James/linux-scsi,
The following patch for megaraid_sas fixes the fastpath code decision
logic to use fpRead/WriteCapable, fpRead/WriteAcrossStripe flags
instead of the old logic. This fixes a bug where fastpath writes
could be sent to a read only LD.
Signed-off-by: Adam Radford <aradford@xxxxxxxxx>
diff -Naur scsi-misc-2.6/drivers/scsi/megaraid/megaraid_sas_fp.c
scsi-misc-2.6.new/drivers/scsi/megaraid/megaraid_sas_fp.c
--- scsi-misc-2.6/drivers/scsi/megaraid/megaraid_sas_fp.c 2012-03-19
17:39:08.313986900 -0700
+++ scsi-misc-2.6.new/drivers/scsi/megaraid/megaraid_sas_fp.c 2012-03-19
17:50:22.484862892 -0700
@@ -362,15 +362,20 @@
/* assume this IO needs the full row - we'll adjust if not true */
regSize = stripSize;
- /* If IO spans more than 1 strip, fp is not possible
- FP is not possible for writes on non-0 raid levels
- FP is not possible if LD is not capable */
- if (num_strips > 1 || (!isRead && raid->level != 0) ||
- !raid->capability.fpCapable) {
+ /* Check if we can send this I/O via FastPath */
+ if (raid->capability.fpCapable) {
+ if (isRead)
+ io_info->fpOkForIo = (raid->capability.fpReadCapable &&
+ ((num_strips == 1) ||
+ raid->capability.
+ fpReadAcrossStripe));
+ else
+ io_info->fpOkForIo = (raid->capability.fpWriteCapable &&
+ ((num_strips == 1) ||
+ raid->capability.
+ fpWriteAcrossStripe));
+ } else
io_info->fpOkForIo = FALSE;
- } else {
- io_info->fpOkForIo = TRUE;
- }
if (numRows == 1) {
/* single-strip IOs can always lock only the data needed */
Attachment:
megaraid_sas.patch2
Description: Binary data
