[XFS] V1 log tweak - fix log record length used when checking for a partial log

record write during log recovery head/tail calculations.

SGI Modid: 2.5.x-xfs:slinx:148895a

fs/xfs/xfs_log_priv.h

@@ -73,6 +73,9 @@ int xlog_btolrbb(int b);
 
 #define XLOG_HEADER_SIZE	512
 
+#define XLOG_REC_SHIFT(log) \
+	BTOBB(1 << (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? \
+	 XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT))
 #define XLOG_TOTAL_REC_SHIFT(log) \
 	BTOBB(XLOG_MAX_ICLOGS << (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? \
 	 XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT))

fs/xfs/xfs_log_recover.c

@@ -675,7 +675,7 @@ xlog_find_head(xlog_t  *log,
      * Now we need to make sure head_blk is not pointing to a block in
      * the middle of a log record.
      */
-    num_scan_bblks = BTOBB(XLOG_MAX_RECORD_BSIZE);
+    num_scan_bblks = XLOG_REC_SHIFT(log);
     if (head_blk >= num_scan_bblks) {
 	start_blk = head_blk - num_scan_bblks;  /* don't read head_blk */