| /* |
| * Copyright (C) 2007 Oracle. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public |
| * License v2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public |
| * License along with this program; if not, write to the |
| * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| * Boston, MA 021110-1307, USA. |
| */ |
| |
| #include <linux/blkdev.h> |
| #include <linux/module.h> |
| #include <linux/buffer_head.h> |
| #include <linux/fs.h> |
| #include <linux/pagemap.h> |
| #include <linux/highmem.h> |
| #include <linux/time.h> |
| #include <linux/init.h> |
| #include <linux/seq_file.h> |
| #include <linux/string.h> |
| #include <linux/backing-dev.h> |
| #include <linux/mount.h> |
| #include <linux/mpage.h> |
| #include <linux/swap.h> |
| #include <linux/writeback.h> |
| #include <linux/statfs.h> |
| #include <linux/compat.h> |
| #include <linux/parser.h> |
| #include <linux/ctype.h> |
| #include <linux/namei.h> |
| #include <linux/miscdevice.h> |
| #include <linux/magic.h> |
| #include <linux/slab.h> |
| #include <linux/cleancache.h> |
| #include <linux/ratelimit.h> |
| #include <linux/btrfs.h> |
| #include "delayed-inode.h" |
| #include "ctree.h" |
| #include "disk-io.h" |
| #include "transaction.h" |
| #include "btrfs_inode.h" |
| #include "print-tree.h" |
| #include "hash.h" |
| #include "props.h" |
| #include "xattr.h" |
| #include "volumes.h" |
| #include "export.h" |
| #include "compression.h" |
| #include "rcu-string.h" |
| #include "dev-replace.h" |
| #include "free-space-cache.h" |
| #include "backref.h" |
| #include "tests/btrfs-tests.h" |
| |
| #include "qgroup.h" |
| #define CREATE_TRACE_POINTS |
| #include <trace/events/btrfs.h> |
| |
| static const struct super_operations btrfs_super_ops; |
| static struct file_system_type btrfs_fs_type; |
| |
| static int btrfs_remount(struct super_block *sb, int *flags, char *data); |
| |
| const char *btrfs_decode_error(int errno) |
| { |
| char *errstr = "unknown"; |
| |
| switch (errno) { |
| case -EIO: |
| errstr = "IO failure"; |
| break; |
| case -ENOMEM: |
| errstr = "Out of memory"; |
| break; |
| case -EROFS: |
| errstr = "Readonly filesystem"; |
| break; |
| case -EEXIST: |
| errstr = "Object already exists"; |
| break; |
| case -ENOSPC: |
| errstr = "No space left"; |
| break; |
| case -ENOENT: |
| errstr = "No such entry"; |
| break; |
| } |
| |
| return errstr; |
| } |
| |
| /* btrfs handle error by forcing the filesystem readonly */ |
| static void btrfs_handle_error(struct btrfs_fs_info *fs_info) |
| { |
| struct super_block *sb = fs_info->sb; |
| |
| if (sb->s_flags & MS_RDONLY) |
| return; |
| |
| if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) { |
| sb->s_flags |= MS_RDONLY; |
| btrfs_info(fs_info, "forced readonly"); |
| /* |
| * Note that a running device replace operation is not |
| * canceled here although there is no way to update |
| * the progress. It would add the risk of a deadlock, |
| * therefore the canceling is omitted. The only penalty |
| * is that some I/O remains active until the procedure |
| * completes. The next time when the filesystem is |
| * mounted writeable again, the device replace |
| * operation continues. |
| */ |
| } |
| } |
| |
| /* |
| * __btrfs_handle_fs_error decodes expected errors from the caller and |
| * invokes the approciate error response. |
| */ |
| __cold |
| void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function, |
| unsigned int line, int errno, const char *fmt, ...) |
| { |
| struct super_block *sb = fs_info->sb; |
| #ifdef CONFIG_PRINTK |
| const char *errstr; |
| #endif |
| |
| /* |
| * Special case: if the error is EROFS, and we're already |
| * under MS_RDONLY, then it is safe here. |
| */ |
| if (errno == -EROFS && (sb->s_flags & MS_RDONLY)) |
| return; |
| |
| #ifdef CONFIG_PRINTK |
| errstr = btrfs_decode_error(errno); |
| if (fmt) { |
| struct va_format vaf; |
| va_list args; |
| |
| va_start(args, fmt); |
| vaf.fmt = fmt; |
| vaf.va = &args; |
| |
| printk(KERN_CRIT |
| "BTRFS: error (device %s) in %s:%d: errno=%d %s (%pV)\n", |
| sb->s_id, function, line, errno, errstr, &vaf); |
| va_end(args); |
| } else { |
| printk(KERN_CRIT "BTRFS: error (device %s) in %s:%d: errno=%d %s\n", |
| sb->s_id, function, line, errno, errstr); |
| } |
| #endif |
| |
| /* |
| * Today we only save the error info to memory. Long term we'll |
| * also send it down to the disk |
| */ |
| set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state); |
| |
| /* Don't go through full error handling during mount */ |
| if (sb->s_flags & MS_BORN) |
| btrfs_handle_error(fs_info); |
| } |
| |
| #ifdef CONFIG_PRINTK |
| static const char * const logtypes[] = { |
| "emergency", |
| "alert", |
| "critical", |
| "error", |
| "warning", |
| "notice", |
| "info", |
| "debug", |
| }; |
| |
| void btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...) |
| { |
| struct super_block *sb = fs_info->sb; |
| char lvl[4]; |
| struct va_format vaf; |
| va_list args; |
| const char *type = logtypes[4]; |
| int kern_level; |
| |
| va_start(args, fmt); |
| |
| kern_level = printk_get_level(fmt); |
| if (kern_level) { |
| size_t size = printk_skip_level(fmt) - fmt; |
| memcpy(lvl, fmt, size); |
| lvl[size] = '\0'; |
| fmt += size; |
| type = logtypes[kern_level - '0']; |
| } else |
| *lvl = '\0'; |
| |
| vaf.fmt = fmt; |
| vaf.va = &args; |
| |
| printk("%sBTRFS %s (device %s): %pV\n", lvl, type, sb->s_id, &vaf); |
| |
| va_end(args); |
| } |
| #endif |
| |
| /* |
| * We only mark the transaction aborted and then set the file system read-only. |
| * This will prevent new transactions from starting or trying to join this |
| * one. |
| * |
| * This means that error recovery at the call site is limited to freeing |
| * any local memory allocations and passing the error code up without |
| * further cleanup. The transaction should complete as it normally would |
| * in the call path but will return -EIO. |
| * |
| * We'll complete the cleanup in btrfs_end_transaction and |
| * btrfs_commit_transaction. |
| */ |
| __cold |
| void __btrfs_abort_transaction(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, const char *function, |
| unsigned int line, int errno) |
| { |
| trans->aborted = errno; |
| /* Nothing used. The other threads that have joined this |
| * transaction may be able to continue. */ |
| if (!trans->dirty && list_empty(&trans->new_bgs)) { |
| const char *errstr; |
| |
| errstr = btrfs_decode_error(errno); |
| btrfs_warn(root->fs_info, |
| "%s:%d: Aborting unused transaction(%s).", |
| function, line, errstr); |
| return; |
| } |
| ACCESS_ONCE(trans->transaction->aborted) = errno; |
| /* Wake up anybody who may be waiting on this transaction */ |
| wake_up(&root->fs_info->transaction_wait); |
| wake_up(&root->fs_info->transaction_blocked_wait); |
| __btrfs_handle_fs_error(root->fs_info, function, line, errno, NULL); |
| } |
| /* |
| * __btrfs_panic decodes unexpected, fatal errors from the caller, |
| * issues an alert, and either panics or BUGs, depending on mount options. |
| */ |
| __cold |
| void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function, |
| unsigned int line, int errno, const char *fmt, ...) |
| { |
| char *s_id = "<unknown>"; |
| const char *errstr; |
| struct va_format vaf = { .fmt = fmt }; |
| va_list args; |
| |
| if (fs_info) |
| s_id = fs_info->sb->s_id; |
| |
| va_start(args, fmt); |
| vaf.va = &args; |
| |
| errstr = btrfs_decode_error(errno); |
| if (fs_info && (fs_info->mount_opt & BTRFS_MOUNT_PANIC_ON_FATAL_ERROR)) |
| panic(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (errno=%d %s)\n", |
| s_id, function, line, &vaf, errno, errstr); |
| |
| btrfs_crit(fs_info, "panic in %s:%d: %pV (errno=%d %s)", |
| function, line, &vaf, errno, errstr); |
| va_end(args); |
| /* Caller calls BUG() */ |
| } |
| |
| static void btrfs_put_super(struct super_block *sb) |
| { |
| close_ctree(btrfs_sb(sb)->tree_root); |
| } |
| |
| enum { |
| Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum, |
| Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, |
| Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, |
| Opt_compress_type, Opt_compress_force, Opt_compress_force_type, |
| Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard, |
| Opt_space_cache, Opt_space_cache_version, Opt_clear_cache, |
| Opt_user_subvol_rm_allowed, Opt_enospc_debug, Opt_subvolrootid, |
| Opt_defrag, Opt_inode_cache, Opt_no_space_cache, Opt_recovery, |
| Opt_skip_balance, Opt_check_integrity, |
| Opt_check_integrity_including_extent_data, |
| Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree, |
| Opt_commit_interval, Opt_barrier, Opt_nodefrag, Opt_nodiscard, |
| Opt_noenospc_debug, Opt_noflushoncommit, Opt_acl, Opt_datacow, |
| Opt_datasum, Opt_treelog, Opt_noinode_cache, Opt_usebackuproot, |
| Opt_nologreplay, Opt_norecovery, |
| #ifdef CONFIG_BTRFS_DEBUG |
| Opt_fragment_data, Opt_fragment_metadata, Opt_fragment_all, |
| #endif |
| Opt_err, |
| }; |
| |
| static const match_table_t tokens = { |
| {Opt_degraded, "degraded"}, |
| {Opt_subvol, "subvol=%s"}, |
| {Opt_subvolid, "subvolid=%s"}, |
| {Opt_device, "device=%s"}, |
| {Opt_nodatasum, "nodatasum"}, |
| {Opt_datasum, "datasum"}, |
| {Opt_nodatacow, "nodatacow"}, |
| {Opt_datacow, "datacow"}, |
| {Opt_nobarrier, "nobarrier"}, |
| {Opt_barrier, "barrier"}, |
| {Opt_max_inline, "max_inline=%s"}, |
| {Opt_alloc_start, "alloc_start=%s"}, |
| {Opt_thread_pool, "thread_pool=%d"}, |
| {Opt_compress, "compress"}, |
| {Opt_compress_type, "compress=%s"}, |
| {Opt_compress_force, "compress-force"}, |
| {Opt_compress_force_type, "compress-force=%s"}, |
| {Opt_ssd, "ssd"}, |
| {Opt_ssd_spread, "ssd_spread"}, |
| {Opt_nossd, "nossd"}, |
| {Opt_acl, "acl"}, |
| {Opt_noacl, "noacl"}, |
| {Opt_notreelog, "notreelog"}, |
| {Opt_treelog, "treelog"}, |
| {Opt_nologreplay, "nologreplay"}, |
| {Opt_norecovery, "norecovery"}, |
| {Opt_flushoncommit, "flushoncommit"}, |
| {Opt_noflushoncommit, "noflushoncommit"}, |
| {Opt_ratio, "metadata_ratio=%d"}, |
| {Opt_discard, "discard"}, |
| {Opt_nodiscard, "nodiscard"}, |
| {Opt_space_cache, "space_cache"}, |
| {Opt_space_cache_version, "space_cache=%s"}, |
| {Opt_clear_cache, "clear_cache"}, |
| {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, |
| {Opt_enospc_debug, "enospc_debug"}, |
| {Opt_noenospc_debug, "noenospc_debug"}, |
| {Opt_subvolrootid, "subvolrootid=%d"}, |
| {Opt_defrag, "autodefrag"}, |
| {Opt_nodefrag, "noautodefrag"}, |
| {Opt_inode_cache, "inode_cache"}, |
| {Opt_noinode_cache, "noinode_cache"}, |
| {Opt_no_space_cache, "nospace_cache"}, |
| {Opt_recovery, "recovery"}, /* deprecated */ |
| {Opt_usebackuproot, "usebackuproot"}, |
| {Opt_skip_balance, "skip_balance"}, |
| {Opt_check_integrity, "check_int"}, |
| {Opt_check_integrity_including_extent_data, "check_int_data"}, |
| {Opt_check_integrity_print_mask, "check_int_print_mask=%d"}, |
| {Opt_rescan_uuid_tree, "rescan_uuid_tree"}, |
| {Opt_fatal_errors, "fatal_errors=%s"}, |
| {Opt_commit_interval, "commit=%d"}, |
| #ifdef CONFIG_BTRFS_DEBUG |
| {Opt_fragment_data, "fragment=data"}, |
| {Opt_fragment_metadata, "fragment=metadata"}, |
| {Opt_fragment_all, "fragment=all"}, |
| #endif |
| {Opt_err, NULL}, |
| }; |
| |
| /* |
| * Regular mount options parser. Everything that is needed only when |
| * reading in a new superblock is parsed here. |
| * XXX JDM: This needs to be cleaned up for remount. |
| */ |
| int btrfs_parse_options(struct btrfs_root *root, char *options, |
| unsigned long new_flags) |
| { |
| struct btrfs_fs_info *info = root->fs_info; |
| substring_t args[MAX_OPT_ARGS]; |
| char *p, *num, *orig = NULL; |
| u64 cache_gen; |
| int intarg; |
| int ret = 0; |
| char *compress_type; |
| bool compress_force = false; |
| enum btrfs_compression_type saved_compress_type; |
| bool saved_compress_force; |
| int no_compress = 0; |
| |
| cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy); |
| if (btrfs_fs_compat_ro(root->fs_info, FREE_SPACE_TREE)) |
| btrfs_set_opt(info->mount_opt, FREE_SPACE_TREE); |
| else if (cache_gen) |
| btrfs_set_opt(info->mount_opt, SPACE_CACHE); |
| |
| /* |
| * Even the options are empty, we still need to do extra check |
| * against new flags |
| */ |
| if (!options) |
| goto check; |
| |
| /* |
| * strsep changes the string, duplicate it because parse_options |
| * gets called twice |
| */ |
| options = kstrdup(options, GFP_NOFS); |
| if (!options) |
| return -ENOMEM; |
| |
| orig = options; |
| |
| while ((p = strsep(&options, ",")) != NULL) { |
| int token; |
| if (!*p) |
| continue; |
| |
| token = match_token(p, tokens, args); |
| switch (token) { |
| case Opt_degraded: |
| btrfs_info(root->fs_info, "allowing degraded mounts"); |
| btrfs_set_opt(info->mount_opt, DEGRADED); |
| break; |
| case Opt_subvol: |
| case Opt_subvolid: |
| case Opt_subvolrootid: |
| case Opt_device: |
| /* |
| * These are parsed by btrfs_parse_early_options |
| * and can be happily ignored here. |
| */ |
| break; |
| case Opt_nodatasum: |
| btrfs_set_and_info(root, NODATASUM, |
| "setting nodatasum"); |
| break; |
| case Opt_datasum: |
| if (btrfs_test_opt(root, NODATASUM)) { |
| if (btrfs_test_opt(root, NODATACOW)) |
| btrfs_info(root->fs_info, "setting datasum, datacow enabled"); |
| else |
| btrfs_info(root->fs_info, "setting datasum"); |
| } |
| btrfs_clear_opt(info->mount_opt, NODATACOW); |
| btrfs_clear_opt(info->mount_opt, NODATASUM); |
| break; |
| case Opt_nodatacow: |
| if (!btrfs_test_opt(root, NODATACOW)) { |
| if (!btrfs_test_opt(root, COMPRESS) || |
| !btrfs_test_opt(root, FORCE_COMPRESS)) { |
| btrfs_info(root->fs_info, |
| "setting nodatacow, compression disabled"); |
| } else { |
| btrfs_info(root->fs_info, "setting nodatacow"); |
| } |
| } |
| btrfs_clear_opt(info->mount_opt, COMPRESS); |
| btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); |
| btrfs_set_opt(info->mount_opt, NODATACOW); |
| btrfs_set_opt(info->mount_opt, NODATASUM); |
| break; |
| case Opt_datacow: |
| btrfs_clear_and_info(root, NODATACOW, |
| "setting datacow"); |
| break; |
| case Opt_compress_force: |
| case Opt_compress_force_type: |
| compress_force = true; |
| /* Fallthrough */ |
| case Opt_compress: |
| case Opt_compress_type: |
| saved_compress_type = btrfs_test_opt(root, COMPRESS) ? |
| info->compress_type : BTRFS_COMPRESS_NONE; |
| saved_compress_force = |
| btrfs_test_opt(root, FORCE_COMPRESS); |
| if (token == Opt_compress || |
| token == Opt_compress_force || |
| strcmp(args[0].from, "zlib") == 0) { |
| compress_type = "zlib"; |
| info->compress_type = BTRFS_COMPRESS_ZLIB; |
| btrfs_set_opt(info->mount_opt, COMPRESS); |
| btrfs_clear_opt(info->mount_opt, NODATACOW); |
| btrfs_clear_opt(info->mount_opt, NODATASUM); |
| no_compress = 0; |
| } else if (strcmp(args[0].from, "lzo") == 0) { |
| compress_type = "lzo"; |
| info->compress_type = BTRFS_COMPRESS_LZO; |
| btrfs_set_opt(info->mount_opt, COMPRESS); |
| btrfs_clear_opt(info->mount_opt, NODATACOW); |
| btrfs_clear_opt(info->mount_opt, NODATASUM); |
| btrfs_set_fs_incompat(info, COMPRESS_LZO); |
| no_compress = 0; |
| } else if (strncmp(args[0].from, "no", 2) == 0) { |
| compress_type = "no"; |
| btrfs_clear_opt(info->mount_opt, COMPRESS); |
| btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); |
| compress_force = false; |
| no_compress++; |
| } else { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (compress_force) { |
| btrfs_set_opt(info->mount_opt, FORCE_COMPRESS); |
| } else { |
| /* |
| * If we remount from compress-force=xxx to |
| * compress=xxx, we need clear FORCE_COMPRESS |
| * flag, otherwise, there is no way for users |
| * to disable forcible compression separately. |
| */ |
| btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); |
| } |
| if ((btrfs_test_opt(root, COMPRESS) && |
| (info->compress_type != saved_compress_type || |
| compress_force != saved_compress_force)) || |
| (!btrfs_test_opt(root, COMPRESS) && |
| no_compress == 1)) { |
| btrfs_info(root->fs_info, |
| "%s %s compression", |
| (compress_force) ? "force" : "use", |
| compress_type); |
| } |
| compress_force = false; |
| break; |
| case Opt_ssd: |
| btrfs_set_and_info(root, SSD, |
| "use ssd allocation scheme"); |
| break; |
| case Opt_ssd_spread: |
| btrfs_set_and_info(root, SSD_SPREAD, |
| "use spread ssd allocation scheme"); |
| btrfs_set_opt(info->mount_opt, SSD); |
| break; |
| case Opt_nossd: |
| btrfs_set_and_info(root, NOSSD, |
| "not using ssd allocation scheme"); |
| btrfs_clear_opt(info->mount_opt, SSD); |
| break; |
| case Opt_barrier: |
| btrfs_clear_and_info(root, NOBARRIER, |
| "turning on barriers"); |
| break; |
| case Opt_nobarrier: |
| btrfs_set_and_info(root, NOBARRIER, |
| "turning off barriers"); |
| break; |
| case Opt_thread_pool: |
| ret = match_int(&args[0], &intarg); |
| if (ret) { |
| goto out; |
| } else if (intarg > 0) { |
| info->thread_pool_size = intarg; |
| } else { |
| ret = -EINVAL; |
| goto out; |
| } |
| break; |
| case Opt_max_inline: |
| num = match_strdup(&args[0]); |
| if (num) { |
| info->max_inline = memparse(num, NULL); |
| kfree(num); |
| |
| if (info->max_inline) { |
| info->max_inline = min_t(u64, |
| info->max_inline, |
| root->sectorsize); |
| } |
| btrfs_info(root->fs_info, "max_inline at %llu", |
| info->max_inline); |
| } else { |
| ret = -ENOMEM; |
| goto out; |
| } |
| break; |
| case Opt_alloc_start: |
| num = match_strdup(&args[0]); |
| if (num) { |
| mutex_lock(&info->chunk_mutex); |
| info->alloc_start = memparse(num, NULL); |
| mutex_unlock(&info->chunk_mutex); |
| kfree(num); |
| btrfs_info(root->fs_info, "allocations start at %llu", |
| info->alloc_start); |
| } else { |
| ret = -ENOMEM; |
| goto out; |
| } |
| break; |
| case Opt_acl: |
| #ifdef CONFIG_BTRFS_FS_POSIX_ACL |
| root->fs_info->sb->s_flags |= MS_POSIXACL; |
| break; |
| #else |
| btrfs_err(root->fs_info, |
| "support for ACL not compiled in!"); |
| ret = -EINVAL; |
| goto out; |
| #endif |
| case Opt_noacl: |
| root->fs_info->sb->s_flags &= ~MS_POSIXACL; |
| break; |
| case Opt_notreelog: |
| btrfs_set_and_info(root, NOTREELOG, |
| "disabling tree log"); |
| break; |
| case Opt_treelog: |
| btrfs_clear_and_info(root, NOTREELOG, |
| "enabling tree log"); |
| break; |
| case Opt_norecovery: |
| case Opt_nologreplay: |
| btrfs_set_and_info(root, NOLOGREPLAY, |
| "disabling log replay at mount time"); |
| break; |
| case Opt_flushoncommit: |
| btrfs_set_and_info(root, FLUSHONCOMMIT, |
| "turning on flush-on-commit"); |
| break; |
| case Opt_noflushoncommit: |
| btrfs_clear_and_info(root, FLUSHONCOMMIT, |
| "turning off flush-on-commit"); |
| break; |
| case Opt_ratio: |
| ret = match_int(&args[0], &intarg); |
| if (ret) { |
| goto out; |
| } else if (intarg >= 0) { |
| info->metadata_ratio = intarg; |
| btrfs_info(root->fs_info, "metadata ratio %d", |
| info->metadata_ratio); |
| } else { |
| ret = -EINVAL; |
| goto out; |
| } |
| break; |
| case Opt_discard: |
| btrfs_set_and_info(root, DISCARD, |
| "turning on discard"); |
| break; |
| case Opt_nodiscard: |
| btrfs_clear_and_info(root, DISCARD, |
| "turning off discard"); |
| break; |
| case Opt_space_cache: |
| case Opt_space_cache_version: |
| if (token == Opt_space_cache || |
| strcmp(args[0].from, "v1") == 0) { |
| btrfs_clear_opt(root->fs_info->mount_opt, |
| FREE_SPACE_TREE); |
| btrfs_set_and_info(root, SPACE_CACHE, |
| "enabling disk space caching"); |
| } else if (strcmp(args[0].from, "v2") == 0) { |
| btrfs_clear_opt(root->fs_info->mount_opt, |
| SPACE_CACHE); |
| btrfs_set_and_info(root, FREE_SPACE_TREE, |
| "enabling free space tree"); |
| } else { |
| ret = -EINVAL; |
| goto out; |
| } |
| break; |
| case Opt_rescan_uuid_tree: |
| btrfs_set_opt(info->mount_opt, RESCAN_UUID_TREE); |
| break; |
| case Opt_no_space_cache: |
| if (btrfs_test_opt(root, SPACE_CACHE)) { |
| btrfs_clear_and_info(root, SPACE_CACHE, |
| "disabling disk space caching"); |
| } |
| if (btrfs_test_opt(root, FREE_SPACE_TREE)) { |
| btrfs_clear_and_info(root, FREE_SPACE_TREE, |
| "disabling free space tree"); |
| } |
| break; |
| case Opt_inode_cache: |
| btrfs_set_pending_and_info(info, INODE_MAP_CACHE, |
| "enabling inode map caching"); |
| break; |
| case Opt_noinode_cache: |
| btrfs_clear_pending_and_info(info, INODE_MAP_CACHE, |
| "disabling inode map caching"); |
| break; |
| case Opt_clear_cache: |
| btrfs_set_and_info(root, CLEAR_CACHE, |
| "force clearing of disk cache"); |
| break; |
| case Opt_user_subvol_rm_allowed: |
| btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); |
| break; |
| case Opt_enospc_debug: |
| btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG); |
| break; |
| case Opt_noenospc_debug: |
| btrfs_clear_opt(info->mount_opt, ENOSPC_DEBUG); |
| break; |
| case Opt_defrag: |
| btrfs_set_and_info(root, AUTO_DEFRAG, |
| "enabling auto defrag"); |
| break; |
| case Opt_nodefrag: |
| btrfs_clear_and_info(root, AUTO_DEFRAG, |
| "disabling auto defrag"); |
| break; |
| case Opt_recovery: |
| btrfs_warn(root->fs_info, |
| "'recovery' is deprecated, use 'usebackuproot' instead"); |
| case Opt_usebackuproot: |
| btrfs_info(root->fs_info, |
| "trying to use backup root at mount time"); |
| btrfs_set_opt(info->mount_opt, USEBACKUPROOT); |
| break; |
| case Opt_skip_balance: |
| btrfs_set_opt(info->mount_opt, SKIP_BALANCE); |
| break; |
| #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY |
| case Opt_check_integrity_including_extent_data: |
| btrfs_info(root->fs_info, |
| "enabling check integrity including extent data"); |
| btrfs_set_opt(info->mount_opt, |
| CHECK_INTEGRITY_INCLUDING_EXTENT_DATA); |
| btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY); |
| break; |
| case Opt_check_integrity: |
| btrfs_info(root->fs_info, "enabling check integrity"); |
| btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY); |
| break; |
| case Opt_check_integrity_print_mask: |
| ret = match_int(&args[0], &intarg); |
| if (ret) { |
| goto out; |
| } else if (intarg >= 0) { |
| info->check_integrity_print_mask = intarg; |
| btrfs_info(root->fs_info, "check_integrity_print_mask 0x%x", |
| info->check_integrity_print_mask); |
| } else { |
| ret = -EINVAL; |
| goto out; |
| } |
| break; |
| #else |
| case Opt_check_integrity_including_extent_data: |
| case Opt_check_integrity: |
| case Opt_check_integrity_print_mask: |
| btrfs_err(root->fs_info, |
| "support for check_integrity* not compiled in!"); |
| ret = -EINVAL; |
| goto out; |
| #endif |
| case Opt_fatal_errors: |
| if (strcmp(args[0].from, "panic") == 0) |
| btrfs_set_opt(info->mount_opt, |
| PANIC_ON_FATAL_ERROR); |
| else if (strcmp(args[0].from, "bug") == 0) |
| btrfs_clear_opt(info->mount_opt, |
| PANIC_ON_FATAL_ERROR); |
| else { |
| ret = -EINVAL; |
| goto out; |
| } |
| break; |
| case Opt_commit_interval: |
| intarg = 0; |
| ret = match_int(&args[0], &intarg); |
| if (ret < 0) { |
| btrfs_err(root->fs_info, "invalid commit interval"); |
| ret = -EINVAL; |
| goto out; |
| } |
| if (intarg > 0) { |
| if (intarg > 300) { |
| btrfs_warn(root->fs_info, "excessive commit interval %d", |
| intarg); |
| } |
| info->commit_interval = intarg; |
| } else { |
| btrfs_info(root->fs_info, "using default commit interval %ds", |
| BTRFS_DEFAULT_COMMIT_INTERVAL); |
| info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL; |
| } |
| break; |
| #ifdef CONFIG_BTRFS_DEBUG |
| case Opt_fragment_all: |
| btrfs_info(root->fs_info, "fragmenting all space"); |
| btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); |
| btrfs_set_opt(info->mount_opt, FRAGMENT_METADATA); |
| break; |
| case Opt_fragment_metadata: |
| btrfs_info(root->fs_info, "fragmenting metadata"); |
| btrfs_set_opt(info->mount_opt, |
| FRAGMENT_METADATA); |
| break; |
| case Opt_fragment_data: |
| btrfs_info(root->fs_info, "fragmenting data"); |
| btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); |
| break; |
| #endif |
| case Opt_err: |
| btrfs_info(root->fs_info, "unrecognized mount option '%s'", p); |
| ret = -EINVAL; |
| goto out; |
| default: |
| break; |
| } |
| } |
| check: |
| /* |
| * Extra check for current option against current flag |
| */ |
| if (btrfs_test_opt(root, NOLOGREPLAY) && !(new_flags & MS_RDONLY)) { |
| btrfs_err(root->fs_info, |
| "nologreplay must be used with ro mount option"); |
| ret = -EINVAL; |
| } |
| out: |
| if (btrfs_fs_compat_ro(root->fs_info, FREE_SPACE_TREE) && |
| !btrfs_test_opt(root, FREE_SPACE_TREE) && |
| !btrfs_test_opt(root, CLEAR_CACHE)) { |
| btrfs_err(root->fs_info, "cannot disable free space tree"); |
| ret = -EINVAL; |
| |
| } |
| if (!ret && btrfs_test_opt(root, SPACE_CACHE)) |
| btrfs_info(root->fs_info, "disk space caching is enabled"); |
| if (!ret && btrfs_test_opt(root, FREE_SPACE_TREE)) |
| btrfs_info(root->fs_info, "using free space tree"); |
| kfree(orig); |
| return ret; |
| } |
| |
| /* |
| * Parse mount options that are required early in the mount process. |
| * |
| * All other options will be parsed on much later in the mount process and |
| * only when we need to allocate a new super block. |
| */ |
| static int btrfs_parse_early_options(const char *options, fmode_t flags, |
| void *holder, char **subvol_name, u64 *subvol_objectid, |
| struct btrfs_fs_devices **fs_devices) |
| { |
| substring_t args[MAX_OPT_ARGS]; |
| char *device_name, *opts, *orig, *p; |
| char *num = NULL; |
| int error = 0; |
| |
| if (!options) |
| return 0; |
| |
| /* |
| * strsep changes the string, duplicate it because parse_options |
| * gets called twice |
| */ |
| opts = kstrdup(options, GFP_KERNEL); |
| if (!opts) |
| return -ENOMEM; |
| orig = opts; |
| |
| while ((p = strsep(&opts, ",")) != NULL) { |
| int token; |
| if (!*p) |
| continue; |
| |
| token = match_token(p, tokens, args); |
| switch (token) { |
| case Opt_subvol: |
| kfree(*subvol_name); |
| *subvol_name = match_strdup(&args[0]); |
| if (!*subvol_name) { |
| error = -ENOMEM; |
| goto out; |
| } |
| break; |
| case Opt_subvolid: |
| num = match_strdup(&args[0]); |
| if (num) { |
| *subvol_objectid = memparse(num, NULL); |
| kfree(num); |
| /* we want the original fs_tree */ |
| if (!*subvol_objectid) |
| *subvol_objectid = |
| BTRFS_FS_TREE_OBJECTID; |
| } else { |
| error = -EINVAL; |
| goto out; |
| } |
| break; |
| case Opt_subvolrootid: |
| printk(KERN_WARNING |
| "BTRFS: 'subvolrootid' mount option is deprecated and has " |
| "no effect\n"); |
| break; |
| case Opt_device: |
| device_name = match_strdup(&args[0]); |
| if (!device_name) { |
| error = -ENOMEM; |
| goto out; |
| } |
| error = btrfs_scan_one_device(device_name, |
| flags, holder, fs_devices); |
| kfree(device_name); |
| if (error) |
| goto out; |
| break; |
| default: |
| break; |
| } |
| } |
| |
| out: |
| kfree(orig); |
| return error; |
| } |
| |
| static char *get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, |
| u64 subvol_objectid) |
| { |
| struct btrfs_root *root = fs_info->tree_root; |
| struct btrfs_root *fs_root; |
| struct btrfs_root_ref *root_ref; |
| struct btrfs_inode_ref *inode_ref; |
| struct btrfs_key key; |
| struct btrfs_path *path = NULL; |
| char *name = NULL, *ptr; |
| u64 dirid; |
| int len; |
| int ret; |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| ret = -ENOMEM; |
| goto err; |
| } |
| path->leave_spinning = 1; |
| |
| name = kmalloc(PATH_MAX, GFP_NOFS); |
| if (!name) { |
| ret = -ENOMEM; |
| goto err; |
| } |
| ptr = name + PATH_MAX - 1; |
| ptr[0] = '\0'; |
| |
| /* |
| * Walk up the subvolume trees in the tree of tree roots by root |
| * backrefs until we hit the top-level subvolume. |
| */ |
| while (subvol_objectid != BTRFS_FS_TREE_OBJECTID) { |
| key.objectid = subvol_objectid; |
| key.type = BTRFS_ROOT_BACKREF_KEY; |
| key.offset = (u64)-1; |
| |
| ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| if (ret < 0) { |
| goto err; |
| } else if (ret > 0) { |
| ret = btrfs_previous_item(root, path, subvol_objectid, |
| BTRFS_ROOT_BACKREF_KEY); |
| if (ret < 0) { |
| goto err; |
| } else if (ret > 0) { |
| ret = -ENOENT; |
| goto err; |
| } |
| } |
| |
| btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); |
| subvol_objectid = key.offset; |
| |
| root_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| struct btrfs_root_ref); |
| len = btrfs_root_ref_name_len(path->nodes[0], root_ref); |
| ptr -= len + 1; |
| if (ptr < name) { |
| ret = -ENAMETOOLONG; |
| goto err; |
| } |
| read_extent_buffer(path->nodes[0], ptr + 1, |
| (unsigned long)(root_ref + 1), len); |
| ptr[0] = '/'; |
| dirid = btrfs_root_ref_dirid(path->nodes[0], root_ref); |
| btrfs_release_path(path); |
| |
| key.objectid = subvol_objectid; |
| key.type = BTRFS_ROOT_ITEM_KEY; |
| key.offset = (u64)-1; |
| fs_root = btrfs_read_fs_root_no_name(fs_info, &key); |
| if (IS_ERR(fs_root)) { |
| ret = PTR_ERR(fs_root); |
| goto err; |
| } |
| |
| /* |
| * Walk up the filesystem tree by inode refs until we hit the |
| * root directory. |
| */ |
| while (dirid != BTRFS_FIRST_FREE_OBJECTID) { |
| key.objectid = dirid; |
| key.type = BTRFS_INODE_REF_KEY; |
| key.offset = (u64)-1; |
| |
| ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0); |
| if (ret < 0) { |
| goto err; |
| } else if (ret > 0) { |
| ret = btrfs_previous_item(fs_root, path, dirid, |
| BTRFS_INODE_REF_KEY); |
| if (ret < 0) { |
| goto err; |
| } else if (ret > 0) { |
| ret = -ENOENT; |
| goto err; |
| } |
| } |
| |
| btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); |
| dirid = key.offset; |
| |
| inode_ref = btrfs_item_ptr(path->nodes[0], |
| path->slots[0], |
| struct btrfs_inode_ref); |
| len = btrfs_inode_ref_name_len(path->nodes[0], |
| inode_ref); |
| ptr -= len + 1; |
| if (ptr < name) { |
| ret = -ENAMETOOLONG; |
| goto err; |
| } |
| read_extent_buffer(path->nodes[0], ptr + 1, |
| (unsigned long)(inode_ref + 1), len); |
| ptr[0] = '/'; |
| btrfs_release_path(path); |
| } |
| } |
| |
| btrfs_free_path(path); |
| if (ptr == name + PATH_MAX - 1) { |
| name[0] = '/'; |
| name[1] = '\0'; |
| } else { |
| memmove(name, ptr, name + PATH_MAX - ptr); |
| } |
| return name; |
| |
| err: |
| btrfs_free_path(path); |
| kfree(name); |
| return ERR_PTR(ret); |
| } |
| |
| static int get_default_subvol_objectid(struct btrfs_fs_info *fs_info, u64 *objectid) |
| { |
| struct btrfs_root *root = fs_info->tree_root; |
| struct btrfs_dir_item *di; |
| struct btrfs_path *path; |
| struct btrfs_key location; |
| u64 dir_id; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| path->leave_spinning = 1; |
| |
| /* |
| * Find the "default" dir item which points to the root item that we |
| * will mount by default if we haven't been given a specific subvolume |
| * to mount. |
| */ |
| dir_id = btrfs_super_root_dir(fs_info->super_copy); |
| di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0); |
| if (IS_ERR(di)) { |
| btrfs_free_path(path); |
| return PTR_ERR(di); |
| } |
| if (!di) { |
| /* |
| * Ok the default dir item isn't there. This is weird since |
| * it's always been there, but don't freak out, just try and |
| * mount the top-level subvolume. |
| */ |
| btrfs_free_path(path); |
| *objectid = BTRFS_FS_TREE_OBJECTID; |
| return 0; |
| } |
| |
| btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); |
| btrfs_free_path(path); |
| *objectid = location.objectid; |
| return 0; |
| } |
| |
| static int btrfs_fill_super(struct super_block *sb, |
| struct btrfs_fs_devices *fs_devices, |
| void *data, int silent) |
| { |
| struct inode *inode; |
| struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| struct btrfs_key key; |
| int err; |
| |
| sb->s_maxbytes = MAX_LFS_FILESIZE; |
| sb->s_magic = BTRFS_SUPER_MAGIC; |
| sb->s_op = &btrfs_super_ops; |
| sb->s_d_op = &btrfs_dentry_operations; |
| sb->s_export_op = &btrfs_export_ops; |
| sb->s_xattr = btrfs_xattr_handlers; |
| sb->s_time_gran = 1; |
| #ifdef CONFIG_BTRFS_FS_POSIX_ACL |
| sb->s_flags |= MS_POSIXACL; |
| #endif |
| sb->s_flags |= MS_I_VERSION; |
| sb->s_iflags |= SB_I_CGROUPWB; |
| err = open_ctree(sb, fs_devices, (char *)data); |
| if (err) { |
| printk(KERN_ERR "BTRFS: open_ctree failed\n"); |
| return err; |
| } |
| |
| key.objectid = BTRFS_FIRST_FREE_OBJECTID; |
| key.type = BTRFS_INODE_ITEM_KEY; |
| key.offset = 0; |
| inode = btrfs_iget(sb, &key, fs_info->fs_root, NULL); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| goto fail_close; |
| } |
| |
| sb->s_root = d_make_root(inode); |
| if (!sb->s_root) { |
| err = -ENOMEM; |
| goto fail_close; |
| } |
| |
| save_mount_options(sb, data); |
| cleancache_init_fs(sb); |
| sb->s_flags |= MS_ACTIVE; |
| return 0; |
| |
| fail_close: |
| close_ctree(fs_info->tree_root); |
| return err; |
| } |
| |
| int btrfs_sync_fs(struct super_block *sb, int wait) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| struct btrfs_root *root = fs_info->tree_root; |
| |
| trace_btrfs_sync_fs(wait); |
| |
| if (!wait) { |
| filemap_flush(fs_info->btree_inode->i_mapping); |
| return 0; |
| } |
| |
| btrfs_wait_ordered_roots(fs_info, -1, 0, (u64)-1); |
| |
| trans = btrfs_attach_transaction_barrier(root); |
| if (IS_ERR(trans)) { |
| /* no transaction, don't bother */ |
| if (PTR_ERR(trans) == -ENOENT) { |
| /* |
| * Exit unless we have some pending changes |
| * that need to go through commit |
| */ |
| if (fs_info->pending_changes == 0) |
| return 0; |
| /* |
| * A non-blocking test if the fs is frozen. We must not |
| * start a new transaction here otherwise a deadlock |
| * happens. The pending operations are delayed to the |
| * next commit after thawing. |
| */ |
| if (__sb_start_write(sb, SB_FREEZE_WRITE, false)) |
| __sb_end_write(sb, SB_FREEZE_WRITE); |
| else |
| return 0; |
| trans = btrfs_start_transaction(root, 0); |
| } |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| } |
| return btrfs_commit_transaction(trans, root); |
| } |
| |
| static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) |
| { |
| struct btrfs_fs_info *info = btrfs_sb(dentry->d_sb); |
| struct btrfs_root *root = info->tree_root; |
| char *compress_type; |
| |
| if (btrfs_test_opt(root, DEGRADED)) |
| seq_puts(seq, ",degraded"); |
| if (btrfs_test_opt(root, NODATASUM)) |
| seq_puts(seq, ",nodatasum"); |
| if (btrfs_test_opt(root, NODATACOW)) |
| seq_puts(seq, ",nodatacow"); |
| if (btrfs_test_opt(root, NOBARRIER)) |
| seq_puts(seq, ",nobarrier"); |
| if (info->max_inline != BTRFS_DEFAULT_MAX_INLINE) |
| seq_printf(seq, ",max_inline=%llu", info->max_inline); |
| if (info->alloc_start != 0) |
| seq_printf(seq, ",alloc_start=%llu", info->alloc_start); |
| if (info->thread_pool_size != min_t(unsigned long, |
| num_online_cpus() + 2, 8)) |
| seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); |
| if (btrfs_test_opt(root, COMPRESS)) { |
| if (info->compress_type == BTRFS_COMPRESS_ZLIB) |
| compress_type = "zlib"; |
| else |
| compress_type = "lzo"; |
| if (btrfs_test_opt(root, FORCE_COMPRESS)) |
| seq_printf(seq, ",compress-force=%s", compress_type); |
| else |
| seq_printf(seq, ",compress=%s", compress_type); |
| } |
| if (btrfs_test_opt(root, NOSSD)) |
| seq_puts(seq, ",nossd"); |
| if (btrfs_test_opt(root, SSD_SPREAD)) |
| seq_puts(seq, ",ssd_spread"); |
| else if (btrfs_test_opt(root, SSD)) |
| seq_puts(seq, ",ssd"); |
| if (btrfs_test_opt(root, NOTREELOG)) |
| seq_puts(seq, ",notreelog"); |
| if (btrfs_test_opt(root, NOLOGREPLAY)) |
| seq_puts(seq, ",nologreplay"); |
| if (btrfs_test_opt(root, FLUSHONCOMMIT)) |
| seq_puts(seq, ",flushoncommit"); |
| if (btrfs_test_opt(root, DISCARD)) |
| seq_puts(seq, ",discard"); |
| if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) |
| seq_puts(seq, ",noacl"); |
| if (btrfs_test_opt(root, SPACE_CACHE)) |
| seq_puts(seq, ",space_cache"); |
| else if (btrfs_test_opt(root, FREE_SPACE_TREE)) |
| seq_puts(seq, ",space_cache=v2"); |
| else |
| seq_puts(seq, ",nospace_cache"); |
| if (btrfs_test_opt(root, RESCAN_UUID_TREE)) |
| seq_puts(seq, ",rescan_uuid_tree"); |
| if (btrfs_test_opt(root, CLEAR_CACHE)) |
| seq_puts(seq, ",clear_cache"); |
| if (btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) |
| seq_puts(seq, ",user_subvol_rm_allowed"); |
| if (btrfs_test_opt(root, ENOSPC_DEBUG)) |
| seq_puts(seq, ",enospc_debug"); |
| if (btrfs_test_opt(root, AUTO_DEFRAG)) |
| seq_puts(seq, ",autodefrag"); |
| if (btrfs_test_opt(root, INODE_MAP_CACHE)) |
| seq_puts(seq, ",inode_cache"); |
| if (btrfs_test_opt(root, SKIP_BALANCE)) |
| seq_puts(seq, ",skip_balance"); |
| #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY |
| if (btrfs_test_opt(root, CHECK_INTEGRITY_INCLUDING_EXTENT_DATA)) |
| seq_puts(seq, ",check_int_data"); |
| else if (btrfs_test_opt(root, CHECK_INTEGRITY)) |
| seq_puts(seq, ",check_int"); |
| if (info->check_integrity_print_mask) |
| seq_printf(seq, ",check_int_print_mask=%d", |
| info->check_integrity_print_mask); |
| #endif |
| if (info->metadata_ratio) |
| seq_printf(seq, ",metadata_ratio=%d", |
| info->metadata_ratio); |
| if (btrfs_test_opt(root, PANIC_ON_FATAL_ERROR)) |
| seq_puts(seq, ",fatal_errors=panic"); |
| if (info->commit_interval != BTRFS_DEFAULT_COMMIT_INTERVAL) |
| seq_printf(seq, ",commit=%d", info->commit_interval); |
| #ifdef CONFIG_BTRFS_DEBUG |
| if (btrfs_test_opt(root, FRAGMENT_DATA)) |
| seq_puts(seq, ",fragment=data"); |
| if (btrfs_test_opt(root, FRAGMENT_METADATA)) |
| seq_puts(seq, ",fragment=metadata"); |
| #endif |
| seq_printf(seq, ",subvolid=%llu", |
| BTRFS_I(d_inode(dentry))->root->root_key.objectid); |
| seq_puts(seq, ",subvol="); |
| seq_dentry(seq, dentry, " \t\n\\"); |
| return 0; |
| } |
| |
| static int btrfs_test_super(struct super_block *s, void *data) |
| { |
| struct btrfs_fs_info *p = data; |
| struct btrfs_fs_info *fs_info = btrfs_sb(s); |
| |
| return fs_info->fs_devices == p->fs_devices; |
| } |
| |
| static int btrfs_set_super(struct super_block *s, void *data) |
| { |
| int err = set_anon_super(s, data); |
| if (!err) |
| s->s_fs_info = data; |
| return err; |
| } |
| |
| /* |
| * subvolumes are identified by ino 256 |
| */ |
| static inline int is_subvolume_inode(struct inode *inode) |
| { |
| if (inode && inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) |
| return 1; |
| return 0; |
| } |
| |
| /* |
| * This will add subvolid=0 to the argument string while removing any subvol= |
| * and subvolid= arguments to make sure we get the top-level root for path |
| * walking to the subvol we want. |
| */ |
| static char *setup_root_args(char *args) |
| { |
| char *buf, *dst, *sep; |
| |
| if (!args) |
| return kstrdup("subvolid=0", GFP_NOFS); |
| |
| /* The worst case is that we add ",subvolid=0" to the end. */ |
| buf = dst = kmalloc(strlen(args) + strlen(",subvolid=0") + 1, GFP_NOFS); |
| if (!buf) |
| return NULL; |
| |
| while (1) { |
| sep = strchrnul(args, ','); |
| if (!strstarts(args, "subvol=") && |
| !strstarts(args, "subvolid=")) { |
| memcpy(dst, args, sep - args); |
| dst += sep - args; |
| *dst++ = ','; |
| } |
| if (*sep) |
| args = sep + 1; |
| else |
| break; |
| } |
| strcpy(dst, "subvolid=0"); |
| |
| return buf; |
| } |
| |
| static struct dentry *mount_subvol(const char *subvol_name, u64 subvol_objectid, |
| int flags, const char *device_name, |
| char *data) |
| { |
| struct dentry *root; |
| struct vfsmount *mnt = NULL; |
| char *newargs; |
| int ret; |
| |
| newargs = setup_root_args(data); |
| if (!newargs) { |
| root = ERR_PTR(-ENOMEM); |
| goto out; |
| } |
| |
| mnt = vfs_kern_mount(&btrfs_fs_type, flags, device_name, newargs); |
| if (PTR_ERR_OR_ZERO(mnt) == -EBUSY) { |
| if (flags & MS_RDONLY) { |
| mnt = vfs_kern_mount(&btrfs_fs_type, flags & ~MS_RDONLY, |
| device_name, newargs); |
| } else { |
| mnt = vfs_kern_mount(&btrfs_fs_type, flags | MS_RDONLY, |
| device_name, newargs); |
| if (IS_ERR(mnt)) { |
| root = ERR_CAST(mnt); |
| mnt = NULL; |
| goto out; |
| } |
| |
| down_write(&mnt->mnt_sb->s_umount); |
| ret = btrfs_remount(mnt->mnt_sb, &flags, NULL); |
| up_write(&mnt->mnt_sb->s_umount); |
| if (ret < 0) { |
| root = ERR_PTR(ret); |
| goto out; |
| } |
| } |
| } |
| if (IS_ERR(mnt)) { |
| root = ERR_CAST(mnt); |
| mnt = NULL; |
| goto out; |
| } |
| |
| if (!subvol_name) { |
| if (!subvol_objectid) { |
| ret = get_default_subvol_objectid(btrfs_sb(mnt->mnt_sb), |
| &subvol_objectid); |
| if (ret) { |
| root = ERR_PTR(ret); |
| goto out; |
| } |
| } |
| subvol_name = get_subvol_name_from_objectid(btrfs_sb(mnt->mnt_sb), |
| subvol_objectid); |
| if (IS_ERR(subvol_name)) { |
| root = ERR_CAST(subvol_name); |
| subvol_name = NULL; |
| goto out; |
| } |
| |
| } |
| |
| root = mount_subtree(mnt, subvol_name); |
| /* mount_subtree() drops our reference on the vfsmount. */ |
| mnt = NULL; |
| |
| if (!IS_ERR(root)) { |
| struct super_block *s = root->d_sb; |
| struct inode *root_inode = d_inode(root); |
| u64 root_objectid = BTRFS_I(root_inode)->root->root_key.objectid; |
| |
| ret = 0; |
| if (!is_subvolume_inode(root_inode)) { |
| pr_err("BTRFS: '%s' is not a valid subvolume\n", |
| subvol_name); |
| ret = -EINVAL; |
| } |
| if (subvol_objectid && root_objectid != subvol_objectid) { |
| /* |
| * This will also catch a race condition where a |
| * subvolume which was passed by ID is renamed and |
| * another subvolume is renamed over the old location. |
| */ |
| pr_err("BTRFS: subvol '%s' does not match subvolid %llu\n", |
| subvol_name, subvol_objectid); |
| ret = -EINVAL; |
| } |
| if (ret) { |
| dput(root); |
| root = ERR_PTR(ret); |
| deactivate_locked_super(s); |
| } |
| } |
| |
| out: |
| mntput(mnt); |
| kfree(newargs); |
| kfree(subvol_name); |
| return root; |
| } |
| |
| static int parse_security_options(char *orig_opts, |
| struct security_mnt_opts *sec_opts) |
| { |
| char *secdata = NULL; |
| int ret = 0; |
| |
| secdata = alloc_secdata(); |
| if (!secdata) |
| return -ENOMEM; |
| ret = security_sb_copy_data(orig_opts, secdata); |
| if (ret) { |
| free_secdata(secdata); |
| return ret; |
| } |
| ret = security_sb_parse_opts_str(secdata, sec_opts); |
| free_secdata(secdata); |
| return ret; |
| } |
| |
| static int setup_security_options(struct btrfs_fs_info *fs_info, |
| struct super_block *sb, |
| struct security_mnt_opts *sec_opts) |
| { |
| int ret = 0; |
| |
| /* |
| * Call security_sb_set_mnt_opts() to check whether new sec_opts |
| * is valid. |
| */ |
| ret = security_sb_set_mnt_opts(sb, sec_opts, 0, NULL); |
| if (ret) |
| return ret; |
| |
| #ifdef CONFIG_SECURITY |
| if (!fs_info->security_opts.num_mnt_opts) { |
| /* first time security setup, copy sec_opts to fs_info */ |
| memcpy(&fs_info->security_opts, sec_opts, sizeof(*sec_opts)); |
| } else { |
| /* |
| * Since SELinux (the only one supporting security_mnt_opts) |
| * does NOT support changing context during remount/mount of |
| * the same sb, this must be the same or part of the same |
| * security options, just free it. |
| */ |
| security_free_mnt_opts(sec_opts); |
| } |
| #endif |
| return ret; |
| } |
| |
| /* |
| * Find a superblock for the given device / mount point. |
| * |
| * Note: This is based on get_sb_bdev from fs/super.c with a few additions |
| * for multiple device setup. Make sure to keep it in sync. |
| */ |
| static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, |
| const char *device_name, void *data) |
| { |
| struct block_device *bdev = NULL; |
| struct super_block *s; |
| struct btrfs_fs_devices *fs_devices = NULL; |
| struct btrfs_fs_info *fs_info = NULL; |
| struct security_mnt_opts new_sec_opts; |
| fmode_t mode = FMODE_READ; |
| char *subvol_name = NULL; |
| u64 subvol_objectid = 0; |
| int error = 0; |
| |
| if (!(flags & MS_RDONLY)) |
| mode |= FMODE_WRITE; |
| |
| error = btrfs_parse_early_options(data, mode, fs_type, |
| &subvol_name, &subvol_objectid, |
| &fs_devices); |
| if (error) { |
| kfree(subvol_name); |
| return ERR_PTR(error); |
| } |
| |
| if (subvol_name || subvol_objectid != BTRFS_FS_TREE_OBJECTID) { |
| /* mount_subvol() will free subvol_name. */ |
| return mount_subvol(subvol_name, subvol_objectid, flags, |
| device_name, data); |
| } |
| |
| security_init_mnt_opts(&new_sec_opts); |
| if (data) { |
| error = parse_security_options(data, &new_sec_opts); |
| if (error) |
| return ERR_PTR(error); |
| } |
| |
| error = btrfs_scan_one_device(device_name, mode, fs_type, &fs_devices); |
| if (error) |
| goto error_sec_opts; |
| |
| /* |
| * Setup a dummy root and fs_info for test/set super. This is because |
| * we don't actually fill this stuff out until open_ctree, but we need |
| * it for searching for existing supers, so this lets us do that and |
| * then open_ctree will properly initialize everything later. |
| */ |
| fs_info = kzalloc(sizeof(struct btrfs_fs_info), GFP_NOFS); |
| if (!fs_info) { |
| error = -ENOMEM; |
| goto error_sec_opts; |
| } |
| |
| fs_info->fs_devices = fs_devices; |
| |
| fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_NOFS); |
| fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_NOFS); |
| security_init_mnt_opts(&fs_info->security_opts); |
| if (!fs_info->super_copy || !fs_info->super_for_commit) { |
| error = -ENOMEM; |
| goto error_fs_info; |
| } |
| |
| error = btrfs_open_devices(fs_devices, mode, fs_type); |
| if (error) |
| goto error_fs_info; |
| |
| if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
| error = -EACCES; |
| goto error_close_devices; |
| } |
| |
| bdev = fs_devices->latest_bdev; |
| s = sget(fs_type, btrfs_test_super, btrfs_set_super, flags | MS_NOSEC, |
| fs_info); |
| if (IS_ERR(s)) { |
| error = PTR_ERR(s); |
| goto error_close_devices; |
| } |
| |
| if (s->s_root) { |
| btrfs_close_devices(fs_devices); |
| free_fs_info(fs_info); |
| if ((flags ^ s->s_flags) & MS_RDONLY) |
| error = -EBUSY; |
| } else { |
| snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev); |
| btrfs_sb(s)->bdev_holder = fs_type; |
| error = btrfs_fill_super(s, fs_devices, data, |
| flags & MS_SILENT ? 1 : 0); |
| } |
| if (error) { |
| deactivate_locked_super(s); |
| goto error_sec_opts; |
| } |
| |
| fs_info = btrfs_sb(s); |
| error = setup_security_options(fs_info, s, &new_sec_opts); |
| if (error) { |
| deactivate_locked_super(s); |
| goto error_sec_opts; |
| } |
| |
| return dget(s->s_root); |
| |
| error_close_devices: |
| btrfs_close_devices(fs_devices); |
| error_fs_info: |
| free_fs_info(fs_info); |
| error_sec_opts: |
| security_free_mnt_opts(&new_sec_opts); |
| return ERR_PTR(error); |
| } |
| |
| static void btrfs_resize_thread_pool(struct btrfs_fs_info *fs_info, |
| int new_pool_size, int old_pool_size) |
| { |
| if (new_pool_size == old_pool_size) |
| return; |
| |
| fs_info->thread_pool_size = new_pool_size; |
| |
| btrfs_info(fs_info, "resize thread pool %d -> %d", |
| old_pool_size, new_pool_size); |
| |
| btrfs_workqueue_set_max(fs_info->workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->delalloc_workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->submit_workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->caching_workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->endio_workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->endio_meta_workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->endio_meta_write_workers, |
| new_pool_size); |
| btrfs_workqueue_set_max(fs_info->endio_write_workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->endio_freespace_worker, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->delayed_workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->readahead_workers, new_pool_size); |
| btrfs_workqueue_set_max(fs_info->scrub_wr_completion_workers, |
| new_pool_size); |
| } |
| |
| static inline void btrfs_remount_prepare(struct btrfs_fs_info *fs_info) |
| { |
| set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); |
| } |
| |
| static inline void btrfs_remount_begin(struct btrfs_fs_info *fs_info, |
| unsigned long old_opts, int flags) |
| { |
| if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && |
| (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || |
| (flags & MS_RDONLY))) { |
| /* wait for any defraggers to finish */ |
| wait_event(fs_info->transaction_wait, |
| (atomic_read(&fs_info->defrag_running) == 0)); |
| if (flags & MS_RDONLY) |
| sync_filesystem(fs_info->sb); |
| } |
| } |
| |
| static inline void btrfs_remount_cleanup(struct btrfs_fs_info *fs_info, |
| unsigned long old_opts) |
| { |
| /* |
| * We need to cleanup all defragable inodes if the autodefragment is |
| * close or the filesystem is read only. |
| */ |
| if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && |
| (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || |
| (fs_info->sb->s_flags & MS_RDONLY))) { |
| btrfs_cleanup_defrag_inodes(fs_info); |
| } |
| |
| clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); |
| } |
| |
| static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
| { |
| struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| struct btrfs_root *root = fs_info->tree_root; |
| unsigned old_flags = sb->s_flags; |
| unsigned long old_opts = fs_info->mount_opt; |
| unsigned long old_compress_type = fs_info->compress_type; |
| u64 old_max_inline = fs_info->max_inline; |
| u64 old_alloc_start = fs_info->alloc_start; |
| int old_thread_pool_size = fs_info->thread_pool_size; |
| unsigned int old_metadata_ratio = fs_info->metadata_ratio; |
| int ret; |
| |
| sync_filesystem(sb); |
| btrfs_remount_prepare(fs_info); |
| |
| if (data) { |
| struct security_mnt_opts new_sec_opts; |
| |
| security_init_mnt_opts(&new_sec_opts); |
| ret = parse_security_options(data, &new_sec_opts); |
| if (ret) |
| goto restore; |
| ret = setup_security_options(fs_info, sb, |
| &new_sec_opts); |
| if (ret) { |
| security_free_mnt_opts(&new_sec_opts); |
| goto restore; |
| } |
| } |
| |
| ret = btrfs_parse_options(root, data, *flags); |
| if (ret) { |
| ret = -EINVAL; |
| goto restore; |
| } |
| |
| btrfs_remount_begin(fs_info, old_opts, *flags); |
| btrfs_resize_thread_pool(fs_info, |
| fs_info->thread_pool_size, old_thread_pool_size); |
| |
| if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) |
| goto out; |
| |
| if (*flags & MS_RDONLY) { |
| /* |
| * this also happens on 'umount -rf' or on shutdown, when |
| * the filesystem is busy. |
| */ |
| cancel_work_sync(&fs_info->async_reclaim_work); |
| |
| /* wait for the uuid_scan task to finish */ |
| down(&fs_info->uuid_tree_rescan_sem); |
| /* avoid complains from lockdep et al. */ |
| up(&fs_info->uuid_tree_rescan_sem); |
| |
| sb->s_flags |= MS_RDONLY; |
| |
| /* |
| * Setting MS_RDONLY will put the cleaner thread to |
| * sleep at the next loop if it's already active. |
| * If it's already asleep, we'll leave unused block |
| * groups on disk until we're mounted read-write again |
| * unless we clean them up here. |
| */ |
| btrfs_delete_unused_bgs(fs_info); |
| |
| btrfs_dev_replace_suspend_for_unmount(fs_info); |
| btrfs_scrub_cancel(fs_info); |
| btrfs_pause_balance(fs_info); |
| |
| ret = btrfs_commit_super(root); |
| if (ret) |
| goto restore; |
| } else { |
| if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) { |
| btrfs_err(fs_info, |
| "Remounting read-write after error is not allowed"); |
| ret = -EINVAL; |
| goto restore; |
| } |
| if (fs_info->fs_devices->rw_devices == 0) { |
| ret = -EACCES; |
| goto restore; |
| } |
| |
| if (fs_info->fs_devices->missing_devices > |
| fs_info->num_tolerated_disk_barrier_failures && |
| !(*flags & MS_RDONLY)) { |
| btrfs_warn(fs_info, |
| "too many missing devices, writeable remount is not allowed"); |
| ret = -EACCES; |
| goto restore; |
| } |
| |
| if (btrfs_super_log_root(fs_info->super_copy) != 0) { |
| ret = -EINVAL; |
| goto restore; |
| } |
| |
| ret = btrfs_cleanup_fs_roots(fs_info); |
| if (ret) |
| goto restore; |
| |
| /* recover relocation */ |
| mutex_lock(&fs_info->cleaner_mutex); |
| ret = btrfs_recover_relocation(root); |
| mutex_unlock(&fs_info->cleaner_mutex); |
| if (ret) |
| goto restore; |
| |
| ret = btrfs_resume_balance_async(fs_info); |
| if (ret) |
| goto restore; |
| |
| ret = btrfs_resume_dev_replace_async(fs_info); |
| if (ret) { |
| btrfs_warn(fs_info, "failed to resume dev_replace"); |
| goto restore; |
| } |
| |
| if (!fs_info->uuid_root) { |
| btrfs_info(fs_info, "creating UUID tree"); |
| ret = btrfs_create_uuid_tree(fs_info); |
| if (ret) { |
| btrfs_warn(fs_info, "failed to create the UUID tree %d", ret); |
| goto restore; |
| } |
| } |
| sb->s_flags &= ~MS_RDONLY; |
| |
| fs_info->open = 1; |
| } |
| out: |
| wake_up_process(fs_info->transaction_kthread); |
| btrfs_remount_cleanup(fs_info, old_opts); |
| return 0; |
| |
| restore: |
| /* We've hit an error - don't reset MS_RDONLY */ |
| if (sb->s_flags & MS_RDONLY) |
| old_flags |= MS_RDONLY; |
| sb->s_flags = old_flags; |
| fs_info->mount_opt = old_opts; |
| fs_info->compress_type = old_compress_type; |
| fs_info->max_inline = old_max_inline; |
| mutex_lock(&fs_info->chunk_mutex); |
| fs_info->alloc_start = old_alloc_start; |
| mutex_unlock(&fs_info->chunk_mutex); |
| btrfs_resize_thread_pool(fs_info, |
| old_thread_pool_size, fs_info->thread_pool_size); |
| fs_info->metadata_ratio = old_metadata_ratio; |
| btrfs_remount_cleanup(fs_info, old_opts); |
| return ret; |
| } |
| |
| /* Used to sort the devices by max_avail(descending sort) */ |
| static int btrfs_cmp_device_free_bytes(const void *dev_info1, |
| const void *dev_info2) |
| { |
| if (((struct btrfs_device_info *)dev_info1)->max_avail > |
| ((struct btrfs_device_info *)dev_info2)->max_avail) |
| return -1; |
| else if (((struct btrfs_device_info *)dev_info1)->max_avail < |
| ((struct btrfs_device_info *)dev_info2)->max_avail) |
| return 1; |
| else |
| return 0; |
| } |
| |
| /* |
| * sort the devices by max_avail, in which max free extent size of each device |
| * is stored.(Descending Sort) |
| */ |
| static inline void btrfs_descending_sort_devices( |
| struct btrfs_device_info *devices, |
| size_t nr_devices) |
| { |
| sort(devices, nr_devices, sizeof(struct btrfs_device_info), |
| btrfs_cmp_device_free_bytes, NULL); |
| } |
| |
| /* |
| * The helper to calc the free space on the devices that can be used to store |
| * file data. |
| */ |
| static int btrfs_calc_avail_data_space(struct btrfs_root *root, u64 *free_bytes) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| struct btrfs_device_info *devices_info; |
| struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; |
| struct btrfs_device *device; |
| u64 skip_space; |
| u64 type; |
| u64 avail_space; |
| u64 used_space; |
| u64 min_stripe_size; |
| int min_stripes = 1, num_stripes = 1; |
| int i = 0, nr_devices; |
| int ret; |
| |
| /* |
| * We aren't under the device list lock, so this is racy-ish, but good |
| * enough for our purposes. |
| */ |
| nr_devices = fs_info->fs_devices->open_devices; |
| if (!nr_devices) { |
| smp_mb(); |
| nr_devices = fs_info->fs_devices->open_devices; |
| ASSERT(nr_devices); |
| if (!nr_devices) { |
| *free_bytes = 0; |
| return 0; |
| } |
| } |
| |
| devices_info = kmalloc_array(nr_devices, sizeof(*devices_info), |
| GFP_NOFS); |
| if (!devices_info) |
| return -ENOMEM; |
| |
| /* calc min stripe number for data space allocation */ |
| type = btrfs_get_alloc_profile(root, 1); |
| if (type & BTRFS_BLOCK_GROUP_RAID0) { |
| min_stripes = 2; |
| num_stripes = nr_devices; |
| } else if (type & BTRFS_BLOCK_GROUP_RAID1) { |
| min_stripes = 2; |
| num_stripes = 2; |
| } else if (type & BTRFS_BLOCK_GROUP_RAID10) { |
| min_stripes = 4; |
| num_stripes = 4; |
| } |
| |
| if (type & BTRFS_BLOCK_GROUP_DUP) |
| min_stripe_size = 2 * BTRFS_STRIPE_LEN; |
| else |
| min_stripe_size = BTRFS_STRIPE_LEN; |
| |
| if (fs_info->alloc_start) |
| mutex_lock(&fs_devices->device_list_mutex); |
| rcu_read_lock(); |
| list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) { |
| if (!device->in_fs_metadata || !device->bdev || |
| device->is_tgtdev_for_dev_replace) |
| continue; |
| |
| if (i >= nr_devices) |
| break; |
| |
| avail_space = device->total_bytes - device->bytes_used; |
| |
| /* align with stripe_len */ |
| avail_space = div_u64(avail_space, BTRFS_STRIPE_LEN); |
| avail_space *= BTRFS_STRIPE_LEN; |
| |
| /* |
| * In order to avoid overwriting the superblock on the drive, |
| * btrfs starts at an offset of at least 1MB when doing chunk |
| * allocation. |
| */ |
| skip_space = SZ_1M; |
| |
| /* user can set the offset in fs_info->alloc_start. */ |
| if (fs_info->alloc_start && |
| fs_info->alloc_start + BTRFS_STRIPE_LEN <= |
| device->total_bytes) { |
| rcu_read_unlock(); |
| skip_space = max(fs_info->alloc_start, skip_space); |
| |
| /* |
| * btrfs can not use the free space in |
| * [0, skip_space - 1], we must subtract it from the |
| * total. In order to implement it, we account the used |
| * space in this range first. |
| */ |
| ret = btrfs_account_dev_extents_size(device, 0, |
| skip_space - 1, |
| &used_space); |
| if (ret) { |
| kfree(devices_info); |
| mutex_unlock(&fs_devices->device_list_mutex); |
| return ret; |
| } |
| |
| rcu_read_lock(); |
| |
| /* calc the free space in [0, skip_space - 1] */ |
| skip_space -= used_space; |
| } |
| |
| /* |
| * we can use the free space in [0, skip_space - 1], subtract |
| * it from the total. |
| */ |
| if (avail_space && avail_space >= skip_space) |
| avail_space -= skip_space; |
| else |
| avail_space = 0; |
| |
| if (avail_space < min_stripe_size) |
| continue; |
| |
| devices_info[i].dev = device; |
| devices_info[i].max_avail = avail_space; |
| |
| i++; |
| } |
| rcu_read_unlock(); |
| if (fs_info->alloc_start) |
| mutex_unlock(&fs_devices->device_list_mutex); |
| |
| nr_devices = i; |
| |
| btrfs_descending_sort_devices(devices_info, nr_devices); |
| |
| i = nr_devices - 1; |
| avail_space = 0; |
| while (nr_devices >= min_stripes) { |
| if (num_stripes > nr_devices) |
| num_stripes = nr_devices; |
| |
| if (devices_info[i].max_avail >= min_stripe_size) { |
| int j; |
| u64 alloc_size; |
| |
| avail_space += devices_info[i].max_avail * num_stripes; |
| alloc_size = devices_info[i].max_avail; |
| for (j = i + 1 - num_stripes; j <= i; j++) |
| devices_info[j].max_avail -= alloc_size; |
| } |
| i--; |
| nr_devices--; |
| } |
| |
| kfree(devices_info); |
| *free_bytes = avail_space; |
| return 0; |
| } |
| |
| /* |
| * Calculate numbers for 'df', pessimistic in case of mixed raid profiles. |
| * |
| * If there's a redundant raid level at DATA block groups, use the respective |
| * multiplier to scale the sizes. |
| * |
| * Unused device space usage is based on simulating the chunk allocator |
| * algorithm that respects the device sizes, order of allocations and the |
| * 'alloc_start' value, this is a close approximation of the actual use but |
| * there are other factors that may change the result (like a new metadata |
| * chunk). |
| * |
| * If metadata is exhausted, f_bavail will be 0. |
| * |
| * FIXME: not accurate for mixed block groups, total and free/used are ok, |
| * available appears slightly larger. |
| */ |
| static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
| { |
| struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb); |
| struct btrfs_super_block *disk_super = fs_info->super_copy; |
| struct list_head *head = &fs_info->space_info; |
| struct btrfs_space_info *found; |
| u64 total_used = 0; |
| u64 total_free_data = 0; |
| u64 total_free_meta = 0; |
| int bits = dentry->d_sb->s_blocksize_bits; |
| __be32 *fsid = (__be32 *)fs_info->fsid; |
| unsigned factor = 1; |
| struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; |
| int ret; |
| u64 thresh = 0; |
| int mixed = 0; |
| |
| /* |
| * holding chunk_mutex to avoid allocating new chunks, holding |
| * device_list_mutex to avoid the device being removed |
| */ |
| rcu_read_lock(); |
| list_for_each_entry_rcu(found, head, list) { |
| if (found->flags & BTRFS_BLOCK_GROUP_DATA) { |
| int i; |
| |
| total_free_data += found->disk_total - found->disk_used; |
| total_free_data -= |
| btrfs_account_ro_block_groups_free_space(found); |
| |
| for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { |
| if (!list_empty(&found->block_groups[i])) { |
| switch (i) { |
| case BTRFS_RAID_DUP: |
| case BTRFS_RAID_RAID1: |
| case BTRFS_RAID_RAID10: |
| factor = 2; |
| } |
| } |
| } |
| } |
| |
| /* |
| * Metadata in mixed block goup profiles are accounted in data |
| */ |
| if (!mixed && found->flags & BTRFS_BLOCK_GROUP_METADATA) { |
| if (found->flags & BTRFS_BLOCK_GROUP_DATA) |
| mixed = 1; |
| else |
| total_free_meta += found->disk_total - |
| found->disk_used; |
| } |
| |
| total_used += found->disk_used; |
| } |
| |
| rcu_read_unlock(); |
| |
| buf->f_blocks = div_u64(btrfs_super_total_bytes(disk_super), factor); |
| buf->f_blocks >>= bits; |
| buf->f_bfree = buf->f_blocks - (div_u64(total_used, factor) >> bits); |
| |
| /* Account global block reserve as used, it's in logical size already */ |
| spin_lock(&block_rsv->lock); |
| /* Mixed block groups accounting is not byte-accurate, avoid overflow */ |
| if (buf->f_bfree >= block_rsv->size >> bits) |
| buf->f_bfree -= block_rsv->size >> bits; |
| else |
| buf->f_bfree = 0; |
| spin_unlock(&block_rsv->lock); |
| |
| buf->f_bavail = div_u64(total_free_data, factor); |
| ret = btrfs_calc_avail_data_space(fs_info->tree_root, &total_free_data); |
| if (ret) |
| return ret; |
| buf->f_bavail += div_u64(total_free_data, factor); |
| buf->f_bavail = buf->f_bavail >> bits; |
| |
| /* |
| * We calculate the remaining metadata space minus global reserve. If |
| * this is (supposedly) smaller than zero, there's no space. But this |
| * does not hold in practice, the exhausted state happens where's still |
| * some positive delta. So we apply some guesswork and compare the |
| * delta to a 4M threshold. (Practically observed delta was ~2M.) |
| * |
| * We probably cannot calculate the exact threshold value because this |
| * depends on the internal reservations requested by various |
| * operations, so some operations that consume a few metadata will |
| * succeed even if the Avail is zero. But this is better than the other |
| * way around. |
| */ |
| thresh = 4 * 1024 * 1024; |
| |
| if (!mixed && total_free_meta - thresh < block_rsv->size) |
| buf->f_bavail = 0; |
| |
| buf->f_type = BTRFS_SUPER_MAGIC; |
| buf->f_bsize = dentry->d_sb->s_blocksize; |
| buf->f_namelen = BTRFS_NAME_LEN; |
| |
| /* We treat it as constant endianness (it doesn't matter _which_) |
| because we want the fsid to come out the same whether mounted |
| on a big-endian or little-endian host */ |
| buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); |
| buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); |
| /* Mask in the root object ID too, to disambiguate subvols */ |
| buf->f_fsid.val[0] ^= BTRFS_I(d_inode(dentry))->root->objectid >> 32; |
| buf->f_fsid.val[1] ^= BTRFS_I(d_inode(dentry))->root->objectid; |
| |
| return 0; |
| } |
| |
| static void btrfs_kill_super(struct super_block *sb) |
| { |
| struct btrfs_fs_info *fs_info = btrfs_sb(sb); |
| kill_anon_super(sb); |
| free_fs_info(fs_info); |
| } |
| |
| static struct file_system_type btrfs_fs_type = { |
| .owner = THIS_MODULE, |
| .name = "btrfs", |
| .mount = btrfs_mount, |
| .kill_sb = btrfs_kill_super, |
| .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA, |
| }; |
| MODULE_ALIAS_FS("btrfs"); |
| |
| static int btrfs_control_open(struct inode *inode, struct file *file) |
| { |
| /* |
| * The control file's private_data is used to hold the |
| * transaction when it is started and is used to keep |
| * track of whether a transaction is already in progress. |
| */ |
| file->private_data = NULL; |
| return 0; |
| } |
| |
| /* |
| * used by btrfsctl to scan devices when no FS is mounted |
| */ |
| static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| struct btrfs_ioctl_vol_args *vol; |
| struct btrfs_fs_devices *fs_devices; |
| int ret = -ENOTTY; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| vol = memdup_user((void __user *)arg, sizeof(*vol)); |
| if (IS_ERR(vol)) |
| return PTR_ERR(vol); |
| |
| switch (cmd) { |
| case BTRFS_IOC_SCAN_DEV: |
| ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
| &btrfs_fs_type, &fs_devices); |
| break; |
| case BTRFS_IOC_DEVICES_READY: |
| ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
| &btrfs_fs_type, &fs_devices); |
| if (ret) |
| break; |
| ret = !(fs_devices->num_devices == fs_devices->total_devices); |
| break; |
| case BTRFS_IOC_GET_SUPPORTED_FEATURES: |
| ret = btrfs_ioctl_get_supported_features((void __user*)arg); |
| break; |
| } |
| |
| kfree(vol); |
| return ret; |
| } |
| |
| static int btrfs_freeze(struct super_block *sb) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = btrfs_sb(sb)->tree_root; |
| |
| trans = btrfs_attach_transaction_barrier(root); |
| if (IS_ERR(trans)) { |
| /* no transaction, don't bother */ |
| if (PTR_ERR(trans) == -ENOENT) |
| return 0; |
| return PTR_ERR(trans); |
| } |
| return btrfs_commit_transaction(trans, root); |
| } |
| |
| static int btrfs_show_devname(struct seq_file *m, struct dentry *root) |
| { |
| struct btrfs_fs_info *fs_info = btrfs_sb(root->d_sb); |
| struct btrfs_fs_devices *cur_devices; |
| struct btrfs_device *dev, *first_dev = NULL; |
| struct list_head *head; |
| struct rcu_string *name; |
| |
| mutex_lock(&fs_info->fs_devices->device_list_mutex); |
| cur_devices = fs_info->fs_devices; |
| while (cur_devices) { |
| head = &cur_devices->devices; |
| list_for_each_entry(dev, head, dev_list) { |
| if (dev->missing) |
| continue; |
| if (!dev->name) |
| continue; |
| if (!first_dev || dev->devid < first_dev->devid) |
| first_dev = dev; |
| } |
| cur_devices = cur_devices->seed; |
| } |
| |
| if (first_dev) { |
| rcu_read_lock(); |
| name = rcu_dereference(first_dev->name); |
| seq_escape(m, name->str, " \t\n\\"); |
| rcu_read_unlock(); |
| } else { |
| WARN_ON(1); |
| } |
| mutex_unlock(&fs_info->fs_devices->device_list_mutex); |
| return 0; |
| } |
| |
| static const struct super_operations btrfs_super_ops = { |
| .drop_inode = btrfs_drop_inode, |
| .evict_inode = btrfs_evict_inode, |
| .put_super = btrfs_put_super, |
| .sync_fs = btrfs_sync_fs, |
| .show_options = btrfs_show_options, |
| .show_devname = btrfs_show_devname, |
| .write_inode = btrfs_write_inode, |
| .alloc_inode = btrfs_alloc_inode, |
| .destroy_inode = btrfs_destroy_inode, |
| .statfs = btrfs_statfs, |
| .remount_fs = btrfs_remount, |
| .freeze_fs = btrfs_freeze, |
| }; |
| |
| static const struct file_operations btrfs_ctl_fops = { |
| .open = btrfs_control_open, |
| .unlocked_ioctl = btrfs_control_ioctl, |
| .compat_ioctl = btrfs_control_ioctl, |
| .owner = THIS_MODULE, |
| .llseek = noop_llseek, |
| }; |
| |
| static struct miscdevice btrfs_misc = { |
| .minor = BTRFS_MINOR, |
| .name = "btrfs-control", |
| .fops = &btrfs_ctl_fops |
| }; |
| |
| MODULE_ALIAS_MISCDEV(BTRFS_MINOR); |
| MODULE_ALIAS("devname:btrfs-control"); |
| |
| static int btrfs_interface_init(void) |
| { |
| return misc_register(&btrfs_misc); |
| } |
| |
| static void btrfs_interface_exit(void) |
| { |
| misc_deregister(&btrfs_misc); |
| } |
| |
| static void btrfs_print_mod_info(void) |
| { |
| printk(KERN_INFO "Btrfs loaded, crc32c=%s" |
| #ifdef CONFIG_BTRFS_DEBUG |
| ", debug=on" |
| #endif |
| #ifdef CONFIG_BTRFS_ASSERT |
| ", assert=on" |
| #endif |
| #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY |
| ", integrity-checker=on" |
| #endif |
| "\n", |
| btrfs_crc32c_impl()); |
| } |
| |
| static int btrfs_run_sanity_tests(void) |
| { |
| int ret, i; |
| u32 sectorsize, nodesize; |
| u32 test_sectorsize[] = { |
| PAGE_SIZE, |
| }; |
| ret = btrfs_init_test_fs(); |
| if (ret) |
| return ret; |
| for (i = 0; i < ARRAY_SIZE(test_sectorsize); i++) { |
| sectorsize = test_sectorsize[i]; |
| for (nodesize = sectorsize; |
| nodesize <= BTRFS_MAX_METADATA_BLOCKSIZE; |
| nodesize <<= 1) { |
| pr_info("BTRFS: selftest: sectorsize: %u nodesize: %u\n", |
| sectorsize, nodesize); |
| ret = btrfs_test_free_space_cache(sectorsize, nodesize); |
| if (ret) |
| goto out; |
| ret = btrfs_test_extent_buffer_operations(sectorsize, |
| nodesize); |
| if (ret) |
| goto out; |
| ret = btrfs_test_extent_io(sectorsize, nodesize); |
| if (ret) |
| goto out; |
| ret = btrfs_test_inodes(sectorsize, nodesize); |
| if (ret) |
| goto out; |
| ret = btrfs_test_qgroups(sectorsize, nodesize); |
| if (ret) |
| goto out; |
| ret = btrfs_test_free_space_tree(sectorsize, nodesize); |
| if (ret) |
| goto out; |
| } |
| } |
| out: |
| btrfs_destroy_test_fs(); |
| return ret; |
| } |
| |
| static int __init init_btrfs_fs(void) |
| { |
| int err; |
| |
| err = btrfs_hash_init(); |
| if (err) |
| return err; |
| |
| btrfs_props_init(); |
| |
| err = btrfs_init_sysfs(); |
| if (err) |
| goto free_hash; |
| |
| btrfs_init_compress(); |
| |
| err = btrfs_init_cachep(); |
| if (err) |
| goto free_compress; |
| |
| err = extent_io_init(); |
| if (err) |
| goto free_cachep; |
| |
| err = extent_map_init(); |
| if (err) |
| goto free_extent_io; |
| |
| err = ordered_data_init(); |
| if (err) |
| goto free_extent_map; |
| |
| err = btrfs_delayed_inode_init(); |
| if (err) |
| goto free_ordered_data; |
| |
| err = btrfs_auto_defrag_init(); |
| if (err) |
| goto free_delayed_inode; |
| |
| err = btrfs_delayed_ref_init(); |
| if (err) |
| goto free_auto_defrag; |
| |
| err = btrfs_prelim_ref_init(); |
| if (err) |
| goto free_delayed_ref; |
| |
| err = btrfs_end_io_wq_init(); |
| if (err) |
| goto free_prelim_ref; |
| |
| err = btrfs_interface_init(); |
| if (err) |
| goto free_end_io_wq; |
| |
| btrfs_init_lockdep(); |
| |
| btrfs_print_mod_info(); |
| |
| err = btrfs_run_sanity_tests(); |
| if (err) |
| goto unregister_ioctl; |
| |
| err = register_filesystem(&btrfs_fs_type); |
| if (err) |
| goto unregister_ioctl; |
| |
| return 0; |
| |
| unregister_ioctl: |
| btrfs_interface_exit(); |
| free_end_io_wq: |
| btrfs_end_io_wq_exit(); |
| free_prelim_ref: |
| btrfs_prelim_ref_exit(); |
| free_delayed_ref: |
| btrfs_delayed_ref_exit(); |
| free_auto_defrag: |
| btrfs_auto_defrag_exit(); |
| free_delayed_inode: |
| btrfs_delayed_inode_exit(); |
| free_ordered_data: |
| ordered_data_exit(); |
| free_extent_map: |
| extent_map_exit(); |
| free_extent_io: |
| extent_io_exit(); |
| free_cachep: |
| btrfs_destroy_cachep(); |
| free_compress: |
| btrfs_exit_compress(); |
| btrfs_exit_sysfs(); |
| free_hash: |
| btrfs_hash_exit(); |
| return err; |
| } |
| |
| static void __exit exit_btrfs_fs(void) |
| { |
| btrfs_destroy_cachep(); |
| btrfs_delayed_ref_exit(); |
| btrfs_auto_defrag_exit(); |
| btrfs_delayed_inode_exit(); |
| btrfs_prelim_ref_exit(); |
| ordered_data_exit(); |
| extent_map_exit(); |
| extent_io_exit(); |
| btrfs_interface_exit(); |
| btrfs_end_io_wq_exit(); |
| unregister_filesystem(&btrfs_fs_type); |
| btrfs_exit_sysfs(); |
| btrfs_cleanup_fs_uuids(); |
| btrfs_exit_compress(); |
| btrfs_hash_exit(); |
| } |
| |
| late_initcall(init_btrfs_fs); |
| module_exit(exit_btrfs_fs) |
| |
| MODULE_LICENSE("GPL"); |