/* * Copyright (C) 2017 Google, Inc. * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * */ #ifndef _LINUX_BINDER_ALLOC_H #define _LINUX_BINDER_ALLOC_H #include <linux/rbtree.h> #include <linux/list.h> #include <linux/mm.h> #include <linux/rtmutex.h> #include <linux/vmalloc.h> #include <linux/slab.h> #include <linux/list_lru.h> extern struct list_lru binder_alloc_lru; struct binder_transaction; /** * struct binder_buffer - buffer used for binder transactions * @entry: entry alloc->buffers * @rb_node: node for allocated_buffers/free_buffers rb trees * @free: true if buffer is free * @allow_user_free: describe the second member of struct blah, * @async_transaction: describe the second member of struct blah, * @debug_id: describe the second member of struct blah, * @transaction: describe the second member of struct blah, * @target_node: describe the second member of struct blah, * @data_size: describe the second member of struct blah, * @offsets_size: describe the second member of struct blah, * @extra_buffers_size: describe the second member of struct blah, * @data:i describe the second member of struct blah, * * Bookkeeping structure for binder transaction buffers */ struct binder_buffer { struct list_head entry; /* free and allocated entries by address */ struct rb_node rb_node; /* free entry by size or allocated entry */ /* by address */ unsigned free:1; unsigned allow_user_free:1; unsigned async_transaction:1; unsigned free_in_progress:1; unsigned debug_id:28; struct binder_transaction *transaction; struct binder_node *target_node; size_t data_size; size_t offsets_size; size_t extra_buffers_size; void *data; }; /** * struct binder_lru_page - page object used for binder shrinker * @page_ptr: pointer to physical page in mmap'd space * @lru: entry in binder_alloc_lru * @alloc: binder_alloc for a proc */ struct binder_lru_page { struct list_head lru; struct page *page_ptr; struct binder_alloc *alloc; }; /** * struct binder_alloc - per-binder proc state for binder allocator * @vma: vm_area_struct passed to mmap_handler * (invarient after mmap) * @tsk: tid for task that called init for this proc * (invariant after init) * @vma_vm_mm: copy of vma->vm_mm (invarient after mmap) * @buffer: base of per-proc address space mapped via mmap * @user_buffer_offset: offset between user and kernel VAs for buffer * @buffers: list of all buffers for this proc * @free_buffers: rb tree of buffers available for allocation * sorted by size * @allocated_buffers: rb tree of allocated buffers sorted by address * @free_async_space: VA space available for async buffers. This is * initialized at mmap time to 1/2 the full VA space * @pages: array of binder_lru_page * @buffer_size: size of address space specified via mmap * @pid: pid for associated binder_proc (invariant after init) * @pages_high: high watermark of offset in @pages * * Bookkeeping structure for per-proc address space management for binder * buffers. It is normally initialized during binder_init() and binder_mmap() * calls. The address space is used for both user-visible buffers and for * struct binder_buffer objects used to track the user buffers */ struct binder_alloc { struct mutex mutex; struct vm_area_struct *vma; struct mm_struct *vma_vm_mm; void *buffer; ptrdiff_t user_buffer_offset; struct list_head buffers; struct rb_root free_buffers; struct rb_root allocated_buffers; size_t free_async_space; struct binder_lru_page *pages; size_t buffer_size; uint32_t buffer_free; int pid; size_t pages_high; }; #ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST void binder_selftest_alloc(struct binder_alloc *alloc); #else static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} #endif enum lru_status binder_alloc_free_page(struct list_head *item, struct list_lru_one *lru, spinlock_t *lock, void *cb_arg); extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, size_t data_size, size_t offsets_size, size_t extra_buffers_size, int is_async); extern void binder_alloc_init(struct binder_alloc *alloc); extern int binder_alloc_shrinker_init(void); extern void binder_alloc_vma_close(struct binder_alloc *alloc); extern struct binder_buffer * binder_alloc_prepare_to_free(struct binder_alloc *alloc, uintptr_t user_ptr); extern void binder_alloc_free_buf(struct binder_alloc *alloc, struct binder_buffer *buffer); extern int binder_alloc_mmap_handler(struct binder_alloc *alloc, struct vm_area_struct *vma); extern void binder_alloc_deferred_release(struct binder_alloc *alloc); extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc); extern void binder_alloc_print_allocated(struct seq_file *m, struct binder_alloc *alloc); void binder_alloc_print_pages(struct seq_file *m, struct binder_alloc *alloc); /** * binder_alloc_get_free_async_space() - get free space available for async * @alloc: binder_alloc for this proc * * Return: the bytes remaining in the address-space for async transactions */ static inline size_t binder_alloc_get_free_async_space(struct binder_alloc *alloc) { size_t free_async_space; mutex_lock(&alloc->mutex); free_async_space = alloc->free_async_space; mutex_unlock(&alloc->mutex); return free_async_space; } /** * binder_alloc_get_user_buffer_offset() - get offset between kernel/user addrs * @alloc: binder_alloc for this proc * * Return: the offset between kernel and user-space addresses to use for * virtual address conversion */ static inline ptrdiff_t binder_alloc_get_user_buffer_offset(struct binder_alloc *alloc) { /* * user_buffer_offset is constant if vma is set and * undefined if vma is not set. It is possible to * get here with !alloc->vma if the target process * is dying while a transaction is being initiated. * Returning the old value is ok in this case and * the transaction will fail. */ return alloc->user_buffer_offset; } #endif /* _LINUX_BINDER_ALLOC_H */