Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) | |
827b3f6a | 3 | * Copyright (C) 2001 - 2008 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
1da177e4 LT |
4 | * Licensed under the GPL |
5 | */ | |
6 | ||
827b3f6a JD |
7 | #include <linux/console.h> |
8 | #include <linux/ctype.h> | |
e7d2860b | 9 | #include <linux/string.h> |
827b3f6a JD |
10 | #include <linux/interrupt.h> |
11 | #include <linux/list.h> | |
12 | #include <linux/mm.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/notifier.h> | |
15 | #include <linux/reboot.h> | |
16 | #include <linux/proc_fs.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/syscalls.h> | |
19 | #include <linux/utsname.h> | |
36137120 BS |
20 | #include <linux/socket.h> |
21 | #include <linux/un.h> | |
827b3f6a JD |
22 | #include <linux/workqueue.h> |
23 | #include <linux/mutex.h> | |
723a1d77 AV |
24 | #include <linux/fs.h> |
25 | #include <linux/mount.h> | |
26 | #include <linux/file.h> | |
827b3f6a | 27 | #include <asm/uaccess.h> |
a3a85a76 | 28 | #include <asm/switch_to.h> |
827b3f6a | 29 | |
ae2587e4 JD |
30 | #include "init.h" |
31 | #include "irq_kern.h" | |
32 | #include "irq_user.h" | |
1da177e4 | 33 | #include "kern_util.h" |
1da177e4 LT |
34 | #include "mconsole.h" |
35 | #include "mconsole_kern.h" | |
1da177e4 | 36 | #include "os.h" |
1da177e4 | 37 | |
d50084a2 | 38 | static int do_unlink_socket(struct notifier_block *notifier, |
1da177e4 LT |
39 | unsigned long what, void *data) |
40 | { | |
ae2587e4 | 41 | return mconsole_unlink_socket(); |
1da177e4 LT |
42 | } |
43 | ||
44 | ||
45 | static struct notifier_block reboot_notifier = { | |
46 | .notifier_call = do_unlink_socket, | |
47 | .priority = 0, | |
48 | }; | |
49 | ||
d50084a2 | 50 | /* Safe without explicit locking for now. Tasklets provide their own |
1da177e4 LT |
51 | * locking, and the interrupt handler is safe because it can't interrupt |
52 | * itself and it can only happen on CPU 0. | |
53 | */ | |
54 | ||
9010772c | 55 | static LIST_HEAD(mc_requests); |
1da177e4 | 56 | |
6d5aefb8 | 57 | static void mc_work_proc(struct work_struct *unused) |
1da177e4 LT |
58 | { |
59 | struct mconsole_entry *req; | |
60 | unsigned long flags; | |
61 | ||
ae2587e4 | 62 | while (!list_empty(&mc_requests)) { |
dbdb4c06 | 63 | local_irq_save(flags); |
ae2587e4 | 64 | req = list_entry(mc_requests.next, struct mconsole_entry, list); |
1da177e4 LT |
65 | list_del(&req->list); |
66 | local_irq_restore(flags); | |
67 | req->request.cmd->handler(&req->request); | |
68 | kfree(req); | |
69 | } | |
70 | } | |
71 | ||
6d5aefb8 | 72 | static DECLARE_WORK(mconsole_work, mc_work_proc); |
1da177e4 | 73 | |
7bea96fd | 74 | static irqreturn_t mconsole_interrupt(int irq, void *dev_id) |
1da177e4 LT |
75 | { |
76 | /* long to avoid size mismatch warnings from gcc */ | |
77 | long fd; | |
78 | struct mconsole_entry *new; | |
3a51237d | 79 | static struct mc_request req; /* that's OK */ |
1da177e4 LT |
80 | |
81 | fd = (long) dev_id; | |
ae2587e4 JD |
82 | while (mconsole_get_request(fd, &req)) { |
83 | if (req.cmd->context == MCONSOLE_INTR) | |
1da177e4 LT |
84 | (*req.cmd->handler)(&req); |
85 | else { | |
60baa158 | 86 | new = kmalloc(sizeof(*new), GFP_NOWAIT); |
ae2587e4 | 87 | if (new == NULL) |
1da177e4 LT |
88 | mconsole_reply(&req, "Out of memory", 1, 0); |
89 | else { | |
90 | new->request = req; | |
3a51237d | 91 | new->request.regs = get_irq_regs()->regs; |
1da177e4 LT |
92 | list_add(&new->list, &mc_requests); |
93 | } | |
94 | } | |
95 | } | |
ae2587e4 | 96 | if (!list_empty(&mc_requests)) |
1da177e4 LT |
97 | schedule_work(&mconsole_work); |
98 | reactivate_fd(fd, MCONSOLE_IRQ); | |
ae2587e4 | 99 | return IRQ_HANDLED; |
1da177e4 LT |
100 | } |
101 | ||
102 | void mconsole_version(struct mc_request *req) | |
103 | { | |
104 | char version[256]; | |
105 | ||
e9ff3990 | 106 | sprintf(version, "%s %s %s %s %s", utsname()->sysname, |
ae2587e4 JD |
107 | utsname()->nodename, utsname()->release, utsname()->version, |
108 | utsname()->machine); | |
1da177e4 LT |
109 | mconsole_reply(req, version, 0, 0); |
110 | } | |
111 | ||
112 | void mconsole_log(struct mc_request *req) | |
113 | { | |
114 | int len; | |
115 | char *ptr = req->request.data; | |
116 | ||
117 | ptr += strlen("log "); | |
118 | ||
119 | len = req->len - (ptr - req->request.data); | |
ae2587e4 | 120 | printk(KERN_WARNING "%.*s", len, ptr); |
1da177e4 LT |
121 | mconsole_reply(req, "", 0, 0); |
122 | } | |
123 | ||
1da177e4 LT |
124 | void mconsole_proc(struct mc_request *req) |
125 | { | |
4ecf09fd | 126 | struct vfsmount *mnt = current->nsproxy->pid_ns->proc_mnt; |
1da177e4 LT |
127 | char *buf; |
128 | int len; | |
723a1d77 | 129 | struct file *file; |
1da177e4 LT |
130 | int first_chunk = 1; |
131 | char *ptr = req->request.data; | |
132 | ||
133 | ptr += strlen("proc"); | |
e7d2860b | 134 | ptr = skip_spaces(ptr); |
1da177e4 | 135 | |
723a1d77 AV |
136 | file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY); |
137 | if (IS_ERR(file)) { | |
1da177e4 | 138 | mconsole_reply(req, "Failed to open file", 1, 0); |
723a1d77 | 139 | printk(KERN_ERR "open /proc/%s: %ld\n", ptr, PTR_ERR(file)); |
1da177e4 LT |
140 | goto out; |
141 | } | |
142 | ||
143 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
ae2587e4 | 144 | if (buf == NULL) { |
1da177e4 | 145 | mconsole_reply(req, "Failed to allocate buffer", 1, 0); |
723a1d77 | 146 | goto out_fput; |
1da177e4 LT |
147 | } |
148 | ||
723a1d77 AV |
149 | do { |
150 | loff_t pos; | |
151 | mm_segment_t old_fs = get_fs(); | |
152 | set_fs(KERNEL_DS); | |
153 | len = vfs_read(file, buf, PAGE_SIZE - 1, &pos); | |
154 | set_fs(old_fs); | |
155 | file->f_pos = pos; | |
1da177e4 LT |
156 | if (len < 0) { |
157 | mconsole_reply(req, "Read of file failed", 1, 0); | |
158 | goto out_free; | |
159 | } | |
ae2587e4 | 160 | /* Begin the file content on his own line. */ |
1da177e4 LT |
161 | if (first_chunk) { |
162 | mconsole_reply(req, "\n", 0, 1); | |
163 | first_chunk = 0; | |
164 | } | |
723a1d77 AV |
165 | buf[len] = '\0'; |
166 | mconsole_reply(req, buf, 0, (len > 0)); | |
167 | } while (len > 0); | |
1da177e4 LT |
168 | out_free: |
169 | kfree(buf); | |
723a1d77 AV |
170 | out_fput: |
171 | fput(file); | |
172 | out: ; | |
1da177e4 LT |
173 | } |
174 | ||
175 | #define UML_MCONSOLE_HELPTEXT \ | |
176 | "Commands: \n\ | |
177 | version - Get kernel version \n\ | |
178 | help - Print this message \n\ | |
179 | halt - Halt UML \n\ | |
180 | reboot - Reboot UML \n\ | |
181 | config <dev>=<config> - Add a new device to UML; \n\ | |
182 | same syntax as command line \n\ | |
183 | config <dev> - Query the configuration of a device \n\ | |
184 | remove <dev> - Remove a device from UML \n\ | |
185 | sysrq <letter> - Performs the SysRq action controlled by the letter \n\ | |
db805812 | 186 | cad - invoke the Ctrl-Alt-Del handler \n\ |
1da177e4 LT |
187 | stop - pause the UML; it will do nothing until it receives a 'go' \n\ |
188 | go - continue the UML after a 'stop' \n\ | |
189 | log <string> - make UML enter <string> into the kernel log\n\ | |
190 | proc <file> - returns the contents of the UML's /proc/<file>\n\ | |
3eddddcf | 191 | stack <pid> - returns the stack of the specified pid\n\ |
1da177e4 LT |
192 | " |
193 | ||
194 | void mconsole_help(struct mc_request *req) | |
195 | { | |
196 | mconsole_reply(req, UML_MCONSOLE_HELPTEXT, 0, 0); | |
197 | } | |
198 | ||
199 | void mconsole_halt(struct mc_request *req) | |
200 | { | |
201 | mconsole_reply(req, "", 0, 0); | |
202 | machine_halt(); | |
203 | } | |
204 | ||
205 | void mconsole_reboot(struct mc_request *req) | |
206 | { | |
207 | mconsole_reply(req, "", 0, 0); | |
208 | machine_restart(NULL); | |
209 | } | |
210 | ||
1da177e4 LT |
211 | void mconsole_cad(struct mc_request *req) |
212 | { | |
213 | mconsole_reply(req, "", 0, 0); | |
214 | ctrl_alt_del(); | |
215 | } | |
216 | ||
217 | void mconsole_go(struct mc_request *req) | |
218 | { | |
219 | mconsole_reply(req, "Not stopped", 1, 0); | |
220 | } | |
221 | ||
222 | void mconsole_stop(struct mc_request *req) | |
223 | { | |
224 | deactivate_fd(req->originating_fd, MCONSOLE_IRQ); | |
225 | os_set_fd_block(req->originating_fd, 1); | |
3a51237d | 226 | mconsole_reply(req, "stopped", 0, 0); |
cc0be0fb KS |
227 | for (;;) { |
228 | if (!mconsole_get_request(req->originating_fd, req)) | |
229 | continue; | |
3a51237d AV |
230 | if (req->cmd->handler == mconsole_go) |
231 | break; | |
232 | if (req->cmd->handler == mconsole_stop) { | |
233 | mconsole_reply(req, "Already stopped", 1, 0); | |
234 | continue; | |
235 | } | |
236 | if (req->cmd->handler == mconsole_sysrq) { | |
237 | struct pt_regs *old_regs; | |
238 | old_regs = set_irq_regs((struct pt_regs *)&req->regs); | |
239 | mconsole_sysrq(req); | |
240 | set_irq_regs(old_regs); | |
241 | continue; | |
242 | } | |
1da177e4 LT |
243 | (*req->cmd->handler)(req); |
244 | } | |
245 | os_set_fd_block(req->originating_fd, 0); | |
246 | reactivate_fd(req->originating_fd, MCONSOLE_IRQ); | |
247 | mconsole_reply(req, "", 0, 0); | |
248 | } | |
249 | ||
84f48d4f | 250 | static DEFINE_SPINLOCK(mc_devices_lock); |
42947cb9 | 251 | static LIST_HEAD(mconsole_devices); |
1da177e4 LT |
252 | |
253 | void mconsole_register_dev(struct mc_device *new) | |
254 | { | |
84f48d4f JD |
255 | spin_lock(&mc_devices_lock); |
256 | BUG_ON(!list_empty(&new->list)); | |
1da177e4 | 257 | list_add(&new->list, &mconsole_devices); |
84f48d4f | 258 | spin_unlock(&mc_devices_lock); |
1da177e4 LT |
259 | } |
260 | ||
261 | static struct mc_device *mconsole_find_dev(char *name) | |
262 | { | |
263 | struct list_head *ele; | |
264 | struct mc_device *dev; | |
265 | ||
ae2587e4 | 266 | list_for_each(ele, &mconsole_devices) { |
1da177e4 | 267 | dev = list_entry(ele, struct mc_device, list); |
ae2587e4 JD |
268 | if (!strncmp(name, dev->name, strlen(dev->name))) |
269 | return dev; | |
1da177e4 | 270 | } |
ae2587e4 | 271 | return NULL; |
1da177e4 LT |
272 | } |
273 | ||
02dea087 JD |
274 | #define UNPLUGGED_PER_PAGE \ |
275 | ((PAGE_SIZE - sizeof(struct list_head)) / sizeof(unsigned long)) | |
276 | ||
277 | struct unplugged_pages { | |
278 | struct list_head list; | |
279 | void *pages[UNPLUGGED_PER_PAGE]; | |
280 | }; | |
281 | ||
e98fa281 | 282 | static DEFINE_MUTEX(plug_mem_mutex); |
02dea087 | 283 | static unsigned long long unplugged_pages_count = 0; |
c59bce62 | 284 | static LIST_HEAD(unplugged_pages); |
02dea087 JD |
285 | static int unplug_index = UNPLUGGED_PER_PAGE; |
286 | ||
f28169d2 | 287 | static int mem_config(char *str, char **error_out) |
02dea087 JD |
288 | { |
289 | unsigned long long diff; | |
290 | int err = -EINVAL, i, add; | |
291 | char *ret; | |
292 | ||
ae2587e4 | 293 | if (str[0] != '=') { |
f28169d2 | 294 | *error_out = "Expected '=' after 'mem'"; |
02dea087 | 295 | goto out; |
f28169d2 | 296 | } |
02dea087 JD |
297 | |
298 | str++; | |
ae2587e4 | 299 | if (str[0] == '-') |
02dea087 | 300 | add = 0; |
ae2587e4 | 301 | else if (str[0] == '+') { |
02dea087 JD |
302 | add = 1; |
303 | } | |
f28169d2 JD |
304 | else { |
305 | *error_out = "Expected increment to start with '-' or '+'"; | |
306 | goto out; | |
307 | } | |
02dea087 JD |
308 | |
309 | str++; | |
310 | diff = memparse(str, &ret); | |
ae2587e4 | 311 | if (*ret != '\0') { |
f28169d2 | 312 | *error_out = "Failed to parse memory increment"; |
02dea087 | 313 | goto out; |
f28169d2 | 314 | } |
02dea087 JD |
315 | |
316 | diff /= PAGE_SIZE; | |
317 | ||
e98fa281 | 318 | mutex_lock(&plug_mem_mutex); |
ae2587e4 | 319 | for (i = 0; i < diff; i++) { |
02dea087 JD |
320 | struct unplugged_pages *unplugged; |
321 | void *addr; | |
322 | ||
ae2587e4 JD |
323 | if (add) { |
324 | if (list_empty(&unplugged_pages)) | |
02dea087 JD |
325 | break; |
326 | ||
327 | unplugged = list_entry(unplugged_pages.next, | |
328 | struct unplugged_pages, list); | |
ae2587e4 | 329 | if (unplug_index > 0) |
02dea087 JD |
330 | addr = unplugged->pages[--unplug_index]; |
331 | else { | |
332 | list_del(&unplugged->list); | |
333 | addr = unplugged; | |
334 | unplug_index = UNPLUGGED_PER_PAGE; | |
335 | } | |
336 | ||
337 | free_page((unsigned long) addr); | |
338 | unplugged_pages_count--; | |
339 | } | |
340 | else { | |
341 | struct page *page; | |
342 | ||
343 | page = alloc_page(GFP_ATOMIC); | |
ae2587e4 | 344 | if (page == NULL) |
02dea087 JD |
345 | break; |
346 | ||
347 | unplugged = page_address(page); | |
ae2587e4 | 348 | if (unplug_index == UNPLUGGED_PER_PAGE) { |
02dea087 JD |
349 | list_add(&unplugged->list, &unplugged_pages); |
350 | unplug_index = 0; | |
351 | } | |
352 | else { | |
353 | struct list_head *entry = unplugged_pages.next; | |
354 | addr = unplugged; | |
355 | ||
356 | unplugged = list_entry(entry, | |
357 | struct unplugged_pages, | |
358 | list); | |
02dea087 | 359 | err = os_drop_memory(addr, PAGE_SIZE); |
ae2587e4 JD |
360 | if (err) { |
361 | printk(KERN_ERR "Failed to release " | |
362 | "memory - errno = %d\n", err); | |
f28169d2 | 363 | *error_out = "Failed to release memory"; |
84f48d4f | 364 | goto out_unlock; |
f28169d2 JD |
365 | } |
366 | unplugged->pages[unplug_index++] = addr; | |
02dea087 JD |
367 | } |
368 | ||
369 | unplugged_pages_count++; | |
370 | } | |
371 | } | |
372 | ||
373 | err = 0; | |
84f48d4f | 374 | out_unlock: |
e98fa281 | 375 | mutex_unlock(&plug_mem_mutex); |
02dea087 JD |
376 | out: |
377 | return err; | |
378 | } | |
379 | ||
380 | static int mem_get_config(char *name, char *str, int size, char **error_out) | |
381 | { | |
382 | char buf[sizeof("18446744073709551615")]; | |
383 | int len = 0; | |
384 | ||
385 | sprintf(buf, "%ld", uml_physmem); | |
386 | CONFIG_CHUNK(str, size, len, buf, 1); | |
387 | ||
388 | return len; | |
389 | } | |
390 | ||
391 | static int mem_id(char **str, int *start_out, int *end_out) | |
392 | { | |
393 | *start_out = 0; | |
394 | *end_out = 0; | |
395 | ||
396 | return 0; | |
397 | } | |
398 | ||
f28169d2 | 399 | static int mem_remove(int n, char **error_out) |
02dea087 | 400 | { |
f28169d2 | 401 | *error_out = "Memory doesn't support the remove operation"; |
02dea087 JD |
402 | return -EBUSY; |
403 | } | |
404 | ||
405 | static struct mc_device mem_mc = { | |
84f48d4f | 406 | .list = LIST_HEAD_INIT(mem_mc.list), |
02dea087 JD |
407 | .name = "mem", |
408 | .config = mem_config, | |
409 | .get_config = mem_get_config, | |
410 | .id = mem_id, | |
411 | .remove = mem_remove, | |
412 | }; | |
413 | ||
97a1fcbb | 414 | static int __init mem_mc_init(void) |
02dea087 | 415 | { |
ae2587e4 | 416 | if (can_drop_memory()) |
02dea087 | 417 | mconsole_register_dev(&mem_mc); |
ae2587e4 JD |
418 | else printk(KERN_ERR "Can't release memory to the host - memory " |
419 | "hotplug won't be supported\n"); | |
02dea087 JD |
420 | return 0; |
421 | } | |
422 | ||
423 | __initcall(mem_mc_init); | |
424 | ||
1da177e4 LT |
425 | #define CONFIG_BUF_SIZE 64 |
426 | ||
d50084a2 | 427 | static void mconsole_get_config(int (*get_config)(char *, char *, int, |
1da177e4 LT |
428 | char **), |
429 | struct mc_request *req, char *name) | |
430 | { | |
431 | char default_buf[CONFIG_BUF_SIZE], *error, *buf; | |
432 | int n, size; | |
433 | ||
ae2587e4 | 434 | if (get_config == NULL) { |
1da177e4 LT |
435 | mconsole_reply(req, "No get_config routine defined", 1, 0); |
436 | return; | |
437 | } | |
438 | ||
439 | error = NULL; | |
91b165c0 | 440 | size = ARRAY_SIZE(default_buf); |
1da177e4 LT |
441 | buf = default_buf; |
442 | ||
ae2587e4 | 443 | while (1) { |
1da177e4 | 444 | n = (*get_config)(name, buf, size, &error); |
ae2587e4 | 445 | if (error != NULL) { |
1da177e4 LT |
446 | mconsole_reply(req, error, 1, 0); |
447 | goto out; | |
448 | } | |
449 | ||
ae2587e4 | 450 | if (n <= size) { |
1da177e4 LT |
451 | mconsole_reply(req, buf, 0, 0); |
452 | goto out; | |
453 | } | |
454 | ||
ae2587e4 | 455 | if (buf != default_buf) |
1da177e4 LT |
456 | kfree(buf); |
457 | ||
458 | size = n; | |
459 | buf = kmalloc(size, GFP_KERNEL); | |
ae2587e4 | 460 | if (buf == NULL) { |
1da177e4 LT |
461 | mconsole_reply(req, "Failed to allocate buffer", 1, 0); |
462 | return; | |
463 | } | |
464 | } | |
465 | out: | |
ae2587e4 | 466 | if (buf != default_buf) |
1da177e4 | 467 | kfree(buf); |
1da177e4 LT |
468 | } |
469 | ||
470 | void mconsole_config(struct mc_request *req) | |
471 | { | |
472 | struct mc_device *dev; | |
f28169d2 | 473 | char *ptr = req->request.data, *name, *error_string = ""; |
1da177e4 LT |
474 | int err; |
475 | ||
476 | ptr += strlen("config"); | |
e7d2860b | 477 | ptr = skip_spaces(ptr); |
1da177e4 | 478 | dev = mconsole_find_dev(ptr); |
ae2587e4 | 479 | if (dev == NULL) { |
1da177e4 LT |
480 | mconsole_reply(req, "Bad configuration option", 1, 0); |
481 | return; | |
482 | } | |
483 | ||
484 | name = &ptr[strlen(dev->name)]; | |
485 | ptr = name; | |
ae2587e4 | 486 | while ((*ptr != '=') && (*ptr != '\0')) |
1da177e4 LT |
487 | ptr++; |
488 | ||
ae2587e4 | 489 | if (*ptr == '=') { |
f28169d2 JD |
490 | err = (*dev->config)(name, &error_string); |
491 | mconsole_reply(req, error_string, err, 0); | |
1da177e4 LT |
492 | } |
493 | else mconsole_get_config(dev->get_config, req, name); | |
494 | } | |
495 | ||
496 | void mconsole_remove(struct mc_request *req) | |
497 | { | |
d50084a2 | 498 | struct mc_device *dev; |
29d56cfe | 499 | char *ptr = req->request.data, *err_msg = ""; |
3a331a51 | 500 | char error[256]; |
29d56cfe | 501 | int err, start, end, n; |
1da177e4 LT |
502 | |
503 | ptr += strlen("remove"); | |
e7d2860b | 504 | ptr = skip_spaces(ptr); |
1da177e4 | 505 | dev = mconsole_find_dev(ptr); |
ae2587e4 | 506 | if (dev == NULL) { |
1da177e4 LT |
507 | mconsole_reply(req, "Bad remove option", 1, 0); |
508 | return; | |
509 | } | |
29d56cfe | 510 | |
3a331a51 JD |
511 | ptr = &ptr[strlen(dev->name)]; |
512 | ||
513 | err = 1; | |
514 | n = (*dev->id)(&ptr, &start, &end); | |
ae2587e4 | 515 | if (n < 0) { |
3a331a51 JD |
516 | err_msg = "Couldn't parse device number"; |
517 | goto out; | |
518 | } | |
ae2587e4 | 519 | else if ((n < start) || (n > end)) { |
3a331a51 JD |
520 | sprintf(error, "Invalid device number - must be between " |
521 | "%d and %d", start, end); | |
522 | err_msg = error; | |
523 | goto out; | |
524 | } | |
29d56cfe | 525 | |
f28169d2 JD |
526 | err_msg = NULL; |
527 | err = (*dev->remove)(n, &err_msg); | |
ae2587e4 | 528 | switch(err) { |
d40f6d71 JD |
529 | case 0: |
530 | err_msg = ""; | |
531 | break; | |
3a331a51 | 532 | case -ENODEV: |
ae2587e4 | 533 | if (err_msg == NULL) |
f28169d2 | 534 | err_msg = "Device doesn't exist"; |
3a331a51 JD |
535 | break; |
536 | case -EBUSY: | |
ae2587e4 | 537 | if (err_msg == NULL) |
f28169d2 | 538 | err_msg = "Device is currently open"; |
3a331a51 JD |
539 | break; |
540 | default: | |
541 | break; | |
542 | } | |
543 | out: | |
29d56cfe | 544 | mconsole_reply(req, err_msg, err, 0); |
1da177e4 LT |
545 | } |
546 | ||
f92afe56 JD |
547 | struct mconsole_output { |
548 | struct list_head list; | |
549 | struct mc_request *req; | |
550 | }; | |
551 | ||
84f48d4f | 552 | static DEFINE_SPINLOCK(client_lock); |
6f517d3f JD |
553 | static LIST_HEAD(clients); |
554 | static char console_buf[MCONSOLE_MAX_DATA]; | |
6f517d3f JD |
555 | |
556 | static void console_write(struct console *console, const char *string, | |
54fa0ba4 | 557 | unsigned int len) |
6f517d3f JD |
558 | { |
559 | struct list_head *ele; | |
560 | int n; | |
561 | ||
ae2587e4 | 562 | if (list_empty(&clients)) |
6f517d3f JD |
563 | return; |
564 | ||
54fa0ba4 JD |
565 | while (len > 0) { |
566 | n = min((size_t) len, ARRAY_SIZE(console_buf)); | |
567 | strncpy(console_buf, string, n); | |
6f517d3f JD |
568 | string += n; |
569 | len -= n; | |
6f517d3f | 570 | |
ae2587e4 | 571 | list_for_each(ele, &clients) { |
f92afe56 | 572 | struct mconsole_output *entry; |
6f517d3f | 573 | |
f92afe56 | 574 | entry = list_entry(ele, struct mconsole_output, list); |
54fa0ba4 | 575 | mconsole_reply_len(entry->req, console_buf, n, 0, 1); |
6f517d3f | 576 | } |
6f517d3f JD |
577 | } |
578 | } | |
579 | ||
580 | static struct console mc_console = { .name = "mc", | |
581 | .write = console_write, | |
a174b30e | 582 | .flags = CON_ENABLED, |
6f517d3f JD |
583 | .index = -1 }; |
584 | ||
585 | static int mc_add_console(void) | |
586 | { | |
587 | register_console(&mc_console); | |
588 | return 0; | |
589 | } | |
590 | ||
591 | late_initcall(mc_add_console); | |
592 | ||
593 | static void with_console(struct mc_request *req, void (*proc)(void *), | |
594 | void *arg) | |
595 | { | |
f92afe56 | 596 | struct mconsole_output entry; |
6f517d3f JD |
597 | unsigned long flags; |
598 | ||
f92afe56 | 599 | entry.req = req; |
84f48d4f | 600 | spin_lock_irqsave(&client_lock, flags); |
6f517d3f | 601 | list_add(&entry.list, &clients); |
84f48d4f | 602 | spin_unlock_irqrestore(&client_lock, flags); |
6f517d3f JD |
603 | |
604 | (*proc)(arg); | |
605 | ||
54fa0ba4 | 606 | mconsole_reply_len(req, "", 0, 0, 0); |
6f517d3f | 607 | |
84f48d4f | 608 | spin_lock_irqsave(&client_lock, flags); |
6f517d3f | 609 | list_del(&entry.list); |
84f48d4f | 610 | spin_unlock_irqrestore(&client_lock, flags); |
6f517d3f JD |
611 | } |
612 | ||
4111b025 | 613 | #ifdef CONFIG_MAGIC_SYSRQ |
54fa0ba4 JD |
614 | |
615 | #include <linux/sysrq.h> | |
616 | ||
4111b025 JD |
617 | static void sysrq_proc(void *arg) |
618 | { | |
619 | char *op = arg; | |
f335397d | 620 | handle_sysrq(*op); |
4111b025 JD |
621 | } |
622 | ||
623 | void mconsole_sysrq(struct mc_request *req) | |
624 | { | |
625 | char *ptr = req->request.data; | |
626 | ||
627 | ptr += strlen("sysrq"); | |
e7d2860b | 628 | ptr = skip_spaces(ptr); |
4111b025 | 629 | |
ae2587e4 JD |
630 | /* |
631 | * With 'b', the system will shut down without a chance to reply, | |
4111b025 JD |
632 | * so in this case, we reply first. |
633 | */ | |
ae2587e4 | 634 | if (*ptr == 'b') |
4111b025 JD |
635 | mconsole_reply(req, "", 0, 0); |
636 | ||
637 | with_console(req, sysrq_proc, ptr); | |
638 | } | |
639 | #else | |
640 | void mconsole_sysrq(struct mc_request *req) | |
641 | { | |
642 | mconsole_reply(req, "Sysrq not compiled in", 1, 0); | |
643 | } | |
644 | #endif | |
645 | ||
6f517d3f JD |
646 | static void stack_proc(void *arg) |
647 | { | |
648 | struct task_struct *from = current, *to = arg; | |
649 | ||
650 | to->thread.saved_task = from; | |
04e7e951 | 651 | rcu_switch(from, to); |
6f517d3f JD |
652 | switch_to(from, to, from); |
653 | } | |
654 | ||
ae2587e4 JD |
655 | /* |
656 | * Mconsole stack trace | |
3eddddcf JD |
657 | * Added by Allan Graves, Jeff Dike |
658 | * Dumps a stacks registers to the linux console. | |
659 | * Usage stack <pid>. | |
660 | */ | |
42fda663 | 661 | void mconsole_stack(struct mc_request *req) |
3eddddcf | 662 | { |
3a331a51 JD |
663 | char *ptr = req->request.data; |
664 | int pid_requested= -1; | |
3eddddcf JD |
665 | struct task_struct *to = NULL; |
666 | ||
ae2587e4 JD |
667 | /* |
668 | * Would be nice: | |
3a331a51 | 669 | * 1) Send showregs output to mconsole. |
3eddddcf JD |
670 | * 2) Add a way to stack dump all pids. |
671 | */ | |
672 | ||
3a331a51 | 673 | ptr += strlen("stack"); |
e7d2860b | 674 | ptr = skip_spaces(ptr); |
3eddddcf | 675 | |
ae2587e4 JD |
676 | /* |
677 | * Should really check for multiple pids or reject bad args here | |
678 | */ | |
3a331a51 | 679 | /* What do the arguments in mconsole_reply mean? */ |
ae2587e4 | 680 | if (sscanf(ptr, "%d", &pid_requested) == 0) { |
3a331a51 JD |
681 | mconsole_reply(req, "Please specify a pid", 1, 0); |
682 | return; | |
683 | } | |
3eddddcf | 684 | |
827b3f6a | 685 | to = find_task_by_pid_ns(pid_requested, &init_pid_ns); |
ae2587e4 | 686 | if ((to == NULL) || (pid_requested == 0)) { |
3a331a51 JD |
687 | mconsole_reply(req, "Couldn't find that pid", 1, 0); |
688 | return; | |
689 | } | |
6f517d3f | 690 | with_console(req, stack_proc, to); |
3eddddcf | 691 | } |
3eddddcf | 692 | |
ae2587e4 JD |
693 | /* |
694 | * Changed by mconsole_setup, which is __setup, and called before SMP is | |
1da177e4 LT |
695 | * active. |
696 | */ | |
d50084a2 | 697 | static char *notify_socket = NULL; |
1da177e4 | 698 | |
97a1fcbb | 699 | static int __init mconsole_init(void) |
1da177e4 LT |
700 | { |
701 | /* long to avoid size mismatch warnings from gcc */ | |
702 | long sock; | |
703 | int err; | |
36137120 | 704 | char file[UNIX_PATH_MAX]; |
1da177e4 | 705 | |
ae2587e4 JD |
706 | if (umid_file_name("mconsole", file, sizeof(file))) |
707 | return -1; | |
1da177e4 LT |
708 | snprintf(mconsole_socket_name, sizeof(file), "%s", file); |
709 | ||
710 | sock = os_create_unix_socket(file, sizeof(file), 1); | |
ae2587e4 JD |
711 | if (sock < 0) { |
712 | printk(KERN_ERR "Failed to initialize management console\n"); | |
713 | return 1; | |
1da177e4 | 714 | } |
438ee679 JD |
715 | if (os_set_fd_block(sock, 0)) |
716 | goto out; | |
1da177e4 LT |
717 | |
718 | register_reboot_notifier(&reboot_notifier); | |
719 | ||
720 | err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt, | |
aab94460 | 721 | IRQF_SHARED, "mconsole", (void *)sock); |
ae2587e4 JD |
722 | if (err) { |
723 | printk(KERN_ERR "Failed to get IRQ for management console\n"); | |
438ee679 | 724 | goto out; |
1da177e4 LT |
725 | } |
726 | ||
ae2587e4 | 727 | if (notify_socket != NULL) { |
970d6e3a | 728 | notify_socket = kstrdup(notify_socket, GFP_KERNEL); |
ae2587e4 | 729 | if (notify_socket != NULL) |
1da177e4 | 730 | mconsole_notify(notify_socket, MCONSOLE_SOCKET, |
d50084a2 | 731 | mconsole_socket_name, |
1da177e4 LT |
732 | strlen(mconsole_socket_name) + 1); |
733 | else printk(KERN_ERR "mconsole_setup failed to strdup " | |
734 | "string\n"); | |
735 | } | |
736 | ||
ae2587e4 | 737 | printk(KERN_INFO "mconsole (version %d) initialized on %s\n", |
1da177e4 | 738 | MCONSOLE_VERSION, mconsole_socket_name); |
ae2587e4 | 739 | return 0; |
438ee679 JD |
740 | |
741 | out: | |
742 | os_close_file(sock); | |
743 | return 1; | |
1da177e4 LT |
744 | } |
745 | ||
746 | __initcall(mconsole_init); | |
747 | ||
6613c5e8 AD |
748 | static ssize_t mconsole_proc_write(struct file *file, |
749 | const char __user *buffer, size_t count, loff_t *pos) | |
1da177e4 LT |
750 | { |
751 | char *buf; | |
752 | ||
753 | buf = kmalloc(count + 1, GFP_KERNEL); | |
ae2587e4 JD |
754 | if (buf == NULL) |
755 | return -ENOMEM; | |
1da177e4 | 756 | |
ae2587e4 | 757 | if (copy_from_user(buf, buffer, count)) { |
1da177e4 LT |
758 | count = -EFAULT; |
759 | goto out; | |
760 | } | |
761 | ||
762 | buf[count] = '\0'; | |
763 | ||
764 | mconsole_notify(notify_socket, MCONSOLE_USER_NOTIFY, buf, count); | |
765 | out: | |
766 | kfree(buf); | |
ae2587e4 | 767 | return count; |
1da177e4 LT |
768 | } |
769 | ||
6613c5e8 AD |
770 | static const struct file_operations mconsole_proc_fops = { |
771 | .owner = THIS_MODULE, | |
772 | .write = mconsole_proc_write, | |
6038f373 | 773 | .llseek = noop_llseek, |
6613c5e8 AD |
774 | }; |
775 | ||
1da177e4 LT |
776 | static int create_proc_mconsole(void) |
777 | { | |
778 | struct proc_dir_entry *ent; | |
779 | ||
ae2587e4 JD |
780 | if (notify_socket == NULL) |
781 | return 0; | |
1da177e4 | 782 | |
6613c5e8 | 783 | ent = proc_create("mconsole", 0200, NULL, &mconsole_proc_fops); |
ae2587e4 JD |
784 | if (ent == NULL) { |
785 | printk(KERN_INFO "create_proc_mconsole : create_proc_entry " | |
786 | "failed\n"); | |
787 | return 0; | |
1da177e4 | 788 | } |
ae2587e4 | 789 | return 0; |
1da177e4 LT |
790 | } |
791 | ||
792 | static DEFINE_SPINLOCK(notify_spinlock); | |
793 | ||
794 | void lock_notify(void) | |
795 | { | |
796 | spin_lock(¬ify_spinlock); | |
797 | } | |
798 | ||
799 | void unlock_notify(void) | |
800 | { | |
801 | spin_unlock(¬ify_spinlock); | |
802 | } | |
803 | ||
804 | __initcall(create_proc_mconsole); | |
805 | ||
088bec41 | 806 | #define NOTIFY "notify:" |
1da177e4 LT |
807 | |
808 | static int mconsole_setup(char *str) | |
809 | { | |
ae2587e4 | 810 | if (!strncmp(str, NOTIFY, strlen(NOTIFY))) { |
1da177e4 LT |
811 | str += strlen(NOTIFY); |
812 | notify_socket = str; | |
813 | } | |
814 | else printk(KERN_ERR "mconsole_setup : Unknown option - '%s'\n", str); | |
ae2587e4 | 815 | return 1; |
1da177e4 LT |
816 | } |
817 | ||
088bec41 | 818 | __setup("mconsole=", mconsole_setup); |
1da177e4 LT |
819 | |
820 | __uml_help(mconsole_setup, | |
821 | "mconsole=notify:<socket>\n" | |
822 | " Requests that the mconsole driver send a message to the named Unix\n" | |
823 | " socket containing the name of the mconsole socket. This also serves\n" | |
824 | " to notify outside processes when UML has booted far enough to respond\n" | |
825 | " to mconsole requests.\n\n" | |
826 | ); | |
827 | ||
828 | static int notify_panic(struct notifier_block *self, unsigned long unused1, | |
829 | void *ptr) | |
830 | { | |
831 | char *message = ptr; | |
832 | ||
ae2587e4 JD |
833 | if (notify_socket == NULL) |
834 | return 0; | |
1da177e4 | 835 | |
d50084a2 | 836 | mconsole_notify(notify_socket, MCONSOLE_PANIC, message, |
1da177e4 | 837 | strlen(message) + 1); |
ae2587e4 | 838 | return 0; |
1da177e4 LT |
839 | } |
840 | ||
841 | static struct notifier_block panic_exit_notifier = { | |
842 | .notifier_call = notify_panic, | |
843 | .next = NULL, | |
844 | .priority = 1 | |
845 | }; | |
846 | ||
847 | static int add_notifier(void) | |
848 | { | |
e041c683 AS |
849 | atomic_notifier_chain_register(&panic_notifier_list, |
850 | &panic_exit_notifier); | |
ae2587e4 | 851 | return 0; |
1da177e4 LT |
852 | } |
853 | ||
854 | __initcall(add_notifier); | |
855 | ||
856 | char *mconsole_notify_socket(void) | |
857 | { | |
ae2587e4 | 858 | return notify_socket; |
1da177e4 LT |
859 | } |
860 | ||
861 | EXPORT_SYMBOL(mconsole_notify_socket); |