linux-core/drm_ttm.c

   1 /**************************************************************************
   2  *
   3  * Copyright (c) 2006-2007 Tungsten Graphics, Inc., Cedar Park, TX., USA
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27 /*
  28  * Authors: Thomas Hellström <thomas-at-tungstengraphics-dot-com>
  29  */
  30
  31 #include "drmP.h"
  32
  33 static void drm_ttm_ipi_handler(void *null)
  34 {
  35         flush_agp_cache();
  36 }
  37
  38 static void drm_ttm_cache_flush(void)
  39 {
  40         if (on_each_cpu(drm_ttm_ipi_handler, NULL, 1, 1) != 0)
  41                 DRM_ERROR("Timed out waiting for drm cache flush.\n");
  42 }
  43
  44 /*
  45  * Use kmalloc if possible. Otherwise fall back to vmalloc.
  46  */
  47
  48 static void ttm_alloc_pages(drm_ttm_t * ttm)
  49 {
  50         unsigned long size = ttm->num_pages * sizeof(*ttm->pages);
  51         ttm->pages = NULL;
  52
  53         if (drm_alloc_memctl(size))
  54                 return;
  55
  56         if (size <= PAGE_SIZE) {
  57                 ttm->pages = drm_calloc(1, size, DRM_MEM_TTM);
  58         }
  59         if (!ttm->pages) {
  60                 ttm->pages = vmalloc_user(size);
  61                 if (ttm->pages)
  62                         ttm->page_flags |= DRM_TTM_PAGE_VMALLOC;
  63         }
  64         if (!ttm->pages) {
  65                 drm_free_memctl(size);
  66         }
  67 }
  68
  69 static void ttm_free_pages(drm_ttm_t * ttm)
  70 {
  71         unsigned long size = ttm->num_pages * sizeof(*ttm->pages);
  72
  73         if (ttm->page_flags & DRM_TTM_PAGE_VMALLOC) {
  74                 vfree(ttm->pages);
  75                 ttm->page_flags &= ~DRM_TTM_PAGE_VMALLOC;
  76         } else {
  77                 drm_free(ttm->pages, size, DRM_MEM_TTM);
  78         }
  79         drm_free_memctl(size);
  80         ttm->pages = NULL;
  81 }
  82
  83 static struct page *drm_ttm_alloc_page(void)
  84 {
  85         struct page *page;
  86
  87         if (drm_alloc_memctl(PAGE_SIZE)) {
  88                 return NULL;
  89         }
  90         page = alloc_page(GFP_KERNEL | __GFP_ZERO | GFP_DMA32);
  91         if (!page) {
  92                 drm_free_memctl(PAGE_SIZE);
  93                 return NULL;
  94         }
  95 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,15))
  96         SetPageLocked(page);
  97 #else
  98         SetPageReserved(page);
  99 #endif
 100         return page;
 101 }
 102
 103 /*
 104  * Change caching policy for the linear kernel map
 105  * for range of pages in a ttm.
 106  */
 107
 108 static int drm_set_caching(drm_ttm_t * ttm, int noncached)
 109 {
 110         int i;
 111         struct page **cur_page;
 112         int do_tlbflush = 0;
 113
 114         if ((ttm->page_flags & DRM_TTM_PAGE_UNCACHED) == noncached)
 115                 return 0;
 116
 117         if (noncached)
 118                 drm_ttm_cache_flush();
 119
 120         for (i = 0; i < ttm->num_pages; ++i) {
 121                 cur_page = ttm->pages + i;
 122                 if (*cur_page) {
 123                         if (!PageHighMem(*cur_page)) {
 124                                 if (noncached) {
 125                                         map_page_into_agp(*cur_page);
 126                                 } else {
 127                                         unmap_page_from_agp(*cur_page);
 128                                 }
 129                                 do_tlbflush = 1;
 130                         }
 131                 }
 132         }
 133         if (do_tlbflush)
 134                 flush_agp_mappings();
 135
 136         DRM_FLAG_MASKED(ttm->page_flags, noncached, DRM_TTM_PAGE_UNCACHED);
 137
 138         return 0;
 139 }
 140
 141 /*
 142  * Free all resources associated with a ttm.
 143  */
 144
 145 int drm_destroy_ttm(drm_ttm_t * ttm)
 146 {
 147
 148         int i;
 149         struct page **cur_page;
 150         drm_ttm_backend_t *be;
 151
 152         if (!ttm)
 153                 return 0;
 154
 155         be = ttm->be;
 156         if (be) {
 157                 be->func->destroy(be);
 158                 ttm->be = NULL;
 159         }
 160
 161         if (ttm->pages) {
 162                 drm_buffer_manager_t *bm = &ttm->dev->bm;
 163                 if (ttm->page_flags & DRM_TTM_PAGE_UNCACHED)
 164                         drm_set_caching(ttm, 0);
 165
 166                 for (i = 0; i < ttm->num_pages; ++i) {
 167                         cur_page = ttm->pages + i;
 168                         if (*cur_page) {
 169 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,15))
 170                                 unlock_page(*cur_page);
 171 #else
 172                                 ClearPageReserved(*cur_page);
 173 #endif
 174                                 if (page_count(*cur_page) != 1) {
 175                                         DRM_ERROR("Erroneous page count. "
 176                                                   "Leaking pages.\n");
 177                                 }
 178                                 if (page_mapped(*cur_page)) {
 179                                         DRM_ERROR("Erroneous map count. "
 180                                                   "Leaking page mappings.\n");
 181                                 }
 182                                 __free_page(*cur_page);
 183                                 drm_free_memctl(PAGE_SIZE);
 184                                 --bm->cur_pages;
 185                         }
 186                 }
 187                 ttm_free_pages(ttm);
 188         }
 189
 190         drm_ctl_free(ttm, sizeof(*ttm), DRM_MEM_TTM);
 191         return 0;
 192 }
 193
 194 struct page *drm_ttm_get_page(drm_ttm_t * ttm, int index)
 195 {
 196         struct page *p;
 197         drm_buffer_manager_t *bm = &ttm->dev->bm;
 198
 199         p = ttm->pages[index];
 200         if (!p) {
 201                 p = drm_ttm_alloc_page();
 202                 if (!p)
 203                         return NULL;
 204                 ttm->pages[index] = p;
 205                 ++bm->cur_pages;
 206         }
 207         return p;
 208 }
 209
 210 static int drm_ttm_populate(drm_ttm_t * ttm)
 211 {
 212         struct page *page;
 213         unsigned long i;
 214         drm_ttm_backend_t *be;
 215
 216         if (ttm->state != ttm_unpopulated)
 217                 return 0;
 218
 219         be = ttm->be;
 220         for (i = 0; i < ttm->num_pages; ++i) {
 221                 page = drm_ttm_get_page(ttm, i);
 222                 if (!page)
 223                         return -ENOMEM;
 224         }
 225         be->func->populate(be, ttm->num_pages, ttm->pages);
 226         ttm->state = ttm_unbound;
 227         return 0;
 228 }
 229
 230 /*
 231  * Initialize a ttm.
 232  */
 233
 234 drm_ttm_t *drm_ttm_init(struct drm_device * dev, unsigned long size)
 235 {
 236         drm_bo_driver_t *bo_driver = dev->driver->bo_driver;
 237         drm_ttm_t *ttm;
 238
 239         if (!bo_driver)
 240                 return NULL;
 241
 242         ttm = drm_ctl_calloc(1, sizeof(*ttm), DRM_MEM_TTM);
 243         if (!ttm)
 244                 return NULL;
 245
 246         ttm->dev = dev;
 247         atomic_set(&ttm->vma_count, 0);
 248
 249         ttm->destroy = 0;
 250         ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
 251
 252         ttm->page_flags = 0;
 253
 254         /*
 255          * Account also for AGP module memory usage.
 256          */
 257
 258         ttm_alloc_pages(ttm);
 259         if (!ttm->pages) {
 260                 drm_destroy_ttm(ttm);
 261                 DRM_ERROR("Failed allocating page table\n");
 262                 return NULL;
 263         }
 264         ttm->be = bo_driver->create_ttm_backend_entry(dev);
 265         if (!ttm->be) {
 266                 drm_destroy_ttm(ttm);
 267                 DRM_ERROR("Failed creating ttm backend entry\n");
 268                 return NULL;
 269         }
 270         ttm->state = ttm_unpopulated;
 271         return ttm;
 272 }
 273
 274 /*
 275  * Unbind a ttm region from the aperture.
 276  */
 277
 278 void drm_ttm_evict(drm_ttm_t * ttm)
 279 {
 280         drm_ttm_backend_t *be = ttm->be;
 281         int ret;
 282
 283         if (ttm->state == ttm_bound) {
 284                 ret = be->func->unbind(be);
 285                 BUG_ON(ret);
 286         }
 287
 288         ttm->state = ttm_evicted;
 289 }
 290
 291 void drm_ttm_fixup_caching(drm_ttm_t * ttm)
 292 {
 293
 294         if (ttm->state == ttm_evicted) {
 295                 drm_ttm_backend_t *be = ttm->be;
 296                 if (be->func->needs_ub_cache_adjust(be)) {
 297                         drm_set_caching(ttm, 0);
 298                 }
 299                 ttm->state = ttm_unbound;
 300         }
 301 }
 302
 303 void drm_ttm_unbind(drm_ttm_t * ttm)
 304 {
 305         if (ttm->state == ttm_bound)
 306                 drm_ttm_evict(ttm);
 307
 308         drm_ttm_fixup_caching(ttm);
 309 }
 310
 311 int drm_bind_ttm(drm_ttm_t * ttm, int cached, unsigned long aper_offset)
 312 {
 313
 314         int ret = 0;
 315         drm_ttm_backend_t *be;
 316
 317         if (!ttm)
 318                 return -EINVAL;
 319         if (ttm->state == ttm_bound)
 320                 return 0;
 321
 322         be = ttm->be;
 323
 324         ret = drm_ttm_populate(ttm);
 325         if (ret)
 326                 return ret;
 327
 328         if (ttm->state == ttm_unbound && !cached) {
 329                 drm_set_caching(ttm, DRM_TTM_PAGE_UNCACHED);
 330         }
 331
 332         if ((ret = be->func->bind(be, aper_offset, cached))) {
 333                 ttm->state = ttm_evicted;
 334                 DRM_ERROR("Couldn't bind backend.\n");
 335                 return ret;
 336         }
 337
 338         ttm->aper_offset = aper_offset;
 339         ttm->state = ttm_bound;
 340
 341         return 0;
 342 }
 343
 344 EXPORT_SYMBOL(drm_bind_ttm);