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
  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         /* uncached pages come from the page pools, zero them before returning
 189            for security purposes (other allocations are zerod at alloc time */
 190         if (!cached && !(buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE))
 191                 ion_heap_buffer_zero(buffer);
 192
 193         for_each_sg(table->sgl, sg, table->nents, i)
 194                 free_buffer_page(sys_heap, buffer, sg_page(sg));
 195         sg_free_table(table);
 196         kfree(table);
 197 }
 198
 199 static struct sg_table *ion_system_heap_map_dma(struct ion_heap *heap,
 200                                                 struct ion_buffer *buffer)
 201 {
 202         return buffer->priv_virt;
 203 }
 204
 205 static void ion_system_heap_unmap_dma(struct ion_heap *heap,
 206                                       struct ion_buffer *buffer)
 207 {
 208 }
 209
 210 static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask,
 211                                         int nr_to_scan)
 212 {
 213         struct ion_system_heap *sys_heap;
 214         int nr_total = 0;
 215         int i, nr_freed;
 216         int only_scan = 0;
 217
 218         sys_heap = container_of(heap, struct ion_system_heap, heap);
 219
 220         if (!nr_to_scan)
 221                 only_scan = 1;
 222
 223         for (i = 0; i < num_orders; i++) {
 224                 struct ion_page_pool *pool = sys_heap->pools[i];
 225
 226                 nr_freed = ion_page_pool_shrink(pool, gfp_mask, nr_to_scan);
 227                 nr_total += nr_freed;
 228
 229                 if (!only_scan) {
 230                         nr_to_scan -= nr_freed;
 231                         /* shrink completed */
 232                         if (nr_to_scan <= 0)
 233                                 break;
 234                 }
 235         }
 236
 237         return nr_total;
 238 }
 239
 240 static struct ion_heap_ops system_heap_ops = {
 241         .allocate = ion_system_heap_allocate,
 242         .free = ion_system_heap_free,
 243         .map_dma = ion_system_heap_map_dma,
 244         .unmap_dma = ion_system_heap_unmap_dma,
 245         .map_kernel = ion_heap_map_kernel,
 246         .unmap_kernel = ion_heap_unmap_kernel,
 247         .map_user = ion_heap_map_user,
 248         .shrink = ion_system_heap_shrink,
 249 };
 250
 251 static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
 252                                       void *unused)
 253 {
 254
 255         struct ion_system_heap *sys_heap = container_of(heap,
 256                                                         struct ion_system_heap,
 257                                                         heap);
 258         int i;
 259
 260         for (i = 0; i < num_orders; i++) {
 261                 struct ion_page_pool *pool = sys_heap->pools[i];
 262
 263                 seq_printf(s, "%d order %u highmem pages in pool = %lu total\n",
 264                            pool->high_count, pool->order,
 265                            (PAGE_SIZE << pool->order) * pool->high_count);
 266                 seq_printf(s, "%d order %u lowmem pages in pool = %lu total\n",
 267                            pool->low_count, pool->order,
 268                            (PAGE_SIZE << pool->order) * pool->low_count);
 269         }
 270         return 0;
 271 }
 272
 273 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
 274 {
 275         struct ion_system_heap *heap;
 276         int i;
 277
 278         heap = kzalloc(sizeof(struct ion_system_heap) +
 279                         sizeof(struct ion_page_pool *) * num_orders,
 280                         GFP_KERNEL);
 281         if (!heap)
 282                 return ERR_PTR(-ENOMEM);
 283         heap->heap.ops = &system_heap_ops;
 284         heap->heap.type = ION_HEAP_TYPE_SYSTEM;
 285         heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
 286
 287         for (i = 0; i < num_orders; i++) {
 288                 struct ion_page_pool *pool;
 289                 gfp_t gfp_flags = low_order_gfp_flags;
 290
 291                 if (orders[i] > 4)
 292                         gfp_flags = high_order_gfp_flags;
 293                 pool = ion_page_pool_create(gfp_flags, orders[i]);
 294                 if (!pool)
 295                         goto destroy_pools;
 296                 heap->pools[i] = pool;
 297         }
 298
 299         heap->heap.debug_show = ion_system_heap_debug_show;
 300         return &heap->heap;
 301
 302 destroy_pools:
 303         while (i--)
 304                 ion_page_pool_destroy(heap->pools[i]);
 305         kfree(heap);
 306         return ERR_PTR(-ENOMEM);
 307 }
 308
 309 void ion_system_heap_destroy(struct ion_heap *heap)
 310 {
 311         struct ion_system_heap *sys_heap = container_of(heap,
 312                                                         struct ion_system_heap,
 313                                                         heap);
 314         int i;
 315
 316         for (i = 0; i < num_orders; i++)
 317                 ion_page_pool_destroy(sys_heap->pools[i]);
 318         kfree(sys_heap);
 319 }
 320
 321 static int ion_system_contig_heap_allocate(struct ion_heap *heap,
 322                                            struct ion_buffer *buffer,
 323                                            unsigned long len,
 324                                            unsigned long align,
 325                                            unsigned long flags)
 326 {
 327         int order = get_order(len);
 328         struct page *page;
 329         struct sg_table *table;
 330         unsigned long i;
 331         int ret;
 332
 333         if (align > (PAGE_SIZE << order))
 334                 return -EINVAL;
 335
 336         page = alloc_pages(low_order_gfp_flags, order);
 337         if (!page)
 338                 return -ENOMEM;
 339
 340         split_page(page, order);
 341
 342         len = PAGE_ALIGN(len);
 343         for (i = len >> PAGE_SHIFT; i < (1 << order); i++)
 344                 __free_page(page + i);
 345
 346         table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
 347         if (!table) {
 348                 ret = -ENOMEM;
 349                 goto free_pages;
 350         }
 351
 352         ret = sg_alloc_table(table, 1, GFP_KERNEL);
 353         if (ret)
 354                 goto free_table;
 355
 356         sg_set_page(table->sgl, page, len, 0);
 357
 358         buffer->priv_virt = table;
 359
 360         ion_pages_sync_for_device(NULL, page, len, DMA_BIDIRECTIONAL);
 361
 362         return 0;
 363
 364 free_table:
 365         kfree(table);
 366 free_pages:
 367         for (i = 0; i < len >> PAGE_SHIFT; i++)
 368                 __free_page(page + i);
 369
 370         return ret;
 371 }
 372
 373 static void ion_system_contig_heap_free(struct ion_buffer *buffer)
 374 {
 375         struct sg_table *table = buffer->priv_virt;
 376         struct page *page = sg_page(table->sgl);
 377         unsigned long pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
 378         unsigned long i;
 379
 380         for (i = 0; i < pages; i++)
 381                 __free_page(page + i);
 382         sg_free_table(table);
 383         kfree(table);
 384 }
 385
 386 static int ion_system_contig_heap_phys(struct ion_heap *heap,
 387                                        struct ion_buffer *buffer,
 388                                        ion_phys_addr_t *addr, size_t *len)
 389 {
 390         struct sg_table *table = buffer->priv_virt;
 391         struct page *page = sg_page(table->sgl);
 392         *addr = page_to_phys(page);
 393         *len = buffer->size;
 394         return 0;
 395 }
 396
 397 static struct sg_table *ion_system_contig_heap_map_dma(struct ion_heap *heap,
 398                                                 struct ion_buffer *buffer)
 399 {
 400         return buffer->priv_virt;
 401 }
 402
 403 static void ion_system_contig_heap_unmap_dma(struct ion_heap *heap,
 404                                              struct ion_buffer *buffer)
 405 {
 406 }
 407
 408 static struct ion_heap_ops kmalloc_ops = {
 409         .allocate = ion_system_contig_heap_allocate,
 410         .free = ion_system_contig_heap_free,
 411         .phys = ion_system_contig_heap_phys,
 412         .map_dma = ion_system_contig_heap_map_dma,
 413         .unmap_dma = ion_system_contig_heap_unmap_dma,
 414         .map_kernel = ion_heap_map_kernel,
 415         .unmap_kernel = ion_heap_unmap_kernel,
 416         .map_user = ion_heap_map_user,
 417 };
 418
 419 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
 420 {
 421         struct ion_heap *heap;
 422
 423         heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
 424         if (!heap)
 425                 return ERR_PTR(-ENOMEM);
 426         heap->ops = &kmalloc_ops;
 427         heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
 428         return heap;
 429 }
 430
 431 void ion_system_contig_heap_destroy(struct ion_heap *heap)
 432 {
 433         kfree(heap);
 434 }