inode->i_writecount) || 949 !dqinit_needed(inode, type)) { 950 spin_unlock(&inode->i_lock); 951 continue; 952 } 953 __iget(inode); 954 spin_unlock(&inode->i_lock); 955 spin_unlock(&sb->s_inode_list_lock); 956 957 #ifdef CONFIG_QUOTA_DEBUG 958 if (unlikely(inode_get_rsv_space(inode) > 0)) 959 reserved = 1; 960 #endif 961 iput(old_inode); 962 __dquot_initialize(inode, type); 963 964 /* 965 * We hold a reference to 'inode' so it couldn't have been 966 * removed from s_inodes list while we dropped the 967 * s_inode_list_lock. We cannot iput the inode now as we can be 968 * holding the last reference and we cannot iput it under 969 * s_inode_list_lock. So we keep the reference and iput it 970 * later. 971 */ 972 old_inode = inode; 973 spin_lock(&sb->s_inode_list_lock); 974 } 975 spin_unlock(&sb->s_inode_list_lock); 976 iput(old_inode); 977 978 #ifdef CONFIG_QUOTA_DEBUG 979 if (reserved) { 980 quota_error(sb, "Writes happened before quota was turned on " 981 "thus quota information is probably inconsistent. " 982 "Please run quotacheck(8)"); 983 } 984 #endif 985 } 986 987 /* 988 * Remove references to dquots from inode and add dquot to list for freeing 989 * if we have the last reference to dquot 990 */ 991 static void remove_inode_dquot_ref(struct inode *inode, int type, 992 struct list_head *tofree_head) 993 { 994 struct dquot **dquots = i_dquot(inode); 995 struct dquot *dquot = dquots[type]; 996 997 if (!dquot) 998 return; 999 1000 dquots[type] = NULL; 1001 if (list_empty(&dquot->dq_free)) { 1002 /* 1003 * The inode still has reference to dquot so it can't be in the 1004 * free list 1005 */ 1006 spin_lock(&dq_list_lock); 1007 list_add(&dquot->dq_free, tofree_head); 1008 spin_unlock(&dq_list_lock); 1009 } else { 1010 /* 1011 * Dquot is already in a list to put so we won't drop the last 1012 * reference here. 1013 */ 1014 dqput(dquot); 1015 } 1016 } 1017 1018 /* 1019 * Free list of dquots 1020 * Dquots are removed from inodes and no new references can be got so we are 1021 * the only ones holding reference 1022 */ 1023 static void put_dquot_list(struct list_head *tofree_head) 1024 { 1025 struct list_head *act_head; 1026 struct dquot *dquot; 1027 1028 act_head = tofree_head->next; 1029 while (act_head != tofree_head) { 1030 dquot = list_entry(act_head, struct dquot, dq_free); 1031 act_head = act_head->next; 1032 /* Remove dquot from the list so we won't have problems... */ 1033 list_del_init(&dquot->dq_free); 1034 dqput(dquot); 1035 } 1036 } 1037 1038 static void remove_dquot_ref(struct super_block *sb, int type, 1039 struct list_head *tofree_head) 1040 { 1041 struct inode *inode; 1042 int reserved = 0; 1043 1044 spin_lock(&sb->s_inode_list_lock); 1045 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 1046 /* 1047 * We have to scan also I_NEW inodes because they can already 1048 * have quota pointer initialized. Luckily, we need to touch 1049 * only quota pointers and these have separate locking 1050 * (dq_data_lock). 1051 */ 1052 spin_lock(&dq_data_lock); 1053 if (!IS_NOQUOTA(inode)) { 1054 if (unlikely(inode_get_rsv_space(inode) > 0)) 1055 reserved = 1; 1056 remove_inode_dquot_ref(inode, type, tofree_head); 1057 } 1058 spin_unlock(&dq_data_lock); 1059 } 1060 spin_unlock(&sb->s_inode_list_lock); 1061 #ifdef CONFIG_QUOTA_DEBUG 1062 if (reserved) { 1063 printk(KERN_WARNING "VFS (%s): Writes happened after quota" 1064 " was disabled thus quota information is probably " 1065 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 1066 } 1067 #endif 1068 } 1069 1070 /* Gather all references from inodes and drop them */ 1071 static void drop_dquot_ref(struct super_block *sb, int type) 1072 { 1073 LIST_HEAD(tofree_head); 1074 1075 if (sb->dq_op) { 1076 remove_dquot_ref(sb, type, &tofree_head); 1077 synchronize_srcu(&dquot_srcu); 1078 put_dquot_list(&tofree_head); 1079 } 1080 } 1081 1082 static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1083 { 1084 dquot->dq_dqb.dqb_curinodes += number; 1085 } 1086 1087 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1088 { 1089 dquot->dq_dqb.dqb_curspace += number; 1090 } 1091 1092 static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1093 { 1094 dquot->dq_dqb.dqb_rsvspace += number; 1095 } 1096 1097 /* 1098 * Claim reserved quota space 1099 */ 1100 static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1101 { 1102 if (dquot->dq_dqb.dqb_rsvspace < number) { 1103 WARN_ON_ONCE(1); 1104 number = dquot->dq_dqb.dqb_rsvspace; 1105 } 1106 dquot->dq_dqb.dqb_curspace += number; 1107 dquot->dq_dqb.dqb_rsvspace -= number; 1108 } 1109 1110 static void dquot_reclaim_reserved_space(struct dquot *dquot, qsize_t number) 1111 { 1112 if (WARN_ON_ONCE(dquot->dq_dqb.dqb_curspace < number)) 1113 number = dquot->dq_dqb.dqb_curspace; 1114 dquot->dq_dqb.dqb_rsvspace += number; 1115 dquot->dq_dqb.dqb_curspace -= number; 1116 } 1117 1118 static inline 1119 void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1120 { 1121 if (dquot->dq_dqb.dqb_rsvspace >= number) 1122 dquot->dq_dqb.dqb_rsvspace -= number; 1123 else { 1124 WARN_ON_ONCE(1); 1125 dquot->dq_dqb.dqb_rsvspace = 0; 1126 } 1127 } 1128 1129 static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1130 { 1131 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1132 dquot->dq_dqb.dqb_curinodes >= number) 1133 dquot->dq_dqb.dqb_curinodes -= number; 1134 else 1135 dquot->dq_dqb.dqb_curinodes = 0; 1136 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1137 dquot->dq_dqb.dqb_itime = (time64_t) 0; 1138 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1139 } 1140 1141 static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1142 { 1143 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1144 dquot->dq_dqb.dqb_curspace >= number) 1145 dquot->dq_dqb.dqb_curspace -= number; 1146 else 1147 dquot->dq_dqb.dqb_curspace = 0; 1148 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1149 dquot->dq_dqb.dqb_btime = (time64_t) 0; 1150 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1151 } 1152 1153 struct dquot_warn { 1154 struct super_block *w_sb; 1155 struct kqid w_dq_id; 1156 short w_type; 1157 }; 1158 1159 static int warning_issued(struct dquot *dquot, const int warntype) 1160 { 1161 int flag = (warntype == QUOTA_NL_BHARDWARN || 1162 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1163 ((warntype == QUOTA_NL_IHARDWARN || 1164 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1165 1166 if (!flag) 1167 return 0; 1168 return test_and_set_bit(flag, &dquot->dq_flags); 1169 } 1170 1171 #ifdef CONFIG_PRINT_QUOTA_WARNING 1172 static int flag_print_warnings = 1; 1173 1174 static int need_print_warning(struct dquot_warn *warn) 1175 { 1176 if (!flag_print_warnings) 1177 return 0; 1178 1179 switch (warn->w_dq_id.type) { 1180 case USRQUOTA: 1181 return uid_eq(current_fsuid(), warn->w_dq_id.uid); 1182 case GRPQUOTA: 1183 return in_group_p(warn->w_dq_id.gid); 1184 case PRJQUOTA: 1185 return 1; 1186 } 1187 return 0; 1188 } 1189 1190 /* Print warning to user which exceeded quota */ 1191 static void print_warning(struct dquot_warn *warn) 1192 { 1193 char *msg = NULL; 1194 struct tty_struct *tty; 1195 int warntype = warn->w_type; 1196 1197 if (warntype == QUOTA_NL_IHARDBELOW || 1198 warntype == QUOTA_NL_ISOFTBELOW || 1199 warntype == QUOTA_NL_BHARDBELOW || 1200 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(warn)) 1201 return; 1202 1203 tty = get_current_tty(); 1204 if (!tty) 1205 return; 1206 tty_write_message(tty, warn->w_sb->s_id); 1207 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1208 tty_write_message(tty, ": warning, "); 1209 else 1210 tty_write_message(tty, ": write failed, "); 1211 tty_write_message(tty, quotatypes[warn->w_dq_id.type]); 1212 switch (warntype) { 1213 case QUOTA_NL_IHARDWARN: 1214 msg = " file limit reached.\r\n"; 1215 break; 1216 case QUOTA_NL_ISOFTLONGWARN: 1217 msg = " file quota exceeded too long.\r\n"; 1218 break; 1219 case QUOTA_NL_ISOFTWARN: 1220 msg = " file quota exceeded.\r\n"; 1221 break; 1222 case QUOTA_NL_BHARDWARN: 1223 msg = " block limit reached.\r\n"; 1224 break; 1225 case QUOTA_NL_BSOFTLONGWARN: 1226 msg = " block quota exceeded too long.\r\n"; 1227 break; 1228 case QUOTA_NL_BSOFTWARN: 1229 msg = " block quota exceeded.\r\n"; 1230 break; 1231 } 1232 tty_write_message(tty, msg); 1233 tty_kref_put(tty); 1234 } 1235 #endif 1236 1237 static void prepare_warning(struct dquot_warn *warn, struct dquot *dquot, 1238 int warntype) 1239 { 1240 if (warning_issued(dquot, warntype)) 1241 return; 1242 warn->w_type = warntype; 1243 warn->w_sb = dquot->dq_sb; 1244 warn->w_dq_id = dquot->dq_id; 1245 } 1246 1247 /* 1248 * Write warnings to the console and send warning messages over netlink. 1249 * 1250 * Note that this function can call into tty and networking code. 1251 */ 1252 static void flush_warnings(struct dquot_warn *warn) 1253 { 1254 int i; 1255 1256 for (i = 0; i < MAXQUOTAS; i++) { 1257 if (warn[i].w_type == QUOTA_NL_NOWARN) 1258 continue; 1259 #ifdef CONFIG_PRINT_QUOTA_WARNING 1260 print_warning(&warn[i]); 1261 #endif 1262 quota_send_warning(warn[i].w_dq_id, 1263 warn[i].w_sb->s_dev, warn[i].w_type); 1264 } 1265 } 1266 1267 static int ignore_hardlimit(struct dquot *dquot) 1268 { 1269 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 1270 1271 return capable(CAP_SYS_RESOURCE) && 1272 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1273 !(info->dqi_flags & DQF_ROOT_SQUASH)); 1274 } 1275 1276 /* needs dq_data_lock */ 1277 static int check_idq(struct dquot *dquot, qsize_t inodes, 1278 struct dquot_warn *warn) 1279 { 1280 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1281 1282 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type) || 1283 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1284 return 0; 1285 1286 if (dquot->dq_dqb.dqb_ihardlimit && 1287 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1288 !ignore_hardlimit(dquot)) { 1289 prepare_warning(warn, dquot, QUOTA_NL_IHARDWARN); 1290 return -EDQUOT; 1291 } 1292 1293 if (dquot->dq_dqb.dqb_isoftlimit && 1294 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1295 dquot->dq_dqb.dqb_itime && 1296 ktime_get_real_seconds() >= dquot->dq_dqb.dqb_itime && 1297 !ignore_hardlimit(dquot)) { 1298 prepare_warning(warn, dquot, QUOTA_NL_ISOFTLONGWARN); 1299 return -EDQUOT; 1300 } 1301 1302 if (dquot->dq_dqb.dqb_isoftlimit && 1303 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1304 dquot->dq_dqb.dqb_itime == 0) { 1305 prepare_warning(warn, dquot, QUOTA_NL_ISOFTWARN); 1306 dquot->dq_dqb.dqb_itime = ktime_get_real_seconds() + 1307 sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type].dqi_igrace; 1308 } 1309 1310 return 0; 1311 } 1312 1313 /* needs dq_data_lock */ 1314 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, 1315 struct dquot_warn *warn) 1316 { 1317 qsize_t tspace; 1318 struct super_block *sb = dquot->dq_sb; 1319 1320 if (!sb_has_quota_limits_enabled(sb, dquot->dq_id.type) || 1321 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1322 return 0; 1323 1324 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1325 + space; 1326 1327 if (dquot->dq_dqb.dqb_bhardlimit && 1328 tspace > dquot->dq_dqb.dqb_bhardlimit && 1329 !ignore_hardlimit(dquot)) { 1330 if (!prealloc) 1331 prepare_warning(warn, dquot, QUOTA_NL_BHARDWARN); 1332 return -EDQUOT; 1333 } 1334 1335 if (dquot->dq_dqb.dqb_bsoftlimit && 1336 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1337 dquot->dq_dqb.dqb_btime && 1338 ktime_get_real_seconds() >= dquot->dq_dqb.dqb_btime && 1339 !ignore_hardlimit(dquot)) { 1340 if (!prealloc) 1341 prepare_warning(warn, dquot, QUOTA_NL_BSOFTLONGWARN); 1342 return -EDQUOT; 1343 } 1344 1345 if (dquot->dq_dqb.dqb_bsoftlimit && 1346 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1347 dquot->dq_dqb.dqb_btime == 0) { 1348 if (!prealloc) { 1349 prepare_warning(warn, dquot, QUOTA_NL_BSOFTWARN); 1350 dquot->dq_dqb.dqb_btime = ktime_get_real_seconds() + 1351 sb_dqopt(sb)->info[dquot->dq_id.type].dqi_bgrace; 1352 } 1353 else 1354 /* 1355 * We don't allow preallocation to exceed softlimit so exceeding will 1356 * be always printed 1357 */ 1358 return -EDQUOT; 1359 } 1360 1361 return 0; 1362 } 1363 1364 static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1365 { 1366 qsize_t newinodes; 1367 1368 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1369 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1370 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type)) 1371 return QUOTA_NL_NOWARN; 1372 1373 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1374 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1375 return QUOTA_NL_ISOFTBELOW; 1376 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1377 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1378 return QUOTA_NL_IHARDBELOW; 1379 return QUOTA_NL_NOWARN; 1380 } 1381 1382 static int info_bdq_free(struct dquot *dquot, qsize_t space) 1383 { 1384 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1385 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1386 return QUOTA_NL_NOWARN; 1387 1388 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1389 return QUOTA_NL_BSOFTBELOW; 1390 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1391 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1392 return QUOTA_NL_BHARDBELOW; 1393 return QUOTA_NL_NOWARN; 1394 } 1395 1396 static int dquot_active(const struct inode *inode) 1397 { 1398 struct super_block *sb = inode->i_sb; 1399 1400 if (IS_NOQUOTA(inode)) 1401 return 0; 1402 return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb); 1403 } 1404 1405 /* 1406 * Initialize quota pointers in inode 1407 * 1408 * It is better to call this function outside of any transaction as it 1409 * might need a lot of space in journal for dquot structure allocation. 1410 */ 1411 static int __dquot_initialize(struct inode *inode, int type) 1412 { 1413 int cnt, init_needed = 0; 1414 struct dquot **dquots, *got[MAXQUOTAS] = {}; 1415 struct super_block *sb = inode->i_sb; 1416 qsize_t rsv; 1417 int ret = 0; 1418 1419 if (!dquot_active(inode)) 1420 return 0; 1421 1422 dquots = i_dquot(inode); 1423 1424 /* First get references to structures we might need. */ 1425 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1426 struct kqid qid; 1427 kprojid_t projid; 1428 int rc; 1429 struct dquot *dquot; 1430 1431 if (type != -1 && cnt != type) 1432 continue; 1433 /* 1434 * The i_dquot should have been initialized in most cases, 1435 * we check it without locking here to avoid unnecessary 1436 * dqget()/dqput() calls. 1437 */ 1438 if (dquots[cnt]) 1439 continue; 1440 1441 if (!sb_has_quota_active(sb, cnt)) 1442 continue; 1443 1444 init_needed = 1; 1445 1446 switch (cnt) { 1447 case USRQUOTA: 1448 qid = make_kqid_uid(inode->i_uid); 1449 break; 1450 case GRPQUOTA: 1451 qid = make_kqid_gid(inode->i_gid); 1452 break; 1453 case PRJQUOTA: 1454 rc = inode->i_sb->dq_op->get_projid(inode, &projid); 1455 if (rc) 1456 continue; 1457 qid = make_kqid_projid(projid); 1458 break; 1459 } 1460 dquot = dqget(sb, qid); 1461 if (IS_ERR(dquot)) { 1462 /* We raced with somebody turning quotas off... */ 1463 if (PTR_ERR(dquot) != -ESRCH) { 1464 ret = PTR_ERR(dquot); 1465 goto out_put; 1466 } 1467 dquot = NULL; 1468 } 1469 got[cnt] = dquot; 1470 } 1471 1472 /* All required i_dquot has been initialized */ 1473 if (!init_needed) 1474 return 0; 1475 1476 spin_lock(&dq_data_lock); 1477 if (IS_NOQUOTA(inode)) 1478 goto out_lock; 1479 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1480 if (type != -1 && cnt != type) 1481 continue; 1482 /* Avoid races with quotaoff() */ 1483 if (!sb_has_quota_active(sb, cnt)) 1484 continue; 1485 /* We could race with quotaon or dqget() could have failed */ 1486 if (!got[cnt]) 1487 continue; 1488 if (!dquots[cnt]) { 1489 dquots[cnt] = got[cnt]; 1490 got[cnt] = NULL; 1491 /* 1492 * Make quota reservation system happy if someone 1493 * did a write before quota was turned on 1494 */ 1495 rsv = inode_get_rsv_space(inode); 1496 if (unlikely(rsv)) 1497 dquot_resv_space(dquots[cnt], rsv); 1498 } 1499 } 1500 out_lock: 1501 spin_unlock(&dq_data_lock); 1502 out_put: 1503 /* Drop unused references */ 1504 dqput_all(got); 1505 1506 return ret; 1507 } 1508 1509 int dquot_initialize(struct inode *inode) 1510 { 1511 return __dquot_initialize(inode, -1); 1512 } 1513 EXPORT_SYMBOL(dquot_initialize); 1514 1515 /* 1516 * Release all quotas referenced by inode. 1517 * 1518 * This function only be called on inode free or converting 1519 * a file to quota file, no other users for the i_dquot in 1520 * both cases, so we needn't call synchronize_srcu() after 1521 * clearing i_dquot. 1522 */ 1523 static void __dquot_drop(struct inode *inode) 1524 { 1525 int cnt; 1526 struct dquot **dquots = i_dquot(inode); 1527 struct dquot *put[MAXQUOTAS]; 1528 1529 spin_lock(&dq_data_lock); 1530 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1531 put[cnt] = dquots[cnt]; 1532 dquots[cnt] = NULL; 1533 } 1534 spin_unlock(&dq_data_lock); 1535 dqput_all(put); 1536 } 1537 1538 void dquot_drop(struct inode *inode) 1539 { 1540 struct dquot * const *dquots; 1541 int cnt; 1542 1543 if (IS_NOQUOTA(inode)) 1544 return; 1545 1546 /* 1547 * Test before calling to rule out calls from proc and such 1548 * where we are not allowed to block. Note that this is 1549 * actually reliable test even without the lock - the caller 1550 * must assure that nobody can come after the DQUOT_DROP and 1551 * add quota pointers back anyway. 1552 */ 1553 dquots = i_dquot(inode); 1554 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1555 if (dquots[cnt]) 1556 break; 1557 } 1558 1559 if (cnt < MAXQUOTAS) 1560 __dquot_drop(inode); 1561 } 1562 EXPORT_SYMBOL(dquot_drop); 1563 1564 /* 1565 * inode_reserved_space is managed internally by quota, and protected by 1566 * i_lock similar to i_blocks+i_bytes. 1567 */ 1568 static qsize_t *inode_reserved_space(struct inode * inode) 1569 { 1570 /* Filesystem must explicitly define it's own method in order to use 1571 * quota reservation interface */ 1572 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1573 return inode->i_sb->dq_op->get_reserved_space(inode); 1574 } 1575 1576 void inode_add_rsv_space(struct inode *inode, qsize_t number) 1577 { 1578 spin_lock(&inode->i_lock); 1579 *inode_reserved_space(inode) += number; 1580 spin_unlock(&inode->i_lock); 1581 } 1582 EXPORT_SYMBOL(inode_add_rsv_space); 1583 1584 void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1585 { 1586 spin_lock(&inode->i_lock); 1587 *inode_reserved_space(inode) -= number; 1588 __inode_add_bytes(inode, number); 1589 spin_unlock(&inode->i_lock); 1590 } 1591 EXPORT_SYMBOL(inode_claim_rsv_space); 1592 1593 void inode_reclaim_rsv_space(struct inode *inode, qsize_t number) 1594 { 1595 spin_lock(&inode->i_lock); 1596 *inode_reserved_space(inode) += number; 1597 __inode_sub_bytes(inode, number); 1598 spin_unlock(&inode->i_lock); 1599 } 1600 EXPORT_SYMBOL(inode_reclaim_rsv_space); 1601 1602 void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1603 { 1604 spin_lock(&inode->i_lock); 1605 *inode_reserved_space(inode) -= number; 1606 spin_unlock(&inode->i_lock); 1607 } 1608 EXPORT_SYMBOL(inode_sub_rsv_space); 1609 1610 static qsize_t inode_get_rsv_space(struct inode *inode) 1611 { 1612 qsize_t ret; 1613 1614 if (!inode->i_sb->dq_op->get_reserved_space) 1615 return 0; 1616 spin_lock(&inode->i_lock); 1617 ret = *inode_reserved_space(inode); 1618 spin_unlock(&inode->i_lock); 1619 return ret; 1620 } 1621 1622 static void inode_incr_space(struct inode *inode, qsize_t number, 1623 int reserve) 1624 { 1625 if (reserve) 1626 inode_add_rsv_space(inode, number); 1627 else 1628 inode_add_bytes(inode, number); 1629 } 1630 1631 static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1632 { 1633 if (reserve) 1634 inode_sub_rsv_space(inode, number); 1635 else 1636 inode_sub_bytes(inode, number); 1637 } 1638 1639 /* 1640 * This functions updates i_blocks+i_bytes fields and quota information 1641 * (together with appropriate checks). 1642 * 1643 * NOTE: We absolutely rely on the fact that caller dirties the inode 1644 * (usually helpers in quotaops.h care about this) and holds a handle for 1645 * the current transaction so that dquot write and inode write go into the 1646 * same transaction. 1647 */ 1648 1649 /* 1650 * This operation can block, but only after everything is updated 1651 */ 1652 int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags) 1653 { 1654 int cnt, ret = 0, index; 1655 struct dquot_warn warn[MAXQUOTAS]; 1656 int reserve = flags & DQUOT_SPACE_RESERVE; 1657 struct dquot **dquots; 1658 1659 if (!dquot_active(inode)) { 1660 inode_incr_space(inode, number, reserve); 1661 goto out; 1662 } 1663 1664 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1665 warn[cnt].w_type = QUOTA_NL_NOWARN; 1666 1667 dquots = i_dquot(inode); 1668 index = srcu_read_lock(&dquot_srcu); 1669 spin_lock(&dq_data_lock); 1670 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1671 if (!dquots[cnt]) 1672 continue; 1673 ret = check_bdq(dquots[cnt], number, 1674 !(flags & DQUOT_SPACE_WARN), &warn[cnt]); 1675 if (ret && !(flags & DQUOT_SPACE_NOFAIL)) { 1676 spin_unlock(&dq_data_lock); 1677 goto out_flush_warn; 1678 } 1679 } 1680 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1681 if (!dquots[cnt]) 1682 continue; 1683 if (reserve) 1684 dquot_resv_space(dquots[cnt], number); 1685 else 1686 dquot_incr_space(dquots[cnt], number); 1687 } 1688 inode_incr_space(inode, number, reserve); 1689 spin_unlock(&dq_data_lock); 1690 1691 if (reserve) 1692 goto out_flush_warn; 1693 mark_all_dquot_dirty(dquots); 1694 out_flush_warn: 1695 srcu_read_unlock(&dquot_srcu, index); 1696 flush_warnings(warn); 1697 out: 1698 return ret; 1699 } 1700 EXPORT_SYMBOL(__dquot_alloc_space); 1701 1702 /* 1703 * This operation can block, but only after everything is updated 1704 */ 1705 int dquot_alloc_inode(struct inode *inode) 1706 { 1707 int cnt, ret = 0, index; 1708 struct dquot_warn warn[MAXQUOTAS]; 1709 struct dquot * const *dquots; 1710 1711 if (!dquot_active(inode)) 1712 return 0; 1713 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1714 warn[cnt].w_type = QUOTA_NL_NOWARN; 1715 1716 dquots = i_dquot(inode); 1717 index = srcu_read_lock(&dquot_srcu); 1718 spin_lock(&dq_data_lock); 1719 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1720 if (!dquots[cnt]) 1721 continue; 1722 ret = check_idq(dquots[cnt], 1, &warn[cnt]); 1723 if (ret) 1724 goto warn_put_all; 1725 } 1726 1727 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1728 if (!dquots[cnt]) 1729 continue; 1730 dquot_incr_inodes(dquots[cnt], 1); 1731 } 1732 1733 warn_put_all: 1734 spin_unlock(&dq_data_lock); 1735 if (ret == 0) 1736 mark_all_dquot_dirty(dquots); 1737 srcu_read_unlock(&dquot_srcu, index); 1738 flush_warnings(warn); 1739 return ret; 1740 } 1741 EXPORT_SYMBOL(dquot_alloc_inode); 1742 1743 /* 1744 * Convert in-memory reserved quotas to real consumed quotas 1745 */ 1746 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1747 { 1748 struct dquot **dquots; 1749 int cnt, index; 1750 1751 if (!dquot_active(inode)) { 1752 inode_claim_rsv_space(inode, number); 1753 return 0; 1754 } 1755 1756 dquots = i_dquot(inode); 1757 index = srcu_read_lock(&dquot_srcu); 1758 spin_lock(&dq_data_lock); 1759 /* Claim reserved quotas to allocated quotas */ 1760 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1761 if (dquots[cnt]) 1762 dquot_claim_reserved_space(dquots[cnt], number); 1763 } 1764 /* Update inode bytes */ 1765 inode_claim_rsv_space(inode, number); 1766 spin_unlock(&dq_data_lock); 1767 mark_all_dquot_dirty(dquots); 1768 srcu_read_unlock(&dquot_srcu, index); 1769 return 0; 1770 } 1771 EXPORT_SYMBOL(dquot_claim_space_nodirty); 1772 1773 /* 1774 * Convert allocated space back to in-memory reserved quotas 1775 */ 1776 void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number) 1777 { 1778 struct dquot **dquots; 1779 int cnt, index; 1780 1781 if (!dquot_active(inode)) { 1782 inode_reclaim_rsv_space(inode, number); 1783 return; 1784 } 1785 1786 dquots = i_dquot(inode); 1787 index = srcu_read_lock(&dquot_srcu); 1788 spin_lock(&dq_data_lock); 1789 /* Claim reserved quotas to allocated quotas */ 1790 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1791 if (dquots[cnt]) 1792 dquot_reclaim_reserved_space(dquots[cnt], number); 1793 } 1794 /* Update inode bytes */ 1795 inode_reclaim_rsv_space(inode, number); 1796 spin_unlock(&dq_data_lock); 1797 mark_all_dquot_dirty(dquots); 1798 srcu_read_unlock(&dquot_srcu, index); 1799 return; 1800 } 1801 EXPORT_SYMBOL(dquot_reclaim_space_nodirty); 1802 1803 /* 1804 * This operation can block, but only after everything is updated 1805 */ 1806 void __dquot_free_space(struct inode *inode, qsize_t number, int flags) 1807 { 1808 unsigned int cnt; 1809 struct dquot_warn warn[MAXQUOTAS]; 1810 struct dquot **dquots; 1811 int reserve = flags & DQUOT_SPACE_RESERVE, index; 1812 1813 if (!dquot_active(inode)) { 1814 inode_decr_space(inode, number, reserve); 1815 return; 1816 } 1817 1818 dquots = i_dquot(inode); 1819 index = srcu_read_lock(&dquot_srcu); 1820 spin_lock(&dq_data_lock); 1821 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1822 int wtype; 1823 1824 warn[cnt].w_type = QUOTA_NL_NOWARN; 1825 if (!dquots[cnt]) 1826 continue; 1827 wtype = info_bdq_free(dquots[cnt], number); 1828 if (wtype != QUOTA_NL_NOWARN) 1829 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1830 if (reserve) 1831 dquot_free_reserved_space(dquots[cnt], number); 1832 else 1833 dquot_decr_space(dquots[cnt], number); 1834 } 1835 inode_decr_space(inode, number, reserve); 1836 spin_unlock(&dq_data_lock); 1837 1838 if (reserve) 1839 goto out_unlock; 1840 mark_all_dquot_dirty(dquots); 1841 out_unlock: 1842 srcu_read_unlock(&dquot_srcu, index); 1843 flush_warnings(warn); 1844 } 1845 EXPORT_SYMBOL(__dquot_free_space); 1846 1847 /* 1848 * This operation can block, but only after everything is updated 1849 */ 1850 void dquot_free_inode(struct inode *inode) 1851 { 1852 unsigned int cnt; 1853 struct dquot_warn warn[MAXQUOTAS]; 1854 struct dquot * const *dquots; 1855 int index; 1856 1857 if (!dquot_active(inode)) 1858 return; 1859 1860 dquots = i_dquot(inode); 1861 index = srcu_read_lock(&dquot_srcu); 1862 spin_lock(&dq_data_lock); 1863 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1864 int wtype; 1865 1866 warn[cnt].w_type = QUOTA_NL_NOWARN; 1867 if (!dquots[cnt]) 1868 continue; 1869 wtype = info_idq_free(dquots[cnt], 1); 1870 if (wtype != QUOTA_NL_NOWARN) 1871 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1872 dquot_decr_inodes(dquots[cnt], 1); 1873 } 1874 spin_unlock(&dq_data_lock); 1875 mark_all_dquot_dirty(dquots); 1876 srcu_read_unlock(&dquot_srcu, index); 1877 flush_warnings(warn); 1878 } 1879 EXPORT_SYMBOL(dquot_free_inode); 1880 1881 /* 1882 * Transfer the number of inode and blocks from one diskquota to an other. 1883 * On success, dquot references in transfer_to are consumed and references 1884 * to original dquots that need to be released are placed there. On failure, 1885 * references are kept untouched. 1886 * 1887 * This operation can block, but only after everything is updated 1888 * A transaction must be started when entering this function. 1889 * 1890 * We are holding reference on transfer_from & transfer_to, no need to 1891 * protect them by srcu_read_lock(). 1892 */ 1893 int __dquot_transfer(struct inode *inode, struct dquot **transfer_to) 1894 { 1895 qsize_t space, cur_space; 1896 qsize_t rsv_space = 0; 1897 struct dquot *transfer_from[MAXQUOTAS] = {}; 1898 int cnt, ret = 0; 1899 char is_valid[MAXQUOTAS] = {}; 1900 struct dquot_warn warn_to[MAXQUOTAS]; 1901 struct dquot_warn warn_from_inodes[MAXQUOTAS]; 1902 struct dquot_warn warn_from_space[MAXQUOTAS]; 1903 1904 if (IS_NOQUOTA(inode)) 1905 return 0; 1906 /* Initialize the arrays */ 1907 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1908 warn_to[cnt].w_type = QUOTA_NL_NOWARN; 1909 warn_from_inodes[cnt].w_type = QUOTA_NL_NOWARN; 1910 warn_from_space[cnt].w_type = QUOTA_NL_NOWARN; 1911 } 1912 1913 spin_lock(&dq_data_lock); 1914 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1915 spin_unlock(&dq_data_lock); 1916 return 0; 1917 } 1918 cur_space = inode_get_bytes(inode); 1919 rsv_space = inode_get_rsv_space(inode); 1920 space = cur_space + rsv_space; 1921 /* Build the transfer_from list and check the limits */ 1922 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1923 /* 1924 * Skip changes for same uid or gid or for turned off quota-type. 1925 */ 1926 if (!transfer_to[cnt]) 1927 continue; 1928 /* Avoid races with quotaoff() */ 1929 if (!sb_has_quota_active(inode->i_sb, cnt)) 1930 continue; 1931 is_valid[cnt] = 1; 1932 transfer_from[cnt] = i_dquot(inode)[cnt]; 1933 ret = check_idq(transfer_to[cnt], 1, &warn_to[cnt]); 1934 if (ret) 1935 goto over_quota; 1936 ret = check_bdq(transfer_to[cnt], space, 0, &warn_to[cnt]); 1937 if (ret) 1938 goto over_quota; 1939 } 1940 1941 /* 1942 * Finally perform the needed transfer from transfer_from to transfer_to 1943 */ 1944 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1945 if (!is_valid[cnt]) 1946 continue; 1947 /* Due to IO error we might not have transfer_from[] structure */ 1948 if (transfer_from[cnt]) { 1949 int wtype; 1950 wtype = info_idq_free(transfer_from[cnt], 1); 1951 if (wtype != QUOTA_NL_NOWARN) 1952 prepare_warning(&warn_from_inodes[cnt], 1953 transfer_from[cnt], wtype); 1954 wtype = info_bdq_free(transfer_from[cnt], space); 1955 if (wtype != QUOTA_NL_NOWARN) 1956 prepare_warning(&warn_from_space[cnt], 1957 transfer_from[cnt], wtype); 1958 dquot_decr_inodes(transfer_from[cnt], 1); 1959 dquot_decr_space(transfer_from[cnt], cur_space); 1960 dquot_free_reserved_space(transfer_from[cnt], 1961 rsv_space); 1962 } 1963 1964 dquot_incr_inodes(transfer_to[cnt], 1); 1965 dquot_incr_space(transfer_to[cnt], cur_space); 1966 dquot_resv_space(transfer_to[cnt], rsv_space); 1967 1968 i_dquot(inode)[cnt] = transfer_to[cnt]; 1969 } 1970 spin_unlock(&dq_data_lock); 1971 1972 mark_all_dquot_dirty(transfer_from); 1973 mark_all_dquot_dirty(transfer_to); 1974 flush_warnings(warn_to); 1975 flush_warnings(warn_from_inodes); 1976 flush_warnings(warn_from_space); 1977 /* Pass back references to put */ 1978 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1979 if (is_valid[cnt]) 1980 transfer_to[cnt] = transfer_from[cnt]; 1981 return 0; 1982 over_quota: 1983 spin_unlock(&dq_data_lock); 1984 flush_warnings(warn_to); 1985 return ret; 1986 } 1987 EXPORT_SYMBOL(__dquot_transfer); 1988 1989 /* Wrapper for transferring ownership of an inode for uid/gid only 1990 * Called from FSXXX_setattr() 1991 */ 1992 int dquot_transfer(struct inode *inode, struct iattr *iattr) 1993 { 1994 struct dquot *transfer_to[MAXQUOTAS] = {}; 1995 struct dquot *dquot; 1996 struct super_block *sb = inode->i_sb; 1997 int ret; 1998 1999 if (!dquot_active(inode)) 2000 return 0; 2001 2002 if (iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)){ 2003 dquot = dqget(sb, make_kqid_uid(iattr->ia_uid)); 2004 if (IS_ERR(dquot)) { 2005 if (PTR_ERR(dquot) != -ESRCH) { 2006 ret = PTR_ERR(dquot); 2007 goto out_put; 2008 } 2009 dquot = NULL; 2010 } 2011 transfer_to[USRQUOTA] = dquot; 2012 } 2013 if (iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid)){ 2014 dquot = dqget(sb, make_kqid_gid(iattr->ia_gid)); 2015 if (IS_ERR(dquot)) { 2016 if (PTR_ERR(dquot) != -ESRCH) { 2017 ret = PTR_ERR(dquot); 2018 goto out_put; 2019 } 2020 dquot = NULL; 2021 } 2022 transfer_to[GRPQUOTA] = dquot; 2023 } 2024 ret = __dquot_transfer(inode, transfer_to); 2025 out_put: 2026 dqput_all(transfer_to); 2027 return ret; 2028 } 2029 EXPORT_SYMBOL(dquot_transfer); 2030 2031 /* 2032 * Write info of quota file to disk 2033 */ 2034 int dquot_commit_info(struct super_block *sb, int type) 2035 { 2036 int ret; 2037 struct quota_info *dqopt = sb_dqopt(sb); 2038 2039 mutex_lock(&dqopt->dqio_mutex); 2040 ret = dqopt->ops[type]->write_file_info(sb, type); 2041 mutex_unlock(&dqopt->dqio_mutex); 2042 return ret; 2043 } 2044 EXPORT_SYMBOL(dquot_commit_info); 2045 2046 int dquot_get_next_id(struct super_block *sb, struct kqid *qid) 2047 { 2048 struct quota_info *dqopt = sb_dqopt(sb); 2049 int err; 2050 2051 if (!sb_has_quota_active(sb, qid->type)) 2052 return -ESRCH; 2053 if (!dqopt->ops[qid->type]->get_next_id) 2054 return -ENOSYS; 2055 mutex_lock(&dqopt->dqio_mutex); 2056 err = dqopt->ops[qid->type]->get_next_id(sb, qid); 2057 mutex_unlock(&dqopt->dqio_mutex); 2058 return err; 2059 } 2060 EXPORT_SYMBOL(dquot_get_next_id); 2061 2062 /* 2063 * Definitions of diskquota operations. 2064 */ 2065 const struct dquot_operations dquot_operations = { 2066 .write_dquot = dquot_commit, 2067 .acquire_dquot = dquot_acquire, 2068 .release_dquot = dquot_release, 2069 .mark_dirty = dquot_mark_dquot_dirty, 2070 .write_info = dquot_commit_info, 2071 .alloc_dquot = dquot_alloc, 2072 .destroy_dquot = dquot_destroy, 2073 .get_next_id = dquot_get_next_id, 2074 }; 2075 EXPORT_SYMBOL(dquot_operations); 2076 2077 /* 2078 * Generic helper for ->open on filesystems supporting disk quotas. 2079 */ 2080 int dquot_file_open(struct inode *inode, struct file *file) 2081 { 2082 int error; 2083 2084 error = generic_file_open(inode, file); 2085 if (!error && (file->f_mode & FMODE_WRITE)) 2086 dquot_initialize(inode); 2087 return error; 2088 } 2089 EXPORT_SYMBOL(dquot_file_open); 2090 2091 /* 2092 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 2093 */ 2094 int dquot_disable(struct super_block *sb, int type, unsigned int flags) 2095 { 2096 int cnt, ret = 0; 2097 struct quota_info *dqopt = sb_dqopt(sb); 2098 struct inode *toputinode[MAXQUOTAS]; 2099 2100 /* s_umount should be held in exclusive mode */ 2101 if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) 2102 up_read(&sb->s_umount); 2103 2104 /* Cannot turn off usage accounting without turning off limits, or 2105 * suspend quotas and simultaneously turn quotas off. */ 2106 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 2107 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 2108 DQUOT_USAGE_ENABLED))) 2109 return -EINVAL; 2110 2111 /* 2112 * Skip everything if there's nothing to do. We have to do this because 2113 * sometimes we are called when fill_super() failed and calling 2114 * sync_fs() in such cases does no good. 2115 */ 2116 if (!sb_any_quota_loaded(sb)) 2117 return 0; 2118 2119 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2120 toputinode[cnt] = NULL; 2121 if (type != -1 && cnt != type) 2122 continue; 2123 if (!sb_has_quota_loaded(sb, cnt)) 2124 continue; 2125 2126 if (flags & DQUOT_SUSPENDED) { 2127 spin_lock(&dq_state_lock); 2128 dqopt->flags |= 2129 dquot_state_flag(DQUOT_SUSPENDED, cnt); 2130 spin_unlock(&dq_state_lock); 2131 } else { 2132 spin_lock(&dq_state_lock); 2133 dqopt->flags &= ~dquot_state_flag(flags, cnt); 2134 /* Turning off suspended quotas? */ 2135 if (!sb_has_quota_loaded(sb, cnt) && 2136 sb_has_quota_suspended(sb, cnt)) { 2137 dqopt->flags &= ~dquot_state_flag( 2138 DQUOT_SUSPENDED, cnt); 2139 spin_unlock(&dq_state_lock); 2140 iput(dqopt->files[cnt]); 2141 dqopt->files[cnt] = NULL; 2142 continue; 2143 } 2144 spin_unlock(&dq_state_lock); 2145 } 2146 2147 /* We still have to keep quota loaded? */ 2148 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 2149 continue; 2150 2151 /* Note: these are blocking operations */ 2152 drop_dquot_ref(sb, cnt); 2153 invalidate_dquots(sb, cnt); 2154 /* 2155 * Now all dquots should be invalidated, all writes done so we 2156 * should be only users of the info. No locks needed. 2157 */ 2158 if (info_dirty(&dqopt->info[cnt])) 2159 sb->dq_op->write_info(sb, cnt); 2160 if (dqopt->ops[cnt]->free_file_info) 2161 dqopt->ops[cnt]->free_file_info(sb, cnt); 2162 put_quota_format(dqopt->info[cnt].dqi_format); 2163 2164 toputinode[cnt] = dqopt->files[cnt]; 2165 if (!sb_has_quota_loaded(sb, cnt)) 2166 dqopt->files[cnt] = NULL; 2167 dqopt->info[cnt].dqi_flags = 0; 2168 dqopt->info[cnt].dqi_igrace = 0; 2169 dqopt->info[cnt].dqi_bgrace = 0; 2170 dqopt->ops[cnt] = NULL; 2171 } 2172 2173 /* Skip syncing and setting flags if quota files are hidden */ 2174 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2175 goto put_inodes; 2176 2177 /* Sync the superblock so that buffers with quota data are written to 2178 * disk (and so userspace sees correct data afterwards). */ 2179 if (sb->s_op->sync_fs) 2180 sb->s_op->sync_fs(sb, 1); 2181 sync_blockdev(sb->s_bdev); 2182 /* Now the quota files are just ordinary files and we can set the 2183 * inode flags back. Moreover we discard the pagecache so that 2184 * userspace sees the writes we did bypassing the pagecache. We 2185 * must also discard the blockdev buffers so that we see the 2186 * changes done by userspace on the next quotaon() */ 2187 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2188 /* This can happen when suspending quotas on remount-ro... */ 2189 if (toputinode[cnt] && !sb_has_quota_loaded(sb, cnt)) { 2190 inode_lock(toputinode[cnt]); 2191 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 2192 S_NOATIME | S_NOQUOTA); 2193 truncate_inode_pages(&toputinode[cnt]->i_data, 0); 2194 inode_unlock(toputinode[cnt]); 2195 mark_inode_dirty_sync(toputinode[cnt]); 2196 } 2197 if (sb->s_bdev) 2198 invalidate_bdev(sb->s_bdev); 2199 put_inodes: 2200 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2201 if (toputinode[cnt]) { 2202 /* On remount RO, we keep the inode pointer so that we 2203 * can reenable quota on the subsequent remount RW. We 2204 * have to check 'flags' variable and not use sb_has_ 2205 * function because another quotaon / quotaoff could 2206 * change global state before we got here. We refuse 2207 * to suspend quotas when there is pending delete on 2208 * the quota file... */ 2209 if (!(flags & DQUOT_SUSPENDED)) 2210 iput(toputinode[cnt]); 2211 else if (!toputinode[cnt]->i_nlink) 2212 ret = -EBUSY; 2213 } 2214 return ret; 2215 } 2216 EXPORT_SYMBOL(dquot_disable); 2217 2218 int dquot_quota_off(struct super_block *sb, int type) 2219 { 2220 return dquot_disable(sb, type, 2221 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2222 } 2223 EXPORT_SYMBOL(dquot_quota_off); 2224 2225 /* 2226 * Turn quotas on on a device 2227 */ 2228 2229 /* 2230 * Helper function to turn quotas on when we already have the inode of 2231 * quota file and no quota information is loaded. 2232 */ 2233 static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 2234 unsigned int flags) 2235 { 2236 struct quota_format_type *fmt = find_quota_format(format_id); 2237 struct super_block *sb = inode->i_sb; 2238 struct quota_info *dqopt = sb_dqopt(sb); 2239 int error; 2240 int oldflags = -1; 2241 2242 if (!fmt) 2243 return -ESRCH; 2244 if (!S_ISREG(inode->i_mode)) { 2245 error = -EACCES; 2246 goto out_fmt; 2247 } 2248 if (IS_RDONLY(inode)) { 2249 error = -EROFS; 2250 goto out_fmt; 2251 } 2252 if (!sb->s_op->quota_write || !sb->s_op->quota_read || 2253 (type == PRJQUOTA && sb->dq_op->get_projid == NULL)) { 2254 error = -EINVAL; 2255 goto out_fmt; 2256 } 2257 /* Filesystems outside of init_user_ns not yet supported */ 2258 if (sb->s_user_ns != &init_user_ns) { 2259 error = -EINVAL; 2260 goto out_fmt; 2261 } 2262 /* Usage always has to be set... */ 2263 if (!(flags & DQUOT_USAGE_ENABLED)) { 2264 error = -EINVAL; 2265 goto out_fmt; 2266 } 2267 if (sb_has_quota_loaded(sb, type)) { 2268 error = -EBUSY; 2269 goto out_fmt; 2270 } 2271 2272 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2273 /* As we bypass the pagecache we must now flush all the 2274 * dirty data and invalidate caches so that kernel sees 2275 * changes from userspace. It is not enough to just flush 2276 * the quota file since if blocksize < pagesize, invalidation 2277 * of the cache could fail because of other unrelated dirty 2278 * data */ 2279 sync_filesystem(sb); 2280 invalidate_bdev(sb->s_bdev); 2281 } 2282 2283 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2284 /* We don't want quota and atime on quota files (deadlocks 2285 * possible) Also nobody should write to the file - we use 2286 * special IO operations which ignore the immutable bit. */ 2287 inode_lock(inode); 2288 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2289 S_NOQUOTA); 2290 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2291 inode_unlock(inode); 2292 /* 2293 * When S_NOQUOTA is set, remove dquot references as no more 2294 * references can be added 2295 */ 2296 __dquot_drop(inode); 2297 } 2298 2299 error = -EIO; 2300 dqopt->files[type] = igrab(inode); 2301 if (!dqopt->files[type]) 2302 goto out_file_flags; 2303 error = -EINVAL; 2304 if (!fmt->qf_ops->check_quota_file(sb, type)) 2305 goto out_file_init; 2306 2307 dqopt->ops[type] = fmt->qf_ops; 2308 dqopt->info[type].dqi_format = fmt; 2309 dqopt->info[type].dqi_fmt_id = format_id; 2310 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2311 mutex_lock(&dqopt->dqio_mutex); 2312 error = dqopt->ops[type]->read_file_info(sb, type); 2313 if (error < 0) { 2314 mutex_unlock(&dqopt->dqio_mutex); 2315 goto out_file_init; 2316 } 2317 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2318 dqopt->info[type].dqi_flags |= DQF_SYS_FILE; 2319 mutex_unlock(&dqopt->dqio_mutex); 2320 spin_lock(&dq_state_lock); 2321 dqopt->flags |= dquot_state_flag(flags, type); 2322 spin_unlock(&dq_state_lock); 2323 2324 add_dquot_ref(sb, type); 2325 2326 return 0; 2327 2328 out_file_init: 2329 dqopt->files[type] = NULL; 2330 iput(inode); 2331 out_file_flags: 2332 if (oldflags != -1) { 2333 inode_lock(inode); 2334 /* Set the flags back (in the case of accidental quotaon() 2335 * on a wrong file we don't want to mess up the flags) */ 2336 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2337 inode->i_flags |= oldflags; 2338 inode_unlock(inode); 2339 } 2340 out_fmt: 2341 put_quota_format(fmt); 2342 2343 return error; 2344 } 2345 2346 /* Reenable quotas on remount RW */ 2347 int dquot_resume(struct super_block *sb, int type) 2348 { 2349 struct quota_info *dqopt = sb_dqopt(sb); 2350 struct inode *inode; 2351 int ret = 0, cnt; 2352 unsigned int flags; 2353 2354 /* s_umount should be held in exclusive mode */ 2355 if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) 2356 up_read(&sb->s_umount); 2357 2358 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2359 if (type != -1 && cnt != type) 2360 continue; 2361 if (!sb_has_quota_suspended(sb, cnt)) 2362 continue; 2363 2364 inode = dqopt->files[cnt]; 2365 dqopt->files[cnt] = NULL; 2366 spin_lock(&dq_state_lock); 2367 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2368 DQUOT_LIMITS_ENABLED, 2369 cnt); 2370 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt); 2371 spin_unlock(&dq_state_lock); 2372 2373 flags = dquot_generic_flag(flags, cnt); 2374 ret = vfs_load_quota_inode(inode, cnt, 2375 dqopt->info[cnt].dqi_fmt_id, flags); 2376 iput(inode); 2377 } 2378 2379 return ret; 2380 } 2381 EXPORT_SYMBOL(dquot_resume); 2382 2383 int dquot_quota_on(struct super_block *sb, int type, int format_id, 2384 const struct path *path) 2385 { 2386 int error = security_quota_on(path->dentry); 2387 if (error) 2388 return error; 2389 /* Quota file not on the same filesystem? */ 2390 if (path->dentry->d_sb != sb) 2391 error = -EXDEV; 2392 else 2393 error = vfs_load_quota_inode(d_inode(path->dentry), type, 2394 format_id, DQUOT_USAGE_ENABLED | 2395 DQUOT_LIMITS_ENABLED); 2396 return error; 2397 } 2398 EXPORT_SYMBOL(dquot_quota_on); 2399 2400 /* 2401 * More powerful function for turning on quotas allowing setting 2402 * of individual quota flags 2403 */ 2404 int dquot_enable(struct inode *inode, int type, int format_id, 2405 unsigned int flags) 2406 { 2407 struct super_block *sb = inode->i_sb; 2408 2409 /* Just unsuspend quotas? */ 2410 BUG_ON(flags & DQUOT_SUSPENDED); 2411 /* s_umount should be held in exclusive mode */ 2412 if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) 2413 up_read(&sb->s_umount); 2414 2415 if (!flags) 2416 return 0; 2417 /* Just updating flags needed? */ 2418 if (sb_has_quota_loaded(sb, type)) { 2419 if (flags & DQUOT_USAGE_ENABLED && 2420 sb_has_quota_usage_enabled(sb, type)) 2421 return -EBUSY; 2422 if (flags & DQUOT_LIMITS_ENABLED && 2423 sb_has_quota_limits_enabled(sb, type)) 2424 return -EBUSY; 2425 spin_lock(&dq_state_lock); 2426 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2427 spin_unlock(&dq_state_lock); 2428 return 0; 2429 } 2430 2431 return vfs_load_quota_inode(inode, type, format_id, flags); 2432 } 2433 EXPORT_SYMBOL(dquot_enable); 2434 2435 /* 2436 * This function is used when filesystem needs to initialize quotas 2437 * during mount time. 2438 */ 2439 int dquot_quota_on_mount(struct super_block *sb, char *qf_name, 2440 int format_id, int type) 2441 { 2442 struct dentry *dentry; 2443 int error; 2444 2445 dentry = lookup_one_len_unlocked(qf_name, sb->s_root, strlen(qf_name)); 2446 if (IS_ERR(dentry)) 2447 return PTR_ERR(dentry); 2448 2449 if (d_really_is_negative(dentry)) { 2450 error = -ENOENT; 2451 goto out; 2452 } 2453 2454 error = security_quota_on(dentry); 2455 if (!error) 2456 error = vfs_load_quota_inode(d_inode(dentry), type, format_id, 2457 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2458 2459 out: 2460 dput(dentry); 2461 return error; 2462 } 2463 EXPORT_SYMBOL(dquot_quota_on_mount); 2464 2465 static int dquot_quota_enable(struct super_block *sb, unsigned int flags) 2466 { 2467 int ret; 2468 int type; 2469 struct quota_info *dqopt = sb_dqopt(sb); 2470 2471 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) 2472 return -ENOSYS; 2473 /* Accounting cannot be turned on while fs is mounted */ 2474 flags &= ~(FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT); 2475 if (!flags) 2476 return -EINVAL; 2477 for (type = 0; type < MAXQUOTAS; type++) { 2478 if (!(flags & qtype_enforce_flag(type))) 2479 continue; 2480 /* Can't enforce without accounting */ 2481 if (!sb_has_quota_usage_enabled(sb, type)) 2482 return -EINVAL; 2483 ret = dquot_enable(dqopt->files[type], type, 2484 dqopt->info[type].dqi_fmt_id, 2485 DQUOT_LIMITS_ENABLED); 2486 if (ret < 0) 2487 goto out_err; 2488 } 2489 return 0; 2490 out_err: 2491 /* Backout enforcement enablement we already did */ 2492 for (type--; type >= 0; type--) { 2493 if (flags & qtype_enforce_flag(type)) 2494 dquot_disable(sb, type, DQUOT_LIMITS_ENABLED); 2495 } 2496 /* Error code translation for better compatibility with XFS */ 2497 if (ret == -EBUSY) 2498 ret = -EEXIST; 2499 return ret; 2500 } 2501 2502 static int dquot_quota_disable(struct super_block *sb, unsigned int flags) 2503 { 2504 int ret; 2505 int type; 2506 struct quota_info *dqopt = sb_dqopt(sb); 2507 2508 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) 2509 return -ENOSYS; 2510 /* 2511 * We don't support turning off accounting via quotactl. In principle 2512 * quota infrastructure can do this but filesystems don't expect 2513 * userspace to be able to do it. 2514 */ 2515 if (flags & 2516 (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT)) 2517 return -EOPNOTSUPP; 2518 2519 /* Filter out limits not enabled */ 2520 for (type = 0; type < MAXQUOTAS; type++) 2521 if (!sb_has_quota_limits_enabled(sb, type)) 2522 flags &= ~qtype_enforce_flag(type); 2523 /* Nothing left? */ 2524 if (!flags) 2525 return -EEXIST; 2526 for (type = 0; type < MAXQUOTAS; type++) { 2527 if (flags & qtype_enforce_flag(type)) { 2528 ret = dquot_disable(sb, type, DQUOT_LIMITS_ENABLED); 2529 if (ret < 0) 2530 goto out_err; 2531 } 2532 } 2533 return 0; 2534 out_err: 2535 /* Backout enforcement disabling we already did */ 2536 for (type--; type >= 0; type--) { 2537 if (flags & qtype_enforce_flag(type)) 2538 dquot_enable(dqopt->files[type], type, 2539 dqopt->info[type].dqi_fmt_id, 2540 DQUOT_LIMITS_ENABLED); 2541 } 2542 return ret; 2543 } 2544 2545 /* Generic routine for getting common part of quota structure */ 2546 static void do_get_dqblk(struct dquot *dquot, struct qc_dqblk *di) 2547 { 2548 struct mem_dqblk *dm = &dquot->dq_dqb; 2549 2550 memset(di, 0, sizeof(*di)); 2551 spin_lock(&dq_data_lock); 2552 di->d_spc_hardlimit = dm->dqb_bhardlimit; 2553 di->d_spc_softlimit = dm->dqb_bsoftlimit; 2554 di->d_ino_hardlimit = dm->dqb_ihardlimit; 2555 di->d_ino_softlimit = dm->dqb_isoftlimit; 2556 di->d_space = dm->dqb_curspace + dm->dqb_rsvspace; 2557 di->d_ino_count = dm->dqb_curinodes; 2558 di->d_spc_timer = dm->dqb_btime; 2559 di->d_ino_timer = dm->dqb_itime; 2560 spin_unlock(&dq_data_lock); 2561 } 2562 2563 int dquot_get_dqblk(struct super_block *sb, struct kqid qid, 2564 struct qc_dqblk *di) 2565 { 2566 struct dquot *dquot; 2567 2568 dquot = dqget(sb, qid); 2569 if (IS_ERR(dquot)) 2570 return PTR_ERR(dquot); 2571 do_get_dqblk(dquot, di); 2572 dqput(dquot); 2573 2574 return 0; 2575 } 2576 EXPORT_SYMBOL(dquot_get_dqblk); 2577 2578 int dquot_get_next_dqblk(struct super_block *sb, struct kqid *qid, 2579 struct qc_dqblk *di) 2580 { 2581 struct dquot *dquot; 2582 int err; 2583 2584 if (!sb->dq_op->get_next_id) 2585 return -ENOSYS; 2586 err = sb->dq_op->get_next_id(sb, qid); 2587 if (err < 0) 2588 return err; 2589 dquot = dqget(sb, *qid); 2590 if (IS_ERR(dquot)) 2591 return PTR_ERR(dquot); 2592 do_get_dqblk(dquot, di); 2593 dqput(dquot); 2594 2595 return 0; 2596 } 2597 EXPORT_SYMBOL(dquot_get_next_dqblk); 2598 2599 #define VFS_QC_MASK \ 2600 (QC_SPACE | QC_SPC_SOFT | QC_SPC_HARD | \ 2601 QC_INO_COUNT | QC_INO_SOFT | QC_INO_HARD | \ 2602 QC_SPC_TIMER | QC_INO_TIMER) 2603 2604 /* Generic routine for setting common part of quota structure */ 2605 static int do_set_dqblk(struct dquot *dquot, struct qc_dqblk *di) 2606 { 2607 struct mem_dqblk *dm = &dquot->dq_dqb; 2608 int check_blim = 0, check_ilim = 0; 2609 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 2610 2611 if (di->d_fieldmask & ~VFS_QC_MASK) 2612 return -EINVAL; 2613 2614 if (((di->d_fieldmask & QC_SPC_SOFT) && 2615 di->d_spc_softlimit > dqi->dqi_max_spc_limit) || 2616 ((di->d_fieldmask & QC_SPC_HARD) && 2617 di->d_spc_hardlimit > dqi->dqi_max_spc_limit) || 2618 ((di->d_fieldmask & QC_INO_SOFT) && 2619 (di->d_ino_softlimit > dqi->dqi_max_ino_limit)) || 2620 ((di->d_fieldmask & QC_INO_HARD) && 2621 (di->d_ino_hardlimit > dqi->dqi_max_ino_limit))) 2622 return -ERANGE; 2623 2624 spin_lock(&dq_data_lock); 2625 if (di->d_fieldmask & QC_SPACE) { 2626 dm->dqb_curspace = di->d_space - dm->dqb_rsvspace; 2627 check_blim = 1; 2628 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2629 } 2630 2631 if (di->d_fieldmask & QC_SPC_SOFT) 2632 dm->dqb_bsoftlimit = di->d_spc_softlimit; 2633 if (di->d_fieldmask & QC_SPC_HARD) 2634 dm->dqb_bhardlimit = di->d_spc_hardlimit; 2635 if (di->d_fieldmask & (QC_SPC_SOFT | QC_SPC_HARD)) { 2636 check_blim = 1; 2637 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2638 } 2639 2640 if (di->d_fieldmask & QC_INO_COUNT) { 2641 dm->dqb_curinodes = di->d_ino_count; 2642 check_ilim = 1; 2643 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2644 } 2645 2646 if (di->d_fieldmask & QC_INO_SOFT) 2647 dm->dqb_isoftlimit = di->d_ino_softlimit; 2648 if (di->d_fieldmask & QC_INO_HARD) 2649 dm->dqb_ihardlimit = di->d_ino_hardlimit; 2650 if (di->d_fieldmask & (QC_INO_SOFT | QC_INO_HARD)) { 2651 check_ilim = 1; 2652 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2653 } 2654 2655 if (di->d_fieldmask & QC_SPC_TIMER) { 2656 dm->dqb_btime = di->d_spc_timer; 2657 check_blim = 1; 2658 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2659 } 2660 2661 if (di->d_fieldmask & QC_INO_TIMER) { 2662 dm->dqb_itime = di->d_ino_timer; 2663 check_ilim = 1; 2664 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2665 } 2666 2667 if (check_blim) { 2668 if (!dm->dqb_bsoftlimit || 2669 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2670 dm->dqb_btime = 0; 2671 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2672 } else if (!(di->d_fieldmask & QC_SPC_TIMER)) 2673 /* Set grace only if user hasn't provided his own... */ 2674 dm->dqb_btime = ktime_get_real_seconds() + dqi->dqi_bgrace; 2675 } 2676 if (check_ilim) { 2677 if (!dm->dqb_isoftlimit || 2678 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2679 dm->dqb_itime = 0; 2680 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2681 } else if (!(di->d_fieldmask & QC_INO_TIMER)) 2682 /* Set grace only if user hasn't provided his own... */ 2683 dm->dqb_itime = ktime_get_real_seconds() + dqi->dqi_igrace; 2684 } 2685 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2686 dm->dqb_isoftlimit) 2687 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2688 else 2689 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2690 spin_unlock(&dq_data_lock); 2691 mark_dquot_dirty(dquot); 2692 2693 return 0; 2694 } 2695 2696 int dquot_set_dqblk(struct super_block *sb, struct kqid qid, 2697 struct qc_dqblk *di) 2698 { 2699 struct dquot *dquot; 2700 int rc; 2701 2702 dquot = dqget(sb, qid); 2703 if (IS_ERR(dquot)) { 2704 rc = PTR_ERR(dquot); 2705 goto out; 2706 } 2707 rc = do_set_dqblk(dquot, di); 2708 dqput(dquot); 2709 out: 2710 return rc; 2711 } 2712 EXPORT_SYMBOL(dquot_set_dqblk); 2713 2714 /* Generic routine for getting common part of quota file information */ 2715 int dquot_get_state(struct super_block *sb, struct qc_state *state) 2716 { 2717 struct mem_dqinfo *mi; 2718 struct qc_type_state *tstate; 2719 struct quota_info *dqopt = sb_dqopt(sb); 2720 int type; 2721 2722 memset(state, 0, sizeof(*state)); 2723 for (type = 0; type < MAXQUOTAS; type++) { 2724 if (!sb_has_quota_active(sb, type)) 2725 continue; 2726 tstate = state->s_state + type; 2727 mi = sb_dqopt(sb)->info + type; 2728 tstate->flags = QCI_ACCT_ENABLED; 2729 spin_lock(&dq_data_lock); 2730 if (mi->dqi_flags & DQF_SYS_FILE) 2731 tstate->flags |= QCI_SYSFILE; 2732 if (mi->dqi_flags & DQF_ROOT_SQUASH) 2733 tstate->flags |= QCI_ROOT_SQUASH; 2734 if (sb_has_quota_limits_enabled(sb, type)) 2735 tstate->flags |= QCI_LIMITS_ENFORCED; 2736 tstate->spc_timelimit = mi->dqi_bgrace; 2737 tstate->ino_timelimit = mi->dqi_igrace; 2738 tstate->ino = dqopt->files[type]->i_ino; 2739 tstate->blocks = dqopt->files[type]->i_blocks; 2740 tstate->nextents = 1; /* We don't know... */ 2741 spin_unlock(&dq_data_lock); 2742 } 2743 return 0; 2744 } 2745 EXPORT_SYMBOL(dquot_get_state); 2746 2747 /* Generic routine for setting common part of quota file information */ 2748 int dquot_set_dqinfo(struct super_block *sb, int type, struct qc_info *ii) 2749 { 2750 struct mem_dqinfo *mi; 2751 int err = 0; 2752 2753 if ((ii->i_fieldmask & QC_WARNS_MASK) || 2754 (ii->i_fieldmask & QC_RT_SPC_TIMER)) 2755 return -EINVAL; 2756 if (!sb_has_quota_active(sb, type)) 2757 return -ESRCH; 2758 mi = sb_dqopt(sb)->info + type; 2759 if (ii->i_fieldmask & QC_FLAGS) { 2760 if ((ii->i_flags & QCI_ROOT_SQUASH && 2761 mi->dqi_format->qf_fmt_id != QFMT_VFS_OLD)) 2762 return -EINVAL; 2763 } 2764 spin_lock(&dq_data_lock); 2765 if (ii->i_fieldmask & QC_SPC_TIMER) 2766 mi->dqi_bgrace = ii->i_spc_timelimit; 2767 if (ii->i_fieldmask & QC_INO_TIMER) 2768 mi->dqi_igrace = ii->i_ino_timelimit; 2769 if (ii->i_fieldmask & QC_FLAGS) { 2770 if (ii->i_flags & QCI_ROOT_SQUASH) 2771 mi->dqi_flags |= DQF_ROOT_SQUASH; 2772 else 2773 mi->dqi_flags &= ~DQF_ROOT_SQUASH; 2774 } 2775 spin_unlock(&dq_data_lock); 2776 mark_info_dirty(sb, type); 2777 /* Force write to disk */ 2778 sb->dq_op->write_info(sb, type); 2779 return err; 2780 } 2781 EXPORT_SYMBOL(dquot_set_dqinfo); 2782 2783 const struct quotactl_ops dquot_quotactl_ops = { 2784 .quota_on = dquot_quota_on, 2785 .quota_off = dquot_quota_off, 2786 .quota_sync = dquot_quota_sync, 2787 .get_state = dquot_get_state, 2788 .set_info = dquot_set_dqinfo, 2789 .get_dqblk = dquot_get_dqblk, 2790 .get_nextdqblk = dquot_get_next_dqblk, 2791 .set_dqblk = dquot_set_dqblk 2792 }; 2793 EXPORT_SYMBOL(dquot_quotactl_ops); 2794 2795 const struct quotactl_ops dquot_quotactl_sysfile_ops = { 2796 .quota_enable = dquot_quota_enable, 2797 .quota_disable = dquot_quota_disable, 2798 .quota_sync = dquot_quota_sync, 2799 .get_state = dquot_get_state, 2800 .set_info = dquot_set_dqinfo, 2801 .get_dqblk = dquot_get_dqblk, 2802 .get_nextdqblk = dquot_get_next_dqblk, 2803 .set_dqblk = dquot_set_dqblk 2804 }; 2805 EXPORT_SYMBOL(dquot_quotactl_sysfile_ops); 2806 2807 static int do_proc_dqstats(struct ctl_table *table, int write, 2808 void __user *buffer, size_t *lenp, loff_t *ppos) 2809 { 2810 unsigned int type = (int *)table->data - dqstats.stat; 2811 2812 /* Update global table */ 2813 dqstats.stat[type] = 2814 percpu_counter_sum_positive(&dqstats.counter[type]); 2815 return proc_dointvec(table, write, buffer, lenp, ppos); 2816 } 2817 2818 static struct ctl_table fs_dqstats_table[] = { 2819 { 2820 .procname = "lookups", 2821 .data = &dqstats.stat[DQST_LOOKUPS], 2822 .maxlen = sizeof(int), 2823 .mode = 0444, 2824 .proc_handler = do_proc_dqstats, 2825 }, 2826 { 2827 .procname = "drops", 2828 .data = &dqstats.stat[DQST_DROPS], 2829 .maxlen = sizeof(int), 2830 .mode = 0444, 2831 .proc_handler = do_proc_dqstats, 2832 }, 2833 { 2834 .procname = "reads", 2835 .data = &dqstats.stat[DQST_READS], 2836 .maxlen = sizeof(int), 2837 .mode = 0444, 2838 .proc_handler = do_proc_dqstats, 2839 }, 2840 { 2841 .procname = "writes", 2842 .data = &dqstats.stat[DQST_WRITES], 2843 .maxlen = sizeof(int), 2844 .mode = 0444, 2845 .proc_handler = do_proc_dqstats, 2846 }, 2847 { 2848 .procname = "cache_hits", 2849 .data = &dqstats.stat[DQST_CACHE_HITS], 2850 .maxlen = sizeof(int), 2851 .mode = 0444, 2852 .proc_handler = do_proc_dqstats, 2853 }, 2854 { 2855 .procname = "allocated_dquots", 2856 .data = &dqstats.stat[DQST_ALLOC_DQUOTS], 2857 .maxlen = sizeof(int), 2858 .mode = 0444, 2859 .proc_handler = do_proc_dqstats, 2860 }, 2861 { 2862 .procname = "free_dquots", 2863 .data = &dqstats.stat[DQST_FREE_DQUOTS], 2864 .maxlen = sizeof(int), 2865 .mode = 0444, 2866 .proc_handler = do_proc_dqstats, 2867 }, 2868 { 2869 .procname = "syncs", 2870 .data = &dqstats.stat[DQST_SYNCS], 2871 .maxlen = sizeof(int), 2872 .mode = 0444, 2873 .proc_handler = do_proc_dqstats, 2874 }, 2875 #ifdef CONFIG_PRINT_QUOTA_WARNING 2876 { 2877 .procname = "warnings", 2878 .data = &flag_print_warnings, 2879 .maxlen = sizeof(int), 2880 .mode = 0644, 2881 .proc_handler = proc_dointvec, 2882 }, 2883 #endif 2884 { }, 2885 }; 2886 2887 static struct ctl_table fs_table[] = { 2888 { 2889 .procname = "quota", 2890 .mode = 0555, 2891 .child = fs_dqstats_table, 2892 }, 2893 { }, 2894 }; 2895 2896 static struct ctl_table sys_table[] = { 2897 { 2898 .procname = "fs", 2899 .mode = 0555, 2900 .child = fs_table, 2901 }, 2902 { }, 2903 }; 2904 2905 static int __init dquot_init(void) 2906 { 2907 int i, ret; 2908 unsigned long nr_hash, order; 2909 2910 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2911 2912 register_sysctl_table(sys_table); 2913 2914 dquot_cachep = kmem_cache_create("dquot", 2915 sizeof(struct dquot), sizeof(unsigned long) * 4, 2916 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2917 SLAB_MEM_SPREAD|SLAB_PANIC), 2918 NULL); 2919 2920 order = 0; 2921 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2922 if (!dquot_hash) 2923 panic("Cannot create dquot hash table"); 2924 2925 for (i = 0; i < _DQST_DQSTAT_LAST; i++) { 2926 ret = percpu_counter_init(&dqstats.counter[i], 0, GFP_KERNEL); 2927 if (ret) 2928 panic("Cannot create dquot stat counters"); 2929 } 2930 2931 /* Find power-of-two hlist_heads which can fit into allocation */ 2932 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2933 dq_hash_bits = 0; 2934 do { 2935 dq_hash_bits++; 2936 } while (nr_hash >> dq_hash_bits); 2937 dq_hash_bits--; 2938 2939 nr_hash = 1UL << dq_hash_bits; 2940 dq_hash_mask = nr_hash - 1; 2941 for (i = 0; i < nr_hash; i++) 2942 INIT_HLIST_HEAD(dquot_hash + i); 2943 2944 pr_info("VFS: Dquot-cache hash table entries: %ld (order %ld," 2945 " %ld bytes)\n", nr_hash, order, (PAGE_SIZE << order)); 2946 2947 register_shrinker(&dqcache_shrinker); 2948 2949 return 0; 2950 } 2951 fs_initcall(dquot_init); 2952