summaryrefslogtreecommitdiffstats
path: root/fs/btrfs/super.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 18:50:12 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 18:50:12 +0000
commit8665bd53f2f2e27e5511d90428cb3f60e6d0ce15 (patch)
tree8d58900dc0ebd4a3011f92c128d2fe45bc7c4bf2 /fs/btrfs/super.c
parentAdding debian version 6.7.12-1. (diff)
downloadlinux-8665bd53f2f2e27e5511d90428cb3f60e6d0ce15.tar.xz
linux-8665bd53f2f2e27e5511d90428cb3f60e6d0ce15.zip
Merging upstream version 6.8.9.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/btrfs/super.c')
-rw-r--r--fs/btrfs/super.c2301
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,
};