diff options
Diffstat (limited to 'fs/btrfs/super.c')
| -rw-r--r-- | fs/btrfs/super.c | 2301 |
1 files changed, 1178 insertions, 1123 deletions
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index ef256b944c..c45fdaf24c 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -27,6 +27,7 @@ #include <linux/crc32c.h> #include <linux/btrfs.h> #include <linux/security.h> +#include <linux/fs_parser.h> #include "messages.h" #include "delayed-inode.h" #include "ctree.h" @@ -64,19 +65,7 @@ #include <trace/events/btrfs.h> static const struct super_operations btrfs_super_ops; - -/* - * Types for mounting the default subvolume and a subvolume explicitly - * requested by subvol=/path. That way the callchain is straightforward and we - * don't have to play tricks with the mount options and recursive calls to - * btrfs_mount. - * - * The new btrfs_root_fs_type also servers as a tag for the bdev_holder. - */ static struct file_system_type btrfs_fs_type; -static struct file_system_type btrfs_root_fs_type; - -static int btrfs_remount(struct super_block *sb, int *flags, char *data); static void btrfs_put_super(struct super_block *sb) { @@ -86,8 +75,22 @@ static void btrfs_put_super(struct super_block *sb) close_ctree(fs_info); } +/* Store the mount options related information. */ +struct btrfs_fs_context { + char *subvol_name; + u64 subvol_objectid; + u64 max_inline; + u32 commit_interval; + u32 metadata_ratio; + u32 thread_pool_size; + unsigned long mount_opt; + unsigned long compress_type:4; + unsigned int compress_level; + refcount_t refs; +}; + enum { - Opt_acl, Opt_noacl, + Opt_acl, Opt_clear_cache, Opt_commit_interval, Opt_compress, @@ -97,27 +100,26 @@ enum { Opt_degraded, Opt_device, Opt_fatal_errors, - Opt_flushoncommit, Opt_noflushoncommit, + Opt_flushoncommit, Opt_max_inline, - Opt_barrier, Opt_nobarrier, - Opt_datacow, Opt_nodatacow, - Opt_datasum, Opt_nodatasum, - Opt_defrag, Opt_nodefrag, - Opt_discard, Opt_nodiscard, + Opt_barrier, + Opt_datacow, + Opt_datasum, + Opt_defrag, + Opt_discard, Opt_discard_mode, - Opt_norecovery, Opt_ratio, Opt_rescan_uuid_tree, Opt_skip_balance, - Opt_space_cache, Opt_no_space_cache, + Opt_space_cache, Opt_space_cache_version, - Opt_ssd, Opt_nossd, - Opt_ssd_spread, Opt_nossd_spread, + Opt_ssd, + Opt_ssd_spread, Opt_subvol, Opt_subvol_empty, Opt_subvolid, Opt_thread_pool, - Opt_treelog, Opt_notreelog, + Opt_treelog, Opt_user_subvol_rm_allowed, /* Rescue options */ @@ -128,14 +130,10 @@ enum { Opt_ignoredatacsums, Opt_rescue_all, - /* Deprecated options */ - Opt_recovery, - Opt_inode_cache, Opt_noinode_cache, - /* Debugging options */ - Opt_enospc_debug, Opt_noenospc_debug, + Opt_enospc_debug, #ifdef CONFIG_BTRFS_DEBUG - Opt_fragment_data, Opt_fragment_metadata, Opt_fragment_all, + Opt_fragment, Opt_fragment_data, Opt_fragment_metadata, Opt_fragment_all, #endif #ifdef CONFIG_BTRFS_FS_REF_VERIFY Opt_ref_verify, @@ -143,785 +141,611 @@ enum { Opt_err, }; -static const match_table_t tokens = { - {Opt_acl, "acl"}, - {Opt_noacl, "noacl"}, - {Opt_clear_cache, "clear_cache"}, - {Opt_commit_interval, "commit=%u"}, - {Opt_compress, "compress"}, - {Opt_compress_type, "compress=%s"}, - {Opt_compress_force, "compress-force"}, - {Opt_compress_force_type, "compress-force=%s"}, - {Opt_degraded, "degraded"}, - {Opt_device, "device=%s"}, - {Opt_fatal_errors, "fatal_errors=%s"}, - {Opt_flushoncommit, "flushoncommit"}, - {Opt_noflushoncommit, "noflushoncommit"}, - {Opt_inode_cache, "inode_cache"}, - {Opt_noinode_cache, "noinode_cache"}, - {Opt_max_inline, "max_inline=%s"}, - {Opt_barrier, "barrier"}, - {Opt_nobarrier, "nobarrier"}, - {Opt_datacow, "datacow"}, - {Opt_nodatacow, "nodatacow"}, - {Opt_datasum, "datasum"}, - {Opt_nodatasum, "nodatasum"}, - {Opt_defrag, "autodefrag"}, - {Opt_nodefrag, "noautodefrag"}, - {Opt_discard, "discard"}, - {Opt_discard_mode, "discard=%s"}, - {Opt_nodiscard, "nodiscard"}, - {Opt_norecovery, "norecovery"}, - {Opt_ratio, "metadata_ratio=%u"}, - {Opt_rescan_uuid_tree, "rescan_uuid_tree"}, - {Opt_skip_balance, "skip_balance"}, - {Opt_space_cache, "space_cache"}, - {Opt_no_space_cache, "nospace_cache"}, - {Opt_space_cache_version, "space_cache=%s"}, - {Opt_ssd, "ssd"}, - {Opt_nossd, "nossd"}, - {Opt_ssd_spread, "ssd_spread"}, - {Opt_nossd_spread, "nossd_spread"}, - {Opt_subvol, "subvol=%s"}, - {Opt_subvol_empty, "subvol="}, - {Opt_subvolid, "subvolid=%s"}, - {Opt_thread_pool, "thread_pool=%u"}, - {Opt_treelog, "treelog"}, - {Opt_notreelog, "notreelog"}, - {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, +enum { + Opt_fatal_errors_panic, + Opt_fatal_errors_bug, +}; - /* Rescue options */ - {Opt_rescue, "rescue=%s"}, +static const struct constant_table btrfs_parameter_fatal_errors[] = { + { "panic", Opt_fatal_errors_panic }, + { "bug", Opt_fatal_errors_bug }, + {} +}; + +enum { + Opt_discard_sync, + Opt_discard_async, +}; + +static const struct constant_table btrfs_parameter_discard[] = { + { "sync", Opt_discard_sync }, + { "async", Opt_discard_async }, + {} +}; + +enum { + Opt_space_cache_v1, + Opt_space_cache_v2, +}; + +static const struct constant_table btrfs_parameter_space_cache[] = { + { "v1", Opt_space_cache_v1 }, + { "v2", Opt_space_cache_v2 }, + {} +}; + +enum { + Opt_rescue_usebackuproot, + Opt_rescue_nologreplay, + Opt_rescue_ignorebadroots, + Opt_rescue_ignoredatacsums, + Opt_rescue_parameter_all, +}; + +static const struct constant_table btrfs_parameter_rescue[] = { + { "usebackuproot", Opt_rescue_usebackuproot }, + { "nologreplay", Opt_rescue_nologreplay }, + { "ignorebadroots", Opt_rescue_ignorebadroots }, + { "ibadroots", Opt_rescue_ignorebadroots }, + { "ignoredatacsums", Opt_rescue_ignoredatacsums }, + { "idatacsums", Opt_rescue_ignoredatacsums }, + { "all", Opt_rescue_parameter_all }, + {} +}; + +#ifdef CONFIG_BTRFS_DEBUG +enum { + Opt_fragment_parameter_data, + Opt_fragment_parameter_metadata, + Opt_fragment_parameter_all, +}; + +static const struct constant_table btrfs_parameter_fragment[] = { + { "data", Opt_fragment_parameter_data }, + { "metadata", Opt_fragment_parameter_metadata }, + { "all", Opt_fragment_parameter_all }, + {} +}; +#endif + +static const struct fs_parameter_spec btrfs_fs_parameters[] = { + fsparam_flag_no("acl", Opt_acl), + fsparam_flag_no("autodefrag", Opt_defrag), + fsparam_flag_no("barrier", Opt_barrier), + fsparam_flag("clear_cache", Opt_clear_cache), + fsparam_u32("commit", Opt_commit_interval), + fsparam_flag("compress", Opt_compress), + fsparam_string("compress", Opt_compress_type), + fsparam_flag("compress-force", Opt_compress_force), + fsparam_string("compress-force", Opt_compress_force_type), + fsparam_flag_no("datacow", Opt_datacow), + fsparam_flag_no("datasum", Opt_datasum), + fsparam_flag("degraded", Opt_degraded), + fsparam_string("device", Opt_device), + fsparam_flag_no("discard", Opt_discard), + fsparam_enum("discard", Opt_discard_mode, btrfs_parameter_discard), + fsparam_enum("fatal_errors", Opt_fatal_errors, btrfs_parameter_fatal_errors), + fsparam_flag_no("flushoncommit", Opt_flushoncommit), + fsparam_string("max_inline", Opt_max_inline), + fsparam_u32("metadata_ratio", Opt_ratio), + fsparam_flag("rescan_uuid_tree", Opt_rescan_uuid_tree), + fsparam_flag("skip_balance", Opt_skip_balance), + fsparam_flag_no("space_cache", Opt_space_cache), + fsparam_enum("space_cache", Opt_space_cache_version, btrfs_parameter_space_cache), + fsparam_flag_no("ssd", Opt_ssd), + fsparam_flag_no("ssd_spread", Opt_ssd_spread), + fsparam_string("subvol", Opt_subvol), + fsparam_flag("subvol=", Opt_subvol_empty), + fsparam_u64("subvolid", Opt_subvolid), + fsparam_u32("thread_pool", Opt_thread_pool), + fsparam_flag_no("treelog", Opt_treelog), + fsparam_flag("user_subvol_rm_allowed", Opt_user_subvol_rm_allowed), + + /* Rescue options. */ + fsparam_enum("rescue", Opt_rescue, btrfs_parameter_rescue), /* Deprecated, with alias rescue=nologreplay */ - {Opt_nologreplay, "nologreplay"}, + __fsparam(NULL, "nologreplay", Opt_nologreplay, fs_param_deprecated, NULL), /* Deprecated, with alias rescue=usebackuproot */ - {Opt_usebackuproot, "usebackuproot"}, + __fsparam(NULL, "usebackuproot", Opt_usebackuproot, fs_param_deprecated, NULL), - /* Deprecated options */ - {Opt_recovery, "recovery"}, - - /* Debugging options */ - {Opt_enospc_debug, "enospc_debug"}, - {Opt_noenospc_debug, "noenospc_debug"}, + /* Debugging options. */ + fsparam_flag_no("enospc_debug", Opt_enospc_debug), #ifdef CONFIG_BTRFS_DEBUG - {Opt_fragment_data, "fragment=data"}, - {Opt_fragment_metadata, "fragment=metadata"}, - {Opt_fragment_all, "fragment=all"}, + fsparam_enum("fragment", Opt_fragment, btrfs_parameter_fragment), #endif #ifdef CONFIG_BTRFS_FS_REF_VERIFY - {Opt_ref_verify, "ref_verify"}, + fsparam_flag("ref_verify", Opt_ref_verify), #endif - {Opt_err, NULL}, + {} }; -static const match_table_t rescue_tokens = { - {Opt_usebackuproot, "usebackuproot"}, - {Opt_nologreplay, "nologreplay"}, - {Opt_ignorebadroots, "ignorebadroots"}, - {Opt_ignorebadroots, "ibadroots"}, - {Opt_ignoredatacsums, "ignoredatacsums"}, - {Opt_ignoredatacsums, "idatacsums"}, - {Opt_rescue_all, "all"}, - {Opt_err, NULL}, -}; - -static bool check_ro_option(struct btrfs_fs_info *fs_info, unsigned long opt, - const char *opt_name) +/* No support for restricting writes to btrfs devices yet... */ +static inline blk_mode_t btrfs_open_mode(struct fs_context *fc) { - if (fs_info->mount_opt & opt) { - btrfs_err(fs_info, "%s must be used with ro mount option", - opt_name); - return true; - } - return false; + return sb_open_mode(fc->sb_flags) & ~BLK_OPEN_RESTRICT_WRITES; } -static int parse_rescue_options(struct btrfs_fs_info *info, const char *options) +static int btrfs_parse_param(struct fs_context *fc, struct fs_parameter *param) { - char *opts; - char *orig; - char *p; - substring_t args[MAX_OPT_ARGS]; - int ret = 0; + struct btrfs_fs_context *ctx = fc->fs_private; + struct fs_parse_result result; + int opt; - opts = kstrdup(options, GFP_KERNEL); - if (!opts) - return -ENOMEM; - orig = opts; + opt = fs_parse(fc, btrfs_fs_parameters, param, &result); + if (opt < 0) + return opt; - while ((p = strsep(&opts, ":")) != NULL) { - int token; + switch (opt) { + case Opt_degraded: + btrfs_set_opt(ctx->mount_opt, DEGRADED); + break; + case Opt_subvol_empty: + /* + * This exists because we used to allow it on accident, so we're + * keeping it to maintain ABI. See 37becec95ac3 ("Btrfs: allow + * empty subvol= again"). + */ + break; + case Opt_subvol: + kfree(ctx->subvol_name); + ctx->subvol_name = kstrdup(param->string, GFP_KERNEL); + if (!ctx->subvol_name) + return -ENOMEM; + break; + case Opt_subvolid: + ctx->subvol_objectid = result.uint_64; - if (!*p) - continue; - token = match_token(p, rescue_tokens, args); - switch (token){ - case Opt_usebackuproot: - btrfs_info(info, - "trying to use backup root at mount time"); - btrfs_set_opt(info->mount_opt, USEBACKUPROOT); - break; - case Opt_nologreplay: - btrfs_set_and_info(info, NOLOGREPLAY, - "disabling log replay at mount time"); - break; - case Opt_ignorebadroots: - btrfs_set_and_info(info, IGNOREBADROOTS, - "ignoring bad roots"); - break; - case Opt_ignoredatacsums: - btrfs_set_and_info(info, IGNOREDATACSUMS, - "ignoring data csums"); - break; - case Opt_rescue_all: - btrfs_info(info, "enabling all of the rescue options"); - btrfs_set_and_info(info, IGNOREDATACSUMS, - "ignoring data csums"); - btrfs_set_and_info(info, IGNOREBADROOTS, - "ignoring bad roots"); - btrfs_set_and_info(info, NOLOGREPLAY, - "disabling log replay at mount time"); - break; - case Opt_err: - btrfs_info(info, "unrecognized rescue option '%s'", p); - ret = -EINVAL; - goto out; - default: - break; - } + /* subvolid=0 means give me the original fs_tree. */ + if (!ctx->subvol_objectid) + ctx->subvol_objectid = BTRFS_FS_TREE_OBJECTID; + break; + case Opt_device: { + struct btrfs_device *device; + blk_mode_t mode = btrfs_open_mode(fc); + mutex_lock(&uuid_mutex); + device = btrfs_scan_one_device(param->string, mode, false); + mutex_unlock(&uuid_mutex); + if (IS_ERR(device)) + return PTR_ERR(device); + break; } -out: - kfree(orig); - return ret; -} - -/* - * 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_fs_info *info, char *options, - unsigned long new_flags) -{ - substring_t args[MAX_OPT_ARGS]; - char *p, *num; - int intarg; - int ret = 0; - char *compress_type; - bool compress_force = false; - enum btrfs_compression_type saved_compress_type; - int saved_compress_level; - bool saved_compress_force; - int no_compress = 0; - const bool remounting = test_bit(BTRFS_FS_STATE_REMOUNTING, &info->fs_state); - - if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE)) - btrfs_set_opt(info->mount_opt, FREE_SPACE_TREE); - else if (btrfs_free_space_cache_v1_active(info)) { - if (btrfs_is_zoned(info)) { - btrfs_info(info, - "zoned: clearing existing space cache"); - btrfs_set_super_cache_generation(info->super_copy, 0); + case Opt_datasum: + if (result.negated) { + btrfs_set_opt(ctx->mount_opt, NODATASUM); } else { - btrfs_set_opt(info->mount_opt, SPACE_CACHE); + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); } - } - - /* - * Even the options are empty, we still need to do extra check - * against new flags - */ - if (!options) - goto check; - - while ((p = strsep(&options, ",")) != NULL) { - int token; - if (!*p) - continue; - - token = match_token(p, tokens, args); - switch (token) { - case Opt_degraded: - btrfs_info(info, "allowing degraded mounts"); - btrfs_set_opt(info->mount_opt, DEGRADED); - break; - case Opt_subvol: - case Opt_subvol_empty: - case Opt_subvolid: - case Opt_device: - /* - * These are parsed by btrfs_parse_subvol_options or - * btrfs_parse_device_options and can be ignored here. - */ - break; - case Opt_nodatasum: - btrfs_set_and_info(info, NODATASUM, - "setting nodatasum"); - break; - case Opt_datasum: - if (btrfs_test_opt(info, NODATASUM)) { - if (btrfs_test_opt(info, NODATACOW)) - btrfs_info(info, - "setting datasum, datacow enabled"); - else - btrfs_info(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(info, NODATACOW)) { - if (!btrfs_test_opt(info, COMPRESS) || - !btrfs_test_opt(info, FORCE_COMPRESS)) { - btrfs_info(info, - "setting nodatacow, compression disabled"); - } else { - btrfs_info(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(info, 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(info, - COMPRESS) ? - info->compress_type : BTRFS_COMPRESS_NONE; - saved_compress_force = - btrfs_test_opt(info, FORCE_COMPRESS); - saved_compress_level = info->compress_level; - if (token == Opt_compress || - token == Opt_compress_force || - strncmp(args[0].from, "zlib", 4) == 0) { - compress_type = "zlib"; - - info->compress_type = BTRFS_COMPRESS_ZLIB; - info->compress_level = BTRFS_ZLIB_DEFAULT_LEVEL; - /* - * args[0] contains uninitialized data since - * for these tokens we don't expect any - * parameter. - */ - if (token != Opt_compress && - token != Opt_compress_force) - info->compress_level = - btrfs_compress_str2level( - BTRFS_COMPRESS_ZLIB, - args[0].from + 4); - 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 (strncmp(args[0].from, "lzo", 3) == 0) { - compress_type = "lzo"; - info->compress_type = BTRFS_COMPRESS_LZO; - info->compress_level = 0; - 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, "zstd", 4) == 0) { - compress_type = "zstd"; - info->compress_type = BTRFS_COMPRESS_ZSTD; - info->compress_level = - btrfs_compress_str2level( - BTRFS_COMPRESS_ZSTD, - args[0].from + 4); - 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_ZSTD); - no_compress = 0; - } else if (strncmp(args[0].from, "no", 2) == 0) { - compress_type = "no"; - info->compress_level = 0; - info->compress_type = 0; - btrfs_clear_opt(info->mount_opt, COMPRESS); - btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); - compress_force = false; - no_compress++; - } else { - btrfs_err(info, "unrecognized compression value %s", - args[0].from); - 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 (no_compress == 1) { - btrfs_info(info, "use no compression"); - } else if ((info->compress_type != saved_compress_type) || - (compress_force != saved_compress_force) || - (info->compress_level != saved_compress_level)) { - btrfs_info(info, "%s %s compression, level %d", - (compress_force) ? "force" : "use", - compress_type, info->compress_level); - } - compress_force = false; - break; - case Opt_ssd: - btrfs_set_and_info(info, SSD, - "enabling ssd optimizations"); - btrfs_clear_opt(info->mount_opt, NOSSD); - break; - case Opt_ssd_spread: - btrfs_set_and_info(info, SSD, - "enabling ssd optimizations"); - btrfs_set_and_info(info, SSD_SPREAD, - "using spread ssd allocation scheme"); - btrfs_clear_opt(info->mount_opt, NOSSD); - break; - case Opt_nossd: - btrfs_set_opt(info->mount_opt, NOSSD); - btrfs_clear_and_info(info, SSD, - "not using ssd optimizations"); - fallthrough; - case Opt_nossd_spread: - btrfs_clear_and_info(info, SSD_SPREAD, - "not using spread ssd allocation scheme"); - break; - case Opt_barrier: - btrfs_clear_and_info(info, NOBARRIER, - "turning on barriers"); - break; - case Opt_nobarrier: - btrfs_set_and_info(info, NOBARRIER, - "turning off barriers"); - break; - case Opt_thread_pool: - ret = match_int(&args[0], &intarg); - if (ret) { - btrfs_err(info, "unrecognized thread_pool value %s", - args[0].from); - goto out; - } else if (intarg == 0) { - btrfs_err(info, "invalid value 0 for thread_pool"); - ret = -EINVAL; - goto out; - } - info->thread_pool_size = intarg; - 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, - info->sectorsize); - } - btrfs_info(info, "max_inline at %llu", - info->max_inline); - } else { - ret = -ENOMEM; - goto out; - } - break; - case Opt_acl: + break; + case Opt_datacow: + if (result.negated) { + btrfs_clear_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, FORCE_COMPRESS); + btrfs_set_opt(ctx->mount_opt, NODATACOW); + btrfs_set_opt(ctx->mount_opt, NODATASUM); + } else { + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + } + break; + case Opt_compress_force: + case Opt_compress_force_type: + btrfs_set_opt(ctx->mount_opt, FORCE_COMPRESS); + fallthrough; + case Opt_compress: + case Opt_compress_type: + if (opt == Opt_compress || opt == Opt_compress_force) { + ctx->compress_type = BTRFS_COMPRESS_ZLIB; + ctx->compress_level = BTRFS_ZLIB_DEFAULT_LEVEL; + btrfs_set_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); + } else if (strncmp(param->string, "zlib", 4) == 0) { + ctx->compress_type = BTRFS_COMPRESS_ZLIB; + ctx->compress_level = + btrfs_compress_str2level(BTRFS_COMPRESS_ZLIB, + param->string + 4); + btrfs_set_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); + } else if (strncmp(param->string, "lzo", 3) == 0) { + ctx->compress_type = BTRFS_COMPRESS_LZO; + ctx->compress_level = 0; + btrfs_set_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); + } else if (strncmp(param->string, "zstd", 4) == 0) { + ctx->compress_type = BTRFS_COMPRESS_ZSTD; + ctx->compress_level = + btrfs_compress_str2level(BTRFS_COMPRESS_ZSTD, + param->string + 4); + btrfs_set_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); + } else if (strncmp(param->string, "no", 2) == 0) { + ctx->compress_level = 0; + ctx->compress_type = 0; + btrfs_clear_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, FORCE_COMPRESS); + } else { + btrfs_err(NULL, "unrecognized compression value %s", + param->string); + return -EINVAL; + } + break; + case Opt_ssd: + if (result.negated) { + btrfs_set_opt(ctx->mount_opt, NOSSD); + btrfs_clear_opt(ctx->mount_opt, SSD); + btrfs_clear_opt(ctx->mount_opt, SSD_SPREAD); + } else { + btrfs_set_opt(ctx->mount_opt, SSD); + btrfs_clear_opt(ctx->mount_opt, NOSSD); + } + break; + case Opt_ssd_spread: + if (result.negated) { + btrfs_clear_opt(ctx->mount_opt, SSD_SPREAD); + } else { + btrfs_set_opt(ctx->mount_opt, SSD); + btrfs_set_opt(ctx->mount_opt, SSD_SPREAD); + btrfs_clear_opt(ctx->mount_opt, NOSSD); + } + break; + case Opt_barrier: + if (result.negated) + btrfs_set_opt(ctx->mount_opt, NOBARRIER); + else + btrfs_clear_opt(ctx->mount_opt, NOBARRIER); + break; + case Opt_thread_pool: + if (result.uint_32 == 0) { + btrfs_err(NULL, "invalid value 0 for thread_pool"); + return -EINVAL; + } + ctx->thread_pool_size = result.uint_32; + break; + case Opt_max_inline: + ctx->max_inline = memparse(param->string, NULL); + break; + case Opt_acl: + if (result.negated) { + fc->sb_flags &= ~SB_POSIXACL; + } else { #ifdef CONFIG_BTRFS_FS_POSIX_ACL - info->sb->s_flags |= SB_POSIXACL; - break; + fc->sb_flags |= SB_POSIXACL; #else - btrfs_err(info, "support for ACL not compiled in!"); - ret = -EINVAL; - goto out; + btrfs_err(NULL, "support for ACL not compiled in"); + return -EINVAL; #endif - case Opt_noacl: - info->sb->s_flags &= ~SB_POSIXACL; - break; - case Opt_notreelog: - btrfs_set_and_info(info, NOTREELOG, - "disabling tree log"); - break; - case Opt_treelog: - btrfs_clear_and_info(info, NOTREELOG, - "enabling tree log"); - break; - case Opt_norecovery: - case Opt_nologreplay: - btrfs_warn(info, + } + /* + * VFS limits the ability to toggle ACL on and off via remount, + * despite every file system allowing this. This seems to be + * an oversight since we all do, but it'll fail if we're + * remounting. So don't set the mask here, we'll check it in + * btrfs_reconfigure and do the toggling ourselves. + */ + if (fc->purpose != FS_CONTEXT_FOR_RECONFIGURE) + fc->sb_flags_mask |= SB_POSIXACL; + break; + case Opt_treelog: + if (result.negated) + btrfs_set_opt(ctx->mount_opt, NOTREELOG); + else + btrfs_clear_opt(ctx->mount_opt, NOTREELOG); + break; + case Opt_nologreplay: + btrfs_warn(NULL, "'nologreplay' is deprecated, use 'rescue=nologreplay' instead"); - btrfs_set_and_info(info, NOLOGREPLAY, - "disabling log replay at mount time"); - break; - case Opt_flushoncommit: - btrfs_set_and_info(info, FLUSHONCOMMIT, - "turning on flush-on-commit"); - break; - case Opt_noflushoncommit: - btrfs_clear_and_info(info, FLUSHONCOMMIT, - "turning off flush-on-commit"); - break; - case Opt_ratio: - ret = match_int(&args[0], &intarg); - if (ret) { - btrfs_err(info, "unrecognized metadata_ratio value %s", - args[0].from); - goto out; - } - info->metadata_ratio = intarg; - btrfs_info(info, "metadata ratio %u", - info->metadata_ratio); - break; - case Opt_discard: - case Opt_discard_mode: - if (token == Opt_discard || - strcmp(args[0].from, "sync") == 0) { - btrfs_clear_opt(info->mount_opt, DISCARD_ASYNC); - btrfs_set_and_info(info, DISCARD_SYNC, - "turning on sync discard"); - } else if (strcmp(args[0].from, "async") == 0) { - btrfs_clear_opt(info->mount_opt, DISCARD_SYNC); - btrfs_set_and_info(info, DISCARD_ASYNC, - "turning on async discard"); - } else { - btrfs_err(info, "unrecognized discard mode value %s", - args[0].from); - ret = -EINVAL; - goto out; - } - btrfs_clear_opt(info->mount_opt, NODISCARD); - break; - case Opt_nodiscard: - btrfs_clear_and_info(info, DISCARD_SYNC, - "turning off discard"); - btrfs_clear_and_info(info, DISCARD_ASYNC, - "turning off async discard"); - btrfs_set_opt(info->mount_opt, NODISCARD); - break; - case Opt_space_cache: - case Opt_space_cache_version: - /* - * We already set FREE_SPACE_TREE above because we have - * compat_ro(FREE_SPACE_TREE) set, and we aren't going - * to allow v1 to be set for extent tree v2, simply - * ignore this setting if we're extent tree v2. - */ - if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) - break; - if (token == Opt_space_cache || - strcmp(args[0].from, "v1") == 0) { - btrfs_clear_opt(info->mount_opt, - FREE_SPACE_TREE); - btrfs_set_and_info(info, SPACE_CACHE, - "enabling disk space caching"); - } else if (strcmp(args[0].from, "v2") == 0) { - btrfs_clear_opt(info->mount_opt, - SPACE_CACHE); - btrfs_set_and_info(info, FREE_SPACE_TREE, - "enabling free space tree"); - } else { - btrfs_err(info, "unrecognized space_cache value %s", - args[0].from); - 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: - /* - * We cannot operate without the free space tree with - * extent tree v2, ignore this option. - */ - if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) - break; - if (btrfs_test_opt(info, SPACE_CACHE)) { - btrfs_clear_and_info(info, SPACE_CACHE, - "disabling disk space caching"); - } - if (btrfs_test_opt(info, FREE_SPACE_TREE)) { - btrfs_clear_and_info(info, FREE_SPACE_TREE, - "disabling free space tree"); - } - break; - case Opt_inode_cache: - case Opt_noinode_cache: - btrfs_warn(info, - "the 'inode_cache' option is deprecated and has no effect since 5.11"); - break; - case Opt_clear_cache: - /* - * We cannot clear the free space tree with extent tree - * v2, ignore this option. - */ - if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) - break; - btrfs_set_and_info(info, CLEAR_CACHE, - "force clearing of disk cache"); + btrfs_set_opt(ctx->mount_opt, NOLOGREPLAY); + break; + case Opt_flushoncommit: + if (result.negated) + btrfs_clear_opt(ctx->mount_opt, FLUSHONCOMMIT); + else + btrfs_set_opt(ctx->mount_opt, FLUSHONCOMMIT); + break; + case Opt_ratio: + ctx->metadata_ratio = result.uint_32; + break; + case Opt_discard: + if (result.negated) { + btrfs_clear_opt(ctx->mount_opt, DISCARD_SYNC); + btrfs_clear_opt(ctx->mount_opt, DISCARD_ASYNC); + btrfs_set_opt(ctx->mount_opt, NODISCARD); + } else { + btrfs_set_opt(ctx->mount_opt, DISCARD_SYNC); + btrfs_clear_opt(ctx->mount_opt, DISCARD_ASYNC); + } + break; + case Opt_discard_mode: + switch (result.uint_32) { + case Opt_discard_sync: + btrfs_clear_opt(ctx->mount_opt, DISCARD_ASYNC); + btrfs_set_opt(ctx->mount_opt, DISCARD_SYNC); break; - case Opt_user_subvol_rm_allowed: - btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); + case Opt_discard_async: + btrfs_clear_opt(ctx->mount_opt, DISCARD_SYNC); + btrfs_set_opt(ctx->mount_opt, DISCARD_ASYNC); break; - case Opt_enospc_debug: - btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG); + default: + btrfs_err(NULL, "unrecognized discard mode value %s", + param->key); + return -EINVAL; + } + btrfs_clear_opt(ctx->mount_opt, NODISCARD); + break; + case Opt_space_cache: + if (result.negated) { + btrfs_set_opt(ctx->mount_opt, NOSPACECACHE); + btrfs_clear_opt(ctx->mount_opt, SPACE_CACHE); + btrfs_clear_opt(ctx->mount_opt, FREE_SPACE_TREE); + } else { + btrfs_clear_opt(ctx->mount_opt, FREE_SPACE_TREE); + btrfs_set_opt(ctx->mount_opt, SPACE_CACHE); + } + break; + case Opt_space_cache_version: + switch (result.uint_32) { + case Opt_space_cache_v1: + btrfs_set_opt(ctx->mount_opt, SPACE_CACHE); + btrfs_clear_opt(ctx->mount_opt, FREE_SPACE_TREE); break; - case Opt_noenospc_debug: - btrfs_clear_opt(info->mount_opt, ENOSPC_DEBUG); + case Opt_space_cache_v2: + btrfs_clear_opt(ctx->mount_opt, SPACE_CACHE); + btrfs_set_opt(ctx->mount_opt, FREE_SPACE_TREE); break; - case Opt_defrag: - btrfs_set_and_info(info, AUTO_DEFRAG, - "enabling auto defrag"); + default: + btrfs_err(NULL, "unrecognized space_cache value %s", + param->key); + return -EINVAL; + } + break; + case Opt_rescan_uuid_tree: + btrfs_set_opt(ctx->mount_opt, RESCAN_UUID_TREE); + break; + case Opt_clear_cache: + btrfs_set_opt(ctx->mount_opt, CLEAR_CACHE); + break; + case Opt_user_subvol_rm_allowed: + btrfs_set_opt(ctx->mount_opt, USER_SUBVOL_RM_ALLOWED); + break; + case Opt_enospc_debug: + if (result.negated) + btrfs_clear_opt(ctx->mount_opt, ENOSPC_DEBUG); + else + btrfs_set_opt(ctx->mount_opt, ENOSPC_DEBUG); + break; + case Opt_defrag: + if (result.negated) + btrfs_clear_opt(ctx->mount_opt, AUTO_DEFRAG); + else + btrfs_set_opt(ctx->mount_opt, AUTO_DEFRAG); + break; + case Opt_usebackuproot: + btrfs_warn(NULL, + "'usebackuproot' is deprecated, use 'rescue=usebackuproot' instead"); + btrfs_set_opt(ctx->mount_opt, USEBACKUPROOT); + + /* If we're loading the backup roots we can't trust the space cache. */ + btrfs_set_opt(ctx->mount_opt, CLEAR_CACHE); + break; + case Opt_skip_balance: + btrfs_set_opt(ctx->mount_opt, SKIP_BALANCE); + break; + case Opt_fatal_errors: + switch (result.uint_32) { + case Opt_fatal_errors_panic: + btrfs_set_opt(ctx->mount_opt, PANIC_ON_FATAL_ERROR); break; - case Opt_nodefrag: - btrfs_clear_and_info(info, AUTO_DEFRAG, - "disabling auto defrag"); + case Opt_fatal_errors_bug: + btrfs_clear_opt(ctx->mount_opt, PANIC_ON_FATAL_ERROR); break; - case Opt_recovery: - case Opt_usebackuproot: - btrfs_warn(info, - "'%s' is deprecated, use 'rescue=usebackuproot' instead", - token == Opt_recovery ? "recovery" : - "usebackuproot"); - btrfs_info(info, - "trying to use backup root at mount time"); - btrfs_set_opt(info->mount_opt, USEBACKUPROOT); + default: + btrfs_err(NULL, "unrecognized fatal_errors value %s", + param->key); + return -EINVAL; + } + break; + case Opt_commit_interval: + ctx->commit_interval = result.uint_32; + if (ctx->commit_interval == 0) + ctx->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL; + break; + case Opt_rescue: + switch (result.uint_32) { + case Opt_rescue_usebackuproot: + btrfs_set_opt(ctx->mount_opt, USEBACKUPROOT); break; - case Opt_skip_balance: - btrfs_set_opt(info->mount_opt, SKIP_BALANCE); + case Opt_rescue_nologreplay: + btrfs_set_opt(ctx->mount_opt, NOLOGREPLAY); break; - 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 { - btrfs_err(info, "unrecognized fatal_errors value %s", - args[0].from); - ret = -EINVAL; - goto out; - } + case Opt_rescue_ignorebadroots: + btrfs_set_opt(ctx->mount_opt, IGNOREBADROOTS); break; - case Opt_commit_interval: - intarg = 0; - ret = match_int(&args[0], &intarg); - if (ret) { - btrfs_err(info, "unrecognized commit_interval value %s", - args[0].from); - ret = -EINVAL; - goto out; - } - if (intarg == 0) { - btrfs_info(info, - "using default commit interval %us", - BTRFS_DEFAULT_COMMIT_INTERVAL); - intarg = BTRFS_DEFAULT_COMMIT_INTERVAL; - } else if (intarg > 300) { - btrfs_warn(info, "excessive commit interval %d", - intarg); - } - info->commit_interval = intarg; + case Opt_rescue_ignoredatacsums: + btrfs_set_opt(ctx->mount_opt, IGNOREDATACSUMS); break; - case Opt_rescue: - ret = parse_rescue_options(info, args[0].from); - if (ret < 0) { - btrfs_err(info, "unrecognized rescue value %s", - args[0].from); - goto out; - } + case Opt_rescue_parameter_all: + btrfs_set_opt(ctx->mount_opt, IGNOREDATACSUMS); + btrfs_set_opt(ctx->mount_opt, IGNOREBADROOTS); + btrfs_set_opt(ctx->mount_opt, NOLOGREPLAY); break; + default: + btrfs_info(NULL, "unrecognized rescue option '%s'", + param->key); + return -EINVAL; + } + break; #ifdef CONFIG_BTRFS_DEBUG - case Opt_fragment_all: - btrfs_info(info, "fragmenting all space"); - btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); - btrfs_set_opt(info->mount_opt, FRAGMENT_METADATA); + case Opt_fragment: + switch (result.uint_32) { + case Opt_fragment_parameter_all: + btrfs_set_opt(ctx->mount_opt, FRAGMENT_DATA); + btrfs_set_opt(ctx->mount_opt, FRAGMENT_METADATA); break; - case Opt_fragment_metadata: - btrfs_info(info, "fragmenting metadata"); - btrfs_set_opt(info->mount_opt, - FRAGMENT_METADATA); + case Opt_fragment_parameter_metadata: + btrfs_set_opt(ctx->mount_opt, FRAGMENT_METADATA); break; - case Opt_fragment_data: - btrfs_info(info, "fragmenting data"); - btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); + case Opt_fragment_parameter_data: + btrfs_set_opt(ctx->mount_opt, FRAGMENT_DATA); break; + default: + btrfs_info(NULL, "unrecognized fragment option '%s'", + param->key); + return -EINVAL; + } + break; #endif #ifdef CONFIG_BTRFS_FS_REF_VERIFY - case Opt_ref_verify: - btrfs_info(info, "doing ref verification"); - btrfs_set_opt(info->mount_opt, REF_VERIFY); - break; + case Opt_ref_verify: + btrfs_set_opt(ctx->mount_opt, REF_VERIFY); + break; #endif - case Opt_err: - btrfs_err(info, "unrecognized mount option '%s'", p); - ret = -EINVAL; - goto out; - default: - break; - } + default: + btrfs_err(NULL, "unrecognized mount option '%s'", param->key); + return -EINVAL; } -check: - /* We're read-only, don't have to check. */ - if (new_flags & SB_RDONLY) - goto out; - if (check_ro_option(info, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay") || - check_ro_option(info, BTRFS_MOUNT_IGNOREBADROOTS, "ignorebadroots") || - check_ro_option(info, BTRFS_MOUNT_IGNOREDATACSUMS, "ignoredatacsums")) - ret = -EINVAL; -out: - if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) && - !btrfs_test_opt(info, FREE_SPACE_TREE) && - !btrfs_test_opt(info, CLEAR_CACHE)) { - btrfs_err(info, "cannot disable free space tree"); - ret = -EINVAL; - } - if (btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE) && - !btrfs_test_opt(info, FREE_SPACE_TREE)) { - btrfs_err(info, "cannot disable free space tree with block-group-tree feature"); - ret = -EINVAL; - } - if (!ret) - ret = btrfs_check_mountopts_zoned(info); - if (!ret && !remounting) { - if (btrfs_test_opt(info, SPACE_CACHE)) - btrfs_info(info, "disk space caching is enabled"); - if (btrfs_test_opt(info, FREE_SPACE_TREE)) - btrfs_info(info, "using free space tree"); - } - return ret; + return 0; } /* - * 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. + * Some options only have meaning at mount time and shouldn't persist across + * remounts, or be displayed. Clear these at the end of mount and remount code + * paths. */ -static int btrfs_parse_device_options(const char *options, blk_mode_t flags) +static void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info) { - substring_t args[MAX_OPT_ARGS]; - char *device_name, *opts, *orig, *p; - struct btrfs_device *device = NULL; - int error = 0; + btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT); + btrfs_clear_opt(fs_info->mount_opt, CLEAR_CACHE); + btrfs_clear_opt(fs_info->mount_opt, NOSPACECACHE); +} - lockdep_assert_held(&uuid_mutex); +static bool check_ro_option(struct btrfs_fs_info *fs_info, + unsigned long mount_opt, unsigned long opt, + const char *opt_name) +{ + if (mount_opt & opt) { + btrfs_err(fs_info, "%s must be used with ro mount option", + opt_name); + return true; + } + return false; +} - if (!options) - return 0; +bool btrfs_check_options(struct btrfs_fs_info *info, unsigned long *mount_opt, + unsigned long flags) +{ + bool ret = true; - /* - * strsep changes the string, duplicate it because btrfs_parse_options - * gets called later - */ - opts = kstrdup(options, GFP_KERNEL); - if (!opts) - return -ENOMEM; - orig = opts; + if (!(flags & SB_RDONLY) && + (check_ro_option(info, *mount_opt, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay") || + check_ro_option(info, *mount_opt, BTRFS_MOUNT_IGNOREBADROOTS, "ignorebadroots") || + check_ro_option(info, *mount_opt, BTRFS_MOUNT_IGNOREDATACSUMS, "ignoredatacsums"))) + ret = false; - while ((p = strsep(&opts, ",")) != NULL) { - int token; + if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) && + !btrfs_raw_test_opt(*mount_opt, FREE_SPACE_TREE) && + !btrfs_raw_test_opt(*mount_opt, CLEAR_CACHE)) { + btrfs_err(info, "cannot disable free-space-tree"); + ret = false; + } + if (btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE) && + !btrfs_raw_test_opt(*mount_opt, FREE_SPACE_TREE)) { + btrfs_err(info, "cannot disable free-space-tree with block-group-tree feature"); + ret = false; + } - if (!*p) - continue; + if (btrfs_check_mountopts_zoned(info, mount_opt)) + ret = false; - token = match_token(p, tokens, args); - if (token == Opt_device) { - device_name = match_strdup(&args[0]); - if (!device_name) { - error = -ENOMEM; - goto out; - } - device = btrfs_scan_one_device(device_name, flags, false); - kfree(device_name); - if (IS_ERR(device)) { - error = PTR_ERR(device); - goto out; - } - } + if (!test_bit(BTRFS_FS_STATE_REMOUNTING, &info->fs_state)) { + if (btrfs_raw_test_opt(*mount_opt, SPACE_CACHE)) + btrfs_info(info, "disk space caching is enabled"); + if (btrfs_raw_test_opt(*mount_opt, FREE_SPACE_TREE)) + btrfs_info(info, "using free-space-tree"); } -out: - kfree(orig); - return error; + return ret; } /* - * Parse mount options that are related to subvolume id + * This is subtle, we only call this during open_ctree(). We need to pre-load + * the mount options with the on-disk settings. Before the new mount API took + * effect we would do this on mount and remount. With the new mount API we'll + * only do this on the initial mount. * - * The value is later passed to mount_subvol() + * This isn't a change in behavior, because we're using the current state of the + * file system to set the current mount options. If you mounted with special + * options to disable these features and then remounted we wouldn't revert the + * settings, because mounting without these features cleared the on-disk + * settings, so this being called on re-mount is not needed. */ -static int btrfs_parse_subvol_options(const char *options, char **subvol_name, - u64 *subvol_objectid) +void btrfs_set_free_space_cache_settings(struct btrfs_fs_info *fs_info) { - substring_t args[MAX_OPT_ARGS]; - char *opts, *orig, *p; - int error = 0; - u64 subvolid; - - if (!options) - return 0; + if (fs_info->sectorsize < PAGE_SIZE) { + btrfs_clear_opt(fs_info->mount_opt, SPACE_CACHE); + if (!btrfs_test_opt(fs_info, FREE_SPACE_TREE)) { + btrfs_info(fs_info, + "forcing free space tree for sector size %u with page size %lu", + fs_info->sectorsize, PAGE_SIZE); + btrfs_set_opt(fs_info->mount_opt, FREE_SPACE_TREE); + } + } /* - * strsep changes the string, duplicate it because - * btrfs_parse_device_options gets called later + * At this point our mount options are populated, so we only mess with + * these settings if we don't have any settings already. */ - opts = kstrdup(options, GFP_KERNEL); - if (!opts) - return -ENOMEM; - orig = opts; + if (btrfs_test_opt(fs_info, FREE_SPACE_TREE)) + return; - while ((p = strsep(&opts, ",")) != NULL) { - int token; - if (!*p) - continue; + if (btrfs_is_zoned(fs_info) && + btrfs_free_space_cache_v1_active(fs_info)) { + btrfs_info(fs_info, "zoned: clearing existing space cache"); + btrfs_set_super_cache_generation(fs_info->super_copy, 0); + return; + } - 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: - error = match_u64(&args[0], &subvolid); - if (error) - goto out; + if (btrfs_test_opt(fs_info, SPACE_CACHE)) + return; - /* we want the original fs_tree */ - if (subvolid == 0) - subvolid = BTRFS_FS_TREE_OBJECTID; + if (btrfs_test_opt(fs_info, NOSPACECACHE)) + return; - *subvol_objectid = subvolid; - break; - default: - break; - } - } + /* + * At this point we don't have explicit options set by the user, set + * them ourselves based on the state of the file system. + */ + if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) + btrfs_set_opt(fs_info->mount_opt, FREE_SPACE_TREE); + else if (btrfs_free_space_cache_v1_active(fs_info)) + btrfs_set_opt(fs_info->mount_opt, SPACE_CACHE); +} -out: - kfree(orig); - return error; +static void set_device_specific_options(struct btrfs_fs_info *fs_info) +{ + if (!btrfs_test_opt(fs_info, NOSSD) && + !fs_info->fs_devices->rotating) + btrfs_set_opt(fs_info->mount_opt, SSD); + + /* + * For devices supporting discard turn on discard=async automatically, + * unless it's already set or disabled. This could be turned off by + * nodiscard for the same mount. + * + * The zoned mode piggy backs on the discard functionality for + * resetting a zone. There is no reason to delay the zone reset as it is + * fast enough. So, do not enable async discard for zoned mode. + */ + if (!(btrfs_test_opt(fs_info, DISCARD_SYNC) || + btrfs_test_opt(fs_info, DISCARD_ASYNC) || + btrfs_test_opt(fs_info, NODISCARD)) && + fs_info->fs_devices->discardable && + !btrfs_is_zoned(fs_info)) + btrfs_set_opt(fs_info->mount_opt, DISCARD_ASYNC); } char *btrfs_get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, @@ -1105,10 +929,6 @@ static int btrfs_fill_super(struct super_block *sb, #endif sb->s_xattr = btrfs_xattr_handlers; sb->s_time_gran = 1; -#ifdef CONFIG_BTRFS_FS_POSIX_ACL - sb->s_flags |= SB_POSIXACL; -#endif - sb->s_flags |= SB_I_VERSION; sb->s_iflags |= SB_I_CGROUPWB; err = super_setup_bdi(sb); @@ -1291,22 +1111,6 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) 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 */ @@ -1382,200 +1186,6 @@ out: return root; } -/* - * Find a superblock for the given device / mount point. - * - * Note: This is based on mount_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_root(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_device *device = NULL; - struct btrfs_fs_devices *fs_devices = NULL; - struct btrfs_fs_info *fs_info = NULL; - void *new_sec_opts = NULL; - blk_mode_t mode = sb_open_mode(flags); - int error = 0; - - if (data) { - error = security_sb_eat_lsm_opts(data, &new_sec_opts); - if (error) - return ERR_PTR(error); - } - - /* - * 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 - * then open_ctree will properly initialize the file system specific - * settings later. btrfs_init_fs_info initializes the static elements - * of the fs_info (locks and such) to make cleanup easier if we find a - * superblock with our given fs_devices later on at sget() time. - */ - fs_info = kvzalloc(sizeof(struct btrfs_fs_info), GFP_KERNEL); - if (!fs_info) { - error = -ENOMEM; - goto error_sec_opts; - } - btrfs_init_fs_info(fs_info); - - fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); - fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); - if (!fs_info->super_copy || !fs_info->super_for_commit) { - error = -ENOMEM; - goto error_fs_info; - } - - mutex_lock(&uuid_mutex); - error = btrfs_parse_device_options(data, mode); - if (error) { - mutex_unlock(&uuid_mutex); - goto error_fs_info; - } - - /* - * With 'true' passed to btrfs_scan_one_device() (mount time) we expect - * either a valid device or an error. - */ - device = btrfs_scan_one_device(device_name, mode, true); - ASSERT(device != NULL); - if (IS_ERR(device)) { - mutex_unlock(&uuid_mutex); - error = PTR_ERR(device); - goto error_fs_info; - } - - fs_devices = device->fs_devices; - fs_info->fs_devices = fs_devices; - - error = btrfs_open_devices(fs_devices, mode, fs_type); - mutex_unlock(&uuid_mutex); - if (error) - goto error_fs_info; - - if (!(flags & SB_RDONLY) && fs_devices->rw_devices == 0) { - error = -EACCES; - goto error_close_devices; - } - - bdev = fs_devices->latest_dev->bdev; - s = sget(fs_type, btrfs_test_super, btrfs_set_super, flags | SB_NOSEC, - fs_info); - if (IS_ERR(s)) { - error = PTR_ERR(s); - goto error_close_devices; - } - - if (s->s_root) { - btrfs_close_devices(fs_devices); - btrfs_free_fs_info(fs_info); - if ((flags ^ s->s_flags) & SB_RDONLY) - error = -EBUSY; - } else { - snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev); - shrinker_debugfs_rename(s->s_shrink, "sb-%s:%s", fs_type->name, - s->s_id); - btrfs_sb(s)->bdev_holder = fs_type; - error = btrfs_fill_super(s, fs_devices, data); - } - if (!error) - error = security_sb_set_mnt_opts(s, new_sec_opts, 0, NULL); - security_free_mnt_opts(&new_sec_opts); - if (error) { - deactivate_locked_super(s); - return ERR_PTR(error); - } - - return dget(s->s_root); - -error_close_devices: - btrfs_close_devices(fs_devices); -error_fs_info: - btrfs_free_fs_info(fs_info); -error_sec_opts: - security_free_mnt_opts(&new_sec_opts); - return ERR_PTR(error); -} - -/* - * Mount function which is called by VFS layer. - * - * In order to allow mounting a subvolume directly, btrfs uses mount_subtree() - * which needs vfsmount* of device's root (/). This means device's root has to - * be mounted internally in any case. - * - * Operation flow: - * 1. Parse subvol id related options for later use in mount_subvol(). - * - * 2. Mount device's root (/) by calling vfs_kern_mount(). - * - * NOTE: vfs_kern_mount() is used by VFS to call btrfs_mount() in the - * first place. In order to avoid calling btrfs_mount() again, we use - * different file_system_type which is not registered to VFS by - * register_filesystem() (btrfs_root_fs_type). As a result, - * btrfs_mount_root() is called. The return value will be used by - * mount_subtree() in mount_subvol(). - * - * 3. Call mount_subvol() to get the dentry of subvolume. Since there is - * "btrfs subvolume set-default", mount_subvol() is called always. - */ -static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, - const char *device_name, void *data) -{ - struct vfsmount *mnt_root; - struct dentry *root; - char *subvol_name = NULL; - u64 subvol_objectid = 0; - int error = 0; - - error = btrfs_parse_subvol_options(data, &subvol_name, - &subvol_objectid); - if (error) { - kfree(subvol_name); - return ERR_PTR(error); - } - - /* mount device's root (/) */ - mnt_root = vfs_kern_mount(&btrfs_root_fs_type, flags, device_name, data); - if (PTR_ERR_OR_ZERO(mnt_root) == -EBUSY) { - if (flags & SB_RDONLY) { - mnt_root = vfs_kern_mount(&btrfs_root_fs_type, - flags & ~SB_RDONLY, device_name, data); - } else { - mnt_root = vfs_kern_mount(&btrfs_root_fs_type, - flags | SB_RDONLY, device_name, data); - if (IS_ERR(mnt_root)) { - root = ERR_CAST(mnt_root); - kfree(subvol_name); - goto out; - } - - down_write(&mnt_root->mnt_sb->s_umount); - error = btrfs_remount(mnt_root->mnt_sb, &flags, NULL); - up_write(&mnt_root->mnt_sb->s_umount); - if (error < 0) { - root = ERR_PTR(error); - mntput(mnt_root); - kfree(subvol_name); - goto out; - } - } - } - if (IS_ERR(mnt_root)) { - root = ERR_CAST(mnt_root); - kfree(subvol_name); - goto out; - } - - /* mount_subvol() will free subvol_name and mnt_root */ - root = mount_subvol(subvol_name, subvol_objectid, mnt_root); - -out: - return root; -} - static void btrfs_resize_thread_pool(struct btrfs_fs_info *fs_info, u32 new_pool_size, u32 old_pool_size) { @@ -1638,202 +1248,282 @@ static inline void btrfs_remount_cleanup(struct btrfs_fs_info *fs_info, btrfs_set_free_space_cache_v1_active(fs_info, cache_opt); } -static int btrfs_remount(struct super_block *sb, int *flags, char *data) +static int btrfs_remount_rw(struct btrfs_fs_info *fs_info) { - struct btrfs_fs_info *fs_info = btrfs_sb(sb); - 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; - u32 old_thread_pool_size = fs_info->thread_pool_size; - u32 old_metadata_ratio = fs_info->metadata_ratio; int ret; - sync_filesystem(sb); - set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); + if (BTRFS_FS_ERROR(fs_info)) { + btrfs_err(fs_info, + "remounting read-write after error is not allowed"); + return -EINVAL; + } - if (data) { - void *new_sec_opts = NULL; + if (fs_info->fs_devices->rw_devices == 0) + return -EACCES; - ret = security_sb_eat_lsm_opts(data, &new_sec_opts); - if (!ret) - ret = security_sb_remount(sb, new_sec_opts); - security_free_mnt_opts(&new_sec_opts); - if (ret) - goto restore; + if (!btrfs_check_rw_degradable(fs_info, NULL)) { + btrfs_warn(fs_info, + "too many missing devices, writable remount is not allowed"); + return -EACCES; + } + + if (btrfs_super_log_root(fs_info->super_copy) != 0) { + btrfs_warn(fs_info, + "mount required to replay tree-log, cannot remount read-write"); + return -EINVAL; } - ret = btrfs_parse_options(fs_info, data, *flags); + /* + * NOTE: when remounting with a change that does writes, don't put it + * anywhere above this point, as we are not sure to be safe to write + * until we pass the above checks. + */ + ret = btrfs_start_pre_rw_mount(fs_info); if (ret) - goto restore; + return ret; - ret = btrfs_check_features(fs_info, !(*flags & SB_RDONLY)); - if (ret < 0) - goto restore; + btrfs_clear_sb_rdonly(fs_info->sb); - btrfs_remount_begin(fs_info, old_opts, *flags); - btrfs_resize_thread_pool(fs_info, - fs_info->thread_pool_size, old_thread_pool_size); + set_bit(BTRFS_FS_OPEN, &fs_info->flags); - if ((bool)btrfs_test_opt(fs_info, FREE_SPACE_TREE) != - (bool)btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) && - (!sb_rdonly(sb) || (*flags & SB_RDONLY))) { - btrfs_warn(fs_info, - "remount supports changing free space tree only from ro to rw"); - /* Make sure free space cache options match the state on disk */ - if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { - btrfs_set_opt(fs_info->mount_opt, FREE_SPACE_TREE); - btrfs_clear_opt(fs_info->mount_opt, SPACE_CACHE); - } - if (btrfs_free_space_cache_v1_active(fs_info)) { - btrfs_clear_opt(fs_info->mount_opt, FREE_SPACE_TREE); - btrfs_set_opt(fs_info->mount_opt, SPACE_CACHE); - } - } + /* + * If we've gone from readonly -> read-write, we need to get our + * sync/async discard lists in the right state. + */ + btrfs_discard_resume(fs_info); - if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) - goto out; + return 0; +} - if (*flags & SB_RDONLY) { - /* - * this also happens on 'umount -rf' or on shutdown, when - * the filesystem is busy. - */ - cancel_work_sync(&fs_info->async_reclaim_work); - cancel_work_sync(&fs_info->async_data_reclaim_work); +static int btrfs_remount_ro(struct btrfs_fs_info *fs_info) +{ + /* + * This also happens on 'umount -rf' or on shutdown, when the + * filesystem is busy. + */ + cancel_work_sync(&fs_info->async_reclaim_work); + cancel_work_sync(&fs_info->async_data_reclaim_work); - btrfs_discard_cleanup(fs_info); + btrfs_discard_cleanup(fs_info); - /* 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); + /* 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); - btrfs_set_sb_rdonly(sb); + btrfs_set_sb_rdonly(fs_info->sb); - /* - * Setting SB_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); + /* + * Setting SB_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); - /* - * The cleaner task could be already running before we set the - * flag BTRFS_FS_STATE_RO (and SB_RDONLY in the superblock). - * We must make sure that after we finish the remount, i.e. after - * we call btrfs_commit_super(), the cleaner can no longer start - * a transaction - either because it was dropping a dead root, - * running delayed iputs or deleting an unused block group (the - * cleaner picked a block group from the list of unused block - * groups before we were able to in the previous call to - * btrfs_delete_unused_bgs()). - */ - wait_on_bit(&fs_info->flags, BTRFS_FS_CLEANER_RUNNING, - TASK_UNINTERRUPTIBLE); + /* + * The cleaner task could be already running before we set the flag + * BTRFS_FS_STATE_RO (and SB_RDONLY in the superblock). We must make + * sure that after we finish the remount, i.e. after we call + * btrfs_commit_super(), the cleaner can no longer start a transaction + * - either because it was dropping a dead root, running delayed iputs + * or deleting an unused block group (the cleaner picked a block + * group from the list of unused block groups before we were able to + * in the previous call to btrfs_delete_unused_bgs()). + */ + wait_on_bit(&fs_info->flags, BTRFS_FS_CLEANER_RUNNING, TASK_UNINTERRUPTIBLE); - /* - * We've set the superblock to RO mode, so we might have made - * the cleaner task sleep without running all pending delayed - * iputs. Go through all the delayed iputs here, so that if an - * unmount happens without remounting RW we don't end up at - * finishing close_ctree() with a non-empty list of delayed - * iputs. - */ - btrfs_run_delayed_iputs(fs_info); + /* + * We've set the superblock to RO mode, so we might have made the + * cleaner task sleep without running all pending delayed iputs. Go + * through all the delayed iputs here, so that if an unmount happens + * without remounting RW we don't end up at finishing close_ctree() + * with a non-empty list of delayed iputs. + */ + btrfs_run_delayed_iputs(fs_info); - btrfs_dev_replace_suspend_for_unmount(fs_info); - btrfs_scrub_cancel(fs_info); - btrfs_pause_balance(fs_info); + btrfs_dev_replace_suspend_for_unmount(fs_info); + btrfs_scrub_cancel(fs_info); + btrfs_pause_balance(fs_info); - /* - * Pause the qgroup rescan worker if it is running. We don't want - * it to be still running after we are in RO mode, as after that, - * by the time we unmount, it might have left a transaction open, - * so we would leak the transaction and/or crash. - */ - btrfs_qgroup_wait_for_completion(fs_info, false); + /* + * Pause the qgroup rescan worker if it is running. We don't want it to + * be still running after we are in RO mode, as after that, by the time + * we unmount, it might have left a transaction open, so we would leak + * the transaction and/or crash. + */ + btrfs_qgroup_wait_for_completion(fs_info, false); - ret = btrfs_commit_super(fs_info); - if (ret) - goto restore; - } else { - if (BTRFS_FS_ERROR(fs_info)) { - 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; - } + return btrfs_commit_super(fs_info); +} - if (!btrfs_check_rw_degradable(fs_info, NULL)) { - btrfs_warn(fs_info, - "too many missing devices, writable remount is not allowed"); - ret = -EACCES; - goto restore; - } +static void btrfs_ctx_to_info(struct btrfs_fs_info *fs_info, struct btrfs_fs_context *ctx) +{ + fs_info->max_inline = ctx->max_inline; + fs_info->commit_interval = ctx->commit_interval; + fs_info->metadata_ratio = ctx->metadata_ratio; + fs_info->thread_pool_size = ctx->thread_pool_size; + fs_info->mount_opt = ctx->mount_opt; + fs_info->compress_type = ctx->compress_type; + fs_info->compress_level = ctx->compress_level; +} - if (btrfs_super_log_root(fs_info->super_copy) != 0) { - btrfs_warn(fs_info, - "mount required to replay tree-log, cannot remount read-write"); - ret = -EINVAL; - goto restore; - } +static void btrfs_info_to_ctx(struct btrfs_fs_info *fs_info, struct btrfs_fs_context *ctx) +{ + ctx->max_inline = fs_info->max_inline; + ctx->commit_interval = fs_info->commit_interval; + ctx->metadata_ratio = fs_info->metadata_ratio; + ctx->thread_pool_size = fs_info->thread_pool_size; + ctx->mount_opt = fs_info->mount_opt; + ctx->compress_type = fs_info->compress_type; + ctx->compress_level = fs_info->compress_level; +} - /* - * NOTE: when remounting with a change that does writes, don't - * put it anywhere above this point, as we are not sure to be - * safe to write until we pass the above checks. - */ - ret = btrfs_start_pre_rw_mount(fs_info); - if (ret) - goto restore; +#define btrfs_info_if_set(fs_info, old_ctx, opt, fmt, args...) \ +do { \ + if ((!old_ctx || !btrfs_raw_test_opt(old_ctx->mount_opt, opt)) && \ + btrfs_raw_test_opt(fs_info->mount_opt, opt)) \ + btrfs_info(fs_info, fmt, ##args); \ +} while (0) + +#define btrfs_info_if_unset(fs_info, old_ctx, opt, fmt, args...) \ +do { \ + if ((old_ctx && btrfs_raw_test_opt(old_ctx->mount_opt, opt)) && \ + !btrfs_raw_test_opt(fs_info->mount_opt, opt)) \ + btrfs_info(fs_info, fmt, ##args); \ +} while (0) + +static void btrfs_emit_options(struct btrfs_fs_info *info, + struct btrfs_fs_context *old) +{ + btrfs_info_if_set(info, old, NODATASUM, "setting nodatasum"); + btrfs_info_if_set(info, old, DEGRADED, "allowing degraded mounts"); + btrfs_info_if_set(info, old, NODATASUM, "setting nodatasum"); + btrfs_info_if_set(info, old, SSD, "enabling ssd optimizations"); + btrfs_info_if_set(info, old, SSD_SPREAD, "using spread ssd allocation scheme"); + btrfs_info_if_set(info, old, NOBARRIER, "turning off barriers"); + btrfs_info_if_set(info, old, NOTREELOG, "disabling tree log"); + btrfs_info_if_set(info, old, NOLOGREPLAY, "disabling log replay at mount time"); + btrfs_info_if_set(info, old, FLUSHONCOMMIT, "turning on flush-on-commit"); + btrfs_info_if_set(info, old, DISCARD_SYNC, "turning on sync discard"); + btrfs_info_if_set(info, old, DISCARD_ASYNC, "turning on async discard"); + btrfs_info_if_set(info, old, FREE_SPACE_TREE, "enabling free space tree"); + btrfs_info_if_set(info, old, SPACE_CACHE, "enabling disk space caching"); + btrfs_info_if_set(info, old, CLEAR_CACHE, "force clearing of disk cache"); + btrfs_info_if_set(info, old, AUTO_DEFRAG, "enabling auto defrag"); + btrfs_info_if_set(info, old, FRAGMENT_DATA, "fragmenting data"); + btrfs_info_if_set(info, old, FRAGMENT_METADATA, "fragmenting metadata"); + btrfs_info_if_set(info, old, REF_VERIFY, "doing ref verification"); + btrfs_info_if_set(info, old, USEBACKUPROOT, "trying to use backup root at mount time"); + btrfs_info_if_set(info, old, IGNOREBADROOTS, "ignoring bad roots"); + btrfs_info_if_set(info, old, IGNOREDATACSUMS, "ignoring data csums"); + + btrfs_info_if_unset(info, old, NODATACOW, "setting datacow"); + btrfs_info_if_unset(info, old, SSD, "not using ssd optimizations"); + btrfs_info_if_unset(info, old, SSD_SPREAD, "not using spread ssd allocation scheme"); + btrfs_info_if_unset(info, old, NOBARRIER, "turning off barriers"); + btrfs_info_if_unset(info, old, NOTREELOG, "enabling tree log"); + btrfs_info_if_unset(info, old, SPACE_CACHE, "disabling disk space caching"); + btrfs_info_if_unset(info, old, FREE_SPACE_TREE, "disabling free space tree"); + btrfs_info_if_unset(info, old, AUTO_DEFRAG, "disabling auto defrag"); + btrfs_info_if_unset(info, old, COMPRESS, "use no compression"); + + /* Did the compression settings change? */ + if (btrfs_test_opt(info, COMPRESS) && + (!old || + old->compress_type != info->compress_type || + old->compress_level != info->compress_level || + (!btrfs_raw_test_opt(old->mount_opt, FORCE_COMPRESS) && + btrfs_raw_test_opt(info->mount_opt, FORCE_COMPRESS)))) { + const char *compress_type = btrfs_compress_type2str(info->compress_type); + + btrfs_info(info, "%s %s compression, level %d", + btrfs_test_opt(info, FORCE_COMPRESS) ? "force" : "use", + compress_type, info->compress_level); + } - btrfs_clear_sb_rdonly(sb); + if (info->max_inline != BTRFS_DEFAULT_MAX_INLINE) + btrfs_info(info, "max_inline set to %llu", info->max_inline); +} - set_bit(BTRFS_FS_OPEN, &fs_info->flags); +static int btrfs_reconfigure(struct fs_context *fc) +{ + struct super_block *sb = fc->root->d_sb; + struct btrfs_fs_info *fs_info = btrfs_sb(sb); + struct btrfs_fs_context *ctx = fc->fs_private; + struct btrfs_fs_context old_ctx; + int ret = 0; + bool mount_reconfigure = (fc->s_fs_info != NULL); - /* - * If we've gone from readonly -> read/write, we need to get - * our sync/async discard lists in the right state. - */ - btrfs_discard_resume(fs_info); + btrfs_info_to_ctx(fs_info, &old_ctx); + + /* + * This is our "bind mount" trick, we don't want to allow the user to do + * anything other than mount a different ro/rw and a different subvol, + * all of the mount options should be maintained. + */ + if (mount_reconfigure) + ctx->mount_opt = old_ctx.mount_opt; + + sync_filesystem(sb); + set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); + + if (!mount_reconfigure && + !btrfs_check_options(fs_info, &ctx->mount_opt, fc->sb_flags)) + return -EINVAL; + + ret = btrfs_check_features(fs_info, !(fc->sb_flags & SB_RDONLY)); + if (ret < 0) + return ret; + + btrfs_ctx_to_info(fs_info, ctx); + btrfs_remount_begin(fs_info, old_ctx.mount_opt, fc->sb_flags); + btrfs_resize_thread_pool(fs_info, fs_info->thread_pool_size, + old_ctx.thread_pool_size); + + if ((bool)btrfs_test_opt(fs_info, FREE_SPACE_TREE) != + (bool)btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) && + (!sb_rdonly(sb) || (fc->sb_flags & SB_RDONLY))) { + btrfs_warn(fs_info, + "remount supports changing free space tree only from RO to RW"); + /* Make sure free space cache options match the state on disk. */ + if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + btrfs_set_opt(fs_info->mount_opt, FREE_SPACE_TREE); + btrfs_clear_opt(fs_info->mount_opt, SPACE_CACHE); + } + if (btrfs_free_space_cache_v1_active(fs_info)) { + btrfs_clear_opt(fs_info->mount_opt, FREE_SPACE_TREE); + btrfs_set_opt(fs_info->mount_opt, SPACE_CACHE); + } } -out: + + ret = 0; + if (!sb_rdonly(sb) && (fc->sb_flags & SB_RDONLY)) + ret = btrfs_remount_ro(fs_info); + else if (sb_rdonly(sb) && !(fc->sb_flags & SB_RDONLY)) + ret = btrfs_remount_rw(fs_info); + if (ret) + goto restore; + /* - * We need to set SB_I_VERSION here otherwise it'll get cleared by VFS, - * since the absence of the flag means it can be toggled off by remount. + * If we set the mask during the parameter parsing VFS would reject the + * remount. Here we can set the mask and the value will be updated + * appropriately. */ - *flags |= SB_I_VERSION; + if ((fc->sb_flags & SB_POSIXACL) != (sb->s_flags & SB_POSIXACL)) + fc->sb_flags_mask |= SB_POSIXACL; + btrfs_emit_options(fs_info, &old_ctx); wake_up_process(fs_info->transaction_kthread); - btrfs_remount_cleanup(fs_info, old_opts); + btrfs_remount_cleanup(fs_info, old_ctx.mount_opt); btrfs_clear_oneshot_options(fs_info); clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); return 0; - restore: - /* We've hit an error - don't reset SB_RDONLY */ - if (sb_rdonly(sb)) - old_flags |= SB_RDONLY; - if (!(old_flags & SB_RDONLY)) - clear_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state); - 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; - 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); + btrfs_ctx_to_info(fs_info, &old_ctx); + btrfs_remount_cleanup(fs_info, old_ctx.mount_opt); clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); - return ret; } @@ -2077,7 +1767,7 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) buf->f_bavail = 0; buf->f_type = BTRFS_SUPER_MAGIC; - buf->f_bsize = dentry->d_sb->s_blocksize; + buf->f_bsize = fs_info->sectorsize; buf->f_namelen = BTRFS_NAME_LEN; /* We treat it as constant endianness (it doesn't matter _which_) @@ -2094,6 +1784,309 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) return 0; } +static int btrfs_fc_test_super(struct super_block *sb, struct fs_context *fc) +{ + struct btrfs_fs_info *p = fc->s_fs_info; + struct btrfs_fs_info *fs_info = btrfs_sb(sb); + + return fs_info->fs_devices == p->fs_devices; +} + +static int btrfs_get_tree_super(struct fs_context *fc) +{ + struct btrfs_fs_info *fs_info = fc->s_fs_info; + struct btrfs_fs_context *ctx = fc->fs_private; + struct btrfs_fs_devices *fs_devices = NULL; + struct block_device *bdev; + struct btrfs_device *device; + struct super_block *sb; + blk_mode_t mode = btrfs_open_mode(fc); + int ret; + + btrfs_ctx_to_info(fs_info, ctx); + mutex_lock(&uuid_mutex); + + /* + * With 'true' passed to btrfs_scan_one_device() (mount time) we expect + * either a valid device or an error. + */ + device = btrfs_scan_one_device(fc->source, mode, true); + ASSERT(device != NULL); + if (IS_ERR(device)) { + mutex_unlock(&uuid_mutex); + return PTR_ERR(device); + } + + fs_devices = device->fs_devices; + fs_info->fs_devices = fs_devices; + + ret = btrfs_open_devices(fs_devices, mode, &btrfs_fs_type); + mutex_unlock(&uuid_mutex); + if (ret) + return ret; + + if (!(fc->sb_flags & SB_RDONLY) && fs_devices->rw_devices == 0) { + ret = -EACCES; + goto error; + } + + bdev = fs_devices->latest_dev->bdev; + + /* + * From now on the error handling is not straightforward. + * + * If successful, this will transfer the fs_info into the super block, + * and fc->s_fs_info will be NULL. However if there's an existing + * super, we'll still have fc->s_fs_info populated. If we error + * completely out it'll be cleaned up when we drop the fs_context, + * otherwise it's tied to the lifetime of the super_block. + */ + sb = sget_fc(fc, btrfs_fc_test_super, set_anon_super_fc); + if (IS_ERR(sb)) { + ret = PTR_ERR(sb); + goto error; + } + + set_device_specific_options(fs_info); + + if (sb->s_root) { + btrfs_close_devices(fs_devices); + if ((fc->sb_flags ^ sb->s_flags) & SB_RDONLY) + ret = -EBUSY; + } else { + snprintf(sb->s_id, sizeof(sb->s_id), "%pg", bdev); + shrinker_debugfs_rename(sb->s_shrink, "sb-btrfs:%s", sb->s_id); + btrfs_sb(sb)->bdev_holder = &btrfs_fs_type; + ret = btrfs_fill_super(sb, fs_devices, NULL); + } + + if (ret) { + deactivate_locked_super(sb); + return ret; + } + + btrfs_clear_oneshot_options(fs_info); + + fc->root = dget(sb->s_root); + return 0; + +error: + btrfs_close_devices(fs_devices); + return ret; +} + +/* + * Ever since commit 0723a0473fb4 ("btrfs: allow mounting btrfs subvolumes + * with different ro/rw options") the following works: + * + * (i) mount /dev/sda3 -o subvol=foo,ro /mnt/foo + * (ii) mount /dev/sda3 -o subvol=bar,rw /mnt/bar + * + * which looks nice and innocent but is actually pretty intricate and deserves + * a long comment. + * + * On another filesystem a subvolume mount is close to something like: + * + * (iii) # create rw superblock + initial mount + * mount -t xfs /dev/sdb /opt/ + * + * # create ro bind mount + * mount --bind -o ro /opt/foo /mnt/foo + * + * # unmount initial mount + * umount /opt + * + * Of course, there's some special subvolume sauce and there's the fact that the + * sb->s_root dentry is really swapped after mount_subtree(). But conceptually + * it's very close and will help us understand the issue. + * + * The old mount API didn't cleanly distinguish between a mount being made ro + * and a superblock being made ro. The only way to change the ro state of + * either object was by passing ms_rdonly. If a new mount was created via + * mount(2) such as: + * + * mount("/dev/sdb", "/mnt", "xfs", ms_rdonly, null); + * + * the MS_RDONLY flag being specified had two effects: + * + * (1) MNT_READONLY was raised -> the resulting mount got + * @mnt->mnt_flags |= MNT_READONLY raised. + * + * (2) MS_RDONLY was passed to the filesystem's mount method and the filesystems + * made the superblock ro. Note, how SB_RDONLY has the same value as + * ms_rdonly and is raised whenever MS_RDONLY is passed through mount(2). + * + * Creating a subtree mount via (iii) ends up leaving a rw superblock with a + * subtree mounted ro. + * + * But consider the effect on the old mount API on btrfs subvolume mounting + * which combines the distinct step in (iii) into a single step. + * + * By issuing (i) both the mount and the superblock are turned ro. Now when (ii) + * is issued the superblock is ro and thus even if the mount created for (ii) is + * rw it wouldn't help. Hence, btrfs needed to transition the superblock from ro + * to rw for (ii) which it did using an internal remount call. + * + * IOW, subvolume mounting was inherently complicated due to the ambiguity of + * MS_RDONLY in mount(2). Note, this ambiguity has mount(8) always translate + * "ro" to MS_RDONLY. IOW, in both (i) and (ii) "ro" becomes MS_RDONLY when + * passed by mount(8) to mount(2). + * + * Enter the new mount API. The new mount API disambiguates making a mount ro + * and making a superblock ro. + * + * (3) To turn a mount ro the MOUNT_ATTR_ONLY flag can be used with either + * fsmount() or mount_setattr() this is a pure VFS level change for a + * specific mount or mount tree that is never seen by the filesystem itself. + * + * (4) To turn a superblock ro the "ro" flag must be used with + * fsconfig(FSCONFIG_SET_FLAG, "ro"). This option is seen by the filesystem + * in fc->sb_flags. + * + * This disambiguation has rather positive consequences. Mounting a subvolume + * ro will not also turn the superblock ro. Only the mount for the subvolume + * will become ro. + * + * So, if the superblock creation request comes from the new mount API the + * caller must have explicitly done: + * + * fsconfig(FSCONFIG_SET_FLAG, "ro") + * fsmount/mount_setattr(MOUNT_ATTR_RDONLY) + * + * IOW, at some point the caller must have explicitly turned the whole + * superblock ro and we shouldn't just undo it like we did for the old mount + * API. In any case, it lets us avoid the hack in the new mount API. + * + * Consequently, the remounting hack must only be used for requests originating + * from the old mount API and should be marked for full deprecation so it can be + * turned off in a couple of years. + * + * The new mount API has no reason to support this hack. + */ +static struct vfsmount *btrfs_reconfigure_for_mount(struct fs_context *fc) +{ + struct vfsmount *mnt; + int ret; + const bool ro2rw = !(fc->sb_flags & SB_RDONLY); + + /* + * We got an EBUSY because our SB_RDONLY flag didn't match the existing + * super block, so invert our setting here and retry the mount so we + * can get our vfsmount. + */ + if (ro2rw) + fc->sb_flags |= SB_RDONLY; + else + fc->sb_flags &= ~SB_RDONLY; + + mnt = fc_mount(fc); + if (IS_ERR(mnt)) + return mnt; + + if (!fc->oldapi || !ro2rw) + return mnt; + + /* We need to convert to rw, call reconfigure. */ + fc->sb_flags &= ~SB_RDONLY; + down_write(&mnt->mnt_sb->s_umount); + ret = btrfs_reconfigure(fc); + up_write(&mnt->mnt_sb->s_umount); + if (ret) { + mntput(mnt); + return ERR_PTR(ret); + } + return mnt; +} + +static int btrfs_get_tree_subvol(struct fs_context *fc) +{ + struct btrfs_fs_info *fs_info = NULL; + struct btrfs_fs_context *ctx = fc->fs_private; + struct fs_context *dup_fc; + struct dentry *dentry; + struct vfsmount *mnt; + + /* + * 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 + * then open_ctree will properly initialize the file system specific + * settings later. btrfs_init_fs_info initializes the static elements + * of the fs_info (locks and such) to make cleanup easier if we find a + * superblock with our given fs_devices later on at sget() time. + */ + fs_info = kvzalloc(sizeof(struct btrfs_fs_info), GFP_KERNEL); + if (!fs_info) + return -ENOMEM; + + fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); + fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); + if (!fs_info->super_copy || !fs_info->super_for_commit) { + btrfs_free_fs_info(fs_info); + return -ENOMEM; + } + btrfs_init_fs_info(fs_info); + + dup_fc = vfs_dup_fs_context(fc); + if (IS_ERR(dup_fc)) { + btrfs_free_fs_info(fs_info); + return PTR_ERR(dup_fc); + } + + /* + * When we do the sget_fc this gets transferred to the sb, so we only + * need to set it on the dup_fc as this is what creates the super block. + */ + dup_fc->s_fs_info = fs_info; + + /* + * We'll do the security settings in our btrfs_get_tree_super() mount + * loop, they were duplicated into dup_fc, we can drop the originals + * here. + */ + security_free_mnt_opts(&fc->security); + fc->security = NULL; + + mnt = fc_mount(dup_fc); + if (PTR_ERR_OR_ZERO(mnt) == -EBUSY) + mnt = btrfs_reconfigure_for_mount(dup_fc); + put_fs_context(dup_fc); + if (IS_ERR(mnt)) + return PTR_ERR(mnt); + + /* + * This free's ->subvol_name, because if it isn't set we have to + * allocate a buffer to hold the subvol_name, so we just drop our + * reference to it here. + */ + dentry = mount_subvol(ctx->subvol_name, ctx->subvol_objectid, mnt); + ctx->subvol_name = NULL; + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + + fc->root = dentry; + return 0; +} + +static int btrfs_get_tree(struct fs_context *fc) +{ + /* + * Since we use mount_subtree to mount the default/specified subvol, we + * have to do mounts in two steps. + * + * First pass through we call btrfs_get_tree_subvol(), this is just a + * wrapper around fc_mount() to call back into here again, and this time + * we'll call btrfs_get_tree_super(). This will do the open_ctree() and + * everything to open the devices and file system. Then we return back + * with a fully constructed vfsmount in btrfs_get_tree_subvol(), and + * from there we can do our mount_subvol() call, which will lookup + * whichever subvol we're mounting and setup this fc with the + * appropriate dentry for the subvol. + */ + if (fc->s_fs_info) + return btrfs_get_tree_super(fc); + return btrfs_get_tree_subvol(fc); +} + static void btrfs_kill_super(struct super_block *sb) { struct btrfs_fs_info *fs_info = btrfs_sb(sb); @@ -2101,22 +2094,85 @@ static void btrfs_kill_super(struct super_block *sb) btrfs_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, -}; +static void btrfs_free_fs_context(struct fs_context *fc) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + struct btrfs_fs_info *fs_info = fc->s_fs_info; + + if (fs_info) + btrfs_free_fs_info(fs_info); + + if (ctx && refcount_dec_and_test(&ctx->refs)) { + kfree(ctx->subvol_name); + kfree(ctx); + } +} + +static int btrfs_dup_fs_context(struct fs_context *fc, struct fs_context *src_fc) +{ + struct btrfs_fs_context *ctx = src_fc->fs_private; -static struct file_system_type btrfs_root_fs_type = { - .owner = THIS_MODULE, - .name = "btrfs", - .mount = btrfs_mount_root, - .kill_sb = btrfs_kill_super, - .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA | FS_ALLOW_IDMAP, + /* + * Give a ref to our ctx to this dup, as we want to keep it around for + * our original fc so we can have the subvolume name or objectid. + * + * We unset ->source in the original fc because the dup needs it for + * mounting, and then once we free the dup it'll free ->source, so we + * need to make sure we're only pointing to it in one fc. + */ + refcount_inc(&ctx->refs); + fc->fs_private = ctx; + fc->source = src_fc->source; + src_fc->source = NULL; + return 0; +} + +static const struct fs_context_operations btrfs_fs_context_ops = { + .parse_param = btrfs_parse_param, + .reconfigure = btrfs_reconfigure, + .get_tree = btrfs_get_tree, + .dup = btrfs_dup_fs_context, + .free = btrfs_free_fs_context, }; +static int btrfs_init_fs_context(struct fs_context *fc) +{ + struct btrfs_fs_context *ctx; + + ctx = kzalloc(sizeof(struct btrfs_fs_context), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + refcount_set(&ctx->refs, 1); + fc->fs_private = ctx; + fc->ops = &btrfs_fs_context_ops; + + if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) { + btrfs_info_to_ctx(btrfs_sb(fc->root->d_sb), ctx); + } else { + ctx->thread_pool_size = + min_t(unsigned long, num_online_cpus() + 2, 8); + ctx->max_inline = BTRFS_DEFAULT_MAX_INLINE; + ctx->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL; + } + +#ifdef CONFIG_BTRFS_FS_POSIX_ACL + fc->sb_flags |= SB_POSIXACL; +#endif + fc->sb_flags |= SB_I_VERSION; + + return 0; +} + +static struct file_system_type btrfs_fs_type = { + .owner = THIS_MODULE, + .name = "btrfs", + .init_fs_context = btrfs_init_fs_context, + .parameters = btrfs_fs_parameters, + .kill_sb = btrfs_kill_super, + .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA | FS_ALLOW_IDMAP, + }; + MODULE_ALIAS_FS("btrfs"); static int btrfs_control_open(struct inode *inode, struct file *file) @@ -2328,7 +2384,6 @@ static const struct super_operations btrfs_super_ops = { .destroy_inode = btrfs_destroy_inode, .free_inode = btrfs_free_inode, .statfs = btrfs_statfs, - .remount_fs = btrfs_remount, .freeze_fs = btrfs_freeze, .unfreeze_fs = btrfs_unfreeze, }; |