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 void __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 mutex_lock(&dqopt->files[cnt]->i_mutex); 686 truncate_inode_pages(&dqopt->files[cnt]->i_data, 0); 687 mutex_unlock(&dqopt->files[cnt]->i_mutex); 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 = NULL, *empty = NULL; 836 837 if (!sb_has_quota_active(sb, qid.type)) 838 return NULL; 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 goto out; 846 } 847 spin_unlock(&dq_state_lock); 848 849 dquot = find_dquot(hashent, sb, qid); 850 if (!dquot) { 851 if (!empty) { 852 spin_unlock(&dq_list_lock); 853 empty = get_empty_dquot(sb, qid.type); 854 if (!empty) 855 schedule(); /* Try to wait for a moment... */ 856 goto we_slept; 857 } 858 dquot = empty; 859 empty = NULL; 860 dquot->dq_id = qid; 861 /* all dquots go on the inuse_list */ 862 put_inuse(dquot); 863 /* hash it first so it can be found */ 864 insert_dquot_hash(dquot); 865 spin_unlock(&dq_list_lock); 866 dqstats_inc(DQST_LOOKUPS); 867 } else { 868 if (!atomic_read(&dquot->dq_count)) 869 remove_free_dquot(dquot); 870 atomic_inc(&dquot->dq_count); 871 spin_unlock(&dq_list_lock); 872 dqstats_inc(DQST_CACHE_HITS); 873 dqstats_inc(DQST_LOOKUPS); 874 } 875 /* Wait for dq_lock - after this we know that either dquot_release() is 876 * already finished or it will be canceled due to dq_count > 1 test */ 877 wait_on_dquot(dquot); 878 /* Read the dquot / allocate space in quota file */ 879 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && 880 sb->dq_op->acquire_dquot(dquot) < 0) { 881 dqput(dquot); 882 dquot = NULL; 883 goto out; 884 } 885 #ifdef CONFIG_QUOTA_DEBUG 886 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ 887 #endif 888 out: 889 if (empty) 890 do_destroy_dquot(empty); 891 892 return dquot; 893 } 894 EXPORT_SYMBOL(dqget); 895 896 static inline struct dquot **i_dquot(struct inode *inode) 897 { 898 /* Temporary workaround until all filesystems are converted. */ 899 if (!inode->i_sb->s_op->get_dquots) 900 return inode->i_dquot; 901 return inode->i_sb->s_op->get_dquots(inode); 902 } 903 904 static int dqinit_needed(struct inode *inode, int type) 905 { 906 int cnt; 907 908 if (IS_NOQUOTA(inode)) 909 return 0; 910 if (type != -1) 911 return !i_dquot(inode)[type]; 912 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 913 if (!i_dquot(inode)[cnt]) 914 return 1; 915 return 0; 916 } 917 918 /* This routine is guarded by dqonoff_mutex mutex */ 919 static void add_dquot_ref(struct super_block *sb, int type) 920 { 921 struct inode *inode, *old_inode = NULL; 922 #ifdef CONFIG_QUOTA_DEBUG 923 int reserved = 0; 924 #endif 925 926 spin_lock(&inode_sb_list_lock); 927 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 928 spin_lock(&inode->i_lock); 929 if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || 930 !atomic_read(&inode->i_writecount) || 931 !dqinit_needed(inode, type)) { 932 spin_unlock(&inode->i_lock); 933 continue; 934 } 935 __iget(inode); 936 spin_unlock(&inode->i_lock); 937 spin_unlock(&inode_sb_list_lock); 938 939 #ifdef CONFIG_QUOTA_DEBUG 940 if (unlikely(inode_get_rsv_space(inode) > 0)) 941 reserved = 1; 942 #endif 943 iput(old_inode); 944 __dquot_initialize(inode, type); 945 946 /* 947 * We hold a reference to 'inode' so it couldn't have been 948 * removed from s_inodes list while we dropped the 949 * inode_sb_list_lock We cannot iput the inode now as we can be 950 * holding the last reference and we cannot iput it under 951 * inode_sb_list_lock. So we keep the reference and iput it 952 * later. 953 */ 954 old_inode = inode; 955 spin_lock(&inode_sb_list_lock); 956 } 957 spin_unlock(&inode_sb_list_lock); 958 iput(old_inode); 959 960 #ifdef CONFIG_QUOTA_DEBUG 961 if (reserved) { 962 quota_error(sb, "Writes happened before quota was turned on " 963 "thus quota information is probably inconsistent. " 964 "Please run quotacheck(8)"); 965 } 966 #endif 967 } 968 969 /* 970 * Remove references to dquots from inode and add dquot to list for freeing 971 * if we have the last reference to dquot 972 */ 973 static void remove_inode_dquot_ref(struct inode *inode, int type, 974 struct list_head *tofree_head) 975 { 976 struct dquot *dquot = i_dquot(inode)[type]; 977 978 i_dquot(inode)[type] = NULL; 979 if (!dquot) 980 return; 981 982 if (list_empty(&dquot->dq_free)) { 983 /* 984 * The inode still has reference to dquot so it can't be in the 985 * free list 986 */ 987 spin_lock(&dq_list_lock); 988 list_add(&dquot->dq_free, tofree_head); 989 spin_unlock(&dq_list_lock); 990 } else { 991 /* 992 * Dquot is already in a list to put so we won't drop the last 993 * reference here. 994 */ 995 dqput(dquot); 996 } 997 } 998 999 /* 1000 * Free list of dquots 1001 * Dquots are removed from inodes and no new references can be got so we are 1002 * the only ones holding reference 1003 */ 1004 static void put_dquot_list(struct list_head *tofree_head) 1005 { 1006 struct list_head *act_head; 1007 struct dquot *dquot; 1008 1009 act_head = tofree_head->next; 1010 while (act_head != tofree_head) { 1011 dquot = list_entry(act_head, struct dquot, dq_free); 1012 act_head = act_head->next; 1013 /* Remove dquot from the list so we won't have problems... */ 1014 list_del_init(&dquot->dq_free); 1015 dqput(dquot); 1016 } 1017 } 1018 1019 static void remove_dquot_ref(struct super_block *sb, int type, 1020 struct list_head *tofree_head) 1021 { 1022 struct inode *inode; 1023 int reserved = 0; 1024 1025 spin_lock(&inode_sb_list_lock); 1026 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 1027 /* 1028 * We have to scan also I_NEW inodes because they can already 1029 * have quota pointer initialized. Luckily, we need to touch 1030 * only quota pointers and these have separate locking 1031 * (dq_data_lock). 1032 */ 1033 spin_lock(&dq_data_lock); 1034 if (!IS_NOQUOTA(inode)) { 1035 if (unlikely(inode_get_rsv_space(inode) > 0)) 1036 reserved = 1; 1037 remove_inode_dquot_ref(inode, type, tofree_head); 1038 } 1039 spin_unlock(&dq_data_lock); 1040 } 1041 spin_unlock(&inode_sb_list_lock); 1042 #ifdef CONFIG_QUOTA_DEBUG 1043 if (reserved) { 1044 printk(KERN_WARNING "VFS (%s): Writes happened after quota" 1045 " was disabled thus quota information is probably " 1046 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 1047 } 1048 #endif 1049 } 1050 1051 /* Gather all references from inodes and drop them */ 1052 static void drop_dquot_ref(struct super_block *sb, int type) 1053 { 1054 LIST_HEAD(tofree_head); 1055 1056 if (sb->dq_op) { 1057 remove_dquot_ref(sb, type, &tofree_head); 1058 synchronize_srcu(&dquot_srcu); 1059 put_dquot_list(&tofree_head); 1060 } 1061 } 1062 1063 static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1064 { 1065 dquot->dq_dqb.dqb_curinodes += number; 1066 } 1067 1068 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1069 { 1070 dquot->dq_dqb.dqb_curspace += number; 1071 } 1072 1073 static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1074 { 1075 dquot->dq_dqb.dqb_rsvspace += number; 1076 } 1077 1078 /* 1079 * Claim reserved quota space 1080 */ 1081 static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1082 { 1083 if (dquot->dq_dqb.dqb_rsvspace < number) { 1084 WARN_ON_ONCE(1); 1085 number = dquot->dq_dqb.dqb_rsvspace; 1086 } 1087 dquot->dq_dqb.dqb_curspace += number; 1088 dquot->dq_dqb.dqb_rsvspace -= number; 1089 } 1090 1091 static void dquot_reclaim_reserved_space(struct dquot *dquot, qsize_t number) 1092 { 1093 if (WARN_ON_ONCE(dquot->dq_dqb.dqb_curspace < number)) 1094 number = dquot->dq_dqb.dqb_curspace; 1095 dquot->dq_dqb.dqb_rsvspace += number; 1096 dquot->dq_dqb.dqb_curspace -= number; 1097 } 1098 1099 static inline 1100 void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1101 { 1102 if (dquot->dq_dqb.dqb_rsvspace >= number) 1103 dquot->dq_dqb.dqb_rsvspace -= number; 1104 else { 1105 WARN_ON_ONCE(1); 1106 dquot->dq_dqb.dqb_rsvspace = 0; 1107 } 1108 } 1109 1110 static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1111 { 1112 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1113 dquot->dq_dqb.dqb_curinodes >= number) 1114 dquot->dq_dqb.dqb_curinodes -= number; 1115 else 1116 dquot->dq_dqb.dqb_curinodes = 0; 1117 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1118 dquot->dq_dqb.dqb_itime = (time_t) 0; 1119 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1120 } 1121 1122 static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1123 { 1124 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1125 dquot->dq_dqb.dqb_curspace >= number) 1126 dquot->dq_dqb.dqb_curspace -= number; 1127 else 1128 dquot->dq_dqb.dqb_curspace = 0; 1129 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1130 dquot->dq_dqb.dqb_btime = (time_t) 0; 1131 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1132 } 1133 1134 struct dquot_warn { 1135 struct super_block *w_sb; 1136 struct kqid w_dq_id; 1137 short w_type; 1138 }; 1139 1140 static int warning_issued(struct dquot *dquot, const int warntype) 1141 { 1142 int flag = (warntype == QUOTA_NL_BHARDWARN || 1143 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1144 ((warntype == QUOTA_NL_IHARDWARN || 1145 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1146 1147 if (!flag) 1148 return 0; 1149 return test_and_set_bit(flag, &dquot->dq_flags); 1150 } 1151 1152 #ifdef CONFIG_PRINT_QUOTA_WARNING 1153 static int flag_print_warnings = 1; 1154 1155 static int need_print_warning(struct dquot_warn *warn) 1156 { 1157 if (!flag_print_warnings) 1158 return 0; 1159 1160 switch (warn->w_dq_id.type) { 1161 case USRQUOTA: 1162 return uid_eq(current_fsuid(), warn->w_dq_id.uid); 1163 case GRPQUOTA: 1164 return in_group_p(warn->w_dq_id.gid); 1165 case PRJQUOTA: /* Never taken... Just make gcc happy */ 1166 return 0; 1167 } 1168 return 0; 1169 } 1170 1171 /* Print warning to user which exceeded quota */ 1172 static void print_warning(struct dquot_warn *warn) 1173 { 1174 char *msg = NULL; 1175 struct tty_struct *tty; 1176 int warntype = warn->w_type; 1177 1178 if (warntype == QUOTA_NL_IHARDBELOW || 1179 warntype == QUOTA_NL_ISOFTBELOW || 1180 warntype == QUOTA_NL_BHARDBELOW || 1181 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(warn)) 1182 return; 1183 1184 tty = get_current_tty(); 1185 if (!tty) 1186 return; 1187 tty_write_message(tty, warn->w_sb->s_id); 1188 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1189 tty_write_message(tty, ": warning, "); 1190 else 1191 tty_write_message(tty, ": write failed, "); 1192 tty_write_message(tty, quotatypes[warn->w_dq_id.type]); 1193 switch (warntype) { 1194 case QUOTA_NL_IHARDWARN: 1195 msg = " file limit reached.\r\n"; 1196 break; 1197 case QUOTA_NL_ISOFTLONGWARN: 1198 msg = " file quota exceeded too long.\r\n"; 1199 break; 1200 case QUOTA_NL_ISOFTWARN: 1201 msg = " file quota exceeded.\r\n"; 1202 break; 1203 case QUOTA_NL_BHARDWARN: 1204 msg = " block limit reached.\r\n"; 1205 break; 1206 case QUOTA_NL_BSOFTLONGWARN: 1207 msg = " block quota exceeded too long.\r\n"; 1208 break; 1209 case QUOTA_NL_BSOFTWARN: 1210 msg = " block quota exceeded.\r\n"; 1211 break; 1212 } 1213 tty_write_message(tty, msg); 1214 tty_kref_put(tty); 1215 } 1216 #endif 1217 1218 static void prepare_warning(struct dquot_warn *warn, struct dquot *dquot, 1219 int warntype) 1220 { 1221 if (warning_issued(dquot, warntype)) 1222 return; 1223 warn->w_type = warntype; 1224 warn->w_sb = dquot->dq_sb; 1225 warn->w_dq_id = dquot->dq_id; 1226 } 1227 1228 /* 1229 * Write warnings to the console and send warning messages over netlink. 1230 * 1231 * Note that this function can call into tty and networking code. 1232 */ 1233 static void flush_warnings(struct dquot_warn *warn) 1234 { 1235 int i; 1236 1237 for (i = 0; i < MAXQUOTAS; i++) { 1238 if (warn[i].w_type == QUOTA_NL_NOWARN) 1239 continue; 1240 #ifdef CONFIG_PRINT_QUOTA_WARNING 1241 print_warning(&warn[i]); 1242 #endif 1243 quota_send_warning(warn[i].w_dq_id, 1244 warn[i].w_sb->s_dev, warn[i].w_type); 1245 } 1246 } 1247 1248 static int ignore_hardlimit(struct dquot *dquot) 1249 { 1250 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 1251 1252 return capable(CAP_SYS_RESOURCE) && 1253 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1254 !(info->dqi_flags & V1_DQF_RSQUASH)); 1255 } 1256 1257 /* needs dq_data_lock */ 1258 static int check_idq(struct dquot *dquot, qsize_t inodes, 1259 struct dquot_warn *warn) 1260 { 1261 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1262 1263 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type) || 1264 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1265 return 0; 1266 1267 if (dquot->dq_dqb.dqb_ihardlimit && 1268 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1269 !ignore_hardlimit(dquot)) { 1270 prepare_warning(warn, dquot, QUOTA_NL_IHARDWARN); 1271 return -EDQUOT; 1272 } 1273 1274 if (dquot->dq_dqb.dqb_isoftlimit && 1275 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1276 dquot->dq_dqb.dqb_itime && 1277 get_seconds() >= dquot->dq_dqb.dqb_itime && 1278 !ignore_hardlimit(dquot)) { 1279 prepare_warning(warn, dquot, QUOTA_NL_ISOFTLONGWARN); 1280 return -EDQUOT; 1281 } 1282 1283 if (dquot->dq_dqb.dqb_isoftlimit && 1284 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1285 dquot->dq_dqb.dqb_itime == 0) { 1286 prepare_warning(warn, dquot, QUOTA_NL_ISOFTWARN); 1287 dquot->dq_dqb.dqb_itime = get_seconds() + 1288 sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type].dqi_igrace; 1289 } 1290 1291 return 0; 1292 } 1293 1294 /* needs dq_data_lock */ 1295 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, 1296 struct dquot_warn *warn) 1297 { 1298 qsize_t tspace; 1299 struct super_block *sb = dquot->dq_sb; 1300 1301 if (!sb_has_quota_limits_enabled(sb, dquot->dq_id.type) || 1302 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1303 return 0; 1304 1305 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1306 + space; 1307 1308 if (dquot->dq_dqb.dqb_bhardlimit && 1309 tspace > dquot->dq_dqb.dqb_bhardlimit && 1310 !ignore_hardlimit(dquot)) { 1311 if (!prealloc) 1312 prepare_warning(warn, dquot, QUOTA_NL_BHARDWARN); 1313 return -EDQUOT; 1314 } 1315 1316 if (dquot->dq_dqb.dqb_bsoftlimit && 1317 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1318 dquot->dq_dqb.dqb_btime && 1319 get_seconds() >= dquot->dq_dqb.dqb_btime && 1320 !ignore_hardlimit(dquot)) { 1321 if (!prealloc) 1322 prepare_warning(warn, dquot, QUOTA_NL_BSOFTLONGWARN); 1323 return -EDQUOT; 1324 } 1325 1326 if (dquot->dq_dqb.dqb_bsoftlimit && 1327 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1328 dquot->dq_dqb.dqb_btime == 0) { 1329 if (!prealloc) { 1330 prepare_warning(warn, dquot, QUOTA_NL_BSOFTWARN); 1331 dquot->dq_dqb.dqb_btime = get_seconds() + 1332 sb_dqopt(sb)->info[dquot->dq_id.type].dqi_bgrace; 1333 } 1334 else 1335 /* 1336 * We don't allow preallocation to exceed softlimit so exceeding will 1337 * be always printed 1338 */ 1339 return -EDQUOT; 1340 } 1341 1342 return 0; 1343 } 1344 1345 static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1346 { 1347 qsize_t newinodes; 1348 1349 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1350 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1351 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type)) 1352 return QUOTA_NL_NOWARN; 1353 1354 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1355 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1356 return QUOTA_NL_ISOFTBELOW; 1357 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1358 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1359 return QUOTA_NL_IHARDBELOW; 1360 return QUOTA_NL_NOWARN; 1361 } 1362 1363 static int info_bdq_free(struct dquot *dquot, qsize_t space) 1364 { 1365 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1366 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1367 return QUOTA_NL_NOWARN; 1368 1369 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1370 return QUOTA_NL_BSOFTBELOW; 1371 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1372 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1373 return QUOTA_NL_BHARDBELOW; 1374 return QUOTA_NL_NOWARN; 1375 } 1376 1377 static int dquot_active(const struct inode *inode) 1378 { 1379 struct super_block *sb = inode->i_sb; 1380 1381 if (IS_NOQUOTA(inode)) 1382 return 0; 1383 return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb); 1384 } 1385 1386 /* 1387 * Initialize quota pointers in inode 1388 * 1389 * It is better to call this function outside of any transaction as it 1390 * might need a lot of space in journal for dquot structure allocation. 1391 */ 1392 static void __dquot_initialize(struct inode *inode, int type) 1393 { 1394 int cnt, init_needed = 0; 1395 struct dquot *got[MAXQUOTAS]; 1396 struct super_block *sb = inode->i_sb; 1397 qsize_t rsv; 1398 1399 if (!dquot_active(inode)) 1400 return; 1401 1402 /* First get references to structures we might need. */ 1403 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1404 struct kqid qid; 1405 got[cnt] = NULL; 1406 if (type != -1 && cnt != type) 1407 continue; 1408 /* 1409 * The i_dquot should have been initialized in most cases, 1410 * we check it without locking here to avoid unnecessary 1411 * dqget()/dqput() calls. 1412 */ 1413 if (i_dquot(inode)[cnt]) 1414 continue; 1415 init_needed = 1; 1416 1417 switch (cnt) { 1418 case USRQUOTA: 1419 qid = make_kqid_uid(inode->i_uid); 1420 break; 1421 case GRPQUOTA: 1422 qid = make_kqid_gid(inode->i_gid); 1423 break; 1424 } 1425 got[cnt] = dqget(sb, qid); 1426 } 1427 1428 /* All required i_dquot has been initialized */ 1429 if (!init_needed) 1430 return; 1431 1432 spin_lock(&dq_data_lock); 1433 if (IS_NOQUOTA(inode)) 1434 goto out_err; 1435 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1436 if (type != -1 && cnt != type) 1437 continue; 1438 /* Avoid races with quotaoff() */ 1439 if (!sb_has_quota_active(sb, cnt)) 1440 continue; 1441 /* We could race with quotaon or dqget() could have failed */ 1442 if (!got[cnt]) 1443 continue; 1444 if (!i_dquot(inode)[cnt]) { 1445 i_dquot(inode)[cnt] = got[cnt]; 1446 got[cnt] = NULL; 1447 /* 1448 * Make quota reservation system happy if someone 1449 * did a write before quota was turned on 1450 */ 1451 rsv = inode_get_rsv_space(inode); 1452 if (unlikely(rsv)) 1453 dquot_resv_space(i_dquot(inode)[cnt], rsv); 1454 } 1455 } 1456 out_err: 1457 spin_unlock(&dq_data_lock); 1458 /* Drop unused references */ 1459 dqput_all(got); 1460 } 1461 1462 void dquot_initialize(struct inode *inode) 1463 { 1464 __dquot_initialize(inode, -1); 1465 } 1466 EXPORT_SYMBOL(dquot_initialize); 1467 1468 /* 1469 * Release all quotas referenced by inode. 1470 * 1471 * This function only be called on inode free or converting 1472 * a file to quota file, no other users for the i_dquot in 1473 * both cases, so we needn't call synchronize_srcu() after 1474 * clearing i_dquot. 1475 */ 1476 static void __dquot_drop(struct inode *inode) 1477 { 1478 int cnt; 1479 struct dquot *put[MAXQUOTAS]; 1480 1481 spin_lock(&dq_data_lock); 1482 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1483 put[cnt] = i_dquot(inode)[cnt]; 1484 i_dquot(inode)[cnt] = NULL; 1485 } 1486 spin_unlock(&dq_data_lock); 1487 dqput_all(put); 1488 } 1489 1490 void dquot_drop(struct inode *inode) 1491 { 1492 int cnt; 1493 1494 if (IS_NOQUOTA(inode)) 1495 return; 1496 1497 /* 1498 * Test before calling to rule out calls from proc and such 1499 * where we are not allowed to block. Note that this is 1500 * actually reliable test even without the lock - the caller 1501 * must assure that nobody can come after the DQUOT_DROP and 1502 * add quota pointers back anyway. 1503 */ 1504 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1505 if (i_dquot(inode)[cnt]) 1506 break; 1507 } 1508 1509 if (cnt < MAXQUOTAS) 1510 __dquot_drop(inode); 1511 } 1512 EXPORT_SYMBOL(dquot_drop); 1513 1514 /* 1515 * inode_reserved_space is managed internally by quota, and protected by 1516 * i_lock similar to i_blocks+i_bytes. 1517 */ 1518 static qsize_t *inode_reserved_space(struct inode * inode) 1519 { 1520 /* Filesystem must explicitly define it's own method in order to use 1521 * quota reservation interface */ 1522 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1523 return inode->i_sb->dq_op->get_reserved_space(inode); 1524 } 1525 1526 void inode_add_rsv_space(struct inode *inode, qsize_t number) 1527 { 1528 spin_lock(&inode->i_lock); 1529 *inode_reserved_space(inode) += number; 1530 spin_unlock(&inode->i_lock); 1531 } 1532 EXPORT_SYMBOL(inode_add_rsv_space); 1533 1534 void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1535 { 1536 spin_lock(&inode->i_lock); 1537 *inode_reserved_space(inode) -= number; 1538 __inode_add_bytes(inode, number); 1539 spin_unlock(&inode->i_lock); 1540 } 1541 EXPORT_SYMBOL(inode_claim_rsv_space); 1542 1543 void inode_reclaim_rsv_space(struct inode *inode, qsize_t number) 1544 { 1545 spin_lock(&inode->i_lock); 1546 *inode_reserved_space(inode) += number; 1547 __inode_sub_bytes(inode, number); 1548 spin_unlock(&inode->i_lock); 1549 } 1550 EXPORT_SYMBOL(inode_reclaim_rsv_space); 1551 1552 void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1553 { 1554 spin_lock(&inode->i_lock); 1555 *inode_reserved_space(inode) -= number; 1556 spin_unlock(&inode->i_lock); 1557 } 1558 EXPORT_SYMBOL(inode_sub_rsv_space); 1559 1560 static qsize_t inode_get_rsv_space(struct inode *inode) 1561 { 1562 qsize_t ret; 1563 1564 if (!inode->i_sb->dq_op->get_reserved_space) 1565 return 0; 1566 spin_lock(&inode->i_lock); 1567 ret = *inode_reserved_space(inode); 1568 spin_unlock(&inode->i_lock); 1569 return ret; 1570 } 1571 1572 static void inode_incr_space(struct inode *inode, qsize_t number, 1573 int reserve) 1574 { 1575 if (reserve) 1576 inode_add_rsv_space(inode, number); 1577 else 1578 inode_add_bytes(inode, number); 1579 } 1580 1581 static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1582 { 1583 if (reserve) 1584 inode_sub_rsv_space(inode, number); 1585 else 1586 inode_sub_bytes(inode, number); 1587 } 1588 1589 /* 1590 * This functions updates i_blocks+i_bytes fields and quota information 1591 * (together with appropriate checks). 1592 * 1593 * NOTE: We absolutely rely on the fact that caller dirties the inode 1594 * (usually helpers in quotaops.h care about this) and holds a handle for 1595 * the current transaction so that dquot write and inode write go into the 1596 * same transaction. 1597 */ 1598 1599 /* 1600 * This operation can block, but only after everything is updated 1601 */ 1602 int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags) 1603 { 1604 int cnt, ret = 0, index; 1605 struct dquot_warn warn[MAXQUOTAS]; 1606 struct dquot **dquots = i_dquot(inode); 1607 int reserve = flags & DQUOT_SPACE_RESERVE; 1608 1609 if (!dquot_active(inode)) { 1610 inode_incr_space(inode, number, reserve); 1611 goto out; 1612 } 1613 1614 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1615 warn[cnt].w_type = QUOTA_NL_NOWARN; 1616 1617 index = srcu_read_lock(&dquot_srcu); 1618 spin_lock(&dq_data_lock); 1619 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1620 if (!dquots[cnt]) 1621 continue; 1622 ret = check_bdq(dquots[cnt], number, 1623 !(flags & DQUOT_SPACE_WARN), &warn[cnt]); 1624 if (ret && !(flags & DQUOT_SPACE_NOFAIL)) { 1625 spin_unlock(&dq_data_lock); 1626 goto out_flush_warn; 1627 } 1628 } 1629 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1630 if (!dquots[cnt]) 1631 continue; 1632 if (reserve) 1633 dquot_resv_space(dquots[cnt], number); 1634 else 1635 dquot_incr_space(dquots[cnt], number); 1636 } 1637 inode_incr_space(inode, number, reserve); 1638 spin_unlock(&dq_data_lock); 1639 1640 if (reserve) 1641 goto out_flush_warn; 1642 mark_all_dquot_dirty(dquots); 1643 out_flush_warn: 1644 srcu_read_unlock(&dquot_srcu, index); 1645 flush_warnings(warn); 1646 out: 1647 return ret; 1648 } 1649 EXPORT_SYMBOL(__dquot_alloc_space); 1650 1651 /* 1652 * This operation can block, but only after everything is updated 1653 */ 1654 int dquot_alloc_inode(struct inode *inode) 1655 { 1656 int cnt, ret = 0, index; 1657 struct dquot_warn warn[MAXQUOTAS]; 1658 struct dquot * const *dquots = i_dquot(inode); 1659 1660 if (!dquot_active(inode)) 1661 return 0; 1662 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1663 warn[cnt].w_type = QUOTA_NL_NOWARN; 1664 1665 index = srcu_read_lock(&dquot_srcu); 1666 spin_lock(&dq_data_lock); 1667 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1668 if (!dquots[cnt]) 1669 continue; 1670 ret = check_idq(dquots[cnt], 1, &warn[cnt]); 1671 if (ret) 1672 goto warn_put_all; 1673 } 1674 1675 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1676 if (!dquots[cnt]) 1677 continue; 1678 dquot_incr_inodes(dquots[cnt], 1); 1679 } 1680 1681 warn_put_all: 1682 spin_unlock(&dq_data_lock); 1683 if (ret == 0) 1684 mark_all_dquot_dirty(dquots); 1685 srcu_read_unlock(&dquot_srcu, index); 1686 flush_warnings(warn); 1687 return ret; 1688 } 1689 EXPORT_SYMBOL(dquot_alloc_inode); 1690 1691 /* 1692 * Convert in-memory reserved quotas to real consumed quotas 1693 */ 1694 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1695 { 1696 int cnt, index; 1697 1698 if (!dquot_active(inode)) { 1699 inode_claim_rsv_space(inode, number); 1700 return 0; 1701 } 1702 1703 index = srcu_read_lock(&dquot_srcu); 1704 spin_lock(&dq_data_lock); 1705 /* Claim reserved quotas to allocated quotas */ 1706 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1707 if (i_dquot(inode)[cnt]) 1708 dquot_claim_reserved_space(i_dquot(inode)[cnt], 1709 number); 1710 } 1711 /* Update inode bytes */ 1712 inode_claim_rsv_space(inode, number); 1713 spin_unlock(&dq_data_lock); 1714 mark_all_dquot_dirty(i_dquot(inode)); 1715 srcu_read_unlock(&dquot_srcu, index); 1716 return 0; 1717 } 1718 EXPORT_SYMBOL(dquot_claim_space_nodirty); 1719 1720 /* 1721 * Convert allocated space back to in-memory reserved quotas 1722 */ 1723 void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number) 1724 { 1725 int cnt, index; 1726 1727 if (!dquot_active(inode)) { 1728 inode_reclaim_rsv_space(inode, number); 1729 return; 1730 } 1731 1732 index = srcu_read_lock(&dquot_srcu); 1733 spin_lock(&dq_data_lock); 1734 /* Claim reserved quotas to allocated quotas */ 1735 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1736 if (i_dquot(inode)[cnt]) 1737 dquot_reclaim_reserved_space(i_dquot(inode)[cnt], 1738 number); 1739 } 1740 /* Update inode bytes */ 1741 inode_reclaim_rsv_space(inode, number); 1742 spin_unlock(&dq_data_lock); 1743 mark_all_dquot_dirty(i_dquot(inode)); 1744 srcu_read_unlock(&dquot_srcu, index); 1745 return; 1746 } 1747 EXPORT_SYMBOL(dquot_reclaim_space_nodirty); 1748 1749 /* 1750 * This operation can block, but only after everything is updated 1751 */ 1752 void __dquot_free_space(struct inode *inode, qsize_t number, int flags) 1753 { 1754 unsigned int cnt; 1755 struct dquot_warn warn[MAXQUOTAS]; 1756 struct dquot **dquots = i_dquot(inode); 1757 int reserve = flags & DQUOT_SPACE_RESERVE, index; 1758 1759 if (!dquot_active(inode)) { 1760 inode_decr_space(inode, number, reserve); 1761 return; 1762 } 1763 1764 index = srcu_read_lock(&dquot_srcu); 1765 spin_lock(&dq_data_lock); 1766 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1767 int wtype; 1768 1769 warn[cnt].w_type = QUOTA_NL_NOWARN; 1770 if (!dquots[cnt]) 1771 continue; 1772 wtype = info_bdq_free(dquots[cnt], number); 1773 if (wtype != QUOTA_NL_NOWARN) 1774 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1775 if (reserve) 1776 dquot_free_reserved_space(dquots[cnt], number); 1777 else 1778 dquot_decr_space(dquots[cnt], number); 1779 } 1780 inode_decr_space(inode, number, reserve); 1781 spin_unlock(&dq_data_lock); 1782 1783 if (reserve) 1784 goto out_unlock; 1785 mark_all_dquot_dirty(dquots); 1786 out_unlock: 1787 srcu_read_unlock(&dquot_srcu, index); 1788 flush_warnings(warn); 1789 } 1790 EXPORT_SYMBOL(__dquot_free_space); 1791 1792 /* 1793 * This operation can block, but only after everything is updated 1794 */ 1795 void dquot_free_inode(struct inode *inode) 1796 { 1797 unsigned int cnt; 1798 struct dquot_warn warn[MAXQUOTAS]; 1799 struct dquot * const *dquots = i_dquot(inode); 1800 int index; 1801 1802 if (!dquot_active(inode)) 1803 return; 1804 1805 index = srcu_read_lock(&dquot_srcu); 1806 spin_lock(&dq_data_lock); 1807 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1808 int wtype; 1809 1810 warn[cnt].w_type = QUOTA_NL_NOWARN; 1811 if (!dquots[cnt]) 1812 continue; 1813 wtype = info_idq_free(dquots[cnt], 1); 1814 if (wtype != QUOTA_NL_NOWARN) 1815 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1816 dquot_decr_inodes(dquots[cnt], 1); 1817 } 1818 spin_unlock(&dq_data_lock); 1819 mark_all_dquot_dirty(dquots); 1820 srcu_read_unlock(&dquot_srcu, index); 1821 flush_warnings(warn); 1822 } 1823 EXPORT_SYMBOL(dquot_free_inode); 1824 1825 /* 1826 * Transfer the number of inode and blocks from one diskquota to an other. 1827 * On success, dquot references in transfer_to are consumed and references 1828 * to original dquots that need to be released are placed there. On failure, 1829 * references are kept untouched. 1830 * 1831 * This operation can block, but only after everything is updated 1832 * A transaction must be started when entering this function. 1833 * 1834 * We are holding reference on transfer_from & transfer_to, no need to 1835 * protect them by srcu_read_lock(). 1836 */ 1837 int __dquot_transfer(struct inode *inode, struct dquot **transfer_to) 1838 { 1839 qsize_t space, cur_space; 1840 qsize_t rsv_space = 0; 1841 struct dquot *transfer_from[MAXQUOTAS] = {}; 1842 int cnt, ret = 0; 1843 char is_valid[MAXQUOTAS] = {}; 1844 struct dquot_warn warn_to[MAXQUOTAS]; 1845 struct dquot_warn warn_from_inodes[MAXQUOTAS]; 1846 struct dquot_warn warn_from_space[MAXQUOTAS]; 1847 1848 if (IS_NOQUOTA(inode)) 1849 return 0; 1850 /* Initialize the arrays */ 1851 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1852 warn_to[cnt].w_type = QUOTA_NL_NOWARN; 1853 warn_from_inodes[cnt].w_type = QUOTA_NL_NOWARN; 1854 warn_from_space[cnt].w_type = QUOTA_NL_NOWARN; 1855 } 1856 1857 spin_lock(&dq_data_lock); 1858 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1859 spin_unlock(&dq_data_lock); 1860 return 0; 1861 } 1862 cur_space = inode_get_bytes(inode); 1863 rsv_space = inode_get_rsv_space(inode); 1864 space = cur_space + rsv_space; 1865 /* Build the transfer_from list and check the limits */ 1866 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1867 /* 1868 * Skip changes for same uid or gid or for turned off quota-type. 1869 */ 1870 if (!transfer_to[cnt]) 1871 continue; 1872 /* Avoid races with quotaoff() */ 1873 if (!sb_has_quota_active(inode->i_sb, cnt)) 1874 continue; 1875 is_valid[cnt] = 1; 1876 transfer_from[cnt] = i_dquot(inode)[cnt]; 1877 ret = check_idq(transfer_to[cnt], 1, &warn_to[cnt]); 1878 if (ret) 1879 goto over_quota; 1880 ret = check_bdq(transfer_to[cnt], space, 0, &warn_to[cnt]); 1881 if (ret) 1882 goto over_quota; 1883 } 1884 1885 /* 1886 * Finally perform the needed transfer from transfer_from to transfer_to 1887 */ 1888 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1889 if (!is_valid[cnt]) 1890 continue; 1891 /* Due to IO error we might not have transfer_from[] structure */ 1892 if (transfer_from[cnt]) { 1893 int wtype; 1894 wtype = info_idq_free(transfer_from[cnt], 1); 1895 if (wtype != QUOTA_NL_NOWARN) 1896 prepare_warning(&warn_from_inodes[cnt], 1897 transfer_from[cnt], wtype); 1898 wtype = info_bdq_free(transfer_from[cnt], space); 1899 if (wtype != QUOTA_NL_NOWARN) 1900 prepare_warning(&warn_from_space[cnt], 1901 transfer_from[cnt], wtype); 1902 dquot_decr_inodes(transfer_from[cnt], 1); 1903 dquot_decr_space(transfer_from[cnt], cur_space); 1904 dquot_free_reserved_space(transfer_from[cnt], 1905 rsv_space); 1906 } 1907 1908 dquot_incr_inodes(transfer_to[cnt], 1); 1909 dquot_incr_space(transfer_to[cnt], cur_space); 1910 dquot_resv_space(transfer_to[cnt], rsv_space); 1911 1912 i_dquot(inode)[cnt] = transfer_to[cnt]; 1913 } 1914 spin_unlock(&dq_data_lock); 1915 1916 mark_all_dquot_dirty(transfer_from); 1917 mark_all_dquot_dirty(transfer_to); 1918 flush_warnings(warn_to); 1919 flush_warnings(warn_from_inodes); 1920 flush_warnings(warn_from_space); 1921 /* Pass back references to put */ 1922 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1923 if (is_valid[cnt]) 1924 transfer_to[cnt] = transfer_from[cnt]; 1925 return 0; 1926 over_quota: 1927 spin_unlock(&dq_data_lock); 1928 flush_warnings(warn_to); 1929 return ret; 1930 } 1931 EXPORT_SYMBOL(__dquot_transfer); 1932 1933 /* Wrapper for transferring ownership of an inode for uid/gid only 1934 * Called from FSXXX_setattr() 1935 */ 1936 int dquot_transfer(struct inode *inode, struct iattr *iattr) 1937 { 1938 struct dquot *transfer_to[MAXQUOTAS] = {}; 1939 struct super_block *sb = inode->i_sb; 1940 int ret; 1941 1942 if (!dquot_active(inode)) 1943 return 0; 1944 1945 if (iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)) 1946 transfer_to[USRQUOTA] = dqget(sb, make_kqid_uid(iattr->ia_uid)); 1947 if (iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid)) 1948 transfer_to[GRPQUOTA] = dqget(sb, make_kqid_gid(iattr->ia_gid)); 1949 1950 ret = __dquot_transfer(inode, transfer_to); 1951 dqput_all(transfer_to); 1952 return ret; 1953 } 1954 EXPORT_SYMBOL(dquot_transfer); 1955 1956 /* 1957 * Write info of quota file to disk 1958 */ 1959 int dquot_commit_info(struct super_block *sb, int type) 1960 { 1961 int ret; 1962 struct quota_info *dqopt = sb_dqopt(sb); 1963 1964 mutex_lock(&dqopt->dqio_mutex); 1965 ret = dqopt->ops[type]->write_file_info(sb, type); 1966 mutex_unlock(&dqopt->dqio_mutex); 1967 return ret; 1968 } 1969 EXPORT_SYMBOL(dquot_commit_info); 1970 1971 /* 1972 * Definitions of diskquota operations. 1973 */ 1974 const struct dquot_operations dquot_operations = { 1975 .write_dquot = dquot_commit, 1976 .acquire_dquot = dquot_acquire, 1977 .release_dquot = dquot_release, 1978 .mark_dirty = dquot_mark_dquot_dirty, 1979 .write_info = dquot_commit_info, 1980 .alloc_dquot = dquot_alloc, 1981 .destroy_dquot = dquot_destroy, 1982 }; 1983 EXPORT_SYMBOL(dquot_operations); 1984 1985 /* 1986 * Generic helper for ->open on filesystems supporting disk quotas. 1987 */ 1988 int dquot_file_open(struct inode *inode, struct file *file) 1989 { 1990 int error; 1991 1992 error = generic_file_open(inode, file); 1993 if (!error && (file->f_mode & FMODE_WRITE)) 1994 dquot_initialize(inode); 1995 return error; 1996 } 1997 EXPORT_SYMBOL(dquot_file_open); 1998 1999 /* 2000 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 2001 */ 2002 int dquot_disable(struct super_block *sb, int type, unsigned int flags) 2003 { 2004 int cnt, ret = 0; 2005 struct quota_info *dqopt = sb_dqopt(sb); 2006 struct inode *toputinode[MAXQUOTAS]; 2007 2008 /* Cannot turn off usage accounting without turning off limits, or 2009 * suspend quotas and simultaneously turn quotas off. */ 2010 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 2011 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 2012 DQUOT_USAGE_ENABLED))) 2013 return -EINVAL; 2014 2015 /* We need to serialize quota_off() for device */ 2016 mutex_lock(&dqopt->dqonoff_mutex); 2017 2018 /* 2019 * Skip everything if there's nothing to do. We have to do this because 2020 * sometimes we are called when fill_super() failed and calling 2021 * sync_fs() in such cases does no good. 2022 */ 2023 if (!sb_any_quota_loaded(sb)) { 2024 mutex_unlock(&dqopt->dqonoff_mutex); 2025 return 0; 2026 } 2027 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2028 toputinode[cnt] = NULL; 2029 if (type != -1 && cnt != type) 2030 continue; 2031 if (!sb_has_quota_loaded(sb, cnt)) 2032 continue; 2033 2034 if (flags & DQUOT_SUSPENDED) { 2035 spin_lock(&dq_state_lock); 2036 dqopt->flags |= 2037 dquot_state_flag(DQUOT_SUSPENDED, cnt); 2038 spin_unlock(&dq_state_lock); 2039 } else { 2040 spin_lock(&dq_state_lock); 2041 dqopt->flags &= ~dquot_state_flag(flags, cnt); 2042 /* Turning off suspended quotas? */ 2043 if (!sb_has_quota_loaded(sb, cnt) && 2044 sb_has_quota_suspended(sb, cnt)) { 2045 dqopt->flags &= ~dquot_state_flag( 2046 DQUOT_SUSPENDED, cnt); 2047 spin_unlock(&dq_state_lock); 2048 iput(dqopt->files[cnt]); 2049 dqopt->files[cnt] = NULL; 2050 continue; 2051 } 2052 spin_unlock(&dq_state_lock); 2053 } 2054 2055 /* We still have to keep quota loaded? */ 2056 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 2057 continue; 2058 2059 /* Note: these are blocking operations */ 2060 drop_dquot_ref(sb, cnt); 2061 invalidate_dquots(sb, cnt); 2062 /* 2063 * Now all dquots should be invalidated, all writes done so we 2064 * should be only users of the info. No locks needed. 2065 */ 2066 if (info_dirty(&dqopt->info[cnt])) 2067 sb->dq_op->write_info(sb, cnt); 2068 if (dqopt->ops[cnt]->free_file_info) 2069 dqopt->ops[cnt]->free_file_info(sb, cnt); 2070 put_quota_format(dqopt->info[cnt].dqi_format); 2071 2072 toputinode[cnt] = dqopt->files[cnt]; 2073 if (!sb_has_quota_loaded(sb, cnt)) 2074 dqopt->files[cnt] = NULL; 2075 dqopt->info[cnt].dqi_flags = 0; 2076 dqopt->info[cnt].dqi_igrace = 0; 2077 dqopt->info[cnt].dqi_bgrace = 0; 2078 dqopt->ops[cnt] = NULL; 2079 } 2080 mutex_unlock(&dqopt->dqonoff_mutex); 2081 2082 /* Skip syncing and setting flags if quota files are hidden */ 2083 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2084 goto put_inodes; 2085 2086 /* Sync the superblock so that buffers with quota data are written to 2087 * disk (and so userspace sees correct data afterwards). */ 2088 if (sb->s_op->sync_fs) 2089 sb->s_op->sync_fs(sb, 1); 2090 sync_blockdev(sb->s_bdev); 2091 /* Now the quota files are just ordinary files and we can set the 2092 * inode flags back. Moreover we discard the pagecache so that 2093 * userspace sees the writes we did bypassing the pagecache. We 2094 * must also discard the blockdev buffers so that we see the 2095 * changes done by userspace on the next quotaon() */ 2096 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2097 if (toputinode[cnt]) { 2098 mutex_lock(&dqopt->dqonoff_mutex); 2099 /* If quota was reenabled in the meantime, we have 2100 * nothing to do */ 2101 if (!sb_has_quota_loaded(sb, cnt)) { 2102 mutex_lock(&toputinode[cnt]->i_mutex); 2103 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 2104 S_NOATIME | S_NOQUOTA); 2105 truncate_inode_pages(&toputinode[cnt]->i_data, 2106 0); 2107 mutex_unlock(&toputinode[cnt]->i_mutex); 2108 mark_inode_dirty_sync(toputinode[cnt]); 2109 } 2110 mutex_unlock(&dqopt->dqonoff_mutex); 2111 } 2112 if (sb->s_bdev) 2113 invalidate_bdev(sb->s_bdev); 2114 put_inodes: 2115 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2116 if (toputinode[cnt]) { 2117 /* On remount RO, we keep the inode pointer so that we 2118 * can reenable quota on the subsequent remount RW. We 2119 * have to check 'flags' variable and not use sb_has_ 2120 * function because another quotaon / quotaoff could 2121 * change global state before we got here. We refuse 2122 * to suspend quotas when there is pending delete on 2123 * the quota file... */ 2124 if (!(flags & DQUOT_SUSPENDED)) 2125 iput(toputinode[cnt]); 2126 else if (!toputinode[cnt]->i_nlink) 2127 ret = -EBUSY; 2128 } 2129 return ret; 2130 } 2131 EXPORT_SYMBOL(dquot_disable); 2132 2133 int dquot_quota_off(struct super_block *sb, int type) 2134 { 2135 return dquot_disable(sb, type, 2136 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2137 } 2138 EXPORT_SYMBOL(dquot_quota_off); 2139 2140 /* 2141 * Turn quotas on on a device 2142 */ 2143 2144 /* 2145 * Helper function to turn quotas on when we already have the inode of 2146 * quota file and no quota information is loaded. 2147 */ 2148 static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 2149 unsigned int flags) 2150 { 2151 struct quota_format_type *fmt = find_quota_format(format_id); 2152 struct super_block *sb = inode->i_sb; 2153 struct quota_info *dqopt = sb_dqopt(sb); 2154 int error; 2155 int oldflags = -1; 2156 2157 if (!fmt) 2158 return -ESRCH; 2159 if (!S_ISREG(inode->i_mode)) { 2160 error = -EACCES; 2161 goto out_fmt; 2162 } 2163 if (IS_RDONLY(inode)) { 2164 error = -EROFS; 2165 goto out_fmt; 2166 } 2167 if (!sb->s_op->quota_write || !sb->s_op->quota_read) { 2168 error = -EINVAL; 2169 goto out_fmt; 2170 } 2171 /* Usage always has to be set... */ 2172 if (!(flags & DQUOT_USAGE_ENABLED)) { 2173 error = -EINVAL; 2174 goto out_fmt; 2175 } 2176 2177 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2178 /* As we bypass the pagecache we must now flush all the 2179 * dirty data and invalidate caches so that kernel sees 2180 * changes from userspace. It is not enough to just flush 2181 * the quota file since if blocksize < pagesize, invalidation 2182 * of the cache could fail because of other unrelated dirty 2183 * data */ 2184 sync_filesystem(sb); 2185 invalidate_bdev(sb->s_bdev); 2186 } 2187 mutex_lock(&dqopt->dqonoff_mutex); 2188 if (sb_has_quota_loaded(sb, type)) { 2189 error = -EBUSY; 2190 goto out_lock; 2191 } 2192 2193 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2194 /* We don't want quota and atime on quota files (deadlocks 2195 * possible) Also nobody should write to the file - we use 2196 * special IO operations which ignore the immutable bit. */ 2197 mutex_lock(&inode->i_mutex); 2198 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2199 S_NOQUOTA); 2200 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2201 mutex_unlock(&inode->i_mutex); 2202 /* 2203 * When S_NOQUOTA is set, remove dquot references as no more 2204 * references can be added 2205 */ 2206 __dquot_drop(inode); 2207 } 2208 2209 error = -EIO; 2210 dqopt->files[type] = igrab(inode); 2211 if (!dqopt->files[type]) 2212 goto out_lock; 2213 error = -EINVAL; 2214 if (!fmt->qf_ops->check_quota_file(sb, type)) 2215 goto out_file_init; 2216 2217 dqopt->ops[type] = fmt->qf_ops; 2218 dqopt->info[type].dqi_format = fmt; 2219 dqopt->info[type].dqi_fmt_id = format_id; 2220 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2221 mutex_lock(&dqopt->dqio_mutex); 2222 error = dqopt->ops[type]->read_file_info(sb, type); 2223 if (error < 0) { 2224 mutex_unlock(&dqopt->dqio_mutex); 2225 goto out_file_init; 2226 } 2227 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2228 dqopt->info[type].dqi_flags |= DQF_SYS_FILE; 2229 mutex_unlock(&dqopt->dqio_mutex); 2230 spin_lock(&dq_state_lock); 2231 dqopt->flags |= dquot_state_flag(flags, type); 2232 spin_unlock(&dq_state_lock); 2233 2234 add_dquot_ref(sb, type); 2235 mutex_unlock(&dqopt->dqonoff_mutex); 2236 2237 return 0; 2238 2239 out_file_init: 2240 dqopt->files[type] = NULL; 2241 iput(inode); 2242 out_lock: 2243 if (oldflags != -1) { 2244 mutex_lock(&inode->i_mutex); 2245 /* Set the flags back (in the case of accidental quotaon() 2246 * on a wrong file we don't want to mess up the flags) */ 2247 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2248 inode->i_flags |= oldflags; 2249 mutex_unlock(&inode->i_mutex); 2250 } 2251 mutex_unlock(&dqopt->dqonoff_mutex); 2252 out_fmt: 2253 put_quota_format(fmt); 2254 2255 return error; 2256 } 2257 2258 /* Reenable quotas on remount RW */ 2259 int dquot_resume(struct super_block *sb, int type) 2260 { 2261 struct quota_info *dqopt = sb_dqopt(sb); 2262 struct inode *inode; 2263 int ret = 0, cnt; 2264 unsigned int flags; 2265 2266 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2267 if (type != -1 && cnt != type) 2268 continue; 2269 2270 mutex_lock(&dqopt->dqonoff_mutex); 2271 if (!sb_has_quota_suspended(sb, cnt)) { 2272 mutex_unlock(&dqopt->dqonoff_mutex); 2273 continue; 2274 } 2275 inode = dqopt->files[cnt]; 2276 dqopt->files[cnt] = NULL; 2277 spin_lock(&dq_state_lock); 2278 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2279 DQUOT_LIMITS_ENABLED, 2280 cnt); 2281 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt); 2282 spin_unlock(&dq_state_lock); 2283 mutex_unlock(&dqopt->dqonoff_mutex); 2284 2285 flags = dquot_generic_flag(flags, cnt); 2286 ret = vfs_load_quota_inode(inode, cnt, 2287 dqopt->info[cnt].dqi_fmt_id, flags); 2288 iput(inode); 2289 } 2290 2291 return ret; 2292 } 2293 EXPORT_SYMBOL(dquot_resume); 2294 2295 int dquot_quota_on(struct super_block *sb, int type, int format_id, 2296 struct path *path) 2297 { 2298 int error = security_quota_on(path->dentry); 2299 if (error) 2300 return error; 2301 /* Quota file not on the same filesystem? */ 2302 if (path->dentry->d_sb != sb) 2303 error = -EXDEV; 2304 else 2305 error = vfs_load_quota_inode(path->dentry->d_inode, type, 2306 format_id, DQUOT_USAGE_ENABLED | 2307 DQUOT_LIMITS_ENABLED); 2308 return error; 2309 } 2310 EXPORT_SYMBOL(dquot_quota_on); 2311 2312 /* 2313 * More powerful function for turning on quotas allowing setting 2314 * of individual quota flags 2315 */ 2316 int dquot_enable(struct inode *inode, int type, int format_id, 2317 unsigned int flags) 2318 { 2319 int ret = 0; 2320 struct super_block *sb = inode->i_sb; 2321 struct quota_info *dqopt = sb_dqopt(sb); 2322 2323 /* Just unsuspend quotas? */ 2324 BUG_ON(flags & DQUOT_SUSPENDED); 2325 2326 if (!flags) 2327 return 0; 2328 /* Just updating flags needed? */ 2329 if (sb_has_quota_loaded(sb, type)) { 2330 mutex_lock(&dqopt->dqonoff_mutex); 2331 /* Now do a reliable test... */ 2332 if (!sb_has_quota_loaded(sb, type)) { 2333 mutex_unlock(&dqopt->dqonoff_mutex); 2334 goto load_quota; 2335 } 2336 if (flags & DQUOT_USAGE_ENABLED && 2337 sb_has_quota_usage_enabled(sb, type)) { 2338 ret = -EBUSY; 2339 goto out_lock; 2340 } 2341 if (flags & DQUOT_LIMITS_ENABLED && 2342 sb_has_quota_limits_enabled(sb, type)) { 2343 ret = -EBUSY; 2344 goto out_lock; 2345 } 2346 spin_lock(&dq_state_lock); 2347 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2348 spin_unlock(&dq_state_lock); 2349 out_lock: 2350 mutex_unlock(&dqopt->dqonoff_mutex); 2351 return ret; 2352 } 2353 2354 load_quota: 2355 return vfs_load_quota_inode(inode, type, format_id, flags); 2356 } 2357 EXPORT_SYMBOL(dquot_enable); 2358 2359 /* 2360 * This function is used when filesystem needs to initialize quotas 2361 * during mount time. 2362 */ 2363 int dquot_quota_on_mount(struct super_block *sb, char *qf_name, 2364 int format_id, int type) 2365 { 2366 struct dentry *dentry; 2367 int error; 2368 2369 mutex_lock(&sb->s_root->d_inode->i_mutex); 2370 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2371 mutex_unlock(&sb->s_root->d_inode->i_mutex); 2372 if (IS_ERR(dentry)) 2373 return PTR_ERR(dentry); 2374 2375 if (!dentry->d_inode) { 2376 error = -ENOENT; 2377 goto out; 2378 } 2379 2380 error = security_quota_on(dentry); 2381 if (!error) 2382 error = vfs_load_quota_inode(dentry->d_inode, type, format_id, 2383 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2384 2385 out: 2386 dput(dentry); 2387 return error; 2388 } 2389 EXPORT_SYMBOL(dquot_quota_on_mount); 2390 2391 static inline qsize_t qbtos(qsize_t blocks) 2392 { 2393 return blocks << QIF_DQBLKSIZE_BITS; 2394 } 2395 2396 static inline qsize_t stoqb(qsize_t space) 2397 { 2398 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; 2399 } 2400 2401 /* Generic routine for getting common part of quota structure */ 2402 static void do_get_dqblk(struct dquot *dquot, struct fs_disk_quota *di) 2403 { 2404 struct mem_dqblk *dm = &dquot->dq_dqb; 2405 2406 memset(di, 0, sizeof(*di)); 2407 di->d_version = FS_DQUOT_VERSION; 2408 di->d_flags = dquot->dq_id.type == USRQUOTA ? 2409 FS_USER_QUOTA : FS_GROUP_QUOTA; 2410 di->d_id = from_kqid_munged(current_user_ns(), dquot->dq_id); 2411 2412 spin_lock(&dq_data_lock); 2413 di->d_blk_hardlimit = stoqb(dm->dqb_bhardlimit); 2414 di->d_blk_softlimit = stoqb(dm->dqb_bsoftlimit); 2415 di->d_ino_hardlimit = dm->dqb_ihardlimit; 2416 di->d_ino_softlimit = dm->dqb_isoftlimit; 2417 di->d_bcount = dm->dqb_curspace + dm->dqb_rsvspace; 2418 di->d_icount = dm->dqb_curinodes; 2419 di->d_btimer = dm->dqb_btime; 2420 di->d_itimer = dm->dqb_itime; 2421 spin_unlock(&dq_data_lock); 2422 } 2423 2424 int dquot_get_dqblk(struct super_block *sb, struct kqid qid, 2425 struct fs_disk_quota *di) 2426 { 2427 struct dquot *dquot; 2428 2429 dquot = dqget(sb, qid); 2430 if (!dquot) 2431 return -ESRCH; 2432 do_get_dqblk(dquot, di); 2433 dqput(dquot); 2434 2435 return 0; 2436 } 2437 EXPORT_SYMBOL(dquot_get_dqblk); 2438 2439 #define VFS_FS_DQ_MASK \ 2440 (FS_DQ_BCOUNT | FS_DQ_BSOFT | FS_DQ_BHARD | \ 2441 FS_DQ_ICOUNT | FS_DQ_ISOFT | FS_DQ_IHARD | \ 2442 FS_DQ_BTIMER | FS_DQ_ITIMER) 2443 2444 /* Generic routine for setting common part of quota structure */ 2445 static int do_set_dqblk(struct dquot *dquot, struct fs_disk_quota *di) 2446 { 2447 struct mem_dqblk *dm = &dquot->dq_dqb; 2448 int check_blim = 0, check_ilim = 0; 2449 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 2450 2451 if (di->d_fieldmask & ~VFS_FS_DQ_MASK) 2452 return -EINVAL; 2453 2454 if (((di->d_fieldmask & FS_DQ_BSOFT) && 2455 (di->d_blk_softlimit > dqi->dqi_maxblimit)) || 2456 ((di->d_fieldmask & FS_DQ_BHARD) && 2457 (di->d_blk_hardlimit > dqi->dqi_maxblimit)) || 2458 ((di->d_fieldmask & FS_DQ_ISOFT) && 2459 (di->d_ino_softlimit > dqi->dqi_maxilimit)) || 2460 ((di->d_fieldmask & FS_DQ_IHARD) && 2461 (di->d_ino_hardlimit > dqi->dqi_maxilimit))) 2462 return -ERANGE; 2463 2464 spin_lock(&dq_data_lock); 2465 if (di->d_fieldmask & FS_DQ_BCOUNT) { 2466 dm->dqb_curspace = di->d_bcount - dm->dqb_rsvspace; 2467 check_blim = 1; 2468 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2469 } 2470 2471 if (di->d_fieldmask & FS_DQ_BSOFT) 2472 dm->dqb_bsoftlimit = qbtos(di->d_blk_softlimit); 2473 if (di->d_fieldmask & FS_DQ_BHARD) 2474 dm->dqb_bhardlimit = qbtos(di->d_blk_hardlimit); 2475 if (di->d_fieldmask & (FS_DQ_BSOFT | FS_DQ_BHARD)) { 2476 check_blim = 1; 2477 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2478 } 2479 2480 if (di->d_fieldmask & FS_DQ_ICOUNT) { 2481 dm->dqb_curinodes = di->d_icount; 2482 check_ilim = 1; 2483 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2484 } 2485 2486 if (di->d_fieldmask & FS_DQ_ISOFT) 2487 dm->dqb_isoftlimit = di->d_ino_softlimit; 2488 if (di->d_fieldmask & FS_DQ_IHARD) 2489 dm->dqb_ihardlimit = di->d_ino_hardlimit; 2490 if (di->d_fieldmask & (FS_DQ_ISOFT | FS_DQ_IHARD)) { 2491 check_ilim = 1; 2492 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2493 } 2494 2495 if (di->d_fieldmask & FS_DQ_BTIMER) { 2496 dm->dqb_btime = di->d_btimer; 2497 check_blim = 1; 2498 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2499 } 2500 2501 if (di->d_fieldmask & FS_DQ_ITIMER) { 2502 dm->dqb_itime = di->d_itimer; 2503 check_ilim = 1; 2504 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2505 } 2506 2507 if (check_blim) { 2508 if (!dm->dqb_bsoftlimit || 2509 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2510 dm->dqb_btime = 0; 2511 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2512 } else if (!(di->d_fieldmask & FS_DQ_BTIMER)) 2513 /* Set grace only if user hasn't provided his own... */ 2514 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2515 } 2516 if (check_ilim) { 2517 if (!dm->dqb_isoftlimit || 2518 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2519 dm->dqb_itime = 0; 2520 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2521 } else if (!(di->d_fieldmask & FS_DQ_ITIMER)) 2522 /* Set grace only if user hasn't provided his own... */ 2523 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2524 } 2525 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2526 dm->dqb_isoftlimit) 2527 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2528 else 2529 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2530 spin_unlock(&dq_data_lock); 2531 mark_dquot_dirty(dquot); 2532 2533 return 0; 2534 } 2535 2536 int dquot_set_dqblk(struct super_block *sb, struct kqid qid, 2537 struct fs_disk_quota *di) 2538 { 2539 struct dquot *dquot; 2540 int rc; 2541 2542 dquot = dqget(sb, qid); 2543 if (!dquot) { 2544 rc = -ESRCH; 2545 goto out; 2546 } 2547 rc = do_set_dqblk(dquot, di); 2548 dqput(dquot); 2549 out: 2550 return rc; 2551 } 2552 EXPORT_SYMBOL(dquot_set_dqblk); 2553 2554 /* Generic routine for getting common part of quota file information */ 2555 int dquot_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2556 { 2557 struct mem_dqinfo *mi; 2558 2559 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2560 if (!sb_has_quota_active(sb, type)) { 2561 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2562 return -ESRCH; 2563 } 2564 mi = sb_dqopt(sb)->info + type; 2565 spin_lock(&dq_data_lock); 2566 ii->dqi_bgrace = mi->dqi_bgrace; 2567 ii->dqi_igrace = mi->dqi_igrace; 2568 ii->dqi_flags = mi->dqi_flags & DQF_GETINFO_MASK; 2569 ii->dqi_valid = IIF_ALL; 2570 spin_unlock(&dq_data_lock); 2571 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2572 return 0; 2573 } 2574 EXPORT_SYMBOL(dquot_get_dqinfo); 2575 2576 /* Generic routine for setting common part of quota file information */ 2577 int dquot_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2578 { 2579 struct mem_dqinfo *mi; 2580 int err = 0; 2581 2582 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2583 if (!sb_has_quota_active(sb, type)) { 2584 err = -ESRCH; 2585 goto out; 2586 } 2587 mi = sb_dqopt(sb)->info + type; 2588 spin_lock(&dq_data_lock); 2589 if (ii->dqi_valid & IIF_BGRACE) 2590 mi->dqi_bgrace = ii->dqi_bgrace; 2591 if (ii->dqi_valid & IIF_IGRACE) 2592 mi->dqi_igrace = ii->dqi_igrace; 2593 if (ii->dqi_valid & IIF_FLAGS) 2594 mi->dqi_flags = (mi->dqi_flags & ~DQF_SETINFO_MASK) | 2595 (ii->dqi_flags & DQF_SETINFO_MASK); 2596 spin_unlock(&dq_data_lock); 2597 mark_info_dirty(sb, type); 2598 /* Force write to disk */ 2599 sb->dq_op->write_info(sb, type); 2600 out: 2601 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2602 return err; 2603 } 2604 EXPORT_SYMBOL(dquot_set_dqinfo); 2605 2606 const struct quotactl_ops dquot_quotactl_ops = { 2607 .quota_on = dquot_quota_on, 2608 .quota_off = dquot_quota_off, 2609 .quota_sync = dquot_quota_sync, 2610 .get_info = dquot_get_dqinfo, 2611 .set_info = dquot_set_dqinfo, 2612 .get_dqblk = dquot_get_dqblk, 2613 .set_dqblk = dquot_set_dqblk 2614 }; 2615 EXPORT_SYMBOL(dquot_quotactl_ops); 2616 2617 static int do_proc_dqstats(struct ctl_table *table, int write, 2618 void __user *buffer, size_t *lenp, loff_t *ppos) 2619 { 2620 unsigned int type = (int *)table->data - dqstats.stat; 2621 2622 /* Update global table */ 2623 dqstats.stat[type] = 2624 percpu_counter_sum_positive(&dqstats.counter[type]); 2625 return proc_dointvec(table, write, buffer, lenp, ppos); 2626 } 2627 2628 static struct ctl_table fs_dqstats_table[] = { 2629 { 2630 .procname = "lookups", 2631 .data = &dqstats.stat[DQST_LOOKUPS], 2632 .maxlen = sizeof(int), 2633 .mode = 0444, 2634 .proc_handler = do_proc_dqstats, 2635 }, 2636 { 2637 .procname = "drops", 2638 .data = &dqstats.stat[DQST_DROPS], 2639 .maxlen = sizeof(int), 2640 .mode = 0444, 2641 .proc_handler = do_proc_dqstats, 2642 }, 2643 { 2644 .procname = "reads", 2645 .data = &dqstats.stat[DQST_READS], 2646 .maxlen = sizeof(int), 2647 .mode = 0444, 2648 .proc_handler = do_proc_dqstats, 2649 }, 2650 { 2651 .procname = "writes", 2652 .data = &dqstats.stat[DQST_WRITES], 2653 .maxlen = sizeof(int), 2654 .mode = 0444, 2655 .proc_handler = do_proc_dqstats, 2656 }, 2657 { 2658 .procname = "cache_hits", 2659 .data = &dqstats.stat[DQST_CACHE_HITS], 2660 .maxlen = sizeof(int), 2661 .mode = 0444, 2662 .proc_handler = do_proc_dqstats, 2663 }, 2664 { 2665 .procname = "allocated_dquots", 2666 .data = &dqstats.stat[DQST_ALLOC_DQUOTS], 2667 .maxlen = sizeof(int), 2668 .mode = 0444, 2669 .proc_handler = do_proc_dqstats, 2670 }, 2671 { 2672 .procname = "free_dquots", 2673 .data = &dqstats.stat[DQST_FREE_DQUOTS], 2674 .maxlen = sizeof(int), 2675 .mode = 0444, 2676 .proc_handler = do_proc_dqstats, 2677 }, 2678 { 2679 .procname = "syncs", 2680 .data = &dqstats.stat[DQST_SYNCS], 2681 .maxlen = sizeof(int), 2682 .mode = 0444, 2683 .proc_handler = do_proc_dqstats, 2684 }, 2685 #ifdef CONFIG_PRINT_QUOTA_WARNING 2686 { 2687 .procname = "warnings", 2688 .data = &flag_print_warnings, 2689 .maxlen = sizeof(int), 2690 .mode = 0644, 2691 .proc_handler = proc_dointvec, 2692 }, 2693 #endif 2694 { }, 2695 }; 2696 2697 static struct ctl_table fs_table[] = { 2698 { 2699 .procname = "quota", 2700 .mode = 0555, 2701 .child = fs_dqstats_table, 2702 }, 2703 { }, 2704 }; 2705 2706 static struct ctl_table sys_table[] = { 2707 { 2708 .procname = "fs", 2709 .mode = 0555, 2710 .child = fs_table, 2711 }, 2712 { }, 2713 }; 2714 2715 static int __init dquot_init(void) 2716 { 2717 int i, ret; 2718 unsigned long nr_hash, order; 2719 2720 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2721 2722 register_sysctl_table(sys_table); 2723 2724 dquot_cachep = kmem_cache_create("dquot", 2725 sizeof(struct dquot), sizeof(unsigned long) * 4, 2726 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2727 SLAB_MEM_SPREAD|SLAB_PANIC), 2728 NULL); 2729 2730 order = 0; 2731 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2732 if (!dquot_hash) 2733 panic("Cannot create dquot hash table"); 2734 2735 for (i = 0; i < _DQST_DQSTAT_LAST; i++) { 2736 ret = percpu_counter_init(&dqstats.counter[i], 0, GFP_KERNEL); 2737 if (ret) 2738 panic("Cannot create dquot stat counters"); 2739 } 2740 2741 /* Find power-of-two hlist_heads which can fit into allocation */ 2742 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2743 dq_hash_bits = 0; 2744 do { 2745 dq_hash_bits++; 2746 } while (nr_hash >> dq_hash_bits); 2747 dq_hash_bits--; 2748 2749 nr_hash = 1UL << dq_hash_bits; 2750 dq_hash_mask = nr_hash - 1; 2751 for (i = 0; i < nr_hash; i++) 2752 INIT_HLIST_HEAD(dquot_hash + i); 2753 2754 pr_info("VFS: Dquot-cache hash table entries: %ld (order %ld," 2755 " %ld bytes)\n", nr_hash, order, (PAGE_SIZE << order)); 2756 2757 register_shrinker(&dqcache_shrinker); 2758 2759 return 0; 2760 } 2761 module_init(dquot_init); 2762