This is a note to let you know that I've just added the patch titled
SCSI: sd: Update WRITE SAME heuristics
to the 3.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-sd-update-write-same-heuristics.patch
and it can be found in the queue-3.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 66c28f97120e8a621afd5aa7a31c4b85c547d33d Mon Sep 17 00:00:00 2001
From: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>
Date: Thu, 6 Jun 2013 22:15:55 -0400
Subject: SCSI: sd: Update WRITE SAME heuristics
From: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>
commit 66c28f97120e8a621afd5aa7a31c4b85c547d33d upstream.
SATA drives located behind a SAS controller would incorrectly receive
WRITE SAME commands. Tweak the heuristics so that:
- If REPORT SUPPORTED OPERATION CODES is provided we will use that to
choose between WRITE SAME(16), WRITE SAME(10) and disabled. This also
fixes an issue with the old code which would issue WRITE SAME(10)
despite the command not being whitelisted in REPORT SUPPORTED
OPERATION CODES.
- If REPORT SUPPORTED OPERATION CODES is not provided we will fall back
to WRITE SAME(10) unless the device has an ATA Information VPD page.
The assumption is that a SATL which is smart enough to implement
WRITE SAME would also provide REPORT SUPPORTED OPERATION CODES.
To facilitate the new heuristics scsi_report_opcode() has been modified
to so we can distinguish between "operation not supported" and "RSOC not
supported".
Reported-by: H. Peter Anvin <hpa@xxxxxxxxx>
Tested-by: Bernd Schubert <bernd.schubert@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: James Bottomley <JBottomley@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/scsi.c | 8 ++++----
drivers/scsi/sd.c | 46 ++++++++++++++++++++++++++++++++--------------
drivers/scsi/sd.h | 1 +
3 files changed, 37 insertions(+), 18 deletions(-)
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -1070,8 +1070,8 @@ EXPORT_SYMBOL_GPL(scsi_get_vpd_page);
* @opcode: opcode for command to look up
*
* Uses the REPORT SUPPORTED OPERATION CODES to look up the given
- * opcode. Returns 0 if RSOC fails or if the command opcode is
- * unsupported. Returns 1 if the device claims to support the command.
+ * opcode. Returns -EINVAL if RSOC fails, 0 if the command opcode is
+ * unsupported and 1 if the device claims to support the command.
*/
int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
unsigned int len, unsigned char opcode)
@@ -1081,7 +1081,7 @@ int scsi_report_opcode(struct scsi_devic
int result;
if (sdev->no_report_opcodes || sdev->scsi_level < SCSI_SPC_3)
- return 0;
+ return -EINVAL;
memset(cmd, 0, 16);
cmd[0] = MAINTENANCE_IN;
@@ -1097,7 +1097,7 @@ int scsi_report_opcode(struct scsi_devic
if (result && scsi_sense_valid(&sshdr) &&
sshdr.sense_key == ILLEGAL_REQUEST &&
(sshdr.asc == 0x20 || sshdr.asc == 0x24) && sshdr.ascq == 0x00)
- return 0;
+ return -EINVAL;
if ((buffer[1] & 3) == 3) /* Command supported */
return 1;
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -442,8 +442,10 @@ sd_store_write_same_blocks(struct device
if (max == 0)
sdp->no_write_same = 1;
- else if (max <= SD_MAX_WS16_BLOCKS)
+ else if (max <= SD_MAX_WS16_BLOCKS) {
+ sdp->no_write_same = 0;
sdkp->max_ws_blocks = max;
+ }
sd_config_write_same(sdkp);
@@ -740,7 +742,6 @@ static void sd_config_write_same(struct
{
struct request_queue *q = sdkp->disk->queue;
unsigned int logical_block_size = sdkp->device->sector_size;
- unsigned int blocks = 0;
if (sdkp->device->no_write_same) {
sdkp->max_ws_blocks = 0;
@@ -752,18 +753,20 @@ static void sd_config_write_same(struct
* blocks per I/O unless the device explicitly advertises a
* bigger limit.
*/
- if (sdkp->max_ws_blocks == 0)
- sdkp->max_ws_blocks = SD_MAX_WS10_BLOCKS;
-
- if (sdkp->ws16 || sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS)
- blocks = min_not_zero(sdkp->max_ws_blocks,
- (u32)SD_MAX_WS16_BLOCKS);
- else
- blocks = min_not_zero(sdkp->max_ws_blocks,
- (u32)SD_MAX_WS10_BLOCKS);
+ if (sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS)
+ sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
+ (u32)SD_MAX_WS16_BLOCKS);
+ else if (sdkp->ws16 || sdkp->ws10 || sdkp->device->no_report_opcodes)
+ sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
+ (u32)SD_MAX_WS10_BLOCKS);
+ else {
+ sdkp->device->no_write_same = 1;
+ sdkp->max_ws_blocks = 0;
+ }
out:
- blk_queue_max_write_same_sectors(q, blocks * (logical_block_size >> 9));
+ blk_queue_max_write_same_sectors(q, sdkp->max_ws_blocks *
+ (logical_block_size >> 9));
}
/**
@@ -2635,9 +2638,24 @@ static void sd_read_block_provisioning(s
static void sd_read_write_same(struct scsi_disk *sdkp, unsigned char *buffer)
{
- if (scsi_report_opcode(sdkp->device, buffer, SD_BUF_SIZE,
- WRITE_SAME_16))
+ struct scsi_device *sdev = sdkp->device;
+
+ if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, INQUIRY) < 0) {
+ sdev->no_report_opcodes = 1;
+
+ /* Disable WRITE SAME if REPORT SUPPORTED OPERATION
+ * CODES is unsupported and the device has an ATA
+ * Information VPD page (SAT).
+ */
+ if (!scsi_get_vpd_page(sdev, 0x89, buffer, SD_BUF_SIZE))
+ sdev->no_write_same = 1;
+ }
+
+ if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME_16) == 1)
sdkp->ws16 = 1;
+
+ if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME) == 1)
+ sdkp->ws10 = 1;
}
static int sd_try_extended_inquiry(struct scsi_device *sdp)
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -84,6 +84,7 @@ struct scsi_disk {
unsigned lbpws : 1;
unsigned lbpws10 : 1;
unsigned lbpvpd : 1;
+ unsigned ws10 : 1;
unsigned ws16 : 1;
};
#define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
Patches currently in stable-queue which might be from martin.petersen@xxxxxxxxxx are
queue-3.10/scsi-sd-update-write-same-heuristics.patch
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