[GFS2] Move part of gfs2_block_map into a separate function

This is required to enable future changes to the block
mapping code.

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

1 files changed, 36 insertions, 21 deletions

diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index e84e3845a394..08d1be492ef7 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -384,6 +384,35 @@ static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh,
         return 0;
 }
 
+static int lookup_metapath(struct inode *inode, struct metapath *mp,
+                           int create, int *new, u64 *dblock,
+                           struct buffer_head **dibh, struct buffer_head **bh)
+{
+        struct gfs2_inode *ip = GFS2_I(inode);
+        unsigned int end_of_metadata = ip->i_height - 1;
+        unsigned int x;
+        int ret = gfs2_meta_inode_buffer(ip, bh);
+        if (ret)
+                return ret;
+
+        *dibh = *bh;
+        get_bh(*dibh);
+
+        for (x = 0; x < end_of_metadata; x++) {
+                lookup_block(ip, *bh, x, mp, create, new, dblock);
+                brelse(*bh);
+                *bh = NULL;
+                if (!dblock)
+                        return 0;
+
+                ret = gfs2_meta_indirect_buffer(ip, x+1, *dblock, *new, bh);
+                if (ret)
+                        return ret;
+        }
+
+        return lookup_block(ip, *bh, end_of_metadata, mp, create, new, dblock);
+}
+
 static inline void bmap_lock(struct inode *inode, int create)
 {
         struct gfs2_inode *ip = GFS2_I(inode);
@@ -419,10 +448,8 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
 {
         struct gfs2_inode *ip = GFS2_I(inode);
         struct gfs2_sbd *sdp = GFS2_SB(inode);
-        struct buffer_head *bh;
         unsigned int bsize = sdp->sd_sb.sb_bsize;
-        unsigned int end_of_metadata;
-        unsigned int x;
+        struct buffer_head *bh = NULL;
         int error = 0;
         int new = 0;
         u64 dblock = 0;
@@ -459,25 +486,11 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
         }
 
         find_metapath(ip, lblock, &mp);
-        end_of_metadata = ip->i_height - 1;
-        error = gfs2_meta_inode_buffer(ip, &bh);
-        if (error)
+        error = lookup_metapath(inode, &mp, create, &new, &dblock, &dibh, &bh);
+        if (error < 0)
                 goto out_fail;
-        dibh = bh;
-        get_bh(dibh);
-
-        for (x = 0; x < end_of_metadata; x++) {
-                lookup_block(ip, bh, x, &mp, create, &new, &dblock);
-                brelse(bh);
-                if (!dblock)
-                        goto out_ok;
+        boundary = error;
 
-                error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh);
-                if (error)
-                        goto out_fail;
-        }
-
-        boundary = lookup_block(ip, bh, end_of_metadata, &mp, create, &new, &dblock);
         if (dblock) {
                 map_bh(bh_map, inode->i_sb, dblock);
                 if (boundary)
@@ -489,6 +502,7 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
                         goto out_brelse;
                 }
                 while(--maxlen && !buffer_boundary(bh_map)) {
+                        unsigned int end_of_metadata = ip->i_height - 1;
                         u64 eblock;
 
                         mp.mp_list[end_of_metadata]++;
@@ -501,7 +515,8 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
                 }
         }
 out_brelse:
-        brelse(bh);
+        if (bh)
+                brelse(bh);
 out_ok:
         error = 0;
 out_fail: