[GFS2] Add extent allocation to block allocator

Rather than having to allocate a single block at a time, this patch
allows the block allocator to allocate an extent. Since there is
no difference (so far as the block allocator is concerned) between
data blocks and indirect blocks, it is posible to allocate a single
extent and for the caller to unrevoke just the blocks required
for indirect blocks.

Currently the only bit of GFS2 to make use of this feature is the
build height function. The intention is that gfs2_block_map will
be changed to make use of this feature in future patches.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/fs/gfs2/eattr.c b/fs/gfs2/eattr.c
index f9f63bc21cd2..0e79cd543496 100644
--- a/fs/gfs2/eattr.c
+++ b/fs/gfs2/eattr.c
@@ -582,9 +582,10 @@ static int ea_alloc_blk(struct gfs2_inode *ip, struct buffer_head **bhp)
 {
 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 	struct gfs2_ea_header *ea;
+	unsigned int n = 1;
 	u64 block;
 
-	block = gfs2_alloc_block(ip);
+	block = gfs2_alloc_block(ip, &n);
 	gfs2_trans_add_unrevoke(sdp, block, 1);
 	*bhp = gfs2_meta_new(ip->i_gl, block);
 	gfs2_trans_add_bh(ip->i_gl, *bhp, 1);
@@ -642,8 +643,9 @@ static int ea_write(struct gfs2_inode *ip, struct gfs2_ea_header *ea,
 			struct buffer_head *bh;
 			u64 block;
 			int mh_size = sizeof(struct gfs2_meta_header);
+			unsigned int n = 1;
 
-			block = gfs2_alloc_block(ip);
+			block = gfs2_alloc_block(ip, &n);
 			gfs2_trans_add_unrevoke(sdp, block, 1);
 			bh = gfs2_meta_new(ip->i_gl, block);
 			gfs2_trans_add_bh(ip->i_gl, bh, 1);
@@ -966,8 +968,8 @@ static int ea_set_block(struct gfs2_inode *ip, struct gfs2_ea_request *er,
 		gfs2_trans_add_bh(ip->i_gl, indbh, 1);
 	} else {
 		u64 blk;
-
-		blk = gfs2_alloc_block(ip);
+		unsigned int n = 1;
+		blk = gfs2_alloc_block(ip, &n);
 		gfs2_trans_add_unrevoke(sdp, blk, 1);
 		indbh = gfs2_meta_new(ip->i_gl, blk);
 		gfs2_trans_add_bh(ip->i_gl, indbh, 1);