Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6: (149 commits)
  USB: ohci-pnx4008: Remove unnecessary cast of return value of kzalloc
  USB: additions to the quirk list
  usb-storage: implement autosuspend
  USB: cdc-acm: add new device id to option driver
  USB: goku_udc trivial cleanups
  USB: usb gadget stack can now -DDEBUG with Kconfig
  usb gadget stack: remove usb_ep_*_buffer(), part 2
  usb gadget stack: remove usb_ep_*_buffer(), part 1
  USB: pxa2xx_udc -- cleanups, mostly removing dma hooks
  USB: pxa2xx_udc: use generic gpio layer
  USB: quirk for samsung printer
  USB: usb/dma doc updates
  USB: drivers/usb/storage/unusual_devs.h whitespace cleanup
  USB: remove Makefile reference to obsolete OHCI_AT91
  USB: io_*: remove bogus termios no change checks
  USB: mos7720: remove bogus no termios change check
  USB: visor and whiteheat: remove bogus termios change checks
  USB: pl2303: remove bogus checks and fix speed support to use tty_get_baud_rate()
  USB: mos7840.c: turn this into a serial driver
  USB: make the usb_device numa_node get assigned from controller
  ...

1 files changed, 13 insertions, 16 deletions

diff --git a/drivers/usb/core/file.c b/drivers/usb/core/file.c
index 01c857ac27a..5d860bc9b42 100644
--- a/drivers/usb/core/file.c
+++ b/drivers/usb/core/file.c
@@ -16,15 +16,15 @@
  */
 
 #include <linux/module.h>
-#include <linux/spinlock.h>
 #include <linux/errno.h>
+#include <linux/rwsem.h>
 #include <linux/usb.h>
 
 #include "usb.h"
 
 #define MAX_USB_MINORS	256
 static const struct file_operations *usb_minors[MAX_USB_MINORS];
-static DEFINE_SPINLOCK(minor_lock);
+static DECLARE_RWSEM(minor_rwsem);
 
 static int usb_open(struct inode * inode, struct file * file)
 {
@@ -33,14 +33,11 @@ static int usb_open(struct inode * inode, struct file * file)
 	int err = -ENODEV;
 	const struct file_operations *old_fops, *new_fops = NULL;
 
-	spin_lock (&minor_lock);
+	down_read(&minor_rwsem);
 	c = usb_minors[minor];
 
-	if (!c || !(new_fops = fops_get(c))) {
-		spin_unlock(&minor_lock);
-		return err;
-	}
-	spin_unlock(&minor_lock);
+	if (!c || !(new_fops = fops_get(c)))
+		goto done;
 
 	old_fops = file->f_op;
 	file->f_op = new_fops;
@@ -52,6 +49,8 @@ static int usb_open(struct inode * inode, struct file * file)
 		file->f_op = fops_get(old_fops);
 	}
 	fops_put(old_fops);
+ done:
+	up_read(&minor_rwsem);
 	return err;
 }
 
@@ -166,7 +165,7 @@ int usb_register_dev(struct usb_interface *intf,
 	if (class_driver->fops == NULL)
 		goto exit;
 
-	spin_lock (&minor_lock);
+	down_write(&minor_rwsem);
 	for (minor = minor_base; minor < MAX_USB_MINORS; ++minor) {
 		if (usb_minors[minor])
 			continue;
@@ -176,7 +175,7 @@ int usb_register_dev(struct usb_interface *intf,
 		retval = 0;
 		break;
 	}
-	spin_unlock (&minor_lock);
+	up_write(&minor_rwsem);
 
 	if (retval)
 		goto exit;
@@ -197,9 +196,9 @@ int usb_register_dev(struct usb_interface *intf,
 	intf->usb_dev = device_create(usb_class->class, &intf->dev,
 				      MKDEV(USB_MAJOR, minor), "%s", temp);
 	if (IS_ERR(intf->usb_dev)) {
-		spin_lock (&minor_lock);
+		down_write(&minor_rwsem);
 		usb_minors[intf->minor] = NULL;
-		spin_unlock (&minor_lock);
+		up_write(&minor_rwsem);
 		retval = PTR_ERR(intf->usb_dev);
 	}
 exit:
@@ -236,9 +235,9 @@ void usb_deregister_dev(struct usb_interface *intf,
 
 	dbg ("removing %d minor", intf->minor);
 
-	spin_lock (&minor_lock);
+	down_write(&minor_rwsem);
 	usb_minors[intf->minor] = NULL;
-	spin_unlock (&minor_lock);
+	up_write(&minor_rwsem);
 
 	snprintf(name, BUS_ID_SIZE, class_driver->name, intf->minor - minor_base);
 	device_destroy(usb_class->class, MKDEV(USB_MAJOR, intf->minor));
@@ -247,5 +246,3 @@ void usb_deregister_dev(struct usb_interface *intf,
 	destroy_usb_class();
 }
 EXPORT_SYMBOL(usb_deregister_dev);
-
-