binder_alloc.h (6593B)
1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * Copyright (C) 2017 Google, Inc. 4 */ 5 6#ifndef _LINUX_BINDER_ALLOC_H 7#define _LINUX_BINDER_ALLOC_H 8 9#include <linux/rbtree.h> 10#include <linux/list.h> 11#include <linux/mm.h> 12#include <linux/rtmutex.h> 13#include <linux/vmalloc.h> 14#include <linux/slab.h> 15#include <linux/list_lru.h> 16#include <uapi/linux/android/binder.h> 17 18extern struct list_lru binder_alloc_lru; 19struct binder_transaction; 20 21/** 22 * struct binder_buffer - buffer used for binder transactions 23 * @entry: entry alloc->buffers 24 * @rb_node: node for allocated_buffers/free_buffers rb trees 25 * @free: %true if buffer is free 26 * @clear_on_free: %true if buffer must be zeroed after use 27 * @allow_user_free: %true if user is allowed to free buffer 28 * @async_transaction: %true if buffer is in use for an async txn 29 * @oneway_spam_suspect: %true if total async allocate size just exceed 30 * spamming detect threshold 31 * @debug_id: unique ID for debugging 32 * @transaction: pointer to associated struct binder_transaction 33 * @target_node: struct binder_node associated with this buffer 34 * @data_size: size of @transaction data 35 * @offsets_size: size of array of offsets 36 * @extra_buffers_size: size of space for other objects (like sg lists) 37 * @user_data: user pointer to base of buffer space 38 * @pid: pid to attribute the buffer to (caller) 39 * 40 * Bookkeeping structure for binder transaction buffers 41 */ 42struct binder_buffer { 43 struct list_head entry; /* free and allocated entries by address */ 44 struct rb_node rb_node; /* free entry by size or allocated entry */ 45 /* by address */ 46 unsigned free:1; 47 unsigned clear_on_free:1; 48 unsigned allow_user_free:1; 49 unsigned async_transaction:1; 50 unsigned oneway_spam_suspect:1; 51 unsigned debug_id:27; 52 53 struct binder_transaction *transaction; 54 55 struct binder_node *target_node; 56 size_t data_size; 57 size_t offsets_size; 58 size_t extra_buffers_size; 59 void __user *user_data; 60 int pid; 61}; 62 63/** 64 * struct binder_lru_page - page object used for binder shrinker 65 * @page_ptr: pointer to physical page in mmap'd space 66 * @lru: entry in binder_alloc_lru 67 * @alloc: binder_alloc for a proc 68 */ 69struct binder_lru_page { 70 struct list_head lru; 71 struct page *page_ptr; 72 struct binder_alloc *alloc; 73}; 74 75/** 76 * struct binder_alloc - per-binder proc state for binder allocator 77 * @vma: vm_area_struct passed to mmap_handler 78 * (invarient after mmap) 79 * @tsk: tid for task that called init for this proc 80 * (invariant after init) 81 * @vma_vm_mm: copy of vma->vm_mm (invarient after mmap) 82 * @buffer: base of per-proc address space mapped via mmap 83 * @buffers: list of all buffers for this proc 84 * @free_buffers: rb tree of buffers available for allocation 85 * sorted by size 86 * @allocated_buffers: rb tree of allocated buffers sorted by address 87 * @free_async_space: VA space available for async buffers. This is 88 * initialized at mmap time to 1/2 the full VA space 89 * @pages: array of binder_lru_page 90 * @buffer_size: size of address space specified via mmap 91 * @pid: pid for associated binder_proc (invariant after init) 92 * @pages_high: high watermark of offset in @pages 93 * @oneway_spam_detected: %true if oneway spam detection fired, clear that 94 * flag once the async buffer has returned to a healthy state 95 * 96 * Bookkeeping structure for per-proc address space management for binder 97 * buffers. It is normally initialized during binder_init() and binder_mmap() 98 * calls. The address space is used for both user-visible buffers and for 99 * struct binder_buffer objects used to track the user buffers 100 */ 101struct binder_alloc { 102 struct mutex mutex; 103 struct vm_area_struct *vma; 104 struct mm_struct *vma_vm_mm; 105 void __user *buffer; 106 struct list_head buffers; 107 struct rb_root free_buffers; 108 struct rb_root allocated_buffers; 109 size_t free_async_space; 110 struct binder_lru_page *pages; 111 size_t buffer_size; 112 uint32_t buffer_free; 113 int pid; 114 size_t pages_high; 115 bool oneway_spam_detected; 116}; 117 118#ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST 119void binder_selftest_alloc(struct binder_alloc *alloc); 120#else 121static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} 122#endif 123enum lru_status binder_alloc_free_page(struct list_head *item, 124 struct list_lru_one *lru, 125 spinlock_t *lock, void *cb_arg); 126extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, 127 size_t data_size, 128 size_t offsets_size, 129 size_t extra_buffers_size, 130 int is_async, 131 int pid); 132extern void binder_alloc_init(struct binder_alloc *alloc); 133extern int binder_alloc_shrinker_init(void); 134extern void binder_alloc_vma_close(struct binder_alloc *alloc); 135extern struct binder_buffer * 136binder_alloc_prepare_to_free(struct binder_alloc *alloc, 137 uintptr_t user_ptr); 138extern void binder_alloc_free_buf(struct binder_alloc *alloc, 139 struct binder_buffer *buffer); 140extern int binder_alloc_mmap_handler(struct binder_alloc *alloc, 141 struct vm_area_struct *vma); 142extern void binder_alloc_deferred_release(struct binder_alloc *alloc); 143extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc); 144extern void binder_alloc_print_allocated(struct seq_file *m, 145 struct binder_alloc *alloc); 146void binder_alloc_print_pages(struct seq_file *m, 147 struct binder_alloc *alloc); 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 */ 155static inline size_t 156binder_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 166unsigned long 167binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, 168 struct binder_buffer *buffer, 169 binder_size_t buffer_offset, 170 const void __user *from, 171 size_t bytes); 172 173int binder_alloc_copy_to_buffer(struct binder_alloc *alloc, 174 struct binder_buffer *buffer, 175 binder_size_t buffer_offset, 176 void *src, 177 size_t bytes); 178 179int binder_alloc_copy_from_buffer(struct binder_alloc *alloc, 180 void *dest, 181 struct binder_buffer *buffer, 182 binder_size_t buffer_offset, 183 size_t bytes); 184 185#endif /* _LINUX_BINDER_ALLOC_H */ 186