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     bool is_external;
  42 };
  43
  44 /* Add a handler to a ready list */
  45 void aio_add_ready_handler(AioHandlerList *ready_list, AioHandler *node,
  46                            int revents);
  47
  48 extern const FDMonOps fdmon_poll_ops;
  49
  50 #ifdef CONFIG_EPOLL_CREATE1
  51 bool fdmon_epoll_try_upgrade(AioContext *ctx, unsigned npfd);
  52 void fdmon_epoll_setup(AioContext *ctx);
  53 void fdmon_epoll_disable(AioContext *ctx);
  54 #else
  55 static inline bool fdmon_epoll_try_upgrade(AioContext *ctx, unsigned npfd)
  56 {
  57     return false;
  58 }
  59
  60 static inline void fdmon_epoll_setup(AioContext *ctx)
  61 {
  62 }
  63
  64 static inline void fdmon_epoll_disable(AioContext *ctx)
  65 {
  66 }
  67 #endif /* !CONFIG_EPOLL_CREATE1 */
  68
  69 #ifdef CONFIG_LINUX_IO_URING
  70 bool fdmon_io_uring_setup(AioContext *ctx);
  71 void fdmon_io_uring_destroy(AioContext *ctx);
  72 #else
  73 static inline bool fdmon_io_uring_setup(AioContext *ctx)
  74 {
  75     return false;
  76 }
  77
  78 static inline void fdmon_io_uring_destroy(AioContext *ctx)
  79 {
  80 }
  81 #endif /* !CONFIG_LINUX_IO_URING */
  82
  83 #endif /* AIO_POSIX_H */