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/spinlock.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_freelist; 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 struct binder_transaction *transaction; 53 struct binder_node *target_node; 54 size_t data_size; 55 size_t offsets_size; 56 size_t extra_buffers_size; 57 unsigned long user_data; 58 int pid; 59 }; 60 61 /** 62 * struct binder_lru_page - page object used for binder shrinker 63 * @page_ptr: pointer to physical page in mmap'd space 64 * @lru: entry in binder_freelist 65 * @alloc: binder_alloc for a proc 66 */ 67 struct binder_lru_page { 68 struct list_head lru; 69 struct page *page_ptr; 70 struct binder_alloc *alloc; 71 }; 72 73 /** 74 * struct binder_alloc - per-binder proc state for binder allocator 75 * @lock: protects binder_alloc fields 76 * @vma: vm_area_struct passed to mmap_handler 77 * (invariant after mmap) 78 * @mm: copy of task->mm (invariant after open) 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 * @oneway_spam_detected: %true if oneway spam detection fired, clear that 91 * flag once the async buffer has returned to a healthy state 92 * 93 * Bookkeeping structure for per-proc address space management for binder 94 * buffers. It is normally initialized during binder_init() and binder_mmap() 95 * calls. The address space is used for both user-visible buffers and for 96 * struct binder_buffer objects used to track the user buffers 97 */ 98 struct binder_alloc { 99 spinlock_t lock; 100 struct vm_area_struct *vma; 101 struct mm_struct *mm; 102 unsigned long buffer; 103 struct list_head buffers; 104 struct rb_root free_buffers; 105 struct rb_root allocated_buffers; 106 size_t free_async_space; 107 struct binder_lru_page *pages; 108 size_t buffer_size; 109 int pid; 110 size_t pages_high; 111 bool oneway_spam_detected; 112 }; 113 114 #ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST 115 void binder_selftest_alloc(struct binder_alloc *alloc); 116 #else 117 static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} 118 #endif 119 enum lru_status binder_alloc_free_page(struct list_head *item, 120 struct list_lru_one *lru, 121 spinlock_t *lock, void *cb_arg); 122 struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, 123 size_t data_size, 124 size_t offsets_size, 125 size_t extra_buffers_size, 126 int is_async); 127 void binder_alloc_init(struct binder_alloc *alloc); 128 int binder_alloc_shrinker_init(void); 129 void binder_alloc_shrinker_exit(void); 130 void binder_alloc_vma_close(struct binder_alloc *alloc); 131 struct binder_buffer * 132 binder_alloc_prepare_to_free(struct binder_alloc *alloc, 133 unsigned long user_ptr); 134 void binder_alloc_free_buf(struct binder_alloc *alloc, 135 struct binder_buffer *buffer); 136 int binder_alloc_mmap_handler(struct binder_alloc *alloc, 137 struct vm_area_struct *vma); 138 void binder_alloc_deferred_release(struct binder_alloc *alloc); 139 int binder_alloc_get_allocated_count(struct binder_alloc *alloc); 140 void binder_alloc_print_allocated(struct seq_file *m, 141 struct binder_alloc *alloc); 142 void binder_alloc_print_pages(struct seq_file *m, 143 struct binder_alloc *alloc); 144 145 /** 146 * binder_alloc_get_free_async_space() - get free space available for async 147 * @alloc: binder_alloc for this proc 148 * 149 * Return: the bytes remaining in the address-space for async transactions 150 */ 151 static inline size_t 152 binder_alloc_get_free_async_space(struct binder_alloc *alloc) 153 { 154 size_t free_async_space; 155 156 spin_lock(&alloc->lock); 157 free_async_space = alloc->free_async_space; 158 spin_unlock(&alloc->lock); 159 return free_async_space; 160 } 161 162 unsigned long 163 binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, 164 struct binder_buffer *buffer, 165 binder_size_t buffer_offset, 166 const void __user *from, 167 size_t bytes); 168 169 int binder_alloc_copy_to_buffer(struct binder_alloc *alloc, 170 struct binder_buffer *buffer, 171 binder_size_t buffer_offset, 172 void *src, 173 size_t bytes); 174 175 int binder_alloc_copy_from_buffer(struct binder_alloc *alloc, 176 void *dest, 177 struct binder_buffer *buffer, 178 binder_size_t buffer_offset, 179 size_t bytes); 180 181 #endif /* _LINUX_BINDER_ALLOC_H */ 182 183