/* Warning: even if it returns true, this does *not* guarantee that
* the block is stored in our inode metadata cache.
*
* This can be called under lock_buffer()
*/
int ocfs2_buffer_uptodate(struct inode *inode,
struct buffer_head *bh)
{
/* Doesn't matter if the bh is in our cache or not -- if it's
* not marked uptodate then we know it can't have correct
* data. */
if (!buffer_uptodate(bh))
return 0;
/* OCFS2 does not allow multiple nodes to be changing the same
* block at the same time. */
if (buffer_jbd(bh))
return 1;
/* Ok, locally the buffer is marked as up to date, now search
* our cache to see if we can trust that. */
return ocfs2_buffer_cached(OCFS2_I(inode), bh);
}
/*
* Determine whether a buffer is currently out on a read-ahead request.
* ip_io_sem should be held to serialize submitters with the logic here.
*/
int ocfs2_buffer_read_ahead(struct inode *inode,
struct buffer_head *bh)
{
return buffer_locked(bh) && ocfs2_buffer_cached(OCFS2_I(inode), bh);
}
/*
* Determine whether a buffer is currently out on a read-ahead request.
* ci_io_sem should be held to serialize submitters with the logic here.
*/
int ocfs2_buffer_read_ahead(struct ocfs2_caching_info *ci,
struct buffer_head *bh)
{
return buffer_locked(bh) && ocfs2_buffer_cached(ci, bh);
}