Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

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

[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

drivers/char/sysrq.c

+115 −135
Original line number Diff line number Diff line
@@ -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);
@@ -401,25 +375,33 @@ 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);

			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)

				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");

		console_loglevel = orig_log_level;

	}
@@ -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);