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Commit | Line | Data |
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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> | |
b17b0153 | 16 | #include <linux/sched/debug.h> |
827b3f6a JD |
17 | #include <linux/proc_fs.h> |
18 | #include <linux/slab.h> | |
19 | #include <linux/syscalls.h> | |
20 | #include <linux/utsname.h> | |
36137120 BS |
21 | #include <linux/socket.h> |
22 | #include <linux/un.h> | |
827b3f6a JD |
23 | #include <linux/workqueue.h> |
24 | #include <linux/mutex.h> | |
723a1d77 AV |
25 | #include <linux/fs.h> |
26 | #include <linux/mount.h> | |
27 | #include <linux/file.h> | |
7c0f6ba6 | 28 | #include <linux/uaccess.h> |
a3a85a76 | 29 | #include <asm/switch_to.h> |
827b3f6a | 30 | |
37185b33 AV |
31 | #include <init.h> |
32 | #include <irq_kern.h> | |
33 | #include <irq_user.h> | |
34 | #include <kern_util.h> | |
1da177e4 LT |
35 | #include "mconsole.h" |
36 | #include "mconsole_kern.h" | |
37185b33 | 37 | #include <os.h> |
1da177e4 | 38 | |
d50084a2 | 39 | static int do_unlink_socket(struct notifier_block *notifier, |
1da177e4 LT |
40 | unsigned long what, void *data) |
41 | { | |
ae2587e4 | 42 | return mconsole_unlink_socket(); |
1da177e4 LT |
43 | } |
44 | ||
45 | ||
46 | static struct notifier_block reboot_notifier = { | |
47 | .notifier_call = do_unlink_socket, | |
48 | .priority = 0, | |
49 | }; | |
50 | ||
d50084a2 | 51 | /* Safe without explicit locking for now. Tasklets provide their own |
1da177e4 LT |
52 | * locking, and the interrupt handler is safe because it can't interrupt |
53 | * itself and it can only happen on CPU 0. | |
54 | */ | |
55 | ||
9010772c | 56 | static LIST_HEAD(mc_requests); |
1da177e4 | 57 | |
6d5aefb8 | 58 | static void mc_work_proc(struct work_struct *unused) |
1da177e4 LT |
59 | { |
60 | struct mconsole_entry *req; | |
61 | unsigned long flags; | |
62 | ||
ae2587e4 | 63 | while (!list_empty(&mc_requests)) { |
dbdb4c06 | 64 | local_irq_save(flags); |
ae2587e4 | 65 | req = list_entry(mc_requests.next, struct mconsole_entry, list); |
1da177e4 LT |
66 | list_del(&req->list); |
67 | local_irq_restore(flags); | |
68 | req->request.cmd->handler(&req->request); | |
69 | kfree(req); | |
70 | } | |
71 | } | |
72 | ||
6d5aefb8 | 73 | static DECLARE_WORK(mconsole_work, mc_work_proc); |
1da177e4 | 74 | |
7bea96fd | 75 | static irqreturn_t mconsole_interrupt(int irq, void *dev_id) |
1da177e4 LT |
76 | { |
77 | /* long to avoid size mismatch warnings from gcc */ | |
78 | long fd; | |
79 | struct mconsole_entry *new; | |
3a51237d | 80 | static struct mc_request req; /* that's OK */ |
1da177e4 LT |
81 | |
82 | fd = (long) dev_id; | |
ae2587e4 JD |
83 | while (mconsole_get_request(fd, &req)) { |
84 | if (req.cmd->context == MCONSOLE_INTR) | |
1da177e4 LT |
85 | (*req.cmd->handler)(&req); |
86 | else { | |
60baa158 | 87 | new = kmalloc(sizeof(*new), GFP_NOWAIT); |
ae2587e4 | 88 | if (new == NULL) |
1da177e4 LT |
89 | mconsole_reply(&req, "Out of memory", 1, 0); |
90 | else { | |
91 | new->request = req; | |
3a51237d | 92 | new->request.regs = get_irq_regs()->regs; |
1da177e4 LT |
93 | list_add(&new->list, &mc_requests); |
94 | } | |
95 | } | |
96 | } | |
ae2587e4 | 97 | if (!list_empty(&mc_requests)) |
1da177e4 LT |
98 | schedule_work(&mconsole_work); |
99 | reactivate_fd(fd, MCONSOLE_IRQ); | |
ae2587e4 | 100 | return IRQ_HANDLED; |
1da177e4 LT |
101 | } |
102 | ||
103 | void mconsole_version(struct mc_request *req) | |
104 | { | |
105 | char version[256]; | |
106 | ||
e9ff3990 | 107 | sprintf(version, "%s %s %s %s %s", utsname()->sysname, |
ae2587e4 JD |
108 | utsname()->nodename, utsname()->release, utsname()->version, |
109 | utsname()->machine); | |
1da177e4 LT |
110 | mconsole_reply(req, version, 0, 0); |
111 | } | |
112 | ||
113 | void mconsole_log(struct mc_request *req) | |
114 | { | |
115 | int len; | |
116 | char *ptr = req->request.data; | |
117 | ||
118 | ptr += strlen("log "); | |
119 | ||
120 | len = req->len - (ptr - req->request.data); | |
ae2587e4 | 121 | printk(KERN_WARNING "%.*s", len, ptr); |
1da177e4 LT |
122 | mconsole_reply(req, "", 0, 0); |
123 | } | |
124 | ||
1da177e4 LT |
125 | void mconsole_proc(struct mc_request *req) |
126 | { | |
17cf22c3 | 127 | struct vfsmount *mnt = task_active_pid_ns(current)->proc_mnt; |
1da177e4 LT |
128 | char *buf; |
129 | int len; | |
723a1d77 | 130 | struct file *file; |
1da177e4 LT |
131 | int first_chunk = 1; |
132 | char *ptr = req->request.data; | |
133 | ||
134 | ptr += strlen("proc"); | |
e7d2860b | 135 | ptr = skip_spaces(ptr); |
1da177e4 | 136 | |
378c6520 | 137 | file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY, 0); |
723a1d77 | 138 | if (IS_ERR(file)) { |
1da177e4 | 139 | mconsole_reply(req, "Failed to open file", 1, 0); |
723a1d77 | 140 | printk(KERN_ERR "open /proc/%s: %ld\n", ptr, PTR_ERR(file)); |
1da177e4 LT |
141 | goto out; |
142 | } | |
143 | ||
144 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
ae2587e4 | 145 | if (buf == NULL) { |
1da177e4 | 146 | mconsole_reply(req, "Failed to allocate buffer", 1, 0); |
723a1d77 | 147 | goto out_fput; |
1da177e4 LT |
148 | } |
149 | ||
723a1d77 | 150 | do { |
c9036e9f | 151 | loff_t pos = file->f_pos; |
723a1d77 AV |
152 | mm_segment_t old_fs = get_fs(); |
153 | set_fs(KERNEL_DS); | |
154 | len = vfs_read(file, buf, PAGE_SIZE - 1, &pos); | |
155 | set_fs(old_fs); | |
156 | file->f_pos = pos; | |
1da177e4 LT |
157 | if (len < 0) { |
158 | mconsole_reply(req, "Read of file failed", 1, 0); | |
159 | goto out_free; | |
160 | } | |
ae2587e4 | 161 | /* Begin the file content on his own line. */ |
1da177e4 LT |
162 | if (first_chunk) { |
163 | mconsole_reply(req, "\n", 0, 1); | |
164 | first_chunk = 0; | |
165 | } | |
723a1d77 AV |
166 | buf[len] = '\0'; |
167 | mconsole_reply(req, buf, 0, (len > 0)); | |
168 | } while (len > 0); | |
1da177e4 LT |
169 | out_free: |
170 | kfree(buf); | |
723a1d77 AV |
171 | out_fput: |
172 | fput(file); | |
173 | out: ; | |
1da177e4 LT |
174 | } |
175 | ||
176 | #define UML_MCONSOLE_HELPTEXT \ | |
177 | "Commands: \n\ | |
178 | version - Get kernel version \n\ | |
179 | help - Print this message \n\ | |
180 | halt - Halt UML \n\ | |
181 | reboot - Reboot UML \n\ | |
182 | config <dev>=<config> - Add a new device to UML; \n\ | |
183 | same syntax as command line \n\ | |
184 | config <dev> - Query the configuration of a device \n\ | |
185 | remove <dev> - Remove a device from UML \n\ | |
186 | sysrq <letter> - Performs the SysRq action controlled by the letter \n\ | |
db805812 | 187 | cad - invoke the Ctrl-Alt-Del handler \n\ |
1da177e4 LT |
188 | stop - pause the UML; it will do nothing until it receives a 'go' \n\ |
189 | go - continue the UML after a 'stop' \n\ | |
190 | log <string> - make UML enter <string> into the kernel log\n\ | |
191 | proc <file> - returns the contents of the UML's /proc/<file>\n\ | |
3eddddcf | 192 | stack <pid> - returns the stack of the specified pid\n\ |
1da177e4 LT |
193 | " |
194 | ||
195 | void mconsole_help(struct mc_request *req) | |
196 | { | |
197 | mconsole_reply(req, UML_MCONSOLE_HELPTEXT, 0, 0); | |
198 | } | |
199 | ||
200 | void mconsole_halt(struct mc_request *req) | |
201 | { | |
202 | mconsole_reply(req, "", 0, 0); | |
203 | machine_halt(); | |
204 | } | |
205 | ||
206 | void mconsole_reboot(struct mc_request *req) | |
207 | { | |
208 | mconsole_reply(req, "", 0, 0); | |
209 | machine_restart(NULL); | |
210 | } | |
211 | ||
1da177e4 LT |
212 | void mconsole_cad(struct mc_request *req) |
213 | { | |
214 | mconsole_reply(req, "", 0, 0); | |
215 | ctrl_alt_del(); | |
216 | } | |
217 | ||
218 | void mconsole_go(struct mc_request *req) | |
219 | { | |
220 | mconsole_reply(req, "Not stopped", 1, 0); | |
221 | } | |
222 | ||
223 | void mconsole_stop(struct mc_request *req) | |
224 | { | |
225 | deactivate_fd(req->originating_fd, MCONSOLE_IRQ); | |
226 | os_set_fd_block(req->originating_fd, 1); | |
3a51237d | 227 | mconsole_reply(req, "stopped", 0, 0); |
cc0be0fb KS |
228 | for (;;) { |
229 | if (!mconsole_get_request(req->originating_fd, req)) | |
230 | continue; | |
3a51237d AV |
231 | if (req->cmd->handler == mconsole_go) |
232 | break; | |
233 | if (req->cmd->handler == mconsole_stop) { | |
234 | mconsole_reply(req, "Already stopped", 1, 0); | |
235 | continue; | |
236 | } | |
237 | if (req->cmd->handler == mconsole_sysrq) { | |
238 | struct pt_regs *old_regs; | |
239 | old_regs = set_irq_regs((struct pt_regs *)&req->regs); | |
240 | mconsole_sysrq(req); | |
241 | set_irq_regs(old_regs); | |
242 | continue; | |
243 | } | |
1da177e4 LT |
244 | (*req->cmd->handler)(req); |
245 | } | |
246 | os_set_fd_block(req->originating_fd, 0); | |
247 | reactivate_fd(req->originating_fd, MCONSOLE_IRQ); | |
248 | mconsole_reply(req, "", 0, 0); | |
249 | } | |
250 | ||
84f48d4f | 251 | static DEFINE_SPINLOCK(mc_devices_lock); |
42947cb9 | 252 | static LIST_HEAD(mconsole_devices); |
1da177e4 LT |
253 | |
254 | void mconsole_register_dev(struct mc_device *new) | |
255 | { | |
84f48d4f JD |
256 | spin_lock(&mc_devices_lock); |
257 | BUG_ON(!list_empty(&new->list)); | |
1da177e4 | 258 | list_add(&new->list, &mconsole_devices); |
84f48d4f | 259 | spin_unlock(&mc_devices_lock); |
1da177e4 LT |
260 | } |
261 | ||
262 | static struct mc_device *mconsole_find_dev(char *name) | |
263 | { | |
264 | struct list_head *ele; | |
265 | struct mc_device *dev; | |
266 | ||
ae2587e4 | 267 | list_for_each(ele, &mconsole_devices) { |
1da177e4 | 268 | dev = list_entry(ele, struct mc_device, list); |
ae2587e4 JD |
269 | if (!strncmp(name, dev->name, strlen(dev->name))) |
270 | return dev; | |
1da177e4 | 271 | } |
ae2587e4 | 272 | return NULL; |
1da177e4 LT |
273 | } |
274 | ||
02dea087 JD |
275 | #define UNPLUGGED_PER_PAGE \ |
276 | ((PAGE_SIZE - sizeof(struct list_head)) / sizeof(unsigned long)) | |
277 | ||
278 | struct unplugged_pages { | |
279 | struct list_head list; | |
280 | void *pages[UNPLUGGED_PER_PAGE]; | |
281 | }; | |
282 | ||
e98fa281 | 283 | static DEFINE_MUTEX(plug_mem_mutex); |
02dea087 | 284 | static unsigned long long unplugged_pages_count = 0; |
c59bce62 | 285 | static LIST_HEAD(unplugged_pages); |
02dea087 JD |
286 | static int unplug_index = UNPLUGGED_PER_PAGE; |
287 | ||
f28169d2 | 288 | static int mem_config(char *str, char **error_out) |
02dea087 JD |
289 | { |
290 | unsigned long long diff; | |
291 | int err = -EINVAL, i, add; | |
292 | char *ret; | |
293 | ||
ae2587e4 | 294 | if (str[0] != '=') { |
f28169d2 | 295 | *error_out = "Expected '=' after 'mem'"; |
02dea087 | 296 | goto out; |
f28169d2 | 297 | } |
02dea087 JD |
298 | |
299 | str++; | |
ae2587e4 | 300 | if (str[0] == '-') |
02dea087 | 301 | add = 0; |
ae2587e4 | 302 | else if (str[0] == '+') { |
02dea087 JD |
303 | add = 1; |
304 | } | |
f28169d2 JD |
305 | else { |
306 | *error_out = "Expected increment to start with '-' or '+'"; | |
307 | goto out; | |
308 | } | |
02dea087 JD |
309 | |
310 | str++; | |
311 | diff = memparse(str, &ret); | |
ae2587e4 | 312 | if (*ret != '\0') { |
f28169d2 | 313 | *error_out = "Failed to parse memory increment"; |
02dea087 | 314 | goto out; |
f28169d2 | 315 | } |
02dea087 JD |
316 | |
317 | diff /= PAGE_SIZE; | |
318 | ||
e98fa281 | 319 | mutex_lock(&plug_mem_mutex); |
ae2587e4 | 320 | for (i = 0; i < diff; i++) { |
02dea087 JD |
321 | struct unplugged_pages *unplugged; |
322 | void *addr; | |
323 | ||
ae2587e4 JD |
324 | if (add) { |
325 | if (list_empty(&unplugged_pages)) | |
02dea087 JD |
326 | break; |
327 | ||
328 | unplugged = list_entry(unplugged_pages.next, | |
329 | struct unplugged_pages, list); | |
ae2587e4 | 330 | if (unplug_index > 0) |
02dea087 JD |
331 | addr = unplugged->pages[--unplug_index]; |
332 | else { | |
333 | list_del(&unplugged->list); | |
334 | addr = unplugged; | |
335 | unplug_index = UNPLUGGED_PER_PAGE; | |
336 | } | |
337 | ||
338 | free_page((unsigned long) addr); | |
339 | unplugged_pages_count--; | |
340 | } | |
341 | else { | |
342 | struct page *page; | |
343 | ||
344 | page = alloc_page(GFP_ATOMIC); | |
ae2587e4 | 345 | if (page == NULL) |
02dea087 JD |
346 | break; |
347 | ||
348 | unplugged = page_address(page); | |
ae2587e4 | 349 | if (unplug_index == UNPLUGGED_PER_PAGE) { |
02dea087 JD |
350 | list_add(&unplugged->list, &unplugged_pages); |
351 | unplug_index = 0; | |
352 | } | |
353 | else { | |
354 | struct list_head *entry = unplugged_pages.next; | |
355 | addr = unplugged; | |
356 | ||
357 | unplugged = list_entry(entry, | |
358 | struct unplugged_pages, | |
359 | list); | |
02dea087 | 360 | err = os_drop_memory(addr, PAGE_SIZE); |
ae2587e4 JD |
361 | if (err) { |
362 | printk(KERN_ERR "Failed to release " | |
363 | "memory - errno = %d\n", err); | |
f28169d2 | 364 | *error_out = "Failed to release memory"; |
84f48d4f | 365 | goto out_unlock; |
f28169d2 JD |
366 | } |
367 | unplugged->pages[unplug_index++] = addr; | |
02dea087 JD |
368 | } |
369 | ||
370 | unplugged_pages_count++; | |
371 | } | |
372 | } | |
373 | ||
374 | err = 0; | |
84f48d4f | 375 | out_unlock: |
e98fa281 | 376 | mutex_unlock(&plug_mem_mutex); |
02dea087 JD |
377 | out: |
378 | return err; | |
379 | } | |
380 | ||
381 | static int mem_get_config(char *name, char *str, int size, char **error_out) | |
382 | { | |
383 | char buf[sizeof("18446744073709551615")]; | |
384 | int len = 0; | |
385 | ||
386 | sprintf(buf, "%ld", uml_physmem); | |
387 | CONFIG_CHUNK(str, size, len, buf, 1); | |
388 | ||
389 | return len; | |
390 | } | |
391 | ||
392 | static int mem_id(char **str, int *start_out, int *end_out) | |
393 | { | |
394 | *start_out = 0; | |
395 | *end_out = 0; | |
396 | ||
397 | return 0; | |
398 | } | |
399 | ||
f28169d2 | 400 | static int mem_remove(int n, char **error_out) |
02dea087 | 401 | { |
f28169d2 | 402 | *error_out = "Memory doesn't support the remove operation"; |
02dea087 JD |
403 | return -EBUSY; |
404 | } | |
405 | ||
406 | static struct mc_device mem_mc = { | |
84f48d4f | 407 | .list = LIST_HEAD_INIT(mem_mc.list), |
02dea087 JD |
408 | .name = "mem", |
409 | .config = mem_config, | |
410 | .get_config = mem_get_config, | |
411 | .id = mem_id, | |
412 | .remove = mem_remove, | |
413 | }; | |
414 | ||
97a1fcbb | 415 | static int __init mem_mc_init(void) |
02dea087 | 416 | { |
ae2587e4 | 417 | if (can_drop_memory()) |
02dea087 | 418 | mconsole_register_dev(&mem_mc); |
ae2587e4 JD |
419 | else printk(KERN_ERR "Can't release memory to the host - memory " |
420 | "hotplug won't be supported\n"); | |
02dea087 JD |
421 | return 0; |
422 | } | |
423 | ||
424 | __initcall(mem_mc_init); | |
425 | ||
1da177e4 LT |
426 | #define CONFIG_BUF_SIZE 64 |
427 | ||
d50084a2 | 428 | static void mconsole_get_config(int (*get_config)(char *, char *, int, |
1da177e4 LT |
429 | char **), |
430 | struct mc_request *req, char *name) | |
431 | { | |
432 | char default_buf[CONFIG_BUF_SIZE], *error, *buf; | |
433 | int n, size; | |
434 | ||
ae2587e4 | 435 | if (get_config == NULL) { |
1da177e4 LT |
436 | mconsole_reply(req, "No get_config routine defined", 1, 0); |
437 | return; | |
438 | } | |
439 | ||
440 | error = NULL; | |
91b165c0 | 441 | size = ARRAY_SIZE(default_buf); |
1da177e4 LT |
442 | buf = default_buf; |
443 | ||
ae2587e4 | 444 | while (1) { |
1da177e4 | 445 | n = (*get_config)(name, buf, size, &error); |
ae2587e4 | 446 | if (error != NULL) { |
1da177e4 LT |
447 | mconsole_reply(req, error, 1, 0); |
448 | goto out; | |
449 | } | |
450 | ||
ae2587e4 | 451 | if (n <= size) { |
1da177e4 LT |
452 | mconsole_reply(req, buf, 0, 0); |
453 | goto out; | |
454 | } | |
455 | ||
ae2587e4 | 456 | if (buf != default_buf) |
1da177e4 LT |
457 | kfree(buf); |
458 | ||
459 | size = n; | |
460 | buf = kmalloc(size, GFP_KERNEL); | |
ae2587e4 | 461 | if (buf == NULL) { |
1da177e4 LT |
462 | mconsole_reply(req, "Failed to allocate buffer", 1, 0); |
463 | return; | |
464 | } | |
465 | } | |
466 | out: | |
ae2587e4 | 467 | if (buf != default_buf) |
1da177e4 | 468 | kfree(buf); |
1da177e4 LT |
469 | } |
470 | ||
471 | void mconsole_config(struct mc_request *req) | |
472 | { | |
473 | struct mc_device *dev; | |
f28169d2 | 474 | char *ptr = req->request.data, *name, *error_string = ""; |
1da177e4 LT |
475 | int err; |
476 | ||
477 | ptr += strlen("config"); | |
e7d2860b | 478 | ptr = skip_spaces(ptr); |
1da177e4 | 479 | dev = mconsole_find_dev(ptr); |
ae2587e4 | 480 | if (dev == NULL) { |
1da177e4 LT |
481 | mconsole_reply(req, "Bad configuration option", 1, 0); |
482 | return; | |
483 | } | |
484 | ||
485 | name = &ptr[strlen(dev->name)]; | |
486 | ptr = name; | |
ae2587e4 | 487 | while ((*ptr != '=') && (*ptr != '\0')) |
1da177e4 LT |
488 | ptr++; |
489 | ||
ae2587e4 | 490 | if (*ptr == '=') { |
f28169d2 JD |
491 | err = (*dev->config)(name, &error_string); |
492 | mconsole_reply(req, error_string, err, 0); | |
1da177e4 LT |
493 | } |
494 | else mconsole_get_config(dev->get_config, req, name); | |
495 | } | |
496 | ||
497 | void mconsole_remove(struct mc_request *req) | |
498 | { | |
d50084a2 | 499 | struct mc_device *dev; |
29d56cfe | 500 | char *ptr = req->request.data, *err_msg = ""; |
3a331a51 | 501 | char error[256]; |
29d56cfe | 502 | int err, start, end, n; |
1da177e4 LT |
503 | |
504 | ptr += strlen("remove"); | |
e7d2860b | 505 | ptr = skip_spaces(ptr); |
1da177e4 | 506 | dev = mconsole_find_dev(ptr); |
ae2587e4 | 507 | if (dev == NULL) { |
1da177e4 LT |
508 | mconsole_reply(req, "Bad remove option", 1, 0); |
509 | return; | |
510 | } | |
29d56cfe | 511 | |
3a331a51 JD |
512 | ptr = &ptr[strlen(dev->name)]; |
513 | ||
514 | err = 1; | |
515 | n = (*dev->id)(&ptr, &start, &end); | |
ae2587e4 | 516 | if (n < 0) { |
3a331a51 JD |
517 | err_msg = "Couldn't parse device number"; |
518 | goto out; | |
519 | } | |
ae2587e4 | 520 | else if ((n < start) || (n > end)) { |
3a331a51 JD |
521 | sprintf(error, "Invalid device number - must be between " |
522 | "%d and %d", start, end); | |
523 | err_msg = error; | |
524 | goto out; | |
525 | } | |
29d56cfe | 526 | |
f28169d2 JD |
527 | err_msg = NULL; |
528 | err = (*dev->remove)(n, &err_msg); | |
ae2587e4 | 529 | switch(err) { |
d40f6d71 JD |
530 | case 0: |
531 | err_msg = ""; | |
532 | break; | |
3a331a51 | 533 | case -ENODEV: |
ae2587e4 | 534 | if (err_msg == NULL) |
f28169d2 | 535 | err_msg = "Device doesn't exist"; |
3a331a51 JD |
536 | break; |
537 | case -EBUSY: | |
ae2587e4 | 538 | if (err_msg == NULL) |
f28169d2 | 539 | err_msg = "Device is currently open"; |
3a331a51 JD |
540 | break; |
541 | default: | |
542 | break; | |
543 | } | |
544 | out: | |
29d56cfe | 545 | mconsole_reply(req, err_msg, err, 0); |
1da177e4 LT |
546 | } |
547 | ||
f92afe56 JD |
548 | struct mconsole_output { |
549 | struct list_head list; | |
550 | struct mc_request *req; | |
551 | }; | |
552 | ||
84f48d4f | 553 | static DEFINE_SPINLOCK(client_lock); |
6f517d3f JD |
554 | static LIST_HEAD(clients); |
555 | static char console_buf[MCONSOLE_MAX_DATA]; | |
6f517d3f JD |
556 | |
557 | static void console_write(struct console *console, const char *string, | |
54fa0ba4 | 558 | unsigned int len) |
6f517d3f JD |
559 | { |
560 | struct list_head *ele; | |
561 | int n; | |
562 | ||
ae2587e4 | 563 | if (list_empty(&clients)) |
6f517d3f JD |
564 | return; |
565 | ||
54fa0ba4 JD |
566 | while (len > 0) { |
567 | n = min((size_t) len, ARRAY_SIZE(console_buf)); | |
568 | strncpy(console_buf, string, n); | |
6f517d3f JD |
569 | string += n; |
570 | len -= n; | |
6f517d3f | 571 | |
ae2587e4 | 572 | list_for_each(ele, &clients) { |
f92afe56 | 573 | struct mconsole_output *entry; |
6f517d3f | 574 | |
f92afe56 | 575 | entry = list_entry(ele, struct mconsole_output, list); |
54fa0ba4 | 576 | mconsole_reply_len(entry->req, console_buf, n, 0, 1); |
6f517d3f | 577 | } |
6f517d3f JD |
578 | } |
579 | } | |
580 | ||
581 | static struct console mc_console = { .name = "mc", | |
582 | .write = console_write, | |
a174b30e | 583 | .flags = CON_ENABLED, |
6f517d3f JD |
584 | .index = -1 }; |
585 | ||
586 | static int mc_add_console(void) | |
587 | { | |
588 | register_console(&mc_console); | |
589 | return 0; | |
590 | } | |
591 | ||
592 | late_initcall(mc_add_console); | |
593 | ||
594 | static void with_console(struct mc_request *req, void (*proc)(void *), | |
595 | void *arg) | |
596 | { | |
f92afe56 | 597 | struct mconsole_output entry; |
6f517d3f JD |
598 | unsigned long flags; |
599 | ||
f92afe56 | 600 | entry.req = req; |
84f48d4f | 601 | spin_lock_irqsave(&client_lock, flags); |
6f517d3f | 602 | list_add(&entry.list, &clients); |
84f48d4f | 603 | spin_unlock_irqrestore(&client_lock, flags); |
6f517d3f JD |
604 | |
605 | (*proc)(arg); | |
606 | ||
54fa0ba4 | 607 | mconsole_reply_len(req, "", 0, 0, 0); |
6f517d3f | 608 | |
84f48d4f | 609 | spin_lock_irqsave(&client_lock, flags); |
6f517d3f | 610 | list_del(&entry.list); |
84f48d4f | 611 | spin_unlock_irqrestore(&client_lock, flags); |
6f517d3f JD |
612 | } |
613 | ||
4111b025 | 614 | #ifdef CONFIG_MAGIC_SYSRQ |
54fa0ba4 JD |
615 | |
616 | #include <linux/sysrq.h> | |
617 | ||
4111b025 JD |
618 | static void sysrq_proc(void *arg) |
619 | { | |
620 | char *op = arg; | |
f335397d | 621 | handle_sysrq(*op); |
4111b025 JD |
622 | } |
623 | ||
624 | void mconsole_sysrq(struct mc_request *req) | |
625 | { | |
626 | char *ptr = req->request.data; | |
627 | ||
628 | ptr += strlen("sysrq"); | |
e7d2860b | 629 | ptr = skip_spaces(ptr); |
4111b025 | 630 | |
ae2587e4 JD |
631 | /* |
632 | * With 'b', the system will shut down without a chance to reply, | |
4111b025 JD |
633 | * so in this case, we reply first. |
634 | */ | |
ae2587e4 | 635 | if (*ptr == 'b') |
4111b025 JD |
636 | mconsole_reply(req, "", 0, 0); |
637 | ||
638 | with_console(req, sysrq_proc, ptr); | |
639 | } | |
640 | #else | |
641 | void mconsole_sysrq(struct mc_request *req) | |
642 | { | |
643 | mconsole_reply(req, "Sysrq not compiled in", 1, 0); | |
644 | } | |
645 | #endif | |
646 | ||
6f517d3f JD |
647 | static void stack_proc(void *arg) |
648 | { | |
a1850e9c | 649 | struct task_struct *task = arg; |
6f517d3f | 650 | |
a1850e9c | 651 | show_stack(task, NULL); |
6f517d3f JD |
652 | } |
653 | ||
ae2587e4 JD |
654 | /* |
655 | * Mconsole stack trace | |
3eddddcf JD |
656 | * Added by Allan Graves, Jeff Dike |
657 | * Dumps a stacks registers to the linux console. | |
658 | * Usage stack <pid>. | |
659 | */ | |
42fda663 | 660 | void mconsole_stack(struct mc_request *req) |
3eddddcf | 661 | { |
3a331a51 JD |
662 | char *ptr = req->request.data; |
663 | int pid_requested= -1; | |
3eddddcf JD |
664 | struct task_struct *to = NULL; |
665 | ||
ae2587e4 JD |
666 | /* |
667 | * Would be nice: | |
3a331a51 | 668 | * 1) Send showregs output to mconsole. |
3eddddcf JD |
669 | * 2) Add a way to stack dump all pids. |
670 | */ | |
671 | ||
3a331a51 | 672 | ptr += strlen("stack"); |
e7d2860b | 673 | ptr = skip_spaces(ptr); |
3eddddcf | 674 | |
ae2587e4 JD |
675 | /* |
676 | * Should really check for multiple pids or reject bad args here | |
677 | */ | |
3a331a51 | 678 | /* What do the arguments in mconsole_reply mean? */ |
ae2587e4 | 679 | if (sscanf(ptr, "%d", &pid_requested) == 0) { |
3a331a51 JD |
680 | mconsole_reply(req, "Please specify a pid", 1, 0); |
681 | return; | |
682 | } | |
3eddddcf | 683 | |
827b3f6a | 684 | to = find_task_by_pid_ns(pid_requested, &init_pid_ns); |
ae2587e4 | 685 | if ((to == NULL) || (pid_requested == 0)) { |
3a331a51 JD |
686 | mconsole_reply(req, "Couldn't find that pid", 1, 0); |
687 | return; | |
688 | } | |
6f517d3f | 689 | with_console(req, stack_proc, to); |
3eddddcf | 690 | } |
3eddddcf | 691 | |
ae2587e4 JD |
692 | /* |
693 | * Changed by mconsole_setup, which is __setup, and called before SMP is | |
1da177e4 LT |
694 | * active. |
695 | */ | |
d50084a2 | 696 | static char *notify_socket = NULL; |
1da177e4 | 697 | |
97a1fcbb | 698 | static int __init mconsole_init(void) |
1da177e4 LT |
699 | { |
700 | /* long to avoid size mismatch warnings from gcc */ | |
701 | long sock; | |
702 | int err; | |
36137120 | 703 | char file[UNIX_PATH_MAX]; |
1da177e4 | 704 | |
ae2587e4 JD |
705 | if (umid_file_name("mconsole", file, sizeof(file))) |
706 | return -1; | |
1da177e4 LT |
707 | snprintf(mconsole_socket_name, sizeof(file), "%s", file); |
708 | ||
709 | sock = os_create_unix_socket(file, sizeof(file), 1); | |
ae2587e4 JD |
710 | if (sock < 0) { |
711 | printk(KERN_ERR "Failed to initialize management console\n"); | |
712 | return 1; | |
1da177e4 | 713 | } |
438ee679 JD |
714 | if (os_set_fd_block(sock, 0)) |
715 | goto out; | |
1da177e4 LT |
716 | |
717 | register_reboot_notifier(&reboot_notifier); | |
718 | ||
719 | err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt, | |
aab94460 | 720 | IRQF_SHARED, "mconsole", (void *)sock); |
ae2587e4 JD |
721 | if (err) { |
722 | printk(KERN_ERR "Failed to get IRQ for management console\n"); | |
438ee679 | 723 | goto out; |
1da177e4 LT |
724 | } |
725 | ||
ae2587e4 | 726 | if (notify_socket != NULL) { |
970d6e3a | 727 | notify_socket = kstrdup(notify_socket, GFP_KERNEL); |
ae2587e4 | 728 | if (notify_socket != NULL) |
1da177e4 | 729 | mconsole_notify(notify_socket, MCONSOLE_SOCKET, |
d50084a2 | 730 | mconsole_socket_name, |
1da177e4 LT |
731 | strlen(mconsole_socket_name) + 1); |
732 | else printk(KERN_ERR "mconsole_setup failed to strdup " | |
733 | "string\n"); | |
734 | } | |
735 | ||
ae2587e4 | 736 | printk(KERN_INFO "mconsole (version %d) initialized on %s\n", |
1da177e4 | 737 | MCONSOLE_VERSION, mconsole_socket_name); |
ae2587e4 | 738 | return 0; |
438ee679 JD |
739 | |
740 | out: | |
741 | os_close_file(sock); | |
742 | return 1; | |
1da177e4 LT |
743 | } |
744 | ||
745 | __initcall(mconsole_init); | |
746 | ||
6613c5e8 AD |
747 | static ssize_t mconsole_proc_write(struct file *file, |
748 | const char __user *buffer, size_t count, loff_t *pos) | |
1da177e4 LT |
749 | { |
750 | char *buf; | |
751 | ||
793b796e AV |
752 | buf = memdup_user_nul(buffer, count); |
753 | if (IS_ERR(buf)) | |
754 | return PTR_ERR(buf); | |
1da177e4 LT |
755 | |
756 | mconsole_notify(notify_socket, MCONSOLE_USER_NOTIFY, buf, count); | |
1da177e4 | 757 | kfree(buf); |
ae2587e4 | 758 | return count; |
1da177e4 LT |
759 | } |
760 | ||
6613c5e8 AD |
761 | static const struct file_operations mconsole_proc_fops = { |
762 | .owner = THIS_MODULE, | |
763 | .write = mconsole_proc_write, | |
6038f373 | 764 | .llseek = noop_llseek, |
6613c5e8 AD |
765 | }; |
766 | ||
1da177e4 LT |
767 | static int create_proc_mconsole(void) |
768 | { | |
769 | struct proc_dir_entry *ent; | |
770 | ||
ae2587e4 JD |
771 | if (notify_socket == NULL) |
772 | return 0; | |
1da177e4 | 773 | |
6613c5e8 | 774 | ent = proc_create("mconsole", 0200, NULL, &mconsole_proc_fops); |
ae2587e4 | 775 | if (ent == NULL) { |
4554eb90 | 776 | printk(KERN_INFO "create_proc_mconsole : proc_create failed\n"); |
ae2587e4 | 777 | return 0; |
1da177e4 | 778 | } |
ae2587e4 | 779 | return 0; |
1da177e4 LT |
780 | } |
781 | ||
782 | static DEFINE_SPINLOCK(notify_spinlock); | |
783 | ||
784 | void lock_notify(void) | |
785 | { | |
786 | spin_lock(¬ify_spinlock); | |
787 | } | |
788 | ||
789 | void unlock_notify(void) | |
790 | { | |
791 | spin_unlock(¬ify_spinlock); | |
792 | } | |
793 | ||
794 | __initcall(create_proc_mconsole); | |
795 | ||
088bec41 | 796 | #define NOTIFY "notify:" |
1da177e4 LT |
797 | |
798 | static int mconsole_setup(char *str) | |
799 | { | |
ae2587e4 | 800 | if (!strncmp(str, NOTIFY, strlen(NOTIFY))) { |
1da177e4 LT |
801 | str += strlen(NOTIFY); |
802 | notify_socket = str; | |
803 | } | |
804 | else printk(KERN_ERR "mconsole_setup : Unknown option - '%s'\n", str); | |
ae2587e4 | 805 | return 1; |
1da177e4 LT |
806 | } |
807 | ||
088bec41 | 808 | __setup("mconsole=", mconsole_setup); |
1da177e4 LT |
809 | |
810 | __uml_help(mconsole_setup, | |
811 | "mconsole=notify:<socket>\n" | |
812 | " Requests that the mconsole driver send a message to the named Unix\n" | |
813 | " socket containing the name of the mconsole socket. This also serves\n" | |
814 | " to notify outside processes when UML has booted far enough to respond\n" | |
815 | " to mconsole requests.\n\n" | |
816 | ); | |
817 | ||
818 | static int notify_panic(struct notifier_block *self, unsigned long unused1, | |
819 | void *ptr) | |
820 | { | |
821 | char *message = ptr; | |
822 | ||
ae2587e4 JD |
823 | if (notify_socket == NULL) |
824 | return 0; | |
1da177e4 | 825 | |
d50084a2 | 826 | mconsole_notify(notify_socket, MCONSOLE_PANIC, message, |
1da177e4 | 827 | strlen(message) + 1); |
ae2587e4 | 828 | return 0; |
1da177e4 LT |
829 | } |
830 | ||
831 | static struct notifier_block panic_exit_notifier = { | |
832 | .notifier_call = notify_panic, | |
833 | .next = NULL, | |
834 | .priority = 1 | |
835 | }; | |
836 | ||
837 | static int add_notifier(void) | |
838 | { | |
e041c683 AS |
839 | atomic_notifier_chain_register(&panic_notifier_list, |
840 | &panic_exit_notifier); | |
ae2587e4 | 841 | return 0; |
1da177e4 LT |
842 | } |
843 | ||
844 | __initcall(add_notifier); | |
845 | ||
846 | char *mconsole_notify_socket(void) | |
847 | { | |
ae2587e4 | 848 | return notify_socket; |
1da177e4 LT |
849 | } |
850 | ||
851 | EXPORT_SYMBOL(mconsole_notify_socket); |