diff options
Diffstat (limited to 'bsd-core/drm_lock.c')
| -rw-r--r-- | bsd-core/drm_lock.c | 191 |
1 files changed, 0 insertions, 191 deletions
diff --git a/bsd-core/drm_lock.c b/bsd-core/drm_lock.c deleted file mode 100644 index 24c127a9..00000000 --- a/bsd-core/drm_lock.c +++ /dev/null @@ -1,191 +0,0 @@ -/*- - * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. - * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. - * All Rights Reserved. - * - * Permission is hereby granted, free of charge, to any person obtaining a - * copy of this software and associated documentation files (the "Software"), - * to deal in the Software without restriction, including without limitation - * the rights to use, copy, modify, merge, publish, distribute, sublicense, - * and/or sell copies of the Software, and to permit persons to whom the - * Software is furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice (including the next - * paragraph) shall be included in all copies or substantial portions of the - * Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR - * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, - * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR - * OTHER DEALINGS IN THE SOFTWARE. - * - * Authors: - * Rickard E. (Rik) Faith <faith@valinux.com> - * Gareth Hughes <gareth@valinux.com> - * - */ - -/** @file drm_lock.c - * Implementation of the ioctls and other support code for dealing with the - * hardware lock. - * - * The DRM hardware lock is a shared structure between the kernel and userland. - * - * On uncontended access where the new context was the last context, the - * client may take the lock without dropping down into the kernel, using atomic - * compare-and-set. - * - * If the client finds during compare-and-set that it was not the last owner - * of the lock, it calls the DRM lock ioctl, which may sleep waiting for the - * lock, and may have side-effects of kernel-managed context switching. - * - * When the client releases the lock, if the lock is marked as being contended - * by another client, then the DRM unlock ioctl is called so that the - * contending client may be woken up. - */ - -#include "drmP.h" - -int drm_lock(struct drm_device *dev, void *data, struct drm_file *file_priv) -{ - struct drm_lock *lock = data; - int ret = 0; - - if (lock->context == DRM_KERNEL_CONTEXT) { - DRM_ERROR("Process %d using kernel context %d\n", - DRM_CURRENTPID, lock->context); - return EINVAL; - } - - DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n", - lock->context, DRM_CURRENTPID, dev->lock.hw_lock->lock, - lock->flags); - - if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE) && - lock->context < 0) - return EINVAL; - - DRM_LOCK(); - for (;;) { - if (drm_lock_take(&dev->lock, lock->context)) { - dev->lock.file_priv = file_priv; - dev->lock.lock_time = jiffies; - atomic_inc(&dev->counts[_DRM_STAT_LOCKS]); - break; /* Got lock */ - } - - /* Contention */ - ret = mtx_sleep((void *)&dev->lock.lock_queue, &dev->dev_lock, - PCATCH, "drmlk2", 0); - if (ret != 0) - break; - } - DRM_UNLOCK(); - DRM_DEBUG("%d %s\n", lock->context, ret ? "interrupted" : "has lock"); - - if (ret != 0) - return ret; - - /* XXX: Add signal blocking here */ - - if (dev->driver->dma_quiescent != NULL && - (lock->flags & _DRM_LOCK_QUIESCENT)) - dev->driver->dma_quiescent(dev); - - return 0; -} - -int drm_unlock(struct drm_device *dev, void *data, struct drm_file *file_priv) -{ - struct drm_lock *lock = data; - - DRM_DEBUG("%d (pid %d) requests unlock (0x%08x), flags = 0x%08x\n", - lock->context, DRM_CURRENTPID, dev->lock.hw_lock->lock, - lock->flags); - - if (lock->context == DRM_KERNEL_CONTEXT) { - DRM_ERROR("Process %d using kernel context %d\n", - DRM_CURRENTPID, lock->context); - return EINVAL; - } - - atomic_inc(&dev->counts[_DRM_STAT_UNLOCKS]); - - DRM_LOCK(); - drm_lock_transfer(&dev->lock, DRM_KERNEL_CONTEXT); - - if (drm_lock_free(&dev->lock, DRM_KERNEL_CONTEXT)) { - DRM_ERROR("\n"); - } - DRM_UNLOCK(); - - return 0; -} - -int drm_lock_take(struct drm_lock_data *lock_data, unsigned int context) -{ - volatile unsigned int *lock = &lock_data->hw_lock->lock; - unsigned int old, new; - - do { - old = *lock; - if (old & _DRM_LOCK_HELD) - new = old | _DRM_LOCK_CONT; - else - new = context | _DRM_LOCK_HELD; - } while (!atomic_cmpset_int(lock, old, new)); - - if (_DRM_LOCKING_CONTEXT(old) == context) { - if (old & _DRM_LOCK_HELD) { - if (context != DRM_KERNEL_CONTEXT) { - DRM_ERROR("%d holds heavyweight lock\n", - context); - } - return 0; - } - } - if (new == (context | _DRM_LOCK_HELD)) { - /* Have lock */ - return 1; - } - return 0; -} - -/* 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. */ -int drm_lock_transfer(struct drm_lock_data *lock_data, unsigned int context) -{ - volatile unsigned int *lock = &lock_data->hw_lock->lock; - unsigned int old, new; - - lock_data->file_priv = NULL; - do { - old = *lock; - new = context | _DRM_LOCK_HELD; - } while (!atomic_cmpset_int(lock, old, new)); - - return 1; -} - -int drm_lock_free(struct drm_lock_data *lock_data, unsigned int context) -{ - volatile unsigned int *lock = &lock_data->hw_lock->lock; - unsigned int old, new; - - lock_data->file_priv = NULL; - do { - old = *lock; - new = 0; - } while (!atomic_cmpset_int(lock, old, new)); - - 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)); - return 1; - } - DRM_WAKEUP_INT((void *)&lock_data->lock_queue); - return 0; -} |