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1 | 39b65c2e | aliguori | /*
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2 | 39b65c2e | aliguori | * QEMU buffered QEMUFile
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3 | 39b65c2e | aliguori | *
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4 | 39b65c2e | aliguori | * Copyright IBM, Corp. 2008
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5 | 39b65c2e | aliguori | *
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6 | 39b65c2e | aliguori | * Authors:
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7 | 39b65c2e | aliguori | * Anthony Liguori <aliguori@us.ibm.com>
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8 | 39b65c2e | aliguori | *
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9 | 39b65c2e | aliguori | * This work is licensed under the terms of the GNU GPL, version 2. See
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10 | 39b65c2e | aliguori | * the COPYING file in the top-level directory.
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11 | 39b65c2e | aliguori | *
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12 | 6b620ca3 | Paolo Bonzini | * Contributions after 2012-01-13 are licensed under the terms of the
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13 | 6b620ca3 | Paolo Bonzini | * GNU GPL, version 2 or (at your option) any later version.
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14 | 39b65c2e | aliguori | */
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15 | 39b65c2e | aliguori | |
16 | 39b65c2e | aliguori | #include "qemu-common.h" |
17 | 39b65c2e | aliguori | #include "hw/hw.h" |
18 | 39b65c2e | aliguori | #include "qemu-timer.h" |
19 | 39b65c2e | aliguori | #include "qemu-char.h" |
20 | 39b65c2e | aliguori | #include "buffered_file.h" |
21 | 39b65c2e | aliguori | |
22 | 39b65c2e | aliguori | //#define DEBUG_BUFFERED_FILE
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23 | 39b65c2e | aliguori | |
24 | 39b65c2e | aliguori | typedef struct QEMUFileBuffered |
25 | 39b65c2e | aliguori | { |
26 | 39b65c2e | aliguori | BufferedPutFunc *put_buffer; |
27 | 39b65c2e | aliguori | BufferedPutReadyFunc *put_ready; |
28 | 39b65c2e | aliguori | BufferedWaitForUnfreezeFunc *wait_for_unfreeze; |
29 | 39b65c2e | aliguori | BufferedCloseFunc *close; |
30 | 39b65c2e | aliguori | void *opaque;
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31 | 39b65c2e | aliguori | QEMUFile *file; |
32 | 39b65c2e | aliguori | int freeze_output;
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33 | 39b65c2e | aliguori | size_t bytes_xfer; |
34 | 39b65c2e | aliguori | size_t xfer_limit; |
35 | 39b65c2e | aliguori | uint8_t *buffer; |
36 | 39b65c2e | aliguori | size_t buffer_size; |
37 | 39b65c2e | aliguori | size_t buffer_capacity; |
38 | 39b65c2e | aliguori | QEMUTimer *timer; |
39 | 39b65c2e | aliguori | } QEMUFileBuffered; |
40 | 39b65c2e | aliguori | |
41 | 39b65c2e | aliguori | #ifdef DEBUG_BUFFERED_FILE
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42 | d0f2c4c6 | malc | #define DPRINTF(fmt, ...) \
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43 | 39b65c2e | aliguori | do { printf("buffered-file: " fmt, ## __VA_ARGS__); } while (0) |
44 | 39b65c2e | aliguori | #else
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45 | d0f2c4c6 | malc | #define DPRINTF(fmt, ...) \
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46 | 39b65c2e | aliguori | do { } while (0) |
47 | 39b65c2e | aliguori | #endif
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48 | 39b65c2e | aliguori | |
49 | 39b65c2e | aliguori | static void buffered_append(QEMUFileBuffered *s, |
50 | 39b65c2e | aliguori | const uint8_t *buf, size_t size)
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51 | 39b65c2e | aliguori | { |
52 | 39b65c2e | aliguori | if (size > (s->buffer_capacity - s->buffer_size)) {
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53 | 39b65c2e | aliguori | void *tmp;
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54 | 39b65c2e | aliguori | |
55 | d0f2c4c6 | malc | DPRINTF("increasing buffer capacity from %zu by %zu\n",
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56 | 39b65c2e | aliguori | s->buffer_capacity, size + 1024);
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57 | 39b65c2e | aliguori | |
58 | 39b65c2e | aliguori | s->buffer_capacity += size + 1024;
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59 | 39b65c2e | aliguori | |
60 | 7267c094 | Anthony Liguori | tmp = g_realloc(s->buffer, s->buffer_capacity); |
61 | 39b65c2e | aliguori | if (tmp == NULL) { |
62 | 39b65c2e | aliguori | fprintf(stderr, "qemu file buffer expansion failed\n");
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63 | 39b65c2e | aliguori | exit(1);
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64 | 39b65c2e | aliguori | } |
65 | 39b65c2e | aliguori | |
66 | 39b65c2e | aliguori | s->buffer = tmp; |
67 | 39b65c2e | aliguori | } |
68 | 39b65c2e | aliguori | |
69 | 39b65c2e | aliguori | memcpy(s->buffer + s->buffer_size, buf, size); |
70 | 39b65c2e | aliguori | s->buffer_size += size; |
71 | 39b65c2e | aliguori | } |
72 | 39b65c2e | aliguori | |
73 | 39b65c2e | aliguori | static void buffered_flush(QEMUFileBuffered *s) |
74 | 39b65c2e | aliguori | { |
75 | 39b65c2e | aliguori | size_t offset = 0;
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76 | 42802d47 | Juan Quintela | int error;
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77 | 39b65c2e | aliguori | |
78 | 42802d47 | Juan Quintela | error = qemu_file_get_error(s->file); |
79 | 42802d47 | Juan Quintela | if (error != 0) { |
80 | 42802d47 | Juan Quintela | DPRINTF("flush when error, bailing: %s\n", strerror(-error));
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81 | 39b65c2e | aliguori | return;
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82 | 39b65c2e | aliguori | } |
83 | 39b65c2e | aliguori | |
84 | d0f2c4c6 | malc | DPRINTF("flushing %zu byte(s) of data\n", s->buffer_size);
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85 | 39b65c2e | aliguori | |
86 | 39b65c2e | aliguori | while (offset < s->buffer_size) {
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87 | 39b65c2e | aliguori | ssize_t ret; |
88 | 39b65c2e | aliguori | |
89 | 39b65c2e | aliguori | ret = s->put_buffer(s->opaque, s->buffer + offset, |
90 | 39b65c2e | aliguori | s->buffer_size - offset); |
91 | 39b65c2e | aliguori | if (ret == -EAGAIN) {
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92 | d0f2c4c6 | malc | DPRINTF("backend not ready, freezing\n");
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93 | 39b65c2e | aliguori | s->freeze_output = 1;
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94 | 39b65c2e | aliguori | break;
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95 | 39b65c2e | aliguori | } |
96 | 39b65c2e | aliguori | |
97 | 39b65c2e | aliguori | if (ret <= 0) { |
98 | d0f2c4c6 | malc | DPRINTF("error flushing data, %zd\n", ret);
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99 | dcd1d224 | Juan Quintela | qemu_file_set_error(s->file, ret); |
100 | 39b65c2e | aliguori | break;
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101 | 39b65c2e | aliguori | } else {
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102 | d0f2c4c6 | malc | DPRINTF("flushed %zd byte(s)\n", ret);
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103 | 39b65c2e | aliguori | offset += ret; |
104 | 39b65c2e | aliguori | } |
105 | 39b65c2e | aliguori | } |
106 | 39b65c2e | aliguori | |
107 | d0f2c4c6 | malc | DPRINTF("flushed %zu of %zu byte(s)\n", offset, s->buffer_size);
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108 | 39b65c2e | aliguori | memmove(s->buffer, s->buffer + offset, s->buffer_size - offset); |
109 | 39b65c2e | aliguori | s->buffer_size -= offset; |
110 | 39b65c2e | aliguori | } |
111 | 39b65c2e | aliguori | |
112 | 39b65c2e | aliguori | static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size) |
113 | 39b65c2e | aliguori | { |
114 | 39b65c2e | aliguori | QEMUFileBuffered *s = opaque; |
115 | 42802d47 | Juan Quintela | int offset = 0, error; |
116 | 39b65c2e | aliguori | ssize_t ret; |
117 | 39b65c2e | aliguori | |
118 | d0f2c4c6 | malc | DPRINTF("putting %d bytes at %" PRId64 "\n", size, pos); |
119 | 39b65c2e | aliguori | |
120 | 42802d47 | Juan Quintela | error = qemu_file_get_error(s->file); |
121 | 42802d47 | Juan Quintela | if (error) {
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122 | 42802d47 | Juan Quintela | DPRINTF("flush when error, bailing: %s\n", strerror(-error));
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123 | 42802d47 | Juan Quintela | return error;
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124 | 39b65c2e | aliguori | } |
125 | 39b65c2e | aliguori | |
126 | d0f2c4c6 | malc | DPRINTF("unfreezing output\n");
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127 | 39b65c2e | aliguori | s->freeze_output = 0;
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128 | 39b65c2e | aliguori | |
129 | 39b65c2e | aliguori | buffered_flush(s); |
130 | 39b65c2e | aliguori | |
131 | 39b65c2e | aliguori | while (!s->freeze_output && offset < size) {
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132 | 39b65c2e | aliguori | if (s->bytes_xfer > s->xfer_limit) {
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133 | d0f2c4c6 | malc | DPRINTF("transfer limit exceeded when putting\n");
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134 | 39b65c2e | aliguori | break;
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135 | 39b65c2e | aliguori | } |
136 | 39b65c2e | aliguori | |
137 | 39b65c2e | aliguori | ret = s->put_buffer(s->opaque, buf + offset, size - offset); |
138 | 39b65c2e | aliguori | if (ret == -EAGAIN) {
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139 | d0f2c4c6 | malc | DPRINTF("backend not ready, freezing\n");
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140 | 39b65c2e | aliguori | s->freeze_output = 1;
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141 | 39b65c2e | aliguori | break;
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142 | 39b65c2e | aliguori | } |
143 | 39b65c2e | aliguori | |
144 | 39b65c2e | aliguori | if (ret <= 0) { |
145 | d0f2c4c6 | malc | DPRINTF("error putting\n");
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146 | dcd1d224 | Juan Quintela | qemu_file_set_error(s->file, ret); |
147 | 39b65c2e | aliguori | offset = -EINVAL; |
148 | 39b65c2e | aliguori | break;
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149 | 39b65c2e | aliguori | } |
150 | 39b65c2e | aliguori | |
151 | d0f2c4c6 | malc | DPRINTF("put %zd byte(s)\n", ret);
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152 | 39b65c2e | aliguori | offset += ret; |
153 | 39b65c2e | aliguori | s->bytes_xfer += ret; |
154 | 39b65c2e | aliguori | } |
155 | 39b65c2e | aliguori | |
156 | 39b65c2e | aliguori | if (offset >= 0) { |
157 | d0f2c4c6 | malc | DPRINTF("buffering %d bytes\n", size - offset);
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158 | 39b65c2e | aliguori | buffered_append(s, buf + offset, size - offset); |
159 | 39b65c2e | aliguori | offset = size; |
160 | 39b65c2e | aliguori | } |
161 | 39b65c2e | aliguori | |
162 | 5e77aaa0 | Avi Kivity | if (pos == 0 && size == 0) { |
163 | 5e77aaa0 | Avi Kivity | DPRINTF("file is ready\n");
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164 | 5e77aaa0 | Avi Kivity | if (s->bytes_xfer <= s->xfer_limit) {
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165 | 5e77aaa0 | Avi Kivity | DPRINTF("notifying client\n");
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166 | 5e77aaa0 | Avi Kivity | s->put_ready(s->opaque); |
167 | 5e77aaa0 | Avi Kivity | } |
168 | 5e77aaa0 | Avi Kivity | } |
169 | 5e77aaa0 | Avi Kivity | |
170 | 39b65c2e | aliguori | return offset;
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171 | 39b65c2e | aliguori | } |
172 | 39b65c2e | aliguori | |
173 | 39b65c2e | aliguori | static int buffered_close(void *opaque) |
174 | 39b65c2e | aliguori | { |
175 | 39b65c2e | aliguori | QEMUFileBuffered *s = opaque; |
176 | 39b65c2e | aliguori | int ret;
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177 | 39b65c2e | aliguori | |
178 | d0f2c4c6 | malc | DPRINTF("closing\n");
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179 | 39b65c2e | aliguori | |
180 | 624b9cc2 | Juan Quintela | while (!qemu_file_get_error(s->file) && s->buffer_size) {
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181 | 39b65c2e | aliguori | buffered_flush(s); |
182 | 39b65c2e | aliguori | if (s->freeze_output)
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183 | db448a08 | Juan Quintela | s->wait_for_unfreeze(s->opaque); |
184 | 39b65c2e | aliguori | } |
185 | 39b65c2e | aliguori | |
186 | 39b65c2e | aliguori | ret = s->close(s->opaque); |
187 | 39b65c2e | aliguori | |
188 | 39b65c2e | aliguori | qemu_del_timer(s->timer); |
189 | 39b65c2e | aliguori | qemu_free_timer(s->timer); |
190 | 7267c094 | Anthony Liguori | g_free(s->buffer); |
191 | 7267c094 | Anthony Liguori | g_free(s); |
192 | 39b65c2e | aliguori | |
193 | 39b65c2e | aliguori | return ret;
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194 | 39b65c2e | aliguori | } |
195 | 39b65c2e | aliguori | |
196 | 4fc7d819 | Juan Quintela | /*
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197 | 4fc7d819 | Juan Quintela | * The meaning of the return values is:
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198 | 4fc7d819 | Juan Quintela | * 0: We can continue sending
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199 | 4fc7d819 | Juan Quintela | * 1: Time to stop
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200 | 42802d47 | Juan Quintela | * negative: There has been an error
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201 | 4fc7d819 | Juan Quintela | */
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202 | 39b65c2e | aliguori | static int buffered_rate_limit(void *opaque) |
203 | 39b65c2e | aliguori | { |
204 | 39b65c2e | aliguori | QEMUFileBuffered *s = opaque; |
205 | 42802d47 | Juan Quintela | int ret;
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206 | 39b65c2e | aliguori | |
207 | 42802d47 | Juan Quintela | ret = qemu_file_get_error(s->file); |
208 | 42802d47 | Juan Quintela | if (ret) {
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209 | 42802d47 | Juan Quintela | return ret;
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210 | 4fc7d819 | Juan Quintela | } |
211 | 39b65c2e | aliguori | if (s->freeze_output)
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212 | 39b65c2e | aliguori | return 1; |
213 | 39b65c2e | aliguori | |
214 | 39b65c2e | aliguori | if (s->bytes_xfer > s->xfer_limit)
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215 | 39b65c2e | aliguori | return 1; |
216 | 39b65c2e | aliguori | |
217 | 39b65c2e | aliguori | return 0; |
218 | 39b65c2e | aliguori | } |
219 | 39b65c2e | aliguori | |
220 | 3d002df3 | Michael S. Tsirkin | static int64_t buffered_set_rate_limit(void *opaque, int64_t new_rate) |
221 | 19629537 | Glauber Costa | { |
222 | 19629537 | Glauber Costa | QEMUFileBuffered *s = opaque; |
223 | 624b9cc2 | Juan Quintela | if (qemu_file_get_error(s->file)) {
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224 | 19629537 | Glauber Costa | goto out;
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225 | 624b9cc2 | Juan Quintela | } |
226 | 3d002df3 | Michael S. Tsirkin | if (new_rate > SIZE_MAX) {
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227 | 3d002df3 | Michael S. Tsirkin | new_rate = SIZE_MAX; |
228 | 3d002df3 | Michael S. Tsirkin | } |
229 | 3d002df3 | Michael S. Tsirkin | |
230 | 19629537 | Glauber Costa | s->xfer_limit = new_rate / 10;
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231 | 19629537 | Glauber Costa | |
232 | 19629537 | Glauber Costa | out:
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233 | 19629537 | Glauber Costa | return s->xfer_limit;
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234 | 19629537 | Glauber Costa | } |
235 | 19629537 | Glauber Costa | |
236 | 3d002df3 | Michael S. Tsirkin | static int64_t buffered_get_rate_limit(void *opaque) |
237 | c163b5ca | lirans@il.ibm.com | { |
238 | c163b5ca | lirans@il.ibm.com | QEMUFileBuffered *s = opaque; |
239 | c163b5ca | lirans@il.ibm.com | |
240 | c163b5ca | lirans@il.ibm.com | return s->xfer_limit;
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241 | c163b5ca | lirans@il.ibm.com | } |
242 | c163b5ca | lirans@il.ibm.com | |
243 | 39b65c2e | aliguori | static void buffered_rate_tick(void *opaque) |
244 | 39b65c2e | aliguori | { |
245 | 39b65c2e | aliguori | QEMUFileBuffered *s = opaque; |
246 | 39b65c2e | aliguori | |
247 | 624b9cc2 | Juan Quintela | if (qemu_file_get_error(s->file)) {
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248 | e447b1a6 | Marcelo Tosatti | buffered_close(s); |
249 | 39b65c2e | aliguori | return;
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250 | e447b1a6 | Marcelo Tosatti | } |
251 | 39b65c2e | aliguori | |
252 | 7bd427d8 | Paolo Bonzini | qemu_mod_timer(s->timer, qemu_get_clock_ms(rt_clock) + 100);
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253 | 39b65c2e | aliguori | |
254 | 39b65c2e | aliguori | if (s->freeze_output)
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255 | 39b65c2e | aliguori | return;
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256 | 39b65c2e | aliguori | |
257 | 39b65c2e | aliguori | s->bytes_xfer = 0;
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258 | 39b65c2e | aliguori | |
259 | 39b65c2e | aliguori | buffered_flush(s); |
260 | 39b65c2e | aliguori | |
261 | 39b65c2e | aliguori | /* Add some checks around this */
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262 | 39b65c2e | aliguori | s->put_ready(s->opaque); |
263 | 39b65c2e | aliguori | } |
264 | 39b65c2e | aliguori | |
265 | 39b65c2e | aliguori | QEMUFile *qemu_fopen_ops_buffered(void *opaque,
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266 | 39b65c2e | aliguori | size_t bytes_per_sec, |
267 | 39b65c2e | aliguori | BufferedPutFunc *put_buffer, |
268 | 39b65c2e | aliguori | BufferedPutReadyFunc *put_ready, |
269 | 39b65c2e | aliguori | BufferedWaitForUnfreezeFunc *wait_for_unfreeze, |
270 | 39b65c2e | aliguori | BufferedCloseFunc *close) |
271 | 39b65c2e | aliguori | { |
272 | 39b65c2e | aliguori | QEMUFileBuffered *s; |
273 | 39b65c2e | aliguori | |
274 | 7267c094 | Anthony Liguori | s = g_malloc0(sizeof(*s));
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275 | 39b65c2e | aliguori | |
276 | 39b65c2e | aliguori | s->opaque = opaque; |
277 | 39b65c2e | aliguori | s->xfer_limit = bytes_per_sec / 10;
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278 | 39b65c2e | aliguori | s->put_buffer = put_buffer; |
279 | 39b65c2e | aliguori | s->put_ready = put_ready; |
280 | 39b65c2e | aliguori | s->wait_for_unfreeze = wait_for_unfreeze; |
281 | 39b65c2e | aliguori | s->close = close; |
282 | 39b65c2e | aliguori | |
283 | 39b65c2e | aliguori | s->file = qemu_fopen_ops(s, buffered_put_buffer, NULL,
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284 | 19629537 | Glauber Costa | buffered_close, buffered_rate_limit, |
285 | c163b5ca | lirans@il.ibm.com | buffered_set_rate_limit, |
286 | c163b5ca | lirans@il.ibm.com | buffered_get_rate_limit); |
287 | 39b65c2e | aliguori | |
288 | 7bd427d8 | Paolo Bonzini | s->timer = qemu_new_timer_ms(rt_clock, buffered_rate_tick, s); |
289 | 39b65c2e | aliguori | |
290 | 7bd427d8 | Paolo Bonzini | qemu_mod_timer(s->timer, qemu_get_clock_ms(rt_clock) + 100);
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291 | 39b65c2e | aliguori | |
292 | 39b65c2e | aliguori | return s->file;
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293 | 39b65c2e | aliguori | } |