diff options
Diffstat (limited to 'drivers/char/sysrq.c')
| -rw-r--r-- | drivers/char/sysrq.c | 471 |
1 files changed, 0 insertions, 471 deletions
diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c deleted file mode 100644 index 5765f672e85..00000000000 --- a/drivers/char/sysrq.c +++ /dev/null @@ -1,471 +0,0 @@ -/* -*- linux-c -*- - * - * $Id: sysrq.c,v 1.15 1998/08/23 14:56:41 mj Exp $ - * - * Linux Magic System Request Key Hacks - * - * (c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz> - * based on ideas by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz> - * - * (c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com> - * overhauled to use key registration - * based upon discusions in irc://irc.openprojects.net/#kernelnewbies - */ - -#include <linux/config.h> -#include <linux/sched.h> -#include <linux/interrupt.h> -#include <linux/mm.h> -#include <linux/fs.h> -#include <linux/tty.h> -#include <linux/mount.h> -#include <linux/kdev_t.h> -#include <linux/major.h> -#include <linux/reboot.h> -#include <linux/sysrq.h> -#include <linux/kbd_kern.h> -#include <linux/quotaops.h> -#include <linux/smp_lock.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/suspend.h> -#include <linux/writeback.h> -#include <linux/buffer_head.h> /* for fsync_bdev() */ -#include <linux/swap.h> -#include <linux/spinlock.h> -#include <linux/vt_kern.h> -#include <linux/workqueue.h> -#include <linux/kexec.h> - -#include <asm/ptrace.h> - -/* Whether we react on sysrq keys or just ignore them */ -int sysrq_enabled = 1; - -/* Loglevel sysrq handler */ -static void sysrq_handle_loglevel(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - int i; - i = key - '0'; - console_loglevel = 7; - printk("Loglevel set to %d\n", i); - console_loglevel = i; -} -static struct sysrq_key_op sysrq_loglevel_op = { - .handler = sysrq_handle_loglevel, - .help_msg = "loglevel0-8", - .action_msg = "Changing Loglevel", - .enable_mask = SYSRQ_ENABLE_LOG, -}; - - -/* SAK sysrq handler */ -#ifdef CONFIG_VT -static void sysrq_handle_SAK(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - if (tty) - do_SAK(tty); - reset_vc(vc_cons[fg_console].d); -} -static struct sysrq_key_op sysrq_SAK_op = { - .handler = sysrq_handle_SAK, - .help_msg = "saK", - .action_msg = "SAK", - .enable_mask = SYSRQ_ENABLE_KEYBOARD, -}; -#endif - -#ifdef CONFIG_VT -/* unraw sysrq handler */ -static void sysrq_handle_unraw(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - struct kbd_struct *kbd = &kbd_table[fg_console]; - - if (kbd) - kbd->kbdmode = VC_XLATE; -} -static struct sysrq_key_op sysrq_unraw_op = { - .handler = sysrq_handle_unraw, - .help_msg = "unRaw", - .action_msg = "Keyboard mode set to XLATE", - .enable_mask = SYSRQ_ENABLE_KEYBOARD, -}; -#endif /* CONFIG_VT */ - -#ifdef CONFIG_KEXEC -/* crashdump sysrq handler */ -static void sysrq_handle_crashdump(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - crash_kexec(pt_regs); -} -static struct sysrq_key_op sysrq_crashdump_op = { - .handler = sysrq_handle_crashdump, - .help_msg = "Crashdump", - .action_msg = "Trigger a crashdump", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; -#endif - -/* reboot sysrq handler */ -static void sysrq_handle_reboot(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - local_irq_enable(); - emergency_restart(); -} - -static struct sysrq_key_op sysrq_reboot_op = { - .handler = sysrq_handle_reboot, - .help_msg = "reBoot", - .action_msg = "Resetting", - .enable_mask = SYSRQ_ENABLE_BOOT, -}; - -static void sysrq_handle_sync(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - emergency_sync(); -} - -static struct sysrq_key_op sysrq_sync_op = { - .handler = sysrq_handle_sync, - .help_msg = "Sync", - .action_msg = "Emergency Sync", - .enable_mask = SYSRQ_ENABLE_SYNC, -}; - -static void sysrq_handle_mountro(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - emergency_remount(); -} - -static struct sysrq_key_op sysrq_mountro_op = { - .handler = sysrq_handle_mountro, - .help_msg = "Unmount", - .action_msg = "Emergency Remount R/O", - .enable_mask = SYSRQ_ENABLE_REMOUNT, -}; - -/* END SYNC SYSRQ HANDLERS BLOCK */ - -#ifdef CONFIG_DEBUG_MUTEXES - -static void -sysrq_handle_showlocks(int key, struct pt_regs *pt_regs, struct tty_struct *tty) -{ - mutex_debug_show_all_locks(); -} - -static struct sysrq_key_op sysrq_showlocks_op = { - .handler = sysrq_handle_showlocks, - .help_msg = "show-all-locks(D)", - .action_msg = "Show Locks Held", -}; - -#endif - -/* SHOW SYSRQ HANDLERS BLOCK */ - -static void sysrq_handle_showregs(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - if (pt_regs) - show_regs(pt_regs); -} -static struct sysrq_key_op sysrq_showregs_op = { - .handler = sysrq_handle_showregs, - .help_msg = "showPc", - .action_msg = "Show Regs", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; - - -static void sysrq_handle_showstate(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - show_state(); -} -static struct sysrq_key_op sysrq_showstate_op = { - .handler = sysrq_handle_showstate, - .help_msg = "showTasks", - .action_msg = "Show State", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; - - -static void sysrq_handle_showmem(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - show_mem(); -} -static struct sysrq_key_op sysrq_showmem_op = { - .handler = sysrq_handle_showmem, - .help_msg = "showMem", - .action_msg = "Show Memory", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; - -/* SHOW SYSRQ HANDLERS BLOCK */ - - -/* SIGNAL SYSRQ HANDLERS BLOCK */ - -/* signal sysrq helper function - * Sends a signal to all user processes */ -static void send_sig_all(int sig) -{ - struct task_struct *p; - - for_each_process(p) { - if (p->mm && p->pid != 1) - /* Not swapper, init nor kernel thread */ - force_sig(sig, p); - } -} - -static void sysrq_handle_term(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - send_sig_all(SIGTERM); - console_loglevel = 8; -} -static struct sysrq_key_op sysrq_term_op = { - .handler = sysrq_handle_term, - .help_msg = "tErm", - .action_msg = "Terminate All Tasks", - .enable_mask = SYSRQ_ENABLE_SIGNAL, -}; - -static void moom_callback(void *ignored) -{ - out_of_memory(GFP_KERNEL, 0); -} - -static DECLARE_WORK(moom_work, moom_callback, NULL); - -static void sysrq_handle_moom(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - schedule_work(&moom_work); -} -static struct sysrq_key_op sysrq_moom_op = { - .handler = sysrq_handle_moom, - .help_msg = "Full", - .action_msg = "Manual OOM execution", -}; - -static void sysrq_handle_kill(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - send_sig_all(SIGKILL); - console_loglevel = 8; -} -static struct sysrq_key_op sysrq_kill_op = { - .handler = sysrq_handle_kill, - .help_msg = "kIll", - .action_msg = "Kill All Tasks", - .enable_mask = SYSRQ_ENABLE_SIGNAL, -}; - -/* END SIGNAL SYSRQ HANDLERS BLOCK */ - -static void sysrq_handle_unrt(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) -{ - normalize_rt_tasks(); -} -static struct sysrq_key_op sysrq_unrt_op = { - .handler = sysrq_handle_unrt, - .help_msg = "Nice", - .action_msg = "Nice All RT Tasks", - .enable_mask = SYSRQ_ENABLE_RTNICE, -}; - -/* Key Operations table and lock */ -static DEFINE_SPINLOCK(sysrq_key_table_lock); -#define SYSRQ_KEY_TABLE_LENGTH 36 -static struct sysrq_key_op *sysrq_key_table[SYSRQ_KEY_TABLE_LENGTH] = { -/* 0 */ &sysrq_loglevel_op, -/* 1 */ &sysrq_loglevel_op, -/* 2 */ &sysrq_loglevel_op, -/* 3 */ &sysrq_loglevel_op, -/* 4 */ &sysrq_loglevel_op, -/* 5 */ &sysrq_loglevel_op, -/* 6 */ &sysrq_loglevel_op, -/* 7 */ &sysrq_loglevel_op, -/* 8 */ &sysrq_loglevel_op, -/* 9 */ &sysrq_loglevel_op, -/* a */ NULL, /* Don't use for system provided sysrqs, - it is handled specially on the sparc - and will never arrive */ -/* b */ &sysrq_reboot_op, -#ifdef CONFIG_KEXEC -/* c */ &sysrq_crashdump_op, -#else -/* c */ NULL, -#endif -#ifdef CONFIG_DEBUG_MUTEXES -/* d */ &sysrq_showlocks_op, -#else -/* d */ NULL, -#endif -/* e */ &sysrq_term_op, -/* f */ &sysrq_moom_op, -/* g */ NULL, -/* h */ NULL, -/* i */ &sysrq_kill_op, -/* j */ NULL, -#ifdef CONFIG_VT -/* k */ &sysrq_SAK_op, -#else -/* k */ NULL, -#endif -/* l */ NULL, -/* m */ &sysrq_showmem_op, -/* n */ &sysrq_unrt_op, -/* o */ NULL, /* This will often be registered - as 'Off' at init time */ -/* p */ &sysrq_showregs_op, -/* q */ NULL, -#ifdef CONFIG_VT -/* r */ &sysrq_unraw_op, -#else -/* r */ NULL, -#endif -/* s */ &sysrq_sync_op, -/* t */ &sysrq_showstate_op, -/* u */ &sysrq_mountro_op, -/* v */ NULL, /* May be assigned at init time by SMP VOYAGER */ -/* w */ NULL, -/* x */ NULL, -/* y */ NULL, -/* z */ NULL -}; - -/* key2index calculation, -1 on invalid index */ -static int sysrq_key_table_key2index(int key) { - int retval; - if ((key >= '0') && (key <= '9')) { - retval = key - '0'; - } else if ((key >= 'a') && (key <= 'z')) { - retval = key + 10 - 'a'; - } else { - retval = -1; - } - return retval; -} - -/* - * get and put functions for the table, exposed to modules. - */ - -struct sysrq_key_op *__sysrq_get_key_op (int key) { - struct sysrq_key_op *op_p; - int i; - - i = sysrq_key_table_key2index(key); - op_p = (i == -1) ? NULL : sysrq_key_table[i]; - return op_p; -} - -static void __sysrq_put_key_op (int key, struct sysrq_key_op *op_p) { - int i; - - i = sysrq_key_table_key2index(key); - if (i != -1) - sysrq_key_table[i] = op_p; -} - -/* - * This is the non-locking version of handle_sysrq - * It must/can only be called by sysrq key handlers, - * as they are inside of the lock - */ - -void __handle_sysrq(int key, struct pt_regs *pt_regs, struct tty_struct *tty, int check_mask) -{ - struct sysrq_key_op *op_p; - int orig_log_level; - int i, j; - unsigned long flags; - - spin_lock_irqsave(&sysrq_key_table_lock, flags); - orig_log_level = console_loglevel; - console_loglevel = 7; - printk(KERN_INFO "SysRq : "); - - op_p = __sysrq_get_key_op(key); - if (op_p) { - /* Should we check for enabled operations (/proc/sysrq-trigger should not) - * and is the invoked operation enabled? */ - if (!check_mask || sysrq_enabled == 1 || - (sysrq_enabled & op_p->enable_mask)) { - printk ("%s\n", op_p->action_msg); - console_loglevel = orig_log_level; - op_p->handler(key, pt_regs, tty); - } - else - printk("This sysrq operation is disabled.\n"); - } else { - printk("HELP : "); - /* Only print the help msg once per handler */ - for (i=0; i<SYSRQ_KEY_TABLE_LENGTH; i++) - if (sysrq_key_table[i]) { - for (j=0; sysrq_key_table[i] != sysrq_key_table[j]; j++); - if (j == i) - printk ("%s ", sysrq_key_table[i]->help_msg); - } - printk ("\n"); - console_loglevel = orig_log_level; - } - spin_unlock_irqrestore(&sysrq_key_table_lock, flags); -} - -/* - * This function is called by the keyboard handler when SysRq is pressed - * and any other keycode arrives. - */ - -void handle_sysrq(int key, struct pt_regs *pt_regs, struct tty_struct *tty) -{ - if (!sysrq_enabled) - return; - __handle_sysrq(key, pt_regs, tty, 1); -} - -static int __sysrq_swap_key_ops(int key, struct sysrq_key_op *insert_op_p, - struct sysrq_key_op *remove_op_p) { - - int retval; - unsigned long flags; - - spin_lock_irqsave(&sysrq_key_table_lock, flags); - if (__sysrq_get_key_op(key) == remove_op_p) { - __sysrq_put_key_op(key, insert_op_p); - retval = 0; - } else { - retval = -1; - } - spin_unlock_irqrestore(&sysrq_key_table_lock, flags); - - return retval; -} - -int register_sysrq_key(int key, struct sysrq_key_op *op_p) -{ - return __sysrq_swap_key_ops(key, op_p, NULL); -} - -int unregister_sysrq_key(int key, struct sysrq_key_op *op_p) -{ - return __sysrq_swap_key_ops(key, NULL, op_p); -} - -EXPORT_SYMBOL(handle_sysrq); -EXPORT_SYMBOL(register_sysrq_key); -EXPORT_SYMBOL(unregister_sysrq_key); |