ocfs2: Wrap group descriptor reads in a dedicated function.

We have a clean call for validating group descriptors, but every place
that wants the always does a read_block()+validate() call pair.  Create
a toplevel ocfs2_read_group_descriptor() that does the right
thing.  This allows us to leverage the single call point later for
fancier handling.  We also add validation of gd->bg_generation against
the superblock and gd->bg_blkno against the block we thought we read.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 3 insertions, 9 deletions

diff --git a/fs/ocfs2/resize.c b/fs/ocfs2/resize.c
index a2de32a317ad..252baff5eb84 100644
--- a/fs/ocfs2/resize.c
+++ b/fs/ocfs2/resize.c
@@ -330,20 +330,14 @@ int ocfs2_group_extend(struct inode * inode, int new_clusters)
         lgd_blkno = ocfs2_which_cluster_group(main_bm_inode,
                                               first_new_cluster - 1);
 
-        ret = ocfs2_read_block(main_bm_inode, lgd_blkno, &group_bh);
+        ret = ocfs2_read_group_descriptor(main_bm_inode, fe, lgd_blkno,
+                                          &group_bh);
         if (ret < 0) {
                 mlog_errno(ret);
                 goto out_unlock;
         }
-
         group = (struct ocfs2_group_desc *)group_bh->b_data;
 
-        ret = ocfs2_check_group_descriptor(inode->i_sb, fe, group);
-        if (ret) {
-                mlog_errno(ret);
-                goto out_unlock;
-        }
-
         cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
         if (le16_to_cpu(group->bg_bits) / cl_bpc + new_clusters >
                 le16_to_cpu(fe->id2.i_chain.cl_cpg)) {
@@ -400,7 +394,7 @@ static int ocfs2_check_new_group(struct inode *inode,
                 (struct ocfs2_group_desc *)group_bh->b_data;
         u16 cl_bpc = le16_to_cpu(di->id2.i_chain.cl_bpc);
 
-        ret = ocfs2_validate_group_descriptor(inode->i_sb, di, gd, 1);
+        ret = ocfs2_validate_group_descriptor(inode->i_sb, di, group_bh, 1);
         if (ret)
                 goto out;