| 1 | /* |
| 2 | * Copyright (C) 2007 Oracle. All rights reserved. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public |
| 6 | * License v2 as published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 11 | * General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public |
| 14 | * License along with this program; if not, write to the |
| 15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 16 | * Boston, MA 021110-1307, USA. |
| 17 | */ |
| 18 | |
| 19 | #include <linux/blkdev.h> |
| 20 | #include <linux/module.h> |
| 21 | #include <linux/buffer_head.h> |
| 22 | #include <linux/fs.h> |
| 23 | #include <linux/pagemap.h> |
| 24 | #include <linux/highmem.h> |
| 25 | #include <linux/time.h> |
| 26 | #include <linux/init.h> |
| 27 | #include <linux/seq_file.h> |
| 28 | #include <linux/string.h> |
| 29 | #include <linux/backing-dev.h> |
| 30 | #include <linux/mount.h> |
| 31 | #include <linux/mpage.h> |
| 32 | #include <linux/swap.h> |
| 33 | #include <linux/writeback.h> |
| 34 | #include <linux/statfs.h> |
| 35 | #include <linux/compat.h> |
| 36 | #include <linux/parser.h> |
| 37 | #include <linux/ctype.h> |
| 38 | #include <linux/namei.h> |
| 39 | #include <linux/miscdevice.h> |
| 40 | #include <linux/magic.h> |
| 41 | #include <linux/slab.h> |
| 42 | #include <linux/cleancache.h> |
| 43 | #include <linux/ratelimit.h> |
| 44 | #include <linux/btrfs.h> |
| 45 | #include "delayed-inode.h" |
| 46 | #include "ctree.h" |
| 47 | #include "disk-io.h" |
| 48 | #include "transaction.h" |
| 49 | #include "btrfs_inode.h" |
| 50 | #include "print-tree.h" |
| 51 | #include "hash.h" |
| 52 | #include "props.h" |
| 53 | #include "xattr.h" |
| 54 | #include "volumes.h" |
| 55 | #include "export.h" |
| 56 | #include "compression.h" |
| 57 | #include "rcu-string.h" |
| 58 | #include "dev-replace.h" |
| 59 | #include "free-space-cache.h" |
| 60 | #include "backref.h" |
| 61 | #include "tests/btrfs-tests.h" |
| 62 | |
| 63 | #include "qgroup.h" |
| 64 | #include "backref.h" |
| 65 | #define CREATE_TRACE_POINTS |
| 66 | #include <trace/events/btrfs.h> |
| 67 | |
| 68 | static const struct super_operations btrfs_super_ops; |
| 69 | static struct file_system_type btrfs_fs_type; |
| 70 | |
| 71 | static int btrfs_remount(struct super_block *sb, int *flags, char *data); |
| 72 | |
| 73 | const char *btrfs_decode_error(int errno) |
| 74 | { |
| 75 | char *errstr = "unknown"; |
| 76 | |
| 77 | switch (errno) { |
| 78 | case -EIO: |
| 79 | errstr = "IO failure"; |
| 80 | break; |
| 81 | case -ENOMEM: |
| 82 | errstr = "Out of memory"; |
| 83 | break; |
| 84 | case -EROFS: |
| 85 | errstr = "Readonly filesystem"; |
| 86 | break; |
| 87 | case -EEXIST: |
| 88 | errstr = "Object already exists"; |
| 89 | break; |
| 90 | case -ENOSPC: |
| 91 | errstr = "No space left"; |
| 92 | break; |
| 93 | case -ENOENT: |
| 94 | errstr = "No such entry"; |
| 95 | break; |
| 96 | } |
| 97 | |
| 98 | return errstr; |
| 99 | } |
| 100 | |
| 101 | /* btrfs handle error by forcing the filesystem readonly */ |
| 102 | static void btrfs_handle_error(struct btrfs_fs_info *fs_info) |
| 103 | { |
| 104 | struct super_block *sb = fs_info->sb; |
| 105 | |
| 106 | if (sb_rdonly(sb)) |
| 107 | return; |
| 108 | |
| 109 | if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) { |
| 110 | sb->s_flags |= MS_RDONLY; |
| 111 | btrfs_info(fs_info, "forced readonly"); |
| 112 | /* |
| 113 | * Note that a running device replace operation is not |
| 114 | * canceled here although there is no way to update |
| 115 | * the progress. It would add the risk of a deadlock, |
| 116 | * therefore the canceling is omitted. The only penalty |
| 117 | * is that some I/O remains active until the procedure |
| 118 | * completes. The next time when the filesystem is |
| 119 | * mounted writeable again, the device replace |
| 120 | * operation continues. |
| 121 | */ |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | /* |
| 126 | * __btrfs_handle_fs_error decodes expected errors from the caller and |
| 127 | * invokes the approciate error response. |
| 128 | */ |
| 129 | __cold |
| 130 | void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function, |
| 131 | unsigned int line, int errno, const char *fmt, ...) |
| 132 | { |
| 133 | struct super_block *sb = fs_info->sb; |
| 134 | #ifdef CONFIG_PRINTK |
| 135 | const char *errstr; |
| 136 | #endif |
| 137 | |
| 138 | /* |
| 139 | * Special case: if the error is EROFS, and we're already |
| 140 | * under MS_RDONLY, then it is safe here. |
| 141 | */ |
| 142 | if (errno == -EROFS && sb_rdonly(sb)) |
| 143 | return; |
| 144 | |
| 145 | #ifdef CONFIG_PRINTK |
| 146 | errstr = btrfs_decode_error(errno); |
| 147 | if (fmt) { |
| 148 | struct va_format vaf; |
| 149 | va_list args; |
| 150 | |
| 151 | va_start(args, fmt); |
| 152 | vaf.fmt = fmt; |
| 153 | vaf.va = &args; |
| 154 | |
| 155 | pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s (%pV)\n", |
| 156 | sb->s_id, function, line, errno, errstr, &vaf); |
| 157 | va_end(args); |
| 158 | } else { |
| 159 | pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s\n", |
| 160 | sb->s_id, function, line, errno, errstr); |
| 161 | } |
| 162 | #endif |
| 163 | |
| 164 | /* |
| 165 | * Today we only save the error info to memory. Long term we'll |
| 166 | * also send it down to the disk |
| 167 | */ |
| 168 | set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state); |
| 169 | |
| 170 | /* Don't go through full error handling during mount */ |
| 171 | if (sb->s_flags & MS_BORN) |
| 172 | btrfs_handle_error(fs_info); |
| 173 | } |
| 174 | |
| 175 | #ifdef CONFIG_PRINTK |
| 176 | static const char * const logtypes[] = { |
| 177 | "emergency", |
| 178 | "alert", |
| 179 | "critical", |
| 180 | "error", |
| 181 | "warning", |
| 182 | "notice", |
| 183 | "info", |
| 184 | "debug", |
| 185 | }; |
| 186 | |
| 187 | |
| 188 | /* |
| 189 | * Use one ratelimit state per log level so that a flood of less important |
| 190 | * messages doesn't cause more important ones to be dropped. |
| 191 | */ |
| 192 | static struct ratelimit_state printk_limits[] = { |
| 193 | RATELIMIT_STATE_INIT(printk_limits[0], DEFAULT_RATELIMIT_INTERVAL, 100), |
| 194 | RATELIMIT_STATE_INIT(printk_limits[1], DEFAULT_RATELIMIT_INTERVAL, 100), |
| 195 | RATELIMIT_STATE_INIT(printk_limits[2], DEFAULT_RATELIMIT_INTERVAL, 100), |
| 196 | RATELIMIT_STATE_INIT(printk_limits[3], DEFAULT_RATELIMIT_INTERVAL, 100), |
| 197 | RATELIMIT_STATE_INIT(printk_limits[4], DEFAULT_RATELIMIT_INTERVAL, 100), |
| 198 | RATELIMIT_STATE_INIT(printk_limits[5], DEFAULT_RATELIMIT_INTERVAL, 100), |
| 199 | RATELIMIT_STATE_INIT(printk_limits[6], DEFAULT_RATELIMIT_INTERVAL, 100), |
| 200 | RATELIMIT_STATE_INIT(printk_limits[7], DEFAULT_RATELIMIT_INTERVAL, 100), |
| 201 | }; |
| 202 | |
| 203 | void btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...) |
| 204 | { |
| 205 | struct super_block *sb = fs_info->sb; |
| 206 | char lvl[PRINTK_MAX_SINGLE_HEADER_LEN + 1] = "\0"; |
| 207 | struct va_format vaf; |
| 208 | va_list args; |
| 209 | int kern_level; |
| 210 | const char *type = logtypes[4]; |
| 211 | struct ratelimit_state *ratelimit = &printk_limits[4]; |
| 212 | |
| 213 | va_start(args, fmt); |
| 214 | |
| 215 | while ((kern_level = printk_get_level(fmt)) != 0) { |
| 216 | size_t size = printk_skip_level(fmt) - fmt; |
| 217 | |
| 218 | if (kern_level >= '0' && kern_level <= '7') { |
| 219 | memcpy(lvl, fmt, size); |
| 220 | lvl[size] = '\0'; |
| 221 | type = logtypes[kern_level - '0']; |
| 222 | ratelimit = &printk_limits[kern_level - '0']; |
| 223 | } |
| 224 | fmt += size; |
| 225 | } |
| 226 | |
| 227 | vaf.fmt = fmt; |
| 228 | vaf.va = &args; |
| 229 | |
| 230 | if (__ratelimit(ratelimit)) |
| 231 | printk("%sBTRFS %s (device %s): %pV\n", lvl, type, sb->s_id, &vaf); |
| 232 | |
| 233 | va_end(args); |
| 234 | } |
| 235 | #endif |
| 236 | |
| 237 | /* |
| 238 | * We only mark the transaction aborted and then set the file system read-only. |
| 239 | * This will prevent new transactions from starting or trying to join this |
| 240 | * one. |
| 241 | * |
| 242 | * This means that error recovery at the call site is limited to freeing |
| 243 | * any local memory allocations and passing the error code up without |
| 244 | * further cleanup. The transaction should complete as it normally would |
| 245 | * in the call path but will return -EIO. |
| 246 | * |
| 247 | * We'll complete the cleanup in btrfs_end_transaction and |
| 248 | * btrfs_commit_transaction. |
| 249 | */ |
| 250 | __cold |
| 251 | void __btrfs_abort_transaction(struct btrfs_trans_handle *trans, |
| 252 | const char *function, |
| 253 | unsigned int line, int errno) |
| 254 | { |
| 255 | struct btrfs_fs_info *fs_info = trans->fs_info; |
| 256 | |
| 257 | trans->aborted = errno; |
| 258 | /* Nothing used. The other threads that have joined this |
| 259 | * transaction may be able to continue. */ |
| 260 | if (!trans->dirty && list_empty(&trans->new_bgs)) { |
| 261 | const char *errstr; |
| 262 | |
| 263 | errstr = btrfs_decode_error(errno); |
| 264 | btrfs_warn(fs_info, |
| 265 | "%s:%d: Aborting unused transaction(%s).", |
| 266 | function, line, errstr); |
| 267 | return; |
| 268 | } |
| 269 | WRITE_ONCE(trans->transaction->aborted, errno); |
| 270 | /* Wake up anybody who may be waiting on this transaction */ |
| 271 | wake_up(&fs_info->transaction_wait); |
| 272 | wake_up(&fs_info->transaction_blocked_wait); |
| 273 | __btrfs_handle_fs_error(fs_info, function, line, errno, NULL); |
| 274 | } |
| 275 | /* |
| 276 | * __btrfs_panic decodes unexpected, fatal errors from the caller, |
| 277 | * issues an alert, and either panics or BUGs, depending on mount options. |
| 278 | */ |
| 279 | __cold |
| 280 | void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function, |
| 281 | unsigned int line, int errno, const char *fmt, ...) |
| 282 | { |
| 283 | char *s_id = "<unknown>"; |
| 284 | const char *errstr; |
| 285 | struct va_format vaf = { .fmt = fmt }; |
| 286 | va_list args; |
| 287 | |
| 288 | if (fs_info) |
| 289 | s_id = fs_info->sb->s_id; |
| 290 | |
| 291 | va_start(args, fmt); |
| 292 | vaf.va = &args; |
| 293 | |
| 294 | errstr = btrfs_decode_error(errno); |
| 295 | if (fs_info && (fs_info->mount_opt & BTRFS_MOUNT_PANIC_ON_FATAL_ERROR)) |
| 296 | panic(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (errno=%d %s)\n", |
| 297 | s_id, function, line, &vaf, errno, errstr); |
| 298 | |
| 299 | btrfs_crit(fs_info, "panic in %s:%d: %pV (errno=%d %s)", |
| 300 | function, line, &vaf, errno, errstr); |
| 301 | va_end(args); |
| 302 | /* Caller calls BUG() */ |
| 303 | } |
| 304 | |
| 305 | static void btrfs_put_super(struct super_block *sb) |
| 306 | { |
| 307 | close_ctree(btrfs_sb(sb)); |
| 308 | } |
| 309 | |
| 310 | enum { |
| 311 | Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum, |
| 312 | Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, |
| 313 | Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, |
| 314 | Opt_compress_type, Opt_compress_force, Opt_compress_force_type, |
| 315 | Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard, |
| 316 | Opt_space_cache, Opt_space_cache_version, Opt_clear_cache, |
| 317 | Opt_user_subvol_rm_allowed, Opt_enospc_debug, Opt_subvolrootid, |
| 318 | Opt_defrag, Opt_inode_cache, Opt_no_space_cache, Opt_recovery, |
| 319 | Opt_skip_balance, Opt_check_integrity, |
| 320 | Opt_check_integrity_including_extent_data, |
| 321 | Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree, |
| 322 | Opt_commit_interval, Opt_barrier, Opt_nodefrag, Opt_nodiscard, |
| 323 | Opt_noenospc_debug, Opt_noflushoncommit, Opt_acl, Opt_datacow, |
| 324 | Opt_datasum, Opt_treelog, Opt_noinode_cache, Opt_usebackuproot, |
| 325 | Opt_nologreplay, Opt_norecovery, |
| 326 | #ifdef CONFIG_BTRFS_DEBUG |
| 327 | Opt_fragment_data, Opt_fragment_metadata, Opt_fragment_all, |
| 328 | #endif |
| 329 | Opt_err, |
| 330 | }; |
| 331 | |
| 332 | static const match_table_t tokens = { |
| 333 | {Opt_degraded, "degraded"}, |
| 334 | {Opt_subvol, "subvol=%s"}, |
| 335 | {Opt_subvolid, "subvolid=%s"}, |
| 336 | {Opt_device, "device=%s"}, |
| 337 | {Opt_nodatasum, "nodatasum"}, |
| 338 | {Opt_datasum, "datasum"}, |
| 339 | {Opt_nodatacow, "nodatacow"}, |
| 340 | {Opt_datacow, "datacow"}, |
| 341 | {Opt_nobarrier, "nobarrier"}, |
| 342 | {Opt_barrier, "barrier"}, |
| 343 | {Opt_max_inline, "max_inline=%s"}, |
| 344 | {Opt_alloc_start, "alloc_start=%s"}, |
| 345 | {Opt_thread_pool, "thread_pool=%d"}, |
| 346 | {Opt_compress, "compress"}, |
| 347 | {Opt_compress_type, "compress=%s"}, |
| 348 | {Opt_compress_force, "compress-force"}, |
| 349 | {Opt_compress_force_type, "compress-force=%s"}, |
| 350 | {Opt_ssd, "ssd"}, |
| 351 | {Opt_ssd_spread, "ssd_spread"}, |
| 352 | {Opt_nossd, "nossd"}, |
| 353 | {Opt_acl, "acl"}, |
| 354 | {Opt_noacl, "noacl"}, |
| 355 | {Opt_notreelog, "notreelog"}, |
| 356 | {Opt_treelog, "treelog"}, |
| 357 | {Opt_nologreplay, "nologreplay"}, |
| 358 | {Opt_norecovery, "norecovery"}, |
| 359 | {Opt_flushoncommit, "flushoncommit"}, |
| 360 | {Opt_noflushoncommit, "noflushoncommit"}, |
| 361 | {Opt_ratio, "metadata_ratio=%d"}, |
| 362 | {Opt_discard, "discard"}, |
| 363 | {Opt_nodiscard, "nodiscard"}, |
| 364 | {Opt_space_cache, "space_cache"}, |
| 365 | {Opt_space_cache_version, "space_cache=%s"}, |
| 366 | {Opt_clear_cache, "clear_cache"}, |
| 367 | {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, |
| 368 | {Opt_enospc_debug, "enospc_debug"}, |
| 369 | {Opt_noenospc_debug, "noenospc_debug"}, |
| 370 | {Opt_subvolrootid, "subvolrootid=%d"}, |
| 371 | {Opt_defrag, "autodefrag"}, |
| 372 | {Opt_nodefrag, "noautodefrag"}, |
| 373 | {Opt_inode_cache, "inode_cache"}, |
| 374 | {Opt_noinode_cache, "noinode_cache"}, |
| 375 | {Opt_no_space_cache, "nospace_cache"}, |
| 376 | {Opt_recovery, "recovery"}, /* deprecated */ |
| 377 | {Opt_usebackuproot, "usebackuproot"}, |
| 378 | {Opt_skip_balance, "skip_balance"}, |
| 379 | {Opt_check_integrity, "check_int"}, |
| 380 | {Opt_check_integrity_including_extent_data, "check_int_data"}, |
| 381 | {Opt_check_integrity_print_mask, "check_int_print_mask=%d"}, |
| 382 | {Opt_rescan_uuid_tree, "rescan_uuid_tree"}, |
| 383 | {Opt_fatal_errors, "fatal_errors=%s"}, |
| 384 | {Opt_commit_interval, "commit=%d"}, |
| 385 | #ifdef CONFIG_BTRFS_DEBUG |
| 386 | {Opt_fragment_data, "fragment=data"}, |
| 387 | {Opt_fragment_metadata, "fragment=metadata"}, |
| 388 | {Opt_fragment_all, "fragment=all"}, |
| 389 | #endif |
| 390 | {Opt_err, NULL}, |
| 391 | }; |
| 392 | |
| 393 | /* |
| 394 | * Regular mount options parser. Everything that is needed only when |
| 395 | * reading in a new superblock is parsed here. |
| 396 | * XXX JDM: This needs to be cleaned up for remount. |
| 397 | */ |
| 398 | int btrfs_parse_options(struct btrfs_fs_info *info, char *options, |
| 399 | unsigned long new_flags) |
| 400 | { |
| 401 | substring_t args[MAX_OPT_ARGS]; |
| 402 | char *p, *num, *orig = NULL; |
| 403 | u64 cache_gen; |
| 404 | int intarg; |
| 405 | int ret = 0; |
| 406 | char *compress_type; |
| 407 | bool compress_force = false; |
| 408 | enum btrfs_compression_type saved_compress_type; |
| 409 | bool saved_compress_force; |
| 410 | int no_compress = 0; |
| 411 | |
| 412 | cache_gen = btrfs_super_cache_generation(info->super_copy); |
| 413 | if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE)) |
| 414 | btrfs_set_opt(info->mount_opt, FREE_SPACE_TREE); |
| 415 | else if (cache_gen) |
| 416 | btrfs_set_opt(info->mount_opt, SPACE_CACHE); |
| 417 | |
| 418 | /* |
| 419 | * Even the options are empty, we still need to do extra check |
| 420 | * against new flags |
| 421 | */ |
| 422 | if (!options) |
| 423 | goto check; |
| 424 | |
| 425 | /* |
| 426 | * strsep changes the string, duplicate it because parse_options |
| 427 | * gets called twice |
| 428 | */ |
| 429 | options = kstrdup(options, GFP_KERNEL); |
| 430 | if (!options) |
| 431 | return -ENOMEM; |
| 432 | |
| 433 | orig = options; |
| 434 | |
| 435 | while ((p = strsep(&options, ",")) != NULL) { |
| 436 | int token; |
| 437 | if (!*p) |
| 438 | continue; |
| 439 | |
| 440 | token = match_token(p, tokens, args); |
| 441 | switch (token) { |
| 442 | case Opt_degraded: |
| 443 | btrfs_info(info, "allowing degraded mounts"); |
| 444 | btrfs_set_opt(info->mount_opt, DEGRADED); |
| 445 | break; |
| 446 | case Opt_subvol: |
| 447 | case Opt_subvolid: |
| 448 | case Opt_subvolrootid: |
| 449 | case Opt_device: |
| 450 | /* |
| 451 | * These are parsed by btrfs_parse_early_options |
| 452 | * and can be happily ignored here. |
| 453 | */ |
| 454 | break; |
| 455 | case Opt_nodatasum: |
| 456 | btrfs_set_and_info(info, NODATASUM, |
| 457 | "setting nodatasum"); |
| 458 | break; |
| 459 | case Opt_datasum: |
| 460 | if (btrfs_test_opt(info, NODATASUM)) { |
| 461 | if (btrfs_test_opt(info, NODATACOW)) |
| 462 | btrfs_info(info, |
| 463 | "setting datasum, datacow enabled"); |
| 464 | else |
| 465 | btrfs_info(info, "setting datasum"); |
| 466 | } |
| 467 | btrfs_clear_opt(info->mount_opt, NODATACOW); |
| 468 | btrfs_clear_opt(info->mount_opt, NODATASUM); |
| 469 | break; |
| 470 | case Opt_nodatacow: |
| 471 | if (!btrfs_test_opt(info, NODATACOW)) { |
| 472 | if (!btrfs_test_opt(info, COMPRESS) || |
| 473 | !btrfs_test_opt(info, FORCE_COMPRESS)) { |
| 474 | btrfs_info(info, |
| 475 | "setting nodatacow, compression disabled"); |
| 476 | } else { |
| 477 | btrfs_info(info, "setting nodatacow"); |
| 478 | } |
| 479 | } |
| 480 | btrfs_clear_opt(info->mount_opt, COMPRESS); |
| 481 | btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); |
| 482 | btrfs_set_opt(info->mount_opt, NODATACOW); |
| 483 | btrfs_set_opt(info->mount_opt, NODATASUM); |
| 484 | break; |
| 485 | case Opt_datacow: |
| 486 | btrfs_clear_and_info(info, NODATACOW, |
| 487 | "setting datacow"); |
| 488 | break; |
| 489 | case Opt_compress_force: |
| 490 | case Opt_compress_force_type: |
| 491 | compress_force = true; |
| 492 | /* Fallthrough */ |
| 493 | case Opt_compress: |
| 494 | case Opt_compress_type: |
| 495 | saved_compress_type = btrfs_test_opt(info, |
| 496 | COMPRESS) ? |
| 497 | info->compress_type : BTRFS_COMPRESS_NONE; |
| 498 | saved_compress_force = |
| 499 | btrfs_test_opt(info, FORCE_COMPRESS); |
| 500 | if (token == Opt_compress || |
| 501 | token == Opt_compress_force || |
| 502 | strncmp(args[0].from, "zlib", 4) == 0) { |
| 503 | compress_type = "zlib"; |
| 504 | info->compress_type = BTRFS_COMPRESS_ZLIB; |
| 505 | btrfs_set_opt(info->mount_opt, COMPRESS); |
| 506 | btrfs_clear_opt(info->mount_opt, NODATACOW); |
| 507 | btrfs_clear_opt(info->mount_opt, NODATASUM); |
| 508 | no_compress = 0; |
| 509 | } else if (strncmp(args[0].from, "lzo", 3) == 0) { |
| 510 | compress_type = "lzo"; |
| 511 | info->compress_type = BTRFS_COMPRESS_LZO; |
| 512 | btrfs_set_opt(info->mount_opt, COMPRESS); |
| 513 | btrfs_clear_opt(info->mount_opt, NODATACOW); |
| 514 | btrfs_clear_opt(info->mount_opt, NODATASUM); |
| 515 | btrfs_set_fs_incompat(info, COMPRESS_LZO); |
| 516 | no_compress = 0; |
| 517 | } else if (strcmp(args[0].from, "zstd") == 0) { |
| 518 | compress_type = "zstd"; |
| 519 | info->compress_type = BTRFS_COMPRESS_ZSTD; |
| 520 | btrfs_set_opt(info->mount_opt, COMPRESS); |
| 521 | btrfs_clear_opt(info->mount_opt, NODATACOW); |
| 522 | btrfs_clear_opt(info->mount_opt, NODATASUM); |
| 523 | btrfs_set_fs_incompat(info, COMPRESS_ZSTD); |
| 524 | no_compress = 0; |
| 525 | } else if (strncmp(args[0].from, "no", 2) == 0) { |
| 526 | compress_type = "no"; |
| 527 | btrfs_clear_opt(info->mount_opt, COMPRESS); |
| 528 | btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); |
| 529 | compress_force = false; |
| 530 | no_compress++; |
| 531 | } else { |
| 532 | ret = -EINVAL; |
| 533 | goto out; |
| 534 | } |
| 535 | |
| 536 | if (compress_force) { |
| 537 | btrfs_set_opt(info->mount_opt, FORCE_COMPRESS); |
| 538 | } else { |
| 539 | /* |
| 540 | * If we remount from compress-force=xxx to |
| 541 | * compress=xxx, we need clear FORCE_COMPRESS |
| 542 | * flag, otherwise, there is no way for users |
| 543 | * to disable forcible compression separately. |
| 544 | */ |
| 545 | btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); |
| 546 | } |
| 547 | if ((btrfs_test_opt(info, COMPRESS) && |
| 548 | (info->compress_type != saved_compress_type || |
| 549 | compress_force != saved_compress_force)) || |
| 550 | (!btrfs_test_opt(info, COMPRESS) && |
| 551 | no_compress == 1)) { |
| 552 | btrfs_info(info, "%s %s compression", |
| 553 | (compress_force) ? "force" : "use", |
| 554 | compress_type); |
| 555 | } |
| 556 | compress_force = false; |
| 557 | break; |
| 558 | case Opt_ssd: |
| 559 | btrfs_set_and_info(info, SSD, |
| 560 | "enabling ssd optimizations"); |
| 561 | btrfs_clear_opt(info->mount_opt, NOSSD); |
| 562 | break; |
| 563 | case Opt_ssd_spread: |
| 564 | btrfs_set_and_info(info, SSD, |
| 565 | "enabling ssd optimizations"); |
| 566 | btrfs_set_and_info(info, SSD_SPREAD, |
| 567 | "using spread ssd allocation scheme"); |
| 568 | btrfs_clear_opt(info->mount_opt, NOSSD); |
| 569 | break; |
| 570 | case Opt_nossd: |
| 571 | btrfs_set_opt(info->mount_opt, NOSSD); |
| 572 | btrfs_clear_and_info(info, SSD, |
| 573 | "not using ssd optimizations"); |
| 574 | btrfs_clear_and_info(info, SSD_SPREAD, |
| 575 | "not using spread ssd allocation scheme"); |
| 576 | break; |
| 577 | case Opt_barrier: |
| 578 | btrfs_clear_and_info(info, NOBARRIER, |
| 579 | "turning on barriers"); |
| 580 | break; |
| 581 | case Opt_nobarrier: |
| 582 | btrfs_set_and_info(info, NOBARRIER, |
| 583 | "turning off barriers"); |
| 584 | break; |
| 585 | case Opt_thread_pool: |
| 586 | ret = match_int(&args[0], &intarg); |
| 587 | if (ret) { |
| 588 | goto out; |
| 589 | } else if (intarg > 0) { |
| 590 | info->thread_pool_size = intarg; |
| 591 | } else { |
| 592 | ret = -EINVAL; |
| 593 | goto out; |
| 594 | } |
| 595 | break; |
| 596 | case Opt_max_inline: |
| 597 | num = match_strdup(&args[0]); |
| 598 | if (num) { |
| 599 | info->max_inline = memparse(num, NULL); |
| 600 | kfree(num); |
| 601 | |
| 602 | if (info->max_inline) { |
| 603 | info->max_inline = min_t(u64, |
| 604 | info->max_inline, |
| 605 | info->sectorsize); |
| 606 | } |
| 607 | btrfs_info(info, "max_inline at %llu", |
| 608 | info->max_inline); |
| 609 | } else { |
| 610 | ret = -ENOMEM; |
| 611 | goto out; |
| 612 | } |
| 613 | break; |
| 614 | case Opt_alloc_start: |
| 615 | btrfs_info(info, |
| 616 | "option alloc_start is obsolete, ignored"); |
| 617 | break; |
| 618 | case Opt_acl: |
| 619 | #ifdef CONFIG_BTRFS_FS_POSIX_ACL |
| 620 | info->sb->s_flags |= MS_POSIXACL; |
| 621 | break; |
| 622 | #else |
| 623 | btrfs_err(info, "support for ACL not compiled in!"); |
| 624 | ret = -EINVAL; |
| 625 | goto out; |
| 626 | #endif |
| 627 | case Opt_noacl: |
| 628 | info->sb->s_flags &= ~MS_POSIXACL; |
| 629 | break; |
| 630 | case Opt_notreelog: |
| 631 | btrfs_set_and_info(info, NOTREELOG, |
| 632 | "disabling tree log"); |
| 633 | break; |
| 634 | case Opt_treelog: |
| 635 | btrfs_clear_and_info(info, NOTREELOG, |
| 636 | "enabling tree log"); |
| 637 | break; |
| 638 | case Opt_norecovery: |
| 639 | case Opt_nologreplay: |
| 640 | btrfs_set_and_info(info, NOLOGREPLAY, |
| 641 | "disabling log replay at mount time"); |
| 642 | break; |
| 643 | case Opt_flushoncommit: |
| 644 | btrfs_set_and_info(info, FLUSHONCOMMIT, |
| 645 | "turning on flush-on-commit"); |
| 646 | break; |
| 647 | case Opt_noflushoncommit: |
| 648 | btrfs_clear_and_info(info, FLUSHONCOMMIT, |
| 649 | "turning off flush-on-commit"); |
| 650 | break; |
| 651 | case Opt_ratio: |
| 652 | ret = match_int(&args[0], &intarg); |
| 653 | if (ret) { |
| 654 | goto out; |
| 655 | } else if (intarg >= 0) { |
| 656 | info->metadata_ratio = intarg; |
| 657 | btrfs_info(info, "metadata ratio %d", |
| 658 | info->metadata_ratio); |
| 659 | } else { |
| 660 | ret = -EINVAL; |
| 661 | goto out; |
| 662 | } |
| 663 | break; |
| 664 | case Opt_discard: |
| 665 | btrfs_set_and_info(info, DISCARD, |
| 666 | "turning on discard"); |
| 667 | break; |
| 668 | case Opt_nodiscard: |
| 669 | btrfs_clear_and_info(info, DISCARD, |
| 670 | "turning off discard"); |
| 671 | break; |
| 672 | case Opt_space_cache: |
| 673 | case Opt_space_cache_version: |
| 674 | if (token == Opt_space_cache || |
| 675 | strcmp(args[0].from, "v1") == 0) { |
| 676 | btrfs_clear_opt(info->mount_opt, |
| 677 | FREE_SPACE_TREE); |
| 678 | btrfs_set_and_info(info, SPACE_CACHE, |
| 679 | "enabling disk space caching"); |
| 680 | } else if (strcmp(args[0].from, "v2") == 0) { |
| 681 | btrfs_clear_opt(info->mount_opt, |
| 682 | SPACE_CACHE); |
| 683 | btrfs_set_and_info(info, FREE_SPACE_TREE, |
| 684 | "enabling free space tree"); |
| 685 | } else { |
| 686 | ret = -EINVAL; |
| 687 | goto out; |
| 688 | } |
| 689 | break; |
| 690 | case Opt_rescan_uuid_tree: |
| 691 | btrfs_set_opt(info->mount_opt, RESCAN_UUID_TREE); |
| 692 | break; |
| 693 | case Opt_no_space_cache: |
| 694 | if (btrfs_test_opt(info, SPACE_CACHE)) { |
| 695 | btrfs_clear_and_info(info, SPACE_CACHE, |
| 696 | "disabling disk space caching"); |
| 697 | } |
| 698 | if (btrfs_test_opt(info, FREE_SPACE_TREE)) { |
| 699 | btrfs_clear_and_info(info, FREE_SPACE_TREE, |
| 700 | "disabling free space tree"); |
| 701 | } |
| 702 | break; |
| 703 | case Opt_inode_cache: |
| 704 | btrfs_set_pending_and_info(info, INODE_MAP_CACHE, |
| 705 | "enabling inode map caching"); |
| 706 | break; |
| 707 | case Opt_noinode_cache: |
| 708 | btrfs_clear_pending_and_info(info, INODE_MAP_CACHE, |
| 709 | "disabling inode map caching"); |
| 710 | break; |
| 711 | case Opt_clear_cache: |
| 712 | btrfs_set_and_info(info, CLEAR_CACHE, |
| 713 | "force clearing of disk cache"); |
| 714 | break; |
| 715 | case Opt_user_subvol_rm_allowed: |
| 716 | btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); |
| 717 | break; |
| 718 | case Opt_enospc_debug: |
| 719 | btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG); |
| 720 | break; |
| 721 | case Opt_noenospc_debug: |
| 722 | btrfs_clear_opt(info->mount_opt, ENOSPC_DEBUG); |
| 723 | break; |
| 724 | case Opt_defrag: |
| 725 | btrfs_set_and_info(info, AUTO_DEFRAG, |
| 726 | "enabling auto defrag"); |
| 727 | break; |
| 728 | case Opt_nodefrag: |
| 729 | btrfs_clear_and_info(info, AUTO_DEFRAG, |
| 730 | "disabling auto defrag"); |
| 731 | break; |
| 732 | case Opt_recovery: |
| 733 | btrfs_warn(info, |
| 734 | "'recovery' is deprecated, use 'usebackuproot' instead"); |
| 735 | case Opt_usebackuproot: |
| 736 | btrfs_info(info, |
| 737 | "trying to use backup root at mount time"); |
| 738 | btrfs_set_opt(info->mount_opt, USEBACKUPROOT); |
| 739 | break; |
| 740 | case Opt_skip_balance: |
| 741 | btrfs_set_opt(info->mount_opt, SKIP_BALANCE); |
| 742 | break; |
| 743 | #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY |
| 744 | case Opt_check_integrity_including_extent_data: |
| 745 | btrfs_info(info, |
| 746 | "enabling check integrity including extent data"); |
| 747 | btrfs_set_opt(info->mount_opt, |
| 748 | CHECK_INTEGRITY_INCLUDING_EXTENT_DATA); |
| 749 | btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY); |
| 750 | break; |
| 751 | case Opt_check_integrity: |
| 752 | btrfs_info(info, "enabling check integrity"); |
| 753 | btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY); |
| 754 | break; |
| 755 | case Opt_check_integrity_print_mask: |
| 756 | ret = match_int(&args[0], &intarg); |
| 757 | if (ret) { |
| 758 | goto out; |
| 759 | } else if (intarg >= 0) { |
| 760 | info->check_integrity_print_mask = intarg; |
| 761 | btrfs_info(info, |
| 762 | "check_integrity_print_mask 0x%x", |
| 763 | info->check_integrity_print_mask); |
| 764 | } else { |
| 765 | ret = -EINVAL; |
| 766 | goto out; |
| 767 | } |
| 768 | break; |
| 769 | #else |
| 770 | case Opt_check_integrity_including_extent_data: |
| 771 | case Opt_check_integrity: |
| 772 | case Opt_check_integrity_print_mask: |
| 773 | btrfs_err(info, |
| 774 | "support for check_integrity* not compiled in!"); |
| 775 | ret = -EINVAL; |
| 776 | goto out; |
| 777 | #endif |
| 778 | case Opt_fatal_errors: |
| 779 | if (strcmp(args[0].from, "panic") == 0) |
| 780 | btrfs_set_opt(info->mount_opt, |
| 781 | PANIC_ON_FATAL_ERROR); |
| 782 | else if (strcmp(args[0].from, "bug") == 0) |
| 783 | btrfs_clear_opt(info->mount_opt, |
| 784 | PANIC_ON_FATAL_ERROR); |
| 785 | else { |
| 786 | ret = -EINVAL; |
| 787 | goto out; |
| 788 | } |
| 789 | break; |
| 790 | case Opt_commit_interval: |
| 791 | intarg = 0; |
| 792 | ret = match_int(&args[0], &intarg); |
| 793 | if (ret < 0) { |
| 794 | btrfs_err(info, "invalid commit interval"); |
| 795 | ret = -EINVAL; |
| 796 | goto out; |
| 797 | } |
| 798 | if (intarg > 0) { |
| 799 | if (intarg > 300) { |
| 800 | btrfs_warn(info, |
| 801 | "excessive commit interval %d", |
| 802 | intarg); |
| 803 | } |
| 804 | info->commit_interval = intarg; |
| 805 | } else { |
| 806 | btrfs_info(info, |
| 807 | "using default commit interval %ds", |
| 808 | BTRFS_DEFAULT_COMMIT_INTERVAL); |
| 809 | info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL; |
| 810 | } |
| 811 | break; |
| 812 | #ifdef CONFIG_BTRFS_DEBUG |
| 813 | case Opt_fragment_all: |
| 814 | btrfs_info(info, "fragmenting all space"); |
| 815 | btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); |
| 816 | btrfs_set_opt(info->mount_opt, FRAGMENT_METADATA); |
| 817 | break; |
| 818 | case Opt_fragment_metadata: |
| 819 | btrfs_info(info, "fragmenting metadata"); |
| 820 | btrfs_set_opt(info->mount_opt, |
| 821 | FRAGMENT_METADATA); |
| 822 | break; |
| 823 | case Opt_fragment_data: |
| 824 | btrfs_info(info, "fragmenting data"); |
| 825 | btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); |
| 826 | break; |
| 827 | #endif |
| 828 | case Opt_err: |
| 829 | btrfs_info(info, "unrecognized mount option '%s'", p); |
| 830 | ret = -EINVAL; |
| 831 | goto out; |
| 832 | default: |
| 833 | break; |
| 834 | } |
| 835 | } |
| 836 | check: |
| 837 | /* |
| 838 | * Extra check for current option against current flag |
| 839 | */ |
| 840 | if (btrfs_test_opt(info, NOLOGREPLAY) && !(new_flags & MS_RDONLY)) { |
| 841 | btrfs_err(info, |
| 842 | "nologreplay must be used with ro mount option"); |
| 843 | ret = -EINVAL; |
| 844 | } |
| 845 | out: |
| 846 | if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) && |
| 847 | !btrfs_test_opt(info, FREE_SPACE_TREE) && |
| 848 | !btrfs_test_opt(info, CLEAR_CACHE)) { |
| 849 | btrfs_err(info, "cannot disable free space tree"); |
| 850 | ret = -EINVAL; |
| 851 | |
| 852 | } |
| 853 | if (!ret && btrfs_test_opt(info, SPACE_CACHE)) |
| 854 | btrfs_info(info, "disk space caching is enabled"); |
| 855 | if (!ret && btrfs_test_opt(info, FREE_SPACE_TREE)) |
| 856 | btrfs_info(info, "using free space tree"); |
| 857 | kfree(orig); |
| 858 | return ret; |
| 859 | } |
| 860 | |
| 861 | /* |
| 862 | * Parse mount options that are required early in the mount process. |
| 863 | * |
| 864 | * All other options will be parsed on much later in the mount process and |
| 865 | * only when we need to allocate a new super block. |
| 866 | */ |
| 867 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
| 868 | void *holder, char **subvol_name, u64 *subvol_objectid, |
| 869 | struct btrfs_fs_devices **fs_devices) |
| 870 | { |
| 871 | substring_t args[MAX_OPT_ARGS]; |
| 872 | char *device_name, *opts, *orig, *p; |
| 873 | char *num = NULL; |
| 874 | int error = 0; |
| 875 | |
| 876 | if (!options) |
| 877 | return 0; |
| 878 | |
| 879 | /* |
| 880 | * strsep changes the string, duplicate it because parse_options |
| 881 | * gets called twice |
| 882 | */ |
| 883 | opts = kstrdup(options, GFP_KERNEL); |
| 884 | if (!opts) |
| 885 | return -ENOMEM; |
| 886 | orig = opts; |
| 887 | |
| 888 | while ((p = strsep(&opts, ",")) != NULL) { |
| 889 | int token; |
| 890 | if (!*p) |
| 891 | continue; |
| 892 | |
| 893 | token = match_token(p, tokens, args); |
| 894 | switch (token) { |
| 895 | case Opt_subvol: |
| 896 | kfree(*subvol_name); |
| 897 | *subvol_name = match_strdup(&args[0]); |
| 898 | if (!*subvol_name) { |
| 899 | error = -ENOMEM; |
| 900 | goto out; |
| 901 | } |
| 902 | break; |
| 903 | case Opt_subvolid: |
| 904 | num = match_strdup(&args[0]); |
| 905 | if (num) { |
| 906 | *subvol_objectid = memparse(num, NULL); |
| 907 | kfree(num); |
| 908 | /* we want the original fs_tree */ |
| 909 | if (!*subvol_objectid) |
| 910 | *subvol_objectid = |
| 911 | BTRFS_FS_TREE_OBJECTID; |
| 912 | } else { |
| 913 | error = -EINVAL; |
| 914 | goto out; |
| 915 | } |
| 916 | break; |
| 917 | case Opt_subvolrootid: |
| 918 | pr_warn("BTRFS: 'subvolrootid' mount option is deprecated and has no effect\n"); |
| 919 | break; |
| 920 | case Opt_device: |
| 921 | device_name = match_strdup(&args[0]); |
| 922 | if (!device_name) { |
| 923 | error = -ENOMEM; |
| 924 | goto out; |
| 925 | } |
| 926 | error = btrfs_scan_one_device(device_name, |
| 927 | flags, holder, fs_devices); |
| 928 | kfree(device_name); |
| 929 | if (error) |
| 930 | goto out; |
| 931 | break; |
| 932 | default: |
| 933 | break; |
| 934 | } |
| 935 | } |
| 936 | |
| 937 | out: |
| 938 | kfree(orig); |
| 939 | return error; |
| 940 | } |
| 941 | |
| 942 | static char *get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, |
| 943 | u64 subvol_objectid) |
| 944 | { |
| 945 | struct btrfs_root *root = fs_info->tree_root; |
| 946 | struct btrfs_root *fs_root; |
| 947 | struct btrfs_root_ref *root_ref; |
| 948 | struct btrfs_inode_ref *inode_ref; |
| 949 | struct btrfs_key key; |
| 950 | struct btrfs_path *path = NULL; |
| 951 | char *name = NULL, *ptr; |
| 952 | u64 dirid; |
| 953 | int len; |
| 954 | int ret; |
| 955 | |
| 956 | path = btrfs_alloc_path(); |
| 957 | if (!path) { |
| 958 | ret = -ENOMEM; |
| 959 | goto err; |
| 960 | } |
| 961 | path->leave_spinning = 1; |
| 962 | |
| 963 | name = kmalloc(PATH_MAX, GFP_KERNEL); |
| 964 | if (!name) { |
| 965 | ret = -ENOMEM; |
| 966 | goto err; |
| 967 | } |
| 968 | ptr = name + PATH_MAX - 1; |
| 969 | ptr[0] = '\0'; |
| 970 | |
| 971 | /* |
| 972 | * Walk up the subvolume trees in the tree of tree roots by root |
| 973 | * backrefs until we hit the top-level subvolume. |
| 974 | */ |
| 975 | while (subvol_objectid != BTRFS_FS_TREE_OBJECTID) { |
| 976 | key.objectid = subvol_objectid; |
| 977 | key.type = BTRFS_ROOT_BACKREF_KEY; |
| 978 | key.offset = (u64)-1; |
| 979 | |
| 980 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 981 | if (ret < 0) { |
| 982 | goto err; |
| 983 | } else if (ret > 0) { |
| 984 | ret = btrfs_previous_item(root, path, subvol_objectid, |
| 985 | BTRFS_ROOT_BACKREF_KEY); |
| 986 | if (ret < 0) { |
| 987 | goto err; |
| 988 | } else if (ret > 0) { |
| 989 | ret = -ENOENT; |
| 990 | goto err; |
| 991 | } |
| 992 | } |
| 993 | |
| 994 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); |
| 995 | subvol_objectid = key.offset; |
| 996 | |
| 997 | root_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| 998 | struct btrfs_root_ref); |
| 999 | len = btrfs_root_ref_name_len(path->nodes[0], root_ref); |
| 1000 | ptr -= len + 1; |
| 1001 | if (ptr < name) { |
| 1002 | ret = -ENAMETOOLONG; |
| 1003 | goto err; |
| 1004 | } |
| 1005 | read_extent_buffer(path->nodes[0], ptr + 1, |
| 1006 | (unsigned long)(root_ref + 1), len); |
| 1007 | ptr[0] = '/'; |
| 1008 | dirid = btrfs_root_ref_dirid(path->nodes[0], root_ref); |
| 1009 | btrfs_release_path(path); |
| 1010 | |
| 1011 | key.objectid = subvol_objectid; |
| 1012 | key.type = BTRFS_ROOT_ITEM_KEY; |
| 1013 | key.offset = (u64)-1; |
| 1014 | fs_root = btrfs_read_fs_root_no_name(fs_info, &key); |
| 1015 | if (IS_ERR(fs_root)) { |
| 1016 | ret = PTR_ERR(fs_root); |
| 1017 | goto err; |
| 1018 | } |
| 1019 | |
| 1020 | /* |
| 1021 | * Walk up the filesystem tree by inode refs until we hit the |
| 1022 | * root directory. |
| 1023 | */ |
| 1024 | while (dirid != BTRFS_FIRST_FREE_OBJECTID) { |
| 1025 | key.objectid = dirid; |
| 1026 | key.type = BTRFS_INODE_REF_KEY; |
| 1027 | key.offset = (u64)-1; |
| 1028 | |
| 1029 | ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0); |
| 1030 | if (ret < 0) { |
| 1031 | goto err; |
| 1032 | } else if (ret > 0) { |
| 1033 | ret = btrfs_previous_item(fs_root, path, dirid, |
| 1034 | BTRFS_INODE_REF_KEY); |
| 1035 | if (ret < 0) { |
| 1036 | goto err; |
| 1037 | } else if (ret > 0) { |
| 1038 | ret = -ENOENT; |
| 1039 | goto err; |
| 1040 | } |
| 1041 | } |
| 1042 | |
| 1043 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); |
| 1044 | dirid = key.offset; |
| 1045 | |
| 1046 | inode_ref = btrfs_item_ptr(path->nodes[0], |
| 1047 | path->slots[0], |
| 1048 | struct btrfs_inode_ref); |
| 1049 | len = btrfs_inode_ref_name_len(path->nodes[0], |
| 1050 | inode_ref); |
| 1051 | ptr -= len + 1; |
| 1052 | if (ptr < name) { |
| 1053 | ret = -ENAMETOOLONG; |
| 1054 | goto err; |
| 1055 | } |
| 1056 | read_extent_buffer(path->nodes[0], ptr + 1, |
| 1057 | (unsigned long)(inode_ref + 1), len); |
| 1058 | ptr[0] = '/'; |
| 1059 | btrfs_release_path(path); |
| 1060 | } |
| 1061 | } |
| 1062 | |
| 1063 | btrfs_free_path(path); |
| 1064 | if (ptr == name + PATH_MAX - 1) { |
| 1065 | name[0] = '/'; |
| 1066 | name[1] = '\0'; |
| 1067 | } else { |
| 1068 | memmove(name, ptr, name + PATH_MAX - ptr); |
| 1069 | } |
| 1070 | return name; |
| 1071 | |
| 1072 | err: |
| 1073 | btrfs_free_path(path); |
| 1074 | kfree(name); |
| 1075 | return ERR_PTR(ret); |
| 1076 | } |
| 1077 | |
| 1078 | static int get_default_subvol_objectid(struct btrfs_fs_info *fs_info, u64 *objectid) |
| 1079 | { |
| 1080 | struct btrfs_root *root = fs_info->tree_root; |
| 1081 | struct btrfs_dir_item *di; |
| 1082 | struct btrfs_path *path; |
| 1083 | struct btrfs_key location; |
| 1084 | u64 dir_id; |
| 1085 | |
| 1086 | path = btrfs_alloc_path(); |
| 1087 | if (!path) |
| 1088 | return -ENOMEM; |
| 1089 | path->leave_spinning = 1; |
| 1090 | |
| 1091 | /* |
| 1092 | * Find the "default" dir item which points to the root item that we |
| 1093 | * will mount by default if we haven't been given a specific subvolume |
| 1094 | * to mount. |
| 1095 | */ |
| 1096 | dir_id = btrfs_super_root_dir(fs_info->super_copy); |
| 1097 | di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0); |
| 1098 | if (IS_ERR(di)) { |
| 1099 | btrfs_free_path(path); |
| 1100 | return PTR_ERR(di); |
| 1101 | } |
| 1102 | if (!di) { |
| 1103 | /* |
| 1104 | * Ok the default dir item isn't there. This is weird since |
| 1105 | * it's always been there, but don't freak out, just try and |
| 1106 | * mount the top-level subvolume. |
| 1107 | */ |
| 1108 | btrfs_free_path(path); |
| 1109 | *objectid = BTRFS_FS_TREE_OBJECTID; |
| 1110 | return 0; |
| 1111 | } |
| 1112 | |
| 1113 | btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); |
| 1114 | btrfs_free_path(path); |
| 1115 | *objectid = location.objectid; |
| 1116 | return 0; |
| 1117 | } |
| 1118 | |
| 1119 | static int btrfs_fill_super(struct super_block *sb, |
| 1120 | struct btrfs_fs_devices *fs_devices, |
| 1121 | void *data) |
| 1122 | { |
| 1123 | struct inode *inode; |
| 1124 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| 1125 | struct btrfs_key key; |
| 1126 | int err; |
| 1127 | |
| 1128 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
| 1129 | sb->s_magic = BTRFS_SUPER_MAGIC; |
| 1130 | sb->s_op = &btrfs_super_ops; |
| 1131 | sb->s_d_op = &btrfs_dentry_operations; |
| 1132 | sb->s_export_op = &btrfs_export_ops; |
| 1133 | sb->s_xattr = btrfs_xattr_handlers; |
| 1134 | sb->s_time_gran = 1; |
| 1135 | #ifdef CONFIG_BTRFS_FS_POSIX_ACL |
| 1136 | sb->s_flags |= MS_POSIXACL; |
| 1137 | #endif |
| 1138 | sb->s_flags |= SB_I_VERSION; |
| 1139 | sb->s_iflags |= SB_I_CGROUPWB; |
| 1140 | |
| 1141 | err = super_setup_bdi(sb); |
| 1142 | if (err) { |
| 1143 | btrfs_err(fs_info, "super_setup_bdi failed"); |
| 1144 | return err; |
| 1145 | } |
| 1146 | |
| 1147 | err = open_ctree(sb, fs_devices, (char *)data); |
| 1148 | if (err) { |
| 1149 | btrfs_err(fs_info, "open_ctree failed"); |
| 1150 | return err; |
| 1151 | } |
| 1152 | |
| 1153 | key.objectid = BTRFS_FIRST_FREE_OBJECTID; |
| 1154 | key.type = BTRFS_INODE_ITEM_KEY; |
| 1155 | key.offset = 0; |
| 1156 | inode = btrfs_iget(sb, &key, fs_info->fs_root, NULL); |
| 1157 | if (IS_ERR(inode)) { |
| 1158 | err = PTR_ERR(inode); |
| 1159 | goto fail_close; |
| 1160 | } |
| 1161 | |
| 1162 | sb->s_root = d_make_root(inode); |
| 1163 | if (!sb->s_root) { |
| 1164 | err = -ENOMEM; |
| 1165 | goto fail_close; |
| 1166 | } |
| 1167 | |
| 1168 | cleancache_init_fs(sb); |
| 1169 | sb->s_flags |= MS_ACTIVE; |
| 1170 | return 0; |
| 1171 | |
| 1172 | fail_close: |
| 1173 | close_ctree(fs_info); |
| 1174 | return err; |
| 1175 | } |
| 1176 | |
| 1177 | int btrfs_sync_fs(struct super_block *sb, int wait) |
| 1178 | { |
| 1179 | struct btrfs_trans_handle *trans; |
| 1180 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| 1181 | struct btrfs_root *root = fs_info->tree_root; |
| 1182 | |
| 1183 | trace_btrfs_sync_fs(fs_info, wait); |
| 1184 | |
| 1185 | if (!wait) { |
| 1186 | filemap_flush(fs_info->btree_inode->i_mapping); |
| 1187 | return 0; |
| 1188 | } |
| 1189 | |
| 1190 | btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); |
| 1191 | |
| 1192 | trans = btrfs_attach_transaction_barrier(root); |
| 1193 | if (IS_ERR(trans)) { |
| 1194 | /* no transaction, don't bother */ |
| 1195 | if (PTR_ERR(trans) == -ENOENT) { |
| 1196 | /* |
| 1197 | * Exit unless we have some pending changes |
| 1198 | * that need to go through commit |
| 1199 | */ |
| 1200 | if (fs_info->pending_changes == 0) |
| 1201 | return 0; |
| 1202 | /* |
| 1203 | * A non-blocking test if the fs is frozen. We must not |
| 1204 | * start a new transaction here otherwise a deadlock |
| 1205 | * happens. The pending operations are delayed to the |
| 1206 | * next commit after thawing. |
| 1207 | */ |
| 1208 | if (__sb_start_write(sb, SB_FREEZE_WRITE, false)) |
| 1209 | __sb_end_write(sb, SB_FREEZE_WRITE); |
| 1210 | else |
| 1211 | return 0; |
| 1212 | trans = btrfs_start_transaction(root, 0); |
| 1213 | } |
| 1214 | if (IS_ERR(trans)) |
| 1215 | return PTR_ERR(trans); |
| 1216 | } |
| 1217 | return btrfs_commit_transaction(trans); |
| 1218 | } |
| 1219 | |
| 1220 | static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) |
| 1221 | { |
| 1222 | struct btrfs_fs_info *info = btrfs_sb(dentry->d_sb); |
| 1223 | char *compress_type; |
| 1224 | |
| 1225 | if (btrfs_test_opt(info, DEGRADED)) |
| 1226 | seq_puts(seq, ",degraded"); |
| 1227 | if (btrfs_test_opt(info, NODATASUM)) |
| 1228 | seq_puts(seq, ",nodatasum"); |
| 1229 | if (btrfs_test_opt(info, NODATACOW)) |
| 1230 | seq_puts(seq, ",nodatacow"); |
| 1231 | if (btrfs_test_opt(info, NOBARRIER)) |
| 1232 | seq_puts(seq, ",nobarrier"); |
| 1233 | if (info->max_inline != BTRFS_DEFAULT_MAX_INLINE) |
| 1234 | seq_printf(seq, ",max_inline=%llu", info->max_inline); |
| 1235 | if (info->thread_pool_size != min_t(unsigned long, |
| 1236 | num_online_cpus() + 2, 8)) |
| 1237 | seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); |
| 1238 | if (btrfs_test_opt(info, COMPRESS)) { |
| 1239 | if (info->compress_type == BTRFS_COMPRESS_ZLIB) |
| 1240 | compress_type = "zlib"; |
| 1241 | else if (info->compress_type == BTRFS_COMPRESS_LZO) |
| 1242 | compress_type = "lzo"; |
| 1243 | else |
| 1244 | compress_type = "zstd"; |
| 1245 | if (btrfs_test_opt(info, FORCE_COMPRESS)) |
| 1246 | seq_printf(seq, ",compress-force=%s", compress_type); |
| 1247 | else |
| 1248 | seq_printf(seq, ",compress=%s", compress_type); |
| 1249 | } |
| 1250 | if (btrfs_test_opt(info, NOSSD)) |
| 1251 | seq_puts(seq, ",nossd"); |
| 1252 | if (btrfs_test_opt(info, SSD_SPREAD)) |
| 1253 | seq_puts(seq, ",ssd_spread"); |
| 1254 | else if (btrfs_test_opt(info, SSD)) |
| 1255 | seq_puts(seq, ",ssd"); |
| 1256 | if (btrfs_test_opt(info, NOTREELOG)) |
| 1257 | seq_puts(seq, ",notreelog"); |
| 1258 | if (btrfs_test_opt(info, NOLOGREPLAY)) |
| 1259 | seq_puts(seq, ",nologreplay"); |
| 1260 | if (btrfs_test_opt(info, FLUSHONCOMMIT)) |
| 1261 | seq_puts(seq, ",flushoncommit"); |
| 1262 | if (btrfs_test_opt(info, DISCARD)) |
| 1263 | seq_puts(seq, ",discard"); |
| 1264 | if (!(info->sb->s_flags & MS_POSIXACL)) |
| 1265 | seq_puts(seq, ",noacl"); |
| 1266 | if (btrfs_test_opt(info, SPACE_CACHE)) |
| 1267 | seq_puts(seq, ",space_cache"); |
| 1268 | else if (btrfs_test_opt(info, FREE_SPACE_TREE)) |
| 1269 | seq_puts(seq, ",space_cache=v2"); |
| 1270 | else |
| 1271 | seq_puts(seq, ",nospace_cache"); |
| 1272 | if (btrfs_test_opt(info, RESCAN_UUID_TREE)) |
| 1273 | seq_puts(seq, ",rescan_uuid_tree"); |
| 1274 | if (btrfs_test_opt(info, CLEAR_CACHE)) |
| 1275 | seq_puts(seq, ",clear_cache"); |
| 1276 | if (btrfs_test_opt(info, USER_SUBVOL_RM_ALLOWED)) |
| 1277 | seq_puts(seq, ",user_subvol_rm_allowed"); |
| 1278 | if (btrfs_test_opt(info, ENOSPC_DEBUG)) |
| 1279 | seq_puts(seq, ",enospc_debug"); |
| 1280 | if (btrfs_test_opt(info, AUTO_DEFRAG)) |
| 1281 | seq_puts(seq, ",autodefrag"); |
| 1282 | if (btrfs_test_opt(info, INODE_MAP_CACHE)) |
| 1283 | seq_puts(seq, ",inode_cache"); |
| 1284 | if (btrfs_test_opt(info, SKIP_BALANCE)) |
| 1285 | seq_puts(seq, ",skip_balance"); |
| 1286 | #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY |
| 1287 | if (btrfs_test_opt(info, CHECK_INTEGRITY_INCLUDING_EXTENT_DATA)) |
| 1288 | seq_puts(seq, ",check_int_data"); |
| 1289 | else if (btrfs_test_opt(info, CHECK_INTEGRITY)) |
| 1290 | seq_puts(seq, ",check_int"); |
| 1291 | if (info->check_integrity_print_mask) |
| 1292 | seq_printf(seq, ",check_int_print_mask=%d", |
| 1293 | info->check_integrity_print_mask); |
| 1294 | #endif |
| 1295 | if (info->metadata_ratio) |
| 1296 | seq_printf(seq, ",metadata_ratio=%d", |
| 1297 | info->metadata_ratio); |
| 1298 | if (btrfs_test_opt(info, PANIC_ON_FATAL_ERROR)) |
| 1299 | seq_puts(seq, ",fatal_errors=panic"); |
| 1300 | if (info->commit_interval != BTRFS_DEFAULT_COMMIT_INTERVAL) |
| 1301 | seq_printf(seq, ",commit=%d", info->commit_interval); |
| 1302 | #ifdef CONFIG_BTRFS_DEBUG |
| 1303 | if (btrfs_test_opt(info, FRAGMENT_DATA)) |
| 1304 | seq_puts(seq, ",fragment=data"); |
| 1305 | if (btrfs_test_opt(info, FRAGMENT_METADATA)) |
| 1306 | seq_puts(seq, ",fragment=metadata"); |
| 1307 | #endif |
| 1308 | seq_printf(seq, ",subvolid=%llu", |
| 1309 | BTRFS_I(d_inode(dentry))->root->root_key.objectid); |
| 1310 | seq_puts(seq, ",subvol="); |
| 1311 | seq_dentry(seq, dentry, " \t\n\\"); |
| 1312 | return 0; |
| 1313 | } |
| 1314 | |
| 1315 | static int btrfs_test_super(struct super_block *s, void *data) |
| 1316 | { |
| 1317 | struct btrfs_fs_info *p = data; |
| 1318 | struct btrfs_fs_info *fs_info = btrfs_sb(s); |
| 1319 | |
| 1320 | return fs_info->fs_devices == p->fs_devices; |
| 1321 | } |
| 1322 | |
| 1323 | static int btrfs_set_super(struct super_block *s, void *data) |
| 1324 | { |
| 1325 | int err = set_anon_super(s, data); |
| 1326 | if (!err) |
| 1327 | s->s_fs_info = data; |
| 1328 | return err; |
| 1329 | } |
| 1330 | |
| 1331 | /* |
| 1332 | * subvolumes are identified by ino 256 |
| 1333 | */ |
| 1334 | static inline int is_subvolume_inode(struct inode *inode) |
| 1335 | { |
| 1336 | if (inode && inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) |
| 1337 | return 1; |
| 1338 | return 0; |
| 1339 | } |
| 1340 | |
| 1341 | /* |
| 1342 | * This will add subvolid=0 to the argument string while removing any subvol= |
| 1343 | * and subvolid= arguments to make sure we get the top-level root for path |
| 1344 | * walking to the subvol we want. |
| 1345 | */ |
| 1346 | static char *setup_root_args(char *args) |
| 1347 | { |
| 1348 | char *buf, *dst, *sep; |
| 1349 | |
| 1350 | if (!args) |
| 1351 | return kstrdup("subvolid=0", GFP_KERNEL); |
| 1352 | |
| 1353 | /* The worst case is that we add ",subvolid=0" to the end. */ |
| 1354 | buf = dst = kmalloc(strlen(args) + strlen(",subvolid=0") + 1, |
| 1355 | GFP_KERNEL); |
| 1356 | if (!buf) |
| 1357 | return NULL; |
| 1358 | |
| 1359 | while (1) { |
| 1360 | sep = strchrnul(args, ','); |
| 1361 | if (!strstarts(args, "subvol=") && |
| 1362 | !strstarts(args, "subvolid=")) { |
| 1363 | memcpy(dst, args, sep - args); |
| 1364 | dst += sep - args; |
| 1365 | *dst++ = ','; |
| 1366 | } |
| 1367 | if (*sep) |
| 1368 | args = sep + 1; |
| 1369 | else |
| 1370 | break; |
| 1371 | } |
| 1372 | strcpy(dst, "subvolid=0"); |
| 1373 | |
| 1374 | return buf; |
| 1375 | } |
| 1376 | |
| 1377 | static struct dentry *mount_subvol(const char *subvol_name, u64 subvol_objectid, |
| 1378 | int flags, const char *device_name, |
| 1379 | char *data) |
| 1380 | { |
| 1381 | struct dentry *root; |
| 1382 | struct vfsmount *mnt = NULL; |
| 1383 | char *newargs; |
| 1384 | int ret; |
| 1385 | |
| 1386 | newargs = setup_root_args(data); |
| 1387 | if (!newargs) { |
| 1388 | root = ERR_PTR(-ENOMEM); |
| 1389 | goto out; |
| 1390 | } |
| 1391 | |
| 1392 | mnt = vfs_kern_mount(&btrfs_fs_type, flags, device_name, newargs); |
| 1393 | if (PTR_ERR_OR_ZERO(mnt) == -EBUSY) { |
| 1394 | if (flags & MS_RDONLY) { |
| 1395 | mnt = vfs_kern_mount(&btrfs_fs_type, flags & ~MS_RDONLY, |
| 1396 | device_name, newargs); |
| 1397 | } else { |
| 1398 | mnt = vfs_kern_mount(&btrfs_fs_type, flags | MS_RDONLY, |
| 1399 | device_name, newargs); |
| 1400 | if (IS_ERR(mnt)) { |
| 1401 | root = ERR_CAST(mnt); |
| 1402 | mnt = NULL; |
| 1403 | goto out; |
| 1404 | } |
| 1405 | |
| 1406 | down_write(&mnt->mnt_sb->s_umount); |
| 1407 | ret = btrfs_remount(mnt->mnt_sb, &flags, NULL); |
| 1408 | up_write(&mnt->mnt_sb->s_umount); |
| 1409 | if (ret < 0) { |
| 1410 | root = ERR_PTR(ret); |
| 1411 | goto out; |
| 1412 | } |
| 1413 | } |
| 1414 | } |
| 1415 | if (IS_ERR(mnt)) { |
| 1416 | root = ERR_CAST(mnt); |
| 1417 | mnt = NULL; |
| 1418 | goto out; |
| 1419 | } |
| 1420 | |
| 1421 | if (!subvol_name) { |
| 1422 | if (!subvol_objectid) { |
| 1423 | ret = get_default_subvol_objectid(btrfs_sb(mnt->mnt_sb), |
| 1424 | &subvol_objectid); |
| 1425 | if (ret) { |
| 1426 | root = ERR_PTR(ret); |
| 1427 | goto out; |
| 1428 | } |
| 1429 | } |
| 1430 | subvol_name = get_subvol_name_from_objectid(btrfs_sb(mnt->mnt_sb), |
| 1431 | subvol_objectid); |
| 1432 | if (IS_ERR(subvol_name)) { |
| 1433 | root = ERR_CAST(subvol_name); |
| 1434 | subvol_name = NULL; |
| 1435 | goto out; |
| 1436 | } |
| 1437 | |
| 1438 | } |
| 1439 | |
| 1440 | root = mount_subtree(mnt, subvol_name); |
| 1441 | /* mount_subtree() drops our reference on the vfsmount. */ |
| 1442 | mnt = NULL; |
| 1443 | |
| 1444 | if (!IS_ERR(root)) { |
| 1445 | struct super_block *s = root->d_sb; |
| 1446 | struct btrfs_fs_info *fs_info = btrfs_sb(s); |
| 1447 | struct inode *root_inode = d_inode(root); |
| 1448 | u64 root_objectid = BTRFS_I(root_inode)->root->root_key.objectid; |
| 1449 | |
| 1450 | ret = 0; |
| 1451 | if (!is_subvolume_inode(root_inode)) { |
| 1452 | btrfs_err(fs_info, "'%s' is not a valid subvolume", |
| 1453 | subvol_name); |
| 1454 | ret = -EINVAL; |
| 1455 | } |
| 1456 | if (subvol_objectid && root_objectid != subvol_objectid) { |
| 1457 | /* |
| 1458 | * This will also catch a race condition where a |
| 1459 | * subvolume which was passed by ID is renamed and |
| 1460 | * another subvolume is renamed over the old location. |
| 1461 | */ |
| 1462 | btrfs_err(fs_info, |
| 1463 | "subvol '%s' does not match subvolid %llu", |
| 1464 | subvol_name, subvol_objectid); |
| 1465 | ret = -EINVAL; |
| 1466 | } |
| 1467 | if (ret) { |
| 1468 | dput(root); |
| 1469 | root = ERR_PTR(ret); |
| 1470 | deactivate_locked_super(s); |
| 1471 | } |
| 1472 | } |
| 1473 | |
| 1474 | out: |
| 1475 | mntput(mnt); |
| 1476 | kfree(newargs); |
| 1477 | kfree(subvol_name); |
| 1478 | return root; |
| 1479 | } |
| 1480 | |
| 1481 | static int parse_security_options(char *orig_opts, |
| 1482 | struct security_mnt_opts *sec_opts) |
| 1483 | { |
| 1484 | char *secdata = NULL; |
| 1485 | int ret = 0; |
| 1486 | |
| 1487 | secdata = alloc_secdata(); |
| 1488 | if (!secdata) |
| 1489 | return -ENOMEM; |
| 1490 | ret = security_sb_copy_data(orig_opts, secdata); |
| 1491 | if (ret) { |
| 1492 | free_secdata(secdata); |
| 1493 | return ret; |
| 1494 | } |
| 1495 | ret = security_sb_parse_opts_str(secdata, sec_opts); |
| 1496 | free_secdata(secdata); |
| 1497 | return ret; |
| 1498 | } |
| 1499 | |
| 1500 | static int setup_security_options(struct btrfs_fs_info *fs_info, |
| 1501 | struct super_block *sb, |
| 1502 | struct security_mnt_opts *sec_opts) |
| 1503 | { |
| 1504 | int ret = 0; |
| 1505 | |
| 1506 | /* |
| 1507 | * Call security_sb_set_mnt_opts() to check whether new sec_opts |
| 1508 | * is valid. |
| 1509 | */ |
| 1510 | ret = security_sb_set_mnt_opts(sb, sec_opts, 0, NULL); |
| 1511 | if (ret) |
| 1512 | return ret; |
| 1513 | |
| 1514 | #ifdef CONFIG_SECURITY |
| 1515 | if (!fs_info->security_opts.num_mnt_opts) { |
| 1516 | /* first time security setup, copy sec_opts to fs_info */ |
| 1517 | memcpy(&fs_info->security_opts, sec_opts, sizeof(*sec_opts)); |
| 1518 | } else { |
| 1519 | /* |
| 1520 | * Since SELinux (the only one supporting security_mnt_opts) |
| 1521 | * does NOT support changing context during remount/mount of |
| 1522 | * the same sb, this must be the same or part of the same |
| 1523 | * security options, just free it. |
| 1524 | */ |
| 1525 | security_free_mnt_opts(sec_opts); |
| 1526 | } |
| 1527 | #endif |
| 1528 | return ret; |
| 1529 | } |
| 1530 | |
| 1531 | /* |
| 1532 | * Find a superblock for the given device / mount point. |
| 1533 | * |
| 1534 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions |
| 1535 | * for multiple device setup. Make sure to keep it in sync. |
| 1536 | */ |
| 1537 | static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, |
| 1538 | const char *device_name, void *data) |
| 1539 | { |
| 1540 | struct block_device *bdev = NULL; |
| 1541 | struct super_block *s; |
| 1542 | struct btrfs_fs_devices *fs_devices = NULL; |
| 1543 | struct btrfs_fs_info *fs_info = NULL; |
| 1544 | struct security_mnt_opts new_sec_opts; |
| 1545 | fmode_t mode = FMODE_READ; |
| 1546 | char *subvol_name = NULL; |
| 1547 | u64 subvol_objectid = 0; |
| 1548 | int error = 0; |
| 1549 | |
| 1550 | if (!(flags & MS_RDONLY)) |
| 1551 | mode |= FMODE_WRITE; |
| 1552 | |
| 1553 | error = btrfs_parse_early_options(data, mode, fs_type, |
| 1554 | &subvol_name, &subvol_objectid, |
| 1555 | &fs_devices); |
| 1556 | if (error) { |
| 1557 | kfree(subvol_name); |
| 1558 | return ERR_PTR(error); |
| 1559 | } |
| 1560 | |
| 1561 | if (subvol_name || subvol_objectid != BTRFS_FS_TREE_OBJECTID) { |
| 1562 | /* mount_subvol() will free subvol_name. */ |
| 1563 | return mount_subvol(subvol_name, subvol_objectid, flags, |
| 1564 | device_name, data); |
| 1565 | } |
| 1566 | |
| 1567 | security_init_mnt_opts(&new_sec_opts); |
| 1568 | if (data) { |
| 1569 | error = parse_security_options(data, &new_sec_opts); |
| 1570 | if (error) |
| 1571 | return ERR_PTR(error); |
| 1572 | } |
| 1573 | |
| 1574 | error = btrfs_scan_one_device(device_name, mode, fs_type, &fs_devices); |
| 1575 | if (error) |
| 1576 | goto error_sec_opts; |
| 1577 | |
| 1578 | /* |
| 1579 | * Setup a dummy root and fs_info for test/set super. This is because |
| 1580 | * we don't actually fill this stuff out until open_ctree, but we need |
| 1581 | * it for searching for existing supers, so this lets us do that and |
| 1582 | * then open_ctree will properly initialize everything later. |
| 1583 | */ |
| 1584 | fs_info = kzalloc(sizeof(struct btrfs_fs_info), GFP_KERNEL); |
| 1585 | if (!fs_info) { |
| 1586 | error = -ENOMEM; |
| 1587 | goto error_sec_opts; |
| 1588 | } |
| 1589 | |
| 1590 | fs_info->fs_devices = fs_devices; |
| 1591 | |
| 1592 | fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); |
| 1593 | fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); |
| 1594 | security_init_mnt_opts(&fs_info->security_opts); |
| 1595 | if (!fs_info->super_copy || !fs_info->super_for_commit) { |
| 1596 | error = -ENOMEM; |
| 1597 | goto error_fs_info; |
| 1598 | } |
| 1599 | |
| 1600 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
| 1601 | if (error) |
| 1602 | goto error_fs_info; |
| 1603 | |
| 1604 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
| 1605 | error = -EACCES; |
| 1606 | goto error_close_devices; |
| 1607 | } |
| 1608 | |
| 1609 | bdev = fs_devices->latest_bdev; |
| 1610 | s = sget(fs_type, btrfs_test_super, btrfs_set_super, flags | MS_NOSEC, |
| 1611 | fs_info); |
| 1612 | if (IS_ERR(s)) { |
| 1613 | error = PTR_ERR(s); |
| 1614 | goto error_close_devices; |
| 1615 | } |
| 1616 | |
| 1617 | if (s->s_root) { |
| 1618 | btrfs_close_devices(fs_devices); |
| 1619 | free_fs_info(fs_info); |
| 1620 | if ((flags ^ s->s_flags) & MS_RDONLY) |
| 1621 | error = -EBUSY; |
| 1622 | } else { |
| 1623 | snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev); |
| 1624 | btrfs_sb(s)->bdev_holder = fs_type; |
| 1625 | error = btrfs_fill_super(s, fs_devices, data); |
| 1626 | } |
| 1627 | if (error) { |
| 1628 | deactivate_locked_super(s); |
| 1629 | goto error_sec_opts; |
| 1630 | } |
| 1631 | |
| 1632 | fs_info = btrfs_sb(s); |
| 1633 | error = setup_security_options(fs_info, s, &new_sec_opts); |
| 1634 | if (error) { |
| 1635 | deactivate_locked_super(s); |
| 1636 | goto error_sec_opts; |
| 1637 | } |
| 1638 | |
| 1639 | return dget(s->s_root); |
| 1640 | |
| 1641 | error_close_devices: |
| 1642 | btrfs_close_devices(fs_devices); |
| 1643 | error_fs_info: |
| 1644 | free_fs_info(fs_info); |
| 1645 | error_sec_opts: |
| 1646 | security_free_mnt_opts(&new_sec_opts); |
| 1647 | return ERR_PTR(error); |
| 1648 | } |
| 1649 | |
| 1650 | static void btrfs_resize_thread_pool(struct btrfs_fs_info *fs_info, |
| 1651 | int new_pool_size, int old_pool_size) |
| 1652 | { |
| 1653 | if (new_pool_size == old_pool_size) |
| 1654 | return; |
| 1655 | |
| 1656 | fs_info->thread_pool_size = new_pool_size; |
| 1657 | |
| 1658 | btrfs_info(fs_info, "resize thread pool %d -> %d", |
| 1659 | old_pool_size, new_pool_size); |
| 1660 | |
| 1661 | btrfs_workqueue_set_max(fs_info->workers, new_pool_size); |
| 1662 | btrfs_workqueue_set_max(fs_info->delalloc_workers, new_pool_size); |
| 1663 | btrfs_workqueue_set_max(fs_info->submit_workers, new_pool_size); |
| 1664 | btrfs_workqueue_set_max(fs_info->caching_workers, new_pool_size); |
| 1665 | btrfs_workqueue_set_max(fs_info->endio_workers, new_pool_size); |
| 1666 | btrfs_workqueue_set_max(fs_info->endio_meta_workers, new_pool_size); |
| 1667 | btrfs_workqueue_set_max(fs_info->endio_meta_write_workers, |
| 1668 | new_pool_size); |
| 1669 | btrfs_workqueue_set_max(fs_info->endio_write_workers, new_pool_size); |
| 1670 | btrfs_workqueue_set_max(fs_info->endio_freespace_worker, new_pool_size); |
| 1671 | btrfs_workqueue_set_max(fs_info->delayed_workers, new_pool_size); |
| 1672 | btrfs_workqueue_set_max(fs_info->readahead_workers, new_pool_size); |
| 1673 | btrfs_workqueue_set_max(fs_info->scrub_wr_completion_workers, |
| 1674 | new_pool_size); |
| 1675 | } |
| 1676 | |
| 1677 | static inline void btrfs_remount_prepare(struct btrfs_fs_info *fs_info) |
| 1678 | { |
| 1679 | set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); |
| 1680 | } |
| 1681 | |
| 1682 | static inline void btrfs_remount_begin(struct btrfs_fs_info *fs_info, |
| 1683 | unsigned long old_opts, int flags) |
| 1684 | { |
| 1685 | if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && |
| 1686 | (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || |
| 1687 | (flags & MS_RDONLY))) { |
| 1688 | /* wait for any defraggers to finish */ |
| 1689 | wait_event(fs_info->transaction_wait, |
| 1690 | (atomic_read(&fs_info->defrag_running) == 0)); |
| 1691 | if (flags & MS_RDONLY) |
| 1692 | sync_filesystem(fs_info->sb); |
| 1693 | } |
| 1694 | } |
| 1695 | |
| 1696 | static inline void btrfs_remount_cleanup(struct btrfs_fs_info *fs_info, |
| 1697 | unsigned long old_opts) |
| 1698 | { |
| 1699 | /* |
| 1700 | * We need to cleanup all defragable inodes if the autodefragment is |
| 1701 | * close or the filesystem is read only. |
| 1702 | */ |
| 1703 | if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && |
| 1704 | (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || sb_rdonly(fs_info->sb))) { |
| 1705 | btrfs_cleanup_defrag_inodes(fs_info); |
| 1706 | } |
| 1707 | |
| 1708 | clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); |
| 1709 | } |
| 1710 | |
| 1711 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
| 1712 | { |
| 1713 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| 1714 | struct btrfs_root *root = fs_info->tree_root; |
| 1715 | unsigned old_flags = sb->s_flags; |
| 1716 | unsigned long old_opts = fs_info->mount_opt; |
| 1717 | unsigned long old_compress_type = fs_info->compress_type; |
| 1718 | u64 old_max_inline = fs_info->max_inline; |
| 1719 | int old_thread_pool_size = fs_info->thread_pool_size; |
| 1720 | unsigned int old_metadata_ratio = fs_info->metadata_ratio; |
| 1721 | int ret; |
| 1722 | |
| 1723 | sync_filesystem(sb); |
| 1724 | btrfs_remount_prepare(fs_info); |
| 1725 | |
| 1726 | if (data) { |
| 1727 | struct security_mnt_opts new_sec_opts; |
| 1728 | |
| 1729 | security_init_mnt_opts(&new_sec_opts); |
| 1730 | ret = parse_security_options(data, &new_sec_opts); |
| 1731 | if (ret) |
| 1732 | goto restore; |
| 1733 | ret = setup_security_options(fs_info, sb, |
| 1734 | &new_sec_opts); |
| 1735 | if (ret) { |
| 1736 | security_free_mnt_opts(&new_sec_opts); |
| 1737 | goto restore; |
| 1738 | } |
| 1739 | } |
| 1740 | |
| 1741 | ret = btrfs_parse_options(fs_info, data, *flags); |
| 1742 | if (ret) { |
| 1743 | ret = -EINVAL; |
| 1744 | goto restore; |
| 1745 | } |
| 1746 | |
| 1747 | btrfs_remount_begin(fs_info, old_opts, *flags); |
| 1748 | btrfs_resize_thread_pool(fs_info, |
| 1749 | fs_info->thread_pool_size, old_thread_pool_size); |
| 1750 | |
| 1751 | if ((bool)(*flags & MS_RDONLY) == sb_rdonly(sb)) |
| 1752 | goto out; |
| 1753 | |
| 1754 | if (*flags & MS_RDONLY) { |
| 1755 | /* |
| 1756 | * this also happens on 'umount -rf' or on shutdown, when |
| 1757 | * the filesystem is busy. |
| 1758 | */ |
| 1759 | cancel_work_sync(&fs_info->async_reclaim_work); |
| 1760 | |
| 1761 | /* wait for the uuid_scan task to finish */ |
| 1762 | down(&fs_info->uuid_tree_rescan_sem); |
| 1763 | /* avoid complains from lockdep et al. */ |
| 1764 | up(&fs_info->uuid_tree_rescan_sem); |
| 1765 | |
| 1766 | sb->s_flags |= MS_RDONLY; |
| 1767 | |
| 1768 | /* |
| 1769 | * Setting MS_RDONLY will put the cleaner thread to |
| 1770 | * sleep at the next loop if it's already active. |
| 1771 | * If it's already asleep, we'll leave unused block |
| 1772 | * groups on disk until we're mounted read-write again |
| 1773 | * unless we clean them up here. |
| 1774 | */ |
| 1775 | btrfs_delete_unused_bgs(fs_info); |
| 1776 | |
| 1777 | btrfs_dev_replace_suspend_for_unmount(fs_info); |
| 1778 | btrfs_scrub_cancel(fs_info); |
| 1779 | btrfs_pause_balance(fs_info); |
| 1780 | |
| 1781 | ret = btrfs_commit_super(fs_info); |
| 1782 | if (ret) |
| 1783 | goto restore; |
| 1784 | } else { |
| 1785 | if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) { |
| 1786 | btrfs_err(fs_info, |
| 1787 | "Remounting read-write after error is not allowed"); |
| 1788 | ret = -EINVAL; |
| 1789 | goto restore; |
| 1790 | } |
| 1791 | if (fs_info->fs_devices->rw_devices == 0) { |
| 1792 | ret = -EACCES; |
| 1793 | goto restore; |
| 1794 | } |
| 1795 | |
| 1796 | if (!btrfs_check_rw_degradable(fs_info)) { |
| 1797 | btrfs_warn(fs_info, |
| 1798 | "too many missing devices, writeable remount is not allowed"); |
| 1799 | ret = -EACCES; |
| 1800 | goto restore; |
| 1801 | } |
| 1802 | |
| 1803 | if (btrfs_super_log_root(fs_info->super_copy) != 0) { |
| 1804 | ret = -EINVAL; |
| 1805 | goto restore; |
| 1806 | } |
| 1807 | |
| 1808 | ret = btrfs_cleanup_fs_roots(fs_info); |
| 1809 | if (ret) |
| 1810 | goto restore; |
| 1811 | |
| 1812 | /* recover relocation */ |
| 1813 | mutex_lock(&fs_info->cleaner_mutex); |
| 1814 | ret = btrfs_recover_relocation(root); |
| 1815 | mutex_unlock(&fs_info->cleaner_mutex); |
| 1816 | if (ret) |
| 1817 | goto restore; |
| 1818 | |
| 1819 | ret = btrfs_resume_balance_async(fs_info); |
| 1820 | if (ret) |
| 1821 | goto restore; |
| 1822 | |
| 1823 | ret = btrfs_resume_dev_replace_async(fs_info); |
| 1824 | if (ret) { |
| 1825 | btrfs_warn(fs_info, "failed to resume dev_replace"); |
| 1826 | goto restore; |
| 1827 | } |
| 1828 | |
| 1829 | btrfs_qgroup_rescan_resume(fs_info); |
| 1830 | |
| 1831 | if (!fs_info->uuid_root) { |
| 1832 | btrfs_info(fs_info, "creating UUID tree"); |
| 1833 | ret = btrfs_create_uuid_tree(fs_info); |
| 1834 | if (ret) { |
| 1835 | btrfs_warn(fs_info, |
| 1836 | "failed to create the UUID tree %d", |
| 1837 | ret); |
| 1838 | goto restore; |
| 1839 | } |
| 1840 | } |
| 1841 | sb->s_flags &= ~MS_RDONLY; |
| 1842 | |
| 1843 | set_bit(BTRFS_FS_OPEN, &fs_info->flags); |
| 1844 | } |
| 1845 | out: |
| 1846 | wake_up_process(fs_info->transaction_kthread); |
| 1847 | btrfs_remount_cleanup(fs_info, old_opts); |
| 1848 | return 0; |
| 1849 | |
| 1850 | restore: |
| 1851 | /* We've hit an error - don't reset MS_RDONLY */ |
| 1852 | if (sb_rdonly(sb)) |
| 1853 | old_flags |= MS_RDONLY; |
| 1854 | sb->s_flags = old_flags; |
| 1855 | fs_info->mount_opt = old_opts; |
| 1856 | fs_info->compress_type = old_compress_type; |
| 1857 | fs_info->max_inline = old_max_inline; |
| 1858 | btrfs_resize_thread_pool(fs_info, |
| 1859 | old_thread_pool_size, fs_info->thread_pool_size); |
| 1860 | fs_info->metadata_ratio = old_metadata_ratio; |
| 1861 | btrfs_remount_cleanup(fs_info, old_opts); |
| 1862 | return ret; |
| 1863 | } |
| 1864 | |
| 1865 | /* Used to sort the devices by max_avail(descending sort) */ |
| 1866 | static int btrfs_cmp_device_free_bytes(const void *dev_info1, |
| 1867 | const void *dev_info2) |
| 1868 | { |
| 1869 | if (((struct btrfs_device_info *)dev_info1)->max_avail > |
| 1870 | ((struct btrfs_device_info *)dev_info2)->max_avail) |
| 1871 | return -1; |
| 1872 | else if (((struct btrfs_device_info *)dev_info1)->max_avail < |
| 1873 | ((struct btrfs_device_info *)dev_info2)->max_avail) |
| 1874 | return 1; |
| 1875 | else |
| 1876 | return 0; |
| 1877 | } |
| 1878 | |
| 1879 | /* |
| 1880 | * sort the devices by max_avail, in which max free extent size of each device |
| 1881 | * is stored.(Descending Sort) |
| 1882 | */ |
| 1883 | static inline void btrfs_descending_sort_devices( |
| 1884 | struct btrfs_device_info *devices, |
| 1885 | size_t nr_devices) |
| 1886 | { |
| 1887 | sort(devices, nr_devices, sizeof(struct btrfs_device_info), |
| 1888 | btrfs_cmp_device_free_bytes, NULL); |
| 1889 | } |
| 1890 | |
| 1891 | /* |
| 1892 | * The helper to calc the free space on the devices that can be used to store |
| 1893 | * file data. |
| 1894 | */ |
| 1895 | static int btrfs_calc_avail_data_space(struct btrfs_fs_info *fs_info, |
| 1896 | u64 *free_bytes) |
| 1897 | { |
| 1898 | struct btrfs_device_info *devices_info; |
| 1899 | struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; |
| 1900 | struct btrfs_device *device; |
| 1901 | u64 skip_space; |
| 1902 | u64 type; |
| 1903 | u64 avail_space; |
| 1904 | u64 min_stripe_size; |
| 1905 | int min_stripes = 1, num_stripes = 1; |
| 1906 | int i = 0, nr_devices; |
| 1907 | |
| 1908 | /* |
| 1909 | * We aren't under the device list lock, so this is racy-ish, but good |
| 1910 | * enough for our purposes. |
| 1911 | */ |
| 1912 | nr_devices = fs_info->fs_devices->open_devices; |
| 1913 | if (!nr_devices) { |
| 1914 | smp_mb(); |
| 1915 | nr_devices = fs_info->fs_devices->open_devices; |
| 1916 | ASSERT(nr_devices); |
| 1917 | if (!nr_devices) { |
| 1918 | *free_bytes = 0; |
| 1919 | return 0; |
| 1920 | } |
| 1921 | } |
| 1922 | |
| 1923 | devices_info = kmalloc_array(nr_devices, sizeof(*devices_info), |
| 1924 | GFP_KERNEL); |
| 1925 | if (!devices_info) |
| 1926 | return -ENOMEM; |
| 1927 | |
| 1928 | /* calc min stripe number for data space allocation */ |
| 1929 | type = btrfs_data_alloc_profile(fs_info); |
| 1930 | if (type & BTRFS_BLOCK_GROUP_RAID0) { |
| 1931 | min_stripes = 2; |
| 1932 | num_stripes = nr_devices; |
| 1933 | } else if (type & BTRFS_BLOCK_GROUP_RAID1) { |
| 1934 | min_stripes = 2; |
| 1935 | num_stripes = 2; |
| 1936 | } else if (type & BTRFS_BLOCK_GROUP_RAID10) { |
| 1937 | min_stripes = 4; |
| 1938 | num_stripes = 4; |
| 1939 | } |
| 1940 | |
| 1941 | if (type & BTRFS_BLOCK_GROUP_DUP) |
| 1942 | min_stripe_size = 2 * BTRFS_STRIPE_LEN; |
| 1943 | else |
| 1944 | min_stripe_size = BTRFS_STRIPE_LEN; |
| 1945 | |
| 1946 | rcu_read_lock(); |
| 1947 | list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) { |
| 1948 | if (!device->in_fs_metadata || !device->bdev || |
| 1949 | device->is_tgtdev_for_dev_replace) |
| 1950 | continue; |
| 1951 | |
| 1952 | if (i >= nr_devices) |
| 1953 | break; |
| 1954 | |
| 1955 | avail_space = device->total_bytes - device->bytes_used; |
| 1956 | |
| 1957 | /* align with stripe_len */ |
| 1958 | avail_space = div_u64(avail_space, BTRFS_STRIPE_LEN); |
| 1959 | avail_space *= BTRFS_STRIPE_LEN; |
| 1960 | |
| 1961 | /* |
| 1962 | * In order to avoid overwriting the superblock on the drive, |
| 1963 | * btrfs starts at an offset of at least 1MB when doing chunk |
| 1964 | * allocation. |
| 1965 | */ |
| 1966 | skip_space = SZ_1M; |
| 1967 | |
| 1968 | /* |
| 1969 | * we can use the free space in [0, skip_space - 1], subtract |
| 1970 | * it from the total. |
| 1971 | */ |
| 1972 | if (avail_space && avail_space >= skip_space) |
| 1973 | avail_space -= skip_space; |
| 1974 | else |
| 1975 | avail_space = 0; |
| 1976 | |
| 1977 | if (avail_space < min_stripe_size) |
| 1978 | continue; |
| 1979 | |
| 1980 | devices_info[i].dev = device; |
| 1981 | devices_info[i].max_avail = avail_space; |
| 1982 | |
| 1983 | i++; |
| 1984 | } |
| 1985 | rcu_read_unlock(); |
| 1986 | |
| 1987 | nr_devices = i; |
| 1988 | |
| 1989 | btrfs_descending_sort_devices(devices_info, nr_devices); |
| 1990 | |
| 1991 | i = nr_devices - 1; |
| 1992 | avail_space = 0; |
| 1993 | while (nr_devices >= min_stripes) { |
| 1994 | if (num_stripes > nr_devices) |
| 1995 | num_stripes = nr_devices; |
| 1996 | |
| 1997 | if (devices_info[i].max_avail >= min_stripe_size) { |
| 1998 | int j; |
| 1999 | u64 alloc_size; |
| 2000 | |
| 2001 | avail_space += devices_info[i].max_avail * num_stripes; |
| 2002 | alloc_size = devices_info[i].max_avail; |
| 2003 | for (j = i + 1 - num_stripes; j <= i; j++) |
| 2004 | devices_info[j].max_avail -= alloc_size; |
| 2005 | } |
| 2006 | i--; |
| 2007 | nr_devices--; |
| 2008 | } |
| 2009 | |
| 2010 | kfree(devices_info); |
| 2011 | *free_bytes = avail_space; |
| 2012 | return 0; |
| 2013 | } |
| 2014 | |
| 2015 | /* |
| 2016 | * Calculate numbers for 'df', pessimistic in case of mixed raid profiles. |
| 2017 | * |
| 2018 | * If there's a redundant raid level at DATA block groups, use the respective |
| 2019 | * multiplier to scale the sizes. |
| 2020 | * |
| 2021 | * Unused device space usage is based on simulating the chunk allocator |
| 2022 | * algorithm that respects the device sizes and order of allocations. This is |
| 2023 | * a close approximation of the actual use but there are other factors that may |
| 2024 | * change the result (like a new metadata chunk). |
| 2025 | * |
| 2026 | * If metadata is exhausted, f_bavail will be 0. |
| 2027 | */ |
| 2028 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
| 2029 | { |
| 2030 | struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb); |
| 2031 | struct btrfs_super_block *disk_super = fs_info->super_copy; |
| 2032 | struct list_head *head = &fs_info->space_info; |
| 2033 | struct btrfs_space_info *found; |
| 2034 | u64 total_used = 0; |
| 2035 | u64 total_free_data = 0; |
| 2036 | u64 total_free_meta = 0; |
| 2037 | int bits = dentry->d_sb->s_blocksize_bits; |
| 2038 | __be32 *fsid = (__be32 *)fs_info->fsid; |
| 2039 | unsigned factor = 1; |
| 2040 | struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; |
| 2041 | int ret; |
| 2042 | u64 thresh = 0; |
| 2043 | int mixed = 0; |
| 2044 | |
| 2045 | rcu_read_lock(); |
| 2046 | list_for_each_entry_rcu(found, head, list) { |
| 2047 | if (found->flags & BTRFS_BLOCK_GROUP_DATA) { |
| 2048 | int i; |
| 2049 | |
| 2050 | total_free_data += found->disk_total - found->disk_used; |
| 2051 | total_free_data -= |
| 2052 | btrfs_account_ro_block_groups_free_space(found); |
| 2053 | |
| 2054 | for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { |
| 2055 | if (!list_empty(&found->block_groups[i])) { |
| 2056 | switch (i) { |
| 2057 | case BTRFS_RAID_DUP: |
| 2058 | case BTRFS_RAID_RAID1: |
| 2059 | case BTRFS_RAID_RAID10: |
| 2060 | factor = 2; |
| 2061 | } |
| 2062 | } |
| 2063 | } |
| 2064 | } |
| 2065 | |
| 2066 | /* |
| 2067 | * Metadata in mixed block goup profiles are accounted in data |
| 2068 | */ |
| 2069 | if (!mixed && found->flags & BTRFS_BLOCK_GROUP_METADATA) { |
| 2070 | if (found->flags & BTRFS_BLOCK_GROUP_DATA) |
| 2071 | mixed = 1; |
| 2072 | else |
| 2073 | total_free_meta += found->disk_total - |
| 2074 | found->disk_used; |
| 2075 | } |
| 2076 | |
| 2077 | total_used += found->disk_used; |
| 2078 | } |
| 2079 | |
| 2080 | rcu_read_unlock(); |
| 2081 | |
| 2082 | buf->f_blocks = div_u64(btrfs_super_total_bytes(disk_super), factor); |
| 2083 | buf->f_blocks >>= bits; |
| 2084 | buf->f_bfree = buf->f_blocks - (div_u64(total_used, factor) >> bits); |
| 2085 | |
| 2086 | /* Account global block reserve as used, it's in logical size already */ |
| 2087 | spin_lock(&block_rsv->lock); |
| 2088 | /* Mixed block groups accounting is not byte-accurate, avoid overflow */ |
| 2089 | if (buf->f_bfree >= block_rsv->size >> bits) |
| 2090 | buf->f_bfree -= block_rsv->size >> bits; |
| 2091 | else |
| 2092 | buf->f_bfree = 0; |
| 2093 | spin_unlock(&block_rsv->lock); |
| 2094 | |
| 2095 | buf->f_bavail = div_u64(total_free_data, factor); |
| 2096 | ret = btrfs_calc_avail_data_space(fs_info, &total_free_data); |
| 2097 | if (ret) |
| 2098 | return ret; |
| 2099 | buf->f_bavail += div_u64(total_free_data, factor); |
| 2100 | buf->f_bavail = buf->f_bavail >> bits; |
| 2101 | |
| 2102 | /* |
| 2103 | * We calculate the remaining metadata space minus global reserve. If |
| 2104 | * this is (supposedly) smaller than zero, there's no space. But this |
| 2105 | * does not hold in practice, the exhausted state happens where's still |
| 2106 | * some positive delta. So we apply some guesswork and compare the |
| 2107 | * delta to a 4M threshold. (Practically observed delta was ~2M.) |
| 2108 | * |
| 2109 | * We probably cannot calculate the exact threshold value because this |
| 2110 | * depends on the internal reservations requested by various |
| 2111 | * operations, so some operations that consume a few metadata will |
| 2112 | * succeed even if the Avail is zero. But this is better than the other |
| 2113 | * way around. |
| 2114 | */ |
| 2115 | thresh = 4 * 1024 * 1024; |
| 2116 | |
| 2117 | if (!mixed && total_free_meta - thresh < block_rsv->size) |
| 2118 | buf->f_bavail = 0; |
| 2119 | |
| 2120 | buf->f_type = BTRFS_SUPER_MAGIC; |
| 2121 | buf->f_bsize = dentry->d_sb->s_blocksize; |
| 2122 | buf->f_namelen = BTRFS_NAME_LEN; |
| 2123 | |
| 2124 | /* We treat it as constant endianness (it doesn't matter _which_) |
| 2125 | because we want the fsid to come out the same whether mounted |
| 2126 | on a big-endian or little-endian host */ |
| 2127 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); |
| 2128 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); |
| 2129 | /* Mask in the root object ID too, to disambiguate subvols */ |
| 2130 | buf->f_fsid.val[0] ^= BTRFS_I(d_inode(dentry))->root->objectid >> 32; |
| 2131 | buf->f_fsid.val[1] ^= BTRFS_I(d_inode(dentry))->root->objectid; |
| 2132 | |
| 2133 | return 0; |
| 2134 | } |
| 2135 | |
| 2136 | static void btrfs_kill_super(struct super_block *sb) |
| 2137 | { |
| 2138 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| 2139 | kill_anon_super(sb); |
| 2140 | free_fs_info(fs_info); |
| 2141 | } |
| 2142 | |
| 2143 | static struct file_system_type btrfs_fs_type = { |
| 2144 | .owner = THIS_MODULE, |
| 2145 | .name = "btrfs", |
| 2146 | .mount = btrfs_mount, |
| 2147 | .kill_sb = btrfs_kill_super, |
| 2148 | .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA, |
| 2149 | }; |
| 2150 | MODULE_ALIAS_FS("btrfs"); |
| 2151 | |
| 2152 | static int btrfs_control_open(struct inode *inode, struct file *file) |
| 2153 | { |
| 2154 | /* |
| 2155 | * The control file's private_data is used to hold the |
| 2156 | * transaction when it is started and is used to keep |
| 2157 | * track of whether a transaction is already in progress. |
| 2158 | */ |
| 2159 | file->private_data = NULL; |
| 2160 | return 0; |
| 2161 | } |
| 2162 | |
| 2163 | /* |
| 2164 | * used by btrfsctl to scan devices when no FS is mounted |
| 2165 | */ |
| 2166 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
| 2167 | unsigned long arg) |
| 2168 | { |
| 2169 | struct btrfs_ioctl_vol_args *vol; |
| 2170 | struct btrfs_fs_devices *fs_devices; |
| 2171 | int ret = -ENOTTY; |
| 2172 | |
| 2173 | if (!capable(CAP_SYS_ADMIN)) |
| 2174 | return -EPERM; |
| 2175 | |
| 2176 | vol = memdup_user((void __user *)arg, sizeof(*vol)); |
| 2177 | if (IS_ERR(vol)) |
| 2178 | return PTR_ERR(vol); |
| 2179 | |
| 2180 | switch (cmd) { |
| 2181 | case BTRFS_IOC_SCAN_DEV: |
| 2182 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
| 2183 | &btrfs_fs_type, &fs_devices); |
| 2184 | break; |
| 2185 | case BTRFS_IOC_DEVICES_READY: |
| 2186 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
| 2187 | &btrfs_fs_type, &fs_devices); |
| 2188 | if (ret) |
| 2189 | break; |
| 2190 | ret = !(fs_devices->num_devices == fs_devices->total_devices); |
| 2191 | break; |
| 2192 | case BTRFS_IOC_GET_SUPPORTED_FEATURES: |
| 2193 | ret = btrfs_ioctl_get_supported_features((void __user*)arg); |
| 2194 | break; |
| 2195 | } |
| 2196 | |
| 2197 | kfree(vol); |
| 2198 | return ret; |
| 2199 | } |
| 2200 | |
| 2201 | static int btrfs_freeze(struct super_block *sb) |
| 2202 | { |
| 2203 | struct btrfs_trans_handle *trans; |
| 2204 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| 2205 | struct btrfs_root *root = fs_info->tree_root; |
| 2206 | |
| 2207 | set_bit(BTRFS_FS_FROZEN, &fs_info->flags); |
| 2208 | /* |
| 2209 | * We don't need a barrier here, we'll wait for any transaction that |
| 2210 | * could be in progress on other threads (and do delayed iputs that |
| 2211 | * we want to avoid on a frozen filesystem), or do the commit |
| 2212 | * ourselves. |
| 2213 | */ |
| 2214 | trans = btrfs_attach_transaction_barrier(root); |
| 2215 | if (IS_ERR(trans)) { |
| 2216 | /* no transaction, don't bother */ |
| 2217 | if (PTR_ERR(trans) == -ENOENT) |
| 2218 | return 0; |
| 2219 | return PTR_ERR(trans); |
| 2220 | } |
| 2221 | return btrfs_commit_transaction(trans); |
| 2222 | } |
| 2223 | |
| 2224 | static int btrfs_unfreeze(struct super_block *sb) |
| 2225 | { |
| 2226 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| 2227 | |
| 2228 | clear_bit(BTRFS_FS_FROZEN, &fs_info->flags); |
| 2229 | return 0; |
| 2230 | } |
| 2231 | |
| 2232 | static int btrfs_show_devname(struct seq_file *m, struct dentry *root) |
| 2233 | { |
| 2234 | struct btrfs_fs_info *fs_info = btrfs_sb(root->d_sb); |
| 2235 | struct btrfs_fs_devices *cur_devices; |
| 2236 | struct btrfs_device *dev, *first_dev = NULL; |
| 2237 | struct list_head *head; |
| 2238 | struct rcu_string *name; |
| 2239 | |
| 2240 | mutex_lock(&fs_info->fs_devices->device_list_mutex); |
| 2241 | cur_devices = fs_info->fs_devices; |
| 2242 | while (cur_devices) { |
| 2243 | head = &cur_devices->devices; |
| 2244 | list_for_each_entry(dev, head, dev_list) { |
| 2245 | if (dev->missing) |
| 2246 | continue; |
| 2247 | if (!dev->name) |
| 2248 | continue; |
| 2249 | if (!first_dev || dev->devid < first_dev->devid) |
| 2250 | first_dev = dev; |
| 2251 | } |
| 2252 | cur_devices = cur_devices->seed; |
| 2253 | } |
| 2254 | |
| 2255 | if (first_dev) { |
| 2256 | rcu_read_lock(); |
| 2257 | name = rcu_dereference(first_dev->name); |
| 2258 | seq_escape(m, name->str, " \t\n\\"); |
| 2259 | rcu_read_unlock(); |
| 2260 | } else { |
| 2261 | WARN_ON(1); |
| 2262 | } |
| 2263 | mutex_unlock(&fs_info->fs_devices->device_list_mutex); |
| 2264 | return 0; |
| 2265 | } |
| 2266 | |
| 2267 | static const struct super_operations btrfs_super_ops = { |
| 2268 | .drop_inode = btrfs_drop_inode, |
| 2269 | .evict_inode = btrfs_evict_inode, |
| 2270 | .put_super = btrfs_put_super, |
| 2271 | .sync_fs = btrfs_sync_fs, |
| 2272 | .show_options = btrfs_show_options, |
| 2273 | .show_devname = btrfs_show_devname, |
| 2274 | .write_inode = btrfs_write_inode, |
| 2275 | .alloc_inode = btrfs_alloc_inode, |
| 2276 | .destroy_inode = btrfs_destroy_inode, |
| 2277 | .statfs = btrfs_statfs, |
| 2278 | .remount_fs = btrfs_remount, |
| 2279 | .freeze_fs = btrfs_freeze, |
| 2280 | .unfreeze_fs = btrfs_unfreeze, |
| 2281 | }; |
| 2282 | |
| 2283 | static const struct file_operations btrfs_ctl_fops = { |
| 2284 | .open = btrfs_control_open, |
| 2285 | .unlocked_ioctl = btrfs_control_ioctl, |
| 2286 | .compat_ioctl = btrfs_control_ioctl, |
| 2287 | .owner = THIS_MODULE, |
| 2288 | .llseek = noop_llseek, |
| 2289 | }; |
| 2290 | |
| 2291 | static struct miscdevice btrfs_misc = { |
| 2292 | .minor = BTRFS_MINOR, |
| 2293 | .name = "btrfs-control", |
| 2294 | .fops = &btrfs_ctl_fops |
| 2295 | }; |
| 2296 | |
| 2297 | MODULE_ALIAS_MISCDEV(BTRFS_MINOR); |
| 2298 | MODULE_ALIAS("devname:btrfs-control"); |
| 2299 | |
| 2300 | static int btrfs_interface_init(void) |
| 2301 | { |
| 2302 | return misc_register(&btrfs_misc); |
| 2303 | } |
| 2304 | |
| 2305 | static void btrfs_interface_exit(void) |
| 2306 | { |
| 2307 | misc_deregister(&btrfs_misc); |
| 2308 | } |
| 2309 | |
| 2310 | static void btrfs_print_mod_info(void) |
| 2311 | { |
| 2312 | pr_info("Btrfs loaded, crc32c=%s" |
| 2313 | #ifdef CONFIG_BTRFS_DEBUG |
| 2314 | ", debug=on" |
| 2315 | #endif |
| 2316 | #ifdef CONFIG_BTRFS_ASSERT |
| 2317 | ", assert=on" |
| 2318 | #endif |
| 2319 | #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY |
| 2320 | ", integrity-checker=on" |
| 2321 | #endif |
| 2322 | "\n", |
| 2323 | btrfs_crc32c_impl()); |
| 2324 | } |
| 2325 | |
| 2326 | static int __init init_btrfs_fs(void) |
| 2327 | { |
| 2328 | int err; |
| 2329 | |
| 2330 | err = btrfs_hash_init(); |
| 2331 | if (err) |
| 2332 | return err; |
| 2333 | |
| 2334 | btrfs_props_init(); |
| 2335 | |
| 2336 | err = btrfs_init_sysfs(); |
| 2337 | if (err) |
| 2338 | goto free_hash; |
| 2339 | |
| 2340 | btrfs_init_compress(); |
| 2341 | |
| 2342 | err = btrfs_init_cachep(); |
| 2343 | if (err) |
| 2344 | goto free_compress; |
| 2345 | |
| 2346 | err = extent_io_init(); |
| 2347 | if (err) |
| 2348 | goto free_cachep; |
| 2349 | |
| 2350 | err = extent_map_init(); |
| 2351 | if (err) |
| 2352 | goto free_extent_io; |
| 2353 | |
| 2354 | err = ordered_data_init(); |
| 2355 | if (err) |
| 2356 | goto free_extent_map; |
| 2357 | |
| 2358 | err = btrfs_delayed_inode_init(); |
| 2359 | if (err) |
| 2360 | goto free_ordered_data; |
| 2361 | |
| 2362 | err = btrfs_auto_defrag_init(); |
| 2363 | if (err) |
| 2364 | goto free_delayed_inode; |
| 2365 | |
| 2366 | err = btrfs_delayed_ref_init(); |
| 2367 | if (err) |
| 2368 | goto free_auto_defrag; |
| 2369 | |
| 2370 | err = btrfs_prelim_ref_init(); |
| 2371 | if (err) |
| 2372 | goto free_delayed_ref; |
| 2373 | |
| 2374 | err = btrfs_end_io_wq_init(); |
| 2375 | if (err) |
| 2376 | goto free_prelim_ref; |
| 2377 | |
| 2378 | err = btrfs_interface_init(); |
| 2379 | if (err) |
| 2380 | goto free_end_io_wq; |
| 2381 | |
| 2382 | btrfs_init_lockdep(); |
| 2383 | |
| 2384 | btrfs_print_mod_info(); |
| 2385 | |
| 2386 | err = btrfs_run_sanity_tests(); |
| 2387 | if (err) |
| 2388 | goto unregister_ioctl; |
| 2389 | |
| 2390 | err = register_filesystem(&btrfs_fs_type); |
| 2391 | if (err) |
| 2392 | goto unregister_ioctl; |
| 2393 | |
| 2394 | return 0; |
| 2395 | |
| 2396 | unregister_ioctl: |
| 2397 | btrfs_interface_exit(); |
| 2398 | free_end_io_wq: |
| 2399 | btrfs_end_io_wq_exit(); |
| 2400 | free_prelim_ref: |
| 2401 | btrfs_prelim_ref_exit(); |
| 2402 | free_delayed_ref: |
| 2403 | btrfs_delayed_ref_exit(); |
| 2404 | free_auto_defrag: |
| 2405 | btrfs_auto_defrag_exit(); |
| 2406 | free_delayed_inode: |
| 2407 | btrfs_delayed_inode_exit(); |
| 2408 | free_ordered_data: |
| 2409 | ordered_data_exit(); |
| 2410 | free_extent_map: |
| 2411 | extent_map_exit(); |
| 2412 | free_extent_io: |
| 2413 | extent_io_exit(); |
| 2414 | free_cachep: |
| 2415 | btrfs_destroy_cachep(); |
| 2416 | free_compress: |
| 2417 | btrfs_exit_compress(); |
| 2418 | btrfs_exit_sysfs(); |
| 2419 | free_hash: |
| 2420 | btrfs_hash_exit(); |
| 2421 | return err; |
| 2422 | } |
| 2423 | |
| 2424 | static void __exit exit_btrfs_fs(void) |
| 2425 | { |
| 2426 | btrfs_destroy_cachep(); |
| 2427 | btrfs_delayed_ref_exit(); |
| 2428 | btrfs_auto_defrag_exit(); |
| 2429 | btrfs_delayed_inode_exit(); |
| 2430 | btrfs_prelim_ref_exit(); |
| 2431 | ordered_data_exit(); |
| 2432 | extent_map_exit(); |
| 2433 | extent_io_exit(); |
| 2434 | btrfs_interface_exit(); |
| 2435 | btrfs_end_io_wq_exit(); |
| 2436 | unregister_filesystem(&btrfs_fs_type); |
| 2437 | btrfs_exit_sysfs(); |
| 2438 | btrfs_cleanup_fs_uuids(); |
| 2439 | btrfs_exit_compress(); |
| 2440 | btrfs_hash_exit(); |
| 2441 | } |
| 2442 | |
| 2443 | late_initcall(init_btrfs_fs); |
| 2444 | module_exit(exit_btrfs_fs) |
| 2445 | |
| 2446 | MODULE_LICENSE("GPL"); |