[PATCH] s390: don't pad cdl blocks for write requests

The first blocks on a cdl formatted dasd device are smaller than the blocksize of the device. Read requests are padded with a 'e5' pattern. Write requests should not pad the (user) buffer with 'e5' because a write request is not allowed to modify the buffer. Signed-off-by: Martin Schwidefsky <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
josf · May 1, 2005 · ec5883a · ec5883a
1 parent 6ed93c8
commit ec5883a
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
@@ -7,7 +7,7 @@
  * Bugreports.to..: <[email protected]>
  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
  *
- * $Revision: 1.69 $
+ * $Revision: 1.71 $
  */
 
 #include <linux/config.h>
@@ -1101,7 +1101,8 @@ dasd_eckd_build_cp(struct dasd_device * device, struct request *req)
 				if (dasd_eckd_cdl_special(blk_per_trk, recid)){
 					rcmd |= 0x8;
 					count = dasd_eckd_cdl_reclen(recid);
-					if (count < blksize)
+					if (count < blksize &&
+					    rq_data_dir(req) == READ)
 						memset(dst + count, 0xe5,
 						       blksize - count);
 				}