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 18 extern struct list_lru binder_alloc_lru; 19 struct 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 * @debug_id: unique ID for debugging 30 * @transaction: pointer to associated struct binder_transaction 31 * @target_node: struct binder_node associated with this buffer 32 * @data_size: size of @transaction data 33 * @offsets_size: size of array of offsets 34 * @extra_buffers_size: size of space for other objects (like sg lists) 35 * @user_data: user pointer to base of buffer space 36 * @pid: pid to attribute the buffer to (caller) 37 * 38 * Bookkeeping structure for binder transaction buffers 39 */ 40 struct binder_buffer { 41 struct list_head entry; /* free and allocated entries by address */ 42 struct rb_node rb_node; /* free entry by size or allocated entry */ 43 /* by address */ 44 unsigned free:1; 45 unsigned clear_on_free:1; 46 unsigned allow_user_free:1; 47 unsigned async_transaction:1; 48 unsigned debug_id:28; 49 50 struct binder_transaction *transaction; 51 52 struct binder_node *target_node; 53 size_t data_size; 54 size_t offsets_size; 55 size_t extra_buffers_size; 56 void __user *user_data; 57 int pid; 58 }; 59 60 /** 61 * struct binder_lru_page - page object used for binder shrinker 62 * @page_ptr: pointer to physical page in mmap'd space 63 * @lru: entry in binder_alloc_lru 64 * @alloc: binder_alloc for a proc 65 */ 66 struct binder_lru_page { 67 struct list_head lru; 68 struct page *page_ptr; 69 struct binder_alloc *alloc; 70 }; 71 72 /** 73 * struct binder_alloc - per-binder proc state for binder allocator 74 * @vma: vm_area_struct passed to mmap_handler 75 * (invarient after mmap) 76 * @tsk: tid for task that called init for this proc 77 * (invariant after init) 78 * @vma_vm_mm: copy of vma->vm_mm (invarient after mmap) 79 * @buffer: base of per-proc address space mapped via mmap 80 * @buffers: list of all buffers for this proc 81 * @free_buffers: rb tree of buffers available for allocation 82 * sorted by size 83 * @allocated_buffers: rb tree of allocated buffers sorted by address 84 * @free_async_space: VA space available for async buffers. This is 85 * initialized at mmap time to 1/2 the full VA space 86 * @pages: array of binder_lru_page 87 * @buffer_size: size of address space specified via mmap 88 * @pid: pid for associated binder_proc (invariant after init) 89 * @pages_high: high watermark of offset in @pages 90 * 91 * Bookkeeping structure for per-proc address space management for binder 92 * buffers. It is normally initialized during binder_init() and binder_mmap() 93 * calls. The address space is used for both user-visible buffers and for 94 * struct binder_buffer objects used to track the user buffers 95 */ 96 struct binder_alloc { 97 struct mutex mutex; 98 struct vm_area_struct *vma; 99 struct mm_struct *vma_vm_mm; 100 void __user *buffer; 101 struct list_head buffers; 102 struct rb_root free_buffers; 103 struct rb_root allocated_buffers; 104 size_t free_async_space; 105 struct binder_lru_page *pages; 106 size_t buffer_size; 107 uint32_t buffer_free; 108 int pid; 109 size_t pages_high; 110 }; 111 112 #ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST 113 void binder_selftest_alloc(struct binder_alloc *alloc); 114 #else 115 static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} 116 #endif 117 enum lru_status binder_alloc_free_page(struct list_head *item, 118 struct list_lru_one *lru, 119 spinlock_t *lock, void *cb_arg); 120 extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, 121 size_t data_size, 122 size_t offsets_size, 123 size_t extra_buffers_size, 124 int is_async, 125 int pid); 126 extern void binder_alloc_init(struct binder_alloc *alloc); 127 extern int binder_alloc_shrinker_init(void); 128 extern void binder_alloc_vma_close(struct binder_alloc *alloc); 129 extern struct binder_buffer * 130 binder_alloc_prepare_to_free(struct binder_alloc *alloc, 131 uintptr_t user_ptr); 132 extern void binder_alloc_free_buf(struct binder_alloc *alloc, 133 struct binder_buffer *buffer); 134 extern int binder_alloc_mmap_handler(struct binder_alloc *alloc, 135 struct vm_area_struct *vma); 136 extern void binder_alloc_deferred_release(struct binder_alloc *alloc); 137 extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc); 138 extern void binder_alloc_print_allocated(struct seq_file *m, 139 struct binder_alloc *alloc); 140 void binder_alloc_print_pages(struct seq_file *m, 141 struct binder_alloc *alloc); 142 143 /** 144 * binder_alloc_get_free_async_space() - get free space available for async 145 * @alloc: binder_alloc for this proc 146 * 147 * Return: the bytes remaining in the address-space for async transactions 148 */ 149 static inline size_t 150 binder_alloc_get_free_async_space(struct binder_alloc *alloc) 151 { 152 size_t free_async_space; 153 154 mutex_lock(&alloc->mutex); 155 free_async_space = alloc->free_async_space; 156 mutex_unlock(&alloc->mutex); 157 return free_async_space; 158 } 159 160 unsigned long 161 binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, 162 struct binder_buffer *buffer, 163 binder_size_t buffer_offset, 164 const void __user *from, 165 size_t bytes); 166 167 int binder_alloc_copy_to_buffer(struct binder_alloc *alloc, 168 struct binder_buffer *buffer, 169 binder_size_t buffer_offset, 170 void *src, 171 size_t bytes); 172 173 int binder_alloc_copy_from_buffer(struct binder_alloc *alloc, 174 void *dest, 175 struct binder_buffer *buffer, 176 binder_size_t buffer_offset, 177 size_t bytes); 178 179 #endif /* _LINUX_BINDER_ALLOC_H */ 180 181