xref: /openbmc/qemu/util/aio-posix.h (revision d525f73f)
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 */
84