mtdchar: cdev lock_kernel() pushdown

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 5d3ac512ce169f1f4efc8de2cde7ae6ca21c6148..129d429cd2da5abc55ea1aa9c97a21041a5c85ff 100644 (file)
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
+#include <linux/smp_lock.h>
 
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/compatmac.h>
@@ -86,6 +87,7 @@ static int mtd_open(struct inode *inode, struct file *file)
 {
        int minor = iminor(inode);
        int devnum = minor >> 1;
+       int ret = 0;
        struct mtd_info *mtd;
        struct mtd_file_info *mfi;
 
@@ -98,31 +100,39 @@ static int mtd_open(struct inode *inode, struct file *file)
        if ((file->f_mode & 2) && (minor & 1))
                return -EACCES;
 
+       lock_kernel();
        mtd = get_mtd_device(NULL, devnum);
 
-       if (IS_ERR(mtd))
-               return PTR_ERR(mtd);
+       if (IS_ERR(mtd)) {
+               ret = PTR_ERR(mtd);
+               goto out;
+       }
 
        if (MTD_ABSENT == mtd->type) {
                put_mtd_device(mtd);
-               return -ENODEV;
+               ret = -ENODEV;
+               goto out;
        }
 
        /* You can't open it RW if it's not a writeable device */
        if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
                put_mtd_device(mtd);
-               return -EACCES;
+               ret = -EACCES;
+               goto out;
        }
 
        mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
        if (!mfi) {
                put_mtd_device(mtd);
-               return -ENOMEM;
+               ret = -ENOMEM;
+               goto out;
        }
        mfi->mtd = mtd;
        file->private_data = mfi;
 
-       return 0;
+out:
+       unlock_kernel();
+       return ret;
 } /* mtd_open */
 
 /*====================================================================*/