1 files changed, 42 insertions, 18 deletions

diff --git a/arch/s390/hypfs/hypfs_dbfs.c b/arch/s390/hypfs/hypfs_dbfs.c
index 752f6df3e697..41a0d2066fa0 100644
--- a/arch/s390/hypfs/hypfs_dbfs.c
+++ b/arch/s390/hypfs/hypfs_dbfs.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Hypervisor filesystem for Linux on s390 - debugfs interface
  *
@@ -5,6 +6,7 @@
  * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
  */
 
+#include <linux/security.h>
 #include <linux/slab.h>
 #include "hypfs.h"
 
@@ -38,7 +40,9 @@ static ssize_t dbfs_read(struct file *file, char __user *buf,
 		return 0;
 
 	df = file_inode(file)->i_private;
-	mutex_lock(&df->lock);
+	if (mutex_lock_interruptible(&df->lock))
+		return -ERESTARTSYS;
+
 	data = hypfs_dbfs_data_alloc(df);
 	if (!data) {
 		mutex_unlock(&df->lock);
@@ -63,28 +67,28 @@ static long dbfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	long rc;
 
 	mutex_lock(&df->lock);
-	if (df->unlocked_ioctl)
-		rc = df->unlocked_ioctl(file, cmd, arg);
-	else
-		rc = -ENOTTY;
+	rc = df->unlocked_ioctl(file, cmd, arg);
 	mutex_unlock(&df->lock);
 	return rc;
 }
 
-static const struct file_operations dbfs_ops = {
+static const struct file_operations dbfs_ops_ioctl = {
 	.read		= dbfs_read,
-	.llseek		= no_llseek,
 	.unlocked_ioctl = dbfs_ioctl,
 };
 
-int hypfs_dbfs_create_file(struct hypfs_dbfs_file *df)
+static const struct file_operations dbfs_ops = {
+	.read		= dbfs_read,
+};
+
+void hypfs_dbfs_create_file(struct hypfs_dbfs_file *df)
 {
-	df->dentry = debugfs_create_file(df->name, 0400, dbfs_dir, df,
-					 &dbfs_ops);
-	if (IS_ERR(df->dentry))
-		return PTR_ERR(df->dentry);
+	const struct file_operations *fops = &dbfs_ops;
+
+	if (df->unlocked_ioctl && !security_locked_down(LOCKDOWN_DEBUGFS))
+		fops = &dbfs_ops_ioctl;
+	df->dentry = debugfs_create_file(df->name, 0400, dbfs_dir, df, fops);
 	mutex_init(&df->lock);
-	return 0;
 }
 
 void hypfs_dbfs_remove_file(struct hypfs_dbfs_file *df)
@@ -92,13 +96,33 @@ void hypfs_dbfs_remove_file(struct hypfs_dbfs_file *df)
 	debugfs_remove(df->dentry);
 }
 
-int hypfs_dbfs_init(void)
+static int __init hypfs_dbfs_init(void)
 {
+	int rc = -ENODATA;
+
 	dbfs_dir = debugfs_create_dir("s390_hypfs", NULL);
-	return PTR_ERR_OR_ZERO(dbfs_dir);
-}
+	if (hypfs_diag_init())
+		goto fail_dbfs_exit;
+	if (hypfs_vm_init())
+		goto fail_hypfs_diag_exit;
+	hypfs_sprp_init();
+	if (hypfs_diag0c_init())
+		goto fail_hypfs_sprp_exit;
+	rc = hypfs_fs_init();
+	if (rc)
+		goto fail_hypfs_diag0c_exit;
+	return 0;
 
-void hypfs_dbfs_exit(void)
-{
+fail_hypfs_diag0c_exit:
+	hypfs_diag0c_exit();
+fail_hypfs_sprp_exit:
+	hypfs_sprp_exit();
+	hypfs_vm_exit();
+fail_hypfs_diag_exit:
+	hypfs_diag_exit();
+	pr_err("Initialization of hypfs failed with rc=%i\n", rc);
+fail_dbfs_exit:
 	debugfs_remove(dbfs_dir);
+	return rc;
 }
+device_initcall(hypfs_dbfs_init)