20 files changed, 263 insertions, 97 deletions

diff --git a/drivers/scsi/be2iscsi/be_cmds.c b/drivers/scsi/be2iscsi/be_cmds.c
index 80d97f3..1028760 100644
--- a/drivers/scsi/be2iscsi/be_cmds.c
+++ b/drivers/scsi/be2iscsi/be_cmds.c
@@ -237,7 +237,7 @@ int beiscsi_mccq_compl(struct beiscsi_hba *phba,
 			beiscsi_log(phba, KERN_WARNING,
 				    BEISCSI_LOG_INIT | BEISCSI_LOG_EH |
 				    BEISCSI_LOG_CONFIG,
-				    "BC_%d : Insufficent Buffer Error "
+				    "BC_%d : Insufficient Buffer Error "
 				    "Resp_Len : %d Actual_Resp_Len : %d\n",
 				    mbx_resp_hdr->response_length,
 				    mbx_resp_hdr->actual_resp_len);
diff --git a/drivers/scsi/be2iscsi/be_main.c b/drivers/scsi/be2iscsi/be_main.c
index a7cc618..923a2b5 100644
--- a/drivers/scsi/be2iscsi/be_main.c
+++ b/drivers/scsi/be2iscsi/be_main.c
@@ -5734,9 +5734,9 @@ free_port:
 hba_free:
 	if (phba->msix_enabled)
 		pci_disable_msix(phba->pcidev);
-	iscsi_host_remove(phba->shost);
 	pci_dev_put(phba->pcidev);
 	iscsi_host_free(phba->shost);
+	pci_set_drvdata(pcidev, NULL);
 disable_pci:
 	pci_disable_device(pcidev);
 	return ret;
diff --git a/drivers/scsi/ch.c b/drivers/scsi/ch.c
index 0045742..dad959f 100644
--- a/drivers/scsi/ch.c
+++ b/drivers/scsi/ch.c
@@ -339,7 +339,7 @@ ch_readconfig(scsi_changer *ch)
 			ch->firsts[CHET_DT],
 			ch->counts[CHET_DT]);
 	} else {
-		VPRINTK(KERN_INFO, "reading element address assigment page failed!\n");
+		VPRINTK(KERN_INFO, "reading element address assignment page failed!\n");
 	}
 
 	/* vendor specific element types */
diff --git a/drivers/scsi/csiostor/csio_init.c b/drivers/scsi/csiostor/csio_init.c
index d9631e1..dbe416f 100644
--- a/drivers/scsi/csiostor/csio_init.c
+++ b/drivers/scsi/csiostor/csio_init.c
@@ -1172,7 +1172,7 @@ static struct pci_error_handlers csio_err_handler = {
  *  Macros needed to support the PCI Device ID Table ...
  */
 #define CH_PCI_DEVICE_ID_TABLE_DEFINE_BEGIN \
-	static struct pci_device_id csio_pci_tbl[] = {
+	static const struct pci_device_id csio_pci_tbl[] = {
 /* Define for FCoE uses PF6 */
 #define CH_PCI_DEVICE_ID_FUNCTION	0x6
 
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index 3128407..8827448 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -6901,7 +6901,8 @@ static struct ata_port_operations ipr_sata_ops = {
 };
 
 static struct ata_port_info sata_port_info = {
-	.flags		= ATA_FLAG_SATA | ATA_FLAG_PIO_DMA,
+	.flags		= ATA_FLAG_SATA | ATA_FLAG_PIO_DMA |
+			  ATA_FLAG_SAS_HOST,
 	.pio_mask	= ATA_PIO4_ONLY,
 	.mwdma_mask	= ATA_MWDMA2,
 	.udma_mask	= ATA_UDMA6,
diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
index 932d9cc..9c706d8 100644
--- a/drivers/scsi/libsas/sas_ata.c
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -547,7 +547,8 @@ static struct ata_port_operations sas_sata_ops = {
 };
 
 static struct ata_port_info sata_port_info = {
-	.flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ,
+	.flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ |
+		 ATA_FLAG_SAS_HOST,
 	.pio_mask = ATA_PIO4,
 	.mwdma_mask = ATA_MWDMA2,
 	.udma_mask = ATA_UDMA6,
diff --git a/drivers/scsi/libsas/sas_discover.c b/drivers/scsi/libsas/sas_discover.c
index 62b58d3..60de662 100644
--- a/drivers/scsi/libsas/sas_discover.c
+++ b/drivers/scsi/libsas/sas_discover.c
@@ -500,6 +500,7 @@ static void sas_revalidate_domain(struct work_struct *work)
 	struct sas_discovery_event *ev = to_sas_discovery_event(work);
 	struct asd_sas_port *port = ev->port;
 	struct sas_ha_struct *ha = port->ha;
+	struct domain_device *ddev = port->port_dev;
 
 	/* prevent revalidation from finding sata links in recovery */
 	mutex_lock(&ha->disco_mutex);
@@ -514,8 +515,9 @@ static void sas_revalidate_domain(struct work_struct *work)
 	SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
 		    task_pid_nr(current));
 
-	if (port->port_dev)
-		res = sas_ex_revalidate_domain(port->port_dev);
+	if (ddev && (ddev->dev_type == SAS_FANOUT_EXPANDER_DEVICE ||
+		     ddev->dev_type == SAS_EDGE_EXPANDER_DEVICE))
+		res = sas_ex_revalidate_domain(ddev);
 
 	SAS_DPRINTK("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
 		    port->id, task_pid_nr(current), res);
diff --git a/drivers/scsi/mac53c94.c b/drivers/scsi/mac53c94.c
index e5cd8d8..0adb2e0 100644
--- a/drivers/scsi/mac53c94.c
+++ b/drivers/scsi/mac53c94.c
@@ -382,16 +382,16 @@ static void set_dma_cmds(struct fsc_state *state, struct scsi_cmnd *cmd)
 		if (dma_len > 0xffff)
 			panic("mac53c94: scatterlist element >= 64k");
 		total += dma_len;
-		st_le16(&dcmds->req_count, dma_len);
-		st_le16(&dcmds->command, dma_cmd);
-		st_le32(&dcmds->phy_addr, dma_addr);
+		dcmds->req_count = cpu_to_le16(dma_len);
+		dcmds->command = cpu_to_le16(dma_cmd);
+		dcmds->phy_addr = cpu_to_le32(dma_addr);
 		dcmds->xfer_status = 0;
 		++dcmds;
 	}
 
 	dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
-	st_le16(&dcmds[-1].command, dma_cmd);
-	st_le16(&dcmds->command, DBDMA_STOP);
+	dcmds[-1].command = cpu_to_le16(dma_cmd);
+	dcmds->command = cpu_to_le16(DBDMA_STOP);
 	cmd->SCp.this_residual = total;
 }
 
diff --git a/drivers/scsi/mesh.c b/drivers/scsi/mesh.c
index 57a95e2..555367f 100644
--- a/drivers/scsi/mesh.c
+++ b/drivers/scsi/mesh.c
@@ -1287,9 +1287,9 @@ static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd)
 				}
 				if (dma_len > 0xffff)
 					panic("mesh: scatterlist element >= 64k");
-				st_le16(&dcmds->req_count, dma_len - off);
-				st_le16(&dcmds->command, dma_cmd);
-				st_le32(&dcmds->phy_addr, dma_addr + off);
+				dcmds->req_count = cpu_to_le16(dma_len - off);
+				dcmds->command = cpu_to_le16(dma_cmd);
+				dcmds->phy_addr = cpu_to_le32(dma_addr + off);
 				dcmds->xfer_status = 0;
 				++dcmds;
 				dtot += dma_len - off;
@@ -1303,15 +1303,15 @@ static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd)
 		static char mesh_extra_buf[64];
 
 		dtot = sizeof(mesh_extra_buf);
-		st_le16(&dcmds->req_count, dtot);
-		st_le32(&dcmds->phy_addr, virt_to_phys(mesh_extra_buf));
+		dcmds->req_count = cpu_to_le16(dtot);
+		dcmds->phy_addr = cpu_to_le32(virt_to_phys(mesh_extra_buf));
 		dcmds->xfer_status = 0;
 		++dcmds;
 	}
 	dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
-	st_le16(&dcmds[-1].command, dma_cmd);
+	dcmds[-1].command = cpu_to_le16(dma_cmd);
 	memset(dcmds, 0, sizeof(*dcmds));
-	st_le16(&dcmds->command, DBDMA_STOP);
+	dcmds->command = cpu_to_le16(DBDMA_STOP);
 	ms->dma_count = dtot;
 }
 
diff --git a/drivers/scsi/osd/osd_initiator.c b/drivers/scsi/osd/osd_initiator.c
index 488c392..0cccd60 100644
--- a/drivers/scsi/osd/osd_initiator.c
+++ b/drivers/scsi/osd/osd_initiator.c
@@ -186,7 +186,7 @@ static int _osd_get_print_system_info(struct osd_dev *od,
 
 		if (unlikely(len > sizeof(odi->systemid))) {
 			OSD_ERR("OSD Target error: OSD_SYSTEM_ID too long(%d). "
-				"device idetification might not work\n", len);
+				"device identification might not work\n", len);
 			len = sizeof(odi->systemid);
 		}
 		odi->systemid_len = len;
diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 22ea00eb..285cb20 100644
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -5415,7 +5415,7 @@ qla2x00_load_risc(scsi_qla_host_t *vha, uint32_t *srisc_addr)
 	blob = qla2x00_request_firmware(vha);
 	if (!blob) {
 		ql_log(ql_log_info, vha, 0x0083,
-		    "Fimware image unavailable.\n");
+		    "Firmware image unavailable.\n");
 		ql_log(ql_log_info, vha, 0x0084,
 		    "Firmware images can be retrieved from: "QLA_FW_URL ".\n");
 		return QLA_FUNCTION_FAILED;
@@ -5518,7 +5518,7 @@ qla24xx_load_risc_blob(scsi_qla_host_t *vha, uint32_t *srisc_addr)
 	blob = qla2x00_request_firmware(vha);
 	if (!blob) {
 		ql_log(ql_log_warn, vha, 0x0090,
-		    "Fimware image unavailable.\n");
+		    "Firmware image unavailable.\n");
 		ql_log(ql_log_warn, vha, 0x0091,
 		    "Firmware images can be retrieved from: "
 		    QLA_FW_URL ".\n");
diff --git a/drivers/scsi/qla2xxx/qla_mid.c b/drivers/scsi/qla2xxx/qla_mid.c
index 8f458ef..cc94192 100644
--- a/drivers/scsi/qla2xxx/qla_mid.c
+++ b/drivers/scsi/qla2xxx/qla_mid.c
@@ -794,7 +794,7 @@ qla25xx_create_rsp_que(struct qla_hw_data *ha, uint16_t options,
 		rsp->msix = &ha->msix_entries[que_id + 1];
 	else
 		ql_log(ql_log_warn, base_vha, 0x00e3,
-		    "MSIX not enalbled.\n");
+		    "MSIX not enabled.\n");
 
 	ha->rsp_q_map[que_id] = rsp;
 	rsp->rid = rid;
diff --git a/drivers/scsi/qla2xxx/qla_nx.c b/drivers/scsi/qla2xxx/qla_nx.c
index 54cb2ac..7d2b18f 100644
--- a/drivers/scsi/qla2xxx/qla_nx.c
+++ b/drivers/scsi/qla2xxx/qla_nx.c
@@ -1274,7 +1274,7 @@ qla82xx_pinit_from_rom(scsi_qla_host_t *vha)
 
 		if (off == ADDR_ERROR) {
 			ql_log(ql_log_fatal, vha, 0x0116,
-			    "Unknow addr: 0x%08lx.\n", buf[i].addr);
+			    "Unknown addr: 0x%08lx.\n", buf[i].addr);
 			continue;
 		}
 
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index e4851f8..7462dd7 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -446,11 +446,11 @@ static int qla25xx_setup_mode(struct scsi_qla_host *vha)
 		}
 		ha->flags.cpu_affinity_enabled = 1;
 		ql_dbg(ql_dbg_multiq, vha, 0xc007,
-		    "CPU affinity mode enalbed, "
+		    "CPU affinity mode enabled, "
 		    "no. of response queues:%d no. of request queues:%d.\n",
 		    ha->max_rsp_queues, ha->max_req_queues);
 		ql_dbg(ql_dbg_init, vha, 0x00e9,
-		    "CPU affinity mode enalbed, "
+		    "CPU affinity mode enabled, "
 		    "no. of response queues:%d no. of request queues:%d.\n",
 		    ha->max_rsp_queues, ha->max_req_queues);
 	}
@@ -4102,7 +4102,7 @@ qla83xx_schedule_work(scsi_qla_host_t *base_vha, int work_code)
 		break;
 	default:
 		ql_log(ql_log_warn, base_vha, 0xb05f,
-		    "Unknow work-code=0x%x.\n", work_code);
+		    "Unknown work-code=0x%x.\n", work_code);
 	}
 
 	return;
@@ -4702,7 +4702,7 @@ qla83xx_idc_state_handler(scsi_qla_host_t *base_vha)
 			break;
 		default:
 			ql_log(ql_log_warn, base_vha, 0xb071,
-			    "Unknow Device State: %x.\n", dev_state);
+			    "Unknown Device State: %x.\n", dev_state);
 			qla83xx_idc_unlock(base_vha, 0);
 			qla8xxx_dev_failed_handler(base_vha);
 			rval = QLA_FUNCTION_FAILED;
diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.c b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
index 99f43b7..ab4879e 100644
--- a/drivers/scsi/qla2xxx/tcm_qla2xxx.c
+++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
@@ -1596,7 +1596,7 @@ static int tcm_qla2xxx_check_initiator_node_acl(
 	/*
 	 * Finally register the new FC Nexus with TCM
 	 */
-	__transport_register_session(se_nacl->se_tpg, se_nacl, se_sess, sess);
+	transport_register_session(se_nacl->se_tpg, se_nacl, se_sess, sess);
 
 	return 0;
 }
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 4cdaffc..c95a4e9 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -26,6 +26,7 @@
 #include <linux/blkdev.h>
 #include <linux/delay.h>
 #include <linux/jiffies.h>
+#include <asm/unaligned.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
@@ -2586,3 +2587,33 @@ void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq)
 	}
 }
 EXPORT_SYMBOL(scsi_build_sense_buffer);
+
+/**
+ * scsi_set_sense_information - set the information field in a
+ *		formatted sense data buffer
+ * @buf:	Where to build sense data
+ * @info:	64-bit information value to be set
+ *
+ **/
+void scsi_set_sense_information(u8 *buf, u64 info)
+{
+	if ((buf[0] & 0x7f) == 0x72) {
+		u8 *ucp, len;
+
+		len = buf[7];
+		ucp = (char *)scsi_sense_desc_find(buf, len + 8, 0);
+		if (!ucp) {
+			buf[7] = len + 0xa;
+			ucp = buf + 8 + len;
+		}
+		ucp[0] = 0;
+		ucp[1] = 0xa;
+		ucp[2] = 0x80; /* Valid bit */
+		ucp[3] = 0;
+		put_unaligned_be64(info, &ucp[4]);
+	} else if ((buf[0] & 0x7f) == 0x70) {
+		buf[0] |= 0x80;
+		put_unaligned_be64(info, &buf[3]);
+	}
+}
+EXPORT_SYMBOL(scsi_set_sense_information);
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 54d7a6c..b1a2631 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1311,9 +1311,11 @@ scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
 				    "rejecting I/O to dead device\n");
 			ret = BLKPREP_KILL;
 			break;
-		case SDEV_QUIESCE:
 		case SDEV_BLOCK:
 		case SDEV_CREATED_BLOCK:
+			ret = BLKPREP_DEFER;
+			break;
+		case SDEV_QUIESCE:
 			/*
 			 * If the devices is blocked we defer normal commands.
 			 */
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 2270bd5..9d7b7db 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -33,7 +33,6 @@ static int sg_version_num = 30536;	/* 2 digits for each component */
 #include <linux/sched.h>
 #include <linux/string.h>
 #include <linux/mm.h>
-#include <linux/aio.h>
 #include <linux/errno.h>
 #include <linux/mtio.h>
 #include <linux/ioctl.h>
@@ -51,6 +50,7 @@ static int sg_version_num = 30536;	/* 2 digits for each component */
 #include <linux/mutex.h>
 #include <linux/atomic.h>
 #include <linux/ratelimit.h>
+#include <linux/uio.h>
 
 #include "scsi.h"
 #include <scsi/scsi_dbg.h>
@@ -1745,17 +1745,14 @@ sg_start_req(Sg_request *srp, unsigned char *cmd)
 	}
 
 	if (iov_count) {
-		int size = sizeof(struct iovec) * iov_count;
-		struct iovec *iov;
+		struct iovec *iov = NULL;
 		struct iov_iter i;
 
-		iov = memdup_user(hp->dxferp, size);
-		if (IS_ERR(iov))
-			return PTR_ERR(iov);
+		res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
+		if (res < 0)
+			return res;
 
-		iov_iter_init(&i, rw, iov, iov_count,
-			      min_t(size_t, hp->dxfer_len,
-				    iov_length(iov, iov_count)));
+		iov_iter_truncate(&i, hp->dxfer_len);
 
 		res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
 		kfree(iov);
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index dfd72af..648a446 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4260,22 +4260,15 @@ static struct scsi_host_template ufshcd_driver_template = {
 static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
 				   int ua)
 {
-	int ret = 0;
-	struct regulator *reg = vreg->reg;
-	const char *name = vreg->name;
+	int ret;
 
-	BUG_ON(!vreg);
+	if (!vreg)
+		return 0;
 
-	ret = regulator_set_optimum_mode(reg, ua);
-	if (ret >= 0) {
-		/*
-		 * regulator_set_optimum_mode() returns new regulator
-		 * mode upon success.
-		 */
-		ret = 0;
-	} else {
-		dev_err(dev, "%s: %s set optimum mode(ua=%d) failed, err=%d\n",
-				__func__, name, ua, ret);
+	ret = regulator_set_load(vreg->reg, ua);
+	if (ret < 0) {
+		dev_err(dev, "%s: %s set load (ua=%d) failed, err=%d\n",
+				__func__, vreg->name, ua, ret);
 	}
 
 	return ret;
@@ -4284,18 +4277,12 @@ static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
 static inline int ufshcd_config_vreg_lpm(struct ufs_hba *hba,
 					 struct ufs_vreg *vreg)
 {
-	if (!vreg)
-		return 0;
-
 	return ufshcd_config_vreg_load(hba->dev, vreg, UFS_VREG_LPM_LOAD_UA);
 }
 
 static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
 					 struct ufs_vreg *vreg)
 {
-	if (!vreg)
-		return 0;
-
 	return ufshcd_config_vreg_load(hba->dev, vreg, vreg->max_uA);
 }
 
diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c
index 34199d2..fad22ca 100644
--- a/drivers/scsi/xen-scsifront.c
+++ b/drivers/scsi/xen-scsifront.c
@@ -63,6 +63,7 @@
 
 #define VSCSIFRONT_OP_ADD_LUN	1
 #define VSCSIFRONT_OP_DEL_LUN	2
+#define VSCSIFRONT_OP_READD_LUN	3
 
 /* Tuning point. */
 #define VSCSIIF_DEFAULT_CMD_PER_LUN 10
@@ -113,8 +114,13 @@ struct vscsifrnt_info {
 	DECLARE_BITMAP(shadow_free_bitmap, VSCSIIF_MAX_REQS);
 	struct vscsifrnt_shadow *shadow[VSCSIIF_MAX_REQS];
 
+	/* Following items are protected by the host lock. */
 	wait_queue_head_t wq_sync;
+	wait_queue_head_t wq_pause;
 	unsigned int wait_ring_available:1;
+	unsigned int waiting_pause:1;
+	unsigned int pause:1;
+	unsigned callers;
 
 	char dev_state_path[64];
 	struct task_struct *curr;
@@ -274,31 +280,31 @@ static void scsifront_sync_cmd_done(struct vscsifrnt_info *info,
 	wake_up(&shadow->wq_reset);
 }
 
-static int scsifront_cmd_done(struct vscsifrnt_info *info)
+static void scsifront_do_response(struct vscsifrnt_info *info,
+				  struct vscsiif_response *ring_rsp)
+{
+	if (WARN(ring_rsp->rqid >= VSCSIIF_MAX_REQS ||
+		 test_bit(ring_rsp->rqid, info->shadow_free_bitmap),
+		 "illegal rqid %u returned by backend!\n", ring_rsp->rqid))
+		return;
+
+	if (info->shadow[ring_rsp->rqid]->act == VSCSIIF_ACT_SCSI_CDB)
+		scsifront_cdb_cmd_done(info, ring_rsp);
+	else
+		scsifront_sync_cmd_done(info, ring_rsp);
+}
+
+static int scsifront_ring_drain(struct vscsifrnt_info *info)
 {
 	struct vscsiif_response *ring_rsp;
 	RING_IDX i, rp;
 	int more_to_do = 0;
-	unsigned long flags;
-
-	spin_lock_irqsave(info->host->host_lock, flags);
 
 	rp = info->ring.sring->rsp_prod;
 	rmb();	/* ordering required respective to dom0 */
 	for (i = info->ring.rsp_cons; i != rp; i++) {
-
 		ring_rsp = RING_GET_RESPONSE(&info->ring, i);
-
-		if (WARN(ring_rsp->rqid >= VSCSIIF_MAX_REQS ||
-			 test_bit(ring_rsp->rqid, info->shadow_free_bitmap),
-			 "illegal rqid %u returned by backend!\n",
-			 ring_rsp->rqid))
-			continue;
-
-		if (info->shadow[ring_rsp->rqid]->act == VSCSIIF_ACT_SCSI_CDB)
-			scsifront_cdb_cmd_done(info, ring_rsp);
-		else
-			scsifront_sync_cmd_done(info, ring_rsp);
+		scsifront_do_response(info, ring_rsp);
 	}
 
 	info->ring.rsp_cons = i;
@@ -308,6 +314,18 @@ static int scsifront_cmd_done(struct vscsifrnt_info *info)
 	else
 		info->ring.sring->rsp_event = i + 1;
 
+	return more_to_do;
+}
+
+static int scsifront_cmd_done(struct vscsifrnt_info *info)
+{
+	int more_to_do;
+	unsigned long flags;
+
+	spin_lock_irqsave(info->host->host_lock, flags);
+
+	more_to_do = scsifront_ring_drain(info);
+
 	info->wait_ring_available = 0;
 
 	spin_unlock_irqrestore(info->host->host_lock, flags);
@@ -328,6 +346,24 @@ static irqreturn_t scsifront_irq_fn(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static void scsifront_finish_all(struct vscsifrnt_info *info)
+{
+	unsigned i;
+	struct vscsiif_response resp;
+
+	scsifront_ring_drain(info);
+
+	for (i = 0; i < VSCSIIF_MAX_REQS; i++) {
+		if (test_bit(i, info->shadow_free_bitmap))
+			continue;
+		resp.rqid = i;
+		resp.sense_len = 0;
+		resp.rslt = DID_RESET << 16;
+		resp.residual_len = 0;
+		scsifront_do_response(info, &resp);
+	}
+}
+
 static int map_data_for_request(struct vscsifrnt_info *info,
 				struct scsi_cmnd *sc,
 				struct vscsiif_request *ring_req,
@@ -475,6 +511,27 @@ static struct vscsiif_request *scsifront_command2ring(
 	return ring_req;
 }
 
+static int scsifront_enter(struct vscsifrnt_info *info)
+{
+	if (info->pause)
+		return 1;
+	info->callers++;
+	return 0;
+}
+
+static void scsifront_return(struct vscsifrnt_info *info)
+{
+	info->callers--;
+	if (info->callers)
+		return;
+
+	if (!info->waiting_pause)
+		return;
+
+	info->waiting_pause = 0;
+	wake_up(&info->wq_pause);
+}
+
 static int scsifront_queuecommand(struct Scsi_Host *shost,
 				  struct scsi_cmnd *sc)
 {
@@ -486,6 +543,10 @@ static int scsifront_queuecommand(struct Scsi_Host *shost,
 	uint16_t rqid;
 
 	spin_lock_irqsave(shost->host_lock, flags);
+	if (scsifront_enter(info)) {
+		spin_unlock_irqrestore(shost->host_lock, flags);
+		return SCSI_MLQUEUE_HOST_BUSY;
+	}
 	if (RING_FULL(&info->ring))
 		goto busy;
 
@@ -505,6 +566,7 @@ static int scsifront_queuecommand(struct Scsi_Host *shost,
 	if (err < 0) {
 		pr_debug("%s: err %d\n", __func__, err);
 		scsifront_put_rqid(info, rqid);
+		scsifront_return(info);
 		spin_unlock_irqrestore(shost->host_lock, flags);
 		if (err == -ENOMEM)
 			return SCSI_MLQUEUE_HOST_BUSY;
@@ -514,11 +576,13 @@ static int scsifront_queuecommand(struct Scsi_Host *shost,
 	}
 
 	scsifront_do_request(info);
+	scsifront_return(info);
 	spin_unlock_irqrestore(shost->host_lock, flags);
 
 	return 0;
 
 busy:
+	scsifront_return(info);
 	spin_unlock_irqrestore(shost->host_lock, flags);
 	pr_debug("%s: busy\n", __func__);
 	return SCSI_MLQUEUE_HOST_BUSY;
@@ -549,7 +613,7 @@ static int scsifront_action_handler(struct scsi_cmnd *sc, uint8_t act)
 			if (ring_req)
 				break;
 		}
-		if (err) {
+		if (err || info->pause) {
 			spin_unlock_irq(host->host_lock);
 			kfree(shadow);
 			return FAILED;
@@ -561,6 +625,11 @@ static int scsifront_action_handler(struct scsi_cmnd *sc, uint8_t act)
 		spin_lock_irq(host->host_lock);
 	}
 
+	if (scsifront_enter(info)) {
+		spin_unlock_irq(host->host_lock);
+		return FAILED;
+	}
+
 	ring_req->act = act;
 	ring_req->ref_rqid = s->rqid;
 
@@ -587,6 +656,7 @@ static int scsifront_action_handler(struct scsi_cmnd *sc, uint8_t act)
 		err = FAILED;
 	}
 
+	scsifront_return(info);
 	spin_unlock_irq(host->host_lock);
 	return err;
 }
@@ -644,6 +714,7 @@ static int scsifront_alloc_ring(struct vscsifrnt_info *info)
 {
 	struct xenbus_device *dev = info->dev;
 	struct vscsiif_sring *sring;
+	grant_ref_t gref;
 	int err = -ENOMEM;
 
 	/***** Frontend to Backend ring start *****/
@@ -656,14 +727,14 @@ static int scsifront_alloc_ring(struct vscsifrnt_info *info)
 	SHARED_RING_INIT(sring);
 	FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE);
 
-	err = xenbus_grant_ring(dev, virt_to_mfn(sring));
+	err = xenbus_grant_ring(dev, sring, 1, &gref);
 	if (err < 0) {
 		free_page((unsigned long)sring);
 		xenbus_dev_fatal(dev, err,
 			"fail to grant shared ring (Front to Back)");
 		return err;
 	}
-	info->ring_ref = err;
+	info->ring_ref = gref;
 
 	err = xenbus_alloc_evtchn(dev, &info->evtchn);
 	if (err) {
@@ -698,6 +769,13 @@ free_gnttab:
 	return err;
 }
 
+static void scsifront_free_ring(struct vscsifrnt_info *info)
+{
+	unbind_from_irqhandler(info->irq, info);
+	gnttab_end_foreign_access(info->ring_ref, 0,
+				  (unsigned long)info->ring.sring);
+}
+
 static int scsifront_init_ring(struct vscsifrnt_info *info)
 {
 	struct xenbus_device *dev = info->dev;
@@ -744,9 +822,7 @@ again:
 fail:
 	xenbus_transaction_end(xbt, 1);
 free_sring:
-	unbind_from_irqhandler(info->irq, info);
-	gnttab_end_foreign_access(info->ring_ref, 0,
-				  (unsigned long)info->ring.sring);
+	scsifront_free_ring(info);
 
 	return err;
 }
@@ -779,6 +855,7 @@ static int scsifront_probe(struct xenbus_device *dev,
 	}
 
 	init_waitqueue_head(&info->wq_sync);
+	init_waitqueue_head(&info->wq_pause);
 	spin_lock_init(&info->shadow_lock);
 
 	snprintf(name, TASK_COMM_LEN, "vscsiif.%d", host->host_no);
@@ -802,13 +879,60 @@ static int scsifront_probe(struct xenbus_device *dev,
 	return 0;
 
 free_sring:
-	unbind_from_irqhandler(info->irq, info);
-	gnttab_end_foreign_access(info->ring_ref, 0,
-				  (unsigned long)info->ring.sring);
+	scsifront_free_ring(info);
 	scsi_host_put(host);
 	return err;
 }
 
+static int scsifront_resume(struct xenbus_device *dev)
+{
+	struct vscsifrnt_info *info = dev_get_drvdata(&dev->dev);
+	struct Scsi_Host *host = info->host;
+	int err;
+
+	spin_lock_irq(host->host_lock);
+
+	/* Finish all still pending commands. */
+	scsifront_finish_all(info);
+
+	spin_unlock_irq(host->host_lock);
+
+	/* Reconnect to dom0. */
+	scsifront_free_ring(info);
+	err = scsifront_init_ring(info);
+	if (err) {
+		dev_err(&dev->dev, "fail to resume %d\n", err);
+		scsi_host_put(host);
+		return err;
+	}
+
+	xenbus_switch_state(dev, XenbusStateInitialised);
+
+	return 0;
+}
+
+static int scsifront_suspend(struct xenbus_device *dev)
+{
+	struct vscsifrnt_info *info = dev_get_drvdata(&dev->dev);
+	struct Scsi_Host *host = info->host;
+	int err = 0;
+
+	/* No new commands for the backend. */
+	spin_lock_irq(host->host_lock);
+	info->pause = 1;
+	while (info->callers && !err) {
+		info->waiting_pause = 1;
+		info->wait_ring_available = 0;
+		spin_unlock_irq(host->host_lock);
+		wake_up(&info->wq_sync);
+		err = wait_event_interruptible(info->wq_pause,
+					       !info->waiting_pause);
+		spin_lock_irq(host->host_lock);
+	}
+	spin_unlock_irq(host->host_lock);
+	return err;
+}
+
 static int scsifront_remove(struct xenbus_device *dev)
 {
 	struct vscsifrnt_info *info = dev_get_drvdata(&dev->dev);
@@ -823,10 +947,7 @@ static int scsifront_remove(struct xenbus_device *dev)
 	}
 	mutex_unlock(&scsifront_mutex);
 
-	gnttab_end_foreign_access(info->ring_ref, 0,
-				  (unsigned long)info->ring.sring);
-	unbind_from_irqhandler(info->irq, info);
-
+	scsifront_free_ring(info);
 	scsi_host_put(info->host);
 
 	return 0;
@@ -919,6 +1040,12 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op)
 				scsi_device_put(sdev);
 			}
 			break;
+		case VSCSIFRONT_OP_READD_LUN:
+			if (device_state == XenbusStateConnected)
+				xenbus_printf(XBT_NIL, dev->nodename,
+					      info->dev_state_path,
+					      "%d", XenbusStateConnected);
+			break;
 		default:
 			break;
 		}
@@ -932,21 +1059,29 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op)
 static void scsifront_read_backend_params(struct xenbus_device *dev,
 					  struct vscsifrnt_info *info)
 {
-	unsigned int sg_grant;
+	unsigned int sg_grant, nr_segs;
 	int ret;
 	struct Scsi_Host *host = info->host;
 
 	ret = xenbus_scanf(XBT_NIL, dev->otherend, "feature-sg-grant", "%u",
 			   &sg_grant);
-	if (ret == 1 && sg_grant) {
-		sg_grant = min_t(unsigned int, sg_grant, SG_ALL);
-		sg_grant = max_t(unsigned int, sg_grant, VSCSIIF_SG_TABLESIZE);
-		host->sg_tablesize = min_t(unsigned int, sg_grant,
+	if (ret != 1)
+		sg_grant = 0;
+	nr_segs = min_t(unsigned int, sg_grant, SG_ALL);
+	nr_segs = max_t(unsigned int, nr_segs, VSCSIIF_SG_TABLESIZE);
+	nr_segs = min_t(unsigned int, nr_segs,
 			VSCSIIF_SG_TABLESIZE * PAGE_SIZE /
 			sizeof(struct scsiif_request_segment));
-		host->max_sectors = (host->sg_tablesize - 1) * PAGE_SIZE / 512;
-	}
-	dev_info(&dev->dev, "using up to %d SG entries\n", host->sg_tablesize);
+
+	if (!info->pause && sg_grant)
+		dev_info(&dev->dev, "using up to %d SG entries\n", nr_segs);
+	else if (info->pause && nr_segs < host->sg_tablesize)
+		dev_warn(&dev->dev,
+			 "SG entries decreased from %d to %u - device may not work properly anymore\n",
+			 host->sg_tablesize, nr_segs);
+
+	host->sg_tablesize = nr_segs;
+	host->max_sectors = (nr_segs - 1) * PAGE_SIZE / 512;
 }
 
 static void scsifront_backend_changed(struct xenbus_device *dev,
@@ -965,6 +1100,14 @@ static void scsifront_backend_changed(struct xenbus_device *dev,
 
 	case XenbusStateConnected:
 		scsifront_read_backend_params(dev, info);
+
+		if (info->pause) {
+			scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_READD_LUN);
+			xenbus_switch_state(dev, XenbusStateConnected);
+			info->pause = 0;
+			return;
+		}
+
 		if (xenbus_read_driver_state(dev->nodename) ==
 		    XenbusStateInitialised)
 			scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_ADD_LUN);
@@ -1002,6 +1145,8 @@ static struct xenbus_driver scsifront_driver = {
 	.ids			= scsifront_ids,
 	.probe			= scsifront_probe,
 	.remove			= scsifront_remove,
+	.resume			= scsifront_resume,
+	.suspend		= scsifront_suspend,
 	.otherend_changed	= scsifront_backend_changed,
 };