drivers/staging/android/ion/ion_priv.h

   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/kref.h>
  21 #include <linux/mm_types.h>
  22 #include <linux/mutex.h>
  23 #include <linux/rbtree.h>
  24 #include <linux/sched.h>
  25 #include <linux/shrinker.h>
  26 #include <linux/types.h>
  27
  28 #include "ion.h"
  29
  30 struct ion_buffer *ion_handle_buffer(struct ion_handle *handle);
  31
  32 /**
  33  * struct ion_buffer - metadata for a particular buffer
  34  * @ref:                refernce count
  35  * @node:               node in the ion_device buffers tree
  36  * @dev:                back pointer to the ion_device
  37  * @heap:               back pointer to the heap the buffer came from
  38  * @flags:              buffer specific flags
  39  * @size:               size of the buffer
  40  * @priv_virt:          private data to the buffer representable as
  41  *                      a void *
  42  * @priv_phys:          private data to the buffer representable as
  43  *                      an ion_phys_addr_t (and someday a phys_addr_t)
  44  * @lock:               protects the buffers cnt fields
  45  * @kmap_cnt:           number of times the buffer is mapped to the kernel
  46  * @vaddr:              the kenrel 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 */
  58 struct 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         size_t size;
  68         union {
  69                 void *priv_virt;
  70                 ion_phys_addr_t priv_phys;
  71         };
  72         struct mutex lock;
  73         int kmap_cnt;
  74         void *vaddr;
  75         int dmap_cnt;
  76         struct sg_table *sg_table;
  77         struct page **pages;
  78         struct list_head vmas;
  79         /* used to track orphaned buffers */
  80         int handle_count;
  81         char task_comm[TASK_COMM_LEN];
  82         pid_t pid;
  83 };
  84 void ion_buffer_destroy(struct ion_buffer *buffer);
  85
  86 /**
  87  * struct ion_heap_ops - ops to operate on a given heap
  88  * @allocate:           allocate memory
  89  * @free:               free memory
  90  * @phys                get physical address of a buffer (only define on
  91  *                      physically contiguous heaps)
  92  * @map_dma             map the memory for dma to a scatterlist
  93  * @unmap_dma           unmap the memory for dma
  94  * @map_kernel          map memory to the kernel
  95  * @unmap_kernel        unmap memory to the kernel
  96  * @map_user            map memory to userspace
  97  */
  98 struct ion_heap_ops {
  99         int (*allocate) (struct ion_heap *heap,
 100                          struct ion_buffer *buffer, unsigned long len,
 101                          unsigned long align, unsigned long flags);
 102         void (*free) (struct ion_buffer *buffer);
 103         int (*phys) (struct ion_heap *heap, struct ion_buffer *buffer,
 104                      ion_phys_addr_t *addr, size_t *len);
 105         struct sg_table *(*map_dma) (struct ion_heap *heap,
 106                                         struct ion_buffer *buffer);
 107         void (*unmap_dma) (struct ion_heap *heap, struct ion_buffer *buffer);
 108         void * (*map_kernel) (struct ion_heap *heap, struct ion_buffer *buffer);
 109         void (*unmap_kernel) (struct ion_heap *heap, struct ion_buffer *buffer);
 110         int (*map_user) (struct ion_heap *mapper, struct ion_buffer *buffer,
 111                          struct vm_area_struct *vma);
 112 };
 113
 114 /**
 115  * heap flags - flags between the heaps and core ion code
 116  */
 117 #define ION_HEAP_FLAG_DEFER_FREE (1 << 0)
 118
 119 /**
 120  * struct ion_heap - represents a heap in the system
 121  * @node:               rb node to put the heap on the device's tree of heaps
 122  * @dev:                back pointer to the ion_device
 123  * @type:               type of heap
 124  * @ops:                ops struct as above
 125  * @flags:              flags
 126  * @id:                 id of heap, also indicates priority of this heap when
 127  *                      allocating.  These are specified by platform data and
 128  *                      MUST be unique
 129  * @name:               used for debugging
 130  * @shrinker:           a shrinker for the heap, if the heap caches system
 131  *                      memory, it must define a shrinker to return it on low
 132  *                      memory conditions, this includes system memory cached
 133  *                      in the deferred free lists for heaps that support it
 134  * @free_list:          free list head if deferred free is used
 135  * @free_list_size      size of the deferred free list in bytes
 136  * @lock:               protects the free list
 137  * @waitqueue:          queue to wait on from deferred free thread
 138  * @task:               task struct of deferred free thread
 139  * @debug_show:         called when heap debug file is read to add any
 140  *                      heap specific debug info to output
 141  *
 142  * Represents a pool of memory from which buffers can be made.  In some
 143  * systems the only heap is regular system memory allocated via vmalloc.
 144  * On others, some blocks might require large physically contiguous buffers
 145  * that are allocated from a specially reserved heap.
 146  */
 147 struct ion_heap {
 148         struct plist_node node;
 149         struct ion_device *dev;
 150         enum ion_heap_type type;
 151         struct ion_heap_ops *ops;
 152         unsigned long flags;
 153         unsigned int id;
 154         const char *name;
 155         struct shrinker shrinker;
 156         struct list_head free_list;
 157         size_t free_list_size;
 158         struct rt_mutex lock;
 159         wait_queue_head_t waitqueue;
 160         struct task_struct *task;
 161         int (*debug_show)(struct ion_heap *heap, struct seq_file *, void *);
 162 };
 163
 164 /**
 165  * ion_buffer_cached - this ion buffer is cached
 166  * @buffer:             buffer
 167  *
 168  * indicates whether this ion buffer is cached
 169  */
 170 bool ion_buffer_cached(struct ion_buffer *buffer);
 171
 172 /**
 173  * ion_buffer_fault_user_mappings - fault in user mappings of this buffer
 174  * @buffer:             buffer
 175  *
 176  * indicates whether userspace mappings of this buffer will be faulted
 177  * in, this can affect how buffers are allocated from the heap.
 178  */
 179 bool ion_buffer_fault_user_mappings(struct ion_buffer *buffer);
 180
 181 /**
 182  * ion_device_create - allocates and returns an ion device
 183  * @custom_ioctl:       arch specific ioctl function if applicable
 184  *
 185  * returns a valid device or -PTR_ERR
 186  */
 187 struct ion_device *ion_device_create(long (*custom_ioctl)
 188                                      (struct ion_client *client,
 189                                       unsigned int cmd,
 190                                       unsigned long arg));
 191
 192 /**
 193  * ion_device_destroy - free and device and it's resource
 194  * @dev:                the device
 195  */
 196 void ion_device_destroy(struct ion_device *dev);
 197
 198 /**
 199  * ion_device_add_heap - adds a heap to the ion device
 200  * @dev:                the device
 201  * @heap:               the heap to add
 202  */
 203 void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap);
 204
 205 /**
 206  * some helpers for common operations on buffers using the sg_table
 207  * and vaddr fields
 208  */
 209 void *ion_heap_map_kernel(struct ion_heap *, struct ion_buffer *);
 210 void ion_heap_unmap_kernel(struct ion_heap *, struct ion_buffer *);
 211 int ion_heap_map_user(struct ion_heap *, struct ion_buffer *,
 212                         struct vm_area_struct *);
 213 int ion_heap_buffer_zero(struct ion_buffer *buffer);
 214
 215 /**
 216  * ion_heap_alloc_pages - allocate pages from alloc_pages
 217  * @buffer:             the buffer to allocate for, used to extract the flags
 218  * @gfp_flags:          the gfp_t for the allocation
 219  * @order:              the order of the allocatoin
 220  *
 221  * This funciton allocations from alloc pages and also does any other
 222  * necessary operations based on the buffer->flags.  For buffers which
 223  * will be faulted in the pages are split using split_page
 224  */
 225 struct page *ion_heap_alloc_pages(struct ion_buffer *buffer, gfp_t gfp_flags,
 226                                   unsigned int order);
 227
 228 /**
 229  * ion_heap_init_deferred_free -- initialize deferred free functionality
 230  * @heap:               the heap
 231  *
 232  * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag this function will
 233  * be called to setup deferred frees. Calls to free the buffer will
 234  * return immediately and the actual free will occur some time later
 235  */
 236 int ion_heap_init_deferred_free(struct ion_heap *heap);
 237
 238 /**
 239  * ion_heap_freelist_add - add a buffer to the deferred free list
 240  * @heap:               the heap
 241  * @buffer:             the buffer
 242  *
 243  * Adds an item to the deferred freelist.
 244  */
 245 void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer *buffer);
 246
 247 /**
 248  * ion_heap_freelist_drain - drain the deferred free list
 249  * @heap:               the heap
 250  * @size:               ammount of memory to drain in bytes
 251  *
 252  * Drains the indicated amount of memory from the deferred freelist immediately.
 253  * Returns the total amount freed.  The total freed may be higher depending
 254  * on the size of the items in the list, or lower if there is insufficient
 255  * total memory on the freelist.
 256  */
 257 size_t ion_heap_freelist_drain(struct ion_heap *heap, size_t size);
 258
 259 /**
 260  * ion_heap_freelist_size - returns the size of the freelist in bytes
 261  * @heap:               the heap
 262  */
 263 size_t ion_heap_freelist_size(struct ion_heap *heap);
 264
 265
 266 /**
 267  * functions for creating and destroying the built in ion heaps.
 268  * architectures can add their own custom architecture specific
 269  * heaps as appropriate.
 270  */
 271
 272 struct ion_heap *ion_heap_create(struct ion_platform_heap *);
 273 void ion_heap_destroy(struct ion_heap *);
 274 struct ion_heap *ion_system_heap_create(struct ion_platform_heap *);
 275 void ion_system_heap_destroy(struct ion_heap *);
 276
 277 struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *);
 278 void ion_system_contig_heap_destroy(struct ion_heap *);
 279
 280 struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *);
 281 void ion_carveout_heap_destroy(struct ion_heap *);
 282
 283 struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *);
 284 void ion_chunk_heap_destroy(struct ion_heap *);
 285 struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *);
 286 void ion_cma_heap_destroy(struct ion_heap *);
 287
 288 /**
 289  * kernel api to allocate/free from carveout -- used when carveout is
 290  * used to back an architecture specific custom heap
 291  */
 292 ion_phys_addr_t ion_carveout_allocate(struct ion_heap *heap, unsigned long size,
 293                                       unsigned long align);
 294 void ion_carveout_free(struct ion_heap *heap, ion_phys_addr_t addr,
 295                        unsigned long size);
 296 /**
 297  * The carveout heap returns physical addresses, since 0 may be a valid
 298  * physical address, this is used to indicate allocation failed
 299  */
 300 #define ION_CARVEOUT_ALLOCATE_FAIL -1
 301
 302 /**
 303  * functions for creating and destroying a heap pool -- allows you
 304  * to keep a pool of pre allocated memory to use from your heap.  Keeping
 305  * a pool of memory that is ready for dma, ie any cached mapping have been
 306  * invalidated from the cache, provides a significant peformance benefit on
 307  * many systems */
 308
 309 /**
 310  * struct ion_page_pool - pagepool struct
 311  * @high_count:         number of highmem items in the pool
 312  * @low_count:          number of lowmem items in the pool
 313  * @high_items:         list of highmem items
 314  * @low_items:          list of lowmem items
 315  * @shrinker:           a shrinker for the items
 316  * @mutex:              lock protecting this struct and especially the count
 317  *                      item list
 318  * @alloc:              function to be used to allocate pageory when the pool
 319  *                      is empty
 320  * @free:               function to be used to free pageory back to the system
 321  *                      when the shrinker fires
 322  * @gfp_mask:           gfp_mask to use from alloc
 323  * @order:              order of pages in the pool
 324  * @list:               plist node for list of pools
 325  *
 326  * Allows you to keep a pool of pre allocated pages to use from your heap.
 327  * Keeping a pool of pages that is ready for dma, ie any cached mapping have
 328  * been invalidated from the cache, provides a significant peformance benefit
 329  * on many systems
 330  */
 331 struct ion_page_pool {
 332         int high_count;
 333         int low_count;
 334         struct list_head high_items;
 335         struct list_head low_items;
 336         struct mutex mutex;
 337         gfp_t gfp_mask;
 338         unsigned int order;
 339         struct plist_node list;
 340 };
 341
 342 struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order);
 343 void ion_page_pool_destroy(struct ion_page_pool *);
 344 void *ion_page_pool_alloc(struct ion_page_pool *);
 345 void ion_page_pool_free(struct ion_page_pool *, struct page *);
 346
 347 /** ion_page_pool_shrink - shrinks the size of the memory cached in the pool
 348  * @pool:               the pool
 349  * @gfp_mask:           the memory type to reclaim
 350  * @nr_to_scan:         number of items to shrink in pages
 351  *
 352  * returns the number of items freed in pages
 353  */
 354 int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
 355                           int nr_to_scan);
 356
 357 #endif /* _ION_PRIV_H */