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