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Merge 3.2-rc1 into usb-linus

This is needed to catch the resume bug that was bothering lots of us from
testing some XHCI bug fixes in the suspend/resume path.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Greg Kroah-Hartman 13 years ago
parent
commit
e3fa252a0e

+ 22 - 0
Documentation/usb/URB.txt

@@ -168,6 +168,28 @@ that if the completion handler or anyone else tries to resubmit it
 they will get a -EPERM error.  Thus you can be sure that when
 usb_kill_urb() returns, the URB is totally idle.
 
+There is a lifetime issue to consider.  An URB may complete at any
+time, and the completion handler may free the URB.  If this happens
+while usb_unlink_urb or usb_kill_urb is running, it will cause a
+memory-access violation.  The driver is responsible for avoiding this,
+which often means some sort of lock will be needed to prevent the URB
+from being deallocated while it is still in use.
+
+On the other hand, since usb_unlink_urb may end up calling the
+completion handler, the handler must not take any lock that is held
+when usb_unlink_urb is invoked.  The general solution to this problem
+is to increment the URB's reference count while holding the lock, then
+drop the lock and call usb_unlink_urb or usb_kill_urb, and then
+decrement the URB's reference count.  You increment the reference
+count by calling
+
+	struct urb *usb_get_urb(struct urb *urb)
+
+(ignore the return value; it is the same as the argument) and
+decrement the reference count by calling usb_free_urb.  Of course,
+none of this is necessary if there's no danger of the URB being freed
+by the completion handler.
+
 
 1.7. What about the completion handler?
 

+ 3 - 3
Documentation/usb/usbmon.txt

@@ -183,10 +183,10 @@ An input control transfer to get a port status.
 d5ea89a0 3575914555 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
 d5ea89a0 3575914560 C Ci:1:001:0 0 4 = 01050000
 
-An output bulk transfer to send a SCSI command 0x5E in a 31-byte Bulk wrapper
-to a storage device at address 5:
+An output bulk transfer to send a SCSI command 0x28 (READ_10) in a 31-byte
+Bulk wrapper to a storage device at address 5:
 
-dd65f0e8 4128379752 S Bo:1:005:2 -115 31 = 55534243 5e000000 00000000 00000600 00000000 00000000 00000000 000000
+dd65f0e8 4128379752 S Bo:1:005:2 -115 31 = 55534243 ad000000 00800000 80010a28 20000000 20000040 00000000 000000
 dd65f0e8 4128379808 C Bo:1:005:2 0 31 >
 
 * Raw binary format and API

+ 8 - 8
drivers/usb/Kconfig

@@ -2,14 +2,6 @@
 # USB device configuration
 #
 
-menuconfig USB_SUPPORT
-	bool "USB support"
-	depends on HAS_IOMEM
-	default y
-	---help---
-	  This option adds core support for Universal Serial Bus (USB).
-	  You will also need drivers from the following menu to make use of it.
-
 # many non-PCI SOC chips embed OHCI
 config USB_ARCH_HAS_OHCI
 	boolean
@@ -63,6 +55,14 @@ config USB_ARCH_HAS_XHCI
 	boolean
 	default PCI
 
+menuconfig USB_SUPPORT
+	bool "USB support"
+	depends on HAS_IOMEM
+	default y
+	---help---
+	  This option adds core support for Universal Serial Bus (USB).
+	  You will also need drivers from the following menu to make use of it.
+
 if USB_SUPPORT
 
 config USB_COMMON

+ 6 - 5
drivers/usb/core/message.c

@@ -308,7 +308,8 @@ static void sg_complete(struct urb *urb)
 				retval = usb_unlink_urb(io->urbs [i]);
 				if (retval != -EINPROGRESS &&
 				    retval != -ENODEV &&
-				    retval != -EBUSY)
+				    retval != -EBUSY &&
+				    retval != -EIDRM)
 					dev_err(&io->dev->dev,
 						"%s, unlink --> %d\n",
 						__func__, retval);
@@ -317,7 +318,6 @@ static void sg_complete(struct urb *urb)
 		}
 		spin_lock(&io->lock);
 	}
-	urb->dev = NULL;
 
 	/* on the last completion, signal usb_sg_wait() */
 	io->bytes += urb->actual_length;
@@ -524,7 +524,6 @@ void usb_sg_wait(struct usb_sg_request *io)
 		case -ENXIO:	/* hc didn't queue this one */
 		case -EAGAIN:
 		case -ENOMEM:
-			io->urbs[i]->dev = NULL;
 			retval = 0;
 			yield();
 			break;
@@ -542,7 +541,6 @@ void usb_sg_wait(struct usb_sg_request *io)
 
 			/* fail any uncompleted urbs */
 		default:
-			io->urbs[i]->dev = NULL;
 			io->urbs[i]->status = retval;
 			dev_dbg(&io->dev->dev, "%s, submit --> %d\n",
 				__func__, retval);
@@ -593,7 +591,10 @@ void usb_sg_cancel(struct usb_sg_request *io)
 			if (!io->urbs [i]->dev)
 				continue;
 			retval = usb_unlink_urb(io->urbs [i]);
-			if (retval != -EINPROGRESS && retval != -EBUSY)
+			if (retval != -EINPROGRESS
+					&& retval != -ENODEV
+					&& retval != -EBUSY
+					&& retval != -EIDRM)
 				dev_warn(&io->dev->dev, "%s, unlink --> %d\n",
 					__func__, retval);
 		}

+ 12 - 0
drivers/usb/core/urb.c

@@ -539,6 +539,10 @@ EXPORT_SYMBOL_GPL(usb_submit_urb);
  * never submitted, or it was unlinked before, or the hardware is already
  * finished with it), even if the completion handler has not yet run.
  *
+ * The URB must not be deallocated while this routine is running.  In
+ * particular, when a driver calls this routine, it must insure that the
+ * completion handler cannot deallocate the URB.
+ *
  * Unlinking and Endpoint Queues:
  *
  * [The behaviors and guarantees described below do not apply to virtual
@@ -603,6 +607,10 @@ EXPORT_SYMBOL_GPL(usb_unlink_urb);
  * with error -EPERM.  Thus even if the URB's completion handler always
  * tries to resubmit, it will not succeed and the URB will become idle.
  *
+ * The URB must not be deallocated while this routine is running.  In
+ * particular, when a driver calls this routine, it must insure that the
+ * completion handler cannot deallocate the URB.
+ *
  * This routine may not be used in an interrupt context (such as a bottom
  * half or a completion handler), or when holding a spinlock, or in other
  * situations where the caller can't schedule().
@@ -640,6 +648,10 @@ EXPORT_SYMBOL_GPL(usb_kill_urb);
  * with error -EPERM.  Thus even if the URB's completion handler always
  * tries to resubmit, it will not succeed and the URB will become idle.
  *
+ * The URB must not be deallocated while this routine is running.  In
+ * particular, when a driver calls this routine, it must insure that the
+ * completion handler cannot deallocate the URB.
+ *
  * This routine may not be used in an interrupt context (such as a bottom
  * half or a completion handler), or when holding a spinlock, or in other
  * situations where the caller can't schedule().

+ 0 - 1
drivers/usb/gadget/inode.c

@@ -1574,7 +1574,6 @@ static void destroy_ep_files (struct dev_data *dev)
 	DBG (dev, "%s %d\n", __func__, dev->state);
 
 	/* dev->state must prevent interference */
-restart:
 	spin_lock_irq (&dev->lock);
 	while (!list_empty(&dev->epfiles)) {
 		struct ep_data	*ep;

+ 30 - 0
drivers/usb/storage/usb.c

@@ -132,6 +132,35 @@ static struct us_unusual_dev for_dynamic_ids =
 #undef COMPLIANT_DEV
 #undef USUAL_DEV
 
+#ifdef CONFIG_LOCKDEP
+
+static struct lock_class_key us_interface_key[USB_MAXINTERFACES];
+
+static void us_set_lock_class(struct mutex *mutex,
+		struct usb_interface *intf)
+{
+	struct usb_device *udev = interface_to_usbdev(intf);
+	struct usb_host_config *config = udev->actconfig;
+	int i;
+
+	for (i = 0; i < config->desc.bNumInterfaces; i++) {
+		if (config->interface[i] == intf)
+			break;
+	}
+
+	BUG_ON(i == config->desc.bNumInterfaces);
+
+	lockdep_set_class(mutex, &us_interface_key[i]);
+}
+
+#else
+
+static void us_set_lock_class(struct mutex *mutex,
+		struct usb_interface *intf)
+{
+}
+
+#endif
 
 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
 
@@ -895,6 +924,7 @@ int usb_stor_probe1(struct us_data **pus,
 	*pus = us = host_to_us(host);
 	memset(us, 0, sizeof(struct us_data));
 	mutex_init(&(us->dev_mutex));
+	us_set_lock_class(&us->dev_mutex, intf);
 	init_completion(&us->cmnd_ready);
 	init_completion(&(us->notify));
 	init_waitqueue_head(&us->delay_wait);