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/kmod.h> 75#include <linux/namei.h> 76#include <linux/buffer_head.h> 77#include <linux/capability.h> 78#include <linux/quotaops.h> 79#include <linux/writeback.h> /* for inode_lock, oddly enough.. */ 80 81#include <asm/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 * Any operation working on dquots via inode pointers must hold dqptr_sem. If 100 * operation is just reading pointers from inode (or not using them at all) the 101 * read lock is enough. If pointers are altered function must hold write lock. 102 * Special care needs to be taken about S_NOQUOTA inode flag (marking that 103 * inode is a quota file). Functions adding pointers from inode to dquots have 104 * to check this flag under dqptr_sem and then (if S_NOQUOTA is not set) they 105 * have to do all pointer modifications before dropping dqptr_sem. This makes 106 * sure they cannot race with quotaon which first sets S_NOQUOTA flag and 107 * then drops all pointers to dquots from an inode. 108 * 109 * Each dquot has its dq_lock mutex. Locked dquots might not be referenced 110 * from inodes (dquot_alloc_space() and such don't check the dq_lock). 111 * Currently dquot is locked only when it is being read to memory (or space for 112 * it is being allocated) on the first dqget() and when it is being released on 113 * the last dqput(). The allocation and release oparations are serialized by 114 * the dq_lock and by checking the use count in dquot_release(). Write 115 * operations on dquots don't hold dq_lock as they copy data under dq_data_lock 116 * spinlock to internal buffers before writing. 117 * 118 * Lock ordering (including related VFS locks) is the following: 119 * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock > 120 * dqio_mutex 121 * The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem > 122 * dqptr_sem. But filesystem has to count with the fact that functions such as 123 * dquot_alloc_space() acquire dqptr_sem and they usually have to be called 124 * from inside a transaction to keep filesystem consistency after a crash. Also 125 * filesystems usually want to do some IO on dquot from ->mark_dirty which is 126 * called with dqptr_sem held. 127 * i_mutex on quota files is special (it's below dqio_mutex) 128 */ 129 130static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock); 131static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock); 132__cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock); 133EXPORT_SYMBOL(dq_data_lock); 134 135void __quota_error(struct super_block *sb, const char *func, 136 const char *fmt, ...) 137{ 138 va_list args; 139 140 if (printk_ratelimit()) { 141 va_start(args, fmt); 142 printk(KERN_ERR "Quota error (device %s): %s: ", 143 sb->s_id, func); 144 vprintk(fmt, args); 145 printk("\n"); 146 va_end(args); 147 } 148} 149EXPORT_SYMBOL(__quota_error); 150 151#if defined(CONFIG_QUOTA_DEBUG) || defined(CONFIG_PRINT_QUOTA_WARNING) 152static char *quotatypes[] = INITQFNAMES; 153#endif 154static struct quota_format_type *quota_formats; /* List of registered formats */ 155static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES; 156 157/* SLAB cache for dquot structures */ 158static struct kmem_cache *dquot_cachep; 159 160int register_quota_format(struct quota_format_type *fmt) 161{ 162 spin_lock(&dq_list_lock); 163 fmt->qf_next = quota_formats; 164 quota_formats = fmt; 165 spin_unlock(&dq_list_lock); 166 return 0; 167} 168EXPORT_SYMBOL(register_quota_format); 169 170void unregister_quota_format(struct quota_format_type *fmt) 171{ 172 struct quota_format_type **actqf; 173 174 spin_lock(&dq_list_lock); 175 for (actqf = "a_formats; *actqf && *actqf != fmt; 176 actqf = &(*actqf)->qf_next) 177 ; 178 if (*actqf) 179 *actqf = (*actqf)->qf_next; 180 spin_unlock(&dq_list_lock); 181} 182EXPORT_SYMBOL(unregister_quota_format); 183 184static struct quota_format_type *find_quota_format(int id) 185{ 186 struct quota_format_type *actqf; 187 188 spin_lock(&dq_list_lock); 189 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; 190 actqf = actqf->qf_next) 191 ; 192 if (!actqf || !try_module_get(actqf->qf_owner)) { 193 int qm; 194 195 spin_unlock(&dq_list_lock); 196 197 for (qm = 0; module_names[qm].qm_fmt_id && 198 module_names[qm].qm_fmt_id != id; qm++) 199 ; 200 if (!module_names[qm].qm_fmt_id || 201 request_module(module_names[qm].qm_mod_name)) 202 return NULL; 203 204 spin_lock(&dq_list_lock); 205 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; 206 actqf = actqf->qf_next) 207 ; 208 if (actqf && !try_module_get(actqf->qf_owner)) 209 actqf = NULL; 210 } 211 spin_unlock(&dq_list_lock); 212 return actqf; 213} 214 215static void put_quota_format(struct quota_format_type *fmt) 216{ 217 module_put(fmt->qf_owner); 218} 219 220/* 221 * Dquot List Management: 222 * The quota code uses three lists for dquot management: the inuse_list, 223 * free_dquots, and dquot_hash[] array. A single dquot structure may be 224 * on all three lists, depending on its current state. 225 * 226 * All dquots are placed to the end of inuse_list when first created, and this 227 * list is used for invalidate operation, which must look at every dquot. 228 * 229 * Unused dquots (dq_count == 0) are added to the free_dquots list when freed, 230 * and this list is searched whenever we need an available dquot. Dquots are 231 * removed from the list as soon as they are used again, and 232 * dqstats.free_dquots gives the number of dquots on the list. When 233 * dquot is invalidated it's completely released from memory. 234 * 235 * Dquots with a specific identity (device, type and id) are placed on 236 * one of the dquot_hash[] hash chains. The provides an efficient search 237 * mechanism to locate a specific dquot. 238 */ 239 240static LIST_HEAD(inuse_list); 241static LIST_HEAD(free_dquots); 242static unsigned int dq_hash_bits, dq_hash_mask; 243static struct hlist_head *dquot_hash; 244 245struct dqstats dqstats; 246EXPORT_SYMBOL(dqstats); 247 248static qsize_t inode_get_rsv_space(struct inode *inode); 249static void __dquot_initialize(struct inode *inode, int type); 250 251static inline unsigned int 252hashfn(const struct super_block *sb, unsigned int id, int type) 253{ 254 unsigned long tmp; 255 256 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type); 257 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask; 258} 259 260/* 261 * Following list functions expect dq_list_lock to be held 262 */ 263static inline void insert_dquot_hash(struct dquot *dquot) 264{ 265 struct hlist_head *head; 266 head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type); 267 hlist_add_head(&dquot->dq_hash, head); 268} 269 270static inline void remove_dquot_hash(struct dquot *dquot) 271{ 272 hlist_del_init(&dquot->dq_hash); 273} 274 275static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, 276 unsigned int id, int type) 277{ 278 struct hlist_node *node; 279 struct dquot *dquot; 280 281 hlist_for_each (node, dquot_hash+hashent) { 282 dquot = hlist_entry(node, struct dquot, dq_hash); 283 if (dquot->dq_sb == sb && dquot->dq_id == id && 284 dquot->dq_type == type) 285 return dquot; 286 } 287 return NULL; 288} 289 290/* Add a dquot to the tail of the free list */ 291static inline void put_dquot_last(struct dquot *dquot) 292{ 293 list_add_tail(&dquot->dq_free, &free_dquots); 294 dqstats_inc(DQST_FREE_DQUOTS); 295} 296 297static inline void remove_free_dquot(struct dquot *dquot) 298{ 299 if (list_empty(&dquot->dq_free)) 300 return; 301 list_del_init(&dquot->dq_free); 302 dqstats_dec(DQST_FREE_DQUOTS); 303} 304 305static inline void put_inuse(struct dquot *dquot) 306{ 307 /* We add to the back of inuse list so we don't have to restart 308 * when traversing this list and we block */ 309 list_add_tail(&dquot->dq_inuse, &inuse_list); 310 dqstats_inc(DQST_ALLOC_DQUOTS); 311} 312 313static inline void remove_inuse(struct dquot *dquot) 314{ 315 dqstats_dec(DQST_ALLOC_DQUOTS); 316 list_del(&dquot->dq_inuse); 317} 318/* 319 * End of list functions needing dq_list_lock 320 */ 321 322static void wait_on_dquot(struct dquot *dquot) 323{ 324 mutex_lock(&dquot->dq_lock); 325 mutex_unlock(&dquot->dq_lock); 326} 327 328static inline int dquot_dirty(struct dquot *dquot) 329{ 330 return test_bit(DQ_MOD_B, &dquot->dq_flags); 331} 332 333static inline int mark_dquot_dirty(struct dquot *dquot) 334{ 335 return dquot->dq_sb->dq_op->mark_dirty(dquot); 336} 337 338/* Mark dquot dirty in atomic manner, and return it's old dirty flag state */ 339int dquot_mark_dquot_dirty(struct dquot *dquot) 340{ 341 int ret = 1; 342 343 /* If quota is dirty already, we don't have to acquire dq_list_lock */ 344 if (test_bit(DQ_MOD_B, &dquot->dq_flags)) 345 return 1; 346 347 spin_lock(&dq_list_lock); 348 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) { 349 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)-> 350 info[dquot->dq_type].dqi_dirty_list); 351 ret = 0; 352 } 353 spin_unlock(&dq_list_lock); 354 return ret; 355} 356EXPORT_SYMBOL(dquot_mark_dquot_dirty); 357 358/* Dirtify all the dquots - this can block when journalling */ 359static inline int mark_all_dquot_dirty(struct dquot * const *dquot) 360{ 361 int ret, err, cnt; 362 363 ret = err = 0; 364 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 365 if (dquot[cnt]) 366 /* Even in case of error we have to continue */ 367 ret = mark_dquot_dirty(dquot[cnt]); 368 if (!err) 369 err = ret; 370 } 371 return err; 372} 373 374static inline void dqput_all(struct dquot **dquot) 375{ 376 unsigned int cnt; 377 378 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 379 dqput(dquot[cnt]); 380} 381 382/* This function needs dq_list_lock */ 383static inline int clear_dquot_dirty(struct dquot *dquot) 384{ 385 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) 386 return 0; 387 list_del_init(&dquot->dq_dirty); 388 return 1; 389} 390 391void mark_info_dirty(struct super_block *sb, int type) 392{ 393 set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags); 394} 395EXPORT_SYMBOL(mark_info_dirty); 396 397/* 398 * Read dquot from disk and alloc space for it 399 */ 400 401int dquot_acquire(struct dquot *dquot) 402{ 403 int ret = 0, ret2 = 0; 404 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 405 406 mutex_lock(&dquot->dq_lock); 407 mutex_lock(&dqopt->dqio_mutex); 408 if (!test_bit(DQ_READ_B, &dquot->dq_flags)) 409 ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot); 410 if (ret < 0) 411 goto out_iolock; 412 set_bit(DQ_READ_B, &dquot->dq_flags); 413 /* Instantiate dquot if needed */ 414 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) { 415 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); 416 /* Write the info if needed */ 417 if (info_dirty(&dqopt->info[dquot->dq_type])) { 418 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 419 dquot->dq_sb, dquot->dq_type); 420 } 421 if (ret < 0) 422 goto out_iolock; 423 if (ret2 < 0) { 424 ret = ret2; 425 goto out_iolock; 426 } 427 } 428 set_bit(DQ_ACTIVE_B, &dquot->dq_flags); 429out_iolock: 430 mutex_unlock(&dqopt->dqio_mutex); 431 mutex_unlock(&dquot->dq_lock); 432 return ret; 433} 434EXPORT_SYMBOL(dquot_acquire); 435 436/* 437 * Write dquot to disk 438 */ 439int dquot_commit(struct dquot *dquot) 440{ 441 int ret = 0, ret2 = 0; 442 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 443 444 mutex_lock(&dqopt->dqio_mutex); 445 spin_lock(&dq_list_lock); 446 if (!clear_dquot_dirty(dquot)) { 447 spin_unlock(&dq_list_lock); 448 goto out_sem; 449 } 450 spin_unlock(&dq_list_lock); 451 /* Inactive dquot can be only if there was error during read/init 452 * => we have better not writing it */ 453 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 454 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot); 455 if (info_dirty(&dqopt->info[dquot->dq_type])) { 456 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 457 dquot->dq_sb, dquot->dq_type); 458 } 459 if (ret >= 0) 460 ret = ret2; 461 } 462out_sem: 463 mutex_unlock(&dqopt->dqio_mutex); 464 return ret; 465} 466EXPORT_SYMBOL(dquot_commit); 467 468/* 469 * Release dquot 470 */ 471int dquot_release(struct dquot *dquot) 472{ 473 int ret = 0, ret2 = 0; 474 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 475 476 mutex_lock(&dquot->dq_lock); 477 /* Check whether we are not racing with some other dqget() */ 478 if (atomic_read(&dquot->dq_count) > 1) 479 goto out_dqlock; 480 mutex_lock(&dqopt->dqio_mutex); 481 if (dqopt->ops[dquot->dq_type]->release_dqblk) { 482 ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot); 483 /* Write the info */ 484 if (info_dirty(&dqopt->info[dquot->dq_type])) { 485 ret2 = dqopt->ops[dquot->dq_type]->write_file_info( 486 dquot->dq_sb, dquot->dq_type); 487 } 488 if (ret >= 0) 489 ret = ret2; 490 } 491 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags); 492 mutex_unlock(&dqopt->dqio_mutex); 493out_dqlock: 494 mutex_unlock(&dquot->dq_lock); 495 return ret; 496} 497EXPORT_SYMBOL(dquot_release); 498 499void dquot_destroy(struct dquot *dquot) 500{ 501 kmem_cache_free(dquot_cachep, dquot); 502} 503EXPORT_SYMBOL(dquot_destroy); 504 505static inline void do_destroy_dquot(struct dquot *dquot) 506{ 507 dquot->dq_sb->dq_op->destroy_dquot(dquot); 508} 509 510/* Invalidate all dquots on the list. Note that this function is called after 511 * quota is disabled and pointers from inodes removed so there cannot be new 512 * quota users. There can still be some users of quotas due to inodes being 513 * just deleted or pruned by prune_icache() (those are not attached to any 514 * list) or parallel quotactl call. We have to wait for such users. 515 */ 516static void invalidate_dquots(struct super_block *sb, int type) 517{ 518 struct dquot *dquot, *tmp; 519 520restart: 521 spin_lock(&dq_list_lock); 522 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) { 523 if (dquot->dq_sb != sb) 524 continue; 525 if (dquot->dq_type != type) 526 continue; 527 /* Wait for dquot users */ 528 if (atomic_read(&dquot->dq_count)) { 529 DEFINE_WAIT(wait); 530 531 atomic_inc(&dquot->dq_count); 532 prepare_to_wait(&dquot->dq_wait_unused, &wait, 533 TASK_UNINTERRUPTIBLE); 534 spin_unlock(&dq_list_lock); 535 /* Once dqput() wakes us up, we know it's time to free 536 * the dquot. 537 * IMPORTANT: we rely on the fact that there is always 538 * at most one process waiting for dquot to free. 539 * Otherwise dq_count would be > 1 and we would never 540 * wake up. 541 */ 542 if (atomic_read(&dquot->dq_count) > 1) 543 schedule(); 544 finish_wait(&dquot->dq_wait_unused, &wait); 545 dqput(dquot); 546 /* At this moment dquot() need not exist (it could be 547 * reclaimed by prune_dqcache(). Hence we must 548 * restart. */ 549 goto restart; 550 } 551 /* 552 * Quota now has no users and it has been written on last 553 * dqput() 554 */ 555 remove_dquot_hash(dquot); 556 remove_free_dquot(dquot); 557 remove_inuse(dquot); 558 do_destroy_dquot(dquot); 559 } 560 spin_unlock(&dq_list_lock); 561} 562 563/* Call callback for every active dquot on given filesystem */ 564int dquot_scan_active(struct super_block *sb, 565 int (*fn)(struct dquot *dquot, unsigned long priv), 566 unsigned long priv) 567{ 568 struct dquot *dquot, *old_dquot = NULL; 569 int ret = 0; 570 571 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 572 spin_lock(&dq_list_lock); 573 list_for_each_entry(dquot, &inuse_list, dq_inuse) { 574 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) 575 continue; 576 if (dquot->dq_sb != sb) 577 continue; 578 /* Now we have active dquot so we can just increase use count */ 579 atomic_inc(&dquot->dq_count); 580 spin_unlock(&dq_list_lock); 581 dqstats_inc(DQST_LOOKUPS); 582 dqput(old_dquot); 583 old_dquot = dquot; 584 ret = fn(dquot, priv); 585 if (ret < 0) 586 goto out; 587 spin_lock(&dq_list_lock); 588 /* We are safe to continue now because our dquot could not 589 * be moved out of the inuse list while we hold the reference */ 590 } 591 spin_unlock(&dq_list_lock); 592out: 593 dqput(old_dquot); 594 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 595 return ret; 596} 597EXPORT_SYMBOL(dquot_scan_active); 598 599int dquot_quota_sync(struct super_block *sb, int type, int wait) 600{ 601 struct list_head *dirty; 602 struct dquot *dquot; 603 struct quota_info *dqopt = sb_dqopt(sb); 604 int cnt; 605 606 mutex_lock(&dqopt->dqonoff_mutex); 607 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 608 if (type != -1 && cnt != type) 609 continue; 610 if (!sb_has_quota_active(sb, cnt)) 611 continue; 612 spin_lock(&dq_list_lock); 613 dirty = &dqopt->info[cnt].dqi_dirty_list; 614 while (!list_empty(dirty)) { 615 dquot = list_first_entry(dirty, struct dquot, 616 dq_dirty); 617 /* Dirty and inactive can be only bad dquot... */ 618 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 619 clear_dquot_dirty(dquot); 620 continue; 621 } 622 /* Now we have active dquot from which someone is 623 * holding reference so we can safely just increase 624 * use count */ 625 atomic_inc(&dquot->dq_count); 626 spin_unlock(&dq_list_lock); 627 dqstats_inc(DQST_LOOKUPS); 628 sb->dq_op->write_dquot(dquot); 629 dqput(dquot); 630 spin_lock(&dq_list_lock); 631 } 632 spin_unlock(&dq_list_lock); 633 } 634 635 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 636 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt) 637 && info_dirty(&dqopt->info[cnt])) 638 sb->dq_op->write_info(sb, cnt); 639 dqstats_inc(DQST_SYNCS); 640 mutex_unlock(&dqopt->dqonoff_mutex); 641 642 if (!wait || (sb_dqopt(sb)->flags & DQUOT_QUOTA_SYS_FILE)) 643 return 0; 644 645 /* This is not very clever (and fast) but currently I don't know about 646 * any other simple way of getting quota data to disk and we must get 647 * them there for userspace to be visible... */ 648 if (sb->s_op->sync_fs) 649 sb->s_op->sync_fs(sb, 1); 650 sync_blockdev(sb->s_bdev); 651 652 /* 653 * Now when everything is written we can discard the pagecache so 654 * that userspace sees the changes. 655 */ 656 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 657 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 658 if (type != -1 && cnt != type) 659 continue; 660 if (!sb_has_quota_active(sb, cnt)) 661 continue; 662 mutex_lock_nested(&sb_dqopt(sb)->files[cnt]->i_mutex, 663 I_MUTEX_QUOTA); 664 truncate_inode_pages(&sb_dqopt(sb)->files[cnt]->i_data, 0); 665 mutex_unlock(&sb_dqopt(sb)->files[cnt]->i_mutex); 666 } 667 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 668 669 return 0; 670} 671EXPORT_SYMBOL(dquot_quota_sync); 672 673/* Free unused dquots from cache */ 674static void prune_dqcache(int count) 675{ 676 struct list_head *head; 677 struct dquot *dquot; 678 679 head = free_dquots.prev; 680 while (head != &free_dquots && count) { 681 dquot = list_entry(head, struct dquot, dq_free); 682 remove_dquot_hash(dquot); 683 remove_free_dquot(dquot); 684 remove_inuse(dquot); 685 do_destroy_dquot(dquot); 686 count--; 687 head = free_dquots.prev; 688 } 689} 690 691/* 692 * This is called from kswapd when we think we need some 693 * more memory 694 */ 695static int shrink_dqcache_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask) 696{ 697 if (nr) { 698 spin_lock(&dq_list_lock); 699 prune_dqcache(nr); 700 spin_unlock(&dq_list_lock); 701 } 702 return ((unsigned) 703 percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS]) 704 /100) * sysctl_vfs_cache_pressure; 705} 706 707static struct shrinker dqcache_shrinker = { 708 .shrink = shrink_dqcache_memory, 709 .seeks = DEFAULT_SEEKS, 710}; 711 712/* 713 * Put reference to dquot 714 * NOTE: If you change this function please check whether dqput_blocks() works right... 715 */ 716void dqput(struct dquot *dquot) 717{ 718 int ret; 719 720 if (!dquot) 721 return; 722#ifdef CONFIG_QUOTA_DEBUG 723 if (!atomic_read(&dquot->dq_count)) { 724 quota_error(dquot->dq_sb, "trying to free free dquot of %s %d", 725 quotatypes[dquot->dq_type], dquot->dq_id); 726 BUG(); 727 } 728#endif 729 dqstats_inc(DQST_DROPS); 730we_slept: 731 spin_lock(&dq_list_lock); 732 if (atomic_read(&dquot->dq_count) > 1) { 733 /* We have more than one user... nothing to do */ 734 atomic_dec(&dquot->dq_count); 735 /* Releasing dquot during quotaoff phase? */ 736 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) && 737 atomic_read(&dquot->dq_count) == 1) 738 wake_up(&dquot->dq_wait_unused); 739 spin_unlock(&dq_list_lock); 740 return; 741 } 742 /* Need to release dquot? */ 743 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) { 744 spin_unlock(&dq_list_lock); 745 /* Commit dquot before releasing */ 746 ret = dquot->dq_sb->dq_op->write_dquot(dquot); 747 if (ret < 0) { 748 quota_error(dquot->dq_sb, "Can't write quota structure" 749 " (error %d). Quota may get out of sync!", 750 ret); 751 /* 752 * We clear dirty bit anyway, so that we avoid 753 * infinite loop here 754 */ 755 spin_lock(&dq_list_lock); 756 clear_dquot_dirty(dquot); 757 spin_unlock(&dq_list_lock); 758 } 759 goto we_slept; 760 } 761 /* Clear flag in case dquot was inactive (something bad happened) */ 762 clear_dquot_dirty(dquot); 763 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { 764 spin_unlock(&dq_list_lock); 765 dquot->dq_sb->dq_op->release_dquot(dquot); 766 goto we_slept; 767 } 768 atomic_dec(&dquot->dq_count); 769#ifdef CONFIG_QUOTA_DEBUG 770 /* sanity check */ 771 BUG_ON(!list_empty(&dquot->dq_free)); 772#endif 773 put_dquot_last(dquot); 774 spin_unlock(&dq_list_lock); 775} 776EXPORT_SYMBOL(dqput); 777 778struct dquot *dquot_alloc(struct super_block *sb, int type) 779{ 780 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); 781} 782EXPORT_SYMBOL(dquot_alloc); 783 784static struct dquot *get_empty_dquot(struct super_block *sb, int type) 785{ 786 struct dquot *dquot; 787 788 dquot = sb->dq_op->alloc_dquot(sb, type); 789 if(!dquot) 790 return NULL; 791 792 mutex_init(&dquot->dq_lock); 793 INIT_LIST_HEAD(&dquot->dq_free); 794 INIT_LIST_HEAD(&dquot->dq_inuse); 795 INIT_HLIST_NODE(&dquot->dq_hash); 796 INIT_LIST_HEAD(&dquot->dq_dirty); 797 init_waitqueue_head(&dquot->dq_wait_unused); 798 dquot->dq_sb = sb; 799 dquot->dq_type = type; 800 atomic_set(&dquot->dq_count, 1); 801 802 return dquot; 803} 804 805/* 806 * Get reference to dquot 807 * 808 * Locking is slightly tricky here. We are guarded from parallel quotaoff() 809 * destroying our dquot by: 810 * a) checking for quota flags under dq_list_lock and 811 * b) getting a reference to dquot before we release dq_list_lock 812 */ 813struct dquot *dqget(struct super_block *sb, unsigned int id, int type) 814{ 815 unsigned int hashent = hashfn(sb, id, type); 816 struct dquot *dquot = NULL, *empty = NULL; 817 818 if (!sb_has_quota_active(sb, type)) 819 return NULL; 820we_slept: 821 spin_lock(&dq_list_lock); 822 spin_lock(&dq_state_lock); 823 if (!sb_has_quota_active(sb, type)) { 824 spin_unlock(&dq_state_lock); 825 spin_unlock(&dq_list_lock); 826 goto out; 827 } 828 spin_unlock(&dq_state_lock); 829 830 dquot = find_dquot(hashent, sb, id, type); 831 if (!dquot) { 832 if (!empty) { 833 spin_unlock(&dq_list_lock); 834 empty = get_empty_dquot(sb, type); 835 if (!empty) 836 schedule(); /* Try to wait for a moment... */ 837 goto we_slept; 838 } 839 dquot = empty; 840 empty = NULL; 841 dquot->dq_id = id; 842 /* all dquots go on the inuse_list */ 843 put_inuse(dquot); 844 /* hash it first so it can be found */ 845 insert_dquot_hash(dquot); 846 spin_unlock(&dq_list_lock); 847 dqstats_inc(DQST_LOOKUPS); 848 } else { 849 if (!atomic_read(&dquot->dq_count)) 850 remove_free_dquot(dquot); 851 atomic_inc(&dquot->dq_count); 852 spin_unlock(&dq_list_lock); 853 dqstats_inc(DQST_CACHE_HITS); 854 dqstats_inc(DQST_LOOKUPS); 855 } 856 /* Wait for dq_lock - after this we know that either dquot_release() is 857 * already finished or it will be canceled due to dq_count > 1 test */ 858 wait_on_dquot(dquot); 859 /* Read the dquot / allocate space in quota file */ 860 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && 861 sb->dq_op->acquire_dquot(dquot) < 0) { 862 dqput(dquot); 863 dquot = NULL; 864 goto out; 865 } 866#ifdef CONFIG_QUOTA_DEBUG 867 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ 868#endif 869out: 870 if (empty) 871 do_destroy_dquot(empty); 872 873 return dquot; 874} 875EXPORT_SYMBOL(dqget); 876 877static int dqinit_needed(struct inode *inode, int type) 878{ 879 int cnt; 880 881 if (IS_NOQUOTA(inode)) 882 return 0; 883 if (type != -1) 884 return !inode->i_dquot[type]; 885 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 886 if (!inode->i_dquot[cnt]) 887 return 1; 888 return 0; 889} 890 891/* This routine is guarded by dqonoff_mutex mutex */ 892static void add_dquot_ref(struct super_block *sb, int type) 893{ 894 struct inode *inode, *old_inode = NULL; 895#ifdef CONFIG_QUOTA_DEBUG 896 int reserved = 0; 897#endif 898 899 spin_lock(&inode_lock); 900 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 901 if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) 902 continue; 903#ifdef CONFIG_QUOTA_DEBUG 904 if (unlikely(inode_get_rsv_space(inode) > 0)) 905 reserved = 1; 906#endif 907 if (!atomic_read(&inode->i_writecount)) 908 continue; 909 if (!dqinit_needed(inode, type)) 910 continue; 911 912 __iget(inode); 913 spin_unlock(&inode_lock); 914 915 iput(old_inode); 916 __dquot_initialize(inode, type); 917 /* We hold a reference to 'inode' so it couldn't have been 918 * removed from s_inodes list while we dropped the inode_lock. 919 * We cannot iput the inode now as we can be holding the last 920 * reference and we cannot iput it under inode_lock. So we 921 * keep the reference and iput it later. */ 922 old_inode = inode; 923 spin_lock(&inode_lock); 924 } 925 spin_unlock(&inode_lock); 926 iput(old_inode); 927 928#ifdef CONFIG_QUOTA_DEBUG 929 if (reserved) { 930 quota_error(sb, "Writes happened before quota was turned on " 931 "thus quota information is probably inconsistent. " 932 "Please run quotacheck(8)"); 933 } 934#endif 935} 936 937/* 938 * Return 0 if dqput() won't block. 939 * (note that 1 doesn't necessarily mean blocking) 940 */ 941static inline int dqput_blocks(struct dquot *dquot) 942{ 943 if (atomic_read(&dquot->dq_count) <= 1) 944 return 1; 945 return 0; 946} 947 948/* 949 * Remove references to dquots from inode and add dquot to list for freeing 950 * if we have the last referece to dquot 951 * We can't race with anybody because we hold dqptr_sem for writing... 952 */ 953static int remove_inode_dquot_ref(struct inode *inode, int type, 954 struct list_head *tofree_head) 955{ 956 struct dquot *dquot = inode->i_dquot[type]; 957 958 inode->i_dquot[type] = NULL; 959 if (dquot) { 960 if (dqput_blocks(dquot)) { 961#ifdef CONFIG_QUOTA_DEBUG 962 if (atomic_read(&dquot->dq_count) != 1) 963 quota_error(inode->i_sb, "Adding dquot with " 964 "dq_count %d to dispose list", 965 atomic_read(&dquot->dq_count)); 966#endif 967 spin_lock(&dq_list_lock); 968 /* As dquot must have currently users it can't be on 969 * the free list... */ 970 list_add(&dquot->dq_free, tofree_head); 971 spin_unlock(&dq_list_lock); 972 return 1; 973 } 974 else 975 dqput(dquot); /* We have guaranteed we won't block */ 976 } 977 return 0; 978} 979 980/* 981 * Free list of dquots 982 * Dquots are removed from inodes and no new references can be got so we are 983 * the only ones holding reference 984 */ 985static void put_dquot_list(struct list_head *tofree_head) 986{ 987 struct list_head *act_head; 988 struct dquot *dquot; 989 990 act_head = tofree_head->next; 991 while (act_head != tofree_head) { 992 dquot = list_entry(act_head, struct dquot, dq_free); 993 act_head = act_head->next; 994 /* Remove dquot from the list so we won't have problems... */ 995 list_del_init(&dquot->dq_free); 996 dqput(dquot); 997 } 998} 999 1000static void remove_dquot_ref(struct super_block *sb, int type, 1001 struct list_head *tofree_head) 1002{ 1003 struct inode *inode; 1004 int reserved = 0; 1005 1006 spin_lock(&inode_lock); 1007 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { 1008 /* 1009 * We have to scan also I_NEW inodes because they can already 1010 * have quota pointer initialized. Luckily, we need to touch 1011 * only quota pointers and these have separate locking 1012 * (dqptr_sem). 1013 */ 1014 if (!IS_NOQUOTA(inode)) { 1015 if (unlikely(inode_get_rsv_space(inode) > 0)) 1016 reserved = 1; 1017 remove_inode_dquot_ref(inode, type, tofree_head); 1018 } 1019 } 1020 spin_unlock(&inode_lock); 1021#ifdef CONFIG_QUOTA_DEBUG 1022 if (reserved) { 1023 printk(KERN_WARNING "VFS (%s): Writes happened after quota" 1024 " was disabled thus quota information is probably " 1025 "inconsistent. Please run quotacheck(8).\n", sb->s_id); 1026 } 1027#endif 1028} 1029 1030/* Gather all references from inodes and drop them */ 1031static void drop_dquot_ref(struct super_block *sb, int type) 1032{ 1033 LIST_HEAD(tofree_head); 1034 1035 if (sb->dq_op) { 1036 down_write(&sb_dqopt(sb)->dqptr_sem); 1037 remove_dquot_ref(sb, type, &tofree_head); 1038 up_write(&sb_dqopt(sb)->dqptr_sem); 1039 put_dquot_list(&tofree_head); 1040 } 1041} 1042 1043static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) 1044{ 1045 dquot->dq_dqb.dqb_curinodes += number; 1046} 1047 1048static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) 1049{ 1050 dquot->dq_dqb.dqb_curspace += number; 1051} 1052 1053static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 1054{ 1055 dquot->dq_dqb.dqb_rsvspace += number; 1056} 1057 1058/* 1059 * Claim reserved quota space 1060 */ 1061static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number) 1062{ 1063 if (dquot->dq_dqb.dqb_rsvspace < number) { 1064 WARN_ON_ONCE(1); 1065 number = dquot->dq_dqb.dqb_rsvspace; 1066 } 1067 dquot->dq_dqb.dqb_curspace += number; 1068 dquot->dq_dqb.dqb_rsvspace -= number; 1069} 1070 1071static inline 1072void dquot_free_reserved_space(struct dquot *dquot, qsize_t number) 1073{ 1074 if (dquot->dq_dqb.dqb_rsvspace >= number) 1075 dquot->dq_dqb.dqb_rsvspace -= number; 1076 else { 1077 WARN_ON_ONCE(1); 1078 dquot->dq_dqb.dqb_rsvspace = 0; 1079 } 1080} 1081 1082static void dquot_decr_inodes(struct dquot *dquot, qsize_t number) 1083{ 1084 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1085 dquot->dq_dqb.dqb_curinodes >= number) 1086 dquot->dq_dqb.dqb_curinodes -= number; 1087 else 1088 dquot->dq_dqb.dqb_curinodes = 0; 1089 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) 1090 dquot->dq_dqb.dqb_itime = (time_t) 0; 1091 clear_bit(DQ_INODES_B, &dquot->dq_flags); 1092} 1093 1094static void dquot_decr_space(struct dquot *dquot, qsize_t number) 1095{ 1096 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || 1097 dquot->dq_dqb.dqb_curspace >= number) 1098 dquot->dq_dqb.dqb_curspace -= number; 1099 else 1100 dquot->dq_dqb.dqb_curspace = 0; 1101 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1102 dquot->dq_dqb.dqb_btime = (time_t) 0; 1103 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 1104} 1105 1106static int warning_issued(struct dquot *dquot, const int warntype) 1107{ 1108 int flag = (warntype == QUOTA_NL_BHARDWARN || 1109 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B : 1110 ((warntype == QUOTA_NL_IHARDWARN || 1111 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0); 1112 1113 if (!flag) 1114 return 0; 1115 return test_and_set_bit(flag, &dquot->dq_flags); 1116} 1117 1118#ifdef CONFIG_PRINT_QUOTA_WARNING 1119static int flag_print_warnings = 1; 1120 1121static int need_print_warning(struct dquot *dquot) 1122{ 1123 if (!flag_print_warnings) 1124 return 0; 1125 1126 switch (dquot->dq_type) { 1127 case USRQUOTA: 1128 return current_fsuid() == dquot->dq_id; 1129 case GRPQUOTA: 1130 return in_group_p(dquot->dq_id); 1131 } 1132 return 0; 1133} 1134 1135/* Print warning to user which exceeded quota */ 1136static void print_warning(struct dquot *dquot, const int warntype) 1137{ 1138 char *msg = NULL; 1139 struct tty_struct *tty; 1140 1141 if (warntype == QUOTA_NL_IHARDBELOW || 1142 warntype == QUOTA_NL_ISOFTBELOW || 1143 warntype == QUOTA_NL_BHARDBELOW || 1144 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot)) 1145 return; 1146 1147 tty = get_current_tty(); 1148 if (!tty) 1149 return; 1150 tty_write_message(tty, dquot->dq_sb->s_id); 1151 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN) 1152 tty_write_message(tty, ": warning, "); 1153 else 1154 tty_write_message(tty, ": write failed, "); 1155 tty_write_message(tty, quotatypes[dquot->dq_type]); 1156 switch (warntype) { 1157 case QUOTA_NL_IHARDWARN: 1158 msg = " file limit reached.\r\n"; 1159 break; 1160 case QUOTA_NL_ISOFTLONGWARN: 1161 msg = " file quota exceeded too long.\r\n"; 1162 break; 1163 case QUOTA_NL_ISOFTWARN: 1164 msg = " file quota exceeded.\r\n"; 1165 break; 1166 case QUOTA_NL_BHARDWARN: 1167 msg = " block limit reached.\r\n"; 1168 break; 1169 case QUOTA_NL_BSOFTLONGWARN: 1170 msg = " block quota exceeded too long.\r\n"; 1171 break; 1172 case QUOTA_NL_BSOFTWARN: 1173 msg = " block quota exceeded.\r\n"; 1174 break; 1175 } 1176 tty_write_message(tty, msg); 1177 tty_kref_put(tty); 1178} 1179#endif 1180 1181/* 1182 * Write warnings to the console and send warning messages over netlink. 1183 * 1184 * Note that this function can sleep. 1185 */ 1186static void flush_warnings(struct dquot *const *dquots, char *warntype) 1187{ 1188 struct dquot *dq; 1189 int i; 1190 1191 for (i = 0; i < MAXQUOTAS; i++) { 1192 dq = dquots[i]; 1193 if (dq && warntype[i] != QUOTA_NL_NOWARN && 1194 !warning_issued(dq, warntype[i])) { 1195#ifdef CONFIG_PRINT_QUOTA_WARNING 1196 print_warning(dq, warntype[i]); 1197#endif 1198 quota_send_warning(dq->dq_type, dq->dq_id, 1199 dq->dq_sb->s_dev, warntype[i]); 1200 } 1201 } 1202} 1203 1204static int ignore_hardlimit(struct dquot *dquot) 1205{ 1206 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 1207 1208 return capable(CAP_SYS_RESOURCE) && 1209 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || 1210 !(info->dqi_flags & V1_DQF_RSQUASH)); 1211} 1212 1213/* needs dq_data_lock */ 1214static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) 1215{ 1216 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes; 1217 1218 *warntype = QUOTA_NL_NOWARN; 1219 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || 1220 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1221 return 0; 1222 1223 if (dquot->dq_dqb.dqb_ihardlimit && 1224 newinodes > dquot->dq_dqb.dqb_ihardlimit && 1225 !ignore_hardlimit(dquot)) { 1226 *warntype = QUOTA_NL_IHARDWARN; 1227 return -EDQUOT; 1228 } 1229 1230 if (dquot->dq_dqb.dqb_isoftlimit && 1231 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1232 dquot->dq_dqb.dqb_itime && 1233 get_seconds() >= dquot->dq_dqb.dqb_itime && 1234 !ignore_hardlimit(dquot)) { 1235 *warntype = QUOTA_NL_ISOFTLONGWARN; 1236 return -EDQUOT; 1237 } 1238 1239 if (dquot->dq_dqb.dqb_isoftlimit && 1240 newinodes > dquot->dq_dqb.dqb_isoftlimit && 1241 dquot->dq_dqb.dqb_itime == 0) { 1242 *warntype = QUOTA_NL_ISOFTWARN; 1243 dquot->dq_dqb.dqb_itime = get_seconds() + 1244 sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace; 1245 } 1246 1247 return 0; 1248} 1249 1250/* needs dq_data_lock */ 1251static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) 1252{ 1253 qsize_t tspace; 1254 struct super_block *sb = dquot->dq_sb; 1255 1256 *warntype = QUOTA_NL_NOWARN; 1257 if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) || 1258 test_bit(DQ_FAKE_B, &dquot->dq_flags)) 1259 return 0; 1260 1261 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace 1262 + space; 1263 1264 if (dquot->dq_dqb.dqb_bhardlimit && 1265 tspace > dquot->dq_dqb.dqb_bhardlimit && 1266 !ignore_hardlimit(dquot)) { 1267 if (!prealloc) 1268 *warntype = QUOTA_NL_BHARDWARN; 1269 return -EDQUOT; 1270 } 1271 1272 if (dquot->dq_dqb.dqb_bsoftlimit && 1273 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1274 dquot->dq_dqb.dqb_btime && 1275 get_seconds() >= dquot->dq_dqb.dqb_btime && 1276 !ignore_hardlimit(dquot)) { 1277 if (!prealloc) 1278 *warntype = QUOTA_NL_BSOFTLONGWARN; 1279 return -EDQUOT; 1280 } 1281 1282 if (dquot->dq_dqb.dqb_bsoftlimit && 1283 tspace > dquot->dq_dqb.dqb_bsoftlimit && 1284 dquot->dq_dqb.dqb_btime == 0) { 1285 if (!prealloc) { 1286 *warntype = QUOTA_NL_BSOFTWARN; 1287 dquot->dq_dqb.dqb_btime = get_seconds() + 1288 sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace; 1289 } 1290 else 1291 /* 1292 * We don't allow preallocation to exceed softlimit so exceeding will 1293 * be always printed 1294 */ 1295 return -EDQUOT; 1296 } 1297 1298 return 0; 1299} 1300 1301static int info_idq_free(struct dquot *dquot, qsize_t inodes) 1302{ 1303 qsize_t newinodes; 1304 1305 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1306 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || 1307 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type)) 1308 return QUOTA_NL_NOWARN; 1309 1310 newinodes = dquot->dq_dqb.dqb_curinodes - inodes; 1311 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit) 1312 return QUOTA_NL_ISOFTBELOW; 1313 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit && 1314 newinodes < dquot->dq_dqb.dqb_ihardlimit) 1315 return QUOTA_NL_IHARDBELOW; 1316 return QUOTA_NL_NOWARN; 1317} 1318 1319static int info_bdq_free(struct dquot *dquot, qsize_t space) 1320{ 1321 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || 1322 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) 1323 return QUOTA_NL_NOWARN; 1324 1325 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) 1326 return QUOTA_NL_BSOFTBELOW; 1327 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && 1328 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) 1329 return QUOTA_NL_BHARDBELOW; 1330 return QUOTA_NL_NOWARN; 1331} 1332 1333static int dquot_active(const struct inode *inode) 1334{ 1335 struct super_block *sb = inode->i_sb; 1336 1337 if (IS_NOQUOTA(inode)) 1338 return 0; 1339 return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb); 1340} 1341 1342/* 1343 * Initialize quota pointers in inode 1344 * 1345 * We do things in a bit complicated way but by that we avoid calling 1346 * dqget() and thus filesystem callbacks under dqptr_sem. 1347 * 1348 * It is better to call this function outside of any transaction as it 1349 * might need a lot of space in journal for dquot structure allocation. 1350 */ 1351static void __dquot_initialize(struct inode *inode, int type) 1352{ 1353 unsigned int id = 0; 1354 int cnt; 1355 struct dquot *got[MAXQUOTAS]; 1356 struct super_block *sb = inode->i_sb; 1357 qsize_t rsv; 1358 1359 /* First test before acquiring mutex - solves deadlocks when we 1360 * re-enter the quota code and are already holding the mutex */ 1361 if (!dquot_active(inode)) 1362 return; 1363 1364 /* First get references to structures we might need. */ 1365 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1366 got[cnt] = NULL; 1367 if (type != -1 && cnt != type) 1368 continue; 1369 switch (cnt) { 1370 case USRQUOTA: 1371 id = inode->i_uid; 1372 break; 1373 case GRPQUOTA: 1374 id = inode->i_gid; 1375 break; 1376 } 1377 got[cnt] = dqget(sb, id, cnt); 1378 } 1379 1380 down_write(&sb_dqopt(sb)->dqptr_sem); 1381 if (IS_NOQUOTA(inode)) 1382 goto out_err; 1383 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1384 if (type != -1 && cnt != type) 1385 continue; 1386 /* Avoid races with quotaoff() */ 1387 if (!sb_has_quota_active(sb, cnt)) 1388 continue; 1389 if (!inode->i_dquot[cnt]) { 1390 inode->i_dquot[cnt] = got[cnt]; 1391 got[cnt] = NULL; 1392 /* 1393 * Make quota reservation system happy if someone 1394 * did a write before quota was turned on 1395 */ 1396 rsv = inode_get_rsv_space(inode); 1397 if (unlikely(rsv)) 1398 dquot_resv_space(inode->i_dquot[cnt], rsv); 1399 } 1400 } 1401out_err: 1402 up_write(&sb_dqopt(sb)->dqptr_sem); 1403 /* Drop unused references */ 1404 dqput_all(got); 1405} 1406 1407void dquot_initialize(struct inode *inode) 1408{ 1409 __dquot_initialize(inode, -1); 1410} 1411EXPORT_SYMBOL(dquot_initialize); 1412 1413/* 1414 * Release all quotas referenced by inode 1415 */ 1416static void __dquot_drop(struct inode *inode) 1417{ 1418 int cnt; 1419 struct dquot *put[MAXQUOTAS]; 1420 1421 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1422 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1423 put[cnt] = inode->i_dquot[cnt]; 1424 inode->i_dquot[cnt] = NULL; 1425 } 1426 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1427 dqput_all(put); 1428} 1429 1430void dquot_drop(struct inode *inode) 1431{ 1432 int cnt; 1433 1434 if (IS_NOQUOTA(inode)) 1435 return; 1436 1437 /* 1438 * Test before calling to rule out calls from proc and such 1439 * where we are not allowed to block. Note that this is 1440 * actually reliable test even without the lock - the caller 1441 * must assure that nobody can come after the DQUOT_DROP and 1442 * add quota pointers back anyway. 1443 */ 1444 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1445 if (inode->i_dquot[cnt]) 1446 break; 1447 } 1448 1449 if (cnt < MAXQUOTAS) 1450 __dquot_drop(inode); 1451} 1452EXPORT_SYMBOL(dquot_drop); 1453 1454/* 1455 * inode_reserved_space is managed internally by quota, and protected by 1456 * i_lock similar to i_blocks+i_bytes. 1457 */ 1458static qsize_t *inode_reserved_space(struct inode * inode) 1459{ 1460 /* Filesystem must explicitly define it's own method in order to use 1461 * quota reservation interface */ 1462 BUG_ON(!inode->i_sb->dq_op->get_reserved_space); 1463 return inode->i_sb->dq_op->get_reserved_space(inode); 1464} 1465 1466void inode_add_rsv_space(struct inode *inode, qsize_t number) 1467{ 1468 spin_lock(&inode->i_lock); 1469 *inode_reserved_space(inode) += number; 1470 spin_unlock(&inode->i_lock); 1471} 1472EXPORT_SYMBOL(inode_add_rsv_space); 1473 1474void inode_claim_rsv_space(struct inode *inode, qsize_t number) 1475{ 1476 spin_lock(&inode->i_lock); 1477 *inode_reserved_space(inode) -= number; 1478 __inode_add_bytes(inode, number); 1479 spin_unlock(&inode->i_lock); 1480} 1481EXPORT_SYMBOL(inode_claim_rsv_space); 1482 1483void inode_sub_rsv_space(struct inode *inode, qsize_t number) 1484{ 1485 spin_lock(&inode->i_lock); 1486 *inode_reserved_space(inode) -= number; 1487 spin_unlock(&inode->i_lock); 1488} 1489EXPORT_SYMBOL(inode_sub_rsv_space); 1490 1491static qsize_t inode_get_rsv_space(struct inode *inode) 1492{ 1493 qsize_t ret; 1494 1495 if (!inode->i_sb->dq_op->get_reserved_space) 1496 return 0; 1497 spin_lock(&inode->i_lock); 1498 ret = *inode_reserved_space(inode); 1499 spin_unlock(&inode->i_lock); 1500 return ret; 1501} 1502 1503static void inode_incr_space(struct inode *inode, qsize_t number, 1504 int reserve) 1505{ 1506 if (reserve) 1507 inode_add_rsv_space(inode, number); 1508 else 1509 inode_add_bytes(inode, number); 1510} 1511 1512static void inode_decr_space(struct inode *inode, qsize_t number, int reserve) 1513{ 1514 if (reserve) 1515 inode_sub_rsv_space(inode, number); 1516 else 1517 inode_sub_bytes(inode, number); 1518} 1519 1520/* 1521 * This functions updates i_blocks+i_bytes fields and quota information 1522 * (together with appropriate checks). 1523 * 1524 * NOTE: We absolutely rely on the fact that caller dirties the inode 1525 * (usually helpers in quotaops.h care about this) and holds a handle for 1526 * the current transaction so that dquot write and inode write go into the 1527 * same transaction. 1528 */ 1529 1530/* 1531 * This operation can block, but only after everything is updated 1532 */ 1533int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags) 1534{ 1535 int cnt, ret = 0; 1536 char warntype[MAXQUOTAS]; 1537 int warn = flags & DQUOT_SPACE_WARN; 1538 int reserve = flags & DQUOT_SPACE_RESERVE; 1539 int nofail = flags & DQUOT_SPACE_NOFAIL; 1540 1541 /* 1542 * First test before acquiring mutex - solves deadlocks when we 1543 * re-enter the quota code and are already holding the mutex 1544 */ 1545 if (!dquot_active(inode)) { 1546 inode_incr_space(inode, number, reserve); 1547 goto out; 1548 } 1549 1550 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1551 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1552 warntype[cnt] = QUOTA_NL_NOWARN; 1553 1554 spin_lock(&dq_data_lock); 1555 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1556 if (!inode->i_dquot[cnt]) 1557 continue; 1558 ret = check_bdq(inode->i_dquot[cnt], number, !warn, 1559 warntype+cnt); 1560 if (ret && !nofail) { 1561 spin_unlock(&dq_data_lock); 1562 goto out_flush_warn; 1563 } 1564 } 1565 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1566 if (!inode->i_dquot[cnt]) 1567 continue; 1568 if (reserve) 1569 dquot_resv_space(inode->i_dquot[cnt], number); 1570 else 1571 dquot_incr_space(inode->i_dquot[cnt], number); 1572 } 1573 inode_incr_space(inode, number, reserve); 1574 spin_unlock(&dq_data_lock); 1575 1576 if (reserve) 1577 goto out_flush_warn; 1578 mark_all_dquot_dirty(inode->i_dquot); 1579out_flush_warn: 1580 flush_warnings(inode->i_dquot, warntype); 1581 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1582out: 1583 return ret; 1584} 1585EXPORT_SYMBOL(__dquot_alloc_space); 1586 1587/* 1588 * This operation can block, but only after everything is updated 1589 */ 1590int dquot_alloc_inode(const struct inode *inode) 1591{ 1592 int cnt, ret = 0; 1593 char warntype[MAXQUOTAS]; 1594 1595 /* First test before acquiring mutex - solves deadlocks when we 1596 * re-enter the quota code and are already holding the mutex */ 1597 if (!dquot_active(inode)) 1598 return 0; 1599 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1600 warntype[cnt] = QUOTA_NL_NOWARN; 1601 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1602 spin_lock(&dq_data_lock); 1603 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1604 if (!inode->i_dquot[cnt]) 1605 continue; 1606 ret = check_idq(inode->i_dquot[cnt], 1, warntype + cnt); 1607 if (ret) 1608 goto warn_put_all; 1609 } 1610 1611 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1612 if (!inode->i_dquot[cnt]) 1613 continue; 1614 dquot_incr_inodes(inode->i_dquot[cnt], 1); 1615 } 1616 1617warn_put_all: 1618 spin_unlock(&dq_data_lock); 1619 if (ret == 0) 1620 mark_all_dquot_dirty(inode->i_dquot); 1621 flush_warnings(inode->i_dquot, warntype); 1622 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1623 return ret; 1624} 1625EXPORT_SYMBOL(dquot_alloc_inode); 1626 1627/* 1628 * Convert in-memory reserved quotas to real consumed quotas 1629 */ 1630int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 1631{ 1632 int cnt; 1633 1634 if (!dquot_active(inode)) { 1635 inode_claim_rsv_space(inode, number); 1636 return 0; 1637 } 1638 1639 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1640 spin_lock(&dq_data_lock); 1641 /* Claim reserved quotas to allocated quotas */ 1642 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1643 if (inode->i_dquot[cnt]) 1644 dquot_claim_reserved_space(inode->i_dquot[cnt], 1645 number); 1646 } 1647 /* Update inode bytes */ 1648 inode_claim_rsv_space(inode, number); 1649 spin_unlock(&dq_data_lock); 1650 mark_all_dquot_dirty(inode->i_dquot); 1651 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1652 return 0; 1653} 1654EXPORT_SYMBOL(dquot_claim_space_nodirty); 1655 1656/* 1657 * This operation can block, but only after everything is updated 1658 */ 1659void __dquot_free_space(struct inode *inode, qsize_t number, int flags) 1660{ 1661 unsigned int cnt; 1662 char warntype[MAXQUOTAS]; 1663 int reserve = flags & DQUOT_SPACE_RESERVE; 1664 1665 /* First test before acquiring mutex - solves deadlocks when we 1666 * re-enter the quota code and are already holding the mutex */ 1667 if (!dquot_active(inode)) { 1668 inode_decr_space(inode, number, reserve); 1669 return; 1670 } 1671 1672 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1673 spin_lock(&dq_data_lock); 1674 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1675 if (!inode->i_dquot[cnt]) 1676 continue; 1677 warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number); 1678 if (reserve) 1679 dquot_free_reserved_space(inode->i_dquot[cnt], number); 1680 else 1681 dquot_decr_space(inode->i_dquot[cnt], number); 1682 } 1683 inode_decr_space(inode, number, reserve); 1684 spin_unlock(&dq_data_lock); 1685 1686 if (reserve) 1687 goto out_unlock; 1688 mark_all_dquot_dirty(inode->i_dquot); 1689out_unlock: 1690 flush_warnings(inode->i_dquot, warntype); 1691 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1692} 1693EXPORT_SYMBOL(__dquot_free_space); 1694 1695/* 1696 * This operation can block, but only after everything is updated 1697 */ 1698void dquot_free_inode(const struct inode *inode) 1699{ 1700 unsigned int cnt; 1701 char warntype[MAXQUOTAS]; 1702 1703 /* First test before acquiring mutex - solves deadlocks when we 1704 * re-enter the quota code and are already holding the mutex */ 1705 if (!dquot_active(inode)) 1706 return; 1707 1708 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1709 spin_lock(&dq_data_lock); 1710 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1711 if (!inode->i_dquot[cnt]) 1712 continue; 1713 warntype[cnt] = info_idq_free(inode->i_dquot[cnt], 1); 1714 dquot_decr_inodes(inode->i_dquot[cnt], 1); 1715 } 1716 spin_unlock(&dq_data_lock); 1717 mark_all_dquot_dirty(inode->i_dquot); 1718 flush_warnings(inode->i_dquot, warntype); 1719 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem); 1720} 1721EXPORT_SYMBOL(dquot_free_inode); 1722 1723/* 1724 * Transfer the number of inode and blocks from one diskquota to an other. 1725 * On success, dquot references in transfer_to are consumed and references 1726 * to original dquots that need to be released are placed there. On failure, 1727 * references are kept untouched. 1728 * 1729 * This operation can block, but only after everything is updated 1730 * A transaction must be started when entering this function. 1731 * 1732 */ 1733int __dquot_transfer(struct inode *inode, struct dquot **transfer_to) 1734{ 1735 qsize_t space, cur_space; 1736 qsize_t rsv_space = 0; 1737 struct dquot *transfer_from[MAXQUOTAS] = {}; 1738 int cnt, ret = 0; 1739 char warntype_to[MAXQUOTAS]; 1740 char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS]; 1741 1742 /* First test before acquiring mutex - solves deadlocks when we 1743 * re-enter the quota code and are already holding the mutex */ 1744 if (IS_NOQUOTA(inode)) 1745 return 0; 1746 /* Initialize the arrays */ 1747 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1748 warntype_to[cnt] = QUOTA_NL_NOWARN; 1749 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1750 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ 1751 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1752 return 0; 1753 } 1754 spin_lock(&dq_data_lock); 1755 cur_space = inode_get_bytes(inode); 1756 rsv_space = inode_get_rsv_space(inode); 1757 space = cur_space + rsv_space; 1758 /* Build the transfer_from list and check the limits */ 1759 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1760 if (!transfer_to[cnt]) 1761 continue; 1762 transfer_from[cnt] = inode->i_dquot[cnt]; 1763 ret = check_idq(transfer_to[cnt], 1, warntype_to + cnt); 1764 if (ret) 1765 goto over_quota; 1766 ret = check_bdq(transfer_to[cnt], space, 0, warntype_to + cnt); 1767 if (ret) 1768 goto over_quota; 1769 } 1770 1771 /* 1772 * Finally perform the needed transfer from transfer_from to transfer_to 1773 */ 1774 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1775 /* 1776 * Skip changes for same uid or gid or for turned off quota-type. 1777 */ 1778 if (!transfer_to[cnt]) 1779 continue; 1780 1781 /* Due to IO error we might not have transfer_from[] structure */ 1782 if (transfer_from[cnt]) { 1783 warntype_from_inodes[cnt] = 1784 info_idq_free(transfer_from[cnt], 1); 1785 warntype_from_space[cnt] = 1786 info_bdq_free(transfer_from[cnt], space); 1787 dquot_decr_inodes(transfer_from[cnt], 1); 1788 dquot_decr_space(transfer_from[cnt], cur_space); 1789 dquot_free_reserved_space(transfer_from[cnt], 1790 rsv_space); 1791 } 1792 1793 dquot_incr_inodes(transfer_to[cnt], 1); 1794 dquot_incr_space(transfer_to[cnt], cur_space); 1795 dquot_resv_space(transfer_to[cnt], rsv_space); 1796 1797 inode->i_dquot[cnt] = transfer_to[cnt]; 1798 } 1799 spin_unlock(&dq_data_lock); 1800 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1801 1802 mark_all_dquot_dirty(transfer_from); 1803 mark_all_dquot_dirty(transfer_to); 1804 /* Pass back references to put */ 1805 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1806 transfer_to[cnt] = transfer_from[cnt]; 1807warn: 1808 flush_warnings(transfer_to, warntype_to); 1809 flush_warnings(transfer_from, warntype_from_inodes); 1810 flush_warnings(transfer_from, warntype_from_space); 1811 return ret; 1812over_quota: 1813 spin_unlock(&dq_data_lock); 1814 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); 1815 goto warn; 1816} 1817EXPORT_SYMBOL(__dquot_transfer); 1818 1819/* Wrapper for transferring ownership of an inode for uid/gid only 1820 * Called from FSXXX_setattr() 1821 */ 1822int dquot_transfer(struct inode *inode, struct iattr *iattr) 1823{ 1824 struct dquot *transfer_to[MAXQUOTAS] = {}; 1825 struct super_block *sb = inode->i_sb; 1826 int ret; 1827 1828 if (!dquot_active(inode)) 1829 return 0; 1830 1831 if (iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) 1832 transfer_to[USRQUOTA] = dqget(sb, iattr->ia_uid, USRQUOTA); 1833 if (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid) 1834 transfer_to[GRPQUOTA] = dqget(sb, iattr->ia_gid, GRPQUOTA); 1835 1836 ret = __dquot_transfer(inode, transfer_to); 1837 dqput_all(transfer_to); 1838 return ret; 1839} 1840EXPORT_SYMBOL(dquot_transfer); 1841 1842/* 1843 * Write info of quota file to disk 1844 */ 1845int dquot_commit_info(struct super_block *sb, int type) 1846{ 1847 int ret; 1848 struct quota_info *dqopt = sb_dqopt(sb); 1849 1850 mutex_lock(&dqopt->dqio_mutex); 1851 ret = dqopt->ops[type]->write_file_info(sb, type); 1852 mutex_unlock(&dqopt->dqio_mutex); 1853 return ret; 1854} 1855EXPORT_SYMBOL(dquot_commit_info); 1856 1857/* 1858 * Definitions of diskquota operations. 1859 */ 1860const struct dquot_operations dquot_operations = { 1861 .write_dquot = dquot_commit, 1862 .acquire_dquot = dquot_acquire, 1863 .release_dquot = dquot_release, 1864 .mark_dirty = dquot_mark_dquot_dirty, 1865 .write_info = dquot_commit_info, 1866 .alloc_dquot = dquot_alloc, 1867 .destroy_dquot = dquot_destroy, 1868}; 1869EXPORT_SYMBOL(dquot_operations); 1870 1871/* 1872 * Generic helper for ->open on filesystems supporting disk quotas. 1873 */ 1874int dquot_file_open(struct inode *inode, struct file *file) 1875{ 1876 int error; 1877 1878 error = generic_file_open(inode, file); 1879 if (!error && (file->f_mode & FMODE_WRITE)) 1880 dquot_initialize(inode); 1881 return error; 1882} 1883EXPORT_SYMBOL(dquot_file_open); 1884 1885/* 1886 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) 1887 */ 1888int dquot_disable(struct super_block *sb, int type, unsigned int flags) 1889{ 1890 int cnt, ret = 0; 1891 struct quota_info *dqopt = sb_dqopt(sb); 1892 struct inode *toputinode[MAXQUOTAS]; 1893 1894 /* Cannot turn off usage accounting without turning off limits, or 1895 * suspend quotas and simultaneously turn quotas off. */ 1896 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) 1897 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | 1898 DQUOT_USAGE_ENABLED))) 1899 return -EINVAL; 1900 1901 /* We need to serialize quota_off() for device */ 1902 mutex_lock(&dqopt->dqonoff_mutex); 1903 1904 /* 1905 * Skip everything if there's nothing to do. We have to do this because 1906 * sometimes we are called when fill_super() failed and calling 1907 * sync_fs() in such cases does no good. 1908 */ 1909 if (!sb_any_quota_loaded(sb)) { 1910 mutex_unlock(&dqopt->dqonoff_mutex); 1911 return 0; 1912 } 1913 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 1914 toputinode[cnt] = NULL; 1915 if (type != -1 && cnt != type) 1916 continue; 1917 if (!sb_has_quota_loaded(sb, cnt)) 1918 continue; 1919 1920 if (flags & DQUOT_SUSPENDED) { 1921 spin_lock(&dq_state_lock); 1922 dqopt->flags |= 1923 dquot_state_flag(DQUOT_SUSPENDED, cnt); 1924 spin_unlock(&dq_state_lock); 1925 } else { 1926 spin_lock(&dq_state_lock); 1927 dqopt->flags &= ~dquot_state_flag(flags, cnt); 1928 /* Turning off suspended quotas? */ 1929 if (!sb_has_quota_loaded(sb, cnt) && 1930 sb_has_quota_suspended(sb, cnt)) { 1931 dqopt->flags &= ~dquot_state_flag( 1932 DQUOT_SUSPENDED, cnt); 1933 spin_unlock(&dq_state_lock); 1934 iput(dqopt->files[cnt]); 1935 dqopt->files[cnt] = NULL; 1936 continue; 1937 } 1938 spin_unlock(&dq_state_lock); 1939 } 1940 1941 /* We still have to keep quota loaded? */ 1942 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) 1943 continue; 1944 1945 /* Note: these are blocking operations */ 1946 drop_dquot_ref(sb, cnt); 1947 invalidate_dquots(sb, cnt); 1948 /* 1949 * Now all dquots should be invalidated, all writes done so we 1950 * should be only users of the info. No locks needed. 1951 */ 1952 if (info_dirty(&dqopt->info[cnt])) 1953 sb->dq_op->write_info(sb, cnt); 1954 if (dqopt->ops[cnt]->free_file_info) 1955 dqopt->ops[cnt]->free_file_info(sb, cnt); 1956 put_quota_format(dqopt->info[cnt].dqi_format); 1957 1958 toputinode[cnt] = dqopt->files[cnt]; 1959 if (!sb_has_quota_loaded(sb, cnt)) 1960 dqopt->files[cnt] = NULL; 1961 dqopt->info[cnt].dqi_flags = 0; 1962 dqopt->info[cnt].dqi_igrace = 0; 1963 dqopt->info[cnt].dqi_bgrace = 0; 1964 dqopt->ops[cnt] = NULL; 1965 } 1966 mutex_unlock(&dqopt->dqonoff_mutex); 1967 1968 /* Skip syncing and setting flags if quota files are hidden */ 1969 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) 1970 goto put_inodes; 1971 1972 /* Sync the superblock so that buffers with quota data are written to 1973 * disk (and so userspace sees correct data afterwards). */ 1974 if (sb->s_op->sync_fs) 1975 sb->s_op->sync_fs(sb, 1); 1976 sync_blockdev(sb->s_bdev); 1977 /* Now the quota files are just ordinary files and we can set the 1978 * inode flags back. Moreover we discard the pagecache so that 1979 * userspace sees the writes we did bypassing the pagecache. We 1980 * must also discard the blockdev buffers so that we see the 1981 * changes done by userspace on the next quotaon() */ 1982 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 1983 if (toputinode[cnt]) { 1984 mutex_lock(&dqopt->dqonoff_mutex); 1985 /* If quota was reenabled in the meantime, we have 1986 * nothing to do */ 1987 if (!sb_has_quota_loaded(sb, cnt)) { 1988 mutex_lock_nested(&toputinode[cnt]->i_mutex, 1989 I_MUTEX_QUOTA); 1990 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | 1991 S_NOATIME | S_NOQUOTA); 1992 truncate_inode_pages(&toputinode[cnt]->i_data, 1993 0); 1994 mutex_unlock(&toputinode[cnt]->i_mutex); 1995 mark_inode_dirty_sync(toputinode[cnt]); 1996 } 1997 mutex_unlock(&dqopt->dqonoff_mutex); 1998 } 1999 if (sb->s_bdev) 2000 invalidate_bdev(sb->s_bdev); 2001put_inodes: 2002 for (cnt = 0; cnt < MAXQUOTAS; cnt++) 2003 if (toputinode[cnt]) { 2004 /* On remount RO, we keep the inode pointer so that we 2005 * can reenable quota on the subsequent remount RW. We 2006 * have to check 'flags' variable and not use sb_has_ 2007 * function because another quotaon / quotaoff could 2008 * change global state before we got here. We refuse 2009 * to suspend quotas when there is pending delete on 2010 * the quota file... */ 2011 if (!(flags & DQUOT_SUSPENDED)) 2012 iput(toputinode[cnt]); 2013 else if (!toputinode[cnt]->i_nlink) 2014 ret = -EBUSY; 2015 } 2016 return ret; 2017} 2018EXPORT_SYMBOL(dquot_disable); 2019 2020int dquot_quota_off(struct super_block *sb, int type) 2021{ 2022 return dquot_disable(sb, type, 2023 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2024} 2025EXPORT_SYMBOL(dquot_quota_off); 2026 2027/* 2028 * Turn quotas on on a device 2029 */ 2030 2031/* 2032 * Helper function to turn quotas on when we already have the inode of 2033 * quota file and no quota information is loaded. 2034 */ 2035static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, 2036 unsigned int flags) 2037{ 2038 struct quota_format_type *fmt = find_quota_format(format_id); 2039 struct super_block *sb = inode->i_sb; 2040 struct quota_info *dqopt = sb_dqopt(sb); 2041 int error; 2042 int oldflags = -1; 2043 2044 if (!fmt) 2045 return -ESRCH; 2046 if (!S_ISREG(inode->i_mode)) { 2047 error = -EACCES; 2048 goto out_fmt; 2049 } 2050 if (IS_RDONLY(inode)) { 2051 error = -EROFS; 2052 goto out_fmt; 2053 } 2054 if (!sb->s_op->quota_write || !sb->s_op->quota_read) { 2055 error = -EINVAL; 2056 goto out_fmt; 2057 } 2058 /* Usage always has to be set... */ 2059 if (!(flags & DQUOT_USAGE_ENABLED)) { 2060 error = -EINVAL; 2061 goto out_fmt; 2062 } 2063 2064 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2065 /* As we bypass the pagecache we must now flush all the 2066 * dirty data and invalidate caches so that kernel sees 2067 * changes from userspace. It is not enough to just flush 2068 * the quota file since if blocksize < pagesize, invalidation 2069 * of the cache could fail because of other unrelated dirty 2070 * data */ 2071 sync_filesystem(sb); 2072 invalidate_bdev(sb->s_bdev); 2073 } 2074 mutex_lock(&dqopt->dqonoff_mutex); 2075 if (sb_has_quota_loaded(sb, type)) { 2076 error = -EBUSY; 2077 goto out_lock; 2078 } 2079 2080 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { 2081 /* We don't want quota and atime on quota files (deadlocks 2082 * possible) Also nobody should write to the file - we use 2083 * special IO operations which ignore the immutable bit. */ 2084 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2085 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | 2086 S_NOQUOTA); 2087 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; 2088 mutex_unlock(&inode->i_mutex); 2089 /* 2090 * When S_NOQUOTA is set, remove dquot references as no more 2091 * references can be added 2092 */ 2093 __dquot_drop(inode); 2094 } 2095 2096 error = -EIO; 2097 dqopt->files[type] = igrab(inode); 2098 if (!dqopt->files[type]) 2099 goto out_lock; 2100 error = -EINVAL; 2101 if (!fmt->qf_ops->check_quota_file(sb, type)) 2102 goto out_file_init; 2103 2104 dqopt->ops[type] = fmt->qf_ops; 2105 dqopt->info[type].dqi_format = fmt; 2106 dqopt->info[type].dqi_fmt_id = format_id; 2107 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list); 2108 mutex_lock(&dqopt->dqio_mutex); 2109 error = dqopt->ops[type]->read_file_info(sb, type); 2110 if (error < 0) { 2111 mutex_unlock(&dqopt->dqio_mutex); 2112 goto out_file_init; 2113 } 2114 mutex_unlock(&dqopt->dqio_mutex); 2115 spin_lock(&dq_state_lock); 2116 dqopt->flags |= dquot_state_flag(flags, type); 2117 spin_unlock(&dq_state_lock); 2118 2119 add_dquot_ref(sb, type); 2120 mutex_unlock(&dqopt->dqonoff_mutex); 2121 2122 return 0; 2123 2124out_file_init: 2125 dqopt->files[type] = NULL; 2126 iput(inode); 2127out_lock: 2128 if (oldflags != -1) { 2129 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 2130 /* Set the flags back (in the case of accidental quotaon() 2131 * on a wrong file we don't want to mess up the flags) */ 2132 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE); 2133 inode->i_flags |= oldflags; 2134 mutex_unlock(&inode->i_mutex); 2135 } 2136 mutex_unlock(&dqopt->dqonoff_mutex); 2137out_fmt: 2138 put_quota_format(fmt); 2139 2140 return error; 2141} 2142 2143/* Reenable quotas on remount RW */ 2144int dquot_resume(struct super_block *sb, int type) 2145{ 2146 struct quota_info *dqopt = sb_dqopt(sb); 2147 struct inode *inode; 2148 int ret = 0, cnt; 2149 unsigned int flags; 2150 2151 for (cnt = 0; cnt < MAXQUOTAS; cnt++) { 2152 if (type != -1 && cnt != type) 2153 continue; 2154 2155 mutex_lock(&dqopt->dqonoff_mutex); 2156 if (!sb_has_quota_suspended(sb, cnt)) { 2157 mutex_unlock(&dqopt->dqonoff_mutex); 2158 continue; 2159 } 2160 inode = dqopt->files[cnt]; 2161 dqopt->files[cnt] = NULL; 2162 spin_lock(&dq_state_lock); 2163 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | 2164 DQUOT_LIMITS_ENABLED, 2165 cnt); 2166 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt); 2167 spin_unlock(&dq_state_lock); 2168 mutex_unlock(&dqopt->dqonoff_mutex); 2169 2170 flags = dquot_generic_flag(flags, cnt); 2171 ret = vfs_load_quota_inode(inode, cnt, 2172 dqopt->info[cnt].dqi_fmt_id, flags); 2173 iput(inode); 2174 } 2175 2176 return ret; 2177} 2178EXPORT_SYMBOL(dquot_resume); 2179 2180int dquot_quota_on_path(struct super_block *sb, int type, int format_id, 2181 struct path *path) 2182{ 2183 int error = security_quota_on(path->dentry); 2184 if (error) 2185 return error; 2186 /* Quota file not on the same filesystem? */ 2187 if (path->mnt->mnt_sb != sb) 2188 error = -EXDEV; 2189 else 2190 error = vfs_load_quota_inode(path->dentry->d_inode, type, 2191 format_id, DQUOT_USAGE_ENABLED | 2192 DQUOT_LIMITS_ENABLED); 2193 return error; 2194} 2195EXPORT_SYMBOL(dquot_quota_on_path); 2196 2197int dquot_quota_on(struct super_block *sb, int type, int format_id, char *name) 2198{ 2199 struct path path; 2200 int error; 2201 2202 error = kern_path(name, LOOKUP_FOLLOW, &path); 2203 if (!error) { 2204 error = dquot_quota_on_path(sb, type, format_id, &path); 2205 path_put(&path); 2206 } 2207 return error; 2208} 2209EXPORT_SYMBOL(dquot_quota_on); 2210 2211/* 2212 * More powerful function for turning on quotas allowing setting 2213 * of individual quota flags 2214 */ 2215int dquot_enable(struct inode *inode, int type, int format_id, 2216 unsigned int flags) 2217{ 2218 int ret = 0; 2219 struct super_block *sb = inode->i_sb; 2220 struct quota_info *dqopt = sb_dqopt(sb); 2221 2222 /* Just unsuspend quotas? */ 2223 BUG_ON(flags & DQUOT_SUSPENDED); 2224 2225 if (!flags) 2226 return 0; 2227 /* Just updating flags needed? */ 2228 if (sb_has_quota_loaded(sb, type)) { 2229 mutex_lock(&dqopt->dqonoff_mutex); 2230 /* Now do a reliable test... */ 2231 if (!sb_has_quota_loaded(sb, type)) { 2232 mutex_unlock(&dqopt->dqonoff_mutex); 2233 goto load_quota; 2234 } 2235 if (flags & DQUOT_USAGE_ENABLED && 2236 sb_has_quota_usage_enabled(sb, type)) { 2237 ret = -EBUSY; 2238 goto out_lock; 2239 } 2240 if (flags & DQUOT_LIMITS_ENABLED && 2241 sb_has_quota_limits_enabled(sb, type)) { 2242 ret = -EBUSY; 2243 goto out_lock; 2244 } 2245 spin_lock(&dq_state_lock); 2246 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); 2247 spin_unlock(&dq_state_lock); 2248out_lock: 2249 mutex_unlock(&dqopt->dqonoff_mutex); 2250 return ret; 2251 } 2252 2253load_quota: 2254 return vfs_load_quota_inode(inode, type, format_id, flags); 2255} 2256EXPORT_SYMBOL(dquot_enable); 2257 2258/* 2259 * This function is used when filesystem needs to initialize quotas 2260 * during mount time. 2261 */ 2262int dquot_quota_on_mount(struct super_block *sb, char *qf_name, 2263 int format_id, int type) 2264{ 2265 struct dentry *dentry; 2266 int error; 2267 2268 mutex_lock(&sb->s_root->d_inode->i_mutex); 2269 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name)); 2270 mutex_unlock(&sb->s_root->d_inode->i_mutex); 2271 if (IS_ERR(dentry)) 2272 return PTR_ERR(dentry); 2273 2274 if (!dentry->d_inode) { 2275 error = -ENOENT; 2276 goto out; 2277 } 2278 2279 error = security_quota_on(dentry); 2280 if (!error) 2281 error = vfs_load_quota_inode(dentry->d_inode, type, format_id, 2282 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 2283 2284out: 2285 dput(dentry); 2286 return error; 2287} 2288EXPORT_SYMBOL(dquot_quota_on_mount); 2289 2290static inline qsize_t qbtos(qsize_t blocks) 2291{ 2292 return blocks << QIF_DQBLKSIZE_BITS; 2293} 2294 2295static inline qsize_t stoqb(qsize_t space) 2296{ 2297 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; 2298} 2299 2300/* Generic routine for getting common part of quota structure */ 2301static void do_get_dqblk(struct dquot *dquot, struct fs_disk_quota *di) 2302{ 2303 struct mem_dqblk *dm = &dquot->dq_dqb; 2304 2305 memset(di, 0, sizeof(*di)); 2306 di->d_version = FS_DQUOT_VERSION; 2307 di->d_flags = dquot->dq_type == USRQUOTA ? 2308 FS_USER_QUOTA : FS_GROUP_QUOTA; 2309 di->d_id = dquot->dq_id; 2310 2311 spin_lock(&dq_data_lock); 2312 di->d_blk_hardlimit = stoqb(dm->dqb_bhardlimit); 2313 di->d_blk_softlimit = stoqb(dm->dqb_bsoftlimit); 2314 di->d_ino_hardlimit = dm->dqb_ihardlimit; 2315 di->d_ino_softlimit = dm->dqb_isoftlimit; 2316 di->d_bcount = dm->dqb_curspace + dm->dqb_rsvspace; 2317 di->d_icount = dm->dqb_curinodes; 2318 di->d_btimer = dm->dqb_btime; 2319 di->d_itimer = dm->dqb_itime; 2320 spin_unlock(&dq_data_lock); 2321} 2322 2323int dquot_get_dqblk(struct super_block *sb, int type, qid_t id, 2324 struct fs_disk_quota *di) 2325{ 2326 struct dquot *dquot; 2327 2328 dquot = dqget(sb, id, type); 2329 if (!dquot) 2330 return -ESRCH; 2331 do_get_dqblk(dquot, di); 2332 dqput(dquot); 2333 2334 return 0; 2335} 2336EXPORT_SYMBOL(dquot_get_dqblk); 2337 2338#define VFS_FS_DQ_MASK \ 2339 (FS_DQ_BCOUNT | FS_DQ_BSOFT | FS_DQ_BHARD | \ 2340 FS_DQ_ICOUNT | FS_DQ_ISOFT | FS_DQ_IHARD | \ 2341 FS_DQ_BTIMER | FS_DQ_ITIMER) 2342 2343/* Generic routine for setting common part of quota structure */ 2344static int do_set_dqblk(struct dquot *dquot, struct fs_disk_quota *di) 2345{ 2346 struct mem_dqblk *dm = &dquot->dq_dqb; 2347 int check_blim = 0, check_ilim = 0; 2348 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type]; 2349 2350 if (di->d_fieldmask & ~VFS_FS_DQ_MASK) 2351 return -EINVAL; 2352 2353 if (((di->d_fieldmask & FS_DQ_BSOFT) && 2354 (di->d_blk_softlimit > dqi->dqi_maxblimit)) || 2355 ((di->d_fieldmask & FS_DQ_BHARD) && 2356 (di->d_blk_hardlimit > dqi->dqi_maxblimit)) || 2357 ((di->d_fieldmask & FS_DQ_ISOFT) && 2358 (di->d_ino_softlimit > dqi->dqi_maxilimit)) || 2359 ((di->d_fieldmask & FS_DQ_IHARD) && 2360 (di->d_ino_hardlimit > dqi->dqi_maxilimit))) 2361 return -ERANGE; 2362 2363 spin_lock(&dq_data_lock); 2364 if (di->d_fieldmask & FS_DQ_BCOUNT) { 2365 dm->dqb_curspace = di->d_bcount - dm->dqb_rsvspace; 2366 check_blim = 1; 2367 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); 2368 } 2369 2370 if (di->d_fieldmask & FS_DQ_BSOFT) 2371 dm->dqb_bsoftlimit = qbtos(di->d_blk_softlimit); 2372 if (di->d_fieldmask & FS_DQ_BHARD) 2373 dm->dqb_bhardlimit = qbtos(di->d_blk_hardlimit); 2374 if (di->d_fieldmask & (FS_DQ_BSOFT | FS_DQ_BHARD)) { 2375 check_blim = 1; 2376 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); 2377 } 2378 2379 if (di->d_fieldmask & FS_DQ_ICOUNT) { 2380 dm->dqb_curinodes = di->d_icount; 2381 check_ilim = 1; 2382 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); 2383 } 2384 2385 if (di->d_fieldmask & FS_DQ_ISOFT) 2386 dm->dqb_isoftlimit = di->d_ino_softlimit; 2387 if (di->d_fieldmask & FS_DQ_IHARD) 2388 dm->dqb_ihardlimit = di->d_ino_hardlimit; 2389 if (di->d_fieldmask & (FS_DQ_ISOFT | FS_DQ_IHARD)) { 2390 check_ilim = 1; 2391 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); 2392 } 2393 2394 if (di->d_fieldmask & FS_DQ_BTIMER) { 2395 dm->dqb_btime = di->d_btimer; 2396 check_blim = 1; 2397 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); 2398 } 2399 2400 if (di->d_fieldmask & FS_DQ_ITIMER) { 2401 dm->dqb_itime = di->d_itimer; 2402 check_ilim = 1; 2403 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); 2404 } 2405 2406 if (check_blim) { 2407 if (!dm->dqb_bsoftlimit || 2408 dm->dqb_curspace < dm->dqb_bsoftlimit) { 2409 dm->dqb_btime = 0; 2410 clear_bit(DQ_BLKS_B, &dquot->dq_flags); 2411 } else if (!(di->d_fieldmask & FS_DQ_BTIMER)) 2412 /* Set grace only if user hasn't provided his own... */ 2413 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace; 2414 } 2415 if (check_ilim) { 2416 if (!dm->dqb_isoftlimit || 2417 dm->dqb_curinodes < dm->dqb_isoftlimit) { 2418 dm->dqb_itime = 0; 2419 clear_bit(DQ_INODES_B, &dquot->dq_flags); 2420 } else if (!(di->d_fieldmask & FS_DQ_ITIMER)) 2421 /* Set grace only if user hasn't provided his own... */ 2422 dm->dqb_itime = get_seconds() + dqi->dqi_igrace; 2423 } 2424 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || 2425 dm->dqb_isoftlimit) 2426 clear_bit(DQ_FAKE_B, &dquot->dq_flags); 2427 else 2428 set_bit(DQ_FAKE_B, &dquot->dq_flags); 2429 spin_unlock(&dq_data_lock); 2430 mark_dquot_dirty(dquot); 2431 2432 return 0; 2433} 2434 2435int dquot_set_dqblk(struct super_block *sb, int type, qid_t id, 2436 struct fs_disk_quota *di) 2437{ 2438 struct dquot *dquot; 2439 int rc; 2440 2441 dquot = dqget(sb, id, type); 2442 if (!dquot) { 2443 rc = -ESRCH; 2444 goto out; 2445 } 2446 rc = do_set_dqblk(dquot, di); 2447 dqput(dquot); 2448out: 2449 return rc; 2450} 2451EXPORT_SYMBOL(dquot_set_dqblk); 2452 2453/* Generic routine for getting common part of quota file information */ 2454int dquot_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2455{ 2456 struct mem_dqinfo *mi; 2457 2458 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2459 if (!sb_has_quota_active(sb, type)) { 2460 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2461 return -ESRCH; 2462 } 2463 mi = sb_dqopt(sb)->info + type; 2464 spin_lock(&dq_data_lock); 2465 ii->dqi_bgrace = mi->dqi_bgrace; 2466 ii->dqi_igrace = mi->dqi_igrace; 2467 ii->dqi_flags = mi->dqi_flags & DQF_MASK; 2468 ii->dqi_valid = IIF_ALL; 2469 spin_unlock(&dq_data_lock); 2470 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2471 return 0; 2472} 2473EXPORT_SYMBOL(dquot_get_dqinfo); 2474 2475/* Generic routine for setting common part of quota file information */ 2476int dquot_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) 2477{ 2478 struct mem_dqinfo *mi; 2479 int err = 0; 2480 2481 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); 2482 if (!sb_has_quota_active(sb, type)) { 2483 err = -ESRCH; 2484 goto out; 2485 } 2486 mi = sb_dqopt(sb)->info + type; 2487 spin_lock(&dq_data_lock); 2488 if (ii->dqi_valid & IIF_BGRACE) 2489 mi->dqi_bgrace = ii->dqi_bgrace; 2490 if (ii->dqi_valid & IIF_IGRACE) 2491 mi->dqi_igrace = ii->dqi_igrace; 2492 if (ii->dqi_valid & IIF_FLAGS) 2493 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | 2494 (ii->dqi_flags & DQF_MASK); 2495 spin_unlock(&dq_data_lock); 2496 mark_info_dirty(sb, type); 2497 /* Force write to disk */ 2498 sb->dq_op->write_info(sb, type); 2499out: 2500 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); 2501 return err; 2502} 2503EXPORT_SYMBOL(dquot_set_dqinfo); 2504 2505const struct quotactl_ops dquot_quotactl_ops = { 2506 .quota_on = dquot_quota_on, 2507 .quota_off = dquot_quota_off, 2508 .quota_sync = dquot_quota_sync, 2509 .get_info = dquot_get_dqinfo, 2510 .set_info = dquot_set_dqinfo, 2511 .get_dqblk = dquot_get_dqblk, 2512 .set_dqblk = dquot_set_dqblk 2513}; 2514EXPORT_SYMBOL(dquot_quotactl_ops); 2515 2516static int do_proc_dqstats(struct ctl_table *table, int write, 2517 void __user *buffer, size_t *lenp, loff_t *ppos) 2518{ 2519 unsigned int type = (int *)table->data - dqstats.stat; 2520 2521 /* Update global table */ 2522 dqstats.stat[type] = 2523 percpu_counter_sum_positive(&dqstats.counter[type]); 2524 return proc_dointvec(table, write, buffer, lenp, ppos); 2525} 2526 2527static ctl_table fs_dqstats_table[] = { 2528 { 2529 .procname = "lookups", 2530 .data = &dqstats.stat[DQST_LOOKUPS], 2531 .maxlen = sizeof(int), 2532 .mode = 0444, 2533 .proc_handler = do_proc_dqstats, 2534 }, 2535 { 2536 .procname = "drops", 2537 .data = &dqstats.stat[DQST_DROPS], 2538 .maxlen = sizeof(int), 2539 .mode = 0444, 2540 .proc_handler = do_proc_dqstats, 2541 }, 2542 { 2543 .procname = "reads", 2544 .data = &dqstats.stat[DQST_READS], 2545 .maxlen = sizeof(int), 2546 .mode = 0444, 2547 .proc_handler = do_proc_dqstats, 2548 }, 2549 { 2550 .procname = "writes", 2551 .data = &dqstats.stat[DQST_WRITES], 2552 .maxlen = sizeof(int), 2553 .mode = 0444, 2554 .proc_handler = do_proc_dqstats, 2555 }, 2556 { 2557 .procname = "cache_hits", 2558 .data = &dqstats.stat[DQST_CACHE_HITS], 2559 .maxlen = sizeof(int), 2560 .mode = 0444, 2561 .proc_handler = do_proc_dqstats, 2562 }, 2563 { 2564 .procname = "allocated_dquots", 2565 .data = &dqstats.stat[DQST_ALLOC_DQUOTS], 2566 .maxlen = sizeof(int), 2567 .mode = 0444, 2568 .proc_handler = do_proc_dqstats, 2569 }, 2570 { 2571 .procname = "free_dquots", 2572 .data = &dqstats.stat[DQST_FREE_DQUOTS], 2573 .maxlen = sizeof(int), 2574 .mode = 0444, 2575 .proc_handler = do_proc_dqstats, 2576 }, 2577 { 2578 .procname = "syncs", 2579 .data = &dqstats.stat[DQST_SYNCS], 2580 .maxlen = sizeof(int), 2581 .mode = 0444, 2582 .proc_handler = do_proc_dqstats, 2583 }, 2584#ifdef CONFIG_PRINT_QUOTA_WARNING 2585 { 2586 .procname = "warnings", 2587 .data = &flag_print_warnings, 2588 .maxlen = sizeof(int), 2589 .mode = 0644, 2590 .proc_handler = proc_dointvec, 2591 }, 2592#endif 2593 { }, 2594}; 2595 2596static ctl_table fs_table[] = { 2597 { 2598 .procname = "quota", 2599 .mode = 0555, 2600 .child = fs_dqstats_table, 2601 }, 2602 { }, 2603}; 2604 2605static ctl_table sys_table[] = { 2606 { 2607 .procname = "fs", 2608 .mode = 0555, 2609 .child = fs_table, 2610 }, 2611 { }, 2612}; 2613 2614static int __init dquot_init(void) 2615{ 2616 int i, ret; 2617 unsigned long nr_hash, order; 2618 2619 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__); 2620 2621 register_sysctl_table(sys_table); 2622 2623 dquot_cachep = kmem_cache_create("dquot", 2624 sizeof(struct dquot), sizeof(unsigned long) * 4, 2625 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 2626 SLAB_MEM_SPREAD|SLAB_PANIC), 2627 NULL); 2628 2629 order = 0; 2630 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order); 2631 if (!dquot_hash) 2632 panic("Cannot create dquot hash table"); 2633 2634 for (i = 0; i < _DQST_DQSTAT_LAST; i++) { 2635 ret = percpu_counter_init(&dqstats.counter[i], 0); 2636 if (ret) 2637 panic("Cannot create dquot stat counters"); 2638 } 2639 2640 /* Find power-of-two hlist_heads which can fit into allocation */ 2641 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head); 2642 dq_hash_bits = 0; 2643 do { 2644 dq_hash_bits++; 2645 } while (nr_hash >> dq_hash_bits); 2646 dq_hash_bits--; 2647 2648 nr_hash = 1UL << dq_hash_bits; 2649 dq_hash_mask = nr_hash - 1; 2650 for (i = 0; i < nr_hash; i++) 2651 INIT_HLIST_HEAD(dquot_hash + i); 2652 2653 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n", 2654 nr_hash, order, (PAGE_SIZE << order)); 2655 2656 register_shrinker(&dqcache_shrinker); 2657 2658 return 0; 2659} 2660module_init(dquot_init); 2661