btrfs: ioctl: resize: only show message if size is changed

There is no point to inform the user about size change if there's none.
Update the message to conform to a commonly used format where the path
and devid are printed and also print old and new sizes.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Marcos Paulo de Souza <marcos@mpdesouza.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance message ]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 6ded5e3..0bedb5d 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1710,9 +1710,6 @@ static noinline int btrfs_ioctl_resize(struct file *file,
 
        new_size = round_down(new_size, fs_info->sectorsize);
 
-       btrfs_info_in_rcu(fs_info, "new size for %s is %llu",
-                         rcu_str_deref(device->name), new_size);
-
        if (new_size > old_size) {
                trans = btrfs_start_transaction(root, 0);
                if (IS_ERR(trans)) {
@@ -1725,6 +1722,11 @@ static noinline int btrfs_ioctl_resize(struct file *file,
                ret = btrfs_shrink_device(device, new_size);
        } /* equal, nothing need to do */
 
+       if (ret == 0 && new_size != old_size)
+               btrfs_info_in_rcu(fs_info,
+                       "resize device %s (devid %llu) from %llu to %llu",
+                       rcu_str_deref(device->name), device->devid,
+                       old_size, new_size);
 out_free:
        kfree(vol_args);
 out: