scsi: communicate max segment size to the DMA mapping code

When a host driver sets a maximum segment size we should not only propagate
that setting to the block layer, which can merge segments, but also to the
DMA mapping layer which can merge segments as well.

Fixes: 50c2e9107f ("scsi: introduce a max_segment_size host_template parameters")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

5 files changed, 20 insertions, 29 deletions

diff --git a/drivers/ata/pata_macio.c b/drivers/ata/pata_macio.c
index 8cc9c429ad95..9e7fc302430f 100644
--- a/drivers/ata/pata_macio.c
+++ b/drivers/ata/pata_macio.c
@@ -915,6 +915,10 @@ static struct scsi_host_template pata_macio_sht = {
 	.sg_tablesize		= MAX_DCMDS,
 	/* We may not need that strict one */
 	.dma_boundary		= ATA_DMA_BOUNDARY,
+	/* Not sure what the real max is but we know it's less than 64K, let's
+	 * use 64K minus 256
+	 */
+	.max_segment_size	= MAX_DBDMA_SEG,
 	.slave_configure	= pata_macio_slave_config,
 };
 
@@ -1044,11 +1048,6 @@ static int pata_macio_common_init(struct pata_macio_priv *priv,
 	/* Make sure we have sane initial timings in the cache */
 	pata_macio_default_timings(priv);
 
-	/* Not sure what the real max is but we know it's less than 64K, let's
-	 * use 64K minus 256
-	 */
-	dma_set_max_seg_size(priv->dev, MAX_DBDMA_SEG);
-
 	/* Allocate libata host for 1 port */
 	memset(&pinfo, 0, sizeof(struct ata_port_info));
 	pmac_macio_calc_timing_masks(priv, &pinfo);
diff --git a/drivers/ata/sata_inic162x.c b/drivers/ata/sata_inic162x.c
index e0bcf9b2dab0..174e84ce4379 100644
--- a/drivers/ata/sata_inic162x.c
+++ b/drivers/ata/sata_inic162x.c
@@ -245,8 +245,15 @@ struct inic_port_priv {
 
 static struct scsi_host_template inic_sht = {
 	ATA_BASE_SHT(DRV_NAME),
-	.sg_tablesize	= LIBATA_MAX_PRD,	/* maybe it can be larger? */
-	.dma_boundary	= INIC_DMA_BOUNDARY,
+	.sg_tablesize		= LIBATA_MAX_PRD, /* maybe it can be larger? */
+
+	/*
+	 * This controller is braindamaged.  dma_boundary is 0xffff like others
+	 * but it will lock up the whole machine HARD if 65536 byte PRD entry
+	 * is fed.  Reduce maximum segment size.
+	 */
+	.dma_boundary		= INIC_DMA_BOUNDARY,
+	.max_segment_size	= 65536 - 512,
 };
 
 static const int scr_map[] = {
@@ -868,17 +875,6 @@ static int inic_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		return rc;
 	}
 
-	/*
-	 * This controller is braindamaged.  dma_boundary is 0xffff
-	 * like others but it will lock up the whole machine HARD if
-	 * 65536 byte PRD entry is fed. Reduce maximum segment size.
-	 */
-	rc = dma_set_max_seg_size(&pdev->dev, 65536 - 512);
-	if (rc) {
-		dev_err(&pdev->dev, "failed to set the maximum segment size\n");
-		return rc;
-	}
-
 	rc = init_controller(hpriv->mmio_base, hpriv->cached_hctl);
 	if (rc) {
 		dev_err(&pdev->dev, "failed to initialize controller\n");
diff --git a/drivers/firewire/sbp2.c b/drivers/firewire/sbp2.c
index 09b845e90114..a785ffd5af89 100644
--- a/drivers/firewire/sbp2.c
+++ b/drivers/firewire/sbp2.c
@@ -1144,10 +1144,6 @@ static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
 	if (device->is_local)
 		return -ENODEV;
 
-	if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
-		WARN_ON(dma_set_max_seg_size(device->card->device,
-					     SBP2_MAX_SEG_SIZE));
-
 	shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
 	if (shost == NULL)
 		return -ENOMEM;
@@ -1610,6 +1606,7 @@ static struct scsi_host_template scsi_driver_template = {
 	.eh_abort_handler	= sbp2_scsi_abort,
 	.this_id		= -1,
 	.sg_tablesize		= SG_ALL,
+	.max_segment_size	= SBP2_MAX_SEG_SIZE,
 	.can_queue		= 1,
 	.sdev_attrs		= sbp2_scsi_sysfs_attrs,
 };
diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
index 634ddb90e7aa..7e56a11836c1 100644
--- a/drivers/scsi/aacraid/linit.c
+++ b/drivers/scsi/aacraid/linit.c
@@ -1747,11 +1747,10 @@ static int aac_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
 		shost->max_sectors = (shost->sg_tablesize * 8) + 112;
 	}
 
-	error = dma_set_max_seg_size(&pdev->dev,
-		(aac->adapter_info.options & AAC_OPT_NEW_COMM) ?
-			(shost->max_sectors << 9) : 65536);
-	if (error)
-		goto out_deinit;
+	if (aac->adapter_info.options & AAC_OPT_NEW_COMM)
+		shost->max_segment_size = shost->max_sectors << 9;
+	else
+		shost->max_segment_size = 65536;
 
 	/*
 	 * Firmware printf works only with older firmware.
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index b13cc9288ba0..6d65ac584eba 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1842,8 +1842,8 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
 	blk_queue_segment_boundary(q, shost->dma_boundary);
 	dma_set_seg_boundary(dev, shost->dma_boundary);
 
-	blk_queue_max_segment_size(q,
-		min(shost->max_segment_size, dma_get_max_seg_size(dev)));
+	blk_queue_max_segment_size(q, shost->max_segment_size);
+	dma_set_max_seg_size(dev, shost->max_segment_size);
 
 	/*
 	 * Set a reasonable default alignment:  The larger of 32-byte (dword),