[S390] Automatic IPL after dump

Provide new shutdown action "dump_reipl" for automatic ipl after dump.

Signed-off-by: Frank Munzert <munzert@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
diff --git a/drivers/s390/char/zcore.c b/drivers/s390/char/zcore.c
index eefc661..cfe782e 100644
--- a/drivers/s390/char/zcore.c
+++ b/drivers/s390/char/zcore.c
@@ -5,7 +5,7 @@
  *
  * For more information please refer to Documentation/s390/zfcpdump.txt
  *
- * Copyright IBM Corp. 2003,2007
+ * Copyright IBM Corp. 2003,2008
  * Author(s): Michael Holzheu
  */
 
@@ -48,12 +48,19 @@
 	union save_area	lc_mask;
 };
 
+struct ipib_info {
+	unsigned long	ipib;
+	u32		checksum;
+}  __attribute__((packed));
+
 static struct sys_info sys_info;
 static struct debug_info *zcore_dbf;
 static int hsa_available;
 static struct dentry *zcore_dir;
 static struct dentry *zcore_file;
 static struct dentry *zcore_memmap_file;
+static struct dentry *zcore_reipl_file;
+static struct ipl_parameter_block *ipl_block;
 
 /*
  * Copy memory from HSA to kernel or user memory (not reentrant):
@@ -527,6 +534,33 @@
 	.release	= zcore_memmap_release,
 };
 
+static ssize_t zcore_reipl_write(struct file *filp, const char __user *buf,
+				 size_t count, loff_t *ppos)
+{
+	if (ipl_block) {
+		diag308(DIAG308_SET, ipl_block);
+		diag308(DIAG308_IPL, NULL);
+	}
+	return count;
+}
+
+static int zcore_reipl_open(struct inode *inode, struct file *filp)
+{
+	return 0;
+}
+
+static int zcore_reipl_release(struct inode *inode, struct file *filp)
+{
+	return 0;
+}
+
+static const struct file_operations zcore_reipl_fops = {
+	.owner		= THIS_MODULE,
+	.write		= zcore_reipl_write,
+	.open		= zcore_reipl_open,
+	.release	= zcore_reipl_release,
+};
+
 
 static void __init set_s390_lc_mask(union save_area *map)
 {
@@ -645,6 +679,39 @@
 	return 0;
 }
 
+/*
+ * Provide IPL parameter information block from either HSA or memory
+ * for future reipl
+ */
+static int __init zcore_reipl_init(void)
+{
+	struct ipib_info ipib_info;
+	int rc;
+
+	rc = memcpy_hsa_kernel(&ipib_info, __LC_DUMP_REIPL, sizeof(ipib_info));
+	if (rc)
+		return rc;
+	if (ipib_info.ipib == 0)
+		return 0;
+	ipl_block = (void *) __get_free_page(GFP_KERNEL);
+	if (!ipl_block)
+		return -ENOMEM;
+	if (ipib_info.ipib < ZFCPDUMP_HSA_SIZE)
+		rc = memcpy_hsa_kernel(ipl_block, ipib_info.ipib, PAGE_SIZE);
+	else
+		rc = memcpy_real(ipl_block, ipib_info.ipib, PAGE_SIZE);
+	if (rc) {
+		free_page((unsigned long) ipl_block);
+		return rc;
+	}
+	if (cksm(ipl_block, ipl_block->hdr.len) != ipib_info.checksum) {
+		TRACE("Checksum does not match\n");
+		free_page((unsigned long) ipl_block);
+		ipl_block = NULL;
+	}
+	return 0;
+}
+
 static int __init zcore_init(void)
 {
 	unsigned char arch;
@@ -690,6 +757,10 @@
 	if (rc)
 		goto fail;
 
+	rc = zcore_reipl_init();
+	if (rc)
+		goto fail;
+
 	zcore_dir = debugfs_create_dir("zcore" , NULL);
 	if (!zcore_dir) {
 		rc = -ENOMEM;
@@ -707,9 +778,17 @@
 		rc = -ENOMEM;
 		goto fail_file;
 	}
+	zcore_reipl_file = debugfs_create_file("reipl", S_IRUSR, zcore_dir,
+						NULL, &zcore_reipl_fops);
+	if (!zcore_reipl_file) {
+		rc = -ENOMEM;
+		goto fail_memmap_file;
+	}
 	hsa_available = 1;
 	return 0;
 
+fail_memmap_file:
+	debugfs_remove(zcore_memmap_file);
 fail_file:
 	debugfs_remove(zcore_file);
 fail_dir:
@@ -723,10 +802,15 @@
 {
 	debug_unregister(zcore_dbf);
 	sclp_sdias_exit();
+	free_page((unsigned long) ipl_block);
+	debugfs_remove(zcore_reipl_file);
+	debugfs_remove(zcore_memmap_file);
+	debugfs_remove(zcore_file);
+	debugfs_remove(zcore_dir);
 	diag308(DIAG308_REL_HSA, NULL);
 }
 
-MODULE_AUTHOR("Copyright IBM Corp. 2003,2007");
+MODULE_AUTHOR("Copyright IBM Corp. 2003,2008");
 MODULE_DESCRIPTION("zcore module for zfcpdump support");
 MODULE_LICENSE("GPL");