xref: /titanic_41/usr/src/uts/common/io/drm/drm_context.c (revision ea394cb00fd96864e34d2841b4a22357b621c78f)
1 /*
2  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * drm_context.h -- IOCTLs for generic contexts -*- linux-c -*-
8  * Created: Fri Nov 24 18:31:37 2000 by gareth@valinux.com
9  */
10 /*
11  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
12  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
13  * All Rights Reserved.
14  *
15  * Permission is hereby granted, free of charge, to any person obtaining a
16  * copy of this software and associated documentation files (the "Software"),
17  * to deal in the Software without restriction, including without limitation
18  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
19  * and/or sell copies of the Software, and to permit persons to whom the
20  * Software is furnished to do so, subject to the following conditions:
21  *
22  * The above copyright notice and this permission notice (including the next
23  * paragraph) shall be included in all copies or substantial portions of the
24  * Software.
25  *
26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
27  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
28  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
29  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
30  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
31  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
32  * OTHER DEALINGS IN THE SOFTWARE.
33  *
34  * Authors:
35  *    Rickard E. (Rik) Faith <faith@valinux.com>
36  *    Gareth Hughes <gareth@valinux.com>
37  *
38  */
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 #include "drmP.h"
43 #include "drm_io32.h"
44 
45 static inline int
46 find_first_zero_bit(volatile void *p, int max)
47 {
48 	int b;
49 	volatile int *ptr = (volatile int *)p;
50 
51 	for (b = 0; b < max; b += 32) {
52 		if (ptr[b >> 5] != ~0) {
53 			for (;;) {
54 				if ((ptr[b >> 5] & (1 << (b & 0x1f))) == 0)
55 					return (b);
56 				b++;
57 			}
58 		}
59 	}
60 	return (max);
61 }
62 
63 /*
64  * Context bitmap support
65  */
66 void
67 drm_ctxbitmap_free(drm_device_t *dev, int ctx_handle)
68 {
69 	if (ctx_handle < 0 || ctx_handle >= DRM_MAX_CTXBITMAP ||
70 	    dev->ctx_bitmap == NULL) {
71 		DRM_ERROR("drm_ctxbitmap_free: Attempt to free\
72 		    invalid context handle: %d\n",
73 		    ctx_handle);
74 		return;
75 	}
76 
77 	DRM_LOCK();
78 	clear_bit(ctx_handle, dev->ctx_bitmap);
79 	dev->context_sareas[ctx_handle] = NULL;
80 	DRM_UNLOCK();
81 }
82 
83 /* Is supposed to return -1 if  any error by calling functions */
84 int
85 drm_ctxbitmap_next(drm_device_t *dev)
86 {
87 	int bit;
88 
89 	if (dev->ctx_bitmap == NULL)
90 		return (-1);
91 
92 	DRM_LOCK();
93 	bit = find_first_zero_bit(dev->ctx_bitmap, DRM_MAX_CTXBITMAP);
94 	if (bit >= DRM_MAX_CTXBITMAP) {
95 		DRM_UNLOCK();
96 		return (-1);
97 	}
98 
99 	set_bit(bit, dev->ctx_bitmap);
100 	DRM_DEBUG("drm_ctxbitmap_next: bit : %d", bit);
101 	if ((bit+1) > dev->max_context) {
102 		dev->max_context = (bit+1);
103 		if (dev->context_sareas != NULL) {
104 			drm_local_map_t **ctx_sareas;
105 			ctx_sareas = drm_realloc(dev->context_sareas,
106 			    (dev->max_context - 1) *
107 			    sizeof (*dev->context_sareas),
108 			    dev->max_context *
109 			    sizeof (*dev->context_sareas),
110 			    DRM_MEM_MAPS);
111 			if (ctx_sareas == NULL) {
112 				clear_bit(bit, dev->ctx_bitmap);
113 				DRM_UNLOCK();
114 				return (-1);
115 			}
116 			dev->context_sareas = ctx_sareas;
117 			dev->context_sareas[bit] = NULL;
118 		} else {
119 			/* max_context == 1 at this point */
120 			dev->context_sareas = drm_alloc(dev->max_context *
121 			    sizeof (*dev->context_sareas), KM_NOSLEEP);
122 			if (dev->context_sareas == NULL) {
123 				clear_bit(bit, dev->ctx_bitmap);
124 				DRM_UNLOCK();
125 				return (-1);
126 			}
127 			dev->context_sareas[bit] = NULL;
128 		}
129 	}
130 	DRM_UNLOCK();
131 	DRM_DEBUG("drm_ctxbitmap_next: return %d", bit);
132 	return (bit);
133 }
134 
135 int
136 drm_ctxbitmap_init(drm_device_t *dev)
137 {
138 	int i;
139 	int temp;
140 
141 	DRM_LOCK();
142 	dev->ctx_bitmap = drm_calloc(1, DRM_PAGE_SIZE, DRM_MEM_CTXBITMAP);
143 	if (dev->ctx_bitmap == NULL) {
144 		DRM_UNLOCK();
145 		return (ENOMEM);
146 	}
147 	dev->context_sareas = NULL;
148 	dev->max_context = -1;
149 	DRM_UNLOCK();
150 
151 	for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
152 		temp = drm_ctxbitmap_next(dev);
153 		DRM_DEBUG("drm_ctxbitmap_init : %d", temp);
154 	}
155 	return (0);
156 }
157 
158 void
159 drm_ctxbitmap_cleanup(drm_device_t *dev)
160 {
161 	DRM_LOCK();
162 	if (dev->context_sareas != NULL)
163 		drm_free(dev->context_sareas,
164 		    sizeof (*dev->context_sareas) *
165 		    dev->max_context,
166 		    DRM_MEM_MAPS);
167 	drm_free(dev->ctx_bitmap, DRM_PAGE_SIZE, DRM_MEM_CTXBITMAP);
168 	DRM_UNLOCK();
169 }
170 
171 /*
172  * Per Context SAREA Support
173  */
174 /*ARGSUSED*/
175 int
176 drm_getsareactx(DRM_IOCTL_ARGS)
177 {
178 	DRM_DEVICE;
179 	drm_ctx_priv_map_t request;
180 	drm_local_map_t *map;
181 
182 #ifdef	_MULTI_DATAMODEL
183 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
184 		drm_ctx_priv_map_32_t request32;
185 		DRM_COPYFROM_WITH_RETURN(&request32, (void *)data,
186 		    sizeof (drm_ctx_priv_map_32_t));
187 		request.ctx_id = request32.ctx_id;
188 		request.handle = (void *)(uintptr_t)request32.handle;
189 	} else
190 #endif
191 		DRM_COPYFROM_WITH_RETURN(&request, (void *)data,
192 		    sizeof (request));
193 
194 	DRM_LOCK();
195 	if (dev->max_context < 0 || request.ctx_id >= (unsigned)
196 	    dev->max_context) {
197 		DRM_UNLOCK();
198 		return (EINVAL);
199 	}
200 
201 	map = dev->context_sareas[request.ctx_id];
202 	DRM_UNLOCK();
203 
204 	if (!map)
205 		return (EINVAL);
206 
207 	request.handle = map->handle;
208 
209 #ifdef	_MULTI_DATAMODEL
210 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
211 		drm_ctx_priv_map_32_t request32;
212 		request32.ctx_id = request.ctx_id;
213 		request32.handle = (caddr32_t)(uintptr_t)request.handle;
214 		DRM_COPYTO_WITH_RETURN((void *)data, &request32,
215 		    sizeof (drm_ctx_priv_map_32_t));
216 	} else
217 #endif
218 		DRM_COPYTO_WITH_RETURN((void *)data,
219 		    &request, sizeof (request));
220 
221 	return (0);
222 }
223 
224 /*ARGSUSED*/
225 int
226 drm_setsareactx(DRM_IOCTL_ARGS)
227 {
228 	DRM_DEVICE;
229 	drm_ctx_priv_map_t request;
230 	drm_local_map_t *map = NULL;
231 
232 #ifdef	_MULTI_DATAMODEL
233 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
234 		drm_ctx_priv_map_32_t request32;
235 
236 		DRM_COPYFROM_WITH_RETURN(&request32, (void *)data,
237 		    sizeof (drm_ctx_priv_map_32_t));
238 		request.ctx_id = request32.ctx_id;
239 		request.handle = (void *)(uintptr_t)request32.handle;
240 	} else
241 #endif
242 		DRM_COPYFROM_WITH_RETURN(&request,
243 		    (void *)data, sizeof (request));
244 
245 	DRM_LOCK();
246 	TAILQ_FOREACH(map, &dev->maplist, link) {
247 		if (map->handle == request.handle) {
248 			if (dev->max_context < 0)
249 				goto bad;
250 			if (request.ctx_id >= (unsigned)dev->max_context)
251 				goto bad;
252 			dev->context_sareas[request.ctx_id] = map;
253 			DRM_UNLOCK();
254 			return (0);
255 		}
256 	}
257 
258 bad:
259 	DRM_UNLOCK();
260 	return (EINVAL);
261 }
262 
263 /*
264  * The actual DRM context handling routines
265  */
266 int
267 drm_context_switch(drm_device_t *dev, int old, int new)
268 {
269 	if (test_and_set_bit(0, &dev->context_flag)) {
270 		DRM_ERROR("drm_context_switch: Reentering -- FIXME");
271 		return (EBUSY);
272 	}
273 
274 	DRM_DEBUG("drm_context_switch: Context switch from %d to %d",
275 	    old, new);
276 
277 	if (new == dev->last_context) {
278 		clear_bit(0, &dev->context_flag);
279 		return (0);
280 	}
281 
282 	return (0);
283 }
284 
285 int
286 drm_context_switch_complete(drm_device_t *dev, int new)
287 {
288 	dev->last_context = new;  /* PRE/POST: This is the _only_ writer. */
289 
290 	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
291 		DRM_ERROR(
292 		    "drm_context_switch_complete: Lock not held");
293 	}
294 	/*
295 	 * If a context switch is ever initiated
296 	 * when the kernel holds the lock, release
297 	 * that lock here.
298 	 */
299 	clear_bit(0, &dev->context_flag);
300 
301 	return (0);
302 }
303 
304 /*ARGSUSED*/
305 int
306 drm_resctx(DRM_IOCTL_ARGS)
307 {
308 	drm_ctx_res_t res;
309 	drm_ctx_t ctx;
310 	int i;
311 
312 #ifdef	_MULTI_DATAMODEL
313 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
314 		drm_ctx_res_32_t res32;
315 		DRM_COPYFROM_WITH_RETURN(&res32, (void *)data, sizeof (res32));
316 		res.count = res32.count;
317 		res.contexts = (drm_ctx_t *)(uintptr_t)res32.contexts;
318 	} else
319 #endif
320 		DRM_COPYFROM_WITH_RETURN(&res, (void *)data, sizeof (res));
321 
322 	if (res.count >= DRM_RESERVED_CONTEXTS) {
323 		bzero(&ctx, sizeof (ctx));
324 		for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
325 			ctx.handle = i;
326 			DRM_COPYTO_WITH_RETURN(&res.contexts[i],
327 			    &ctx, sizeof (ctx));
328 		}
329 	}
330 	res.count = DRM_RESERVED_CONTEXTS;
331 
332 #ifdef	_MULTI_DATAMODEL
333 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
334 		drm_ctx_res_32_t res32;
335 		res32.count = res.count;
336 		res32.contexts = (caddr32_t)(uintptr_t)res.contexts;
337 
338 		DRM_COPYTO_WITH_RETURN((void *)data, &res32,
339 		    sizeof (drm_ctx_res_32_t));
340 	} else
341 #endif
342 		DRM_COPYTO_WITH_RETURN((void *)data, &res, sizeof (res));
343 
344 	return (0);
345 }
346 
347 /*ARGSUSED*/
348 int
349 drm_addctx(DRM_IOCTL_ARGS)
350 {
351 	DRM_DEVICE;
352 	drm_ctx_t ctx;
353 
354 	DRM_COPYFROM_WITH_RETURN(&ctx, (void *)data, sizeof (ctx));
355 
356 	ctx.handle = drm_ctxbitmap_next(dev);
357 	if (ctx.handle == DRM_KERNEL_CONTEXT) {
358 		/* Skip kernel's context and get a new one. */
359 		ctx.handle = drm_ctxbitmap_next(dev);
360 	}
361 	if (ctx.handle == (drm_context_t)-1) {
362 		return (ENOMEM);
363 	}
364 
365 	if (dev->driver->context_ctor && ctx.handle != DRM_KERNEL_CONTEXT) {
366 		dev->driver->context_ctor(dev, ctx.handle);
367 	}
368 
369 	DRM_COPYTO_WITH_RETURN((void *)data, &ctx, sizeof (ctx));
370 
371 	return (0);
372 }
373 
374 /*ARGSUSED*/
375 int
376 drm_modctx(DRM_IOCTL_ARGS)
377 {
378 	/* This does nothing */
379 	return (0);
380 }
381 
382 /*ARGSUSED*/
383 int
384 drm_getctx(DRM_IOCTL_ARGS)
385 {
386 	drm_ctx_t ctx;
387 
388 	DRM_COPYFROM_WITH_RETURN(&ctx, (void *)data, sizeof (ctx));
389 
390 	/* This is 0, because we don't handle any context flags */
391 	ctx.flags = 0;
392 
393 	DRM_COPYTO_WITH_RETURN((void *)data, &ctx, sizeof (ctx));
394 
395 	return (0);
396 }
397 
398 /*ARGSUSED*/
399 int
400 drm_switchctx(DRM_IOCTL_ARGS)
401 {
402 	DRM_DEVICE;
403 	drm_ctx_t ctx;
404 
405 	DRM_COPYFROM_WITH_RETURN(&ctx, (void *)data, sizeof (ctx));
406 
407 	DRM_DEBUG("drm_switchctx: %d", ctx.handle);
408 	return (drm_context_switch(dev, dev->last_context, ctx.handle));
409 }
410 
411 /*ARGSUSED*/
412 int
413 drm_newctx(DRM_IOCTL_ARGS)
414 {
415 	DRM_DEVICE;
416 	drm_ctx_t ctx;
417 
418 	DRM_COPYFROM_WITH_RETURN(&ctx, (void *)data, sizeof (ctx));
419 
420 	DRM_DEBUG("drm_newctx: %d", ctx.handle);
421 	(void) drm_context_switch_complete(dev, ctx.handle);
422 
423 	return (0);
424 }
425 
426 /*ARGSUSED*/
427 int
428 drm_rmctx(DRM_IOCTL_ARGS)
429 {
430 	DRM_DEVICE;
431 	drm_ctx_t ctx;
432 
433 	DRM_COPYFROM_WITH_RETURN(&ctx, (void *)data, sizeof (ctx));
434 
435 	DRM_DEBUG("drm_rmctx : %d", ctx.handle);
436 	if (ctx.handle != DRM_KERNEL_CONTEXT) {
437 		if (dev->driver->context_dtor) {
438 			DRM_LOCK();
439 			dev->driver->context_dtor(dev, ctx.handle);
440 			DRM_UNLOCK();
441 		}
442 
443 		drm_ctxbitmap_free(dev, ctx.handle);
444 	}
445 
446 	return (0);
447 }
448