1/* 2 * drivers/staging/android/ion/ion_priv.h 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#ifndef _ION_PRIV_H 18#define _ION_PRIV_H 19 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> 30 31#include "ion.h" 32 33/** 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 43 * a void * 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 57*/ 58struct ion_buffer { 59 struct kref ref; 60 union { 61 struct rb_node node; 62 struct list_head list; 63 }; 64 struct ion_device *dev; 65 struct ion_heap *heap; 66 unsigned long flags; 67 unsigned long private_flags; 68 size_t size; 69 void *priv_virt; 70 struct mutex lock; 71 int kmap_cnt; 72 void *vaddr; 73 int dmap_cnt; 74 struct sg_table *sg_table; 75 struct page **pages; 76 struct list_head vmas; 77 /* used to track orphaned buffers */ 78 int handle_count; 79 char task_comm[TASK_COMM_LEN]; 80 pid_t pid; 81}; 82void ion_buffer_destroy(struct ion_buffer *buffer); 83 84/** 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 92 */ 93struct ion_device { 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, 100 unsigned long arg); 101 struct rb_root clients; 102 struct dentry *debug_root; 103 struct dentry *heaps_debug_root; 104 struct dentry *clients_debug_root; 105 int heap_cnt; 106}; 107 108/** 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 119 * 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. 123 */ 124struct ion_client { 125 struct rb_node node; 126 struct ion_device *dev; 127 struct rb_root handles; 128 struct idr idr; 129 struct mutex lock; 130 const char *name; 131 char *display_name; 132 int display_serial; 133 struct task_struct *task; 134 pid_t pid; 135 struct dentry *debug_root; 136}; 137 138/** 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 146 * 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. 149 */ 150struct ion_handle { 151 struct kref ref; 152 struct ion_client *client; 153 struct ion_buffer *buffer; 154 struct rb_node node; 155 unsigned int kmap_cnt; 156 int id; 157}; 158 159/** 160 * struct ion_heap_ops - ops to operate on a given heap 161 * @allocate: allocate memory 162 * @free: free memory 163 * @map_kernel map memory to the kernel 164 * @unmap_kernel unmap memory to the kernel 165 * @map_user map memory to userspace 166 * 167 * allocate, phys, and map_user return 0 on success, -errno on error. 168 * map_dma and map_kernel return pointer on success, ERR_PTR on 169 * error. @free will be called with ION_PRIV_FLAG_SHRINKER_FREE set in 170 * the buffer's private_flags when called from a shrinker. In that 171 * case, the pages being free'd must be truly free'd back to the 172 * system, not put in a page pool or otherwise cached. 173 */ 174struct ion_heap_ops { 175 int (*allocate)(struct ion_heap *heap, 176 struct ion_buffer *buffer, unsigned long len, 177 unsigned long align, unsigned long flags); 178 void (*free)(struct ion_buffer *buffer); 179 void * (*map_kernel)(struct ion_heap *heap, struct ion_buffer *buffer); 180 void (*unmap_kernel)(struct ion_heap *heap, struct ion_buffer *buffer); 181 int (*map_user)(struct ion_heap *mapper, struct ion_buffer *buffer, 182 struct vm_area_struct *vma); 183 int (*shrink)(struct ion_heap *heap, gfp_t gfp_mask, int nr_to_scan); 184}; 185 186/** 187 * heap flags - flags between the heaps and core ion code 188 */ 189#define ION_HEAP_FLAG_DEFER_FREE (1 << 0) 190 191/** 192 * private flags - flags internal to ion 193 */ 194/* 195 * Buffer is being freed from a shrinker function. Skip any possible 196 * heap-specific caching mechanism (e.g. page pools). Guarantees that 197 * any buffer storage that came from the system allocator will be 198 * returned to the system allocator. 199 */ 200#define ION_PRIV_FLAG_SHRINKER_FREE (1 << 0) 201 202/** 203 * struct ion_heap - represents a heap in the system 204 * @node: rb node to put the heap on the device's tree of heaps 205 * @dev: back pointer to the ion_device 206 * @type: type of heap 207 * @ops: ops struct as above 208 * @flags: flags 209 * @id: id of heap, also indicates priority of this heap when 210 * allocating. These are specified by platform data and 211 * MUST be unique 212 * @name: used for debugging 213 * @shrinker: a shrinker for the heap 214 * @free_list: free list head if deferred free is used 215 * @free_list_size size of the deferred free list in bytes 216 * @lock: protects the free list 217 * @waitqueue: queue to wait on from deferred free thread 218 * @task: task struct of deferred free thread 219 * @debug_show: called when heap debug file is read to add any 220 * heap specific debug info to output 221 * 222 * Represents a pool of memory from which buffers can be made. In some 223 * systems the only heap is regular system memory allocated via vmalloc. 224 * On others, some blocks might require large physically contiguous buffers 225 * that are allocated from a specially reserved heap. 226 */ 227struct ion_heap { 228 struct plist_node node; 229 struct ion_device *dev; 230 enum ion_heap_type type; 231 struct ion_heap_ops *ops; 232 unsigned long flags; 233 unsigned int id; 234 const char *name; 235 struct shrinker shrinker; 236 struct list_head free_list; 237 size_t free_list_size; 238 spinlock_t free_lock; 239 wait_queue_head_t waitqueue; 240 struct task_struct *task; 241 242 int (*debug_show)(struct ion_heap *heap, struct seq_file *, void *); 243}; 244 245/** 246 * ion_buffer_cached - this ion buffer is cached 247 * @buffer: buffer 248 * 249 * indicates whether this ion buffer is cached 250 */ 251bool ion_buffer_cached(struct ion_buffer *buffer); 252 253/** 254 * ion_buffer_fault_user_mappings - fault in user mappings of this buffer 255 * @buffer: buffer 256 * 257 * indicates whether userspace mappings of this buffer will be faulted 258 * in, this can affect how buffers are allocated from the heap. 259 */ 260bool ion_buffer_fault_user_mappings(struct ion_buffer *buffer); 261 262/** 263 * ion_device_create - allocates and returns an ion device 264 * @custom_ioctl: arch specific ioctl function if applicable 265 * 266 * returns a valid device or -PTR_ERR 267 */ 268struct ion_device *ion_device_create(long (*custom_ioctl) 269 (struct ion_client *client, 270 unsigned int cmd, 271 unsigned long arg)); 272 273/** 274 * ion_device_destroy - free and device and it's resource 275 * @dev: the device 276 */ 277void ion_device_destroy(struct ion_device *dev); 278 279/** 280 * ion_device_add_heap - adds a heap to the ion device 281 * @dev: the device 282 * @heap: the heap to add 283 */ 284void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap); 285 286/** 287 * some helpers for common operations on buffers using the sg_table 288 * and vaddr fields 289 */ 290void *ion_heap_map_kernel(struct ion_heap *, struct ion_buffer *); 291void ion_heap_unmap_kernel(struct ion_heap *, struct ion_buffer *); 292int ion_heap_map_user(struct ion_heap *, struct ion_buffer *, 293 struct vm_area_struct *); 294int ion_heap_buffer_zero(struct ion_buffer *buffer); 295int ion_heap_pages_zero(struct page *page, size_t size, pgprot_t pgprot); 296 297/** 298 * ion_heap_init_shrinker 299 * @heap: the heap 300 * 301 * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag or defines the shrink op 302 * this function will be called to setup a shrinker to shrink the freelists 303 * and call the heap's shrink op. 304 */ 305void ion_heap_init_shrinker(struct ion_heap *heap); 306 307/** 308 * ion_heap_init_deferred_free -- initialize deferred free functionality 309 * @heap: the heap 310 * 311 * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag this function will 312 * be called to setup deferred frees. Calls to free the buffer will 313 * return immediately and the actual free will occur some time later 314 */ 315int ion_heap_init_deferred_free(struct ion_heap *heap); 316 317/** 318 * ion_heap_freelist_add - add a buffer to the deferred free list 319 * @heap: the heap 320 * @buffer: the buffer 321 * 322 * Adds an item to the deferred freelist. 323 */ 324void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer *buffer); 325 326/** 327 * ion_heap_freelist_drain - drain the deferred free list 328 * @heap: the heap 329 * @size: amount of memory to drain in bytes 330 * 331 * Drains the indicated amount of memory from the deferred freelist immediately. 332 * Returns the total amount freed. The total freed may be higher depending 333 * on the size of the items in the list, or lower if there is insufficient 334 * total memory on the freelist. 335 */ 336size_t ion_heap_freelist_drain(struct ion_heap *heap, size_t size); 337 338/** 339 * ion_heap_freelist_shrink - drain the deferred free 340 * list, skipping any heap-specific 341 * pooling or caching mechanisms 342 * 343 * @heap: the heap 344 * @size: amount of memory to drain in bytes 345 * 346 * Drains the indicated amount of memory from the deferred freelist immediately. 347 * Returns the total amount freed. The total freed may be higher depending 348 * on the size of the items in the list, or lower if there is insufficient 349 * total memory on the freelist. 350 * 351 * Unlike with @ion_heap_freelist_drain, don't put any pages back into 352 * page pools or otherwise cache the pages. Everything must be 353 * genuinely free'd back to the system. If you're free'ing from a 354 * shrinker you probably want to use this. Note that this relies on 355 * the heap.ops.free callback honoring the ION_PRIV_FLAG_SHRINKER_FREE 356 * flag. 357 */ 358size_t ion_heap_freelist_shrink(struct ion_heap *heap, 359 size_t size); 360 361/** 362 * ion_heap_freelist_size - returns the size of the freelist in bytes 363 * @heap: the heap 364 */ 365size_t ion_heap_freelist_size(struct ion_heap *heap); 366 367 368/** 369 * functions for creating and destroying the built in ion heaps. 370 * architectures can add their own custom architecture specific 371 * heaps as appropriate. 372 */ 373 374struct ion_heap *ion_heap_create(struct ion_platform_heap *); 375void ion_heap_destroy(struct ion_heap *); 376struct ion_heap *ion_system_heap_create(struct ion_platform_heap *); 377void ion_system_heap_destroy(struct ion_heap *); 378 379struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *); 380void ion_system_contig_heap_destroy(struct ion_heap *); 381 382struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *); 383void ion_carveout_heap_destroy(struct ion_heap *); 384 385struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *); 386void ion_chunk_heap_destroy(struct ion_heap *); 387struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *); 388void ion_cma_heap_destroy(struct ion_heap *); 389 390/** 391 * functions for creating and destroying a heap pool -- allows you 392 * to keep a pool of pre allocated memory to use from your heap. Keeping 393 * a pool of memory that is ready for dma, ie any cached mapping have been 394 * invalidated from the cache, provides a significant performance benefit on 395 * many systems 396 */ 397 398/** 399 * struct ion_page_pool - pagepool struct 400 * @high_count: number of highmem items in the pool 401 * @low_count: number of lowmem items in the pool 402 * @high_items: list of highmem items 403 * @low_items: list of lowmem items 404 * @mutex: lock protecting this struct and especially the count 405 * item list 406 * @gfp_mask: gfp_mask to use from alloc 407 * @order: order of pages in the pool 408 * @list: plist node for list of pools 409 * @cached: it's cached pool or not 410 * 411 * Allows you to keep a pool of pre allocated pages to use from your heap. 412 * Keeping a pool of pages that is ready for dma, ie any cached mapping have 413 * been invalidated from the cache, provides a significant performance benefit 414 * on many systems 415 */ 416struct ion_page_pool { 417 int high_count; 418 int low_count; 419 bool cached; 420 struct list_head high_items; 421 struct list_head low_items; 422 struct mutex mutex; 423 gfp_t gfp_mask; 424 unsigned int order; 425 struct plist_node list; 426}; 427 428struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order, 429 bool cached); 430void ion_page_pool_destroy(struct ion_page_pool *); 431struct page *ion_page_pool_alloc(struct ion_page_pool *); 432void ion_page_pool_free(struct ion_page_pool *, struct page *); 433 434/** ion_page_pool_shrink - shrinks the size of the memory cached in the pool 435 * @pool: the pool 436 * @gfp_mask: the memory type to reclaim 437 * @nr_to_scan: number of items to shrink in pages 438 * 439 * returns the number of items freed in pages 440 */ 441int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask, 442 int nr_to_scan); 443 444/** 445 * ion_pages_sync_for_device - cache flush pages for use with the specified 446 * device 447 * @dev: the device the pages will be used with 448 * @page: the first page to be flushed 449 * @size: size in bytes of region to be flushed 450 * @dir: direction of dma transfer 451 */ 452void ion_pages_sync_for_device(struct device *dev, struct page *page, 453 size_t size, enum dma_data_direction dir); 454 455long ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg); 456 457int ion_sync_for_device(struct ion_client *client, int fd); 458 459struct ion_handle *ion_handle_get_by_id_nolock(struct ion_client *client, 460 int id); 461 462void ion_free_nolock(struct ion_client *client, struct ion_handle *handle); 463 464int ion_handle_put_nolock(struct ion_handle *handle); 465 466struct ion_handle *ion_handle_get_by_id(struct ion_client *client, 467 int id); 468 469int ion_handle_put(struct ion_handle *handle); 470 471int ion_query_heaps(struct ion_client *client, struct ion_heap_query *query); 472 473#endif /* _ION_PRIV_H */ 474