[PATCH] USB: convert a bunch of USB semaphores to mutexes

the patch below converts a bunch of semaphores-used-as-mutex in the USB
code to mutexes

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/mon/mon_main.c

@@ -12,6 +12,7 @@
 #include <linux/debugfs.h>
 #include <linux/smp_lock.h>
 #include <linux/notifier.h>
+#include <linux/mutex.h>
 
 #include "usb_mon.h"
 #include "../core/hcd.h"
@@ -23,7 +24,7 @@ static void mon_dissolve(struct mon_bus *mbus, struct usb_bus *ubus);
 static void mon_bus_drop(struct kref *r);
 static void mon_bus_init(struct dentry *mondir, struct usb_bus *ubus);
 
-DECLARE_MUTEX(mon_lock);
+DEFINE_MUTEX(mon_lock);
 
 static struct dentry *mon_dir;		/* /dbg/usbmon */
 static LIST_HEAD(mon_buses);		/* All buses we know: struct mon_bus */
@@ -196,14 +197,14 @@ static void mon_bus_remove(struct usb_bus *ubus)
 {
 	struct mon_bus *mbus = ubus->mon_bus;
 
-	down(&mon_lock);
+	mutex_lock(&mon_lock);
 	list_del(&mbus->bus_link);
 	debugfs_remove(mbus->dent_t);
 	debugfs_remove(mbus->dent_s);
 
 	mon_dissolve(mbus, ubus);
 	kref_put(&mbus->ref, mon_bus_drop);
-	up(&mon_lock);
+	mutex_unlock(&mon_lock);
 }
 
 static int mon_notify(struct notifier_block *self, unsigned long action,
@@ -307,9 +308,9 @@ static void mon_bus_init(struct dentry *mondir, struct usb_bus *ubus)
 		goto err_create_s;
 	mbus->dent_s = d;
 
-	down(&mon_lock);
+	mutex_lock(&mon_lock);
 	list_add_tail(&mbus->bus_link, &mon_buses);
-	up(&mon_lock);
+	mutex_unlock(&mon_lock);
 	return;
 
 err_create_s:
@@ -347,11 +348,11 @@ static int __init mon_init(void)
 
 	usb_register_notify(&mon_nb);
 
-	down(&usb_bus_list_lock);
+	mutex_lock(&usb_bus_list_lock);
 	list_for_each_entry (ubus, &usb_bus_list, bus_list) {
 		mon_bus_init(mondir, ubus);
 	}
-	up(&usb_bus_list_lock);
+	mutex_unlock(&usb_bus_list_lock);
 	return 0;
 }
 
@@ -363,7 +364,7 @@ static void __exit mon_exit(void)
 	usb_unregister_notify(&mon_nb);
 	usb_mon_deregister();
 
-	down(&mon_lock);
+	mutex_lock(&mon_lock);
 	while (!list_empty(&mon_buses)) {
 		p = mon_buses.next;
 		mbus = list_entry(p, struct mon_bus, bus_link);
@@ -387,7 +388,7 @@ static void __exit mon_exit(void)
 		mon_dissolve(mbus, mbus->u_bus);
 		kref_put(&mbus->ref, mon_bus_drop);
 	}
-	up(&mon_lock);
+	mutex_unlock(&mon_lock);
 
 	debugfs_remove(mon_dir);
 }

drivers/usb/mon/mon_text.c

@@ -8,6 +8,7 @@
 #include <linux/list.h>
 #include <linux/usb.h>
 #include <linux/time.h>
+#include <linux/mutex.h>
 #include <asm/uaccess.h>
 
 #include "usb_mon.h"
@@ -54,7 +55,7 @@ struct mon_reader_text {
 	wait_queue_head_t wait;
 	int printf_size;
 	char *printf_buf;
-	struct semaphore printf_lock;
+	struct mutex printf_lock;
 
 	char slab_name[SLAB_NAME_SZ];
 };
@@ -208,7 +209,7 @@ static int mon_text_open(struct inode *inode, struct file *file)
 	struct mon_reader_text *rp;
 	int rc;
 
-	down(&mon_lock);
+	mutex_lock(&mon_lock);
 	mbus = inode->u.generic_ip;
 	ubus = mbus->u_bus;
 
@@ -220,7 +221,7 @@ static int mon_text_open(struct inode *inode, struct file *file)
 	memset(rp, 0, sizeof(struct mon_reader_text));
 	INIT_LIST_HEAD(&rp->e_list);
 	init_waitqueue_head(&rp->wait);
-	init_MUTEX(&rp->printf_lock);
+	mutex_init(&rp->printf_lock);
 
 	rp->printf_size = PRINTF_DFL;
 	rp->printf_buf = kmalloc(rp->printf_size, GFP_KERNEL);
@@ -247,7 +248,7 @@ static int mon_text_open(struct inode *inode, struct file *file)
 	mon_reader_add(mbus, &rp->r);
 
 	file->private_data = rp;
-	up(&mon_lock);
+	mutex_unlock(&mon_lock);
 	return 0;
 
 // err_busy:
@@ -257,7 +258,7 @@ err_slab:
 err_alloc_pr:
 	kfree(rp);
 err_alloc:
-	up(&mon_lock);
+	mutex_unlock(&mon_lock);
 	return rc;
 }
 
@@ -301,7 +302,7 @@ static ssize_t mon_text_read(struct file *file, char __user *buf,
 	set_current_state(TASK_RUNNING);
 	remove_wait_queue(&rp->wait, &waita);
 
-	down(&rp->printf_lock);
+	mutex_lock(&rp->printf_lock);
 	cnt = 0;
 	pbuf = rp->printf_buf;
 	limit = rp->printf_size;
@@ -358,7 +359,7 @@ static ssize_t mon_text_read(struct file *file, char __user *buf,
 
 	if (copy_to_user(buf, rp->printf_buf, cnt))
 		cnt = -EFAULT;
-	up(&rp->printf_lock);
+	mutex_unlock(&rp->printf_lock);
 	kmem_cache_free(rp->e_slab, ep);
 	return cnt;
 }
@@ -371,12 +372,12 @@ static int mon_text_release(struct inode *inode, struct file *file)
 	struct list_head *p;
 	struct mon_event_text *ep;
 
-	down(&mon_lock);
+	mutex_lock(&mon_lock);
 	mbus = inode->u.generic_ip;
 
 	if (mbus->nreaders <= 0) {
 		printk(KERN_ERR TAG ": consistency error on close\n");
-		up(&mon_lock);
+		mutex_unlock(&mon_lock);
 		return 0;
 	}
 	mon_reader_del(mbus, &rp->r);
@@ -402,7 +403,7 @@ static int mon_text_release(struct inode *inode, struct file *file)
 	kfree(rp->printf_buf);
 	kfree(rp);
 
-	up(&mon_lock);
+	mutex_unlock(&mon_lock);
 	return 0;
 }
 

drivers/usb/mon/usb_mon.h

@@ -49,7 +49,7 @@ void mon_reader_del(struct mon_bus *mbus, struct mon_reader *r);
  */
 extern char mon_dmapeek(unsigned char *dst, dma_addr_t dma_addr, int len);
 
-extern struct semaphore mon_lock;
+extern struct mutex mon_lock;
 
 extern struct file_operations mon_fops_text;
 extern struct file_operations mon_fops_stat;