[PATCH 4.0 52/72] uas: Add US_FL_MAX_SECTORS_240 flag

Greg Kroah-Hartman
2015-05-11T17:56:22Z

From: Hans de Goede <hdegoede@redhat.com>

commit ee136af4a064c2f61e2025873584d2c7ec93f4ae upstream.

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.

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>

---
Documentation/kernel-parameters.txt | 2 ++
drivers/usb/storage/uas.c | 10 +++++++++-
drivers/usb/storage/usb.c | 6 +++++-
include/linux/usb_usual.h | 2 ++
4 files changed, 18 insertions(+), 2 deletions(-)

--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3746,6 +3746,8 @@ bytes respectively. Such letter suffixes
READ_CAPACITY_16 command);
f = NO_REPORT_OPCODES (don't use report opcodes
command, uas only);
+ g = MAX_SECTORS_240 (don't transfer more than
+ 240 sectors at a time, uas only);
h = CAPACITY_HEURISTICS (decrease the
reported device capacity by one
sector if the number is odd);
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -759,7 +759,10 @@ static int uas_eh_bus_reset_handler(stru

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 @@ static int uas_slave_alloc(struct scsi_d
*/
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;
}

--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -479,7 +479,8 @@ void usb_stor_adjust_quirks(struct usb_d
US_FL_SINGLE_LUN | US_FL_NO_WP_DETECT |
US_FL_NO_READ_DISC_INFO | US_FL_NO_READ_CAPACITY_16 |
US_FL_INITIAL_READ10 | US_FL_WRITE_CACHE |
- US_FL_NO_ATA_1X | US_FL_NO_REPORT_OPCODES);
+ US_FL_NO_ATA_1X | US_FL_NO_REPORT_OPCODES |
+ US_FL_MAX_SECTORS_240);

p = quirks;
while (*p) {
@@ -520,6 +521,9 @@ void usb_stor_adjust_quirks(struct usb_d
case 'f':
f |= US_FL_NO_REPORT_OPCODES;
break;
+ case 'g':
+ f |= US_FL_MAX_SECTORS_240;
+ break;
case 'h':
f |= US_FL_CAPACITY_HEURISTICS;
break;
--- a/include/linux/usb_usual.h
+++ b/include/linux/usb_usual.h
@@ -77,6 +77,8 @@
/* Cannot handle ATA_12 or ATA_16 CDBs */ \
US_FLAG(NO_REPORT_OPCODES, 0x04000000) \
/* Cannot handle MI_REPORT_SUPPORTED_OPERATION_CODES */ \
+ US_FLAG(MAX_SECTORS_240, 0x08000000) \
+ /* Sets max_sectors to 240 */ \

#define US_FLAG(name, value) US_FL_##name = value ,
enum { US_DO_ALL_FLAGS };