m68knommu: remove local gettimeofday code
[wrt350n-kernel.git] / arch / um / drivers / mconsole_kern.c
blob0f3c7d14a6e32977d1731a7c46daa51e08182534
1 /*
2 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org)
3 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 * Licensed under the GPL
5 */
7 #include "linux/console.h"
8 #include "linux/ctype.h"
9 #include "linux/interrupt.h"
10 #include "linux/list.h"
11 #include "linux/mm.h"
12 #include "linux/module.h"
13 #include "linux/notifier.h"
14 #include "linux/reboot.h"
15 #include "linux/proc_fs.h"
16 #include "linux/slab.h"
17 #include "linux/syscalls.h"
18 #include "linux/utsname.h"
19 #include "linux/workqueue.h"
20 #include "asm/uaccess.h"
21 #include "init.h"
22 #include "irq_kern.h"
23 #include "irq_user.h"
24 #include "kern_util.h"
25 #include "mconsole.h"
26 #include "mconsole_kern.h"
27 #include "os.h"
29 static int do_unlink_socket(struct notifier_block *notifier,
30 unsigned long what, void *data)
32 return mconsole_unlink_socket();
36 static struct notifier_block reboot_notifier = {
37 .notifier_call = do_unlink_socket,
38 .priority = 0,
41 /* Safe without explicit locking for now. Tasklets provide their own
42 * locking, and the interrupt handler is safe because it can't interrupt
43 * itself and it can only happen on CPU 0.
46 static LIST_HEAD(mc_requests);
48 static void mc_work_proc(struct work_struct *unused)
50 struct mconsole_entry *req;
51 unsigned long flags;
53 while (!list_empty(&mc_requests)) {
54 local_irq_save(flags);
55 req = list_entry(mc_requests.next, struct mconsole_entry, list);
56 list_del(&req->list);
57 local_irq_restore(flags);
58 req->request.cmd->handler(&req->request);
59 kfree(req);
63 static DECLARE_WORK(mconsole_work, mc_work_proc);
65 static irqreturn_t mconsole_interrupt(int irq, void *dev_id)
67 /* long to avoid size mismatch warnings from gcc */
68 long fd;
69 struct mconsole_entry *new;
70 static struct mc_request req; /* that's OK */
72 fd = (long) dev_id;
73 while (mconsole_get_request(fd, &req)) {
74 if (req.cmd->context == MCONSOLE_INTR)
75 (*req.cmd->handler)(&req);
76 else {
77 new = kmalloc(sizeof(*new), GFP_NOWAIT);
78 if (new == NULL)
79 mconsole_reply(&req, "Out of memory", 1, 0);
80 else {
81 new->request = req;
82 new->request.regs = get_irq_regs()->regs;
83 list_add(&new->list, &mc_requests);
87 if (!list_empty(&mc_requests))
88 schedule_work(&mconsole_work);
89 reactivate_fd(fd, MCONSOLE_IRQ);
90 return IRQ_HANDLED;
93 void mconsole_version(struct mc_request *req)
95 char version[256];
97 sprintf(version, "%s %s %s %s %s", utsname()->sysname,
98 utsname()->nodename, utsname()->release, utsname()->version,
99 utsname()->machine);
100 mconsole_reply(req, version, 0, 0);
103 void mconsole_log(struct mc_request *req)
105 int len;
106 char *ptr = req->request.data;
108 ptr += strlen("log ");
110 len = req->len - (ptr - req->request.data);
111 printk(KERN_WARNING "%.*s", len, ptr);
112 mconsole_reply(req, "", 0, 0);
115 /* This is a more convoluted version of mconsole_proc, which has some stability
116 * problems; however, we need it fixed, because it is expected that UML users
117 * mount HPPFS instead of procfs on /proc. And we want mconsole_proc to still
118 * show the real procfs content, not the ones from hppfs.*/
119 #if 0
120 void mconsole_proc(struct mc_request *req)
122 struct nameidata nd;
123 struct file_system_type *proc;
124 struct super_block *super;
125 struct file *file;
126 int n, err;
127 char *ptr = req->request.data, *buf;
129 ptr += strlen("proc");
130 while (isspace(*ptr)) ptr++;
132 proc = get_fs_type("proc");
133 if (proc == NULL) {
134 mconsole_reply(req, "procfs not registered", 1, 0);
135 goto out;
138 super = (*proc->get_sb)(proc, 0, NULL, NULL);
139 put_filesystem(proc);
140 if (super == NULL) {
141 mconsole_reply(req, "Failed to get procfs superblock", 1, 0);
142 goto out;
144 up_write(&super->s_umount);
146 nd.dentry = super->s_root;
147 nd.mnt = NULL;
148 nd.flags = O_RDONLY + 1;
149 nd.last_type = LAST_ROOT;
151 /* START: it was experienced that the stability problems are closed
152 * if commenting out these two calls + the below read cycle. To
153 * make UML crash again, it was enough to readd either one.*/
154 err = link_path_walk(ptr, &nd);
155 if (err) {
156 mconsole_reply(req, "Failed to look up file", 1, 0);
157 goto out_kill;
160 file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
161 if (IS_ERR(file)) {
162 mconsole_reply(req, "Failed to open file", 1, 0);
163 goto out_kill;
165 /*END*/
167 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
168 if (buf == NULL) {
169 mconsole_reply(req, "Failed to allocate buffer", 1, 0);
170 goto out_fput;
173 if ((file->f_op != NULL) && (file->f_op->read != NULL)) {
174 do {
175 n = (*file->f_op->read)(file, buf, PAGE_SIZE - 1,
176 &file->f_pos);
177 if (n >= 0) {
178 buf[n] = '\0';
179 mconsole_reply(req, buf, 0, (n > 0));
181 else {
182 mconsole_reply(req, "Read of file failed",
183 1, 0);
184 goto out_free;
186 } while (n > 0);
188 else mconsole_reply(req, "", 0, 0);
190 out_free:
191 kfree(buf);
192 out_fput:
193 fput(file);
194 out_kill:
195 deactivate_super(super);
196 out: ;
198 #endif
200 void mconsole_proc(struct mc_request *req)
202 char path[64];
203 char *buf;
204 int len;
205 int fd;
206 int first_chunk = 1;
207 char *ptr = req->request.data;
209 ptr += strlen("proc");
210 while (isspace(*ptr))
211 ptr++;
212 snprintf(path, sizeof(path), "/proc/%s", ptr);
214 fd = sys_open(path, 0, 0);
215 if (fd < 0) {
216 mconsole_reply(req, "Failed to open file", 1, 0);
217 printk(KERN_ERR "open %s: %d\n",path,fd);
218 goto out;
221 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
222 if (buf == NULL) {
223 mconsole_reply(req, "Failed to allocate buffer", 1, 0);
224 goto out_close;
227 for (;;) {
228 len = sys_read(fd, buf, PAGE_SIZE-1);
229 if (len < 0) {
230 mconsole_reply(req, "Read of file failed", 1, 0);
231 goto out_free;
233 /* Begin the file content on his own line. */
234 if (first_chunk) {
235 mconsole_reply(req, "\n", 0, 1);
236 first_chunk = 0;
238 if (len == PAGE_SIZE-1) {
239 buf[len] = '\0';
240 mconsole_reply(req, buf, 0, 1);
241 } else {
242 buf[len] = '\0';
243 mconsole_reply(req, buf, 0, 0);
244 break;
248 out_free:
249 kfree(buf);
250 out_close:
251 sys_close(fd);
252 out:
253 /* nothing */;
256 #define UML_MCONSOLE_HELPTEXT \
257 "Commands: \n\
258 version - Get kernel version \n\
259 help - Print this message \n\
260 halt - Halt UML \n\
261 reboot - Reboot UML \n\
262 config <dev>=<config> - Add a new device to UML; \n\
263 same syntax as command line \n\
264 config <dev> - Query the configuration of a device \n\
265 remove <dev> - Remove a device from UML \n\
266 sysrq <letter> - Performs the SysRq action controlled by the letter \n\
267 cad - invoke the Ctrl-Alt-Del handler \n\
268 stop - pause the UML; it will do nothing until it receives a 'go' \n\
269 go - continue the UML after a 'stop' \n\
270 log <string> - make UML enter <string> into the kernel log\n\
271 proc <file> - returns the contents of the UML's /proc/<file>\n\
272 stack <pid> - returns the stack of the specified pid\n\
275 void mconsole_help(struct mc_request *req)
277 mconsole_reply(req, UML_MCONSOLE_HELPTEXT, 0, 0);
280 void mconsole_halt(struct mc_request *req)
282 mconsole_reply(req, "", 0, 0);
283 machine_halt();
286 void mconsole_reboot(struct mc_request *req)
288 mconsole_reply(req, "", 0, 0);
289 machine_restart(NULL);
292 void mconsole_cad(struct mc_request *req)
294 mconsole_reply(req, "", 0, 0);
295 ctrl_alt_del();
298 void mconsole_go(struct mc_request *req)
300 mconsole_reply(req, "Not stopped", 1, 0);
303 void mconsole_stop(struct mc_request *req)
305 deactivate_fd(req->originating_fd, MCONSOLE_IRQ);
306 os_set_fd_block(req->originating_fd, 1);
307 mconsole_reply(req, "stopped", 0, 0);
308 while (mconsole_get_request(req->originating_fd, req)) {
309 if (req->cmd->handler == mconsole_go)
310 break;
311 if (req->cmd->handler == mconsole_stop) {
312 mconsole_reply(req, "Already stopped", 1, 0);
313 continue;
315 if (req->cmd->handler == mconsole_sysrq) {
316 struct pt_regs *old_regs;
317 old_regs = set_irq_regs((struct pt_regs *)&req->regs);
318 mconsole_sysrq(req);
319 set_irq_regs(old_regs);
320 continue;
322 (*req->cmd->handler)(req);
324 os_set_fd_block(req->originating_fd, 0);
325 reactivate_fd(req->originating_fd, MCONSOLE_IRQ);
326 mconsole_reply(req, "", 0, 0);
329 static DEFINE_SPINLOCK(mc_devices_lock);
330 static LIST_HEAD(mconsole_devices);
332 void mconsole_register_dev(struct mc_device *new)
334 spin_lock(&mc_devices_lock);
335 BUG_ON(!list_empty(&new->list));
336 list_add(&new->list, &mconsole_devices);
337 spin_unlock(&mc_devices_lock);
340 static struct mc_device *mconsole_find_dev(char *name)
342 struct list_head *ele;
343 struct mc_device *dev;
345 list_for_each(ele, &mconsole_devices) {
346 dev = list_entry(ele, struct mc_device, list);
347 if (!strncmp(name, dev->name, strlen(dev->name)))
348 return dev;
350 return NULL;
353 #define UNPLUGGED_PER_PAGE \
354 ((PAGE_SIZE - sizeof(struct list_head)) / sizeof(unsigned long))
356 struct unplugged_pages {
357 struct list_head list;
358 void *pages[UNPLUGGED_PER_PAGE];
361 static DECLARE_MUTEX(plug_mem_mutex);
362 static unsigned long long unplugged_pages_count = 0;
363 static LIST_HEAD(unplugged_pages);
364 static int unplug_index = UNPLUGGED_PER_PAGE;
366 static int mem_config(char *str, char **error_out)
368 unsigned long long diff;
369 int err = -EINVAL, i, add;
370 char *ret;
372 if (str[0] != '=') {
373 *error_out = "Expected '=' after 'mem'";
374 goto out;
377 str++;
378 if (str[0] == '-')
379 add = 0;
380 else if (str[0] == '+') {
381 add = 1;
383 else {
384 *error_out = "Expected increment to start with '-' or '+'";
385 goto out;
388 str++;
389 diff = memparse(str, &ret);
390 if (*ret != '\0') {
391 *error_out = "Failed to parse memory increment";
392 goto out;
395 diff /= PAGE_SIZE;
397 down(&plug_mem_mutex);
398 for (i = 0; i < diff; i++) {
399 struct unplugged_pages *unplugged;
400 void *addr;
402 if (add) {
403 if (list_empty(&unplugged_pages))
404 break;
406 unplugged = list_entry(unplugged_pages.next,
407 struct unplugged_pages, list);
408 if (unplug_index > 0)
409 addr = unplugged->pages[--unplug_index];
410 else {
411 list_del(&unplugged->list);
412 addr = unplugged;
413 unplug_index = UNPLUGGED_PER_PAGE;
416 free_page((unsigned long) addr);
417 unplugged_pages_count--;
419 else {
420 struct page *page;
422 page = alloc_page(GFP_ATOMIC);
423 if (page == NULL)
424 break;
426 unplugged = page_address(page);
427 if (unplug_index == UNPLUGGED_PER_PAGE) {
428 list_add(&unplugged->list, &unplugged_pages);
429 unplug_index = 0;
431 else {
432 struct list_head *entry = unplugged_pages.next;
433 addr = unplugged;
435 unplugged = list_entry(entry,
436 struct unplugged_pages,
437 list);
438 err = os_drop_memory(addr, PAGE_SIZE);
439 if (err) {
440 printk(KERN_ERR "Failed to release "
441 "memory - errno = %d\n", err);
442 *error_out = "Failed to release memory";
443 goto out_unlock;
445 unplugged->pages[unplug_index++] = addr;
448 unplugged_pages_count++;
452 err = 0;
453 out_unlock:
454 up(&plug_mem_mutex);
455 out:
456 return err;
459 static int mem_get_config(char *name, char *str, int size, char **error_out)
461 char buf[sizeof("18446744073709551615")];
462 int len = 0;
464 sprintf(buf, "%ld", uml_physmem);
465 CONFIG_CHUNK(str, size, len, buf, 1);
467 return len;
470 static int mem_id(char **str, int *start_out, int *end_out)
472 *start_out = 0;
473 *end_out = 0;
475 return 0;
478 static int mem_remove(int n, char **error_out)
480 *error_out = "Memory doesn't support the remove operation";
481 return -EBUSY;
484 static struct mc_device mem_mc = {
485 .list = LIST_HEAD_INIT(mem_mc.list),
486 .name = "mem",
487 .config = mem_config,
488 .get_config = mem_get_config,
489 .id = mem_id,
490 .remove = mem_remove,
493 static int __init mem_mc_init(void)
495 if (can_drop_memory())
496 mconsole_register_dev(&mem_mc);
497 else printk(KERN_ERR "Can't release memory to the host - memory "
498 "hotplug won't be supported\n");
499 return 0;
502 __initcall(mem_mc_init);
504 #define CONFIG_BUF_SIZE 64
506 static void mconsole_get_config(int (*get_config)(char *, char *, int,
507 char **),
508 struct mc_request *req, char *name)
510 char default_buf[CONFIG_BUF_SIZE], *error, *buf;
511 int n, size;
513 if (get_config == NULL) {
514 mconsole_reply(req, "No get_config routine defined", 1, 0);
515 return;
518 error = NULL;
519 size = ARRAY_SIZE(default_buf);
520 buf = default_buf;
522 while (1) {
523 n = (*get_config)(name, buf, size, &error);
524 if (error != NULL) {
525 mconsole_reply(req, error, 1, 0);
526 goto out;
529 if (n <= size) {
530 mconsole_reply(req, buf, 0, 0);
531 goto out;
534 if (buf != default_buf)
535 kfree(buf);
537 size = n;
538 buf = kmalloc(size, GFP_KERNEL);
539 if (buf == NULL) {
540 mconsole_reply(req, "Failed to allocate buffer", 1, 0);
541 return;
544 out:
545 if (buf != default_buf)
546 kfree(buf);
549 void mconsole_config(struct mc_request *req)
551 struct mc_device *dev;
552 char *ptr = req->request.data, *name, *error_string = "";
553 int err;
555 ptr += strlen("config");
556 while (isspace(*ptr))
557 ptr++;
558 dev = mconsole_find_dev(ptr);
559 if (dev == NULL) {
560 mconsole_reply(req, "Bad configuration option", 1, 0);
561 return;
564 name = &ptr[strlen(dev->name)];
565 ptr = name;
566 while ((*ptr != '=') && (*ptr != '\0'))
567 ptr++;
569 if (*ptr == '=') {
570 err = (*dev->config)(name, &error_string);
571 mconsole_reply(req, error_string, err, 0);
573 else mconsole_get_config(dev->get_config, req, name);
576 void mconsole_remove(struct mc_request *req)
578 struct mc_device *dev;
579 char *ptr = req->request.data, *err_msg = "";
580 char error[256];
581 int err, start, end, n;
583 ptr += strlen("remove");
584 while (isspace(*ptr)) ptr++;
585 dev = mconsole_find_dev(ptr);
586 if (dev == NULL) {
587 mconsole_reply(req, "Bad remove option", 1, 0);
588 return;
591 ptr = &ptr[strlen(dev->name)];
593 err = 1;
594 n = (*dev->id)(&ptr, &start, &end);
595 if (n < 0) {
596 err_msg = "Couldn't parse device number";
597 goto out;
599 else if ((n < start) || (n > end)) {
600 sprintf(error, "Invalid device number - must be between "
601 "%d and %d", start, end);
602 err_msg = error;
603 goto out;
606 err_msg = NULL;
607 err = (*dev->remove)(n, &err_msg);
608 switch(err) {
609 case 0:
610 err_msg = "";
611 break;
612 case -ENODEV:
613 if (err_msg == NULL)
614 err_msg = "Device doesn't exist";
615 break;
616 case -EBUSY:
617 if (err_msg == NULL)
618 err_msg = "Device is currently open";
619 break;
620 default:
621 break;
623 out:
624 mconsole_reply(req, err_msg, err, 0);
627 struct mconsole_output {
628 struct list_head list;
629 struct mc_request *req;
632 static DEFINE_SPINLOCK(client_lock);
633 static LIST_HEAD(clients);
634 static char console_buf[MCONSOLE_MAX_DATA];
636 static void console_write(struct console *console, const char *string,
637 unsigned int len)
639 struct list_head *ele;
640 int n;
642 if (list_empty(&clients))
643 return;
645 while (len > 0) {
646 n = min((size_t) len, ARRAY_SIZE(console_buf));
647 strncpy(console_buf, string, n);
648 string += n;
649 len -= n;
651 list_for_each(ele, &clients) {
652 struct mconsole_output *entry;
654 entry = list_entry(ele, struct mconsole_output, list);
655 mconsole_reply_len(entry->req, console_buf, n, 0, 1);
660 static struct console mc_console = { .name = "mc",
661 .write = console_write,
662 .flags = CON_ENABLED,
663 .index = -1 };
665 static int mc_add_console(void)
667 register_console(&mc_console);
668 return 0;
671 late_initcall(mc_add_console);
673 static void with_console(struct mc_request *req, void (*proc)(void *),
674 void *arg)
676 struct mconsole_output entry;
677 unsigned long flags;
679 entry.req = req;
680 spin_lock_irqsave(&client_lock, flags);
681 list_add(&entry.list, &clients);
682 spin_unlock_irqrestore(&client_lock, flags);
684 (*proc)(arg);
686 mconsole_reply_len(req, "", 0, 0, 0);
688 spin_lock_irqsave(&client_lock, flags);
689 list_del(&entry.list);
690 spin_unlock_irqrestore(&client_lock, flags);
693 #ifdef CONFIG_MAGIC_SYSRQ
695 #include <linux/sysrq.h>
697 static void sysrq_proc(void *arg)
699 char *op = arg;
700 handle_sysrq(*op, NULL);
703 void mconsole_sysrq(struct mc_request *req)
705 char *ptr = req->request.data;
707 ptr += strlen("sysrq");
708 while (isspace(*ptr)) ptr++;
711 * With 'b', the system will shut down without a chance to reply,
712 * so in this case, we reply first.
714 if (*ptr == 'b')
715 mconsole_reply(req, "", 0, 0);
717 with_console(req, sysrq_proc, ptr);
719 #else
720 void mconsole_sysrq(struct mc_request *req)
722 mconsole_reply(req, "Sysrq not compiled in", 1, 0);
724 #endif
726 static void stack_proc(void *arg)
728 struct task_struct *from = current, *to = arg;
730 to->thread.saved_task = from;
731 switch_to(from, to, from);
735 * Mconsole stack trace
736 * Added by Allan Graves, Jeff Dike
737 * Dumps a stacks registers to the linux console.
738 * Usage stack <pid>.
740 void mconsole_stack(struct mc_request *req)
742 char *ptr = req->request.data;
743 int pid_requested= -1;
744 struct task_struct *from = NULL;
745 struct task_struct *to = NULL;
748 * Would be nice:
749 * 1) Send showregs output to mconsole.
750 * 2) Add a way to stack dump all pids.
753 ptr += strlen("stack");
754 while (isspace(*ptr))
755 ptr++;
758 * Should really check for multiple pids or reject bad args here
760 /* What do the arguments in mconsole_reply mean? */
761 if (sscanf(ptr, "%d", &pid_requested) == 0) {
762 mconsole_reply(req, "Please specify a pid", 1, 0);
763 return;
766 from = current;
768 to = find_task_by_pid(pid_requested);
769 if ((to == NULL) || (pid_requested == 0)) {
770 mconsole_reply(req, "Couldn't find that pid", 1, 0);
771 return;
773 with_console(req, stack_proc, to);
777 * Changed by mconsole_setup, which is __setup, and called before SMP is
778 * active.
780 static char *notify_socket = NULL;
782 static int __init mconsole_init(void)
784 /* long to avoid size mismatch warnings from gcc */
785 long sock;
786 int err;
787 char file[256];
789 if (umid_file_name("mconsole", file, sizeof(file)))
790 return -1;
791 snprintf(mconsole_socket_name, sizeof(file), "%s", file);
793 sock = os_create_unix_socket(file, sizeof(file), 1);
794 if (sock < 0) {
795 printk(KERN_ERR "Failed to initialize management console\n");
796 return 1;
799 register_reboot_notifier(&reboot_notifier);
801 err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt,
802 IRQF_DISABLED | IRQF_SHARED | IRQF_SAMPLE_RANDOM,
803 "mconsole", (void *)sock);
804 if (err) {
805 printk(KERN_ERR "Failed to get IRQ for management console\n");
806 return 1;
809 if (notify_socket != NULL) {
810 notify_socket = kstrdup(notify_socket, GFP_KERNEL);
811 if (notify_socket != NULL)
812 mconsole_notify(notify_socket, MCONSOLE_SOCKET,
813 mconsole_socket_name,
814 strlen(mconsole_socket_name) + 1);
815 else printk(KERN_ERR "mconsole_setup failed to strdup "
816 "string\n");
819 printk(KERN_INFO "mconsole (version %d) initialized on %s\n",
820 MCONSOLE_VERSION, mconsole_socket_name);
821 return 0;
824 __initcall(mconsole_init);
826 static int write_proc_mconsole(struct file *file, const char __user *buffer,
827 unsigned long count, void *data)
829 char *buf;
831 buf = kmalloc(count + 1, GFP_KERNEL);
832 if (buf == NULL)
833 return -ENOMEM;
835 if (copy_from_user(buf, buffer, count)) {
836 count = -EFAULT;
837 goto out;
840 buf[count] = '\0';
842 mconsole_notify(notify_socket, MCONSOLE_USER_NOTIFY, buf, count);
843 out:
844 kfree(buf);
845 return count;
848 static int create_proc_mconsole(void)
850 struct proc_dir_entry *ent;
852 if (notify_socket == NULL)
853 return 0;
855 ent = create_proc_entry("mconsole", S_IFREG | 0200, NULL);
856 if (ent == NULL) {
857 printk(KERN_INFO "create_proc_mconsole : create_proc_entry "
858 "failed\n");
859 return 0;
862 ent->read_proc = NULL;
863 ent->write_proc = write_proc_mconsole;
864 return 0;
867 static DEFINE_SPINLOCK(notify_spinlock);
869 void lock_notify(void)
871 spin_lock(&notify_spinlock);
874 void unlock_notify(void)
876 spin_unlock(&notify_spinlock);
879 __initcall(create_proc_mconsole);
881 #define NOTIFY "notify:"
883 static int mconsole_setup(char *str)
885 if (!strncmp(str, NOTIFY, strlen(NOTIFY))) {
886 str += strlen(NOTIFY);
887 notify_socket = str;
889 else printk(KERN_ERR "mconsole_setup : Unknown option - '%s'\n", str);
890 return 1;
893 __setup("mconsole=", mconsole_setup);
895 __uml_help(mconsole_setup,
896 "mconsole=notify:<socket>\n"
897 " Requests that the mconsole driver send a message to the named Unix\n"
898 " socket containing the name of the mconsole socket. This also serves\n"
899 " to notify outside processes when UML has booted far enough to respond\n"
900 " to mconsole requests.\n\n"
903 static int notify_panic(struct notifier_block *self, unsigned long unused1,
904 void *ptr)
906 char *message = ptr;
908 if (notify_socket == NULL)
909 return 0;
911 mconsole_notify(notify_socket, MCONSOLE_PANIC, message,
912 strlen(message) + 1);
913 return 0;
916 static struct notifier_block panic_exit_notifier = {
917 .notifier_call = notify_panic,
918 .next = NULL,
919 .priority = 1
922 static int add_notifier(void)
924 atomic_notifier_chain_register(&panic_notifier_list,
925 &panic_exit_notifier);
926 return 0;
929 __initcall(add_notifier);
931 char *mconsole_notify_socket(void)
933 return notify_socket;
936 EXPORT_SYMBOL(mconsole_notify_socket);