This patch introduces a new "rescue=" mount option group for all those mount options for data recovery.
Different rescue sub options are seperated by ':'. E.g "ro,rescue=nologreplay:usebackuproot". (The original plan is to use ';', but ';' needs to be escaped/quoted, or it will be interpreted by bash) And obviously, user can specify rescue options one by one like: "ro,rescue=nologreplay,rescue=usebackuproot" The following mount options are converted to "rescue=", old mount options are deprecated but still available for compatibility purpose: - usebackuproot Now it's "rescue=usebackuproot" - nologreplay Now it's "rescue=nologreplay" Signed-off-by: Qu Wenruo <w...@suse.com> --- fs/btrfs/super.c | 79 +++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 71 insertions(+), 8 deletions(-) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 78de9d5d80c6..13907a6d2a87 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -311,7 +311,6 @@ enum { Opt_datasum, Opt_nodatasum, Opt_defrag, Opt_nodefrag, Opt_discard, Opt_nodiscard, - Opt_nologreplay, Opt_norecovery, Opt_ratio, Opt_rescan_uuid_tree, @@ -325,9 +324,13 @@ enum { Opt_subvolid, Opt_thread_pool, Opt_treelog, Opt_notreelog, - Opt_usebackuproot, Opt_user_subvol_rm_allowed, + /* Rescue options */ + Opt_rescue, + Opt_usebackuproot, + Opt_nologreplay, + /* Deprecated options */ Opt_alloc_start, Opt_recovery, @@ -374,7 +377,6 @@ static const match_table_t tokens = { {Opt_nodefrag, "noautodefrag"}, {Opt_discard, "discard"}, {Opt_nodiscard, "nodiscard"}, - {Opt_nologreplay, "nologreplay"}, {Opt_norecovery, "norecovery"}, {Opt_ratio, "metadata_ratio=%u"}, {Opt_rescan_uuid_tree, "rescan_uuid_tree"}, @@ -392,9 +394,13 @@ static const match_table_t tokens = { {Opt_thread_pool, "thread_pool=%u"}, {Opt_treelog, "treelog"}, {Opt_notreelog, "notreelog"}, - {Opt_usebackuproot, "usebackuproot"}, {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, + /* Recovery options */ + {Opt_rescue, "rescue=%s"}, + {Opt_nologreplay, "nologreplay"}, + {Opt_usebackuproot, "usebackuproot"}, + /* Deprecated options */ {Opt_alloc_start, "alloc_start=%s"}, {Opt_recovery, "recovery"}, @@ -417,6 +423,55 @@ static const match_table_t tokens = { {Opt_err, NULL}, }; +static const match_table_t rescue_tokens = { + {Opt_usebackuproot, "usebackuproot"}, + {Opt_nologreplay, "nologreplay"}, + {Opt_err, NULL}, +}; + +static int parse_rescue_options(struct btrfs_fs_info *info, const char *options) +{ + char *opts; + char *orig; + char *p; + substring_t args[MAX_OPT_ARGS]; + int ret = 0; + + 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, 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_err: + btrfs_info(info, "unrecognized rescue option '%s'", p); + ret = -EINVAL; + goto out; + default: + break; + } + + } +out: + kfree(orig); + return ret; +} + /* * Regular mount options parser. Everything that is needed only when * reading in a new superblock is parsed here. @@ -673,6 +728,8 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options, break; case Opt_norecovery: case Opt_nologreplay: + btrfs_warn(info, + "'nologreplay' is deprecated, use 'rescue=nologreplay' instead"); btrfs_set_and_info(info, NOLOGREPLAY, "disabling log replay at mount time"); break; @@ -761,10 +818,11 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options, "disabling auto defrag"); break; case Opt_recovery: - btrfs_warn(info, - "'recovery' is deprecated, use 'usebackuproot' instead"); - /* fall through */ 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); @@ -851,6 +909,11 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options, btrfs_set_opt(info->mount_opt, REF_VERIFY); break; #endif + case Opt_rescue: + ret = parse_rescue_options(info, args[0].from); + if (ret < 0) + goto out; + break; case Opt_err: btrfs_info(info, "unrecognized mount option '%s'", p); ret = -EINVAL; @@ -1317,7 +1380,7 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) if (btrfs_test_opt(info, NOTREELOG)) seq_puts(seq, ",notreelog"); if (btrfs_test_opt(info, NOLOGREPLAY)) - seq_puts(seq, ",nologreplay"); + seq_puts(seq, ",rescue=no_log_replay"); if (btrfs_test_opt(info, FLUSHONCOMMIT)) seq_puts(seq, ",flushoncommit"); if (btrfs_test_opt(info, DISCARD)) -- 2.23.0