---

yaml
---
r: 127285
b: refs/heads/master
c: 25ff1c3
h: refs/heads/master
i:
  127283: 0d428a6
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9ebd9616648bc0e47e7f8e1898c919305f1e6347
+refs/heads/master: 25ff1c316f6a763f1eefe7f8984b2d8c03888432

trunk/drivers/usb/storage/libusual.c

@@ -46,6 +46,12 @@ static int usu_probe_thread(void *arg);
 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin,bcdDeviceMax), \
   .driver_info = (flags)|(USB_US_TYPE_STOR<<24) }
 
+#define COMPLIANT_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
+		    vendorName, productName, useProtocol, useTransport, \
+		    initFunction, flags) \
+{ USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
+  .driver_info = (flags) }
+
 #define USUAL_DEV(useProto, useTrans, useType) \
 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, useProto, useTrans), \
   .driver_info = ((useType)<<24) }
@@ -57,6 +63,7 @@ struct usb_device_id storage_usb_ids [] = {
 
 #undef USUAL_DEV
 #undef UNUSUAL_DEV
+#undef COMPLIANT_DEV
 
 MODULE_DEVICE_TABLE(usb, storage_usb_ids);
 EXPORT_SYMBOL_GPL(storage_usb_ids);

trunk/drivers/usb/storage/scsiglue.c

@@ -208,6 +208,14 @@ static int slave_configure(struct scsi_device *sdev)
 		 * sector in a larger then 1 sector read, since the performance
 		 * impact is negible we set this flag for all USB disks */
 		sdev->last_sector_bug = 1;
+
+		/* Enable last-sector hacks for single-target devices using
+		 * the Bulk-only transport, unless we already know the
+		 * capacity will be decremented or is correct. */
+		if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
+					US_FL_SCM_MULT_TARG)) &&
+				us->protocol == US_PR_BULK)
+			us->use_last_sector_hacks = 1;
 	} else {
 
 		/* Non-disk-type devices don't need to blacklist any pages

trunk/drivers/usb/storage/transport.c

@@ -57,6 +57,9 @@
 #include "scsiglue.h"
 #include "debug.h"
 
+#include <linux/blkdev.h>
+#include "../../scsi/sd.h"
+
 
 /***********************************************************************
  * Data transfer routines
@@ -511,6 +514,110 @@ int usb_stor_bulk_transfer_sg(struct us_data* us, unsigned int pipe,
  * Transport routines
  ***********************************************************************/
 
+/* There are so many devices that report the capacity incorrectly,
+ * this routine was written to counteract some of the resulting
+ * problems.
+ */
+static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb)
+{
+	struct gendisk *disk;
+	struct scsi_disk *sdkp;
+	u32 sector;
+
+	/* To Report "Medium Error: Record Not Found */
+	static unsigned char record_not_found[18] = {
+		[0]	= 0x70,			/* current error */
+		[2]	= MEDIUM_ERROR,		/* = 0x03 */
+		[7]	= 0x0a,			/* additional length */
+		[12]	= 0x14			/* Record Not Found */
+	};
+
+	/* If last-sector problems can't occur, whether because the
+	 * capacity was already decremented or because the device is
+	 * known to report the correct capacity, then we don't need
+	 * to do anything.
+	 */
+	if (!us->use_last_sector_hacks)
+		return;
+
+	/* Was this command a READ(10) or a WRITE(10)? */
+	if (srb->cmnd[0] != READ_10 && srb->cmnd[0] != WRITE_10)
+		goto done;
+
+	/* Did this command access the last sector? */
+	sector = (srb->cmnd[2] << 24) | (srb->cmnd[3] << 16) |
+			(srb->cmnd[4] << 8) | (srb->cmnd[5]);
+	disk = srb->request->rq_disk;
+	if (!disk)
+		goto done;
+	sdkp = scsi_disk(disk);
+	if (!sdkp)
+		goto done;
+	if (sector + 1 != sdkp->capacity)
+		goto done;
+
+	if (srb->result == SAM_STAT_GOOD && scsi_get_resid(srb) == 0) {
+
+		/* The command succeeded.  If the capacity is odd
+		 * (i.e., if the sector number is even) then the
+		 * "always-even" heuristic would be wrong for this
+		 * device.  Issue a WARN() so that the kerneloops.org
+		 * project will be notified and we will then know to
+		 * mark the device with a CAPACITY_OK flag.  Hopefully
+		 * this will occur for only a few devices.
+		 *
+		 * Use the sign of us->last_sector_hacks to tell whether
+		 * the warning has already been issued; we don't need
+		 * more than one warning per device.
+		 */
+		if (!(sector & 1) && us->use_last_sector_hacks > 0) {
+			unsigned vid = le16_to_cpu(
+					us->pusb_dev->descriptor.idVendor);
+			unsigned pid = le16_to_cpu(
+					us->pusb_dev->descriptor.idProduct);
+			unsigned rev = le16_to_cpu(
+					us->pusb_dev->descriptor.bcdDevice);
+
+			WARN(1, "%s: Successful last sector success at %u, "
+					"device %04x:%04x:%04x\n",
+					sdkp->disk->disk_name, sector,
+					vid, pid, rev);
+			us->use_last_sector_hacks = -1;
+		}
+
+	} else {
+		/* The command failed.  Allow up to 3 retries in case this
+		 * is some normal sort of failure.  After that, assume the
+		 * capacity is wrong and we're trying to access the sector
+		 * beyond the end.  Replace the result code and sense data
+		 * with values that will cause the SCSI core to fail the
+		 * command immediately, instead of going into an infinite
+		 * (or even just a very long) retry loop.
+		 */
+		if (++us->last_sector_retries < 3)
+			return;
+		srb->result = SAM_STAT_CHECK_CONDITION;
+		memcpy(srb->sense_buffer, record_not_found,
+				sizeof(record_not_found));
+
+		/* In theory we might want to issue a WARN() here if the
+		 * capacity is even, since it could indicate the device
+		 * has the READ CAPACITY bug _and_ the real capacity is
+		 * odd.  But it could also indicate that the device
+		 * simply can't access its last sector, a failure mode
+		 * which is surprisingly common.  So no warning.
+		 */
+	}
+
+ done:
+	/* Don't reset the retry counter for TEST UNIT READY commands,
+	 * because they get issued after device resets which might be
+	 * caused by a failed last-sector access.
+	 */
+	if (srb->cmnd[0] != TEST_UNIT_READY)
+		us->last_sector_retries = 0;
+}
+
 /* Invoke the transport and basic error-handling/recovery methods
  *
  * This is used by the protocol layers to actually send the message to
@@ -544,6 +651,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 	/* if the transport provided its own sense data, don't auto-sense */
 	if (result == USB_STOR_TRANSPORT_NO_SENSE) {
 		srb->result = SAM_STAT_CHECK_CONDITION;
+		last_sector_hacks(us, srb);
 		return;
 	}
 
@@ -705,6 +813,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 			scsi_bufflen(srb) - scsi_get_resid(srb) < srb->underflow)
 		srb->result = (DID_ERROR << 16) | (SUGGEST_RETRY << 24);
 
+	last_sector_hacks(us, srb);
 	return;
 
 	/* Error and abort processing: try to resynchronize with the device
@@ -732,6 +841,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 		us->transport_reset(us);
 	}
 	clear_bit(US_FLIDX_RESETTING, &us->dflags);
+	last_sector_hacks(us, srb);
 }
 
 /* Stop the current URB transfer */

trunk/drivers/usb/storage/unusual_devs.h

@@ -27,7 +27,8 @@
 
 /* IMPORTANT NOTE: This file must be included in another file which does
  * the following thing for it to work:
- * The macro UNUSUAL_DEV() must be defined before this file is included
+ * The UNUSUAL_DEV, COMPLIANT_DEV, and USUAL_DEV macros must be defined
+ * before this file is included.
  */
 
 /* If you edit this file, please try to keep it sorted first by VendorID,
@@ -46,6 +47,12 @@
  * <usb-storage@lists.one-eyed-alien.net>
  */
 
+/* Note: If you add an entry only in order to set the CAPACITY_OK flag,
+ * use the COMPLIANT_DEV macro instead of UNUSUAL_DEV.  This is
+ * because such entries mark devices which actually work correctly,
+ * as opposed to devices that do something strangely or wrongly.
+ */
+
 /* patch submitted by Vivian Bregier <Vivian.Bregier@imag.fr>
  */
 UNUSUAL_DEV(  0x03eb, 0x2002, 0x0100, 0x0100,
@@ -704,6 +711,13 @@ UNUSUAL_DEV(  0x0525, 0xa140, 0x0100, 0x0100,
 		US_SC_8070, US_PR_DEVICE, NULL,
 		US_FL_FIX_INQUIRY ),
 
+/* Added by Alan Stern <stern@rowland.harvard.edu> */
+COMPLIANT_DEV(0x0525, 0xa4a5, 0x0000, 0x9999,
+		"Linux",
+		"File-backed Storage Gadget",
+		US_SC_DEVICE, US_PR_DEVICE, NULL,
+		US_FL_CAPACITY_OK ),
+
 /* Yakumo Mega Image 37
  * Submitted by Stephan Fuhrmann <atomenergie@t-online.de> */
 UNUSUAL_DEV(  0x052b, 0x1801, 0x0100, 0x0100,

trunk/drivers/usb/storage/usb.c

@@ -134,6 +134,8 @@ static struct quirks_entry *quirks_list, *quirks_end;
 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin,bcdDeviceMax), \
   .driver_info = (flags)|(USB_US_TYPE_STOR<<24) }
 
+#define COMPLIANT_DEV	UNUSUAL_DEV
+
 #define USUAL_DEV(useProto, useTrans, useType) \
 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, useProto, useTrans), \
   .driver_info = (USB_US_TYPE_STOR<<24) }
@@ -142,6 +144,7 @@ static struct usb_device_id storage_usb_ids [] = {
 
 #	include "unusual_devs.h"
 #undef UNUSUAL_DEV
+#undef COMPLIANT_DEV
 #undef USUAL_DEV
 	/* Terminating entry */
 	{ }
@@ -172,6 +175,8 @@ MODULE_DEVICE_TABLE (usb, storage_usb_ids);
 	.initFunction = init_function,	\
 }
 
+#define COMPLIANT_DEV	UNUSUAL_DEV
+
 #define USUAL_DEV(use_protocol, use_transport, use_type) \
 { \
 	.useProtocol = use_protocol,	\
@@ -181,6 +186,7 @@ MODULE_DEVICE_TABLE (usb, storage_usb_ids);
 static struct us_unusual_dev us_unusual_dev_list[] = {
 #	include "unusual_devs.h" 
 #	undef UNUSUAL_DEV
+#	undef COMPLIANT_DEV
 #	undef USUAL_DEV
 
 	/* Terminating entry */

trunk/drivers/usb/storage/usb.h

@@ -154,6 +154,10 @@ struct us_data {
 #ifdef CONFIG_PM
 	pm_hook			suspend_resume_hook;
 #endif
+
+	/* hacks for READ CAPACITY bug handling */
+	int			use_last_sector_hacks;
+	int			last_sector_retries;
 };
 
 /* Convert between us_data and the corresponding Scsi_Host */

trunk/include/linux/usb_usual.h

@@ -53,8 +53,10 @@
 		/* Sets max_sectors to arch min */		\
 	US_FLAG(BULK_IGNORE_TAG,0x00004000)			\
 		/* Ignore tag mismatch in bulk operations */    \
-	US_FLAG(SANE_SENSE,     0x00008000)
-		/* Sane Sense (> 18 bytes) */
+	US_FLAG(SANE_SENSE,     0x00008000)			\
+		/* Sane Sense (> 18 bytes) */			\
+	US_FLAG(CAPACITY_OK,	0x00010000)			\
+		/* READ CAPACITY response is correct */
 
 #define US_FLAG(name, value)	US_FL_##name = value ,
 enum { US_DO_ALL_FLAGS };