Commit bf36b901 authored by Andrew Morton's avatar Andrew Morton Committed by Linus Torvalds

[PATCH] sysrq cleanup

sysrq.c is fairly revolting.  Fix.
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 21e4f952
......@@ -42,7 +42,6 @@
/* 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)
{
......@@ -59,8 +58,6 @@ 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)
......@@ -75,10 +72,11 @@ 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)
{
......@@ -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)
{
local_irq_enable();
emergency_restart();
}
static struct sysrq_key_op sysrq_reboot_op = {
.handler = sysrq_handle_reboot,
.help_msg = "reBoot",
......@@ -130,7 +129,6 @@ static void sysrq_handle_sync(int key, struct pt_regs *pt_regs,
{
emergency_sync();
}
static struct sysrq_key_op sysrq_sync_op = {
.handler = sysrq_handle_sync,
.help_msg = "Sync",
......@@ -143,7 +141,6 @@ static void sysrq_handle_mountro(int key, struct pt_regs *pt_regs,
{
emergency_remount();
}
static struct sysrq_key_op sysrq_mountro_op = {
.handler = sysrq_handle_mountro,
.help_msg = "Unmount",
......@@ -151,26 +148,21 @@ 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)
{
......@@ -184,7 +176,6 @@ 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)
{
......@@ -197,7 +188,6 @@ 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)
{
......@@ -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;
......@@ -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);
......@@ -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++)
for (i = 0; i < ARRAY_SIZE(sysrq_key_table); 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);
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);
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