From 20b450773d17e325190c158e10bfdb25dc21d2d6 Mon Sep 17 00:00:00 2001 From: Dave Young Date: Sat, 8 Jan 2011 10:09:13 +0000 Subject: [PATCH] btrfs: mount failure return value fix I happened to pass swap partition as root partition in cmdline, then kernel panic and tell me about "Cannot open root device". It is not correct, in fact it is a fs type mismatch instead of 'no device'. Eventually I found btrfs mounting failed with -EIO, it should be -EINVAL. The logic in init/do_mounts.c: for (p = fs_names; *p; p += strlen(p)+1) { int err = do_mount_root(name, p, flags, root_mount_data); switch (err) { case 0: goto out; case -EACCES: flags |= MS_RDONLY; goto retry; case -EINVAL: continue; } print "Cannot open root device" panic } SO fs type after btrfs will have no chance to mount Here fix the return value as -EINVAL Signed-off-by: Dave Young Signed-off-by: Chris Mason --- fs/btrfs/disk-io.c | 4 +++- fs/btrfs/volumes.c | 8 +++++--- 2 files changed, 8 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index f88eb2c..f9efb68 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1713,8 +1713,10 @@ struct btrfs_root *open_ctree(struct super_block *sb, fs_info, BTRFS_ROOT_TREE_OBJECTID); bh = btrfs_read_dev_super(fs_devices->latest_bdev); - if (!bh) + if (!bh) { + err = -EINVAL; goto fail_iput; + } memcpy(&fs_info->super_copy, bh->b_data, sizeof(fs_info->super_copy)); memcpy(&fs_info->super_for_commit, &fs_info->super_copy, diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 0c7f478..e8be478 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -600,8 +600,10 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, set_blocksize(bdev, 4096); bh = btrfs_read_dev_super(bdev); - if (!bh) + if (!bh) { + ret = -EINVAL; goto error_close; + } disk_super = (struct btrfs_super_block *)bh->b_data; devid = btrfs_stack_device_id(&disk_super->dev_item); @@ -702,7 +704,7 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, goto error_close; bh = btrfs_read_dev_super(bdev); if (!bh) { - ret = -EIO; + ret = -EINVAL; goto error_close; } disk_super = (struct btrfs_super_block *)bh->b_data; @@ -1302,7 +1304,7 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) set_blocksize(bdev, 4096); bh = btrfs_read_dev_super(bdev); if (!bh) { - ret = -EIO; + ret = -EINVAL; goto error_close; } disk_super = (struct btrfs_super_block *)bh->b_data; -- 2.7.4