Commit 98b69b12 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Darrick J. Wong
Browse files

xfs: refactor xlog_recover_buffer_pass1 



Split out a xlog_add_buffer_cancelled helper which does the low-level
manipulation of the buffer cancelation table, and in that helper call
xlog_find_buffer_cancelled instead of open coding it.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
parent f15ab3f6

fs/xfs/xfs_log_recover.c

+55 −59
Original line number Diff line number Diff line
@@ -1913,65 +1913,6 @@ xlog_recover_reorder_trans( 
	return error;

}



/*

 * Build up the table of buf cancel records so that we don't replay

 * cancelled data in the second pass.  For buffer records that are

 * not cancel records, there is nothing to do here so we just return.

 *

 * If we get a cancel record which is already in the table, this indicates

 * that the buffer was cancelled multiple times.  In order to ensure

 * that during pass 2 we keep the record in the table until we reach its

 * last occurrence in the log, we keep a reference count in the cancel

 * record in the table to tell us how many times we expect to see this

 * record during the second pass.

 */

STATIC int

xlog_recover_buffer_pass1(

	struct xlog			*log,

	struct xlog_recover_item	*item)

{

	xfs_buf_log_format_t	*buf_f = item->ri_buf[0].i_addr;

	struct list_head	*bucket;

	struct xfs_buf_cancel	*bcp;



	if (!xfs_buf_log_check_iovec(&item->ri_buf[0])) {

		xfs_err(log->l_mp, "bad buffer log item size (%d)",

				item->ri_buf[0].i_len);

		return -EFSCORRUPTED;

	}



	/*

	 * If this isn't a cancel buffer item, then just return.

	 */

	if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) {

		trace_xfs_log_recover_buf_not_cancel(log, buf_f);

		return 0;

	}



	/*

	 * Insert an xfs_buf_cancel record into the hash table of them.

	 * If there is already an identical record, bump its reference count.

	 */

	bucket = XLOG_BUF_CANCEL_BUCKET(log, buf_f->blf_blkno);

	list_for_each_entry(bcp, bucket, bc_list) {

		if (bcp->bc_blkno == buf_f->blf_blkno &&

		    bcp->bc_len == buf_f->blf_len) {

			bcp->bc_refcount++;

			trace_xfs_log_recover_buf_cancel_ref_inc(log, buf_f);

			return 0;

		}

	}



	bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), 0);

	bcp->bc_blkno = buf_f->blf_blkno;

	bcp->bc_len = buf_f->blf_len;

	bcp->bc_refcount = 1;

	list_add_tail(&bcp->bc_list, bucket);



	trace_xfs_log_recover_buf_cancel_add(log, buf_f);

	return 0;

}



static struct xfs_buf_cancel *

xlog_find_buffer_cancelled(

	struct xlog		*log,
@@ -1993,6 +1934,35 @@ xlog_find_buffer_cancelled( 
	return NULL;

}



static bool

xlog_add_buffer_cancelled(

	struct xlog		*log,

	xfs_daddr_t		blkno,

	uint			len)

{

	struct xfs_buf_cancel	*bcp;



	/*

	 * If we find an existing cancel record, this indicates that the buffer

	 * was cancelled multiple times.  To ensure that during pass 2 we keep

	 * the record in the table until we reach its last occurrence in the

	 * log, a reference count is kept to tell how many times we expect to

	 * see this record during the second pass.

	 */

	bcp = xlog_find_buffer_cancelled(log, blkno, len);

	if (bcp) {

		bcp->bc_refcount++;

		return false;

	}



	bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), 0);

	bcp->bc_blkno = blkno;

	bcp->bc_len = len;

	bcp->bc_refcount = 1;

	list_add_tail(&bcp->bc_list, XLOG_BUF_CANCEL_BUCKET(log, blkno));

	return true;

}



/*

 * Check if there is and entry for blkno, len in the buffer cancel record table.

 */
@@ -2045,6 +2015,32 @@ xlog_buf_readahead( 
		xfs_buf_readahead(log->l_mp->m_ddev_targp, blkno, len, ops);

}



/*

 * Build up the table of buf cancel records so that we don't replay cancelled

 * data in the second pass.

 */

static int

xlog_recover_buffer_pass1(

	struct xlog			*log,

	struct xlog_recover_item	*item)

{

	struct xfs_buf_log_format	*bf = item->ri_buf[0].i_addr;



	if (!xfs_buf_log_check_iovec(&item->ri_buf[0])) {

		xfs_err(log->l_mp, "bad buffer log item size (%d)",

				item->ri_buf[0].i_len);

		return -EFSCORRUPTED;

	}



	if (!(bf->blf_flags & XFS_BLF_CANCEL))

		trace_xfs_log_recover_buf_not_cancel(log, bf);

	else if (xlog_add_buffer_cancelled(log, bf->blf_blkno, bf->blf_len))

		trace_xfs_log_recover_buf_cancel_add(log, bf);

	else

		trace_xfs_log_recover_buf_cancel_ref_inc(log, bf);

	return 0;

}



/*

 * Perform recovery for a buffer full of inodes.  In these buffers, the only

 * data which should be recovered is that which corresponds to the