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         for (i = 0; i < num_orders; i++) {
 112                 if (size < order_to_size(orders[i]))
 113                         continue;
 114                 if (max_order < orders[i])
 115                         continue;
 116
 117                 page = alloc_buffer_page(heap, buffer, orders[i]);
 118                 if (!page)
 119                         continue;
 120
 121                 info = kmalloc(sizeof(struct page_info), GFP_KERNEL);
 122                 info->page = page;
 123                 info->order = orders[i];
 124                 return info;
 125         }
 126         return NULL;
 127 }
 128
 129 static int ion_system_heap_allocate(struct ion_heap *heap,
 130                                      struct ion_buffer *buffer,
 131                                      unsigned long size, unsigned long align,
 132                                      unsigned long flags)
 133 {
 134         struct ion_system_heap *sys_heap = container_of(heap,
 135                                                         struct ion_system_heap,
 136                                                         heap);
 137         struct sg_table *table;
 138         struct scatterlist *sg;
 139         int ret;
 140         struct list_head pages;
 141         struct page_info *info, *tmp_info;
 142         int i = 0;
 143         long size_remaining = PAGE_ALIGN(size);
 144         unsigned int max_order = orders[0];
 145
 146         if (align > PAGE_SIZE)
 147                 return -EINVAL;
 148
 149         INIT_LIST_HEAD(&pages);
 150         while (size_remaining > 0) {
 151                 info = alloc_largest_available(sys_heap, buffer, size_remaining, max_order);
 152                 if (!info)
 153                         goto err;
 154                 list_add_tail(&info->list, &pages);
 155                 size_remaining -= (1 << info->order) * PAGE_SIZE;
 156                 max_order = info->order;
 157                 i++;
 158         }
 159         table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
 160         if (!table)
 161                 goto err;
 162
 163         ret = sg_alloc_table(table, i, GFP_KERNEL);
 164         if (ret)
 165                 goto err1;
 166
 167         sg = table->sgl;
 168         list_for_each_entry_safe(info, tmp_info, &pages, list) {
 169                 struct page *page = info->page;
 170                 sg_set_page(sg, page, (1 << info->order) * PAGE_SIZE, 0);
 171                 sg = sg_next(sg);
 172                 list_del(&info->list);
 173                 kfree(info);
 174         }
 175
 176         buffer->priv_virt = table;
 177         return 0;
 178 err1:
 179         kfree(table);
 180 err:
 181         list_for_each_entry_safe(info, tmp_info, &pages, list) {
 182                 free_buffer_page(sys_heap, buffer, info->page, info->order);
 183                 kfree(info);
 184         }
 185         return -ENOMEM;
 186 }
 187
 188 static void ion_system_heap_free(struct ion_buffer *buffer)
 189 {
 190         struct ion_heap *heap = buffer->heap;
 191         struct ion_system_heap *sys_heap = container_of(heap,
 192                                                         struct ion_system_heap,
 193                                                         heap);
 194         struct sg_table *table = buffer->sg_table;
 195         bool cached = ion_buffer_cached(buffer);
 196         struct scatterlist *sg;
 197         LIST_HEAD(pages);
 198         int i;
 199
 200         /* uncached pages come from the page pools, zero them before returning
 201            for security purposes (other allocations are zerod at alloc time */
 202         if (!cached)
 203                 ion_heap_buffer_zero(buffer);
 204
 205         for_each_sg(table->sgl, sg, table->nents, i)
 206                 free_buffer_page(sys_heap, buffer, sg_page(sg),
 207                                 get_order(sg->length));
 208         sg_free_table(table);
 209         kfree(table);
 210 }
 211
 212 static struct sg_table *ion_system_heap_map_dma(struct ion_heap *heap,
 213                                                 struct ion_buffer *buffer)
 214 {
 215         return buffer->priv_virt;
 216 }
 217
 218 static void ion_system_heap_unmap_dma(struct ion_heap *heap,
 219                                       struct ion_buffer *buffer)
 220 {
 221         return;
 222 }
 223
 224 static struct ion_heap_ops system_heap_ops = {
 225         .allocate = ion_system_heap_allocate,
 226         .free = ion_system_heap_free,
 227         .map_dma = ion_system_heap_map_dma,
 228         .unmap_dma = ion_system_heap_unmap_dma,
 229         .map_kernel = ion_heap_map_kernel,
 230         .unmap_kernel = ion_heap_unmap_kernel,
 231         .map_user = ion_heap_map_user,
 232 };
 233
 234 static int ion_system_heap_shrink(struct shrinker *shrinker,
 235                                   struct shrink_control *sc) {
 236
 237         struct ion_heap *heap = container_of(shrinker, struct ion_heap,
 238                                              shrinker);
 239         struct ion_system_heap *sys_heap = container_of(heap,
 240                                                         struct ion_system_heap,
 241                                                         heap);
 242         int nr_total = 0;
 243         int nr_freed = 0;
 244         int i;
 245
 246         if (sc->nr_to_scan == 0)
 247                 goto end;
 248
 249         /* shrink the free list first, no point in zeroing the memory if
 250            we're just going to reclaim it */
 251         nr_freed += ion_heap_freelist_drain(heap, sc->nr_to_scan * PAGE_SIZE) /
 252                 PAGE_SIZE;
 253
 254         if (nr_freed >= sc->nr_to_scan)
 255                 goto end;
 256
 257         for (i = 0; i < num_orders; i++) {
 258                 struct ion_page_pool *pool = sys_heap->pools[i];
 259
 260                 nr_freed += ion_page_pool_shrink(pool, sc->gfp_mask,
 261                                                  sc->nr_to_scan);
 262                 if (nr_freed >= sc->nr_to_scan)
 263                         break;
 264         }
 265
 266 end:
 267         /* total number of items is whatever the page pools are holding
 268            plus whatever's in the freelist */
 269         for (i = 0; i < num_orders; i++) {
 270                 struct ion_page_pool *pool = sys_heap->pools[i];
 271                 nr_total += ion_page_pool_shrink(pool, sc->gfp_mask, 0);
 272         }
 273         nr_total += ion_heap_freelist_size(heap) / PAGE_SIZE;
 274         return nr_total;
 275
 276 }
 277
 278 static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
 279                                       void *unused)
 280 {
 281
 282         struct ion_system_heap *sys_heap = container_of(heap,
 283                                                         struct ion_system_heap,
 284                                                         heap);
 285         int i;
 286         for (i = 0; i < num_orders; i++) {
 287                 struct ion_page_pool *pool = sys_heap->pools[i];
 288                 seq_printf(s, "%d order %u highmem pages in pool = %lu total\n",
 289                            pool->high_count, pool->order,
 290                            (1 << pool->order) * PAGE_SIZE * pool->high_count);
 291                 seq_printf(s, "%d order %u lowmem pages in pool = %lu total\n",
 292                            pool->low_count, pool->order,
 293                            (1 << pool->order) * PAGE_SIZE * pool->low_count);
 294         }
 295         return 0;
 296 }
 297
 298 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
 299 {
 300         struct ion_system_heap *heap;
 301         int i;
 302
 303         heap = kzalloc(sizeof(struct ion_system_heap), GFP_KERNEL);
 304         if (!heap)
 305                 return ERR_PTR(-ENOMEM);
 306         heap->heap.ops = &system_heap_ops;
 307         heap->heap.type = ION_HEAP_TYPE_SYSTEM;
 308         heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
 309         heap->pools = kzalloc(sizeof(struct ion_page_pool *) * num_orders,
 310                               GFP_KERNEL);
 311         if (!heap->pools)
 312                 goto err_alloc_pools;
 313         for (i = 0; i < num_orders; i++) {
 314                 struct ion_page_pool *pool;
 315                 gfp_t gfp_flags = low_order_gfp_flags;
 316
 317                 if (orders[i] > 4)
 318                         gfp_flags = high_order_gfp_flags;
 319                 pool = ion_page_pool_create(gfp_flags, orders[i]);
 320                 if (!pool)
 321                         goto err_create_pool;
 322                 heap->pools[i] = pool;
 323         }
 324
 325         heap->heap.shrinker.shrink = ion_system_heap_shrink;
 326         heap->heap.shrinker.seeks = DEFAULT_SEEKS;
 327         heap->heap.shrinker.batch = 0;
 328         register_shrinker(&heap->heap.shrinker);
 329         heap->heap.debug_show = ion_system_heap_debug_show;
 330         return &heap->heap;
 331 err_create_pool:
 332         for (i = 0; i < num_orders; i++)
 333                 if (heap->pools[i])
 334                         ion_page_pool_destroy(heap->pools[i]);
 335         kfree(heap->pools);
 336 err_alloc_pools:
 337         kfree(heap);
 338         return ERR_PTR(-ENOMEM);
 339 }
 340
 341 void ion_system_heap_destroy(struct ion_heap *heap)
 342 {
 343         struct ion_system_heap *sys_heap = container_of(heap,
 344                                                         struct ion_system_heap,
 345                                                         heap);
 346         int i;
 347
 348         for (i = 0; i < num_orders; i++)
 349                 ion_page_pool_destroy(sys_heap->pools[i]);
 350         kfree(sys_heap->pools);
 351         kfree(sys_heap);
 352 }
 353
 354 static int ion_system_contig_heap_allocate(struct ion_heap *heap,
 355                                            struct ion_buffer *buffer,
 356                                            unsigned long len,
 357                                            unsigned long align,
 358                                            unsigned long flags)
 359 {
 360         int order = get_order(len);
 361         struct page *page;
 362         struct sg_table *table;
 363         unsigned long i;
 364         int ret;
 365
 366         if (align > (PAGE_SIZE << order))
 367                 return -EINVAL;
 368
 369         page = alloc_pages(low_order_gfp_flags, order);
 370         if (!page)
 371                 return -ENOMEM;
 372
 373         split_page(page, order);
 374
 375         len = PAGE_ALIGN(len);
 376         for (i = len >> PAGE_SHIFT; i < (1 << order); i++)
 377                 __free_page(page + i);
 378
 379         table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
 380         if (!table) {
 381                 ret = -ENOMEM;
 382                 goto out;
 383         }
 384
 385         ret = sg_alloc_table(table, 1, GFP_KERNEL);
 386         if (ret)
 387                 goto out;
 388
 389         sg_set_page(table->sgl, page, len, 0);
 390
 391         buffer->priv_virt = table;
 392
 393         ion_pages_sync_for_device(NULL, page, len, DMA_BIDIRECTIONAL);
 394
 395         return 0;
 396
 397 out:
 398         for (i = 0; i < len >> PAGE_SHIFT; i++)
 399                 __free_page(page + i);
 400         kfree(table);
 401         return ret;
 402 }
 403
 404 static void ion_system_contig_heap_free(struct ion_buffer *buffer)
 405 {
 406         struct sg_table *table = buffer->priv_virt;
 407         struct page *page = sg_page(table->sgl);
 408         unsigned long pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
 409         unsigned long i;
 410
 411         for (i = 0; i < pages; i++)
 412                 __free_page(page + i);
 413         sg_free_table(table);
 414         kfree(table);
 415 }
 416
 417 static int ion_system_contig_heap_phys(struct ion_heap *heap,
 418                                        struct ion_buffer *buffer,
 419                                        ion_phys_addr_t *addr, size_t *len)
 420 {
 421         struct sg_table *table = buffer->priv_virt;
 422         struct page *page = sg_page(table->sgl);
 423         *addr = page_to_phys(page);
 424         *len = buffer->size;
 425         return 0;
 426 }
 427
 428 static struct sg_table *ion_system_contig_heap_map_dma(struct ion_heap *heap,
 429                                                 struct ion_buffer *buffer)
 430 {
 431         return buffer->priv_virt;
 432 }
 433
 434 static void ion_system_contig_heap_unmap_dma(struct ion_heap *heap,
 435                                              struct ion_buffer *buffer)
 436 {
 437 }
 438
 439 static struct ion_heap_ops kmalloc_ops = {
 440         .allocate = ion_system_contig_heap_allocate,
 441         .free = ion_system_contig_heap_free,
 442         .phys = ion_system_contig_heap_phys,
 443         .map_dma = ion_system_contig_heap_map_dma,
 444         .unmap_dma = ion_system_contig_heap_unmap_dma,
 445         .map_kernel = ion_heap_map_kernel,
 446         .unmap_kernel = ion_heap_unmap_kernel,
 447         .map_user = ion_heap_map_user,
 448 };
 449
 450 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
 451 {
 452         struct ion_heap *heap;
 453
 454         heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
 455         if (!heap)
 456                 return ERR_PTR(-ENOMEM);
 457         heap->ops = &kmalloc_ops;
 458         heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
 459         return heap;
 460 }
 461
 462 void ion_system_contig_heap_destroy(struct ion_heap *heap)
 463 {
 464         kfree(heap);
 465 }
 466