uas: Add US_FL_MAX_SECTORS_240 flag

The usb-storage driver sets max_sectors = 240 in its scsi-host template,
for uas we do not want to do that for all devices, but testing has shown
that some devices need it.

This commit adds a US_FL_MAX_SECTORS_240 flag for such devices, and
implements support for it in uas.c, while at it it also adds support
for US_FL_MAX_SECTORS_64 to uas.c.

Cc: stable@vger.kernel.org # 3.16
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index c6109c1..6d3122a 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -759,7 +759,10 @@
 
 static int uas_slave_alloc(struct scsi_device *sdev)
 {
-	sdev->hostdata = (void *)sdev->host->hostdata;
+	struct uas_dev_info *devinfo =
+		(struct uas_dev_info *)sdev->host->hostdata;
+
+	sdev->hostdata = devinfo;
 
 	/* USB has unusual DMA-alignment requirements: Although the
 	 * starting address of each scatter-gather element doesn't matter,
@@ -778,6 +781,11 @@
 	 */
 	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;
 }