[linux-2.6-block.git] / drivers / android / binder_alloc.h

/*
 * Copyright (C) 2017 Google, Inc.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#ifndef _LINUX_BINDER_ALLOC_H
#define _LINUX_BINDER_ALLOC_H

#include <linux/rbtree.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/rtmutex.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/list_lru.h>

extern struct list_lru binder_alloc_lru;
struct binder_transaction;

/**
 * struct binder_buffer - buffer used for binder transactions
 * @entry:              entry alloc->buffers
 * @rb_node:            node for allocated_buffers/free_buffers rb trees
 * @free:               true if buffer is free
 * @allow_user_free:    describe the second member of struct blah,
 * @async_transaction:  describe the second member of struct blah,
 * @debug_id:           describe the second member of struct blah,
 * @transaction:        describe the second member of struct blah,
 * @target_node:        describe the second member of struct blah,
 * @data_size:          describe the second member of struct blah,
 * @offsets_size:       describe the second member of struct blah,
 * @extra_buffers_size: describe the second member of struct blah,
 * @data:i              describe the second member of struct blah,
 *
 * Bookkeeping structure for binder transaction buffers
 */
struct binder_buffer {
	struct list_head entry; /* free and allocated entries by address */
	struct rb_node rb_node; /* free entry by size or allocated entry */
				/* by address */
	unsigned free:1;
	unsigned allow_user_free:1;
	unsigned async_transaction:1;
	unsigned free_in_progress:1;
	unsigned debug_id:28;

	struct binder_transaction *transaction;

	struct binder_node *target_node;
	size_t data_size;
	size_t offsets_size;
	size_t extra_buffers_size;
	void *data;
};

/**
 * struct binder_lru_page - page object used for binder shrinker
 * @page_ptr: pointer to physical page in mmap'd space
 * @lru:      entry in binder_alloc_lru
 * @alloc:    binder_alloc for a proc
 */
struct binder_lru_page {
	struct list_head lru;
	struct page *page_ptr;
	struct binder_alloc *alloc;
};

/**
 * struct binder_alloc - per-binder proc state for binder allocator
 * @vma:                vm_area_struct passed to mmap_handler
 *                      (invarient after mmap)
 * @tsk:                tid for task that called init for this proc
 *                      (invariant after init)
 * @vma_vm_mm:          copy of vma->vm_mm (invarient after mmap)
 * @buffer:             base of per-proc address space mapped via mmap
 * @user_buffer_offset: offset between user and kernel VAs for buffer
 * @buffers:            list of all buffers for this proc
 * @free_buffers:       rb tree of buffers available for allocation
 *                      sorted by size
 * @allocated_buffers:  rb tree of allocated buffers sorted by address
 * @free_async_space:   VA space available for async buffers. This is
 *                      initialized at mmap time to 1/2 the full VA space
 * @pages:              array of binder_lru_page
 * @buffer_size:        size of address space specified via mmap
 * @pid:                pid for associated binder_proc (invariant after init)
 * @pages_high:         high watermark of offset in @pages
 *
 * Bookkeeping structure for per-proc address space management for binder
 * buffers. It is normally initialized during binder_init() and binder_mmap()
 * calls. The address space is used for both user-visible buffers and for
 * struct binder_buffer objects used to track the user buffers
 */
struct binder_alloc {
	struct mutex mutex;
	struct vm_area_struct *vma;
	struct mm_struct *vma_vm_mm;
	void *buffer;
	ptrdiff_t user_buffer_offset;
	struct list_head buffers;
	struct rb_root free_buffers;
	struct rb_root allocated_buffers;
	size_t free_async_space;
	struct binder_lru_page *pages;
	size_t buffer_size;
	uint32_t buffer_free;
	int pid;
	size_t pages_high;
};

#ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST
void binder_selftest_alloc(struct binder_alloc *alloc);
#else
static inline void binder_selftest_alloc(struct binder_alloc *alloc) {}
#endif
enum lru_status binder_alloc_free_page(struct list_head *item,
				       struct list_lru_one *lru,
				       spinlock_t *lock, void *cb_arg);
extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
						  size_t data_size,
						  size_t offsets_size,
						  size_t extra_buffers_size,
						  int is_async);
extern void binder_alloc_init(struct binder_alloc *alloc);
void binder_alloc_shrinker_init(void);
extern void binder_alloc_vma_close(struct binder_alloc *alloc);
extern struct binder_buffer *
binder_alloc_prepare_to_free(struct binder_alloc *alloc,
			     uintptr_t user_ptr);
extern void binder_alloc_free_buf(struct binder_alloc *alloc,
				  struct binder_buffer *buffer);
extern int binder_alloc_mmap_handler(struct binder_alloc *alloc,
				     struct vm_area_struct *vma);
extern void binder_alloc_deferred_release(struct binder_alloc *alloc);
extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc);
extern void binder_alloc_print_allocated(struct seq_file *m,
					 struct binder_alloc *alloc);
void binder_alloc_print_pages(struct seq_file *m,
			      struct binder_alloc *alloc);

/**
 * binder_alloc_get_free_async_space() - get free space available for async
 * @alloc:	binder_alloc for this proc
 *
 * Return:	the bytes remaining in the address-space for async transactions
 */
static inline size_t
binder_alloc_get_free_async_space(struct binder_alloc *alloc)
{
	size_t free_async_space;

	mutex_lock(&alloc->mutex);
	free_async_space = alloc->free_async_space;
	mutex_unlock(&alloc->mutex);
	return free_async_space;
}

/**
 * binder_alloc_get_user_buffer_offset() - get offset between kernel/user addrs
 * @alloc:	binder_alloc for this proc
 *
 * Return:	the offset between kernel and user-space addresses to use for
 * virtual address conversion
 */
static inline ptrdiff_t
binder_alloc_get_user_buffer_offset(struct binder_alloc *alloc)
{
	/*
	 * user_buffer_offset is constant if vma is set and
	 * undefined if vma is not set. It is possible to
	 * get here with !alloc->vma if the target process
	 * is dying while a transaction is being initiated.
	 * Returning the old value is ok in this case and
	 * the transaction will fail.
	 */
	return alloc->user_buffer_offset;
}

#endif /* _LINUX_BINDER_ALLOC_H */
Commit	Line	Data
0c972a05 TK	1	/*
	2	* Copyright (C) 2017 Google, Inc.
	3	*
	4	* This software is licensed under the terms of the GNU General Public
	5	* License version 2, as published by the Free Software Foundation, and
	6	* may be copied, distributed, and modified under those terms.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	*/
	14
	15	#ifndef _LINUX_BINDER_ALLOC_H
	16	#define _LINUX_BINDER_ALLOC_H
	17
	18	#include <linux/rbtree.h>
	19	#include <linux/list.h>
	20	#include <linux/mm.h>
	21	#include <linux/rtmutex.h>
	22	#include <linux/vmalloc.h>
	23	#include <linux/slab.h>
f2517eb7	24	#include <linux/list_lru.h>
0c972a05	25
f2517eb7	26	extern struct list_lru binder_alloc_lru;
0c972a05 TK	27	struct binder_transaction;
	28
	29	/**
	30	* struct binder_buffer - buffer used for binder transactions
	31	* @entry: entry alloc->buffers
	32	* @rb_node: node for allocated_buffers/free_buffers rb trees
	33	* @free: true if buffer is free
	34	* @allow_user_free: describe the second member of struct blah,
	35	* @async_transaction: describe the second member of struct blah,
	36	* @debug_id: describe the second member of struct blah,
	37	* @transaction: describe the second member of struct blah,
	38	* @target_node: describe the second member of struct blah,
	39	* @data_size: describe the second member of struct blah,
	40	* @offsets_size: describe the second member of struct blah,
	41	* @extra_buffers_size: describe the second member of struct blah,
	42	* @data:i describe the second member of struct blah,
	43	*
	44	* Bookkeeping structure for binder transaction buffers
	45	*/
	46	struct binder_buffer {
	47	struct list_head entry; /* free and allocated entries by address */
	48	struct rb_node rb_node; /* free entry by size or allocated entry */
	49	/* by address */
	50	unsigned free:1;
	51	unsigned allow_user_free:1;
	52	unsigned async_transaction:1;
53d311cf TK	53	unsigned free_in_progress:1;
53d311cf TK	54	unsigned debug_id:28;
0c972a05 TK	55
	56	struct binder_transaction *transaction;
	57
	58	struct binder_node *target_node;
	59	size_t data_size;
	60	size_t offsets_size;
	61	size_t extra_buffers_size;
74310e06	62	void *data;
0c972a05 TK	63	};
0c972a05 TK	64
f2517eb7 SY	65	/**
	66	* struct binder_lru_page - page object used for binder shrinker
	67	* @page_ptr: pointer to physical page in mmap'd space
	68	* @lru: entry in binder_alloc_lru
	69	* @alloc: binder_alloc for a proc
	70	*/
	71	struct binder_lru_page {
	72	struct list_head lru;
	73	struct page *page_ptr;
	74	struct binder_alloc *alloc;
	75	};
	76
0c972a05 TK	77	/**
	78	* struct binder_alloc - per-binder proc state for binder allocator
	79	* @vma: vm_area_struct passed to mmap_handler
	80	* (invarient after mmap)
	81	* @tsk: tid for task that called init for this proc
	82	* (invariant after init)
	83	* @vma_vm_mm: copy of vma->vm_mm (invarient after mmap)
	84	* @buffer: base of per-proc address space mapped via mmap
	85	* @user_buffer_offset: offset between user and kernel VAs for buffer
	86	* @buffers: list of all buffers for this proc
	87	* @free_buffers: rb tree of buffers available for allocation
	88	* sorted by size
	89	* @allocated_buffers: rb tree of allocated buffers sorted by address
	90	* @free_async_space: VA space available for async buffers. This is
	91	* initialized at mmap time to 1/2 the full VA space
f2517eb7	92	* @pages: array of binder_lru_page
0c972a05 TK	93	* @buffer_size: size of address space specified via mmap
0c972a05 TK	94	* @pid: pid for associated binder_proc (invariant after init)
8d9a3ab6	95	* @pages_high: high watermark of offset in @pages
0c972a05 TK	96	*
	97	* Bookkeeping structure for per-proc address space management for binder
	98	* buffers. It is normally initialized during binder_init() and binder_mmap()
	99	* calls. The address space is used for both user-visible buffers and for
	100	* struct binder_buffer objects used to track the user buffers
	101	*/
	102	struct binder_alloc {
	103	struct mutex mutex;
0c972a05 TK	104	struct vm_area_struct *vma;
	105	struct mm_struct *vma_vm_mm;
	106	void *buffer;
	107	ptrdiff_t user_buffer_offset;
	108	struct list_head buffers;
	109	struct rb_root free_buffers;
	110	struct rb_root allocated_buffers;
	111	size_t free_async_space;
f2517eb7	112	struct binder_lru_page *pages;
0c972a05 TK	113	size_t buffer_size;
	114	uint32_t buffer_free;
	115	int pid;
8d9a3ab6	116	size_t pages_high;
0c972a05 TK	117	};
0c972a05 TK	118
4175e2b4 SY	119	#ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST
	120	void binder_selftest_alloc(struct binder_alloc *alloc);
	121	#else
	122	static inline void binder_selftest_alloc(struct binder_alloc *alloc) {}
	123	#endif
f2517eb7 SY	124	enum lru_status binder_alloc_free_page(struct list_head *item,
	125	struct list_lru_one *lru,
	126	spinlock_t lock, void cb_arg);
0c972a05 TK	127	extern struct binder_buffer binder_alloc_new_buf(struct binder_alloc alloc,
	128	size_t data_size,
	129	size_t offsets_size,
	130	size_t extra_buffers_size,
	131	int is_async);
	132	extern void binder_alloc_init(struct binder_alloc *alloc);
f2517eb7	133	void binder_alloc_shrinker_init(void);
0c972a05 TK	134	extern void binder_alloc_vma_close(struct binder_alloc *alloc);
0c972a05 TK	135	extern struct binder_buffer *
53d311cf TK	136	binder_alloc_prepare_to_free(struct binder_alloc *alloc,
53d311cf TK	137	uintptr_t user_ptr);
0c972a05 TK	138	extern void binder_alloc_free_buf(struct binder_alloc *alloc,
	139	struct binder_buffer *buffer);
	140	extern int binder_alloc_mmap_handler(struct binder_alloc *alloc,
	141	struct vm_area_struct *vma);
	142	extern void binder_alloc_deferred_release(struct binder_alloc *alloc);
	143	extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc);
	144	extern void binder_alloc_print_allocated(struct seq_file *m,
	145	struct binder_alloc *alloc);
8ef4665a SY	146	void binder_alloc_print_pages(struct seq_file *m,
8ef4665a SY	147	struct binder_alloc *alloc);
0c972a05 TK	148
	149	/**
	150	* binder_alloc_get_free_async_space() - get free space available for async
	151	* @alloc: binder_alloc for this proc
	152	*
	153	* Return: the bytes remaining in the address-space for async transactions
	154	*/
	155	static inline size_t
	156	binder_alloc_get_free_async_space(struct binder_alloc *alloc)
	157	{
	158	size_t free_async_space;
	159
	160	mutex_lock(&alloc->mutex);
	161	free_async_space = alloc->free_async_space;
	162	mutex_unlock(&alloc->mutex);
	163	return free_async_space;
	164	}
	165
	166	/**
	167	* binder_alloc_get_user_buffer_offset() - get offset between kernel/user addrs
	168	* @alloc: binder_alloc for this proc
	169	*
	170	* Return: the offset between kernel and user-space addresses to use for
	171	* virtual address conversion
	172	*/
	173	static inline ptrdiff_t
	174	binder_alloc_get_user_buffer_offset(struct binder_alloc *alloc)
	175	{
	176	/*
	177	* user_buffer_offset is constant if vma is set and
	178	* undefined if vma is not set. It is possible to
	179	* get here with !alloc->vma if the target process
	180	* is dying while a transaction is being initiated.
	181	* Returning the old value is ok in this case and
	182	* the transaction will fail.
	183	*/
	184	return alloc->user_buffer_offset;
	185	}
	186
	187	#endif /* _LINUX_BINDER_ALLOC_H */
	188