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 #include "dbitmap.h" 18 19 struct binder_context { 20 struct binder_node *binder_context_mgr_node; 21 struct mutex context_mgr_node_lock; 22 kuid_t binder_context_mgr_uid; 23 const char *name; 24 }; 25 26 /** 27 * struct binder_device - information about a binder device node 28 * @hlist: list of binder devices (only used for devices requested via 29 * CONFIG_ANDROID_BINDER_DEVICES) 30 * @miscdev: information about a binder character device node 31 * @context: binder context information 32 * @binderfs_inode: This is the inode of the root dentry of the super block 33 * belonging to a binderfs mount. 34 */ 35 struct binder_device { 36 struct hlist_node hlist; 37 struct miscdevice miscdev; 38 struct binder_context context; 39 struct inode *binderfs_inode; 40 refcount_t ref; 41 }; 42 43 /** 44 * binderfs_mount_opts - mount options for binderfs 45 * @max: maximum number of allocatable binderfs binder devices 46 * @stats_mode: enable binder stats in binderfs. 47 */ 48 struct binderfs_mount_opts { 49 int max; 50 int stats_mode; 51 }; 52 53 /** 54 * binderfs_info - information about a binderfs mount 55 * @ipc_ns: The ipc namespace the binderfs mount belongs to. 56 * @control_dentry: This records the dentry of this binderfs mount 57 * binder-control device. 58 * @root_uid: uid that needs to be used when a new binder device is 59 * created. 60 * @root_gid: gid that needs to be used when a new binder device is 61 * created. 62 * @mount_opts: The mount options in use. 63 * @device_count: The current number of allocated binder devices. 64 * @proc_log_dir: Pointer to the directory dentry containing process-specific 65 * logs. 66 */ 67 struct binderfs_info { 68 struct ipc_namespace *ipc_ns; 69 struct dentry *control_dentry; 70 kuid_t root_uid; 71 kgid_t root_gid; 72 struct binderfs_mount_opts mount_opts; 73 int device_count; 74 struct dentry *proc_log_dir; 75 }; 76 77 extern const struct file_operations binder_fops; 78 79 extern char *binder_devices_param; 80 81 #ifdef CONFIG_ANDROID_BINDERFS 82 extern bool is_binderfs_device(const struct inode *inode); 83 extern struct dentry *binderfs_create_file(struct dentry *dir, const char *name, 84 const struct file_operations *fops, 85 void *data); 86 extern void binderfs_remove_file(struct dentry *dentry); 87 #else 88 static inline bool is_binderfs_device(const struct inode *inode) 89 { 90 return false; 91 } 92 static inline struct dentry *binderfs_create_file(struct dentry *dir, 93 const char *name, 94 const struct file_operations *fops, 95 void *data) 96 { 97 return NULL; 98 } 99 static inline void binderfs_remove_file(struct dentry *dentry) {} 100 #endif 101 102 #ifdef CONFIG_ANDROID_BINDERFS 103 extern int __init init_binderfs(void); 104 #else 105 static inline int __init init_binderfs(void) 106 { 107 return 0; 108 } 109 #endif 110 111 struct binder_debugfs_entry { 112 const char *name; 113 umode_t mode; 114 const struct file_operations *fops; 115 void *data; 116 }; 117 118 extern const struct binder_debugfs_entry binder_debugfs_entries[]; 119 120 #define binder_for_each_debugfs_entry(entry) \ 121 for ((entry) = binder_debugfs_entries; \ 122 (entry)->name; \ 123 (entry)++) 124 125 enum binder_stat_types { 126 BINDER_STAT_PROC, 127 BINDER_STAT_THREAD, 128 BINDER_STAT_NODE, 129 BINDER_STAT_REF, 130 BINDER_STAT_DEATH, 131 BINDER_STAT_TRANSACTION, 132 BINDER_STAT_TRANSACTION_COMPLETE, 133 BINDER_STAT_COUNT 134 }; 135 136 struct binder_stats { 137 atomic_t br[_IOC_NR(BR_TRANSACTION_PENDING_FROZEN) + 1]; 138 atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1]; 139 atomic_t obj_created[BINDER_STAT_COUNT]; 140 atomic_t obj_deleted[BINDER_STAT_COUNT]; 141 }; 142 143 /** 144 * struct binder_work - work enqueued on a worklist 145 * @entry: node enqueued on list 146 * @type: type of work to be performed 147 * 148 * There are separate work lists for proc, thread, and node (async). 149 */ 150 struct binder_work { 151 struct list_head entry; 152 153 enum binder_work_type { 154 BINDER_WORK_TRANSACTION = 1, 155 BINDER_WORK_TRANSACTION_COMPLETE, 156 BINDER_WORK_TRANSACTION_PENDING, 157 BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT, 158 BINDER_WORK_RETURN_ERROR, 159 BINDER_WORK_NODE, 160 BINDER_WORK_DEAD_BINDER, 161 BINDER_WORK_DEAD_BINDER_AND_CLEAR, 162 BINDER_WORK_CLEAR_DEATH_NOTIFICATION, 163 } type; 164 }; 165 166 struct binder_error { 167 struct binder_work work; 168 uint32_t cmd; 169 }; 170 171 /** 172 * struct binder_node - binder node bookkeeping 173 * @debug_id: unique ID for debugging 174 * (invariant after initialized) 175 * @lock: lock for node fields 176 * @work: worklist element for node work 177 * (protected by @proc->inner_lock) 178 * @rb_node: element for proc->nodes tree 179 * (protected by @proc->inner_lock) 180 * @dead_node: element for binder_dead_nodes list 181 * (protected by binder_dead_nodes_lock) 182 * @proc: binder_proc that owns this node 183 * (invariant after initialized) 184 * @refs: list of references on this node 185 * (protected by @lock) 186 * @internal_strong_refs: used to take strong references when 187 * initiating a transaction 188 * (protected by @proc->inner_lock if @proc 189 * and by @lock) 190 * @local_weak_refs: weak user refs from local process 191 * (protected by @proc->inner_lock if @proc 192 * and by @lock) 193 * @local_strong_refs: strong user refs from local process 194 * (protected by @proc->inner_lock if @proc 195 * and by @lock) 196 * @tmp_refs: temporary kernel refs 197 * (protected by @proc->inner_lock while @proc 198 * is valid, and by binder_dead_nodes_lock 199 * if @proc is NULL. During inc/dec and node release 200 * it is also protected by @lock to provide safety 201 * as the node dies and @proc becomes NULL) 202 * @ptr: userspace pointer for node 203 * (invariant, no lock needed) 204 * @cookie: userspace cookie for node 205 * (invariant, no lock needed) 206 * @has_strong_ref: userspace notified of strong ref 207 * (protected by @proc->inner_lock if @proc 208 * and by @lock) 209 * @pending_strong_ref: userspace has acked notification of strong ref 210 * (protected by @proc->inner_lock if @proc 211 * and by @lock) 212 * @has_weak_ref: userspace notified of weak ref 213 * (protected by @proc->inner_lock if @proc 214 * and by @lock) 215 * @pending_weak_ref: userspace has acked notification of weak ref 216 * (protected by @proc->inner_lock if @proc 217 * and by @lock) 218 * @has_async_transaction: async transaction to node in progress 219 * (protected by @lock) 220 * @accept_fds: file descriptor operations supported for node 221 * (invariant after initialized) 222 * @min_priority: minimum scheduling priority 223 * (invariant after initialized) 224 * @txn_security_ctx: require sender's security context 225 * (invariant after initialized) 226 * @async_todo: list of async work items 227 * (protected by @proc->inner_lock) 228 * 229 * Bookkeeping structure for binder nodes. 230 */ 231 struct binder_node { 232 int debug_id; 233 spinlock_t lock; 234 struct binder_work work; 235 union { 236 struct rb_node rb_node; 237 struct hlist_node dead_node; 238 }; 239 struct binder_proc *proc; 240 struct hlist_head refs; 241 int internal_strong_refs; 242 int local_weak_refs; 243 int local_strong_refs; 244 int tmp_refs; 245 binder_uintptr_t ptr; 246 binder_uintptr_t cookie; 247 struct { 248 /* 249 * bitfield elements protected by 250 * proc inner_lock 251 */ 252 u8 has_strong_ref:1; 253 u8 pending_strong_ref:1; 254 u8 has_weak_ref:1; 255 u8 pending_weak_ref:1; 256 }; 257 struct { 258 /* 259 * invariant after initialization 260 */ 261 u8 accept_fds:1; 262 u8 txn_security_ctx:1; 263 u8 min_priority; 264 }; 265 bool has_async_transaction; 266 struct list_head async_todo; 267 }; 268 269 struct binder_ref_death { 270 /** 271 * @work: worklist element for death notifications 272 * (protected by inner_lock of the proc that 273 * this ref belongs to) 274 */ 275 struct binder_work work; 276 binder_uintptr_t cookie; 277 }; 278 279 /** 280 * struct binder_ref_data - binder_ref counts and id 281 * @debug_id: unique ID for the ref 282 * @desc: unique userspace handle for ref 283 * @strong: strong ref count (debugging only if not locked) 284 * @weak: weak ref count (debugging only if not locked) 285 * 286 * Structure to hold ref count and ref id information. Since 287 * the actual ref can only be accessed with a lock, this structure 288 * is used to return information about the ref to callers of 289 * ref inc/dec functions. 290 */ 291 struct binder_ref_data { 292 int debug_id; 293 uint32_t desc; 294 int strong; 295 int weak; 296 }; 297 298 /** 299 * struct binder_ref - struct to track references on nodes 300 * @data: binder_ref_data containing id, handle, and current refcounts 301 * @rb_node_desc: node for lookup by @data.desc in proc's rb_tree 302 * @rb_node_node: node for lookup by @node in proc's rb_tree 303 * @node_entry: list entry for node->refs list in target node 304 * (protected by @node->lock) 305 * @proc: binder_proc containing ref 306 * @node: binder_node of target node. When cleaning up a 307 * ref for deletion in binder_cleanup_ref, a non-NULL 308 * @node indicates the node must be freed 309 * @death: pointer to death notification (ref_death) if requested 310 * (protected by @node->lock) 311 * 312 * Structure to track references from procA to target node (on procB). This 313 * structure is unsafe to access without holding @proc->outer_lock. 314 */ 315 struct binder_ref { 316 /* Lookups needed: */ 317 /* node + proc => ref (transaction) */ 318 /* desc + proc => ref (transaction, inc/dec ref) */ 319 /* node => refs + procs (proc exit) */ 320 struct binder_ref_data data; 321 struct rb_node rb_node_desc; 322 struct rb_node rb_node_node; 323 struct hlist_node node_entry; 324 struct binder_proc *proc; 325 struct binder_node *node; 326 struct binder_ref_death *death; 327 }; 328 329 /** 330 * struct binder_proc - binder process bookkeeping 331 * @proc_node: element for binder_procs list 332 * @threads: rbtree of binder_threads in this proc 333 * (protected by @inner_lock) 334 * @nodes: rbtree of binder nodes associated with 335 * this proc ordered by node->ptr 336 * (protected by @inner_lock) 337 * @refs_by_desc: rbtree of refs ordered by ref->desc 338 * (protected by @outer_lock) 339 * @refs_by_node: rbtree of refs ordered by ref->node 340 * (protected by @outer_lock) 341 * @waiting_threads: threads currently waiting for proc work 342 * (protected by @inner_lock) 343 * @pid PID of group_leader of process 344 * (invariant after initialized) 345 * @tsk task_struct for group_leader of process 346 * (invariant after initialized) 347 * @cred struct cred associated with the `struct file` 348 * in binder_open() 349 * (invariant after initialized) 350 * @deferred_work_node: element for binder_deferred_list 351 * (protected by binder_deferred_lock) 352 * @deferred_work: bitmap of deferred work to perform 353 * (protected by binder_deferred_lock) 354 * @outstanding_txns: number of transactions to be transmitted before 355 * processes in freeze_wait are woken up 356 * (protected by @inner_lock) 357 * @is_dead: process is dead and awaiting free 358 * when outstanding transactions are cleaned up 359 * (protected by @inner_lock) 360 * @is_frozen: process is frozen and unable to service 361 * binder transactions 362 * (protected by @inner_lock) 363 * @sync_recv: process received sync transactions since last frozen 364 * bit 0: received sync transaction after being frozen 365 * bit 1: new pending sync transaction during freezing 366 * (protected by @inner_lock) 367 * @async_recv: process received async transactions since last frozen 368 * (protected by @inner_lock) 369 * @freeze_wait: waitqueue of processes waiting for all outstanding 370 * transactions to be processed 371 * (protected by @inner_lock) 372 * @dmap dbitmap to manage available reference descriptors 373 * (protected by @outer_lock) 374 * @todo: list of work for this process 375 * (protected by @inner_lock) 376 * @stats: per-process binder statistics 377 * (atomics, no lock needed) 378 * @delivered_death: list of delivered death notification 379 * (protected by @inner_lock) 380 * @max_threads: cap on number of binder threads 381 * (protected by @inner_lock) 382 * @requested_threads: number of binder threads requested but not 383 * yet started. In current implementation, can 384 * only be 0 or 1. 385 * (protected by @inner_lock) 386 * @requested_threads_started: number binder threads started 387 * (protected by @inner_lock) 388 * @tmp_ref: temporary reference to indicate proc is in use 389 * (protected by @inner_lock) 390 * @default_priority: default scheduler priority 391 * (invariant after initialized) 392 * @debugfs_entry: debugfs node 393 * @alloc: binder allocator bookkeeping 394 * @context: binder_context for this proc 395 * (invariant after initialized) 396 * @inner_lock: can nest under outer_lock and/or node lock 397 * @outer_lock: no nesting under innor or node lock 398 * Lock order: 1) outer, 2) node, 3) inner 399 * @binderfs_entry: process-specific binderfs log file 400 * @oneway_spam_detection_enabled: process enabled oneway spam detection 401 * or not 402 * 403 * Bookkeeping structure for binder processes 404 */ 405 struct binder_proc { 406 struct hlist_node proc_node; 407 struct rb_root threads; 408 struct rb_root nodes; 409 struct rb_root refs_by_desc; 410 struct rb_root refs_by_node; 411 struct list_head waiting_threads; 412 int pid; 413 struct task_struct *tsk; 414 const struct cred *cred; 415 struct hlist_node deferred_work_node; 416 int deferred_work; 417 int outstanding_txns; 418 bool is_dead; 419 bool is_frozen; 420 bool sync_recv; 421 bool async_recv; 422 wait_queue_head_t freeze_wait; 423 struct dbitmap dmap; 424 struct list_head todo; 425 struct binder_stats stats; 426 struct list_head delivered_death; 427 u32 max_threads; 428 int requested_threads; 429 int requested_threads_started; 430 int tmp_ref; 431 long default_priority; 432 struct dentry *debugfs_entry; 433 struct binder_alloc alloc; 434 struct binder_context *context; 435 spinlock_t inner_lock; 436 spinlock_t outer_lock; 437 struct dentry *binderfs_entry; 438 bool oneway_spam_detection_enabled; 439 }; 440 441 /** 442 * struct binder_thread - binder thread bookkeeping 443 * @proc: binder process for this thread 444 * (invariant after initialization) 445 * @rb_node: element for proc->threads rbtree 446 * (protected by @proc->inner_lock) 447 * @waiting_thread_node: element for @proc->waiting_threads list 448 * (protected by @proc->inner_lock) 449 * @pid: PID for this thread 450 * (invariant after initialization) 451 * @looper: bitmap of looping state 452 * (only accessed by this thread) 453 * @looper_needs_return: looping thread needs to exit driver 454 * (no lock needed) 455 * @transaction_stack: stack of in-progress transactions for this thread 456 * (protected by @proc->inner_lock) 457 * @todo: list of work to do for this thread 458 * (protected by @proc->inner_lock) 459 * @process_todo: whether work in @todo should be processed 460 * (protected by @proc->inner_lock) 461 * @return_error: transaction errors reported by this thread 462 * (only accessed by this thread) 463 * @reply_error: transaction errors reported by target thread 464 * (protected by @proc->inner_lock) 465 * @ee: extended error information from this thread 466 * (protected by @proc->inner_lock) 467 * @wait: wait queue for thread work 468 * @stats: per-thread statistics 469 * (atomics, no lock needed) 470 * @tmp_ref: temporary reference to indicate thread is in use 471 * (atomic since @proc->inner_lock cannot 472 * always be acquired) 473 * @is_dead: thread is dead and awaiting free 474 * when outstanding transactions are cleaned up 475 * (protected by @proc->inner_lock) 476 * 477 * Bookkeeping structure for binder threads. 478 */ 479 struct binder_thread { 480 struct binder_proc *proc; 481 struct rb_node rb_node; 482 struct list_head waiting_thread_node; 483 int pid; 484 int looper; /* only modified by this thread */ 485 bool looper_need_return; /* can be written by other thread */ 486 struct binder_transaction *transaction_stack; 487 struct list_head todo; 488 bool process_todo; 489 struct binder_error return_error; 490 struct binder_error reply_error; 491 struct binder_extended_error ee; 492 wait_queue_head_t wait; 493 struct binder_stats stats; 494 atomic_t tmp_ref; 495 bool is_dead; 496 }; 497 498 /** 499 * struct binder_txn_fd_fixup - transaction fd fixup list element 500 * @fixup_entry: list entry 501 * @file: struct file to be associated with new fd 502 * @offset: offset in buffer data to this fixup 503 * @target_fd: fd to use by the target to install @file 504 * 505 * List element for fd fixups in a transaction. Since file 506 * descriptors need to be allocated in the context of the 507 * target process, we pass each fd to be processed in this 508 * struct. 509 */ 510 struct binder_txn_fd_fixup { 511 struct list_head fixup_entry; 512 struct file *file; 513 size_t offset; 514 int target_fd; 515 }; 516 517 struct binder_transaction { 518 int debug_id; 519 struct binder_work work; 520 struct binder_thread *from; 521 pid_t from_pid; 522 pid_t from_tid; 523 struct binder_transaction *from_parent; 524 struct binder_proc *to_proc; 525 struct binder_thread *to_thread; 526 struct binder_transaction *to_parent; 527 unsigned need_reply:1; 528 /* unsigned is_dead:1; */ /* not used at the moment */ 529 530 struct binder_buffer *buffer; 531 unsigned int code; 532 unsigned int flags; 533 long priority; 534 long saved_priority; 535 kuid_t sender_euid; 536 ktime_t start_time; 537 struct list_head fd_fixups; 538 binder_uintptr_t security_ctx; 539 /** 540 * @lock: protects @from, @to_proc, and @to_thread 541 * 542 * @from, @to_proc, and @to_thread can be set to NULL 543 * during thread teardown 544 */ 545 spinlock_t lock; 546 }; 547 548 /** 549 * struct binder_object - union of flat binder object types 550 * @hdr: generic object header 551 * @fbo: binder object (nodes and refs) 552 * @fdo: file descriptor object 553 * @bbo: binder buffer pointer 554 * @fdao: file descriptor array 555 * 556 * Used for type-independent object copies 557 */ 558 struct binder_object { 559 union { 560 struct binder_object_header hdr; 561 struct flat_binder_object fbo; 562 struct binder_fd_object fdo; 563 struct binder_buffer_object bbo; 564 struct binder_fd_array_object fdao; 565 }; 566 }; 567 568 #endif /* _LINUX_BINDER_INTERNAL_H */ 569