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 * @lock: protects the buffers cnt fields
46 * @kmap_cnt: number of times the buffer is mapped to the kernel
47 * @vaddr: the kernel mapping if kmap_cnt is not zero
48 * @dmap_cnt: number of times the buffer is mapped for dma
49 * @sg_table: the sg table for the buffer if dmap_cnt is not zero
50 * @pages: flat array of pages in the buffer -- used by fault
51 * handler and only valid for buffers that are faulted in
52 * @vmas: list of vma's mapping this buffer
53 * @handle_count: count of handles referencing this buffer
54 * @task_comm: taskcomm of last client to reference this buffer in a
55 * handle, used for debugging
56 * @pid: pid of last client to reference this buffer in a
57 * handle, used for debugging
63 struct list_head list;
65 struct ion_device *dev;
66 struct ion_heap *heap;
68 unsigned long private_flags;
75 struct sg_table *sg_table;
77 struct list_head vmas;
78 /* used to track orphaned buffers */
80 char task_comm[TASK_COMM_LEN];
83 void ion_buffer_destroy(struct ion_buffer *buffer);
86 * struct ion_heap_ops - ops to operate on a given heap
87 * @allocate: allocate memory
89 * @map_dma map the memory for dma to a scatterlist
90 * @unmap_dma unmap the memory for dma
91 * @map_kernel map memory to the kernel
92 * @unmap_kernel unmap memory to the kernel
93 * @map_user map memory to userspace
95 * allocate, phys, and map_user return 0 on success, -errno on error.
96 * map_dma and map_kernel return pointer on success, ERR_PTR on
97 * error. @free will be called with ION_PRIV_FLAG_SHRINKER_FREE set in
98 * the buffer's private_flags when called from a shrinker. In that
99 * case, the pages being free'd must be truly free'd back to the
100 * system, not put in a page pool or otherwise cached.
102 struct ion_heap_ops {
103 int (*allocate)(struct ion_heap *heap,
104 struct ion_buffer *buffer, unsigned long len,
105 unsigned long align, unsigned long flags);
106 void (*free)(struct ion_buffer *buffer);
107 struct sg_table * (*map_dma)(struct ion_heap *heap,
108 struct ion_buffer *buffer);
109 void (*unmap_dma)(struct ion_heap *heap, struct ion_buffer *buffer);
110 void * (*map_kernel)(struct ion_heap *heap, struct ion_buffer *buffer);
111 void (*unmap_kernel)(struct ion_heap *heap, struct ion_buffer *buffer);
112 int (*map_user)(struct ion_heap *mapper, struct ion_buffer *buffer,
113 struct vm_area_struct *vma);
114 int (*shrink)(struct ion_heap *heap, gfp_t gfp_mask, int nr_to_scan);
118 * heap flags - flags between the heaps and core ion code
120 #define ION_HEAP_FLAG_DEFER_FREE (1 << 0)
123 * private flags - flags internal to ion
126 * Buffer is being freed from a shrinker function. Skip any possible
127 * heap-specific caching mechanism (e.g. page pools). Guarantees that
128 * any buffer storage that came from the system allocator will be
129 * returned to the system allocator.
131 #define ION_PRIV_FLAG_SHRINKER_FREE (1 << 0)
134 * struct ion_heap - represents a heap in the system
135 * @node: rb node to put the heap on the device's tree of heaps
136 * @dev: back pointer to the ion_device
137 * @type: type of heap
138 * @ops: ops struct as above
140 * @id: id of heap, also indicates priority of this heap when
141 * allocating. These are specified by platform data and
143 * @name: used for debugging
144 * @shrinker: a shrinker for the heap
145 * @free_list: free list head if deferred free is used
146 * @free_list_size size of the deferred free list in bytes
147 * @lock: protects the free list
148 * @waitqueue: queue to wait on from deferred free thread
149 * @task: task struct of deferred free thread
150 * @debug_show: called when heap debug file is read to add any
151 * heap specific debug info to output
153 * Represents a pool of memory from which buffers can be made. In some
154 * systems the only heap is regular system memory allocated via vmalloc.
155 * On others, some blocks might require large physically contiguous buffers
156 * that are allocated from a specially reserved heap.
159 struct plist_node node;
160 struct ion_device *dev;
161 enum ion_heap_type type;
162 struct ion_heap_ops *ops;
166 struct shrinker shrinker;
167 struct list_head free_list;
168 size_t free_list_size;
169 spinlock_t free_lock;
170 wait_queue_head_t waitqueue;
171 struct task_struct *task;
173 int (*debug_show)(struct ion_heap *heap, struct seq_file *, void *);
177 * ion_buffer_cached - this ion buffer is cached
180 * indicates whether this ion buffer is cached
182 bool ion_buffer_cached(struct ion_buffer *buffer);
185 * ion_buffer_fault_user_mappings - fault in user mappings of this buffer
188 * indicates whether userspace mappings of this buffer will be faulted
189 * in, this can affect how buffers are allocated from the heap.
191 bool ion_buffer_fault_user_mappings(struct ion_buffer *buffer);
194 * ion_device_create - allocates and returns an ion device
195 * @custom_ioctl: arch specific ioctl function if applicable
197 * returns a valid device or -PTR_ERR
199 struct ion_device *ion_device_create(long (*custom_ioctl)
200 (struct ion_client *client,
205 * ion_device_destroy - free and device and it's resource
208 void ion_device_destroy(struct ion_device *dev);
211 * ion_device_add_heap - adds a heap to the ion device
213 * @heap: the heap to add
215 void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap);
218 * some helpers for common operations on buffers using the sg_table
221 void *ion_heap_map_kernel(struct ion_heap *, struct ion_buffer *);
222 void ion_heap_unmap_kernel(struct ion_heap *, struct ion_buffer *);
223 int ion_heap_map_user(struct ion_heap *, struct ion_buffer *,
224 struct vm_area_struct *);
225 int ion_heap_buffer_zero(struct ion_buffer *buffer);
226 int ion_heap_pages_zero(struct page *page, size_t size, pgprot_t pgprot);
229 * ion_heap_init_shrinker
232 * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag or defines the shrink op
233 * this function will be called to setup a shrinker to shrink the freelists
234 * and call the heap's shrink op.
236 void ion_heap_init_shrinker(struct ion_heap *heap);
239 * ion_heap_init_deferred_free -- initialize deferred free functionality
242 * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag this function will
243 * be called to setup deferred frees. Calls to free the buffer will
244 * return immediately and the actual free will occur some time later
246 int ion_heap_init_deferred_free(struct ion_heap *heap);
249 * ion_heap_freelist_add - add a buffer to the deferred free list
251 * @buffer: the buffer
253 * Adds an item to the deferred freelist.
255 void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer *buffer);
258 * ion_heap_freelist_drain - drain the deferred free list
260 * @size: amount of memory to drain in bytes
262 * Drains the indicated amount of memory from the deferred freelist immediately.
263 * Returns the total amount freed. The total freed may be higher depending
264 * on the size of the items in the list, or lower if there is insufficient
265 * total memory on the freelist.
267 size_t ion_heap_freelist_drain(struct ion_heap *heap, size_t size);
270 * ion_heap_freelist_shrink - drain the deferred free
271 * list, skipping any heap-specific
272 * pooling or caching mechanisms
275 * @size: amount of memory to drain in bytes
277 * Drains the indicated amount of memory from the deferred freelist immediately.
278 * Returns the total amount freed. The total freed may be higher depending
279 * on the size of the items in the list, or lower if there is insufficient
280 * total memory on the freelist.
282 * Unlike with @ion_heap_freelist_drain, don't put any pages back into
283 * page pools or otherwise cache the pages. Everything must be
284 * genuinely free'd back to the system. If you're free'ing from a
285 * shrinker you probably want to use this. Note that this relies on
286 * the heap.ops.free callback honoring the ION_PRIV_FLAG_SHRINKER_FREE
289 size_t ion_heap_freelist_shrink(struct ion_heap *heap,
293 * ion_heap_freelist_size - returns the size of the freelist in bytes
296 size_t ion_heap_freelist_size(struct ion_heap *heap);
300 * functions for creating and destroying the built in ion heaps.
301 * architectures can add their own custom architecture specific
302 * heaps as appropriate.
305 struct ion_heap *ion_heap_create(struct ion_platform_heap *);
306 void ion_heap_destroy(struct ion_heap *);
307 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *);
308 void ion_system_heap_destroy(struct ion_heap *);
310 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *);
311 void ion_system_contig_heap_destroy(struct ion_heap *);
313 struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *);
314 void ion_carveout_heap_destroy(struct ion_heap *);
316 struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *);
317 void ion_chunk_heap_destroy(struct ion_heap *);
318 struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *);
319 void ion_cma_heap_destroy(struct ion_heap *);
322 * kernel api to allocate/free from carveout -- used when carveout is
323 * used to back an architecture specific custom heap
325 ion_phys_addr_t ion_carveout_allocate(struct ion_heap *heap, unsigned long size,
326 unsigned long align);
327 void ion_carveout_free(struct ion_heap *heap, ion_phys_addr_t addr,
330 * The carveout heap returns physical addresses, since 0 may be a valid
331 * physical address, this is used to indicate allocation failed
333 #define ION_CARVEOUT_ALLOCATE_FAIL -1
336 * functions for creating and destroying a heap pool -- allows you
337 * to keep a pool of pre allocated memory to use from your heap. Keeping
338 * a pool of memory that is ready for dma, ie any cached mapping have been
339 * invalidated from the cache, provides a significant performance benefit on
344 * struct ion_page_pool - pagepool struct
345 * @high_count: number of highmem items in the pool
346 * @low_count: number of lowmem items in the pool
347 * @high_items: list of highmem items
348 * @low_items: list of lowmem items
349 * @mutex: lock protecting this struct and especially the count
351 * @gfp_mask: gfp_mask to use from alloc
352 * @order: order of pages in the pool
353 * @list: plist node for list of pools
355 * Allows you to keep a pool of pre allocated pages to use from your heap.
356 * Keeping a pool of pages that is ready for dma, ie any cached mapping have
357 * been invalidated from the cache, provides a significant performance benefit
360 struct ion_page_pool {
363 struct list_head high_items;
364 struct list_head low_items;
368 struct plist_node list;
371 struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order);
372 void ion_page_pool_destroy(struct ion_page_pool *);
373 struct page *ion_page_pool_alloc(struct ion_page_pool *);
374 void ion_page_pool_free(struct ion_page_pool *, struct page *);
376 /** ion_page_pool_shrink - shrinks the size of the memory cached in the pool
378 * @gfp_mask: the memory type to reclaim
379 * @nr_to_scan: number of items to shrink in pages
381 * returns the number of items freed in pages
383 int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
387 * ion_pages_sync_for_device - cache flush pages for use with the specified
389 * @dev: the device the pages will be used with
390 * @page: the first page to be flushed
391 * @size: size in bytes of region to be flushed
392 * @dir: direction of dma transfer
394 void ion_pages_sync_for_device(struct device *dev, struct page *page,
395 size_t size, enum dma_data_direction dir);
397 #endif /* _ION_PRIV_H */