ocfs2: Use metadata-specific ocfs2_journal_access_*() functions.

The per-metadata-type ocfs2_journal_access_*() functions hook up jbd2
commit triggers and allow us to compute metadata ecc right before the
buffers are written out.  This commit provides ecc for inodes, extent
blocks, group descriptors, and quota blocks.  It is not safe to use
extened attributes and metaecc at the same time yet.

The ocfs2_extent_tree and ocfs2_path abstractions in alloc.c both hide
the type of block at their root.  Before, it didn't matter, but now the
root block must use the appropriate ocfs2_journal_access_*() function.
To keep this abstract, the structures now have a pointer to the matching
journal_access function and a wrapper call to call it.

A few places use naked ocfs2_write_block() calls instead of adding the
blocks to the journal.  We make sure to calculate their checksum and ecc
before the write.

Since we pass around the journal_access functions.  Let's typedef them
in ocfs2.h.

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

1 files changed, 4 insertions, 0 deletions

diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 2bb389f..bad87d0 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -339,6 +339,10 @@ struct ocfs2_super
 
 #define OCFS2_SB(sb)	    ((struct ocfs2_super *)(sb)->s_fs_info)
 
+/* Useful typedef for passing around journal access functions */
+typedef int (*ocfs2_journal_access_func)(handle_t *handle, struct inode *inode,
+					 struct buffer_head *bh, int type);
+
 static inline int ocfs2_should_order_data(struct inode *inode)
 {
 	if (!S_ISREG(inode->i_mode))