+++ /dev/null
-/*
- * 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
- *
- * Copyright (c) 2010 Dmitry Torokhov
- * Input handler conversion
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/sched.h>
-#include <linux/interrupt.h>
-#include <linux/mm.h>
-#include <linux/fs.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/proc_fs.h>
-#include <linux/nmi.h>
-#include <linux/quotaops.h>
-#include <linux/perf_event.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/hrtimer.h>
-#include <linux/oom.h>
-#include <linux/slab.h>
-#include <linux/input.h>
-
-#include <asm/ptrace.h>
-#include <asm/irq_regs.h>
-
-/* Whether we react on sysrq keys or just ignore them */
-static int __read_mostly sysrq_enabled = 1;
-static bool __read_mostly sysrq_always_enabled;
-
-static bool sysrq_on(void)
-{
- return sysrq_enabled || sysrq_always_enabled;
-}
-
-/*
- * A value of 1 means 'all', other nonzero values are an op mask:
- */
-static bool 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 = true;
- pr_info("sysrq always enabled.\n");
-
- return 1;
-}
-
-__setup("sysrq_always_enabled", sysrq_always_enabled_setup);
-
-
-static void sysrq_handle_loglevel(int key)
-{
- 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 = "loglevel(0-9)",
- .action_msg = "Changing Loglevel",
- .enable_mask = SYSRQ_ENABLE_LOG,
-};
-
-#ifdef CONFIG_VT
-static void sysrq_handle_SAK(int key)
-{
- struct work_struct *SAK_work = &vc_cons[fg_console].SAK_work;
- schedule_work(SAK_work);
-}
-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 *)NULL)
-#endif
-
-#ifdef CONFIG_VT
-static void sysrq_handle_unraw(int key)
-{
- struct kbd_struct *kbd = &kbd_table[fg_console];
-
- if (kbd)
- kbd->kbdmode = default_utf8 ? VC_UNICODE : VC_XLATE;
-}
-static struct sysrq_key_op sysrq_unraw_op = {
- .handler = sysrq_handle_unraw,
- .help_msg = "unRaw",
- .action_msg = "Keyboard mode set to system default",
- .enable_mask = SYSRQ_ENABLE_KEYBOARD,
-};
-#else
-#define sysrq_unraw_op (*(struct sysrq_key_op *)NULL)
-#endif /* CONFIG_VT */
-
-static void sysrq_handle_crash(int key)
-{
- char *killer = NULL;
-
- panic_on_oops = 1; /* force panic */
- wmb();
- *killer = 1;
-}
-static struct sysrq_key_op sysrq_crash_op = {
- .handler = sysrq_handle_crash,
- .help_msg = "Crash",
- .action_msg = "Trigger a crash",
- .enable_mask = SYSRQ_ENABLE_DUMP,
-};
-
-static void sysrq_handle_reboot(int key)
-{
- 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)
-{
- 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_show_timers(int key)
-{
- sysrq_timer_list_show();
-}
-
-static struct sysrq_key_op sysrq_show_timers_op = {
- .handler = sysrq_handle_show_timers,
- .help_msg = "show-all-timers(Q)",
- .action_msg = "Show clockevent devices & pending hrtimers (no others)",
-};
-
-static void sysrq_handle_mountro(int key)
-{
- 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,
-};
-
-#ifdef CONFIG_LOCKDEP
-static void sysrq_handle_showlocks(int key)
-{
- 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 *)NULL)
-#endif
-
-#ifdef CONFIG_SMP
-static DEFINE_SPINLOCK(show_lock);
-
-static void showacpu(void *dummy)
-{
- unsigned long flags;
-
- /* Idle CPUs have no interesting backtrace. */
- if (idle_cpu(smp_processor_id()))
- return;
-
- spin_lock_irqsave(&show_lock, flags);
- printk(KERN_INFO "CPU%d:\n", smp_processor_id());
- show_stack(NULL, NULL);
- spin_unlock_irqrestore(&show_lock, flags);
-}
-
-static void sysrq_showregs_othercpus(struct work_struct *dummy)
-{
- smp_call_function(showacpu, NULL, 0);
-}
-
-static DECLARE_WORK(sysrq_showallcpus, sysrq_showregs_othercpus);
-
-static void sysrq_handle_showallcpus(int key)
-{
- /*
- * Fall back to the workqueue based printing if the
- * backtrace printing did not succeed or the
- * architecture has no support for it:
- */
- if (!trigger_all_cpu_backtrace()) {
- struct pt_regs *regs = get_irq_regs();
-
- if (regs) {
- printk(KERN_INFO "CPU%d:\n", smp_processor_id());
- show_regs(regs);
- }
- schedule_work(&sysrq_showallcpus);
- }
-}
-
-static struct sysrq_key_op sysrq_showallcpus_op = {
- .handler = sysrq_handle_showallcpus,
- .help_msg = "show-backtrace-all-active-cpus(L)",
- .action_msg = "Show backtrace of all active CPUs",
- .enable_mask = SYSRQ_ENABLE_DUMP,
-};
-#endif
-
-static void sysrq_handle_showregs(int key)
-{
- struct pt_regs *regs = get_irq_regs();
- if (regs)
- show_regs(regs);
- perf_event_print_debug();
-}
-static struct sysrq_key_op sysrq_showregs_op = {
- .handler = sysrq_handle_showregs,
- .help_msg = "show-registers(P)",
- .action_msg = "Show Regs",
- .enable_mask = SYSRQ_ENABLE_DUMP,
-};
-
-static void sysrq_handle_showstate(int key)
-{
- show_state();
-}
-static struct sysrq_key_op sysrq_showstate_op = {
- .handler = sysrq_handle_showstate,
- .help_msg = "show-task-states(T)",
- .action_msg = "Show State",
- .enable_mask = SYSRQ_ENABLE_DUMP,
-};
-
-static void sysrq_handle_showstate_blocked(int key)
-{
- show_state_filter(TASK_UNINTERRUPTIBLE);
-}
-static struct sysrq_key_op sysrq_showstate_blocked_op = {
- .handler = sysrq_handle_showstate_blocked,
- .help_msg = "show-blocked-tasks(W)",
- .action_msg = "Show Blocked State",
- .enable_mask = SYSRQ_ENABLE_DUMP,
-};
-
-#ifdef CONFIG_TRACING
-#include <linux/ftrace.h>
-
-static void sysrq_ftrace_dump(int key)
-{
- ftrace_dump(DUMP_ALL);
-}
-static struct sysrq_key_op sysrq_ftrace_dump_op = {
- .handler = sysrq_ftrace_dump,
- .help_msg = "dump-ftrace-buffer(Z)",
- .action_msg = "Dump ftrace buffer",
- .enable_mask = SYSRQ_ENABLE_DUMP,
-};
-#else
-#define sysrq_ftrace_dump_op (*(struct sysrq_key_op *)NULL)
-#endif
-
-static void sysrq_handle_showmem(int key)
-{
- show_mem();
-}
-static struct sysrq_key_op sysrq_showmem_op = {
- .handler = sysrq_handle_showmem,
- .help_msg = "show-memory-usage(M)",
- .action_msg = "Show Memory",
- .enable_mask = SYSRQ_ENABLE_DUMP,
-};
-
-/*
- * 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 && !is_global_init(p))
- /* Not swapper, init nor kernel thread */
- force_sig(sig, p);
- }
-}
-
-static void sysrq_handle_term(int key)
-{
- send_sig_all(SIGTERM);
- console_loglevel = 8;
-}
-static struct sysrq_key_op sysrq_term_op = {
- .handler = sysrq_handle_term,
- .help_msg = "terminate-all-tasks(E)",
- .action_msg = "Terminate All Tasks",
- .enable_mask = SYSRQ_ENABLE_SIGNAL,
-};
-
-static void moom_callback(struct work_struct *ignored)
-{
- out_of_memory(node_zonelist(0, GFP_KERNEL), GFP_KERNEL, 0, NULL);
-}
-
-static DECLARE_WORK(moom_work, moom_callback);
-
-static void sysrq_handle_moom(int key)
-{
- schedule_work(&moom_work);
-}
-static struct sysrq_key_op sysrq_moom_op = {
- .handler = sysrq_handle_moom,
- .help_msg = "memory-full-oom-kill(F)",
- .action_msg = "Manual OOM execution",
- .enable_mask = SYSRQ_ENABLE_SIGNAL,
-};
-
-#ifdef CONFIG_BLOCK
-static void sysrq_handle_thaw(int key)
-{
- emergency_thaw_all();
-}
-static struct sysrq_key_op sysrq_thaw_op = {
- .handler = sysrq_handle_thaw,
- .help_msg = "thaw-filesystems(J)",
- .action_msg = "Emergency Thaw of all frozen filesystems",
- .enable_mask = SYSRQ_ENABLE_SIGNAL,
-};
-#endif
-
-static void sysrq_handle_kill(int key)
-{
- send_sig_all(SIGKILL);
- console_loglevel = 8;
-}
-static struct sysrq_key_op sysrq_kill_op = {
- .handler = sysrq_handle_kill,
- .help_msg = "kill-all-tasks(I)",
- .action_msg = "Kill All Tasks",
- .enable_mask = SYSRQ_ENABLE_SIGNAL,
-};
-
-static void sysrq_handle_unrt(int key)
-{
- normalize_rt_tasks();
-}
-static struct sysrq_key_op sysrq_unrt_op = {
- .handler = sysrq_handle_unrt,
- .help_msg = "nice-all-RT-tasks(N)",
- .action_msg = "Nice All RT Tasks",
- .enable_mask = SYSRQ_ENABLE_RTNICE,
-};
-
-/* 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_crash_op, /* c & ibm_emac driver debug */
- &sysrq_showlocks_op, /* d */
- &sysrq_term_op, /* e */
- &sysrq_moom_op, /* f */
- /* g: May be registered for the kernel debugger */
- NULL, /* g */
- NULL, /* h - reserved for help */
- &sysrq_kill_op, /* i */
-#ifdef CONFIG_BLOCK
- &sysrq_thaw_op, /* j */
-#else
- NULL, /* j */
-#endif
- &sysrq_SAK_op, /* k */
-#ifdef CONFIG_SMP
- &sysrq_showallcpus_op, /* l */
-#else
- NULL, /* l */
-#endif
- &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 */
- &sysrq_show_timers_op, /* q */
- &sysrq_unraw_op, /* r */
- &sysrq_sync_op, /* s */
- &sysrq_showstate_op, /* t */
- &sysrq_mountro_op, /* u */
- /* v: May be registered for frame buffer console restore */
- NULL, /* v */
- &sysrq_showstate_blocked_op, /* w */
- /* x: May be registered on ppc/powerpc for xmon */
- NULL, /* x */
- /* y: May be registered on sparc64 for global register dump */
- NULL, /* y */
- &sysrq_ftrace_dump_op, /* z */
-};
-
-/* 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 = NULL;
- int i;
-
- i = sysrq_key_table_key2index(key);
- 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 = sysrq_key_table_key2index(key);
-
- if (i != -1)
- sysrq_key_table[i] = op_p;
-}
-
-void __handle_sysrq(int key, bool check_mask)
-{
- struct sysrq_key_op *op_p;
- int orig_log_level;
- int i;
- unsigned long flags;
-
- spin_lock_irqsave(&sysrq_key_table_lock, flags);
- /*
- * Raise the apparent loglevel to maximum so that the sysrq header
- * is shown to provide the user with positive feedback. We do not
- * simply emit this at KERN_EMERG as that would change message
- * routing in the consumers of /proc/kmsg.
- */
- 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_on_mask(op_p->enable_mask)) {
- printk("%s\n", op_p->action_msg);
- console_loglevel = orig_log_level;
- op_p->handler(key);
- } else {
- printk("This sysrq operation is disabled.\n");
- }
- } else {
- printk("HELP : ");
- /* Only print the help msg once per handler */
- 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");
- console_loglevel = orig_log_level;
- }
- spin_unlock_irqrestore(&sysrq_key_table_lock, flags);
-}
-
-void handle_sysrq(int key)
-{
- if (sysrq_on())
- __handle_sysrq(key, true);
-}
-EXPORT_SYMBOL(handle_sysrq);
-
-#ifdef CONFIG_INPUT
-
-/* Simple translation table for the SysRq keys */
-static const unsigned char sysrq_xlate[KEY_MAX + 1] =
- "\000\0331234567890-=\177\t" /* 0x00 - 0x0f */
- "qwertyuiop[]\r\000as" /* 0x10 - 0x1f */
- "dfghjkl;'`\000\\zxcv" /* 0x20 - 0x2f */
- "bnm,./\000*\000 \000\201\202\203\204\205" /* 0x30 - 0x3f */
- "\206\207\210\211\212\000\000789-456+1" /* 0x40 - 0x4f */
- "230\177\000\000\213\214\000\000\000\000\000\000\000\000\000\000" /* 0x50 - 0x5f */
- "\r\000/"; /* 0x60 - 0x6f */
-
-static bool sysrq_down;
-static int sysrq_alt_use;
-static int sysrq_alt;
-static DEFINE_SPINLOCK(sysrq_event_lock);
-
-static bool sysrq_filter(struct input_handle *handle, unsigned int type,
- unsigned int code, int value)
-{
- bool suppress;
-
- /* We are called with interrupts disabled, just take the lock */
- spin_lock(&sysrq_event_lock);
-
- if (type != EV_KEY)
- goto out;
-
- switch (code) {
-
- case KEY_LEFTALT:
- case KEY_RIGHTALT:
- if (value)
- sysrq_alt = code;
- else {
- if (sysrq_down && code == sysrq_alt_use)
- sysrq_down = false;
-
- sysrq_alt = 0;
- }
- break;
-
- case KEY_SYSRQ:
- if (value == 1 && sysrq_alt) {
- sysrq_down = true;
- sysrq_alt_use = sysrq_alt;
- }
- break;
-
- default:
- if (sysrq_down && value && value != 2)
- __handle_sysrq(sysrq_xlate[code], true);
- break;
- }
-
-out:
- suppress = sysrq_down;
- spin_unlock(&sysrq_event_lock);
-
- return suppress;
-}
-
-static int sysrq_connect(struct input_handler *handler,
- struct input_dev *dev,
- const struct input_device_id *id)
-{
- struct input_handle *handle;
- int error;
-
- sysrq_down = false;
- sysrq_alt = 0;
-
- handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
- if (!handle)
- return -ENOMEM;
-
- handle->dev = dev;
- handle->handler = handler;
- handle->name = "sysrq";
-
- error = input_register_handle(handle);
- if (error) {
- pr_err("Failed to register input sysrq handler, error %d\n",
- error);
- goto err_free;
- }
-
- error = input_open_device(handle);
- if (error) {
- pr_err("Failed to open input device, error %d\n", error);
- goto err_unregister;
- }
-
- return 0;
-
- err_unregister:
- input_unregister_handle(handle);
- err_free:
- kfree(handle);
- return error;
-}
-
-static void sysrq_disconnect(struct input_handle *handle)
-{
- input_close_device(handle);
- input_unregister_handle(handle);
- kfree(handle);
-}
-
-/*
- * We are matching on KEY_LEFTALT instead of KEY_SYSRQ because not all
- * keyboards have SysRq key predefined and so user may add it to keymap
- * later, but we expect all such keyboards to have left alt.
- */
-static const struct input_device_id sysrq_ids[] = {
- {
- .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
- INPUT_DEVICE_ID_MATCH_KEYBIT,
- .evbit = { BIT_MASK(EV_KEY) },
- .keybit = { BIT_MASK(KEY_LEFTALT) },
- },
- { },
-};
-
-static struct input_handler sysrq_handler = {
- .filter = sysrq_filter,
- .connect = sysrq_connect,
- .disconnect = sysrq_disconnect,
- .name = "sysrq",
- .id_table = sysrq_ids,
-};
-
-static bool sysrq_handler_registered;
-
-static inline void sysrq_register_handler(void)
-{
- int error;
-
- error = input_register_handler(&sysrq_handler);
- if (error)
- pr_err("Failed to register input handler, error %d", error);
- else
- sysrq_handler_registered = true;
-}
-
-static inline void sysrq_unregister_handler(void)
-{
- if (sysrq_handler_registered) {
- input_unregister_handler(&sysrq_handler);
- sysrq_handler_registered = false;
- }
-}
-
-#else
-
-static inline void sysrq_register_handler(void)
-{
-}
-
-static inline void sysrq_unregister_handler(void)
-{
-}
-
-#endif /* CONFIG_INPUT */
-
-int sysrq_toggle_support(int enable_mask)
-{
- bool was_enabled = sysrq_on();
-
- sysrq_enabled = enable_mask;
-
- if (was_enabled != sysrq_on()) {
- if (sysrq_on())
- sysrq_register_handler();
- else
- sysrq_unregister_handler();
- }
-
- return 0;
-}
-
-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);
-
-#ifdef CONFIG_PROC_FS
-/*
- * writing 'C' to /proc/sysrq-trigger is like sysrq-C
- */
-static ssize_t write_sysrq_trigger(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- if (count) {
- char c;
-
- if (get_user(c, buf))
- return -EFAULT;
- __handle_sysrq(c, false);
- }
-
- return count;
-}
-
-static const struct file_operations proc_sysrq_trigger_operations = {
- .write = write_sysrq_trigger,
- .llseek = noop_llseek,
-};
-
-static void sysrq_init_procfs(void)
-{
- if (!proc_create("sysrq-trigger", S_IWUSR, NULL,
- &proc_sysrq_trigger_operations))
- pr_err("Failed to register proc interface\n");
-}
-
-#else
-
-static inline void sysrq_init_procfs(void)
-{
-}
-
-#endif /* CONFIG_PROC_FS */
-
-static int __init sysrq_init(void)
-{
- sysrq_init_procfs();
-
- if (sysrq_on())
- sysrq_register_handler();
-
- return 0;
-}
-module_init(sysrq_init);
projects / mv-sheeva.git / blobdiff