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