drivers/gpu/drm/i915/i915_mem.c

   1 /* i915_mem.c -- Simple agp/fb memory manager for i915 -*- linux-c -*-
   2  */
   3 /*
   4  * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
   5  * All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the
   9  * "Software"), to deal in the Software without restriction, including
  10  * without limitation the rights to use, copy, modify, merge, publish,
  11  * distribute, sub license, and/or sell copies of the Software, and to
  12  * permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the
  16  * next paragraph) shall be included in all copies or substantial portions
  17  * of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  22  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  23  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  24  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  25  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  26  *
  27  */
  28
  29 #include "drmP.h"
  30 #include "drm.h"
  31 #include "i915_drm.h"
  32 #include "i915_drv.h"
  33
  34 /* This memory manager is integrated into the global/local lru
  35  * mechanisms used by the clients.  Specifically, it operates by
  36  * setting the 'in_use' fields of the global LRU to indicate whether
  37  * this region is privately allocated to a client.
  38  *
  39  * This does require the client to actually respect that field.
  40  *
  41  * Currently no effort is made to allocate 'private' memory in any
  42  * clever way - the LRU information isn't used to determine which
  43  * block to allocate, and the ring is drained prior to allocations --
  44  * in other words allocation is expensive.
  45  */
  46 static void mark_block(struct drm_device * dev, struct mem_block *p, int in_use)
  47 {
  48         drm_i915_private_t *dev_priv = dev->dev_private;
  49         struct drm_i915_master_private *master_priv = dev->primary->master->driver_priv;
  50         drm_i915_sarea_t *sarea_priv = master_priv->sarea_priv;
  51         struct drm_tex_region *list;
  52         unsigned shift, nr;
  53         unsigned start;
  54         unsigned end;
  55         unsigned i;
  56         int age;
  57
  58         shift = dev_priv->tex_lru_log_granularity;
  59         nr = I915_NR_TEX_REGIONS;
  60
  61         start = p->start >> shift;
  62         end = (p->start + p->size - 1) >> shift;
  63
  64         age = ++sarea_priv->texAge;
  65         list = sarea_priv->texList;
  66
  67         /* Mark the regions with the new flag and update their age.  Move
  68          * them to head of list to preserve LRU semantics.
  69          */
  70         for (i = start; i <= end; i++) {
  71                 list[i].in_use = in_use;
  72                 list[i].age = age;
  73
  74                 /* remove_from_list(i)
  75                  */
  76                 list[(unsigned)list[i].next].prev = list[i].prev;
  77                 list[(unsigned)list[i].prev].next = list[i].next;
  78
  79                 /* insert_at_head(list, i)
  80                  */
  81                 list[i].prev = nr;
  82                 list[i].next = list[nr].next;
  83                 list[(unsigned)list[nr].next].prev = i;
  84                 list[nr].next = i;
  85         }
  86 }
  87
  88 /* Very simple allocator for agp memory, working on a static range
  89  * already mapped into each client's address space.
  90  */
  91
  92 static struct mem_block *split_block(struct mem_block *p, int start, int size,
  93                                      struct drm_file *file_priv)
  94 {
  95         /* Maybe cut off the start of an existing block */
  96         if (start > p->start) {
  97                 struct mem_block *newblock = kmalloc(sizeof(*newblock),
  98                                                      GFP_KERNEL);
  99                 if (!newblock)
 100                         goto out;
 101                 newblock->start = start;
 102                 newblock->size = p->size - (start - p->start);
 103                 newblock->file_priv = NULL;
 104                 newblock->next = p->next;
 105                 newblock->prev = p;
 106                 p->next->prev = newblock;
 107                 p->next = newblock;
 108                 p->size -= newblock->size;
 109                 p = newblock;
 110         }
 111
 112         /* Maybe cut off the end of an existing block */
 113         if (size < p->size) {
 114                 struct mem_block *newblock = kmalloc(sizeof(*newblock),
 115                                                      GFP_KERNEL);
 116                 if (!newblock)
 117                         goto out;
 118                 newblock->start = start + size;
 119                 newblock->size = p->size - size;
 120                 newblock->file_priv = NULL;
 121                 newblock->next = p->next;
 122                 newblock->prev = p;
 123                 p->next->prev = newblock;
 124                 p->next = newblock;
 125                 p->size = size;
 126         }
 127
 128       out:
 129         /* Our block is in the middle */
 130         p->file_priv = file_priv;
 131         return p;
 132 }
 133
 134 static struct mem_block *alloc_block(struct mem_block *heap, int size,
 135                                      int align2, struct drm_file *file_priv)
 136 {
 137         struct mem_block *p;
 138         int mask = (1 << align2) - 1;
 139
 140         for (p = heap->next; p != heap; p = p->next) {
 141                 int start = (p->start + mask) & ~mask;
 142                 if (p->file_priv == NULL && start + size <= p->start + p->size)
 143                         return split_block(p, start, size, file_priv);
 144         }
 145
 146         return NULL;
 147 }
 148
 149 static struct mem_block *find_block(struct mem_block *heap, int start)
 150 {
 151         struct mem_block *p;
 152
 153         for (p = heap->next; p != heap; p = p->next)
 154                 if (p->start == start)
 155                         return p;
 156
 157         return NULL;
 158 }
 159
 160 static void free_block(struct mem_block *p)
 161 {
 162         p->file_priv = NULL;
 163
 164         /* Assumes a single contiguous range.  Needs a special file_priv in
 165          * 'heap' to stop it being subsumed.
 166          */
 167         if (p->next->file_priv == NULL) {
 168                 struct mem_block *q = p->next;
 169                 p->size += q->size;
 170                 p->next = q->next;
 171                 p->next->prev = p;
 172                 kfree(q);
 173         }
 174
 175         if (p->prev->file_priv == NULL) {
 176                 struct mem_block *q = p->prev;
 177                 q->size += p->size;
 178                 q->next = p->next;
 179                 q->next->prev = q;
 180                 kfree(p);
 181         }
 182 }
 183
 184 /* Initialize.  How to check for an uninitialized heap?
 185  */
 186 static int init_heap(struct mem_block **heap, int start, int size)
 187 {
 188         struct mem_block *blocks = kmalloc(sizeof(*blocks), GFP_KERNEL);
 189
 190         if (!blocks)
 191                 return -ENOMEM;
 192
 193         *heap = kmalloc(sizeof(**heap), GFP_KERNEL);
 194         if (!*heap) {
 195                 kfree(blocks);
 196                 return -ENOMEM;
 197         }
 198
 199         blocks->start = start;
 200         blocks->size = size;
 201         blocks->file_priv = NULL;
 202         blocks->next = blocks->prev = *heap;
 203
 204         memset(*heap, 0, sizeof(**heap));
 205         (*heap)->file_priv = (struct drm_file *) -1;
 206         (*heap)->next = (*heap)->prev = blocks;
 207         return 0;
 208 }
 209
 210 /* Free all blocks associated with the releasing file.
 211  */
 212 void i915_mem_release(struct drm_device * dev, struct drm_file *file_priv,
 213                       struct mem_block *heap)
 214 {
 215         struct mem_block *p;
 216
 217         if (!heap || !heap->next)
 218                 return;
 219
 220         for (p = heap->next; p != heap; p = p->next) {
 221                 if (p->file_priv == file_priv) {
 222                         p->file_priv = NULL;
 223                         mark_block(dev, p, 0);
 224                 }
 225         }
 226
 227         /* Assumes a single contiguous range.  Needs a special file_priv in
 228          * 'heap' to stop it being subsumed.
 229          */
 230         for (p = heap->next; p != heap; p = p->next) {
 231                 while (p->file_priv == NULL && p->next->file_priv == NULL) {
 232                         struct mem_block *q = p->next;
 233                         p->size += q->size;
 234                         p->next = q->next;
 235                         p->next->prev = p;
 236                         kfree(q);
 237                 }
 238         }
 239 }
 240
 241 /* Shutdown.
 242  */
 243 void i915_mem_takedown(struct mem_block **heap)
 244 {
 245         struct mem_block *p;
 246
 247         if (!*heap)
 248                 return;
 249
 250         for (p = (*heap)->next; p != *heap;) {
 251                 struct mem_block *q = p;
 252                 p = p->next;
 253                 kfree(q);
 254         }
 255
 256         kfree(*heap);
 257         *heap = NULL;
 258 }
 259
 260 static struct mem_block **get_heap(drm_i915_private_t * dev_priv, int region)
 261 {
 262         switch (region) {
 263         case I915_MEM_REGION_AGP:
 264                 return &dev_priv->agp_heap;
 265         default:
 266                 return NULL;
 267         }
 268 }
 269
 270 /* IOCTL HANDLERS */
 271
 272 int i915_mem_alloc(struct drm_device *dev, void *data,
 273                    struct drm_file *file_priv)
 274 {
 275         drm_i915_private_t *dev_priv = dev->dev_private;
 276         drm_i915_mem_alloc_t *alloc = data;
 277         struct mem_block *block, **heap;
 278
 279         if (!dev_priv) {
 280                 DRM_ERROR("called with no initialization\n");
 281                 return -EINVAL;
 282         }
 283
 284         heap = get_heap(dev_priv, alloc->region);
 285         if (!heap || !*heap)
 286                 return -EFAULT;
 287
 288         /* Make things easier on ourselves: all allocations at least
 289          * 4k aligned.
 290          */
 291         if (alloc->alignment < 12)
 292                 alloc->alignment = 12;
 293
 294         block = alloc_block(*heap, alloc->size, alloc->alignment, file_priv);
 295
 296         if (!block)
 297                 return -ENOMEM;
 298
 299         mark_block(dev, block, 1);
 300
 301         if (DRM_COPY_TO_USER(alloc->region_offset, &block->start,
 302                              sizeof(int))) {
 303                 DRM_ERROR("copy_to_user\n");
 304                 return -EFAULT;
 305         }
 306
 307         return 0;
 308 }
 309
 310 int i915_mem_free(struct drm_device *dev, void *data,
 311                   struct drm_file *file_priv)
 312 {
 313         drm_i915_private_t *dev_priv = dev->dev_private;
 314         drm_i915_mem_free_t *memfree = data;
 315         struct mem_block *block, **heap;
 316
 317         if (!dev_priv) {
 318                 DRM_ERROR("called with no initialization\n");
 319                 return -EINVAL;
 320         }
 321
 322         heap = get_heap(dev_priv, memfree->region);
 323         if (!heap || !*heap)
 324                 return -EFAULT;
 325
 326         block = find_block(*heap, memfree->region_offset);
 327         if (!block)
 328                 return -EFAULT;
 329
 330         if (block->file_priv != file_priv)
 331                 return -EPERM;
 332
 333         mark_block(dev, block, 0);
 334         free_block(block);
 335         return 0;
 336 }
 337
 338 int i915_mem_init_heap(struct drm_device *dev, void *data,
 339                        struct drm_file *file_priv)
 340 {
 341         drm_i915_private_t *dev_priv = dev->dev_private;
 342         drm_i915_mem_init_heap_t *initheap = data;
 343         struct mem_block **heap;
 344
 345         if (!dev_priv) {
 346                 DRM_ERROR("called with no initialization\n");
 347                 return -EINVAL;
 348         }
 349
 350         heap = get_heap(dev_priv, initheap->region);
 351         if (!heap)
 352                 return -EFAULT;
 353
 354         if (*heap) {
 355                 DRM_ERROR("heap already initialized?");
 356                 return -EFAULT;
 357         }
 358
 359         return init_heap(heap, initheap->start, initheap->size);
 360 }
 361
 362 int i915_mem_destroy_heap(struct drm_device *dev, void *data,
 363                            struct drm_file *file_priv)
 364 {
 365         drm_i915_private_t *dev_priv = dev->dev_private;
 366         drm_i915_mem_destroy_heap_t *destroyheap = data;
 367         struct mem_block **heap;
 368
 369         if (!dev_priv) {
 370                 DRM_ERROR("called with no initialization\n");
 371                 return -EINVAL;
 372         }
 373
 374         heap = get_heap(dev_priv, destroyheap->region);
 375         if (!heap) {
 376                 DRM_ERROR("get_heap failed");
 377                 return -EFAULT;
 378         }
 379
 380         if (!*heap) {
 381                 DRM_ERROR("heap not initialized?");
 382                 return -EFAULT;
 383         }
 384
 385         i915_mem_takedown(heap);
 386         return 0;
 387 }