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> 24 #include <linux/list_lru.h> 25 #include <uapi/linux/android/binder.h> 26 27 extern struct list_lru binder_alloc_lru; 28 struct binder_transaction; 29 30 /** 31 * struct binder_buffer - buffer used for binder transactions 32 * @entry: entry alloc->buffers 33 * @rb_node: node for allocated_buffers/free_buffers rb trees 34 * @free: %true if buffer is free 35 * @allow_user_free: %true if user is allowed to free buffer 36 * @async_transaction: %true if buffer is in use for an async txn 37 * @debug_id: unique ID for debugging 38 * @transaction: pointer to associated struct binder_transaction 39 * @target_node: struct binder_node associated with this buffer 40 * @data_size: size of @transaction data 41 * @offsets_size: size of array of offsets 42 * @extra_buffers_size: size of space for other objects (like sg lists) 43 * @user_data: user pointer to base of buffer space 44 * 45 * Bookkeeping structure for binder transaction buffers 46 */ 47 struct binder_buffer { 48 struct list_head entry; /* free and allocated entries by address */ 49 struct rb_node rb_node; /* free entry by size or allocated entry */ 50 /* by address */ 51 unsigned free:1; 52 unsigned allow_user_free:1; 53 unsigned async_transaction:1; 54 unsigned debug_id:29; 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; 62 void __user *user_data; 63 }; 64 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 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 * @buffers: list of all buffers for this proc 86 * @free_buffers: rb tree of buffers available for allocation 87 * sorted by size 88 * @allocated_buffers: rb tree of allocated buffers sorted by address 89 * @free_async_space: VA space available for async buffers. This is 90 * initialized at mmap time to 1/2 the full VA space 91 * @pages: array of binder_lru_page 92 * @buffer_size: size of address space specified via mmap 93 * @pid: pid for associated binder_proc (invariant after init) 94 * @pages_high: high watermark of offset in @pages 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 */ 101 struct 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 }; 116 117 #ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST 118 void binder_selftest_alloc(struct binder_alloc *alloc); 119 #else 120 static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} 121 #endif 122 enum lru_status binder_alloc_free_page(struct list_head *item, 123 struct list_lru_one *lru, 124 spinlock_t *lock, void *cb_arg); 125 extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, 126 size_t data_size, 127 size_t offsets_size, 128 size_t extra_buffers_size, 129 int is_async); 130 extern void binder_alloc_init(struct binder_alloc *alloc); 131 extern int binder_alloc_shrinker_init(void); 132 extern void binder_alloc_vma_close(struct binder_alloc *alloc); 133 extern struct binder_buffer * 134 binder_alloc_prepare_to_free(struct binder_alloc *alloc, 135 uintptr_t user_ptr); 136 extern void binder_alloc_free_buf(struct binder_alloc *alloc, 137 struct binder_buffer *buffer); 138 extern int binder_alloc_mmap_handler(struct binder_alloc *alloc, 139 struct vm_area_struct *vma); 140 extern void binder_alloc_deferred_release(struct binder_alloc *alloc); 141 extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc); 142 extern void binder_alloc_print_allocated(struct seq_file *m, 143 struct binder_alloc *alloc); 144 void binder_alloc_print_pages(struct seq_file *m, 145 struct binder_alloc *alloc); 146 147 /** 148 * binder_alloc_get_free_async_space() - get free space available for async 149 * @alloc: binder_alloc for this proc 150 * 151 * Return: the bytes remaining in the address-space for async transactions 152 */ 153 static inline size_t 154 binder_alloc_get_free_async_space(struct binder_alloc *alloc) 155 { 156 size_t free_async_space; 157 158 mutex_lock(&alloc->mutex); 159 free_async_space = alloc->free_async_space; 160 mutex_unlock(&alloc->mutex); 161 return free_async_space; 162 } 163 164 unsigned long 165 binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, 166 struct binder_buffer *buffer, 167 binder_size_t buffer_offset, 168 const void __user *from, 169 size_t bytes); 170 171 void binder_alloc_copy_to_buffer(struct binder_alloc *alloc, 172 struct binder_buffer *buffer, 173 binder_size_t buffer_offset, 174 void *src, 175 size_t bytes); 176 177 void binder_alloc_copy_from_buffer(struct binder_alloc *alloc, 178 void *dest, 179 struct binder_buffer *buffer, 180 binder_size_t buffer_offset, 181 size_t bytes); 182 183 #endif /* _LINUX_BINDER_ALLOC_H */ 184 185