sysfs: merge sysfs_elem_bin_attr into sysfs_elem_attr

3124eb1679 ("sysfs: merge regular and bin file handling") folded bin
file handling into regular file handling.  Among other things, bin
file now shares the same open path including sysfs_open_dirent
association using sysfs_dirent->s_attr.open.  This is buggy because
->s_bin_attr lives in the same union and doesn't have the field.  This
bug doesn't trigger because sysfs_elem_bin_attr doesn't have an active
field at the conflicting position.  It does have a field "buffers" but
it isn't used anymore.

This patch collapses sysfs_elem_bin_attr into sysfs_elem_attr so that
the bin_attr is accessed through ->s_attr.bin_attr which lives with
->s_attr.attr in an anonymous union.  The code paths already assume
bin_attr contains attr as the first element, so this doesn't add any
more assumptions while making it explicit that the two types are
handled together.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 4 insertions, 7 deletions

diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 94ac8fa34dd4..c095d952f3a5 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -29,15 +29,13 @@ struct sysfs_elem_symlink {
 };
 
 struct sysfs_elem_attr {
-	struct attribute	*attr;
+	union {
+		struct attribute	*attr;
+		struct bin_attribute	*bin_attr;
+	};
 	struct sysfs_open_dirent *open;
 };
 
-struct sysfs_elem_bin_attr {
-	struct bin_attribute	*bin_attr;
-	struct hlist_head	buffers;
-};
-
 struct sysfs_inode_attrs {
 	struct iattr	ia_iattr;
 	void		*ia_secdata;
@@ -74,7 +72,6 @@ struct sysfs_dirent {
 		struct sysfs_elem_dir		s_dir;
 		struct sysfs_elem_symlink	s_symlink;
 		struct sysfs_elem_attr		s_attr;
-		struct sysfs_elem_bin_attr	s_bin_attr;
 	};
 
 	unsigned short		s_flags;