[S390] add call home support

Signed-off-by: Hans-Joachim Picht <hans@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

4 files changed, 238 insertions, 1 deletions

diff --git a/drivers/s390/char/Kconfig b/drivers/s390/char/Kconfig
index 0769ced52dbd..4e34d3686c23 100644
--- a/drivers/s390/char/Kconfig
+++ b/drivers/s390/char/Kconfig
@@ -82,6 +82,16 @@ config SCLP_CPI
           You should only select this option if you know what you are doing,
           need this feature and intend to run your kernel in LPAR.
 
+config SCLP_ASYNC
+        tristate "Support for Call Home via Asynchronous SCLP Records"
+        depends on S390
+        help
+          This option enables the call home function, which is able to inform
+          the service element and connected organisations about a kernel panic.
+          You should only select this option if you know what you are doing,
+          want for inform other people about your kernel panics,
+          need this feature and intend to run your kernel in LPAR.
+
 config S390_TAPE
         tristate "S/390 tape device support"
         depends on CCW
diff --git a/drivers/s390/char/Makefile b/drivers/s390/char/Makefile
index 7e73e39a1741..efb500ab66c0 100644
--- a/drivers/s390/char/Makefile
+++ b/drivers/s390/char/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_SCLP_TTY) += sclp_tty.o
 obj-$(CONFIG_SCLP_CONSOLE) += sclp_con.o
 obj-$(CONFIG_SCLP_VT220_TTY) += sclp_vt220.o
 obj-$(CONFIG_SCLP_CPI) += sclp_cpi.o
+obj-$(CONFIG_SCLP_ASYNC) += sclp_async.o
 
 obj-$(CONFIG_ZVM_WATCHDOG) += vmwatchdog.o
 obj-$(CONFIG_VMLOGRDR) += vmlogrdr.o
diff --git a/drivers/s390/char/sclp.h b/drivers/s390/char/sclp.h
index 60e7cb07095b..6bb5a6bdfab5 100644
--- a/drivers/s390/char/sclp.h
+++ b/drivers/s390/char/sclp.h
@@ -27,6 +27,7 @@
 #define EVTYP_VT220MSG          0x1A
 #define EVTYP_CONFMGMDATA       0x04
 #define EVTYP_SDIAS             0x1C
+#define EVTYP_ASYNC             0x0A
 
 #define EVTYP_OPCMD_MASK        0x80000000
 #define EVTYP_MSG_MASK          0x40000000
@@ -38,6 +39,7 @@
 #define EVTYP_VT220MSG_MASK     0x00000040
 #define EVTYP_CONFMGMDATA_MASK  0x10000000
 #define EVTYP_SDIAS_MASK        0x00000010
+#define EVTYP_ASYNC_MASK        0x00400000
 
 #define GNRLMSGFLGS_DOM         0x8000
 #define GNRLMSGFLGS_SNDALRM     0x4000
@@ -85,12 +87,12 @@ struct sccb_header {
 } __attribute__((packed));
 
 extern u64 sclp_facilities;
-
 #define SCLP_HAS_CHP_INFO       (sclp_facilities & 0x8000000000000000ULL)
 #define SCLP_HAS_CHP_RECONFIG   (sclp_facilities & 0x2000000000000000ULL)
 #define SCLP_HAS_CPU_INFO       (sclp_facilities & 0x0800000000000000ULL)
 #define SCLP_HAS_CPU_RECONFIG   (sclp_facilities & 0x0400000000000000ULL)
 
+
 struct gds_subvector {
         u8      length;
         u8      key;
diff --git a/drivers/s390/char/sclp_async.c b/drivers/s390/char/sclp_async.c
new file mode 100644
index 000000000000..daaec185ed36
--- /dev/null
+++ b/drivers/s390/char/sclp_async.c
@@ -0,0 +1,224 @@
+/*
+ * Enable Asynchronous Notification via SCLP.
+ *
+ * Copyright IBM Corp. 2009
+ * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/kmod.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/proc_fs.h>
+#include <linux/sysctl.h>
+#include <linux/utsname.h>
+#include "sclp.h"
+
+static int callhome_enabled;
+static struct sclp_req *request;
+static struct sclp_async_sccb *sccb;
+static int sclp_async_send_wait(char *message);
+static struct ctl_table_header *callhome_sysctl_header;
+static DEFINE_SPINLOCK(sclp_async_lock);
+static char nodename[64];
+#define SCLP_NORMAL_WRITE       0x00
+
+struct async_evbuf {
+        struct evbuf_header header;
+        u64 reserved;
+        u8 rflags;
+        u8 empty;
+        u8 rtype;
+        u8 otype;
+        char comp_id[12];
+        char data[3000]; /* there is still some space left */
+} __attribute__((packed));
+
+struct sclp_async_sccb {
+        struct sccb_header header;
+        struct async_evbuf evbuf;
+} __attribute__((packed));
+
+static struct sclp_register sclp_async_register = {
+        .send_mask = EVTYP_ASYNC_MASK,
+};
+
+static int call_home_on_panic(struct notifier_block *self,
+                              unsigned long event, void *data)
+{
+                strncat(data, nodename, strlen(nodename));
+                sclp_async_send_wait(data);
+                return NOTIFY_DONE;
+}
+
+static struct notifier_block call_home_panic_nb = {
+        .notifier_call = call_home_on_panic,
+        .priority = INT_MAX,
+};
+
+static int proc_handler_callhome(ctl_table *ctl, int write, struct file *filp,
+                                 void __user *buffer, size_t *count,
+                                 loff_t *ppos)
+{
+        unsigned long val;
+        int len, rc;
+        char buf[2];
+
+        if (!*count | (*ppos && !write)) {
+                *count = 0;
+                return 0;
+        }
+        if (!write) {
+                len =  sprintf(buf, "%d\n", callhome_enabled);
+                buf[len] = '\0';
+                rc = copy_to_user(buffer, buf, sizeof(buf));
+                if (rc != 0)
+                        return -EFAULT;
+        } else {
+                len = *count;
+                rc = copy_from_user(buf, buffer, sizeof(buf));
+                if (rc != 0)
+                        return -EFAULT;
+                if (strict_strtoul(buf, 0, &val) != 0)
+                        return -EINVAL;
+                if (val != 0 && val != 1)
+                        return -EINVAL;
+                callhome_enabled = val;
+        }
+        *count = len;
+        *ppos += len;
+        return 0;
+}
+
+static struct ctl_table callhome_table[] = {
+        {
+                .procname       = "callhome",
+                .mode           = 0644,
+                .proc_handler   = &proc_handler_callhome,
+        },
+        { .ctl_name = 0 }
+};
+
+static struct ctl_table kern_dir_table[] = {
+        {
+                .ctl_name       = CTL_KERN,
+                .procname       = "kernel",
+                .maxlen         = 0,
+                .mode           = 0555,
+                .child          = callhome_table,
+        },
+        { .ctl_name = 0 }
+};
+
+/*
+ * Function used to transfer asynchronous notification
+ * records which waits for send completion
+ */
+static int sclp_async_send_wait(char *message)
+{
+        struct async_evbuf *evb;
+        int rc;
+        unsigned long flags;
+
+        if (!callhome_enabled)
+                return 0;
+        sccb->evbuf.header.type = EVTYP_ASYNC;
+        sccb->evbuf.rtype = 0xA5;
+        sccb->evbuf.otype = 0x00;
+        evb = &sccb->evbuf;
+        request->command = SCLP_CMDW_WRITE_EVENT_DATA;
+        request->sccb = sccb;
+        request->status = SCLP_REQ_FILLED;
+        strncpy(sccb->evbuf.data, message, sizeof(sccb->evbuf.data));
+        /*
+         * Retain Queue
+         * e.g. 5639CC140 500 Red Hat RHEL5 Linux for zSeries (RHEL AS)
+         */
+        strncpy(sccb->evbuf.comp_id, "000000000", sizeof(sccb->evbuf.comp_id));
+        sccb->evbuf.header.length = sizeof(sccb->evbuf);
+        sccb->header.length = sizeof(sccb->evbuf) + sizeof(sccb->header);
+        sccb->header.function_code = SCLP_NORMAL_WRITE;
+        rc = sclp_add_request(request);
+        if (rc)
+                return rc;
+        spin_lock_irqsave(&sclp_async_lock, flags);
+        while (request->status != SCLP_REQ_DONE &&
+                request->status != SCLP_REQ_FAILED) {
+                 sclp_sync_wait();
+        }
+        spin_unlock_irqrestore(&sclp_async_lock, flags);
+        if (request->status != SCLP_REQ_DONE)
+                return -EIO;
+        rc = ((struct sclp_async_sccb *)
+               request->sccb)->header.response_code;
+        if (rc != 0x0020)
+                return -EIO;
+        if (evb->header.flags != 0x80)
+                return -EIO;
+        return rc;
+}
+
+static int __init sclp_async_init(void)
+{
+        int rc;
+
+        rc = sclp_register(&sclp_async_register);
+        if (rc)
+                return rc;
+        callhome_sysctl_header = register_sysctl_table(kern_dir_table);
+        if (!callhome_sysctl_header) {
+                rc = -ENOMEM;
+                goto out_sclp;
+        }
+        if (!(sclp_async_register.sclp_receive_mask & EVTYP_ASYNC_MASK)) {
+                rc = -EOPNOTSUPP;
+                goto out_sclp;
+        }
+        rc = -ENOMEM;
+        request = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
+        if (!request)
+                goto out_sys;
+        sccb = (struct sclp_async_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+        if (!sccb)
+                goto out_mem;
+        rc =  atomic_notifier_chain_register(&panic_notifier_list,
+                                             &call_home_panic_nb);
+        if (rc)
+                goto out_mem;
+
+        strncpy(nodename, init_utsname()->nodename, 64);
+        return 0;
+
+out_mem:
+        kfree(request);
+        free_page((unsigned long) sccb);
+out_sys:
+        unregister_sysctl_table(callhome_sysctl_header);
+out_sclp:
+        sclp_unregister(&sclp_async_register);
+        return rc;
+
+}
+module_init(sclp_async_init);
+
+static void __exit sclp_async_exit(void)
+{
+        atomic_notifier_chain_unregister(&panic_notifier_list,
+                                         &call_home_panic_nb);
+        unregister_sysctl_table(callhome_sysctl_header);
+        sclp_unregister(&sclp_async_register);
+        free_page((unsigned long) sccb);
+        kfree(request);
+}
+module_exit(sclp_async_exit);
+
+MODULE_AUTHOR("Copyright IBM Corp. 2009");
+MODULE_AUTHOR("Hans-Joachim Picht <hans@linux.vnet.ibm.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SCLP Asynchronous Notification Records");