drivers/staging/android/ion/ion_system_heap.c

   1 /*
   2  * drivers/staging/android/ion/ion_system_heap.c
   3  *
   4  * Copyright (C) 2011 Google, Inc.
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  */
  16
  17 #include <asm/page.h>
  18 #include <linux/dma-mapping.h>
  19 #include <linux/err.h>
  20 #include <linux/highmem.h>
  21 #include <linux/mm.h>
  22 #include <linux/scatterlist.h>
  23 #include <linux/seq_file.h>
  24 #include <linux/slab.h>
  25 #include <linux/vmalloc.h>
  26 #include "ion.h"
  27 #include "ion_priv.h"
  28
  29 static gfp_t high_order_gfp_flags = (GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN |
  30                                      __GFP_NORETRY) & ~__GFP_WAIT;
  31 static gfp_t low_order_gfp_flags  = (GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN);
  32 static const unsigned int orders[] = {8, 4, 0};
  33 static const int num_orders = ARRAY_SIZE(orders);
  34 static int order_to_index(unsigned int order)
  35 {
  36         int i;
  37         for (i = 0; i < num_orders; i++)
  38                 if (order == orders[i])
  39                         return i;
  40         BUG();
  41         return -1;
  42 }
  43
  44 static unsigned int order_to_size(int order)
  45 {
  46         return PAGE_SIZE << order;
  47 }
  48
  49 struct ion_system_heap {
  50         struct ion_heap heap;
  51         struct ion_page_pool **pools;
  52 };
  53
  54 struct page_info {
  55         struct page *page;
  56         unsigned int order;
  57         struct list_head list;
  58 };
  59
  60 static struct page *alloc_buffer_page(struct ion_system_heap *heap,
  61                                       struct ion_buffer *buffer,
  62                                       unsigned long order)
  63 {
  64         bool cached = ion_buffer_cached(buffer);
  65         struct ion_page_pool *pool = heap->pools[order_to_index(order)];
  66         struct page *page;
  67
  68         if (!cached) {
  69                 page = ion_page_pool_alloc(pool);
  70         } else {
  71                 gfp_t gfp_flags = low_order_gfp_flags;
  72
  73                 if (order > 4)
  74                         gfp_flags = high_order_gfp_flags;
  75                 page = alloc_pages(gfp_flags, order);
  76                 if (!page)
  77                         return NULL;
  78                 ion_pages_sync_for_device(NULL, page, PAGE_SIZE << order,
  79                                                 DMA_BIDIRECTIONAL);
  80         }
  81         if (!page)
  82                 return NULL;
  83
  84         return page;
  85 }
  86
  87 static void free_buffer_page(struct ion_system_heap *heap,
  88                              struct ion_buffer *buffer, struct page *page,
  89                              unsigned int order)
  90 {
  91         bool cached = ion_buffer_cached(buffer);
  92
  93         if (!cached) {
  94                 struct ion_page_pool *pool = heap->pools[order_to_index(order)];
  95                 ion_page_pool_free(pool, page);
  96         } else {
  97                 __free_pages(page, order);
  98         }
  99 }
 100
 101
 102 static struct page_info *alloc_largest_available(struct ion_system_heap *heap,
 103                                                  struct ion_buffer *buffer,
 104                                                  unsigned long size,
 105                                                  unsigned int max_order)
 106 {
 107         struct page *page;
 108         struct page_info *info;
 109         int i;
 110
 111         info = kmalloc(sizeof(struct page_info), GFP_KERNEL);
 112         if (!info)
 113                 return NULL;
 114
 115         for (i = 0; i < num_orders; i++) {
 116                 if (size < order_to_size(orders[i]))
 117                         continue;
 118                 if (max_order < orders[i])
 119                         continue;
 120
 121                 page = alloc_buffer_page(heap, buffer, orders[i]);
 122                 if (!page)
 123                         continue;
 124
 125                 info->page = page;
 126                 info->order = orders[i];
 127                 INIT_LIST_HEAD(&info->list);
 128                 return info;
 129         }
 130         kfree(info);
 131
 132         return NULL;
 133 }
 134
 135 static int ion_system_heap_allocate(struct ion_heap *heap,
 136                                      struct ion_buffer *buffer,
 137                                      unsigned long size, unsigned long align,
 138                                      unsigned long flags)
 139 {
 140         struct ion_system_heap *sys_heap = container_of(heap,
 141                                                         struct ion_system_heap,
 142                                                         heap);
 143         struct sg_table *table;
 144         struct scatterlist *sg;
 145         int ret;
 146         struct list_head pages;
 147         struct page_info *info, *tmp_info;
 148         int i = 0;
 149         unsigned long size_remaining = PAGE_ALIGN(size);
 150         unsigned int max_order = orders[0];
 151
 152         if (align > PAGE_SIZE)
 153                 return -EINVAL;
 154
 155         if (size / PAGE_SIZE > totalram_pages / 2)
 156                 return -ENOMEM;
 157
 158         INIT_LIST_HEAD(&pages);
 159         while (size_remaining > 0) {
 160                 info = alloc_largest_available(sys_heap, buffer, size_remaining,
 161                                                 max_order);
 162                 if (!info)
 163                         goto err;
 164                 list_add_tail(&info->list, &pages);
 165                 size_remaining -= (1 << info->order) * PAGE_SIZE;
 166                 max_order = info->order;
 167                 i++;
 168         }
 169         table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
 170         if (!table)
 171                 goto err;
 172
 173         ret = sg_alloc_table(table, i, GFP_KERNEL);
 174         if (ret)
 175                 goto err1;
 176
 177         sg = table->sgl;
 178         list_for_each_entry_safe(info, tmp_info, &pages, list) {
 179                 struct page *page = info->page;
 180                 sg_set_page(sg, page, (1 << info->order) * PAGE_SIZE, 0);
 181                 sg = sg_next(sg);
 182                 list_del(&info->list);
 183                 kfree(info);
 184         }
 185
 186         buffer->priv_virt = table;
 187         return 0;
 188 err1:
 189         kfree(table);
 190 err:
 191         list_for_each_entry_safe(info, tmp_info, &pages, list) {
 192                 free_buffer_page(sys_heap, buffer, info->page, info->order);
 193                 kfree(info);
 194         }
 195         return -ENOMEM;
 196 }
 197
 198 static void ion_system_heap_free(struct ion_buffer *buffer)
 199 {
 200         struct ion_heap *heap = buffer->heap;
 201         struct ion_system_heap *sys_heap = container_of(heap,
 202                                                         struct ion_system_heap,
 203                                                         heap);
 204         struct sg_table *table = buffer->sg_table;
 205         bool cached = ion_buffer_cached(buffer);
 206         struct scatterlist *sg;
 207         LIST_HEAD(pages);
 208         int i;
 209
 210         /* uncached pages come from the page pools, zero them before returning
 211            for security purposes (other allocations are zerod at alloc time */
 212         if (!cached)
 213                 ion_heap_buffer_zero(buffer);
 214
 215         for_each_sg(table->sgl, sg, table->nents, i)
 216                 free_buffer_page(sys_heap, buffer, sg_page(sg),
 217                                 get_order(sg->length));
 218         sg_free_table(table);
 219         kfree(table);
 220 }
 221
 222 static struct sg_table *ion_system_heap_map_dma(struct ion_heap *heap,
 223                                                 struct ion_buffer *buffer)
 224 {
 225         return buffer->priv_virt;
 226 }
 227
 228 static void ion_system_heap_unmap_dma(struct ion_heap *heap,
 229                                       struct ion_buffer *buffer)
 230 {
 231         return;
 232 }
 233
 234 static struct ion_heap_ops system_heap_ops = {
 235         .allocate = ion_system_heap_allocate,
 236         .free = ion_system_heap_free,
 237         .map_dma = ion_system_heap_map_dma,
 238         .unmap_dma = ion_system_heap_unmap_dma,
 239         .map_kernel = ion_heap_map_kernel,
 240         .unmap_kernel = ion_heap_unmap_kernel,
 241         .map_user = ion_heap_map_user,
 242 };
 243
 244 static unsigned long ion_system_heap_shrink_count(struct shrinker *shrinker,
 245                                   struct shrink_control *sc)
 246 {
 247         struct ion_heap *heap = container_of(shrinker, struct ion_heap,
 248                                              shrinker);
 249         struct ion_system_heap *sys_heap = container_of(heap,
 250                                                         struct ion_system_heap,
 251                                                         heap);
 252         int nr_total = 0;
 253         int i;
 254
 255         /* total number of items is whatever the page pools are holding
 256            plus whatever's in the freelist */
 257         for (i = 0; i < num_orders; i++) {
 258                 struct ion_page_pool *pool = sys_heap->pools[i];
 259                 nr_total += ion_page_pool_shrink(pool, sc->gfp_mask, 0);
 260         }
 261         nr_total += ion_heap_freelist_size(heap) / PAGE_SIZE;
 262         return nr_total;
 263
 264 }
 265
 266 static unsigned long ion_system_heap_shrink_scan(struct shrinker *shrinker,
 267                                   struct shrink_control *sc)
 268 {
 269
 270         struct ion_heap *heap = container_of(shrinker, struct ion_heap,
 271                                              shrinker);
 272         struct ion_system_heap *sys_heap = container_of(heap,
 273                                                         struct ion_system_heap,
 274                                                         heap);
 275         int nr_freed = 0;
 276         int i;
 277
 278         if (sc->nr_to_scan == 0)
 279                 goto end;
 280
 281         /* shrink the free list first, no point in zeroing the memory if
 282            we're just going to reclaim it */
 283         nr_freed += ion_heap_freelist_drain(heap, sc->nr_to_scan * PAGE_SIZE) /
 284                 PAGE_SIZE;
 285
 286         if (nr_freed >= sc->nr_to_scan)
 287                 goto end;
 288
 289         for (i = 0; i < num_orders; i++) {
 290                 struct ion_page_pool *pool = sys_heap->pools[i];
 291
 292                 nr_freed += ion_page_pool_shrink(pool, sc->gfp_mask,
 293                                                  sc->nr_to_scan);
 294                 if (nr_freed >= sc->nr_to_scan)
 295                         break;
 296         }
 297
 298 end:
 299         return nr_freed;
 300
 301 }
 302
 303 static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
 304                                       void *unused)
 305 {
 306
 307         struct ion_system_heap *sys_heap = container_of(heap,
 308                                                         struct ion_system_heap,
 309                                                         heap);
 310         int i;
 311         for (i = 0; i < num_orders; i++) {
 312                 struct ion_page_pool *pool = sys_heap->pools[i];
 313                 seq_printf(s, "%d order %u highmem pages in pool = %lu total\n",
 314                            pool->high_count, pool->order,
 315                            (1 << pool->order) * PAGE_SIZE * pool->high_count);
 316                 seq_printf(s, "%d order %u lowmem pages in pool = %lu total\n",
 317                            pool->low_count, pool->order,
 318                            (1 << pool->order) * PAGE_SIZE * pool->low_count);
 319         }
 320         return 0;
 321 }
 322
 323 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
 324 {
 325         struct ion_system_heap *heap;
 326         int i;
 327
 328         heap = kzalloc(sizeof(struct ion_system_heap), GFP_KERNEL);
 329         if (!heap)
 330                 return ERR_PTR(-ENOMEM);
 331         heap->heap.ops = &system_heap_ops;
 332         heap->heap.type = ION_HEAP_TYPE_SYSTEM;
 333         heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
 334         heap->pools = kzalloc(sizeof(struct ion_page_pool *) * num_orders,
 335                               GFP_KERNEL);
 336         if (!heap->pools)
 337                 goto err_alloc_pools;
 338         for (i = 0; i < num_orders; i++) {
 339                 struct ion_page_pool *pool;
 340                 gfp_t gfp_flags = low_order_gfp_flags;
 341
 342                 if (orders[i] > 4)
 343                         gfp_flags = high_order_gfp_flags;
 344                 pool = ion_page_pool_create(gfp_flags, orders[i]);
 345                 if (!pool)
 346                         goto err_create_pool;
 347                 heap->pools[i] = pool;
 348         }
 349
 350         heap->heap.shrinker.scan_objects = ion_system_heap_shrink_scan;
 351         heap->heap.shrinker.count_objects = ion_system_heap_shrink_count;
 352         heap->heap.shrinker.seeks = DEFAULT_SEEKS;
 353         heap->heap.shrinker.batch = 0;
 354         register_shrinker(&heap->heap.shrinker);
 355         heap->heap.debug_show = ion_system_heap_debug_show;
 356         return &heap->heap;
 357 err_create_pool:
 358         for (i = 0; i < num_orders; i++)
 359                 if (heap->pools[i])
 360                         ion_page_pool_destroy(heap->pools[i]);
 361         kfree(heap->pools);
 362 err_alloc_pools:
 363         kfree(heap);
 364         return ERR_PTR(-ENOMEM);
 365 }
 366
 367 void ion_system_heap_destroy(struct ion_heap *heap)
 368 {
 369         struct ion_system_heap *sys_heap = container_of(heap,
 370                                                         struct ion_system_heap,
 371                                                         heap);
 372         int i;
 373
 374         for (i = 0; i < num_orders; i++)
 375                 ion_page_pool_destroy(sys_heap->pools[i]);
 376         kfree(sys_heap->pools);
 377         kfree(sys_heap);
 378 }
 379
 380 static int ion_system_contig_heap_allocate(struct ion_heap *heap,
 381                                            struct ion_buffer *buffer,
 382                                            unsigned long len,
 383                                            unsigned long align,
 384                                            unsigned long flags)
 385 {
 386         int order = get_order(len);
 387         struct page *page;
 388         struct sg_table *table;
 389         unsigned long i;
 390         int ret;
 391
 392         if (align > (PAGE_SIZE << order))
 393                 return -EINVAL;
 394
 395         page = alloc_pages(low_order_gfp_flags, order);
 396         if (!page)
 397                 return -ENOMEM;
 398
 399         split_page(page, order);
 400
 401         len = PAGE_ALIGN(len);
 402         for (i = len >> PAGE_SHIFT; i < (1 << order); i++)
 403                 __free_page(page + i);
 404
 405         table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
 406         if (!table) {
 407                 ret = -ENOMEM;
 408                 goto out;
 409         }
 410
 411         ret = sg_alloc_table(table, 1, GFP_KERNEL);
 412         if (ret)
 413                 goto out;
 414
 415         sg_set_page(table->sgl, page, len, 0);
 416
 417         buffer->priv_virt = table;
 418
 419         ion_pages_sync_for_device(NULL, page, len, DMA_BIDIRECTIONAL);
 420
 421         return 0;
 422
 423 out:
 424         for (i = 0; i < len >> PAGE_SHIFT; i++)
 425                 __free_page(page + i);
 426         kfree(table);
 427         return ret;
 428 }
 429
 430 static void ion_system_contig_heap_free(struct ion_buffer *buffer)
 431 {
 432         struct sg_table *table = buffer->priv_virt;
 433         struct page *page = sg_page(table->sgl);
 434         unsigned long pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
 435         unsigned long i;
 436
 437         for (i = 0; i < pages; i++)
 438                 __free_page(page + i);
 439         sg_free_table(table);
 440         kfree(table);
 441 }
 442
 443 static int ion_system_contig_heap_phys(struct ion_heap *heap,
 444                                        struct ion_buffer *buffer,
 445                                        ion_phys_addr_t *addr, size_t *len)
 446 {
 447         struct sg_table *table = buffer->priv_virt;
 448         struct page *page = sg_page(table->sgl);
 449         *addr = page_to_phys(page);
 450         *len = buffer->size;
 451         return 0;
 452 }
 453
 454 static struct sg_table *ion_system_contig_heap_map_dma(struct ion_heap *heap,
 455                                                 struct ion_buffer *buffer)
 456 {
 457         return buffer->priv_virt;
 458 }
 459
 460 static void ion_system_contig_heap_unmap_dma(struct ion_heap *heap,
 461                                              struct ion_buffer *buffer)
 462 {
 463 }
 464
 465 static struct ion_heap_ops kmalloc_ops = {
 466         .allocate = ion_system_contig_heap_allocate,
 467         .free = ion_system_contig_heap_free,
 468         .phys = ion_system_contig_heap_phys,
 469         .map_dma = ion_system_contig_heap_map_dma,
 470         .unmap_dma = ion_system_contig_heap_unmap_dma,
 471         .map_kernel = ion_heap_map_kernel,
 472         .unmap_kernel = ion_heap_unmap_kernel,
 473         .map_user = ion_heap_map_user,
 474 };
 475
 476 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
 477 {
 478         struct ion_heap *heap;
 479
 480         heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
 481         if (!heap)
 482                 return ERR_PTR(-ENOMEM);
 483         heap->ops = &kmalloc_ops;
 484         heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
 485         return heap;
 486 }
 487
 488 void ion_system_contig_heap_destroy(struct ion_heap *heap)
 489 {
 490         kfree(heap);
 491 }
 492