summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/drm_lock.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpu/drm/drm_lock.c')
-rw-r--r--drivers/gpu/drm/drm_lock.c373
1 files changed, 0 insertions, 373 deletions
diff --git a/drivers/gpu/drm/drm_lock.c b/drivers/gpu/drm/drm_lock.c
deleted file mode 100644
index 1efbd5389..000000000
--- a/drivers/gpu/drm/drm_lock.c
+++ /dev/null
@@ -1,373 +0,0 @@
-/*
- * \file drm_lock.c
- * IOCTLs for locking
- *
- * \author Rickard E. (Rik) Faith <faith@valinux.com>
- * \author Gareth Hughes <gareth@valinux.com>
- */
-
-/*
- * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com
- *
- * 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.
- */
-
-#include <linux/export.h>
-#include <linux/sched/signal.h>
-
-#include <drm/drm.h>
-#include <drm/drm_drv.h>
-#include <drm/drm_file.h>
-#include <drm/drm_print.h>
-
-#include "drm_internal.h"
-#include "drm_legacy.h"
-
-static int drm_lock_take(struct drm_lock_data *lock_data, unsigned int context);
-
-/*
- * Take the heavyweight lock.
- *
- * \param lock lock pointer.
- * \param context locking context.
- * \return one if the lock is held, or zero otherwise.
- *
- * Attempt to mark the lock as held by the given context, via the \p cmpxchg instruction.
- */
-static
-int drm_lock_take(struct drm_lock_data *lock_data,
- unsigned int context)
-{
- unsigned int old, new, prev;
- volatile unsigned int *lock = &lock_data->hw_lock->lock;
-
- spin_lock_bh(&lock_data->spinlock);
- do {
- old = *lock;
- if (old & _DRM_LOCK_HELD)
- new = old | _DRM_LOCK_CONT;
- else {
- new = context | _DRM_LOCK_HELD |
- ((lock_data->user_waiters + lock_data->kernel_waiters > 1) ?
- _DRM_LOCK_CONT : 0);
- }
- prev = cmpxchg(lock, old, new);
- } while (prev != old);
- spin_unlock_bh(&lock_data->spinlock);
-
- 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 ((_DRM_LOCKING_CONTEXT(new)) == context && (new & _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.
- *
- * \param dev DRM device.
- * \param lock lock pointer.
- * \param context locking context.
- * \return always one.
- *
- * Resets the lock file pointer.
- * Marks the lock as held by the given context, via the \p cmpxchg instruction.
- */
-static int drm_lock_transfer(struct drm_lock_data *lock_data,
- unsigned int context)
-{
- unsigned int old, new, prev;
- volatile unsigned int *lock = &lock_data->hw_lock->lock;
-
- lock_data->file_priv = NULL;
- do {
- old = *lock;
- new = context | _DRM_LOCK_HELD;
- prev = cmpxchg(lock, old, new);
- } while (prev != old);
- return 1;
-}
-
-static int drm_legacy_lock_free(struct drm_lock_data *lock_data,
- unsigned int context)
-{
- unsigned int old, new, prev;
- volatile unsigned int *lock = &lock_data->hw_lock->lock;
-
- spin_lock_bh(&lock_data->spinlock);
- if (lock_data->kernel_waiters != 0) {
- drm_lock_transfer(lock_data, 0);
- lock_data->idle_has_lock = 1;
- spin_unlock_bh(&lock_data->spinlock);
- return 1;
- }
- spin_unlock_bh(&lock_data->spinlock);
-
- do {
- old = *lock;
- new = _DRM_LOCKING_CONTEXT(old);
- 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));
- return 1;
- }
- wake_up_interruptible(&lock_data->lock_queue);
- return 0;
-}
-
-/*
- * Lock ioctl.
- *
- * \param inode device inode.
- * \param file_priv DRM file private.
- * \param cmd command.
- * \param arg user argument, pointing to a drm_lock structure.
- * \return zero on success or negative number on failure.
- *
- * Add the current task to the lock wait queue, and attempt to take to lock.
- */
-int drm_legacy_lock(struct drm_device *dev, void *data,
- struct drm_file *file_priv)
-{
- DECLARE_WAITQUEUE(entry, current);
- struct drm_lock *lock = data;
- struct drm_master *master = file_priv->master;
- int ret = 0;
-
- if (!drm_core_check_feature(dev, DRIVER_LEGACY))
- return -EOPNOTSUPP;
-
- ++file_priv->lock_count;
-
- if (lock->context == DRM_KERNEL_CONTEXT) {
- DRM_ERROR("Process %d using kernel context %d\n",
- task_pid_nr(current), lock->context);
- return -EINVAL;
- }
-
- DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n",
- lock->context, task_pid_nr(current),
- master->lock.hw_lock ? master->lock.hw_lock->lock : -1,
- lock->flags);
-
- add_wait_queue(&master->lock.lock_queue, &entry);
- spin_lock_bh(&master->lock.spinlock);
- master->lock.user_waiters++;
- spin_unlock_bh(&master->lock.spinlock);
-
- for (;;) {
- __set_current_state(TASK_INTERRUPTIBLE);
- if (!master->lock.hw_lock) {
- /* Device has been unregistered */
- send_sig(SIGTERM, current, 0);
- ret = -EINTR;
- break;
- }
- if (drm_lock_take(&master->lock, lock->context)) {
- master->lock.file_priv = file_priv;
- master->lock.lock_time = jiffies;
- break; /* Got lock */
- }
-
- /* Contention */
- mutex_unlock(&drm_global_mutex);
- schedule();
- mutex_lock(&drm_global_mutex);
- if (signal_pending(current)) {
- ret = -EINTR;
- break;
- }
- }
- spin_lock_bh(&master->lock.spinlock);
- master->lock.user_waiters--;
- spin_unlock_bh(&master->lock.spinlock);
- __set_current_state(TASK_RUNNING);
- remove_wait_queue(&master->lock.lock_queue, &entry);
-
- DRM_DEBUG("%d %s\n", lock->context,
- ret ? "interrupted" : "has lock");
- if (ret) return ret;
-
- /* don't set the block all signals on the master process for now
- * really probably not the correct answer but lets us debug xkb
- * xserver for now */
- if (!drm_is_current_master(file_priv)) {
- dev->sigdata.context = lock->context;
- dev->sigdata.lock = master->lock.hw_lock;
- }
-
- 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 -EBUSY;
- }
- }
-
- return 0;
-}
-
-/*
- * Unlock ioctl.
- *
- * \param inode device inode.
- * \param file_priv DRM file private.
- * \param cmd command.
- * \param arg user argument, pointing to a drm_lock structure.
- * \return zero on success or negative number on failure.
- *
- * Transfer and free the lock.
- */
-int drm_legacy_unlock(struct drm_device *dev, void *data, struct drm_file *file_priv)
-{
- struct drm_lock *lock = data;
- struct drm_master *master = file_priv->master;
-
- if (!drm_core_check_feature(dev, DRIVER_LEGACY))
- return -EOPNOTSUPP;
-
- if (lock->context == DRM_KERNEL_CONTEXT) {
- DRM_ERROR("Process %d using kernel context %d\n",
- task_pid_nr(current), lock->context);
- return -EINVAL;
- }
-
- if (drm_legacy_lock_free(&master->lock, lock->context)) {
- /* FIXME: Should really bail out here. */
- }
-
- return 0;
-}
-
-/*
- * This function returns immediately and takes the hw lock
- * with the kernel context if it is free, otherwise it gets the highest priority when and if
- * it is eventually released.
- *
- * This guarantees that the kernel will _eventually_ have the lock _unless_ it is held
- * by a blocked process. (In the latter case an explicit wait for the hardware lock would cause
- * a deadlock, which is why the "idlelock" was invented).
- *
- * This should be sufficient to wait for GPU idle without
- * having to worry about starvation.
- */
-void drm_legacy_idlelock_take(struct drm_lock_data *lock_data)
-{
- int ret;
-
- spin_lock_bh(&lock_data->spinlock);
- lock_data->kernel_waiters++;
- if (!lock_data->idle_has_lock) {
-
- spin_unlock_bh(&lock_data->spinlock);
- ret = drm_lock_take(lock_data, DRM_KERNEL_CONTEXT);
- spin_lock_bh(&lock_data->spinlock);
-
- if (ret == 1)
- lock_data->idle_has_lock = 1;
- }
- spin_unlock_bh(&lock_data->spinlock);
-}
-EXPORT_SYMBOL(drm_legacy_idlelock_take);
-
-void drm_legacy_idlelock_release(struct drm_lock_data *lock_data)
-{
- unsigned int old, prev;
- volatile unsigned int *lock = &lock_data->hw_lock->lock;
-
- spin_lock_bh(&lock_data->spinlock);
- if (--lock_data->kernel_waiters == 0) {
- if (lock_data->idle_has_lock) {
- do {
- old = *lock;
- prev = cmpxchg(lock, old, DRM_KERNEL_CONTEXT);
- } while (prev != old);
- wake_up_interruptible(&lock_data->lock_queue);
- lock_data->idle_has_lock = 0;
- }
- }
- spin_unlock_bh(&lock_data->spinlock);
-}
-EXPORT_SYMBOL(drm_legacy_idlelock_release);
-
-static int drm_legacy_i_have_hw_lock(struct drm_device *dev,
- struct drm_file *file_priv)
-{
- struct drm_master *master = file_priv->master;
-
- return (file_priv->lock_count && master->lock.hw_lock &&
- _DRM_LOCK_IS_HELD(master->lock.hw_lock->lock) &&
- master->lock.file_priv == file_priv);
-}
-
-void drm_legacy_lock_release(struct drm_device *dev, struct file *filp)
-{
- struct drm_file *file_priv = filp->private_data;
-
- /* if the master has gone away we can't do anything with the lock */
- if (!dev->master)
- return;
-
- if (drm_legacy_i_have_hw_lock(dev, file_priv)) {
- DRM_DEBUG("File %p released, freeing lock for context %d\n",
- filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
- drm_legacy_lock_free(&file_priv->master->lock,
- _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
- }
-}
-
-void drm_legacy_lock_master_cleanup(struct drm_device *dev, struct drm_master *master)
-{
- if (!drm_core_check_feature(dev, DRIVER_LEGACY))
- return;
-
- /*
- * Since the master is disappearing, so is the
- * possibility to lock.
- */
- mutex_lock(&dev->struct_mutex);
- if (master->lock.hw_lock) {
- if (dev->sigdata.lock == master->lock.hw_lock)
- dev->sigdata.lock = NULL;
- master->lock.hw_lock = NULL;
- master->lock.file_priv = NULL;
- wake_up_interruptible_all(&master->lock.lock_queue);
- }
- mutex_unlock(&dev->struct_mutex);
-}