binder_internal.h (20786B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2 3#ifndef _LINUX_BINDER_INTERNAL_H 4#define _LINUX_BINDER_INTERNAL_H 5 6#include <linux/export.h> 7#include <linux/fs.h> 8#include <linux/list.h> 9#include <linux/miscdevice.h> 10#include <linux/mutex.h> 11#include <linux/refcount.h> 12#include <linux/stddef.h> 13#include <linux/types.h> 14#include <linux/uidgid.h> 15#include <uapi/linux/android/binderfs.h> 16#include "binder_alloc.h" 17 18struct binder_context { 19 struct binder_node *binder_context_mgr_node; 20 struct mutex context_mgr_node_lock; 21 kuid_t binder_context_mgr_uid; 22 const char *name; 23}; 24 25/** 26 * struct binder_device - information about a binder device node 27 * @hlist: list of binder devices (only used for devices requested via 28 * CONFIG_ANDROID_BINDER_DEVICES) 29 * @miscdev: information about a binder character device node 30 * @context: binder context information 31 * @binderfs_inode: This is the inode of the root dentry of the super block 32 * belonging to a binderfs mount. 33 */ 34struct binder_device { 35 struct hlist_node hlist; 36 struct miscdevice miscdev; 37 struct binder_context context; 38 struct inode *binderfs_inode; 39 refcount_t ref; 40}; 41 42/** 43 * binderfs_mount_opts - mount options for binderfs 44 * @max: maximum number of allocatable binderfs binder devices 45 * @stats_mode: enable binder stats in binderfs. 46 */ 47struct binderfs_mount_opts { 48 int max; 49 int stats_mode; 50}; 51 52/** 53 * binderfs_info - information about a binderfs mount 54 * @ipc_ns: The ipc namespace the binderfs mount belongs to. 55 * @control_dentry: This records the dentry of this binderfs mount 56 * binder-control device. 57 * @root_uid: uid that needs to be used when a new binder device is 58 * created. 59 * @root_gid: gid that needs to be used when a new binder device is 60 * created. 61 * @mount_opts: The mount options in use. 62 * @device_count: The current number of allocated binder devices. 63 * @proc_log_dir: Pointer to the directory dentry containing process-specific 64 * logs. 65 */ 66struct binderfs_info { 67 struct ipc_namespace *ipc_ns; 68 struct dentry *control_dentry; 69 kuid_t root_uid; 70 kgid_t root_gid; 71 struct binderfs_mount_opts mount_opts; 72 int device_count; 73 struct dentry *proc_log_dir; 74}; 75 76extern const struct file_operations binder_fops; 77 78extern char *binder_devices_param; 79 80#ifdef CONFIG_ANDROID_BINDERFS 81extern bool is_binderfs_device(const struct inode *inode); 82extern struct dentry *binderfs_create_file(struct dentry *dir, const char *name, 83 const struct file_operations *fops, 84 void *data); 85extern void binderfs_remove_file(struct dentry *dentry); 86#else 87static inline bool is_binderfs_device(const struct inode *inode) 88{ 89 return false; 90} 91static inline struct dentry *binderfs_create_file(struct dentry *dir, 92 const char *name, 93 const struct file_operations *fops, 94 void *data) 95{ 96 return NULL; 97} 98static inline void binderfs_remove_file(struct dentry *dentry) {} 99#endif 100 101#ifdef CONFIG_ANDROID_BINDERFS 102extern int __init init_binderfs(void); 103#else 104static inline int __init init_binderfs(void) 105{ 106 return 0; 107} 108#endif 109 110int binder_stats_show(struct seq_file *m, void *unused); 111DEFINE_SHOW_ATTRIBUTE(binder_stats); 112 113int binder_state_show(struct seq_file *m, void *unused); 114DEFINE_SHOW_ATTRIBUTE(binder_state); 115 116int binder_transactions_show(struct seq_file *m, void *unused); 117DEFINE_SHOW_ATTRIBUTE(binder_transactions); 118 119int binder_transaction_log_show(struct seq_file *m, void *unused); 120DEFINE_SHOW_ATTRIBUTE(binder_transaction_log); 121 122struct binder_transaction_log_entry { 123 int debug_id; 124 int debug_id_done; 125 int call_type; 126 int from_proc; 127 int from_thread; 128 int target_handle; 129 int to_proc; 130 int to_thread; 131 int to_node; 132 int data_size; 133 int offsets_size; 134 int return_error_line; 135 uint32_t return_error; 136 uint32_t return_error_param; 137 char context_name[BINDERFS_MAX_NAME + 1]; 138}; 139 140struct binder_transaction_log { 141 atomic_t cur; 142 bool full; 143 struct binder_transaction_log_entry entry[32]; 144}; 145 146enum binder_stat_types { 147 BINDER_STAT_PROC, 148 BINDER_STAT_THREAD, 149 BINDER_STAT_NODE, 150 BINDER_STAT_REF, 151 BINDER_STAT_DEATH, 152 BINDER_STAT_TRANSACTION, 153 BINDER_STAT_TRANSACTION_COMPLETE, 154 BINDER_STAT_COUNT 155}; 156 157struct binder_stats { 158 atomic_t br[_IOC_NR(BR_ONEWAY_SPAM_SUSPECT) + 1]; 159 atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1]; 160 atomic_t obj_created[BINDER_STAT_COUNT]; 161 atomic_t obj_deleted[BINDER_STAT_COUNT]; 162}; 163 164/** 165 * struct binder_work - work enqueued on a worklist 166 * @entry: node enqueued on list 167 * @type: type of work to be performed 168 * 169 * There are separate work lists for proc, thread, and node (async). 170 */ 171struct binder_work { 172 struct list_head entry; 173 174 enum binder_work_type { 175 BINDER_WORK_TRANSACTION = 1, 176 BINDER_WORK_TRANSACTION_COMPLETE, 177 BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT, 178 BINDER_WORK_RETURN_ERROR, 179 BINDER_WORK_NODE, 180 BINDER_WORK_DEAD_BINDER, 181 BINDER_WORK_DEAD_BINDER_AND_CLEAR, 182 BINDER_WORK_CLEAR_DEATH_NOTIFICATION, 183 } type; 184}; 185 186struct binder_error { 187 struct binder_work work; 188 uint32_t cmd; 189}; 190 191/** 192 * struct binder_node - binder node bookkeeping 193 * @debug_id: unique ID for debugging 194 * (invariant after initialized) 195 * @lock: lock for node fields 196 * @work: worklist element for node work 197 * (protected by @proc->inner_lock) 198 * @rb_node: element for proc->nodes tree 199 * (protected by @proc->inner_lock) 200 * @dead_node: element for binder_dead_nodes list 201 * (protected by binder_dead_nodes_lock) 202 * @proc: binder_proc that owns this node 203 * (invariant after initialized) 204 * @refs: list of references on this node 205 * (protected by @lock) 206 * @internal_strong_refs: used to take strong references when 207 * initiating a transaction 208 * (protected by @proc->inner_lock if @proc 209 * and by @lock) 210 * @local_weak_refs: weak user refs from local process 211 * (protected by @proc->inner_lock if @proc 212 * and by @lock) 213 * @local_strong_refs: strong user refs from local process 214 * (protected by @proc->inner_lock if @proc 215 * and by @lock) 216 * @tmp_refs: temporary kernel refs 217 * (protected by @proc->inner_lock while @proc 218 * is valid, and by binder_dead_nodes_lock 219 * if @proc is NULL. During inc/dec and node release 220 * it is also protected by @lock to provide safety 221 * as the node dies and @proc becomes NULL) 222 * @ptr: userspace pointer for node 223 * (invariant, no lock needed) 224 * @cookie: userspace cookie for node 225 * (invariant, no lock needed) 226 * @has_strong_ref: userspace notified of strong ref 227 * (protected by @proc->inner_lock if @proc 228 * and by @lock) 229 * @pending_strong_ref: userspace has acked notification of strong ref 230 * (protected by @proc->inner_lock if @proc 231 * and by @lock) 232 * @has_weak_ref: userspace notified of weak ref 233 * (protected by @proc->inner_lock if @proc 234 * and by @lock) 235 * @pending_weak_ref: userspace has acked notification of weak ref 236 * (protected by @proc->inner_lock if @proc 237 * and by @lock) 238 * @has_async_transaction: async transaction to node in progress 239 * (protected by @lock) 240 * @accept_fds: file descriptor operations supported for node 241 * (invariant after initialized) 242 * @min_priority: minimum scheduling priority 243 * (invariant after initialized) 244 * @txn_security_ctx: require sender's security context 245 * (invariant after initialized) 246 * @async_todo: list of async work items 247 * (protected by @proc->inner_lock) 248 * 249 * Bookkeeping structure for binder nodes. 250 */ 251struct binder_node { 252 int debug_id; 253 spinlock_t lock; 254 struct binder_work work; 255 union { 256 struct rb_node rb_node; 257 struct hlist_node dead_node; 258 }; 259 struct binder_proc *proc; 260 struct hlist_head refs; 261 int internal_strong_refs; 262 int local_weak_refs; 263 int local_strong_refs; 264 int tmp_refs; 265 binder_uintptr_t ptr; 266 binder_uintptr_t cookie; 267 struct { 268 /* 269 * bitfield elements protected by 270 * proc inner_lock 271 */ 272 u8 has_strong_ref:1; 273 u8 pending_strong_ref:1; 274 u8 has_weak_ref:1; 275 u8 pending_weak_ref:1; 276 }; 277 struct { 278 /* 279 * invariant after initialization 280 */ 281 u8 accept_fds:1; 282 u8 txn_security_ctx:1; 283 u8 min_priority; 284 }; 285 bool has_async_transaction; 286 struct list_head async_todo; 287}; 288 289struct binder_ref_death { 290 /** 291 * @work: worklist element for death notifications 292 * (protected by inner_lock of the proc that 293 * this ref belongs to) 294 */ 295 struct binder_work work; 296 binder_uintptr_t cookie; 297}; 298 299/** 300 * struct binder_ref_data - binder_ref counts and id 301 * @debug_id: unique ID for the ref 302 * @desc: unique userspace handle for ref 303 * @strong: strong ref count (debugging only if not locked) 304 * @weak: weak ref count (debugging only if not locked) 305 * 306 * Structure to hold ref count and ref id information. Since 307 * the actual ref can only be accessed with a lock, this structure 308 * is used to return information about the ref to callers of 309 * ref inc/dec functions. 310 */ 311struct binder_ref_data { 312 int debug_id; 313 uint32_t desc; 314 int strong; 315 int weak; 316}; 317 318/** 319 * struct binder_ref - struct to track references on nodes 320 * @data: binder_ref_data containing id, handle, and current refcounts 321 * @rb_node_desc: node for lookup by @data.desc in proc's rb_tree 322 * @rb_node_node: node for lookup by @node in proc's rb_tree 323 * @node_entry: list entry for node->refs list in target node 324 * (protected by @node->lock) 325 * @proc: binder_proc containing ref 326 * @node: binder_node of target node. When cleaning up a 327 * ref for deletion in binder_cleanup_ref, a non-NULL 328 * @node indicates the node must be freed 329 * @death: pointer to death notification (ref_death) if requested 330 * (protected by @node->lock) 331 * 332 * Structure to track references from procA to target node (on procB). This 333 * structure is unsafe to access without holding @proc->outer_lock. 334 */ 335struct binder_ref { 336 /* Lookups needed: */ 337 /* node + proc => ref (transaction) */ 338 /* desc + proc => ref (transaction, inc/dec ref) */ 339 /* node => refs + procs (proc exit) */ 340 struct binder_ref_data data; 341 struct rb_node rb_node_desc; 342 struct rb_node rb_node_node; 343 struct hlist_node node_entry; 344 struct binder_proc *proc; 345 struct binder_node *node; 346 struct binder_ref_death *death; 347}; 348 349/** 350 * struct binder_proc - binder process bookkeeping 351 * @proc_node: element for binder_procs list 352 * @threads: rbtree of binder_threads in this proc 353 * (protected by @inner_lock) 354 * @nodes: rbtree of binder nodes associated with 355 * this proc ordered by node->ptr 356 * (protected by @inner_lock) 357 * @refs_by_desc: rbtree of refs ordered by ref->desc 358 * (protected by @outer_lock) 359 * @refs_by_node: rbtree of refs ordered by ref->node 360 * (protected by @outer_lock) 361 * @waiting_threads: threads currently waiting for proc work 362 * (protected by @inner_lock) 363 * @pid PID of group_leader of process 364 * (invariant after initialized) 365 * @tsk task_struct for group_leader of process 366 * (invariant after initialized) 367 * @cred struct cred associated with the `struct file` 368 * in binder_open() 369 * (invariant after initialized) 370 * @deferred_work_node: element for binder_deferred_list 371 * (protected by binder_deferred_lock) 372 * @deferred_work: bitmap of deferred work to perform 373 * (protected by binder_deferred_lock) 374 * @outstanding_txns: number of transactions to be transmitted before 375 * processes in freeze_wait are woken up 376 * (protected by @inner_lock) 377 * @is_dead: process is dead and awaiting free 378 * when outstanding transactions are cleaned up 379 * (protected by @inner_lock) 380 * @is_frozen: process is frozen and unable to service 381 * binder transactions 382 * (protected by @inner_lock) 383 * @sync_recv: process received sync transactions since last frozen 384 * bit 0: received sync transaction after being frozen 385 * bit 1: new pending sync transaction during freezing 386 * (protected by @inner_lock) 387 * @async_recv: process received async transactions since last frozen 388 * (protected by @inner_lock) 389 * @freeze_wait: waitqueue of processes waiting for all outstanding 390 * transactions to be processed 391 * (protected by @inner_lock) 392 * @todo: list of work for this process 393 * (protected by @inner_lock) 394 * @stats: per-process binder statistics 395 * (atomics, no lock needed) 396 * @delivered_death: list of delivered death notification 397 * (protected by @inner_lock) 398 * @max_threads: cap on number of binder threads 399 * (protected by @inner_lock) 400 * @requested_threads: number of binder threads requested but not 401 * yet started. In current implementation, can 402 * only be 0 or 1. 403 * (protected by @inner_lock) 404 * @requested_threads_started: number binder threads started 405 * (protected by @inner_lock) 406 * @tmp_ref: temporary reference to indicate proc is in use 407 * (protected by @inner_lock) 408 * @default_priority: default scheduler priority 409 * (invariant after initialized) 410 * @debugfs_entry: debugfs node 411 * @alloc: binder allocator bookkeeping 412 * @context: binder_context for this proc 413 * (invariant after initialized) 414 * @inner_lock: can nest under outer_lock and/or node lock 415 * @outer_lock: no nesting under innor or node lock 416 * Lock order: 1) outer, 2) node, 3) inner 417 * @binderfs_entry: process-specific binderfs log file 418 * @oneway_spam_detection_enabled: process enabled oneway spam detection 419 * or not 420 * 421 * Bookkeeping structure for binder processes 422 */ 423struct binder_proc { 424 struct hlist_node proc_node; 425 struct rb_root threads; 426 struct rb_root nodes; 427 struct rb_root refs_by_desc; 428 struct rb_root refs_by_node; 429 struct list_head waiting_threads; 430 int pid; 431 struct task_struct *tsk; 432 const struct cred *cred; 433 struct hlist_node deferred_work_node; 434 int deferred_work; 435 int outstanding_txns; 436 bool is_dead; 437 bool is_frozen; 438 bool sync_recv; 439 bool async_recv; 440 wait_queue_head_t freeze_wait; 441 442 struct list_head todo; 443 struct binder_stats stats; 444 struct list_head delivered_death; 445 int max_threads; 446 int requested_threads; 447 int requested_threads_started; 448 int tmp_ref; 449 long default_priority; 450 struct dentry *debugfs_entry; 451 struct binder_alloc alloc; 452 struct binder_context *context; 453 spinlock_t inner_lock; 454 spinlock_t outer_lock; 455 struct dentry *binderfs_entry; 456 bool oneway_spam_detection_enabled; 457}; 458 459/** 460 * struct binder_thread - binder thread bookkeeping 461 * @proc: binder process for this thread 462 * (invariant after initialization) 463 * @rb_node: element for proc->threads rbtree 464 * (protected by @proc->inner_lock) 465 * @waiting_thread_node: element for @proc->waiting_threads list 466 * (protected by @proc->inner_lock) 467 * @pid: PID for this thread 468 * (invariant after initialization) 469 * @looper: bitmap of looping state 470 * (only accessed by this thread) 471 * @looper_needs_return: looping thread needs to exit driver 472 * (no lock needed) 473 * @transaction_stack: stack of in-progress transactions for this thread 474 * (protected by @proc->inner_lock) 475 * @todo: list of work to do for this thread 476 * (protected by @proc->inner_lock) 477 * @process_todo: whether work in @todo should be processed 478 * (protected by @proc->inner_lock) 479 * @return_error: transaction errors reported by this thread 480 * (only accessed by this thread) 481 * @reply_error: transaction errors reported by target thread 482 * (protected by @proc->inner_lock) 483 * @ee: extended error information from this thread 484 * (protected by @proc->inner_lock) 485 * @wait: wait queue for thread work 486 * @stats: per-thread statistics 487 * (atomics, no lock needed) 488 * @tmp_ref: temporary reference to indicate thread is in use 489 * (atomic since @proc->inner_lock cannot 490 * always be acquired) 491 * @is_dead: thread is dead and awaiting free 492 * when outstanding transactions are cleaned up 493 * (protected by @proc->inner_lock) 494 * 495 * Bookkeeping structure for binder threads. 496 */ 497struct binder_thread { 498 struct binder_proc *proc; 499 struct rb_node rb_node; 500 struct list_head waiting_thread_node; 501 int pid; 502 int looper; /* only modified by this thread */ 503 bool looper_need_return; /* can be written by other thread */ 504 struct binder_transaction *transaction_stack; 505 struct list_head todo; 506 bool process_todo; 507 struct binder_error return_error; 508 struct binder_error reply_error; 509 struct binder_extended_error ee; 510 wait_queue_head_t wait; 511 struct binder_stats stats; 512 atomic_t tmp_ref; 513 bool is_dead; 514}; 515 516/** 517 * struct binder_txn_fd_fixup - transaction fd fixup list element 518 * @fixup_entry: list entry 519 * @file: struct file to be associated with new fd 520 * @offset: offset in buffer data to this fixup 521 * @target_fd: fd to use by the target to install @file 522 * 523 * List element for fd fixups in a transaction. Since file 524 * descriptors need to be allocated in the context of the 525 * target process, we pass each fd to be processed in this 526 * struct. 527 */ 528struct binder_txn_fd_fixup { 529 struct list_head fixup_entry; 530 struct file *file; 531 size_t offset; 532 int target_fd; 533}; 534 535struct binder_transaction { 536 int debug_id; 537 struct binder_work work; 538 struct binder_thread *from; 539 struct binder_transaction *from_parent; 540 struct binder_proc *to_proc; 541 struct binder_thread *to_thread; 542 struct binder_transaction *to_parent; 543 unsigned need_reply:1; 544 /* unsigned is_dead:1; */ /* not used at the moment */ 545 546 struct binder_buffer *buffer; 547 unsigned int code; 548 unsigned int flags; 549 long priority; 550 long saved_priority; 551 kuid_t sender_euid; 552 struct list_head fd_fixups; 553 binder_uintptr_t security_ctx; 554 /** 555 * @lock: protects @from, @to_proc, and @to_thread 556 * 557 * @from, @to_proc, and @to_thread can be set to NULL 558 * during thread teardown 559 */ 560 spinlock_t lock; 561}; 562 563/** 564 * struct binder_object - union of flat binder object types 565 * @hdr: generic object header 566 * @fbo: binder object (nodes and refs) 567 * @fdo: file descriptor object 568 * @bbo: binder buffer pointer 569 * @fdao: file descriptor array 570 * 571 * Used for type-independent object copies 572 */ 573struct binder_object { 574 union { 575 struct binder_object_header hdr; 576 struct flat_binder_object fbo; 577 struct binder_fd_object fdo; 578 struct binder_buffer_object bbo; 579 struct binder_fd_array_object fdao; 580 }; 581}; 582 583extern struct binder_transaction_log binder_transaction_log; 584extern struct binder_transaction_log binder_transaction_log_failed; 585#endif /* _LINUX_BINDER_INTERNAL_H */