[PATCH] Btrfs: fix missing s_id setting

[Tsutomu Itoh]

When fs_devices->latest_bdev is deleted or is replaced, sb->s_id has
not been updated.
As a result, the deleted device name is displayed by btrfs_printk.

[before fix]
 # btrfs dev del /dev/sdc4 /mnt2
 # btrfs dev add /dev/sdb6 /mnt2

 [  217.458249] BTRFS info (device sdc4): found 1 extents
 [  217.695798] BTRFS info (device sdc4): disk deleted /dev/sdc4
 [  217.941284] BTRFS info (device sdc4): disk added /dev/sdb6

[after fix]
 # btrfs dev del /dev/sdc4 /mnt2
 # btrfs dev add /dev/sdb6 /mnt2

 [   83.835072] BTRFS info (device sdc4): found 1 extents
 [   84.080617] BTRFS info (device sdc3): disk deleted /dev/sdc4
 [   84.401951] BTRFS info (device sdc3): disk added /dev/sdb6

Signed-off-by: Tsutomu Itoh <t-i...@jp.fujitsu.com>
---
 fs/btrfs/dev-replace.c |  5 ++++-
 fs/btrfs/volumes.c     | 11 +++++++++--
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index a1d6652..11c4198 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -560,8 +560,11 @@ static int btrfs_dev_replace_finishing(struct 
btrfs_fs_info *fs_info,
        tgt_device->commit_bytes_used = src_device->bytes_used;
        if (fs_info->sb->s_bdev == src_device->bdev)
                fs_info->sb->s_bdev = tgt_device->bdev;
-       if (fs_info->fs_devices->latest_bdev == src_device->bdev)
+       if (fs_info->fs_devices->latest_bdev == src_device->bdev) {
                fs_info->fs_devices->latest_bdev = tgt_device->bdev;
+               snprintf(fs_info->sb->s_id, sizeof(fs_info->sb->s_id), "%pg",
+                        tgt_device->bdev);
+       }
        list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
        fs_info->fs_devices->rw_devices++;
 
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index e2b54d5..a471385 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1846,8 +1846,12 @@ int btrfs_rm_device(struct btrfs_root *root, char 
*device_path)
                                 struct btrfs_device, dev_list);
        if (device->bdev == root->fs_info->sb->s_bdev)
                root->fs_info->sb->s_bdev = next_device->bdev;
-       if (device->bdev == root->fs_info->fs_devices->latest_bdev)
+       if (device->bdev == root->fs_info->fs_devices->latest_bdev) {
                root->fs_info->fs_devices->latest_bdev = next_device->bdev;
+               snprintf(root->fs_info->sb->s_id,
+                        sizeof(root->fs_info->sb->s_id), "%pg",
+                        next_device->bdev);
+       }
 
        if (device->bdev) {
                device->fs_devices->open_devices--;
@@ -2034,8 +2038,11 @@ void btrfs_destroy_dev_replace_tgtdev(struct 
btrfs_fs_info *fs_info,
                                 struct btrfs_device, dev_list);
        if (tgtdev->bdev == fs_info->sb->s_bdev)
                fs_info->sb->s_bdev = next_device->bdev;
-       if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
+       if (tgtdev->bdev == fs_info->fs_devices->latest_bdev) {
                fs_info->fs_devices->latest_bdev = next_device->bdev;
+               snprintf(fs_info->sb->s_id, sizeof(fs_info->sb->s_id), "%pg",
+                        next_device->bdev);
+       }
        list_del_rcu(&tgtdev->dev_list);
 
        call_rcu(&tgtdev->rcu, free_device);
-- 
2.6.4


--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html