1 /**
2 * \file drm_context.c
3 * IOCTLs for generic contexts
4 *
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
7 */
8
9 /*
10 * Created: Fri Nov 24 18:31:37 2000 by gareth@valinux.com
11 *
12 * Copyright 1999, 2000 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 /*
37 * ChangeLog:
38 * 2001-11-16 Torsten Duwe <duwe@caldera.de>
39 * added context constructor/destructor hooks,
40 * needed by SiS driver's memory management.
41 */
42
43 #include "drmP.h"
44
45 /******************************************************************/
46 /** \name Context bitmap support */
47 /*@{*/
48
49 /**
50 * Free a handle from the context bitmap.
51 *
52 * \param dev DRM device.
53 * \param ctx_handle context handle.
54 *
55 * Clears the bit specified by \p ctx_handle in drm_device::ctx_bitmap and the entry
56 * in drm_device::ctx_idr, while holding the drm_device::struct_mutex
57 * lock.
58 */
59 void drm_ctxbitmap_free(struct drm_device * dev, int ctx_handle)
60 {
61 mutex_lock(&dev->struct_mutex);
62 idr_remove(&dev->ctx_idr, ctx_handle);
63 mutex_unlock(&dev->struct_mutex);
64 }
65
66 /**
67 * Context bitmap allocation.
68 *
69 * \param dev DRM device.
70 * \return (non-negative) context handle on success or a negative number on failure.
71 *
72 * Allocate a new idr from drm_device::ctx_idr while holding the
73 * drm_device::struct_mutex lock.
74 */
75 static int drm_ctxbitmap_next(struct drm_device * dev)
76 {
77 int new_id;
78 int ret;
79
80 again:
81 if (idr_pre_get(&dev->ctx_idr, GFP_KERNEL) == 0) {
82 DRM_ERROR("Out of memory expanding drawable idr\n");
83 return -ENOMEM;
84 }
85 mutex_lock(&dev->struct_mutex);
86 ret = idr_get_new_above(&dev->ctx_idr, NULL,
87 DRM_RESERVED_CONTEXTS, &new_id);
88 if (ret == -EAGAIN) {
89 mutex_unlock(&dev->struct_mutex);
90 goto again;
91 }
92 mutex_unlock(&dev->struct_mutex);
93 return new_id;
94 }
95
96 /**
97 * Context bitmap initialization.
98 *
99 * \param dev DRM device.
100 *
101 * Initialise the drm_device::ctx_idr
102 */
103 int drm_ctxbitmap_init(struct drm_device * dev)
104 {
105 idr_init(&dev->ctx_idr);
106 return 0;
107 }
108
109 /**
110 * Context bitmap cleanup.
111 *
112 * \param dev DRM device.
113 *
114 * Free all idr members using drm_ctx_sarea_free helper function
115 * while holding the drm_device::struct_mutex lock.
116 */
117 void drm_ctxbitmap_cleanup(struct drm_device * dev)
118 {
119 mutex_lock(&dev->struct_mutex);
120 idr_remove_all(&dev->ctx_idr);
121 mutex_unlock(&dev->struct_mutex);
122 }
123
124 /*@}*/
125
126 /******************************************************************/
127 /** \name Per Context SAREA Support */
128 /*@{*/
129
130 /**
131 * Get per-context SAREA.
132 *
133 * \param inode device inode.
134 * \param file_priv DRM file private.
135 * \param cmd command.
136 * \param arg user argument pointing to a drm_ctx_priv_map structure.
137 * \return zero on success or a negative number on failure.
138 *
139 * Gets the map from drm_device::ctx_idr with the handle specified and
140 * returns its handle.
141 */
142 int drm_getsareactx(struct drm_device *dev, void *data,
143 struct drm_file *file_priv)
144 {
145 struct drm_ctx_priv_map *request = data;
146 struct drm_map *map;
147 struct drm_map_list *_entry;
148
149 mutex_lock(&dev->struct_mutex);
150
151 map = idr_find(&dev->ctx_idr, request->ctx_id);
152 if (!map) {
153 mutex_unlock(&dev->struct_mutex);
154 return -EINVAL;
155 }
156
157 mutex_unlock(&dev->struct_mutex);
158
159 request->handle = NULL;
160 list_for_each_entry(_entry, &dev->maplist, head) {
161 if (_entry->map == map) {
162 request->handle =
163 (void *)(unsigned long)_entry->user_token;
164 break;
165 }
166 }
167 if (request->handle == NULL)
168 return -EINVAL;
169
170 return 0;
171 }
172
173 /**
174 * Set per-context SAREA.
175 *
176 * \param inode device inode.
177 * \param file_priv DRM file private.
178 * \param cmd command.
179 * \param arg user argument pointing to a drm_ctx_priv_map structure.
180 * \return zero on success or a negative number on failure.
181 *
182 * Searches the mapping specified in \p arg and update the entry in
183 * drm_device::ctx_idr with it.
184 */
185 int drm_setsareactx(struct drm_device *dev, void *data,
186 struct drm_file *file_priv)
187 {
188 struct drm_ctx_priv_map *request = data;
189 struct drm_map *map = NULL;
190 struct drm_map_list *r_list = NULL;
191
192 mutex_lock(&dev->struct_mutex);
193 list_for_each_entry(r_list, &dev->maplist, head) {
194 if (r_list->map
195 && r_list->user_token == (unsigned long) request->handle)
196 goto found;
197 }
198 bad:
199 mutex_unlock(&dev->struct_mutex);
200 return -EINVAL;
201
202 found:
203 map = r_list->map;
204 if (!map)
205 goto bad;
206
207 if (IS_ERR(idr_replace(&dev->ctx_idr, map, request->ctx_id)))
208 goto bad;
209
210 mutex_unlock(&dev->struct_mutex);
211
212 return 0;
213 }
214
215 /*@}*/
216
217 /******************************************************************/
218 /** \name The actual DRM context handling routines */
219 /*@{*/
220
221 /**
222 * Switch context.
223 *
224 * \param dev DRM device.
225 * \param old old context handle.
226 * \param new new context handle.
227 * \return zero on success or a negative number on failure.
228 *
229 * Attempt to set drm_device::context_flag.
230 */
231 static int drm_context_switch(struct drm_device * dev, int old, int new)
232 {
233 if (test_and_set_bit(0, &dev->context_flag)) {
234 DRM_ERROR("Reentering -- FIXME\n");
235 return -EBUSY;
236 }
237
238 DRM_DEBUG("Context switch from %d to %d\n", old, new);
239
240 if (new == dev->last_context) {
241 clear_bit(0, &dev->context_flag);
242 return 0;
243 }
244
245 return 0;
246 }
247
248 /**
249 * Complete context switch.
250 *
251 * \param dev DRM device.
252 * \param new new context handle.
253 * \return zero on success or a negative number on failure.
254 *
255 * Updates drm_device::last_context and drm_device::last_switch. Verifies the
256 * hardware lock is held, clears the drm_device::context_flag and wakes up
257 * drm_device::context_wait.
258 */
259 static int drm_context_switch_complete(struct drm_device * dev, int new)
260 {
261 dev->last_context = new; /* PRE/POST: This is the _only_ writer. */
262 dev->last_switch = jiffies;
263
264 if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
265 DRM_ERROR("Lock isn't held after context switch\n");
266 }
267
268 /* If a context switch is ever initiated
269 when the kernel holds the lock, release
270 that lock here. */
271 clear_bit(0, &dev->context_flag);
272 wake_up(&dev->context_wait);
273
274 return 0;
275 }
276
277 /**
278 * Reserve contexts.
279 *
280 * \param inode device inode.
281 * \param file_priv DRM file private.
282 * \param cmd command.
283 * \param arg user argument pointing to a drm_ctx_res structure.
284 * \return zero on success or a negative number on failure.
285 */
286 int drm_resctx(struct drm_device *dev, void *data,
287 struct drm_file *file_priv)
288 {
289 struct drm_ctx_res *res = data;
290 struct drm_ctx ctx;
291 int i;
292
293 if (res->count >= DRM_RESERVED_CONTEXTS) {
294 memset(&ctx, 0, sizeof(ctx));
295 for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
296 ctx.handle = i;
297 if (copy_to_user(&res->contexts[i], &ctx, sizeof(ctx)))
298 return -EFAULT;
299 }
300 }
301 res->count = DRM_RESERVED_CONTEXTS;
302
303 return 0;
304 }
305
306 /**
307 * Add context.
308 *
309 * \param inode device inode.
310 * \param file_priv DRM file private.
311 * \param cmd command.
312 * \param arg user argument pointing to a drm_ctx structure.
313 * \return zero on success or a negative number on failure.
314 *
315 * Get a new handle for the context and copy to userspace.
316 */
317 int drm_addctx(struct drm_device *dev, void *data,
318 struct drm_file *file_priv)
319 {
320 struct drm_ctx_list *ctx_entry;
321 struct drm_ctx *ctx = data;
322
323 ctx->handle = drm_ctxbitmap_next(dev);
324 if (ctx->handle == DRM_KERNEL_CONTEXT) {
325 /* Skip kernel's context and get a new one. */
326 ctx->handle = drm_ctxbitmap_next(dev);
327 }
328 DRM_DEBUG("%d\n", ctx->handle);
329 if (ctx->handle == -1) {
330 DRM_DEBUG("Not enough free contexts.\n");
331 /* Should this return -EBUSY instead? */
332 return -ENOMEM;
333 }
334
335 if (ctx->handle != DRM_KERNEL_CONTEXT) {
336 if (dev->driver->context_ctor)
337 if (!dev->driver->context_ctor(dev, ctx->handle)) {
338 DRM_DEBUG("Running out of ctxs or memory.\n");
339 return -ENOMEM;
340 }
341 }
342
343 ctx_entry = drm_alloc(sizeof(*ctx_entry), DRM_MEM_CTXLIST);
344 if (!ctx_entry) {
345 DRM_DEBUG("out of memory\n");
346 return -ENOMEM;
347 }
348
349 INIT_LIST_HEAD(&ctx_entry->head);
350 ctx_entry->handle = ctx->handle;
351 ctx_entry->tag = file_priv;
352
353 mutex_lock(&dev->ctxlist_mutex);
354 list_add(&ctx_entry->head, &dev->ctxlist);
355 ++dev->ctx_count;
356 mutex_unlock(&dev->ctxlist_mutex);
357
358 return 0;
359 }
360
361 int drm_modctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
362 {
363 /* This does nothing */
364 return 0;
365 }
366
367 /**
368 * Get context.
369 *
370 * \param inode device inode.
371 * \param file_priv DRM file private.
372 * \param cmd command.
373 * \param arg user argument pointing to a drm_ctx structure.
374 * \return zero on success or a negative number on failure.
375 */
376 int drm_getctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
377 {
378 struct drm_ctx *ctx = data;
379
380 /* This is 0, because we don't handle any context flags */
381 ctx->flags = 0;
382
383 return 0;
384 }
385
386 /**
387 * Switch context.
388 *
389 * \param inode device inode.
390 * \param file_priv DRM file private.
391 * \param cmd command.
392 * \param arg user argument pointing to a drm_ctx structure.
393 * \return zero on success or a negative number on failure.
394 *
395 * Calls context_switch().
396 */
397 int drm_switchctx(struct drm_device *dev, void *data,
398 struct drm_file *file_priv)
399 {
400 struct drm_ctx *ctx = data;
401
402 DRM_DEBUG("%d\n", ctx->handle);
403 return drm_context_switch(dev, dev->last_context, ctx->handle);
404 }
405
406 /**
407 * New context.
408 *
409 * \param inode device inode.
410 * \param file_priv DRM file private.
411 * \param cmd command.
412 * \param arg user argument pointing to a drm_ctx structure.
413 * \return zero on success or a negative number on failure.
414 *
415 * Calls context_switch_complete().
416 */
417 int drm_newctx(struct drm_device *dev, void *data,
418 struct drm_file *file_priv)
419 {
420 struct drm_ctx *ctx = data;
421
422 DRM_DEBUG("%d\n", ctx->handle);
423 drm_context_switch_complete(dev, ctx->handle);
424
425 return 0;
426 }
427
428 /**
429 * Remove context.
430 *
431 * \param inode device inode.
432 * \param file_priv DRM file private.
433 * \param cmd command.
434 * \param arg user argument pointing to a drm_ctx structure.
435 * \return zero on success or a negative number on failure.
436 *
437 * If not the special kernel context, calls ctxbitmap_free() to free the specified context.
438 */
439 int drm_rmctx(struct drm_device *dev, void *data,
440 struct drm_file *file_priv)
441 {
442 struct drm_ctx *ctx = data;
443
444 DRM_DEBUG("%d\n", ctx->handle);
445 if (ctx->handle == DRM_KERNEL_CONTEXT + 1) {
446 file_priv->remove_auth_on_close = 1;
447 }
448 if (ctx->handle != DRM_KERNEL_CONTEXT) {
449 if (dev->driver->context_dtor)
450 dev->driver->context_dtor(dev, ctx->handle);
451 drm_ctxbitmap_free(dev, ctx->handle);
452 }
453
454 mutex_lock(&dev->ctxlist_mutex);
455 if (!list_empty(&dev->ctxlist)) {
456 struct drm_ctx_list *pos, *n;
457
458 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
459 if (pos->handle == ctx->handle) {
460 list_del(&pos->head);
461 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
462 --dev->ctx_count;
463 }
464 }
465 }
466 mutex_unlock(&dev->ctxlist_mutex);
467
468 return 0;
469 }
470
471 /*@}*/
472
|
This page was automatically generated by the
LXR engine.
|