1 /*
2  * Copyright (C) 2014       Citrix Systems UK Ltd.
3  *
4  * This work is licensed under the terms of the GNU GPL, version 2.  See
5  * the COPYING file in the top-level directory.
6  *
7  * Contributions after 2012-01-13 are licensed under the terms of the
8  * GNU GPL, version 2 or (at your option) any later version.
9  */
10 
11 #include "qemu/osdep.h"
12 #include "qemu/error-report.h"
13 #include "qemu/module.h"
14 #include "hw/xen/xen-legacy-backend.h"
15 #include "chardev/char.h"
16 #include "sysemu/accel.h"
17 #include "sysemu/runstate.h"
18 #include "migration/misc.h"
19 #include "migration/global_state.h"
20 
21 //#define DEBUG_XEN
22 
23 #ifdef DEBUG_XEN
24 #define DPRINTF(fmt, ...) \
25     do { fprintf(stderr, "xen: " fmt, ## __VA_ARGS__); } while (0)
26 #else
27 #define DPRINTF(fmt, ...) \
28     do { } while (0)
29 #endif
30 
31 xc_interface *xen_xc;
32 xenforeignmemory_handle *xen_fmem;
33 xendevicemodel_handle *xen_dmod;
34 
store_dev_info(int domid,Chardev * cs,const char * string)35 static int store_dev_info(int domid, Chardev *cs, const char *string)
36 {
37     struct xs_handle *xs = NULL;
38     char *path = NULL;
39     char *newpath = NULL;
40     char *pts = NULL;
41     int ret = -1;
42 
43     /* Only continue if we're talking to a pty. */
44     if (!CHARDEV_IS_PTY(cs)) {
45         return 0;
46     }
47     pts = cs->filename + 4;
48 
49     /* We now have everything we need to set the xenstore entry. */
50     xs = xs_open(0);
51     if (xs == NULL) {
52         fprintf(stderr, "Could not contact XenStore\n");
53         goto out;
54     }
55 
56     path = xs_get_domain_path(xs, domid);
57     if (path == NULL) {
58         fprintf(stderr, "xs_get_domain_path() error\n");
59         goto out;
60     }
61     newpath = realloc(path, (strlen(path) + strlen(string) +
62                 strlen("/tty") + 1));
63     if (newpath == NULL) {
64         fprintf(stderr, "realloc error\n");
65         goto out;
66     }
67     path = newpath;
68 
69     strcat(path, string);
70     strcat(path, "/tty");
71     if (!xs_write(xs, XBT_NULL, path, pts, strlen(pts))) {
72         fprintf(stderr, "xs_write for '%s' fail", string);
73         goto out;
74     }
75     ret = 0;
76 
77 out:
78     free(path);
79     xs_close(xs);
80 
81     return ret;
82 }
83 
xenstore_store_pv_console_info(int i,Chardev * chr)84 void xenstore_store_pv_console_info(int i, Chardev *chr)
85 {
86     if (i == 0) {
87         store_dev_info(xen_domid, chr, "/console");
88     } else {
89         char buf[32];
90         snprintf(buf, sizeof(buf), "/device/console/%d", i);
91         store_dev_info(xen_domid, chr, buf);
92     }
93 }
94 
95 
xenstore_record_dm_state(struct xs_handle * xs,const char * state)96 static void xenstore_record_dm_state(struct xs_handle *xs, const char *state)
97 {
98     char path[50];
99 
100     if (xs == NULL) {
101         error_report("xenstore connection not initialized");
102         exit(1);
103     }
104 
105     snprintf(path, sizeof (path), "device-model/%u/state", xen_domid);
106     /*
107      * This call may fail when running restricted so don't make it fatal in
108      * that case. Toolstacks should instead use QMP to listen for state changes.
109      */
110     if (!xs_write(xs, XBT_NULL, path, state, strlen(state)) &&
111             !xen_domid_restrict) {
112         error_report("error recording dm state");
113         exit(1);
114     }
115 }
116 
117 
xen_change_state_handler(void * opaque,int running,RunState state)118 static void xen_change_state_handler(void *opaque, int running,
119                                      RunState state)
120 {
121     if (running) {
122         /* record state running */
123         xenstore_record_dm_state(xenstore, "running");
124     }
125 }
126 
xen_setup_post(MachineState * ms,AccelState * accel)127 static void xen_setup_post(MachineState *ms, AccelState *accel)
128 {
129     int rc;
130 
131     if (xen_domid_restrict) {
132         rc = xen_restrict(xen_domid);
133         if (rc < 0) {
134             perror("xen: failed to restrict");
135             exit(1);
136         }
137     }
138 }
139 
xen_init(MachineState * ms)140 static int xen_init(MachineState *ms)
141 {
142     xen_xc = xc_interface_open(0, 0, 0);
143     if (xen_xc == NULL) {
144         xen_pv_printf(NULL, 0, "can't open xen interface\n");
145         return -1;
146     }
147     xen_fmem = xenforeignmemory_open(0, 0);
148     if (xen_fmem == NULL) {
149         xen_pv_printf(NULL, 0, "can't open xen fmem interface\n");
150         xc_interface_close(xen_xc);
151         return -1;
152     }
153     xen_dmod = xendevicemodel_open(0, 0);
154     if (xen_dmod == NULL) {
155         xen_pv_printf(NULL, 0, "can't open xen devicemodel interface\n");
156         xenforeignmemory_close(xen_fmem);
157         xc_interface_close(xen_xc);
158         return -1;
159     }
160     qemu_add_vm_change_state_handler(xen_change_state_handler, NULL);
161     return 0;
162 }
163 
xen_accel_class_init(ObjectClass * oc,void * data)164 static void xen_accel_class_init(ObjectClass *oc, void *data)
165 {
166     AccelClass *ac = ACCEL_CLASS(oc);
167     static GlobalProperty compat[] = {
168         { "migration", "store-global-state", "off" },
169         { "migration", "send-configuration", "off" },
170         { "migration", "send-section-footer", "off" },
171     };
172 
173     ac->name = "Xen";
174     ac->init_machine = xen_init;
175     ac->setup_post = xen_setup_post;
176     ac->allowed = &xen_allowed;
177     ac->compat_props = g_ptr_array_new();
178 
179     compat_props_add(ac->compat_props, compat, G_N_ELEMENTS(compat));
180 }
181 
182 #define TYPE_XEN_ACCEL ACCEL_CLASS_NAME("xen")
183 
184 static const TypeInfo xen_accel_type = {
185     .name = TYPE_XEN_ACCEL,
186     .parent = TYPE_ACCEL,
187     .class_init = xen_accel_class_init,
188 };
189 
xen_type_init(void)190 static void xen_type_init(void)
191 {
192     type_register_static(&xen_accel_type);
193 }
194 
195 type_init(xen_type_init);
196