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-rw-r--r--drivers/gpu/drm/ttm/Makefile2
-rw-r--r--drivers/gpu/drm/ttm/ttm_lock.c311
-rw-r--r--include/drm/ttm/ttm_lock.h247
3 files changed, 559 insertions, 1 deletions
diff --git a/drivers/gpu/drm/ttm/Makefile b/drivers/gpu/drm/ttm/Makefile
index a9cc9f895360..4473549bc5d2 100644
--- a/drivers/gpu/drm/ttm/Makefile
+++ b/drivers/gpu/drm/ttm/Makefile
@@ -4,6 +4,6 @@
4ccflags-y := -Iinclude/drm 4ccflags-y := -Iinclude/drm
5ttm-y := ttm_agp_backend.o ttm_memory.o ttm_tt.o ttm_bo.o \ 5ttm-y := ttm_agp_backend.o ttm_memory.o ttm_tt.o ttm_bo.o \
6 ttm_bo_util.o ttm_bo_vm.o ttm_module.o ttm_global.o \ 6 ttm_bo_util.o ttm_bo_vm.o ttm_module.o ttm_global.o \
7 ttm_object.o 7 ttm_object.o ttm_lock.o
8 8
9obj-$(CONFIG_DRM_TTM) += ttm.o 9obj-$(CONFIG_DRM_TTM) += ttm.o
diff --git a/drivers/gpu/drm/ttm/ttm_lock.c b/drivers/gpu/drm/ttm/ttm_lock.c
new file mode 100644
index 000000000000..f619ebcaa4ec
--- /dev/null
+++ b/drivers/gpu/drm/ttm/ttm_lock.c
@@ -0,0 +1,311 @@
1/**************************************************************************
2 *
3 * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31#include "ttm/ttm_lock.h"
32#include "ttm/ttm_module.h"
33#include <asm/atomic.h>
34#include <linux/errno.h>
35#include <linux/wait.h>
36#include <linux/sched.h>
37#include <linux/module.h>
38
39#define TTM_WRITE_LOCK_PENDING (1 << 0)
40#define TTM_VT_LOCK_PENDING (1 << 1)
41#define TTM_SUSPEND_LOCK_PENDING (1 << 2)
42#define TTM_VT_LOCK (1 << 3)
43#define TTM_SUSPEND_LOCK (1 << 4)
44
45void ttm_lock_init(struct ttm_lock *lock)
46{
47 spin_lock_init(&lock->lock);
48 init_waitqueue_head(&lock->queue);
49 lock->rw = 0;
50 lock->flags = 0;
51 lock->kill_takers = false;
52 lock->signal = SIGKILL;
53}
54EXPORT_SYMBOL(ttm_lock_init);
55
56void ttm_read_unlock(struct ttm_lock *lock)
57{
58 spin_lock(&lock->lock);
59 if (--lock->rw == 0)
60 wake_up_all(&lock->queue);
61 spin_unlock(&lock->lock);
62}
63EXPORT_SYMBOL(ttm_read_unlock);
64
65static bool __ttm_read_lock(struct ttm_lock *lock)
66{
67 bool locked = false;
68
69 spin_lock(&lock->lock);
70 if (unlikely(lock->kill_takers)) {
71 send_sig(lock->signal, current, 0);
72 spin_unlock(&lock->lock);
73 return false;
74 }
75 if (lock->rw >= 0 && lock->flags == 0) {
76 ++lock->rw;
77 locked = true;
78 }
79 spin_unlock(&lock->lock);
80 return locked;
81}
82
83int ttm_read_lock(struct ttm_lock *lock, bool interruptible)
84{
85 int ret = 0;
86
87 if (interruptible)
88 ret = wait_event_interruptible(lock->queue,
89 __ttm_read_lock(lock));
90 else
91 wait_event(lock->queue, __ttm_read_lock(lock));
92 return ret;
93}
94EXPORT_SYMBOL(ttm_read_lock);
95
96static bool __ttm_read_trylock(struct ttm_lock *lock, bool *locked)
97{
98 bool block = true;
99
100 *locked = false;
101
102 spin_lock(&lock->lock);
103 if (unlikely(lock->kill_takers)) {
104 send_sig(lock->signal, current, 0);
105 spin_unlock(&lock->lock);
106 return false;
107 }
108 if (lock->rw >= 0 && lock->flags == 0) {
109 ++lock->rw;
110 block = false;
111 *locked = true;
112 } else if (lock->flags == 0) {
113 block = false;
114 }
115 spin_unlock(&lock->lock);
116
117 return !block;
118}
119
120int ttm_read_trylock(struct ttm_lock *lock, bool interruptible)
121{
122 int ret = 0;
123 bool locked;
124
125 if (interruptible)
126 ret = wait_event_interruptible
127 (lock->queue, __ttm_read_trylock(lock, &locked));
128 else
129 wait_event(lock->queue, __ttm_read_trylock(lock, &locked));
130
131 if (unlikely(ret != 0)) {
132 BUG_ON(locked);
133 return ret;
134 }
135
136 return (locked) ? 0 : -EBUSY;
137}
138
139void ttm_write_unlock(struct ttm_lock *lock)
140{
141 spin_lock(&lock->lock);
142 lock->rw = 0;
143 wake_up_all(&lock->queue);
144 spin_unlock(&lock->lock);
145}
146EXPORT_SYMBOL(ttm_write_unlock);
147
148static bool __ttm_write_lock(struct ttm_lock *lock)
149{
150 bool locked = false;
151
152 spin_lock(&lock->lock);
153 if (unlikely(lock->kill_takers)) {
154 send_sig(lock->signal, current, 0);
155 spin_unlock(&lock->lock);
156 return false;
157 }
158 if (lock->rw == 0 && ((lock->flags & ~TTM_WRITE_LOCK_PENDING) == 0)) {
159 lock->rw = -1;
160 lock->flags &= ~TTM_WRITE_LOCK_PENDING;
161 locked = true;
162 } else {
163 lock->flags |= TTM_WRITE_LOCK_PENDING;
164 }
165 spin_unlock(&lock->lock);
166 return locked;
167}
168
169int ttm_write_lock(struct ttm_lock *lock, bool interruptible)
170{
171 int ret = 0;
172
173 if (interruptible) {
174 ret = wait_event_interruptible(lock->queue,
175 __ttm_write_lock(lock));
176 if (unlikely(ret != 0)) {
177 spin_lock(&lock->lock);
178 lock->flags &= ~TTM_WRITE_LOCK_PENDING;
179 wake_up_all(&lock->queue);
180 spin_unlock(&lock->lock);
181 }
182 } else
183 wait_event(lock->queue, __ttm_read_lock(lock));
184
185 return ret;
186}
187EXPORT_SYMBOL(ttm_write_lock);
188
189void ttm_write_lock_downgrade(struct ttm_lock *lock)
190{
191 spin_lock(&lock->lock);
192 lock->rw = 1;
193 wake_up_all(&lock->queue);
194 spin_unlock(&lock->lock);
195}
196
197static int __ttm_vt_unlock(struct ttm_lock *lock)
198{
199 int ret = 0;
200
201 spin_lock(&lock->lock);
202 if (unlikely(!(lock->flags & TTM_VT_LOCK)))
203 ret = -EINVAL;
204 lock->flags &= ~TTM_VT_LOCK;
205 wake_up_all(&lock->queue);
206 spin_unlock(&lock->lock);
207 printk(KERN_INFO TTM_PFX "vt unlock.\n");
208
209 return ret;
210}
211
212static void ttm_vt_lock_remove(struct ttm_base_object **p_base)
213{
214 struct ttm_base_object *base = *p_base;
215 struct ttm_lock *lock = container_of(base, struct ttm_lock, base);
216 int ret;
217
218 *p_base = NULL;
219 ret = __ttm_vt_unlock(lock);
220 BUG_ON(ret != 0);
221}
222
223static bool __ttm_vt_lock(struct ttm_lock *lock)
224{
225 bool locked = false;
226
227 spin_lock(&lock->lock);
228 if (lock->rw == 0) {
229 lock->flags &= ~TTM_VT_LOCK_PENDING;
230 lock->flags |= TTM_VT_LOCK;
231 locked = true;
232 } else {
233 lock->flags |= TTM_VT_LOCK_PENDING;
234 }
235 spin_unlock(&lock->lock);
236 return locked;
237}
238
239int ttm_vt_lock(struct ttm_lock *lock,
240 bool interruptible,
241 struct ttm_object_file *tfile)
242{
243 int ret = 0;
244
245 if (interruptible) {
246 ret = wait_event_interruptible(lock->queue,
247 __ttm_vt_lock(lock));
248 if (unlikely(ret != 0)) {
249 spin_lock(&lock->lock);
250 lock->flags &= ~TTM_VT_LOCK_PENDING;
251 wake_up_all(&lock->queue);
252 spin_unlock(&lock->lock);
253 return ret;
254 }
255 } else
256 wait_event(lock->queue, __ttm_vt_lock(lock));
257
258 /*
259 * Add a base-object, the destructor of which will
260 * make sure the lock is released if the client dies
261 * while holding it.
262 */
263
264 ret = ttm_base_object_init(tfile, &lock->base, false,
265 ttm_lock_type, &ttm_vt_lock_remove, NULL);
266 if (ret)
267 (void)__ttm_vt_unlock(lock);
268 else {
269 lock->vt_holder = tfile;
270 printk(KERN_INFO TTM_PFX "vt lock.\n");
271 }
272
273 return ret;
274}
275EXPORT_SYMBOL(ttm_vt_lock);
276
277int ttm_vt_unlock(struct ttm_lock *lock)
278{
279 return ttm_ref_object_base_unref(lock->vt_holder,
280 lock->base.hash.key, TTM_REF_USAGE);
281}
282EXPORT_SYMBOL(ttm_vt_unlock);
283
284void ttm_suspend_unlock(struct ttm_lock *lock)
285{
286 spin_lock(&lock->lock);
287 lock->flags &= ~TTM_SUSPEND_LOCK;
288 wake_up_all(&lock->queue);
289 spin_unlock(&lock->lock);
290}
291
292static bool __ttm_suspend_lock(struct ttm_lock *lock)
293{
294 bool locked = false;
295
296 spin_lock(&lock->lock);
297 if (lock->rw == 0) {
298 lock->flags &= ~TTM_SUSPEND_LOCK_PENDING;
299 lock->flags |= TTM_SUSPEND_LOCK;
300 locked = true;
301 } else {
302 lock->flags |= TTM_SUSPEND_LOCK_PENDING;
303 }
304 spin_unlock(&lock->lock);
305 return locked;
306}
307
308void ttm_suspend_lock(struct ttm_lock *lock)
309{
310 wait_event(lock->queue, __ttm_suspend_lock(lock));
311}
diff --git a/include/drm/ttm/ttm_lock.h b/include/drm/ttm/ttm_lock.h
new file mode 100644
index 000000000000..81ba0b0b891a
--- /dev/null
+++ b/include/drm/ttm/ttm_lock.h
@@ -0,0 +1,247 @@
1/**************************************************************************
2 *
3 * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31/** @file ttm_lock.h
32 * This file implements a simple replacement for the buffer manager use
33 * of the DRM heavyweight hardware lock.
34 * The lock is a read-write lock. Taking it in read mode and write mode
35 * is relatively fast, and intended for in-kernel use only.
36 *
37 * The vt mode is used only when there is a need to block all
38 * user-space processes from validating buffers.
39 * It's allowed to leave kernel space with the vt lock held.
40 * If a user-space process dies while having the vt-lock,
41 * it will be released during the file descriptor release. The vt lock
42 * excludes write lock and read lock.
43 *
44 * The suspend mode is used to lock out all TTM users when preparing for
45 * and executing suspend operations.
46 *
47 */
48
49#ifndef _TTM_LOCK_H_
50#define _TTM_LOCK_H_
51
52#include "ttm/ttm_object.h"
53#include <linux/wait.h>
54#include <asm/atomic.h>
55
56/**
57 * struct ttm_lock
58 *
59 * @base: ttm base object used solely to release the lock if the client
60 * holding the lock dies.
61 * @queue: Queue for processes waiting for lock change-of-status.
62 * @lock: Spinlock protecting some lock members.
63 * @rw: Read-write lock counter. Protected by @lock.
64 * @flags: Lock state. Protected by @lock.
65 * @kill_takers: Boolean whether to kill takers of the lock.
66 * @signal: Signal to send when kill_takers is true.
67 */
68
69struct ttm_lock {
70 struct ttm_base_object base;
71 wait_queue_head_t queue;
72 spinlock_t lock;
73 int32_t rw;
74 uint32_t flags;
75 bool kill_takers;
76 int signal;
77 struct ttm_object_file *vt_holder;
78};
79
80
81/**
82 * ttm_lock_init
83 *
84 * @lock: Pointer to a struct ttm_lock
85 * Initializes the lock.
86 */
87extern void ttm_lock_init(struct ttm_lock *lock);
88
89/**
90 * ttm_read_unlock
91 *
92 * @lock: Pointer to a struct ttm_lock
93 *
94 * Releases a read lock.
95 */
96extern void ttm_read_unlock(struct ttm_lock *lock);
97
98/**
99 * ttm_read_lock
100 *
101 * @lock: Pointer to a struct ttm_lock
102 * @interruptible: Interruptible sleeping while waiting for a lock.
103 *
104 * Takes the lock in read mode.
105 * Returns:
106 * -ERESTARTSYS If interrupted by a signal and interruptible is true.
107 */
108extern int ttm_read_lock(struct ttm_lock *lock, bool interruptible);
109
110/**
111 * ttm_read_trylock
112 *
113 * @lock: Pointer to a struct ttm_lock
114 * @interruptible: Interruptible sleeping while waiting for a lock.
115 *
116 * Tries to take the lock in read mode. If the lock is already held
117 * in write mode, the function will return -EBUSY. If the lock is held
118 * in vt or suspend mode, the function will sleep until these modes
119 * are unlocked.
120 *
121 * Returns:
122 * -EBUSY The lock was already held in write mode.
123 * -ERESTARTSYS If interrupted by a signal and interruptible is true.
124 */
125extern int ttm_read_trylock(struct ttm_lock *lock, bool interruptible);
126
127/**
128 * ttm_write_unlock
129 *
130 * @lock: Pointer to a struct ttm_lock
131 *
132 * Releases a write lock.
133 */
134extern void ttm_write_unlock(struct ttm_lock *lock);
135
136/**
137 * ttm_write_lock
138 *
139 * @lock: Pointer to a struct ttm_lock
140 * @interruptible: Interruptible sleeping while waiting for a lock.
141 *
142 * Takes the lock in write mode.
143 * Returns:
144 * -ERESTARTSYS If interrupted by a signal and interruptible is true.
145 */
146extern int ttm_write_lock(struct ttm_lock *lock, bool interruptible);
147
148/**
149 * ttm_lock_downgrade
150 *
151 * @lock: Pointer to a struct ttm_lock
152 *
153 * Downgrades a write lock to a read lock.
154 */
155extern void ttm_lock_downgrade(struct ttm_lock *lock);
156
157/**
158 * ttm_suspend_lock
159 *
160 * @lock: Pointer to a struct ttm_lock
161 *
162 * Takes the lock in suspend mode. Excludes read and write mode.
163 */
164extern void ttm_suspend_lock(struct ttm_lock *lock);
165
166/**
167 * ttm_suspend_unlock
168 *
169 * @lock: Pointer to a struct ttm_lock
170 *
171 * Releases a suspend lock
172 */
173extern void ttm_suspend_unlock(struct ttm_lock *lock);
174
175/**
176 * ttm_vt_lock
177 *
178 * @lock: Pointer to a struct ttm_lock
179 * @interruptible: Interruptible sleeping while waiting for a lock.
180 * @tfile: Pointer to a struct ttm_object_file to register the lock with.
181 *
182 * Takes the lock in vt mode.
183 * Returns:
184 * -ERESTARTSYS If interrupted by a signal and interruptible is true.
185 * -ENOMEM: Out of memory when locking.
186 */
187extern int ttm_vt_lock(struct ttm_lock *lock, bool interruptible,
188 struct ttm_object_file *tfile);
189
190/**
191 * ttm_vt_unlock
192 *
193 * @lock: Pointer to a struct ttm_lock
194 *
195 * Releases a vt lock.
196 * Returns:
197 * -EINVAL If the lock was not held.
198 */
199extern int ttm_vt_unlock(struct ttm_lock *lock);
200
201/**
202 * ttm_write_unlock
203 *
204 * @lock: Pointer to a struct ttm_lock
205 *
206 * Releases a write lock.
207 */
208extern void ttm_write_unlock(struct ttm_lock *lock);
209
210/**
211 * ttm_write_lock
212 *
213 * @lock: Pointer to a struct ttm_lock
214 * @interruptible: Interruptible sleeping while waiting for a lock.
215 *
216 * Takes the lock in write mode.
217 * Returns:
218 * -ERESTARTSYS If interrupted by a signal and interruptible is true.
219 */
220extern int ttm_write_lock(struct ttm_lock *lock, bool interruptible);
221
222/**
223 * ttm_lock_set_kill
224 *
225 * @lock: Pointer to a struct ttm_lock
226 * @val: Boolean whether to kill processes taking the lock.
227 * @signal: Signal to send to the process taking the lock.
228 *
229 * The kill-when-taking-lock functionality is used to kill processes that keep
230 * on using the TTM functionality when its resources has been taken down, for
231 * example when the X server exits. A typical sequence would look like this:
232 * - X server takes lock in write mode.
233 * - ttm_lock_set_kill() is called with @val set to true.
234 * - As part of X server exit, TTM resources are taken down.
235 * - X server releases the lock on file release.
236 * - Another dri client wants to render, takes the lock and is killed.
237 *
238 */
239static inline void ttm_lock_set_kill(struct ttm_lock *lock, bool val,
240 int signal)
241{
242 lock->kill_takers = val;
243 if (val)
244 lock->signal = signal;
245}
246
247#endif
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-11 22:25:42 -0500