xref: /openbmc/qemu/util/aio-posix.h (revision c8c89a6a)
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 is_external;
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 */
83