5 files changed, 35 insertions, 17 deletions

diff --git a/drivers/scsi/am53c974.c b/drivers/scsi/am53c974.c
index aa3e2c7..a6f5ee8 100644
--- a/drivers/scsi/am53c974.c
+++ b/drivers/scsi/am53c974.c
@@ -178,12 +178,6 @@ static void pci_esp_dma_drain(struct esp *esp)
 			break;
 		cpu_relax();
 	}
-	if (resid > 1) {
-		/* FIFO not cleared */
-		shost_printk(KERN_INFO, esp->host,
-			     "FIFO not cleared, %d bytes left\n",
-			     resid);
-	}
 
 	/*
 	 * When there is a residual BCMPLT will never be set
diff --git a/drivers/scsi/be2iscsi/be_main.c b/drivers/scsi/be2iscsi/be_main.c
index 96241b2..a7cc618 100644
--- a/drivers/scsi/be2iscsi/be_main.c
+++ b/drivers/scsi/be2iscsi/be_main.c
@@ -585,7 +585,6 @@ static struct beiscsi_hba *beiscsi_hba_alloc(struct pci_dev *pcidev)
 			"beiscsi_hba_alloc - iscsi_host_alloc failed\n");
 		return NULL;
 	}
-	shost->dma_boundary = pcidev->dma_mask;
 	shost->max_id = BE2_MAX_SESSIONS;
 	shost->max_channel = 0;
 	shost->max_cmd_len = BEISCSI_MAX_CMD_LEN;
diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 95d581c..a1cfbd3 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -6831,10 +6831,8 @@ static struct workqueue_struct *hpsa_create_controller_wq(struct ctlr_info *h,
 						char *name)
 {
 	struct workqueue_struct *wq = NULL;
-	char wq_name[20];
 
-	snprintf(wq_name, sizeof(wq_name), "%s_%d_hpsa", name, h->ctlr);
-	wq = alloc_ordered_workqueue(wq_name, 0);
+	wq = alloc_ordered_workqueue("%s_%d_hpsa", 0, name, h->ctlr);
 	if (!wq)
 		dev_err(&h->pdev->dev, "failed to create %s workqueue\n", name);
 
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 0cbc1fb..2270bd5 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -546,7 +546,7 @@ static ssize_t
 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 {
 	sg_io_hdr_t *hp = &srp->header;
-	int err = 0;
+	int err = 0, err2;
 	int len;
 
 	if (count < SZ_SG_IO_HDR) {
@@ -575,8 +575,8 @@ sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 		goto err_out;
 	}
 err_out:
-	err = sg_finish_rem_req(srp);
-	return (0 == err) ? count : err;
+	err2 = sg_finish_rem_req(srp);
+	return err ? : err2 ? : count;
 }
 
 static ssize_t
@@ -1335,6 +1335,17 @@ sg_rq_end_io(struct request *rq, int uptodate)
 	}
 	/* Rely on write phase to clean out srp status values, so no "else" */
 
+	/*
+	 * Free the request as soon as it is complete so that its resources
+	 * can be reused without waiting for userspace to read() the
+	 * result.  But keep the associated bio (if any) around until
+	 * blk_rq_unmap_user() can be called from user context.
+	 */
+	srp->rq = NULL;
+	if (rq->cmd != rq->__cmd)
+		kfree(rq->cmd);
+	__blk_put_request(rq->q, rq);
+
 	write_lock_irqsave(&sfp->rq_list_lock, iflags);
 	if (unlikely(srp->orphan)) {
 		if (sfp->keep_orphan)
@@ -1669,7 +1680,22 @@ sg_start_req(Sg_request *srp, unsigned char *cmd)
 			return -ENOMEM;
 	}
 
-	rq = blk_get_request(q, rw, GFP_ATOMIC);
+	/*
+	 * NOTE
+	 *
+	 * With scsi-mq enabled, there are a fixed number of preallocated
+	 * requests equal in number to shost->can_queue.  If all of the
+	 * preallocated requests are already in use, then using GFP_ATOMIC with
+	 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
+	 * will cause blk_get_request() to sleep until an active command
+	 * completes, freeing up a request.  Neither option is ideal, but
+	 * GFP_KERNEL is the better choice to prevent userspace from getting an
+	 * unexpected EWOULDBLOCK.
+	 *
+	 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
+	 * does not sleep except under memory pressure.
+	 */
+	rq = blk_get_request(q, rw, GFP_KERNEL);
 	if (IS_ERR(rq)) {
 		kfree(long_cmdp);
 		return PTR_ERR(rq);
@@ -1759,10 +1785,10 @@ sg_finish_rem_req(Sg_request *srp)
 	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
 				      "sg_finish_rem_req: res_used=%d\n",
 				      (int) srp->res_used));
-	if (srp->rq) {
-		if (srp->bio)
-			ret = blk_rq_unmap_user(srp->bio);
+	if (srp->bio)
+		ret = blk_rq_unmap_user(srp->bio);
 
+	if (srp->rq) {
 		if (srp->rq->cmd != srp->rq->__cmd)
 			kfree(srp->rq->cmd);
 		blk_put_request(srp->rq);
diff --git a/drivers/scsi/wd719x.c b/drivers/scsi/wd719x.c
index 7702664..289ad01 100644
--- a/drivers/scsi/wd719x.c
+++ b/drivers/scsi/wd719x.c
@@ -870,6 +870,7 @@ fail_free_params:
 }
 
 static struct scsi_host_template wd719x_template = {
+	.module				= THIS_MODULE,
 	.name				= "Western Digital 719x",
 	.queuecommand			= wd719x_queuecommand,
 	.eh_abort_handler		= wd719x_abort,