The following commit has been merged in the linux branch: commit 0634857488ec6e28fa22920cd0bee3c2ac07ccfd Author: Christoph Hellwig hch@lst.de Date: Wed Oct 14 09:24:59 2009 -0400

Btrfs: enable discard support

The discard support code in btrfs currently is guarded by ifdefs for BIO_RW_DISCARD, which is never defines as it's the name of an enum memeber. Just remove the useless ifdefs to actually enable the code.

Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Chris Mason chris.mason@oracle.com

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index bf7782f..d4a3528 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -1568,18 +1568,15 @@ static int remove_extent_backref(struct btrfs_trans_handle *trans, return ret; }

-#ifdef BIO_RW_DISCARD static void btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len) { blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL); } -#endif

static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, u64 num_bytes) { -#ifdef BIO_RW_DISCARD int ret; u64 map_length = num_bytes; struct btrfs_multi_bio *multi = NULL; @@ -1606,9 +1603,6 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, }

return ret; -#else - return 0; -#endif }

int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,