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Diffstat (limited to 'linux-core/drm_bo_lock.c')
-rw-r--r--linux-core/drm_bo_lock.c189
1 files changed, 0 insertions, 189 deletions
diff --git a/linux-core/drm_bo_lock.c b/linux-core/drm_bo_lock.c
deleted file mode 100644
index 08b1c6be..00000000
--- a/linux-core/drm_bo_lock.c
+++ /dev/null
@@ -1,189 +0,0 @@
-/**************************************************************************
- *
- * Copyright (c) 2007 Tungsten Graphics, Inc., Cedar Park, TX., USA
- * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
- * THE COPYRIGHT HOLDERS, AUTHORS 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: Thomas Hellström <thomas-at-tungstengraphics-dot-com>
- */
-
-/*
- * This file implements a simple replacement for the buffer manager use
- * of the heavyweight hardware lock.
- * The lock is a read-write lock. Taking it in read mode is fast, and
- * intended for in-kernel use only.
- * Taking it in write mode is slow.
- *
- * The write mode is used only when there is a need to block all
- * user-space processes from allocating a
- * new memory area.
- * Typical use in write mode is X server VT switching, and it's allowed
- * to leave kernel space with the write lock held. If a user-space process
- * dies while having the write-lock, it will be released during the file
- * descriptor release.
- *
- * The read lock is typically placed at the start of an IOCTL- or
- * user-space callable function that may end up allocating a memory area.
- * This includes setstatus, super-ioctls and no_pfn; the latter may move
- * unmappable regions to mappable. It's a bug to leave kernel space with the
- * read lock held.
- *
- * Both read- and write lock taking may be interruptible for low signal-delivery
- * latency. The locking functions will return -EAGAIN if interrupted by a
- * signal.
- *
- * Locking order: The lock should be taken BEFORE any kernel mutexes
- * or spinlocks.
- */
-
-#include "drmP.h"
-
-void drm_bo_init_lock(struct drm_bo_lock *lock)
-{
- DRM_INIT_WAITQUEUE(&lock->queue);
- atomic_set(&lock->write_lock_pending, 0);
- atomic_set(&lock->readers, 0);
-}
-
-void drm_bo_read_unlock(struct drm_bo_lock *lock)
-{
- if (atomic_dec_and_test(&lock->readers))
- wake_up_all(&lock->queue);
-}
-EXPORT_SYMBOL(drm_bo_read_unlock);
-
-int drm_bo_read_lock(struct drm_bo_lock *lock, int interruptible)
-{
- while (unlikely(atomic_read(&lock->write_lock_pending) != 0)) {
- int ret;
-
- if (!interruptible) {
- wait_event(lock->queue,
- atomic_read(&lock->write_lock_pending) == 0);
- continue;
- }
- ret = wait_event_interruptible
- (lock->queue, atomic_read(&lock->write_lock_pending) == 0);
- if (ret)
- return -EAGAIN;
- }
-
- while (unlikely(!atomic_add_unless(&lock->readers, 1, -1))) {
- int ret;
- if (!interruptible) {
- wait_event(lock->queue,
- atomic_read(&lock->readers) != -1);
- continue;
- }
- ret = wait_event_interruptible
- (lock->queue, atomic_read(&lock->readers) != -1);
- if (ret)
- return -EAGAIN;
- }
- return 0;
-}
-EXPORT_SYMBOL(drm_bo_read_lock);
-
-static int __drm_bo_write_unlock(struct drm_bo_lock *lock)
-{
- if (unlikely(atomic_cmpxchg(&lock->readers, -1, 0) != -1))
- return -EINVAL;
- wake_up_all(&lock->queue);
- return 0;
-}
-
-static void drm_bo_write_lock_remove(struct drm_file *file_priv,
- struct drm_user_object *item)
-{
- struct drm_bo_lock *lock = container_of(item, struct drm_bo_lock, base);
- int ret;
-
- ret = __drm_bo_write_unlock(lock);
- BUG_ON(ret);
-}
-
-int drm_bo_write_lock(struct drm_bo_lock *lock, int interruptible,
- struct drm_file *file_priv)
-{
- int ret = 0;
- struct drm_device *dev;
-
- atomic_inc(&lock->write_lock_pending);
-
- while (unlikely(atomic_cmpxchg(&lock->readers, 0, -1) != 0)) {
- if (!interruptible) {
- wait_event(lock->queue,
- atomic_read(&lock->readers) == 0);
- continue;
- }
- ret = wait_event_interruptible
- (lock->queue, atomic_read(&lock->readers) == 0);
-
- if (ret) {
- atomic_dec(&lock->write_lock_pending);
- wake_up_all(&lock->queue);
- return -EAGAIN;
- }
- }
-
- /*
- * Add a dummy user-object, the destructor of which will
- * make sure the lock is released if the client dies
- * while holding it.
- */
-
- if (atomic_dec_and_test(&lock->write_lock_pending))
- wake_up_all(&lock->queue);
- dev = file_priv->minor->dev;
- mutex_lock(&dev->struct_mutex);
- ret = drm_add_user_object(file_priv, &lock->base, 0);
- lock->base.remove = &drm_bo_write_lock_remove;
- lock->base.type = drm_lock_type;
- if (ret)
- (void)__drm_bo_write_unlock(lock);
-
- mutex_unlock(&dev->struct_mutex);
-
- return ret;
-}
-
-int drm_bo_write_unlock(struct drm_bo_lock *lock, struct drm_file *file_priv)
-{
- struct drm_device *dev = file_priv->minor->dev;
- struct drm_ref_object *ro;
-
- mutex_lock(&dev->struct_mutex);
-
- if (lock->base.owner != file_priv) {
- mutex_unlock(&dev->struct_mutex);
- return -EINVAL;
- }
- ro = drm_lookup_ref_object(file_priv, &lock->base, _DRM_REF_USE);
- BUG_ON(!ro);
- drm_remove_ref_object(file_priv, ro);
- lock->base.owner = NULL;
-
- mutex_unlock(&dev->struct_mutex);
- return 0;
-}