2 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org)
3 * Copyright (C) 2001 - 2003 Jeff Dike (jdike@addtoit.com)
4 * Licensed under the GPL
7 #include "linux/kernel.h"
8 #include "linux/slab.h"
9 #include "linux/init.h"
10 #include "linux/notifier.h"
11 #include "linux/reboot.h"
12 #include "linux/utsname.h"
13 #include "linux/ctype.h"
14 #include "linux/interrupt.h"
15 #include "linux/sysrq.h"
16 #include "linux/workqueue.h"
17 #include "linux/module.h"
18 #include "linux/file.h"
20 #include "linux/namei.h"
21 #include "linux/proc_fs.h"
22 #include "linux/syscalls.h"
24 #include "asm/uaccess.h"
25 #include "user_util.h"
26 #include "kern_util.h"
29 #include "mconsole_kern.h"
36 static int do_unlink_socket(struct notifier_block
*notifier
,
37 unsigned long what
, void *data
)
39 return(mconsole_unlink_socket());
43 static struct notifier_block reboot_notifier
= {
44 .notifier_call
= do_unlink_socket
,
48 /* Safe without explicit locking for now. Tasklets provide their own
49 * locking, and the interrupt handler is safe because it can't interrupt
50 * itself and it can only happen on CPU 0.
53 LIST_HEAD(mc_requests
);
55 static void mc_work_proc(void *unused
)
57 struct mconsole_entry
*req
;
60 while(!list_empty(&mc_requests
)){
61 local_save_flags(flags
);
62 req
= list_entry(mc_requests
.next
, struct mconsole_entry
,
65 local_irq_restore(flags
);
66 req
->request
.cmd
->handler(&req
->request
);
71 DECLARE_WORK(mconsole_work
, mc_work_proc
, NULL
);
73 static irqreturn_t
mconsole_interrupt(int irq
, void *dev_id
,
76 /* long to avoid size mismatch warnings from gcc */
78 struct mconsole_entry
*new;
79 struct mc_request req
;
82 while (mconsole_get_request(fd
, &req
)){
83 if(req
.cmd
->context
== MCONSOLE_INTR
)
84 (*req
.cmd
->handler
)(&req
);
86 new = kmalloc(sizeof(*new), GFP_ATOMIC
);
88 mconsole_reply(&req
, "Out of memory", 1, 0);
91 list_add(&new->list
, &mc_requests
);
95 if(!list_empty(&mc_requests
))
96 schedule_work(&mconsole_work
);
97 reactivate_fd(fd
, MCONSOLE_IRQ
);
101 void mconsole_version(struct mc_request
*req
)
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);
111 void mconsole_log(struct mc_request
*req
)
114 char *ptr
= req
->request
.data
;
116 ptr
+= strlen("log ");
118 len
= req
->len
- (ptr
- req
->request
.data
);
119 printk("%.*s", len
, ptr
);
120 mconsole_reply(req
, "", 0, 0);
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.*/
128 void mconsole_proc(struct mc_request
*req
)
131 struct file_system_type
*proc
;
132 struct super_block
*super
;
135 char *ptr
= req
->request
.data
, *buf
;
137 ptr
+= strlen("proc");
138 while(isspace(*ptr
)) ptr
++;
140 proc
= get_fs_type("proc");
142 mconsole_reply(req
, "procfs not registered", 1, 0);
146 super
= (*proc
->get_sb
)(proc
, 0, NULL
, NULL
);
147 put_filesystem(proc
);
149 mconsole_reply(req
, "Failed to get procfs superblock", 1, 0);
152 up_write(&super
->s_umount
);
154 nd
.dentry
= super
->s_root
;
156 nd
.flags
= O_RDONLY
+ 1;
157 nd
.last_type
= LAST_ROOT
;
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
);
164 mconsole_reply(req
, "Failed to look up file", 1, 0);
168 file
= dentry_open(nd
.dentry
, nd
.mnt
, O_RDONLY
);
170 mconsole_reply(req
, "Failed to open file", 1, 0);
175 buf
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
177 mconsole_reply(req
, "Failed to allocate buffer", 1, 0);
181 if((file
->f_op
!= NULL
) && (file
->f_op
->read
!= NULL
)){
183 n
= (*file
->f_op
->read
)(file
, buf
, PAGE_SIZE
- 1,
187 mconsole_reply(req
, buf
, 0, (n
> 0));
190 mconsole_reply(req
, "Read of file failed",
196 else mconsole_reply(req
, "", 0, 0);
203 deactivate_super(super
);
208 void mconsole_proc(struct mc_request
*req
)
215 char *ptr
= req
->request
.data
;
217 ptr
+= strlen("proc");
218 while(isspace(*ptr
)) ptr
++;
219 snprintf(path
, sizeof(path
), "/proc/%s", ptr
);
221 fd
= sys_open(path
, 0, 0);
223 mconsole_reply(req
, "Failed to open file", 1, 0);
224 printk("open %s: %d\n",path
,fd
);
228 buf
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
230 mconsole_reply(req
, "Failed to allocate buffer", 1, 0);
235 len
= sys_read(fd
, buf
, PAGE_SIZE
-1);
237 mconsole_reply(req
, "Read of file failed", 1, 0);
240 /*Begin the file content on his own line.*/
242 mconsole_reply(req
, "\n", 0, 1);
245 if (len
== PAGE_SIZE
-1) {
247 mconsole_reply(req
, buf
, 0, 1);
250 mconsole_reply(req
, buf
, 0, 0);
263 #define UML_MCONSOLE_HELPTEXT \
265 version - Get kernel version \n\
266 help - Print this message \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\
281 void mconsole_help(struct mc_request
*req
)
283 mconsole_reply(req
, UML_MCONSOLE_HELPTEXT
, 0, 0);
286 void mconsole_halt(struct mc_request
*req
)
288 mconsole_reply(req
, "", 0, 0);
292 void mconsole_reboot(struct mc_request
*req
)
294 mconsole_reply(req
, "", 0, 0);
295 machine_restart(NULL
);
298 extern void ctrl_alt_del(void);
300 void mconsole_cad(struct mc_request
*req
)
302 mconsole_reply(req
, "", 0, 0);
306 void mconsole_go(struct mc_request
*req
)
308 mconsole_reply(req
, "Not stopped", 1, 0);
311 void mconsole_stop(struct mc_request
*req
)
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
);
320 os_set_fd_block(req
->originating_fd
, 0);
321 reactivate_fd(req
->originating_fd
, MCONSOLE_IRQ
);
322 mconsole_reply(req
, "", 0, 0);
325 /* This list is populated by __initcall routines. */
327 LIST_HEAD(mconsole_devices
);
329 void mconsole_register_dev(struct mc_device
*new)
331 list_add(&new->list
, &mconsole_devices
);
334 static struct mc_device
*mconsole_find_dev(char *name
)
336 struct list_head
*ele
;
337 struct mc_device
*dev
;
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
)))
347 #define CONFIG_BUF_SIZE 64
349 static void mconsole_get_config(int (*get_config
)(char *, char *, int,
351 struct mc_request
*req
, char *name
)
353 char default_buf
[CONFIG_BUF_SIZE
], *error
, *buf
;
356 if(get_config
== NULL
){
357 mconsole_reply(req
, "No get_config routine defined", 1, 0);
362 size
= sizeof(default_buf
)/sizeof(default_buf
[0]);
366 n
= (*get_config
)(name
, buf
, size
, &error
);
368 mconsole_reply(req
, error
, 1, 0);
373 mconsole_reply(req
, buf
, 0, 0);
377 if(buf
!= default_buf
)
381 buf
= kmalloc(size
, GFP_KERNEL
);
383 mconsole_reply(req
, "Failed to allocate buffer", 1, 0);
388 if(buf
!= default_buf
)
393 void mconsole_config(struct mc_request
*req
)
395 struct mc_device
*dev
;
396 char *ptr
= req
->request
.data
, *name
;
399 ptr
+= strlen("config");
400 while(isspace(*ptr
)) ptr
++;
401 dev
= mconsole_find_dev(ptr
);
403 mconsole_reply(req
, "Bad configuration option", 1, 0);
407 name
= &ptr
[strlen(dev
->name
)];
409 while((*ptr
!= '=') && (*ptr
!= '\0'))
413 err
= (*dev
->config
)(name
);
414 mconsole_reply(req
, "", err
, 0);
416 else mconsole_get_config(dev
->get_config
, req
, name
);
419 void mconsole_remove(struct mc_request
*req
)
421 struct mc_device
*dev
;
422 char *ptr
= req
->request
.data
, *err_msg
= "";
424 int err
, start
, end
, n
;
426 ptr
+= strlen("remove");
427 while(isspace(*ptr
)) ptr
++;
428 dev
= mconsole_find_dev(ptr
);
430 mconsole_reply(req
, "Bad remove option", 1, 0);
434 ptr
= &ptr
[strlen(dev
->name
)];
437 n
= (*dev
->id
)(&ptr
, &start
, &end
);
439 err_msg
= "Couldn't parse device number";
442 else if((n
< start
) || (n
> end
)){
443 sprintf(error
, "Invalid device number - must be between "
444 "%d and %d", start
, end
);
449 err
= (*dev
->remove
)(n
);
452 err_msg
= "Device doesn't exist";
455 err_msg
= "Device is currently open";
461 mconsole_reply(req
, err_msg
, err
, 0);
464 #ifdef CONFIG_MAGIC_SYSRQ
465 void mconsole_sysrq(struct mc_request
*req
)
467 char *ptr
= req
->request
.data
;
469 ptr
+= strlen("sysrq");
470 while(isspace(*ptr
)) ptr
++;
472 mconsole_reply(req
, "", 0, 0);
473 handle_sysrq(*ptr
, ¤t
->thread
.regs
, NULL
);
476 void mconsole_sysrq(struct mc_request
*req
)
478 mconsole_reply(req
, "Sysrq not compiled in", 1, 0);
482 /* Changed by mconsole_setup, which is __setup, and called before SMP is
485 static char *notify_socket
= NULL
;
487 int mconsole_init(void)
489 /* long to avoid size mismatch warnings from gcc */
494 if(umid_file_name("mconsole", file
, sizeof(file
))) return(-1);
495 snprintf(mconsole_socket_name
, sizeof(file
), "%s", file
);
497 sock
= os_create_unix_socket(file
, sizeof(file
), 1);
499 printk("Failed to initialize management console\n");
503 register_reboot_notifier(&reboot_notifier
);
505 err
= um_request_irq(MCONSOLE_IRQ
, sock
, IRQ_READ
, mconsole_interrupt
,
506 SA_INTERRUPT
| SA_SHIRQ
| SA_SAMPLE_RANDOM
,
507 "mconsole", (void *)sock
);
509 printk("Failed to get IRQ for management console\n");
513 if(notify_socket
!= NULL
){
514 notify_socket
= uml_strdup(notify_socket
);
515 if(notify_socket
!= NULL
)
516 mconsole_notify(notify_socket
, MCONSOLE_SOCKET
,
517 mconsole_socket_name
,
518 strlen(mconsole_socket_name
) + 1);
519 else printk(KERN_ERR
"mconsole_setup failed to strdup "
523 printk("mconsole (version %d) initialized on %s\n",
524 MCONSOLE_VERSION
, mconsole_socket_name
);
528 __initcall(mconsole_init
);
530 static int write_proc_mconsole(struct file
*file
, const char __user
*buffer
,
531 unsigned long count
, void *data
)
535 buf
= kmalloc(count
+ 1, GFP_KERNEL
);
539 if(copy_from_user(buf
, buffer
, count
)){
546 mconsole_notify(notify_socket
, MCONSOLE_USER_NOTIFY
, buf
, count
);
552 static int create_proc_mconsole(void)
554 struct proc_dir_entry
*ent
;
556 if(notify_socket
== NULL
) return(0);
558 ent
= create_proc_entry("mconsole", S_IFREG
| 0200, NULL
);
560 printk("create_proc_mconsole : create_proc_entry failed\n");
564 ent
->read_proc
= NULL
;
565 ent
->write_proc
= write_proc_mconsole
;
569 static DEFINE_SPINLOCK(notify_spinlock
);
571 void lock_notify(void)
573 spin_lock(¬ify_spinlock
);
576 void unlock_notify(void)
578 spin_unlock(¬ify_spinlock
);
581 __initcall(create_proc_mconsole
);
583 #define NOTIFY "=notify:"
585 static int mconsole_setup(char *str
)
587 if(!strncmp(str
, NOTIFY
, strlen(NOTIFY
))){
588 str
+= strlen(NOTIFY
);
591 else printk(KERN_ERR
"mconsole_setup : Unknown option - '%s'\n", str
);
595 __setup("mconsole", mconsole_setup
);
597 __uml_help(mconsole_setup
,
598 "mconsole=notify:<socket>\n"
599 " Requests that the mconsole driver send a message to the named Unix\n"
600 " socket containing the name of the mconsole socket. This also serves\n"
601 " to notify outside processes when UML has booted far enough to respond\n"
602 " to mconsole requests.\n\n"
605 static int notify_panic(struct notifier_block
*self
, unsigned long unused1
,
610 if(notify_socket
== NULL
) return(0);
612 mconsole_notify(notify_socket
, MCONSOLE_PANIC
, message
,
613 strlen(message
) + 1);
617 static struct notifier_block panic_exit_notifier
= {
618 .notifier_call
= notify_panic
,
623 static int add_notifier(void)
625 notifier_chain_register(&panic_notifier_list
, &panic_exit_notifier
);
629 __initcall(add_notifier
);
631 char *mconsole_notify_socket(void)
633 return(notify_socket
);
636 EXPORT_SYMBOL(mconsole_notify_socket
);
639 * Overrides for Emacs so that we follow Linus's tabbing style.
640 * Emacs will notice this stuff at the end of the file and automatically
641 * adjust the settings for this buffer only. This must remain at the end
643 * ---------------------------------------------------------------------------
645 * c-file-style: "linux"