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 * @allow_user_free: %true if user is allowed to free buffer 27 * @async_transaction: %true if buffer is in use for an async txn 28 * @debug_id: unique ID for debugging 29 * @transaction: pointer to associated struct binder_transaction 30 * @target_node: struct binder_node associated with this buffer 31 * @data_size: size of @transaction data 32 * @offsets_size: size of array of offsets 33 * @extra_buffers_size: size of space for other objects (like sg lists) 34 * @user_data: user pointer to base of buffer space 35 * 36 * Bookkeeping structure for binder transaction buffers 37 */ 38 struct binder_buffer { 39 struct list_head entry; /* free and allocated entries by address */ 40 struct rb_node rb_node; /* free entry by size or allocated entry */ 41 /* by address */ 42 unsigned free:1; 43 unsigned allow_user_free:1; 44 unsigned async_transaction:1; 45 unsigned debug_id:29; 46 47 struct binder_transaction *transaction; 48 49 struct binder_node *target_node; 50 size_t data_size; 51 size_t offsets_size; 52 size_t extra_buffers_size; 53 void __user *user_data; 54 }; 55 56 /** 57 * struct binder_lru_page - page object used for binder shrinker 58 * @page_ptr: pointer to physical page in mmap'd space 59 * @lru: entry in binder_alloc_lru 60 * @alloc: binder_alloc for a proc 61 */ 62 struct binder_lru_page { 63 struct list_head lru; 64 struct page *page_ptr; 65 struct binder_alloc *alloc; 66 }; 67 68 /** 69 * struct binder_alloc - per-binder proc state for binder allocator 70 * @vma: vm_area_struct passed to mmap_handler 71 * (invarient after mmap) 72 * @tsk: tid for task that called init for this proc 73 * (invariant after init) 74 * @vma_vm_mm: copy of vma->vm_mm (invarient after mmap) 75 * @buffer: base of per-proc address space mapped via mmap 76 * @buffers: list of all buffers for this proc 77 * @free_buffers: rb tree of buffers available for allocation 78 * sorted by size 79 * @allocated_buffers: rb tree of allocated buffers sorted by address 80 * @free_async_space: VA space available for async buffers. This is 81 * initialized at mmap time to 1/2 the full VA space 82 * @pages: array of binder_lru_page 83 * @buffer_size: size of address space specified via mmap 84 * @pid: pid for associated binder_proc (invariant after init) 85 * @pages_high: high watermark of offset in @pages 86 * 87 * Bookkeeping structure for per-proc address space management for binder 88 * buffers. It is normally initialized during binder_init() and binder_mmap() 89 * calls. The address space is used for both user-visible buffers and for 90 * struct binder_buffer objects used to track the user buffers 91 */ 92 struct binder_alloc { 93 struct mutex mutex; 94 struct vm_area_struct *vma; 95 struct mm_struct *vma_vm_mm; 96 void __user *buffer; 97 struct list_head buffers; 98 struct rb_root free_buffers; 99 struct rb_root allocated_buffers; 100 size_t free_async_space; 101 struct binder_lru_page *pages; 102 size_t buffer_size; 103 uint32_t buffer_free; 104 int pid; 105 size_t pages_high; 106 }; 107 108 #ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST 109 void binder_selftest_alloc(struct binder_alloc *alloc); 110 #else 111 static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} 112 #endif 113 enum lru_status binder_alloc_free_page(struct list_head *item, 114 struct list_lru_one *lru, 115 spinlock_t *lock, void *cb_arg); 116 extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, 117 size_t data_size, 118 size_t offsets_size, 119 size_t extra_buffers_size, 120 int is_async); 121 extern void binder_alloc_init(struct binder_alloc *alloc); 122 extern int binder_alloc_shrinker_init(void); 123 extern void binder_alloc_vma_close(struct binder_alloc *alloc); 124 extern struct binder_buffer * 125 binder_alloc_prepare_to_free(struct binder_alloc *alloc, 126 uintptr_t user_ptr); 127 extern void binder_alloc_free_buf(struct binder_alloc *alloc, 128 struct binder_buffer *buffer); 129 extern int binder_alloc_mmap_handler(struct binder_alloc *alloc, 130 struct vm_area_struct *vma); 131 extern void binder_alloc_deferred_release(struct binder_alloc *alloc); 132 extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc); 133 extern void binder_alloc_print_allocated(struct seq_file *m, 134 struct binder_alloc *alloc); 135 void binder_alloc_print_pages(struct seq_file *m, 136 struct binder_alloc *alloc); 137 138 /** 139 * binder_alloc_get_free_async_space() - get free space available for async 140 * @alloc: binder_alloc for this proc 141 * 142 * Return: the bytes remaining in the address-space for async transactions 143 */ 144 static inline size_t 145 binder_alloc_get_free_async_space(struct binder_alloc *alloc) 146 { 147 size_t free_async_space; 148 149 mutex_lock(&alloc->mutex); 150 free_async_space = alloc->free_async_space; 151 mutex_unlock(&alloc->mutex); 152 return free_async_space; 153 } 154 155 unsigned long 156 binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, 157 struct binder_buffer *buffer, 158 binder_size_t buffer_offset, 159 const void __user *from, 160 size_t bytes); 161 162 int binder_alloc_copy_to_buffer(struct binder_alloc *alloc, 163 struct binder_buffer *buffer, 164 binder_size_t buffer_offset, 165 void *src, 166 size_t bytes); 167 168 int binder_alloc_copy_from_buffer(struct binder_alloc *alloc, 169 void *dest, 170 struct binder_buffer *buffer, 171 binder_size_t buffer_offset, 172 size_t bytes); 173 174 #endif /* _LINUX_BINDER_ALLOC_H */ 175 176