[S390] iucv: establish reboot notifier

To guarantee a proper cleanup, patch adds a reboot notifier to
the iucv base code, which disables iucv interrupts, shuts down
established iucv pathes, and removes iucv declarations for z/VM.

Checks have to be added to the iucv-API functions, whether
iucv-buffers removed at reboot time are still declared.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 87 insertions, 2 deletions

diff --git a/net/iucv/iucv.c b/net/iucv/iucv.c
index 61e8038a55ee..0e9f212dd928 100644
--- a/net/iucv/iucv.c
+++ b/net/iucv/iucv.c
@@ -1,7 +1,8 @@
 /*
  * IUCV base infrastructure.
  *
- * Copyright 2001, 2006 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Copyright IBM Corp. 2001, 2009
+ *
  * Author(s):
  *    Original source:
  *      Alan Altmark (Alan_Altmark@us.ibm.com)  Sept. 2000
@@ -45,6 +46,7 @@
 #include <linux/err.h>
 #include <linux/device.h>
 #include <linux/cpu.h>
+#include <linux/reboot.h>
 #include <net/iucv/iucv.h>
 #include <asm/atomic.h>
 #include <asm/ebcdic.h>
@@ -758,6 +760,28 @@ void iucv_unregister(struct iucv_handler *handler, int smp)
 }
 EXPORT_SYMBOL(iucv_unregister);
 
+static int iucv_reboot_event(struct notifier_block *this,
+                             unsigned long event, void *ptr)
+{
+        int i, rc;
+
+        get_online_cpus();
+        on_each_cpu(iucv_block_cpu, NULL, 1);
+        preempt_disable();
+        for (i = 0; i < iucv_max_pathid; i++) {
+                if (iucv_path_table[i])
+                        rc = iucv_sever_pathid(i, NULL);
+        }
+        preempt_enable();
+        put_online_cpus();
+        iucv_disable();
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block iucv_reboot_notifier = {
+        .notifier_call = iucv_reboot_event,
+};
+
 /**
  * iucv_path_accept
  * @path: address of iucv path structure
@@ -777,6 +801,10 @@ int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
         int rc;
 
         local_bh_disable();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         /* Prepare parameter block. */
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
@@ -792,6 +820,7 @@ int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
                 path->msglim = parm->ctrl.ipmsglim;
                 path->flags = parm->ctrl.ipflags1;
         }
+out:
         local_bh_enable();
         return rc;
 }
@@ -821,6 +850,10 @@ int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
 
         spin_lock_bh(&iucv_table_lock);
         iucv_cleanup_queue();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         parm->ctrl.ipmsglim = path->msglim;
@@ -855,6 +888,7 @@ int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
                         rc = -EIO;
                 }
         }
+out:
         spin_unlock_bh(&iucv_table_lock);
         return rc;
 }
@@ -876,12 +910,17 @@ int iucv_path_quiesce(struct iucv_path *path, u8 userdata[16])
         int rc;
 
         local_bh_disable();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         if (userdata)
                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
         parm->ctrl.ippathid = path->pathid;
         rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
+out:
         local_bh_enable();
         return rc;
 }
@@ -903,12 +942,17 @@ int iucv_path_resume(struct iucv_path *path, u8 userdata[16])
         int rc;
 
         local_bh_disable();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         if (userdata)
                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
         parm->ctrl.ippathid = path->pathid;
         rc = iucv_call_b2f0(IUCV_RESUME, parm);
+out:
         local_bh_enable();
         return rc;
 }
@@ -927,6 +971,10 @@ int iucv_path_sever(struct iucv_path *path, u8 userdata[16])
         int rc;
 
         preempt_disable();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         if (iucv_active_cpu != smp_processor_id())
                 spin_lock_bh(&iucv_table_lock);
         rc = iucv_sever_pathid(path->pathid, userdata);
@@ -934,6 +982,7 @@ int iucv_path_sever(struct iucv_path *path, u8 userdata[16])
         list_del_init(&path->list);
         if (iucv_active_cpu != smp_processor_id())
                 spin_unlock_bh(&iucv_table_lock);
+out:
         preempt_enable();
         return rc;
 }
@@ -956,6 +1005,10 @@ int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
         int rc;
 
         local_bh_disable();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         parm->purge.ippathid = path->pathid;
@@ -967,6 +1020,7 @@ int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
                 msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
                 msg->tag = parm->purge.ipmsgtag;
         }
+out:
         local_bh_enable();
         return rc;
 }
@@ -1043,6 +1097,10 @@ int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
         if (msg->flags & IUCV_IPRMDATA)
                 return iucv_message_receive_iprmdata(path, msg, flags,
                                                      buffer, size, residual);
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         parm->db.ipbfadr1 = (u32)(addr_t) buffer;
@@ -1058,6 +1116,7 @@ int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
                 if (residual)
                         *residual = parm->db.ipbfln1f;
         }
+out:
         return rc;
 }
 EXPORT_SYMBOL(__iucv_message_receive);
@@ -1111,6 +1170,10 @@ int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
         int rc;
 
         local_bh_disable();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         parm->db.ippathid = path->pathid;
@@ -1118,6 +1181,7 @@ int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
         parm->db.iptrgcls = msg->class;
         parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
         rc = iucv_call_b2f0(IUCV_REJECT, parm);
+out:
         local_bh_enable();
         return rc;
 }
@@ -1145,6 +1209,10 @@ int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
         int rc;
 
         local_bh_disable();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         if (flags & IUCV_IPRMDATA) {
@@ -1162,6 +1230,7 @@ int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
                 parm->db.iptrgcls = msg->class;
         }
         rc = iucv_call_b2f0(IUCV_REPLY, parm);
+out:
         local_bh_enable();
         return rc;
 }
@@ -1190,6 +1259,10 @@ int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
         union iucv_param *parm;
         int rc;
 
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         if (flags & IUCV_IPRMDATA) {
@@ -1212,6 +1285,7 @@ int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
         rc = iucv_call_b2f0(IUCV_SEND, parm);
         if (!rc)
                 msg->id = parm->db.ipmsgid;
+out:
         return rc;
 }
 EXPORT_SYMBOL(__iucv_message_send);
@@ -1272,6 +1346,10 @@ int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
         int rc;
 
         local_bh_disable();
+        if (!cpu_isset(smp_processor_id(), iucv_buffer_cpumask)) {
+                rc = -EIO;
+                goto out;
+        }
         parm = iucv_param[smp_processor_id()];
         memset(parm, 0, sizeof(union iucv_param));
         if (flags & IUCV_IPRMDATA) {
@@ -1297,6 +1375,7 @@ int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
         rc = iucv_call_b2f0(IUCV_SEND, parm);
         if (!rc)
                 msg->id = parm->db.ipmsgid;
+out:
         local_bh_enable();
         return rc;
 }
@@ -1740,15 +1819,20 @@ static int __init iucv_init(void)
         rc = register_hotcpu_notifier(&iucv_cpu_notifier);
         if (rc)
                 goto out_free;
+        rc = register_reboot_notifier(&iucv_reboot_notifier);
+        if (rc)
+                goto out_cpu;
         ASCEBC(iucv_error_no_listener, 16);
         ASCEBC(iucv_error_no_memory, 16);
         ASCEBC(iucv_error_pathid, 16);
         iucv_available = 1;
         rc = bus_register(&iucv_bus);
         if (rc)
-                goto out_cpu;
+                goto out_reboot;
         return 0;
 
+out_reboot:
+        unregister_reboot_notifier(&iucv_reboot_notifier);
 out_cpu:
         unregister_hotcpu_notifier(&iucv_cpu_notifier);
 out_free:
@@ -1783,6 +1867,7 @@ static void __exit iucv_exit(void)
         list_for_each_entry_safe(p, n, &iucv_work_queue, list)
                 kfree(p);
         spin_unlock_irq(&iucv_queue_lock);
+        unregister_reboot_notifier(&iucv_reboot_notifier);
         unregister_hotcpu_notifier(&iucv_cpu_notifier);
         for_each_possible_cpu(cpu) {
                 kfree(iucv_param_irq[cpu]);