+/*
+ * Read at an offset into the buffer. Returns with the buffer in it's original
+ * state regardless of the result of the read.
+ */
+STATIC int
+xlog_bread_offset(
+ xlog_t *log,
+ xfs_daddr_t blk_no, /* block to read from */
+ int nbblks, /* blocks to read */
+ xfs_buf_t *bp,
+ xfs_caddr_t offset)
+{
+ xfs_caddr_t orig_offset = XFS_BUF_PTR(bp);
+ int orig_len = bp->b_buffer_length;
+ int error, error2;
+
+ error = XFS_BUF_SET_PTR(bp, offset, BBTOB(nbblks));
+ if (error)
+ return error;
+
+ error = xlog_bread_noalign(log, blk_no, nbblks, bp);
+
+ /* must reset buffer pointer even on error */
+ error2 = XFS_BUF_SET_PTR(bp, orig_offset, orig_len);
+ if (error)
+ return error;
+ return error2;
+}
+