path: root/fs/ioctl.c
diff options
authorJosef Bacik <josef@redhat.com>2011-02-01 15:52:47 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-02-02 16:03:20 -0800
commitd54cdc8ca7aabc69e145a62155855db42b04ed0b (patch)
treee184aed1d4c05e1df482dbf4b669723e31a841e1 /fs/ioctl.c
parent3cd90ea42f2c15f928b70ed66f6d8ed0a8e7aadd (diff)
fs: make block fiemap mapping length at least blocksize long
Some filesystems don't deal well with being asked to map less than blocksize blocks (GFS2 for example). Since we are always mapping at least blocksize sections anyway, just make sure len is at least as big as a blocksize so we don't trip up any filesystems. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/ioctl.c')
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/ioctl.c b/fs/ioctl.c
index a59635e295f..1eebeb72b20 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -273,6 +273,13 @@ int __generic_block_fiemap(struct inode *inode,
len = isize;
+ /*
+ * Some filesystems can't deal with being asked to map less than
+ * blocksize, so make sure our len is at least block length.
+ */
+ if (logical_to_blk(inode, len) == 0)
+ len = blk_to_logical(inode, 1);
start_blk = logical_to_blk(inode, start);
last_blk = logical_to_blk(inode, start + len - 1);