Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 292 insertions, 0 deletions

diff --git a/drivers/s390/char/vmwatchdog.c b/drivers/s390/char/vmwatchdog.c
new file mode 100644
index 00000000000..22cf4fec8da
--- /dev/null
+++ b/drivers/s390/char/vmwatchdog.c
@@ -0,0 +1,292 @@
+/*
+ * Watchdog implementation based on z/VM Watchdog Timer API
+ *
+ * The user space watchdog daemon can use this driver as
+ * /dev/vmwatchdog to have z/VM execute the specified CP
+ * command when the timeout expires. The default command is
+ * "IPL", which which cause an immediate reboot.
+ */
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/watchdog.h>
+
+#include <asm/ebcdic.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+#define MAX_CMDLEN 240
+#define MIN_INTERVAL 15
+static char vmwdt_cmd[MAX_CMDLEN] = "IPL";
+static int vmwdt_conceal;
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+static int vmwdt_nowayout = 1;
+#else
+static int vmwdt_nowayout = 0;
+#endif
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
+MODULE_DESCRIPTION("z/VM Watchdog Timer");
+module_param_string(cmd, vmwdt_cmd, MAX_CMDLEN, 0644);
+MODULE_PARM_DESC(cmd, "CP command that is run when the watchdog triggers");
+module_param_named(conceal, vmwdt_conceal, bool, 0644);
+MODULE_PARM_DESC(conceal, "Enable the CONCEAL CP option while the watchdog "
+                " is active");
+module_param_named(nowayout, vmwdt_nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"
+                " (default=CONFIG_WATCHDOG_NOWAYOUT)");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
+
+static unsigned int vmwdt_interval = 60;
+static unsigned long vmwdt_is_open;
+static int vmwdt_expect_close;
+
+enum vmwdt_func {
+        /* function codes */
+        wdt_init   = 0,
+        wdt_change = 1,
+        wdt_cancel = 2,
+        /* flags */
+        wdt_conceal = 0x80000000,
+};
+
+static int __diag288(enum vmwdt_func func, unsigned int timeout,
+                            char *cmd, size_t len)
+{
+        register unsigned long __func asm("2");
+        register unsigned long __timeout asm("3");
+        register unsigned long __cmdp asm("4");
+        register unsigned long __cmdl asm("5");
+        int err;
+
+        __func = func;
+        __timeout = timeout;
+        __cmdp = virt_to_phys(cmd);
+        __cmdl = len;
+        err = 0;
+        asm volatile (
+#ifdef __s390x__
+                       "diag %2,%4,0x288\n"
+                "1:     \n"
+                ".section .fixup,\"ax\"\n"
+                "2:     lghi %0,%1\n"
+                "       jg 1b\n"
+                ".previous\n"
+                ".section __ex_table,\"a\"\n"
+                "       .align 8\n"
+                "       .quad 1b,2b\n"
+                ".previous\n"
+#else
+                       "diag %2,%4,0x288\n"
+                "1:     \n"
+                ".section .fixup,\"ax\"\n"
+                "2:     lhi %0,%1\n"
+                "       bras 1,3f\n"
+                "       .long 1b\n"
+                "3:     l 1,0(1)\n"
+                "       br 1\n"
+                ".previous\n"
+                ".section __ex_table,\"a\"\n"
+                "       .align 4\n"
+                "       .long 1b,2b\n"
+                ".previous\n"
+#endif
+                : "+&d"(err)
+                : "i"(-EINVAL), "d"(__func), "d"(__timeout),
+                  "d"(__cmdp), "d"(__cmdl)
+                : "1", "cc");
+        return err;
+}
+
+static int vmwdt_keepalive(void)
+{
+        /* we allocate new memory every time to avoid having
+         * to track the state. static allocation is not an
+         * option since that might not be contiguous in real
+         * storage in case of a modular build */
+        static char *ebc_cmd;
+        size_t len;
+        int ret;
+        unsigned int func;
+
+        ebc_cmd = kmalloc(MAX_CMDLEN, GFP_KERNEL);
+        if (!ebc_cmd)
+                return -ENOMEM;
+
+        len = strlcpy(ebc_cmd, vmwdt_cmd, MAX_CMDLEN);
+        ASCEBC(ebc_cmd, MAX_CMDLEN);
+        EBC_TOUPPER(ebc_cmd, MAX_CMDLEN);
+
+        func = vmwdt_conceal ? (wdt_init | wdt_conceal) : wdt_init;
+        ret = __diag288(func, vmwdt_interval, ebc_cmd, len);
+        kfree(ebc_cmd);
+
+        if (ret) {
+                printk(KERN_WARNING "%s: problem setting interval %d, "
+                        "cmd %s\n", __FUNCTION__, vmwdt_interval,
+                        vmwdt_cmd);
+        }
+        return ret;
+}
+
+static int vmwdt_disable(void)
+{
+        int ret = __diag288(wdt_cancel, 0, "", 0);
+        if (ret) {
+                printk(KERN_WARNING "%s: problem disabling watchdog\n",
+                        __FUNCTION__);
+        }
+        return ret;
+}
+
+static int __init vmwdt_probe(void)
+{
+        /* there is no real way to see if the watchdog is supported,
+         * so we try initializing it with a NOP command ("BEGIN")
+         * that won't cause any harm even if the following disable
+         * fails for some reason */
+        static char __initdata ebc_begin[] = {
+                194, 197, 199, 201, 213
+        };
+        if (__diag288(wdt_init, 15, ebc_begin, sizeof(ebc_begin)) != 0) {
+                printk(KERN_INFO "z/VM watchdog not available\n");
+                return -EINVAL;
+        }
+        return vmwdt_disable();
+}
+
+static int vmwdt_open(struct inode *i, struct file *f)
+{
+        int ret;
+        if (test_and_set_bit(0, &vmwdt_is_open))
+                return -EBUSY;
+        ret = vmwdt_keepalive();
+        if (ret)
+                clear_bit(0, &vmwdt_is_open);
+        return ret ? ret : nonseekable_open(i, f);
+}
+
+static int vmwdt_close(struct inode *i, struct file *f)
+{
+        if (vmwdt_expect_close == 42)
+                vmwdt_disable();
+        vmwdt_expect_close = 0;
+        clear_bit(0, &vmwdt_is_open);
+        return 0;
+}
+
+static struct watchdog_info vmwdt_info = {
+        .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+        .firmware_version = 0,
+        .identity = "z/VM Watchdog Timer",
+};
+
+static int vmwdt_ioctl(struct inode *i, struct file *f,
+                          unsigned int cmd, unsigned long arg)
+{
+        switch (cmd) {
+        case WDIOC_GETSUPPORT:
+                if (copy_to_user((void __user *)arg, &vmwdt_info,
+                                        sizeof(vmwdt_info)))
+                        return -EFAULT;
+                return 0;
+        case WDIOC_GETSTATUS:
+        case WDIOC_GETBOOTSTATUS:
+                return put_user(0, (int *)arg);
+        case WDIOC_GETTEMP:
+                return -EINVAL;
+        case WDIOC_SETOPTIONS:
+                {
+                        int options, ret;
+                        if (get_user(options, (int __user *)arg))
+                                return -EFAULT;
+                        ret = -EINVAL;
+                        if (options & WDIOS_DISABLECARD) {
+                                ret = vmwdt_disable();
+                                if (ret)
+                                        return ret;
+                        }
+                        if (options & WDIOS_ENABLECARD) {
+                                ret = vmwdt_keepalive();
+                        }
+                        return ret;
+                }
+        case WDIOC_GETTIMEOUT:
+                return put_user(vmwdt_interval, (int __user *)arg);
+        case WDIOC_SETTIMEOUT:
+                {
+                        int interval;
+                        if (get_user(interval, (int __user *)arg))
+                                return -EFAULT;
+                        if (interval < MIN_INTERVAL)
+                                return -EINVAL;
+                        vmwdt_interval = interval;
+                }
+                return vmwdt_keepalive();
+        case WDIOC_KEEPALIVE:
+                return vmwdt_keepalive();
+        }
+
+        return -EINVAL;
+}
+
+static ssize_t vmwdt_write(struct file *f, const char __user *buf,
+                                size_t count, loff_t *ppos)
+{
+        if(count) {
+                if (!vmwdt_nowayout) {
+                        size_t i;
+
+                        /* note: just in case someone wrote the magic character
+                         * five months ago... */
+                        vmwdt_expect_close = 0;
+
+                        for (i = 0; i != count; i++) {
+                                char c;
+                                if (get_user(c, buf+i))
+                                        return -EFAULT;
+                                if (c == 'V')
+                                        vmwdt_expect_close = 42;
+                        }
+                }
+                /* someone wrote to us, we should restart timer */
+                vmwdt_keepalive();
+        }
+        return count;
+}
+
+static struct file_operations vmwdt_fops = {
+        .open    = &vmwdt_open,
+        .release = &vmwdt_close,
+        .ioctl   = &vmwdt_ioctl,
+        .write   = &vmwdt_write,
+        .owner   = THIS_MODULE,
+};
+
+static struct miscdevice vmwdt_dev = {
+        .minor      = WATCHDOG_MINOR,
+        .name       = "watchdog",
+        .fops       = &vmwdt_fops,
+};
+
+static int __init vmwdt_init(void)
+{
+        int ret;
+
+        ret = vmwdt_probe();
+        if (ret)
+                return ret;
+        return misc_register(&vmwdt_dev);
+}
+module_init(vmwdt_init);
+
+static void __exit vmwdt_exit(void)
+{
+        WARN_ON(misc_deregister(&vmwdt_dev) != 0);
+}
+module_exit(vmwdt_exit);