drivers/s390: cdev lock_kernel() pushdown

[firefly-linux-kernel-4.4.55.git] / drivers / s390 / char / vmur.c

diff --git a/drivers/s390/char/vmur.c b/drivers/s390/char/vmur.c
index 83ae9a852f00c2dc5c4e2fc9be7eb81e974770de..61549987ed70b0b6967923639b3230ee8332d465 100644 (file)
--- a/drivers/s390/char/vmur.c
+++ b/drivers/s390/char/vmur.c
@@ -9,6 +9,7 @@
  */
 
 #include <linux/cdev.h>
+#include <linux/smp_lock.h>
 
 #include <asm/uaccess.h>
 #include <asm/cio.h>
@@ -668,7 +669,7 @@ static int ur_open(struct inode *inode, struct file *file)
 
        if (accmode == O_RDWR)
                return -EACCES;
-
+       lock_kernel();
        /*
         * We treat the minor number as the devno of the ur device
         * to find in the driver tree.
@@ -676,8 +677,10 @@ static int ur_open(struct inode *inode, struct file *file)
        devno = MINOR(file->f_dentry->d_inode->i_rdev);
 
        urd = urdev_get_from_devno(devno);
-       if (!urd)
-               return -ENXIO;
+       if (!urd) {
+               rc = -ENXIO;
+               goto out;
+       }
 
        spin_lock(&urd->open_lock);
        while (urd->open_flag) {
@@ -720,6 +723,7 @@ static int ur_open(struct inode *inode, struct file *file)
                goto fail_urfile_free;
        urf->file_reclen = rc;
        file->private_data = urf;
+       unlock_kernel();
        return 0;
 
 fail_urfile_free:
@@ -730,6 +734,8 @@ fail_unlock:
        spin_unlock(&urd->open_lock);
 fail_put:
        urdev_put(urd);
+out:
+       unlock_kernel();
        return rc;
 }