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