4.4-stable review patch. If anyone has any objections, please let me know.
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From: Jeff Mahoney jeffm@suse.com
commit 0be88e367fd8fbdb45257615d691f4675dda062f upstream.
We check whether any device the file system is using supports discard in the ioctl call, but then we attempt to trim free extents on every device regardless of whether discard is supported. Due to the way we mask off EOPNOTSUPP, we can end up issuing the trim operations on each free range on devices that don't support it, just wasting time.
Fixes: 499f377f49f08 ("btrfs: iterate over unused chunk space in FITRIM") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Jeff Mahoney jeffm@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/extent-tree.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -10629,6 +10629,10 @@ static int btrfs_trim_free_extents(struc
*trimmed = 0;
+ /* Discard not supported = nothing to do. */ + if (!blk_queue_discard(bdev_get_queue(device->bdev))) + return 0; + /* Not writeable = nothing to do. */ if (!device->writeable) return 0;