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>
29 #include <linux/miscdevice.h>
34 * struct ion_buffer - metadata for a particular buffer
35 * @ref: reference count
36 * @node: node in the ion_device buffers tree
37 * @dev: back pointer to the ion_device
38 * @heap: back pointer to the heap the buffer came from
39 * @flags: buffer specific flags
40 * @private_flags: internal buffer specific flags
41 * @size: size of the buffer
42 * @priv_virt: private data to the buffer representable as
44 * @lock: protects the buffers cnt fields
45 * @kmap_cnt: number of times the buffer is mapped to the kernel
46 * @vaddr: the kernel mapping if kmap_cnt is not zero
47 * @dmap_cnt: number of times the buffer is mapped for dma
48 * @sg_table: the sg table for the buffer if dmap_cnt is not zero
49 * @pages: flat array of pages in the buffer -- used by fault
50 * handler and only valid for buffers that are faulted in
51 * @vmas: list of vma's mapping this buffer
52 * @handle_count: count of handles referencing this buffer
53 * @task_comm: taskcomm of last client to reference this buffer in a
54 * handle, used for debugging
55 * @pid: pid of last client to reference this buffer in a
56 * handle, used for debugging
62 struct list_head list;
64 struct ion_device *dev;
65 struct ion_heap *heap;
67 unsigned long private_flags;
74 struct sg_table *sg_table;
76 struct list_head vmas;
77 /* used to track orphaned buffers */
79 char task_comm[TASK_COMM_LEN];
82 void ion_buffer_destroy(struct ion_buffer *buffer);
85 * struct ion_device - the metadata of the ion device node
86 * @dev: the actual misc device
87 * @buffers: an rb tree of all the existing buffers
88 * @buffer_lock: lock protecting the tree of buffers
89 * @lock: rwsem protecting the tree of heaps and clients
90 * @heaps: list of all the heaps in the system
91 * @user_clients: list of all the clients created from userspace
94 struct miscdevice dev;
95 struct rb_root buffers;
96 struct mutex buffer_lock;
97 struct rw_semaphore lock;
98 struct plist_head heaps;
99 long (*custom_ioctl)(struct ion_client *client, unsigned int cmd,
101 struct rb_root clients;
102 struct dentry *debug_root;
103 struct dentry *heaps_debug_root;
104 struct dentry *clients_debug_root;
109 * struct ion_client - a process/hw block local address space
110 * @node: node in the tree of all clients
111 * @dev: backpointer to ion device
112 * @handles: an rb tree of all the handles in this client
113 * @idr: an idr space for allocating handle ids
114 * @lock: lock protecting the tree of handles
115 * @name: used for debugging
116 * @display_name: used for debugging (unique version of @name)
117 * @display_serial: used for debugging (to make display_name unique)
118 * @task: used for debugging
120 * A client represents a list of buffers this client may access.
121 * The mutex stored here is used to protect both handles tree
122 * as well as the handles themselves, and should be held while modifying either.
126 struct ion_device *dev;
127 struct rb_root handles;
133 struct task_struct *task;
135 struct dentry *debug_root;
139 * ion_handle - a client local reference to a buffer
140 * @ref: reference count
141 * @client: back pointer to the client the buffer resides in
142 * @buffer: pointer to the buffer
143 * @node: node in the client's handle rbtree
144 * @kmap_cnt: count of times this client has mapped to kernel
145 * @id: client-unique id allocated by client->idr
147 * Modifications to node, map_cnt or mapping should be protected by the
148 * lock in the client. Other fields are never changed after initialization.
152 unsigned int user_ref_count;
153 struct ion_client *client;
154 struct ion_buffer *buffer;
156 unsigned int kmap_cnt;
161 * struct ion_heap_ops - ops to operate on a given heap
162 * @allocate: allocate memory
164 * @map_kernel map memory to the kernel
165 * @unmap_kernel unmap memory to the kernel
166 * @map_user map memory to userspace
168 * allocate, phys, and map_user return 0 on success, -errno on error.
169 * map_dma and map_kernel return pointer on success, ERR_PTR on
170 * error. @free will be called with ION_PRIV_FLAG_SHRINKER_FREE set in
171 * the buffer's private_flags when called from a shrinker. In that
172 * case, the pages being free'd must be truly free'd back to the
173 * system, not put in a page pool or otherwise cached.
175 struct ion_heap_ops {
176 int (*allocate)(struct ion_heap *heap,
177 struct ion_buffer *buffer, unsigned long len,
178 unsigned long align, unsigned long flags);
179 void (*free)(struct ion_buffer *buffer);
180 void * (*map_kernel)(struct ion_heap *heap, struct ion_buffer *buffer);
181 void (*unmap_kernel)(struct ion_heap *heap, struct ion_buffer *buffer);
182 int (*map_user)(struct ion_heap *mapper, struct ion_buffer *buffer,
183 struct vm_area_struct *vma);
184 int (*shrink)(struct ion_heap *heap, gfp_t gfp_mask, int nr_to_scan);
188 * heap flags - flags between the heaps and core ion code
190 #define ION_HEAP_FLAG_DEFER_FREE (1 << 0)
193 * private flags - flags internal to ion
196 * Buffer is being freed from a shrinker function. Skip any possible
197 * heap-specific caching mechanism (e.g. page pools). Guarantees that
198 * any buffer storage that came from the system allocator will be
199 * returned to the system allocator.
201 #define ION_PRIV_FLAG_SHRINKER_FREE (1 << 0)
204 * struct ion_heap - represents a heap in the system
205 * @node: rb node to put the heap on the device's tree of heaps
206 * @dev: back pointer to the ion_device
207 * @type: type of heap
208 * @ops: ops struct as above
210 * @id: id of heap, also indicates priority of this heap when
211 * allocating. These are specified by platform data and
213 * @name: used for debugging
214 * @shrinker: a shrinker for the heap
215 * @free_list: free list head if deferred free is used
216 * @free_list_size size of the deferred free list in bytes
217 * @lock: protects the free list
218 * @waitqueue: queue to wait on from deferred free thread
219 * @task: task struct of deferred free thread
220 * @debug_show: called when heap debug file is read to add any
221 * heap specific debug info to output
223 * Represents a pool of memory from which buffers can be made. In some
224 * systems the only heap is regular system memory allocated via vmalloc.
225 * On others, some blocks might require large physically contiguous buffers
226 * that are allocated from a specially reserved heap.
229 struct plist_node node;
230 struct ion_device *dev;
231 enum ion_heap_type type;
232 struct ion_heap_ops *ops;
236 struct shrinker shrinker;
237 struct list_head free_list;
238 size_t free_list_size;
239 spinlock_t free_lock;
240 wait_queue_head_t waitqueue;
241 struct task_struct *task;
243 int (*debug_show)(struct ion_heap *heap, struct seq_file *, void *);
247 * ion_buffer_cached - this ion buffer is cached
250 * indicates whether this ion buffer is cached
252 bool ion_buffer_cached(struct ion_buffer *buffer);
255 * ion_buffer_fault_user_mappings - fault in user mappings of this buffer
258 * indicates whether userspace mappings of this buffer will be faulted
259 * in, this can affect how buffers are allocated from the heap.
261 bool ion_buffer_fault_user_mappings(struct ion_buffer *buffer);
264 * ion_device_create - allocates and returns an ion device
265 * @custom_ioctl: arch specific ioctl function if applicable
267 * returns a valid device or -PTR_ERR
269 struct ion_device *ion_device_create(long (*custom_ioctl)
270 (struct ion_client *client,
275 * ion_device_destroy - free and device and it's resource
278 void ion_device_destroy(struct ion_device *dev);
281 * ion_device_add_heap - adds a heap to the ion device
283 * @heap: the heap to add
285 void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap);
288 * some helpers for common operations on buffers using the sg_table
291 void *ion_heap_map_kernel(struct ion_heap *, struct ion_buffer *);
292 void ion_heap_unmap_kernel(struct ion_heap *, struct ion_buffer *);
293 int ion_heap_map_user(struct ion_heap *, struct ion_buffer *,
294 struct vm_area_struct *);
295 int ion_heap_buffer_zero(struct ion_buffer *buffer);
296 int ion_heap_pages_zero(struct page *page, size_t size, pgprot_t pgprot);
299 * ion_heap_init_shrinker
302 * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag or defines the shrink op
303 * this function will be called to setup a shrinker to shrink the freelists
304 * and call the heap's shrink op.
306 void ion_heap_init_shrinker(struct ion_heap *heap);
309 * ion_heap_init_deferred_free -- initialize deferred free functionality
312 * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag this function will
313 * be called to setup deferred frees. Calls to free the buffer will
314 * return immediately and the actual free will occur some time later
316 int ion_heap_init_deferred_free(struct ion_heap *heap);
319 * ion_heap_freelist_add - add a buffer to the deferred free list
321 * @buffer: the buffer
323 * Adds an item to the deferred freelist.
325 void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer *buffer);
328 * ion_heap_freelist_drain - drain the deferred free list
330 * @size: amount of memory to drain in bytes
332 * Drains the indicated amount of memory from the deferred freelist immediately.
333 * Returns the total amount freed. The total freed may be higher depending
334 * on the size of the items in the list, or lower if there is insufficient
335 * total memory on the freelist.
337 size_t ion_heap_freelist_drain(struct ion_heap *heap, size_t size);
340 * ion_heap_freelist_shrink - drain the deferred free
341 * list, skipping any heap-specific
342 * pooling or caching mechanisms
345 * @size: amount of memory to drain in bytes
347 * Drains the indicated amount of memory from the deferred freelist immediately.
348 * Returns the total amount freed. The total freed may be higher depending
349 * on the size of the items in the list, or lower if there is insufficient
350 * total memory on the freelist.
352 * Unlike with @ion_heap_freelist_drain, don't put any pages back into
353 * page pools or otherwise cache the pages. Everything must be
354 * genuinely free'd back to the system. If you're free'ing from a
355 * shrinker you probably want to use this. Note that this relies on
356 * the heap.ops.free callback honoring the ION_PRIV_FLAG_SHRINKER_FREE
359 size_t ion_heap_freelist_shrink(struct ion_heap *heap,
363 * ion_heap_freelist_size - returns the size of the freelist in bytes
366 size_t ion_heap_freelist_size(struct ion_heap *heap);
370 * functions for creating and destroying the built in ion heaps.
371 * architectures can add their own custom architecture specific
372 * heaps as appropriate.
375 struct ion_heap *ion_heap_create(struct ion_platform_heap *);
376 void ion_heap_destroy(struct ion_heap *);
377 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *);
378 void ion_system_heap_destroy(struct ion_heap *);
380 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *);
381 void ion_system_contig_heap_destroy(struct ion_heap *);
383 struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *);
384 void ion_carveout_heap_destroy(struct ion_heap *);
386 struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *);
387 void ion_chunk_heap_destroy(struct ion_heap *);
388 struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *);
389 void ion_cma_heap_destroy(struct ion_heap *);
392 * functions for creating and destroying a heap pool -- allows you
393 * to keep a pool of pre allocated memory to use from your heap. Keeping
394 * a pool of memory that is ready for dma, ie any cached mapping have been
395 * invalidated from the cache, provides a significant performance benefit on
400 * struct ion_page_pool - pagepool struct
401 * @high_count: number of highmem items in the pool
402 * @low_count: number of lowmem items in the pool
403 * @high_items: list of highmem items
404 * @low_items: list of lowmem items
405 * @mutex: lock protecting this struct and especially the count
407 * @gfp_mask: gfp_mask to use from alloc
408 * @order: order of pages in the pool
409 * @list: plist node for list of pools
410 * @cached: it's cached pool or not
412 * Allows you to keep a pool of pre allocated pages to use from your heap.
413 * Keeping a pool of pages that is ready for dma, ie any cached mapping have
414 * been invalidated from the cache, provides a significant performance benefit
417 struct ion_page_pool {
421 struct list_head high_items;
422 struct list_head low_items;
426 struct plist_node list;
429 struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order,
431 void ion_page_pool_destroy(struct ion_page_pool *);
432 struct page *ion_page_pool_alloc(struct ion_page_pool *);
433 void ion_page_pool_free(struct ion_page_pool *, struct page *);
435 /** ion_page_pool_shrink - shrinks the size of the memory cached in the pool
437 * @gfp_mask: the memory type to reclaim
438 * @nr_to_scan: number of items to shrink in pages
440 * returns the number of items freed in pages
442 int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
446 * ion_pages_sync_for_device - cache flush pages for use with the specified
448 * @dev: the device the pages will be used with
449 * @page: the first page to be flushed
450 * @size: size in bytes of region to be flushed
451 * @dir: direction of dma transfer
453 void ion_pages_sync_for_device(struct device *dev, struct page *page,
454 size_t size, enum dma_data_direction dir);
456 long ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
458 int ion_sync_for_device(struct ion_client *client, int fd);
460 struct ion_handle *ion_handle_get_by_id_nolock(struct ion_client *client,
463 bool ion_handle_validate(struct ion_client *client,
464 struct ion_handle *handle);
466 void ion_free_nolock(struct ion_client *client, struct ion_handle *handle);
468 int ion_handle_put_nolock(struct ion_handle *handle);
470 int ion_handle_put(struct ion_handle *handle);
472 int ion_query_heaps(struct ion_client *client, struct ion_heap_query *query);
474 int ion_share_dma_buf_fd_nolock(struct ion_client *client,
475 struct ion_handle *handle);
477 #endif /* _ION_PRIV_H */