v4.19.13 snapshot.
diff --git a/drivers/s390/char/sclp_async.c b/drivers/s390/char/sclp_async.c
new file mode 100644
index 0000000..e69b12a
--- /dev/null
+++ b/drivers/s390/char/sclp_async.c
@@ -0,0 +1,189 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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 zero;
+static int one = 1;
+
+static struct ctl_table callhome_table[] = {
+ {
+ .procname = "callhome",
+ .data = &callhome_enabled,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
+ {}
+};
+
+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");