Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / s390 / char / sclp_async.c
diff --git a/kernel/drivers/s390/char/sclp_async.c b/kernel/drivers/s390/char/sclp_async.c
new file mode 100644 (file)
index 0000000..19c2542
--- /dev/null
@@ -0,0 +1,212 @@
+/*
+ * 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/slab.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);
+#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, init_utsname()->nodename,
+               sizeof(init_utsname()->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(struct ctl_table *ctl, int write,
+                                void __user *buffer, size_t *count,
+                                loff_t *ppos)
+{
+       unsigned long val;
+       int len, rc;
+       char buf[3];
+
+       if (!*count || (*ppos && !write)) {
+               *count = 0;
+               return 0;
+       }
+       if (!write) {
+               len = snprintf(buf, sizeof(buf), "%d\n", callhome_enabled);
+               rc = copy_to_user(buffer, buf, sizeof(buf));
+               if (rc != 0)
+                       return -EFAULT;
+       } else {
+               len = *count;
+               rc = kstrtoul_from_user(buffer, len, 0, &val);
+               if (rc)
+                       return rc;
+               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,
+       },
+       {}
+};
+
+static struct ctl_table kern_dir_table[] = {
+       {
+               .procname       = "kernel",
+               .maxlen         = 0,
+               .mode           = 0555,
+               .child          = callhome_table,
+       },
+       {}
+};
+
+/*
+ * 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, CONFIG_SCLP_ASYNC_ID,
+               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;
+       rc = -EOPNOTSUPP;
+       if (!(sclp_async_register.sclp_receive_mask & EVTYP_ASYNC_MASK))
+               goto out_sclp;
+       rc = -ENOMEM;
+       callhome_sysctl_header = register_sysctl_table(kern_dir_table);
+       if (!callhome_sysctl_header)
+               goto out_sclp;
+       request = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
+       sccb = (struct sclp_async_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+       if (!request || !sccb)
+               goto out_mem;
+       rc = atomic_notifier_chain_register(&panic_notifier_list,
+                                           &call_home_panic_nb);
+       if (!rc)
+               goto out;
+out_mem:
+       kfree(request);
+       free_page((unsigned long) sccb);
+       unregister_sysctl_table(callhome_sysctl_header);
+out_sclp:
+       sclp_unregister(&sclp_async_register);
+out:
+       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");