GFS2: fallocate support
This patch adds support for fallocate to gfs2. Since the gfs2 does not support
uninitialized data blocks, it must write out zeros to all the blocks. However,
since it does not need to lock any pages to read from, gfs2 can write out the
zero blocks much more efficiently. On a moderately full filesystem, fallocate
works around 5 times faster on average. The fallocate call also allows gfs2 to
add blocks to the file without changing the filesize, which will make it
possible for gfs2 to preallocate space for the rindex file, so that gfs2 can
grow a completely full filesystem.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/trans.h b/fs/gfs2/trans.h
index edf9d4b..b849eb7 100644
--- a/fs/gfs2/trans.h
+++ b/fs/gfs2/trans.h
@@ -20,6 +20,7 @@
#define RES_JDATA 1
#define RES_DATA 1
#define RES_LEAF 1
+#define RES_RG_HDR 1
#define RES_RG_BIT 2
#define RES_EATTR 1
#define RES_STATFS 1