summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLukas Czerner <lczerner@redhat.com>2011-02-23 20:42:32 +0300
committerTheodore Ts'o <tytso@mit.edu>2011-02-23 20:42:32 +0300
commit4143179218960a70d821a425e3c23ce44aa93dee (patch)
tree8f7aa98378a979ebfa323165ae985d7d5b39a24c
parent0b75a840120b1e647e32342e9cc46631410088d5 (diff)
downloadlinux-4143179218960a70d821a425e3c23ce44aa93dee.tar.xz
ext4: check if device support discard in FITRIM ioctl
For a device that does not support discard, the FITRIM ioctl returns -EOPNOTSUPP when blkdev_issue_discard() returns this error code, which is how the user is informed that the device does not support discard. If there are no suitable free extents to be trimmed, then FITRIM will return success even though the device does not support discard, which could confuse the user. So check explicitly if the device supports discard and return an error code at the beginning of the FITRIM ioctl processing. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
-rw-r--r--fs/ext4/ioctl.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index eb3bc2fe647e..25ba7c79d289 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -334,12 +334,16 @@ mext_out:
case FITRIM:
{
struct super_block *sb = inode->i_sb;
+ struct request_queue *q = bdev_get_queue(sb->s_bdev);
struct fstrim_range range;
int ret = 0;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
+ if (!blk_queue_discard(q))
+ return -EOPNOTSUPP;
+
if (copy_from_user(&range, (struct fstrim_range *)arg,
sizeof(range)))
return -EFAULT;