From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josef Bacik Subject: [PATCH] Btrfs: add a comment explaining what btrfs_cont_expand does Date: Fri, 4 Mar 2011 15:47:46 -0500 Message-ID: <1299271666-5952-1-git-send-email-josef@redhat.com> To: linux-btrfs@vger.kernel.org Return-path: List-ID: Everytime I have to deal with btrfs_cont_expand I stare at it for 20 minutes trying to remember what exactly it does and why the hell we need it. So add a comment to save future-Josef some time. Thanks, Signed-off-by: Josef Bacik --- fs/btrfs/inode.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index c19d2df..a650b7c 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3557,6 +3557,12 @@ out: return ret; } +/* + * This function puts in dummy file extents for the area we're creating a hole + * for. So if we are truncating this file to a larger size we need to insert + * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for + * the range between oldsize and size + */ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size) { struct btrfs_trans_handle *trans; -- 1.7.2.3