util/aio-posix.h

   1 /*
   2  * AioContext POSIX event loop implementation internal APIs
   3  *
   4  * Copyright IBM, Corp. 2008
   5  * Copyright Red Hat, Inc. 2020
   6  *
   7  * Authors:
   8  *  Anthony Liguori   <aliguori@us.ibm.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2.  See
  11  * the COPYING file in the top-level directory.
  12  *
  13  * Contributions after 2012-01-13 are licensed under the terms of the
  14  * GNU GPL, version 2 or (at your option) any later version.
  15  */
  16
  17 #ifndef AIO_POSIX_H
  18 #define AIO_POSIX_H
  19
  20 #include "block/aio.h"
  21
  22 struct AioHandler {
  23     GPollFD pfd;
  24     IOHandler *io_read;
  25     IOHandler *io_write;
  26     AioPollFn *io_poll;
  27     IOHandler *io_poll_ready;
  28     IOHandler *io_poll_begin;
  29     IOHandler *io_poll_end;
  30     void *opaque;
  31     QLIST_ENTRY(AioHandler) node;
  32     QLIST_ENTRY(AioHandler) node_ready; /* only used during aio_poll() */
  33     QLIST_ENTRY(AioHandler) node_deleted;
  34     QLIST_ENTRY(AioHandler) node_poll;
  35 #ifdef CONFIG_LINUX_IO_URING
  36     QSLIST_ENTRY(AioHandler) node_submitted;
  37     unsigned flags; /* see fdmon-io_uring.c */
  38 #endif
  39     int64_t poll_idle_timeout; /* when to stop userspace polling */
  40     bool poll_ready; /* has polling detected an event? */
  41 };
  42
  43 /* Add a handler to a ready list */
  44 void aio_add_ready_handler(AioHandlerList *ready_list, AioHandler *node,
  45                            int revents);
  46
  47 extern const FDMonOps fdmon_poll_ops;
  48
  49 #ifdef CONFIG_EPOLL_CREATE1
  50 bool fdmon_epoll_try_upgrade(AioContext *ctx, unsigned npfd);
  51 void fdmon_epoll_setup(AioContext *ctx);
  52 void fdmon_epoll_disable(AioContext *ctx);
  53 #else
  54 static inline bool fdmon_epoll_try_upgrade(AioContext *ctx, unsigned npfd)
  55 {
  56     return false;
  57 }
  58
  59 static inline void fdmon_epoll_setup(AioContext *ctx)
  60 {
  61 }
  62
  63 static inline void fdmon_epoll_disable(AioContext *ctx)
  64 {
  65 }
  66 #endif /* !CONFIG_EPOLL_CREATE1 */
  67
  68 #ifdef CONFIG_LINUX_IO_URING
  69 bool fdmon_io_uring_setup(AioContext *ctx);
  70 void fdmon_io_uring_destroy(AioContext *ctx);
  71 #else
  72 static inline bool fdmon_io_uring_setup(AioContext *ctx)
  73 {
  74     return false;
  75 }
  76
  77 static inline void fdmon_io_uring_destroy(AioContext *ctx)
  78 {
  79 }
  80 #endif /* !CONFIG_LINUX_IO_URING */
  81
  82 #endif /* AIO_POSIX_H */