2 * drivers/staging/android/ion/ion_priv.h
4 * Copyright (C) 2011 Google, Inc.
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.
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.
20 #include <linux/device.h>
21 #include <linux/dma-direction.h>
22 #include <linux/kref.h>
23 #include <linux/mm_types.h>
24 #include <linux/mutex.h>
25 #include <linux/rbtree.h>
26 #include <linux/sched.h>
27 #include <linux/shrinker.h>
28 #include <linux/types.h>
32 struct ion_buffer *ion_handle_buffer(struct ion_handle *handle);
35 * struct ion_buffer - metadata for a particular buffer
36 * @ref: reference count
37 * @node: node in the ion_device buffers tree
38 * @dev: back pointer to the ion_device
39 * @heap: back pointer to the heap the buffer came from
40 * @flags: buffer specific flags
41 * @private_flags: internal buffer specific flags
42 * @size: size of the buffer
43 * @priv_virt: private data to the buffer representable as
45 * @priv_phys: private data to the buffer representable as
46 * an ion_phys_addr_t (and someday a phys_addr_t)
47 * @lock: protects the buffers cnt fields
48 * @kmap_cnt: number of times the buffer is mapped to the kernel
49 * @vaddr: the kernel mapping if kmap_cnt is not zero
50 * @dmap_cnt: number of times the buffer is mapped for dma
51 * @sg_table: the sg table for the buffer if dmap_cnt is not zero
52 * @pages: flat array of pages in the buffer -- used by fault
53 * handler and only valid for buffers that are faulted in
54 * @vmas: list of vma's mapping this buffer
55 * @handle_count: count of handles referencing this buffer
56 * @task_comm: taskcomm of last client to reference this buffer in a
57 * handle, used for debugging
58 * @pid: pid of last client to reference this buffer in a
59 * handle, used for debugging
65 struct list_head list;
67 struct ion_device *dev;
68 struct ion_heap *heap;
70 unsigned long private_flags;
74 ion_phys_addr_t priv_phys;
80 struct sg_table *sg_table;
82 struct list_head vmas;
83 /* used to track orphaned buffers */
85 char task_comm[TASK_COMM_LEN];
88 void ion_buffer_destroy(struct ion_buffer *buffer);
91 * struct ion_heap_ops - ops to operate on a given heap
92 * @allocate: allocate memory
94 * @phys get physical address of a buffer (only define on
95 * physically contiguous heaps)
96 * @map_dma map the memory for dma to a scatterlist
97 * @unmap_dma unmap the memory for dma
98 * @map_kernel map memory to the kernel
99 * @unmap_kernel unmap memory to the kernel
100 * @map_user map memory to userspace
102 * allocate, phys, and map_user return 0 on success, -errno on error.
103 * map_dma and map_kernel return pointer on success, ERR_PTR on
104 * error. @free will be called with ION_PRIV_FLAG_SHRINKER_FREE set in
105 * the buffer's private_flags when called from a shrinker. In that
106 * case, the pages being free'd must be truly free'd back to the
107 * system, not put in a page pool or otherwise cached.
109 struct ion_heap_ops {
110 int (*allocate)(struct ion_heap *heap,
111 struct ion_buffer *buffer, unsigned long len,
112 unsigned long align, unsigned long flags);
113 void (*free)(struct ion_buffer *buffer);
114 int (*phys)(struct ion_heap *heap, struct ion_buffer *buffer,
115 ion_phys_addr_t *addr, size_t *len);
116 struct sg_table * (*map_dma)(struct ion_heap *heap,
117 struct ion_buffer *buffer);
118 void (*unmap_dma)(struct ion_heap *heap, struct ion_buffer *buffer);
119 void * (*map_kernel)(struct ion_heap *heap, struct ion_buffer *buffer);
120 void (*unmap_kernel)(struct ion_heap *heap, struct ion_buffer *buffer);
121 int (*map_user)(struct ion_heap *mapper, struct ion_buffer *buffer,
122 struct vm_area_struct *vma);
123 int (*shrink)(struct ion_heap *heap, gfp_t gfp_mask, int nr_to_scan);
127 * heap flags - flags between the heaps and core ion code
129 #define ION_HEAP_FLAG_DEFER_FREE (1 << 0)
132 * private flags - flags internal to ion
135 * Buffer is being freed from a shrinker function. Skip any possible
136 * heap-specific caching mechanism (e.g. page pools). Guarantees that
137 * any buffer storage that came from the system allocator will be
138 * returned to the system allocator.
140 #define ION_PRIV_FLAG_SHRINKER_FREE (1 << 0)
143 * struct ion_heap - represents a heap in the system
144 * @node: rb node to put the heap on the device's tree of heaps
145 * @dev: back pointer to the ion_device
146 * @type: type of heap
147 * @ops: ops struct as above
149 * @id: id of heap, also indicates priority of this heap when
150 * allocating. These are specified by platform data and
152 * @name: used for debugging
153 * @shrinker: a shrinker for the heap
154 * @free_list: free list head if deferred free is used
155 * @free_list_size size of the deferred free list in bytes
156 * @lock: protects the free list
157 * @waitqueue: queue to wait on from deferred free thread
158 * @task: task struct of deferred free thread
159 * @debug_show: called when heap debug file is read to add any
160 * heap specific debug info to output
162 * Represents a pool of memory from which buffers can be made. In some
163 * systems the only heap is regular system memory allocated via vmalloc.
164 * On others, some blocks might require large physically contiguous buffers
165 * that are allocated from a specially reserved heap.
168 struct plist_node node;
169 struct ion_device *dev;
170 enum ion_heap_type type;
171 struct ion_heap_ops *ops;
175 struct shrinker shrinker;
176 struct list_head free_list;
177 size_t free_list_size;
178 spinlock_t free_lock;
179 wait_queue_head_t waitqueue;
180 struct task_struct *task;
182 int (*debug_show)(struct ion_heap *heap, struct seq_file *, void *);
186 * ion_buffer_cached - this ion buffer is cached
189 * indicates whether this ion buffer is cached
191 bool ion_buffer_cached(struct ion_buffer *buffer);
194 * ion_buffer_fault_user_mappings - fault in user mappings of this buffer
197 * indicates whether userspace mappings of this buffer will be faulted
198 * in, this can affect how buffers are allocated from the heap.
200 bool ion_buffer_fault_user_mappings(struct ion_buffer *buffer);
203 * ion_device_create - allocates and returns an ion device
204 * @custom_ioctl: arch specific ioctl function if applicable
206 * returns a valid device or -PTR_ERR
208 struct ion_device *ion_device_create(long (*custom_ioctl)
209 (struct ion_client *client,
214 * ion_device_destroy - free and device and it's resource
217 void ion_device_destroy(struct ion_device *dev);
220 * ion_device_add_heap - adds a heap to the ion device
222 * @heap: the heap to add
224 void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap);
227 * some helpers for common operations on buffers using the sg_table
230 void *ion_heap_map_kernel(struct ion_heap *, struct ion_buffer *);
231 void ion_heap_unmap_kernel(struct ion_heap *, struct ion_buffer *);
232 int ion_heap_map_user(struct ion_heap *, struct ion_buffer *,
233 struct vm_area_struct *);
234 int ion_heap_buffer_zero(struct ion_buffer *buffer);
235 int ion_heap_pages_zero(struct page *page, size_t size, pgprot_t pgprot);
238 * ion_heap_init_shrinker
241 * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag or defines the shrink op
242 * this function will be called to setup a shrinker to shrink the freelists
243 * and call the heap's shrink op.
245 void ion_heap_init_shrinker(struct ion_heap *heap);
248 * ion_heap_init_deferred_free -- initialize deferred free functionality
251 * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag this function will
252 * be called to setup deferred frees. Calls to free the buffer will
253 * return immediately and the actual free will occur some time later
255 int ion_heap_init_deferred_free(struct ion_heap *heap);
258 * ion_heap_freelist_add - add a buffer to the deferred free list
260 * @buffer: the buffer
262 * Adds an item to the deferred freelist.
264 void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer *buffer);
267 * ion_heap_freelist_drain - drain the deferred free list
269 * @size: amount of memory to drain in bytes
271 * Drains the indicated amount of memory from the deferred freelist immediately.
272 * Returns the total amount freed. The total freed may be higher depending
273 * on the size of the items in the list, or lower if there is insufficient
274 * total memory on the freelist.
276 size_t ion_heap_freelist_drain(struct ion_heap *heap, size_t size);
279 * ion_heap_freelist_shrink - drain the deferred free
280 * list, skipping any heap-specific
281 * pooling or caching mechanisms
284 * @size: amount of memory to drain in bytes
286 * Drains the indicated amount of memory from the deferred freelist immediately.
287 * Returns the total amount freed. The total freed may be higher depending
288 * on the size of the items in the list, or lower if there is insufficient
289 * total memory on the freelist.
291 * Unlike with @ion_heap_freelist_drain, don't put any pages back into
292 * page pools or otherwise cache the pages. Everything must be
293 * genuinely free'd back to the system. If you're free'ing from a
294 * shrinker you probably want to use this. Note that this relies on
295 * the heap.ops.free callback honoring the ION_PRIV_FLAG_SHRINKER_FREE
298 size_t ion_heap_freelist_shrink(struct ion_heap *heap,
302 * ion_heap_freelist_size - returns the size of the freelist in bytes
305 size_t ion_heap_freelist_size(struct ion_heap *heap);
309 * functions for creating and destroying the built in ion heaps.
310 * architectures can add their own custom architecture specific
311 * heaps as appropriate.
314 struct ion_heap *ion_heap_create(struct ion_platform_heap *);
315 void ion_heap_destroy(struct ion_heap *);
316 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *);
317 void ion_system_heap_destroy(struct ion_heap *);
319 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *);
320 void ion_system_contig_heap_destroy(struct ion_heap *);
322 struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *);
323 void ion_carveout_heap_destroy(struct ion_heap *);
325 struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *);
326 void ion_chunk_heap_destroy(struct ion_heap *);
327 struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *);
328 void ion_cma_heap_destroy(struct ion_heap *);
331 * kernel api to allocate/free from carveout -- used when carveout is
332 * used to back an architecture specific custom heap
334 ion_phys_addr_t ion_carveout_allocate(struct ion_heap *heap, unsigned long size,
335 unsigned long align);
336 void ion_carveout_free(struct ion_heap *heap, ion_phys_addr_t addr,
339 * The carveout heap returns physical addresses, since 0 may be a valid
340 * physical address, this is used to indicate allocation failed
342 #define ION_CARVEOUT_ALLOCATE_FAIL -1
345 * functions for creating and destroying a heap pool -- allows you
346 * to keep a pool of pre allocated memory to use from your heap. Keeping
347 * a pool of memory that is ready for dma, ie any cached mapping have been
348 * invalidated from the cache, provides a significant performance benefit on
353 * struct ion_page_pool - pagepool struct
354 * @high_count: number of highmem items in the pool
355 * @low_count: number of lowmem items in the pool
356 * @high_items: list of highmem items
357 * @low_items: list of lowmem items
358 * @mutex: lock protecting this struct and especially the count
360 * @gfp_mask: gfp_mask to use from alloc
361 * @order: order of pages in the pool
362 * @list: plist node for list of pools
364 * Allows you to keep a pool of pre allocated pages to use from your heap.
365 * Keeping a pool of pages that is ready for dma, ie any cached mapping have
366 * been invalidated from the cache, provides a significant performance benefit
369 struct ion_page_pool {
372 struct list_head high_items;
373 struct list_head low_items;
377 struct plist_node list;
380 struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order);
381 void ion_page_pool_destroy(struct ion_page_pool *);
382 struct page *ion_page_pool_alloc(struct ion_page_pool *);
383 void ion_page_pool_free(struct ion_page_pool *, struct page *);
385 /** ion_page_pool_shrink - shrinks the size of the memory cached in the pool
387 * @gfp_mask: the memory type to reclaim
388 * @nr_to_scan: number of items to shrink in pages
390 * returns the number of items freed in pages
392 int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
396 * ion_pages_sync_for_device - cache flush pages for use with the specified
398 * @dev: the device the pages will be used with
399 * @page: the first page to be flushed
400 * @size: size in bytes of region to be flushed
401 * @dir: direction of dma transfer
403 void ion_pages_sync_for_device(struct device *dev, struct page *page,
404 size_t size, enum dma_data_direction dir);
406 #endif /* _ION_PRIV_H */