blob: 0998723cde7925b4c9988836b15ddd10e1566820 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/**
Dave Airlieb5e89ed2005-09-25 14:28:13 +10002 * \file drm_lock.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 * IOCTLs for locking
Dave Airlieb5e89ed2005-09-25 14:28:13 +10004 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
7 */
8
9/*
10 * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com
11 *
12 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
15 *
16 * Permission is hereby granted, free of charge, to any person obtaining a
17 * copy of this software and associated documentation files (the "Software"),
18 * to deal in the Software without restriction, including without limitation
19 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
20 * and/or sell copies of the Software, and to permit persons to whom the
21 * Software is furnished to do so, subject to the following conditions:
22 *
23 * The above copyright notice and this permission notice (including the next
24 * paragraph) shall be included in all copies or substantial portions of the
25 * Software.
26 *
27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
28 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
29 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
30 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
31 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
32 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
33 * OTHER DEALINGS IN THE SOFTWARE.
34 */
35
36#include "drmP.h"
37
Dave Airliec94f7022005-07-07 21:03:38 +100038static int drm_notifier(void *priv);
39
Dave Airlieb5e89ed2005-09-25 14:28:13 +100040/**
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 * Lock ioctl.
42 *
43 * \param inode device inode.
Eric Anholt6c340ea2007-08-25 20:23:09 +100044 * \param file_priv DRM file private.
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 * \param cmd command.
46 * \param arg user argument, pointing to a drm_lock structure.
47 * \return zero on success or negative number on failure.
48 *
49 * Add the current task to the lock wait queue, and attempt to take to lock.
50 */
Eric Anholtc153f452007-09-03 12:06:45 +100051int drm_lock(struct drm_device *dev, void *data, struct drm_file *file_priv)
Linus Torvalds1da177e2005-04-16 15:20:36 -070052{
Dave Airlieb5e89ed2005-09-25 14:28:13 +100053 DECLARE_WAITQUEUE(entry, current);
Eric Anholtc153f452007-09-03 12:06:45 +100054 struct drm_lock *lock = data;
Dave Airlieb5e89ed2005-09-25 14:28:13 +100055 int ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
Eric Anholt6c340ea2007-08-25 20:23:09 +100057 ++file_priv->lock_count;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
Eric Anholtc153f452007-09-03 12:06:45 +100059 if (lock->context == DRM_KERNEL_CONTEXT) {
Dave Airlieb5e89ed2005-09-25 14:28:13 +100060 DRM_ERROR("Process %d using kernel context %d\n",
Pavel Emelyanovba25f9d2007-10-18 23:40:40 -070061 task_pid_nr(current), lock->context);
Dave Airlieb5e89ed2005-09-25 14:28:13 +100062 return -EINVAL;
63 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Dave Airlieb5e89ed2005-09-25 14:28:13 +100065 DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n",
Pavel Emelyanovba25f9d2007-10-18 23:40:40 -070066 lock->context, task_pid_nr(current),
Eric Anholtc153f452007-09-03 12:06:45 +100067 dev->lock.hw_lock->lock, lock->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
69 if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE))
Eric Anholtc153f452007-09-03 12:06:45 +100070 if (lock->context < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 return -EINVAL;
72
Dave Airlieb5e89ed2005-09-25 14:28:13 +100073 add_wait_queue(&dev->lock.lock_queue, &entry);
Thomas Hellstromf116cc52008-05-07 12:22:39 +100074 spin_lock_bh(&dev->lock.spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +110075 dev->lock.user_waiters++;
Thomas Hellstromf116cc52008-05-07 12:22:39 +100076 spin_unlock_bh(&dev->lock.spinlock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 for (;;) {
78 __set_current_state(TASK_INTERRUPTIBLE);
Dave Airlieb5e89ed2005-09-25 14:28:13 +100079 if (!dev->lock.hw_lock) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 /* Device has been unregistered */
81 ret = -EINTR;
82 break;
83 }
Eric Anholtc153f452007-09-03 12:06:45 +100084 if (drm_lock_take(&dev->lock, lock->context)) {
Eric Anholt6c340ea2007-08-25 20:23:09 +100085 dev->lock.file_priv = file_priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 dev->lock.lock_time = jiffies;
Dave Airlieb5e89ed2005-09-25 14:28:13 +100087 atomic_inc(&dev->counts[_DRM_STAT_LOCKS]);
88 break; /* Got lock */
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 }
Dave Airlieb5e89ed2005-09-25 14:28:13 +100090
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 /* Contention */
92 schedule();
Dave Airlieb5e89ed2005-09-25 14:28:13 +100093 if (signal_pending(current)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 ret = -ERESTARTSYS;
95 break;
96 }
97 }
Thomas Hellstromf116cc52008-05-07 12:22:39 +100098 spin_lock_bh(&dev->lock.spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +110099 dev->lock.user_waiters--;
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000100 spin_unlock_bh(&dev->lock.spinlock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 __set_current_state(TASK_RUNNING);
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000102 remove_wait_queue(&dev->lock.lock_queue, &entry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103
Eric Anholtc153f452007-09-03 12:06:45 +1000104 DRM_DEBUG("%d %s\n", lock->context,
105 ret ? "interrupted" : "has lock");
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100106 if (ret) return ret;
Dave Airlied985c102006-01-02 21:32:48 +1100107
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000108 sigemptyset(&dev->sigmask);
109 sigaddset(&dev->sigmask, SIGSTOP);
110 sigaddset(&dev->sigmask, SIGTSTP);
111 sigaddset(&dev->sigmask, SIGTTIN);
112 sigaddset(&dev->sigmask, SIGTTOU);
Eric Anholtc153f452007-09-03 12:06:45 +1000113 dev->sigdata.context = lock->context;
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000114 dev->sigdata.lock = dev->lock.hw_lock;
115 block_all_signals(drm_notifier, &dev->sigdata, &dev->sigmask);
116
Eric Anholtc153f452007-09-03 12:06:45 +1000117 if (dev->driver->dma_ready && (lock->flags & _DRM_LOCK_READY))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 dev->driver->dma_ready(dev);
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000119
Eric Anholtc153f452007-09-03 12:06:45 +1000120 if (dev->driver->dma_quiescent && (lock->flags & _DRM_LOCK_QUIESCENT))
121 {
Dave Airlied985c102006-01-02 21:32:48 +1100122 if (dev->driver->dma_quiescent(dev)) {
Eric Anholtc153f452007-09-03 12:06:45 +1000123 DRM_DEBUG("%d waiting for DMA quiescent\n",
124 lock->context);
Eric Anholt20caafa2007-08-25 19:22:43 +1000125 return -EBUSY;
Dave Airlied985c102006-01-02 21:32:48 +1100126 }
127 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000129 if (dev->driver->kernel_context_switch &&
Eric Anholtc153f452007-09-03 12:06:45 +1000130 dev->last_context != lock->context) {
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000131 dev->driver->kernel_context_switch(dev, dev->last_context,
Eric Anholtc153f452007-09-03 12:06:45 +1000132 lock->context);
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000133 }
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100134
Dave Airlied985c102006-01-02 21:32:48 +1100135 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136}
137
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000138/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 * Unlock ioctl.
140 *
141 * \param inode device inode.
Eric Anholt6c340ea2007-08-25 20:23:09 +1000142 * \param file_priv DRM file private.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 * \param cmd command.
144 * \param arg user argument, pointing to a drm_lock structure.
145 * \return zero on success or negative number on failure.
146 *
147 * Transfer and free the lock.
148 */
Eric Anholtc153f452007-09-03 12:06:45 +1000149int drm_unlock(struct drm_device *dev, void *data, struct drm_file *file_priv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150{
Eric Anholtc153f452007-09-03 12:06:45 +1000151 struct drm_lock *lock = data;
Dave Airlie5c2df2b2006-10-24 11:36:59 -0700152 unsigned long irqflags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153
Eric Anholtc153f452007-09-03 12:06:45 +1000154 if (lock->context == DRM_KERNEL_CONTEXT) {
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000155 DRM_ERROR("Process %d using kernel context %d\n",
Pavel Emelyanovba25f9d2007-10-18 23:40:40 -0700156 task_pid_nr(current), lock->context);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 return -EINVAL;
158 }
159
=?utf-8?q?Michel_D=C3=A4nzer?=2e54a002006-10-24 23:08:16 +1000160 spin_lock_irqsave(&dev->tasklet_lock, irqflags);
161
162 if (dev->locked_tasklet_func) {
163 dev->locked_tasklet_func(dev);
164
165 dev->locked_tasklet_func = NULL;
166 }
167
168 spin_unlock_irqrestore(&dev->tasklet_lock, irqflags);
169
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000170 atomic_inc(&dev->counts[_DRM_STAT_UNLOCKS]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171
172 /* kernel_context_switch isn't used by any of the x86 drm
173 * modules but is required by the Sparc driver.
174 */
175 if (dev->driver->kernel_context_switch_unlock)
Dave Airlie0c4dd902006-12-19 17:49:44 +1100176 dev->driver->kernel_context_switch_unlock(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177 else {
Eric Anholtc153f452007-09-03 12:06:45 +1000178 if (drm_lock_free(&dev->lock,lock->context)) {
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100179 /* FIXME: Should really bail out here. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 }
181 }
182
183 unblock_all_signals();
184 return 0;
185}
186
187/**
188 * Take the heavyweight lock.
189 *
190 * \param lock lock pointer.
191 * \param context locking context.
192 * \return one if the lock is held, or zero otherwise.
193 *
194 * Attempt to mark the lock as held by the given context, via the \p cmpxchg instruction.
195 */
Dave Airlie55910512007-07-11 16:53:40 +1000196int drm_lock_take(struct drm_lock_data *lock_data,
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100197 unsigned int context)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198{
199 unsigned int old, new, prev;
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100200 volatile unsigned int *lock = &lock_data->hw_lock->lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000202 spin_lock_bh(&lock_data->spinlock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 do {
204 old = *lock;
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000205 if (old & _DRM_LOCK_HELD)
206 new = old | _DRM_LOCK_CONT;
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100207 else {
208 new = context | _DRM_LOCK_HELD |
209 ((lock_data->user_waiters + lock_data->kernel_waiters > 1) ?
210 _DRM_LOCK_CONT : 0);
211 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 prev = cmpxchg(lock, old, new);
213 } while (prev != old);
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000214 spin_unlock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100215
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 if (_DRM_LOCKING_CONTEXT(old) == context) {
217 if (old & _DRM_LOCK_HELD) {
218 if (context != DRM_KERNEL_CONTEXT) {
219 DRM_ERROR("%d holds heavyweight lock\n",
220 context);
221 }
222 return 0;
223 }
224 }
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100225
226 if ((_DRM_LOCKING_CONTEXT(new)) == context && (new & _DRM_LOCK_HELD)) {
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000227 /* Have lock */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 return 1;
229 }
230 return 0;
231}
232
233/**
234 * This takes a lock forcibly and hands it to context. Should ONLY be used
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000235 * inside *_unlock to give lock to kernel before calling *_dma_schedule.
236 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 * \param dev DRM device.
238 * \param lock lock pointer.
239 * \param context locking context.
240 * \return always one.
241 *
242 * Resets the lock file pointer.
243 * Marks the lock as held by the given context, via the \p cmpxchg instruction.
244 */
Dave Airlie55910512007-07-11 16:53:40 +1000245static int drm_lock_transfer(struct drm_lock_data *lock_data,
Dave Airliec94f7022005-07-07 21:03:38 +1000246 unsigned int context)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247{
248 unsigned int old, new, prev;
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100249 volatile unsigned int *lock = &lock_data->hw_lock->lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250
Eric Anholt6c340ea2007-08-25 20:23:09 +1000251 lock_data->file_priv = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 do {
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000253 old = *lock;
254 new = context | _DRM_LOCK_HELD;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 prev = cmpxchg(lock, old, new);
256 } while (prev != old);
257 return 1;
258}
259
260/**
261 * Free lock.
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000262 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 * \param dev DRM device.
264 * \param lock lock.
265 * \param context context.
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000266 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 * Resets the lock file pointer.
268 * Marks the lock as not held, via the \p cmpxchg instruction. Wakes any task
269 * waiting on the lock queue.
270 */
Dave Airlie55910512007-07-11 16:53:40 +1000271int drm_lock_free(struct drm_lock_data *lock_data, unsigned int context)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272{
273 unsigned int old, new, prev;
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100274 volatile unsigned int *lock = &lock_data->hw_lock->lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000276 spin_lock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100277 if (lock_data->kernel_waiters != 0) {
278 drm_lock_transfer(lock_data, 0);
279 lock_data->idle_has_lock = 1;
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000280 spin_unlock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100281 return 1;
282 }
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000283 spin_unlock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100284
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 do {
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000286 old = *lock;
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100287 new = _DRM_LOCKING_CONTEXT(old);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 prev = cmpxchg(lock, old, new);
289 } while (prev != old);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100290
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 if (_DRM_LOCK_IS_HELD(old) && _DRM_LOCKING_CONTEXT(old) != context) {
292 DRM_ERROR("%d freed heavyweight lock held by %d\n",
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000293 context, _DRM_LOCKING_CONTEXT(old));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 return 1;
295 }
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100296 wake_up_interruptible(&lock_data->lock_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297 return 0;
298}
299
300/**
301 * If we get here, it means that the process has called DRM_IOCTL_LOCK
302 * without calling DRM_IOCTL_UNLOCK.
303 *
304 * If the lock is not held, then let the signal proceed as usual. If the lock
305 * is held, then set the contended flag and keep the signal blocked.
306 *
307 * \param priv pointer to a drm_sigdata structure.
308 * \return one if the signal should be delivered normally, or zero if the
309 * signal should be blocked.
310 */
Dave Airliec94f7022005-07-07 21:03:38 +1000311static int drm_notifier(void *priv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312{
Dave Airlie55910512007-07-11 16:53:40 +1000313 struct drm_sigdata *s = (struct drm_sigdata *) priv;
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000314 unsigned int old, new, prev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000316 /* Allow signal delivery if lock isn't held */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 if (!s->lock || !_DRM_LOCK_IS_HELD(s->lock->lock)
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000318 || _DRM_LOCKING_CONTEXT(s->lock->lock) != s->context)
319 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000321 /* Otherwise, set flag to force call to
322 drmUnlock */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 do {
Dave Airlieb5e89ed2005-09-25 14:28:13 +1000324 old = s->lock->lock;
325 new = old | _DRM_LOCK_CONT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 prev = cmpxchg(&s->lock->lock, old, new);
327 } while (prev != old);
328 return 0;
329}
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100330
331/**
332 * This function returns immediately and takes the hw lock
333 * with the kernel context if it is free, otherwise it gets the highest priority when and if
334 * it is eventually released.
335 *
336 * This guarantees that the kernel will _eventually_ have the lock _unless_ it is held
337 * by a blocked process. (In the latter case an explicit wait for the hardware lock would cause
338 * a deadlock, which is why the "idlelock" was invented).
339 *
340 * This should be sufficient to wait for GPU idle without
341 * having to worry about starvation.
342 */
343
Dave Airlie55910512007-07-11 16:53:40 +1000344void drm_idlelock_take(struct drm_lock_data *lock_data)
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100345{
346 int ret = 0;
347
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000348 spin_lock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100349 lock_data->kernel_waiters++;
350 if (!lock_data->idle_has_lock) {
351
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000352 spin_unlock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100353 ret = drm_lock_take(lock_data, DRM_KERNEL_CONTEXT);
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000354 spin_lock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100355
356 if (ret == 1)
357 lock_data->idle_has_lock = 1;
358 }
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000359 spin_unlock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100360}
361EXPORT_SYMBOL(drm_idlelock_take);
362
Dave Airlie55910512007-07-11 16:53:40 +1000363void drm_idlelock_release(struct drm_lock_data *lock_data)
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100364{
365 unsigned int old, prev;
366 volatile unsigned int *lock = &lock_data->hw_lock->lock;
367
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000368 spin_lock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100369 if (--lock_data->kernel_waiters == 0) {
370 if (lock_data->idle_has_lock) {
371 do {
372 old = *lock;
373 prev = cmpxchg(lock, old, DRM_KERNEL_CONTEXT);
374 } while (prev != old);
375 wake_up_interruptible(&lock_data->lock_queue);
376 lock_data->idle_has_lock = 0;
377 }
378 }
Thomas Hellstromf116cc52008-05-07 12:22:39 +1000379 spin_unlock_bh(&lock_data->spinlock);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100380}
381EXPORT_SYMBOL(drm_idlelock_release);
382
383
Eric Anholtc153f452007-09-03 12:06:45 +1000384int drm_i_have_hw_lock(struct drm_device *dev, struct drm_file *file_priv)
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100385{
Eric Anholt6c340ea2007-08-25 20:23:09 +1000386 return (file_priv->lock_count && dev->lock.hw_lock &&
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100387 _DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) &&
Eric Anholt6c340ea2007-08-25 20:23:09 +1000388 dev->lock.file_priv == file_priv);
Thomas Hellstrom040ac322007-03-23 13:28:33 +1100389}
390
391EXPORT_SYMBOL(drm_i_have_hw_lock);