mconsole_kern.c 21 KB

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