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_RECLAIM;
  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
  38         for (i = 0; i < num_orders; i++)
  39                 if (order == orders[i])
  40                         return i;
  41         BUG();
  42         return -1;
  43 }
  44
  45 static inline unsigned int order_to_size(int order)
  46 {
  47         return PAGE_SIZE << order;
  48 }
  49
  50 struct ion_system_heap {
  51         struct ion_heap heap;
  52         struct ion_page_pool *pools[0];
  53 };
  54
  55 static struct page *alloc_buffer_page(struct ion_system_heap *heap,
  56                                       struct ion_buffer *buffer,
  57                                       unsigned long order)
  58 {
  59         bool cached = ion_buffer_cached(buffer);
  60         struct ion_page_pool *pool = heap->pools[order_to_index(order)];
  61         struct page *page;
  62
  63         if (!cached) {
  64                 page = ion_page_pool_alloc(pool);
  65         } else {
  66                 gfp_t gfp_flags = low_order_gfp_flags;
  67
  68                 if (order > 4)
  69                         gfp_flags = high_order_gfp_flags;
  70                 page = alloc_pages(gfp_flags | __GFP_COMP, order);
  71                 if (!page)
  72                         return NULL;
  73                 ion_pages_sync_for_device(NULL, page, PAGE_SIZE << order,
  74                                                 DMA_BIDIRECTIONAL);
  75         }
  76
  77         return page;
  78 }
  79
  80 static void free_buffer_page(struct ion_system_heap *heap,
  81                              struct ion_buffer *buffer, struct page *page)
  82 {
  83         unsigned int order = compound_order(page);
  84         bool cached = ion_buffer_cached(buffer);
  85
  86         if (!cached && !(buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE)) {
  87                 struct ion_page_pool *pool = heap->pools[order_to_index(order)];
  88
  89                 ion_page_pool_free(pool, page);
  90         } else {
  91                 __free_pages(page, order);
  92         }
  93 }
  94
  95
  96 static struct page *alloc_largest_available(struct ion_system_heap *heap,
  97                                             struct ion_buffer *buffer,
  98                                             unsigned long size,
  99                                             unsigned int max_order)
 100 {
 101         struct page *page;
 102         int i;
 103
 104         for (i = 0; i < num_orders; i++) {
 105                 if (size < order_to_size(orders[i]))
 106                         continue;
 107                 if (max_order < orders[i])
 108                         continue;
 109
 110                 page = alloc_buffer_page(heap, buffer, orders[i]);
 111                 if (!page)
 112                         continue;
 113
 114                 return page;
 115         }
 116
 117         return NULL;
 118 }
 119
 120 static int ion_system_heap_allocate(struct ion_heap *heap,
 121                                      struct ion_buffer *buffer,
 122                                      unsigned long size, unsigned long align,
 123                                      unsigned long flags)
 124 {
 125         struct ion_system_heap *sys_heap = container_of(heap,
 126                                                         struct ion_system_heap,
 127                                                         heap);
 128         struct sg_table *table;
 129         struct scatterlist *sg;
 130         struct list_head pages;
 131         struct page *page, *tmp_page;
 132         int i = 0;
 133         unsigned long size_remaining = PAGE_ALIGN(size);
 134         unsigned int max_order = orders[0];
 135
 136         if (align > PAGE_SIZE)
 137                 return -EINVAL;
 138
 139         if (size / PAGE_SIZE > totalram_pages / 2)
 140                 return -ENOMEM;
 141
 142         INIT_LIST_HEAD(&pages);
 143         while (size_remaining > 0) {
 144                 page = alloc_largest_available(sys_heap, buffer, size_remaining,
 145                                                 max_order);
 146                 if (!page)
 147                         goto free_pages;
 148                 list_add_tail(&page->lru, &pages);
 149                 size_remaining -= PAGE_SIZE << compound_order(page);
 150                 max_order = compound_order(page);
 151                 i++;
 152         }
 153         table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
 154         if (!table)
 155                 goto free_pages;
 156
 157         if (sg_alloc_table(table, i, GFP_KERNEL))
 158                 goto free_table;
 159
 160         sg = table->sgl;
 161         list_for_each_entry_safe(page, tmp_page, &pages, lru) {
 162                 sg_set_page(sg, page, PAGE_SIZE << compound_order(page), 0);
 163                 sg = sg_next(sg);
 164                 list_del(&page->lru);
 165         }
 166
 167         buffer->priv_virt = table;
 168         return 0;
 169
 170 free_table:
 171         kfree(table);
 172 free_pages:
 173         list_for_each_entry_safe(page, tmp_page, &pages, lru)
 174                 free_buffer_page(sys_heap, buffer, page);
 175         return -ENOMEM;
 176 }
 177
 178 static void ion_system_heap_free(struct ion_buffer *buffer)
 179 {
 180         struct ion_system_heap *sys_heap = container_of(buffer->heap,
 181                                                         struct ion_system_heap,
 182                                                         heap);
 183         struct sg_table *table = buffer->sg_table;
 184         bool cached = ion_buffer_cached(buffer);
 185         struct scatterlist *sg;
 186         int i;
 187
 188         /*
 189          *  uncached pages come from the page pools, zero them before returning
 190          *  for security purposes (other allocations are zerod at
 191          *  alloc time
 192          */
 193         if (!cached && !(buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE))
 194                 ion_heap_buffer_zero(buffer);
 195
 196         for_each_sg(table->sgl, sg, table->nents, i)
 197                 free_buffer_page(sys_heap, buffer, sg_page(sg));
 198         sg_free_table(table);
 199         kfree(table);
 200 }
 201
 202 static struct sg_table *ion_system_heap_map_dma(struct ion_heap *heap,
 203                                                 struct ion_buffer *buffer)
 204 {
 205         return buffer->priv_virt;
 206 }
 207
 208 static void ion_system_heap_unmap_dma(struct ion_heap *heap,
 209                                       struct ion_buffer *buffer)
 210 {
 211 }
 212
 213 static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask,
 214                                         int nr_to_scan)
 215 {
 216         struct ion_system_heap *sys_heap;
 217         int nr_total = 0;
 218         int i, nr_freed;
 219         int only_scan = 0;
 220
 221         sys_heap = container_of(heap, struct ion_system_heap, heap);
 222
 223         if (!nr_to_scan)
 224                 only_scan = 1;
 225
 226         for (i = 0; i < num_orders; i++) {
 227                 struct ion_page_pool *pool = sys_heap->pools[i];
 228
 229                 nr_freed = ion_page_pool_shrink(pool, gfp_mask, nr_to_scan);
 230                 nr_total += nr_freed;
 231
 232                 if (!only_scan) {
 233                         nr_to_scan -= nr_freed;
 234                         /* shrink completed */
 235                         if (nr_to_scan <= 0)
 236                                 break;
 237                 }
 238         }
 239
 240         return nr_total;
 241 }
 242
 243 static struct ion_heap_ops system_heap_ops = {
 244         .allocate = ion_system_heap_allocate,
 245         .free = ion_system_heap_free,
 246         .map_dma = ion_system_heap_map_dma,
 247         .unmap_dma = ion_system_heap_unmap_dma,
 248         .map_kernel = ion_heap_map_kernel,
 249         .unmap_kernel = ion_heap_unmap_kernel,
 250         .map_user = ion_heap_map_user,
 251         .shrink = ion_system_heap_shrink,
 252 };
 253
 254 static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
 255                                       void *unused)
 256 {
 257
 258         struct ion_system_heap *sys_heap = container_of(heap,
 259                                                         struct ion_system_heap,
 260                                                         heap);
 261         int i;
 262
 263         for (i = 0; i < num_orders; i++) {
 264                 struct ion_page_pool *pool = sys_heap->pools[i];
 265
 266                 seq_printf(s, "%d order %u highmem pages in pool = %lu total\n",
 267                            pool->high_count, pool->order,
 268                            (PAGE_SIZE << pool->order) * pool->high_count);
 269                 seq_printf(s, "%d order %u lowmem pages in pool = %lu total\n",
 270                            pool->low_count, pool->order,
 271                            (PAGE_SIZE << pool->order) * pool->low_count);
 272         }
 273         return 0;
 274 }
 275
 276 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
 277 {
 278         struct ion_system_heap *heap;
 279         int i;
 280
 281         heap = kzalloc(sizeof(struct ion_system_heap) +
 282                         sizeof(struct ion_page_pool *) * num_orders,
 283                         GFP_KERNEL);
 284         if (!heap)
 285                 return ERR_PTR(-ENOMEM);
 286         heap->heap.ops = &system_heap_ops;
 287         heap->heap.type = ION_HEAP_TYPE_SYSTEM;
 288         heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
 289
 290         for (i = 0; i < num_orders; i++) {
 291                 struct ion_page_pool *pool;
 292                 gfp_t gfp_flags = low_order_gfp_flags;
 293
 294                 if (orders[i] > 4)
 295                         gfp_flags = high_order_gfp_flags;
 296                 pool = ion_page_pool_create(gfp_flags, orders[i]);
 297                 if (!pool)
 298                         goto destroy_pools;
 299                 heap->pools[i] = pool;
 300         }
 301
 302         heap->heap.debug_show = ion_system_heap_debug_show;
 303         return &heap->heap;
 304
 305 destroy_pools:
 306         while (i--)
 307                 ion_page_pool_destroy(heap->pools[i]);
 308         kfree(heap);
 309         return ERR_PTR(-ENOMEM);
 310 }
 311
 312 void ion_system_heap_destroy(struct ion_heap *heap)
 313 {
 314         struct ion_system_heap *sys_heap = container_of(heap,
 315                                                         struct ion_system_heap,
 316                                                         heap);
 317         int i;
 318
 319         for (i = 0; i < num_orders; i++)
 320                 ion_page_pool_destroy(sys_heap->pools[i]);
 321         kfree(sys_heap);
 322 }
 323
 324 static int ion_system_contig_heap_allocate(struct ion_heap *heap,
 325                                            struct ion_buffer *buffer,
 326                                            unsigned long len,
 327                                            unsigned long align,
 328                                            unsigned long flags)
 329 {
 330         int order = get_order(len);
 331         struct page *page;
 332         struct sg_table *table;
 333         unsigned long i;
 334         int ret;
 335
 336         if (align > (PAGE_SIZE << order))
 337                 return -EINVAL;
 338
 339         page = alloc_pages(low_order_gfp_flags, order);
 340         if (!page)
 341                 return -ENOMEM;
 342
 343         split_page(page, order);
 344
 345         len = PAGE_ALIGN(len);
 346         for (i = len >> PAGE_SHIFT; i < (1 << order); i++)
 347                 __free_page(page + i);
 348
 349         table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
 350         if (!table) {
 351                 ret = -ENOMEM;
 352                 goto free_pages;
 353         }
 354
 355         ret = sg_alloc_table(table, 1, GFP_KERNEL);
 356         if (ret)
 357                 goto free_table;
 358
 359         sg_set_page(table->sgl, page, len, 0);
 360
 361         buffer->priv_virt = table;
 362
 363         ion_pages_sync_for_device(NULL, page, len, DMA_BIDIRECTIONAL);
 364
 365         return 0;
 366
 367 free_table:
 368         kfree(table);
 369 free_pages:
 370         for (i = 0; i < len >> PAGE_SHIFT; i++)
 371                 __free_page(page + i);
 372
 373         return ret;
 374 }
 375
 376 static void ion_system_contig_heap_free(struct ion_buffer *buffer)
 377 {
 378         struct sg_table *table = buffer->priv_virt;
 379         struct page *page = sg_page(table->sgl);
 380         unsigned long pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
 381         unsigned long i;
 382
 383         for (i = 0; i < pages; i++)
 384                 __free_page(page + i);
 385         sg_free_table(table);
 386         kfree(table);
 387 }
 388
 389 static int ion_system_contig_heap_phys(struct ion_heap *heap,
 390                                        struct ion_buffer *buffer,
 391                                        ion_phys_addr_t *addr, size_t *len)
 392 {
 393         struct sg_table *table = buffer->priv_virt;
 394         struct page *page = sg_page(table->sgl);
 395         *addr = page_to_phys(page);
 396         *len = buffer->size;
 397         return 0;
 398 }
 399
 400 static struct sg_table *ion_system_contig_heap_map_dma(struct ion_heap *heap,
 401                                                 struct ion_buffer *buffer)
 402 {
 403         return buffer->priv_virt;
 404 }
 405
 406 static void ion_system_contig_heap_unmap_dma(struct ion_heap *heap,
 407                                              struct ion_buffer *buffer)
 408 {
 409 }
 410
 411 static struct ion_heap_ops kmalloc_ops = {
 412         .allocate = ion_system_contig_heap_allocate,
 413         .free = ion_system_contig_heap_free,
 414         .phys = ion_system_contig_heap_phys,
 415         .map_dma = ion_system_contig_heap_map_dma,
 416         .unmap_dma = ion_system_contig_heap_unmap_dma,
 417         .map_kernel = ion_heap_map_kernel,
 418         .unmap_kernel = ion_heap_unmap_kernel,
 419         .map_user = ion_heap_map_user,
 420 };
 421
 422 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
 423 {
 424         struct ion_heap *heap;
 425
 426         heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
 427         if (!heap)
 428                 return ERR_PTR(-ENOMEM);
 429         heap->ops = &kmalloc_ops;
 430         heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
 431         return heap;
 432 }
 433
 434 void ion_system_contig_heap_destroy(struct ion_heap *heap)
 435 {
 436         kfree(heap);
 437 }