[PATCH] Revert "mtd: switch open_mtd_by_chdev() to use of vfs_stat()"

[Richard Weinberger]

This reverts commit 87f15d4add758fb7fc76655721af94be57a4c17d.

vfs_stat() can only be used on user supplied buffers.

Cc: Al Viro <v...@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <rich...@nod.at>
---
 drivers/mtd/ubi/build.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 16baeb5..7091fca 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -1147,19 +1147,22 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
  */
 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
 {
-       struct kstat stat;
-       int err, minor;
+       int err, major, minor, mode;
+       struct path path;
 
        /* Probably this is an MTD character device node path */
-       err = vfs_stat(mtd_dev, &stat);
+       err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
        if (err)
                return ERR_PTR(err);
 
        /* MTD device number is defined by the major / minor numbers */
-       if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))
+       major = imajor(d_backing_inode(path.dentry));
+       minor = iminor(d_backing_inode(path.dentry));
+       mode = d_backing_inode(path.dentry)->i_mode;
+       path_put(&path);
+       if (major != MTD_CHAR_MAJOR || !S_ISCHR(mode))
                return ERR_PTR(-EINVAL);
 
-       minor = MINOR(stat.rdev);
        if (minor & 1)
                /*
                 * Just do not think the "/dev/mtdrX" devices support is need,
-- 
2.7.3