uas: fix sdev->host->dma_dev

Use scsi_add_host_with_dma() instead of scsi_add_host().

When the scsi request queue is initialized/allocated, hw_max_sectors is clamped
to the dma max mapping size. Therefore, the correct device that should be used
for the clamping needs to be set.

The same clamping is still needed in uas as hw_max_sectors could be changed
there. The original clamping would be invalidated in such cases.

Signed-off-by: Tom Yan <tom.ty89@gmail.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20200903181725.2931-2-tom.ty89@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/storage/uas.c

@@ -827,17 +827,22 @@ static int uas_slave_alloc(struct scsi_device *sdev)
 	 */
 	blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
 
-	if (devinfo->flags & US_FL_MAX_SECTORS_64)
-		blk_queue_max_hw_sectors(sdev->request_queue, 64);
-	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
-		blk_queue_max_hw_sectors(sdev->request_queue, 240);
-
 	return 0;
 }
 
 static int uas_slave_configure(struct scsi_device *sdev)
 {
 	struct uas_dev_info *devinfo = sdev->hostdata;
+	struct device *dev = sdev->host->dma_dev;
+
+	if (devinfo->flags & US_FL_MAX_SECTORS_64)
+		blk_queue_max_hw_sectors(sdev->request_queue, 64);
+	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
+		blk_queue_max_hw_sectors(sdev->request_queue, 240);
+
+	blk_queue_max_hw_sectors(sdev->request_queue,
+		min_t(size_t, queue_max_hw_sectors(sdev->request_queue),
+		      dma_max_mapping_size(dev) >> SECTOR_SHIFT));
 
 	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
 		sdev->no_report_opcodes = 1;
@@ -1023,7 +1028,7 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	shost->can_queue = devinfo->qdepth - 2;
 
 	usb_set_intfdata(intf, shost);
-	result = scsi_add_host(shost, &intf->dev);
+	result = scsi_add_host_with_dma(shost, &intf->dev, udev->bus->sysdev);
 	if (result)
 		goto free_streams;