ocfs2: Wrap inode block reads in a dedicated function.

The ocfs2 code currently reads inodes off disk with a simple
ocfs2_read_block() call.  Each place that does this has a different set
of sanity checks it performs.  Some check only the signature.  A couple
validate the block number (the block read vs di->i_blkno).  A couple
others check for VALID_FL.  Only one place validates i_fs_generation.  A
couple check nothing.  Even when an error is found, they don't all do
the same thing.

We wrap inode reading into ocfs2_read_inode_block().  This will validate
all the above fields, going readonly if they are invalid (they never
should be).  ocfs2_read_inode_block_full() is provided for the places
that want to pass read_block flags.  Every caller is passing a struct
inode with a valid ip_blkno, so we don't need a separate blkno argument
either.

We will remove the validation checks from the rest of the code in a
later commit, as they are no longer necessary.

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

1 files changed, 2 insertions, 9 deletions

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index c22543b3342..e219f8b546a 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -68,20 +68,13 @@ static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
                 goto bail;
         }
 
-        status = ocfs2_read_block(inode, OCFS2_I(inode)->ip_blkno, &bh);
+        status = ocfs2_read_inode_block(inode, &bh);
         if (status < 0) {
                 mlog_errno(status);
                 goto bail;
         }
         fe = (struct ocfs2_dinode *) bh->b_data;
 
-        if (!OCFS2_IS_VALID_DINODE(fe)) {
-                mlog(ML_ERROR, "Invalid dinode #%llu: signature = %.*s\n",
-                     (unsigned long long)le64_to_cpu(fe->i_blkno), 7,
-                     fe->i_signature);
-                goto bail;
-        }
-
         if ((u64)iblock >= ocfs2_clusters_to_blocks(inode->i_sb,
                                                     le32_to_cpu(fe->i_clusters))) {
                 mlog(ML_ERROR, "block offset is outside the allocated size: "
@@ -262,7 +255,7 @@ static int ocfs2_readpage_inline(struct inode *inode, struct page *page)
         BUG_ON(!PageLocked(page));
         BUG_ON(!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL));
 
-        ret = ocfs2_read_block(inode, OCFS2_I(inode)->ip_blkno, &di_bh);
+        ret = ocfs2_read_inode_block(inode, &di_bh);
         if (ret) {
                 mlog_errno(ret);
                 goto out;