2 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org)
3 * Copyright (C) 2001 - 2003 Jeff Dike (jdike@addtoit.com)
4 * Licensed under the GPL
7 #include "linux/kernel.h"
8 #include "linux/slab.h"
9 #include "linux/init.h"
10 #include "linux/notifier.h"
11 #include "linux/reboot.h"
12 #include "linux/utsname.h"
13 #include "linux/ctype.h"
14 #include "linux/interrupt.h"
15 #include "linux/sysrq.h"
16 #include "linux/workqueue.h"
17 #include "linux/module.h"
18 #include "linux/file.h"
20 #include "linux/namei.h"
21 #include "linux/proc_fs.h"
22 #include "linux/syscalls.h"
24 #include "asm/uaccess.h"
25 #include "user_util.h"
26 #include "kern_util.h"
29 #include "mconsole_kern.h"
36 static int do_unlink_socket(struct notifier_block *notifier,
37 unsigned long what, void *data)
39 return(mconsole_unlink_socket());
43 static struct notifier_block reboot_notifier = {
44 .notifier_call = do_unlink_socket,
48 /* Safe without explicit locking for now. Tasklets provide their own
49 * locking, and the interrupt handler is safe because it can't interrupt
50 * itself and it can only happen on CPU 0.
53 LIST_HEAD(mc_requests);
55 static void mc_work_proc(void *unused)
57 struct mconsole_entry *req;
60 while(!list_empty(&mc_requests)){
61 local_save_flags(flags);
62 req = list_entry(mc_requests.next, struct mconsole_entry,
65 local_irq_restore(flags);
66 req->request.cmd->handler(&req->request);
71 DECLARE_WORK(mconsole_work, mc_work_proc, NULL);
73 static irqreturn_t mconsole_interrupt(int irq, void *dev_id,
77 struct mconsole_entry *new;
78 struct mc_request req;
81 while (mconsole_get_request(fd, &req)){
82 if(req.cmd->context == MCONSOLE_INTR)
83 (*req.cmd->handler)(&req);
85 new = kmalloc(sizeof(*new), GFP_ATOMIC);
87 mconsole_reply(&req, "Out of memory", 1, 0);
90 list_add(&new->list, &mc_requests);
94 if(!list_empty(&mc_requests))
95 schedule_work(&mconsole_work);
96 reactivate_fd(fd, MCONSOLE_IRQ);
100 void mconsole_version(struct mc_request *req)
104 sprintf(version, "%s %s %s %s %s", system_utsname.sysname,
105 system_utsname.nodename, system_utsname.release,
106 system_utsname.version, system_utsname.machine);
107 mconsole_reply(req, version, 0, 0);
110 void mconsole_log(struct mc_request *req)
113 char *ptr = req->request.data;
115 ptr += strlen("log ");
117 len = req->len - (ptr - req->request.data);
118 printk("%.*s", len, ptr);
119 mconsole_reply(req, "", 0, 0);
122 /* This is a more convoluted version of mconsole_proc, which has some stability
123 * problems; however, we need it fixed, because it is expected that UML users
124 * mount HPPFS instead of procfs on /proc. And we want mconsole_proc to still
125 * show the real procfs content, not the ones from hppfs.*/
127 void mconsole_proc(struct mc_request *req)
130 struct file_system_type *proc;
131 struct super_block *super;
134 char *ptr = req->request.data, *buf;
136 ptr += strlen("proc");
137 while(isspace(*ptr)) ptr++;
139 proc = get_fs_type("proc");
141 mconsole_reply(req, "procfs not registered", 1, 0);
145 super = (*proc->get_sb)(proc, 0, NULL, NULL);
146 put_filesystem(proc);
148 mconsole_reply(req, "Failed to get procfs superblock", 1, 0);
151 up_write(&super->s_umount);
153 nd.dentry = super->s_root;
155 nd.flags = O_RDONLY + 1;
156 nd.last_type = LAST_ROOT;
158 /* START: it was experienced that the stability problems are closed
159 * if commenting out these two calls + the below read cycle. To
160 * make UML crash again, it was enough to readd either one.*/
161 err = link_path_walk(ptr, &nd);
163 mconsole_reply(req, "Failed to look up file", 1, 0);
167 file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
169 mconsole_reply(req, "Failed to open file", 1, 0);
174 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
176 mconsole_reply(req, "Failed to allocate buffer", 1, 0);
180 if((file->f_op != NULL) && (file->f_op->read != NULL)){
182 n = (*file->f_op->read)(file, buf, PAGE_SIZE - 1,
186 mconsole_reply(req, buf, 0, (n > 0));
189 mconsole_reply(req, "Read of file failed",
195 else mconsole_reply(req, "", 0, 0);
202 deactivate_super(super);
207 void mconsole_proc(struct mc_request *req)
214 char *ptr = req->request.data;
216 ptr += strlen("proc");
217 while(isspace(*ptr)) ptr++;
218 snprintf(path, sizeof(path), "/proc/%s", ptr);
220 fd = sys_open(path, 0, 0);
222 mconsole_reply(req, "Failed to open file", 1, 0);
223 printk("open %s: %d\n",path,fd);
227 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
229 mconsole_reply(req, "Failed to allocate buffer", 1, 0);
234 len = sys_read(fd, buf, PAGE_SIZE-1);
236 mconsole_reply(req, "Read of file failed", 1, 0);
239 /*Begin the file content on his own line.*/
241 mconsole_reply(req, "\n", 0, 1);
244 if (len == PAGE_SIZE-1) {
246 mconsole_reply(req, buf, 0, 1);
249 mconsole_reply(req, buf, 0, 0);
262 #define UML_MCONSOLE_HELPTEXT \
264 version - Get kernel version \n\
265 help - Print this message \n\
267 reboot - Reboot UML \n\
268 config <dev>=<config> - Add a new device to UML; \n\
269 same syntax as command line \n\
270 config <dev> - Query the configuration of a device \n\
271 remove <dev> - Remove a device from UML \n\
272 sysrq <letter> - Performs the SysRq action controlled by the letter \n\
273 cad - invoke the Ctl-Alt-Del handler \n\
274 stop - pause the UML; it will do nothing until it receives a 'go' \n\
275 go - continue the UML after a 'stop' \n\
276 log <string> - make UML enter <string> into the kernel log\n\
277 proc <file> - returns the contents of the UML's /proc/<file>\n\
280 void mconsole_help(struct mc_request *req)
282 mconsole_reply(req, UML_MCONSOLE_HELPTEXT, 0, 0);
285 void mconsole_halt(struct mc_request *req)
287 mconsole_reply(req, "", 0, 0);
291 void mconsole_reboot(struct mc_request *req)
293 mconsole_reply(req, "", 0, 0);
294 machine_restart(NULL);
297 extern void ctrl_alt_del(void);
299 void mconsole_cad(struct mc_request *req)
301 mconsole_reply(req, "", 0, 0);
305 void mconsole_go(struct mc_request *req)
307 mconsole_reply(req, "Not stopped", 1, 0);
310 void mconsole_stop(struct mc_request *req)
312 deactivate_fd(req->originating_fd, MCONSOLE_IRQ);
313 os_set_fd_block(req->originating_fd, 1);
314 mconsole_reply(req, "", 0, 0);
315 while(mconsole_get_request(req->originating_fd, req)){
316 if(req->cmd->handler == mconsole_go) break;
317 (*req->cmd->handler)(req);
319 os_set_fd_block(req->originating_fd, 0);
320 reactivate_fd(req->originating_fd, MCONSOLE_IRQ);
321 mconsole_reply(req, "", 0, 0);
324 /* This list is populated by __initcall routines. */
326 LIST_HEAD(mconsole_devices);
328 void mconsole_register_dev(struct mc_device *new)
330 list_add(&new->list, &mconsole_devices);
333 static struct mc_device *mconsole_find_dev(char *name)
335 struct list_head *ele;
336 struct mc_device *dev;
338 list_for_each(ele, &mconsole_devices){
339 dev = list_entry(ele, struct mc_device, list);
340 if(!strncmp(name, dev->name, strlen(dev->name)))
346 #define CONFIG_BUF_SIZE 64
348 static void mconsole_get_config(int (*get_config)(char *, char *, int,
350 struct mc_request *req, char *name)
352 char default_buf[CONFIG_BUF_SIZE], *error, *buf;
355 if(get_config == NULL){
356 mconsole_reply(req, "No get_config routine defined", 1, 0);
361 size = sizeof(default_buf)/sizeof(default_buf[0]);
365 n = (*get_config)(name, buf, size, &error);
367 mconsole_reply(req, error, 1, 0);
372 mconsole_reply(req, buf, 0, 0);
376 if(buf != default_buf)
380 buf = kmalloc(size, GFP_KERNEL);
382 mconsole_reply(req, "Failed to allocate buffer", 1, 0);
387 if(buf != default_buf)
392 void mconsole_config(struct mc_request *req)
394 struct mc_device *dev;
395 char *ptr = req->request.data, *name;
398 ptr += strlen("config");
399 while(isspace(*ptr)) ptr++;
400 dev = mconsole_find_dev(ptr);
402 mconsole_reply(req, "Bad configuration option", 1, 0);
406 name = &ptr[strlen(dev->name)];
408 while((*ptr != '=') && (*ptr != '\0'))
412 err = (*dev->config)(name);
413 mconsole_reply(req, "", err, 0);
415 else mconsole_get_config(dev->get_config, req, name);
418 void mconsole_remove(struct mc_request *req)
420 struct mc_device *dev;
421 char *ptr = req->request.data;
424 ptr += strlen("remove");
425 while(isspace(*ptr)) ptr++;
426 dev = mconsole_find_dev(ptr);
428 mconsole_reply(req, "Bad remove option", 1, 0);
431 err = (*dev->remove)(&ptr[strlen(dev->name)]);
432 mconsole_reply(req, "", err, 0);
435 #ifdef CONFIG_MAGIC_SYSRQ
436 void mconsole_sysrq(struct mc_request *req)
438 char *ptr = req->request.data;
440 ptr += strlen("sysrq");
441 while(isspace(*ptr)) ptr++;
443 mconsole_reply(req, "", 0, 0);
444 handle_sysrq(*ptr, ¤t->thread.regs, NULL);
447 void mconsole_sysrq(struct mc_request *req)
449 mconsole_reply(req, "Sysrq not compiled in", 1, 0);
453 /* Changed by mconsole_setup, which is __setup, and called before SMP is
456 static char *notify_socket = NULL;
458 int mconsole_init(void)
463 if(umid_file_name("mconsole", file, sizeof(file))) return(-1);
464 snprintf(mconsole_socket_name, sizeof(file), "%s", file);
466 sock = os_create_unix_socket(file, sizeof(file), 1);
468 printk("Failed to initialize management console\n");
472 register_reboot_notifier(&reboot_notifier);
474 err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt,
475 SA_INTERRUPT | SA_SHIRQ | SA_SAMPLE_RANDOM,
476 "mconsole", (void *)sock);
478 printk("Failed to get IRQ for management console\n");
482 if(notify_socket != NULL){
483 notify_socket = uml_strdup(notify_socket);
484 if(notify_socket != NULL)
485 mconsole_notify(notify_socket, MCONSOLE_SOCKET,
486 mconsole_socket_name,
487 strlen(mconsole_socket_name) + 1);
488 else printk(KERN_ERR "mconsole_setup failed to strdup "
492 printk("mconsole (version %d) initialized on %s\n",
493 MCONSOLE_VERSION, mconsole_socket_name);
497 __initcall(mconsole_init);
499 static int write_proc_mconsole(struct file *file, const char *buffer,
500 unsigned long count, void *data)
504 buf = kmalloc(count + 1, GFP_KERNEL);
508 if(copy_from_user(buf, buffer, count)){
515 mconsole_notify(notify_socket, MCONSOLE_USER_NOTIFY, buf, count);
521 static int create_proc_mconsole(void)
523 struct proc_dir_entry *ent;
525 if(notify_socket == NULL) return(0);
527 ent = create_proc_entry("mconsole", S_IFREG | 0200, NULL);
529 printk("create_proc_mconsole : create_proc_entry failed\n");
533 ent->read_proc = NULL;
534 ent->write_proc = write_proc_mconsole;
538 static spinlock_t notify_spinlock = SPIN_LOCK_UNLOCKED;
540 void lock_notify(void)
542 spin_lock(¬ify_spinlock);
545 void unlock_notify(void)
547 spin_unlock(¬ify_spinlock);
550 __initcall(create_proc_mconsole);
552 #define NOTIFY "=notify:"
554 static int mconsole_setup(char *str)
556 if(!strncmp(str, NOTIFY, strlen(NOTIFY))){
557 str += strlen(NOTIFY);
560 else printk(KERN_ERR "mconsole_setup : Unknown option - '%s'\n", str);
564 __setup("mconsole", mconsole_setup);
566 __uml_help(mconsole_setup,
567 "mconsole=notify:<socket>\n"
568 " Requests that the mconsole driver send a message to the named Unix\n"
569 " socket containing the name of the mconsole socket. This also serves\n"
570 " to notify outside processes when UML has booted far enough to respond\n"
571 " to mconsole requests.\n\n"
574 static int notify_panic(struct notifier_block *self, unsigned long unused1,
579 if(notify_socket == NULL) return(0);
581 mconsole_notify(notify_socket, MCONSOLE_PANIC, message,
582 strlen(message) + 1);
586 static struct notifier_block panic_exit_notifier = {
587 .notifier_call = notify_panic,
592 static int add_notifier(void)
594 notifier_chain_register(&panic_notifier_list, &panic_exit_notifier);
598 __initcall(add_notifier);
600 char *mconsole_notify_socket(void)
602 return(notify_socket);
605 EXPORT_SYMBOL(mconsole_notify_socket);
608 * Overrides for Emacs so that we follow Linus's tabbing style.
609 * Emacs will notice this stuff at the end of the file and automatically
610 * adjust the settings for this buffer only. This must remain at the end
612 * ---------------------------------------------------------------------------
614 * c-file-style: "linux"