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1/*
2 * xen console driver interface to hvc_console.c
3 *
4 * (c) 2007 Gerd Hoffmann <kraxel@suse.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/console.h>
22#include <linux/delay.h>
23#include <linux/err.h>
24#include <linux/init.h>
25#include <linux/types.h>
26
27#include <asm/xen/hypervisor.h>
28
29#include <xen/xen.h>
30#include <xen/page.h>
31#include <xen/events.h>
32#include <xen/interface/io/console.h>
33#include <xen/hvc-console.h>
34
35#include "hvc_console.h"
36
37#define HVC_COOKIE 0x58656e /* "Xen" in hex */
38
39static struct hvc_struct *hvc;
40static int xencons_irq;
41
42/* ------------------------------------------------------------------ */
43
44static unsigned long console_pfn = ~0ul;
45
46static inline struct xencons_interface *xencons_interface(void)
47{
48 if (console_pfn == ~0ul)
49 return mfn_to_virt(xen_start_info->console.domU.mfn);
50 else
51 return __va(console_pfn << PAGE_SHIFT);
52}
53
54static inline void notify_daemon(void)
55{
56 /* Use evtchn: this is called early, before irq is set up. */
57 notify_remote_via_evtchn(xen_start_info->console.domU.evtchn);
58}
59
60static int __write_console(const char *data, int len)
61{
62 struct xencons_interface *intf = xencons_interface();
63 XENCONS_RING_IDX cons, prod;
64 int sent = 0;
65
66 cons = intf->out_cons;
67 prod = intf->out_prod;
68 mb(); /* update queue values before going on */
69 BUG_ON((prod - cons) > sizeof(intf->out));
70
71 while ((sent < len) && ((prod - cons) < sizeof(intf->out)))
72 intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++];
73
74 wmb(); /* write ring before updating pointer */
75 intf->out_prod = prod;
76
77 if (sent)
78 notify_daemon();
79 return sent;
80}
81
82static int domU_write_console(uint32_t vtermno, const char *data, int len)
83{
84 int ret = len;
85
86 /*
87 * Make sure the whole buffer is emitted, polling if
88 * necessary. We don't ever want to rely on the hvc daemon
89 * because the most interesting console output is when the
90 * kernel is crippled.
91 */
92 while (len) {
93 int sent = __write_console(data, len);
94
95 data += sent;
96 len -= sent;
97
98 if (unlikely(len))
99 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
100 }
101
102 return ret;
103}
104
105static int domU_read_console(uint32_t vtermno, char *buf, int len)
106{
107 struct xencons_interface *intf = xencons_interface();
108 XENCONS_RING_IDX cons, prod;
109 int recv = 0;
110
111 cons = intf->in_cons;
112 prod = intf->in_prod;
113 mb(); /* get pointers before reading ring */
114 BUG_ON((prod - cons) > sizeof(intf->in));
115
116 while (cons != prod && recv < len)
117 buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)];
118
119 mb(); /* read ring before consuming */
120 intf->in_cons = cons;
121
122 notify_daemon();
123 return recv;
124}
125
126static struct hv_ops domU_hvc_ops = {
127 .get_chars = domU_read_console,
128 .put_chars = domU_write_console,
129 .notifier_add = notifier_add_irq,
130 .notifier_del = notifier_del_irq,
131 .notifier_hangup = notifier_hangup_irq,
132};
133
134static int dom0_read_console(uint32_t vtermno, char *buf, int len)
135{
136 return HYPERVISOR_console_io(CONSOLEIO_read, len, buf);
137}
138
139/*
140 * Either for a dom0 to write to the system console, or a domU with a
141 * debug version of Xen
142 */
143static int dom0_write_console(uint32_t vtermno, const char *str, int len)
144{
145 int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str);
146 if (rc < 0)
147 return 0;
148
149 return len;
150}
151
152static struct hv_ops dom0_hvc_ops = {
153 .get_chars = dom0_read_console,
154 .put_chars = dom0_write_console,
155 .notifier_add = notifier_add_irq,
156 .notifier_del = notifier_del_irq,
157 .notifier_hangup = notifier_hangup_irq,
158};
159
160static int __init xen_hvc_init(void)
161{
162 struct hvc_struct *hp;
163 struct hv_ops *ops;
164
165 if (!xen_pv_domain())
166 return -ENODEV;
167
168 if (xen_initial_domain()) {
169 ops = &dom0_hvc_ops;
170 xencons_irq = bind_virq_to_irq(VIRQ_CONSOLE, 0);
171 } else {
172 if (!xen_start_info->console.domU.evtchn)
173 return -ENODEV;
174
175 ops = &domU_hvc_ops;
176 xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
177 }
178 if (xencons_irq < 0)
179 xencons_irq = 0; /* NO_IRQ */
180 else
181 irq_set_noprobe(xencons_irq);
182
183 hp = hvc_alloc(HVC_COOKIE, xencons_irq, ops, 256);
184 if (IS_ERR(hp))
185 return PTR_ERR(hp);
186
187 hvc = hp;
188
189 console_pfn = mfn_to_pfn(xen_start_info->console.domU.mfn);
190
191 return 0;
192}
193
194void xen_console_resume(void)
195{
196 if (xencons_irq)
197 rebind_evtchn_irq(xen_start_info->console.domU.evtchn, xencons_irq);
198}
199
200static void __exit xen_hvc_fini(void)
201{
202 if (hvc)
203 hvc_remove(hvc);
204}
205
206static int xen_cons_init(void)
207{
208 struct hv_ops *ops;
209
210 if (!xen_pv_domain())
211 return 0;
212
213 if (xen_initial_domain())
214 ops = &dom0_hvc_ops;
215 else
216 ops = &domU_hvc_ops;
217
218 hvc_instantiate(HVC_COOKIE, 0, ops);
219 return 0;
220}
221
222module_init(xen_hvc_init);
223module_exit(xen_hvc_fini);
224console_initcall(xen_cons_init);
225
226#ifdef CONFIG_EARLY_PRINTK
227static void xenboot_write_console(struct console *console, const char *string,
228 unsigned len)
229{
230 unsigned int linelen, off = 0;
231 const char *pos;
232
233 dom0_write_console(0, string, len);
234
235 if (xen_initial_domain())
236 return;
237
238 domU_write_console(0, "(early) ", 8);
239 while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
240 linelen = pos-string+off;
241 if (off + linelen > len)
242 break;
243 domU_write_console(0, string+off, linelen);
244 domU_write_console(0, "\r\n", 2);
245 off += linelen + 1;
246 }
247 if (off < len)
248 domU_write_console(0, string+off, len-off);
249}
250
251struct console xenboot_console = {
252 .name = "xenboot",
253 .write = xenboot_write_console,
254 .flags = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
255};
256#endif /* CONFIG_EARLY_PRINTK */
257
258void xen_raw_console_write(const char *str)
259{
260 dom0_write_console(0, str, strlen(str));
261}
262
263void xen_raw_printk(const char *fmt, ...)
264{
265 static char buf[512];
266 va_list ap;
267
268 va_start(ap, fmt);
269 vsnprintf(buf, sizeof(buf), fmt, ap);
270 va_end(ap);
271
272 xen_raw_console_write(buf);
273}
1/*
2 * xen console driver interface to hvc_console.c
3 *
4 * (c) 2007 Gerd Hoffmann <kraxel@suse.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/console.h>
22#include <linux/delay.h>
23#include <linux/err.h>
24#include <linux/irq.h>
25#include <linux/init.h>
26#include <linux/types.h>
27#include <linux/list.h>
28#include <linux/serial_core.h>
29
30#include <asm/io.h>
31#include <asm/xen/hypervisor.h>
32
33#include <xen/xen.h>
34#include <xen/interface/xen.h>
35#include <xen/hvm.h>
36#include <xen/grant_table.h>
37#include <xen/page.h>
38#include <xen/events.h>
39#include <xen/interface/io/console.h>
40#include <xen/interface/sched.h>
41#include <xen/hvc-console.h>
42#include <xen/xenbus.h>
43
44#include "hvc_console.h"
45
46#define HVC_COOKIE 0x58656e /* "Xen" in hex */
47
48struct xencons_info {
49 struct list_head list;
50 struct xenbus_device *xbdev;
51 struct xencons_interface *intf;
52 unsigned int evtchn;
53 struct hvc_struct *hvc;
54 int irq;
55 int vtermno;
56 grant_ref_t gntref;
57};
58
59static LIST_HEAD(xenconsoles);
60static DEFINE_SPINLOCK(xencons_lock);
61
62/* ------------------------------------------------------------------ */
63
64static struct xencons_info *vtermno_to_xencons(int vtermno)
65{
66 struct xencons_info *entry, *n, *ret = NULL;
67
68 if (list_empty(&xenconsoles))
69 return NULL;
70
71 list_for_each_entry_safe(entry, n, &xenconsoles, list) {
72 if (entry->vtermno == vtermno) {
73 ret = entry;
74 break;
75 }
76 }
77
78 return ret;
79}
80
81static inline int xenbus_devid_to_vtermno(int devid)
82{
83 return devid + HVC_COOKIE;
84}
85
86static inline void notify_daemon(struct xencons_info *cons)
87{
88 /* Use evtchn: this is called early, before irq is set up. */
89 notify_remote_via_evtchn(cons->evtchn);
90}
91
92static int __write_console(struct xencons_info *xencons,
93 const char *data, int len)
94{
95 XENCONS_RING_IDX cons, prod;
96 struct xencons_interface *intf = xencons->intf;
97 int sent = 0;
98
99 cons = intf->out_cons;
100 prod = intf->out_prod;
101 mb(); /* update queue values before going on */
102 BUG_ON((prod - cons) > sizeof(intf->out));
103
104 while ((sent < len) && ((prod - cons) < sizeof(intf->out)))
105 intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++];
106
107 wmb(); /* write ring before updating pointer */
108 intf->out_prod = prod;
109
110 if (sent)
111 notify_daemon(xencons);
112 return sent;
113}
114
115static int domU_write_console(uint32_t vtermno, const char *data, int len)
116{
117 int ret = len;
118 struct xencons_info *cons = vtermno_to_xencons(vtermno);
119 if (cons == NULL)
120 return -EINVAL;
121
122 /*
123 * Make sure the whole buffer is emitted, polling if
124 * necessary. We don't ever want to rely on the hvc daemon
125 * because the most interesting console output is when the
126 * kernel is crippled.
127 */
128 while (len) {
129 int sent = __write_console(cons, data, len);
130
131 data += sent;
132 len -= sent;
133
134 if (unlikely(len))
135 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
136 }
137
138 return ret;
139}
140
141static int domU_read_console(uint32_t vtermno, char *buf, int len)
142{
143 struct xencons_interface *intf;
144 XENCONS_RING_IDX cons, prod;
145 int recv = 0;
146 struct xencons_info *xencons = vtermno_to_xencons(vtermno);
147 if (xencons == NULL)
148 return -EINVAL;
149 intf = xencons->intf;
150
151 cons = intf->in_cons;
152 prod = intf->in_prod;
153 mb(); /* get pointers before reading ring */
154 BUG_ON((prod - cons) > sizeof(intf->in));
155
156 while (cons != prod && recv < len)
157 buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)];
158
159 mb(); /* read ring before consuming */
160 intf->in_cons = cons;
161
162 notify_daemon(xencons);
163 return recv;
164}
165
166static const struct hv_ops domU_hvc_ops = {
167 .get_chars = domU_read_console,
168 .put_chars = domU_write_console,
169 .notifier_add = notifier_add_irq,
170 .notifier_del = notifier_del_irq,
171 .notifier_hangup = notifier_hangup_irq,
172};
173
174static int dom0_read_console(uint32_t vtermno, char *buf, int len)
175{
176 return HYPERVISOR_console_io(CONSOLEIO_read, len, buf);
177}
178
179/*
180 * Either for a dom0 to write to the system console, or a domU with a
181 * debug version of Xen
182 */
183static int dom0_write_console(uint32_t vtermno, const char *str, int len)
184{
185 int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str);
186 if (rc < 0)
187 return rc;
188
189 return len;
190}
191
192static const struct hv_ops dom0_hvc_ops = {
193 .get_chars = dom0_read_console,
194 .put_chars = dom0_write_console,
195 .notifier_add = notifier_add_irq,
196 .notifier_del = notifier_del_irq,
197 .notifier_hangup = notifier_hangup_irq,
198};
199
200static int xen_hvm_console_init(void)
201{
202 int r;
203 uint64_t v = 0;
204 unsigned long gfn;
205 struct xencons_info *info;
206
207 if (!xen_hvm_domain())
208 return -ENODEV;
209
210 info = vtermno_to_xencons(HVC_COOKIE);
211 if (!info) {
212 info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
213 if (!info)
214 return -ENOMEM;
215 } else if (info->intf != NULL) {
216 /* already configured */
217 return 0;
218 }
219 /*
220 * If the toolstack (or the hypervisor) hasn't set these values, the
221 * default value is 0. Even though gfn = 0 and evtchn = 0 are
222 * theoretically correct values, in practice they never are and they
223 * mean that a legacy toolstack hasn't initialized the pv console correctly.
224 */
225 r = hvm_get_parameter(HVM_PARAM_CONSOLE_EVTCHN, &v);
226 if (r < 0 || v == 0)
227 goto err;
228 info->evtchn = v;
229 v = 0;
230 r = hvm_get_parameter(HVM_PARAM_CONSOLE_PFN, &v);
231 if (r < 0 || v == 0)
232 goto err;
233 gfn = v;
234 info->intf = xen_remap(gfn << XEN_PAGE_SHIFT, XEN_PAGE_SIZE);
235 if (info->intf == NULL)
236 goto err;
237 info->vtermno = HVC_COOKIE;
238
239 spin_lock(&xencons_lock);
240 list_add_tail(&info->list, &xenconsoles);
241 spin_unlock(&xencons_lock);
242
243 return 0;
244err:
245 kfree(info);
246 return -ENODEV;
247}
248
249static int xencons_info_pv_init(struct xencons_info *info, int vtermno)
250{
251 info->evtchn = xen_start_info->console.domU.evtchn;
252 /* GFN == MFN for PV guest */
253 info->intf = gfn_to_virt(xen_start_info->console.domU.mfn);
254 info->vtermno = vtermno;
255
256 list_add_tail(&info->list, &xenconsoles);
257
258 return 0;
259}
260
261static int xen_pv_console_init(void)
262{
263 struct xencons_info *info;
264
265 if (!xen_pv_domain())
266 return -ENODEV;
267
268 if (!xen_start_info->console.domU.evtchn)
269 return -ENODEV;
270
271 info = vtermno_to_xencons(HVC_COOKIE);
272 if (!info) {
273 info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
274 if (!info)
275 return -ENOMEM;
276 } else if (info->intf != NULL) {
277 /* already configured */
278 return 0;
279 }
280 spin_lock(&xencons_lock);
281 xencons_info_pv_init(info, HVC_COOKIE);
282 spin_unlock(&xencons_lock);
283
284 return 0;
285}
286
287static int xen_initial_domain_console_init(void)
288{
289 struct xencons_info *info;
290
291 if (!xen_initial_domain())
292 return -ENODEV;
293
294 info = vtermno_to_xencons(HVC_COOKIE);
295 if (!info) {
296 info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
297 if (!info)
298 return -ENOMEM;
299 }
300
301 info->irq = bind_virq_to_irq(VIRQ_CONSOLE, 0, false);
302 info->vtermno = HVC_COOKIE;
303
304 spin_lock(&xencons_lock);
305 list_add_tail(&info->list, &xenconsoles);
306 spin_unlock(&xencons_lock);
307
308 return 0;
309}
310
311static void xen_console_update_evtchn(struct xencons_info *info)
312{
313 if (xen_hvm_domain()) {
314 uint64_t v = 0;
315 int err;
316
317 err = hvm_get_parameter(HVM_PARAM_CONSOLE_EVTCHN, &v);
318 if (!err && v)
319 info->evtchn = v;
320 } else
321 info->evtchn = xen_start_info->console.domU.evtchn;
322}
323
324void xen_console_resume(void)
325{
326 struct xencons_info *info = vtermno_to_xencons(HVC_COOKIE);
327 if (info != NULL && info->irq) {
328 if (!xen_initial_domain())
329 xen_console_update_evtchn(info);
330 rebind_evtchn_irq(info->evtchn, info->irq);
331 }
332}
333
334#ifdef CONFIG_HVC_XEN_FRONTEND
335static void xencons_disconnect_backend(struct xencons_info *info)
336{
337 if (info->irq > 0)
338 unbind_from_irqhandler(info->irq, NULL);
339 info->irq = 0;
340 if (info->evtchn > 0)
341 xenbus_free_evtchn(info->xbdev, info->evtchn);
342 info->evtchn = 0;
343 if (info->gntref > 0)
344 gnttab_free_grant_references(info->gntref);
345 info->gntref = 0;
346 if (info->hvc != NULL)
347 hvc_remove(info->hvc);
348 info->hvc = NULL;
349}
350
351static void xencons_free(struct xencons_info *info)
352{
353 free_page((unsigned long)info->intf);
354 info->intf = NULL;
355 info->vtermno = 0;
356 kfree(info);
357}
358
359static int xen_console_remove(struct xencons_info *info)
360{
361 xencons_disconnect_backend(info);
362 spin_lock(&xencons_lock);
363 list_del(&info->list);
364 spin_unlock(&xencons_lock);
365 if (info->xbdev != NULL)
366 xencons_free(info);
367 else {
368 if (xen_hvm_domain())
369 iounmap(info->intf);
370 kfree(info);
371 }
372 return 0;
373}
374
375static int xencons_remove(struct xenbus_device *dev)
376{
377 return xen_console_remove(dev_get_drvdata(&dev->dev));
378}
379
380static int xencons_connect_backend(struct xenbus_device *dev,
381 struct xencons_info *info)
382{
383 int ret, evtchn, devid, ref, irq;
384 struct xenbus_transaction xbt;
385 grant_ref_t gref_head;
386
387 ret = xenbus_alloc_evtchn(dev, &evtchn);
388 if (ret)
389 return ret;
390 info->evtchn = evtchn;
391 irq = bind_evtchn_to_irq(evtchn);
392 if (irq < 0)
393 return irq;
394 info->irq = irq;
395 devid = dev->nodename[strlen(dev->nodename) - 1] - '0';
396 info->hvc = hvc_alloc(xenbus_devid_to_vtermno(devid),
397 irq, &domU_hvc_ops, 256);
398 if (IS_ERR(info->hvc))
399 return PTR_ERR(info->hvc);
400 ret = gnttab_alloc_grant_references(1, &gref_head);
401 if (ret < 0)
402 return ret;
403 info->gntref = gref_head;
404 ref = gnttab_claim_grant_reference(&gref_head);
405 if (ref < 0)
406 return ref;
407 gnttab_grant_foreign_access_ref(ref, info->xbdev->otherend_id,
408 virt_to_gfn(info->intf), 0);
409
410 again:
411 ret = xenbus_transaction_start(&xbt);
412 if (ret) {
413 xenbus_dev_fatal(dev, ret, "starting transaction");
414 return ret;
415 }
416 ret = xenbus_printf(xbt, dev->nodename, "ring-ref", "%d", ref);
417 if (ret)
418 goto error_xenbus;
419 ret = xenbus_printf(xbt, dev->nodename, "port", "%u",
420 evtchn);
421 if (ret)
422 goto error_xenbus;
423 ret = xenbus_transaction_end(xbt, 0);
424 if (ret) {
425 if (ret == -EAGAIN)
426 goto again;
427 xenbus_dev_fatal(dev, ret, "completing transaction");
428 return ret;
429 }
430
431 xenbus_switch_state(dev, XenbusStateInitialised);
432 return 0;
433
434 error_xenbus:
435 xenbus_transaction_end(xbt, 1);
436 xenbus_dev_fatal(dev, ret, "writing xenstore");
437 return ret;
438}
439
440static int xencons_probe(struct xenbus_device *dev,
441 const struct xenbus_device_id *id)
442{
443 int ret, devid;
444 struct xencons_info *info;
445
446 devid = dev->nodename[strlen(dev->nodename) - 1] - '0';
447 if (devid == 0)
448 return -ENODEV;
449
450 info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
451 if (!info)
452 return -ENOMEM;
453 dev_set_drvdata(&dev->dev, info);
454 info->xbdev = dev;
455 info->vtermno = xenbus_devid_to_vtermno(devid);
456 info->intf = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
457 if (!info->intf)
458 goto error_nomem;
459
460 ret = xencons_connect_backend(dev, info);
461 if (ret < 0)
462 goto error;
463 spin_lock(&xencons_lock);
464 list_add_tail(&info->list, &xenconsoles);
465 spin_unlock(&xencons_lock);
466
467 return 0;
468
469 error_nomem:
470 ret = -ENOMEM;
471 xenbus_dev_fatal(dev, ret, "allocating device memory");
472 error:
473 xencons_disconnect_backend(info);
474 xencons_free(info);
475 return ret;
476}
477
478static int xencons_resume(struct xenbus_device *dev)
479{
480 struct xencons_info *info = dev_get_drvdata(&dev->dev);
481
482 xencons_disconnect_backend(info);
483 memset(info->intf, 0, XEN_PAGE_SIZE);
484 return xencons_connect_backend(dev, info);
485}
486
487static void xencons_backend_changed(struct xenbus_device *dev,
488 enum xenbus_state backend_state)
489{
490 switch (backend_state) {
491 case XenbusStateReconfiguring:
492 case XenbusStateReconfigured:
493 case XenbusStateInitialising:
494 case XenbusStateInitialised:
495 case XenbusStateUnknown:
496 break;
497
498 case XenbusStateInitWait:
499 break;
500
501 case XenbusStateConnected:
502 xenbus_switch_state(dev, XenbusStateConnected);
503 break;
504
505 case XenbusStateClosed:
506 if (dev->state == XenbusStateClosed)
507 break;
508 /* Missed the backend's CLOSING state -- fallthrough */
509 case XenbusStateClosing:
510 xenbus_frontend_closed(dev);
511 break;
512 }
513}
514
515static const struct xenbus_device_id xencons_ids[] = {
516 { "console" },
517 { "" }
518};
519
520static struct xenbus_driver xencons_driver = {
521 .name = "xenconsole",
522 .ids = xencons_ids,
523 .probe = xencons_probe,
524 .remove = xencons_remove,
525 .resume = xencons_resume,
526 .otherend_changed = xencons_backend_changed,
527};
528#endif /* CONFIG_HVC_XEN_FRONTEND */
529
530static int __init xen_hvc_init(void)
531{
532 int r;
533 struct xencons_info *info;
534 const struct hv_ops *ops;
535
536 if (!xen_domain())
537 return -ENODEV;
538
539 if (xen_initial_domain()) {
540 ops = &dom0_hvc_ops;
541 r = xen_initial_domain_console_init();
542 if (r < 0)
543 return r;
544 info = vtermno_to_xencons(HVC_COOKIE);
545 } else {
546 ops = &domU_hvc_ops;
547 if (xen_hvm_domain())
548 r = xen_hvm_console_init();
549 else
550 r = xen_pv_console_init();
551 if (r < 0)
552 return r;
553
554 info = vtermno_to_xencons(HVC_COOKIE);
555 info->irq = bind_evtchn_to_irq(info->evtchn);
556 }
557 if (info->irq < 0)
558 info->irq = 0; /* NO_IRQ */
559 else
560 irq_set_noprobe(info->irq);
561
562 info->hvc = hvc_alloc(HVC_COOKIE, info->irq, ops, 256);
563 if (IS_ERR(info->hvc)) {
564 r = PTR_ERR(info->hvc);
565 spin_lock(&xencons_lock);
566 list_del(&info->list);
567 spin_unlock(&xencons_lock);
568 if (info->irq)
569 unbind_from_irqhandler(info->irq, NULL);
570 kfree(info);
571 return r;
572 }
573
574 r = 0;
575#ifdef CONFIG_HVC_XEN_FRONTEND
576 r = xenbus_register_frontend(&xencons_driver);
577#endif
578 return r;
579}
580device_initcall(xen_hvc_init);
581
582static int xen_cons_init(void)
583{
584 const struct hv_ops *ops;
585
586 if (!xen_domain())
587 return 0;
588
589 if (xen_initial_domain())
590 ops = &dom0_hvc_ops;
591 else {
592 int r;
593 ops = &domU_hvc_ops;
594
595 if (xen_hvm_domain())
596 r = xen_hvm_console_init();
597 else
598 r = xen_pv_console_init();
599 if (r < 0)
600 return r;
601 }
602
603 hvc_instantiate(HVC_COOKIE, 0, ops);
604 return 0;
605}
606console_initcall(xen_cons_init);
607
608#ifdef CONFIG_X86
609static void xen_hvm_early_write(uint32_t vtermno, const char *str, int len)
610{
611 if (xen_cpuid_base())
612 outsb(0xe9, str, len);
613}
614#else
615static void xen_hvm_early_write(uint32_t vtermno, const char *str, int len) { }
616#endif
617
618#ifdef CONFIG_EARLY_PRINTK
619static int __init xenboot_setup_console(struct console *console, char *string)
620{
621 static struct xencons_info xenboot;
622
623 if (xen_initial_domain())
624 return 0;
625 if (!xen_pv_domain())
626 return -ENODEV;
627
628 return xencons_info_pv_init(&xenboot, 0);
629}
630
631static void xenboot_write_console(struct console *console, const char *string,
632 unsigned len)
633{
634 unsigned int linelen, off = 0;
635 const char *pos;
636
637 if (!xen_pv_domain()) {
638 xen_hvm_early_write(0, string, len);
639 return;
640 }
641
642 dom0_write_console(0, string, len);
643
644 if (xen_initial_domain())
645 return;
646
647 domU_write_console(0, "(early) ", 8);
648 while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
649 linelen = pos-string+off;
650 if (off + linelen > len)
651 break;
652 domU_write_console(0, string+off, linelen);
653 domU_write_console(0, "\r\n", 2);
654 off += linelen + 1;
655 }
656 if (off < len)
657 domU_write_console(0, string+off, len-off);
658}
659
660struct console xenboot_console = {
661 .name = "xenboot",
662 .write = xenboot_write_console,
663 .setup = xenboot_setup_console,
664 .flags = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
665 .index = -1,
666};
667#endif /* CONFIG_EARLY_PRINTK */
668
669void xen_raw_console_write(const char *str)
670{
671 ssize_t len = strlen(str);
672 int rc = 0;
673
674 if (xen_domain()) {
675 rc = dom0_write_console(0, str, len);
676 if (rc != -ENOSYS || !xen_hvm_domain())
677 return;
678 }
679 xen_hvm_early_write(0, str, len);
680}
681
682void xen_raw_printk(const char *fmt, ...)
683{
684 static char buf[512];
685 va_list ap;
686
687 va_start(ap, fmt);
688 vsnprintf(buf, sizeof(buf), fmt, ap);
689 va_end(ap);
690
691 xen_raw_console_write(buf);
692}
693
694static void xenboot_earlycon_write(struct console *console,
695 const char *string,
696 unsigned len)
697{
698 dom0_write_console(0, string, len);
699}
700
701static int __init xenboot_earlycon_setup(struct earlycon_device *device,
702 const char *opt)
703{
704 device->con->write = xenboot_earlycon_write;
705 return 0;
706}
707EARLYCON_DECLARE(xenboot, xenboot_earlycon_setup);