]> Pileus Git - ~andy/linux/blob - drivers/staging/android/ion/ion_system_heap.c
ion: Update system heap shrinker to use the new count/scan interface
[~andy/linux] / 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,
152                                                 max_order);
153                 if (!info)
154                         goto err;
155                 list_add_tail(&info->list, &pages);
156                 size_remaining -= (1 << info->order) * PAGE_SIZE;
157                 max_order = info->order;
158                 i++;
159         }
160         table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
161         if (!table)
162                 goto err;
163
164         ret = sg_alloc_table(table, i, GFP_KERNEL);
165         if (ret)
166                 goto err1;
167
168         sg = table->sgl;
169         list_for_each_entry_safe(info, tmp_info, &pages, list) {
170                 struct page *page = info->page;
171                 sg_set_page(sg, page, (1 << info->order) * PAGE_SIZE, 0);
172                 sg = sg_next(sg);
173                 list_del(&info->list);
174                 kfree(info);
175         }
176
177         buffer->priv_virt = table;
178         return 0;
179 err1:
180         kfree(table);
181 err:
182         list_for_each_entry_safe(info, tmp_info, &pages, list) {
183                 free_buffer_page(sys_heap, buffer, info->page, info->order);
184                 kfree(info);
185         }
186         return -ENOMEM;
187 }
188
189 static void ion_system_heap_free(struct ion_buffer *buffer)
190 {
191         struct ion_heap *heap = buffer->heap;
192         struct ion_system_heap *sys_heap = container_of(heap,
193                                                         struct ion_system_heap,
194                                                         heap);
195         struct sg_table *table = buffer->sg_table;
196         bool cached = ion_buffer_cached(buffer);
197         struct scatterlist *sg;
198         LIST_HEAD(pages);
199         int i;
200
201         /* uncached pages come from the page pools, zero them before returning
202            for security purposes (other allocations are zerod at alloc time */
203         if (!cached)
204                 ion_heap_buffer_zero(buffer);
205
206         for_each_sg(table->sgl, sg, table->nents, i)
207                 free_buffer_page(sys_heap, buffer, sg_page(sg),
208                                 get_order(sg->length));
209         sg_free_table(table);
210         kfree(table);
211 }
212
213 static struct sg_table *ion_system_heap_map_dma(struct ion_heap *heap,
214                                                 struct ion_buffer *buffer)
215 {
216         return buffer->priv_virt;
217 }
218
219 static void ion_system_heap_unmap_dma(struct ion_heap *heap,
220                                       struct ion_buffer *buffer)
221 {
222         return;
223 }
224
225 static struct ion_heap_ops system_heap_ops = {
226         .allocate = ion_system_heap_allocate,
227         .free = ion_system_heap_free,
228         .map_dma = ion_system_heap_map_dma,
229         .unmap_dma = ion_system_heap_unmap_dma,
230         .map_kernel = ion_heap_map_kernel,
231         .unmap_kernel = ion_heap_unmap_kernel,
232         .map_user = ion_heap_map_user,
233 };
234
235 static unsigned long ion_system_heap_shrink_count(struct shrinker *shrinker,
236                                   struct shrink_control *sc)
237 {
238         struct ion_heap *heap = container_of(shrinker, struct ion_heap,
239                                              shrinker);
240         struct ion_system_heap *sys_heap = container_of(heap,
241                                                         struct ion_system_heap,
242                                                         heap);
243         int nr_total = 0;
244         int i;
245
246         /* total number of items is whatever the page pools are holding
247            plus whatever's in the freelist */
248         for (i = 0; i < num_orders; i++) {
249                 struct ion_page_pool *pool = sys_heap->pools[i];
250                 nr_total += ion_page_pool_shrink(pool, sc->gfp_mask, 0);
251         }
252         nr_total += ion_heap_freelist_size(heap) / PAGE_SIZE;
253         return nr_total;
254
255 }
256
257 static unsigned long ion_system_heap_shrink_scan(struct shrinker *shrinker,
258                                   struct shrink_control *sc)
259 {
260
261         struct ion_heap *heap = container_of(shrinker, struct ion_heap,
262                                              shrinker);
263         struct ion_system_heap *sys_heap = container_of(heap,
264                                                         struct ion_system_heap,
265                                                         heap);
266         int nr_freed = 0;
267         int i;
268
269         if (sc->nr_to_scan == 0)
270                 goto end;
271
272         /* shrink the free list first, no point in zeroing the memory if
273            we're just going to reclaim it */
274         nr_freed += ion_heap_freelist_drain(heap, sc->nr_to_scan * PAGE_SIZE) /
275                 PAGE_SIZE;
276
277         if (nr_freed >= sc->nr_to_scan)
278                 goto end;
279
280         for (i = 0; i < num_orders; i++) {
281                 struct ion_page_pool *pool = sys_heap->pools[i];
282
283                 nr_freed += ion_page_pool_shrink(pool, sc->gfp_mask,
284                                                  sc->nr_to_scan);
285                 if (nr_freed >= sc->nr_to_scan)
286                         break;
287         }
288
289 end:
290         return nr_freed;
291
292 }
293
294 static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
295                                       void *unused)
296 {
297
298         struct ion_system_heap *sys_heap = container_of(heap,
299                                                         struct ion_system_heap,
300                                                         heap);
301         int i;
302         for (i = 0; i < num_orders; i++) {
303                 struct ion_page_pool *pool = sys_heap->pools[i];
304                 seq_printf(s, "%d order %u highmem pages in pool = %lu total\n",
305                            pool->high_count, pool->order,
306                            (1 << pool->order) * PAGE_SIZE * pool->high_count);
307                 seq_printf(s, "%d order %u lowmem pages in pool = %lu total\n",
308                            pool->low_count, pool->order,
309                            (1 << pool->order) * PAGE_SIZE * pool->low_count);
310         }
311         return 0;
312 }
313
314 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
315 {
316         struct ion_system_heap *heap;
317         int i;
318
319         heap = kzalloc(sizeof(struct ion_system_heap), GFP_KERNEL);
320         if (!heap)
321                 return ERR_PTR(-ENOMEM);
322         heap->heap.ops = &system_heap_ops;
323         heap->heap.type = ION_HEAP_TYPE_SYSTEM;
324         heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
325         heap->pools = kzalloc(sizeof(struct ion_page_pool *) * num_orders,
326                               GFP_KERNEL);
327         if (!heap->pools)
328                 goto err_alloc_pools;
329         for (i = 0; i < num_orders; i++) {
330                 struct ion_page_pool *pool;
331                 gfp_t gfp_flags = low_order_gfp_flags;
332
333                 if (orders[i] > 4)
334                         gfp_flags = high_order_gfp_flags;
335                 pool = ion_page_pool_create(gfp_flags, orders[i]);
336                 if (!pool)
337                         goto err_create_pool;
338                 heap->pools[i] = pool;
339         }
340
341         heap->heap.shrinker.scan_objects = ion_system_heap_shrink_scan;
342         heap->heap.shrinker.count_objects = ion_system_heap_shrink_count;
343         heap->heap.shrinker.seeks = DEFAULT_SEEKS;
344         heap->heap.shrinker.batch = 0;
345         register_shrinker(&heap->heap.shrinker);
346         heap->heap.debug_show = ion_system_heap_debug_show;
347         return &heap->heap;
348 err_create_pool:
349         for (i = 0; i < num_orders; i++)
350                 if (heap->pools[i])
351                         ion_page_pool_destroy(heap->pools[i]);
352         kfree(heap->pools);
353 err_alloc_pools:
354         kfree(heap);
355         return ERR_PTR(-ENOMEM);
356 }
357
358 void ion_system_heap_destroy(struct ion_heap *heap)
359 {
360         struct ion_system_heap *sys_heap = container_of(heap,
361                                                         struct ion_system_heap,
362                                                         heap);
363         int i;
364
365         for (i = 0; i < num_orders; i++)
366                 ion_page_pool_destroy(sys_heap->pools[i]);
367         kfree(sys_heap->pools);
368         kfree(sys_heap);
369 }
370
371 static int ion_system_contig_heap_allocate(struct ion_heap *heap,
372                                            struct ion_buffer *buffer,
373                                            unsigned long len,
374                                            unsigned long align,
375                                            unsigned long flags)
376 {
377         int order = get_order(len);
378         struct page *page;
379         struct sg_table *table;
380         unsigned long i;
381         int ret;
382
383         if (align > (PAGE_SIZE << order))
384                 return -EINVAL;
385
386         page = alloc_pages(low_order_gfp_flags, order);
387         if (!page)
388                 return -ENOMEM;
389
390         split_page(page, order);
391
392         len = PAGE_ALIGN(len);
393         for (i = len >> PAGE_SHIFT; i < (1 << order); i++)
394                 __free_page(page + i);
395
396         table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
397         if (!table) {
398                 ret = -ENOMEM;
399                 goto out;
400         }
401
402         ret = sg_alloc_table(table, 1, GFP_KERNEL);
403         if (ret)
404                 goto out;
405
406         sg_set_page(table->sgl, page, len, 0);
407
408         buffer->priv_virt = table;
409
410         ion_pages_sync_for_device(NULL, page, len, DMA_BIDIRECTIONAL);
411
412         return 0;
413
414 out:
415         for (i = 0; i < len >> PAGE_SHIFT; i++)
416                 __free_page(page + i);
417         kfree(table);
418         return ret;
419 }
420
421 static void ion_system_contig_heap_free(struct ion_buffer *buffer)
422 {
423         struct sg_table *table = buffer->priv_virt;
424         struct page *page = sg_page(table->sgl);
425         unsigned long pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
426         unsigned long i;
427
428         for (i = 0; i < pages; i++)
429                 __free_page(page + i);
430         sg_free_table(table);
431         kfree(table);
432 }
433
434 static int ion_system_contig_heap_phys(struct ion_heap *heap,
435                                        struct ion_buffer *buffer,
436                                        ion_phys_addr_t *addr, size_t *len)
437 {
438         struct sg_table *table = buffer->priv_virt;
439         struct page *page = sg_page(table->sgl);
440         *addr = page_to_phys(page);
441         *len = buffer->size;
442         return 0;
443 }
444
445 static struct sg_table *ion_system_contig_heap_map_dma(struct ion_heap *heap,
446                                                 struct ion_buffer *buffer)
447 {
448         return buffer->priv_virt;
449 }
450
451 static void ion_system_contig_heap_unmap_dma(struct ion_heap *heap,
452                                              struct ion_buffer *buffer)
453 {
454 }
455
456 static struct ion_heap_ops kmalloc_ops = {
457         .allocate = ion_system_contig_heap_allocate,
458         .free = ion_system_contig_heap_free,
459         .phys = ion_system_contig_heap_phys,
460         .map_dma = ion_system_contig_heap_map_dma,
461         .unmap_dma = ion_system_contig_heap_unmap_dma,
462         .map_kernel = ion_heap_map_kernel,
463         .unmap_kernel = ion_heap_unmap_kernel,
464         .map_user = ion_heap_map_user,
465 };
466
467 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
468 {
469         struct ion_heap *heap;
470
471         heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
472         if (!heap)
473                 return ERR_PTR(-ENOMEM);
474         heap->ops = &kmalloc_ops;
475         heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
476         return heap;
477 }
478
479 void ion_system_contig_heap_destroy(struct ion_heap *heap)
480 {
481         kfree(heap);
482 }
483