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 * @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 */ 42 struct 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 */ 69 struct 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 * @mutex: protects binder_alloc fields 78 * @vma_addr: vm_area_struct->vm_start passed to mmap_handler 79 * (invariant after mmap) 80 * @mm: copy of task->mm (invariant after open) 81 * @buffer: base of per-proc address space mapped via mmap 82 * @buffers: list of all buffers for this proc 83 * @free_buffers: rb tree of buffers available for allocation 84 * sorted by size 85 * @allocated_buffers: rb tree of allocated buffers sorted by address 86 * @free_async_space: VA space available for async buffers. This is 87 * initialized at mmap time to 1/2 the full VA space 88 * @pages: array of binder_lru_page 89 * @buffer_size: size of address space specified via mmap 90 * @pid: pid for associated binder_proc (invariant after init) 91 * @pages_high: high watermark of offset in @pages 92 * @oneway_spam_detected: %true if oneway spam detection fired, clear that 93 * flag once the async buffer has returned to a healthy state 94 * 95 * Bookkeeping structure for per-proc address space management for binder 96 * buffers. It is normally initialized during binder_init() and binder_mmap() 97 * calls. The address space is used for both user-visible buffers and for 98 * struct binder_buffer objects used to track the user buffers 99 */ 100 struct binder_alloc { 101 struct mutex mutex; 102 unsigned long vma_addr; 103 struct mm_struct *mm; 104 void __user *buffer; 105 struct list_head buffers; 106 struct rb_root free_buffers; 107 struct rb_root allocated_buffers; 108 size_t free_async_space; 109 struct binder_lru_page *pages; 110 size_t buffer_size; 111 int pid; 112 size_t pages_high; 113 bool oneway_spam_detected; 114 }; 115 116 #ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST 117 void binder_selftest_alloc(struct binder_alloc *alloc); 118 #else 119 static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} 120 #endif 121 enum lru_status binder_alloc_free_page(struct list_head *item, 122 struct list_lru_one *lru, 123 spinlock_t *lock, void *cb_arg); 124 extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, 125 size_t data_size, 126 size_t offsets_size, 127 size_t extra_buffers_size, 128 int is_async, 129 int pid); 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 int 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 int 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