1#ifndef IO_URING_TYPES_H 2#define IO_URING_TYPES_H 3 4#include <linux/blkdev.h> 5#include <linux/hashtable.h> 6#include <linux/task_work.h> 7#include <linux/bitmap.h> 8#include <linux/llist.h> 9#include <uapi/linux/io_uring.h> 10 11enum { 12 /* 13 * A hint to not wake right away but delay until there are enough of 14 * tw's queued to match the number of CQEs the task is waiting for. 15 * 16 * Must not be used with requests generating more than one CQE. 17 * It's also ignored unless IORING_SETUP_DEFER_TASKRUN is set. 18 */ 19 IOU_F_TWQ_LAZY_WAKE = 1, 20}; 21 22enum io_uring_cmd_flags { 23 IO_URING_F_COMPLETE_DEFER = 1, 24 IO_URING_F_UNLOCKED = 2, 25 /* the request is executed from poll, it should not be freed */ 26 IO_URING_F_MULTISHOT = 4, 27 /* executed by io-wq */ 28 IO_URING_F_IOWQ = 8, 29 /* int's last bit, sign checks are usually faster than a bit test */ 30 IO_URING_F_NONBLOCK = INT_MIN, 31 32 /* ctx state flags, for URING_CMD */ 33 IO_URING_F_SQE128 = (1 << 8), 34 IO_URING_F_CQE32 = (1 << 9), 35 IO_URING_F_IOPOLL = (1 << 10), 36 37 /* set when uring wants to cancel a previously issued command */ 38 IO_URING_F_CANCEL = (1 << 11), 39 IO_URING_F_COMPAT = (1 << 12), 40}; 41 42struct io_wq_work_node { 43 struct io_wq_work_node *next; 44}; 45 46struct io_wq_work_list { 47 struct io_wq_work_node *first; 48 struct io_wq_work_node *last; 49}; 50 51struct io_wq_work { 52 struct io_wq_work_node list; 53 unsigned flags; 54 /* place it here instead of io_kiocb as it fills padding and saves 4B */ 55 int cancel_seq; 56}; 57 58struct io_fixed_file { 59 /* file * with additional FFS_* flags */ 60 unsigned long file_ptr; 61}; 62 63struct io_file_table { 64 struct io_fixed_file *files; 65 unsigned long *bitmap; 66 unsigned int alloc_hint; 67}; 68 69struct io_hash_bucket { 70 spinlock_t lock; 71 struct hlist_head list; 72} ____cacheline_aligned_in_smp; 73 74struct io_hash_table { 75 struct io_hash_bucket *hbs; 76 unsigned hash_bits; 77}; 78 79/* 80 * Arbitrary limit, can be raised if need be 81 */ 82#define IO_RINGFD_REG_MAX 16 83 84struct io_uring_task { 85 /* submission side */ 86 int cached_refs; 87 const struct io_ring_ctx *last; 88 struct io_wq *io_wq; 89 struct file *registered_rings[IO_RINGFD_REG_MAX]; 90 91 struct xarray xa; 92 struct wait_queue_head wait; 93 atomic_t in_cancel; 94 atomic_t inflight_tracked; 95 struct percpu_counter inflight; 96 97 struct { /* task_work */ 98 struct llist_head task_list; 99 struct callback_head task_work; 100 } ____cacheline_aligned_in_smp; 101}; 102 103struct io_uring { 104 u32 head; 105 u32 tail; 106}; 107 108/* 109 * This data is shared with the application through the mmap at offsets 110 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING. 111 * 112 * The offsets to the member fields are published through struct 113 * io_sqring_offsets when calling io_uring_setup. 114 */ 115struct io_rings { 116 /* 117 * Head and tail offsets into the ring; the offsets need to be 118 * masked to get valid indices. 119 * 120 * The kernel controls head of the sq ring and the tail of the cq ring, 121 * and the application controls tail of the sq ring and the head of the 122 * cq ring. 123 */ 124 struct io_uring sq, cq; 125 /* 126 * Bitmasks to apply to head and tail offsets (constant, equals 127 * ring_entries - 1) 128 */ 129 u32 sq_ring_mask, cq_ring_mask; 130 /* Ring sizes (constant, power of 2) */ 131 u32 sq_ring_entries, cq_ring_entries; 132 /* 133 * Number of invalid entries dropped by the kernel due to 134 * invalid index stored in array 135 * 136 * Written by the kernel, shouldn't be modified by the 137 * application (i.e. get number of "new events" by comparing to 138 * cached value). 139 * 140 * After a new SQ head value was read by the application this 141 * counter includes all submissions that were dropped reaching 142 * the new SQ head (and possibly more). 143 */ 144 u32 sq_dropped; 145 /* 146 * Runtime SQ flags 147 * 148 * Written by the kernel, shouldn't be modified by the 149 * application. 150 * 151 * The application needs a full memory barrier before checking 152 * for IORING_SQ_NEED_WAKEUP after updating the sq tail. 153 */ 154 atomic_t sq_flags; 155 /* 156 * Runtime CQ flags 157 * 158 * Written by the application, shouldn't be modified by the 159 * kernel. 160 */ 161 u32 cq_flags; 162 /* 163 * Number of completion events lost because the queue was full; 164 * this should be avoided by the application by making sure 165 * there are not more requests pending than there is space in 166 * the completion queue. 167 * 168 * Written by the kernel, shouldn't be modified by the 169 * application (i.e. get number of "new events" by comparing to 170 * cached value). 171 * 172 * As completion events come in out of order this counter is not 173 * ordered with any other data. 174 */ 175 u32 cq_overflow; 176 /* 177 * Ring buffer of completion events. 178 * 179 * The kernel writes completion events fresh every time they are 180 * produced, so the application is allowed to modify pending 181 * entries. 182 */ 183 struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp; 184}; 185 186struct io_restriction { 187 DECLARE_BITMAP(register_op, IORING_REGISTER_LAST); 188 DECLARE_BITMAP(sqe_op, IORING_OP_LAST); 189 u8 sqe_flags_allowed; 190 u8 sqe_flags_required; 191 bool registered; 192}; 193 194struct io_submit_link { 195 struct io_kiocb *head; 196 struct io_kiocb *last; 197}; 198 199struct io_submit_state { 200 /* inline/task_work completion list, under ->uring_lock */ 201 struct io_wq_work_node free_list; 202 /* batch completion logic */ 203 struct io_wq_work_list compl_reqs; 204 struct io_submit_link link; 205 206 bool plug_started; 207 bool need_plug; 208 unsigned short submit_nr; 209 unsigned int cqes_count; 210 struct blk_plug plug; 211}; 212 213struct io_ev_fd { 214 struct eventfd_ctx *cq_ev_fd; 215 unsigned int eventfd_async: 1; 216 struct rcu_head rcu; 217 atomic_t refs; 218 atomic_t ops; 219}; 220 221struct io_alloc_cache { 222 struct io_wq_work_node list; 223 unsigned int nr_cached; 224 unsigned int max_cached; 225 size_t elem_size; 226}; 227 228struct io_ring_ctx { 229 /* const or read-mostly hot data */ 230 struct { 231 unsigned int flags; 232 unsigned int drain_next: 1; 233 unsigned int restricted: 1; 234 unsigned int off_timeout_used: 1; 235 unsigned int drain_active: 1; 236 unsigned int has_evfd: 1; 237 /* all CQEs should be posted only by the submitter task */ 238 unsigned int task_complete: 1; 239 unsigned int lockless_cq: 1; 240 unsigned int syscall_iopoll: 1; 241 unsigned int poll_activated: 1; 242 unsigned int drain_disabled: 1; 243 unsigned int compat: 1; 244 unsigned int iowq_limits_set : 1; 245 246 struct task_struct *submitter_task; 247 struct io_rings *rings; 248 struct percpu_ref refs; 249 250 enum task_work_notify_mode notify_method; 251 unsigned sq_thread_idle; 252 } ____cacheline_aligned_in_smp; 253 254 /* submission data */ 255 struct { 256 struct mutex uring_lock; 257 258 /* 259 * Ring buffer of indices into array of io_uring_sqe, which is 260 * mmapped by the application using the IORING_OFF_SQES offset. 261 * 262 * This indirection could e.g. be used to assign fixed 263 * io_uring_sqe entries to operations and only submit them to 264 * the queue when needed. 265 * 266 * The kernel modifies neither the indices array nor the entries 267 * array. 268 */ 269 u32 *sq_array; 270 struct io_uring_sqe *sq_sqes; 271 unsigned cached_sq_head; 272 unsigned sq_entries; 273 274 /* 275 * Fixed resources fast path, should be accessed only under 276 * uring_lock, and updated through io_uring_register(2) 277 */ 278 struct io_rsrc_node *rsrc_node; 279 atomic_t cancel_seq; 280 281 /* 282 * ->iopoll_list is protected by the ctx->uring_lock for 283 * io_uring instances that don't use IORING_SETUP_SQPOLL. 284 * For SQPOLL, only the single threaded io_sq_thread() will 285 * manipulate the list, hence no extra locking is needed there. 286 */ 287 bool poll_multi_queue; 288 struct io_wq_work_list iopoll_list; 289 290 struct io_file_table file_table; 291 struct io_mapped_ubuf **user_bufs; 292 unsigned nr_user_files; 293 unsigned nr_user_bufs; 294 295 struct io_submit_state submit_state; 296 297 struct xarray io_bl_xa; 298 299 struct io_hash_table cancel_table_locked; 300 struct io_alloc_cache apoll_cache; 301 struct io_alloc_cache netmsg_cache; 302 303 /* 304 * Any cancelable uring_cmd is added to this list in 305 * ->uring_cmd() by io_uring_cmd_insert_cancelable() 306 */ 307 struct hlist_head cancelable_uring_cmd; 308 } ____cacheline_aligned_in_smp; 309 310 struct { 311 /* 312 * We cache a range of free CQEs we can use, once exhausted it 313 * should go through a slower range setup, see __io_get_cqe() 314 */ 315 struct io_uring_cqe *cqe_cached; 316 struct io_uring_cqe *cqe_sentinel; 317 318 unsigned cached_cq_tail; 319 unsigned cq_entries; 320 struct io_ev_fd __rcu *io_ev_fd; 321 unsigned cq_extra; 322 } ____cacheline_aligned_in_smp; 323 324 /* 325 * task_work and async notification delivery cacheline. Expected to 326 * regularly bounce b/w CPUs. 327 */ 328 struct { 329 struct llist_head work_llist; 330 unsigned long check_cq; 331 atomic_t cq_wait_nr; 332 atomic_t cq_timeouts; 333 struct wait_queue_head cq_wait; 334 } ____cacheline_aligned_in_smp; 335 336 /* timeouts */ 337 struct { 338 spinlock_t timeout_lock; 339 struct list_head timeout_list; 340 struct list_head ltimeout_list; 341 unsigned cq_last_tm_flush; 342 } ____cacheline_aligned_in_smp; 343 344 struct io_uring_cqe completion_cqes[16]; 345 346 spinlock_t completion_lock; 347 348 /* IRQ completion list, under ->completion_lock */ 349 unsigned int locked_free_nr; 350 struct io_wq_work_list locked_free_list; 351 352 struct list_head io_buffers_comp; 353 struct list_head cq_overflow_list; 354 struct io_hash_table cancel_table; 355 356 struct hlist_head waitid_list; 357 358#ifdef CONFIG_FUTEX 359 struct hlist_head futex_list; 360 struct io_alloc_cache futex_cache; 361#endif 362 363 const struct cred *sq_creds; /* cred used for __io_sq_thread() */ 364 struct io_sq_data *sq_data; /* if using sq thread polling */ 365 366 struct wait_queue_head sqo_sq_wait; 367 struct list_head sqd_list; 368 369 unsigned int file_alloc_start; 370 unsigned int file_alloc_end; 371 372 struct list_head io_buffers_cache; 373 374 /* deferred free list, protected by ->uring_lock */ 375 struct hlist_head io_buf_list; 376 377 /* Keep this last, we don't need it for the fast path */ 378 struct wait_queue_head poll_wq; 379 struct io_restriction restrictions; 380 381 /* slow path rsrc auxilary data, used by update/register */ 382 struct io_mapped_ubuf *dummy_ubuf; 383 struct io_rsrc_data *file_data; 384 struct io_rsrc_data *buf_data; 385 386 /* protected by ->uring_lock */ 387 struct list_head rsrc_ref_list; 388 struct io_alloc_cache rsrc_node_cache; 389 struct wait_queue_head rsrc_quiesce_wq; 390 unsigned rsrc_quiesce; 391 392 u32 pers_next; 393 struct xarray personalities; 394 395 /* hashed buffered write serialization */ 396 struct io_wq_hash *hash_map; 397 398 /* Only used for accounting purposes */ 399 struct user_struct *user; 400 struct mm_struct *mm_account; 401 402 /* ctx exit and cancelation */ 403 struct llist_head fallback_llist; 404 struct delayed_work fallback_work; 405 struct work_struct exit_work; 406 struct list_head tctx_list; 407 struct completion ref_comp; 408 409 /* io-wq management, e.g. thread count */ 410 u32 iowq_limits[2]; 411 412 struct callback_head poll_wq_task_work; 413 struct list_head defer_list; 414 415#ifdef CONFIG_NET_RX_BUSY_POLL 416 struct list_head napi_list; /* track busy poll napi_id */ 417 spinlock_t napi_lock; /* napi_list lock */ 418 419 /* napi busy poll default timeout */ 420 unsigned int napi_busy_poll_to; 421 bool napi_prefer_busy_poll; 422 bool napi_enabled; 423 424 DECLARE_HASHTABLE(napi_ht, 4); 425#endif 426 427 /* protected by ->completion_lock */ 428 unsigned evfd_last_cq_tail; 429 430 /* 431 * If IORING_SETUP_NO_MMAP is used, then the below holds 432 * the gup'ed pages for the two rings, and the sqes. 433 */ 434 unsigned short n_ring_pages; 435 unsigned short n_sqe_pages; 436 struct page **ring_pages; 437 struct page **sqe_pages; 438}; 439 440struct io_tw_state { 441 /* ->uring_lock is taken, callbacks can use io_tw_lock to lock it */ 442 bool locked; 443}; 444 445enum { 446 REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT, 447 REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT, 448 REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT, 449 REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT, 450 REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT, 451 REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT, 452 REQ_F_CQE_SKIP_BIT = IOSQE_CQE_SKIP_SUCCESS_BIT, 453 454 /* first byte is taken by user flags, shift it to not overlap */ 455 REQ_F_FAIL_BIT = 8, 456 REQ_F_INFLIGHT_BIT, 457 REQ_F_CUR_POS_BIT, 458 REQ_F_NOWAIT_BIT, 459 REQ_F_LINK_TIMEOUT_BIT, 460 REQ_F_NEED_CLEANUP_BIT, 461 REQ_F_POLLED_BIT, 462 REQ_F_BUFFER_SELECTED_BIT, 463 REQ_F_BUFFER_RING_BIT, 464 REQ_F_REISSUE_BIT, 465 REQ_F_CREDS_BIT, 466 REQ_F_REFCOUNT_BIT, 467 REQ_F_ARM_LTIMEOUT_BIT, 468 REQ_F_ASYNC_DATA_BIT, 469 REQ_F_SKIP_LINK_CQES_BIT, 470 REQ_F_SINGLE_POLL_BIT, 471 REQ_F_DOUBLE_POLL_BIT, 472 REQ_F_APOLL_MULTISHOT_BIT, 473 REQ_F_CLEAR_POLLIN_BIT, 474 REQ_F_HASH_LOCKED_BIT, 475 /* keep async read/write and isreg together and in order */ 476 REQ_F_SUPPORT_NOWAIT_BIT, 477 REQ_F_ISREG_BIT, 478 REQ_F_POLL_NO_LAZY_BIT, 479 REQ_F_CANCEL_SEQ_BIT, 480 REQ_F_CAN_POLL_BIT, 481 REQ_F_BL_EMPTY_BIT, 482 REQ_F_BL_NO_RECYCLE_BIT, 483 484 /* not a real bit, just to check we're not overflowing the space */ 485 __REQ_F_LAST_BIT, 486}; 487 488typedef u64 __bitwise io_req_flags_t; 489#define IO_REQ_FLAG(bitno) ((__force io_req_flags_t) BIT_ULL((bitno))) 490 491enum { 492 /* ctx owns file */ 493 REQ_F_FIXED_FILE = IO_REQ_FLAG(REQ_F_FIXED_FILE_BIT), 494 /* drain existing IO first */ 495 REQ_F_IO_DRAIN = IO_REQ_FLAG(REQ_F_IO_DRAIN_BIT), 496 /* linked sqes */ 497 REQ_F_LINK = IO_REQ_FLAG(REQ_F_LINK_BIT), 498 /* doesn't sever on completion < 0 */ 499 REQ_F_HARDLINK = IO_REQ_FLAG(REQ_F_HARDLINK_BIT), 500 /* IOSQE_ASYNC */ 501 REQ_F_FORCE_ASYNC = IO_REQ_FLAG(REQ_F_FORCE_ASYNC_BIT), 502 /* IOSQE_BUFFER_SELECT */ 503 REQ_F_BUFFER_SELECT = IO_REQ_FLAG(REQ_F_BUFFER_SELECT_BIT), 504 /* IOSQE_CQE_SKIP_SUCCESS */ 505 REQ_F_CQE_SKIP = IO_REQ_FLAG(REQ_F_CQE_SKIP_BIT), 506 507 /* fail rest of links */ 508 REQ_F_FAIL = IO_REQ_FLAG(REQ_F_FAIL_BIT), 509 /* on inflight list, should be cancelled and waited on exit reliably */ 510 REQ_F_INFLIGHT = IO_REQ_FLAG(REQ_F_INFLIGHT_BIT), 511 /* read/write uses file position */ 512 REQ_F_CUR_POS = IO_REQ_FLAG(REQ_F_CUR_POS_BIT), 513 /* must not punt to workers */ 514 REQ_F_NOWAIT = IO_REQ_FLAG(REQ_F_NOWAIT_BIT), 515 /* has or had linked timeout */ 516 REQ_F_LINK_TIMEOUT = IO_REQ_FLAG(REQ_F_LINK_TIMEOUT_BIT), 517 /* needs cleanup */ 518 REQ_F_NEED_CLEANUP = IO_REQ_FLAG(REQ_F_NEED_CLEANUP_BIT), 519 /* already went through poll handler */ 520 REQ_F_POLLED = IO_REQ_FLAG(REQ_F_POLLED_BIT), 521 /* buffer already selected */ 522 REQ_F_BUFFER_SELECTED = IO_REQ_FLAG(REQ_F_BUFFER_SELECTED_BIT), 523 /* buffer selected from ring, needs commit */ 524 REQ_F_BUFFER_RING = IO_REQ_FLAG(REQ_F_BUFFER_RING_BIT), 525 /* caller should reissue async */ 526 REQ_F_REISSUE = IO_REQ_FLAG(REQ_F_REISSUE_BIT), 527 /* supports async reads/writes */ 528 REQ_F_SUPPORT_NOWAIT = IO_REQ_FLAG(REQ_F_SUPPORT_NOWAIT_BIT), 529 /* regular file */ 530 REQ_F_ISREG = IO_REQ_FLAG(REQ_F_ISREG_BIT), 531 /* has creds assigned */ 532 REQ_F_CREDS = IO_REQ_FLAG(REQ_F_CREDS_BIT), 533 /* skip refcounting if not set */ 534 REQ_F_REFCOUNT = IO_REQ_FLAG(REQ_F_REFCOUNT_BIT), 535 /* there is a linked timeout that has to be armed */ 536 REQ_F_ARM_LTIMEOUT = IO_REQ_FLAG(REQ_F_ARM_LTIMEOUT_BIT), 537 /* ->async_data allocated */ 538 REQ_F_ASYNC_DATA = IO_REQ_FLAG(REQ_F_ASYNC_DATA_BIT), 539 /* don't post CQEs while failing linked requests */ 540 REQ_F_SKIP_LINK_CQES = IO_REQ_FLAG(REQ_F_SKIP_LINK_CQES_BIT), 541 /* single poll may be active */ 542 REQ_F_SINGLE_POLL = IO_REQ_FLAG(REQ_F_SINGLE_POLL_BIT), 543 /* double poll may active */ 544 REQ_F_DOUBLE_POLL = IO_REQ_FLAG(REQ_F_DOUBLE_POLL_BIT), 545 /* fast poll multishot mode */ 546 REQ_F_APOLL_MULTISHOT = IO_REQ_FLAG(REQ_F_APOLL_MULTISHOT_BIT), 547 /* recvmsg special flag, clear EPOLLIN */ 548 REQ_F_CLEAR_POLLIN = IO_REQ_FLAG(REQ_F_CLEAR_POLLIN_BIT), 549 /* hashed into ->cancel_hash_locked, protected by ->uring_lock */ 550 REQ_F_HASH_LOCKED = IO_REQ_FLAG(REQ_F_HASH_LOCKED_BIT), 551 /* don't use lazy poll wake for this request */ 552 REQ_F_POLL_NO_LAZY = IO_REQ_FLAG(REQ_F_POLL_NO_LAZY_BIT), 553 /* cancel sequence is set and valid */ 554 REQ_F_CANCEL_SEQ = IO_REQ_FLAG(REQ_F_CANCEL_SEQ_BIT), 555 /* file is pollable */ 556 REQ_F_CAN_POLL = IO_REQ_FLAG(REQ_F_CAN_POLL_BIT), 557 /* buffer list was empty after selection of buffer */ 558 REQ_F_BL_EMPTY = IO_REQ_FLAG(REQ_F_BL_EMPTY_BIT), 559 /* don't recycle provided buffers for this request */ 560 REQ_F_BL_NO_RECYCLE = IO_REQ_FLAG(REQ_F_BL_NO_RECYCLE_BIT), 561}; 562 563typedef void (*io_req_tw_func_t)(struct io_kiocb *req, struct io_tw_state *ts); 564 565struct io_task_work { 566 struct llist_node node; 567 io_req_tw_func_t func; 568}; 569 570struct io_cqe { 571 __u64 user_data; 572 __s32 res; 573 /* fd initially, then cflags for completion */ 574 union { 575 __u32 flags; 576 int fd; 577 }; 578}; 579 580/* 581 * Each request type overlays its private data structure on top of this one. 582 * They must not exceed this one in size. 583 */ 584struct io_cmd_data { 585 struct file *file; 586 /* each command gets 56 bytes of data */ 587 __u8 data[56]; 588}; 589 590static inline void io_kiocb_cmd_sz_check(size_t cmd_sz) 591{ 592 BUILD_BUG_ON(cmd_sz > sizeof(struct io_cmd_data)); 593} 594#define io_kiocb_to_cmd(req, cmd_type) ( \ 595 io_kiocb_cmd_sz_check(sizeof(cmd_type)) , \ 596 ((cmd_type *)&(req)->cmd) \ 597) 598#define cmd_to_io_kiocb(ptr) ((struct io_kiocb *) ptr) 599 600struct io_kiocb { 601 union { 602 /* 603 * NOTE! Each of the io_kiocb union members has the file pointer 604 * as the first entry in their struct definition. So you can 605 * access the file pointer through any of the sub-structs, 606 * or directly as just 'file' in this struct. 607 */ 608 struct file *file; 609 struct io_cmd_data cmd; 610 }; 611 612 u8 opcode; 613 /* polled IO has completed */ 614 u8 iopoll_completed; 615 /* 616 * Can be either a fixed buffer index, or used with provided buffers. 617 * For the latter, before issue it points to the buffer group ID, 618 * and after selection it points to the buffer ID itself. 619 */ 620 u16 buf_index; 621 622 unsigned nr_tw; 623 624 /* REQ_F_* flags */ 625 io_req_flags_t flags; 626 627 struct io_cqe cqe; 628 629 struct io_ring_ctx *ctx; 630 struct task_struct *task; 631 632 union { 633 /* store used ubuf, so we can prevent reloading */ 634 struct io_mapped_ubuf *imu; 635 636 /* stores selected buf, valid IFF REQ_F_BUFFER_SELECTED is set */ 637 struct io_buffer *kbuf; 638 639 /* 640 * stores buffer ID for ring provided buffers, valid IFF 641 * REQ_F_BUFFER_RING is set. 642 */ 643 struct io_buffer_list *buf_list; 644 }; 645 646 union { 647 /* used by request caches, completion batching and iopoll */ 648 struct io_wq_work_node comp_list; 649 /* cache ->apoll->events */ 650 __poll_t apoll_events; 651 }; 652 653 struct io_rsrc_node *rsrc_node; 654 655 atomic_t refs; 656 atomic_t poll_refs; 657 struct io_task_work io_task_work; 658 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */ 659 struct hlist_node hash_node; 660 /* internal polling, see IORING_FEAT_FAST_POLL */ 661 struct async_poll *apoll; 662 /* opcode allocated if it needs to store data for async defer */ 663 void *async_data; 664 /* linked requests, IFF REQ_F_HARDLINK or REQ_F_LINK are set */ 665 struct io_kiocb *link; 666 /* custom credentials, valid IFF REQ_F_CREDS is set */ 667 const struct cred *creds; 668 struct io_wq_work work; 669 670 struct { 671 u64 extra1; 672 u64 extra2; 673 } big_cqe; 674}; 675 676struct io_overflow_cqe { 677 struct list_head list; 678 struct io_uring_cqe cqe; 679}; 680 681#endif 682