diff options
Diffstat (limited to 'drivers/char/drm/drm_lock.c')
-rw-r--r-- | drivers/char/drm/drm_lock.c | 187 |
1 files changed, 96 insertions, 91 deletions
diff --git a/drivers/char/drm/drm_lock.c b/drivers/char/drm/drm_lock.c index 4702d863bcc..b48a595d54e 100644 --- a/drivers/char/drm/drm_lock.c +++ b/drivers/char/drm/drm_lock.c @@ -1,7 +1,7 @@ /** - * \file drm_lock.h + * \file drm_lock.c * IOCTLs for locking - * + * * \author Rickard E. (Rik) Faith <faith@valinux.com> * \author Gareth Hughes <gareth@valinux.com> */ @@ -35,12 +35,12 @@ #include "drmP.h" -static int drm_lock_transfer(drm_device_t *dev, +static int drm_lock_transfer(drm_device_t * dev, __volatile__ unsigned int *lock, unsigned int context); static int drm_notifier(void *priv); -/** +/** * Lock ioctl. * * \param inode device inode. @@ -51,91 +51,95 @@ static int drm_notifier(void *priv); * * Add the current task to the lock wait queue, and attempt to take to lock. */ -int drm_lock( struct inode *inode, struct file *filp, - unsigned int cmd, unsigned long arg ) +int drm_lock(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) { - drm_file_t *priv = filp->private_data; - drm_device_t *dev = priv->head->dev; - DECLARE_WAITQUEUE( entry, current ); - drm_lock_t lock; - int ret = 0; + drm_file_t *priv = filp->private_data; + drm_device_t *dev = priv->head->dev; + DECLARE_WAITQUEUE(entry, current); + drm_lock_t lock; + int ret = 0; ++priv->lock_count; - if ( copy_from_user( &lock, (drm_lock_t __user *)arg, sizeof(lock) ) ) + if (copy_from_user(&lock, (drm_lock_t __user *) arg, sizeof(lock))) return -EFAULT; - if ( lock.context == DRM_KERNEL_CONTEXT ) { - DRM_ERROR( "Process %d using kernel context %d\n", - current->pid, lock.context ); - return -EINVAL; - } + if (lock.context == DRM_KERNEL_CONTEXT) { + DRM_ERROR("Process %d using kernel context %d\n", + current->pid, lock.context); + return -EINVAL; + } - DRM_DEBUG( "%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n", - lock.context, current->pid, - dev->lock.hw_lock->lock, lock.flags ); + DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n", + lock.context, current->pid, + dev->lock.hw_lock->lock, lock.flags); if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE)) - if ( lock.context < 0 ) + if (lock.context < 0) return -EINVAL; - add_wait_queue( &dev->lock.lock_queue, &entry ); + add_wait_queue(&dev->lock.lock_queue, &entry); for (;;) { __set_current_state(TASK_INTERRUPTIBLE); - if ( !dev->lock.hw_lock ) { + if (!dev->lock.hw_lock) { /* Device has been unregistered */ ret = -EINTR; break; } - if ( drm_lock_take( &dev->lock.hw_lock->lock, - lock.context ) ) { - dev->lock.filp = filp; + if (drm_lock_take(&dev->lock.hw_lock->lock, lock.context)) { + dev->lock.filp = filp; dev->lock.lock_time = jiffies; - atomic_inc( &dev->counts[_DRM_STAT_LOCKS] ); - break; /* Got lock */ + atomic_inc(&dev->counts[_DRM_STAT_LOCKS]); + break; /* Got lock */ } - + /* Contention */ schedule(); - if ( signal_pending( current ) ) { + if (signal_pending(current)) { ret = -ERESTARTSYS; break; } } __set_current_state(TASK_RUNNING); - remove_wait_queue( &dev->lock.lock_queue, &entry ); + remove_wait_queue(&dev->lock.lock_queue, &entry); + + DRM_DEBUG("%d %s\n", lock.context, ret ? "interrupted" : "has lock"); + if (ret) + return ret; - sigemptyset( &dev->sigmask ); - sigaddset( &dev->sigmask, SIGSTOP ); - sigaddset( &dev->sigmask, SIGTSTP ); - sigaddset( &dev->sigmask, SIGTTIN ); - sigaddset( &dev->sigmask, SIGTTOU ); + sigemptyset(&dev->sigmask); + sigaddset(&dev->sigmask, SIGSTOP); + sigaddset(&dev->sigmask, SIGTSTP); + sigaddset(&dev->sigmask, SIGTTIN); + sigaddset(&dev->sigmask, SIGTTOU); dev->sigdata.context = lock.context; - dev->sigdata.lock = dev->lock.hw_lock; - block_all_signals( drm_notifier, - &dev->sigdata, &dev->sigmask ); - + dev->sigdata.lock = dev->lock.hw_lock; + block_all_signals(drm_notifier, &dev->sigdata, &dev->sigmask); + if (dev->driver->dma_ready && (lock.flags & _DRM_LOCK_READY)) dev->driver->dma_ready(dev); - - if ( dev->driver->dma_quiescent && (lock.flags & _DRM_LOCK_QUIESCENT )) - return dev->driver->dma_quiescent(dev); - - /* dev->driver->kernel_context_switch isn't used by any of the x86 + + if (dev->driver->dma_quiescent && (lock.flags & _DRM_LOCK_QUIESCENT)) { + if (dev->driver->dma_quiescent(dev)) { + DRM_DEBUG("%d waiting for DMA quiescent\n", lock.context); + return DRM_ERR(EBUSY); + } + } + + /* dev->driver->kernel_context_switch isn't used by any of the x86 * drivers but is used by the Sparc driver. */ - - if (dev->driver->kernel_context_switch && + + if (dev->driver->kernel_context_switch && dev->last_context != lock.context) { - dev->driver->kernel_context_switch(dev, dev->last_context, - lock.context); + dev->driver->kernel_context_switch(dev, dev->last_context, + lock.context); } - DRM_DEBUG( "%d %s\n", lock.context, ret ? "interrupted" : "has lock" ); - - return ret; + return 0; } -/** +/** * Unlock ioctl. * * \param inode device inode. @@ -146,23 +150,23 @@ int drm_lock( struct inode *inode, struct file *filp, * * Transfer and free the lock. */ -int drm_unlock( struct inode *inode, struct file *filp, - unsigned int cmd, unsigned long arg ) +int drm_unlock(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) { drm_file_t *priv = filp->private_data; drm_device_t *dev = priv->head->dev; drm_lock_t lock; - if ( copy_from_user( &lock, (drm_lock_t __user *)arg, sizeof(lock) ) ) + if (copy_from_user(&lock, (drm_lock_t __user *) arg, sizeof(lock))) return -EFAULT; - if ( lock.context == DRM_KERNEL_CONTEXT ) { - DRM_ERROR( "Process %d using kernel context %d\n", - current->pid, lock.context ); + if (lock.context == DRM_KERNEL_CONTEXT) { + DRM_ERROR("Process %d using kernel context %d\n", + current->pid, lock.context); return -EINVAL; } - atomic_inc( &dev->counts[_DRM_STAT_UNLOCKS] ); + atomic_inc(&dev->counts[_DRM_STAT_UNLOCKS]); /* kernel_context_switch isn't used by any of the x86 drm * modules but is required by the Sparc driver. @@ -170,12 +174,12 @@ int drm_unlock( struct inode *inode, struct file *filp, if (dev->driver->kernel_context_switch_unlock) dev->driver->kernel_context_switch_unlock(dev, &lock); else { - drm_lock_transfer( dev, &dev->lock.hw_lock->lock, - DRM_KERNEL_CONTEXT ); - - if ( drm_lock_free( dev, &dev->lock.hw_lock->lock, - DRM_KERNEL_CONTEXT ) ) { - DRM_ERROR( "\n" ); + drm_lock_transfer(dev, &dev->lock.hw_lock->lock, + DRM_KERNEL_CONTEXT); + + if (drm_lock_free(dev, &dev->lock.hw_lock->lock, + DRM_KERNEL_CONTEXT)) { + DRM_ERROR("\n"); } } @@ -198,8 +202,10 @@ int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context) do { old = *lock; - if (old & _DRM_LOCK_HELD) new = old | _DRM_LOCK_CONT; - else new = context | _DRM_LOCK_HELD; + if (old & _DRM_LOCK_HELD) + new = old | _DRM_LOCK_CONT; + else + new = context | _DRM_LOCK_HELD; prev = cmpxchg(lock, old, new); } while (prev != old); if (_DRM_LOCKING_CONTEXT(old) == context) { @@ -212,7 +218,7 @@ int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context) } } if (new == (context | _DRM_LOCK_HELD)) { - /* Have lock */ + /* Have lock */ return 1; } return 0; @@ -220,8 +226,8 @@ int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context) /** * This takes a lock forcibly and hands it to context. Should ONLY be used - * inside *_unlock to give lock to kernel before calling *_dma_schedule. - * + * inside *_unlock to give lock to kernel before calling *_dma_schedule. + * * \param dev DRM device. * \param lock lock pointer. * \param context locking context. @@ -230,7 +236,7 @@ int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context) * Resets the lock file pointer. * Marks the lock as held by the given context, via the \p cmpxchg instruction. */ -static int drm_lock_transfer(drm_device_t *dev, +static int drm_lock_transfer(drm_device_t * dev, __volatile__ unsigned int *lock, unsigned int context) { @@ -238,8 +244,8 @@ static int drm_lock_transfer(drm_device_t *dev, dev->lock.filp = NULL; do { - old = *lock; - new = context | _DRM_LOCK_HELD; + old = *lock; + new = context | _DRM_LOCK_HELD; prev = cmpxchg(lock, old, new); } while (prev != old); return 1; @@ -247,30 +253,29 @@ static int drm_lock_transfer(drm_device_t *dev, /** * Free lock. - * + * * \param dev DRM device. * \param lock lock. * \param context context. - * + * * Resets the lock file pointer. * Marks the lock as not held, via the \p cmpxchg instruction. Wakes any task * waiting on the lock queue. */ -int drm_lock_free(drm_device_t *dev, - __volatile__ unsigned int *lock, unsigned int context) +int drm_lock_free(drm_device_t * dev, + __volatile__ unsigned int *lock, unsigned int context) { unsigned int old, new, prev; dev->lock.filp = NULL; do { - old = *lock; - new = 0; + old = *lock; + new = 0; prev = cmpxchg(lock, old, new); } while (prev != old); if (_DRM_LOCK_IS_HELD(old) && _DRM_LOCKING_CONTEXT(old) != context) { DRM_ERROR("%d freed heavyweight lock held by %d\n", - context, - _DRM_LOCKING_CONTEXT(old)); + context, _DRM_LOCKING_CONTEXT(old)); return 1; } wake_up_interruptible(&dev->lock.lock_queue); @@ -290,19 +295,19 @@ int drm_lock_free(drm_device_t *dev, */ static int drm_notifier(void *priv) { - drm_sigdata_t *s = (drm_sigdata_t *)priv; - unsigned int old, new, prev; - + drm_sigdata_t *s = (drm_sigdata_t *) priv; + unsigned int old, new, prev; - /* Allow signal delivery if lock isn't held */ + /* Allow signal delivery if lock isn't held */ if (!s->lock || !_DRM_LOCK_IS_HELD(s->lock->lock) - || _DRM_LOCKING_CONTEXT(s->lock->lock) != s->context) return 1; + || _DRM_LOCKING_CONTEXT(s->lock->lock) != s->context) + return 1; - /* Otherwise, set flag to force call to - drmUnlock */ + /* Otherwise, set flag to force call to + drmUnlock */ do { - old = s->lock->lock; - new = old | _DRM_LOCK_CONT; + old = s->lock->lock; + new = old | _DRM_LOCK_CONT; prev = cmpxchg(&s->lock->lock, old, new); } while (prev != old); return 0; |