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path: root/drivers/char/ipmi/ipmi_watchdog.c
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Diffstat (limited to 'drivers/char/ipmi/ipmi_watchdog.c')
-rw-r--r--drivers/char/ipmi/ipmi_watchdog.c1068
1 files changed, 1068 insertions, 0 deletions
diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c
new file mode 100644
index 000000000000..fd7093879c66
--- /dev/null
+++ b/drivers/char/ipmi/ipmi_watchdog.c
@@ -0,0 +1,1068 @@
+/*
+ * ipmi_watchdog.c
+ *
+ * A watchdog timer based upon the IPMI interface.
+ *
+ * Author: MontaVista Software, Inc.
+ * Corey Minyard <minyard@mvista.com>
+ * source@mvista.com
+ *
+ * Copyright 2002 MontaVista Software Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+ * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/ipmi.h>
+#include <linux/ipmi_smi.h>
+#include <linux/watchdog.h>
+#include <linux/miscdevice.h>
+#include <linux/init.h>
+#include <linux/rwsem.h>
+#include <linux/errno.h>
+#include <asm/uaccess.h>
+#include <linux/notifier.h>
+#include <linux/nmi.h>
+#include <linux/reboot.h>
+#include <linux/wait.h>
+#include <linux/poll.h>
+#ifdef CONFIG_X86_LOCAL_APIC
+#include <asm/apic.h>
+#endif
+
+#define PFX "IPMI Watchdog: "
+
+#define IPMI_WATCHDOG_VERSION "v33"
+
+/*
+ * The IPMI command/response information for the watchdog timer.
+ */
+
+/* values for byte 1 of the set command, byte 2 of the get response. */
+#define WDOG_DONT_LOG (1 << 7)
+#define WDOG_DONT_STOP_ON_SET (1 << 6)
+#define WDOG_SET_TIMER_USE(byte, use) \
+ byte = ((byte) & 0xf8) | ((use) & 0x7)
+#define WDOG_GET_TIMER_USE(byte) ((byte) & 0x7)
+#define WDOG_TIMER_USE_BIOS_FRB2 1
+#define WDOG_TIMER_USE_BIOS_POST 2
+#define WDOG_TIMER_USE_OS_LOAD 3
+#define WDOG_TIMER_USE_SMS_OS 4
+#define WDOG_TIMER_USE_OEM 5
+
+/* values for byte 2 of the set command, byte 3 of the get response. */
+#define WDOG_SET_PRETIMEOUT_ACT(byte, use) \
+ byte = ((byte) & 0x8f) | (((use) & 0x7) << 4)
+#define WDOG_GET_PRETIMEOUT_ACT(byte) (((byte) >> 4) & 0x7)
+#define WDOG_PRETIMEOUT_NONE 0
+#define WDOG_PRETIMEOUT_SMI 1
+#define WDOG_PRETIMEOUT_NMI 2
+#define WDOG_PRETIMEOUT_MSG_INT 3
+
+/* Operations that can be performed on a pretimout. */
+#define WDOG_PREOP_NONE 0
+#define WDOG_PREOP_PANIC 1
+#define WDOG_PREOP_GIVE_DATA 2 /* Cause data to be available to
+ read. Doesn't work in NMI
+ mode. */
+
+/* Actions to perform on a full timeout. */
+#define WDOG_SET_TIMEOUT_ACT(byte, use) \
+ byte = ((byte) & 0xf8) | ((use) & 0x7)
+#define WDOG_GET_TIMEOUT_ACT(byte) ((byte) & 0x7)
+#define WDOG_TIMEOUT_NONE 0
+#define WDOG_TIMEOUT_RESET 1
+#define WDOG_TIMEOUT_POWER_DOWN 2
+#define WDOG_TIMEOUT_POWER_CYCLE 3
+
+/* Byte 3 of the get command, byte 4 of the get response is the
+ pre-timeout in seconds. */
+
+/* Bits for setting byte 4 of the set command, byte 5 of the get response. */
+#define WDOG_EXPIRE_CLEAR_BIOS_FRB2 (1 << 1)
+#define WDOG_EXPIRE_CLEAR_BIOS_POST (1 << 2)
+#define WDOG_EXPIRE_CLEAR_OS_LOAD (1 << 3)
+#define WDOG_EXPIRE_CLEAR_SMS_OS (1 << 4)
+#define WDOG_EXPIRE_CLEAR_OEM (1 << 5)
+
+/* Setting/getting the watchdog timer value. This is for bytes 5 and
+ 6 (the timeout time) of the set command, and bytes 6 and 7 (the
+ timeout time) and 8 and 9 (the current countdown value) of the
+ response. The timeout value is given in seconds (in the command it
+ is 100ms intervals). */
+#define WDOG_SET_TIMEOUT(byte1, byte2, val) \
+ (byte1) = (((val) * 10) & 0xff), (byte2) = (((val) * 10) >> 8)
+#define WDOG_GET_TIMEOUT(byte1, byte2) \
+ (((byte1) | ((byte2) << 8)) / 10)
+
+#define IPMI_WDOG_RESET_TIMER 0x22
+#define IPMI_WDOG_SET_TIMER 0x24
+#define IPMI_WDOG_GET_TIMER 0x25
+
+/* These are here until the real ones get into the watchdog.h interface. */
+#ifndef WDIOC_GETTIMEOUT
+#define WDIOC_GETTIMEOUT _IOW(WATCHDOG_IOCTL_BASE, 20, int)
+#endif
+#ifndef WDIOC_SET_PRETIMEOUT
+#define WDIOC_SET_PRETIMEOUT _IOW(WATCHDOG_IOCTL_BASE, 21, int)
+#endif
+#ifndef WDIOC_GET_PRETIMEOUT
+#define WDIOC_GET_PRETIMEOUT _IOW(WATCHDOG_IOCTL_BASE, 22, int)
+#endif
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+static int nowayout = 1;
+#else
+static int nowayout;
+#endif
+
+static ipmi_user_t watchdog_user = NULL;
+
+/* Default the timeout to 10 seconds. */
+static int timeout = 10;
+
+/* The pre-timeout is disabled by default. */
+static int pretimeout = 0;
+
+/* Default action is to reset the board on a timeout. */
+static unsigned char action_val = WDOG_TIMEOUT_RESET;
+
+static char action[16] = "reset";
+
+static unsigned char preaction_val = WDOG_PRETIMEOUT_NONE;
+
+static char preaction[16] = "pre_none";
+
+static unsigned char preop_val = WDOG_PREOP_NONE;
+
+static char preop[16] = "preop_none";
+static DEFINE_SPINLOCK(ipmi_read_lock);
+static char data_to_read = 0;
+static DECLARE_WAIT_QUEUE_HEAD(read_q);
+static struct fasync_struct *fasync_q = NULL;
+static char pretimeout_since_last_heartbeat = 0;
+static char expect_close;
+
+/* 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);
+MODULE_PARM_DESC(timeout, "Timeout value in seconds.");
+module_param(pretimeout, int, 0);
+MODULE_PARM_DESC(pretimeout, "Pretimeout value in seconds.");
+module_param_string(action, action, sizeof(action), 0);
+MODULE_PARM_DESC(action, "Timeout action. One of: "
+ "reset, none, power_cycle, power_off.");
+module_param_string(preaction, preaction, sizeof(preaction), 0);
+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_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_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
+
+/* Default state of the timer. */
+static unsigned char ipmi_watchdog_state = WDOG_TIMEOUT_NONE;
+
+/* If shutting down via IPMI, we ignore the heartbeat. */
+static int ipmi_ignore_heartbeat = 0;
+
+/* Is someone using the watchdog? Only one user is allowed. */
+static unsigned long ipmi_wdog_open = 0;
+
+/* If set to 1, the heartbeat command will set the state to reset and
+ start the timer. The timer doesn't normally run when the driver is
+ first opened until the heartbeat is set the first time, this
+ variable is used to accomplish this. */
+static int ipmi_start_timer_on_heartbeat = 0;
+
+/* IPMI version of the BMC. */
+static unsigned char ipmi_version_major;
+static unsigned char ipmi_version_minor;
+
+
+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
+ 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
+ when both messages are free. */
+static atomic_t set_timeout_tofree = ATOMIC_INIT(0);
+static DECLARE_MUTEX(set_timeout_lock);
+static void set_timeout_free_smi(struct ipmi_smi_msg *msg)
+{
+ if (atomic_dec_and_test(&set_timeout_tofree))
+ up(&set_timeout_lock);
+}
+static void set_timeout_free_recv(struct ipmi_recv_msg *msg)
+{
+ if (atomic_dec_and_test(&set_timeout_tofree))
+ up(&set_timeout_lock);
+}
+static struct ipmi_smi_msg set_timeout_smi_msg =
+{
+ .done = set_timeout_free_smi
+};
+static struct ipmi_recv_msg set_timeout_recv_msg =
+{
+ .done = set_timeout_free_recv
+};
+
+static int i_ipmi_set_timeout(struct ipmi_smi_msg *smi_msg,
+ struct ipmi_recv_msg *recv_msg,
+ int *send_heartbeat_now)
+{
+ struct kernel_ipmi_msg msg;
+ unsigned char data[6];
+ int rv;
+ struct ipmi_system_interface_addr addr;
+ int hbnow = 0;
+
+
+ data[0] = 0;
+ WDOG_SET_TIMER_USE(data[0], WDOG_TIMER_USE_SMS_OS);
+
+ if ((ipmi_version_major > 1)
+ || ((ipmi_version_major == 1) && (ipmi_version_minor >= 5)))
+ {
+ /* This is an IPMI 1.5-only feature. */
+ data[0] |= WDOG_DONT_STOP_ON_SET;
+ } else if (ipmi_watchdog_state != WDOG_TIMEOUT_NONE) {
+ /* In ipmi 1.0, setting the timer stops the watchdog, we
+ need to start it back up again. */
+ hbnow = 1;
+ }
+
+ data[1] = 0;
+ WDOG_SET_TIMEOUT_ACT(data[1], ipmi_watchdog_state);
+ if (pretimeout > 0) {
+ WDOG_SET_PRETIMEOUT_ACT(data[1], preaction_val);
+ data[2] = pretimeout;
+ } else {
+ WDOG_SET_PRETIMEOUT_ACT(data[1], WDOG_PRETIMEOUT_NONE);
+ data[2] = 0; /* No pretimeout. */
+ }
+ data[3] = 0;
+ WDOG_SET_TIMEOUT(data[4], data[5], timeout);
+
+ addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+ addr.channel = IPMI_BMC_CHANNEL;
+ addr.lun = 0;
+
+ msg.netfn = 0x06;
+ msg.cmd = IPMI_WDOG_SET_TIMER;
+ msg.data = data;
+ msg.data_len = sizeof(data);
+ rv = ipmi_request_supply_msgs(watchdog_user,
+ (struct ipmi_addr *) &addr,
+ 0,
+ &msg,
+ NULL,
+ smi_msg,
+ recv_msg,
+ 1);
+ if (rv) {
+ printk(KERN_WARNING PFX "set timeout error: %d\n",
+ rv);
+ }
+
+ if (send_heartbeat_now)
+ *send_heartbeat_now = hbnow;
+
+ 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;
+ int rv;
+
+
+ /* We can only send one of these at a time. */
+ down(&set_timeout_lock);
+
+ atomic_set(&set_timeout_tofree, 2);
+
+ rv = i_ipmi_set_timeout(&set_timeout_smi_msg,
+ &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();
+ }
+ }
+
+ return rv;
+}
+
+static void dummy_smi_free(struct ipmi_smi_msg *msg)
+{
+}
+static void dummy_recv_free(struct ipmi_recv_msg *msg)
+{
+}
+static struct ipmi_smi_msg panic_halt_smi_msg =
+{
+ .done = dummy_smi_free
+};
+static struct ipmi_recv_msg panic_halt_recv_msg =
+{
+ .done = dummy_recv_free
+};
+
+/* Special call, doesn't claim any locks. This is only to be called
+ at panic or halt time, in run-to-completion mode, when the caller
+ is the only CPU and the only thing that will be going is these IPMI
+ calls. */
+static void panic_halt_ipmi_set_timeout(void)
+{
+ int send_heartbeat_now;
+ int rv;
+
+ rv = i_ipmi_set_timeout(&panic_halt_smi_msg,
+ &panic_halt_recv_msg,
+ &send_heartbeat_now);
+ if (!rv) {
+ if (send_heartbeat_now)
+ panic_halt_ipmi_heartbeat();
+ }
+}
+
+/* We use a semaphore to make sure that only one thing can send a
+ heartbeat at one time, because we only have one copy of the data.
+ 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 void heartbeat_free_smi(struct ipmi_smi_msg *msg)
+{
+ if (atomic_dec_and_test(&heartbeat_tofree))
+ up(&heartbeat_wait_lock);
+}
+static void heartbeat_free_recv(struct ipmi_recv_msg *msg)
+{
+ if (atomic_dec_and_test(&heartbeat_tofree))
+ up(&heartbeat_wait_lock);
+}
+static struct ipmi_smi_msg heartbeat_smi_msg =
+{
+ .done = heartbeat_free_smi
+};
+static struct ipmi_recv_msg heartbeat_recv_msg =
+{
+ .done = heartbeat_free_recv
+};
+
+static struct ipmi_smi_msg panic_halt_heartbeat_smi_msg =
+{
+ .done = dummy_smi_free
+};
+static struct ipmi_recv_msg panic_halt_heartbeat_recv_msg =
+{
+ .done = dummy_recv_free
+};
+
+static int ipmi_heartbeat(void)
+{
+ struct kernel_ipmi_msg msg;
+ int rv;
+ struct ipmi_system_interface_addr addr;
+
+ if (ipmi_ignore_heartbeat) {
+ return 0;
+ }
+
+ if (ipmi_start_timer_on_heartbeat) {
+ ipmi_start_timer_on_heartbeat = 0;
+ ipmi_watchdog_state = action_val;
+ return ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB);
+ } else if (pretimeout_since_last_heartbeat) {
+ /* A pretimeout occurred, make sure we set the timeout.
+ We don't want to set the action, though, we want to
+ leave that alone (thus it can't be combined with the
+ above operation. */
+ pretimeout_since_last_heartbeat = 0;
+ return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY);
+ }
+
+ down(&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);
+ return 0;
+ }
+
+ addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+ addr.channel = IPMI_BMC_CHANNEL;
+ addr.lun = 0;
+
+ msg.netfn = 0x06;
+ msg.cmd = IPMI_WDOG_RESET_TIMER;
+ msg.data = NULL;
+ msg.data_len = 0;
+ rv = ipmi_request_supply_msgs(watchdog_user,
+ (struct ipmi_addr *) &addr,
+ 0,
+ &msg,
+ NULL,
+ &heartbeat_smi_msg,
+ &heartbeat_recv_msg,
+ 1);
+ if (rv) {
+ up(&heartbeat_lock);
+ printk(KERN_WARNING PFX "heartbeat failure: %d\n",
+ rv);
+ return rv;
+ }
+
+ /* Wait for the heartbeat to be sent. */
+ down(&heartbeat_wait_lock);
+
+ if (heartbeat_recv_msg.msg.data[0] != 0) {
+ /* Got an error in the heartbeat response. It was already
+ reported in ipmi_wdog_msg_handler, but we should return
+ an error here. */
+ rv = -EINVAL;
+ }
+
+ up(&heartbeat_lock);
+
+ return rv;
+}
+
+static void panic_halt_ipmi_heartbeat(void)
+{
+ struct kernel_ipmi_msg msg;
+ struct ipmi_system_interface_addr addr;
+
+
+ /* Don't reset the timer if we have the timer turned off, that
+ re-enables the watchdog. */
+ if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE)
+ return;
+
+ addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+ addr.channel = IPMI_BMC_CHANNEL;
+ addr.lun = 0;
+
+ msg.netfn = 0x06;
+ msg.cmd = IPMI_WDOG_RESET_TIMER;
+ msg.data = NULL;
+ msg.data_len = 0;
+ ipmi_request_supply_msgs(watchdog_user,
+ (struct ipmi_addr *) &addr,
+ 0,
+ &msg,
+ NULL,
+ &panic_halt_heartbeat_smi_msg,
+ &panic_halt_heartbeat_recv_msg,
+ 1);
+}
+
+static struct watchdog_info ident=
+{
+ .options = 0, /* WDIOF_SETTIMEOUT, */
+ .firmware_version = 1,
+ .identity = "IPMI"
+};
+
+static int ipmi_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ int i;
+ int val;
+
+ switch(cmd) {
+ case WDIOC_GETSUPPORT:
+ i = copy_to_user(argp, &ident, sizeof(ident));
+ return i ? -EFAULT : 0;
+
+ case WDIOC_SETTIMEOUT:
+ i = copy_from_user(&val, argp, sizeof(int));
+ if (i)
+ return -EFAULT;
+ timeout = val;
+ return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY);
+
+ case WDIOC_GETTIMEOUT:
+ i = copy_to_user(argp, &timeout, sizeof(timeout));
+ if (i)
+ return -EFAULT;
+ return 0;
+
+ case WDIOC_SET_PRETIMEOUT:
+ i = copy_from_user(&val, argp, sizeof(int));
+ if (i)
+ return -EFAULT;
+ pretimeout = val;
+ return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY);
+
+ case WDIOC_GET_PRETIMEOUT:
+ i = copy_to_user(argp, &pretimeout, sizeof(pretimeout));
+ if (i)
+ return -EFAULT;
+ return 0;
+
+ case WDIOC_KEEPALIVE:
+ return ipmi_heartbeat();
+
+ case WDIOC_SETOPTIONS:
+ i = copy_from_user(&val, argp, sizeof(int));
+ if (i)
+ return -EFAULT;
+ if (val & WDIOS_DISABLECARD)
+ {
+ ipmi_watchdog_state = WDOG_TIMEOUT_NONE;
+ ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB);
+ ipmi_start_timer_on_heartbeat = 0;
+ }
+
+ if (val & WDIOS_ENABLECARD)
+ {
+ ipmi_watchdog_state = action_val;
+ ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB);
+ }
+ return 0;
+
+ case WDIOC_GETSTATUS:
+ val = 0;
+ i = copy_to_user(argp, &val, sizeof(val));
+ if (i)
+ return -EFAULT;
+ return 0;
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static ssize_t ipmi_write(struct file *file,
+ const char __user *buf,
+ size_t len,
+ loff_t *ppos)
+{
+ int rv;
+
+ if (len) {
+ if (!nowayout) {
+ size_t i;
+
+ /* In case it was set long ago */
+ expect_close = 0;
+
+ for (i = 0; i != len; i++) {
+ char c;
+
+ if (get_user(c, buf + i))
+ return -EFAULT;
+ if (c == 'V')
+ expect_close = 42;
+ }
+ }
+ rv = ipmi_heartbeat();
+ if (rv)
+ return rv;
+ return 1;
+ }
+ return 0;
+}
+
+static ssize_t ipmi_read(struct file *file,
+ char __user *buf,
+ size_t count,
+ loff_t *ppos)
+{
+ int rv = 0;
+ wait_queue_t wait;
+
+ if (count <= 0)
+ return 0;
+
+ /* Reading returns if the pretimeout has gone off, and it only does
+ it once per pretimeout. */
+ spin_lock(&ipmi_read_lock);
+ if (!data_to_read) {
+ if (file->f_flags & O_NONBLOCK) {
+ rv = -EAGAIN;
+ goto out;
+ }
+
+ init_waitqueue_entry(&wait, current);
+ add_wait_queue(&read_q, &wait);
+ while (!data_to_read) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ spin_unlock(&ipmi_read_lock);
+ schedule();
+ spin_lock(&ipmi_read_lock);
+ }
+ remove_wait_queue(&read_q, &wait);
+
+ if (signal_pending(current)) {
+ rv = -ERESTARTSYS;
+ goto out;
+ }
+ }
+ data_to_read = 0;
+
+ out:
+ spin_unlock(&ipmi_read_lock);
+
+ if (rv == 0) {
+ if (copy_to_user(buf, &data_to_read, 1))
+ rv = -EFAULT;
+ else
+ rv = 1;
+ }
+
+ return rv;
+}
+
+static int ipmi_open(struct inode *ino, struct file *filep)
+{
+ switch (iminor(ino))
+ {
+ case WATCHDOG_MINOR:
+ if(test_and_set_bit(0, &ipmi_wdog_open))
+ return -EBUSY;
+
+ /* Don't start the timer now, let it start on the
+ first heartbeat. */
+ ipmi_start_timer_on_heartbeat = 1;
+ return nonseekable_open(ino, filep);
+
+ default:
+ return (-ENODEV);
+ }
+}
+
+static unsigned int ipmi_poll(struct file *file, poll_table *wait)
+{
+ unsigned int mask = 0;
+
+ poll_wait(file, &read_q, wait);
+
+ spin_lock(&ipmi_read_lock);
+ if (data_to_read)
+ mask |= (POLLIN | POLLRDNORM);
+ spin_unlock(&ipmi_read_lock);
+
+ return mask;
+}
+
+static int ipmi_fasync(int fd, struct file *file, int on)
+{
+ int result;
+
+ result = fasync_helper(fd, file, on, &fasync_q);
+
+ return (result);
+}
+
+static int ipmi_close(struct inode *ino, struct file *filep)
+{
+ if (iminor(ino)==WATCHDOG_MINOR)
+ {
+ if (expect_close == 42) {
+ ipmi_watchdog_state = WDOG_TIMEOUT_NONE;
+ ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB);
+ clear_bit(0, &ipmi_wdog_open);
+ } else {
+ printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
+ ipmi_heartbeat();
+ }
+ }
+
+ ipmi_fasync (-1, filep, 0);
+ expect_close = 0;
+
+ return 0;
+}
+
+static struct file_operations ipmi_wdog_fops = {
+ .owner = THIS_MODULE,
+ .read = ipmi_read,
+ .poll = ipmi_poll,
+ .write = ipmi_write,
+ .ioctl = ipmi_ioctl,
+ .open = ipmi_open,
+ .release = ipmi_close,
+ .fasync = ipmi_fasync,
+};
+
+static struct miscdevice ipmi_wdog_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &ipmi_wdog_fops
+};
+
+static DECLARE_RWSEM(register_sem);
+
+static void ipmi_wdog_msg_handler(struct ipmi_recv_msg *msg,
+ void *handler_data)
+{
+ if (msg->msg.data[0] != 0) {
+ printk(KERN_ERR PFX "response: Error %x on cmd %x\n",
+ msg->msg.data[0],
+ msg->msg.cmd);
+ }
+
+ ipmi_free_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) {
+ spin_lock(&ipmi_read_lock);
+ data_to_read = 1;
+ wake_up_interruptible(&read_q);
+ kill_fasync(&fasync_q, SIGIO, POLL_IN);
+
+ spin_unlock(&ipmi_read_lock);
+ }
+ }
+
+ /* On some machines, the heartbeat will give
+ an error and not work unless we re-enable
+ the timer. So do so. */
+ pretimeout_since_last_heartbeat = 1;
+}
+
+static struct ipmi_user_hndl ipmi_hndlrs =
+{
+ .ipmi_recv_hndl = ipmi_wdog_msg_handler,
+ .ipmi_watchdog_pretimeout = ipmi_wdog_pretimeout_handler
+};
+
+static void ipmi_register_watchdog(int ipmi_intf)
+{
+ int rv = -EBUSY;
+
+ down_write(&register_sem);
+ if (watchdog_user)
+ goto out;
+
+ rv = ipmi_create_user(ipmi_intf, &ipmi_hndlrs, NULL, &watchdog_user);
+ if (rv < 0) {
+ printk(KERN_CRIT PFX "Unable to register with ipmi\n");
+ goto out;
+ }
+
+ ipmi_get_version(watchdog_user,
+ &ipmi_version_major,
+ &ipmi_version_minor);
+
+ rv = misc_register(&ipmi_wdog_miscdev);
+ if (rv < 0) {
+ ipmi_destroy_user(watchdog_user);
+ watchdog_user = NULL;
+ printk(KERN_CRIT PFX "Unable to register misc device\n");
+ }
+
+ out:
+ up_write(&register_sem);
+
+ if ((start_now) && (rv == 0)) {
+ /* Run from startup, so start the timer now. */
+ start_now = 0; /* Disable this function after first startup. */
+ ipmi_watchdog_state = action_val;
+ ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB);
+ printk(KERN_INFO PFX "Starting now!\n");
+ }
+}
+
+#ifdef HAVE_NMI_HANDLER
+static int
+ipmi_nmi(void *dev_id, struct pt_regs *regs, int cpu, int handled)
+{
+ /* If no one else handled the NMI, we assume it was the IPMI
+ watchdog. */
+ if ((!handled) && (preop_val == WDOG_PREOP_PANIC))
+ panic(PFX "pre-timeout");
+
+ /* On some machines, the heartbeat will give
+ an error and not work unless we re-enable
+ the timer. So do so. */
+ pretimeout_since_last_heartbeat = 1;
+
+ return NOTIFY_DONE;
+}
+
+static struct nmi_handler ipmi_nmi_handler =
+{
+ .link = LIST_HEAD_INIT(ipmi_nmi_handler.link),
+ .dev_name = "ipmi_watchdog",
+ .dev_id = NULL,
+ .handler = ipmi_nmi,
+ .priority = 0, /* Call us last. */
+};
+#endif
+
+static int wdog_reboot_handler(struct notifier_block *this,
+ unsigned long code,
+ void *unused)
+{
+ static int reboot_event_handled = 0;
+
+ if ((watchdog_user) && (!reboot_event_handled)) {
+ /* Make sure we only do this once. */
+ reboot_event_handled = 1;
+
+ if (code == SYS_DOWN || code == SYS_HALT) {
+ /* Disable the WDT if we are shutting down. */
+ ipmi_watchdog_state = WDOG_TIMEOUT_NONE;
+ panic_halt_ipmi_set_timeout();
+ } else {
+ /* Set a long timer to let the reboot happens, but
+ reboot if it hangs. */
+ timeout = 120;
+ pretimeout = 0;
+ ipmi_watchdog_state = WDOG_TIMEOUT_RESET;
+ panic_halt_ipmi_set_timeout();
+ }
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block wdog_reboot_notifier = {
+ .notifier_call = wdog_reboot_handler,
+ .next = NULL,
+ .priority = 0
+};
+
+static int wdog_panic_handler(struct notifier_block *this,
+ unsigned long event,
+ void *unused)
+{
+ static int panic_event_handled = 0;
+
+ /* On a panic, if we have a panic timeout, make sure that the thing
+ reboots, even if it hangs during that panic. */
+ if (watchdog_user && !panic_event_handled) {
+ /* Make sure the panic doesn't hang, and make sure we
+ do this only once. */
+ panic_event_handled = 1;
+
+ timeout = 255;
+ pretimeout = 0;
+ ipmi_watchdog_state = WDOG_TIMEOUT_RESET;
+ panic_halt_ipmi_set_timeout();
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block wdog_panic_notifier = {
+ .notifier_call = wdog_panic_handler,
+ .next = NULL,
+ .priority = 150 /* priority: INT_MAX >= x >= 0 */
+};
+
+
+static void ipmi_new_smi(int if_num)
+{
+ ipmi_register_watchdog(if_num);
+}
+
+static void ipmi_smi_gone(int if_num)
+{
+ /* This can never be called, because once the watchdog is
+ registered, the interface can't go away until the watchdog
+ is unregistered. */
+}
+
+static struct ipmi_smi_watcher smi_watcher =
+{
+ .owner = THIS_MODULE,
+ .new_smi = ipmi_new_smi,
+ .smi_gone = ipmi_smi_gone
+};
+
+static int __init ipmi_wdog_init(void)
+{
+ int rv;
+
+ printk(KERN_INFO PFX "driver version "
+ IPMI_WATCHDOG_VERSION "\n");
+
+ if (strcmp(action, "reset") == 0) {
+ action_val = WDOG_TIMEOUT_RESET;
+ } else if (strcmp(action, "none") == 0) {
+ action_val = WDOG_TIMEOUT_NONE;
+ } else if (strcmp(action, "power_cycle") == 0) {
+ action_val = WDOG_TIMEOUT_POWER_CYCLE;
+ } else if (strcmp(action, "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);
+ }
+
+ if (strcmp(preaction, "pre_none") == 0) {
+ preaction_val = WDOG_PRETIMEOUT_NONE;
+ } else if (strcmp(preaction, "pre_smi") == 0) {
+ preaction_val = WDOG_PRETIMEOUT_SMI;
+#ifdef HAVE_NMI_HANDLER
+ } else if (strcmp(preaction, "pre_nmi") == 0) {
+ preaction_val = WDOG_PRETIMEOUT_NMI;
+#endif
+ } else if (strcmp(preaction, "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);
+ }
+
+ if (strcmp(preop, "preop_none") == 0) {
+ preop_val = WDOG_PREOP_NONE;
+ } else if (strcmp(preop, "preop_panic") == 0) {
+ preop_val = WDOG_PREOP_PANIC;
+ } else if (strcmp(preop, "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);
+ }
+
+#ifdef HAVE_NMI_HANDLER
+ if (preaction_val == WDOG_PRETIMEOUT_NMI) {
+ 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;
+ }
+#ifdef CONFIG_X86_LOCAL_APIC
+ if (nmi_watchdog == NMI_IO_APIC) {
+ printk(KERN_WARNING PFX "nmi_watchdog is set to IO APIC"
+ " mode (value is %d), that is incompatible"
+ " with using NMI in the IPMI watchdog."
+ " Disabling IPMI nmi pretimeout.\n",
+ nmi_watchdog);
+ preaction_val = WDOG_PRETIMEOUT_NONE;
+ } else {
+#endif
+ 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
+ }
+#endif
+
+ rv = ipmi_smi_watcher_register(&smi_watcher);
+ if (rv) {
+#ifdef HAVE_NMI_HANDLER
+ if (preaction_val == WDOG_PRETIMEOUT_NMI)
+ release_nmi(&ipmi_nmi_handler);
+#endif
+ printk(KERN_WARNING PFX "can't register smi watcher\n");
+ return rv;
+ }
+
+ register_reboot_notifier(&wdog_reboot_notifier);
+ notifier_chain_register(&panic_notifier_list, &wdog_panic_notifier);
+
+ return 0;
+}
+
+static __exit void ipmi_unregister_watchdog(void)
+{
+ int rv;
+
+ down_write(&register_sem);
+
+#ifdef HAVE_NMI_HANDLER
+ if (preaction_val == WDOG_PRETIMEOUT_NMI)
+ release_nmi(&ipmi_nmi_handler);
+#endif
+
+ notifier_chain_unregister(&panic_notifier_list, &wdog_panic_notifier);
+ unregister_reboot_notifier(&wdog_reboot_notifier);
+
+ if (! watchdog_user)
+ goto out;
+
+ /* Make sure no one can call us any more. */
+ misc_deregister(&ipmi_wdog_miscdev);
+
+ /* Wait to make sure the message makes it out. The lower layer has
+ pointers to our buffers, we want to make sure they are done before
+ we release our memory. */
+ while (atomic_read(&set_timeout_tofree)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+
+ /* Disconnect from IPMI. */
+ rv = ipmi_destroy_user(watchdog_user);
+ if (rv) {
+ printk(KERN_WARNING PFX "error unlinking from IPMI: %d\n",
+ rv);
+ }
+ watchdog_user = NULL;
+
+ out:
+ up_write(&register_sem);
+}
+
+static void __exit ipmi_wdog_exit(void)
+{
+ ipmi_smi_watcher_unregister(&smi_watcher);
+ ipmi_unregister_watchdog();
+}
+module_exit(ipmi_wdog_exit);
+module_init(ipmi_wdog_init);
+MODULE_LICENSE("GPL");
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