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 126static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock); 127static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock); 128__cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock); 129EXPORT_SYMBOL(dq_data_lock); 130DEFINE_STATIC_SRCU(dquot_srcu); 131 132void __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} 150EXPORT_SYMBOL(__quota_error); 151 152#if defined(CONFIG_QUOTA_DEBUG) || defined(CONFIG_PRINT_QUOTA_WARNING) 153static char *quotatypes[] = INITQFNAMES; 154#endif 155static struct quota_format_type *quota_formats; /* List of registered formats */ 156static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES; 157 158/* SLAB cache for dquot structures */ 159static struct kmem_cache *dquot_cachep; 160 161int 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} 169EXPORT_SYMBOL(register_quota_format); 170 171void 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} 183EXPORT_SYMBOL(unregister_quota_format); 184 185static 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 216static 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 241static LIST_HEAD(inuse_list); 242static LIST_HEAD(free_dquots); 243static unsigned int dq_hash_bits, dq_hash_mask; 244static struct hlist_head *dquot_hash; 245 246struct dqstats dqstats; 247EXPORT_SYMBOL(dqstats); 248 249static qsize_t inode_get_rsv_space(struct inode *inode); 250static void __dquot_initialize(struct inode *inode, int type); 251 252static inline unsigned int 253hashfn(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 */ 266static 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 273static inline void remove_dquot_hash(struct dquot *dquot) 274{ 275 hlist_del_init(&dquot->dq_hash); 276} 277 278static 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 */ 293static 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 299static 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 307static 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 315static 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 324static void wait_on_dquot(struct dquot *dquot) 325{ 326 mutex_lock(&dquot->dq_lock); 327 mutex_unlock(&dquot->dq_lock); 328} 329 330static inline int dquot_dirty(struct dquot *dquot) 331{ 332 return test_bit(DQ_MOD_B, &dquot->dq_flags); 333} 334 335static 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 */ 341int 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} 358EXPORT_SYMBOL(dquot_mark_dquot_dirty); 359 360/* Dirtify all the dquots - this can block when journalling */ 361static 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 376static 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 */ 385static 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 393void 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} 397EXPORT_SYMBOL(mark_info_dirty); 398 399/* 400 * Read dquot from disk and alloc space for it 401 */ 402 403int 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); 431out_iolock: 432 mutex_unlock(&dqopt->dqio_mutex); 433 mutex_unlock(&dquot->dq_lock); 434 return ret; 435} 436EXPORT_SYMBOL(dquot_acquire); 437 438/* 439 * Write dquot to disk 440 */ 441int 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; 459out_sem: 460 mutex_unlock(&dqopt->dqio_mutex); 461 return ret; 462} 463EXPORT_SYMBOL(dquot_commit); 464 465/* 466 * Release dquot 467 */ 468int 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); 490out_dqlock: 491 mutex_unlock(&dquot->dq_lock); 492 return ret; 493} 494EXPORT_SYMBOL(dquot_release); 495 496void dquot_destroy(struct dquot *dquot) 497{ 498 kmem_cache_free(dquot_cachep, dquot); 499} 500EXPORT_SYMBOL(dquot_destroy); 501 502static 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 */ 513static void invalidate_dquots(struct super_block *sb, int type) 514{ 515 struct dquot *dquot, *tmp; 516 517restart: 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 */ 561int 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); 597out: 598 dqput(old_dquot); 599 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 600 return ret; 601} 602EXPORT_SYMBOL(dquot_scan_active); 603 604/* Write all dquot structures to quota files */ 605int 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} 653EXPORT_SYMBOL(dquot_writeback_dquots); 654 655/* Write all dquot structures to disk and make them visible from userspace */ 656int 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} 693EXPORT_SYMBOL(dquot_quota_sync); 694 695static unsigned long 696dqcache_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 718static unsigned long 719dqcache_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 725static 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 */ 734void 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); 749we_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} 795EXPORT_SYMBOL(dqput); 796 797struct dquot *dquot_alloc(struct super_block *sb, int type) 798{ 799 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); 800} 801EXPORT_SYMBOL(dquot_alloc); 802 803static 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 */ 832struct 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; 839we_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 888out: 889 if (empty) 890 do_destroy_dquot(empty); 891 892 return dquot; 893} 894EXPORT_SYMBOL(dqget); 895 896static int dqinit_needed(struct inode *inode, int type) 897{ 898 int cnt; 899 900 if (IS_NOQUOTA(inode)) 901 return 0; 902 if (type != -1) 903 return !inode->i_dquot[type]; 904 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 905 if (!inode->i_dquot[cnt]) 906 return 1; 907 return 0; 908} 909 910/* This routine is guarded by dqonoff_mutex mutex */ 911static void add_dquot_ref(struct super_block *sb, int type) 912{ 913 struct inode *inode, *old_inode = NULL; 914#ifdef CONFIG_QUOTA_DEBUG 915 int reserved = 0; 916#endif 917 918 spin_lock(&inode_sb_list_lock); 919 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 920 spin_lock(&inode->i_lock); 921 if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || 922 !atomic_read(&inode->i_writecount) || 923 !dqinit_needed(inode, type)) { 924 spin_unlock(&inode->i_lock); 925 continue; 926 } 927 __iget(inode); 928 spin_unlock(&inode->i_lock); 929 spin_unlock(&inode_sb_list_lock); 930 931#ifdef CONFIG_QUOTA_DEBUG 932 if (unlikely(inode_get_rsv_space(inode) > 0)) 933 reserved = 1; 934#endif 935 iput(old_inode); 936 __dquot_initialize(inode, type); 937 938 /* 939 * We hold a reference to 'inode' so it couldn't have been 940 * removed from s_inodes list while we dropped the 941 * inode_sb_list_lock We cannot iput the inode now as we can be 942 * holding the last reference and we cannot iput it under 943 * inode_sb_list_lock. So we keep the reference and iput it 944 * later. 945 */ 946 old_inode = inode; 947 spin_lock(&inode_sb_list_lock); 948 } 949 spin_unlock(&inode_sb_list_lock); 950 iput(old_inode); 951 952#ifdef CONFIG_QUOTA_DEBUG 953 if (reserved) { 954 quota_error(sb, "Writes happened before quota was turned on " 955 "thus quota information is probably inconsistent. " 956 "Please run quotacheck(8)"); 957 } 958#endif 959} 960 961/* 962 * Remove references to dquots from inode and add dquot to list for freeing 963 * if we have the last reference to dquot 964 */ 965static void remove_inode_dquot_ref(struct inode *inode, int type, 966 struct list_head *tofree_head) 967{ 968 struct dquot *dquot = inode->i_dquot[type]; 969 970 inode->i_dquot[type] = NULL; 971 if (!dquot) 972 return; 973 974 if (list_empty(&dquot->dq_free)) { 975 /* 976 * The inode still has reference to dquot so it can't be in the 977 * free list 978 */ 979 spin_lock(&dq_list_lock); 980 list_add(&dquot->dq_free, tofree_head); 981 spin_unlock(&dq_list_lock); 982 } else { 983 /* 984 * Dquot is already in a list to put so we won't drop the last 985 * reference here. 986 */ 987 dqput(dquot); 988 } 989} 990 991/* 992 * Free list of dquots 993 * Dquots are removed from inodes and no new references can be got so we are 994 * the only ones holding reference 995 */ 996static void put_dquot_list(struct list_head *tofree_head) 997{ 998 struct list_head *act_head; 999 struct dquot *dquot; 1000 1001 act_head = tofree_head->next; 1002 while (act_head != tofree_head) { 1003 dquot = list_entry(act_head, struct dquot, dq_free); 1004 act_head = act_head->next; 1005 /* Remove dquot from the list so we won't have problems... */ 1006 list_del_init(&dquot->dq_free); 1007 dqput(dquot); 1008 } 1009} 1010 1011static void remove_dquot_ref(struct super_block *sb, int type, 1012 struct list_head *tofree_head) 1013{ 1014 struct inode *inode; 1015 int reserved = 0; 1016 1017 spin_lock(&inode_sb_list_lock); 1018 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 1019 /* 1020 * We have to scan also I_NEW inodes because they can already 1021 * have quota pointer initialized. Luckily, we need to touch 1022 * only quota pointers and these have separate locking 1023 * (dq_data_lock). 1024 */ 1025 spin_lock(&dq_data_lock); 1026 if (!IS_NOQUOTA(inode)) { 1027 if (unlikely(inode_get_rsv_space(inode) > 0)) 1028 reserved = 1; 1029 remove_inode_dquot_ref(inode, type, tofree_head); 1030 } 1031 spin_unlock(&dq_data_lock); 1032 } 1033 spin_unlock(&inode_sb_list_lock); 1034#ifdef CONFIG_QUOTA_DEBUG 1035 if (reserved) { 1036 printk(KERN_WARNING "VFS (%s): Writes happened after quota" 1037 " was disabled thus quota information is probably " 1038 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 1039 } 1040#endif 1041} 1042 1043/* Gather all references from inodes and drop them */ 1044static void drop_dquot_ref(struct super_block *sb, int type) 1045{ 1046 LIST_HEAD(tofree_head); 1047 1048 if (sb->dq_op) { 1049 remove_dquot_ref(sb, type, &tofree_head); 1050 synchronize_srcu(&dquot_srcu); 1051 put_dquot_list(&tofree_head); 1052 } 1053} 1054 1055static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1056{ 1057 dquot->dq_dqb.dqb_curinodes += number; 1058} 1059 1060static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1061{ 1062 dquot->dq_dqb.dqb_curspace += number; 1063} 1064 1065static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1066{ 1067 dquot->dq_dqb.dqb_rsvspace += number; 1068} 1069 1070/* 1071 * Claim reserved quota space 1072 */ 1073static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1074{ 1075 if (dquot->dq_dqb.dqb_rsvspace < number) { 1076 WARN_ON_ONCE(1); 1077 number = dquot->dq_dqb.dqb_rsvspace; 1078 } 1079 dquot->dq_dqb.dqb_curspace += number; 1080 dquot->dq_dqb.dqb_rsvspace -= number; 1081} 1082 1083static void dquot_reclaim_reserved_space(struct dquot *dquot, qsize_t number) 1084{ 1085 if (WARN_ON_ONCE(dquot->dq_dqb.dqb_curspace < number)) 1086 number = dquot->dq_dqb.dqb_curspace; 1087 dquot->dq_dqb.dqb_rsvspace += number; 1088 dquot->dq_dqb.dqb_curspace -= number; 1089} 1090 1091static inline 1092void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1093{ 1094 if (dquot->dq_dqb.dqb_rsvspace >= number) 1095 dquot->dq_dqb.dqb_rsvspace -= number; 1096 else { 1097 WARN_ON_ONCE(1); 1098 dquot->dq_dqb.dqb_rsvspace = 0; 1099 } 1100} 1101 1102static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1103{ 1104 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1105 dquot->dq_dqb.dqb_curinodes >= number) 1106 dquot->dq_dqb.dqb_curinodes -= number; 1107 else 1108 dquot->dq_dqb.dqb_curinodes = 0; 1109 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1110 dquot->dq_dqb.dqb_itime = (time_t) 0; 1111 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1112} 1113 1114static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1115{ 1116 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1117 dquot->dq_dqb.dqb_curspace >= number) 1118 dquot->dq_dqb.dqb_curspace -= number; 1119 else 1120 dquot->dq_dqb.dqb_curspace = 0; 1121 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1122 dquot->dq_dqb.dqb_btime = (time_t) 0; 1123 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1124} 1125 1126struct dquot_warn { 1127 struct super_block *w_sb; 1128 struct kqid w_dq_id; 1129 short w_type; 1130}; 1131 1132static int warning_issued(struct dquot *dquot, const int warntype) 1133{ 1134 int flag = (warntype == QUOTA_NL_BHARDWARN || 1135 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1136 ((warntype == QUOTA_NL_IHARDWARN || 1137 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1138 1139 if (!flag) 1140 return 0; 1141 return test_and_set_bit(flag, &dquot->dq_flags); 1142} 1143 1144#ifdef CONFIG_PRINT_QUOTA_WARNING 1145static int flag_print_warnings = 1; 1146 1147static int need_print_warning(struct dquot_warn *warn) 1148{ 1149 if (!flag_print_warnings) 1150 return 0; 1151 1152 switch (warn->w_dq_id.type) { 1153 case USRQUOTA: 1154 return uid_eq(current_fsuid(), warn->w_dq_id.uid); 1155 case GRPQUOTA: 1156 return in_group_p(warn->w_dq_id.gid); 1157 case PRJQUOTA: /* Never taken... Just make gcc happy */ 1158 return 0; 1159 } 1160 return 0; 1161} 1162 1163/* Print warning to user which exceeded quota */ 1164static void print_warning(struct dquot_warn *warn) 1165{ 1166 char *msg = NULL; 1167 struct tty_struct *tty; 1168 int warntype = warn->w_type; 1169 1170 if (warntype == QUOTA_NL_IHARDBELOW || 1171 warntype == QUOTA_NL_ISOFTBELOW || 1172 warntype == QUOTA_NL_BHARDBELOW || 1173 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(warn)) 1174 return; 1175 1176 tty = get_current_tty(); 1177 if (!tty) 1178 return; 1179 tty_write_message(tty, warn->w_sb->s_id); 1180 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1181 tty_write_message(tty, ": warning, "); 1182 else 1183 tty_write_message(tty, ": write failed, "); 1184 tty_write_message(tty, quotatypes[warn->w_dq_id.type]); 1185 switch (warntype) { 1186 case QUOTA_NL_IHARDWARN: 1187 msg = " file limit reached.\r\n"; 1188 break; 1189 case QUOTA_NL_ISOFTLONGWARN: 1190 msg = " file quota exceeded too long.\r\n"; 1191 break; 1192 case QUOTA_NL_ISOFTWARN: 1193 msg = " file quota exceeded.\r\n"; 1194 break; 1195 case QUOTA_NL_BHARDWARN: 1196 msg = " block limit reached.\r\n"; 1197 break; 1198 case QUOTA_NL_BSOFTLONGWARN: 1199 msg = " block quota exceeded too long.\r\n"; 1200 break; 1201 case QUOTA_NL_BSOFTWARN: 1202 msg = " block quota exceeded.\r\n"; 1203 break; 1204 } 1205 tty_write_message(tty, msg); 1206 tty_kref_put(tty); 1207} 1208#endif 1209 1210static void prepare_warning(struct dquot_warn *warn, struct dquot *dquot, 1211 int warntype) 1212{ 1213 if (warning_issued(dquot, warntype)) 1214 return; 1215 warn->w_type = warntype; 1216 warn->w_sb = dquot->dq_sb; 1217 warn->w_dq_id = dquot->dq_id; 1218} 1219 1220/* 1221 * Write warnings to the console and send warning messages over netlink. 1222 * 1223 * Note that this function can call into tty and networking code. 1224 */ 1225static void flush_warnings(struct dquot_warn *warn) 1226{ 1227 int i; 1228 1229 for (i = 0; i < MAXQUOTAS; i++) { 1230 if (warn[i].w_type == QUOTA_NL_NOWARN) 1231 continue; 1232#ifdef CONFIG_PRINT_QUOTA_WARNING 1233 print_warning(&warn[i]); 1234#endif 1235 quota_send_warning(warn[i].w_dq_id, 1236 warn[i].w_sb->s_dev, warn[i].w_type); 1237 } 1238} 1239 1240static int ignore_hardlimit(struct dquot *dquot) 1241{ 1242 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 1243 1244 return capable(CAP_SYS_RESOURCE) && 1245 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1246 !(info->dqi_flags & V1_DQF_RSQUASH)); 1247} 1248 1249/* needs dq_data_lock */ 1250static int check_idq(struct dquot *dquot, qsize_t inodes, 1251 struct dquot_warn *warn) 1252{ 1253 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1254 1255 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type) || 1256 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1257 return 0; 1258 1259 if (dquot->dq_dqb.dqb_ihardlimit && 1260 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1261 !ignore_hardlimit(dquot)) { 1262 prepare_warning(warn, dquot, QUOTA_NL_IHARDWARN); 1263 return -EDQUOT; 1264 } 1265 1266 if (dquot->dq_dqb.dqb_isoftlimit && 1267 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1268 dquot->dq_dqb.dqb_itime && 1269 get_seconds() >= dquot->dq_dqb.dqb_itime && 1270 !ignore_hardlimit(dquot)) { 1271 prepare_warning(warn, dquot, QUOTA_NL_ISOFTLONGWARN); 1272 return -EDQUOT; 1273 } 1274 1275 if (dquot->dq_dqb.dqb_isoftlimit && 1276 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1277 dquot->dq_dqb.dqb_itime == 0) { 1278 prepare_warning(warn, dquot, QUOTA_NL_ISOFTWARN); 1279 dquot->dq_dqb.dqb_itime = get_seconds() + 1280 sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type].dqi_igrace; 1281 } 1282 1283 return 0; 1284} 1285 1286/* needs dq_data_lock */ 1287static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, 1288 struct dquot_warn *warn) 1289{ 1290 qsize_t tspace; 1291 struct super_block *sb = dquot->dq_sb; 1292 1293 if (!sb_has_quota_limits_enabled(sb, dquot->dq_id.type) || 1294 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1295 return 0; 1296 1297 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1298 + space; 1299 1300 if (dquot->dq_dqb.dqb_bhardlimit && 1301 tspace > dquot->dq_dqb.dqb_bhardlimit && 1302 !ignore_hardlimit(dquot)) { 1303 if (!prealloc) 1304 prepare_warning(warn, dquot, QUOTA_NL_BHARDWARN); 1305 return -EDQUOT; 1306 } 1307 1308 if (dquot->dq_dqb.dqb_bsoftlimit && 1309 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1310 dquot->dq_dqb.dqb_btime && 1311 get_seconds() >= dquot->dq_dqb.dqb_btime && 1312 !ignore_hardlimit(dquot)) { 1313 if (!prealloc) 1314 prepare_warning(warn, dquot, QUOTA_NL_BSOFTLONGWARN); 1315 return -EDQUOT; 1316 } 1317 1318 if (dquot->dq_dqb.dqb_bsoftlimit && 1319 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1320 dquot->dq_dqb.dqb_btime == 0) { 1321 if (!prealloc) { 1322 prepare_warning(warn, dquot, QUOTA_NL_BSOFTWARN); 1323 dquot->dq_dqb.dqb_btime = get_seconds() + 1324 sb_dqopt(sb)->info[dquot->dq_id.type].dqi_bgrace; 1325 } 1326 else 1327 /* 1328 * We don't allow preallocation to exceed softlimit so exceeding will 1329 * be always printed 1330 */ 1331 return -EDQUOT; 1332 } 1333 1334 return 0; 1335} 1336 1337static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1338{ 1339 qsize_t newinodes; 1340 1341 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1342 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1343 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type)) 1344 return QUOTA_NL_NOWARN; 1345 1346 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1347 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1348 return QUOTA_NL_ISOFTBELOW; 1349 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1350 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1351 return QUOTA_NL_IHARDBELOW; 1352 return QUOTA_NL_NOWARN; 1353} 1354 1355static int info_bdq_free(struct dquot *dquot, qsize_t space) 1356{ 1357 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1358 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1359 return QUOTA_NL_NOWARN; 1360 1361 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1362 return QUOTA_NL_BSOFTBELOW; 1363 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1364 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1365 return QUOTA_NL_BHARDBELOW; 1366 return QUOTA_NL_NOWARN; 1367} 1368 1369static int dquot_active(const struct inode *inode) 1370{ 1371 struct super_block *sb = inode->i_sb; 1372 1373 if (IS_NOQUOTA(inode)) 1374 return 0; 1375 return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb); 1376} 1377 1378/* 1379 * Initialize quota pointers in inode 1380 * 1381 * It is better to call this function outside of any transaction as it 1382 * might need a lot of space in journal for dquot structure allocation. 1383 */ 1384static void __dquot_initialize(struct inode *inode, int type) 1385{ 1386 int cnt, init_needed = 0; 1387 struct dquot *got[MAXQUOTAS]; 1388 struct super_block *sb = inode->i_sb; 1389 qsize_t rsv; 1390 1391 if (!dquot_active(inode)) 1392 return; 1393 1394 /* First get references to structures we might need. */ 1395 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1396 struct kqid qid; 1397 got[cnt] = NULL; 1398 if (type != -1 && cnt != type) 1399 continue; 1400 /* 1401 * The i_dquot should have been initialized in most cases, 1402 * we check it without locking here to avoid unnecessary 1403 * dqget()/dqput() calls. 1404 */ 1405 if (inode->i_dquot[cnt]) 1406 continue; 1407 init_needed = 1; 1408 1409 switch (cnt) { 1410 case USRQUOTA: 1411 qid = make_kqid_uid(inode->i_uid); 1412 break; 1413 case GRPQUOTA: 1414 qid = make_kqid_gid(inode->i_gid); 1415 break; 1416 } 1417 got[cnt] = dqget(sb, qid); 1418 } 1419 1420 /* All required i_dquot has been initialized */ 1421 if (!init_needed) 1422 return; 1423 1424 spin_lock(&dq_data_lock); 1425 if (IS_NOQUOTA(inode)) 1426 goto out_err; 1427 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1428 if (type != -1 && cnt != type) 1429 continue; 1430 /* Avoid races with quotaoff() */ 1431 if (!sb_has_quota_active(sb, cnt)) 1432 continue; 1433 /* We could race with quotaon or dqget() could have failed */ 1434 if (!got[cnt]) 1435 continue; 1436 if (!inode->i_dquot[cnt]) { 1437 inode->i_dquot[cnt] = got[cnt]; 1438 got[cnt] = NULL; 1439 /* 1440 * Make quota reservation system happy if someone 1441 * did a write before quota was turned on 1442 */ 1443 rsv = inode_get_rsv_space(inode); 1444 if (unlikely(rsv)) 1445 dquot_resv_space(inode->i_dquot[cnt], rsv); 1446 } 1447 } 1448out_err: 1449 spin_unlock(&dq_data_lock); 1450 /* Drop unused references */ 1451 dqput_all(got); 1452} 1453 1454void dquot_initialize(struct inode *inode) 1455{ 1456 __dquot_initialize(inode, -1); 1457} 1458EXPORT_SYMBOL(dquot_initialize); 1459 1460/* 1461 * Release all quotas referenced by inode. 1462 * 1463 * This function only be called on inode free or converting 1464 * a file to quota file, no other users for the i_dquot in 1465 * both cases, so we needn't call synchronize_srcu() after 1466 * clearing i_dquot. 1467 */ 1468static void __dquot_drop(struct inode *inode) 1469{ 1470 int cnt; 1471 struct dquot *put[MAXQUOTAS]; 1472 1473 spin_lock(&dq_data_lock); 1474 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1475 put[cnt] = inode->i_dquot[cnt]; 1476 inode->i_dquot[cnt] = NULL; 1477 } 1478 spin_unlock(&dq_data_lock); 1479 dqput_all(put); 1480} 1481 1482void dquot_drop(struct inode *inode) 1483{ 1484 int cnt; 1485 1486 if (IS_NOQUOTA(inode)) 1487 return; 1488 1489 /* 1490 * Test before calling to rule out calls from proc and such 1491 * where we are not allowed to block. Note that this is 1492 * actually reliable test even without the lock - the caller 1493 * must assure that nobody can come after the DQUOT_DROP and 1494 * add quota pointers back anyway. 1495 */ 1496 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1497 if (inode->i_dquot[cnt]) 1498 break; 1499 } 1500 1501 if (cnt < MAXQUOTAS) 1502 __dquot_drop(inode); 1503} 1504EXPORT_SYMBOL(dquot_drop); 1505 1506/* 1507 * inode_reserved_space is managed internally by quota, and protected by 1508 * i_lock similar to i_blocks+i_bytes. 1509 */ 1510static qsize_t *inode_reserved_space(struct inode * inode) 1511{ 1512 /* Filesystem must explicitly define it's own method in order to use 1513 * quota reservation interface */ 1514 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1515 return inode->i_sb->dq_op->get_reserved_space(inode); 1516} 1517 1518void inode_add_rsv_space(struct inode *inode, qsize_t number) 1519{ 1520 spin_lock(&inode->i_lock); 1521 *inode_reserved_space(inode) += number; 1522 spin_unlock(&inode->i_lock); 1523} 1524EXPORT_SYMBOL(inode_add_rsv_space); 1525 1526void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1527{ 1528 spin_lock(&inode->i_lock); 1529 *inode_reserved_space(inode) -= number; 1530 __inode_add_bytes(inode, number); 1531 spin_unlock(&inode->i_lock); 1532} 1533EXPORT_SYMBOL(inode_claim_rsv_space); 1534 1535void inode_reclaim_rsv_space(struct inode *inode, qsize_t number) 1536{ 1537 spin_lock(&inode->i_lock); 1538 *inode_reserved_space(inode) += number; 1539 __inode_sub_bytes(inode, number); 1540 spin_unlock(&inode->i_lock); 1541} 1542EXPORT_SYMBOL(inode_reclaim_rsv_space); 1543 1544void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1545{ 1546 spin_lock(&inode->i_lock); 1547 *inode_reserved_space(inode) -= number; 1548 spin_unlock(&inode->i_lock); 1549} 1550EXPORT_SYMBOL(inode_sub_rsv_space); 1551 1552static qsize_t inode_get_rsv_space(struct inode *inode) 1553{ 1554 qsize_t ret; 1555 1556 if (!inode->i_sb->dq_op->get_reserved_space) 1557 return 0; 1558 spin_lock(&inode->i_lock); 1559 ret = *inode_reserved_space(inode); 1560 spin_unlock(&inode->i_lock); 1561 return ret; 1562} 1563 1564static void inode_incr_space(struct inode *inode, qsize_t number, 1565 int reserve) 1566{ 1567 if (reserve) 1568 inode_add_rsv_space(inode, number); 1569 else 1570 inode_add_bytes(inode, number); 1571} 1572 1573static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1574{ 1575 if (reserve) 1576 inode_sub_rsv_space(inode, number); 1577 else 1578 inode_sub_bytes(inode, number); 1579} 1580 1581/* 1582 * This functions updates i_blocks+i_bytes fields and quota information 1583 * (together with appropriate checks). 1584 * 1585 * NOTE: We absolutely rely on the fact that caller dirties the inode 1586 * (usually helpers in quotaops.h care about this) and holds a handle for 1587 * the current transaction so that dquot write and inode write go into the 1588 * same transaction. 1589 */ 1590 1591/* 1592 * This operation can block, but only after everything is updated 1593 */ 1594int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags) 1595{ 1596 int cnt, ret = 0, index; 1597 struct dquot_warn warn[MAXQUOTAS]; 1598 struct dquot **dquots = inode->i_dquot; 1599 int reserve = flags & DQUOT_SPACE_RESERVE; 1600 1601 if (!dquot_active(inode)) { 1602 inode_incr_space(inode, number, reserve); 1603 goto out; 1604 } 1605 1606 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1607 warn[cnt].w_type = QUOTA_NL_NOWARN; 1608 1609 index = srcu_read_lock(&dquot_srcu); 1610 spin_lock(&dq_data_lock); 1611 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1612 if (!dquots[cnt]) 1613 continue; 1614 ret = check_bdq(dquots[cnt], number, 1615 !(flags & DQUOT_SPACE_WARN), &warn[cnt]); 1616 if (ret && !(flags & DQUOT_SPACE_NOFAIL)) { 1617 spin_unlock(&dq_data_lock); 1618 goto out_flush_warn; 1619 } 1620 } 1621 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1622 if (!dquots[cnt]) 1623 continue; 1624 if (reserve) 1625 dquot_resv_space(dquots[cnt], number); 1626 else 1627 dquot_incr_space(dquots[cnt], number); 1628 } 1629 inode_incr_space(inode, number, reserve); 1630 spin_unlock(&dq_data_lock); 1631 1632 if (reserve) 1633 goto out_flush_warn; 1634 mark_all_dquot_dirty(dquots); 1635out_flush_warn: 1636 srcu_read_unlock(&dquot_srcu, index); 1637 flush_warnings(warn); 1638out: 1639 return ret; 1640} 1641EXPORT_SYMBOL(__dquot_alloc_space); 1642 1643/* 1644 * This operation can block, but only after everything is updated 1645 */ 1646int dquot_alloc_inode(const struct inode *inode) 1647{ 1648 int cnt, ret = 0, index; 1649 struct dquot_warn warn[MAXQUOTAS]; 1650 struct dquot * const *dquots = inode->i_dquot; 1651 1652 if (!dquot_active(inode)) 1653 return 0; 1654 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1655 warn[cnt].w_type = QUOTA_NL_NOWARN; 1656 1657 index = srcu_read_lock(&dquot_srcu); 1658 spin_lock(&dq_data_lock); 1659 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1660 if (!dquots[cnt]) 1661 continue; 1662 ret = check_idq(dquots[cnt], 1, &warn[cnt]); 1663 if (ret) 1664 goto warn_put_all; 1665 } 1666 1667 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1668 if (!dquots[cnt]) 1669 continue; 1670 dquot_incr_inodes(dquots[cnt], 1); 1671 } 1672 1673warn_put_all: 1674 spin_unlock(&dq_data_lock); 1675 if (ret == 0) 1676 mark_all_dquot_dirty(dquots); 1677 srcu_read_unlock(&dquot_srcu, index); 1678 flush_warnings(warn); 1679 return ret; 1680} 1681EXPORT_SYMBOL(dquot_alloc_inode); 1682 1683/* 1684 * Convert in-memory reserved quotas to real consumed quotas 1685 */ 1686int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1687{ 1688 int cnt, index; 1689 1690 if (!dquot_active(inode)) { 1691 inode_claim_rsv_space(inode, number); 1692 return 0; 1693 } 1694 1695 index = srcu_read_lock(&dquot_srcu); 1696 spin_lock(&dq_data_lock); 1697 /* Claim reserved quotas to allocated quotas */ 1698 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1699 if (inode->i_dquot[cnt]) 1700 dquot_claim_reserved_space(inode->i_dquot[cnt], 1701 number); 1702 } 1703 /* Update inode bytes */ 1704 inode_claim_rsv_space(inode, number); 1705 spin_unlock(&dq_data_lock); 1706 mark_all_dquot_dirty(inode->i_dquot); 1707 srcu_read_unlock(&dquot_srcu, index); 1708 return 0; 1709} 1710EXPORT_SYMBOL(dquot_claim_space_nodirty); 1711 1712/* 1713 * Convert allocated space back to in-memory reserved quotas 1714 */ 1715void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number) 1716{ 1717 int cnt, index; 1718 1719 if (!dquot_active(inode)) { 1720 inode_reclaim_rsv_space(inode, number); 1721 return; 1722 } 1723 1724 index = srcu_read_lock(&dquot_srcu); 1725 spin_lock(&dq_data_lock); 1726 /* Claim reserved quotas to allocated quotas */ 1727 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1728 if (inode->i_dquot[cnt]) 1729 dquot_reclaim_reserved_space(inode->i_dquot[cnt], 1730 number); 1731 } 1732 /* Update inode bytes */ 1733 inode_reclaim_rsv_space(inode, number); 1734 spin_unlock(&dq_data_lock); 1735 mark_all_dquot_dirty(inode->i_dquot); 1736 srcu_read_unlock(&dquot_srcu, index); 1737 return; 1738} 1739EXPORT_SYMBOL(dquot_reclaim_space_nodirty); 1740 1741/* 1742 * This operation can block, but only after everything is updated 1743 */ 1744void __dquot_free_space(struct inode *inode, qsize_t number, int flags) 1745{ 1746 unsigned int cnt; 1747 struct dquot_warn warn[MAXQUOTAS]; 1748 struct dquot **dquots = inode->i_dquot; 1749 int reserve = flags & DQUOT_SPACE_RESERVE, index; 1750 1751 if (!dquot_active(inode)) { 1752 inode_decr_space(inode, number, reserve); 1753 return; 1754 } 1755 1756 index = srcu_read_lock(&dquot_srcu); 1757 spin_lock(&dq_data_lock); 1758 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1759 int wtype; 1760 1761 warn[cnt].w_type = QUOTA_NL_NOWARN; 1762 if (!dquots[cnt]) 1763 continue; 1764 wtype = info_bdq_free(dquots[cnt], number); 1765 if (wtype != QUOTA_NL_NOWARN) 1766 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1767 if (reserve) 1768 dquot_free_reserved_space(dquots[cnt], number); 1769 else 1770 dquot_decr_space(dquots[cnt], number); 1771 } 1772 inode_decr_space(inode, number, reserve); 1773 spin_unlock(&dq_data_lock); 1774 1775 if (reserve) 1776 goto out_unlock; 1777 mark_all_dquot_dirty(dquots); 1778out_unlock: 1779 srcu_read_unlock(&dquot_srcu, index); 1780 flush_warnings(warn); 1781} 1782EXPORT_SYMBOL(__dquot_free_space); 1783 1784/* 1785 * This operation can block, but only after everything is updated 1786 */ 1787void dquot_free_inode(const struct inode *inode) 1788{ 1789 unsigned int cnt; 1790 struct dquot_warn warn[MAXQUOTAS]; 1791 struct dquot * const *dquots = inode->i_dquot; 1792 int index; 1793 1794 if (!dquot_active(inode)) 1795 return; 1796 1797 index = srcu_read_lock(&dquot_srcu); 1798 spin_lock(&dq_data_lock); 1799 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1800 int wtype; 1801 1802 warn[cnt].w_type = QUOTA_NL_NOWARN; 1803 if (!dquots[cnt]) 1804 continue; 1805 wtype = info_idq_free(dquots[cnt], 1); 1806 if (wtype != QUOTA_NL_NOWARN) 1807 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1808 dquot_decr_inodes(dquots[cnt], 1); 1809 } 1810 spin_unlock(&dq_data_lock); 1811 mark_all_dquot_dirty(dquots); 1812 srcu_read_unlock(&dquot_srcu, index); 1813 flush_warnings(warn); 1814} 1815EXPORT_SYMBOL(dquot_free_inode); 1816 1817/* 1818 * Transfer the number of inode and blocks from one diskquota to an other. 1819 * On success, dquot references in transfer_to are consumed and references 1820 * to original dquots that need to be released are placed there. On failure, 1821 * references are kept untouched. 1822 * 1823 * This operation can block, but only after everything is updated 1824 * A transaction must be started when entering this function. 1825 * 1826 * We are holding reference on transfer_from & transfer_to, no need to 1827 * protect them by srcu_read_lock(). 1828 */ 1829int __dquot_transfer(struct inode *inode, struct dquot **transfer_to) 1830{ 1831 qsize_t space, cur_space; 1832 qsize_t rsv_space = 0; 1833 struct dquot *transfer_from[MAXQUOTAS] = {}; 1834 int cnt, ret = 0; 1835 char is_valid[MAXQUOTAS] = {}; 1836 struct dquot_warn warn_to[MAXQUOTAS]; 1837 struct dquot_warn warn_from_inodes[MAXQUOTAS]; 1838 struct dquot_warn warn_from_space[MAXQUOTAS]; 1839 1840 if (IS_NOQUOTA(inode)) 1841 return 0; 1842 /* Initialize the arrays */ 1843 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1844 warn_to[cnt].w_type = QUOTA_NL_NOWARN; 1845 warn_from_inodes[cnt].w_type = QUOTA_NL_NOWARN; 1846 warn_from_space[cnt].w_type = QUOTA_NL_NOWARN; 1847 } 1848 1849 spin_lock(&dq_data_lock); 1850 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1851 spin_unlock(&dq_data_lock); 1852 return 0; 1853 } 1854 cur_space = inode_get_bytes(inode); 1855 rsv_space = inode_get_rsv_space(inode); 1856 space = cur_space + rsv_space; 1857 /* Build the transfer_from list and check the limits */ 1858 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1859 /* 1860 * Skip changes for same uid or gid or for turned off quota-type. 1861 */ 1862 if (!transfer_to[cnt]) 1863 continue; 1864 /* Avoid races with quotaoff() */ 1865 if (!sb_has_quota_active(inode->i_sb, cnt)) 1866 continue; 1867 is_valid[cnt] = 1; 1868 transfer_from[cnt] = inode->i_dquot[cnt]; 1869 ret = check_idq(transfer_to[cnt], 1, &warn_to[cnt]); 1870 if (ret) 1871 goto over_quota; 1872 ret = check_bdq(transfer_to[cnt], space, 0, &warn_to[cnt]); 1873 if (ret) 1874 goto over_quota; 1875 } 1876 1877 /* 1878 * Finally perform the needed transfer from transfer_from to transfer_to 1879 */ 1880 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1881 if (!is_valid[cnt]) 1882 continue; 1883 /* Due to IO error we might not have transfer_from[] structure */ 1884 if (transfer_from[cnt]) { 1885 int wtype; 1886 wtype = info_idq_free(transfer_from[cnt], 1); 1887 if (wtype != QUOTA_NL_NOWARN) 1888 prepare_warning(&warn_from_inodes[cnt], 1889 transfer_from[cnt], wtype); 1890 wtype = info_bdq_free(transfer_from[cnt], space); 1891 if (wtype != QUOTA_NL_NOWARN) 1892 prepare_warning(&warn_from_space[cnt], 1893 transfer_from[cnt], wtype); 1894 dquot_decr_inodes(transfer_from[cnt], 1); 1895 dquot_decr_space(transfer_from[cnt], cur_space); 1896 dquot_free_reserved_space(transfer_from[cnt], 1897 rsv_space); 1898 } 1899 1900 dquot_incr_inodes(transfer_to[cnt], 1); 1901 dquot_incr_space(transfer_to[cnt], cur_space); 1902 dquot_resv_space(transfer_to[cnt], rsv_space); 1903 1904 inode->i_dquot[cnt] = transfer_to[cnt]; 1905 } 1906 spin_unlock(&dq_data_lock); 1907 1908 mark_all_dquot_dirty(transfer_from); 1909 mark_all_dquot_dirty(transfer_to); 1910 flush_warnings(warn_to); 1911 flush_warnings(warn_from_inodes); 1912 flush_warnings(warn_from_space); 1913 /* Pass back references to put */ 1914 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1915 if (is_valid[cnt]) 1916 transfer_to[cnt] = transfer_from[cnt]; 1917 return 0; 1918over_quota: 1919 spin_unlock(&dq_data_lock); 1920 flush_warnings(warn_to); 1921 return ret; 1922} 1923EXPORT_SYMBOL(__dquot_transfer); 1924 1925/* Wrapper for transferring ownership of an inode for uid/gid only 1926 * Called from FSXXX_setattr() 1927 */ 1928int dquot_transfer(struct inode *inode, struct iattr *iattr) 1929{ 1930 struct dquot *transfer_to[MAXQUOTAS] = {}; 1931 struct super_block *sb = inode->i_sb; 1932 int ret; 1933 1934 if (!dquot_active(inode)) 1935 return 0; 1936 1937 if (iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)) 1938 transfer_to[USRQUOTA] = dqget(sb, make_kqid_uid(iattr->ia_uid)); 1939 if (iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid)) 1940 transfer_to[GRPQUOTA] = dqget(sb, make_kqid_gid(iattr->ia_gid)); 1941 1942 ret = __dquot_transfer(inode, transfer_to); 1943 dqput_all(transfer_to); 1944 return ret; 1945} 1946EXPORT_SYMBOL(dquot_transfer); 1947 1948/* 1949 * Write info of quota file to disk 1950 */ 1951int dquot_commit_info(struct super_block *sb, int type) 1952{ 1953 int ret; 1954 struct quota_info *dqopt = sb_dqopt(sb); 1955 1956 mutex_lock(&dqopt->dqio_mutex); 1957 ret = dqopt->ops[type]->write_file_info(sb, type); 1958 mutex_unlock(&dqopt->dqio_mutex); 1959 return ret; 1960} 1961EXPORT_SYMBOL(dquot_commit_info); 1962 1963/* 1964 * Definitions of diskquota operations. 1965 */ 1966const struct dquot_operations dquot_operations = { 1967 .write_dquot = dquot_commit, 1968 .acquire_dquot = dquot_acquire, 1969 .release_dquot = dquot_release, 1970 .mark_dirty = dquot_mark_dquot_dirty, 1971 .write_info = dquot_commit_info, 1972 .alloc_dquot = dquot_alloc, 1973 .destroy_dquot = dquot_destroy, 1974}; 1975EXPORT_SYMBOL(dquot_operations); 1976 1977/* 1978 * Generic helper for ->open on filesystems supporting disk quotas. 1979 */ 1980int dquot_file_open(struct inode *inode, struct file *file) 1981{ 1982 int error; 1983 1984 error = generic_file_open(inode, file); 1985 if (!error && (file->f_mode & FMODE_WRITE)) 1986 dquot_initialize(inode); 1987 return error; 1988} 1989EXPORT_SYMBOL(dquot_file_open); 1990 1991/* 1992 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 1993 */ 1994int dquot_disable(struct super_block *sb, int type, unsigned int flags) 1995{ 1996 int cnt, ret = 0; 1997 struct quota_info *dqopt = sb_dqopt(sb); 1998 struct inode *toputinode[MAXQUOTAS]; 1999 2000 /* Cannot turn off usage accounting without turning off limits, or 2001 * suspend quotas and simultaneously turn quotas off. */ 2002 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 2003 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 2004 DQUOT_USAGE_ENABLED))) 2005 return -EINVAL; 2006 2007 /* We need to serialize quota_off() for device */ 2008 mutex_lock(&dqopt->dqonoff_mutex); 2009 2010 /* 2011 * Skip everything if there's nothing to do. We have to do this because 2012 * sometimes we are called when fill_super() failed and calling 2013 * sync_fs() in such cases does no good. 2014 */ 2015 if (!sb_any_quota_loaded(sb)) { 2016 mutex_unlock(&dqopt->dqonoff_mutex); 2017 return 0; 2018 } 2019 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2020 toputinode[cnt] = NULL; 2021 if (type != -1 && cnt != type) 2022 continue; 2023 if (!sb_has_quota_loaded(sb, cnt)) 2024 continue; 2025 2026 if (flags & DQUOT_SUSPENDED) { 2027 spin_lock(&dq_state_lock); 2028 dqopt->flags |= 2029 dquot_state_flag(DQUOT_SUSPENDED, cnt); 2030 spin_unlock(&dq_state_lock); 2031 } else { 2032 spin_lock(&dq_state_lock); 2033 dqopt->flags &= ~dquot_state_flag(flags, cnt); 2034 /* Turning off suspended quotas? */ 2035 if (!sb_has_quota_loaded(sb, cnt) && 2036 sb_has_quota_suspended(sb, cnt)) { 2037 dqopt->flags &= ~dquot_state_flag( 2038 DQUOT_SUSPENDED, cnt); 2039 spin_unlock(&dq_state_lock); 2040 iput(dqopt->files[cnt]); 2041 dqopt->files[cnt] = NULL; 2042 continue; 2043 } 2044 spin_unlock(&dq_state_lock); 2045 } 2046 2047 /* We still have to keep quota loaded? */ 2048 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 2049 continue; 2050 2051 /* Note: these are blocking operations */ 2052 drop_dquot_ref(sb, cnt); 2053 invalidate_dquots(sb, cnt); 2054 /* 2055 * Now all dquots should be invalidated, all writes done so we 2056 * should be only users of the info. No locks needed. 2057 */ 2058 if (info_dirty(&dqopt->info[cnt])) 2059 sb->dq_op->write_info(sb, cnt); 2060 if (dqopt->ops[cnt]->free_file_info) 2061 dqopt->ops[cnt]->free_file_info(sb, cnt); 2062 put_quota_format(dqopt->info[cnt].dqi_format); 2063 2064 toputinode[cnt] = dqopt->files[cnt]; 2065 if (!sb_has_quota_loaded(sb, cnt)) 2066 dqopt->files[cnt] = NULL; 2067 dqopt->info[cnt].dqi_flags = 0; 2068 dqopt->info[cnt].dqi_igrace = 0; 2069 dqopt->info[cnt].dqi_bgrace = 0; 2070 dqopt->ops[cnt] = NULL; 2071 } 2072 mutex_unlock(&dqopt->dqonoff_mutex); 2073 2074 /* Skip syncing and setting flags if quota files are hidden */ 2075 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2076 goto put_inodes; 2077 2078 /* Sync the superblock so that buffers with quota data are written to 2079 * disk (and so userspace sees correct data afterwards). */ 2080 if (sb->s_op->sync_fs) 2081 sb->s_op->sync_fs(sb, 1); 2082 sync_blockdev(sb->s_bdev); 2083 /* Now the quota files are just ordinary files and we can set the 2084 * inode flags back. Moreover we discard the pagecache so that 2085 * userspace sees the writes we did bypassing the pagecache. We 2086 * must also discard the blockdev buffers so that we see the 2087 * changes done by userspace on the next quotaon() */ 2088 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2089 if (toputinode[cnt]) { 2090 mutex_lock(&dqopt->dqonoff_mutex); 2091 /* If quota was reenabled in the meantime, we have 2092 * nothing to do */ 2093 if (!sb_has_quota_loaded(sb, cnt)) { 2094 mutex_lock(&toputinode[cnt]->i_mutex); 2095 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 2096 S_NOATIME | S_NOQUOTA); 2097 truncate_inode_pages(&toputinode[cnt]->i_data, 2098 0); 2099 mutex_unlock(&toputinode[cnt]->i_mutex); 2100 mark_inode_dirty_sync(toputinode[cnt]); 2101 } 2102 mutex_unlock(&dqopt->dqonoff_mutex); 2103 } 2104 if (sb->s_bdev) 2105 invalidate_bdev(sb->s_bdev); 2106put_inodes: 2107 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2108 if (toputinode[cnt]) { 2109 /* On remount RO, we keep the inode pointer so that we 2110 * can reenable quota on the subsequent remount RW. We 2111 * have to check 'flags' variable and not use sb_has_ 2112 * function because another quotaon / quotaoff could 2113 * change global state before we got here. We refuse 2114 * to suspend quotas when there is pending delete on 2115 * the quota file... */ 2116 if (!(flags & DQUOT_SUSPENDED)) 2117 iput(toputinode[cnt]); 2118 else if (!toputinode[cnt]->i_nlink) 2119 ret = -EBUSY; 2120 } 2121 return ret; 2122} 2123EXPORT_SYMBOL(dquot_disable); 2124 2125int dquot_quota_off(struct super_block *sb, int type) 2126{ 2127 return dquot_disable(sb, type, 2128 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2129} 2130EXPORT_SYMBOL(dquot_quota_off); 2131 2132/* 2133 * Turn quotas on on a device 2134 */ 2135 2136/* 2137 * Helper function to turn quotas on when we already have the inode of 2138 * quota file and no quota information is loaded. 2139 */ 2140static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 2141 unsigned int flags) 2142{ 2143 struct quota_format_type *fmt = find_quota_format(format_id); 2144 struct super_block *sb = inode->i_sb; 2145 struct quota_info *dqopt = sb_dqopt(sb); 2146 int error; 2147 int oldflags = -1; 2148 2149 if (!fmt) 2150 return -ESRCH; 2151 if (!S_ISREG(inode->i_mode)) { 2152 error = -EACCES; 2153 goto out_fmt; 2154 } 2155 if (IS_RDONLY(inode)) { 2156 error = -EROFS; 2157 goto out_fmt; 2158 } 2159 if (!sb->s_op->quota_write || !sb->s_op->quota_read) { 2160 error = -EINVAL; 2161 goto out_fmt; 2162 } 2163 /* Usage always has to be set... */ 2164 if (!(flags & DQUOT_USAGE_ENABLED)) { 2165 error = -EINVAL; 2166 goto out_fmt; 2167 } 2168 2169 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2170 /* As we bypass the pagecache we must now flush all the 2171 * dirty data and invalidate caches so that kernel sees 2172 * changes from userspace. It is not enough to just flush 2173 * the quota file since if blocksize < pagesize, invalidation 2174 * of the cache could fail because of other unrelated dirty 2175 * data */ 2176 sync_filesystem(sb); 2177 invalidate_bdev(sb->s_bdev); 2178 } 2179 mutex_lock(&dqopt->dqonoff_mutex); 2180 if (sb_has_quota_loaded(sb, type)) { 2181 error = -EBUSY; 2182 goto out_lock; 2183 } 2184 2185 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2186 /* We don't want quota and atime on quota files (deadlocks 2187 * possible) Also nobody should write to the file - we use 2188 * special IO operations which ignore the immutable bit. */ 2189 mutex_lock(&inode->i_mutex); 2190 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2191 S_NOQUOTA); 2192 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2193 mutex_unlock(&inode->i_mutex); 2194 /* 2195 * When S_NOQUOTA is set, remove dquot references as no more 2196 * references can be added 2197 */ 2198 __dquot_drop(inode); 2199 } 2200 2201 error = -EIO; 2202 dqopt->files[type] = igrab(inode); 2203 if (!dqopt->files[type]) 2204 goto out_lock; 2205 error = -EINVAL; 2206 if (!fmt->qf_ops->check_quota_file(sb, type)) 2207 goto out_file_init; 2208 2209 dqopt->ops[type] = fmt->qf_ops; 2210 dqopt->info[type].dqi_format = fmt; 2211 dqopt->info[type].dqi_fmt_id = format_id; 2212 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2213 mutex_lock(&dqopt->dqio_mutex); 2214 error = dqopt->ops[type]->read_file_info(sb, type); 2215 if (error < 0) { 2216 mutex_unlock(&dqopt->dqio_mutex); 2217 goto out_file_init; 2218 } 2219 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2220 dqopt->info[type].dqi_flags |= DQF_SYS_FILE; 2221 mutex_unlock(&dqopt->dqio_mutex); 2222 spin_lock(&dq_state_lock); 2223 dqopt->flags |= dquot_state_flag(flags, type); 2224 spin_unlock(&dq_state_lock); 2225 2226 add_dquot_ref(sb, type); 2227 mutex_unlock(&dqopt->dqonoff_mutex); 2228 2229 return 0; 2230 2231out_file_init: 2232 dqopt->files[type] = NULL; 2233 iput(inode); 2234out_lock: 2235 if (oldflags != -1) { 2236 mutex_lock(&inode->i_mutex); 2237 /* Set the flags back (in the case of accidental quotaon() 2238 * on a wrong file we don't want to mess up the flags) */ 2239 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2240 inode->i_flags |= oldflags; 2241 mutex_unlock(&inode->i_mutex); 2242 } 2243 mutex_unlock(&dqopt->dqonoff_mutex); 2244out_fmt: 2245 put_quota_format(fmt); 2246 2247 return error; 2248} 2249 2250/* Reenable quotas on remount RW */ 2251int dquot_resume(struct super_block *sb, int type) 2252{ 2253 struct quota_info *dqopt = sb_dqopt(sb); 2254 struct inode *inode; 2255 int ret = 0, cnt; 2256 unsigned int flags; 2257 2258 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2259 if (type != -1 && cnt != type) 2260 continue; 2261 2262 mutex_lock(&dqopt->dqonoff_mutex); 2263 if (!sb_has_quota_suspended(sb, cnt)) { 2264 mutex_unlock(&dqopt->dqonoff_mutex); 2265 continue; 2266 } 2267 inode = dqopt->files[cnt]; 2268 dqopt->files[cnt] = NULL; 2269 spin_lock(&dq_state_lock); 2270 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2271 DQUOT_LIMITS_ENABLED, 2272 cnt); 2273 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt); 2274 spin_unlock(&dq_state_lock); 2275 mutex_unlock(&dqopt->dqonoff_mutex); 2276 2277 flags = dquot_generic_flag(flags, cnt); 2278 ret = vfs_load_quota_inode(inode, cnt, 2279 dqopt->info[cnt].dqi_fmt_id, flags); 2280 iput(inode); 2281 } 2282 2283 return ret; 2284} 2285EXPORT_SYMBOL(dquot_resume); 2286 2287int dquot_quota_on(struct super_block *sb, int type, int format_id, 2288 struct path *path) 2289{ 2290 int error = security_quota_on(path->dentry); 2291 if (error) 2292 return error; 2293 /* Quota file not on the same filesystem? */ 2294 if (path->dentry->d_sb != sb) 2295 error = -EXDEV; 2296 else 2297 error = vfs_load_quota_inode(path->dentry->d_inode, type, 2298 format_id, DQUOT_USAGE_ENABLED | 2299 DQUOT_LIMITS_ENABLED); 2300 return error; 2301} 2302EXPORT_SYMBOL(dquot_quota_on); 2303 2304/* 2305 * More powerful function for turning on quotas allowing setting 2306 * of individual quota flags 2307 */ 2308int dquot_enable(struct inode *inode, int type, int format_id, 2309 unsigned int flags) 2310{ 2311 int ret = 0; 2312 struct super_block *sb = inode->i_sb; 2313 struct quota_info *dqopt = sb_dqopt(sb); 2314 2315 /* Just unsuspend quotas? */ 2316 BUG_ON(flags & DQUOT_SUSPENDED); 2317 2318 if (!flags) 2319 return 0; 2320 /* Just updating flags needed? */ 2321 if (sb_has_quota_loaded(sb, type)) { 2322 mutex_lock(&dqopt->dqonoff_mutex); 2323 /* Now do a reliable test... */ 2324 if (!sb_has_quota_loaded(sb, type)) { 2325 mutex_unlock(&dqopt->dqonoff_mutex); 2326 goto load_quota; 2327 } 2328 if (flags & DQUOT_USAGE_ENABLED && 2329 sb_has_quota_usage_enabled(sb, type)) { 2330 ret = -EBUSY; 2331 goto out_lock; 2332 } 2333 if (flags & DQUOT_LIMITS_ENABLED && 2334 sb_has_quota_limits_enabled(sb, type)) { 2335 ret = -EBUSY; 2336 goto out_lock; 2337 } 2338 spin_lock(&dq_state_lock); 2339 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2340 spin_unlock(&dq_state_lock); 2341out_lock: 2342 mutex_unlock(&dqopt->dqonoff_mutex); 2343 return ret; 2344 } 2345 2346load_quota: 2347 return vfs_load_quota_inode(inode, type, format_id, flags); 2348} 2349EXPORT_SYMBOL(dquot_enable); 2350 2351/* 2352 * This function is used when filesystem needs to initialize quotas 2353 * during mount time. 2354 */ 2355int dquot_quota_on_mount(struct super_block *sb, char *qf_name, 2356 int format_id, int type) 2357{ 2358 struct dentry *dentry; 2359 int error; 2360 2361 mutex_lock(&sb->s_root->d_inode->i_mutex); 2362 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2363 mutex_unlock(&sb->s_root->d_inode->i_mutex); 2364 if (IS_ERR(dentry)) 2365 return PTR_ERR(dentry); 2366 2367 if (!dentry->d_inode) { 2368 error = -ENOENT; 2369 goto out; 2370 } 2371 2372 error = security_quota_on(dentry); 2373 if (!error) 2374 error = vfs_load_quota_inode(dentry->d_inode, type, format_id, 2375 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2376 2377out: 2378 dput(dentry); 2379 return error; 2380} 2381EXPORT_SYMBOL(dquot_quota_on_mount); 2382 2383static inline qsize_t qbtos(qsize_t blocks) 2384{ 2385 return blocks << QIF_DQBLKSIZE_BITS; 2386} 2387 2388static inline qsize_t stoqb(qsize_t space) 2389{ 2390 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; 2391} 2392 2393/* Generic routine for getting common part of quota structure */ 2394static void do_get_dqblk(struct dquot *dquot, struct fs_disk_quota *di) 2395{ 2396 struct mem_dqblk *dm = &dquot->dq_dqb; 2397 2398 memset(di, 0, sizeof(*di)); 2399 di->d_version = FS_DQUOT_VERSION; 2400 di->d_flags = dquot->dq_id.type == USRQUOTA ? 2401 FS_USER_QUOTA : FS_GROUP_QUOTA; 2402 di->d_id = from_kqid_munged(current_user_ns(), dquot->dq_id); 2403 2404 spin_lock(&dq_data_lock); 2405 di->d_blk_hardlimit = stoqb(dm->dqb_bhardlimit); 2406 di->d_blk_softlimit = stoqb(dm->dqb_bsoftlimit); 2407 di->d_ino_hardlimit = dm->dqb_ihardlimit; 2408 di->d_ino_softlimit = dm->dqb_isoftlimit; 2409 di->d_bcount = dm->dqb_curspace + dm->dqb_rsvspace; 2410 di->d_icount = dm->dqb_curinodes; 2411 di->d_btimer = dm->dqb_btime; 2412 di->d_itimer = dm->dqb_itime; 2413 spin_unlock(&dq_data_lock); 2414} 2415 2416int dquot_get_dqblk(struct super_block *sb, struct kqid qid, 2417 struct fs_disk_quota *di) 2418{ 2419 struct dquot *dquot; 2420 2421 dquot = dqget(sb, qid); 2422 if (!dquot) 2423 return -ESRCH; 2424 do_get_dqblk(dquot, di); 2425 dqput(dquot); 2426 2427 return 0; 2428} 2429EXPORT_SYMBOL(dquot_get_dqblk); 2430 2431#define VFS_FS_DQ_MASK \ 2432 (FS_DQ_BCOUNT | FS_DQ_BSOFT | FS_DQ_BHARD | \ 2433 FS_DQ_ICOUNT | FS_DQ_ISOFT | FS_DQ_IHARD | \ 2434 FS_DQ_BTIMER | FS_DQ_ITIMER) 2435 2436/* Generic routine for setting common part of quota structure */ 2437static int do_set_dqblk(struct dquot *dquot, struct fs_disk_quota *di) 2438{ 2439 struct mem_dqblk *dm = &dquot->dq_dqb; 2440 int check_blim = 0, check_ilim = 0; 2441 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 2442 2443 if (di->d_fieldmask & ~VFS_FS_DQ_MASK) 2444 return -EINVAL; 2445 2446 if (((di->d_fieldmask & FS_DQ_BSOFT) && 2447 (di->d_blk_softlimit > dqi->dqi_maxblimit)) || 2448 ((di->d_fieldmask & FS_DQ_BHARD) && 2449 (di->d_blk_hardlimit > dqi->dqi_maxblimit)) || 2450 ((di->d_fieldmask & FS_DQ_ISOFT) && 2451 (di->d_ino_softlimit > dqi->dqi_maxilimit)) || 2452 ((di->d_fieldmask & FS_DQ_IHARD) && 2453 (di->d_ino_hardlimit > dqi->dqi_maxilimit))) 2454 return -ERANGE; 2455 2456 spin_lock(&dq_data_lock); 2457 if (di->d_fieldmask & FS_DQ_BCOUNT) { 2458 dm->dqb_curspace = di->d_bcount - dm->dqb_rsvspace; 2459 check_blim = 1; 2460 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2461 } 2462 2463 if (di->d_fieldmask & FS_DQ_BSOFT) 2464 dm->dqb_bsoftlimit = qbtos(di->d_blk_softlimit); 2465 if (di->d_fieldmask & FS_DQ_BHARD) 2466 dm->dqb_bhardlimit = qbtos(di->d_blk_hardlimit); 2467 if (di->d_fieldmask & (FS_DQ_BSOFT | FS_DQ_BHARD)) { 2468 check_blim = 1; 2469 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2470 } 2471 2472 if (di->d_fieldmask & FS_DQ_ICOUNT) { 2473 dm->dqb_curinodes = di->d_icount; 2474 check_ilim = 1; 2475 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2476 } 2477 2478 if (di->d_fieldmask & FS_DQ_ISOFT) 2479 dm->dqb_isoftlimit = di->d_ino_softlimit; 2480 if (di->d_fieldmask & FS_DQ_IHARD) 2481 dm->dqb_ihardlimit = di->d_ino_hardlimit; 2482 if (di->d_fieldmask & (FS_DQ_ISOFT | FS_DQ_IHARD)) { 2483 check_ilim = 1; 2484 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2485 } 2486 2487 if (di->d_fieldmask & FS_DQ_BTIMER) { 2488 dm->dqb_btime = di->d_btimer; 2489 check_blim = 1; 2490 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2491 } 2492 2493 if (di->d_fieldmask & FS_DQ_ITIMER) { 2494 dm->dqb_itime = di->d_itimer; 2495 check_ilim = 1; 2496 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2497 } 2498 2499 if (check_blim) { 2500 if (!dm->dqb_bsoftlimit || 2501 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2502 dm->dqb_btime = 0; 2503 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2504 } else if (!(di->d_fieldmask & FS_DQ_BTIMER)) 2505 /* Set grace only if user hasn't provided his own... */ 2506 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2507 } 2508 if (check_ilim) { 2509 if (!dm->dqb_isoftlimit || 2510 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2511 dm->dqb_itime = 0; 2512 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2513 } else if (!(di->d_fieldmask & FS_DQ_ITIMER)) 2514 /* Set grace only if user hasn't provided his own... */ 2515 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2516 } 2517 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2518 dm->dqb_isoftlimit) 2519 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2520 else 2521 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2522 spin_unlock(&dq_data_lock); 2523 mark_dquot_dirty(dquot); 2524 2525 return 0; 2526} 2527 2528int dquot_set_dqblk(struct super_block *sb, struct kqid qid, 2529 struct fs_disk_quota *di) 2530{ 2531 struct dquot *dquot; 2532 int rc; 2533 2534 dquot = dqget(sb, qid); 2535 if (!dquot) { 2536 rc = -ESRCH; 2537 goto out; 2538 } 2539 rc = do_set_dqblk(dquot, di); 2540 dqput(dquot); 2541out: 2542 return rc; 2543} 2544EXPORT_SYMBOL(dquot_set_dqblk); 2545 2546/* Generic routine for getting common part of quota file information */ 2547int dquot_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2548{ 2549 struct mem_dqinfo *mi; 2550 2551 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2552 if (!sb_has_quota_active(sb, type)) { 2553 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2554 return -ESRCH; 2555 } 2556 mi = sb_dqopt(sb)->info + type; 2557 spin_lock(&dq_data_lock); 2558 ii->dqi_bgrace = mi->dqi_bgrace; 2559 ii->dqi_igrace = mi->dqi_igrace; 2560 ii->dqi_flags = mi->dqi_flags & DQF_GETINFO_MASK; 2561 ii->dqi_valid = IIF_ALL; 2562 spin_unlock(&dq_data_lock); 2563 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2564 return 0; 2565} 2566EXPORT_SYMBOL(dquot_get_dqinfo); 2567 2568/* Generic routine for setting common part of quota file information */ 2569int dquot_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2570{ 2571 struct mem_dqinfo *mi; 2572 int err = 0; 2573 2574 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2575 if (!sb_has_quota_active(sb, type)) { 2576 err = -ESRCH; 2577 goto out; 2578 } 2579 mi = sb_dqopt(sb)->info + type; 2580 spin_lock(&dq_data_lock); 2581 if (ii->dqi_valid & IIF_BGRACE) 2582 mi->dqi_bgrace = ii->dqi_bgrace; 2583 if (ii->dqi_valid & IIF_IGRACE) 2584 mi->dqi_igrace = ii->dqi_igrace; 2585 if (ii->dqi_valid & IIF_FLAGS) 2586 mi->dqi_flags = (mi->dqi_flags & ~DQF_SETINFO_MASK) | 2587 (ii->dqi_flags & DQF_SETINFO_MASK); 2588 spin_unlock(&dq_data_lock); 2589 mark_info_dirty(sb, type); 2590 /* Force write to disk */ 2591 sb->dq_op->write_info(sb, type); 2592out: 2593 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2594 return err; 2595} 2596EXPORT_SYMBOL(dquot_set_dqinfo); 2597 2598const struct quotactl_ops dquot_quotactl_ops = { 2599 .quota_on = dquot_quota_on, 2600 .quota_off = dquot_quota_off, 2601 .quota_sync = dquot_quota_sync, 2602 .get_info = dquot_get_dqinfo, 2603 .set_info = dquot_set_dqinfo, 2604 .get_dqblk = dquot_get_dqblk, 2605 .set_dqblk = dquot_set_dqblk 2606}; 2607EXPORT_SYMBOL(dquot_quotactl_ops); 2608 2609static int do_proc_dqstats(struct ctl_table *table, int write, 2610 void __user *buffer, size_t *lenp, loff_t *ppos) 2611{ 2612 unsigned int type = (int *)table->data - dqstats.stat; 2613 2614 /* Update global table */ 2615 dqstats.stat[type] = 2616 percpu_counter_sum_positive(&dqstats.counter[type]); 2617 return proc_dointvec(table, write, buffer, lenp, ppos); 2618} 2619 2620static struct ctl_table fs_dqstats_table[] = { 2621 { 2622 .procname = "lookups", 2623 .data = &dqstats.stat[DQST_LOOKUPS], 2624 .maxlen = sizeof(int), 2625 .mode = 0444, 2626 .proc_handler = do_proc_dqstats, 2627 }, 2628 { 2629 .procname = "drops", 2630 .data = &dqstats.stat[DQST_DROPS], 2631 .maxlen = sizeof(int), 2632 .mode = 0444, 2633 .proc_handler = do_proc_dqstats, 2634 }, 2635 { 2636 .procname = "reads", 2637 .data = &dqstats.stat[DQST_READS], 2638 .maxlen = sizeof(int), 2639 .mode = 0444, 2640 .proc_handler = do_proc_dqstats, 2641 }, 2642 { 2643 .procname = "writes", 2644 .data = &dqstats.stat[DQST_WRITES], 2645 .maxlen = sizeof(int), 2646 .mode = 0444, 2647 .proc_handler = do_proc_dqstats, 2648 }, 2649 { 2650 .procname = "cache_hits", 2651 .data = &dqstats.stat[DQST_CACHE_HITS], 2652 .maxlen = sizeof(int), 2653 .mode = 0444, 2654 .proc_handler = do_proc_dqstats, 2655 }, 2656 { 2657 .procname = "allocated_dquots", 2658 .data = &dqstats.stat[DQST_ALLOC_DQUOTS], 2659 .maxlen = sizeof(int), 2660 .mode = 0444, 2661 .proc_handler = do_proc_dqstats, 2662 }, 2663 { 2664 .procname = "free_dquots", 2665 .data = &dqstats.stat[DQST_FREE_DQUOTS], 2666 .maxlen = sizeof(int), 2667 .mode = 0444, 2668 .proc_handler = do_proc_dqstats, 2669 }, 2670 { 2671 .procname = "syncs", 2672 .data = &dqstats.stat[DQST_SYNCS], 2673 .maxlen = sizeof(int), 2674 .mode = 0444, 2675 .proc_handler = do_proc_dqstats, 2676 }, 2677#ifdef CONFIG_PRINT_QUOTA_WARNING 2678 { 2679 .procname = "warnings", 2680 .data = &flag_print_warnings, 2681 .maxlen = sizeof(int), 2682 .mode = 0644, 2683 .proc_handler = proc_dointvec, 2684 }, 2685#endif 2686 { }, 2687}; 2688 2689static struct ctl_table fs_table[] = { 2690 { 2691 .procname = "quota", 2692 .mode = 0555, 2693 .child = fs_dqstats_table, 2694 }, 2695 { }, 2696}; 2697 2698static struct ctl_table sys_table[] = { 2699 { 2700 .procname = "fs", 2701 .mode = 0555, 2702 .child = fs_table, 2703 }, 2704 { }, 2705}; 2706 2707static int __init dquot_init(void) 2708{ 2709 int i, ret; 2710 unsigned long nr_hash, order; 2711 2712 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2713 2714 register_sysctl_table(sys_table); 2715 2716 dquot_cachep = kmem_cache_create("dquot", 2717 sizeof(struct dquot), sizeof(unsigned long) * 4, 2718 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2719 SLAB_MEM_SPREAD|SLAB_PANIC), 2720 NULL); 2721 2722 order = 0; 2723 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2724 if (!dquot_hash) 2725 panic("Cannot create dquot hash table"); 2726 2727 for (i = 0; i < _DQST_DQSTAT_LAST; i++) { 2728 ret = percpu_counter_init(&dqstats.counter[i], 0, GFP_KERNEL); 2729 if (ret) 2730 panic("Cannot create dquot stat counters"); 2731 } 2732 2733 /* Find power-of-two hlist_heads which can fit into allocation */ 2734 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2735 dq_hash_bits = 0; 2736 do { 2737 dq_hash_bits++; 2738 } while (nr_hash >> dq_hash_bits); 2739 dq_hash_bits--; 2740 2741 nr_hash = 1UL << dq_hash_bits; 2742 dq_hash_mask = nr_hash - 1; 2743 for (i = 0; i < nr_hash; i++) 2744 INIT_HLIST_HEAD(dquot_hash + i); 2745 2746 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", 2747 nr_hash, order, (PAGE_SIZE << order)); 2748 2749 register_shrinker(&dqcache_shrinker); 2750 2751 return 0; 2752} 2753module_init(dquot_init); 2754