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1 | 3c529d93 | aliguori | /*
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2 | 3c529d93 | aliguori | * QEMU posix-aio emulation
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3 | 3c529d93 | aliguori | *
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4 | 3c529d93 | aliguori | * Copyright IBM, Corp. 2008
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5 | 3c529d93 | aliguori | *
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6 | 3c529d93 | aliguori | * Authors:
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7 | 3c529d93 | aliguori | * Anthony Liguori <aliguori@us.ibm.com>
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8 | 3c529d93 | aliguori | *
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9 | 3c529d93 | aliguori | * This work is licensed under the terms of the GNU GPL, version 2. See
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10 | 3c529d93 | aliguori | * the COPYING file in the top-level directory.
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11 | 3c529d93 | aliguori | *
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12 | 3c529d93 | aliguori | */
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13 | 3c529d93 | aliguori | |
14 | 3c529d93 | aliguori | #include <pthread.h> |
15 | 3c529d93 | aliguori | #include <unistd.h> |
16 | 3c529d93 | aliguori | #include <errno.h> |
17 | 3c529d93 | aliguori | #include <sys/time.h> |
18 | 3c529d93 | aliguori | #include "osdep.h" |
19 | 3c529d93 | aliguori | |
20 | 3c529d93 | aliguori | #include "posix-aio-compat.h" |
21 | 3c529d93 | aliguori | |
22 | 3c529d93 | aliguori | static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
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23 | 3c529d93 | aliguori | static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
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24 | 3c529d93 | aliguori | static pthread_t thread_id;
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25 | 3c529d93 | aliguori | static int max_threads = 64; |
26 | 3c529d93 | aliguori | static int cur_threads = 0; |
27 | 3c529d93 | aliguori | static int idle_threads = 0; |
28 | 3c529d93 | aliguori | static TAILQ_HEAD(, qemu_paiocb) request_list;
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29 | 3c529d93 | aliguori | |
30 | 3c529d93 | aliguori | static void *aio_thread(void *unused) |
31 | 3c529d93 | aliguori | { |
32 | 3c529d93 | aliguori | sigset_t set; |
33 | 3c529d93 | aliguori | |
34 | 3c529d93 | aliguori | /* block all signals */
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35 | 3c529d93 | aliguori | sigfillset(&set); |
36 | 3c529d93 | aliguori | sigprocmask(SIG_BLOCK, &set, NULL);
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37 | 3c529d93 | aliguori | |
38 | 3c529d93 | aliguori | while (1) { |
39 | 3c529d93 | aliguori | struct qemu_paiocb *aiocb;
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40 | 3c529d93 | aliguori | size_t offset; |
41 | 3c529d93 | aliguori | int ret = 0; |
42 | 3c529d93 | aliguori | |
43 | 3c529d93 | aliguori | pthread_mutex_lock(&lock); |
44 | 3c529d93 | aliguori | |
45 | 3c529d93 | aliguori | while (TAILQ_EMPTY(&request_list) &&
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46 | 3c529d93 | aliguori | !(ret == ETIMEDOUT)) { |
47 | 3c529d93 | aliguori | struct timespec ts = { 0 }; |
48 | 3c529d93 | aliguori | qemu_timeval tv; |
49 | 3c529d93 | aliguori | |
50 | 3c529d93 | aliguori | qemu_gettimeofday(&tv); |
51 | 3c529d93 | aliguori | ts.tv_sec = tv.tv_sec + 10;
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52 | 3c529d93 | aliguori | ret = pthread_cond_timedwait(&cond, &lock, &ts); |
53 | 3c529d93 | aliguori | } |
54 | 3c529d93 | aliguori | |
55 | 3c529d93 | aliguori | if (ret == ETIMEDOUT)
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56 | 3c529d93 | aliguori | break;
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57 | 3c529d93 | aliguori | |
58 | 3c529d93 | aliguori | aiocb = TAILQ_FIRST(&request_list); |
59 | 3c529d93 | aliguori | TAILQ_REMOVE(&request_list, aiocb, node); |
60 | 3c529d93 | aliguori | |
61 | 3c529d93 | aliguori | offset = 0;
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62 | 3c529d93 | aliguori | aiocb->active = 1;
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63 | 3c529d93 | aliguori | |
64 | 3c529d93 | aliguori | idle_threads--; |
65 | 3c529d93 | aliguori | pthread_mutex_unlock(&lock); |
66 | 3c529d93 | aliguori | |
67 | 3c529d93 | aliguori | while (offset < aiocb->aio_nbytes) {
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68 | 3c529d93 | aliguori | ssize_t len; |
69 | 3c529d93 | aliguori | |
70 | 3c529d93 | aliguori | if (aiocb->is_write)
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71 | 3c529d93 | aliguori | len = pwrite(aiocb->aio_fildes, |
72 | 3c529d93 | aliguori | (const char *)aiocb->aio_buf + offset, |
73 | 3c529d93 | aliguori | aiocb->aio_nbytes - offset, |
74 | 3c529d93 | aliguori | aiocb->aio_offset + offset); |
75 | 3c529d93 | aliguori | else
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76 | 3c529d93 | aliguori | len = pread(aiocb->aio_fildes, |
77 | 3c529d93 | aliguori | (char *)aiocb->aio_buf + offset,
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78 | 3c529d93 | aliguori | aiocb->aio_nbytes - offset, |
79 | 3c529d93 | aliguori | aiocb->aio_offset + offset); |
80 | 3c529d93 | aliguori | |
81 | 3c529d93 | aliguori | if (len == -1 && errno == EINTR) |
82 | 3c529d93 | aliguori | continue;
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83 | 3c529d93 | aliguori | else if (len == -1) { |
84 | f094a782 | aliguori | offset = -errno; |
85 | 3c529d93 | aliguori | break;
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86 | 3c529d93 | aliguori | } else if (len == 0) |
87 | 3c529d93 | aliguori | break;
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88 | 3c529d93 | aliguori | |
89 | 3c529d93 | aliguori | offset += len; |
90 | 3c529d93 | aliguori | } |
91 | 3c529d93 | aliguori | |
92 | 3c529d93 | aliguori | pthread_mutex_lock(&lock); |
93 | f094a782 | aliguori | aiocb->ret = offset; |
94 | 3c529d93 | aliguori | idle_threads++; |
95 | 3c529d93 | aliguori | pthread_mutex_unlock(&lock); |
96 | 3c529d93 | aliguori | |
97 | 3c529d93 | aliguori | sigqueue(getpid(), |
98 | 3c529d93 | aliguori | aiocb->aio_sigevent.sigev_signo, |
99 | 3c529d93 | aliguori | aiocb->aio_sigevent.sigev_value); |
100 | 3c529d93 | aliguori | } |
101 | 3c529d93 | aliguori | |
102 | 3c529d93 | aliguori | idle_threads--; |
103 | 3c529d93 | aliguori | cur_threads--; |
104 | 3c529d93 | aliguori | pthread_mutex_unlock(&lock); |
105 | 3c529d93 | aliguori | |
106 | 3c529d93 | aliguori | return NULL; |
107 | 3c529d93 | aliguori | } |
108 | 3c529d93 | aliguori | |
109 | 3c529d93 | aliguori | static int spawn_thread(void) |
110 | 3c529d93 | aliguori | { |
111 | 3c529d93 | aliguori | pthread_attr_t attr; |
112 | 3c529d93 | aliguori | int ret;
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113 | 3c529d93 | aliguori | |
114 | 3c529d93 | aliguori | cur_threads++; |
115 | 3c529d93 | aliguori | idle_threads++; |
116 | 3c529d93 | aliguori | |
117 | 3c529d93 | aliguori | pthread_attr_init(&attr); |
118 | 3c529d93 | aliguori | pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); |
119 | 3c529d93 | aliguori | ret = pthread_create(&thread_id, &attr, aio_thread, NULL);
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120 | 3c529d93 | aliguori | pthread_attr_destroy(&attr); |
121 | 3c529d93 | aliguori | |
122 | 3c529d93 | aliguori | return ret;
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123 | 3c529d93 | aliguori | } |
124 | 3c529d93 | aliguori | |
125 | 3c529d93 | aliguori | int qemu_paio_init(struct qemu_paioinit *aioinit) |
126 | 3c529d93 | aliguori | { |
127 | 3c529d93 | aliguori | TAILQ_INIT(&request_list); |
128 | 3c529d93 | aliguori | |
129 | 3c529d93 | aliguori | return 0; |
130 | 3c529d93 | aliguori | } |
131 | 3c529d93 | aliguori | |
132 | 3c529d93 | aliguori | static int qemu_paio_submit(struct qemu_paiocb *aiocb, int is_write) |
133 | 3c529d93 | aliguori | { |
134 | 3c529d93 | aliguori | aiocb->is_write = is_write; |
135 | 3c529d93 | aliguori | aiocb->ret = -EINPROGRESS; |
136 | 3c529d93 | aliguori | aiocb->active = 0;
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137 | 3c529d93 | aliguori | pthread_mutex_lock(&lock); |
138 | 3c529d93 | aliguori | if (idle_threads == 0 && cur_threads < max_threads) |
139 | 3c529d93 | aliguori | spawn_thread(); |
140 | 3c529d93 | aliguori | TAILQ_INSERT_TAIL(&request_list, aiocb, node); |
141 | 3c529d93 | aliguori | pthread_mutex_unlock(&lock); |
142 | 3c529d93 | aliguori | pthread_cond_broadcast(&cond); |
143 | 3c529d93 | aliguori | |
144 | 3c529d93 | aliguori | return 0; |
145 | 3c529d93 | aliguori | } |
146 | 3c529d93 | aliguori | |
147 | 3c529d93 | aliguori | int qemu_paio_read(struct qemu_paiocb *aiocb) |
148 | 3c529d93 | aliguori | { |
149 | 3c529d93 | aliguori | return qemu_paio_submit(aiocb, 0); |
150 | 3c529d93 | aliguori | } |
151 | 3c529d93 | aliguori | |
152 | 3c529d93 | aliguori | int qemu_paio_write(struct qemu_paiocb *aiocb) |
153 | 3c529d93 | aliguori | { |
154 | 3c529d93 | aliguori | return qemu_paio_submit(aiocb, 1); |
155 | 3c529d93 | aliguori | } |
156 | 3c529d93 | aliguori | |
157 | 3c529d93 | aliguori | ssize_t qemu_paio_return(struct qemu_paiocb *aiocb)
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158 | 3c529d93 | aliguori | { |
159 | 3c529d93 | aliguori | ssize_t ret; |
160 | 3c529d93 | aliguori | |
161 | 3c529d93 | aliguori | pthread_mutex_lock(&lock); |
162 | 3c529d93 | aliguori | ret = aiocb->ret; |
163 | 3c529d93 | aliguori | pthread_mutex_unlock(&lock); |
164 | 3c529d93 | aliguori | |
165 | 3c529d93 | aliguori | return ret;
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166 | 3c529d93 | aliguori | } |
167 | 3c529d93 | aliguori | |
168 | 3c529d93 | aliguori | int qemu_paio_error(struct qemu_paiocb *aiocb) |
169 | 3c529d93 | aliguori | { |
170 | 3c529d93 | aliguori | ssize_t ret = qemu_paio_return(aiocb); |
171 | 3c529d93 | aliguori | |
172 | 3c529d93 | aliguori | if (ret < 0) |
173 | 3c529d93 | aliguori | ret = -ret; |
174 | 3c529d93 | aliguori | else
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175 | 3c529d93 | aliguori | ret = 0;
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176 | 3c529d93 | aliguori | |
177 | 3c529d93 | aliguori | return ret;
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178 | 3c529d93 | aliguori | } |
179 | 3c529d93 | aliguori | |
180 | 3c529d93 | aliguori | int qemu_paio_cancel(int fd, struct qemu_paiocb *aiocb) |
181 | 3c529d93 | aliguori | { |
182 | 3c529d93 | aliguori | int ret;
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183 | 3c529d93 | aliguori | |
184 | 3c529d93 | aliguori | pthread_mutex_lock(&lock); |
185 | 3c529d93 | aliguori | if (!aiocb->active) {
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186 | 3c529d93 | aliguori | TAILQ_REMOVE(&request_list, aiocb, node); |
187 | 3c529d93 | aliguori | aiocb->ret = -ECANCELED; |
188 | 3c529d93 | aliguori | ret = QEMU_PAIO_CANCELED; |
189 | 3c529d93 | aliguori | } else if (aiocb->ret == -EINPROGRESS) |
190 | 3c529d93 | aliguori | ret = QEMU_PAIO_NOTCANCELED; |
191 | 3c529d93 | aliguori | else
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192 | 3c529d93 | aliguori | ret = QEMU_PAIO_ALLDONE; |
193 | 3c529d93 | aliguori | pthread_mutex_unlock(&lock); |
194 | 3c529d93 | aliguori | |
195 | 3c529d93 | aliguori | return ret;
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196 | 3c529d93 | aliguori | } |