path: root/drivers/ata
diff options
authorMartin K. Petersen <martin.petersen@oracle.com>2013-10-23 06:25:40 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-12-11 22:36:28 -0800
commit8562d028775e7c88fc7fa8c5deaa791392892778 (patch)
tree8b40e1f29bf66978ef17364bc583f74d3a5fc614 /drivers/ata
parent5e43e33a63d72c6bd30f9fa14a9e82ffb58be422 (diff)
SCSI: Disable WRITE SAME for RAID and virtual host adapter drivers
commit 54b2b50c20a61b51199bedb6e5d2f8ec2568fb43 upstream. Some host adapters do not pass commands through to the target disk directly. Instead they provide an emulated target which may or may not accurately report its capabilities. In some cases the physical device characteristics are reported even when the host adapter is processing commands on the device's behalf. This can lead to adapter firmware hangs or excessive I/O errors. This patch disables WRITE SAME for devices connected to host adapters that provide an emulated target. Driver writers can disable WRITE SAME by setting the no_write_same flag in the host adapter template. [jejb: fix up rejections due to eh_deadline patch] Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/ata')
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 0101af541436..4abdbdff6943 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3614,6 +3614,7 @@ int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
shost->max_lun = 1;
shost->max_channel = 1;
shost->max_cmd_len = 16;
+ shost->no_write_same = 1;
/* Schedule policy is determined by ->qc_defer()
* callback and it needs to see every deferred qc.