bcachefs: Make sure c->vfs_sb is set before starting fs

This is necessary for the new blk_holder_ops, which want the vfs
super_block available for synchronization.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/fs.c b/fs/bcachefs/fs.c
index 2c011a465588571a7cd15f54b24c2f6598a76744..459ca8259fc024f5a4eb91ee93e602ca00b73db4 100644 (file)
--- a/fs/bcachefs/fs.c
+++ b/fs/bcachefs/fs.c
@@ -2218,9 +2218,10 @@ static int bch2_fs_get_tree(struct fs_context *fc)
 
        bch2_opts_apply(&c->opts, opts);
 
-       ret = bch2_fs_start(c);
-       if (ret)
-               goto err_stop_fs;
+       /*
+        * need to initialise sb and set c->vfs_sb _before_ starting fs,
+        * for blk_holder_ops
+        */
 
        sb = sget(fc->fs_type, NULL, bch2_set_super, fc->sb_flags|SB_NOSEC, c);
        ret = PTR_ERR_OR_ZERO(sb);
@@ -2282,6 +2283,10 @@ got_sb:
 
        sb->s_shrink->seeks = 0;
 
+       ret = bch2_fs_start(c);
+       if (ret)
+               goto err_put_super;
+
        vinode = bch2_vfs_inode_get(c, BCACHEFS_ROOT_SUBVOL_INUM);
        ret = PTR_ERR_OR_ZERO(vinode);
        bch_err_msg(c, ret, "mounting: error getting root inode");