xref: /openbmc/qemu/util/aio-posix.h (revision d2623129)
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_begin;
28     IOHandler *io_poll_end;
29     void *opaque;
30     QLIST_ENTRY(AioHandler) node;
31     QLIST_ENTRY(AioHandler) node_ready; /* only used during aio_poll() */
32     QLIST_ENTRY(AioHandler) node_deleted;
33     QLIST_ENTRY(AioHandler) node_poll;
34 #ifdef CONFIG_LINUX_IO_URING
35     QSLIST_ENTRY(AioHandler) node_submitted;
36     unsigned flags; /* see fdmon-io_uring.c */
37 #endif
38     int64_t poll_idle_timeout; /* when to stop userspace polling */
39     bool is_external;
40 };
41 
42 /* Add a handler to a ready list */
43 void aio_add_ready_handler(AioHandlerList *ready_list, AioHandler *node,
44                            int revents);
45 
46 extern const FDMonOps fdmon_poll_ops;
47 
48 #ifdef CONFIG_EPOLL_CREATE1
49 bool fdmon_epoll_try_upgrade(AioContext *ctx, unsigned npfd);
50 void fdmon_epoll_setup(AioContext *ctx);
51 void fdmon_epoll_disable(AioContext *ctx);
52 #else
53 static inline bool fdmon_epoll_try_upgrade(AioContext *ctx, unsigned npfd)
54 {
55     return false;
56 }
57 
58 static inline void fdmon_epoll_setup(AioContext *ctx)
59 {
60 }
61 
62 static inline void fdmon_epoll_disable(AioContext *ctx)
63 {
64 }
65 #endif /* !CONFIG_EPOLL_CREATE1 */
66 
67 #ifdef CONFIG_LINUX_IO_URING
68 bool fdmon_io_uring_setup(AioContext *ctx);
69 void fdmon_io_uring_destroy(AioContext *ctx);
70 #else
71 static inline bool fdmon_io_uring_setup(AioContext *ctx)
72 {
73     return false;
74 }
75 
76 static inline void fdmon_io_uring_destroy(AioContext *ctx)
77 {
78 }
79 #endif /* !CONFIG_LINUX_IO_URING */
80 
81 #endif /* AIO_POSIX_H */
82