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 * dqonoff_mutex > i_mutex > journal_lock > dquot->dq_lock > dqio_mutex 123 * dqonoff_mutex > i_mutex comes from dquot_quota_sync, dquot_enable, etc. 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 set_bit(DQ_READ_B, &dquot->dq_flags); 415 /* Instantiate dquot if needed */ 416 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) { 417 ret = dqopt->ops[dquot->dq_id.type]->commit_dqblk(dquot); 418 /* Write the info if needed */ 419 if (info_dirty(&dqopt->info[dquot->dq_id.type])) { 420 ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info( 421 dquot->dq_sb, dquot->dq_id.type); 422 } 423 if (ret < 0) 424 goto out_iolock; 425 if (ret2 < 0) { 426 ret = ret2; 427 goto out_iolock; 428 } 429 } 430 set_bit(DQ_ACTIVE_B, &dquot->dq_flags); 431 out_iolock: 432 mutex_unlock(&dqopt->dqio_mutex); 433 mutex_unlock(&dquot->dq_lock); 434 return ret; 435 } 436 EXPORT_SYMBOL(dquot_acquire); 437 438 /* 439 * Write dquot to disk 440 */ 441 int dquot_commit(struct dquot *dquot) 442 { 443 int ret = 0; 444 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 445 446 mutex_lock(&dqopt->dqio_mutex); 447 spin_lock(&dq_list_lock); 448 if (!clear_dquot_dirty(dquot)) { 449 spin_unlock(&dq_list_lock); 450 goto out_sem; 451 } 452 spin_unlock(&dq_list_lock); 453 /* Inactive dquot can be only if there was error during read/init 454 * => we have better not writing it */ 455 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) 456 ret = dqopt->ops[dquot->dq_id.type]->commit_dqblk(dquot); 457 else 458 ret = -EIO; 459 out_sem: 460 mutex_unlock(&dqopt->dqio_mutex); 461 return ret; 462 } 463 EXPORT_SYMBOL(dquot_commit); 464 465 /* 466 * Release dquot 467 */ 468 int dquot_release(struct dquot *dquot) 469 { 470 int ret = 0, ret2 = 0; 471 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 472 473 mutex_lock(&dquot->dq_lock); 474 /* Check whether we are not racing with some other dqget() */ 475 if (atomic_read(&dquot->dq_count) > 1) 476 goto out_dqlock; 477 mutex_lock(&dqopt->dqio_mutex); 478 if (dqopt->ops[dquot->dq_id.type]->release_dqblk) { 479 ret = dqopt->ops[dquot->dq_id.type]->release_dqblk(dquot); 480 /* Write the info */ 481 if (info_dirty(&dqopt->info[dquot->dq_id.type])) { 482 ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info( 483 dquot->dq_sb, dquot->dq_id.type); 484 } 485 if (ret >= 0) 486 ret = ret2; 487 } 488 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags); 489 mutex_unlock(&dqopt->dqio_mutex); 490 out_dqlock: 491 mutex_unlock(&dquot->dq_lock); 492 return ret; 493 } 494 EXPORT_SYMBOL(dquot_release); 495 496 void dquot_destroy(struct dquot *dquot) 497 { 498 kmem_cache_free(dquot_cachep, dquot); 499 } 500 EXPORT_SYMBOL(dquot_destroy); 501 502 static inline void do_destroy_dquot(struct dquot *dquot) 503 { 504 dquot->dq_sb->dq_op->destroy_dquot(dquot); 505 } 506 507 /* Invalidate all dquots on the list. Note that this function is called after 508 * quota is disabled and pointers from inodes removed so there cannot be new 509 * quota users. There can still be some users of quotas due to inodes being 510 * just deleted or pruned by prune_icache() (those are not attached to any 511 * list) or parallel quotactl call. We have to wait for such users. 512 */ 513 static void invalidate_dquots(struct super_block *sb, int type) 514 { 515 struct dquot *dquot, *tmp; 516 517 restart: 518 spin_lock(&dq_list_lock); 519 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) { 520 if (dquot->dq_sb != sb) 521 continue; 522 if (dquot->dq_id.type != type) 523 continue; 524 /* Wait for dquot users */ 525 if (atomic_read(&dquot->dq_count)) { 526 DEFINE_WAIT(wait); 527 528 dqgrab(dquot); 529 prepare_to_wait(&dquot->dq_wait_unused, &wait, 530 TASK_UNINTERRUPTIBLE); 531 spin_unlock(&dq_list_lock); 532 /* Once dqput() wakes us up, we know it's time to free 533 * the dquot. 534 * IMPORTANT: we rely on the fact that there is always 535 * at most one process waiting for dquot to free. 536 * Otherwise dq_count would be > 1 and we would never 537 * wake up. 538 */ 539 if (atomic_read(&dquot->dq_count) > 1) 540 schedule(); 541 finish_wait(&dquot->dq_wait_unused, &wait); 542 dqput(dquot); 543 /* At this moment dquot() need not exist (it could be 544 * reclaimed by prune_dqcache(). Hence we must 545 * restart. */ 546 goto restart; 547 } 548 /* 549 * Quota now has no users and it has been written on last 550 * dqput() 551 */ 552 remove_dquot_hash(dquot); 553 remove_free_dquot(dquot); 554 remove_inuse(dquot); 555 do_destroy_dquot(dquot); 556 } 557 spin_unlock(&dq_list_lock); 558 } 559 560 /* Call callback for every active dquot on given filesystem */ 561 int dquot_scan_active(struct super_block *sb, 562 int (*fn)(struct dquot *dquot, unsigned long priv), 563 unsigned long priv) 564 { 565 struct dquot *dquot, *old_dquot = NULL; 566 int ret = 0; 567 568 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 569 spin_lock(&dq_list_lock); 570 list_for_each_entry(dquot, &inuse_list, dq_inuse) { 571 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) 572 continue; 573 if (dquot->dq_sb != sb) 574 continue; 575 /* Now we have active dquot so we can just increase use count */ 576 atomic_inc(&dquot->dq_count); 577 spin_unlock(&dq_list_lock); 578 dqstats_inc(DQST_LOOKUPS); 579 dqput(old_dquot); 580 old_dquot = dquot; 581 /* 582 * ->release_dquot() can be racing with us. Our reference 583 * protects us from new calls to it so just wait for any 584 * outstanding call and recheck the DQ_ACTIVE_B after that. 585 */ 586 wait_on_dquot(dquot); 587 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 588 ret = fn(dquot, priv); 589 if (ret < 0) 590 goto out; 591 } 592 spin_lock(&dq_list_lock); 593 /* We are safe to continue now because our dquot could not 594 * be moved out of the inuse list while we hold the reference */ 595 } 596 spin_unlock(&dq_list_lock); 597 out: 598 dqput(old_dquot); 599 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 600 return ret; 601 } 602 EXPORT_SYMBOL(dquot_scan_active); 603 604 /* Write all dquot structures to quota files */ 605 int dquot_writeback_dquots(struct super_block *sb, int type) 606 { 607 struct list_head *dirty; 608 struct dquot *dquot; 609 struct quota_info *dqopt = sb_dqopt(sb); 610 int cnt; 611 int err, ret = 0; 612 613 mutex_lock(&dqopt->dqonoff_mutex); 614 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 615 if (type != -1 && cnt != type) 616 continue; 617 if (!sb_has_quota_active(sb, cnt)) 618 continue; 619 spin_lock(&dq_list_lock); 620 dirty = &dqopt->info[cnt].dqi_dirty_list; 621 while (!list_empty(dirty)) { 622 dquot = list_first_entry(dirty, struct dquot, 623 dq_dirty); 624 /* Dirty and inactive can be only bad dquot... */ 625 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 626 clear_dquot_dirty(dquot); 627 continue; 628 } 629 /* Now we have active dquot from which someone is 630 * holding reference so we can safely just increase 631 * use count */ 632 dqgrab(dquot); 633 spin_unlock(&dq_list_lock); 634 dqstats_inc(DQST_LOOKUPS); 635 err = sb->dq_op->write_dquot(dquot); 636 if (!ret && err) 637 ret = err; 638 dqput(dquot); 639 spin_lock(&dq_list_lock); 640 } 641 spin_unlock(&dq_list_lock); 642 } 643 644 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 645 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt) 646 && info_dirty(&dqopt->info[cnt])) 647 sb->dq_op->write_info(sb, cnt); 648 dqstats_inc(DQST_SYNCS); 649 mutex_unlock(&dqopt->dqonoff_mutex); 650 651 return ret; 652 } 653 EXPORT_SYMBOL(dquot_writeback_dquots); 654 655 /* Write all dquot structures to disk and make them visible from userspace */ 656 int dquot_quota_sync(struct super_block *sb, int type) 657 { 658 struct quota_info *dqopt = sb_dqopt(sb); 659 int cnt; 660 int ret; 661 662 ret = dquot_writeback_dquots(sb, type); 663 if (ret) 664 return ret; 665 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 666 return 0; 667 668 /* This is not very clever (and fast) but currently I don't know about 669 * any other simple way of getting quota data to disk and we must get 670 * them there for userspace to be visible... */ 671 if (sb->s_op->sync_fs) 672 sb->s_op->sync_fs(sb, 1); 673 sync_blockdev(sb->s_bdev); 674 675 /* 676 * Now when everything is written we can discard the pagecache so 677 * that userspace sees the changes. 678 */ 679 mutex_lock(&dqopt->dqonoff_mutex); 680 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 681 if (type != -1 && cnt != type) 682 continue; 683 if (!sb_has_quota_active(sb, cnt)) 684 continue; 685 inode_lock(dqopt->files[cnt]); 686 truncate_inode_pages(&dqopt->files[cnt]->i_data, 0); 687 inode_unlock(dqopt->files[cnt]); 688 } 689 mutex_unlock(&dqopt->dqonoff_mutex); 690 691 return 0; 692 } 693 EXPORT_SYMBOL(dquot_quota_sync); 694 695 static unsigned long 696 dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) 697 { 698 struct list_head *head; 699 struct dquot *dquot; 700 unsigned long freed = 0; 701 702 spin_lock(&dq_list_lock); 703 head = free_dquots.prev; 704 while (head != &free_dquots && sc->nr_to_scan) { 705 dquot = list_entry(head, struct dquot, dq_free); 706 remove_dquot_hash(dquot); 707 remove_free_dquot(dquot); 708 remove_inuse(dquot); 709 do_destroy_dquot(dquot); 710 sc->nr_to_scan--; 711 freed++; 712 head = free_dquots.prev; 713 } 714 spin_unlock(&dq_list_lock); 715 return freed; 716 } 717 718 static unsigned long 719 dqcache_shrink_count(struct shrinker *shrink, struct shrink_control *sc) 720 { 721 return vfs_pressure_ratio( 722 percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS])); 723 } 724 725 static struct shrinker dqcache_shrinker = { 726 .count_objects = dqcache_shrink_count, 727 .scan_objects = dqcache_shrink_scan, 728 .seeks = DEFAULT_SEEKS, 729 }; 730 731 /* 732 * Put reference to dquot 733 */ 734 void dqput(struct dquot *dquot) 735 { 736 int ret; 737 738 if (!dquot) 739 return; 740 #ifdef CONFIG_QUOTA_DEBUG 741 if (!atomic_read(&dquot->dq_count)) { 742 quota_error(dquot->dq_sb, "trying to free free dquot of %s %d", 743 quotatypes[dquot->dq_id.type], 744 from_kqid(&init_user_ns, dquot->dq_id)); 745 BUG(); 746 } 747 #endif 748 dqstats_inc(DQST_DROPS); 749 we_slept: 750 spin_lock(&dq_list_lock); 751 if (atomic_read(&dquot->dq_count) > 1) { 752 /* We have more than one user... nothing to do */ 753 atomic_dec(&dquot->dq_count); 754 /* Releasing dquot during quotaoff phase? */ 755 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_id.type) && 756 atomic_read(&dquot->dq_count) == 1) 757 wake_up(&dquot->dq_wait_unused); 758 spin_unlock(&dq_list_lock); 759 return; 760 } 761 /* Need to release dquot? */ 762 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { 763 spin_unlock(&dq_list_lock); 764 /* Commit dquot before releasing */ 765 ret = dquot->dq_sb->dq_op->write_dquot(dquot); 766 if (ret < 0) { 767 quota_error(dquot->dq_sb, "Can't write quota structure" 768 " (error %d). Quota may get out of sync!", 769 ret); 770 /* 771 * We clear dirty bit anyway, so that we avoid 772 * infinite loop here 773 */ 774 spin_lock(&dq_list_lock); 775 clear_dquot_dirty(dquot); 776 spin_unlock(&dq_list_lock); 777 } 778 goto we_slept; 779 } 780 /* Clear flag in case dquot was inactive (something bad happened) */ 781 clear_dquot_dirty(dquot); 782 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 783 spin_unlock(&dq_list_lock); 784 dquot->dq_sb->dq_op->release_dquot(dquot); 785 goto we_slept; 786 } 787 atomic_dec(&dquot->dq_count); 788 #ifdef CONFIG_QUOTA_DEBUG 789 /* sanity check */ 790 BUG_ON(!list_empty(&dquot->dq_free)); 791 #endif 792 put_dquot_last(dquot); 793 spin_unlock(&dq_list_lock); 794 } 795 EXPORT_SYMBOL(dqput); 796 797 struct dquot *dquot_alloc(struct super_block *sb, int type) 798 { 799 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); 800 } 801 EXPORT_SYMBOL(dquot_alloc); 802 803 static struct dquot *get_empty_dquot(struct super_block *sb, int type) 804 { 805 struct dquot *dquot; 806 807 dquot = sb->dq_op->alloc_dquot(sb, type); 808 if(!dquot) 809 return NULL; 810 811 mutex_init(&dquot->dq_lock); 812 INIT_LIST_HEAD(&dquot->dq_free); 813 INIT_LIST_HEAD(&dquot->dq_inuse); 814 INIT_HLIST_NODE(&dquot->dq_hash); 815 INIT_LIST_HEAD(&dquot->dq_dirty); 816 init_waitqueue_head(&dquot->dq_wait_unused); 817 dquot->dq_sb = sb; 818 dquot->dq_id = make_kqid_invalid(type); 819 atomic_set(&dquot->dq_count, 1); 820 821 return dquot; 822 } 823 824 /* 825 * Get reference to dquot 826 * 827 * Locking is slightly tricky here. We are guarded from parallel quotaoff() 828 * destroying our dquot by: 829 * a) checking for quota flags under dq_list_lock and 830 * b) getting a reference to dquot before we release dq_list_lock 831 */ 832 struct dquot *dqget(struct super_block *sb, struct kqid qid) 833 { 834 unsigned int hashent = hashfn(sb, qid); 835 struct dquot *dquot, *empty = NULL; 836 837 if (!sb_has_quota_active(sb, qid.type)) 838 return ERR_PTR(-ESRCH); 839 we_slept: 840 spin_lock(&dq_list_lock); 841 spin_lock(&dq_state_lock); 842 if (!sb_has_quota_active(sb, qid.type)) { 843 spin_unlock(&dq_state_lock); 844 spin_unlock(&dq_list_lock); 845 dquot = ERR_PTR(-ESRCH); 846 goto out; 847 } 848 spin_unlock(&dq_state_lock); 849 850 dquot = find_dquot(hashent, sb, qid); 851 if (!dquot) { 852 if (!empty) { 853 spin_unlock(&dq_list_lock); 854 empty = get_empty_dquot(sb, qid.type); 855 if (!empty) 856 schedule(); /* Try to wait for a moment... */ 857 goto we_slept; 858 } 859 dquot = empty; 860 empty = NULL; 861 dquot->dq_id = qid; 862 /* all dquots go on the inuse_list */ 863 put_inuse(dquot); 864 /* hash it first so it can be found */ 865 insert_dquot_hash(dquot); 866 spin_unlock(&dq_list_lock); 867 dqstats_inc(DQST_LOOKUPS); 868 } else { 869 if (!atomic_read(&dquot->dq_count)) 870 remove_free_dquot(dquot); 871 atomic_inc(&dquot->dq_count); 872 spin_unlock(&dq_list_lock); 873 dqstats_inc(DQST_CACHE_HITS); 874 dqstats_inc(DQST_LOOKUPS); 875 } 876 /* Wait for dq_lock - after this we know that either dquot_release() is 877 * already finished or it will be canceled due to dq_count > 1 test */ 878 wait_on_dquot(dquot); 879 /* Read the dquot / allocate space in quota file */ 880 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 881 int err; 882 883 err = sb->dq_op->acquire_dquot(dquot); 884 if (err < 0) { 885 dqput(dquot); 886 dquot = ERR_PTR(err); 887 goto out; 888 } 889 } 890 #ifdef CONFIG_QUOTA_DEBUG 891 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ 892 #endif 893 out: 894 if (empty) 895 do_destroy_dquot(empty); 896 897 return dquot; 898 } 899 EXPORT_SYMBOL(dqget); 900 901 static inline struct dquot **i_dquot(struct inode *inode) 902 { 903 return inode->i_sb->s_op->get_dquots(inode); 904 } 905 906 static int dqinit_needed(struct inode *inode, int type) 907 { 908 struct dquot * const *dquots; 909 int cnt; 910 911 if (IS_NOQUOTA(inode)) 912 return 0; 913 914 dquots = i_dquot(inode); 915 if (type != -1) 916 return !dquots[type]; 917 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 918 if (!dquots[cnt]) 919 return 1; 920 return 0; 921 } 922 923 /* This routine is guarded by dqonoff_mutex mutex */ 924 static void add_dquot_ref(struct super_block *sb, int type) 925 { 926 struct inode *inode, *old_inode = NULL; 927 #ifdef CONFIG_QUOTA_DEBUG 928 int reserved = 0; 929 #endif 930 931 spin_lock(&sb->s_inode_list_lock); 932 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 933 spin_lock(&inode->i_lock); 934 if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || 935 !atomic_read(&inode->i_writecount) || 936 !dqinit_needed(inode, type)) { 937 spin_unlock(&inode->i_lock); 938 continue; 939 } 940 __iget(inode); 941 spin_unlock(&inode->i_lock); 942 spin_unlock(&sb->s_inode_list_lock); 943 944 #ifdef CONFIG_QUOTA_DEBUG 945 if (unlikely(inode_get_rsv_space(inode) > 0)) 946 reserved = 1; 947 #endif 948 iput(old_inode); 949 __dquot_initialize(inode, type); 950 951 /* 952 * We hold a reference to 'inode' so it couldn't have been 953 * removed from s_inodes list while we dropped the 954 * s_inode_list_lock. We cannot iput the inode now as we can be 955 * holding the last reference and we cannot iput it under 956 * s_inode_list_lock. So we keep the reference and iput it 957 * later. 958 */ 959 old_inode = inode; 960 spin_lock(&sb->s_inode_list_lock); 961 } 962 spin_unlock(&sb->s_inode_list_lock); 963 iput(old_inode); 964 965 #ifdef CONFIG_QUOTA_DEBUG 966 if (reserved) { 967 quota_error(sb, "Writes happened before quota was turned on " 968 "thus quota information is probably inconsistent. " 969 "Please run quotacheck(8)"); 970 } 971 #endif 972 } 973 974 /* 975 * Remove references to dquots from inode and add dquot to list for freeing 976 * if we have the last reference to dquot 977 */ 978 static void remove_inode_dquot_ref(struct inode *inode, int type, 979 struct list_head *tofree_head) 980 { 981 struct dquot **dquots = i_dquot(inode); 982 struct dquot *dquot = dquots[type]; 983 984 if (!dquot) 985 return; 986 987 dquots[type] = NULL; 988 if (list_empty(&dquot->dq_free)) { 989 /* 990 * The inode still has reference to dquot so it can't be in the 991 * free list 992 */ 993 spin_lock(&dq_list_lock); 994 list_add(&dquot->dq_free, tofree_head); 995 spin_unlock(&dq_list_lock); 996 } else { 997 /* 998 * Dquot is already in a list to put so we won't drop the last 999 * reference here. 1000 */ 1001 dqput(dquot); 1002 } 1003 } 1004 1005 /* 1006 * Free list of dquots 1007 * Dquots are removed from inodes and no new references can be got so we are 1008 * the only ones holding reference 1009 */ 1010 static void put_dquot_list(struct list_head *tofree_head) 1011 { 1012 struct list_head *act_head; 1013 struct dquot *dquot; 1014 1015 act_head = tofree_head->next; 1016 while (act_head != tofree_head) { 1017 dquot = list_entry(act_head, struct dquot, dq_free); 1018 act_head = act_head->next; 1019 /* Remove dquot from the list so we won't have problems... */ 1020 list_del_init(&dquot->dq_free); 1021 dqput(dquot); 1022 } 1023 } 1024 1025 static void remove_dquot_ref(struct super_block *sb, int type, 1026 struct list_head *tofree_head) 1027 { 1028 struct inode *inode; 1029 int reserved = 0; 1030 1031 spin_lock(&sb->s_inode_list_lock); 1032 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 1033 /* 1034 * We have to scan also I_NEW inodes because they can already 1035 * have quota pointer initialized. Luckily, we need to touch 1036 * only quota pointers and these have separate locking 1037 * (dq_data_lock). 1038 */ 1039 spin_lock(&dq_data_lock); 1040 if (!IS_NOQUOTA(inode)) { 1041 if (unlikely(inode_get_rsv_space(inode) > 0)) 1042 reserved = 1; 1043 remove_inode_dquot_ref(inode, type, tofree_head); 1044 } 1045 spin_unlock(&dq_data_lock); 1046 } 1047 spin_unlock(&sb->s_inode_list_lock); 1048 #ifdef CONFIG_QUOTA_DEBUG 1049 if (reserved) { 1050 printk(KERN_WARNING "VFS (%s): Writes happened after quota" 1051 " was disabled thus quota information is probably " 1052 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 1053 } 1054 #endif 1055 } 1056 1057 /* Gather all references from inodes and drop them */ 1058 static void drop_dquot_ref(struct super_block *sb, int type) 1059 { 1060 LIST_HEAD(tofree_head); 1061 1062 if (sb->dq_op) { 1063 remove_dquot_ref(sb, type, &tofree_head); 1064 synchronize_srcu(&dquot_srcu); 1065 put_dquot_list(&tofree_head); 1066 } 1067 } 1068 1069 static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1070 { 1071 dquot->dq_dqb.dqb_curinodes += number; 1072 } 1073 1074 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1075 { 1076 dquot->dq_dqb.dqb_curspace += number; 1077 } 1078 1079 static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1080 { 1081 dquot->dq_dqb.dqb_rsvspace += number; 1082 } 1083 1084 /* 1085 * Claim reserved quota space 1086 */ 1087 static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1088 { 1089 if (dquot->dq_dqb.dqb_rsvspace < number) { 1090 WARN_ON_ONCE(1); 1091 number = dquot->dq_dqb.dqb_rsvspace; 1092 } 1093 dquot->dq_dqb.dqb_curspace += number; 1094 dquot->dq_dqb.dqb_rsvspace -= number; 1095 } 1096 1097 static void dquot_reclaim_reserved_space(struct dquot *dquot, qsize_t number) 1098 { 1099 if (WARN_ON_ONCE(dquot->dq_dqb.dqb_curspace < number)) 1100 number = dquot->dq_dqb.dqb_curspace; 1101 dquot->dq_dqb.dqb_rsvspace += number; 1102 dquot->dq_dqb.dqb_curspace -= number; 1103 } 1104 1105 static inline 1106 void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1107 { 1108 if (dquot->dq_dqb.dqb_rsvspace >= number) 1109 dquot->dq_dqb.dqb_rsvspace -= number; 1110 else { 1111 WARN_ON_ONCE(1); 1112 dquot->dq_dqb.dqb_rsvspace = 0; 1113 } 1114 } 1115 1116 static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1117 { 1118 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1119 dquot->dq_dqb.dqb_curinodes >= number) 1120 dquot->dq_dqb.dqb_curinodes -= number; 1121 else 1122 dquot->dq_dqb.dqb_curinodes = 0; 1123 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1124 dquot->dq_dqb.dqb_itime = (time_t) 0; 1125 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1126 } 1127 1128 static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1129 { 1130 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1131 dquot->dq_dqb.dqb_curspace >= number) 1132 dquot->dq_dqb.dqb_curspace -= number; 1133 else 1134 dquot->dq_dqb.dqb_curspace = 0; 1135 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1136 dquot->dq_dqb.dqb_btime = (time_t) 0; 1137 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1138 } 1139 1140 struct dquot_warn { 1141 struct super_block *w_sb; 1142 struct kqid w_dq_id; 1143 short w_type; 1144 }; 1145 1146 static int warning_issued(struct dquot *dquot, const int warntype) 1147 { 1148 int flag = (warntype == QUOTA_NL_BHARDWARN || 1149 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1150 ((warntype == QUOTA_NL_IHARDWARN || 1151 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1152 1153 if (!flag) 1154 return 0; 1155 return test_and_set_bit(flag, &dquot->dq_flags); 1156 } 1157 1158 #ifdef CONFIG_PRINT_QUOTA_WARNING 1159 static int flag_print_warnings = 1; 1160 1161 static int need_print_warning(struct dquot_warn *warn) 1162 { 1163 if (!flag_print_warnings) 1164 return 0; 1165 1166 switch (warn->w_dq_id.type) { 1167 case USRQUOTA: 1168 return uid_eq(current_fsuid(), warn->w_dq_id.uid); 1169 case GRPQUOTA: 1170 return in_group_p(warn->w_dq_id.gid); 1171 case PRJQUOTA: 1172 return 1; 1173 } 1174 return 0; 1175 } 1176 1177 /* Print warning to user which exceeded quota */ 1178 static void print_warning(struct dquot_warn *warn) 1179 { 1180 char *msg = NULL; 1181 struct tty_struct *tty; 1182 int warntype = warn->w_type; 1183 1184 if (warntype == QUOTA_NL_IHARDBELOW || 1185 warntype == QUOTA_NL_ISOFTBELOW || 1186 warntype == QUOTA_NL_BHARDBELOW || 1187 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(warn)) 1188 return; 1189 1190 tty = get_current_tty(); 1191 if (!tty) 1192 return; 1193 tty_write_message(tty, warn->w_sb->s_id); 1194 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1195 tty_write_message(tty, ": warning, "); 1196 else 1197 tty_write_message(tty, ": write failed, "); 1198 tty_write_message(tty, quotatypes[warn->w_dq_id.type]); 1199 switch (warntype) { 1200 case QUOTA_NL_IHARDWARN: 1201 msg = " file limit reached.\r\n"; 1202 break; 1203 case QUOTA_NL_ISOFTLONGWARN: 1204 msg = " file quota exceeded too long.\r\n"; 1205 break; 1206 case QUOTA_NL_ISOFTWARN: 1207 msg = " file quota exceeded.\r\n"; 1208 break; 1209 case QUOTA_NL_BHARDWARN: 1210 msg = " block limit reached.\r\n"; 1211 break; 1212 case QUOTA_NL_BSOFTLONGWARN: 1213 msg = " block quota exceeded too long.\r\n"; 1214 break; 1215 case QUOTA_NL_BSOFTWARN: 1216 msg = " block quota exceeded.\r\n"; 1217 break; 1218 } 1219 tty_write_message(tty, msg); 1220 tty_kref_put(tty); 1221 } 1222 #endif 1223 1224 static void prepare_warning(struct dquot_warn *warn, struct dquot *dquot, 1225 int warntype) 1226 { 1227 if (warning_issued(dquot, warntype)) 1228 return; 1229 warn->w_type = warntype; 1230 warn->w_sb = dquot->dq_sb; 1231 warn->w_dq_id = dquot->dq_id; 1232 } 1233 1234 /* 1235 * Write warnings to the console and send warning messages over netlink. 1236 * 1237 * Note that this function can call into tty and networking code. 1238 */ 1239 static void flush_warnings(struct dquot_warn *warn) 1240 { 1241 int i; 1242 1243 for (i = 0; i < MAXQUOTAS; i++) { 1244 if (warn[i].w_type == QUOTA_NL_NOWARN) 1245 continue; 1246 #ifdef CONFIG_PRINT_QUOTA_WARNING 1247 print_warning(&warn[i]); 1248 #endif 1249 quota_send_warning(warn[i].w_dq_id, 1250 warn[i].w_sb->s_dev, warn[i].w_type); 1251 } 1252 } 1253 1254 static int ignore_hardlimit(struct dquot *dquot) 1255 { 1256 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 1257 1258 return capable(CAP_SYS_RESOURCE) && 1259 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1260 !(info->dqi_flags & DQF_ROOT_SQUASH)); 1261 } 1262 1263 /* needs dq_data_lock */ 1264 static int check_idq(struct dquot *dquot, qsize_t inodes, 1265 struct dquot_warn *warn) 1266 { 1267 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1268 1269 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type) || 1270 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1271 return 0; 1272 1273 if (dquot->dq_dqb.dqb_ihardlimit && 1274 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1275 !ignore_hardlimit(dquot)) { 1276 prepare_warning(warn, dquot, QUOTA_NL_IHARDWARN); 1277 return -EDQUOT; 1278 } 1279 1280 if (dquot->dq_dqb.dqb_isoftlimit && 1281 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1282 dquot->dq_dqb.dqb_itime && 1283 get_seconds() >= dquot->dq_dqb.dqb_itime && 1284 !ignore_hardlimit(dquot)) { 1285 prepare_warning(warn, dquot, QUOTA_NL_ISOFTLONGWARN); 1286 return -EDQUOT; 1287 } 1288 1289 if (dquot->dq_dqb.dqb_isoftlimit && 1290 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1291 dquot->dq_dqb.dqb_itime == 0) { 1292 prepare_warning(warn, dquot, QUOTA_NL_ISOFTWARN); 1293 dquot->dq_dqb.dqb_itime = get_seconds() + 1294 sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type].dqi_igrace; 1295 } 1296 1297 return 0; 1298 } 1299 1300 /* needs dq_data_lock */ 1301 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, 1302 struct dquot_warn *warn) 1303 { 1304 qsize_t tspace; 1305 struct super_block *sb = dquot->dq_sb; 1306 1307 if (!sb_has_quota_limits_enabled(sb, dquot->dq_id.type) || 1308 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1309 return 0; 1310 1311 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1312 + space; 1313 1314 if (dquot->dq_dqb.dqb_bhardlimit && 1315 tspace > dquot->dq_dqb.dqb_bhardlimit && 1316 !ignore_hardlimit(dquot)) { 1317 if (!prealloc) 1318 prepare_warning(warn, dquot, QUOTA_NL_BHARDWARN); 1319 return -EDQUOT; 1320 } 1321 1322 if (dquot->dq_dqb.dqb_bsoftlimit && 1323 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1324 dquot->dq_dqb.dqb_btime && 1325 get_seconds() >= dquot->dq_dqb.dqb_btime && 1326 !ignore_hardlimit(dquot)) { 1327 if (!prealloc) 1328 prepare_warning(warn, dquot, QUOTA_NL_BSOFTLONGWARN); 1329 return -EDQUOT; 1330 } 1331 1332 if (dquot->dq_dqb.dqb_bsoftlimit && 1333 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1334 dquot->dq_dqb.dqb_btime == 0) { 1335 if (!prealloc) { 1336 prepare_warning(warn, dquot, QUOTA_NL_BSOFTWARN); 1337 dquot->dq_dqb.dqb_btime = get_seconds() + 1338 sb_dqopt(sb)->info[dquot->dq_id.type].dqi_bgrace; 1339 } 1340 else 1341 /* 1342 * We don't allow preallocation to exceed softlimit so exceeding will 1343 * be always printed 1344 */ 1345 return -EDQUOT; 1346 } 1347 1348 return 0; 1349 } 1350 1351 static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1352 { 1353 qsize_t newinodes; 1354 1355 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1356 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1357 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type)) 1358 return QUOTA_NL_NOWARN; 1359 1360 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1361 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1362 return QUOTA_NL_ISOFTBELOW; 1363 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1364 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1365 return QUOTA_NL_IHARDBELOW; 1366 return QUOTA_NL_NOWARN; 1367 } 1368 1369 static int info_bdq_free(struct dquot *dquot, qsize_t space) 1370 { 1371 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1372 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1373 return QUOTA_NL_NOWARN; 1374 1375 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1376 return QUOTA_NL_BSOFTBELOW; 1377 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1378 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1379 return QUOTA_NL_BHARDBELOW; 1380 return QUOTA_NL_NOWARN; 1381 } 1382 1383 static int dquot_active(const struct inode *inode) 1384 { 1385 struct super_block *sb = inode->i_sb; 1386 1387 if (IS_NOQUOTA(inode)) 1388 return 0; 1389 return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb); 1390 } 1391 1392 /* 1393 * Initialize quota pointers in inode 1394 * 1395 * It is better to call this function outside of any transaction as it 1396 * might need a lot of space in journal for dquot structure allocation. 1397 */ 1398 static int __dquot_initialize(struct inode *inode, int type) 1399 { 1400 int cnt, init_needed = 0; 1401 struct dquot **dquots, *got[MAXQUOTAS]; 1402 struct super_block *sb = inode->i_sb; 1403 qsize_t rsv; 1404 int ret = 0; 1405 1406 if (!dquot_active(inode)) 1407 return 0; 1408 1409 dquots = i_dquot(inode); 1410 1411 /* First get references to structures we might need. */ 1412 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1413 struct kqid qid; 1414 kprojid_t projid; 1415 int rc; 1416 struct dquot *dquot; 1417 1418 got[cnt] = NULL; 1419 if (type != -1 && cnt != type) 1420 continue; 1421 /* 1422 * The i_dquot should have been initialized in most cases, 1423 * we check it without locking here to avoid unnecessary 1424 * dqget()/dqput() calls. 1425 */ 1426 if (dquots[cnt]) 1427 continue; 1428 1429 if (!sb_has_quota_active(sb, cnt)) 1430 continue; 1431 1432 init_needed = 1; 1433 1434 switch (cnt) { 1435 case USRQUOTA: 1436 qid = make_kqid_uid(inode->i_uid); 1437 break; 1438 case GRPQUOTA: 1439 qid = make_kqid_gid(inode->i_gid); 1440 break; 1441 case PRJQUOTA: 1442 rc = inode->i_sb->dq_op->get_projid(inode, &projid); 1443 if (rc) 1444 continue; 1445 qid = make_kqid_projid(projid); 1446 break; 1447 } 1448 dquot = dqget(sb, qid); 1449 if (IS_ERR(dquot)) { 1450 /* We raced with somebody turning quotas off... */ 1451 if (PTR_ERR(dquot) != -ESRCH) { 1452 ret = PTR_ERR(dquot); 1453 goto out_put; 1454 } 1455 dquot = NULL; 1456 } 1457 got[cnt] = dquot; 1458 } 1459 1460 /* All required i_dquot has been initialized */ 1461 if (!init_needed) 1462 return 0; 1463 1464 spin_lock(&dq_data_lock); 1465 if (IS_NOQUOTA(inode)) 1466 goto out_lock; 1467 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1468 if (type != -1 && cnt != type) 1469 continue; 1470 /* Avoid races with quotaoff() */ 1471 if (!sb_has_quota_active(sb, cnt)) 1472 continue; 1473 /* We could race with quotaon or dqget() could have failed */ 1474 if (!got[cnt]) 1475 continue; 1476 if (!dquots[cnt]) { 1477 dquots[cnt] = got[cnt]; 1478 got[cnt] = NULL; 1479 /* 1480 * Make quota reservation system happy if someone 1481 * did a write before quota was turned on 1482 */ 1483 rsv = inode_get_rsv_space(inode); 1484 if (unlikely(rsv)) 1485 dquot_resv_space(dquots[cnt], rsv); 1486 } 1487 } 1488 out_lock: 1489 spin_unlock(&dq_data_lock); 1490 out_put: 1491 /* Drop unused references */ 1492 dqput_all(got); 1493 1494 return ret; 1495 } 1496 1497 int dquot_initialize(struct inode *inode) 1498 { 1499 return __dquot_initialize(inode, -1); 1500 } 1501 EXPORT_SYMBOL(dquot_initialize); 1502 1503 /* 1504 * Release all quotas referenced by inode. 1505 * 1506 * This function only be called on inode free or converting 1507 * a file to quota file, no other users for the i_dquot in 1508 * both cases, so we needn't call synchronize_srcu() after 1509 * clearing i_dquot. 1510 */ 1511 static void __dquot_drop(struct inode *inode) 1512 { 1513 int cnt; 1514 struct dquot **dquots = i_dquot(inode); 1515 struct dquot *put[MAXQUOTAS]; 1516 1517 spin_lock(&dq_data_lock); 1518 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1519 put[cnt] = dquots[cnt]; 1520 dquots[cnt] = NULL; 1521 } 1522 spin_unlock(&dq_data_lock); 1523 dqput_all(put); 1524 } 1525 1526 void dquot_drop(struct inode *inode) 1527 { 1528 struct dquot * const *dquots; 1529 int cnt; 1530 1531 if (IS_NOQUOTA(inode)) 1532 return; 1533 1534 /* 1535 * Test before calling to rule out calls from proc and such 1536 * where we are not allowed to block. Note that this is 1537 * actually reliable test even without the lock - the caller 1538 * must assure that nobody can come after the DQUOT_DROP and 1539 * add quota pointers back anyway. 1540 */ 1541 dquots = i_dquot(inode); 1542 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1543 if (dquots[cnt]) 1544 break; 1545 } 1546 1547 if (cnt < MAXQUOTAS) 1548 __dquot_drop(inode); 1549 } 1550 EXPORT_SYMBOL(dquot_drop); 1551 1552 /* 1553 * inode_reserved_space is managed internally by quota, and protected by 1554 * i_lock similar to i_blocks+i_bytes. 1555 */ 1556 static qsize_t *inode_reserved_space(struct inode * inode) 1557 { 1558 /* Filesystem must explicitly define it's own method in order to use 1559 * quota reservation interface */ 1560 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1561 return inode->i_sb->dq_op->get_reserved_space(inode); 1562 } 1563 1564 void inode_add_rsv_space(struct inode *inode, qsize_t number) 1565 { 1566 spin_lock(&inode->i_lock); 1567 *inode_reserved_space(inode) += number; 1568 spin_unlock(&inode->i_lock); 1569 } 1570 EXPORT_SYMBOL(inode_add_rsv_space); 1571 1572 void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1573 { 1574 spin_lock(&inode->i_lock); 1575 *inode_reserved_space(inode) -= number; 1576 __inode_add_bytes(inode, number); 1577 spin_unlock(&inode->i_lock); 1578 } 1579 EXPORT_SYMBOL(inode_claim_rsv_space); 1580 1581 void inode_reclaim_rsv_space(struct inode *inode, qsize_t number) 1582 { 1583 spin_lock(&inode->i_lock); 1584 *inode_reserved_space(inode) += number; 1585 __inode_sub_bytes(inode, number); 1586 spin_unlock(&inode->i_lock); 1587 } 1588 EXPORT_SYMBOL(inode_reclaim_rsv_space); 1589 1590 void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1591 { 1592 spin_lock(&inode->i_lock); 1593 *inode_reserved_space(inode) -= number; 1594 spin_unlock(&inode->i_lock); 1595 } 1596 EXPORT_SYMBOL(inode_sub_rsv_space); 1597 1598 static qsize_t inode_get_rsv_space(struct inode *inode) 1599 { 1600 qsize_t ret; 1601 1602 if (!inode->i_sb->dq_op->get_reserved_space) 1603 return 0; 1604 spin_lock(&inode->i_lock); 1605 ret = *inode_reserved_space(inode); 1606 spin_unlock(&inode->i_lock); 1607 return ret; 1608 } 1609 1610 static void inode_incr_space(struct inode *inode, qsize_t number, 1611 int reserve) 1612 { 1613 if (reserve) 1614 inode_add_rsv_space(inode, number); 1615 else 1616 inode_add_bytes(inode, number); 1617 } 1618 1619 static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1620 { 1621 if (reserve) 1622 inode_sub_rsv_space(inode, number); 1623 else 1624 inode_sub_bytes(inode, number); 1625 } 1626 1627 /* 1628 * This functions updates i_blocks+i_bytes fields and quota information 1629 * (together with appropriate checks). 1630 * 1631 * NOTE: We absolutely rely on the fact that caller dirties the inode 1632 * (usually helpers in quotaops.h care about this) and holds a handle for 1633 * the current transaction so that dquot write and inode write go into the 1634 * same transaction. 1635 */ 1636 1637 /* 1638 * This operation can block, but only after everything is updated 1639 */ 1640 int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags) 1641 { 1642 int cnt, ret = 0, index; 1643 struct dquot_warn warn[MAXQUOTAS]; 1644 int reserve = flags & DQUOT_SPACE_RESERVE; 1645 struct dquot **dquots; 1646 1647 if (!dquot_active(inode)) { 1648 inode_incr_space(inode, number, reserve); 1649 goto out; 1650 } 1651 1652 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1653 warn[cnt].w_type = QUOTA_NL_NOWARN; 1654 1655 dquots = i_dquot(inode); 1656 index = srcu_read_lock(&dquot_srcu); 1657 spin_lock(&dq_data_lock); 1658 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1659 if (!dquots[cnt]) 1660 continue; 1661 ret = check_bdq(dquots[cnt], number, 1662 !(flags & DQUOT_SPACE_WARN), &warn[cnt]); 1663 if (ret && !(flags & DQUOT_SPACE_NOFAIL)) { 1664 spin_unlock(&dq_data_lock); 1665 goto out_flush_warn; 1666 } 1667 } 1668 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1669 if (!dquots[cnt]) 1670 continue; 1671 if (reserve) 1672 dquot_resv_space(dquots[cnt], number); 1673 else 1674 dquot_incr_space(dquots[cnt], number); 1675 } 1676 inode_incr_space(inode, number, reserve); 1677 spin_unlock(&dq_data_lock); 1678 1679 if (reserve) 1680 goto out_flush_warn; 1681 mark_all_dquot_dirty(dquots); 1682 out_flush_warn: 1683 srcu_read_unlock(&dquot_srcu, index); 1684 flush_warnings(warn); 1685 out: 1686 return ret; 1687 } 1688 EXPORT_SYMBOL(__dquot_alloc_space); 1689 1690 /* 1691 * This operation can block, but only after everything is updated 1692 */ 1693 int dquot_alloc_inode(struct inode *inode) 1694 { 1695 int cnt, ret = 0, index; 1696 struct dquot_warn warn[MAXQUOTAS]; 1697 struct dquot * const *dquots; 1698 1699 if (!dquot_active(inode)) 1700 return 0; 1701 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1702 warn[cnt].w_type = QUOTA_NL_NOWARN; 1703 1704 dquots = i_dquot(inode); 1705 index = srcu_read_lock(&dquot_srcu); 1706 spin_lock(&dq_data_lock); 1707 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1708 if (!dquots[cnt]) 1709 continue; 1710 ret = check_idq(dquots[cnt], 1, &warn[cnt]); 1711 if (ret) 1712 goto warn_put_all; 1713 } 1714 1715 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1716 if (!dquots[cnt]) 1717 continue; 1718 dquot_incr_inodes(dquots[cnt], 1); 1719 } 1720 1721 warn_put_all: 1722 spin_unlock(&dq_data_lock); 1723 if (ret == 0) 1724 mark_all_dquot_dirty(dquots); 1725 srcu_read_unlock(&dquot_srcu, index); 1726 flush_warnings(warn); 1727 return ret; 1728 } 1729 EXPORT_SYMBOL(dquot_alloc_inode); 1730 1731 /* 1732 * Convert in-memory reserved quotas to real consumed quotas 1733 */ 1734 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1735 { 1736 struct dquot **dquots; 1737 int cnt, index; 1738 1739 if (!dquot_active(inode)) { 1740 inode_claim_rsv_space(inode, number); 1741 return 0; 1742 } 1743 1744 dquots = i_dquot(inode); 1745 index = srcu_read_lock(&dquot_srcu); 1746 spin_lock(&dq_data_lock); 1747 /* Claim reserved quotas to allocated quotas */ 1748 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1749 if (dquots[cnt]) 1750 dquot_claim_reserved_space(dquots[cnt], number); 1751 } 1752 /* Update inode bytes */ 1753 inode_claim_rsv_space(inode, number); 1754 spin_unlock(&dq_data_lock); 1755 mark_all_dquot_dirty(dquots); 1756 srcu_read_unlock(&dquot_srcu, index); 1757 return 0; 1758 } 1759 EXPORT_SYMBOL(dquot_claim_space_nodirty); 1760 1761 /* 1762 * Convert allocated space back to in-memory reserved quotas 1763 */ 1764 void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number) 1765 { 1766 struct dquot **dquots; 1767 int cnt, index; 1768 1769 if (!dquot_active(inode)) { 1770 inode_reclaim_rsv_space(inode, number); 1771 return; 1772 } 1773 1774 dquots = i_dquot(inode); 1775 index = srcu_read_lock(&dquot_srcu); 1776 spin_lock(&dq_data_lock); 1777 /* Claim reserved quotas to allocated quotas */ 1778 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1779 if (dquots[cnt]) 1780 dquot_reclaim_reserved_space(dquots[cnt], number); 1781 } 1782 /* Update inode bytes */ 1783 inode_reclaim_rsv_space(inode, number); 1784 spin_unlock(&dq_data_lock); 1785 mark_all_dquot_dirty(dquots); 1786 srcu_read_unlock(&dquot_srcu, index); 1787 return; 1788 } 1789 EXPORT_SYMBOL(dquot_reclaim_space_nodirty); 1790 1791 /* 1792 * This operation can block, but only after everything is updated 1793 */ 1794 void __dquot_free_space(struct inode *inode, qsize_t number, int flags) 1795 { 1796 unsigned int cnt; 1797 struct dquot_warn warn[MAXQUOTAS]; 1798 struct dquot **dquots; 1799 int reserve = flags & DQUOT_SPACE_RESERVE, index; 1800 1801 if (!dquot_active(inode)) { 1802 inode_decr_space(inode, number, reserve); 1803 return; 1804 } 1805 1806 dquots = i_dquot(inode); 1807 index = srcu_read_lock(&dquot_srcu); 1808 spin_lock(&dq_data_lock); 1809 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1810 int wtype; 1811 1812 warn[cnt].w_type = QUOTA_NL_NOWARN; 1813 if (!dquots[cnt]) 1814 continue; 1815 wtype = info_bdq_free(dquots[cnt], number); 1816 if (wtype != QUOTA_NL_NOWARN) 1817 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1818 if (reserve) 1819 dquot_free_reserved_space(dquots[cnt], number); 1820 else 1821 dquot_decr_space(dquots[cnt], number); 1822 } 1823 inode_decr_space(inode, number, reserve); 1824 spin_unlock(&dq_data_lock); 1825 1826 if (reserve) 1827 goto out_unlock; 1828 mark_all_dquot_dirty(dquots); 1829 out_unlock: 1830 srcu_read_unlock(&dquot_srcu, index); 1831 flush_warnings(warn); 1832 } 1833 EXPORT_SYMBOL(__dquot_free_space); 1834 1835 /* 1836 * This operation can block, but only after everything is updated 1837 */ 1838 void dquot_free_inode(struct inode *inode) 1839 { 1840 unsigned int cnt; 1841 struct dquot_warn warn[MAXQUOTAS]; 1842 struct dquot * const *dquots; 1843 int index; 1844 1845 if (!dquot_active(inode)) 1846 return; 1847 1848 dquots = i_dquot(inode); 1849 index = srcu_read_lock(&dquot_srcu); 1850 spin_lock(&dq_data_lock); 1851 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1852 int wtype; 1853 1854 warn[cnt].w_type = QUOTA_NL_NOWARN; 1855 if (!dquots[cnt]) 1856 continue; 1857 wtype = info_idq_free(dquots[cnt], 1); 1858 if (wtype != QUOTA_NL_NOWARN) 1859 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1860 dquot_decr_inodes(dquots[cnt], 1); 1861 } 1862 spin_unlock(&dq_data_lock); 1863 mark_all_dquot_dirty(dquots); 1864 srcu_read_unlock(&dquot_srcu, index); 1865 flush_warnings(warn); 1866 } 1867 EXPORT_SYMBOL(dquot_free_inode); 1868 1869 /* 1870 * Transfer the number of inode and blocks from one diskquota to an other. 1871 * On success, dquot references in transfer_to are consumed and references 1872 * to original dquots that need to be released are placed there. On failure, 1873 * references are kept untouched. 1874 * 1875 * This operation can block, but only after everything is updated 1876 * A transaction must be started when entering this function. 1877 * 1878 * We are holding reference on transfer_from & transfer_to, no need to 1879 * protect them by srcu_read_lock(). 1880 */ 1881 int __dquot_transfer(struct inode *inode, struct dquot **transfer_to) 1882 { 1883 qsize_t space, cur_space; 1884 qsize_t rsv_space = 0; 1885 struct dquot *transfer_from[MAXQUOTAS] = {}; 1886 int cnt, ret = 0; 1887 char is_valid[MAXQUOTAS] = {}; 1888 struct dquot_warn warn_to[MAXQUOTAS]; 1889 struct dquot_warn warn_from_inodes[MAXQUOTAS]; 1890 struct dquot_warn warn_from_space[MAXQUOTAS]; 1891 1892 if (IS_NOQUOTA(inode)) 1893 return 0; 1894 /* Initialize the arrays */ 1895 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1896 warn_to[cnt].w_type = QUOTA_NL_NOWARN; 1897 warn_from_inodes[cnt].w_type = QUOTA_NL_NOWARN; 1898 warn_from_space[cnt].w_type = QUOTA_NL_NOWARN; 1899 } 1900 1901 spin_lock(&dq_data_lock); 1902 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1903 spin_unlock(&dq_data_lock); 1904 return 0; 1905 } 1906 cur_space = inode_get_bytes(inode); 1907 rsv_space = inode_get_rsv_space(inode); 1908 space = cur_space + rsv_space; 1909 /* Build the transfer_from list and check the limits */ 1910 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1911 /* 1912 * Skip changes for same uid or gid or for turned off quota-type. 1913 */ 1914 if (!transfer_to[cnt]) 1915 continue; 1916 /* Avoid races with quotaoff() */ 1917 if (!sb_has_quota_active(inode->i_sb, cnt)) 1918 continue; 1919 is_valid[cnt] = 1; 1920 transfer_from[cnt] = i_dquot(inode)[cnt]; 1921 ret = check_idq(transfer_to[cnt], 1, &warn_to[cnt]); 1922 if (ret) 1923 goto over_quota; 1924 ret = check_bdq(transfer_to[cnt], space, 0, &warn_to[cnt]); 1925 if (ret) 1926 goto over_quota; 1927 } 1928 1929 /* 1930 * Finally perform the needed transfer from transfer_from to transfer_to 1931 */ 1932 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1933 if (!is_valid[cnt]) 1934 continue; 1935 /* Due to IO error we might not have transfer_from[] structure */ 1936 if (transfer_from[cnt]) { 1937 int wtype; 1938 wtype = info_idq_free(transfer_from[cnt], 1); 1939 if (wtype != QUOTA_NL_NOWARN) 1940 prepare_warning(&warn_from_inodes[cnt], 1941 transfer_from[cnt], wtype); 1942 wtype = info_bdq_free(transfer_from[cnt], space); 1943 if (wtype != QUOTA_NL_NOWARN) 1944 prepare_warning(&warn_from_space[cnt], 1945 transfer_from[cnt], wtype); 1946 dquot_decr_inodes(transfer_from[cnt], 1); 1947 dquot_decr_space(transfer_from[cnt], cur_space); 1948 dquot_free_reserved_space(transfer_from[cnt], 1949 rsv_space); 1950 } 1951 1952 dquot_incr_inodes(transfer_to[cnt], 1); 1953 dquot_incr_space(transfer_to[cnt], cur_space); 1954 dquot_resv_space(transfer_to[cnt], rsv_space); 1955 1956 i_dquot(inode)[cnt] = transfer_to[cnt]; 1957 } 1958 spin_unlock(&dq_data_lock); 1959 1960 mark_all_dquot_dirty(transfer_from); 1961 mark_all_dquot_dirty(transfer_to); 1962 flush_warnings(warn_to); 1963 flush_warnings(warn_from_inodes); 1964 flush_warnings(warn_from_space); 1965 /* Pass back references to put */ 1966 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1967 if (is_valid[cnt]) 1968 transfer_to[cnt] = transfer_from[cnt]; 1969 return 0; 1970 over_quota: 1971 spin_unlock(&dq_data_lock); 1972 flush_warnings(warn_to); 1973 return ret; 1974 } 1975 EXPORT_SYMBOL(__dquot_transfer); 1976 1977 /* Wrapper for transferring ownership of an inode for uid/gid only 1978 * Called from FSXXX_setattr() 1979 */ 1980 int dquot_transfer(struct inode *inode, struct iattr *iattr) 1981 { 1982 struct dquot *transfer_to[MAXQUOTAS] = {}; 1983 struct dquot *dquot; 1984 struct super_block *sb = inode->i_sb; 1985 int ret; 1986 1987 if (!dquot_active(inode)) 1988 return 0; 1989 1990 if (iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)){ 1991 dquot = dqget(sb, make_kqid_uid(iattr->ia_uid)); 1992 if (IS_ERR(dquot)) { 1993 if (PTR_ERR(dquot) != -ESRCH) { 1994 ret = PTR_ERR(dquot); 1995 goto out_put; 1996 } 1997 dquot = NULL; 1998 } 1999 transfer_to[USRQUOTA] = dquot; 2000 } 2001 if (iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid)){ 2002 dquot = dqget(sb, make_kqid_gid(iattr->ia_gid)); 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[GRPQUOTA] = dquot; 2011 } 2012 ret = __dquot_transfer(inode, transfer_to); 2013 out_put: 2014 dqput_all(transfer_to); 2015 return ret; 2016 } 2017 EXPORT_SYMBOL(dquot_transfer); 2018 2019 /* 2020 * Write info of quota file to disk 2021 */ 2022 int dquot_commit_info(struct super_block *sb, int type) 2023 { 2024 int ret; 2025 struct quota_info *dqopt = sb_dqopt(sb); 2026 2027 mutex_lock(&dqopt->dqio_mutex); 2028 ret = dqopt->ops[type]->write_file_info(sb, type); 2029 mutex_unlock(&dqopt->dqio_mutex); 2030 return ret; 2031 } 2032 EXPORT_SYMBOL(dquot_commit_info); 2033 2034 int dquot_get_next_id(struct super_block *sb, struct kqid *qid) 2035 { 2036 struct quota_info *dqopt = sb_dqopt(sb); 2037 int err; 2038 2039 if (!dqopt->ops[qid->type]->get_next_id) 2040 return -ENOSYS; 2041 mutex_lock(&dqopt->dqio_mutex); 2042 err = dqopt->ops[qid->type]->get_next_id(sb, qid); 2043 mutex_unlock(&dqopt->dqio_mutex); 2044 2045 return err; 2046 } 2047 EXPORT_SYMBOL(dquot_get_next_id); 2048 2049 /* 2050 * Definitions of diskquota operations. 2051 */ 2052 const struct dquot_operations dquot_operations = { 2053 .write_dquot = dquot_commit, 2054 .acquire_dquot = dquot_acquire, 2055 .release_dquot = dquot_release, 2056 .mark_dirty = dquot_mark_dquot_dirty, 2057 .write_info = dquot_commit_info, 2058 .alloc_dquot = dquot_alloc, 2059 .destroy_dquot = dquot_destroy, 2060 .get_next_id = dquot_get_next_id, 2061 }; 2062 EXPORT_SYMBOL(dquot_operations); 2063 2064 /* 2065 * Generic helper for ->open on filesystems supporting disk quotas. 2066 */ 2067 int dquot_file_open(struct inode *inode, struct file *file) 2068 { 2069 int error; 2070 2071 error = generic_file_open(inode, file); 2072 if (!error && (file->f_mode & FMODE_WRITE)) 2073 dquot_initialize(inode); 2074 return error; 2075 } 2076 EXPORT_SYMBOL(dquot_file_open); 2077 2078 /* 2079 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 2080 */ 2081 int dquot_disable(struct super_block *sb, int type, unsigned int flags) 2082 { 2083 int cnt, ret = 0; 2084 struct quota_info *dqopt = sb_dqopt(sb); 2085 struct inode *toputinode[MAXQUOTAS]; 2086 2087 /* Cannot turn off usage accounting without turning off limits, or 2088 * suspend quotas and simultaneously turn quotas off. */ 2089 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 2090 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 2091 DQUOT_USAGE_ENABLED))) 2092 return -EINVAL; 2093 2094 /* We need to serialize quota_off() for device */ 2095 mutex_lock(&dqopt->dqonoff_mutex); 2096 2097 /* 2098 * Skip everything if there's nothing to do. We have to do this because 2099 * sometimes we are called when fill_super() failed and calling 2100 * sync_fs() in such cases does no good. 2101 */ 2102 if (!sb_any_quota_loaded(sb)) { 2103 mutex_unlock(&dqopt->dqonoff_mutex); 2104 return 0; 2105 } 2106 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2107 toputinode[cnt] = NULL; 2108 if (type != -1 && cnt != type) 2109 continue; 2110 if (!sb_has_quota_loaded(sb, cnt)) 2111 continue; 2112 2113 if (flags & DQUOT_SUSPENDED) { 2114 spin_lock(&dq_state_lock); 2115 dqopt->flags |= 2116 dquot_state_flag(DQUOT_SUSPENDED, cnt); 2117 spin_unlock(&dq_state_lock); 2118 } else { 2119 spin_lock(&dq_state_lock); 2120 dqopt->flags &= ~dquot_state_flag(flags, cnt); 2121 /* Turning off suspended quotas? */ 2122 if (!sb_has_quota_loaded(sb, cnt) && 2123 sb_has_quota_suspended(sb, cnt)) { 2124 dqopt->flags &= ~dquot_state_flag( 2125 DQUOT_SUSPENDED, cnt); 2126 spin_unlock(&dq_state_lock); 2127 iput(dqopt->files[cnt]); 2128 dqopt->files[cnt] = NULL; 2129 continue; 2130 } 2131 spin_unlock(&dq_state_lock); 2132 } 2133 2134 /* We still have to keep quota loaded? */ 2135 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 2136 continue; 2137 2138 /* Note: these are blocking operations */ 2139 drop_dquot_ref(sb, cnt); 2140 invalidate_dquots(sb, cnt); 2141 /* 2142 * Now all dquots should be invalidated, all writes done so we 2143 * should be only users of the info. No locks needed. 2144 */ 2145 if (info_dirty(&dqopt->info[cnt])) 2146 sb->dq_op->write_info(sb, cnt); 2147 if (dqopt->ops[cnt]->free_file_info) 2148 dqopt->ops[cnt]->free_file_info(sb, cnt); 2149 put_quota_format(dqopt->info[cnt].dqi_format); 2150 2151 toputinode[cnt] = dqopt->files[cnt]; 2152 if (!sb_has_quota_loaded(sb, cnt)) 2153 dqopt->files[cnt] = NULL; 2154 dqopt->info[cnt].dqi_flags = 0; 2155 dqopt->info[cnt].dqi_igrace = 0; 2156 dqopt->info[cnt].dqi_bgrace = 0; 2157 dqopt->ops[cnt] = NULL; 2158 } 2159 mutex_unlock(&dqopt->dqonoff_mutex); 2160 2161 /* Skip syncing and setting flags if quota files are hidden */ 2162 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2163 goto put_inodes; 2164 2165 /* Sync the superblock so that buffers with quota data are written to 2166 * disk (and so userspace sees correct data afterwards). */ 2167 if (sb->s_op->sync_fs) 2168 sb->s_op->sync_fs(sb, 1); 2169 sync_blockdev(sb->s_bdev); 2170 /* Now the quota files are just ordinary files and we can set the 2171 * inode flags back. Moreover we discard the pagecache so that 2172 * userspace sees the writes we did bypassing the pagecache. We 2173 * must also discard the blockdev buffers so that we see the 2174 * changes done by userspace on the next quotaon() */ 2175 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2176 if (toputinode[cnt]) { 2177 mutex_lock(&dqopt->dqonoff_mutex); 2178 /* If quota was reenabled in the meantime, we have 2179 * nothing to do */ 2180 if (!sb_has_quota_loaded(sb, cnt)) { 2181 inode_lock(toputinode[cnt]); 2182 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 2183 S_NOATIME | S_NOQUOTA); 2184 truncate_inode_pages(&toputinode[cnt]->i_data, 2185 0); 2186 inode_unlock(toputinode[cnt]); 2187 mark_inode_dirty_sync(toputinode[cnt]); 2188 } 2189 mutex_unlock(&dqopt->dqonoff_mutex); 2190 } 2191 if (sb->s_bdev) 2192 invalidate_bdev(sb->s_bdev); 2193 put_inodes: 2194 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2195 if (toputinode[cnt]) { 2196 /* On remount RO, we keep the inode pointer so that we 2197 * can reenable quota on the subsequent remount RW. We 2198 * have to check 'flags' variable and not use sb_has_ 2199 * function because another quotaon / quotaoff could 2200 * change global state before we got here. We refuse 2201 * to suspend quotas when there is pending delete on 2202 * the quota file... */ 2203 if (!(flags & DQUOT_SUSPENDED)) 2204 iput(toputinode[cnt]); 2205 else if (!toputinode[cnt]->i_nlink) 2206 ret = -EBUSY; 2207 } 2208 return ret; 2209 } 2210 EXPORT_SYMBOL(dquot_disable); 2211 2212 int dquot_quota_off(struct super_block *sb, int type) 2213 { 2214 return dquot_disable(sb, type, 2215 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2216 } 2217 EXPORT_SYMBOL(dquot_quota_off); 2218 2219 /* 2220 * Turn quotas on on a device 2221 */ 2222 2223 /* 2224 * Helper function to turn quotas on when we already have the inode of 2225 * quota file and no quota information is loaded. 2226 */ 2227 static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 2228 unsigned int flags) 2229 { 2230 struct quota_format_type *fmt = find_quota_format(format_id); 2231 struct super_block *sb = inode->i_sb; 2232 struct quota_info *dqopt = sb_dqopt(sb); 2233 int error; 2234 int oldflags = -1; 2235 2236 if (!fmt) 2237 return -ESRCH; 2238 if (!S_ISREG(inode->i_mode)) { 2239 error = -EACCES; 2240 goto out_fmt; 2241 } 2242 if (IS_RDONLY(inode)) { 2243 error = -EROFS; 2244 goto out_fmt; 2245 } 2246 if (!sb->s_op->quota_write || !sb->s_op->quota_read || 2247 (type == PRJQUOTA && sb->dq_op->get_projid == NULL)) { 2248 error = -EINVAL; 2249 goto out_fmt; 2250 } 2251 /* Usage always has to be set... */ 2252 if (!(flags & DQUOT_USAGE_ENABLED)) { 2253 error = -EINVAL; 2254 goto out_fmt; 2255 } 2256 2257 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2258 /* As we bypass the pagecache we must now flush all the 2259 * dirty data and invalidate caches so that kernel sees 2260 * changes from userspace. It is not enough to just flush 2261 * the quota file since if blocksize < pagesize, invalidation 2262 * of the cache could fail because of other unrelated dirty 2263 * data */ 2264 sync_filesystem(sb); 2265 invalidate_bdev(sb->s_bdev); 2266 } 2267 mutex_lock(&dqopt->dqonoff_mutex); 2268 if (sb_has_quota_loaded(sb, type)) { 2269 error = -EBUSY; 2270 goto out_lock; 2271 } 2272 2273 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2274 /* We don't want quota and atime on quota files (deadlocks 2275 * possible) Also nobody should write to the file - we use 2276 * special IO operations which ignore the immutable bit. */ 2277 inode_lock(inode); 2278 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2279 S_NOQUOTA); 2280 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2281 inode_unlock(inode); 2282 /* 2283 * When S_NOQUOTA is set, remove dquot references as no more 2284 * references can be added 2285 */ 2286 __dquot_drop(inode); 2287 } 2288 2289 error = -EIO; 2290 dqopt->files[type] = igrab(inode); 2291 if (!dqopt->files[type]) 2292 goto out_lock; 2293 error = -EINVAL; 2294 if (!fmt->qf_ops->check_quota_file(sb, type)) 2295 goto out_file_init; 2296 2297 dqopt->ops[type] = fmt->qf_ops; 2298 dqopt->info[type].dqi_format = fmt; 2299 dqopt->info[type].dqi_fmt_id = format_id; 2300 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2301 mutex_lock(&dqopt->dqio_mutex); 2302 error = dqopt->ops[type]->read_file_info(sb, type); 2303 if (error < 0) { 2304 mutex_unlock(&dqopt->dqio_mutex); 2305 goto out_file_init; 2306 } 2307 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2308 dqopt->info[type].dqi_flags |= DQF_SYS_FILE; 2309 mutex_unlock(&dqopt->dqio_mutex); 2310 spin_lock(&dq_state_lock); 2311 dqopt->flags |= dquot_state_flag(flags, type); 2312 spin_unlock(&dq_state_lock); 2313 2314 add_dquot_ref(sb, type); 2315 mutex_unlock(&dqopt->dqonoff_mutex); 2316 2317 return 0; 2318 2319 out_file_init: 2320 dqopt->files[type] = NULL; 2321 iput(inode); 2322 out_lock: 2323 if (oldflags != -1) { 2324 inode_lock(inode); 2325 /* Set the flags back (in the case of accidental quotaon() 2326 * on a wrong file we don't want to mess up the flags) */ 2327 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2328 inode->i_flags |= oldflags; 2329 inode_unlock(inode); 2330 } 2331 mutex_unlock(&dqopt->dqonoff_mutex); 2332 out_fmt: 2333 put_quota_format(fmt); 2334 2335 return error; 2336 } 2337 2338 /* Reenable quotas on remount RW */ 2339 int dquot_resume(struct super_block *sb, int type) 2340 { 2341 struct quota_info *dqopt = sb_dqopt(sb); 2342 struct inode *inode; 2343 int ret = 0, cnt; 2344 unsigned int flags; 2345 2346 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2347 if (type != -1 && cnt != type) 2348 continue; 2349 2350 mutex_lock(&dqopt->dqonoff_mutex); 2351 if (!sb_has_quota_suspended(sb, cnt)) { 2352 mutex_unlock(&dqopt->dqonoff_mutex); 2353 continue; 2354 } 2355 inode = dqopt->files[cnt]; 2356 dqopt->files[cnt] = NULL; 2357 spin_lock(&dq_state_lock); 2358 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2359 DQUOT_LIMITS_ENABLED, 2360 cnt); 2361 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt); 2362 spin_unlock(&dq_state_lock); 2363 mutex_unlock(&dqopt->dqonoff_mutex); 2364 2365 flags = dquot_generic_flag(flags, cnt); 2366 ret = vfs_load_quota_inode(inode, cnt, 2367 dqopt->info[cnt].dqi_fmt_id, flags); 2368 iput(inode); 2369 } 2370 2371 return ret; 2372 } 2373 EXPORT_SYMBOL(dquot_resume); 2374 2375 int dquot_quota_on(struct super_block *sb, int type, int format_id, 2376 struct path *path) 2377 { 2378 int error = security_quota_on(path->dentry); 2379 if (error) 2380 return error; 2381 /* Quota file not on the same filesystem? */ 2382 if (path->dentry->d_sb != sb) 2383 error = -EXDEV; 2384 else 2385 error = vfs_load_quota_inode(d_inode(path->dentry), type, 2386 format_id, DQUOT_USAGE_ENABLED | 2387 DQUOT_LIMITS_ENABLED); 2388 return error; 2389 } 2390 EXPORT_SYMBOL(dquot_quota_on); 2391 2392 /* 2393 * More powerful function for turning on quotas allowing setting 2394 * of individual quota flags 2395 */ 2396 int dquot_enable(struct inode *inode, int type, int format_id, 2397 unsigned int flags) 2398 { 2399 int ret = 0; 2400 struct super_block *sb = inode->i_sb; 2401 struct quota_info *dqopt = sb_dqopt(sb); 2402 2403 /* Just unsuspend quotas? */ 2404 BUG_ON(flags & DQUOT_SUSPENDED); 2405 2406 if (!flags) 2407 return 0; 2408 /* Just updating flags needed? */ 2409 if (sb_has_quota_loaded(sb, type)) { 2410 mutex_lock(&dqopt->dqonoff_mutex); 2411 /* Now do a reliable test... */ 2412 if (!sb_has_quota_loaded(sb, type)) { 2413 mutex_unlock(&dqopt->dqonoff_mutex); 2414 goto load_quota; 2415 } 2416 if (flags & DQUOT_USAGE_ENABLED && 2417 sb_has_quota_usage_enabled(sb, type)) { 2418 ret = -EBUSY; 2419 goto out_lock; 2420 } 2421 if (flags & DQUOT_LIMITS_ENABLED && 2422 sb_has_quota_limits_enabled(sb, type)) { 2423 ret = -EBUSY; 2424 goto out_lock; 2425 } 2426 spin_lock(&dq_state_lock); 2427 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2428 spin_unlock(&dq_state_lock); 2429 out_lock: 2430 mutex_unlock(&dqopt->dqonoff_mutex); 2431 return ret; 2432 } 2433 2434 load_quota: 2435 return vfs_load_quota_inode(inode, type, format_id, flags); 2436 } 2437 EXPORT_SYMBOL(dquot_enable); 2438 2439 /* 2440 * This function is used when filesystem needs to initialize quotas 2441 * during mount time. 2442 */ 2443 int dquot_quota_on_mount(struct super_block *sb, char *qf_name, 2444 int format_id, int type) 2445 { 2446 struct dentry *dentry; 2447 int error; 2448 2449 inode_lock(d_inode(sb->s_root)); 2450 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2451 inode_unlock(d_inode(sb->s_root)); 2452 if (IS_ERR(dentry)) 2453 return PTR_ERR(dentry); 2454 2455 if (d_really_is_negative(dentry)) { 2456 error = -ENOENT; 2457 goto out; 2458 } 2459 2460 error = security_quota_on(dentry); 2461 if (!error) 2462 error = vfs_load_quota_inode(d_inode(dentry), type, format_id, 2463 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2464 2465 out: 2466 dput(dentry); 2467 return error; 2468 } 2469 EXPORT_SYMBOL(dquot_quota_on_mount); 2470 2471 static int dquot_quota_enable(struct super_block *sb, unsigned int flags) 2472 { 2473 int ret; 2474 int type; 2475 struct quota_info *dqopt = sb_dqopt(sb); 2476 2477 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) 2478 return -ENOSYS; 2479 /* Accounting cannot be turned on while fs is mounted */ 2480 flags &= ~(FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT); 2481 if (!flags) 2482 return -EINVAL; 2483 for (type = 0; type < MAXQUOTAS; type++) { 2484 if (!(flags & qtype_enforce_flag(type))) 2485 continue; 2486 /* Can't enforce without accounting */ 2487 if (!sb_has_quota_usage_enabled(sb, type)) 2488 return -EINVAL; 2489 ret = dquot_enable(dqopt->files[type], type, 2490 dqopt->info[type].dqi_fmt_id, 2491 DQUOT_LIMITS_ENABLED); 2492 if (ret < 0) 2493 goto out_err; 2494 } 2495 return 0; 2496 out_err: 2497 /* Backout enforcement enablement we already did */ 2498 for (type--; type >= 0; type--) { 2499 if (flags & qtype_enforce_flag(type)) 2500 dquot_disable(sb, type, DQUOT_LIMITS_ENABLED); 2501 } 2502 /* Error code translation for better compatibility with XFS */ 2503 if (ret == -EBUSY) 2504 ret = -EEXIST; 2505 return ret; 2506 } 2507 2508 static int dquot_quota_disable(struct super_block *sb, unsigned int flags) 2509 { 2510 int ret; 2511 int type; 2512 struct quota_info *dqopt = sb_dqopt(sb); 2513 2514 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) 2515 return -ENOSYS; 2516 /* 2517 * We don't support turning off accounting via quotactl. In principle 2518 * quota infrastructure can do this but filesystems don't expect 2519 * userspace to be able to do it. 2520 */ 2521 if (flags & 2522 (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT)) 2523 return -EOPNOTSUPP; 2524 2525 /* Filter out limits not enabled */ 2526 for (type = 0; type < MAXQUOTAS; type++) 2527 if (!sb_has_quota_limits_enabled(sb, type)) 2528 flags &= ~qtype_enforce_flag(type); 2529 /* Nothing left? */ 2530 if (!flags) 2531 return -EEXIST; 2532 for (type = 0; type < MAXQUOTAS; type++) { 2533 if (flags & qtype_enforce_flag(type)) { 2534 ret = dquot_disable(sb, type, DQUOT_LIMITS_ENABLED); 2535 if (ret < 0) 2536 goto out_err; 2537 } 2538 } 2539 return 0; 2540 out_err: 2541 /* Backout enforcement disabling we already did */ 2542 for (type--; type >= 0; type--) { 2543 if (flags & qtype_enforce_flag(type)) 2544 dquot_enable(dqopt->files[type], type, 2545 dqopt->info[type].dqi_fmt_id, 2546 DQUOT_LIMITS_ENABLED); 2547 } 2548 return ret; 2549 } 2550 2551 /* Generic routine for getting common part of quota structure */ 2552 static void do_get_dqblk(struct dquot *dquot, struct qc_dqblk *di) 2553 { 2554 struct mem_dqblk *dm = &dquot->dq_dqb; 2555 2556 memset(di, 0, sizeof(*di)); 2557 spin_lock(&dq_data_lock); 2558 di->d_spc_hardlimit = dm->dqb_bhardlimit; 2559 di->d_spc_softlimit = dm->dqb_bsoftlimit; 2560 di->d_ino_hardlimit = dm->dqb_ihardlimit; 2561 di->d_ino_softlimit = dm->dqb_isoftlimit; 2562 di->d_space = dm->dqb_curspace + dm->dqb_rsvspace; 2563 di->d_ino_count = dm->dqb_curinodes; 2564 di->d_spc_timer = dm->dqb_btime; 2565 di->d_ino_timer = dm->dqb_itime; 2566 spin_unlock(&dq_data_lock); 2567 } 2568 2569 int dquot_get_dqblk(struct super_block *sb, struct kqid qid, 2570 struct qc_dqblk *di) 2571 { 2572 struct dquot *dquot; 2573 2574 dquot = dqget(sb, qid); 2575 if (IS_ERR(dquot)) 2576 return PTR_ERR(dquot); 2577 do_get_dqblk(dquot, di); 2578 dqput(dquot); 2579 2580 return 0; 2581 } 2582 EXPORT_SYMBOL(dquot_get_dqblk); 2583 2584 int dquot_get_next_dqblk(struct super_block *sb, struct kqid *qid, 2585 struct qc_dqblk *di) 2586 { 2587 struct dquot *dquot; 2588 int err; 2589 2590 if (!sb->dq_op->get_next_id) 2591 return -ENOSYS; 2592 err = sb->dq_op->get_next_id(sb, qid); 2593 if (err < 0) 2594 return err; 2595 dquot = dqget(sb, *qid); 2596 if (IS_ERR(dquot)) 2597 return PTR_ERR(dquot); 2598 do_get_dqblk(dquot, di); 2599 dqput(dquot); 2600 2601 return 0; 2602 } 2603 EXPORT_SYMBOL(dquot_get_next_dqblk); 2604 2605 #define VFS_QC_MASK \ 2606 (QC_SPACE | QC_SPC_SOFT | QC_SPC_HARD | \ 2607 QC_INO_COUNT | QC_INO_SOFT | QC_INO_HARD | \ 2608 QC_SPC_TIMER | QC_INO_TIMER) 2609 2610 /* Generic routine for setting common part of quota structure */ 2611 static int do_set_dqblk(struct dquot *dquot, struct qc_dqblk *di) 2612 { 2613 struct mem_dqblk *dm = &dquot->dq_dqb; 2614 int check_blim = 0, check_ilim = 0; 2615 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 2616 2617 if (di->d_fieldmask & ~VFS_QC_MASK) 2618 return -EINVAL; 2619 2620 if (((di->d_fieldmask & QC_SPC_SOFT) && 2621 di->d_spc_softlimit > dqi->dqi_max_spc_limit) || 2622 ((di->d_fieldmask & QC_SPC_HARD) && 2623 di->d_spc_hardlimit > dqi->dqi_max_spc_limit) || 2624 ((di->d_fieldmask & QC_INO_SOFT) && 2625 (di->d_ino_softlimit > dqi->dqi_max_ino_limit)) || 2626 ((di->d_fieldmask & QC_INO_HARD) && 2627 (di->d_ino_hardlimit > dqi->dqi_max_ino_limit))) 2628 return -ERANGE; 2629 2630 spin_lock(&dq_data_lock); 2631 if (di->d_fieldmask & QC_SPACE) { 2632 dm->dqb_curspace = di->d_space - dm->dqb_rsvspace; 2633 check_blim = 1; 2634 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2635 } 2636 2637 if (di->d_fieldmask & QC_SPC_SOFT) 2638 dm->dqb_bsoftlimit = di->d_spc_softlimit; 2639 if (di->d_fieldmask & QC_SPC_HARD) 2640 dm->dqb_bhardlimit = di->d_spc_hardlimit; 2641 if (di->d_fieldmask & (QC_SPC_SOFT | QC_SPC_HARD)) { 2642 check_blim = 1; 2643 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2644 } 2645 2646 if (di->d_fieldmask & QC_INO_COUNT) { 2647 dm->dqb_curinodes = di->d_ino_count; 2648 check_ilim = 1; 2649 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2650 } 2651 2652 if (di->d_fieldmask & QC_INO_SOFT) 2653 dm->dqb_isoftlimit = di->d_ino_softlimit; 2654 if (di->d_fieldmask & QC_INO_HARD) 2655 dm->dqb_ihardlimit = di->d_ino_hardlimit; 2656 if (di->d_fieldmask & (QC_INO_SOFT | QC_INO_HARD)) { 2657 check_ilim = 1; 2658 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2659 } 2660 2661 if (di->d_fieldmask & QC_SPC_TIMER) { 2662 dm->dqb_btime = di->d_spc_timer; 2663 check_blim = 1; 2664 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2665 } 2666 2667 if (di->d_fieldmask & QC_INO_TIMER) { 2668 dm->dqb_itime = di->d_ino_timer; 2669 check_ilim = 1; 2670 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2671 } 2672 2673 if (check_blim) { 2674 if (!dm->dqb_bsoftlimit || 2675 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2676 dm->dqb_btime = 0; 2677 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2678 } else if (!(di->d_fieldmask & QC_SPC_TIMER)) 2679 /* Set grace only if user hasn't provided his own... */ 2680 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2681 } 2682 if (check_ilim) { 2683 if (!dm->dqb_isoftlimit || 2684 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2685 dm->dqb_itime = 0; 2686 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2687 } else if (!(di->d_fieldmask & QC_INO_TIMER)) 2688 /* Set grace only if user hasn't provided his own... */ 2689 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2690 } 2691 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2692 dm->dqb_isoftlimit) 2693 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2694 else 2695 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2696 spin_unlock(&dq_data_lock); 2697 mark_dquot_dirty(dquot); 2698 2699 return 0; 2700 } 2701 2702 int dquot_set_dqblk(struct super_block *sb, struct kqid qid, 2703 struct qc_dqblk *di) 2704 { 2705 struct dquot *dquot; 2706 int rc; 2707 2708 dquot = dqget(sb, qid); 2709 if (IS_ERR(dquot)) { 2710 rc = PTR_ERR(dquot); 2711 goto out; 2712 } 2713 rc = do_set_dqblk(dquot, di); 2714 dqput(dquot); 2715 out: 2716 return rc; 2717 } 2718 EXPORT_SYMBOL(dquot_set_dqblk); 2719 2720 /* Generic routine for getting common part of quota file information */ 2721 int dquot_get_state(struct super_block *sb, struct qc_state *state) 2722 { 2723 struct mem_dqinfo *mi; 2724 struct qc_type_state *tstate; 2725 struct quota_info *dqopt = sb_dqopt(sb); 2726 int type; 2727 2728 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2729 memset(state, 0, sizeof(*state)); 2730 for (type = 0; type < MAXQUOTAS; type++) { 2731 if (!sb_has_quota_active(sb, type)) 2732 continue; 2733 tstate = state->s_state + type; 2734 mi = sb_dqopt(sb)->info + type; 2735 tstate->flags = QCI_ACCT_ENABLED; 2736 spin_lock(&dq_data_lock); 2737 if (mi->dqi_flags & DQF_SYS_FILE) 2738 tstate->flags |= QCI_SYSFILE; 2739 if (mi->dqi_flags & DQF_ROOT_SQUASH) 2740 tstate->flags |= QCI_ROOT_SQUASH; 2741 if (sb_has_quota_limits_enabled(sb, type)) 2742 tstate->flags |= QCI_LIMITS_ENFORCED; 2743 tstate->spc_timelimit = mi->dqi_bgrace; 2744 tstate->ino_timelimit = mi->dqi_igrace; 2745 tstate->ino = dqopt->files[type]->i_ino; 2746 tstate->blocks = dqopt->files[type]->i_blocks; 2747 tstate->nextents = 1; /* We don't know... */ 2748 spin_unlock(&dq_data_lock); 2749 } 2750 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2751 return 0; 2752 } 2753 EXPORT_SYMBOL(dquot_get_state); 2754 2755 /* Generic routine for setting common part of quota file information */ 2756 int dquot_set_dqinfo(struct super_block *sb, int type, struct qc_info *ii) 2757 { 2758 struct mem_dqinfo *mi; 2759 int err = 0; 2760 2761 if ((ii->i_fieldmask & QC_WARNS_MASK) || 2762 (ii->i_fieldmask & QC_RT_SPC_TIMER)) 2763 return -EINVAL; 2764 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2765 if (!sb_has_quota_active(sb, type)) { 2766 err = -ESRCH; 2767 goto out; 2768 } 2769 mi = sb_dqopt(sb)->info + type; 2770 if (ii->i_fieldmask & QC_FLAGS) { 2771 if ((ii->i_flags & QCI_ROOT_SQUASH && 2772 mi->dqi_format->qf_fmt_id != QFMT_VFS_OLD)) { 2773 err = -EINVAL; 2774 goto out; 2775 } 2776 } 2777 spin_lock(&dq_data_lock); 2778 if (ii->i_fieldmask & QC_SPC_TIMER) 2779 mi->dqi_bgrace = ii->i_spc_timelimit; 2780 if (ii->i_fieldmask & QC_INO_TIMER) 2781 mi->dqi_igrace = ii->i_ino_timelimit; 2782 if (ii->i_fieldmask & QC_FLAGS) { 2783 if (ii->i_flags & QCI_ROOT_SQUASH) 2784 mi->dqi_flags |= DQF_ROOT_SQUASH; 2785 else 2786 mi->dqi_flags &= ~DQF_ROOT_SQUASH; 2787 } 2788 spin_unlock(&dq_data_lock); 2789 mark_info_dirty(sb, type); 2790 /* Force write to disk */ 2791 sb->dq_op->write_info(sb, type); 2792 out: 2793 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2794 return err; 2795 } 2796 EXPORT_SYMBOL(dquot_set_dqinfo); 2797 2798 const struct quotactl_ops dquot_quotactl_ops = { 2799 .quota_on = dquot_quota_on, 2800 .quota_off = dquot_quota_off, 2801 .quota_sync = dquot_quota_sync, 2802 .get_state = dquot_get_state, 2803 .set_info = dquot_set_dqinfo, 2804 .get_dqblk = dquot_get_dqblk, 2805 .get_nextdqblk = dquot_get_next_dqblk, 2806 .set_dqblk = dquot_set_dqblk 2807 }; 2808 EXPORT_SYMBOL(dquot_quotactl_ops); 2809 2810 const struct quotactl_ops dquot_quotactl_sysfile_ops = { 2811 .quota_enable = dquot_quota_enable, 2812 .quota_disable = dquot_quota_disable, 2813 .quota_sync = dquot_quota_sync, 2814 .get_state = dquot_get_state, 2815 .set_info = dquot_set_dqinfo, 2816 .get_dqblk = dquot_get_dqblk, 2817 .get_nextdqblk = dquot_get_next_dqblk, 2818 .set_dqblk = dquot_set_dqblk 2819 }; 2820 EXPORT_SYMBOL(dquot_quotactl_sysfile_ops); 2821 2822 static int do_proc_dqstats(struct ctl_table *table, int write, 2823 void __user *buffer, size_t *lenp, loff_t *ppos) 2824 { 2825 unsigned int type = (int *)table->data - dqstats.stat; 2826 2827 /* Update global table */ 2828 dqstats.stat[type] = 2829 percpu_counter_sum_positive(&dqstats.counter[type]); 2830 return proc_dointvec(table, write, buffer, lenp, ppos); 2831 } 2832 2833 static struct ctl_table fs_dqstats_table[] = { 2834 { 2835 .procname = "lookups", 2836 .data = &dqstats.stat[DQST_LOOKUPS], 2837 .maxlen = sizeof(int), 2838 .mode = 0444, 2839 .proc_handler = do_proc_dqstats, 2840 }, 2841 { 2842 .procname = "drops", 2843 .data = &dqstats.stat[DQST_DROPS], 2844 .maxlen = sizeof(int), 2845 .mode = 0444, 2846 .proc_handler = do_proc_dqstats, 2847 }, 2848 { 2849 .procname = "reads", 2850 .data = &dqstats.stat[DQST_READS], 2851 .maxlen = sizeof(int), 2852 .mode = 0444, 2853 .proc_handler = do_proc_dqstats, 2854 }, 2855 { 2856 .procname = "writes", 2857 .data = &dqstats.stat[DQST_WRITES], 2858 .maxlen = sizeof(int), 2859 .mode = 0444, 2860 .proc_handler = do_proc_dqstats, 2861 }, 2862 { 2863 .procname = "cache_hits", 2864 .data = &dqstats.stat[DQST_CACHE_HITS], 2865 .maxlen = sizeof(int), 2866 .mode = 0444, 2867 .proc_handler = do_proc_dqstats, 2868 }, 2869 { 2870 .procname = "allocated_dquots", 2871 .data = &dqstats.stat[DQST_ALLOC_DQUOTS], 2872 .maxlen = sizeof(int), 2873 .mode = 0444, 2874 .proc_handler = do_proc_dqstats, 2875 }, 2876 { 2877 .procname = "free_dquots", 2878 .data = &dqstats.stat[DQST_FREE_DQUOTS], 2879 .maxlen = sizeof(int), 2880 .mode = 0444, 2881 .proc_handler = do_proc_dqstats, 2882 }, 2883 { 2884 .procname = "syncs", 2885 .data = &dqstats.stat[DQST_SYNCS], 2886 .maxlen = sizeof(int), 2887 .mode = 0444, 2888 .proc_handler = do_proc_dqstats, 2889 }, 2890 #ifdef CONFIG_PRINT_QUOTA_WARNING 2891 { 2892 .procname = "warnings", 2893 .data = &flag_print_warnings, 2894 .maxlen = sizeof(int), 2895 .mode = 0644, 2896 .proc_handler = proc_dointvec, 2897 }, 2898 #endif 2899 { }, 2900 }; 2901 2902 static struct ctl_table fs_table[] = { 2903 { 2904 .procname = "quota", 2905 .mode = 0555, 2906 .child = fs_dqstats_table, 2907 }, 2908 { }, 2909 }; 2910 2911 static struct ctl_table sys_table[] = { 2912 { 2913 .procname = "fs", 2914 .mode = 0555, 2915 .child = fs_table, 2916 }, 2917 { }, 2918 }; 2919 2920 static int __init dquot_init(void) 2921 { 2922 int i, ret; 2923 unsigned long nr_hash, order; 2924 2925 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2926 2927 register_sysctl_table(sys_table); 2928 2929 dquot_cachep = kmem_cache_create("dquot", 2930 sizeof(struct dquot), sizeof(unsigned long) * 4, 2931 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2932 SLAB_MEM_SPREAD|SLAB_PANIC), 2933 NULL); 2934 2935 order = 0; 2936 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2937 if (!dquot_hash) 2938 panic("Cannot create dquot hash table"); 2939 2940 for (i = 0; i < _DQST_DQSTAT_LAST; i++) { 2941 ret = percpu_counter_init(&dqstats.counter[i], 0, GFP_KERNEL); 2942 if (ret) 2943 panic("Cannot create dquot stat counters"); 2944 } 2945 2946 /* Find power-of-two hlist_heads which can fit into allocation */ 2947 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2948 dq_hash_bits = 0; 2949 do { 2950 dq_hash_bits++; 2951 } while (nr_hash >> dq_hash_bits); 2952 dq_hash_bits--; 2953 2954 nr_hash = 1UL << dq_hash_bits; 2955 dq_hash_mask = nr_hash - 1; 2956 for (i = 0; i < nr_hash; i++) 2957 INIT_HLIST_HEAD(dquot_hash + i); 2958 2959 pr_info("VFS: Dquot-cache hash table entries: %ld (order %ld," 2960 " %ld bytes)\n", nr_hash, order, (PAGE_SIZE << order)); 2961 2962 register_shrinker(&dqcache_shrinker); 2963 2964 return 0; 2965 } 2966 fs_initcall(dquot_init); 2967