]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/char/ipmi/ipmi_watchdog.c
Merge git://git.infradead.org/mtd-2.6
[linux-2.6-omap-h63xx.git] / drivers / char / ipmi / ipmi_watchdog.c
index 2da64bf7469c6963e008e6215c610dae78dd3e3a..8f8867170973ccb95960b57a90cd5e58dc9d5ddb 100644 (file)
@@ -39,6 +39,7 @@
 #include <linux/watchdog.h>
 #include <linux/miscdevice.h>
 #include <linux/init.h>
+#include <linux/completion.h>
 #include <linux/rwsem.h>
 #include <linux/errno.h>
 #include <asm/uaccess.h>
@@ -47,6 +48,9 @@
 #include <linux/reboot.h>
 #include <linux/wait.h>
 #include <linux/poll.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <asm/atomic.h>
 #ifdef CONFIG_X86_LOCAL_APIC
 #include <asm/apic.h>
 #endif
@@ -158,27 +162,113 @@ static struct fasync_struct *fasync_q = NULL;
 static char pretimeout_since_last_heartbeat = 0;
 static char expect_close;
 
+static DECLARE_RWSEM(register_sem);
+
+/* Parameters to ipmi_set_timeout */
+#define IPMI_SET_TIMEOUT_NO_HB                 0
+#define IPMI_SET_TIMEOUT_HB_IF_NECESSARY       1
+#define IPMI_SET_TIMEOUT_FORCE_HB              2
+
+static int ipmi_set_timeout(int do_heartbeat);
+
 /* If true, the driver will start running as soon as it is configured
    and ready. */
 static int start_now = 0;
 
-module_param(timeout, int, 0);
+static int set_param_int(const char *val, struct kernel_param *kp)
+{
+       char *endp;
+       int  l;
+       int  rv = 0;
+
+       if (!val)
+               return -EINVAL;
+       l = simple_strtoul(val, &endp, 0);
+       if (endp == val)
+               return -EINVAL;
+
+       down_read(&register_sem);
+       *((int *)kp->arg) = l;
+       if (watchdog_user)
+               rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY);
+       up_read(&register_sem);
+
+       return rv;
+}
+
+static int get_param_int(char *buffer, struct kernel_param *kp)
+{
+       return sprintf(buffer, "%i", *((int *)kp->arg));
+}
+
+typedef int (*action_fn)(const char *intval, char *outval);
+
+static int action_op(const char *inval, char *outval);
+static int preaction_op(const char *inval, char *outval);
+static int preop_op(const char *inval, char *outval);
+static void check_parms(void);
+
+static int set_param_str(const char *val, struct kernel_param *kp)
+{
+       action_fn  fn = (action_fn) kp->arg;
+       int        rv = 0;
+       char       *dup, *s;
+
+       dup = kstrdup(val, GFP_KERNEL);
+       if (!dup)
+               return -ENOMEM;
+
+       s = strstrip(dup);
+
+       down_read(&register_sem);
+       rv = fn(s, NULL);
+       if (rv)
+               goto out_unlock;
+
+       check_parms();
+       if (watchdog_user)
+               rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY);
+
+ out_unlock:
+       up_read(&register_sem);
+       kfree(dup);
+       return rv;
+}
+
+static int get_param_str(char *buffer, struct kernel_param *kp)
+{
+       action_fn fn = (action_fn) kp->arg;
+       int       rv;
+
+       rv = fn(NULL, buffer);
+       if (rv)
+               return rv;
+       return strlen(buffer);
+}
+
+module_param_call(timeout, set_param_int, get_param_int, &timeout, 0644);
 MODULE_PARM_DESC(timeout, "Timeout value in seconds.");
-module_param(pretimeout, int, 0);
+
+module_param_call(pretimeout, set_param_int, get_param_int, &pretimeout, 0644);
 MODULE_PARM_DESC(pretimeout, "Pretimeout value in seconds.");
-module_param_string(action, action, sizeof(action), 0);
+
+module_param_call(action, set_param_str, get_param_str, action_op, 0644);
 MODULE_PARM_DESC(action, "Timeout action. One of: "
                 "reset, none, power_cycle, power_off.");
-module_param_string(preaction, preaction, sizeof(preaction), 0);
+
+module_param_call(preaction, set_param_str, get_param_str, preaction_op, 0644);
 MODULE_PARM_DESC(preaction, "Pretimeout action.  One of: "
                 "pre_none, pre_smi, pre_nmi, pre_int.");
-module_param_string(preop, preop, sizeof(preop), 0);
+
+module_param_call(preop, set_param_str, get_param_str, preop_op, 0644);
 MODULE_PARM_DESC(preop, "Pretimeout driver operation.  One of: "
                 "preop_none, preop_panic, preop_give_data.");
+
 module_param(start_now, int, 0);
 MODULE_PARM_DESC(start_now, "Set to 1 to start the watchdog as"
                 "soon as the driver is loaded.");
-module_param(nowayout, int, 0);
+
+module_param(nowayout, int, 0644);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
 
 /* Default state of the timer. */
@@ -200,26 +290,29 @@ static int ipmi_start_timer_on_heartbeat = 0;
 static unsigned char ipmi_version_major;
 static unsigned char ipmi_version_minor;
 
+/* If a pretimeout occurs, this is used to allow only one panic to happen. */
+static atomic_t preop_panic_excl = ATOMIC_INIT(-1);
 
 static int ipmi_heartbeat(void);
 static void panic_halt_ipmi_heartbeat(void);
 
 
-/* We use a semaphore to make sure that only one thing can send a set
+/* We use a mutex to make sure that only one thing can send a set
    timeout at one time, because we only have one copy of the data.
-   The semaphore is claimed when the set_timeout is sent and freed
+   The mutex is claimed when the set_timeout is sent and freed
    when both messages are free. */
 static atomic_t set_timeout_tofree = ATOMIC_INIT(0);
-static DECLARE_MUTEX(set_timeout_lock);
+static DEFINE_MUTEX(set_timeout_lock);
+static DECLARE_COMPLETION(set_timeout_wait);
 static void set_timeout_free_smi(struct ipmi_smi_msg *msg)
 {
     if (atomic_dec_and_test(&set_timeout_tofree))
-           up(&set_timeout_lock);
+           complete(&set_timeout_wait);
 }
 static void set_timeout_free_recv(struct ipmi_recv_msg *msg)
 {
     if (atomic_dec_and_test(&set_timeout_tofree))
-           up(&set_timeout_lock);
+           complete(&set_timeout_wait);
 }
 static struct ipmi_smi_msg set_timeout_smi_msg =
 {
@@ -294,11 +387,6 @@ static int i_ipmi_set_timeout(struct ipmi_smi_msg  *smi_msg,
        return rv;
 }
 
-/* Parameters to ipmi_set_timeout */
-#define IPMI_SET_TIMEOUT_NO_HB                 0
-#define IPMI_SET_TIMEOUT_HB_IF_NECESSARY       1
-#define IPMI_SET_TIMEOUT_FORCE_HB              2
-
 static int ipmi_set_timeout(int do_heartbeat)
 {
        int send_heartbeat_now;
@@ -306,7 +394,7 @@ static int ipmi_set_timeout(int do_heartbeat)
 
 
        /* We can only send one of these at a time. */
-       down(&set_timeout_lock);
+       mutex_lock(&set_timeout_lock);
 
        atomic_set(&set_timeout_tofree, 2);
 
@@ -314,16 +402,21 @@ static int ipmi_set_timeout(int do_heartbeat)
                                &set_timeout_recv_msg,
                                &send_heartbeat_now);
        if (rv) {
-               up(&set_timeout_lock);
-       } else {
-               if ((do_heartbeat == IPMI_SET_TIMEOUT_FORCE_HB)
-                   || ((send_heartbeat_now)
-                       && (do_heartbeat == IPMI_SET_TIMEOUT_HB_IF_NECESSARY)))
-               {
-                       rv = ipmi_heartbeat();
-               }
+               mutex_unlock(&set_timeout_lock);
+               goto out;
        }
 
+       wait_for_completion(&set_timeout_wait);
+
+       if ((do_heartbeat == IPMI_SET_TIMEOUT_FORCE_HB)
+           || ((send_heartbeat_now)
+               && (do_heartbeat == IPMI_SET_TIMEOUT_HB_IF_NECESSARY)))
+       {
+               rv = ipmi_heartbeat();
+       }
+       mutex_unlock(&set_timeout_lock);
+
+out:
        return rv;
 }
 
@@ -365,17 +458,17 @@ static void panic_halt_ipmi_set_timeout(void)
    The semaphore is claimed when the set_timeout is sent and freed
    when both messages are free. */
 static atomic_t heartbeat_tofree = ATOMIC_INIT(0);
-static DECLARE_MUTEX(heartbeat_lock);
-static DECLARE_MUTEX_LOCKED(heartbeat_wait_lock);
+static DEFINE_MUTEX(heartbeat_lock);
+static DECLARE_COMPLETION(heartbeat_wait);
 static void heartbeat_free_smi(struct ipmi_smi_msg *msg)
 {
     if (atomic_dec_and_test(&heartbeat_tofree))
-           up(&heartbeat_wait_lock);
+           complete(&heartbeat_wait);
 }
 static void heartbeat_free_recv(struct ipmi_recv_msg *msg)
 {
     if (atomic_dec_and_test(&heartbeat_tofree))
-           up(&heartbeat_wait_lock);
+           complete(&heartbeat_wait);
 }
 static struct ipmi_smi_msg heartbeat_smi_msg =
 {
@@ -418,14 +511,14 @@ static int ipmi_heartbeat(void)
                return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY);
        }
 
-       down(&heartbeat_lock);
+       mutex_lock(&heartbeat_lock);
 
        atomic_set(&heartbeat_tofree, 2);
 
        /* Don't reset the timer if we have the timer turned off, that
            re-enables the watchdog. */
        if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE) {
-               up(&heartbeat_lock);
+               mutex_unlock(&heartbeat_lock);
                return 0;
        }
 
@@ -446,14 +539,14 @@ static int ipmi_heartbeat(void)
                                      &heartbeat_recv_msg,
                                      1);
        if (rv) {
-               up(&heartbeat_lock);
+               mutex_unlock(&heartbeat_lock);
                printk(KERN_WARNING PFX "heartbeat failure: %d\n",
                       rv);
                return rv;
        }
 
        /* Wait for the heartbeat to be sent. */
-       down(&heartbeat_wait_lock);
+       wait_for_completion(&heartbeat_wait);
 
        if (heartbeat_recv_msg.msg.data[0] != 0) {
            /* Got an error in the heartbeat response.  It was already
@@ -462,7 +555,7 @@ static int ipmi_heartbeat(void)
            rv = -EINVAL;
        }
 
-       up(&heartbeat_lock);
+       mutex_unlock(&heartbeat_lock);
 
        return rv;
 }
@@ -496,7 +589,7 @@ static void panic_halt_ipmi_heartbeat(void)
                                 1);
 }
 
-static struct watchdog_info ident=
+static struct watchdog_info ident =
 {
        .options        = 0,    /* WDIOF_SETTIMEOUT, */
        .firmware_version = 1,
@@ -697,13 +790,13 @@ static int ipmi_fasync(int fd, struct file *file, int on)
 
 static int ipmi_close(struct inode *ino, struct file *filep)
 {
-       if (iminor(ino)==WATCHDOG_MINOR)
-       {
+       if (iminor(ino) == WATCHDOG_MINOR) {
                if (expect_close == 42) {
                        ipmi_watchdog_state = WDOG_TIMEOUT_NONE;
                        ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB);
                } else {
-                       printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
+                       printk(KERN_CRIT PFX
+                              "Unexpected close, not stopping watchdog!\n");
                        ipmi_heartbeat();
                }
                clear_bit(0, &ipmi_wdog_open);
@@ -732,8 +825,6 @@ static struct miscdevice ipmi_wdog_miscdev = {
        .fops           = &ipmi_wdog_fops
 };
 
-static DECLARE_RWSEM(register_sem);
-
 static void ipmi_wdog_msg_handler(struct ipmi_recv_msg *msg,
                                  void                 *handler_data)
 {
@@ -749,9 +840,10 @@ static void ipmi_wdog_msg_handler(struct ipmi_recv_msg *msg,
 static void ipmi_wdog_pretimeout_handler(void *handler_data)
 {
        if (preaction_val != WDOG_PRETIMEOUT_NONE) {
-               if (preop_val == WDOG_PREOP_PANIC)
-                       panic("Watchdog pre-timeout");
-               else if (preop_val == WDOG_PREOP_GIVE_DATA) {
+               if (preop_val == WDOG_PREOP_PANIC) {
+                       if (atomic_inc_and_test(&preop_panic_excl))
+                               panic("Watchdog pre-timeout");
+               } else if (preop_val == WDOG_PREOP_GIVE_DATA) {
                        spin_lock(&ipmi_read_lock);
                        data_to_read = 1;
                        wake_up_interruptible(&read_q);
@@ -825,7 +917,8 @@ ipmi_nmi(void *dev_id, struct pt_regs *regs, int cpu, int handled)
                   an error and not work unless we re-enable
                   the timer.   So do so. */
                pretimeout_since_last_heartbeat = 1;
-               panic(PFX "pre-timeout");
+               if (atomic_inc_and_test(&preop_panic_excl))
+                       panic(PFX "pre-timeout");
        }
 
        return NOTIFY_DONE;
@@ -839,6 +932,7 @@ static struct nmi_handler ipmi_nmi_handler =
        .handler  = ipmi_nmi,
        .priority = 0, /* Call us last. */
 };
+int nmi_handler_registered;
 #endif
 
 static int wdog_reboot_handler(struct notifier_block *this,
@@ -902,7 +996,7 @@ static struct notifier_block wdog_panic_notifier = {
 };
 
 
-static void ipmi_new_smi(int if_num)
+static void ipmi_new_smi(int if_num, struct device *device)
 {
        ipmi_register_watchdog(if_num);
 }
@@ -921,59 +1015,86 @@ static struct ipmi_smi_watcher smi_watcher =
        .smi_gone = ipmi_smi_gone
 };
 
-static int __init ipmi_wdog_init(void)
+static int action_op(const char *inval, char *outval)
 {
-       int rv;
+       if (outval)
+               strcpy(outval, action);
 
-       if (strcmp(action, "reset") == 0) {
+       if (!inval)
+               return 0;
+
+       if (strcmp(inval, "reset") == 0)
                action_val = WDOG_TIMEOUT_RESET;
-       } else if (strcmp(action, "none") == 0) {
+       else if (strcmp(inval, "none") == 0)
                action_val = WDOG_TIMEOUT_NONE;
-       } else if (strcmp(action, "power_cycle") == 0) {
+       else if (strcmp(inval, "power_cycle") == 0)
                action_val = WDOG_TIMEOUT_POWER_CYCLE;
-       } else if (strcmp(action, "power_off") == 0) {
+       else if (strcmp(inval, "power_off") == 0)
                action_val = WDOG_TIMEOUT_POWER_DOWN;
-       } else {
-               action_val = WDOG_TIMEOUT_RESET;
-               printk(KERN_INFO PFX "Unknown action '%s', defaulting to"
-                      " reset\n", action);
-       }
+       else
+               return -EINVAL;
+       strcpy(action, inval);
+       return 0;
+}
 
-       if (strcmp(preaction, "pre_none") == 0) {
+static int preaction_op(const char *inval, char *outval)
+{
+       if (outval)
+               strcpy(outval, preaction);
+
+       if (!inval)
+               return 0;
+
+       if (strcmp(inval, "pre_none") == 0)
                preaction_val = WDOG_PRETIMEOUT_NONE;
-       } else if (strcmp(preaction, "pre_smi") == 0) {
+       else if (strcmp(inval, "pre_smi") == 0)
                preaction_val = WDOG_PRETIMEOUT_SMI;
 #ifdef HAVE_NMI_HANDLER
-       } else if (strcmp(preaction, "pre_nmi") == 0) {
+       else if (strcmp(inval, "pre_nmi") == 0)
                preaction_val = WDOG_PRETIMEOUT_NMI;
 #endif
-       } else if (strcmp(preaction, "pre_int") == 0) {
+       else if (strcmp(inval, "pre_int") == 0)
                preaction_val = WDOG_PRETIMEOUT_MSG_INT;
-       } else {
-               preaction_val = WDOG_PRETIMEOUT_NONE;
-               printk(KERN_INFO PFX "Unknown preaction '%s', defaulting to"
-                      " none\n", preaction);
-       }
+       else
+               return -EINVAL;
+       strcpy(preaction, inval);
+       return 0;
+}
+
+static int preop_op(const char *inval, char *outval)
+{
+       if (outval)
+               strcpy(outval, preop);
+
+       if (!inval)
+               return 0;
 
-       if (strcmp(preop, "preop_none") == 0) {
+       if (strcmp(inval, "preop_none") == 0)
                preop_val = WDOG_PREOP_NONE;
-       } else if (strcmp(preop, "preop_panic") == 0) {
+       else if (strcmp(inval, "preop_panic") == 0)
                preop_val = WDOG_PREOP_PANIC;
-       } else if (strcmp(preop, "preop_give_data") == 0) {
+       else if (strcmp(inval, "preop_give_data") == 0)
                preop_val = WDOG_PREOP_GIVE_DATA;
-       } else {
-               preop_val = WDOG_PREOP_NONE;
-               printk(KERN_INFO PFX "Unknown preop '%s', defaulting to"
-                      " none\n", preop);
-       }
+       else
+               return -EINVAL;
+       strcpy(preop, inval);
+       return 0;
+}
 
+static void check_parms(void)
+{
 #ifdef HAVE_NMI_HANDLER
+       int do_nmi = 0;
+       int rv;
+
        if (preaction_val == WDOG_PRETIMEOUT_NMI) {
+               do_nmi = 1;
                if (preop_val == WDOG_PREOP_GIVE_DATA) {
                        printk(KERN_WARNING PFX "Pretimeout op is to give data"
                               " but NMI pretimeout is enabled, setting"
                               " pretimeout op to none\n");
-                       preop_val = WDOG_PREOP_NONE;
+                       preop_op("preop_none", NULL);
+                       do_nmi = 0;
                }
 #ifdef CONFIG_X86_LOCAL_APIC
                if (nmi_watchdog == NMI_IO_APIC) {
@@ -983,18 +1104,48 @@ static int __init ipmi_wdog_init(void)
                               " Disabling IPMI nmi pretimeout.\n",
                               nmi_watchdog);
                        preaction_val = WDOG_PRETIMEOUT_NONE;
-               } else {
+                       do_nmi = 0;
+               }
 #endif
+       }
+       if (do_nmi && !nmi_handler_registered) {
                rv = request_nmi(&ipmi_nmi_handler);
                if (rv) {
-                       printk(KERN_WARNING PFX "Can't register nmi handler\n");
-                       return rv;
-               }
-#ifdef CONFIG_X86_LOCAL_APIC
-               }
-#endif
+                       printk(KERN_WARNING PFX
+                              "Can't register nmi handler\n");
+                       return;
+               } else
+                       nmi_handler_registered = 1;
+       } else if (!do_nmi && nmi_handler_registered) {
+               release_nmi(&ipmi_nmi_handler);
+               nmi_handler_registered = 0;
        }
 #endif
+}
+
+static int __init ipmi_wdog_init(void)
+{
+       int rv;
+
+       if (action_op(action, NULL)) {
+               action_op("reset", NULL);
+               printk(KERN_INFO PFX "Unknown action '%s', defaulting to"
+                      " reset\n", action);
+       }
+
+       if (preaction_op(preaction, NULL)) {
+               preaction_op("pre_none", NULL);
+               printk(KERN_INFO PFX "Unknown preaction '%s', defaulting to"
+                      " none\n", preaction);
+       }
+
+       if (preop_op(preop, NULL)) {
+               preop_op("preop_none", NULL);
+               printk(KERN_INFO PFX "Unknown preop '%s', defaulting to"
+                      " none\n", preop);
+       }
+
+       check_parms();
 
        rv = ipmi_smi_watcher_register(&smi_watcher);
        if (rv) {
@@ -1007,7 +1158,8 @@ static int __init ipmi_wdog_init(void)
        }
 
        register_reboot_notifier(&wdog_reboot_notifier);
-       notifier_chain_register(&panic_notifier_list, &wdog_panic_notifier);
+       atomic_notifier_chain_register(&panic_notifier_list,
+                       &wdog_panic_notifier);
 
        printk(KERN_INFO PFX "driver initialized\n");
 
@@ -1021,11 +1173,12 @@ static __exit void ipmi_unregister_watchdog(void)
        down_write(&register_sem);
 
 #ifdef HAVE_NMI_HANDLER
-       if (preaction_val == WDOG_PRETIMEOUT_NMI)
+       if (nmi_handler_registered)
                release_nmi(&ipmi_nmi_handler);
 #endif
 
-       notifier_chain_unregister(&panic_notifier_list, &wdog_panic_notifier);
+       atomic_notifier_chain_unregister(&panic_notifier_list,
+                       &wdog_panic_notifier);
        unregister_reboot_notifier(&wdog_reboot_notifier);
 
        if (! watchdog_user)