]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) | |
3 | * Copyright (C) 2001 - 2003 Jeff Dike (jdike@addtoit.com) | |
4 | * Licensed under the GPL | |
5 | */ | |
6 | ||
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" | |
19 | #include "linux/fs.h" | |
20 | #include "linux/namei.h" | |
21 | #include "linux/proc_fs.h" | |
22 | #include "linux/syscalls.h" | |
23 | #include "asm/irq.h" | |
24 | #include "asm/uaccess.h" | |
25 | #include "user_util.h" | |
26 | #include "kern_util.h" | |
27 | #include "kern.h" | |
28 | #include "mconsole.h" | |
29 | #include "mconsole_kern.h" | |
30 | #include "irq_user.h" | |
31 | #include "init.h" | |
32 | #include "os.h" | |
33 | #include "umid.h" | |
34 | #include "irq_kern.h" | |
35 | ||
36 | static int do_unlink_socket(struct notifier_block *notifier, | |
37 | unsigned long what, void *data) | |
38 | { | |
39 | return(mconsole_unlink_socket()); | |
40 | } | |
41 | ||
42 | ||
43 | static struct notifier_block reboot_notifier = { | |
44 | .notifier_call = do_unlink_socket, | |
45 | .priority = 0, | |
46 | }; | |
47 | ||
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. | |
51 | */ | |
52 | ||
53 | LIST_HEAD(mc_requests); | |
54 | ||
55 | static void mc_work_proc(void *unused) | |
56 | { | |
57 | struct mconsole_entry *req; | |
58 | unsigned long flags; | |
59 | ||
60 | while(!list_empty(&mc_requests)){ | |
61 | local_save_flags(flags); | |
62 | req = list_entry(mc_requests.next, struct mconsole_entry, | |
63 | list); | |
64 | list_del(&req->list); | |
65 | local_irq_restore(flags); | |
66 | req->request.cmd->handler(&req->request); | |
67 | kfree(req); | |
68 | } | |
69 | } | |
70 | ||
71 | DECLARE_WORK(mconsole_work, mc_work_proc, NULL); | |
72 | ||
73 | static irqreturn_t mconsole_interrupt(int irq, void *dev_id, | |
74 | struct pt_regs *regs) | |
75 | { | |
76 | /* long to avoid size mismatch warnings from gcc */ | |
77 | long fd; | |
78 | struct mconsole_entry *new; | |
79 | struct mc_request req; | |
80 | ||
81 | fd = (long) dev_id; | |
82 | while (mconsole_get_request(fd, &req)){ | |
83 | if(req.cmd->context == MCONSOLE_INTR) | |
84 | (*req.cmd->handler)(&req); | |
85 | else { | |
86 | new = kmalloc(sizeof(*new), GFP_ATOMIC); | |
87 | if(new == NULL) | |
88 | mconsole_reply(&req, "Out of memory", 1, 0); | |
89 | else { | |
90 | new->request = req; | |
91 | list_add(&new->list, &mc_requests); | |
92 | } | |
93 | } | |
94 | } | |
95 | if(!list_empty(&mc_requests)) | |
96 | schedule_work(&mconsole_work); | |
97 | reactivate_fd(fd, MCONSOLE_IRQ); | |
98 | return(IRQ_HANDLED); | |
99 | } | |
100 | ||
101 | void mconsole_version(struct mc_request *req) | |
102 | { | |
103 | char version[256]; | |
104 | ||
105 | sprintf(version, "%s %s %s %s %s", system_utsname.sysname, | |
106 | system_utsname.nodename, system_utsname.release, | |
107 | system_utsname.version, system_utsname.machine); | |
108 | mconsole_reply(req, version, 0, 0); | |
109 | } | |
110 | ||
111 | void mconsole_log(struct mc_request *req) | |
112 | { | |
113 | int len; | |
114 | char *ptr = req->request.data; | |
115 | ||
116 | ptr += strlen("log "); | |
117 | ||
118 | len = req->len - (ptr - req->request.data); | |
119 | printk("%.*s", len, ptr); | |
120 | mconsole_reply(req, "", 0, 0); | |
121 | } | |
122 | ||
123 | /* This is a more convoluted version of mconsole_proc, which has some stability | |
124 | * problems; however, we need it fixed, because it is expected that UML users | |
125 | * mount HPPFS instead of procfs on /proc. And we want mconsole_proc to still | |
126 | * show the real procfs content, not the ones from hppfs.*/ | |
127 | #if 0 | |
128 | void mconsole_proc(struct mc_request *req) | |
129 | { | |
130 | struct nameidata nd; | |
131 | struct file_system_type *proc; | |
132 | struct super_block *super; | |
133 | struct file *file; | |
134 | int n, err; | |
135 | char *ptr = req->request.data, *buf; | |
136 | ||
137 | ptr += strlen("proc"); | |
138 | while(isspace(*ptr)) ptr++; | |
139 | ||
140 | proc = get_fs_type("proc"); | |
141 | if(proc == NULL){ | |
142 | mconsole_reply(req, "procfs not registered", 1, 0); | |
143 | goto out; | |
144 | } | |
145 | ||
146 | super = (*proc->get_sb)(proc, 0, NULL, NULL); | |
147 | put_filesystem(proc); | |
148 | if(super == NULL){ | |
149 | mconsole_reply(req, "Failed to get procfs superblock", 1, 0); | |
150 | goto out; | |
151 | } | |
152 | up_write(&super->s_umount); | |
153 | ||
154 | nd.dentry = super->s_root; | |
155 | nd.mnt = NULL; | |
156 | nd.flags = O_RDONLY + 1; | |
157 | nd.last_type = LAST_ROOT; | |
158 | ||
159 | /* START: it was experienced that the stability problems are closed | |
160 | * if commenting out these two calls + the below read cycle. To | |
161 | * make UML crash again, it was enough to readd either one.*/ | |
162 | err = link_path_walk(ptr, &nd); | |
163 | if(err){ | |
164 | mconsole_reply(req, "Failed to look up file", 1, 0); | |
165 | goto out_kill; | |
166 | } | |
167 | ||
168 | file = dentry_open(nd.dentry, nd.mnt, O_RDONLY); | |
169 | if(IS_ERR(file)){ | |
170 | mconsole_reply(req, "Failed to open file", 1, 0); | |
171 | goto out_kill; | |
172 | } | |
173 | /*END*/ | |
174 | ||
175 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
176 | if(buf == NULL){ | |
177 | mconsole_reply(req, "Failed to allocate buffer", 1, 0); | |
178 | goto out_fput; | |
179 | } | |
180 | ||
181 | if((file->f_op != NULL) && (file->f_op->read != NULL)){ | |
182 | do { | |
183 | n = (*file->f_op->read)(file, buf, PAGE_SIZE - 1, | |
184 | &file->f_pos); | |
185 | if(n >= 0){ | |
186 | buf[n] = '\0'; | |
187 | mconsole_reply(req, buf, 0, (n > 0)); | |
188 | } | |
189 | else { | |
190 | mconsole_reply(req, "Read of file failed", | |
191 | 1, 0); | |
192 | goto out_free; | |
193 | } | |
194 | } while(n > 0); | |
195 | } | |
196 | else mconsole_reply(req, "", 0, 0); | |
197 | ||
198 | out_free: | |
199 | kfree(buf); | |
200 | out_fput: | |
201 | fput(file); | |
202 | out_kill: | |
203 | deactivate_super(super); | |
204 | out: ; | |
205 | } | |
206 | #endif | |
207 | ||
208 | void mconsole_proc(struct mc_request *req) | |
209 | { | |
210 | char path[64]; | |
211 | char *buf; | |
212 | int len; | |
213 | int fd; | |
214 | int first_chunk = 1; | |
215 | char *ptr = req->request.data; | |
216 | ||
217 | ptr += strlen("proc"); | |
218 | while(isspace(*ptr)) ptr++; | |
219 | snprintf(path, sizeof(path), "/proc/%s", ptr); | |
220 | ||
221 | fd = sys_open(path, 0, 0); | |
222 | if (fd < 0) { | |
223 | mconsole_reply(req, "Failed to open file", 1, 0); | |
224 | printk("open %s: %d\n",path,fd); | |
225 | goto out; | |
226 | } | |
227 | ||
228 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
229 | if(buf == NULL){ | |
230 | mconsole_reply(req, "Failed to allocate buffer", 1, 0); | |
231 | goto out_close; | |
232 | } | |
233 | ||
234 | for (;;) { | |
235 | len = sys_read(fd, buf, PAGE_SIZE-1); | |
236 | if (len < 0) { | |
237 | mconsole_reply(req, "Read of file failed", 1, 0); | |
238 | goto out_free; | |
239 | } | |
240 | /*Begin the file content on his own line.*/ | |
241 | if (first_chunk) { | |
242 | mconsole_reply(req, "\n", 0, 1); | |
243 | first_chunk = 0; | |
244 | } | |
245 | if (len == PAGE_SIZE-1) { | |
246 | buf[len] = '\0'; | |
247 | mconsole_reply(req, buf, 0, 1); | |
248 | } else { | |
249 | buf[len] = '\0'; | |
250 | mconsole_reply(req, buf, 0, 0); | |
251 | break; | |
252 | } | |
253 | } | |
254 | ||
255 | out_free: | |
256 | kfree(buf); | |
257 | out_close: | |
258 | sys_close(fd); | |
259 | out: | |
260 | /* nothing */; | |
261 | } | |
262 | ||
263 | #define UML_MCONSOLE_HELPTEXT \ | |
264 | "Commands: \n\ | |
265 | version - Get kernel version \n\ | |
266 | help - Print this message \n\ | |
267 | halt - Halt UML \n\ | |
268 | reboot - Reboot UML \n\ | |
269 | config <dev>=<config> - Add a new device to UML; \n\ | |
270 | same syntax as command line \n\ | |
271 | config <dev> - Query the configuration of a device \n\ | |
272 | remove <dev> - Remove a device from UML \n\ | |
273 | sysrq <letter> - Performs the SysRq action controlled by the letter \n\ | |
274 | cad - invoke the Ctl-Alt-Del handler \n\ | |
275 | stop - pause the UML; it will do nothing until it receives a 'go' \n\ | |
276 | go - continue the UML after a 'stop' \n\ | |
277 | log <string> - make UML enter <string> into the kernel log\n\ | |
278 | proc <file> - returns the contents of the UML's /proc/<file>\n\ | |
279 | " | |
280 | ||
281 | void mconsole_help(struct mc_request *req) | |
282 | { | |
283 | mconsole_reply(req, UML_MCONSOLE_HELPTEXT, 0, 0); | |
284 | } | |
285 | ||
286 | void mconsole_halt(struct mc_request *req) | |
287 | { | |
288 | mconsole_reply(req, "", 0, 0); | |
289 | machine_halt(); | |
290 | } | |
291 | ||
292 | void mconsole_reboot(struct mc_request *req) | |
293 | { | |
294 | mconsole_reply(req, "", 0, 0); | |
295 | machine_restart(NULL); | |
296 | } | |
297 | ||
298 | extern void ctrl_alt_del(void); | |
299 | ||
300 | void mconsole_cad(struct mc_request *req) | |
301 | { | |
302 | mconsole_reply(req, "", 0, 0); | |
303 | ctrl_alt_del(); | |
304 | } | |
305 | ||
306 | void mconsole_go(struct mc_request *req) | |
307 | { | |
308 | mconsole_reply(req, "Not stopped", 1, 0); | |
309 | } | |
310 | ||
311 | void mconsole_stop(struct mc_request *req) | |
312 | { | |
313 | deactivate_fd(req->originating_fd, MCONSOLE_IRQ); | |
314 | os_set_fd_block(req->originating_fd, 1); | |
315 | mconsole_reply(req, "", 0, 0); | |
316 | while(mconsole_get_request(req->originating_fd, req)){ | |
317 | if(req->cmd->handler == mconsole_go) break; | |
318 | (*req->cmd->handler)(req); | |
319 | } | |
320 | os_set_fd_block(req->originating_fd, 0); | |
321 | reactivate_fd(req->originating_fd, MCONSOLE_IRQ); | |
322 | mconsole_reply(req, "", 0, 0); | |
323 | } | |
324 | ||
325 | /* This list is populated by __initcall routines. */ | |
326 | ||
327 | LIST_HEAD(mconsole_devices); | |
328 | ||
329 | void mconsole_register_dev(struct mc_device *new) | |
330 | { | |
331 | list_add(&new->list, &mconsole_devices); | |
332 | } | |
333 | ||
334 | static struct mc_device *mconsole_find_dev(char *name) | |
335 | { | |
336 | struct list_head *ele; | |
337 | struct mc_device *dev; | |
338 | ||
339 | list_for_each(ele, &mconsole_devices){ | |
340 | dev = list_entry(ele, struct mc_device, list); | |
341 | if(!strncmp(name, dev->name, strlen(dev->name))) | |
342 | return(dev); | |
343 | } | |
344 | return(NULL); | |
345 | } | |
346 | ||
347 | #define CONFIG_BUF_SIZE 64 | |
348 | ||
349 | static void mconsole_get_config(int (*get_config)(char *, char *, int, | |
350 | char **), | |
351 | struct mc_request *req, char *name) | |
352 | { | |
353 | char default_buf[CONFIG_BUF_SIZE], *error, *buf; | |
354 | int n, size; | |
355 | ||
356 | if(get_config == NULL){ | |
357 | mconsole_reply(req, "No get_config routine defined", 1, 0); | |
358 | return; | |
359 | } | |
360 | ||
361 | error = NULL; | |
362 | size = sizeof(default_buf)/sizeof(default_buf[0]); | |
363 | buf = default_buf; | |
364 | ||
365 | while(1){ | |
366 | n = (*get_config)(name, buf, size, &error); | |
367 | if(error != NULL){ | |
368 | mconsole_reply(req, error, 1, 0); | |
369 | goto out; | |
370 | } | |
371 | ||
372 | if(n <= size){ | |
373 | mconsole_reply(req, buf, 0, 0); | |
374 | goto out; | |
375 | } | |
376 | ||
377 | if(buf != default_buf) | |
378 | kfree(buf); | |
379 | ||
380 | size = n; | |
381 | buf = kmalloc(size, GFP_KERNEL); | |
382 | if(buf == NULL){ | |
383 | mconsole_reply(req, "Failed to allocate buffer", 1, 0); | |
384 | return; | |
385 | } | |
386 | } | |
387 | out: | |
388 | if(buf != default_buf) | |
389 | kfree(buf); | |
390 | ||
391 | } | |
392 | ||
393 | void mconsole_config(struct mc_request *req) | |
394 | { | |
395 | struct mc_device *dev; | |
396 | char *ptr = req->request.data, *name; | |
397 | int err; | |
398 | ||
399 | ptr += strlen("config"); | |
400 | while(isspace(*ptr)) ptr++; | |
401 | dev = mconsole_find_dev(ptr); | |
402 | if(dev == NULL){ | |
403 | mconsole_reply(req, "Bad configuration option", 1, 0); | |
404 | return; | |
405 | } | |
406 | ||
407 | name = &ptr[strlen(dev->name)]; | |
408 | ptr = name; | |
409 | while((*ptr != '=') && (*ptr != '\0')) | |
410 | ptr++; | |
411 | ||
412 | if(*ptr == '='){ | |
413 | err = (*dev->config)(name); | |
414 | mconsole_reply(req, "", err, 0); | |
415 | } | |
416 | else mconsole_get_config(dev->get_config, req, name); | |
417 | } | |
418 | ||
419 | void mconsole_remove(struct mc_request *req) | |
420 | { | |
421 | struct mc_device *dev; | |
422 | char *ptr = req->request.data; | |
423 | int err; | |
424 | ||
425 | ptr += strlen("remove"); | |
426 | while(isspace(*ptr)) ptr++; | |
427 | dev = mconsole_find_dev(ptr); | |
428 | if(dev == NULL){ | |
429 | mconsole_reply(req, "Bad remove option", 1, 0); | |
430 | return; | |
431 | } | |
432 | err = (*dev->remove)(&ptr[strlen(dev->name)]); | |
433 | mconsole_reply(req, "", err, 0); | |
434 | } | |
435 | ||
436 | #ifdef CONFIG_MAGIC_SYSRQ | |
437 | void mconsole_sysrq(struct mc_request *req) | |
438 | { | |
439 | char *ptr = req->request.data; | |
440 | ||
441 | ptr += strlen("sysrq"); | |
442 | while(isspace(*ptr)) ptr++; | |
443 | ||
444 | mconsole_reply(req, "", 0, 0); | |
445 | handle_sysrq(*ptr, ¤t->thread.regs, NULL); | |
446 | } | |
447 | #else | |
448 | void mconsole_sysrq(struct mc_request *req) | |
449 | { | |
450 | mconsole_reply(req, "Sysrq not compiled in", 1, 0); | |
451 | } | |
452 | #endif | |
453 | ||
454 | /* Changed by mconsole_setup, which is __setup, and called before SMP is | |
455 | * active. | |
456 | */ | |
457 | static char *notify_socket = NULL; | |
458 | ||
459 | int mconsole_init(void) | |
460 | { | |
461 | /* long to avoid size mismatch warnings from gcc */ | |
462 | long sock; | |
463 | int err; | |
464 | char file[256]; | |
465 | ||
466 | if(umid_file_name("mconsole", file, sizeof(file))) return(-1); | |
467 | snprintf(mconsole_socket_name, sizeof(file), "%s", file); | |
468 | ||
469 | sock = os_create_unix_socket(file, sizeof(file), 1); | |
470 | if (sock < 0){ | |
471 | printk("Failed to initialize management console\n"); | |
472 | return(1); | |
473 | } | |
474 | ||
475 | register_reboot_notifier(&reboot_notifier); | |
476 | ||
477 | err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt, | |
478 | SA_INTERRUPT | SA_SHIRQ | SA_SAMPLE_RANDOM, | |
479 | "mconsole", (void *)sock); | |
480 | if (err){ | |
481 | printk("Failed to get IRQ for management console\n"); | |
482 | return(1); | |
483 | } | |
484 | ||
485 | if(notify_socket != NULL){ | |
486 | notify_socket = uml_strdup(notify_socket); | |
487 | if(notify_socket != NULL) | |
488 | mconsole_notify(notify_socket, MCONSOLE_SOCKET, | |
489 | mconsole_socket_name, | |
490 | strlen(mconsole_socket_name) + 1); | |
491 | else printk(KERN_ERR "mconsole_setup failed to strdup " | |
492 | "string\n"); | |
493 | } | |
494 | ||
495 | printk("mconsole (version %d) initialized on %s\n", | |
496 | MCONSOLE_VERSION, mconsole_socket_name); | |
497 | return(0); | |
498 | } | |
499 | ||
500 | __initcall(mconsole_init); | |
501 | ||
502 | static int write_proc_mconsole(struct file *file, const char __user *buffer, | |
503 | unsigned long count, void *data) | |
504 | { | |
505 | char *buf; | |
506 | ||
507 | buf = kmalloc(count + 1, GFP_KERNEL); | |
508 | if(buf == NULL) | |
509 | return(-ENOMEM); | |
510 | ||
511 | if(copy_from_user(buf, buffer, count)){ | |
512 | count = -EFAULT; | |
513 | goto out; | |
514 | } | |
515 | ||
516 | buf[count] = '\0'; | |
517 | ||
518 | mconsole_notify(notify_socket, MCONSOLE_USER_NOTIFY, buf, count); | |
519 | out: | |
520 | kfree(buf); | |
521 | return(count); | |
522 | } | |
523 | ||
524 | static int create_proc_mconsole(void) | |
525 | { | |
526 | struct proc_dir_entry *ent; | |
527 | ||
528 | if(notify_socket == NULL) return(0); | |
529 | ||
530 | ent = create_proc_entry("mconsole", S_IFREG | 0200, NULL); | |
531 | if(ent == NULL){ | |
532 | printk("create_proc_mconsole : create_proc_entry failed\n"); | |
533 | return(0); | |
534 | } | |
535 | ||
536 | ent->read_proc = NULL; | |
537 | ent->write_proc = write_proc_mconsole; | |
538 | return(0); | |
539 | } | |
540 | ||
541 | static DEFINE_SPINLOCK(notify_spinlock); | |
542 | ||
543 | void lock_notify(void) | |
544 | { | |
545 | spin_lock(¬ify_spinlock); | |
546 | } | |
547 | ||
548 | void unlock_notify(void) | |
549 | { | |
550 | spin_unlock(¬ify_spinlock); | |
551 | } | |
552 | ||
553 | __initcall(create_proc_mconsole); | |
554 | ||
555 | #define NOTIFY "=notify:" | |
556 | ||
557 | static int mconsole_setup(char *str) | |
558 | { | |
559 | if(!strncmp(str, NOTIFY, strlen(NOTIFY))){ | |
560 | str += strlen(NOTIFY); | |
561 | notify_socket = str; | |
562 | } | |
563 | else printk(KERN_ERR "mconsole_setup : Unknown option - '%s'\n", str); | |
564 | return(1); | |
565 | } | |
566 | ||
567 | __setup("mconsole", mconsole_setup); | |
568 | ||
569 | __uml_help(mconsole_setup, | |
570 | "mconsole=notify:<socket>\n" | |
571 | " Requests that the mconsole driver send a message to the named Unix\n" | |
572 | " socket containing the name of the mconsole socket. This also serves\n" | |
573 | " to notify outside processes when UML has booted far enough to respond\n" | |
574 | " to mconsole requests.\n\n" | |
575 | ); | |
576 | ||
577 | static int notify_panic(struct notifier_block *self, unsigned long unused1, | |
578 | void *ptr) | |
579 | { | |
580 | char *message = ptr; | |
581 | ||
582 | if(notify_socket == NULL) return(0); | |
583 | ||
584 | mconsole_notify(notify_socket, MCONSOLE_PANIC, message, | |
585 | strlen(message) + 1); | |
586 | return(0); | |
587 | } | |
588 | ||
589 | static struct notifier_block panic_exit_notifier = { | |
590 | .notifier_call = notify_panic, | |
591 | .next = NULL, | |
592 | .priority = 1 | |
593 | }; | |
594 | ||
595 | static int add_notifier(void) | |
596 | { | |
597 | notifier_chain_register(&panic_notifier_list, &panic_exit_notifier); | |
598 | return(0); | |
599 | } | |
600 | ||
601 | __initcall(add_notifier); | |
602 | ||
603 | char *mconsole_notify_socket(void) | |
604 | { | |
605 | return(notify_socket); | |
606 | } | |
607 | ||
608 | EXPORT_SYMBOL(mconsole_notify_socket); | |
609 | ||
610 | /* | |
611 | * Overrides for Emacs so that we follow Linus's tabbing style. | |
612 | * Emacs will notice this stuff at the end of the file and automatically | |
613 | * adjust the settings for this buffer only. This must remain at the end | |
614 | * of the file. | |
615 | * --------------------------------------------------------------------------- | |
616 | * Local variables: | |
617 | * c-file-style: "linux" | |
618 | * End: | |
619 | */ |