X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fusb%2Fcore%2Ffile.c;h=5d860bc9b42143f6729a9df40521ec42943b21b1;hb=7071a3ce0ca058ad2a9e3e8c33f30fb0bce62005;hp=01c857ac27afc09eed98c1a190d794073b73c470;hpb=64106104dd2d4a6280777e88c1cbf9f7a52c30bd;p=linux-2.6-omap-h63xx.git

diff --git a/drivers/usb/core/file.c b/drivers/usb/core/file.c
index 01c857ac27a..913fb866789 100644
--- a/drivers/usb/core/file.c
+++ b/drivers/usb/core/file.c
@@ -16,15 +16,16 @@
  */
 
 #include <linux/module.h>
-#include <linux/spinlock.h>
 #include <linux/errno.h>
+#include <linux/rwsem.h>
+#include <linux/smp_lock.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 +34,12 @@ 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);
+	lock_kernel();
+	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 +51,9 @@ 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);
+	unlock_kernel();
 	return err;
 }
 
@@ -148,7 +150,7 @@ int usb_register_dev(struct usb_interface *intf,
 	int retval = -EINVAL;
 	int minor_base = class_driver->minor_base;
 	int minor = 0;
-	char name[BUS_ID_SIZE];
+	char name[20];
 	char *temp;
 
 #ifdef CONFIG_USB_DYNAMIC_MINORS
@@ -166,7 +168,7 @@ 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 +178,7 @@ int usb_register_dev(struct usb_interface *intf,
 		retval = 0;
 		break;
 	}
-	spin_unlock (&minor_lock);
+	up_write(&minor_rwsem);
 
 	if (retval)
 		goto exit;
@@ -188,24 +190,24 @@ int usb_register_dev(struct usb_interface *intf,
 	intf->minor = minor;
 
 	/* create a usb class device for this usb interface */
-	snprintf(name, BUS_ID_SIZE, class_driver->name, minor - minor_base);
+	snprintf(name, sizeof(name), class_driver->name, minor - minor_base);
 	temp = strrchr(name, '/');
-	if (temp && (temp[1] != 0x00))
+	if (temp && (temp[1] != '\0'))
 		++temp;
 	else
 		temp = name;
 	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:
 	return retval;
 }
-EXPORT_SYMBOL(usb_register_dev);
+EXPORT_SYMBOL_GPL(usb_register_dev);
 
 /**
  * usb_deregister_dev - deregister a USB device's dynamic minor.
@@ -225,7 +227,7 @@ void usb_deregister_dev(struct usb_interface *intf,
 			struct usb_class_driver *class_driver)
 {
 	int minor_base = class_driver->minor_base;
-	char name[BUS_ID_SIZE];
+	char name[20];
 
 #ifdef CONFIG_USB_DYNAMIC_MINORS
 	minor_base = 0;
@@ -236,16 +238,14 @@ 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);
+	snprintf(name, sizeof(name), class_driver->name, intf->minor - minor_base);
 	device_destroy(usb_class->class, MKDEV(USB_MAJOR, intf->minor));
 	intf->usb_dev = NULL;
 	intf->minor = -1;
 	destroy_usb_class();
 }
-EXPORT_SYMBOL(usb_deregister_dev);
-
-
+EXPORT_SYMBOL_GPL(usb_deregister_dev);