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