bcachefs: Fix nochanges/read_only interaction
nochanges means "we cannot issue writes at all"; it's possible to go
into a pseudo read-write mode where we pin dirty metadata in memory,
which is used for fsck in dry run mode and doing journal replay on a
read only mount, but we do not want to allow an actual read-write mount
in nochanges mode.
But we do always want to allow early read-write, during recovery - this
patch clarifies that.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
diff --git a/fs/bcachefs/fs.c b/fs/bcachefs/fs.c
index 12de97b..da117576 100644
--- a/fs/bcachefs/fs.c
+++ b/fs/bcachefs/fs.c
@@ -1630,12 +1630,12 @@ static int bch2_remount(struct super_block *sb, int *flags, char *data)
struct bch_opts opts = bch2_opts_empty();
int ret;
- opt_set(opts, read_only, (*flags & SB_RDONLY) != 0);
-
ret = bch2_parse_mount_opts(c, &opts, data);
if (ret)
goto err;
+ opt_set(opts, read_only, (*flags & SB_RDONLY) != 0);
+
if (opts.read_only != c->opts.read_only) {
down_write(&c->state_lock);
diff --git a/fs/bcachefs/opts.h b/fs/bcachefs/opts.h
index cf69b92..42cad83 100644
--- a/fs/bcachefs/opts.h
+++ b/fs/bcachefs/opts.h
@@ -389,7 +389,7 @@ enum fsck_err_opts {
BCH2_NO_SB_OPT, BCH_SB_SECTOR, \
"offset", "Sector offset of superblock") \
x(read_only, u8, \
- OPT_FS, \
+ OPT_FS|OPT_MOUNT, \
OPT_BOOL(), \
BCH2_NO_SB_OPT, false, \
NULL, NULL) \
diff --git a/fs/bcachefs/recovery.c b/fs/bcachefs/recovery.c
index a792f42..d2914e9 100644
--- a/fs/bcachefs/recovery.c
+++ b/fs/bcachefs/recovery.c
@@ -1076,7 +1076,9 @@ int bch2_fs_recovery(struct bch_fs *c)
bch2_journal_keys_put_initial(c);
kfree(clean);
- if (!ret && test_bit(BCH_FS_need_delete_dead_snapshots, &c->flags)) {
+ if (!ret &&
+ test_bit(BCH_FS_need_delete_dead_snapshots, &c->flags) &&
+ !c->opts.nochanges) {
bch2_fs_read_write_early(c);
bch2_delete_dead_snapshots_async(c);
}
diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c
index 592005b..492dfd4 100644
--- a/fs/bcachefs/super.c
+++ b/fs/bcachefs/super.c
@@ -433,16 +433,6 @@ static int __bch2_fs_read_write(struct bch_fs *c, bool early)
if (test_bit(BCH_FS_rw, &c->flags))
return 0;
- if (c->opts.norecovery)
- return -BCH_ERR_erofs_norecovery;
-
- /*
- * nochanges is used for fsck -n mode - we have to allow going rw
- * during recovery for that to work:
- */
- if (c->opts.nochanges && (!early || c->opts.read_only))
- return -BCH_ERR_erofs_nochanges;
-
bch_info(c, "going read-write");
ret = bch2_sb_members_v2_init(c);
@@ -510,6 +500,12 @@ static int __bch2_fs_read_write(struct bch_fs *c, bool early)
int bch2_fs_read_write(struct bch_fs *c)
{
+ if (c->opts.norecovery)
+ return -BCH_ERR_erofs_norecovery;
+
+ if (c->opts.nochanges)
+ return -BCH_ERR_erofs_nochanges;
+
return __bch2_fs_read_write(c, false);
}
@@ -1033,7 +1029,7 @@ int bch2_fs_start(struct bch_fs *c)
set_bit(BCH_FS_started, &c->flags);
- if (c->opts.read_only || c->opts.nochanges) {
+ if (c->opts.read_only) {
bch2_fs_read_only(c);
} else {
ret = !test_bit(BCH_FS_rw, &c->flags)
@@ -1946,6 +1942,11 @@ struct bch_fs *bch2_fs_open(char * const *devices, unsigned nr_devices,
BUG_ON(darray_push(&sbs, sb));
}
+ if (opts.nochanges && !opts.read_only) {
+ ret = -BCH_ERR_erofs_nochanges;
+ goto err_print;
+ }
+
darray_for_each(sbs, sb)
if (!best || le64_to_cpu(sb->sb->seq) > le64_to_cpu(best->sb->seq))
best = sb;
