* 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/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 <linux/irq.h>
+#include <linux/vserver/debug.h>
#include <asm/ptrace.h>
-
-extern void reset_vc(unsigned int);
+#include <asm/irq_regs.h>
/* Whether we react on sysrq keys or just ignore them */
-int sysrq_enabled = 1;
+int __read_mostly __sysrq_enabled = 1;
-/* Machine specific power off function */
-void (*sysrq_power_off)(void);
+static int __read_mostly sysrq_always_enabled;
+
+int sysrq_on(void)
+{
+ return __sysrq_enabled || sysrq_always_enabled;
+}
-/* Loglevel sysrq handler */
-static void sysrq_handle_loglevel(int key, struct pt_regs *pt_regs,
- struct tty_struct *tty)
+/*
+ * A value of 1 means 'all', other nonzero values are an op mask:
+ */
+static inline int sysrq_on_mask(int mask)
+{
+ return sysrq_always_enabled || __sysrq_enabled == 1 ||
+ (__sysrq_enabled & mask);
+}
+
+static int __init sysrq_always_enabled_setup(char *str)
+{
+ sysrq_always_enabled = 1;
+ printk(KERN_INFO "debug: sysrq always enabled.\n");
+
+ return 1;
+}
+
+__setup("sysrq_always_enabled", sysrq_always_enabled_setup);
+
+
+static void sysrq_handle_loglevel(int key, 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)
+static void sysrq_handle_SAK(int key, struct tty_struct *tty)
{
if (tty)
do_SAK(tty);
- reset_vc(fg_console);
+ 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,
};
+#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)
+static void sysrq_handle_unraw(int key, struct tty_struct *tty)
{
struct kbd_struct *kbd = &kbd_table[fg_console];
.handler = sysrq_handle_unraw,
.help_msg = "unRaw",
.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 */
-/* reboot sysrq handler */
-static void sysrq_handle_reboot(int key, struct pt_regs *pt_regs,
- struct tty_struct *tty)
+static void sysrq_handle_crashdump(int key, struct tty_struct *tty)
{
- machine_restart(NULL);
+#ifdef CONFIG_KEXEC
+ crash_kexec(get_irq_regs());
+ /* can't get here if crash image is loaded */
+ printk("Kexec: Warning: crash image not loaded\n");
+#endif
+ if (panic_on_oops)
+ panic("SysRq-triggered panic!\n");
}
+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,
+};
+static void sysrq_handle_reboot(int key, struct tty_struct *tty)
+{
+ lockdep_off();
+ 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)
+static void sysrq_handle_sync(int key, 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)
+static void sysrq_handle_mountro(int key, 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_LOCKDEP
+static void sysrq_handle_showlocks(int key, struct tty_struct *tty)
+{
+ debug_show_all_locks();
+}
-/* SHOW SYSRQ HANDLERS BLOCK */
+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
-static void sysrq_handle_showregs(int key, struct pt_regs *pt_regs,
- struct tty_struct *tty)
+static void sysrq_handle_showregs(int key, struct tty_struct *tty)
{
- if (pt_regs)
- show_regs(pt_regs);
+ struct pt_regs *regs = get_irq_regs();
+ if (regs)
+ show_regs(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)
+static void sysrq_handle_showstate(int key, struct tty_struct *tty)
{
show_state();
}
.handler = sysrq_handle_showstate,
.help_msg = "showTasks",
.action_msg = "Show State",
+ .enable_mask = SYSRQ_ENABLE_DUMP,
+};
+
+static void sysrq_handle_showstate_blocked(int key, struct tty_struct *tty)
+{
+ show_state_filter(TASK_UNINTERRUPTIBLE);
+}
+static struct sysrq_key_op sysrq_showstate_blocked_op = {
+ .handler = sysrq_handle_showstate_blocked,
+ .help_msg = "shoW-blocked-tasks",
+ .action_msg = "Show Blocked State",
+ .enable_mask = SYSRQ_ENABLE_DUMP,
};
-static void sysrq_handle_showmem(int key, struct pt_regs *pt_regs,
- struct tty_struct *tty)
+static void sysrq_handle_showmem(int key, struct tty_struct *tty)
{
show_mem();
}
.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 */
+/*
+ * 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)
+ if (p->mm && !is_init(p))
/* 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)
+static void sysrq_handle_term(int key, struct tty_struct *tty)
{
send_sig_all(SIGTERM);
console_loglevel = 8;
.handler = sysrq_handle_term,
.help_msg = "tErm",
.action_msg = "Terminate All Tasks",
+ .enable_mask = SYSRQ_ENABLE_SIGNAL,
+};
+
+static void moom_callback(struct work_struct *ignored)
+{
+ out_of_memory(&NODE_DATA(0)->node_zonelists[ZONE_NORMAL],
+ GFP_KERNEL, 0);
+}
+
+static DECLARE_WORK(moom_work, moom_callback);
+
+static void sysrq_handle_moom(int key, 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)
+static void sysrq_handle_kill(int key, struct tty_struct *tty)
{
send_sig_all(SIGKILL);
console_loglevel = 8;
.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 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 spinlock_t sysrq_key_table_lock = SPIN_LOCK_UNLOCKED;
-#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,
-/* c */ NULL,
-/* d */ NULL,
-/* e */ &sysrq_term_op,
-/* f */ NULL,
-/* g */ NULL,
-/* h */ NULL,
-/* i */ &sysrq_kill_op,
-/* j */ NULL,
-#ifdef CONFIG_VT
-/* k */ &sysrq_SAK_op,
-#else
-/* k */ NULL,
+#ifdef CONFIG_VSERVER_DEBUG
+static void sysrq_handle_vxinfo(int key, struct tty_struct *tty)
+{
+ dump_vx_info_inactive((key == 'x')?0:1);
+}
+
+static struct sysrq_key_op sysrq_showvxinfo_op = {
+ .handler = sysrq_handle_vxinfo,
+ .help_msg = "conteXt",
+ .action_msg = "Show Context Info",
+ .enable_mask = SYSRQ_ENABLE_DUMP,
+};
#endif
-/* l */ NULL,
-/* m */ &sysrq_showmem_op,
-/* n */ NULL,
-/* 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,
+
+/* Key Operations table and lock */
+static DEFINE_SPINLOCK(sysrq_key_table_lock);
+
+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 */
+
+ /*
+ * a: 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 & ibm_emac driver debug */
+ &sysrq_showlocks_op, /* d */
+ &sysrq_term_op, /* e */
+ &sysrq_moom_op, /* f */
+ /* g: May be registered by ppc for kgdb */
+ NULL, /* g */
+ NULL, /* h */
+ &sysrq_kill_op, /* i */
+ NULL, /* j */
+ &sysrq_SAK_op, /* k */
+ NULL, /* l */
+ &sysrq_showmem_op, /* m */
+ &sysrq_unrt_op, /* n */
+ /* o: 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 */
+ /* v: May be registered at init time by SMP VOYAGER */
+ NULL, /* v */
+ &sysrq_showstate_blocked_op, /* w */
+ /* x: May be registered on ppc/powerpc for xmon */
+ NULL, /* x */
+ NULL, /* y */
+#ifdef CONFIG_VSERVER_DEBUG
+ &sysrq_showvxinfo_op, /* z */
#else
-/* r */ NULL,
+ NULL, /* z */
#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) {
+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 if ((key >= 'A') && (key <= 'Z'))
+ retval = key + 10 - 'A';
+ else
retval = -1;
- }
return retval;
}
-/*
- * table lock and unlocking functions, exposed to modules
- */
-
-void __sysrq_lock_table (void) { spin_lock(&sysrq_key_table_lock); }
-
-void __sysrq_unlock_table (void) { spin_unlock(&sysrq_key_table_lock); }
-
/*
* 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;
}
-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 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;
-
- __sysrq_lock_table();
- __handle_sysrq_nolock(key, pt_regs, tty);
- __sysrq_unlock_table();
-}
-
-/*
- * 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_nolock(int key, struct pt_regs *pt_regs,
- struct tty_struct *tty)
+void __handle_sysrq(int key, struct tty_struct *tty, int check_mask)
{
struct sysrq_key_op *op_p;
int orig_log_level;
- int i, j;
-
- if (!sysrq_enabled)
- return;
+ int i;
+ 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) {
- printk ("%s\n", op_p->action_msg);
- console_loglevel = orig_log_level;
- op_p->handler(key, pt_regs, tty);
+ /*
+ * Should we check for enabled operations (/proc/sysrq-trigger
+ * should not) and is the invoked operation enabled?
+ */
+ if (!check_mask || sysrq_on_mask(op_p->enable_mask)) {
+ printk("%s\n", op_p->action_msg);
+ console_loglevel = orig_log_level;
+ op_p->handler(key, 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);
+ 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);
}
+/*
+ * This function is called by the keyboard handler when SysRq is pressed
+ * and any other keycode arrives.
+ */
+void handle_sysrq(int key, struct tty_struct *tty)
+{
+ if (sysrq_on())
+ __handle_sysrq(key, tty, 1);
+}
EXPORT_SYMBOL(handle_sysrq);
-EXPORT_SYMBOL(__handle_sysrq_nolock);
-EXPORT_SYMBOL(__sysrq_lock_table);
-EXPORT_SYMBOL(__sysrq_unlock_table);
-EXPORT_SYMBOL(__sysrq_get_key_op);
-EXPORT_SYMBOL(__sysrq_put_key_op);
+
+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);
+}
+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(unregister_sysrq_key);
git://git.onelab.eu / linux-2.6.git / blobdiff