root / hw / xen_backend.c @ a8a358bf
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1 | d94f9486 | aliguori | /*
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2 | d94f9486 | aliguori | * xen backend driver infrastructure
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3 | d94f9486 | aliguori | * (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
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4 | d94f9486 | aliguori | *
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5 | d94f9486 | aliguori | * This program is free software; you can redistribute it and/or modify
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6 | d94f9486 | aliguori | * it under the terms of the GNU General Public License as published by
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7 | d94f9486 | aliguori | * the Free Software Foundation; under version 2 of the License.
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8 | d94f9486 | aliguori | *
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9 | d94f9486 | aliguori | * This program is distributed in the hope that it will be useful,
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10 | d94f9486 | aliguori | * but WITHOUT ANY WARRANTY; without even the implied warranty of
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11 | d94f9486 | aliguori | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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12 | d94f9486 | aliguori | * GNU General Public License for more details.
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13 | d94f9486 | aliguori | *
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14 | d94f9486 | aliguori | * You should have received a copy of the GNU General Public License along
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15 | 8167ee88 | Blue Swirl | * with this program; if not, see <http://www.gnu.org/licenses/>.
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16 | d94f9486 | aliguori | */
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17 | d94f9486 | aliguori | |
18 | d94f9486 | aliguori | /*
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19 | d94f9486 | aliguori | * TODO: add some xenbus / xenstore concepts overview here.
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20 | d94f9486 | aliguori | */
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21 | d94f9486 | aliguori | |
22 | d94f9486 | aliguori | #include <stdio.h> |
23 | d94f9486 | aliguori | #include <stdlib.h> |
24 | d94f9486 | aliguori | #include <stdarg.h> |
25 | d94f9486 | aliguori | #include <string.h> |
26 | d94f9486 | aliguori | #include <unistd.h> |
27 | d94f9486 | aliguori | #include <fcntl.h> |
28 | d94f9486 | aliguori | #include <inttypes.h> |
29 | d94f9486 | aliguori | #include <sys/types.h> |
30 | d94f9486 | aliguori | #include <sys/stat.h> |
31 | d94f9486 | aliguori | #include <sys/mman.h> |
32 | d94f9486 | aliguori | #include <sys/signal.h> |
33 | d94f9486 | aliguori | |
34 | d94f9486 | aliguori | #include <xs.h> |
35 | d94f9486 | aliguori | #include <xenctrl.h> |
36 | d94f9486 | aliguori | #include <xen/grant_table.h> |
37 | d94f9486 | aliguori | |
38 | d94f9486 | aliguori | #include "hw.h" |
39 | d94f9486 | aliguori | #include "qemu-char.h" |
40 | 2567f579 | Blue Swirl | #include "qemu-log.h" |
41 | d94f9486 | aliguori | #include "xen_backend.h" |
42 | d94f9486 | aliguori | |
43 | d94f9486 | aliguori | /* ------------------------------------------------------------- */
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44 | d94f9486 | aliguori | |
45 | d94f9486 | aliguori | /* public */
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46 | d94f9486 | aliguori | int xen_xc;
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47 | d94f9486 | aliguori | struct xs_handle *xenstore = NULL; |
48 | 2c8b24a3 | aliguori | const char *xen_protocol; |
49 | d94f9486 | aliguori | |
50 | d94f9486 | aliguori | /* private */
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51 | d94f9486 | aliguori | static TAILQ_HEAD(XenDeviceHead, XenDevice) xendevs = TAILQ_HEAD_INITIALIZER(xendevs);
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52 | d94f9486 | aliguori | static int debug = 0; |
53 | d94f9486 | aliguori | |
54 | d94f9486 | aliguori | /* ------------------------------------------------------------- */
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55 | d94f9486 | aliguori | |
56 | d94f9486 | aliguori | int xenstore_write_str(const char *base, const char *node, const char *val) |
57 | d94f9486 | aliguori | { |
58 | d94f9486 | aliguori | char abspath[XEN_BUFSIZE];
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59 | d94f9486 | aliguori | |
60 | d94f9486 | aliguori | snprintf(abspath, sizeof(abspath), "%s/%s", base, node); |
61 | d94f9486 | aliguori | if (!xs_write(xenstore, 0, abspath, val, strlen(val))) |
62 | d94f9486 | aliguori | return -1; |
63 | d94f9486 | aliguori | return 0; |
64 | d94f9486 | aliguori | } |
65 | d94f9486 | aliguori | |
66 | d94f9486 | aliguori | char *xenstore_read_str(const char *base, const char *node) |
67 | d94f9486 | aliguori | { |
68 | d94f9486 | aliguori | char abspath[XEN_BUFSIZE];
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69 | d94f9486 | aliguori | unsigned int len; |
70 | d94f9486 | aliguori | char *str, *ret = NULL; |
71 | d94f9486 | aliguori | |
72 | d94f9486 | aliguori | snprintf(abspath, sizeof(abspath), "%s/%s", base, node); |
73 | d94f9486 | aliguori | str = xs_read(xenstore, 0, abspath, &len);
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74 | d94f9486 | aliguori | if (str != NULL) { |
75 | d94f9486 | aliguori | /* move to qemu-allocated memory to make sure
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76 | d94f9486 | aliguori | * callers can savely qemu_free() stuff. */
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77 | d94f9486 | aliguori | ret = qemu_strdup(str); |
78 | d94f9486 | aliguori | free(str); |
79 | d94f9486 | aliguori | } |
80 | d94f9486 | aliguori | return ret;
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81 | d94f9486 | aliguori | } |
82 | d94f9486 | aliguori | |
83 | d94f9486 | aliguori | int xenstore_write_int(const char *base, const char *node, int ival) |
84 | d94f9486 | aliguori | { |
85 | d94f9486 | aliguori | char val[32]; |
86 | d94f9486 | aliguori | |
87 | d94f9486 | aliguori | snprintf(val, sizeof(val), "%d", ival); |
88 | d94f9486 | aliguori | return xenstore_write_str(base, node, val);
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89 | d94f9486 | aliguori | } |
90 | d94f9486 | aliguori | |
91 | d94f9486 | aliguori | int xenstore_read_int(const char *base, const char *node, int *ival) |
92 | d94f9486 | aliguori | { |
93 | d94f9486 | aliguori | char *val;
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94 | d94f9486 | aliguori | int rc = -1; |
95 | d94f9486 | aliguori | |
96 | d94f9486 | aliguori | val = xenstore_read_str(base, node); |
97 | d94f9486 | aliguori | if (val && 1 == sscanf(val, "%d", ival)) |
98 | d94f9486 | aliguori | rc = 0;
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99 | d94f9486 | aliguori | qemu_free(val); |
100 | d94f9486 | aliguori | return rc;
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101 | d94f9486 | aliguori | } |
102 | d94f9486 | aliguori | |
103 | d94f9486 | aliguori | int xenstore_write_be_str(struct XenDevice *xendev, const char *node, const char *val) |
104 | d94f9486 | aliguori | { |
105 | d94f9486 | aliguori | return xenstore_write_str(xendev->be, node, val);
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106 | d94f9486 | aliguori | } |
107 | d94f9486 | aliguori | |
108 | d94f9486 | aliguori | int xenstore_write_be_int(struct XenDevice *xendev, const char *node, int ival) |
109 | d94f9486 | aliguori | { |
110 | d94f9486 | aliguori | return xenstore_write_int(xendev->be, node, ival);
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111 | d94f9486 | aliguori | } |
112 | d94f9486 | aliguori | |
113 | d94f9486 | aliguori | char *xenstore_read_be_str(struct XenDevice *xendev, const char *node) |
114 | d94f9486 | aliguori | { |
115 | d94f9486 | aliguori | return xenstore_read_str(xendev->be, node);
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116 | d94f9486 | aliguori | } |
117 | d94f9486 | aliguori | |
118 | d94f9486 | aliguori | int xenstore_read_be_int(struct XenDevice *xendev, const char *node, int *ival) |
119 | d94f9486 | aliguori | { |
120 | d94f9486 | aliguori | return xenstore_read_int(xendev->be, node, ival);
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121 | d94f9486 | aliguori | } |
122 | d94f9486 | aliguori | |
123 | d94f9486 | aliguori | char *xenstore_read_fe_str(struct XenDevice *xendev, const char *node) |
124 | d94f9486 | aliguori | { |
125 | d94f9486 | aliguori | return xenstore_read_str(xendev->fe, node);
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126 | d94f9486 | aliguori | } |
127 | d94f9486 | aliguori | |
128 | d94f9486 | aliguori | int xenstore_read_fe_int(struct XenDevice *xendev, const char *node, int *ival) |
129 | d94f9486 | aliguori | { |
130 | d94f9486 | aliguori | return xenstore_read_int(xendev->fe, node, ival);
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131 | d94f9486 | aliguori | } |
132 | d94f9486 | aliguori | |
133 | d94f9486 | aliguori | /* ------------------------------------------------------------- */
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134 | d94f9486 | aliguori | |
135 | d94f9486 | aliguori | const char *xenbus_strstate(enum xenbus_state state) |
136 | d94f9486 | aliguori | { |
137 | d94f9486 | aliguori | static const char *const name[] = { |
138 | d94f9486 | aliguori | [ XenbusStateUnknown ] = "Unknown",
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139 | d94f9486 | aliguori | [ XenbusStateInitialising ] = "Initialising",
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140 | d94f9486 | aliguori | [ XenbusStateInitWait ] = "InitWait",
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141 | d94f9486 | aliguori | [ XenbusStateInitialised ] = "Initialised",
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142 | d94f9486 | aliguori | [ XenbusStateConnected ] = "Connected",
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143 | d94f9486 | aliguori | [ XenbusStateClosing ] = "Closing",
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144 | d94f9486 | aliguori | [ XenbusStateClosed ] = "Closed",
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145 | d94f9486 | aliguori | }; |
146 | d94f9486 | aliguori | return (state < ARRAY_SIZE(name)) ? name[state] : "INVALID"; |
147 | d94f9486 | aliguori | } |
148 | d94f9486 | aliguori | |
149 | d94f9486 | aliguori | int xen_be_set_state(struct XenDevice *xendev, enum xenbus_state state) |
150 | d94f9486 | aliguori | { |
151 | d94f9486 | aliguori | int rc;
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152 | d94f9486 | aliguori | |
153 | d94f9486 | aliguori | rc = xenstore_write_be_int(xendev, "state", state);
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154 | d94f9486 | aliguori | if (rc < 0) |
155 | d94f9486 | aliguori | return rc;
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156 | d94f9486 | aliguori | xen_be_printf(xendev, 1, "backend state: %s -> %s\n", |
157 | d94f9486 | aliguori | xenbus_strstate(xendev->be_state), xenbus_strstate(state)); |
158 | d94f9486 | aliguori | xendev->be_state = state; |
159 | d94f9486 | aliguori | return 0; |
160 | d94f9486 | aliguori | } |
161 | d94f9486 | aliguori | |
162 | d94f9486 | aliguori | /* ------------------------------------------------------------- */
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163 | d94f9486 | aliguori | |
164 | d94f9486 | aliguori | struct XenDevice *xen_be_find_xendev(const char *type, int dom, int dev) |
165 | d94f9486 | aliguori | { |
166 | d94f9486 | aliguori | struct XenDevice *xendev;
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167 | d94f9486 | aliguori | |
168 | d94f9486 | aliguori | TAILQ_FOREACH(xendev, &xendevs, next) { |
169 | d94f9486 | aliguori | if (xendev->dom != dom)
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170 | d94f9486 | aliguori | continue;
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171 | d94f9486 | aliguori | if (xendev->dev != dev)
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172 | d94f9486 | aliguori | continue;
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173 | d94f9486 | aliguori | if (strcmp(xendev->type, type) != 0) |
174 | d94f9486 | aliguori | continue;
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175 | d94f9486 | aliguori | return xendev;
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176 | d94f9486 | aliguori | } |
177 | d94f9486 | aliguori | return NULL; |
178 | d94f9486 | aliguori | } |
179 | d94f9486 | aliguori | |
180 | d94f9486 | aliguori | /*
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181 | d94f9486 | aliguori | * get xen backend device, allocate a new one if it doesn't exist.
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182 | d94f9486 | aliguori | */
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183 | d94f9486 | aliguori | static struct XenDevice *xen_be_get_xendev(const char *type, int dom, int dev, |
184 | d94f9486 | aliguori | struct XenDevOps *ops)
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185 | d94f9486 | aliguori | { |
186 | d94f9486 | aliguori | struct XenDevice *xendev;
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187 | d94f9486 | aliguori | char *dom0;
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188 | d94f9486 | aliguori | |
189 | d94f9486 | aliguori | xendev = xen_be_find_xendev(type, dom, dev); |
190 | d94f9486 | aliguori | if (xendev)
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191 | d94f9486 | aliguori | return xendev;
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192 | d94f9486 | aliguori | |
193 | d94f9486 | aliguori | /* init new xendev */
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194 | d94f9486 | aliguori | xendev = qemu_mallocz(ops->size); |
195 | d94f9486 | aliguori | xendev->type = type; |
196 | d94f9486 | aliguori | xendev->dom = dom; |
197 | d94f9486 | aliguori | xendev->dev = dev; |
198 | d94f9486 | aliguori | xendev->ops = ops; |
199 | d94f9486 | aliguori | |
200 | d94f9486 | aliguori | dom0 = xs_get_domain_path(xenstore, 0);
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201 | d94f9486 | aliguori | snprintf(xendev->be, sizeof(xendev->be), "%s/backend/%s/%d/%d", |
202 | d94f9486 | aliguori | dom0, xendev->type, xendev->dom, xendev->dev); |
203 | d94f9486 | aliguori | snprintf(xendev->name, sizeof(xendev->name), "%s-%d", |
204 | d94f9486 | aliguori | xendev->type, xendev->dev); |
205 | d94f9486 | aliguori | free(dom0); |
206 | d94f9486 | aliguori | |
207 | d94f9486 | aliguori | xendev->debug = debug; |
208 | d94f9486 | aliguori | xendev->local_port = -1;
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209 | d94f9486 | aliguori | |
210 | d94f9486 | aliguori | xendev->evtchndev = xc_evtchn_open(); |
211 | d94f9486 | aliguori | if (xendev->evtchndev < 0) { |
212 | d94f9486 | aliguori | xen_be_printf(NULL, 0, "can't open evtchn device\n"); |
213 | d94f9486 | aliguori | qemu_free(xendev); |
214 | d94f9486 | aliguori | return NULL; |
215 | d94f9486 | aliguori | } |
216 | d94f9486 | aliguori | fcntl(xc_evtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC); |
217 | d94f9486 | aliguori | |
218 | d94f9486 | aliguori | if (ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
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219 | d94f9486 | aliguori | xendev->gnttabdev = xc_gnttab_open(); |
220 | d94f9486 | aliguori | if (xendev->gnttabdev < 0) { |
221 | d94f9486 | aliguori | xen_be_printf(NULL, 0, "can't open gnttab device\n"); |
222 | d94f9486 | aliguori | xc_evtchn_close(xendev->evtchndev); |
223 | d94f9486 | aliguori | qemu_free(xendev); |
224 | d94f9486 | aliguori | return NULL; |
225 | d94f9486 | aliguori | } |
226 | d94f9486 | aliguori | } else {
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227 | d94f9486 | aliguori | xendev->gnttabdev = -1;
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228 | d94f9486 | aliguori | } |
229 | d94f9486 | aliguori | |
230 | d94f9486 | aliguori | TAILQ_INSERT_TAIL(&xendevs, xendev, next); |
231 | d94f9486 | aliguori | |
232 | d94f9486 | aliguori | if (xendev->ops->alloc)
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233 | d94f9486 | aliguori | xendev->ops->alloc(xendev); |
234 | d94f9486 | aliguori | |
235 | d94f9486 | aliguori | return xendev;
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236 | d94f9486 | aliguori | } |
237 | d94f9486 | aliguori | |
238 | d94f9486 | aliguori | /*
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239 | d94f9486 | aliguori | * release xen backend device.
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240 | d94f9486 | aliguori | */
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241 | d94f9486 | aliguori | static struct XenDevice *xen_be_del_xendev(int dom, int dev) |
242 | d94f9486 | aliguori | { |
243 | d94f9486 | aliguori | struct XenDevice *xendev, *xnext;
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244 | d94f9486 | aliguori | |
245 | d94f9486 | aliguori | /*
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246 | d94f9486 | aliguori | * This is pretty much like TAILQ_FOREACH(xendev, &xendevs, next) but
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247 | d94f9486 | aliguori | * we save the next pointer in xnext because we might free xendev.
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248 | d94f9486 | aliguori | */
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249 | d94f9486 | aliguori | xnext = xendevs.tqh_first; |
250 | d94f9486 | aliguori | while (xnext) {
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251 | d94f9486 | aliguori | xendev = xnext; |
252 | d94f9486 | aliguori | xnext = xendev->next.tqe_next; |
253 | d94f9486 | aliguori | |
254 | d94f9486 | aliguori | if (xendev->dom != dom)
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255 | d94f9486 | aliguori | continue;
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256 | d94f9486 | aliguori | if (xendev->dev != dev && dev != -1) |
257 | d94f9486 | aliguori | continue;
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258 | d94f9486 | aliguori | |
259 | d94f9486 | aliguori | if (xendev->ops->free)
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260 | d94f9486 | aliguori | xendev->ops->free(xendev); |
261 | d94f9486 | aliguori | |
262 | d94f9486 | aliguori | if (xendev->fe) {
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263 | d94f9486 | aliguori | char token[XEN_BUFSIZE];
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264 | d94f9486 | aliguori | snprintf(token, sizeof(token), "fe:%p", xendev); |
265 | d94f9486 | aliguori | xs_unwatch(xenstore, xendev->fe, token); |
266 | d94f9486 | aliguori | qemu_free(xendev->fe); |
267 | d94f9486 | aliguori | } |
268 | d94f9486 | aliguori | |
269 | d94f9486 | aliguori | if (xendev->evtchndev >= 0) |
270 | d94f9486 | aliguori | xc_evtchn_close(xendev->evtchndev); |
271 | d94f9486 | aliguori | if (xendev->gnttabdev >= 0) |
272 | d94f9486 | aliguori | xc_gnttab_close(xendev->gnttabdev); |
273 | d94f9486 | aliguori | |
274 | d94f9486 | aliguori | TAILQ_REMOVE(&xendevs, xendev, next); |
275 | d94f9486 | aliguori | qemu_free(xendev); |
276 | d94f9486 | aliguori | } |
277 | d94f9486 | aliguori | return NULL; |
278 | d94f9486 | aliguori | } |
279 | d94f9486 | aliguori | |
280 | d94f9486 | aliguori | /*
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281 | d94f9486 | aliguori | * Sync internal data structures on xenstore updates.
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282 | d94f9486 | aliguori | * Node specifies the changed field. node = NULL means
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283 | d94f9486 | aliguori | * update all fields (used for initialization).
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284 | d94f9486 | aliguori | */
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285 | d94f9486 | aliguori | static void xen_be_backend_changed(struct XenDevice *xendev, const char *node) |
286 | d94f9486 | aliguori | { |
287 | d94f9486 | aliguori | if (node == NULL || strcmp(node, "online") == 0) { |
288 | d94f9486 | aliguori | if (xenstore_read_be_int(xendev, "online", &xendev->online) == -1) |
289 | d94f9486 | aliguori | xendev->online = 0;
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290 | d94f9486 | aliguori | } |
291 | d94f9486 | aliguori | |
292 | d94f9486 | aliguori | if (node) {
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293 | d94f9486 | aliguori | xen_be_printf(xendev, 2, "backend update: %s\n", node); |
294 | d94f9486 | aliguori | if (xendev->ops->backend_changed)
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295 | d94f9486 | aliguori | xendev->ops->backend_changed(xendev, node); |
296 | d94f9486 | aliguori | } |
297 | d94f9486 | aliguori | } |
298 | d94f9486 | aliguori | |
299 | d94f9486 | aliguori | static void xen_be_frontend_changed(struct XenDevice *xendev, const char *node) |
300 | d94f9486 | aliguori | { |
301 | d94f9486 | aliguori | int fe_state;
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302 | d94f9486 | aliguori | |
303 | d94f9486 | aliguori | if (node == NULL || strcmp(node, "state") == 0) { |
304 | d94f9486 | aliguori | if (xenstore_read_fe_int(xendev, "state", &fe_state) == -1) |
305 | d94f9486 | aliguori | fe_state = XenbusStateUnknown; |
306 | d94f9486 | aliguori | if (xendev->fe_state != fe_state)
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307 | d94f9486 | aliguori | xen_be_printf(xendev, 1, "frontend state: %s -> %s\n", |
308 | d94f9486 | aliguori | xenbus_strstate(xendev->fe_state), |
309 | d94f9486 | aliguori | xenbus_strstate(fe_state)); |
310 | d94f9486 | aliguori | xendev->fe_state = fe_state; |
311 | d94f9486 | aliguori | } |
312 | d94f9486 | aliguori | if (node == NULL || strcmp(node, "protocol") == 0) { |
313 | d94f9486 | aliguori | qemu_free(xendev->protocol); |
314 | d94f9486 | aliguori | xendev->protocol = xenstore_read_fe_str(xendev, "protocol");
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315 | d94f9486 | aliguori | if (xendev->protocol)
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316 | d94f9486 | aliguori | xen_be_printf(xendev, 1, "frontend protocol: %s\n", xendev->protocol); |
317 | d94f9486 | aliguori | } |
318 | d94f9486 | aliguori | |
319 | d94f9486 | aliguori | if (node) {
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320 | d94f9486 | aliguori | xen_be_printf(xendev, 2, "frontend update: %s\n", node); |
321 | d94f9486 | aliguori | if (xendev->ops->frontend_changed)
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322 | d94f9486 | aliguori | xendev->ops->frontend_changed(xendev, node); |
323 | d94f9486 | aliguori | } |
324 | d94f9486 | aliguori | } |
325 | d94f9486 | aliguori | |
326 | d94f9486 | aliguori | /* ------------------------------------------------------------- */
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327 | d94f9486 | aliguori | /* Check for possible state transitions and perform them. */
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328 | d94f9486 | aliguori | |
329 | d94f9486 | aliguori | /*
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330 | d94f9486 | aliguori | * Initial xendev setup. Read frontend path, register watch for it.
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331 | d94f9486 | aliguori | * Should succeed once xend finished setting up the backend device.
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332 | d94f9486 | aliguori | *
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333 | d94f9486 | aliguori | * Also sets initial state (-> Initializing) when done. Which
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334 | d94f9486 | aliguori | * only affects the xendev->be_state variable as xenbus should
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335 | d94f9486 | aliguori | * already be put into that state by xend.
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336 | d94f9486 | aliguori | */
|
337 | d94f9486 | aliguori | static int xen_be_try_setup(struct XenDevice *xendev) |
338 | d94f9486 | aliguori | { |
339 | d94f9486 | aliguori | char token[XEN_BUFSIZE];
|
340 | d94f9486 | aliguori | int be_state;
|
341 | d94f9486 | aliguori | |
342 | d94f9486 | aliguori | if (xenstore_read_be_int(xendev, "state", &be_state) == -1) { |
343 | d94f9486 | aliguori | xen_be_printf(xendev, 0, "reading backend state failed\n"); |
344 | d94f9486 | aliguori | return -1; |
345 | d94f9486 | aliguori | } |
346 | d94f9486 | aliguori | |
347 | d94f9486 | aliguori | if (be_state != XenbusStateInitialising) {
|
348 | d94f9486 | aliguori | xen_be_printf(xendev, 0, "initial backend state is wrong (%s)\n", |
349 | d94f9486 | aliguori | xenbus_strstate(be_state)); |
350 | d94f9486 | aliguori | return -1; |
351 | d94f9486 | aliguori | } |
352 | d94f9486 | aliguori | |
353 | d94f9486 | aliguori | xendev->fe = xenstore_read_be_str(xendev, "frontend");
|
354 | d94f9486 | aliguori | if (xendev->fe == NULL) { |
355 | d94f9486 | aliguori | xen_be_printf(xendev, 0, "reading frontend path failed\n"); |
356 | d94f9486 | aliguori | return -1; |
357 | d94f9486 | aliguori | } |
358 | d94f9486 | aliguori | |
359 | d94f9486 | aliguori | /* setup frontend watch */
|
360 | d94f9486 | aliguori | snprintf(token, sizeof(token), "fe:%p", xendev); |
361 | d94f9486 | aliguori | if (!xs_watch(xenstore, xendev->fe, token)) {
|
362 | d94f9486 | aliguori | xen_be_printf(xendev, 0, "watching frontend path (%s) failed\n", |
363 | d94f9486 | aliguori | xendev->fe); |
364 | d94f9486 | aliguori | return -1; |
365 | d94f9486 | aliguori | } |
366 | d94f9486 | aliguori | xen_be_set_state(xendev, XenbusStateInitialising); |
367 | d94f9486 | aliguori | |
368 | d94f9486 | aliguori | xen_be_backend_changed(xendev, NULL);
|
369 | d94f9486 | aliguori | xen_be_frontend_changed(xendev, NULL);
|
370 | d94f9486 | aliguori | return 0; |
371 | d94f9486 | aliguori | } |
372 | d94f9486 | aliguori | |
373 | d94f9486 | aliguori | /*
|
374 | d94f9486 | aliguori | * Try initialize xendev. Prepare everything the backend can do
|
375 | d94f9486 | aliguori | * without synchronizing with the frontend. Fakes hotplug-status. No
|
376 | d94f9486 | aliguori | * hotplug involved here because this is about userspace drivers, thus
|
377 | d94f9486 | aliguori | * there are kernel backend devices which could invoke hotplug.
|
378 | d94f9486 | aliguori | *
|
379 | d94f9486 | aliguori | * Goes to InitWait on success.
|
380 | d94f9486 | aliguori | */
|
381 | d94f9486 | aliguori | static int xen_be_try_init(struct XenDevice *xendev) |
382 | d94f9486 | aliguori | { |
383 | d94f9486 | aliguori | int rc = 0; |
384 | d94f9486 | aliguori | |
385 | d94f9486 | aliguori | if (!xendev->online) {
|
386 | d94f9486 | aliguori | xen_be_printf(xendev, 1, "not online\n"); |
387 | d94f9486 | aliguori | return -1; |
388 | d94f9486 | aliguori | } |
389 | d94f9486 | aliguori | |
390 | d94f9486 | aliguori | if (xendev->ops->init)
|
391 | d94f9486 | aliguori | rc = xendev->ops->init(xendev); |
392 | d94f9486 | aliguori | if (rc != 0) { |
393 | d94f9486 | aliguori | xen_be_printf(xendev, 1, "init() failed\n"); |
394 | d94f9486 | aliguori | return rc;
|
395 | d94f9486 | aliguori | } |
396 | d94f9486 | aliguori | |
397 | d94f9486 | aliguori | xenstore_write_be_str(xendev, "hotplug-status", "connected"); |
398 | d94f9486 | aliguori | xen_be_set_state(xendev, XenbusStateInitWait); |
399 | d94f9486 | aliguori | return 0; |
400 | d94f9486 | aliguori | } |
401 | d94f9486 | aliguori | |
402 | d94f9486 | aliguori | /*
|
403 | d94f9486 | aliguori | * Try to connect xendev. Depends on the frontend being ready
|
404 | d94f9486 | aliguori | * for it (shared ring and evtchn info in xenstore, state being
|
405 | d94f9486 | aliguori | * Initialised or Connected).
|
406 | d94f9486 | aliguori | *
|
407 | d94f9486 | aliguori | * Goes to Connected on success.
|
408 | d94f9486 | aliguori | */
|
409 | d94f9486 | aliguori | static int xen_be_try_connect(struct XenDevice *xendev) |
410 | d94f9486 | aliguori | { |
411 | d94f9486 | aliguori | int rc = 0; |
412 | d94f9486 | aliguori | |
413 | d94f9486 | aliguori | if (xendev->fe_state != XenbusStateInitialised &&
|
414 | d94f9486 | aliguori | xendev->fe_state != XenbusStateConnected) { |
415 | d94f9486 | aliguori | if (xendev->ops->flags & DEVOPS_FLAG_IGNORE_STATE) {
|
416 | d94f9486 | aliguori | xen_be_printf(xendev, 2, "frontend not ready, ignoring\n"); |
417 | d94f9486 | aliguori | } else {
|
418 | d94f9486 | aliguori | xen_be_printf(xendev, 2, "frontend not ready (yet)\n"); |
419 | d94f9486 | aliguori | return -1; |
420 | d94f9486 | aliguori | } |
421 | d94f9486 | aliguori | } |
422 | d94f9486 | aliguori | |
423 | d94f9486 | aliguori | if (xendev->ops->connect)
|
424 | d94f9486 | aliguori | rc = xendev->ops->connect(xendev); |
425 | d94f9486 | aliguori | if (rc != 0) { |
426 | d94f9486 | aliguori | xen_be_printf(xendev, 0, "connect() failed\n"); |
427 | d94f9486 | aliguori | return rc;
|
428 | d94f9486 | aliguori | } |
429 | d94f9486 | aliguori | |
430 | d94f9486 | aliguori | xen_be_set_state(xendev, XenbusStateConnected); |
431 | d94f9486 | aliguori | return 0; |
432 | d94f9486 | aliguori | } |
433 | d94f9486 | aliguori | |
434 | d94f9486 | aliguori | /*
|
435 | d94f9486 | aliguori | * Teardown connection.
|
436 | d94f9486 | aliguori | *
|
437 | d94f9486 | aliguori | * Goes to Closed when done.
|
438 | d94f9486 | aliguori | */
|
439 | d94f9486 | aliguori | static void xen_be_disconnect(struct XenDevice *xendev, enum xenbus_state state) |
440 | d94f9486 | aliguori | { |
441 | d94f9486 | aliguori | if (xendev->be_state != XenbusStateClosing &&
|
442 | d94f9486 | aliguori | xendev->be_state != XenbusStateClosed && |
443 | d94f9486 | aliguori | xendev->ops->disconnect) |
444 | d94f9486 | aliguori | xendev->ops->disconnect(xendev); |
445 | d94f9486 | aliguori | if (xendev->be_state != state)
|
446 | d94f9486 | aliguori | xen_be_set_state(xendev, state); |
447 | d94f9486 | aliguori | } |
448 | d94f9486 | aliguori | |
449 | d94f9486 | aliguori | /*
|
450 | d94f9486 | aliguori | * Try to reset xendev, for reconnection by another frontend instance.
|
451 | d94f9486 | aliguori | */
|
452 | d94f9486 | aliguori | static int xen_be_try_reset(struct XenDevice *xendev) |
453 | d94f9486 | aliguori | { |
454 | d94f9486 | aliguori | if (xendev->fe_state != XenbusStateInitialising)
|
455 | d94f9486 | aliguori | return -1; |
456 | d94f9486 | aliguori | |
457 | d94f9486 | aliguori | xen_be_printf(xendev, 1, "device reset (for re-connect)\n"); |
458 | d94f9486 | aliguori | xen_be_set_state(xendev, XenbusStateInitialising); |
459 | d94f9486 | aliguori | return 0; |
460 | d94f9486 | aliguori | } |
461 | d94f9486 | aliguori | |
462 | d94f9486 | aliguori | /*
|
463 | d94f9486 | aliguori | * state change dispatcher function
|
464 | d94f9486 | aliguori | */
|
465 | d94f9486 | aliguori | void xen_be_check_state(struct XenDevice *xendev) |
466 | d94f9486 | aliguori | { |
467 | d94f9486 | aliguori | int rc = 0; |
468 | d94f9486 | aliguori | |
469 | d94f9486 | aliguori | /* frontend may request shutdown from almost anywhere */
|
470 | d94f9486 | aliguori | if (xendev->fe_state == XenbusStateClosing ||
|
471 | d94f9486 | aliguori | xendev->fe_state == XenbusStateClosed) { |
472 | d94f9486 | aliguori | xen_be_disconnect(xendev, xendev->fe_state); |
473 | d94f9486 | aliguori | return;
|
474 | d94f9486 | aliguori | } |
475 | d94f9486 | aliguori | |
476 | d94f9486 | aliguori | /* check for possible backend state transitions */
|
477 | d94f9486 | aliguori | for (;;) {
|
478 | d94f9486 | aliguori | switch (xendev->be_state) {
|
479 | d94f9486 | aliguori | case XenbusStateUnknown:
|
480 | d94f9486 | aliguori | rc = xen_be_try_setup(xendev); |
481 | d94f9486 | aliguori | break;
|
482 | d94f9486 | aliguori | case XenbusStateInitialising:
|
483 | d94f9486 | aliguori | rc = xen_be_try_init(xendev); |
484 | d94f9486 | aliguori | break;
|
485 | d94f9486 | aliguori | case XenbusStateInitWait:
|
486 | d94f9486 | aliguori | rc = xen_be_try_connect(xendev); |
487 | d94f9486 | aliguori | break;
|
488 | d94f9486 | aliguori | case XenbusStateClosed:
|
489 | d94f9486 | aliguori | rc = xen_be_try_reset(xendev); |
490 | d94f9486 | aliguori | break;
|
491 | d94f9486 | aliguori | default:
|
492 | d94f9486 | aliguori | rc = -1;
|
493 | d94f9486 | aliguori | } |
494 | d94f9486 | aliguori | if (rc != 0) |
495 | d94f9486 | aliguori | break;
|
496 | d94f9486 | aliguori | } |
497 | d94f9486 | aliguori | } |
498 | d94f9486 | aliguori | |
499 | d94f9486 | aliguori | /* ------------------------------------------------------------- */
|
500 | d94f9486 | aliguori | |
501 | d94f9486 | aliguori | static int xenstore_scan(const char *type, int dom, struct XenDevOps *ops) |
502 | d94f9486 | aliguori | { |
503 | d94f9486 | aliguori | struct XenDevice *xendev;
|
504 | d94f9486 | aliguori | char path[XEN_BUFSIZE], token[XEN_BUFSIZE];
|
505 | d94f9486 | aliguori | char **dev = NULL, *dom0; |
506 | d94f9486 | aliguori | unsigned int cdev, j; |
507 | d94f9486 | aliguori | |
508 | d94f9486 | aliguori | /* setup watch */
|
509 | d94f9486 | aliguori | dom0 = xs_get_domain_path(xenstore, 0);
|
510 | d94f9486 | aliguori | snprintf(token, sizeof(token), "be:%p:%d:%p", type, dom, ops); |
511 | d94f9486 | aliguori | snprintf(path, sizeof(path), "%s/backend/%s/%d", dom0, type, dom); |
512 | d94f9486 | aliguori | free(dom0); |
513 | d94f9486 | aliguori | if (!xs_watch(xenstore, path, token)) {
|
514 | d94f9486 | aliguori | xen_be_printf(NULL, 0, "xen be: watching backend path (%s) failed\n", path); |
515 | d94f9486 | aliguori | return -1; |
516 | d94f9486 | aliguori | } |
517 | d94f9486 | aliguori | |
518 | d94f9486 | aliguori | /* look for backends */
|
519 | d94f9486 | aliguori | dev = xs_directory(xenstore, 0, path, &cdev);
|
520 | d94f9486 | aliguori | if (!dev)
|
521 | d94f9486 | aliguori | return 0; |
522 | d94f9486 | aliguori | for (j = 0; j < cdev; j++) { |
523 | d94f9486 | aliguori | xendev = xen_be_get_xendev(type, dom, atoi(dev[j]), ops); |
524 | d94f9486 | aliguori | if (xendev == NULL) |
525 | d94f9486 | aliguori | continue;
|
526 | d94f9486 | aliguori | xen_be_check_state(xendev); |
527 | d94f9486 | aliguori | } |
528 | d94f9486 | aliguori | free(dev); |
529 | d94f9486 | aliguori | return 0; |
530 | d94f9486 | aliguori | } |
531 | d94f9486 | aliguori | |
532 | d94f9486 | aliguori | static void xenstore_update_be(char *watch, char *type, int dom, |
533 | d94f9486 | aliguori | struct XenDevOps *ops)
|
534 | d94f9486 | aliguori | { |
535 | d94f9486 | aliguori | struct XenDevice *xendev;
|
536 | d94f9486 | aliguori | char path[XEN_BUFSIZE], *dom0;
|
537 | d94f9486 | aliguori | unsigned int len, dev; |
538 | d94f9486 | aliguori | |
539 | d94f9486 | aliguori | dom0 = xs_get_domain_path(xenstore, 0);
|
540 | d94f9486 | aliguori | len = snprintf(path, sizeof(path), "%s/backend/%s/%d", dom0, type, dom); |
541 | d94f9486 | aliguori | free(dom0); |
542 | d94f9486 | aliguori | if (strncmp(path, watch, len) != 0) |
543 | d94f9486 | aliguori | return;
|
544 | d94f9486 | aliguori | if (sscanf(watch+len, "/%u/%255s", &dev, path) != 2) { |
545 | d94f9486 | aliguori | strcpy(path, "");
|
546 | d94f9486 | aliguori | if (sscanf(watch+len, "/%u", &dev) != 1) |
547 | d94f9486 | aliguori | dev = -1;
|
548 | d94f9486 | aliguori | } |
549 | d94f9486 | aliguori | if (dev == -1) |
550 | d94f9486 | aliguori | return;
|
551 | d94f9486 | aliguori | |
552 | d94f9486 | aliguori | if (0) { |
553 | d94f9486 | aliguori | /* FIXME: detect devices being deleted from xenstore ... */
|
554 | d94f9486 | aliguori | xen_be_del_xendev(dom, dev); |
555 | d94f9486 | aliguori | } |
556 | d94f9486 | aliguori | |
557 | d94f9486 | aliguori | xendev = xen_be_get_xendev(type, dom, dev, ops); |
558 | d94f9486 | aliguori | if (xendev != NULL) { |
559 | d94f9486 | aliguori | xen_be_backend_changed(xendev, path); |
560 | d94f9486 | aliguori | xen_be_check_state(xendev); |
561 | d94f9486 | aliguori | } |
562 | d94f9486 | aliguori | } |
563 | d94f9486 | aliguori | |
564 | d94f9486 | aliguori | static void xenstore_update_fe(char *watch, struct XenDevice *xendev) |
565 | d94f9486 | aliguori | { |
566 | d94f9486 | aliguori | char *node;
|
567 | d94f9486 | aliguori | unsigned int len; |
568 | d94f9486 | aliguori | |
569 | d94f9486 | aliguori | len = strlen(xendev->fe); |
570 | d94f9486 | aliguori | if (strncmp(xendev->fe, watch, len) != 0) |
571 | d94f9486 | aliguori | return;
|
572 | d94f9486 | aliguori | if (watch[len] != '/') |
573 | d94f9486 | aliguori | return;
|
574 | d94f9486 | aliguori | node = watch + len + 1;
|
575 | d94f9486 | aliguori | |
576 | d94f9486 | aliguori | xen_be_frontend_changed(xendev, node); |
577 | d94f9486 | aliguori | xen_be_check_state(xendev); |
578 | d94f9486 | aliguori | } |
579 | d94f9486 | aliguori | |
580 | d94f9486 | aliguori | static void xenstore_update(void *unused) |
581 | d94f9486 | aliguori | { |
582 | d94f9486 | aliguori | char **vec = NULL; |
583 | d94f9486 | aliguori | intptr_t type, ops, ptr; |
584 | d94f9486 | aliguori | unsigned int dom, count; |
585 | d94f9486 | aliguori | |
586 | d94f9486 | aliguori | vec = xs_read_watch(xenstore, &count); |
587 | d94f9486 | aliguori | if (vec == NULL) |
588 | d94f9486 | aliguori | goto cleanup;
|
589 | d94f9486 | aliguori | |
590 | d94f9486 | aliguori | if (sscanf(vec[XS_WATCH_TOKEN], "be:%" PRIxPTR ":%d:%" PRIxPTR, |
591 | d94f9486 | aliguori | &type, &dom, &ops) == 3)
|
592 | d94f9486 | aliguori | xenstore_update_be(vec[XS_WATCH_PATH], (void*)type, dom, (void*)ops); |
593 | d94f9486 | aliguori | if (sscanf(vec[XS_WATCH_TOKEN], "fe:%" PRIxPTR, &ptr) == 1) |
594 | d94f9486 | aliguori | xenstore_update_fe(vec[XS_WATCH_PATH], (void*)ptr);
|
595 | d94f9486 | aliguori | |
596 | d94f9486 | aliguori | cleanup:
|
597 | d94f9486 | aliguori | qemu_free(vec); |
598 | d94f9486 | aliguori | } |
599 | d94f9486 | aliguori | |
600 | d94f9486 | aliguori | static void xen_be_evtchn_event(void *opaque) |
601 | d94f9486 | aliguori | { |
602 | d94f9486 | aliguori | struct XenDevice *xendev = opaque;
|
603 | d94f9486 | aliguori | evtchn_port_t port; |
604 | d94f9486 | aliguori | |
605 | d94f9486 | aliguori | port = xc_evtchn_pending(xendev->evtchndev); |
606 | d94f9486 | aliguori | if (port != xendev->local_port) {
|
607 | d94f9486 | aliguori | xen_be_printf(xendev, 0, "xc_evtchn_pending returned %d (expected %d)\n", |
608 | d94f9486 | aliguori | port, xendev->local_port); |
609 | d94f9486 | aliguori | return;
|
610 | d94f9486 | aliguori | } |
611 | d94f9486 | aliguori | xc_evtchn_unmask(xendev->evtchndev, port); |
612 | d94f9486 | aliguori | |
613 | d94f9486 | aliguori | if (xendev->ops->event)
|
614 | d94f9486 | aliguori | xendev->ops->event(xendev); |
615 | d94f9486 | aliguori | } |
616 | d94f9486 | aliguori | |
617 | d94f9486 | aliguori | /* -------------------------------------------------------------------- */
|
618 | d94f9486 | aliguori | |
619 | d94f9486 | aliguori | int xen_be_init(void) |
620 | d94f9486 | aliguori | { |
621 | d94f9486 | aliguori | xenstore = xs_daemon_open(); |
622 | d94f9486 | aliguori | if (!xenstore) {
|
623 | d94f9486 | aliguori | xen_be_printf(NULL, 0, "can't connect to xenstored\n"); |
624 | d94f9486 | aliguori | return -1; |
625 | d94f9486 | aliguori | } |
626 | d94f9486 | aliguori | |
627 | d94f9486 | aliguori | if (qemu_set_fd_handler(xs_fileno(xenstore), xenstore_update, NULL, NULL) < 0) |
628 | d94f9486 | aliguori | goto err;
|
629 | d94f9486 | aliguori | |
630 | d94f9486 | aliguori | xen_xc = xc_interface_open(); |
631 | d94f9486 | aliguori | if (xen_xc == -1) { |
632 | d94f9486 | aliguori | xen_be_printf(NULL, 0, "can't open xen interface\n"); |
633 | d94f9486 | aliguori | goto err;
|
634 | d94f9486 | aliguori | } |
635 | d94f9486 | aliguori | return 0; |
636 | d94f9486 | aliguori | |
637 | d94f9486 | aliguori | err:
|
638 | d94f9486 | aliguori | qemu_set_fd_handler(xs_fileno(xenstore), NULL, NULL, NULL); |
639 | d94f9486 | aliguori | xs_daemon_close(xenstore); |
640 | d94f9486 | aliguori | xenstore = NULL;
|
641 | d94f9486 | aliguori | |
642 | d94f9486 | aliguori | return -1; |
643 | d94f9486 | aliguori | } |
644 | d94f9486 | aliguori | |
645 | d94f9486 | aliguori | int xen_be_register(const char *type, struct XenDevOps *ops) |
646 | d94f9486 | aliguori | { |
647 | d94f9486 | aliguori | return xenstore_scan(type, xen_domid, ops);
|
648 | d94f9486 | aliguori | } |
649 | d94f9486 | aliguori | |
650 | d94f9486 | aliguori | int xen_be_bind_evtchn(struct XenDevice *xendev) |
651 | d94f9486 | aliguori | { |
652 | d94f9486 | aliguori | if (xendev->local_port != -1) |
653 | d94f9486 | aliguori | return 0; |
654 | d94f9486 | aliguori | xendev->local_port = xc_evtchn_bind_interdomain |
655 | d94f9486 | aliguori | (xendev->evtchndev, xendev->dom, xendev->remote_port); |
656 | d94f9486 | aliguori | if (xendev->local_port == -1) { |
657 | d94f9486 | aliguori | xen_be_printf(xendev, 0, "xc_evtchn_bind_interdomain failed\n"); |
658 | d94f9486 | aliguori | return -1; |
659 | d94f9486 | aliguori | } |
660 | d94f9486 | aliguori | xen_be_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port); |
661 | d94f9486 | aliguori | qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev), |
662 | d94f9486 | aliguori | xen_be_evtchn_event, NULL, xendev);
|
663 | d94f9486 | aliguori | return 0; |
664 | d94f9486 | aliguori | } |
665 | d94f9486 | aliguori | |
666 | d94f9486 | aliguori | void xen_be_unbind_evtchn(struct XenDevice *xendev) |
667 | d94f9486 | aliguori | { |
668 | d94f9486 | aliguori | if (xendev->local_port == -1) |
669 | d94f9486 | aliguori | return;
|
670 | d94f9486 | aliguori | qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev), NULL, NULL, NULL); |
671 | d94f9486 | aliguori | xc_evtchn_unbind(xendev->evtchndev, xendev->local_port); |
672 | d94f9486 | aliguori | xen_be_printf(xendev, 2, "unbind evtchn port %d\n", xendev->local_port); |
673 | d94f9486 | aliguori | xendev->local_port = -1;
|
674 | d94f9486 | aliguori | } |
675 | d94f9486 | aliguori | |
676 | d94f9486 | aliguori | int xen_be_send_notify(struct XenDevice *xendev) |
677 | d94f9486 | aliguori | { |
678 | d94f9486 | aliguori | return xc_evtchn_notify(xendev->evtchndev, xendev->local_port);
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679 | d94f9486 | aliguori | } |
680 | d94f9486 | aliguori | |
681 | d94f9486 | aliguori | /*
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682 | d94f9486 | aliguori | * msg_level:
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683 | d94f9486 | aliguori | * 0 == errors (stderr + logfile).
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684 | d94f9486 | aliguori | * 1 == informative debug messages (logfile only).
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685 | d94f9486 | aliguori | * 2 == noisy debug messages (logfile only).
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686 | d94f9486 | aliguori | * 3 == will flood your log (logfile only).
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687 | d94f9486 | aliguori | */
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688 | d94f9486 | aliguori | void xen_be_printf(struct XenDevice *xendev, int msg_level, const char *fmt, ...) |
689 | d94f9486 | aliguori | { |
690 | d94f9486 | aliguori | va_list args; |
691 | d94f9486 | aliguori | |
692 | d94f9486 | aliguori | if (xendev) {
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693 | d94f9486 | aliguori | if (msg_level > xendev->debug)
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694 | d94f9486 | aliguori | return;
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695 | d94f9486 | aliguori | qemu_log("xen be: %s: ", xendev->name);
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696 | d94f9486 | aliguori | if (msg_level == 0) |
697 | d94f9486 | aliguori | fprintf(stderr, "xen be: %s: ", xendev->name);
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698 | d94f9486 | aliguori | } else {
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699 | d94f9486 | aliguori | if (msg_level > debug)
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700 | d94f9486 | aliguori | return;
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701 | d94f9486 | aliguori | qemu_log("xen be core: ");
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702 | d94f9486 | aliguori | if (msg_level == 0) |
703 | d94f9486 | aliguori | fprintf(stderr, "xen be core: ");
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704 | d94f9486 | aliguori | } |
705 | d94f9486 | aliguori | va_start(args, fmt); |
706 | d94f9486 | aliguori | qemu_log_vprintf(fmt, args); |
707 | d94f9486 | aliguori | va_end(args); |
708 | d94f9486 | aliguori | if (msg_level == 0) { |
709 | d94f9486 | aliguori | va_start(args, fmt); |
710 | d94f9486 | aliguori | vfprintf(stderr, fmt, args); |
711 | d94f9486 | aliguori | va_end(args); |
712 | d94f9486 | aliguori | } |
713 | d94f9486 | aliguori | qemu_log_flush(); |
714 | d94f9486 | aliguori | } |