1
2 /*
3 * Copyright (C) Igor Sysoev
4 * Copyright (C) Nginx, Inc.
5 */
6
7
8 #include <ngx_config.h>
9 #include <ngx_core.h>
10 #include <ngx_event.h>
11
12
13 extern int ngx_eventfd;
14 extern aio_context_t ngx_aio_ctx;
15
16
17 static void ngx_file_aio_event_handler(ngx_event_t *ev);
18
19
20 static int
io_submit(aio_context_t ctx,long n,struct iocb ** paiocb)21 io_submit(aio_context_t ctx, long n, struct iocb **paiocb)
22 {
23 return syscall(SYS_io_submit, ctx, n, paiocb);
24 }
25
26
27 ngx_int_t
ngx_file_aio_init(ngx_file_t * file,ngx_pool_t * pool)28 ngx_file_aio_init(ngx_file_t *file, ngx_pool_t *pool)
29 {
30 ngx_event_aio_t *aio;
31
32 aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t));
33 if (aio == NULL) {
34 return NGX_ERROR;
35 }
36
37 aio->file = file;
38 aio->fd = file->fd;
39 aio->event.data = aio;
40 aio->event.ready = 1;
41 aio->event.log = file->log;
42
43 file->aio = aio;
44
45 return NGX_OK;
46 }
47
48
49 ssize_t
ngx_file_aio_read(ngx_file_t * file,u_char * buf,size_t size,off_t offset,ngx_pool_t * pool)50 ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset,
51 ngx_pool_t *pool)
52 {
53 ngx_err_t err;
54 struct iocb *piocb[1];
55 ngx_event_t *ev;
56 ngx_event_aio_t *aio;
57
58 if (!ngx_file_aio) {
59 return ngx_read_file(file, buf, size, offset);
60 }
61
62 if (file->aio == NULL && ngx_file_aio_init(file, pool) != NGX_OK) {
63 return NGX_ERROR;
64 }
65
66 aio = file->aio;
67 ev = &aio->event;
68
69 if (!ev->ready) {
70 ngx_log_error(NGX_LOG_ALERT, file->log, 0,
71 "second aio post for \"%V\"", &file->name);
72 return NGX_AGAIN;
73 }
74
75 ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0,
76 "aio complete:%d @%O:%uz %V",
77 ev->complete, offset, size, &file->name);
78
79 if (ev->complete) {
80 ev->active = 0;
81 ev->complete = 0;
82
83 if (aio->res >= 0) {
84 ngx_set_errno(0);
85 return aio->res;
86 }
87
88 ngx_set_errno(-aio->res);
89
90 ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno,
91 "aio read \"%s\" failed", file->name.data);
92
93 return NGX_ERROR;
94 }
95
96 ngx_memzero(&aio->aiocb, sizeof(struct iocb));
97
98 aio->aiocb.aio_data = (uint64_t) (uintptr_t) ev;
99 aio->aiocb.aio_lio_opcode = IOCB_CMD_PREAD;
100 aio->aiocb.aio_fildes = file->fd;
101 aio->aiocb.aio_buf = (uint64_t) (uintptr_t) buf;
102 aio->aiocb.aio_nbytes = size;
103 aio->aiocb.aio_offset = offset;
104 aio->aiocb.aio_flags = IOCB_FLAG_RESFD;
105 aio->aiocb.aio_resfd = ngx_eventfd;
106
107 ev->handler = ngx_file_aio_event_handler;
108
109 piocb[0] = &aio->aiocb;
110
111 if (io_submit(ngx_aio_ctx, 1, piocb) == 1) {
112 ev->active = 1;
113 ev->ready = 0;
114 ev->complete = 0;
115
116 return NGX_AGAIN;
117 }
118
119 err = ngx_errno;
120
121 if (err == NGX_EAGAIN) {
122 return ngx_read_file(file, buf, size, offset);
123 }
124
125 ngx_log_error(NGX_LOG_CRIT, file->log, err,
126 "io_submit(\"%V\") failed", &file->name);
127
128 if (err == NGX_ENOSYS) {
129 ngx_file_aio = 0;
130 return ngx_read_file(file, buf, size, offset);
131 }
132
133 return NGX_ERROR;
134 }
135
136
137 static void
ngx_file_aio_event_handler(ngx_event_t * ev)138 ngx_file_aio_event_handler(ngx_event_t *ev)
139 {
140 ngx_event_aio_t *aio;
141
142 aio = ev->data;
143
144 ngx_log_debug2(NGX_LOG_DEBUG_CORE, ev->log, 0,
145 "aio event handler fd:%d %V", aio->fd, &aio->file->name);
146
147 aio->handler(ev);
148 }
149