gfs2: Convert function bh_get to use iomap

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>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 390f34ca3bc87402d9f4736ccb9ecae758b0d6b2..59d727a4ae2cbdc78d8aa42db552e4021f92672e 100644 (file)
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -365,11 +365,12 @@ static void slot_put(struct gfs2_quota_data *qd)
 static int bh_get(struct gfs2_quota_data *qd)
 {
        struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
-       struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
+       struct inode *inode = sdp->sd_qc_inode;
+       struct gfs2_inode *ip = GFS2_I(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 +382,17 @@ 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(inode,
+                              (loff_t)block << inode->i_blkbits,
+                              i_blocksize(inode), &iomap);
        if (error)
                goto fail;
-       error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, 0, &bh);
+       error = -ENOENT;
+       if (iomap.type != IOMAP_MAPPED)
+               goto fail;
+
+       error = gfs2_meta_read(ip->i_gl, iomap.addr >> inode->i_blkbits,
+                              DIO_WAIT, 0, &bh);
        if (error)
                goto fail;
        error = -EIO;