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 inline struct dquot **i_dquot(struct inode *inode) 897{ 898 return inode->i_sb->s_op->get_dquots(inode); 899} 900 901static int dqinit_needed(struct inode *inode, int type) 902{ 903 struct dquot * const *dquots; 904 int cnt; 905 906 if (IS_NOQUOTA(inode)) 907 return 0; 908 909 dquots = i_dquot(inode); 910 if (type != -1) 911 return !dquots[type]; 912 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 913 if (!dquots[cnt]) 914 return 1; 915 return 0; 916} 917 918/* This routine is guarded by dqonoff_mutex mutex */ 919static 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 */ 973static void remove_inode_dquot_ref(struct inode *inode, int type, 974 struct list_head *tofree_head) 975{ 976 struct dquot **dquots = i_dquot(inode); 977 struct dquot *dquot = dquots[type]; 978 979 if (!dquot) 980 return; 981 982 dquots[type] = NULL; 983 if (list_empty(&dquot->dq_free)) { 984 /* 985 * The inode still has reference to dquot so it can't be in the 986 * free list 987 */ 988 spin_lock(&dq_list_lock); 989 list_add(&dquot->dq_free, tofree_head); 990 spin_unlock(&dq_list_lock); 991 } else { 992 /* 993 * Dquot is already in a list to put so we won't drop the last 994 * reference here. 995 */ 996 dqput(dquot); 997 } 998} 999 1000/* 1001 * Free list of dquots 1002 * Dquots are removed from inodes and no new references can be got so we are 1003 * the only ones holding reference 1004 */ 1005static void put_dquot_list(struct list_head *tofree_head) 1006{ 1007 struct list_head *act_head; 1008 struct dquot *dquot; 1009 1010 act_head = tofree_head->next; 1011 while (act_head != tofree_head) { 1012 dquot = list_entry(act_head, struct dquot, dq_free); 1013 act_head = act_head->next; 1014 /* Remove dquot from the list so we won't have problems... */ 1015 list_del_init(&dquot->dq_free); 1016 dqput(dquot); 1017 } 1018} 1019 1020static void remove_dquot_ref(struct super_block *sb, int type, 1021 struct list_head *tofree_head) 1022{ 1023 struct inode *inode; 1024 int reserved = 0; 1025 1026 spin_lock(&inode_sb_list_lock); 1027 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 1028 /* 1029 * We have to scan also I_NEW inodes because they can already 1030 * have quota pointer initialized. Luckily, we need to touch 1031 * only quota pointers and these have separate locking 1032 * (dq_data_lock). 1033 */ 1034 spin_lock(&dq_data_lock); 1035 if (!IS_NOQUOTA(inode)) { 1036 if (unlikely(inode_get_rsv_space(inode) > 0)) 1037 reserved = 1; 1038 remove_inode_dquot_ref(inode, type, tofree_head); 1039 } 1040 spin_unlock(&dq_data_lock); 1041 } 1042 spin_unlock(&inode_sb_list_lock); 1043#ifdef CONFIG_QUOTA_DEBUG 1044 if (reserved) { 1045 printk(KERN_WARNING "VFS (%s): Writes happened after quota" 1046 " was disabled thus quota information is probably " 1047 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 1048 } 1049#endif 1050} 1051 1052/* Gather all references from inodes and drop them */ 1053static void drop_dquot_ref(struct super_block *sb, int type) 1054{ 1055 LIST_HEAD(tofree_head); 1056 1057 if (sb->dq_op) { 1058 remove_dquot_ref(sb, type, &tofree_head); 1059 synchronize_srcu(&dquot_srcu); 1060 put_dquot_list(&tofree_head); 1061 } 1062} 1063 1064static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1065{ 1066 dquot->dq_dqb.dqb_curinodes += number; 1067} 1068 1069static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1070{ 1071 dquot->dq_dqb.dqb_curspace += number; 1072} 1073 1074static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1075{ 1076 dquot->dq_dqb.dqb_rsvspace += number; 1077} 1078 1079/* 1080 * Claim reserved quota space 1081 */ 1082static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1083{ 1084 if (dquot->dq_dqb.dqb_rsvspace < number) { 1085 WARN_ON_ONCE(1); 1086 number = dquot->dq_dqb.dqb_rsvspace; 1087 } 1088 dquot->dq_dqb.dqb_curspace += number; 1089 dquot->dq_dqb.dqb_rsvspace -= number; 1090} 1091 1092static void dquot_reclaim_reserved_space(struct dquot *dquot, qsize_t number) 1093{ 1094 if (WARN_ON_ONCE(dquot->dq_dqb.dqb_curspace < number)) 1095 number = dquot->dq_dqb.dqb_curspace; 1096 dquot->dq_dqb.dqb_rsvspace += number; 1097 dquot->dq_dqb.dqb_curspace -= number; 1098} 1099 1100static inline 1101void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1102{ 1103 if (dquot->dq_dqb.dqb_rsvspace >= number) 1104 dquot->dq_dqb.dqb_rsvspace -= number; 1105 else { 1106 WARN_ON_ONCE(1); 1107 dquot->dq_dqb.dqb_rsvspace = 0; 1108 } 1109} 1110 1111static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1112{ 1113 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1114 dquot->dq_dqb.dqb_curinodes >= number) 1115 dquot->dq_dqb.dqb_curinodes -= number; 1116 else 1117 dquot->dq_dqb.dqb_curinodes = 0; 1118 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1119 dquot->dq_dqb.dqb_itime = (time_t) 0; 1120 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1121} 1122 1123static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1124{ 1125 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1126 dquot->dq_dqb.dqb_curspace >= number) 1127 dquot->dq_dqb.dqb_curspace -= number; 1128 else 1129 dquot->dq_dqb.dqb_curspace = 0; 1130 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1131 dquot->dq_dqb.dqb_btime = (time_t) 0; 1132 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1133} 1134 1135struct dquot_warn { 1136 struct super_block *w_sb; 1137 struct kqid w_dq_id; 1138 short w_type; 1139}; 1140 1141static int warning_issued(struct dquot *dquot, const int warntype) 1142{ 1143 int flag = (warntype == QUOTA_NL_BHARDWARN || 1144 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1145 ((warntype == QUOTA_NL_IHARDWARN || 1146 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1147 1148 if (!flag) 1149 return 0; 1150 return test_and_set_bit(flag, &dquot->dq_flags); 1151} 1152 1153#ifdef CONFIG_PRINT_QUOTA_WARNING 1154static int flag_print_warnings = 1; 1155 1156static int need_print_warning(struct dquot_warn *warn) 1157{ 1158 if (!flag_print_warnings) 1159 return 0; 1160 1161 switch (warn->w_dq_id.type) { 1162 case USRQUOTA: 1163 return uid_eq(current_fsuid(), warn->w_dq_id.uid); 1164 case GRPQUOTA: 1165 return in_group_p(warn->w_dq_id.gid); 1166 case PRJQUOTA: 1167 return 1; 1168 } 1169 return 0; 1170} 1171 1172/* Print warning to user which exceeded quota */ 1173static void print_warning(struct dquot_warn *warn) 1174{ 1175 char *msg = NULL; 1176 struct tty_struct *tty; 1177 int warntype = warn->w_type; 1178 1179 if (warntype == QUOTA_NL_IHARDBELOW || 1180 warntype == QUOTA_NL_ISOFTBELOW || 1181 warntype == QUOTA_NL_BHARDBELOW || 1182 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(warn)) 1183 return; 1184 1185 tty = get_current_tty(); 1186 if (!tty) 1187 return; 1188 tty_write_message(tty, warn->w_sb->s_id); 1189 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1190 tty_write_message(tty, ": warning, "); 1191 else 1192 tty_write_message(tty, ": write failed, "); 1193 tty_write_message(tty, quotatypes[warn->w_dq_id.type]); 1194 switch (warntype) { 1195 case QUOTA_NL_IHARDWARN: 1196 msg = " file limit reached.\r\n"; 1197 break; 1198 case QUOTA_NL_ISOFTLONGWARN: 1199 msg = " file quota exceeded too long.\r\n"; 1200 break; 1201 case QUOTA_NL_ISOFTWARN: 1202 msg = " file quota exceeded.\r\n"; 1203 break; 1204 case QUOTA_NL_BHARDWARN: 1205 msg = " block limit reached.\r\n"; 1206 break; 1207 case QUOTA_NL_BSOFTLONGWARN: 1208 msg = " block quota exceeded too long.\r\n"; 1209 break; 1210 case QUOTA_NL_BSOFTWARN: 1211 msg = " block quota exceeded.\r\n"; 1212 break; 1213 } 1214 tty_write_message(tty, msg); 1215 tty_kref_put(tty); 1216} 1217#endif 1218 1219static void prepare_warning(struct dquot_warn *warn, struct dquot *dquot, 1220 int warntype) 1221{ 1222 if (warning_issued(dquot, warntype)) 1223 return; 1224 warn->w_type = warntype; 1225 warn->w_sb = dquot->dq_sb; 1226 warn->w_dq_id = dquot->dq_id; 1227} 1228 1229/* 1230 * Write warnings to the console and send warning messages over netlink. 1231 * 1232 * Note that this function can call into tty and networking code. 1233 */ 1234static void flush_warnings(struct dquot_warn *warn) 1235{ 1236 int i; 1237 1238 for (i = 0; i < MAXQUOTAS; i++) { 1239 if (warn[i].w_type == QUOTA_NL_NOWARN) 1240 continue; 1241#ifdef CONFIG_PRINT_QUOTA_WARNING 1242 print_warning(&warn[i]); 1243#endif 1244 quota_send_warning(warn[i].w_dq_id, 1245 warn[i].w_sb->s_dev, warn[i].w_type); 1246 } 1247} 1248 1249static int ignore_hardlimit(struct dquot *dquot) 1250{ 1251 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 1252 1253 return capable(CAP_SYS_RESOURCE) && 1254 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1255 !(info->dqi_flags & DQF_ROOT_SQUASH)); 1256} 1257 1258/* needs dq_data_lock */ 1259static int check_idq(struct dquot *dquot, qsize_t inodes, 1260 struct dquot_warn *warn) 1261{ 1262 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1263 1264 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type) || 1265 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1266 return 0; 1267 1268 if (dquot->dq_dqb.dqb_ihardlimit && 1269 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1270 !ignore_hardlimit(dquot)) { 1271 prepare_warning(warn, dquot, QUOTA_NL_IHARDWARN); 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 && 1278 get_seconds() >= dquot->dq_dqb.dqb_itime && 1279 !ignore_hardlimit(dquot)) { 1280 prepare_warning(warn, dquot, QUOTA_NL_ISOFTLONGWARN); 1281 return -EDQUOT; 1282 } 1283 1284 if (dquot->dq_dqb.dqb_isoftlimit && 1285 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1286 dquot->dq_dqb.dqb_itime == 0) { 1287 prepare_warning(warn, dquot, QUOTA_NL_ISOFTWARN); 1288 dquot->dq_dqb.dqb_itime = get_seconds() + 1289 sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type].dqi_igrace; 1290 } 1291 1292 return 0; 1293} 1294 1295/* needs dq_data_lock */ 1296static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, 1297 struct dquot_warn *warn) 1298{ 1299 qsize_t tspace; 1300 struct super_block *sb = dquot->dq_sb; 1301 1302 if (!sb_has_quota_limits_enabled(sb, dquot->dq_id.type) || 1303 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1304 return 0; 1305 1306 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1307 + space; 1308 1309 if (dquot->dq_dqb.dqb_bhardlimit && 1310 tspace > dquot->dq_dqb.dqb_bhardlimit && 1311 !ignore_hardlimit(dquot)) { 1312 if (!prealloc) 1313 prepare_warning(warn, dquot, QUOTA_NL_BHARDWARN); 1314 return -EDQUOT; 1315 } 1316 1317 if (dquot->dq_dqb.dqb_bsoftlimit && 1318 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1319 dquot->dq_dqb.dqb_btime && 1320 get_seconds() >= dquot->dq_dqb.dqb_btime && 1321 !ignore_hardlimit(dquot)) { 1322 if (!prealloc) 1323 prepare_warning(warn, dquot, QUOTA_NL_BSOFTLONGWARN); 1324 return -EDQUOT; 1325 } 1326 1327 if (dquot->dq_dqb.dqb_bsoftlimit && 1328 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1329 dquot->dq_dqb.dqb_btime == 0) { 1330 if (!prealloc) { 1331 prepare_warning(warn, dquot, QUOTA_NL_BSOFTWARN); 1332 dquot->dq_dqb.dqb_btime = get_seconds() + 1333 sb_dqopt(sb)->info[dquot->dq_id.type].dqi_bgrace; 1334 } 1335 else 1336 /* 1337 * We don't allow preallocation to exceed softlimit so exceeding will 1338 * be always printed 1339 */ 1340 return -EDQUOT; 1341 } 1342 1343 return 0; 1344} 1345 1346static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1347{ 1348 qsize_t newinodes; 1349 1350 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1351 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1352 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type)) 1353 return QUOTA_NL_NOWARN; 1354 1355 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1356 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1357 return QUOTA_NL_ISOFTBELOW; 1358 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1359 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1360 return QUOTA_NL_IHARDBELOW; 1361 return QUOTA_NL_NOWARN; 1362} 1363 1364static int info_bdq_free(struct dquot *dquot, qsize_t space) 1365{ 1366 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1367 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1368 return QUOTA_NL_NOWARN; 1369 1370 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1371 return QUOTA_NL_BSOFTBELOW; 1372 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1373 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1374 return QUOTA_NL_BHARDBELOW; 1375 return QUOTA_NL_NOWARN; 1376} 1377 1378static int dquot_active(const struct inode *inode) 1379{ 1380 struct super_block *sb = inode->i_sb; 1381 1382 if (IS_NOQUOTA(inode)) 1383 return 0; 1384 return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb); 1385} 1386 1387/* 1388 * Initialize quota pointers in inode 1389 * 1390 * It is better to call this function outside of any transaction as it 1391 * might need a lot of space in journal for dquot structure allocation. 1392 */ 1393static void __dquot_initialize(struct inode *inode, int type) 1394{ 1395 int cnt, init_needed = 0; 1396 struct dquot **dquots, *got[MAXQUOTAS] = {}; 1397 struct super_block *sb = inode->i_sb; 1398 qsize_t rsv; 1399 1400 if (!dquot_active(inode)) 1401 return; 1402 1403 dquots = i_dquot(inode); 1404 1405 /* First get references to structures we might need. */ 1406 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1407 struct kqid qid; 1408 kprojid_t projid; 1409 int rc; 1410 1411 if (type != -1 && cnt != type) 1412 continue; 1413 /* 1414 * The i_dquot should have been initialized in most cases, 1415 * we check it without locking here to avoid unnecessary 1416 * dqget()/dqput() calls. 1417 */ 1418 if (dquots[cnt]) 1419 continue; 1420 1421 if (!sb_has_quota_active(sb, cnt)) 1422 continue; 1423 1424 init_needed = 1; 1425 1426 switch (cnt) { 1427 case USRQUOTA: 1428 qid = make_kqid_uid(inode->i_uid); 1429 break; 1430 case GRPQUOTA: 1431 qid = make_kqid_gid(inode->i_gid); 1432 break; 1433 case PRJQUOTA: 1434 rc = inode->i_sb->dq_op->get_projid(inode, &projid); 1435 if (rc) 1436 continue; 1437 qid = make_kqid_projid(projid); 1438 break; 1439 } 1440 got[cnt] = dqget(sb, qid); 1441 } 1442 1443 /* All required i_dquot has been initialized */ 1444 if (!init_needed) 1445 return; 1446 1447 spin_lock(&dq_data_lock); 1448 if (IS_NOQUOTA(inode)) 1449 goto out_err; 1450 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1451 if (type != -1 && cnt != type) 1452 continue; 1453 /* Avoid races with quotaoff() */ 1454 if (!sb_has_quota_active(sb, cnt)) 1455 continue; 1456 /* We could race with quotaon or dqget() could have failed */ 1457 if (!got[cnt]) 1458 continue; 1459 if (!dquots[cnt]) { 1460 dquots[cnt] = got[cnt]; 1461 got[cnt] = NULL; 1462 /* 1463 * Make quota reservation system happy if someone 1464 * did a write before quota was turned on 1465 */ 1466 rsv = inode_get_rsv_space(inode); 1467 if (unlikely(rsv)) 1468 dquot_resv_space(dquots[cnt], rsv); 1469 } 1470 } 1471out_err: 1472 spin_unlock(&dq_data_lock); 1473 /* Drop unused references */ 1474 dqput_all(got); 1475} 1476 1477void dquot_initialize(struct inode *inode) 1478{ 1479 __dquot_initialize(inode, -1); 1480} 1481EXPORT_SYMBOL(dquot_initialize); 1482 1483/* 1484 * Release all quotas referenced by inode. 1485 * 1486 * This function only be called on inode free or converting 1487 * a file to quota file, no other users for the i_dquot in 1488 * both cases, so we needn't call synchronize_srcu() after 1489 * clearing i_dquot. 1490 */ 1491static void __dquot_drop(struct inode *inode) 1492{ 1493 int cnt; 1494 struct dquot **dquots = i_dquot(inode); 1495 struct dquot *put[MAXQUOTAS]; 1496 1497 spin_lock(&dq_data_lock); 1498 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1499 put[cnt] = dquots[cnt]; 1500 dquots[cnt] = NULL; 1501 } 1502 spin_unlock(&dq_data_lock); 1503 dqput_all(put); 1504} 1505 1506void dquot_drop(struct inode *inode) 1507{ 1508 struct dquot * const *dquots; 1509 int cnt; 1510 1511 if (IS_NOQUOTA(inode)) 1512 return; 1513 1514 /* 1515 * Test before calling to rule out calls from proc and such 1516 * where we are not allowed to block. Note that this is 1517 * actually reliable test even without the lock - the caller 1518 * must assure that nobody can come after the DQUOT_DROP and 1519 * add quota pointers back anyway. 1520 */ 1521 dquots = i_dquot(inode); 1522 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1523 if (dquots[cnt]) 1524 break; 1525 } 1526 1527 if (cnt < MAXQUOTAS) 1528 __dquot_drop(inode); 1529} 1530EXPORT_SYMBOL(dquot_drop); 1531 1532/* 1533 * inode_reserved_space is managed internally by quota, and protected by 1534 * i_lock similar to i_blocks+i_bytes. 1535 */ 1536static qsize_t *inode_reserved_space(struct inode * inode) 1537{ 1538 /* Filesystem must explicitly define it's own method in order to use 1539 * quota reservation interface */ 1540 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1541 return inode->i_sb->dq_op->get_reserved_space(inode); 1542} 1543 1544void inode_add_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_add_rsv_space); 1551 1552void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1553{ 1554 spin_lock(&inode->i_lock); 1555 *inode_reserved_space(inode) -= number; 1556 __inode_add_bytes(inode, number); 1557 spin_unlock(&inode->i_lock); 1558} 1559EXPORT_SYMBOL(inode_claim_rsv_space); 1560 1561void inode_reclaim_rsv_space(struct inode *inode, qsize_t number) 1562{ 1563 spin_lock(&inode->i_lock); 1564 *inode_reserved_space(inode) += number; 1565 __inode_sub_bytes(inode, number); 1566 spin_unlock(&inode->i_lock); 1567} 1568EXPORT_SYMBOL(inode_reclaim_rsv_space); 1569 1570void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1571{ 1572 spin_lock(&inode->i_lock); 1573 *inode_reserved_space(inode) -= number; 1574 spin_unlock(&inode->i_lock); 1575} 1576EXPORT_SYMBOL(inode_sub_rsv_space); 1577 1578static qsize_t inode_get_rsv_space(struct inode *inode) 1579{ 1580 qsize_t ret; 1581 1582 if (!inode->i_sb->dq_op->get_reserved_space) 1583 return 0; 1584 spin_lock(&inode->i_lock); 1585 ret = *inode_reserved_space(inode); 1586 spin_unlock(&inode->i_lock); 1587 return ret; 1588} 1589 1590static void inode_incr_space(struct inode *inode, qsize_t number, 1591 int reserve) 1592{ 1593 if (reserve) 1594 inode_add_rsv_space(inode, number); 1595 else 1596 inode_add_bytes(inode, number); 1597} 1598 1599static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1600{ 1601 if (reserve) 1602 inode_sub_rsv_space(inode, number); 1603 else 1604 inode_sub_bytes(inode, number); 1605} 1606 1607/* 1608 * This functions updates i_blocks+i_bytes fields and quota information 1609 * (together with appropriate checks). 1610 * 1611 * NOTE: We absolutely rely on the fact that caller dirties the inode 1612 * (usually helpers in quotaops.h care about this) and holds a handle for 1613 * the current transaction so that dquot write and inode write go into the 1614 * same transaction. 1615 */ 1616 1617/* 1618 * This operation can block, but only after everything is updated 1619 */ 1620int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags) 1621{ 1622 int cnt, ret = 0, index; 1623 struct dquot_warn warn[MAXQUOTAS]; 1624 int reserve = flags & DQUOT_SPACE_RESERVE; 1625 struct dquot **dquots; 1626 1627 if (!dquot_active(inode)) { 1628 inode_incr_space(inode, number, reserve); 1629 goto out; 1630 } 1631 1632 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1633 warn[cnt].w_type = QUOTA_NL_NOWARN; 1634 1635 dquots = i_dquot(inode); 1636 index = srcu_read_lock(&dquot_srcu); 1637 spin_lock(&dq_data_lock); 1638 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1639 if (!dquots[cnt]) 1640 continue; 1641 ret = check_bdq(dquots[cnt], number, 1642 !(flags & DQUOT_SPACE_WARN), &warn[cnt]); 1643 if (ret && !(flags & DQUOT_SPACE_NOFAIL)) { 1644 spin_unlock(&dq_data_lock); 1645 goto out_flush_warn; 1646 } 1647 } 1648 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1649 if (!dquots[cnt]) 1650 continue; 1651 if (reserve) 1652 dquot_resv_space(dquots[cnt], number); 1653 else 1654 dquot_incr_space(dquots[cnt], number); 1655 } 1656 inode_incr_space(inode, number, reserve); 1657 spin_unlock(&dq_data_lock); 1658 1659 if (reserve) 1660 goto out_flush_warn; 1661 mark_all_dquot_dirty(dquots); 1662out_flush_warn: 1663 srcu_read_unlock(&dquot_srcu, index); 1664 flush_warnings(warn); 1665out: 1666 return ret; 1667} 1668EXPORT_SYMBOL(__dquot_alloc_space); 1669 1670/* 1671 * This operation can block, but only after everything is updated 1672 */ 1673int dquot_alloc_inode(struct inode *inode) 1674{ 1675 int cnt, ret = 0, index; 1676 struct dquot_warn warn[MAXQUOTAS]; 1677 struct dquot * const *dquots; 1678 1679 if (!dquot_active(inode)) 1680 return 0; 1681 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1682 warn[cnt].w_type = QUOTA_NL_NOWARN; 1683 1684 dquots = i_dquot(inode); 1685 index = srcu_read_lock(&dquot_srcu); 1686 spin_lock(&dq_data_lock); 1687 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1688 if (!dquots[cnt]) 1689 continue; 1690 ret = check_idq(dquots[cnt], 1, &warn[cnt]); 1691 if (ret) 1692 goto warn_put_all; 1693 } 1694 1695 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1696 if (!dquots[cnt]) 1697 continue; 1698 dquot_incr_inodes(dquots[cnt], 1); 1699 } 1700 1701warn_put_all: 1702 spin_unlock(&dq_data_lock); 1703 if (ret == 0) 1704 mark_all_dquot_dirty(dquots); 1705 srcu_read_unlock(&dquot_srcu, index); 1706 flush_warnings(warn); 1707 return ret; 1708} 1709EXPORT_SYMBOL(dquot_alloc_inode); 1710 1711/* 1712 * Convert in-memory reserved quotas to real consumed quotas 1713 */ 1714int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1715{ 1716 struct dquot **dquots; 1717 int cnt, index; 1718 1719 if (!dquot_active(inode)) { 1720 inode_claim_rsv_space(inode, number); 1721 return 0; 1722 } 1723 1724 dquots = i_dquot(inode); 1725 index = srcu_read_lock(&dquot_srcu); 1726 spin_lock(&dq_data_lock); 1727 /* Claim reserved quotas to allocated quotas */ 1728 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1729 if (dquots[cnt]) 1730 dquot_claim_reserved_space(dquots[cnt], number); 1731 } 1732 /* Update inode bytes */ 1733 inode_claim_rsv_space(inode, number); 1734 spin_unlock(&dq_data_lock); 1735 mark_all_dquot_dirty(dquots); 1736 srcu_read_unlock(&dquot_srcu, index); 1737 return 0; 1738} 1739EXPORT_SYMBOL(dquot_claim_space_nodirty); 1740 1741/* 1742 * Convert allocated space back to in-memory reserved quotas 1743 */ 1744void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number) 1745{ 1746 struct dquot **dquots; 1747 int cnt, index; 1748 1749 if (!dquot_active(inode)) { 1750 inode_reclaim_rsv_space(inode, number); 1751 return; 1752 } 1753 1754 dquots = i_dquot(inode); 1755 index = srcu_read_lock(&dquot_srcu); 1756 spin_lock(&dq_data_lock); 1757 /* Claim reserved quotas to allocated quotas */ 1758 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1759 if (dquots[cnt]) 1760 dquot_reclaim_reserved_space(dquots[cnt], number); 1761 } 1762 /* Update inode bytes */ 1763 inode_reclaim_rsv_space(inode, number); 1764 spin_unlock(&dq_data_lock); 1765 mark_all_dquot_dirty(dquots); 1766 srcu_read_unlock(&dquot_srcu, index); 1767 return; 1768} 1769EXPORT_SYMBOL(dquot_reclaim_space_nodirty); 1770 1771/* 1772 * This operation can block, but only after everything is updated 1773 */ 1774void __dquot_free_space(struct inode *inode, qsize_t number, int flags) 1775{ 1776 unsigned int cnt; 1777 struct dquot_warn warn[MAXQUOTAS]; 1778 struct dquot **dquots; 1779 int reserve = flags & DQUOT_SPACE_RESERVE, index; 1780 1781 if (!dquot_active(inode)) { 1782 inode_decr_space(inode, number, reserve); 1783 return; 1784 } 1785 1786 dquots = i_dquot(inode); 1787 index = srcu_read_lock(&dquot_srcu); 1788 spin_lock(&dq_data_lock); 1789 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1790 int wtype; 1791 1792 warn[cnt].w_type = QUOTA_NL_NOWARN; 1793 if (!dquots[cnt]) 1794 continue; 1795 wtype = info_bdq_free(dquots[cnt], number); 1796 if (wtype != QUOTA_NL_NOWARN) 1797 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1798 if (reserve) 1799 dquot_free_reserved_space(dquots[cnt], number); 1800 else 1801 dquot_decr_space(dquots[cnt], number); 1802 } 1803 inode_decr_space(inode, number, reserve); 1804 spin_unlock(&dq_data_lock); 1805 1806 if (reserve) 1807 goto out_unlock; 1808 mark_all_dquot_dirty(dquots); 1809out_unlock: 1810 srcu_read_unlock(&dquot_srcu, index); 1811 flush_warnings(warn); 1812} 1813EXPORT_SYMBOL(__dquot_free_space); 1814 1815/* 1816 * This operation can block, but only after everything is updated 1817 */ 1818void dquot_free_inode(struct inode *inode) 1819{ 1820 unsigned int cnt; 1821 struct dquot_warn warn[MAXQUOTAS]; 1822 struct dquot * const *dquots; 1823 int index; 1824 1825 if (!dquot_active(inode)) 1826 return; 1827 1828 dquots = i_dquot(inode); 1829 index = srcu_read_lock(&dquot_srcu); 1830 spin_lock(&dq_data_lock); 1831 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1832 int wtype; 1833 1834 warn[cnt].w_type = QUOTA_NL_NOWARN; 1835 if (!dquots[cnt]) 1836 continue; 1837 wtype = info_idq_free(dquots[cnt], 1); 1838 if (wtype != QUOTA_NL_NOWARN) 1839 prepare_warning(&warn[cnt], dquots[cnt], wtype); 1840 dquot_decr_inodes(dquots[cnt], 1); 1841 } 1842 spin_unlock(&dq_data_lock); 1843 mark_all_dquot_dirty(dquots); 1844 srcu_read_unlock(&dquot_srcu, index); 1845 flush_warnings(warn); 1846} 1847EXPORT_SYMBOL(dquot_free_inode); 1848 1849/* 1850 * Transfer the number of inode and blocks from one diskquota to an other. 1851 * On success, dquot references in transfer_to are consumed and references 1852 * to original dquots that need to be released are placed there. On failure, 1853 * references are kept untouched. 1854 * 1855 * This operation can block, but only after everything is updated 1856 * A transaction must be started when entering this function. 1857 * 1858 * We are holding reference on transfer_from & transfer_to, no need to 1859 * protect them by srcu_read_lock(). 1860 */ 1861int __dquot_transfer(struct inode *inode, struct dquot **transfer_to) 1862{ 1863 qsize_t space, cur_space; 1864 qsize_t rsv_space = 0; 1865 struct dquot *transfer_from[MAXQUOTAS] = {}; 1866 int cnt, ret = 0; 1867 char is_valid[MAXQUOTAS] = {}; 1868 struct dquot_warn warn_to[MAXQUOTAS]; 1869 struct dquot_warn warn_from_inodes[MAXQUOTAS]; 1870 struct dquot_warn warn_from_space[MAXQUOTAS]; 1871 1872 if (IS_NOQUOTA(inode)) 1873 return 0; 1874 /* Initialize the arrays */ 1875 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1876 warn_to[cnt].w_type = QUOTA_NL_NOWARN; 1877 warn_from_inodes[cnt].w_type = QUOTA_NL_NOWARN; 1878 warn_from_space[cnt].w_type = QUOTA_NL_NOWARN; 1879 } 1880 1881 spin_lock(&dq_data_lock); 1882 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1883 spin_unlock(&dq_data_lock); 1884 return 0; 1885 } 1886 cur_space = inode_get_bytes(inode); 1887 rsv_space = inode_get_rsv_space(inode); 1888 space = cur_space + rsv_space; 1889 /* Build the transfer_from list and check the limits */ 1890 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1891 /* 1892 * Skip changes for same uid or gid or for turned off quota-type. 1893 */ 1894 if (!transfer_to[cnt]) 1895 continue; 1896 /* Avoid races with quotaoff() */ 1897 if (!sb_has_quota_active(inode->i_sb, cnt)) 1898 continue; 1899 is_valid[cnt] = 1; 1900 transfer_from[cnt] = i_dquot(inode)[cnt]; 1901 ret = check_idq(transfer_to[cnt], 1, &warn_to[cnt]); 1902 if (ret) 1903 goto over_quota; 1904 ret = check_bdq(transfer_to[cnt], space, 0, &warn_to[cnt]); 1905 if (ret) 1906 goto over_quota; 1907 } 1908 1909 /* 1910 * Finally perform the needed transfer from transfer_from to transfer_to 1911 */ 1912 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1913 if (!is_valid[cnt]) 1914 continue; 1915 /* Due to IO error we might not have transfer_from[] structure */ 1916 if (transfer_from[cnt]) { 1917 int wtype; 1918 wtype = info_idq_free(transfer_from[cnt], 1); 1919 if (wtype != QUOTA_NL_NOWARN) 1920 prepare_warning(&warn_from_inodes[cnt], 1921 transfer_from[cnt], wtype); 1922 wtype = info_bdq_free(transfer_from[cnt], space); 1923 if (wtype != QUOTA_NL_NOWARN) 1924 prepare_warning(&warn_from_space[cnt], 1925 transfer_from[cnt], wtype); 1926 dquot_decr_inodes(transfer_from[cnt], 1); 1927 dquot_decr_space(transfer_from[cnt], cur_space); 1928 dquot_free_reserved_space(transfer_from[cnt], 1929 rsv_space); 1930 } 1931 1932 dquot_incr_inodes(transfer_to[cnt], 1); 1933 dquot_incr_space(transfer_to[cnt], cur_space); 1934 dquot_resv_space(transfer_to[cnt], rsv_space); 1935 1936 i_dquot(inode)[cnt] = transfer_to[cnt]; 1937 } 1938 spin_unlock(&dq_data_lock); 1939 1940 mark_all_dquot_dirty(transfer_from); 1941 mark_all_dquot_dirty(transfer_to); 1942 flush_warnings(warn_to); 1943 flush_warnings(warn_from_inodes); 1944 flush_warnings(warn_from_space); 1945 /* Pass back references to put */ 1946 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1947 if (is_valid[cnt]) 1948 transfer_to[cnt] = transfer_from[cnt]; 1949 return 0; 1950over_quota: 1951 spin_unlock(&dq_data_lock); 1952 flush_warnings(warn_to); 1953 return ret; 1954} 1955EXPORT_SYMBOL(__dquot_transfer); 1956 1957/* Wrapper for transferring ownership of an inode for uid/gid only 1958 * Called from FSXXX_setattr() 1959 */ 1960int dquot_transfer(struct inode *inode, struct iattr *iattr) 1961{ 1962 struct dquot *transfer_to[MAXQUOTAS] = {}; 1963 struct super_block *sb = inode->i_sb; 1964 int ret; 1965 1966 if (!dquot_active(inode)) 1967 return 0; 1968 1969 if (iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)) 1970 transfer_to[USRQUOTA] = dqget(sb, make_kqid_uid(iattr->ia_uid)); 1971 if (iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid)) 1972 transfer_to[GRPQUOTA] = dqget(sb, make_kqid_gid(iattr->ia_gid)); 1973 1974 ret = __dquot_transfer(inode, transfer_to); 1975 dqput_all(transfer_to); 1976 return ret; 1977} 1978EXPORT_SYMBOL(dquot_transfer); 1979 1980/* 1981 * Write info of quota file to disk 1982 */ 1983int dquot_commit_info(struct super_block *sb, int type) 1984{ 1985 int ret; 1986 struct quota_info *dqopt = sb_dqopt(sb); 1987 1988 mutex_lock(&dqopt->dqio_mutex); 1989 ret = dqopt->ops[type]->write_file_info(sb, type); 1990 mutex_unlock(&dqopt->dqio_mutex); 1991 return ret; 1992} 1993EXPORT_SYMBOL(dquot_commit_info); 1994 1995/* 1996 * Definitions of diskquota operations. 1997 */ 1998const struct dquot_operations dquot_operations = { 1999 .write_dquot = dquot_commit, 2000 .acquire_dquot = dquot_acquire, 2001 .release_dquot = dquot_release, 2002 .mark_dirty = dquot_mark_dquot_dirty, 2003 .write_info = dquot_commit_info, 2004 .alloc_dquot = dquot_alloc, 2005 .destroy_dquot = dquot_destroy, 2006}; 2007EXPORT_SYMBOL(dquot_operations); 2008 2009/* 2010 * Generic helper for ->open on filesystems supporting disk quotas. 2011 */ 2012int dquot_file_open(struct inode *inode, struct file *file) 2013{ 2014 int error; 2015 2016 error = generic_file_open(inode, file); 2017 if (!error && (file->f_mode & FMODE_WRITE)) 2018 dquot_initialize(inode); 2019 return error; 2020} 2021EXPORT_SYMBOL(dquot_file_open); 2022 2023/* 2024 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 2025 */ 2026int dquot_disable(struct super_block *sb, int type, unsigned int flags) 2027{ 2028 int cnt, ret = 0; 2029 struct quota_info *dqopt = sb_dqopt(sb); 2030 struct inode *toputinode[MAXQUOTAS]; 2031 2032 /* Cannot turn off usage accounting without turning off limits, or 2033 * suspend quotas and simultaneously turn quotas off. */ 2034 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 2035 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 2036 DQUOT_USAGE_ENABLED))) 2037 return -EINVAL; 2038 2039 /* We need to serialize quota_off() for device */ 2040 mutex_lock(&dqopt->dqonoff_mutex); 2041 2042 /* 2043 * Skip everything if there's nothing to do. We have to do this because 2044 * sometimes we are called when fill_super() failed and calling 2045 * sync_fs() in such cases does no good. 2046 */ 2047 if (!sb_any_quota_loaded(sb)) { 2048 mutex_unlock(&dqopt->dqonoff_mutex); 2049 return 0; 2050 } 2051 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2052 toputinode[cnt] = NULL; 2053 if (type != -1 && cnt != type) 2054 continue; 2055 if (!sb_has_quota_loaded(sb, cnt)) 2056 continue; 2057 2058 if (flags & DQUOT_SUSPENDED) { 2059 spin_lock(&dq_state_lock); 2060 dqopt->flags |= 2061 dquot_state_flag(DQUOT_SUSPENDED, cnt); 2062 spin_unlock(&dq_state_lock); 2063 } else { 2064 spin_lock(&dq_state_lock); 2065 dqopt->flags &= ~dquot_state_flag(flags, cnt); 2066 /* Turning off suspended quotas? */ 2067 if (!sb_has_quota_loaded(sb, cnt) && 2068 sb_has_quota_suspended(sb, cnt)) { 2069 dqopt->flags &= ~dquot_state_flag( 2070 DQUOT_SUSPENDED, cnt); 2071 spin_unlock(&dq_state_lock); 2072 iput(dqopt->files[cnt]); 2073 dqopt->files[cnt] = NULL; 2074 continue; 2075 } 2076 spin_unlock(&dq_state_lock); 2077 } 2078 2079 /* We still have to keep quota loaded? */ 2080 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 2081 continue; 2082 2083 /* Note: these are blocking operations */ 2084 drop_dquot_ref(sb, cnt); 2085 invalidate_dquots(sb, cnt); 2086 /* 2087 * Now all dquots should be invalidated, all writes done so we 2088 * should be only users of the info. No locks needed. 2089 */ 2090 if (info_dirty(&dqopt->info[cnt])) 2091 sb->dq_op->write_info(sb, cnt); 2092 if (dqopt->ops[cnt]->free_file_info) 2093 dqopt->ops[cnt]->free_file_info(sb, cnt); 2094 put_quota_format(dqopt->info[cnt].dqi_format); 2095 2096 toputinode[cnt] = dqopt->files[cnt]; 2097 if (!sb_has_quota_loaded(sb, cnt)) 2098 dqopt->files[cnt] = NULL; 2099 dqopt->info[cnt].dqi_flags = 0; 2100 dqopt->info[cnt].dqi_igrace = 0; 2101 dqopt->info[cnt].dqi_bgrace = 0; 2102 dqopt->ops[cnt] = NULL; 2103 } 2104 mutex_unlock(&dqopt->dqonoff_mutex); 2105 2106 /* Skip syncing and setting flags if quota files are hidden */ 2107 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2108 goto put_inodes; 2109 2110 /* Sync the superblock so that buffers with quota data are written to 2111 * disk (and so userspace sees correct data afterwards). */ 2112 if (sb->s_op->sync_fs) 2113 sb->s_op->sync_fs(sb, 1); 2114 sync_blockdev(sb->s_bdev); 2115 /* Now the quota files are just ordinary files and we can set the 2116 * inode flags back. Moreover we discard the pagecache so that 2117 * userspace sees the writes we did bypassing the pagecache. We 2118 * must also discard the blockdev buffers so that we see the 2119 * changes done by userspace on the next quotaon() */ 2120 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2121 if (toputinode[cnt]) { 2122 mutex_lock(&dqopt->dqonoff_mutex); 2123 /* If quota was reenabled in the meantime, we have 2124 * nothing to do */ 2125 if (!sb_has_quota_loaded(sb, cnt)) { 2126 mutex_lock(&toputinode[cnt]->i_mutex); 2127 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 2128 S_NOATIME | S_NOQUOTA); 2129 truncate_inode_pages(&toputinode[cnt]->i_data, 2130 0); 2131 mutex_unlock(&toputinode[cnt]->i_mutex); 2132 mark_inode_dirty_sync(toputinode[cnt]); 2133 } 2134 mutex_unlock(&dqopt->dqonoff_mutex); 2135 } 2136 if (sb->s_bdev) 2137 invalidate_bdev(sb->s_bdev); 2138put_inodes: 2139 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2140 if (toputinode[cnt]) { 2141 /* On remount RO, we keep the inode pointer so that we 2142 * can reenable quota on the subsequent remount RW. We 2143 * have to check 'flags' variable and not use sb_has_ 2144 * function because another quotaon / quotaoff could 2145 * change global state before we got here. We refuse 2146 * to suspend quotas when there is pending delete on 2147 * the quota file... */ 2148 if (!(flags & DQUOT_SUSPENDED)) 2149 iput(toputinode[cnt]); 2150 else if (!toputinode[cnt]->i_nlink) 2151 ret = -EBUSY; 2152 } 2153 return ret; 2154} 2155EXPORT_SYMBOL(dquot_disable); 2156 2157int dquot_quota_off(struct super_block *sb, int type) 2158{ 2159 return dquot_disable(sb, type, 2160 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2161} 2162EXPORT_SYMBOL(dquot_quota_off); 2163 2164/* 2165 * Turn quotas on on a device 2166 */ 2167 2168/* 2169 * Helper function to turn quotas on when we already have the inode of 2170 * quota file and no quota information is loaded. 2171 */ 2172static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 2173 unsigned int flags) 2174{ 2175 struct quota_format_type *fmt = find_quota_format(format_id); 2176 struct super_block *sb = inode->i_sb; 2177 struct quota_info *dqopt = sb_dqopt(sb); 2178 int error; 2179 int oldflags = -1; 2180 2181 if (!fmt) 2182 return -ESRCH; 2183 if (!S_ISREG(inode->i_mode)) { 2184 error = -EACCES; 2185 goto out_fmt; 2186 } 2187 if (IS_RDONLY(inode)) { 2188 error = -EROFS; 2189 goto out_fmt; 2190 } 2191 if (!sb->s_op->quota_write || !sb->s_op->quota_read || 2192 (type == PRJQUOTA && sb->dq_op->get_projid == NULL)) { 2193 error = -EINVAL; 2194 goto out_fmt; 2195 } 2196 /* Usage always has to be set... */ 2197 if (!(flags & DQUOT_USAGE_ENABLED)) { 2198 error = -EINVAL; 2199 goto out_fmt; 2200 } 2201 2202 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2203 /* As we bypass the pagecache we must now flush all the 2204 * dirty data and invalidate caches so that kernel sees 2205 * changes from userspace. It is not enough to just flush 2206 * the quota file since if blocksize < pagesize, invalidation 2207 * of the cache could fail because of other unrelated dirty 2208 * data */ 2209 sync_filesystem(sb); 2210 invalidate_bdev(sb->s_bdev); 2211 } 2212 mutex_lock(&dqopt->dqonoff_mutex); 2213 if (sb_has_quota_loaded(sb, type)) { 2214 error = -EBUSY; 2215 goto out_lock; 2216 } 2217 2218 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2219 /* We don't want quota and atime on quota files (deadlocks 2220 * possible) Also nobody should write to the file - we use 2221 * special IO operations which ignore the immutable bit. */ 2222 mutex_lock(&inode->i_mutex); 2223 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2224 S_NOQUOTA); 2225 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2226 mutex_unlock(&inode->i_mutex); 2227 /* 2228 * When S_NOQUOTA is set, remove dquot references as no more 2229 * references can be added 2230 */ 2231 __dquot_drop(inode); 2232 } 2233 2234 error = -EIO; 2235 dqopt->files[type] = igrab(inode); 2236 if (!dqopt->files[type]) 2237 goto out_lock; 2238 error = -EINVAL; 2239 if (!fmt->qf_ops->check_quota_file(sb, type)) 2240 goto out_file_init; 2241 2242 dqopt->ops[type] = fmt->qf_ops; 2243 dqopt->info[type].dqi_format = fmt; 2244 dqopt->info[type].dqi_fmt_id = format_id; 2245 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2246 mutex_lock(&dqopt->dqio_mutex); 2247 error = dqopt->ops[type]->read_file_info(sb, type); 2248 if (error < 0) { 2249 mutex_unlock(&dqopt->dqio_mutex); 2250 goto out_file_init; 2251 } 2252 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 2253 dqopt->info[type].dqi_flags |= DQF_SYS_FILE; 2254 mutex_unlock(&dqopt->dqio_mutex); 2255 spin_lock(&dq_state_lock); 2256 dqopt->flags |= dquot_state_flag(flags, type); 2257 spin_unlock(&dq_state_lock); 2258 2259 add_dquot_ref(sb, type); 2260 mutex_unlock(&dqopt->dqonoff_mutex); 2261 2262 return 0; 2263 2264out_file_init: 2265 dqopt->files[type] = NULL; 2266 iput(inode); 2267out_lock: 2268 if (oldflags != -1) { 2269 mutex_lock(&inode->i_mutex); 2270 /* Set the flags back (in the case of accidental quotaon() 2271 * on a wrong file we don't want to mess up the flags) */ 2272 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2273 inode->i_flags |= oldflags; 2274 mutex_unlock(&inode->i_mutex); 2275 } 2276 mutex_unlock(&dqopt->dqonoff_mutex); 2277out_fmt: 2278 put_quota_format(fmt); 2279 2280 return error; 2281} 2282 2283/* Reenable quotas on remount RW */ 2284int dquot_resume(struct super_block *sb, int type) 2285{ 2286 struct quota_info *dqopt = sb_dqopt(sb); 2287 struct inode *inode; 2288 int ret = 0, cnt; 2289 unsigned int flags; 2290 2291 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2292 if (type != -1 && cnt != type) 2293 continue; 2294 2295 mutex_lock(&dqopt->dqonoff_mutex); 2296 if (!sb_has_quota_suspended(sb, cnt)) { 2297 mutex_unlock(&dqopt->dqonoff_mutex); 2298 continue; 2299 } 2300 inode = dqopt->files[cnt]; 2301 dqopt->files[cnt] = NULL; 2302 spin_lock(&dq_state_lock); 2303 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2304 DQUOT_LIMITS_ENABLED, 2305 cnt); 2306 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt); 2307 spin_unlock(&dq_state_lock); 2308 mutex_unlock(&dqopt->dqonoff_mutex); 2309 2310 flags = dquot_generic_flag(flags, cnt); 2311 ret = vfs_load_quota_inode(inode, cnt, 2312 dqopt->info[cnt].dqi_fmt_id, flags); 2313 iput(inode); 2314 } 2315 2316 return ret; 2317} 2318EXPORT_SYMBOL(dquot_resume); 2319 2320int dquot_quota_on(struct super_block *sb, int type, int format_id, 2321 struct path *path) 2322{ 2323 int error = security_quota_on(path->dentry); 2324 if (error) 2325 return error; 2326 /* Quota file not on the same filesystem? */ 2327 if (path->dentry->d_sb != sb) 2328 error = -EXDEV; 2329 else 2330 error = vfs_load_quota_inode(d_inode(path->dentry), type, 2331 format_id, DQUOT_USAGE_ENABLED | 2332 DQUOT_LIMITS_ENABLED); 2333 return error; 2334} 2335EXPORT_SYMBOL(dquot_quota_on); 2336 2337/* 2338 * More powerful function for turning on quotas allowing setting 2339 * of individual quota flags 2340 */ 2341int dquot_enable(struct inode *inode, int type, int format_id, 2342 unsigned int flags) 2343{ 2344 int ret = 0; 2345 struct super_block *sb = inode->i_sb; 2346 struct quota_info *dqopt = sb_dqopt(sb); 2347 2348 /* Just unsuspend quotas? */ 2349 BUG_ON(flags & DQUOT_SUSPENDED); 2350 2351 if (!flags) 2352 return 0; 2353 /* Just updating flags needed? */ 2354 if (sb_has_quota_loaded(sb, type)) { 2355 mutex_lock(&dqopt->dqonoff_mutex); 2356 /* Now do a reliable test... */ 2357 if (!sb_has_quota_loaded(sb, type)) { 2358 mutex_unlock(&dqopt->dqonoff_mutex); 2359 goto load_quota; 2360 } 2361 if (flags & DQUOT_USAGE_ENABLED && 2362 sb_has_quota_usage_enabled(sb, type)) { 2363 ret = -EBUSY; 2364 goto out_lock; 2365 } 2366 if (flags & DQUOT_LIMITS_ENABLED && 2367 sb_has_quota_limits_enabled(sb, type)) { 2368 ret = -EBUSY; 2369 goto out_lock; 2370 } 2371 spin_lock(&dq_state_lock); 2372 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2373 spin_unlock(&dq_state_lock); 2374out_lock: 2375 mutex_unlock(&dqopt->dqonoff_mutex); 2376 return ret; 2377 } 2378 2379load_quota: 2380 return vfs_load_quota_inode(inode, type, format_id, flags); 2381} 2382EXPORT_SYMBOL(dquot_enable); 2383 2384/* 2385 * This function is used when filesystem needs to initialize quotas 2386 * during mount time. 2387 */ 2388int dquot_quota_on_mount(struct super_block *sb, char *qf_name, 2389 int format_id, int type) 2390{ 2391 struct dentry *dentry; 2392 int error; 2393 2394 mutex_lock(&d_inode(sb->s_root)->i_mutex); 2395 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2396 mutex_unlock(&d_inode(sb->s_root)->i_mutex); 2397 if (IS_ERR(dentry)) 2398 return PTR_ERR(dentry); 2399 2400 if (d_really_is_negative(dentry)) { 2401 error = -ENOENT; 2402 goto out; 2403 } 2404 2405 error = security_quota_on(dentry); 2406 if (!error) 2407 error = vfs_load_quota_inode(d_inode(dentry), type, format_id, 2408 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2409 2410out: 2411 dput(dentry); 2412 return error; 2413} 2414EXPORT_SYMBOL(dquot_quota_on_mount); 2415 2416static int dquot_quota_enable(struct super_block *sb, unsigned int flags) 2417{ 2418 int ret; 2419 int type; 2420 struct quota_info *dqopt = sb_dqopt(sb); 2421 2422 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) 2423 return -ENOSYS; 2424 /* Accounting cannot be turned on while fs is mounted */ 2425 flags &= ~(FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT); 2426 if (!flags) 2427 return -EINVAL; 2428 for (type = 0; type < MAXQUOTAS; type++) { 2429 if (!(flags & qtype_enforce_flag(type))) 2430 continue; 2431 /* Can't enforce without accounting */ 2432 if (!sb_has_quota_usage_enabled(sb, type)) 2433 return -EINVAL; 2434 ret = dquot_enable(dqopt->files[type], type, 2435 dqopt->info[type].dqi_fmt_id, 2436 DQUOT_LIMITS_ENABLED); 2437 if (ret < 0) 2438 goto out_err; 2439 } 2440 return 0; 2441out_err: 2442 /* Backout enforcement enablement we already did */ 2443 for (type--; type >= 0; type--) { 2444 if (flags & qtype_enforce_flag(type)) 2445 dquot_disable(sb, type, DQUOT_LIMITS_ENABLED); 2446 } 2447 /* Error code translation for better compatibility with XFS */ 2448 if (ret == -EBUSY) 2449 ret = -EEXIST; 2450 return ret; 2451} 2452 2453static int dquot_quota_disable(struct super_block *sb, unsigned int flags) 2454{ 2455 int ret; 2456 int type; 2457 struct quota_info *dqopt = sb_dqopt(sb); 2458 2459 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) 2460 return -ENOSYS; 2461 /* 2462 * We don't support turning off accounting via quotactl. In principle 2463 * quota infrastructure can do this but filesystems don't expect 2464 * userspace to be able to do it. 2465 */ 2466 if (flags & 2467 (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT)) 2468 return -EOPNOTSUPP; 2469 2470 /* Filter out limits not enabled */ 2471 for (type = 0; type < MAXQUOTAS; type++) 2472 if (!sb_has_quota_limits_enabled(sb, type)) 2473 flags &= ~qtype_enforce_flag(type); 2474 /* Nothing left? */ 2475 if (!flags) 2476 return -EEXIST; 2477 for (type = 0; type < MAXQUOTAS; type++) { 2478 if (flags & qtype_enforce_flag(type)) { 2479 ret = dquot_disable(sb, type, DQUOT_LIMITS_ENABLED); 2480 if (ret < 0) 2481 goto out_err; 2482 } 2483 } 2484 return 0; 2485out_err: 2486 /* Backout enforcement disabling we already did */ 2487 for (type--; type >= 0; type--) { 2488 if (flags & qtype_enforce_flag(type)) 2489 dquot_enable(dqopt->files[type], type, 2490 dqopt->info[type].dqi_fmt_id, 2491 DQUOT_LIMITS_ENABLED); 2492 } 2493 return ret; 2494} 2495 2496/* Generic routine for getting common part of quota structure */ 2497static void do_get_dqblk(struct dquot *dquot, struct qc_dqblk *di) 2498{ 2499 struct mem_dqblk *dm = &dquot->dq_dqb; 2500 2501 memset(di, 0, sizeof(*di)); 2502 spin_lock(&dq_data_lock); 2503 di->d_spc_hardlimit = dm->dqb_bhardlimit; 2504 di->d_spc_softlimit = dm->dqb_bsoftlimit; 2505 di->d_ino_hardlimit = dm->dqb_ihardlimit; 2506 di->d_ino_softlimit = dm->dqb_isoftlimit; 2507 di->d_space = dm->dqb_curspace + dm->dqb_rsvspace; 2508 di->d_ino_count = dm->dqb_curinodes; 2509 di->d_spc_timer = dm->dqb_btime; 2510 di->d_ino_timer = dm->dqb_itime; 2511 spin_unlock(&dq_data_lock); 2512} 2513 2514int dquot_get_dqblk(struct super_block *sb, struct kqid qid, 2515 struct qc_dqblk *di) 2516{ 2517 struct dquot *dquot; 2518 2519 dquot = dqget(sb, qid); 2520 if (!dquot) 2521 return -ESRCH; 2522 do_get_dqblk(dquot, di); 2523 dqput(dquot); 2524 2525 return 0; 2526} 2527EXPORT_SYMBOL(dquot_get_dqblk); 2528 2529#define VFS_QC_MASK \ 2530 (QC_SPACE | QC_SPC_SOFT | QC_SPC_HARD | \ 2531 QC_INO_COUNT | QC_INO_SOFT | QC_INO_HARD | \ 2532 QC_SPC_TIMER | QC_INO_TIMER) 2533 2534/* Generic routine for setting common part of quota structure */ 2535static int do_set_dqblk(struct dquot *dquot, struct qc_dqblk *di) 2536{ 2537 struct mem_dqblk *dm = &dquot->dq_dqb; 2538 int check_blim = 0, check_ilim = 0; 2539 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type]; 2540 2541 if (di->d_fieldmask & ~VFS_QC_MASK) 2542 return -EINVAL; 2543 2544 if (((di->d_fieldmask & QC_SPC_SOFT) && 2545 di->d_spc_softlimit > dqi->dqi_max_spc_limit) || 2546 ((di->d_fieldmask & QC_SPC_HARD) && 2547 di->d_spc_hardlimit > dqi->dqi_max_spc_limit) || 2548 ((di->d_fieldmask & QC_INO_SOFT) && 2549 (di->d_ino_softlimit > dqi->dqi_max_ino_limit)) || 2550 ((di->d_fieldmask & QC_INO_HARD) && 2551 (di->d_ino_hardlimit > dqi->dqi_max_ino_limit))) 2552 return -ERANGE; 2553 2554 spin_lock(&dq_data_lock); 2555 if (di->d_fieldmask & QC_SPACE) { 2556 dm->dqb_curspace = di->d_space - dm->dqb_rsvspace; 2557 check_blim = 1; 2558 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2559 } 2560 2561 if (di->d_fieldmask & QC_SPC_SOFT) 2562 dm->dqb_bsoftlimit = di->d_spc_softlimit; 2563 if (di->d_fieldmask & QC_SPC_HARD) 2564 dm->dqb_bhardlimit = di->d_spc_hardlimit; 2565 if (di->d_fieldmask & (QC_SPC_SOFT | QC_SPC_HARD)) { 2566 check_blim = 1; 2567 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2568 } 2569 2570 if (di->d_fieldmask & QC_INO_COUNT) { 2571 dm->dqb_curinodes = di->d_ino_count; 2572 check_ilim = 1; 2573 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2574 } 2575 2576 if (di->d_fieldmask & QC_INO_SOFT) 2577 dm->dqb_isoftlimit = di->d_ino_softlimit; 2578 if (di->d_fieldmask & QC_INO_HARD) 2579 dm->dqb_ihardlimit = di->d_ino_hardlimit; 2580 if (di->d_fieldmask & (QC_INO_SOFT | QC_INO_HARD)) { 2581 check_ilim = 1; 2582 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2583 } 2584 2585 if (di->d_fieldmask & QC_SPC_TIMER) { 2586 dm->dqb_btime = di->d_spc_timer; 2587 check_blim = 1; 2588 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2589 } 2590 2591 if (di->d_fieldmask & QC_INO_TIMER) { 2592 dm->dqb_itime = di->d_ino_timer; 2593 check_ilim = 1; 2594 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2595 } 2596 2597 if (check_blim) { 2598 if (!dm->dqb_bsoftlimit || 2599 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2600 dm->dqb_btime = 0; 2601 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2602 } else if (!(di->d_fieldmask & QC_SPC_TIMER)) 2603 /* Set grace only if user hasn't provided his own... */ 2604 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2605 } 2606 if (check_ilim) { 2607 if (!dm->dqb_isoftlimit || 2608 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2609 dm->dqb_itime = 0; 2610 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2611 } else if (!(di->d_fieldmask & QC_INO_TIMER)) 2612 /* Set grace only if user hasn't provided his own... */ 2613 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2614 } 2615 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2616 dm->dqb_isoftlimit) 2617 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2618 else 2619 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2620 spin_unlock(&dq_data_lock); 2621 mark_dquot_dirty(dquot); 2622 2623 return 0; 2624} 2625 2626int dquot_set_dqblk(struct super_block *sb, struct kqid qid, 2627 struct qc_dqblk *di) 2628{ 2629 struct dquot *dquot; 2630 int rc; 2631 2632 dquot = dqget(sb, qid); 2633 if (!dquot) { 2634 rc = -ESRCH; 2635 goto out; 2636 } 2637 rc = do_set_dqblk(dquot, di); 2638 dqput(dquot); 2639out: 2640 return rc; 2641} 2642EXPORT_SYMBOL(dquot_set_dqblk); 2643 2644/* Generic routine for getting common part of quota file information */ 2645int dquot_get_state(struct super_block *sb, struct qc_state *state) 2646{ 2647 struct mem_dqinfo *mi; 2648 struct qc_type_state *tstate; 2649 struct quota_info *dqopt = sb_dqopt(sb); 2650 int type; 2651 2652 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2653 memset(state, 0, sizeof(*state)); 2654 for (type = 0; type < MAXQUOTAS; type++) { 2655 if (!sb_has_quota_active(sb, type)) 2656 continue; 2657 tstate = state->s_state + type; 2658 mi = sb_dqopt(sb)->info + type; 2659 tstate->flags = QCI_ACCT_ENABLED; 2660 spin_lock(&dq_data_lock); 2661 if (mi->dqi_flags & DQF_SYS_FILE) 2662 tstate->flags |= QCI_SYSFILE; 2663 if (mi->dqi_flags & DQF_ROOT_SQUASH) 2664 tstate->flags |= QCI_ROOT_SQUASH; 2665 if (sb_has_quota_limits_enabled(sb, type)) 2666 tstate->flags |= QCI_LIMITS_ENFORCED; 2667 tstate->spc_timelimit = mi->dqi_bgrace; 2668 tstate->ino_timelimit = mi->dqi_igrace; 2669 tstate->ino = dqopt->files[type]->i_ino; 2670 tstate->blocks = dqopt->files[type]->i_blocks; 2671 tstate->nextents = 1; /* We don't know... */ 2672 spin_unlock(&dq_data_lock); 2673 } 2674 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2675 return 0; 2676} 2677EXPORT_SYMBOL(dquot_get_state); 2678 2679/* Generic routine for setting common part of quota file information */ 2680int dquot_set_dqinfo(struct super_block *sb, int type, struct qc_info *ii) 2681{ 2682 struct mem_dqinfo *mi; 2683 int err = 0; 2684 2685 if ((ii->i_fieldmask & QC_WARNS_MASK) || 2686 (ii->i_fieldmask & QC_RT_SPC_TIMER)) 2687 return -EINVAL; 2688 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2689 if (!sb_has_quota_active(sb, type)) { 2690 err = -ESRCH; 2691 goto out; 2692 } 2693 mi = sb_dqopt(sb)->info + type; 2694 if (ii->i_fieldmask & QC_FLAGS) { 2695 if ((ii->i_flags & QCI_ROOT_SQUASH && 2696 mi->dqi_format->qf_fmt_id != QFMT_VFS_OLD)) { 2697 err = -EINVAL; 2698 goto out; 2699 } 2700 } 2701 spin_lock(&dq_data_lock); 2702 if (ii->i_fieldmask & QC_SPC_TIMER) 2703 mi->dqi_bgrace = ii->i_spc_timelimit; 2704 if (ii->i_fieldmask & QC_INO_TIMER) 2705 mi->dqi_igrace = ii->i_ino_timelimit; 2706 if (ii->i_fieldmask & QC_FLAGS) { 2707 if (ii->i_flags & QCI_ROOT_SQUASH) 2708 mi->dqi_flags |= DQF_ROOT_SQUASH; 2709 else 2710 mi->dqi_flags &= ~DQF_ROOT_SQUASH; 2711 } 2712 spin_unlock(&dq_data_lock); 2713 mark_info_dirty(sb, type); 2714 /* Force write to disk */ 2715 sb->dq_op->write_info(sb, type); 2716out: 2717 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2718 return err; 2719} 2720EXPORT_SYMBOL(dquot_set_dqinfo); 2721 2722const struct quotactl_ops dquot_quotactl_ops = { 2723 .quota_on = dquot_quota_on, 2724 .quota_off = dquot_quota_off, 2725 .quota_sync = dquot_quota_sync, 2726 .get_state = dquot_get_state, 2727 .set_info = dquot_set_dqinfo, 2728 .get_dqblk = dquot_get_dqblk, 2729 .set_dqblk = dquot_set_dqblk 2730}; 2731EXPORT_SYMBOL(dquot_quotactl_ops); 2732 2733const struct quotactl_ops dquot_quotactl_sysfile_ops = { 2734 .quota_enable = dquot_quota_enable, 2735 .quota_disable = dquot_quota_disable, 2736 .quota_sync = dquot_quota_sync, 2737 .get_state = dquot_get_state, 2738 .set_info = dquot_set_dqinfo, 2739 .get_dqblk = dquot_get_dqblk, 2740 .set_dqblk = dquot_set_dqblk 2741}; 2742EXPORT_SYMBOL(dquot_quotactl_sysfile_ops); 2743 2744static int do_proc_dqstats(struct ctl_table *table, int write, 2745 void __user *buffer, size_t *lenp, loff_t *ppos) 2746{ 2747 unsigned int type = (int *)table->data - dqstats.stat; 2748 2749 /* Update global table */ 2750 dqstats.stat[type] = 2751 percpu_counter_sum_positive(&dqstats.counter[type]); 2752 return proc_dointvec(table, write, buffer, lenp, ppos); 2753} 2754 2755static struct ctl_table fs_dqstats_table[] = { 2756 { 2757 .procname = "lookups", 2758 .data = &dqstats.stat[DQST_LOOKUPS], 2759 .maxlen = sizeof(int), 2760 .mode = 0444, 2761 .proc_handler = do_proc_dqstats, 2762 }, 2763 { 2764 .procname = "drops", 2765 .data = &dqstats.stat[DQST_DROPS], 2766 .maxlen = sizeof(int), 2767 .mode = 0444, 2768 .proc_handler = do_proc_dqstats, 2769 }, 2770 { 2771 .procname = "reads", 2772 .data = &dqstats.stat[DQST_READS], 2773 .maxlen = sizeof(int), 2774 .mode = 0444, 2775 .proc_handler = do_proc_dqstats, 2776 }, 2777 { 2778 .procname = "writes", 2779 .data = &dqstats.stat[DQST_WRITES], 2780 .maxlen = sizeof(int), 2781 .mode = 0444, 2782 .proc_handler = do_proc_dqstats, 2783 }, 2784 { 2785 .procname = "cache_hits", 2786 .data = &dqstats.stat[DQST_CACHE_HITS], 2787 .maxlen = sizeof(int), 2788 .mode = 0444, 2789 .proc_handler = do_proc_dqstats, 2790 }, 2791 { 2792 .procname = "allocated_dquots", 2793 .data = &dqstats.stat[DQST_ALLOC_DQUOTS], 2794 .maxlen = sizeof(int), 2795 .mode = 0444, 2796 .proc_handler = do_proc_dqstats, 2797 }, 2798 { 2799 .procname = "free_dquots", 2800 .data = &dqstats.stat[DQST_FREE_DQUOTS], 2801 .maxlen = sizeof(int), 2802 .mode = 0444, 2803 .proc_handler = do_proc_dqstats, 2804 }, 2805 { 2806 .procname = "syncs", 2807 .data = &dqstats.stat[DQST_SYNCS], 2808 .maxlen = sizeof(int), 2809 .mode = 0444, 2810 .proc_handler = do_proc_dqstats, 2811 }, 2812#ifdef CONFIG_PRINT_QUOTA_WARNING 2813 { 2814 .procname = "warnings", 2815 .data = &flag_print_warnings, 2816 .maxlen = sizeof(int), 2817 .mode = 0644, 2818 .proc_handler = proc_dointvec, 2819 }, 2820#endif 2821 { }, 2822}; 2823 2824static struct ctl_table fs_table[] = { 2825 { 2826 .procname = "quota", 2827 .mode = 0555, 2828 .child = fs_dqstats_table, 2829 }, 2830 { }, 2831}; 2832 2833static struct ctl_table sys_table[] = { 2834 { 2835 .procname = "fs", 2836 .mode = 0555, 2837 .child = fs_table, 2838 }, 2839 { }, 2840}; 2841 2842static int __init dquot_init(void) 2843{ 2844 int i, ret; 2845 unsigned long nr_hash, order; 2846 2847 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2848 2849 register_sysctl_table(sys_table); 2850 2851 dquot_cachep = kmem_cache_create("dquot", 2852 sizeof(struct dquot), sizeof(unsigned long) * 4, 2853 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2854 SLAB_MEM_SPREAD|SLAB_PANIC), 2855 NULL); 2856 2857 order = 0; 2858 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2859 if (!dquot_hash) 2860 panic("Cannot create dquot hash table"); 2861 2862 for (i = 0; i < _DQST_DQSTAT_LAST; i++) { 2863 ret = percpu_counter_init(&dqstats.counter[i], 0, GFP_KERNEL); 2864 if (ret) 2865 panic("Cannot create dquot stat counters"); 2866 } 2867 2868 /* Find power-of-two hlist_heads which can fit into allocation */ 2869 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2870 dq_hash_bits = 0; 2871 do { 2872 dq_hash_bits++; 2873 } while (nr_hash >> dq_hash_bits); 2874 dq_hash_bits--; 2875 2876 nr_hash = 1UL << dq_hash_bits; 2877 dq_hash_mask = nr_hash - 1; 2878 for (i = 0; i < nr_hash; i++) 2879 INIT_HLIST_HEAD(dquot_hash + i); 2880 2881 pr_info("VFS: Dquot-cache hash table entries: %ld (order %ld," 2882 " %ld bytes)\n", nr_hash, order, (PAGE_SIZE << order)); 2883 2884 register_shrinker(&dqcache_shrinker); 2885 2886 return 0; 2887} 2888module_init(dquot_init); 2889