| /* |
| * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) |
| * Copyright (C) 2001 - 2003 Jeff Dike (jdike@addtoit.com) |
| * Licensed under the GPL |
| */ |
| |
| #include "linux/kernel.h" |
| #include "linux/slab.h" |
| #include "linux/init.h" |
| #include "linux/notifier.h" |
| #include "linux/reboot.h" |
| #include "linux/utsname.h" |
| #include "linux/ctype.h" |
| #include "linux/interrupt.h" |
| #include "linux/sysrq.h" |
| #include "linux/workqueue.h" |
| #include "linux/module.h" |
| #include "linux/file.h" |
| #include "linux/fs.h" |
| #include "linux/namei.h" |
| #include "linux/proc_fs.h" |
| #include "linux/syscalls.h" |
| #include "asm/irq.h" |
| #include "asm/uaccess.h" |
| #include "user_util.h" |
| #include "kern_util.h" |
| #include "kern.h" |
| #include "mconsole.h" |
| #include "mconsole_kern.h" |
| #include "irq_user.h" |
| #include "init.h" |
| #include "os.h" |
| #include "umid.h" |
| #include "irq_kern.h" |
| #include "choose-mode.h" |
| |
| static int do_unlink_socket(struct notifier_block *notifier, |
| unsigned long what, void *data) |
| { |
| return(mconsole_unlink_socket()); |
| } |
| |
| |
| static struct notifier_block reboot_notifier = { |
| .notifier_call = do_unlink_socket, |
| .priority = 0, |
| }; |
| |
| /* Safe without explicit locking for now. Tasklets provide their own |
| * locking, and the interrupt handler is safe because it can't interrupt |
| * itself and it can only happen on CPU 0. |
| */ |
| |
| LIST_HEAD(mc_requests); |
| |
| static void mc_work_proc(void *unused) |
| { |
| struct mconsole_entry *req; |
| unsigned long flags; |
| |
| while(!list_empty(&mc_requests)){ |
| local_save_flags(flags); |
| req = list_entry(mc_requests.next, struct mconsole_entry, |
| list); |
| list_del(&req->list); |
| local_irq_restore(flags); |
| req->request.cmd->handler(&req->request); |
| kfree(req); |
| } |
| } |
| |
| DECLARE_WORK(mconsole_work, mc_work_proc, NULL); |
| |
| static irqreturn_t mconsole_interrupt(int irq, void *dev_id, |
| struct pt_regs *regs) |
| { |
| /* long to avoid size mismatch warnings from gcc */ |
| long fd; |
| struct mconsole_entry *new; |
| struct mc_request req; |
| |
| fd = (long) dev_id; |
| while (mconsole_get_request(fd, &req)){ |
| if(req.cmd->context == MCONSOLE_INTR) |
| (*req.cmd->handler)(&req); |
| else { |
| new = kmalloc(sizeof(*new), GFP_ATOMIC); |
| if(new == NULL) |
| mconsole_reply(&req, "Out of memory", 1, 0); |
| else { |
| new->request = req; |
| list_add(&new->list, &mc_requests); |
| } |
| } |
| } |
| if(!list_empty(&mc_requests)) |
| schedule_work(&mconsole_work); |
| reactivate_fd(fd, MCONSOLE_IRQ); |
| return(IRQ_HANDLED); |
| } |
| |
| void mconsole_version(struct mc_request *req) |
| { |
| char version[256]; |
| |
| sprintf(version, "%s %s %s %s %s", system_utsname.sysname, |
| system_utsname.nodename, system_utsname.release, |
| system_utsname.version, system_utsname.machine); |
| mconsole_reply(req, version, 0, 0); |
| } |
| |
| void mconsole_log(struct mc_request *req) |
| { |
| int len; |
| char *ptr = req->request.data; |
| |
| ptr += strlen("log "); |
| |
| len = req->len - (ptr - req->request.data); |
| printk("%.*s", len, ptr); |
| mconsole_reply(req, "", 0, 0); |
| } |
| |
| /* This is a more convoluted version of mconsole_proc, which has some stability |
| * problems; however, we need it fixed, because it is expected that UML users |
| * mount HPPFS instead of procfs on /proc. And we want mconsole_proc to still |
| * show the real procfs content, not the ones from hppfs.*/ |
| #if 0 |
| void mconsole_proc(struct mc_request *req) |
| { |
| struct nameidata nd; |
| struct file_system_type *proc; |
| struct super_block *super; |
| struct file *file; |
| int n, err; |
| char *ptr = req->request.data, *buf; |
| |
| ptr += strlen("proc"); |
| while(isspace(*ptr)) ptr++; |
| |
| proc = get_fs_type("proc"); |
| if(proc == NULL){ |
| mconsole_reply(req, "procfs not registered", 1, 0); |
| goto out; |
| } |
| |
| super = (*proc->get_sb)(proc, 0, NULL, NULL); |
| put_filesystem(proc); |
| if(super == NULL){ |
| mconsole_reply(req, "Failed to get procfs superblock", 1, 0); |
| goto out; |
| } |
| up_write(&super->s_umount); |
| |
| nd.dentry = super->s_root; |
| nd.mnt = NULL; |
| nd.flags = O_RDONLY + 1; |
| nd.last_type = LAST_ROOT; |
| |
| /* START: it was experienced that the stability problems are closed |
| * if commenting out these two calls + the below read cycle. To |
| * make UML crash again, it was enough to readd either one.*/ |
| err = link_path_walk(ptr, &nd); |
| if(err){ |
| mconsole_reply(req, "Failed to look up file", 1, 0); |
| goto out_kill; |
| } |
| |
| file = dentry_open(nd.dentry, nd.mnt, O_RDONLY); |
| if(IS_ERR(file)){ |
| mconsole_reply(req, "Failed to open file", 1, 0); |
| goto out_kill; |
| } |
| /*END*/ |
| |
| buf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| if(buf == NULL){ |
| mconsole_reply(req, "Failed to allocate buffer", 1, 0); |
| goto out_fput; |
| } |
| |
| if((file->f_op != NULL) && (file->f_op->read != NULL)){ |
| do { |
| n = (*file->f_op->read)(file, buf, PAGE_SIZE - 1, |
| &file->f_pos); |
| if(n >= 0){ |
| buf[n] = '\0'; |
| mconsole_reply(req, buf, 0, (n > 0)); |
| } |
| else { |
| mconsole_reply(req, "Read of file failed", |
| 1, 0); |
| goto out_free; |
| } |
| } while(n > 0); |
| } |
| else mconsole_reply(req, "", 0, 0); |
| |
| out_free: |
| kfree(buf); |
| out_fput: |
| fput(file); |
| out_kill: |
| deactivate_super(super); |
| out: ; |
| } |
| #endif |
| |
| void mconsole_proc(struct mc_request *req) |
| { |
| char path[64]; |
| char *buf; |
| int len; |
| int fd; |
| int first_chunk = 1; |
| char *ptr = req->request.data; |
| |
| ptr += strlen("proc"); |
| while(isspace(*ptr)) ptr++; |
| snprintf(path, sizeof(path), "/proc/%s", ptr); |
| |
| fd = sys_open(path, 0, 0); |
| if (fd < 0) { |
| mconsole_reply(req, "Failed to open file", 1, 0); |
| printk("open %s: %d\n",path,fd); |
| goto out; |
| } |
| |
| buf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| if(buf == NULL){ |
| mconsole_reply(req, "Failed to allocate buffer", 1, 0); |
| goto out_close; |
| } |
| |
| for (;;) { |
| len = sys_read(fd, buf, PAGE_SIZE-1); |
| if (len < 0) { |
| mconsole_reply(req, "Read of file failed", 1, 0); |
| goto out_free; |
| } |
| /*Begin the file content on his own line.*/ |
| if (first_chunk) { |
| mconsole_reply(req, "\n", 0, 1); |
| first_chunk = 0; |
| } |
| if (len == PAGE_SIZE-1) { |
| buf[len] = '\0'; |
| mconsole_reply(req, buf, 0, 1); |
| } else { |
| buf[len] = '\0'; |
| mconsole_reply(req, buf, 0, 0); |
| break; |
| } |
| } |
| |
| out_free: |
| kfree(buf); |
| out_close: |
| sys_close(fd); |
| out: |
| /* nothing */; |
| } |
| |
| #define UML_MCONSOLE_HELPTEXT \ |
| "Commands: \n\ |
| version - Get kernel version \n\ |
| help - Print this message \n\ |
| halt - Halt UML \n\ |
| reboot - Reboot UML \n\ |
| config <dev>=<config> - Add a new device to UML; \n\ |
| same syntax as command line \n\ |
| config <dev> - Query the configuration of a device \n\ |
| remove <dev> - Remove a device from UML \n\ |
| sysrq <letter> - Performs the SysRq action controlled by the letter \n\ |
| cad - invoke the Ctl-Alt-Del handler \n\ |
| stop - pause the UML; it will do nothing until it receives a 'go' \n\ |
| go - continue the UML after a 'stop' \n\ |
| log <string> - make UML enter <string> into the kernel log\n\ |
| proc <file> - returns the contents of the UML's /proc/<file>\n\ |
| stack <pid> - returns the stack of the specified pid\n\ |
| " |
| |
| void mconsole_help(struct mc_request *req) |
| { |
| mconsole_reply(req, UML_MCONSOLE_HELPTEXT, 0, 0); |
| } |
| |
| void mconsole_halt(struct mc_request *req) |
| { |
| mconsole_reply(req, "", 0, 0); |
| machine_halt(); |
| } |
| |
| void mconsole_reboot(struct mc_request *req) |
| { |
| mconsole_reply(req, "", 0, 0); |
| machine_restart(NULL); |
| } |
| |
| extern void ctrl_alt_del(void); |
| |
| void mconsole_cad(struct mc_request *req) |
| { |
| mconsole_reply(req, "", 0, 0); |
| ctrl_alt_del(); |
| } |
| |
| void mconsole_go(struct mc_request *req) |
| { |
| mconsole_reply(req, "Not stopped", 1, 0); |
| } |
| |
| void mconsole_stop(struct mc_request *req) |
| { |
| deactivate_fd(req->originating_fd, MCONSOLE_IRQ); |
| os_set_fd_block(req->originating_fd, 1); |
| mconsole_reply(req, "", 0, 0); |
| while(mconsole_get_request(req->originating_fd, req)){ |
| if(req->cmd->handler == mconsole_go) break; |
| (*req->cmd->handler)(req); |
| } |
| os_set_fd_block(req->originating_fd, 0); |
| reactivate_fd(req->originating_fd, MCONSOLE_IRQ); |
| mconsole_reply(req, "", 0, 0); |
| } |
| |
| /* This list is populated by __initcall routines. */ |
| |
| LIST_HEAD(mconsole_devices); |
| |
| void mconsole_register_dev(struct mc_device *new) |
| { |
| list_add(&new->list, &mconsole_devices); |
| } |
| |
| static struct mc_device *mconsole_find_dev(char *name) |
| { |
| struct list_head *ele; |
| struct mc_device *dev; |
| |
| list_for_each(ele, &mconsole_devices){ |
| dev = list_entry(ele, struct mc_device, list); |
| if(!strncmp(name, dev->name, strlen(dev->name))) |
| return(dev); |
| } |
| return(NULL); |
| } |
| |
| #define CONFIG_BUF_SIZE 64 |
| |
| static void mconsole_get_config(int (*get_config)(char *, char *, int, |
| char **), |
| struct mc_request *req, char *name) |
| { |
| char default_buf[CONFIG_BUF_SIZE], *error, *buf; |
| int n, size; |
| |
| if(get_config == NULL){ |
| mconsole_reply(req, "No get_config routine defined", 1, 0); |
| return; |
| } |
| |
| error = NULL; |
| size = sizeof(default_buf)/sizeof(default_buf[0]); |
| buf = default_buf; |
| |
| while(1){ |
| n = (*get_config)(name, buf, size, &error); |
| if(error != NULL){ |
| mconsole_reply(req, error, 1, 0); |
| goto out; |
| } |
| |
| if(n <= size){ |
| mconsole_reply(req, buf, 0, 0); |
| goto out; |
| } |
| |
| if(buf != default_buf) |
| kfree(buf); |
| |
| size = n; |
| buf = kmalloc(size, GFP_KERNEL); |
| if(buf == NULL){ |
| mconsole_reply(req, "Failed to allocate buffer", 1, 0); |
| return; |
| } |
| } |
| out: |
| if(buf != default_buf) |
| kfree(buf); |
| } |
| |
| void mconsole_config(struct mc_request *req) |
| { |
| struct mc_device *dev; |
| char *ptr = req->request.data, *name; |
| int err; |
| |
| ptr += strlen("config"); |
| while(isspace(*ptr)) ptr++; |
| dev = mconsole_find_dev(ptr); |
| if(dev == NULL){ |
| mconsole_reply(req, "Bad configuration option", 1, 0); |
| return; |
| } |
| |
| name = &ptr[strlen(dev->name)]; |
| ptr = name; |
| while((*ptr != '=') && (*ptr != '\0')) |
| ptr++; |
| |
| if(*ptr == '='){ |
| err = (*dev->config)(name); |
| mconsole_reply(req, "", err, 0); |
| } |
| else mconsole_get_config(dev->get_config, req, name); |
| } |
| |
| void mconsole_remove(struct mc_request *req) |
| { |
| struct mc_device *dev; |
| char *ptr = req->request.data, *err_msg = ""; |
| char error[256]; |
| int err, start, end, n; |
| |
| ptr += strlen("remove"); |
| while(isspace(*ptr)) ptr++; |
| dev = mconsole_find_dev(ptr); |
| if(dev == NULL){ |
| mconsole_reply(req, "Bad remove option", 1, 0); |
| return; |
| } |
| |
| ptr = &ptr[strlen(dev->name)]; |
| |
| err = 1; |
| n = (*dev->id)(&ptr, &start, &end); |
| if(n < 0){ |
| err_msg = "Couldn't parse device number"; |
| goto out; |
| } |
| else if((n < start) || (n > end)){ |
| sprintf(error, "Invalid device number - must be between " |
| "%d and %d", start, end); |
| err_msg = error; |
| goto out; |
| } |
| |
| err = (*dev->remove)(n); |
| switch(err){ |
| case -ENODEV: |
| err_msg = "Device doesn't exist"; |
| break; |
| case -EBUSY: |
| err_msg = "Device is currently open"; |
| break; |
| default: |
| break; |
| } |
| out: |
| mconsole_reply(req, err_msg, err, 0); |
| } |
| |
| #ifdef CONFIG_MAGIC_SYSRQ |
| void mconsole_sysrq(struct mc_request *req) |
| { |
| char *ptr = req->request.data; |
| |
| ptr += strlen("sysrq"); |
| while(isspace(*ptr)) ptr++; |
| |
| mconsole_reply(req, "", 0, 0); |
| handle_sysrq(*ptr, ¤t->thread.regs, NULL); |
| } |
| #else |
| void mconsole_sysrq(struct mc_request *req) |
| { |
| mconsole_reply(req, "Sysrq not compiled in", 1, 0); |
| } |
| #endif |
| |
| /* Mconsole stack trace |
| * Added by Allan Graves, Jeff Dike |
| * Dumps a stacks registers to the linux console. |
| * Usage stack <pid>. |
| */ |
| void do_stack(struct mc_request *req) |
| { |
| char *ptr = req->request.data; |
| int pid_requested= -1; |
| struct task_struct *from = NULL; |
| struct task_struct *to = NULL; |
| |
| /* Would be nice: |
| * 1) Send showregs output to mconsole. |
| * 2) Add a way to stack dump all pids. |
| */ |
| |
| ptr += strlen("stack"); |
| while(isspace(*ptr)) ptr++; |
| |
| /* Should really check for multiple pids or reject bad args here */ |
| /* What do the arguments in mconsole_reply mean? */ |
| if(sscanf(ptr, "%d", &pid_requested) == 0){ |
| mconsole_reply(req, "Please specify a pid", 1, 0); |
| return; |
| } |
| |
| from = current; |
| to = find_task_by_pid(pid_requested); |
| |
| if((to == NULL) || (pid_requested == 0)) { |
| mconsole_reply(req, "Couldn't find that pid", 1, 0); |
| return; |
| } |
| to->thread.saved_task = current; |
| |
| switch_to(from, to, from); |
| mconsole_reply(req, "Stack Dumped to console and message log", 0, 0); |
| } |
| |
| void mconsole_stack(struct mc_request *req) |
| { |
| /* This command doesn't work in TT mode, so let's check and then |
| * get out of here |
| */ |
| CHOOSE_MODE(mconsole_reply(req, "Sorry, this doesn't work in TT mode", |
| 1, 0), |
| do_stack(req)); |
| } |
| |
| /* Changed by mconsole_setup, which is __setup, and called before SMP is |
| * active. |
| */ |
| static char *notify_socket = NULL; |
| |
| int mconsole_init(void) |
| { |
| /* long to avoid size mismatch warnings from gcc */ |
| long sock; |
| int err; |
| char file[256]; |
| |
| if(umid_file_name("mconsole", file, sizeof(file))) return(-1); |
| snprintf(mconsole_socket_name, sizeof(file), "%s", file); |
| |
| sock = os_create_unix_socket(file, sizeof(file), 1); |
| if (sock < 0){ |
| printk("Failed to initialize management console\n"); |
| return(1); |
| } |
| |
| register_reboot_notifier(&reboot_notifier); |
| |
| err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt, |
| SA_INTERRUPT | SA_SHIRQ | SA_SAMPLE_RANDOM, |
| "mconsole", (void *)sock); |
| if (err){ |
| printk("Failed to get IRQ for management console\n"); |
| return(1); |
| } |
| |
| if(notify_socket != NULL){ |
| notify_socket = kstrdup(notify_socket, GFP_KERNEL); |
| if(notify_socket != NULL) |
| mconsole_notify(notify_socket, MCONSOLE_SOCKET, |
| mconsole_socket_name, |
| strlen(mconsole_socket_name) + 1); |
| else printk(KERN_ERR "mconsole_setup failed to strdup " |
| "string\n"); |
| } |
| |
| printk("mconsole (version %d) initialized on %s\n", |
| MCONSOLE_VERSION, mconsole_socket_name); |
| return(0); |
| } |
| |
| __initcall(mconsole_init); |
| |
| static int write_proc_mconsole(struct file *file, const char __user *buffer, |
| unsigned long count, void *data) |
| { |
| char *buf; |
| |
| buf = kmalloc(count + 1, GFP_KERNEL); |
| if(buf == NULL) |
| return(-ENOMEM); |
| |
| if(copy_from_user(buf, buffer, count)){ |
| count = -EFAULT; |
| goto out; |
| } |
| |
| buf[count] = '\0'; |
| |
| mconsole_notify(notify_socket, MCONSOLE_USER_NOTIFY, buf, count); |
| out: |
| kfree(buf); |
| return(count); |
| } |
| |
| static int create_proc_mconsole(void) |
| { |
| struct proc_dir_entry *ent; |
| |
| if(notify_socket == NULL) return(0); |
| |
| ent = create_proc_entry("mconsole", S_IFREG | 0200, NULL); |
| if(ent == NULL){ |
| printk(KERN_INFO "create_proc_mconsole : create_proc_entry failed\n"); |
| return(0); |
| } |
| |
| ent->read_proc = NULL; |
| ent->write_proc = write_proc_mconsole; |
| return(0); |
| } |
| |
| static DEFINE_SPINLOCK(notify_spinlock); |
| |
| void lock_notify(void) |
| { |
| spin_lock(¬ify_spinlock); |
| } |
| |
| void unlock_notify(void) |
| { |
| spin_unlock(¬ify_spinlock); |
| } |
| |
| __initcall(create_proc_mconsole); |
| |
| #define NOTIFY "=notify:" |
| |
| static int mconsole_setup(char *str) |
| { |
| if(!strncmp(str, NOTIFY, strlen(NOTIFY))){ |
| str += strlen(NOTIFY); |
| notify_socket = str; |
| } |
| else printk(KERN_ERR "mconsole_setup : Unknown option - '%s'\n", str); |
| return(1); |
| } |
| |
| __setup("mconsole", mconsole_setup); |
| |
| __uml_help(mconsole_setup, |
| "mconsole=notify:<socket>\n" |
| " Requests that the mconsole driver send a message to the named Unix\n" |
| " socket containing the name of the mconsole socket. This also serves\n" |
| " to notify outside processes when UML has booted far enough to respond\n" |
| " to mconsole requests.\n\n" |
| ); |
| |
| static int notify_panic(struct notifier_block *self, unsigned long unused1, |
| void *ptr) |
| { |
| char *message = ptr; |
| |
| if(notify_socket == NULL) return(0); |
| |
| mconsole_notify(notify_socket, MCONSOLE_PANIC, message, |
| strlen(message) + 1); |
| return(0); |
| } |
| |
| static struct notifier_block panic_exit_notifier = { |
| .notifier_call = notify_panic, |
| .next = NULL, |
| .priority = 1 |
| }; |
| |
| static int add_notifier(void) |
| { |
| notifier_chain_register(&panic_notifier_list, &panic_exit_notifier); |
| return(0); |
| } |
| |
| __initcall(add_notifier); |
| |
| char *mconsole_notify_socket(void) |
| { |
| return(notify_socket); |
| } |
| |
| EXPORT_SYMBOL(mconsole_notify_socket); |
| |
| /* |
| * Overrides for Emacs so that we follow Linus's tabbing style. |
| * Emacs will notice this stuff at the end of the file and automatically |
| * adjust the settings for this buffer only. This must remain at the end |
| * of the file. |
| * --------------------------------------------------------------------------- |
| * Local variables: |
| * c-file-style: "linux" |
| * End: |
| */ |