releases/3.12.5/scsi-disable-write-same-for-raid-and-virtual-host-adapter-drivers.patch

From 54b2b50c20a61b51199bedb6e5d2f8ec2568fb43 Mon Sep 17 00:00:00 2001
From: "Martin K. Petersen" <martin.petersen@oracle.com>
Date: Wed, 23 Oct 2013 06:25:40 -0400
Subject: SCSI: Disable WRITE SAME for RAID and virtual host adapter drivers

From: "Martin K. Petersen" <martin.petersen@oracle.com>

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>

---
 drivers/ata/libata-scsi.c                 |    1 +
 drivers/firewire/sbp2.c                   |    1 +
 drivers/scsi/3w-9xxx.c                    |    3 ++-
 drivers/scsi/3w-sas.c                     |    3 ++-
 drivers/scsi/3w-xxxx.c                    |    3 ++-
 drivers/scsi/aacraid/linit.c              |    1 +
 drivers/scsi/arcmsr/arcmsr_hba.c          |    1 +
 drivers/scsi/gdth.c                       |    1 +
 drivers/scsi/hosts.c                      |    1 +
 drivers/scsi/hpsa.c                       |    1 +
 drivers/scsi/ipr.c                        |    3 ++-
 drivers/scsi/ips.c                        |    1 +
 drivers/scsi/megaraid.c                   |    1 +
 drivers/scsi/megaraid/megaraid_mbox.c     |    1 +
 drivers/scsi/megaraid/megaraid_sas_base.c |    1 +
 drivers/scsi/pmcraid.c                    |    1 +
 drivers/scsi/sd.c                         |    6 ++++++
 drivers/scsi/storvsc_drv.c                |    1 +
 include/scsi/scsi_host.h                  |    6 ++++++
 19 files changed, 33 insertions(+), 4 deletions(-)

--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3625,6 +3625,7 @@ int ata_scsi_add_hosts(struct ata_host *
 		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.
--- a/drivers/firewire/sbp2.c
+++ b/drivers/firewire/sbp2.c
@@ -1623,6 +1623,7 @@ static struct scsi_host_template scsi_dr
 	.cmd_per_lun		= 1,
 	.can_queue		= 1,
 	.sdev_attrs		= sbp2_scsi_sysfs_attrs,
+	.no_write_same		= 1,
 };
 
 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
--- a/drivers/scsi/3w-9xxx.c
+++ b/drivers/scsi/3w-9xxx.c
@@ -2025,7 +2025,8 @@ static struct scsi_host_template driver_
 	.cmd_per_lun		= TW_MAX_CMDS_PER_LUN,
 	.use_clustering		= ENABLE_CLUSTERING,
 	.shost_attrs		= twa_host_attrs,
-	.emulated		= 1
+	.emulated		= 1,
+	.no_write_same		= 1,
 };
 
 /* This function will probe and initialize a card */
--- a/drivers/scsi/3w-sas.c
+++ b/drivers/scsi/3w-sas.c
@@ -1600,7 +1600,8 @@ static struct scsi_host_template driver_
 	.cmd_per_lun		= TW_MAX_CMDS_PER_LUN,
 	.use_clustering		= ENABLE_CLUSTERING,
 	.shost_attrs		= twl_host_attrs,
-	.emulated		= 1
+	.emulated		= 1,
+	.no_write_same		= 1,
 };
 
 /* This function will probe and initialize a card */
--- a/drivers/scsi/3w-xxxx.c
+++ b/drivers/scsi/3w-xxxx.c
@@ -2279,7 +2279,8 @@ static struct scsi_host_template driver_
 	.cmd_per_lun		= TW_MAX_CMDS_PER_LUN,	
 	.use_clustering		= ENABLE_CLUSTERING,
 	.shost_attrs		= tw_host_attrs,
-	.emulated		= 1
+	.emulated		= 1,
+	.no_write_same		= 1,
 };
 
 /* This function will probe and initialize a card */
--- a/drivers/scsi/aacraid/linit.c
+++ b/drivers/scsi/aacraid/linit.c
@@ -1081,6 +1081,7 @@ static struct scsi_host_template aac_dri
 #endif
 	.use_clustering			= ENABLE_CLUSTERING,
 	.emulated			= 1,
+	.no_write_same			= 1,
 };
 
 static void __aac_shutdown(struct aac_dev * aac)
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -137,6 +137,7 @@ static struct scsi_host_template arcmsr_
 	.cmd_per_lun		= ARCMSR_MAX_CMD_PERLUN,
 	.use_clustering		= ENABLE_CLUSTERING,
 	.shost_attrs		= arcmsr_host_attrs,
+	.no_write_same		= 1,
 };
 static struct pci_device_id arcmsr_device_id_table[] = {
 	{PCI_DEVICE(PCI_VENDOR_ID_ARECA, PCI_DEVICE_ID_ARECA_1110)},
--- a/drivers/scsi/gdth.c
+++ b/drivers/scsi/gdth.c
@@ -4686,6 +4686,7 @@ static struct scsi_host_template gdth_te
         .cmd_per_lun            = GDTH_MAXC_P_L,
         .unchecked_isa_dma      = 1,
         .use_clustering         = ENABLE_CLUSTERING,
+	.no_write_same		= 1,
 };
 
 #ifdef CONFIG_ISA
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -388,6 +388,7 @@ struct Scsi_Host *scsi_host_alloc(struct
 	shost->unchecked_isa_dma = sht->unchecked_isa_dma;
 	shost->use_clustering = sht->use_clustering;
 	shost->ordered_tag = sht->ordered_tag;
+	shost->no_write_same = sht->no_write_same;
 
 	if (sht->supported_mode == MODE_UNKNOWN)
 		/* means we didn't set it ... default to INITIATOR */
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -562,6 +562,7 @@ static struct scsi_host_template hpsa_dr
 	.sdev_attrs = hpsa_sdev_attrs,
 	.shost_attrs = hpsa_shost_attrs,
 	.max_sectors = 8192,
+	.no_write_same = 1,
 };
 
 
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -6305,7 +6305,8 @@ static struct scsi_host_template driver_
 	.use_clustering = ENABLE_CLUSTERING,
 	.shost_attrs = ipr_ioa_attrs,
 	.sdev_attrs = ipr_dev_attrs,
-	.proc_name = IPR_NAME
+	.proc_name = IPR_NAME,
+	.no_write_same = 1,
 };
 
 /**
--- a/drivers/scsi/ips.c
+++ b/drivers/scsi/ips.c
@@ -374,6 +374,7 @@ static struct scsi_host_template ips_dri
 	.sg_tablesize		= IPS_MAX_SG,
 	.cmd_per_lun		= 3,
 	.use_clustering		= ENABLE_CLUSTERING,
+	.no_write_same		= 1,
 };
 
 
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -4244,6 +4244,7 @@ static struct scsi_host_template megarai
 	.eh_device_reset_handler	= megaraid_reset,
 	.eh_bus_reset_handler		= megaraid_reset,
 	.eh_host_reset_handler		= megaraid_reset,
+	.no_write_same			= 1,
 };
 
 static int
--- a/drivers/scsi/megaraid/megaraid_mbox.c
+++ b/drivers/scsi/megaraid/megaraid_mbox.c
@@ -367,6 +367,7 @@ static struct scsi_host_template megarai
 	.eh_host_reset_handler		= megaraid_reset_handler,
 	.change_queue_depth		= megaraid_change_queue_depth,
 	.use_clustering			= ENABLE_CLUSTERING,
+	.no_write_same			= 1,
 	.sdev_attrs			= megaraid_sdev_attrs,
 	.shost_attrs			= megaraid_shost_attrs,
 };
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -2148,6 +2148,7 @@ static struct scsi_host_template megasas
 	.bios_param = megasas_bios_param,
 	.use_clustering = ENABLE_CLUSTERING,
 	.change_queue_depth = megasas_change_queue_depth,
+	.no_write_same = 1,
 };
 
 /**
--- a/drivers/scsi/pmcraid.c
+++ b/drivers/scsi/pmcraid.c
@@ -4314,6 +4314,7 @@ static struct scsi_host_template pmcraid
 	.this_id = -1,
 	.sg_tablesize = PMCRAID_MAX_IOADLS,
 	.max_sectors = PMCRAID_IOA_MAX_SECTORS,
+	.no_write_same = 1,
 	.cmd_per_lun = PMCRAID_MAX_CMD_PER_LUN,
 	.use_clustering = ENABLE_CLUSTERING,
 	.shost_attrs = pmcraid_host_attrs,
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2638,6 +2638,12 @@ static void sd_read_write_same(struct sc
 {
 	struct scsi_device *sdev = sdkp->device;
 
+	if (sdev->host->no_write_same) {
+		sdev->no_write_same = 1;
+
+		return;
+	}
+
 	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, INQUIRY) < 0) {
 		sdev->no_report_opcodes = 1;
 
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1697,6 +1697,7 @@ static struct scsi_host_template scsi_dr
 	.use_clustering =	DISABLE_CLUSTERING,
 	/* Make sure we dont get a sg segment crosses a page boundary */
 	.dma_boundary =		PAGE_SIZE-1,
+	.no_write_same =	1,
 };
 
 enum {
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -475,6 +475,9 @@ struct scsi_host_template {
 	 */
 	unsigned ordered_tag:1;
 
+	/* True if the controller does not support WRITE SAME */
+	unsigned no_write_same:1;
+
 	/*
 	 * Countdown for host blocking with no commands outstanding.
 	 */
@@ -674,6 +677,9 @@ struct Scsi_Host {
 	/* Don't resume host in EH */
 	unsigned eh_noresume:1;
 
+	/* The controller does not support WRITE SAME */
+	unsigned no_write_same:1;
+
 	/*
 	 * Optional work queue to be utilized by the transport
 	 */