Initial import

1 files changed, 212 insertions, 0 deletions

diff --git a/drivers/s390/char/sclp_async.c b/drivers/s390/char/sclp_async.c
new file mode 100644
index 000000000..19c25427f
--- /dev/null
+++ b/drivers/s390/char/sclp_async.c
@@ -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");