usb-storage: separate dynamic flags from fixed flags

This patch (as1089) separates out the dynamic atomic bitflags and the
static bitfields in usb-storage.  Until now the two sorts of flags
have been sharing the same word; this has always been awkward.

To help prevent possible confusion, the two new fields each have a
different name from the original.  us->fflags contains the fixed
bitfields (mostly taken from the USB ID table in unusual_devs.h), and
us->dflags contains the dynamic atomic bitflags (used with set_bit,
test_bit, and so on).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/storage/isd200.c

@@ -586,7 +586,7 @@ static void isd200_invoke_transport( struct us_data *us,
 	/* if the command gets aborted by the higher layers, we need to
 	 * short-circuit all other processing
 	 */
-	if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
+	if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
 		US_DEBUGP("-- command was aborted\n");
 		goto Handle_Abort;
 	}
@@ -633,7 +633,7 @@ static void isd200_invoke_transport( struct us_data *us,
 
 	if (need_auto_sense) {
 		result = isd200_read_regs(us);
-		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
+		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
 			US_DEBUGP("-- auto-sense aborted\n");
 			goto Handle_Abort;
 		}
@@ -663,7 +663,7 @@ static void isd200_invoke_transport( struct us_data *us,
 	srb->result = DID_ABORT << 16;
 
 	/* permit the reset transfer to take place */
-	clear_bit(US_FLIDX_ABORTING, &us->flags);
+	clear_bit(US_FLIDX_ABORTING, &us->dflags);
 	/* Need reset here */
 }
 

drivers/usb/storage/scsiglue.c

@@ -116,10 +116,10 @@ static int slave_configure(struct scsi_device *sdev)
 	 * while others have trouble with more than 64K. At this time we
 	 * are limiting both to 32K (64 sectores).
 	 */
-	if (us->flags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
+	if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
 		unsigned int max_sectors = 64;
 
-		if (us->flags & US_FL_MAX_SECTORS_MIN)
+		if (us->fflags & US_FL_MAX_SECTORS_MIN)
 			max_sectors = PAGE_CACHE_SIZE >> 9;
 		if (sdev->request_queue->max_sectors > max_sectors)
 			blk_queue_max_sectors(sdev->request_queue,
@@ -148,7 +148,7 @@ static int slave_configure(struct scsi_device *sdev)
 		 * majority of devices work fine, but a few still can't
 		 * handle it.  The sd driver will simply assume those
 		 * devices are write-enabled. */
-		if (us->flags & US_FL_NO_WP_DETECT)
+		if (us->fflags & US_FL_NO_WP_DETECT)
 			sdev->skip_ms_page_3f = 1;
 
 		/* A number of devices have problems with MODE SENSE for
@@ -158,13 +158,13 @@ static int slave_configure(struct scsi_device *sdev)
 		/* Some disks return the total number of blocks in response
 		 * to READ CAPACITY rather than the highest block number.
 		 * If this device makes that mistake, tell the sd driver. */
-		if (us->flags & US_FL_FIX_CAPACITY)
+		if (us->fflags & US_FL_FIX_CAPACITY)
 			sdev->fix_capacity = 1;
 
 		/* A few disks have two indistinguishable version, one of
 		 * which reports the correct capacity and the other does not.
 		 * The sd driver has to guess which is the case. */
-		if (us->flags & US_FL_CAPACITY_HEURISTICS)
+		if (us->fflags & US_FL_CAPACITY_HEURISTICS)
 			sdev->guess_capacity = 1;
 
 		/* Some devices report a SCSI revision level above 2 but are
@@ -213,7 +213,7 @@ static int slave_configure(struct scsi_device *sdev)
 
 	/* Some devices choke when they receive a PREVENT-ALLOW MEDIUM
 	 * REMOVAL command, so suppress those commands. */
-	if (us->flags & US_FL_NOT_LOCKABLE)
+	if (us->fflags & US_FL_NOT_LOCKABLE)
 		sdev->lockable = 0;
 
 	/* this is to satisfy the compiler, tho I don't think the 
@@ -238,7 +238,7 @@ static int queuecommand(struct scsi_cmnd *srb,
 	}
 
 	/* fail the command if we are disconnecting */
-	if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+	if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
 		US_DEBUGP("Fail command during disconnect\n");
 		srb->result = DID_NO_CONNECT << 16;
 		done(srb);
@@ -280,9 +280,9 @@ static int command_abort(struct scsi_cmnd *srb)
 	 * with the reset).  Note that we must retain the host lock while
 	 * calling usb_stor_stop_transport(); otherwise it might interfere
 	 * with an auto-reset that begins as soon as we release the lock. */
-	set_bit(US_FLIDX_TIMED_OUT, &us->flags);
-	if (!test_bit(US_FLIDX_RESETTING, &us->flags)) {
-		set_bit(US_FLIDX_ABORTING, &us->flags);
+	set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
+	if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
+		set_bit(US_FLIDX_ABORTING, &us->dflags);
 		usb_stor_stop_transport(us);
 	}
 	scsi_unlock(us_to_host(us));
@@ -329,7 +329,7 @@ void usb_stor_report_device_reset(struct us_data *us)
 	struct Scsi_Host *host = us_to_host(us);
 
 	scsi_report_device_reset(host, 0, 0);
-	if (us->flags & US_FL_SCM_MULT_TARG) {
+	if (us->fflags & US_FL_SCM_MULT_TARG) {
 		for (i = 1; i < host->max_id; ++i)
 			scsi_report_device_reset(host, 0, i);
 	}
@@ -400,7 +400,7 @@ static int proc_info (struct Scsi_Host *host, char *buffer,
 		pos += sprintf(pos, "       Quirks:");
 
 #define US_FLAG(name, value) \
-	if (us->flags & value) pos += sprintf(pos, " " #name);
+	if (us->fflags & value) pos += sprintf(pos, " " #name);
 US_DO_ALL_FLAGS
 #undef US_FLAG
 

drivers/usb/storage/transport.c

@@ -75,14 +75,14 @@
  * by a separate code path.)
  *
  * The abort function (usb_storage_command_abort() in scsiglue.c) first
- * sets the machine state and the ABORTING bit in us->flags to prevent
+ * sets the machine state and the ABORTING bit in us->dflags to prevent
  * new URBs from being submitted.  It then calls usb_stor_stop_transport()
- * below, which atomically tests-and-clears the URB_ACTIVE bit in us->flags
+ * below, which atomically tests-and-clears the URB_ACTIVE bit in us->dflags
  * to see if the current_urb needs to be stopped.  Likewise, the SG_ACTIVE
  * bit is tested to see if the current_sg scatter-gather request needs to be
  * stopped.  The timeout callback routine does much the same thing.
  *
- * When a disconnect occurs, the DISCONNECTING bit in us->flags is set to
+ * When a disconnect occurs, the DISCONNECTING bit in us->dflags is set to
  * prevent new URBs from being submitted, and usb_stor_stop_transport() is
  * called to stop any ongoing requests.
  *
@@ -128,7 +128,7 @@ static int usb_stor_msg_common(struct us_data *us, int timeout)
 	int status;
 
 	/* don't submit URBs during abort/disconnect processing */
-	if (us->flags & ABORTING_OR_DISCONNECTING)
+	if (us->dflags & ABORTING_OR_DISCONNECTING)
 		return -EIO;
 
 	/* set up data structures for the wakeup system */
@@ -159,13 +159,13 @@ static int usb_stor_msg_common(struct us_data *us, int timeout)
 
 	/* since the URB has been submitted successfully, it's now okay
 	 * to cancel it */
-	set_bit(US_FLIDX_URB_ACTIVE, &us->flags);
+	set_bit(US_FLIDX_URB_ACTIVE, &us->dflags);
 
 	/* did an abort/disconnect occur during the submission? */
-	if (us->flags & ABORTING_OR_DISCONNECTING) {
+	if (us->dflags & ABORTING_OR_DISCONNECTING) {
 
 		/* cancel the URB, if it hasn't been cancelled already */
-		if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->flags)) {
+		if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) {
 			US_DEBUGP("-- cancelling URB\n");
 			usb_unlink_urb(us->current_urb);
 		}
@@ -175,7 +175,7 @@ static int usb_stor_msg_common(struct us_data *us, int timeout)
 	timeleft = wait_for_completion_interruptible_timeout(
 			&urb_done, timeout ? : MAX_SCHEDULE_TIMEOUT);
  
-	clear_bit(US_FLIDX_URB_ACTIVE, &us->flags);
+	clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags);
 
 	if (timeleft <= 0) {
 		US_DEBUGP("%s -- cancelling URB\n",
@@ -420,7 +420,7 @@ static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
 	int result;
 
 	/* don't submit s-g requests during abort/disconnect processing */
-	if (us->flags & ABORTING_OR_DISCONNECTING)
+	if (us->dflags & ABORTING_OR_DISCONNECTING)
 		return USB_STOR_XFER_ERROR;
 
 	/* initialize the scatter-gather request block */
@@ -435,13 +435,13 @@ static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
 
 	/* since the block has been initialized successfully, it's now
 	 * okay to cancel it */
-	set_bit(US_FLIDX_SG_ACTIVE, &us->flags);
+	set_bit(US_FLIDX_SG_ACTIVE, &us->dflags);
 
 	/* did an abort/disconnect occur during the submission? */
-	if (us->flags & ABORTING_OR_DISCONNECTING) {
+	if (us->dflags & ABORTING_OR_DISCONNECTING) {
 
 		/* cancel the request, if it hasn't been cancelled already */
-		if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->flags)) {
+		if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) {
 			US_DEBUGP("-- cancelling sg request\n");
 			usb_sg_cancel(&us->current_sg);
 		}
@@ -449,7 +449,7 @@ static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
 
 	/* wait for the completion of the transfer */
 	usb_sg_wait(&us->current_sg);
-	clear_bit(US_FLIDX_SG_ACTIVE, &us->flags);
+	clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags);
 
 	result = us->current_sg.status;
 	if (act_len)
@@ -530,7 +530,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 	/* if the command gets aborted by the higher layers, we need to
 	 * short-circuit all other processing
 	 */
-	if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
+	if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
 		US_DEBUGP("-- command was aborted\n");
 		srb->result = DID_ABORT << 16;
 		goto Handle_Errors;
@@ -616,7 +616,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 		/* let's clean up right away */
 		scsi_eh_restore_cmnd(srb, &ses);
 
-		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
+		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
 			US_DEBUGP("-- auto-sense aborted\n");
 			srb->result = DID_ABORT << 16;
 			goto Handle_Errors;
@@ -629,7 +629,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 			 * auto-sense is perfectly valid
 			 */
 			srb->result = DID_ERROR << 16;
-			if (!(us->flags & US_FL_SCM_MULT_TARG))
+			if (!(us->fflags & US_FL_SCM_MULT_TARG))
 				goto Handle_Errors;
 			return;
 		}
@@ -679,8 +679,8 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 	/* Set the RESETTING bit, and clear the ABORTING bit so that
 	 * the reset may proceed. */
 	scsi_lock(us_to_host(us));
-	set_bit(US_FLIDX_RESETTING, &us->flags);
-	clear_bit(US_FLIDX_ABORTING, &us->flags);
+	set_bit(US_FLIDX_RESETTING, &us->dflags);
+	clear_bit(US_FLIDX_ABORTING, &us->dflags);
 	scsi_unlock(us_to_host(us));
 
 	/* We must release the device lock because the pre_reset routine
@@ -695,7 +695,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 		scsi_unlock(us_to_host(us));
 		us->transport_reset(us);
 	}
-	clear_bit(US_FLIDX_RESETTING, &us->flags);
+	clear_bit(US_FLIDX_RESETTING, &us->dflags);
 }
 
 /* Stop the current URB transfer */
@@ -707,13 +707,13 @@ void usb_stor_stop_transport(struct us_data *us)
 	 * let's wake it up.  The test_and_clear_bit() call
 	 * guarantees that if a URB has just been submitted,
 	 * it won't be cancelled more than once. */
-	if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->flags)) {
+	if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) {
 		US_DEBUGP("-- cancelling URB\n");
 		usb_unlink_urb(us->current_urb);
 	}
 
 	/* If we are waiting for a scatter-gather operation, cancel it. */
-	if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->flags)) {
+	if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) {
 		US_DEBUGP("-- cancelling sg request\n");
 		usb_sg_cancel(&us->current_sg);
 	}
@@ -914,7 +914,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
 	unsigned int cbwlen = US_BULK_CB_WRAP_LEN;
 
 	/* Take care of BULK32 devices; set extra byte to 0 */
-	if ( unlikely(us->flags & US_FL_BULK32)) {
+	if (unlikely(us->fflags & US_FL_BULK32)) {
 		cbwlen = 32;
 		us->iobuf[31] = 0;
 	}
@@ -925,7 +925,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
 	bcb->Flags = srb->sc_data_direction == DMA_FROM_DEVICE ? 1 << 7 : 0;
 	bcb->Tag = ++us->tag;
 	bcb->Lun = srb->device->lun;
-	if (us->flags & US_FL_SCM_MULT_TARG)
+	if (us->fflags & US_FL_SCM_MULT_TARG)
 		bcb->Lun |= srb->device->id << 4;
 	bcb->Length = srb->cmd_len;
 
@@ -951,7 +951,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
 	/* Some USB-IDE converter chips need a 100us delay between the
 	 * command phase and the data phase.  Some devices need a little
 	 * more than that, probably because of clock rate inaccuracies. */
-	if (unlikely(us->flags & US_FL_GO_SLOW))
+	if (unlikely(us->fflags & US_FL_GO_SLOW))
 		udelay(125);
 
 	if (transfer_length) {
@@ -1010,7 +1010,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
 	US_DEBUGP("Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n",
 			le32_to_cpu(bcs->Signature), bcs->Tag, 
 			residue, bcs->Status);
-	if (!(bcs->Tag == us->tag || (us->flags & US_FL_BULK_IGNORE_TAG)) ||
+	if (!(bcs->Tag == us->tag || (us->fflags & US_FL_BULK_IGNORE_TAG)) ||
 		bcs->Status > US_BULK_STAT_PHASE) {
 		US_DEBUGP("Bulk logical error\n");
 		return USB_STOR_TRANSPORT_ERROR;
@@ -1035,7 +1035,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
 	/* try to compute the actual residue, based on how much data
 	 * was really transferred and what the device tells us */
 	if (residue) {
-		if (!(us->flags & US_FL_IGNORE_RESIDUE)) {
+		if (!(us->fflags & US_FL_IGNORE_RESIDUE)) {
 			residue = min(residue, transfer_length);
 			scsi_set_resid(srb, max(scsi_get_resid(srb),
 			                                       (int) residue));
@@ -1090,7 +1090,7 @@ static int usb_stor_reset_common(struct us_data *us,
 	int result;
 	int result2;
 
-	if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+	if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
 		US_DEBUGP("No reset during disconnect\n");
 		return -EIO;
 	}
@@ -1103,12 +1103,12 @@ static int usb_stor_reset_common(struct us_data *us,
 		return result;
 	}
 
- 	/* Give the device some time to recover from the reset,
- 	 * but don't delay disconnect processing. */
- 	wait_event_interruptible_timeout(us->delay_wait,
- 			test_bit(US_FLIDX_DISCONNECTING, &us->flags),
- 			HZ*6);
-	if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+	/* Give the device some time to recover from the reset,
+	 * but don't delay disconnect processing. */
+	wait_event_interruptible_timeout(us->delay_wait,
+			test_bit(US_FLIDX_DISCONNECTING, &us->dflags),
+			HZ*6);
+	if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
 		US_DEBUGP("Reset interrupted by disconnect\n");
 		return -EIO;
 	}
@@ -1170,7 +1170,7 @@ int usb_stor_port_reset(struct us_data *us)
 		US_DEBUGP("unable to lock device for reset: %d\n", result);
 	else {
 		/* Were we disconnected while waiting for the lock? */
-		if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+		if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
 			result = -EIO;
 			US_DEBUGP("No reset during disconnect\n");
 		} else {

drivers/usb/storage/usb.c

@@ -321,7 +321,7 @@ static int usb_stor_control_thread(void * __us)
 		mutex_lock(&(us->dev_mutex));
 
 		/* if the device has disconnected, we are free to exit */
-		if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+		if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
 			US_DEBUGP("-- exiting\n");
 			mutex_unlock(&us->dev_mutex);
 			break;
@@ -331,7 +331,7 @@ static int usb_stor_control_thread(void * __us)
 		scsi_lock(host);
 
 		/* has the command timed out *already* ? */
-		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
+		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
 			us->srb->result = DID_ABORT << 16;
 			goto SkipForAbort;
 		}
@@ -350,7 +350,7 @@ static int usb_stor_control_thread(void * __us)
 		 * the maximum known LUN
 		 */
 		else if (us->srb->device->id && 
-				!(us->flags & US_FL_SCM_MULT_TARG)) {
+				!(us->fflags & US_FL_SCM_MULT_TARG)) {
 			US_DEBUGP("Bad target number (%d:%d)\n",
 				  us->srb->device->id, us->srb->device->lun);
 			us->srb->result = DID_BAD_TARGET << 16;
@@ -365,7 +365,7 @@ static int usb_stor_control_thread(void * __us)
 		/* Handle those devices which need us to fake 
 		 * their inquiry data */
 		else if ((us->srb->cmnd[0] == INQUIRY) &&
-			    (us->flags & US_FL_FIX_INQUIRY)) {
+			    (us->fflags & US_FL_FIX_INQUIRY)) {
 			unsigned char data_ptr[36] = {
 			    0x00, 0x80, 0x02, 0x02,
 			    0x1F, 0x00, 0x00, 0x00};
@@ -403,12 +403,12 @@ static int usb_stor_control_thread(void * __us)
 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
 		 * the timeout might have occurred after the command had
 		 * already completed with a different result code. */
-		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
+		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
 			complete(&(us->notify));
 
 			/* Allow USB transfers to resume */
-			clear_bit(US_FLIDX_ABORTING, &us->flags);
-			clear_bit(US_FLIDX_TIMED_OUT, &us->flags);
+			clear_bit(US_FLIDX_ABORTING, &us->dflags);
+			clear_bit(US_FLIDX_TIMED_OUT, &us->dflags);
 		}
 
 		/* finished working on this command */
@@ -500,9 +500,9 @@ static int get_device_info(struct us_data *us, const struct usb_device_id *id)
 	us->protocol = (unusual_dev->useTransport == US_PR_DEVICE) ?
 			idesc->bInterfaceProtocol :
 			unusual_dev->useTransport;
-	us->flags = USB_US_ORIG_FLAGS(id->driver_info);
+	us->fflags = USB_US_ORIG_FLAGS(id->driver_info);
 
-	if (us->flags & US_FL_IGNORE_DEVICE) {
+	if (us->fflags & US_FL_IGNORE_DEVICE) {
 		printk(KERN_INFO USB_STORAGE "device ignored\n");
 		return -ENODEV;
 	}
@@ -512,7 +512,7 @@ static int get_device_info(struct us_data *us, const struct usb_device_id *id)
 	 * disable it if we're in full-speed
 	 */
 	if (dev->speed != USB_SPEED_HIGH)
-		us->flags &= ~US_FL_GO_SLOW;
+		us->fflags &= ~US_FL_GO_SLOW;
 
 	/* Log a message if a non-generic unusual_dev entry contains an
 	 * unnecessary subclass or protocol override.  This may stimulate
@@ -533,7 +533,7 @@ static int get_device_info(struct us_data *us, const struct usb_device_id *id)
 		if (unusual_dev->useTransport != US_PR_DEVICE &&
 			us->protocol == idesc->bInterfaceProtocol)
 			msg += 2;
-		if (msg >= 0 && !(us->flags & US_FL_NEED_OVERRIDE))
+		if (msg >= 0 && !(us->fflags & US_FL_NEED_OVERRIDE))
 			printk(KERN_NOTICE USB_STORAGE "This device "
 				"(%04x,%04x,%04x S %02x P %02x)"
 				" has %s in unusual_devs.h (kernel"
@@ -663,7 +663,7 @@ static int get_transport(struct us_data *us)
 	US_DEBUGP("Transport: %s\n", us->transport_name);
 
 	/* fix for single-lun devices */
-	if (us->flags & US_FL_SINGLE_LUN)
+	if (us->fflags & US_FL_SINGLE_LUN)
 		us->max_lun = 0;
 	return 0;
 }
@@ -824,7 +824,7 @@ static void usb_stor_release_resources(struct us_data *us)
 	 * any more commands.
 	 */
 	US_DEBUGP("-- sending exit command to thread\n");
-	set_bit(US_FLIDX_DISCONNECTING, &us->flags);
+	set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
 	up(&us->sema);
 	if (us->ctl_thread)
 		kthread_stop(us->ctl_thread);
@@ -868,7 +868,7 @@ static void quiesce_and_remove_host(struct us_data *us)
 	/* Prevent new USB transfers, stop the current command, and
 	 * interrupt a SCSI-scan or device-reset delay */
 	scsi_lock(host);
-	set_bit(US_FLIDX_DISCONNECTING, &us->flags);
+	set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
 	scsi_unlock(host);
 	usb_stor_stop_transport(us);
 	wake_up(&us->delay_wait);
@@ -919,16 +919,16 @@ static int usb_stor_scan_thread(void * __us)
 		printk(KERN_DEBUG "usb-storage: waiting for device "
 				"to settle before scanning\n");
 		wait_event_freezable_timeout(us->delay_wait,
-				test_bit(US_FLIDX_DISCONNECTING, &us->flags),
+				test_bit(US_FLIDX_DISCONNECTING, &us->dflags),
 				delay_use * HZ);
 	}
 
 	/* If the device is still connected, perform the scanning */
-	if (!test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+	if (!test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
 
 		/* For bulk-only devices, determine the max LUN value */
 		if (us->protocol == US_PR_BULK &&
-				!(us->flags & US_FL_SINGLE_LUN)) {
+				!(us->fflags & US_FL_SINGLE_LUN)) {
 			mutex_lock(&us->dev_mutex);
 			us->max_lun = usb_stor_Bulk_max_lun(us);
 			mutex_unlock(&us->dev_mutex);

drivers/usb/storage/usb.h

@@ -67,15 +67,15 @@ struct us_unusual_dev {
 };
 
 
-/* Dynamic flag definitions: used in set_bit() etc. */
-#define US_FLIDX_URB_ACTIVE	18  /* 0x00040000  current_urb is in use  */
-#define US_FLIDX_SG_ACTIVE	19  /* 0x00080000  current_sg is in use   */
-#define US_FLIDX_ABORTING	20  /* 0x00100000  abort is in progress   */
-#define US_FLIDX_DISCONNECTING	21  /* 0x00200000  disconnect in progress */
+/* Dynamic bitflag definitions (us->dflags): used in set_bit() etc. */
+#define US_FLIDX_URB_ACTIVE	0	/* current_urb is in use    */
+#define US_FLIDX_SG_ACTIVE	1	/* current_sg is in use     */
+#define US_FLIDX_ABORTING	2	/* abort is in progress     */
+#define US_FLIDX_DISCONNECTING	3	/* disconnect in progress   */
 #define ABORTING_OR_DISCONNECTING	((1UL << US_FLIDX_ABORTING) | \
 					 (1UL << US_FLIDX_DISCONNECTING))
-#define US_FLIDX_RESETTING	22  /* 0x00400000  device reset in progress */
-#define US_FLIDX_TIMED_OUT	23  /* 0x00800000  SCSI midlayer timed out  */
+#define US_FLIDX_RESETTING	4	/* device reset in progress */
+#define US_FLIDX_TIMED_OUT	5	/* SCSI midlayer timed out  */
 
 
 #define USB_STOR_STRING_LEN 32
@@ -109,7 +109,8 @@ struct us_data {
 	struct usb_device	*pusb_dev;	 /* this usb_device */
 	struct usb_interface	*pusb_intf;	 /* this interface */
 	struct us_unusual_dev   *unusual_dev;	 /* device-filter entry     */
-	unsigned long		flags;		 /* from filter initially */
+	unsigned long		fflags;		 /* fixed flags from filter */
+	unsigned long		dflags;		 /* dynamic atomic bitflags */
 	unsigned int		send_bulk_pipe;	 /* cached pipe values */
 	unsigned int		recv_bulk_pipe;
 	unsigned int		send_ctrl_pipe;