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