3 files changed, 75 insertions, 44 deletions

diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index fbc1d5c3b0a7..b10eefe735c5 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -85,7 +85,7 @@
 static int max_id = 64;
 static int max_channel = 3;
 static int init_timeout = 5;
-static int max_requests = 50;
+static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
 
 #define IBMVSCSI_VERSION "1.5.8"
 
@@ -538,7 +538,8 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 	int request_status;
 	int rc;
 
-	/* If we have exhausted our request limit, just fail this request.
+	/* If we have exhausted our request limit, just fail this request,
+	 * unless it is for a reset or abort.
 	 * Note that there are rare cases involving driver generated requests 
 	 * (such as task management requests) that the mid layer may think we
 	 * can handle more requests (can_queue) when we actually can't
@@ -551,9 +552,30 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 		 */
 		if (request_status < -1)
 			goto send_error;
-		/* Otherwise, if we have run out of requests */
-		else if (request_status < 0)
-			goto send_busy;
+		/* Otherwise, we may have run out of requests. */
+		/* Abort and reset calls should make it through.
+		 * Nothing except abort and reset should use the last two
+		 * slots unless we had two or less to begin with.
+		 */
+		else if (request_status < 2 &&
+		         evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
+			/* In the case that we have less than two requests
+			 * available, check the server limit as a combination
+			 * of the request limit and the number of requests
+			 * in-flight (the size of the send list).  If the
+			 * server limit is greater than 2, return busy so
+			 * that the last two are reserved for reset and abort.
+			 */
+			int server_limit = request_status;
+			struct srp_event_struct *tmp_evt;
+
+			list_for_each_entry(tmp_evt, &hostdata->sent, list) {
+				server_limit++;
+			}
+
+			if (server_limit > 2)
+				goto send_busy;
+		}
 	}
 
 	/* Copy the IU into the transfer area */
@@ -572,6 +594,7 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 
 		printk(KERN_ERR "ibmvscsi: send error %d\n",
 		       rc);
+		atomic_inc(&hostdata->request_limit);
 		goto send_error;
 	}
 
@@ -581,7 +604,8 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 	unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 
 	free_event_struct(&hostdata->pool, evt_struct);
- 	return SCSI_MLQUEUE_HOST_BUSY;
+	atomic_inc(&hostdata->request_limit);
+	return SCSI_MLQUEUE_HOST_BUSY;
 
  send_error:
 	unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
@@ -831,23 +855,16 @@ static void login_rsp(struct srp_event_struct *evt_struct)
 
 	printk(KERN_INFO "ibmvscsi: SRP_LOGIN succeeded\n");
 
-	if (evt_struct->xfer_iu->srp.login_rsp.req_lim_delta >
-	    (max_requests - 2))
-		evt_struct->xfer_iu->srp.login_rsp.req_lim_delta =
-		    max_requests - 2;
+	if (evt_struct->xfer_iu->srp.login_rsp.req_lim_delta < 0)
+		printk(KERN_ERR "ibmvscsi: Invalid request_limit.\n");
 
-	/* Now we know what the real request-limit is */
+	/* Now we know what the real request-limit is.
+	 * This value is set rather than added to request_limit because
+	 * request_limit could have been set to -1 by this client.
+	 */
 	atomic_set(&hostdata->request_limit,
 		   evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
 
-	hostdata->host->can_queue =
-	    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta - 2;
-
-	if (hostdata->host->can_queue < 1) {
-		printk(KERN_ERR "ibmvscsi: Invalid request_limit_delta\n");
-		return;
-	}
-
 	/* If we had any pending I/Os, kick them */
 	scsi_unblock_requests(hostdata->host);
 
@@ -1337,6 +1354,27 @@ static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
 	return rc;
 }
 
+/**
+ * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
+ * @sdev:	struct scsi_device device to configure
+ *
+ * Enable allow_restart for a device if it is a disk.  Adjust the
+ * queue_depth here also as is required by the documentation for
+ * struct scsi_host_template.
+ */
+static int ibmvscsi_slave_configure(struct scsi_device *sdev)
+{
+	struct Scsi_Host *shost = sdev->host;
+	unsigned long lock_flags = 0;
+
+	spin_lock_irqsave(shost->host_lock, lock_flags);
+	if (sdev->type == TYPE_DISK)
+		sdev->allow_restart = 1;
+	scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
+	spin_unlock_irqrestore(shost->host_lock, lock_flags);
+	return 0;
+}
+
 /* ------------------------------------------------------------
  * sysfs attributes
  */
@@ -1482,8 +1520,9 @@ static struct scsi_host_template driver_template = {
 	.queuecommand = ibmvscsi_queuecommand,
 	.eh_abort_handler = ibmvscsi_eh_abort_handler,
 	.eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
+	.slave_configure = ibmvscsi_slave_configure,
 	.cmd_per_lun = 16,
-	.can_queue = 1,		/* Updated after SRP_LOGIN */
+	.can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
 	.this_id = -1,
 	.sg_tablesize = SG_ALL,
 	.use_clustering = ENABLE_CLUSTERING,
@@ -1503,6 +1542,7 @@ static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 
 	vdev->dev.driver_data = NULL;
 
+	driver_template.can_queue = max_requests;
 	host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
 	if (!host) {
 		printk(KERN_ERR "ibmvscsi: couldn't allocate host data\n");
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.h b/drivers/scsi/ibmvscsi/ibmvscsi.h
index 5c6d93582929..77cc1d40f5bb 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.h
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.h
@@ -44,6 +44,8 @@ struct Scsi_Host;
  */
 #define MAX_INDIRECT_BUFS 10
 
+#define IBMVSCSI_MAX_REQUESTS_DEFAULT 100
+
 /* ------------------------------------------------------------
  * Data Structures
  */
diff --git a/drivers/scsi/ibmvscsi/ibmvstgt.c b/drivers/scsi/ibmvscsi/ibmvstgt.c
index a39a478bb39a..6d223dd76440 100644
--- a/drivers/scsi/ibmvscsi/ibmvstgt.c
+++ b/drivers/scsi/ibmvscsi/ibmvstgt.c
@@ -35,7 +35,7 @@
 #include "ibmvscsi.h"
 
 #define	INITIAL_SRP_LIMIT	16
-#define	DEFAULT_MAX_SECTORS	512
+#define	DEFAULT_MAX_SECTORS	256
 
 #define	TGT_NAME	"ibmvstgt"
 
@@ -248,8 +248,8 @@ static int ibmvstgt_rdma(struct scsi_cmnd *sc, struct scatterlist *sg, int nsg,
 						  md[i].va + mdone);
 
 			if (err != H_SUCCESS) {
-				eprintk("rdma error %d %d\n", dir, slen);
-				goto out;
+				eprintk("rdma error %d %d %ld\n", dir, slen, err);
+				return -EIO;
 			}
 
 			mlen -= slen;
@@ -265,45 +265,35 @@ static int ibmvstgt_rdma(struct scsi_cmnd *sc, struct scatterlist *sg, int nsg,
 				if (sidx > nsg) {
 					eprintk("out of sg %p %d %d\n",
 						iue, sidx, nsg);
-					goto out;
+					return -EIO;
 				}
 			}
 		};
 
 		rest -= mlen;
 	}
-out:
-
 	return 0;
 }
 
-static int ibmvstgt_transfer_data(struct scsi_cmnd *sc,
-				  void (*done)(struct scsi_cmnd *))
-{
-	struct iu_entry	*iue = (struct iu_entry *) sc->SCp.ptr;
-	int err;
-
-	err = srp_transfer_data(sc, &vio_iu(iue)->srp.cmd, ibmvstgt_rdma, 1, 1);
-
-	done(sc);
-
-	return err;
-}
-
 static int ibmvstgt_cmd_done(struct scsi_cmnd *sc,
 			     void (*done)(struct scsi_cmnd *))
 {
 	unsigned long flags;
 	struct iu_entry *iue = (struct iu_entry *) sc->SCp.ptr;
 	struct srp_target *target = iue->target;
+	int err = 0;
 
-	dprintk("%p %p %x\n", iue, target, vio_iu(iue)->srp.cmd.cdb[0]);
+	dprintk("%p %p %x %u\n", iue, target, vio_iu(iue)->srp.cmd.cdb[0],
+		cmd->usg_sg);
+
+	if (sc->use_sg)
+		err = srp_transfer_data(sc, &vio_iu(iue)->srp.cmd, ibmvstgt_rdma, 1, 1);
 
 	spin_lock_irqsave(&target->lock, flags);
 	list_del(&iue->ilist);
 	spin_unlock_irqrestore(&target->lock, flags);
 
-	if (sc->result != SAM_STAT_GOOD) {
+	if (err|| sc->result != SAM_STAT_GOOD) {
 		eprintk("operation failed %p %d %x\n",
 			iue, sc->result, vio_iu(iue)->srp.cmd.cdb[0]);
 		send_rsp(iue, sc, HARDWARE_ERROR, 0x00);
@@ -503,7 +493,8 @@ static void process_iu(struct viosrp_crq *crq, struct srp_target *target)
 {
 	struct vio_port *vport = target_to_port(target);
 	struct iu_entry *iue;
-	long err, done;
+	long err;
+	int done = 1;
 
 	iue = srp_iu_get(target);
 	if (!iue) {
@@ -518,7 +509,6 @@ static void process_iu(struct viosrp_crq *crq, struct srp_target *target)
 
 	if (err != H_SUCCESS) {
 		eprintk("%ld transferring data error %p\n", err, iue);
-		done = 1;
 		goto out;
 	}
 
@@ -794,7 +784,6 @@ static struct scsi_host_template ibmvstgt_sht = {
 	.use_clustering		= DISABLE_CLUSTERING,
 	.max_sectors		= DEFAULT_MAX_SECTORS,
 	.transfer_response	= ibmvstgt_cmd_done,
-	.transfer_data		= ibmvstgt_transfer_data,
 	.eh_abort_handler	= ibmvstgt_eh_abort_handler,
 	.tsk_mgmt_response	= ibmvstgt_tsk_mgmt_response,
 	.shost_attrs		= ibmvstgt_attrs,