[Cluster-devel] [PATCH] gfs2: Convert function bh_get to use iomap

[Bob Peterson <rpeterso@redhat.com>]

Before this patch, function bh_get used block_map to figure out the
block it needed to read in from the quota_change file. This patch
changes it to use iomap directly to make it more efficient.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
---
 fs/gfs2/quota.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index dc77080a82bb..91bc3affe460 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -368,8 +368,8 @@ static int bh_get(struct gfs2_quota_data *qd)
 	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 	unsigned int block, offset;
 	struct buffer_head *bh;
+	struct iomap iomap = { };
 	int error;
-	struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 
 	mutex_lock(&sdp->sd_quota_mutex);
 
@@ -381,11 +381,18 @@ static int bh_get(struct gfs2_quota_data *qd)
 	block = qd->qd_slot / sdp->sd_qc_per_block;
 	offset = qd->qd_slot % sdp->sd_qc_per_block;
 
-	bh_map.b_size = BIT(ip->i_inode.i_blkbits);
-	error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
+	error = gfs2_iomap_get(sdp->sd_qc_inode,
+			       (loff_t)block << sdp->sd_qc_inode->i_blkbits,
+			       sdp->sd_sb.sb_bsize, &iomap);
 	if (error)
 		goto fail;
-	error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, 0, &bh);
+	if (iomap.addr == IOMAP_NULL_ADDR) {
+		error = -ENOENT;
+		goto fail;
+	}
+
+	error = gfs2_meta_read(ip->i_gl, iomap.addr >> sdp->sd_qc_inode->i_blkbits,
+			       DIO_WAIT, 0, &bh);
 	if (error)
 		goto fail;
 	error = -EIO;
-- 
2.34.1