1 // SPDX-License-Identifier: GPL-2.0
3 * Enable Asynchronous Notification via SCLP.
5 * Copyright IBM Corp. 2009
6 * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com>
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/stat.h>
14 #include <linux/string.h>
15 #include <linux/slab.h>
16 #include <linux/ctype.h>
17 #include <linux/kmod.h>
18 #include <linux/err.h>
19 #include <linux/errno.h>
20 #include <linux/proc_fs.h>
21 #include <linux/sysctl.h>
22 #include <linux/utsname.h>
25 static int callhome_enabled;
26 static struct sclp_req *request;
27 static struct sclp_async_sccb *sccb;
28 static int sclp_async_send_wait(char *message);
29 static struct ctl_table_header *callhome_sysctl_header;
30 static DEFINE_SPINLOCK(sclp_async_lock);
31 #define SCLP_NORMAL_WRITE 0x00
34 struct evbuf_header header;
41 char data[3000]; /* there is still some space left */
42 } __attribute__((packed));
44 struct sclp_async_sccb {
45 struct sccb_header header;
46 struct async_evbuf evbuf;
47 } __attribute__((packed));
49 static struct sclp_register sclp_async_register = {
50 .send_mask = EVTYP_ASYNC_MASK,
53 static int call_home_on_panic(struct notifier_block *self,
54 unsigned long event, void *data)
56 strncat(data, init_utsname()->nodename,
57 sizeof(init_utsname()->nodename));
58 sclp_async_send_wait(data);
62 static struct notifier_block call_home_panic_nb = {
63 .notifier_call = call_home_on_panic,
67 static int proc_handler_callhome(struct ctl_table *ctl, int write,
68 void __user *buffer, size_t *count,
75 if (!*count || (*ppos && !write)) {
80 len = snprintf(buf, sizeof(buf), "%d\n", callhome_enabled);
81 rc = copy_to_user(buffer, buf, sizeof(buf));
86 rc = kstrtoul_from_user(buffer, len, 0, &val);
89 if (val != 0 && val != 1)
91 callhome_enabled = val;
98 static struct ctl_table callhome_table[] = {
100 .procname = "callhome",
102 .proc_handler = proc_handler_callhome,
107 static struct ctl_table kern_dir_table[] = {
109 .procname = "kernel",
112 .child = callhome_table,
118 * Function used to transfer asynchronous notification
119 * records which waits for send completion
121 static int sclp_async_send_wait(char *message)
123 struct async_evbuf *evb;
127 if (!callhome_enabled)
129 sccb->evbuf.header.type = EVTYP_ASYNC;
130 sccb->evbuf.rtype = 0xA5;
131 sccb->evbuf.otype = 0x00;
133 request->command = SCLP_CMDW_WRITE_EVENT_DATA;
134 request->sccb = sccb;
135 request->status = SCLP_REQ_FILLED;
136 strncpy(sccb->evbuf.data, message, sizeof(sccb->evbuf.data));
139 * e.g. 5639CC140 500 Red Hat RHEL5 Linux for zSeries (RHEL AS)
141 strncpy(sccb->evbuf.comp_id, CONFIG_SCLP_ASYNC_ID,
142 sizeof(sccb->evbuf.comp_id));
143 sccb->evbuf.header.length = sizeof(sccb->evbuf);
144 sccb->header.length = sizeof(sccb->evbuf) + sizeof(sccb->header);
145 sccb->header.function_code = SCLP_NORMAL_WRITE;
146 rc = sclp_add_request(request);
149 spin_lock_irqsave(&sclp_async_lock, flags);
150 while (request->status != SCLP_REQ_DONE &&
151 request->status != SCLP_REQ_FAILED) {
154 spin_unlock_irqrestore(&sclp_async_lock, flags);
155 if (request->status != SCLP_REQ_DONE)
157 rc = ((struct sclp_async_sccb *)
158 request->sccb)->header.response_code;
161 if (evb->header.flags != 0x80)
166 static int __init sclp_async_init(void)
170 rc = sclp_register(&sclp_async_register);
174 if (!(sclp_async_register.sclp_receive_mask & EVTYP_ASYNC_MASK))
177 callhome_sysctl_header = register_sysctl_table(kern_dir_table);
178 if (!callhome_sysctl_header)
180 request = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
181 sccb = (struct sclp_async_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
182 if (!request || !sccb)
184 rc = atomic_notifier_chain_register(&panic_notifier_list,
185 &call_home_panic_nb);
190 free_page((unsigned long) sccb);
191 unregister_sysctl_table(callhome_sysctl_header);
193 sclp_unregister(&sclp_async_register);
197 module_init(sclp_async_init);
199 static void __exit sclp_async_exit(void)
201 atomic_notifier_chain_unregister(&panic_notifier_list,
202 &call_home_panic_nb);
203 unregister_sysctl_table(callhome_sysctl_header);
204 sclp_unregister(&sclp_async_register);
205 free_page((unsigned long) sccb);
208 module_exit(sclp_async_exit);
210 MODULE_AUTHOR("Copyright IBM Corp. 2009");
211 MODULE_AUTHOR("Hans-Joachim Picht <hans@linux.vnet.ibm.com>");
212 MODULE_LICENSE("GPL");
213 MODULE_DESCRIPTION("SCLP Asynchronous Notification Records");