diff options
Diffstat (limited to 'drivers/char/sysrq.c')
| -rw-r--r-- | drivers/char/sysrq.c | 250 |
1 files changed, 115 insertions, 135 deletions
diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c index d58f8231885..35082dc12ea 100644 --- a/drivers/char/sysrq.c +++ b/drivers/char/sysrq.c @@ -42,16 +42,15 @@ /* 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) + 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", @@ -59,11 +58,9 @@ static struct sysrq_key_op sysrq_loglevel_op = { .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) + struct tty_struct *tty) { if (tty) do_SAK(tty); @@ -75,12 +72,13 @@ static struct sysrq_key_op sysrq_SAK_op = { .action_msg = "SAK", .enable_mask = SYSRQ_ENABLE_KEYBOARD, }; +#else +#define sysrq_SAK_op (*(struct sysrq_key_op *)0) #endif #ifdef CONFIG_VT -/* unraw sysrq handler */ static void sysrq_handle_unraw(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { struct kbd_struct *kbd = &kbd_table[fg_console]; @@ -93,10 +91,11 @@ static struct sysrq_key_op sysrq_unraw_op = { .action_msg = "Keyboard mode set to XLATE", .enable_mask = SYSRQ_ENABLE_KEYBOARD, }; +#else +#define sysrq_unraw_op (*(struct sysrq_key_op *)0) #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) { @@ -108,16 +107,16 @@ static struct sysrq_key_op sysrq_crashdump_op = { .action_msg = "Trigger a crashdump", .enable_mask = SYSRQ_ENABLE_DUMP, }; +#else +#define sysrq_crashdump_op (*(struct sysrq_key_op *)0) #endif -/* reboot sysrq handler */ static void sysrq_handle_reboot(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { local_irq_enable(); emergency_restart(); } - static struct sysrq_key_op sysrq_reboot_op = { .handler = sysrq_handle_reboot, .help_msg = "reBoot", @@ -126,11 +125,10 @@ static struct sysrq_key_op sysrq_reboot_op = { }; static void sysrq_handle_sync(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { emergency_sync(); } - static struct sysrq_key_op sysrq_sync_op = { .handler = sysrq_handle_sync, .help_msg = "Sync", @@ -139,11 +137,10 @@ static struct sysrq_key_op sysrq_sync_op = { }; static void sysrq_handle_mountro(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { emergency_remount(); } - static struct sysrq_key_op sysrq_mountro_op = { .handler = sysrq_handle_mountro, .help_msg = "Unmount", @@ -151,28 +148,23 @@ static struct sysrq_key_op sysrq_mountro_op = { .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) +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", }; - +#else +#define sysrq_showlocks_op (*(struct sysrq_key_op *)0) #endif -/* SHOW SYSRQ HANDLERS BLOCK */ - static void sysrq_handle_showregs(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { if (pt_regs) show_regs(pt_regs); @@ -184,9 +176,8 @@ static struct sysrq_key_op sysrq_showregs_op = { .enable_mask = SYSRQ_ENABLE_DUMP, }; - static void sysrq_handle_showstate(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { show_state(); } @@ -197,9 +188,8 @@ static struct sysrq_key_op sysrq_showstate_op = { .enable_mask = SYSRQ_ENABLE_DUMP, }; - static void sysrq_handle_showmem(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { show_mem(); } @@ -210,13 +200,9 @@ static struct sysrq_key_op sysrq_showmem_op = { .enable_mask = SYSRQ_ENABLE_DUMP, }; -/* SHOW SYSRQ HANDLERS BLOCK */ - - -/* SIGNAL SYSRQ HANDLERS BLOCK */ - -/* signal sysrq helper function - * Sends a signal to all user processes */ +/* + * Signal sysrq helper function. Sends a signal to all user processes. + */ static void send_sig_all(int sig) { struct task_struct *p; @@ -229,7 +215,7 @@ static void send_sig_all(int sig) } static void sysrq_handle_term(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { send_sig_all(SIGTERM); console_loglevel = 8; @@ -243,7 +229,8 @@ static struct sysrq_key_op sysrq_term_op = { static void moom_callback(void *ignored) { - out_of_memory(&NODE_DATA(0)->node_zonelists[ZONE_NORMAL], GFP_KERNEL, 0); + out_of_memory(&NODE_DATA(0)->node_zonelists[ZONE_NORMAL], + GFP_KERNEL, 0); } static DECLARE_WORK(moom_work, moom_callback, NULL); @@ -260,7 +247,7 @@ static struct sysrq_key_op sysrq_moom_op = { }; static void sysrq_handle_kill(int key, struct pt_regs *pt_regs, - struct tty_struct *tty) + struct tty_struct *tty) { send_sig_all(SIGKILL); console_loglevel = 8; @@ -272,8 +259,6 @@ static struct sysrq_key_op sysrq_kill_op = { .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) { @@ -288,110 +273,99 @@ static struct sysrq_key_op sysrq_unrt_op = { /* 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 + +static struct sysrq_key_op *sysrq_key_table[36] = { + &sysrq_loglevel_op, /* 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 */ + + /* + * Don't use for system provided sysrqs, it is handled specially on + * sparc and will never arrive + */ + NULL, /* a */ + &sysrq_reboot_op, /* b */ + &sysrq_crashdump_op, /* c */ + &sysrq_showlocks_op, /* d */ + &sysrq_term_op, /* e */ + &sysrq_moom_op, /* f */ + NULL, /* g */ + NULL, /* h */ + &sysrq_kill_op, /* i */ + NULL, /* j */ + &sysrq_SAK_op, /* k */ + NULL, /* l */ + &sysrq_showmem_op, /* m */ + &sysrq_unrt_op, /* n */ + /* This will often be registered as 'Off' at init time */ + NULL, /* o */ + &sysrq_showregs_op, /* p */ + NULL, /* q */ + &sysrq_unraw_op, /* r */ + &sysrq_sync_op, /* s */ + &sysrq_showstate_op, /* t */ + &sysrq_mountro_op, /* u */ + /* May be assigned at init time by SMP VOYAGER */ + NULL, /* v */ + NULL, /* w */ + NULL, /* x */ + NULL, /* y */ + NULL /* z */ }; /* key2index calculation, -1 on invalid index */ -static int sysrq_key_table_key2index(int key) { +static int sysrq_key_table_key2index(int key) +{ int retval; - if ((key >= '0') && (key <= '9')) { + + if ((key >= '0') && (key <= '9')) retval = key - '0'; - } else if ((key >= 'a') && (key <= 'z')) { + else if ((key >= 'a') && (key <= 'z')) retval = key + 10 - 'a'; - } else { + 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; +struct sysrq_key_op *__sysrq_get_key_op(int key) +{ + struct sysrq_key_op *op_p = NULL; int i; - + i = sysrq_key_table_key2index(key); - op_p = (i == -1) ? NULL : sysrq_key_table[i]; + if (i != -1) + op_p = sysrq_key_table[i]; return op_p; } -static void __sysrq_put_key_op (int key, struct sysrq_key_op *op_p) { - int i; +static void __sysrq_put_key_op(int key, struct sysrq_key_op *op_p) +{ + int i = sysrq_key_table_key2index(key); - 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 + * 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) +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; + int i; unsigned long flags; spin_lock_irqsave(&sysrq_key_table_lock, flags); @@ -401,26 +375,34 @@ void __handle_sysrq(int key, struct pt_regs *pt_regs, struct tty_struct *tty, in 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? */ + /* + * 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); + printk("%s\n", op_p->action_msg); console_loglevel = orig_log_level; op_p->handler(key, pt_regs, tty); - } - else + } 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); + for (i = 0; i < ARRAY_SIZE(sysrq_key_table); i++) { + if (sysrq_key_table[i]) { + int j; + + for (j = 0; sysrq_key_table[i] != + sysrq_key_table[j]; j++) + ; + if (j != i) + continue; + printk("%s ", sysrq_key_table[i]->help_msg); + } } - printk ("\n"); + printk("\n"); console_loglevel = orig_log_level; } spin_unlock_irqrestore(&sysrq_key_table_lock, flags); @@ -430,16 +412,17 @@ void __handle_sysrq(int key, struct pt_regs *pt_regs, struct tty_struct *tty, in * 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); } +EXPORT_SYMBOL(handle_sysrq); static int __sysrq_swap_key_ops(int key, struct sysrq_key_op *insert_op_p, - struct sysrq_key_op *remove_op_p) { + struct sysrq_key_op *remove_op_p) +{ int retval; unsigned long flags; @@ -452,7 +435,6 @@ static int __sysrq_swap_key_ops(int key, struct sysrq_key_op *insert_op_p, retval = -1; } spin_unlock_irqrestore(&sysrq_key_table_lock, flags); - return retval; } @@ -460,12 +442,10 @@ int register_sysrq_key(int key, struct sysrq_key_op *op_p) { return __sysrq_swap_key_ops(key, op_p, NULL); } +EXPORT_SYMBOL(register_sysrq_key); 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); |