drivers/char/drm/radeon_mem.c

   1 /* radeon_mem.c -- Simple GART/fb memory manager for radeon -*- linux-c -*-
   2  *
   3  * Copyright (C) The Weather Channel, Inc.  2002.  All Rights Reserved.
   4  *
   5  * The Weather Channel (TM) funded Tungsten Graphics to develop the
   6  * initial release of the Radeon 8500 driver under the XFree86 license.
   7  * This notice must be preserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice (including the next
  17  * paragraph) shall be included in all copies or substantial portions of the
  18  * Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  23  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  24  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  25  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  26  * DEALINGS IN THE SOFTWARE.
  27  *
  28  * Authors:
  29  *    Keith Whitwell <keith@tungstengraphics.com>
  30  */
  31
  32 #include "drmP.h"
  33 #include "drm.h"
  34 #include "radeon_drm.h"
  35 #include "radeon_drv.h"
  36
  37 /* Very simple allocator for GART memory, working on a static range
  38  * already mapped into each client's address space.
  39  */
  40
  41 static struct mem_block *split_block(struct mem_block *p, int start, int size,
  42                                      DRMFILE filp)
  43 {
  44         /* Maybe cut off the start of an existing block */
  45         if (start > p->start) {
  46                 struct mem_block *newblock =
  47                     drm_alloc(sizeof(*newblock), DRM_MEM_BUFS);
  48                 if (!newblock)
  49                         goto out;
  50                 newblock->start = start;
  51                 newblock->size = p->size - (start - p->start);
  52                 newblock->filp = NULL;
  53                 newblock->next = p->next;
  54                 newblock->prev = p;
  55                 p->next->prev = newblock;
  56                 p->next = newblock;
  57                 p->size -= newblock->size;
  58                 p = newblock;
  59         }
  60
  61         /* Maybe cut off the end of an existing block */
  62         if (size < p->size) {
  63                 struct mem_block *newblock =
  64                     drm_alloc(sizeof(*newblock), DRM_MEM_BUFS);
  65                 if (!newblock)
  66                         goto out;
  67                 newblock->start = start + size;
  68                 newblock->size = p->size - size;
  69                 newblock->filp = NULL;
  70                 newblock->next = p->next;
  71                 newblock->prev = p;
  72                 p->next->prev = newblock;
  73                 p->next = newblock;
  74                 p->size = size;
  75         }
  76
  77       out:
  78         /* Our block is in the middle */
  79         p->filp = filp;
  80         return p;
  81 }
  82
  83 static struct mem_block *alloc_block(struct mem_block *heap, int size,
  84                                      int align2, DRMFILE filp)
  85 {
  86         struct mem_block *p;
  87         int mask = (1 << align2) - 1;
  88
  89         list_for_each(p, heap) {
  90                 int start = (p->start + mask) & ~mask;
  91                 if (p->filp == 0 && start + size <= p->start + p->size)
  92                         return split_block(p, start, size, filp);
  93         }
  94
  95         return NULL;
  96 }
  97
  98 static struct mem_block *find_block(struct mem_block *heap, int start)
  99 {
 100         struct mem_block *p;
 101
 102         list_for_each(p, heap)
 103             if (p->start == start)
 104                 return p;
 105
 106         return NULL;
 107 }
 108
 109 static void free_block(struct mem_block *p)
 110 {
 111         p->filp = NULL;
 112
 113         /* Assumes a single contiguous range.  Needs a special filp in
 114          * 'heap' to stop it being subsumed.
 115          */
 116         if (p->next->filp == 0) {
 117                 struct mem_block *q = p->next;
 118                 p->size += q->size;
 119                 p->next = q->next;
 120                 p->next->prev = p;
 121                 drm_free(q, sizeof(*q), DRM_MEM_BUFS);
 122         }
 123
 124         if (p->prev->filp == 0) {
 125                 struct mem_block *q = p->prev;
 126                 q->size += p->size;
 127                 q->next = p->next;
 128                 q->next->prev = q;
 129                 drm_free(p, sizeof(*q), DRM_MEM_BUFS);
 130         }
 131 }
 132
 133 /* Initialize.  How to check for an uninitialized heap?
 134  */
 135 static int init_heap(struct mem_block **heap, int start, int size)
 136 {
 137         struct mem_block *blocks = drm_alloc(sizeof(*blocks), DRM_MEM_BUFS);
 138
 139         if (!blocks)
 140                 return DRM_ERR(ENOMEM);
 141
 142         *heap = drm_alloc(sizeof(**heap), DRM_MEM_BUFS);
 143         if (!*heap) {
 144                 drm_free(blocks, sizeof(*blocks), DRM_MEM_BUFS);
 145                 return DRM_ERR(ENOMEM);
 146         }
 147
 148         blocks->start = start;
 149         blocks->size = size;
 150         blocks->filp = NULL;
 151         blocks->next = blocks->prev = *heap;
 152
 153         memset(*heap, 0, sizeof(**heap));
 154         (*heap)->filp = (DRMFILE) - 1;
 155         (*heap)->next = (*heap)->prev = blocks;
 156         return 0;
 157 }
 158
 159 /* Free all blocks associated with the releasing file.
 160  */
 161 void radeon_mem_release(DRMFILE filp, struct mem_block *heap)
 162 {
 163         struct mem_block *p;
 164
 165         if (!heap || !heap->next)
 166                 return;
 167
 168         list_for_each(p, heap) {
 169                 if (p->filp == filp)
 170                         p->filp = NULL;
 171         }
 172
 173         /* Assumes a single contiguous range.  Needs a special filp in
 174          * 'heap' to stop it being subsumed.
 175          */
 176         list_for_each(p, heap) {
 177                 while (p->filp == 0 && p->next->filp == 0) {
 178                         struct mem_block *q = p->next;
 179                         p->size += q->size;
 180                         p->next = q->next;
 181                         p->next->prev = p;
 182                         drm_free(q, sizeof(*q), DRM_MEM_DRIVER);
 183                 }
 184         }
 185 }
 186
 187 /* Shutdown.
 188  */
 189 void radeon_mem_takedown(struct mem_block **heap)
 190 {
 191         struct mem_block *p;
 192
 193         if (!*heap)
 194                 return;
 195
 196         for (p = (*heap)->next; p != *heap;) {
 197                 struct mem_block *q = p;
 198                 p = p->next;
 199                 drm_free(q, sizeof(*q), DRM_MEM_DRIVER);
 200         }
 201
 202         drm_free(*heap, sizeof(**heap), DRM_MEM_DRIVER);
 203         *heap = NULL;
 204 }
 205
 206 /* IOCTL HANDLERS */
 207
 208 static struct mem_block **get_heap(drm_radeon_private_t * dev_priv, int region)
 209 {
 210         switch (region) {
 211         case RADEON_MEM_REGION_GART:
 212                 return &dev_priv->gart_heap;
 213         case RADEON_MEM_REGION_FB:
 214                 return &dev_priv->fb_heap;
 215         default:
 216                 return NULL;
 217         }
 218 }
 219
 220 int radeon_mem_alloc(DRM_IOCTL_ARGS)
 221 {
 222         DRM_DEVICE;
 223         drm_radeon_private_t *dev_priv = dev->dev_private;
 224         drm_radeon_mem_alloc_t alloc;
 225         struct mem_block *block, **heap;
 226
 227         if (!dev_priv) {
 228                 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 229                 return DRM_ERR(EINVAL);
 230         }
 231
 232         DRM_COPY_FROM_USER_IOCTL(alloc, (drm_radeon_mem_alloc_t __user *) data,
 233                                  sizeof(alloc));
 234
 235         heap = get_heap(dev_priv, alloc.region);
 236         if (!heap || !*heap)
 237                 return DRM_ERR(EFAULT);
 238
 239         /* Make things easier on ourselves: all allocations at least
 240          * 4k aligned.
 241          */
 242         if (alloc.alignment < 12)
 243                 alloc.alignment = 12;
 244
 245         block = alloc_block(*heap, alloc.size, alloc.alignment, filp);
 246
 247         if (!block)
 248                 return DRM_ERR(ENOMEM);
 249
 250         if (DRM_COPY_TO_USER(alloc.region_offset, &block->start, sizeof(int))) {
 251                 DRM_ERROR("copy_to_user\n");
 252                 return DRM_ERR(EFAULT);
 253         }
 254
 255         return 0;
 256 }
 257
 258 int radeon_mem_free(DRM_IOCTL_ARGS)
 259 {
 260         DRM_DEVICE;
 261         drm_radeon_private_t *dev_priv = dev->dev_private;
 262         drm_radeon_mem_free_t memfree;
 263         struct mem_block *block, **heap;
 264
 265         if (!dev_priv) {
 266                 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 267                 return DRM_ERR(EINVAL);
 268         }
 269
 270         DRM_COPY_FROM_USER_IOCTL(memfree, (drm_radeon_mem_free_t __user *) data,
 271                                  sizeof(memfree));
 272
 273         heap = get_heap(dev_priv, memfree.region);
 274         if (!heap || !*heap)
 275                 return DRM_ERR(EFAULT);
 276
 277         block = find_block(*heap, memfree.region_offset);
 278         if (!block)
 279                 return DRM_ERR(EFAULT);
 280
 281         if (block->filp != filp)
 282                 return DRM_ERR(EPERM);
 283
 284         free_block(block);
 285         return 0;
 286 }
 287
 288 int radeon_mem_init_heap(DRM_IOCTL_ARGS)
 289 {
 290         DRM_DEVICE;
 291         drm_radeon_private_t *dev_priv = dev->dev_private;
 292         drm_radeon_mem_init_heap_t initheap;
 293         struct mem_block **heap;
 294
 295         if (!dev_priv) {
 296                 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 297                 return DRM_ERR(EINVAL);
 298         }
 299
 300         DRM_COPY_FROM_USER_IOCTL(initheap,
 301                                  (drm_radeon_mem_init_heap_t __user *) data,
 302                                  sizeof(initheap));
 303
 304         heap = get_heap(dev_priv, initheap.region);
 305         if (!heap)
 306                 return DRM_ERR(EFAULT);
 307
 308         if (*heap) {
 309                 DRM_ERROR("heap already initialized?");
 310                 return DRM_ERR(EFAULT);
 311         }
 312
 313         return init_heap(heap, initheap.start, initheap.size);
 314 }