2008-02-18 20:49:27

by Matthias Kaehlcke

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

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

Signed-off-by: Matthias Kaehlcke <[email protected]>

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

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(Isaac Newton)
.''`.
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2008-02-19 17:29:37

by Daniel Walker

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

On Mon, Feb 18, 2008 at 08:45:35PM +0100, [email protected] 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