[patch 0/3] USB Auerswald ISDN: Convert semaphores to mutexes

[patch 0/3] USB Auerswald ISDN: Convert semaphores to mutexes

[matthias]

USB Auerswald ISDN driver: The semaphores cp->mutex, ccp->readmutex and ccp->mutex are used as mutexes, convert them to the muxex API

-- 
Matthias Kaehlcke
Linux System Developer
Barcelona

              We build too many walls and not enough bridges
                             (Isaac Newton)
                                                                 .''`.
    using free software / Debian GNU/Linux | http://debian.org  : :'  :
                                                                `. `'`
gpg --keyserver pgp.mit.edu --recv-keys 47D8E5D4                  `-

[patch 1/3] Convert stats_sem in a mutex

[matthias]

[-- Attachment #1: usb-misc-auerswald-cp_mutex-to-mutex.diff --]
[-- Type: text/plain, Size: 5368 bytes --]

The semaphore cp->mutex is used as mutex, convert it to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>

Index: linux-2.6/drivers/usb/misc/auerswald.c
===================================================================
--- linux-2.6.orig/drivers/usb/misc/auerswald.c	2008-02-18 19:47:18.000000000 +0100
+++ linux-2.6/drivers/usb/misc/auerswald.c	2008-02-18 19:51:52.000000000 +0100
@@ -31,6 +31,7 @@
 #include <linux/init.h>
 #include <linux/wait.h>
 #include <linux/usb.h>
+#include <linux/mutex.h>
 
 /*-------------------------------------------------------------------*/
 /* Debug support 						     */
@@ -232,7 +233,7 @@
 /* USB device context */
 typedef struct
 {
-	struct semaphore 	mutex;         	    /* protection in user context */
+	struct mutex 	mutex;         	    /* protection in user context */
 	char 			name[20];	    /* name of the /dev/usb entry */
 	unsigned int		dtindex;	    /* index in the device table */
 	struct usb_device *	usbdev;      	    /* USB device handle */
@@ -1376,7 +1377,7 @@
 	if (cp == NULL) {
 		return -ENODEV;
 	}
-	if (down_interruptible (&cp->mutex)) {
+	if (mutex_lock_interruptible(&cp->mutex)) {
 		return -ERESTARTSYS;
 	}
 
@@ -1405,7 +1406,7 @@
 	cp->open_count++;
 	ccp->auerdev = cp;
 	dbg("open %s as /dev/%s", cp->dev_desc, cp->name);
-	up (&cp->mutex);
+	mutex_unlock(&cp->mutex);
 
 	/* file IO stuff */
 	file->f_pos = 0;
@@ -1413,7 +1414,7 @@
 	return nonseekable_open(inode, file);
 
 	/* Error exit */
-ofail:	up (&cp->mutex);
+ofail:	mutex_unlock(&cp->mutex);
 	auerchar_delete (ccp);
 	return ret;
 }
@@ -1440,14 +1441,14 @@
 		up (&ccp->mutex);
                 return -ENODEV;
 	}
-	if (down_interruptible (&cp->mutex)) {
+	if (mutex_lock_interruptible(&cp->mutex)) {
 		up(&ccp->mutex);
 		return -ERESTARTSYS;
 	}
 
 	/* Check for removal */
 	if (!cp->usbdev) {
-		up(&cp->mutex);
+		mutex_unlock(&cp->mutex);
 		up(&ccp->mutex);
                 return -ENODEV;
 	}
@@ -1550,7 +1551,7 @@
 		break;
         }
 	/* release the mutexes */
-	up(&cp->mutex);
+	mutex_unlock(&cp->mutex);
 	up(&ccp->mutex);
 	return ret;
 }
@@ -1721,12 +1722,12 @@
 		up (&ccp->mutex);
 		return -ERESTARTSYS;
 	}
-	if (down_interruptible (&cp->mutex)) {
+	if (mutex_lock_interruptible(&cp->mutex)) {
 		up (&ccp->mutex);
 		return -ERESTARTSYS;
 	}
 	if (!cp->usbdev) {
-		up (&cp->mutex);
+		mutex_unlock(&cp->mutex);
 		up (&ccp->mutex);
 		return -EIO;
 	}
@@ -1750,7 +1751,7 @@
 
 	/* are there any buffers left? */
 	if (!bp) {
-		up (&cp->mutex);
+		mutex_unlock(&cp->mutex);
 		up (&ccp->mutex);
 
 		/* NONBLOCK: don't wait */
@@ -1783,7 +1784,7 @@
 		auerbuf_releasebuf (bp);
 		/* Wake up all processes waiting for a buffer */
 		wake_up (&cp->bufferwait);
-		up (&cp->mutex);
+		mutex_unlock(&cp->mutex);
 		up (&ccp->mutex);
 		return -EFAULT;
 	}
@@ -1803,7 +1804,7 @@
 		    auerchar_ctrlwrite_complete, bp);
 	/* up we go */
 	ret = auerchain_submit_urb (&cp->controlchain, bp->urbp);
-	up (&cp->mutex);
+	mutex_unlock(&cp->mutex);
 	if (ret) {
 		dbg ("auerchar_write: nonzero result of auerchain_submit_urb %d", ret);
 		auerbuf_releasebuf (bp);
@@ -1830,16 +1831,16 @@
 	down(&ccp->mutex);
 	cp = ccp->auerdev;
 	if (cp) {
-		down(&cp->mutex);
+		mutex_lock(&cp->mutex);
 		/* remove an open service */
 		auerswald_removeservice (cp, &ccp->scontext);
 		/* detach from device */
 		if ((--cp->open_count <= 0) && (cp->usbdev == NULL)) {
 			/* usb device waits for removal */
-			up (&cp->mutex);
+			mutex_unlock(&cp->mutex);
 			auerswald_delete (cp);
 		} else {
-			up (&cp->mutex);
+			mutex_unlock(&cp->mutex);
 		}
 		cp = NULL;
 		ccp->auerdev = NULL;
@@ -1917,7 +1918,7 @@
 	}
 
 	/* Initialize device descriptor */
-	init_MUTEX (&cp->mutex);
+	mutex_init(&cp->mutex);
 	cp->usbdev = usbdev;
 	auerchain_init (&cp->controlchain);
         auerbuf_init (&cp->bufctl);
@@ -2042,7 +2043,7 @@
 	/* give back our USB minor number */
 	usb_deregister_dev(intf, &auerswald_class);
 
-	down (&cp->mutex);
+	mutex_lock(&cp->mutex);
 	info ("device /dev/%s now disconnecting", cp->name);
 
 	/* Stop the interrupt endpoint */
@@ -2057,16 +2058,18 @@
 
 	if (cp->open_count == 0) {
 		/* nobody is using this device. So we can clean up now */
-		up (&cp->mutex);/* up() is possible here because no other task
-				   can open the device (see above). I don't want
-				   to kfree() a locked mutex. */
+		mutex_unlock(&cp->mutex);
+		/* mutex_unlock() is possible here because no other task
+		   can open the device (see above). I don't want
+		   to kfree() a locked mutex. */
+
 		auerswald_delete (cp);
 	} else {
 		/* device is used. Remove the pointer to the
 		   usb device (it's not valid any more). The last
 		   release() will do the clean up */
 		cp->usbdev = NULL;
-		up (&cp->mutex);
+		mutex_unlock(&cp->mutex);
 		/* Terminate waiting writers */
 		wake_up (&cp->bufferwait);
 		/* Inform all waiting readers */

-- 
Matthias Kaehlcke
Linux System Developer
Barcelona

              We build too many walls and not enough bridges
                             (Isaac Newton)
                                                                 .''`.
    using free software / Debian GNU/Linux | http://debian.org  : :'  :
                                                                `. `'`
gpg --keyserver pgp.mit.edu --recv-keys 47D8E5D4                  `-

[patch 2/3] Convert ccp->readmutex in a mutex

[matthias]

[-- Attachment #1: usb-misc-auerswald-ccp_readmutex-to-mutex.diff --]
[-- Type: text/plain, Size: 3215 bytes --]

The semaphore ccp->readmutex is used as mutex, convert it to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>

Index: linux-2.6/drivers/usb/misc/auerswald.c
===================================================================
--- linux-2.6.orig/drivers/usb/misc/auerswald.c	2008-02-18 20:12:55.000000000 +0100
+++ linux-2.6/drivers/usb/misc/auerswald.c	2008-02-18 20:10:00.000000000 +0100
@@ -259,7 +259,7 @@
         auerbufctl_t bufctl;            /* controls the buffer chain */
         auerscon_t scontext;            /* service context */
 	wait_queue_head_t readwait;     /* for synchronous reading */
-	struct semaphore readmutex;     /* protection against multiple reads */
+	struct mutex readmutex;		/* protection against multiple reads */
 	pauerbuf_t readbuf;		/* buffer held for partial reading */
 	unsigned int readoffset;	/* current offset in readbuf */
 	unsigned int removed;		/* is != 0 if device is removed */
@@ -1391,7 +1391,7 @@
 
 	/* Initialize device descriptor */
 	init_MUTEX( &ccp->mutex);
-	init_MUTEX( &ccp->readmutex);
+	mutex_init(&ccp->readmutex);
         auerbuf_init (&ccp->bufctl);
         ccp->scontext.id = AUH_UNASSIGNED;
         ccp->scontext.dispatch = auerchar_ctrlread_dispatch;
@@ -1585,7 +1585,7 @@
 	}
 
 	/* only one reader per device allowed */
-	if (down_interruptible (&ccp->readmutex)) {
+	if (mutex_lock_interruptible(&ccp->readmutex)) {
 		up (&ccp->mutex);
 		return -ERESTARTSYS;
 	}
@@ -1603,7 +1603,7 @@
 		if (count) {
 			if (copy_to_user (buf, bp->bufp+ccp->readoffset, count)) {
 				dbg ("auerswald_read: copy_to_user failed");
-				up (&ccp->readmutex);
+				mutex_unlock(&ccp->readmutex);
 				up (&ccp->mutex);
 				return -EFAULT;
 			}
@@ -1618,7 +1618,7 @@
 		}
 		/* return with number of bytes read */
 		if (count) {
-			up (&ccp->readmutex);
+			mutex_unlock(&ccp->readmutex);
 			up (&ccp->mutex);
 			return count;
 		}
@@ -1655,7 +1655,7 @@
                 dbg ("No read buffer available, returning -EAGAIN");
 		set_current_state (TASK_RUNNING);
 		remove_wait_queue (&ccp->readwait, &wait);
-		up (&ccp->readmutex);
+		mutex_unlock(&ccp->readmutex);
 		up (&ccp->mutex);
 		return -EAGAIN;  /* nonblocking, no data available */
         }
@@ -1666,18 +1666,18 @@
 	remove_wait_queue (&ccp->readwait, &wait);
 	if (signal_pending (current)) {
 		/* waked up by a signal */
-		up (&ccp->readmutex);
+		mutex_unlock(&ccp->readmutex);
 		return -ERESTARTSYS;
 	}
 
 	/* Anything left to read? */
 	if ((ccp->scontext.id == AUH_UNASSIGNED) || ccp->removed) {
-		up (&ccp->readmutex);
+		mutex_unlock(&ccp->readmutex);
 		return -EIO;
 	}
 
 	if (down_interruptible (&ccp->mutex)) {
-		up (&ccp->readmutex);
+		mutex_unlock(&ccp->readmutex);
 		return -ERESTARTSYS;
 	}
 

-- 
Matthias Kaehlcke
Linux System Developer
Barcelona

              We build too many walls and not enough bridges
                             (Isaac Newton)
                                                                 .''`.
    using free software / Debian GNU/Linux | http://debian.org  : :'  :
                                                                `. `'`
gpg --keyserver pgp.mit.edu --recv-keys 47D8E5D4                  `-

[patch 3/3] Convert ccp->mutex in a mutex

[matthias]

[-- Attachment #1: usb-misc-auerswald-ccp_mutex-to-mutex.diff --]
[-- Type: text/plain, Size: 5741 bytes --]

The semaphore ccp->mutex is used as mutex, convert it to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>

Index: linux-2.6/drivers/usb/misc/auerswald.c
===================================================================
--- linux-2.6.orig/drivers/usb/misc/auerswald.c	2008-02-18 20:17:08.000000000 +0100
+++ linux-2.6/drivers/usb/misc/auerswald.c	2008-02-18 20:28:02.000000000 +0100
@@ -254,7 +254,7 @@
 /* character device context */
 typedef struct
 {
-	struct semaphore mutex;         /* protection in user context */
+	struct mutex mutex;		/* protection in user context */
 	pauerswald_t auerdev;           /* context pointer of assigned device */
         auerbufctl_t bufctl;            /* controls the buffer chain */
         auerscon_t scontext;            /* service context */
@@ -1390,7 +1390,7 @@
 	}
 
 	/* Initialize device descriptor */
-	init_MUTEX( &ccp->mutex);
+	mutex_init(&ccp->mutex);
 	mutex_init(&ccp->readmutex);
         auerbuf_init (&ccp->bufctl);
         ccp->scontext.id = AUH_UNASSIGNED;
@@ -1433,23 +1433,23 @@
         dbg ("ioctl");
 
 	/* get the mutexes */
-	if (down_interruptible (&ccp->mutex)) {
+	if (mutex_lock_interruptible(&ccp->mutex)) {
 		return -ERESTARTSYS;
 	}
 	cp = ccp->auerdev;
 	if (!cp) {
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
                 return -ENODEV;
 	}
 	if (mutex_lock_interruptible(&cp->mutex)) {
-		up(&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return -ERESTARTSYS;
 	}
 
 	/* Check for removal */
 	if (!cp->usbdev) {
 		mutex_unlock(&cp->mutex);
-		up(&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
                 return -ENODEV;
 	}
 
@@ -1552,7 +1552,7 @@
         }
 	/* release the mutexes */
 	mutex_unlock(&cp->mutex);
-	up(&ccp->mutex);
+	mutex_unlock(&ccp->mutex);
 	return ret;
 }
 
@@ -1575,18 +1575,18 @@
 		return 0;
 
 	/* get the mutex */
-	if (down_interruptible (&ccp->mutex))
+	if (mutex_lock_interruptible(&ccp->mutex))
 		return -ERESTARTSYS;
 
 	/* Can we expect to read something? */
 	if (ccp->scontext.id == AUH_UNASSIGNED) {
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
                 return -EIO;
 	}
 
 	/* only one reader per device allowed */
 	if (mutex_lock_interruptible(&ccp->readmutex)) {
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return -ERESTARTSYS;
 	}
 
@@ -1604,7 +1604,7 @@
 			if (copy_to_user (buf, bp->bufp+ccp->readoffset, count)) {
 				dbg ("auerswald_read: copy_to_user failed");
 				mutex_unlock(&ccp->readmutex);
-				up (&ccp->mutex);
+				mutex_unlock(&ccp->mutex);
 				return -EFAULT;
 			}
 		}
@@ -1619,7 +1619,7 @@
 		/* return with number of bytes read */
 		if (count) {
 			mutex_unlock(&ccp->readmutex);
-			up (&ccp->mutex);
+			mutex_unlock(&ccp->mutex);
 			return count;
 		}
 	}
@@ -1656,12 +1656,12 @@
 		set_current_state (TASK_RUNNING);
 		remove_wait_queue (&ccp->readwait, &wait);
 		mutex_unlock(&ccp->readmutex);
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return -EAGAIN;  /* nonblocking, no data available */
         }
 
 	/* yes, we should wait! */
-	up (&ccp->mutex); /* allow other operations while we wait */
+	mutex_unlock(&ccp->mutex); /* allow other operations while we wait */
 	schedule();
 	remove_wait_queue (&ccp->readwait, &wait);
 	if (signal_pending (current)) {
@@ -1676,7 +1676,7 @@
 		return -EIO;
 	}
 
-	if (down_interruptible (&ccp->mutex)) {
+	if (mutex_lock_interruptible(&ccp->mutex)) {
 		mutex_unlock(&ccp->readmutex);
 		return -ERESTARTSYS;
 	}
@@ -1708,27 +1708,27 @@
 
 write_again:
 	/* get the mutex */
-	if (down_interruptible (&ccp->mutex))
+	if (mutex_lock_interruptible(&ccp->mutex))
 		return -ERESTARTSYS;
 
 	/* Can we expect to write something? */
 	if (ccp->scontext.id == AUH_UNASSIGNED) {
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
                 return -EIO;
 	}
 
 	cp = ccp->auerdev;
 	if (!cp) {
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return -ERESTARTSYS;
 	}
 	if (mutex_lock_interruptible(&cp->mutex)) {
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return -ERESTARTSYS;
 	}
 	if (!cp->usbdev) {
 		mutex_unlock(&cp->mutex);
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return -EIO;
 	}
 	/* Prepare for sleep */
@@ -1752,7 +1752,7 @@
 	/* are there any buffers left? */
 	if (!bp) {
 		mutex_unlock(&cp->mutex);
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 
 		/* NONBLOCK: don't wait */
 		if (file->f_flags & O_NONBLOCK) {
@@ -1785,7 +1785,7 @@
 		/* Wake up all processes waiting for a buffer */
 		wake_up (&cp->bufferwait);
 		mutex_unlock(&cp->mutex);
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return -EFAULT;
 	}
 
@@ -1810,12 +1810,12 @@
 		auerbuf_releasebuf (bp);
 		/* Wake up all processes waiting for a buffer */
 		wake_up (&cp->bufferwait);
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return -EIO;
 	}
 	else {
 		dbg ("auerchar_write: Write OK");
-		up (&ccp->mutex);
+		mutex_unlock(&ccp->mutex);
 		return len;
 	}
 }
@@ -1828,7 +1828,7 @@
 	pauerswald_t cp;
 	dbg("release");
 
-	down(&ccp->mutex);
+	mutex_lock(&ccp->mutex);
 	cp = ccp->auerdev;
 	if (cp) {
 		mutex_lock(&cp->mutex);
@@ -1845,7 +1845,7 @@
 		cp = NULL;
 		ccp->auerdev = NULL;
 	}
-	up (&ccp->mutex);
+	mutex_unlock(&ccp->mutex);
 	auerchar_delete (ccp);
 
 	return 0;

-- 
Matthias Kaehlcke
Linux System Developer
Barcelona

              We build too many walls and not enough bridges
                             (Isaac Newton)
                                                                 .''`.
    using free software / Debian GNU/Linux | http://debian.org  : :'  :
                                                                `. `'`
gpg --keyserver pgp.mit.edu --recv-keys 47D8E5D4                  `-

Re: [patch 2/3] Convert ccp->readmutex in a mutex

[Daniel Walker]

On Mon, Feb 18, 2008 at 08:45:35PM +0100, matthias@kaehlcke.net wrote:
> @@ -1391,7 +1391,7 @@
>  
>  	/* Initialize device descriptor */
>  	init_MUTEX( &ccp->mutex);
> -	init_MUTEX( &ccp->readmutex);
> +	mutex_init(&ccp->readmutex);
>          auerbuf_init (&ccp->bufctl);
>          ccp->scontext.id = AUH_UNASSIGNED;
>          ccp->scontext.dispatch = auerchar_ctrlread_dispatch;

Whitespace problems here? Might be good to do a checkpatch cleanup on this one too ..

Daniel