/* SPDX-License-Identifier: GPL-2.0 */ /* * drivers/staging/android/ion/ion.h * * Copyright (C) 2011 Google, Inc. */ #ifndef _ION_H #define _ION_H #include #include #include #include #include #include #include #include #include #include #include "../uapi/ion.h" /** * struct ion_platform_heap - defines a heap in the given platform * @type: type of the heap from ion_heap_type enum * @id: unique identifier for heap. When allocating higher numb ers * will be allocated from first. At allocation these are passed * as a bit mask and therefore can not exceed ION_NUM_HEAP_IDS. * @name: used for debug purposes * @base: base address of heap in physical memory if applicable * @size: size of the heap in bytes if applicable * @priv: private info passed from the board file * * Provided by the board file. */ struct ion_platform_heap { enum ion_heap_type type; unsigned int id; const char *name; phys_addr_t base; size_t size; phys_addr_t align; void *priv; }; /** * struct ion_buffer - metadata for a particular buffer * @ref: reference count * @node: node in the ion_device buffers tree * @dev: back pointer to the ion_device * @heap: back pointer to the heap the buffer came from * @flags: buffer specific flags * @private_flags: internal buffer specific flags * @size: size of the buffer * @priv_virt: private data to the buffer representable as * a void * * @lock: protects the buffers cnt fields * @kmap_cnt: number of times the buffer is mapped to the kernel * @vaddr: the kernel mapping if kmap_cnt is not zero * @sg_table: the sg table for the buffer if dmap_cnt is not zero */ struct ion_buffer { union { struct rb_node node; struct list_head list; }; struct ion_device *dev; struct ion_heap *heap; unsigned long flags; unsigned long private_flags; size_t size; void *priv_virt; struct mutex lock; int kmap_cnt; void *vaddr; struct sg_table *sg_table; struct list_head attachments; }; void ion_buffer_destroy(struct ion_buffer *buffer); /** * struct ion_device - the metadata of the ion device node * @dev: the actual misc device * @buffers: an rb tree of all the existing buffers * @buffer_lock: lock protecting the tree of buffers * @lock: rwsem protecting the tree of heaps and clients */ struct ion_device { struct miscdevice dev; struct rb_root buffers; struct mutex buffer_lock; struct rw_semaphore lock; struct plist_head heaps; struct dentry *debug_root; int heap_cnt; }; /** * struct ion_heap_ops - ops to operate on a given heap * @allocate: allocate memory * @free: free memory * @map_kernel map memory to the kernel * @unmap_kernel unmap memory to the kernel * @map_user map memory to userspace * * allocate, phys, and map_user return 0 on success, -errno on error. * map_dma and map_kernel return pointer on success, ERR_PTR on * error. @free will be called with ION_PRIV_FLAG_SHRINKER_FREE set in * the buffer's private_flags when called from a shrinker. In that * case, the pages being free'd must be truly free'd back to the * system, not put in a page pool or otherwise cached. */ struct ion_heap_ops { int (*allocate)(struct ion_heap *heap, struct ion_buffer *buffer, unsigned long len, unsigned long flags); void (*free)(struct ion_buffer *buffer); void * (*map_kernel)(struct ion_heap *heap, struct ion_buffer *buffer); void (*unmap_kernel)(struct ion_heap *heap, struct ion_buffer *buffer); int (*map_user)(struct ion_heap *mapper, struct ion_buffer *buffer, struct vm_area_struct *vma); int (*shrink)(struct ion_heap *heap, gfp_t gfp_mask, int nr_to_scan); }; /** * heap flags - flags between the heaps and core ion code */ #define ION_HEAP_FLAG_DEFER_FREE BIT(0) /** * private flags - flags internal to ion */ /* * Buffer is being freed from a shrinker function. Skip any possible * heap-specific caching mechanism (e.g. page pools). Guarantees that * any buffer storage that came from the system allocator will be * returned to the system allocator. */ #define ION_PRIV_FLAG_SHRINKER_FREE BIT(0) /** * struct ion_heap - represents a heap in the system * @node: rb node to put the heap on the device's tree of heaps * @dev: back pointer to the ion_device * @type: type of heap * @ops: ops struct as above * @flags: flags * @id: id of heap, also indicates priority of this heap when * allocating. These are specified by platform data and * MUST be unique * @name: used for debugging * @shrinker: a shrinker for the heap * @free_list: free list head if deferred free is used * @free_list_size size of the deferred free list in bytes * @lock: protects the free list * @waitqueue: queue to wait on from deferred free thread * @task: task struct of deferred free thread * @debug_show: called when heap debug file is read to add any * heap specific debug info to output * * Represents a pool of memory from which buffers can be made. In some * systems the only heap is regular system memory allocated via vmalloc. * On others, some blocks might require large physically contiguous buffers * that are allocated from a specially reserved heap. */ struct ion_heap { struct plist_node node; struct ion_device *dev; enum ion_heap_type type; struct ion_heap_ops *ops; unsigned long flags; unsigned int id; const char *name; struct shrinker shrinker; struct list_head free_list; size_t free_list_size; spinlock_t free_lock; wait_queue_head_t waitqueue; struct task_struct *task; int (*debug_show)(struct ion_heap *heap, struct seq_file *s, void *unused); }; /** * ion_device_add_heap - adds a heap to the ion device * @heap: the heap to add */ void ion_device_add_heap(struct ion_heap *heap); /** * some helpers for common operations on buffers using the sg_table * and vaddr fields */ void *ion_heap_map_kernel(struct ion_heap *heap, struct ion_buffer *buffer); void ion_heap_unmap_kernel(struct ion_heap *heap, struct ion_buffer *buffer); int ion_heap_map_user(struct ion_heap *heap, struct ion_buffer *buffer, struct vm_area_struct *vma); int ion_heap_buffer_zero(struct ion_buffer *buffer); int ion_heap_pages_zero(struct page *page, size_t size, pgprot_t pgprot); int ion_alloc(size_t len, unsigned int heap_id_mask, unsigned int flags); /** * ion_heap_init_shrinker * @heap: the heap * * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag or defines the shrink op * this function will be called to setup a shrinker to shrink the freelists * and call the heap's shrink op. */ int ion_heap_init_shrinker(struct ion_heap *heap); /** * ion_heap_init_deferred_free -- initialize deferred free functionality * @heap: the heap * * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag this function will * be called to setup deferred frees. Calls to free the buffer will * return immediately and the actual free will occur some time later */ int ion_heap_init_deferred_free(struct ion_heap *heap); /** * ion_heap_freelist_add - add a buffer to the deferred free list * @heap: the heap * @buffer: the buffer * * Adds an item to the deferred freelist. */ void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer *buffer); /** * ion_heap_freelist_drain - drain the deferred free list * @heap: the heap * @size: amount of memory to drain in bytes * * Drains the indicated amount of memory from the deferred freelist immediately. * Returns the total amount freed. The total freed may be higher depending * on the size of the items in the list, or lower if there is insufficient * total memory on the freelist. */ size_t ion_heap_freelist_drain(struct ion_heap *heap, size_t size); /** * ion_heap_freelist_shrink - drain the deferred free * list, skipping any heap-specific * pooling or caching mechanisms * * @heap: the heap * @size: amount of memory to drain in bytes * * Drains the indicated amount of memory from the deferred freelist immediately. * Returns the total amount freed. The total freed may be higher depending * on the size of the items in the list, or lower if there is insufficient * total memory on the freelist. * * Unlike with @ion_heap_freelist_drain, don't put any pages back into * page pools or otherwise cache the pages. Everything must be * genuinely free'd back to the system. If you're free'ing from a * shrinker you probably want to use this. Note that this relies on * the heap.ops.free callback honoring the ION_PRIV_FLAG_SHRINKER_FREE * flag. */ size_t ion_heap_freelist_shrink(struct ion_heap *heap, size_t size); /** * ion_heap_freelist_size - returns the size of the freelist in bytes * @heap: the heap */ size_t ion_heap_freelist_size(struct ion_heap *heap); /** * functions for creating and destroying a heap pool -- allows you * to keep a pool of pre allocated memory to use from your heap. Keeping * a pool of memory that is ready for dma, ie any cached mapping have been * invalidated from the cache, provides a significant performance benefit on * many systems */ /** * struct ion_page_pool - pagepool struct * @high_count: number of highmem items in the pool * @low_count: number of lowmem items in the pool * @high_items: list of highmem items * @low_items: list of lowmem items * @mutex: lock protecting this struct and especially the count * item list * @gfp_mask: gfp_mask to use from alloc * @order: order of pages in the pool * @list: plist node for list of pools * * Allows you to keep a pool of pre allocated pages to use from your heap. * Keeping a pool of pages that is ready for dma, ie any cached mapping have * been invalidated from the cache, provides a significant performance benefit * on many systems */ struct ion_page_pool { int high_count; int low_count; struct list_head high_items; struct list_head low_items; struct mutex mutex; gfp_t gfp_mask; unsigned int order; struct plist_node list; }; struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order); void ion_page_pool_destroy(struct ion_page_pool *pool); struct page *ion_page_pool_alloc(struct ion_page_pool *pool); void ion_page_pool_free(struct ion_page_pool *pool, struct page *page); /** ion_page_pool_shrink - shrinks the size of the memory cached in the pool * @pool: the pool * @gfp_mask: the memory type to reclaim * @nr_to_scan: number of items to shrink in pages * * returns the number of items freed in pages */ int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask, int nr_to_scan); long ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg); int ion_query_heaps(struct ion_heap_query *query); #endif /* _ION_H */