sys/dev/drm/drm_context.h

   1 /* drm_context.h -- IOCTLs for generic contexts -*- linux-c -*-
   2  * Created: Fri Nov 24 18:31:37 2000 by gareth@valinux.com
   3  *
   4  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
   5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
   6  * All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the next
  16  * paragraph) shall be included in all copies or substantial portions of the
  17  * Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  25  * OTHER DEALINGS IN THE SOFTWARE.
  26  *
  27  * Authors:
  28  *    Rickard E. (Rik) Faith <faith@valinux.com>
  29  *    Gareth Hughes <gareth@valinux.com>
  30  * $FreeBSD: src/sys/dev/drm/drm_context.h,v 1.4.2.1 2003/04/26 07:05:28 anholt Exp $
  31  * $DragonFly: src/sys/dev/drm/drm_context.h,v 1.2 2003/06/17 06:28:24 dillon Exp $
  32  */
  33
  34 #include "dev/drm/drmP.h"
  35
  36 #if !__HAVE_CTX_BITMAP
  37 #error "__HAVE_CTX_BITMAP must be defined"
  38 #endif
  39
  40 /* ================================================================
  41  * Context bitmap support
  42  */
  43
  44 void DRM(ctxbitmap_free)( drm_device_t *dev, int ctx_handle )
  45 {
  46         if ( ctx_handle < 0 ) goto failed;
  47         if ( !dev->ctx_bitmap ) goto failed;
  48
  49         if ( ctx_handle < DRM_MAX_CTXBITMAP ) {
  50                 DRM_LOCK;
  51                 clear_bit( ctx_handle, dev->ctx_bitmap );
  52                 dev->context_sareas[ctx_handle] = NULL;
  53                 DRM_UNLOCK;
  54                 return;
  55         }
  56 failed:
  57         DRM_ERROR( "Attempt to free invalid context handle: %d\n",
  58                    ctx_handle );
  59         return;
  60 }
  61
  62 int DRM(ctxbitmap_next)( drm_device_t *dev )
  63 {
  64         int bit;
  65
  66         if(!dev->ctx_bitmap) return -1;
  67
  68         DRM_LOCK;
  69         bit = find_first_zero_bit( dev->ctx_bitmap, DRM_MAX_CTXBITMAP );
  70         if ( bit < DRM_MAX_CTXBITMAP ) {
  71                 set_bit( bit, dev->ctx_bitmap );
  72                 DRM_DEBUG( "drm_ctxbitmap_next bit : %d\n", bit );
  73                 if((bit+1) > dev->max_context) {
  74                         dev->max_context = (bit+1);
  75                         if(dev->context_sareas) {
  76                                 drm_local_map_t **ctx_sareas;
  77
  78                                 ctx_sareas = DRM(realloc)(dev->context_sareas,
  79                                                 (dev->max_context - 1) *
  80                                                 sizeof(*dev->context_sareas),
  81                                                 dev->max_context *
  82                                                 sizeof(*dev->context_sareas),
  83                                                 DRM_MEM_MAPS);
  84                                 if(!ctx_sareas) {
  85                                         clear_bit(bit, dev->ctx_bitmap);
  86                                         DRM_UNLOCK;
  87                                         return -1;
  88                                 }
  89                                 dev->context_sareas = ctx_sareas;
  90                                 dev->context_sareas[bit] = NULL;
  91                         } else {
  92                                 /* max_context == 1 at this point */
  93                                 dev->context_sareas = DRM(alloc)(
  94                                                 dev->max_context *
  95                                                 sizeof(*dev->context_sareas),
  96                                                 DRM_MEM_MAPS);
  97                                 if(!dev->context_sareas) {
  98                                         clear_bit(bit, dev->ctx_bitmap);
  99                                         DRM_UNLOCK;
 100                                         return -1;
 101                                 }
 102                                 dev->context_sareas[bit] = NULL;
 103                         }
 104                 }
 105                 DRM_UNLOCK;
 106                 return bit;
 107         }
 108         DRM_UNLOCK;
 109         return -1;
 110 }
 111
 112 int DRM(ctxbitmap_init)( drm_device_t *dev )
 113 {
 114         int i;
 115         int temp;
 116
 117         DRM_LOCK;
 118         dev->ctx_bitmap = (atomic_t *) DRM(alloc)( PAGE_SIZE,
 119                                                         DRM_MEM_CTXBITMAP );
 120         if ( dev->ctx_bitmap == NULL ) {
 121                 DRM_UNLOCK;
 122                 return DRM_ERR(ENOMEM);
 123         }
 124         memset( (void *)dev->ctx_bitmap, 0, PAGE_SIZE );
 125         dev->context_sareas = NULL;
 126         dev->max_context = -1;
 127         DRM_UNLOCK;
 128
 129         for ( i = 0 ; i < DRM_RESERVED_CONTEXTS ; i++ ) {
 130                 temp = DRM(ctxbitmap_next)( dev );
 131                 DRM_DEBUG( "drm_ctxbitmap_init : %d\n", temp );
 132         }
 133
 134         return 0;
 135 }
 136
 137 void DRM(ctxbitmap_cleanup)( drm_device_t *dev )
 138 {
 139         DRM_LOCK;
 140         if( dev->context_sareas ) DRM(free)( dev->context_sareas,
 141                                              sizeof(*dev->context_sareas) *
 142                                              dev->max_context,
 143                                              DRM_MEM_MAPS );
 144         DRM(free)( (void *)dev->ctx_bitmap, PAGE_SIZE, DRM_MEM_CTXBITMAP );
 145         DRM_UNLOCK;
 146 }
 147
 148 /* ================================================================
 149  * Per Context SAREA Support
 150  */
 151
 152 int DRM(getsareactx)( DRM_IOCTL_ARGS )
 153 {
 154         DRM_DEVICE;
 155         drm_ctx_priv_map_t request;
 156         drm_local_map_t *map;
 157
 158         DRM_COPY_FROM_USER_IOCTL( request, (drm_ctx_priv_map_t *)data,
 159                            sizeof(request) );
 160
 161         DRM_LOCK;
 162         if (dev->max_context < 0 || request.ctx_id >= (unsigned) dev->max_context) {
 163                 DRM_UNLOCK;
 164                 return DRM_ERR(EINVAL);
 165         }
 166
 167         map = dev->context_sareas[request.ctx_id];
 168         DRM_UNLOCK;
 169
 170         request.handle = map->handle;
 171
 172         DRM_COPY_TO_USER_IOCTL( (drm_ctx_priv_map_t *)data, request, sizeof(request) );
 173
 174         return 0;
 175 }
 176
 177 int DRM(setsareactx)( DRM_IOCTL_ARGS )
 178 {
 179         DRM_DEVICE;
 180         drm_ctx_priv_map_t request;
 181         drm_local_map_t *map = NULL;
 182         drm_map_list_entry_t *list;
 183
 184         DRM_COPY_FROM_USER_IOCTL( request, (drm_ctx_priv_map_t *)data,
 185                            sizeof(request) );
 186
 187         DRM_LOCK;
 188         TAILQ_FOREACH(list, dev->maplist, link) {
 189                 map=list->map;
 190                 if(map->handle == request.handle) {
 191                         if (dev->max_context < 0)
 192                                 goto bad;
 193                         if (request.ctx_id >= (unsigned) dev->max_context)
 194                                 goto bad;
 195                         dev->context_sareas[request.ctx_id] = map;
 196                         DRM_UNLOCK;
 197                         return 0;
 198                 }
 199         }
 200
 201 bad:
 202         DRM_UNLOCK;
 203         return DRM_ERR(EINVAL);
 204 }
 205
 206 /* ================================================================
 207  * The actual DRM context handling routines
 208  */
 209
 210 int DRM(context_switch)( drm_device_t *dev, int old, int new )
 211 {
 212         if ( test_and_set_bit( 0, &dev->context_flag ) ) {
 213                 DRM_ERROR( "Reentering -- FIXME\n" );
 214                 return DRM_ERR(EBUSY);
 215         }
 216
 217         DRM_DEBUG( "Context switch from %d to %d\n", old, new );
 218
 219         if ( new == dev->last_context ) {
 220                 clear_bit( 0, &dev->context_flag );
 221                 return 0;
 222         }
 223
 224         return 0;
 225 }
 226
 227 int DRM(context_switch_complete)( drm_device_t *dev, int new )
 228 {
 229         dev->last_context = new;  /* PRE/POST: This is the _only_ writer. */
 230
 231         if ( !_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) ) {
 232                 DRM_ERROR( "Lock isn't held after context switch\n" );
 233         }
 234
 235                                 /* If a context switch is ever initiated
 236                                    when the kernel holds the lock, release
 237                                    that lock here. */
 238         clear_bit( 0, &dev->context_flag );
 239
 240         return 0;
 241 }
 242
 243 int DRM(resctx)( DRM_IOCTL_ARGS )
 244 {
 245         drm_ctx_res_t res;
 246         drm_ctx_t ctx;
 247         int i;
 248
 249         DRM_COPY_FROM_USER_IOCTL( res, (drm_ctx_res_t *)data, sizeof(res) );
 250
 251         if ( res.count >= DRM_RESERVED_CONTEXTS ) {
 252                 memset( &ctx, 0, sizeof(ctx) );
 253                 for ( i = 0 ; i < DRM_RESERVED_CONTEXTS ; i++ ) {
 254                         ctx.handle = i;
 255                         if ( DRM_COPY_TO_USER( &res.contexts[i],
 256                                            &i, sizeof(i) ) )
 257                                 return DRM_ERR(EFAULT);
 258                 }
 259         }
 260         res.count = DRM_RESERVED_CONTEXTS;
 261
 262         DRM_COPY_TO_USER_IOCTL( (drm_ctx_res_t *)data, res, sizeof(res) );
 263
 264         return 0;
 265 }
 266
 267 int DRM(addctx)( DRM_IOCTL_ARGS )
 268 {
 269         DRM_DEVICE;
 270         drm_ctx_t ctx;
 271
 272         DRM_COPY_FROM_USER_IOCTL( ctx, (drm_ctx_t *)data, sizeof(ctx) );
 273
 274         ctx.handle = DRM(ctxbitmap_next)( dev );
 275         if ( ctx.handle == DRM_KERNEL_CONTEXT ) {
 276                                 /* Skip kernel's context and get a new one. */
 277                 ctx.handle = DRM(ctxbitmap_next)( dev );
 278         }
 279         DRM_DEBUG( "%d\n", ctx.handle );
 280         if ( ctx.handle == -1 ) {
 281                 DRM_DEBUG( "Not enough free contexts.\n" );
 282                                 /* Should this return -EBUSY instead? */
 283                 return DRM_ERR(ENOMEM);
 284         }
 285
 286         DRM_COPY_TO_USER_IOCTL( (drm_ctx_t *)data, ctx, sizeof(ctx) );
 287
 288         return 0;
 289 }
 290
 291 int DRM(modctx)( DRM_IOCTL_ARGS )
 292 {
 293         /* This does nothing */
 294         return 0;
 295 }
 296
 297 int DRM(getctx)( DRM_IOCTL_ARGS )
 298 {
 299         drm_ctx_t ctx;
 300
 301         DRM_COPY_FROM_USER_IOCTL( ctx, (drm_ctx_t *)data, sizeof(ctx) );
 302
 303         /* This is 0, because we don't handle any context flags */
 304         ctx.flags = 0;
 305
 306         DRM_COPY_TO_USER_IOCTL( (drm_ctx_t *)data, ctx, sizeof(ctx) );
 307
 308         return 0;
 309 }
 310
 311 int DRM(switchctx)( DRM_IOCTL_ARGS )
 312 {
 313         DRM_DEVICE;
 314         drm_ctx_t ctx;
 315
 316         DRM_COPY_FROM_USER_IOCTL( ctx, (drm_ctx_t *)data, sizeof(ctx) );
 317
 318         DRM_DEBUG( "%d\n", ctx.handle );
 319         return DRM(context_switch)( dev, dev->last_context, ctx.handle );
 320 }
 321
 322 int DRM(newctx)( DRM_IOCTL_ARGS )
 323 {
 324         DRM_DEVICE;
 325         drm_ctx_t ctx;
 326
 327         DRM_COPY_FROM_USER_IOCTL( ctx, (drm_ctx_t *)data, sizeof(ctx) );
 328
 329         DRM_DEBUG( "%d\n", ctx.handle );
 330         DRM(context_switch_complete)( dev, ctx.handle );
 331
 332         return 0;
 333 }
 334
 335 int DRM(rmctx)( DRM_IOCTL_ARGS )
 336 {
 337         DRM_DEVICE;
 338         drm_ctx_t ctx;
 339
 340         DRM_COPY_FROM_USER_IOCTL( ctx, (drm_ctx_t *)data, sizeof(ctx) );
 341
 342         DRM_DEBUG( "%d\n", ctx.handle );
 343         if ( ctx.handle != DRM_KERNEL_CONTEXT ) {
 344                 DRM(ctxbitmap_free)( dev, ctx.handle );
 345         }
 346
 347         return 0;
 348 }