Commit 98efb4eb authored by David Sterba's avatar David Sterba
Browse files

btrfs: use helper sizeof_field in struct accessors 



There's a helper for obtaining size of a struct member, we can use it
instead of open coding the pointer magic.

Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 16c3a476

fs/btrfs/accessors.h

+11 −12
Original line number Diff line number Diff line
@@ -3,6 +3,8 @@ 
#ifndef BTRFS_ACCESSORS_H

#define BTRFS_ACCESSORS_H



#include <linux/stddef.h>



struct btrfs_map_token {

	struct extent_buffer *eb;

	char *kaddr;
@@ -34,13 +36,13 @@ static inline void put_unaligned_le8(u8 val, void *p) 
	read_extent_buffer(eb, (char *)(result),			\

			   ((unsigned long)(ptr)) +			\

			    offsetof(type, member),			\

			   sizeof(((type *)0)->member)))

			    sizeof_field(type, member)))



#define write_eb_member(eb, ptr, type, member, result) (\

	write_extent_buffer(eb, (char *)(result),			\

			   ((unsigned long)(ptr)) +			\

			    offsetof(type, member),			\

			   sizeof(((type *)0)->member)))

			    sizeof_field(type, member)))



#define DECLARE_BTRFS_SETGET_BITS(bits)					\

u##bits btrfs_get_token_##bits(struct btrfs_map_token *token,		\
@@ -62,25 +64,25 @@ DECLARE_BTRFS_SETGET_BITS(64) 
static inline u##bits btrfs_##name(const struct extent_buffer *eb,	\

				   const type *s)			\

{									\

	static_assert(sizeof(u##bits) == sizeof(((type *)0))->member);	\

	static_assert(sizeof(u##bits) == sizeof_field(type, member));	\

	return btrfs_get_##bits(eb, s, offsetof(type, member));		\

}									\

static inline void btrfs_set_##name(const struct extent_buffer *eb, type *s, \

				    u##bits val)			\

{									\

	static_assert(sizeof(u##bits) == sizeof(((type *)0))->member);	\

	static_assert(sizeof(u##bits) == sizeof_field(type, member));	\

	btrfs_set_##bits(eb, s, offsetof(type, member), val);		\

}									\

static inline u##bits btrfs_token_##name(struct btrfs_map_token *token,	\

					 const type *s)			\

{									\

	static_assert(sizeof(u##bits) == sizeof(((type *)0))->member);	\

	static_assert(sizeof(u##bits) == sizeof_field(type, member));	\

	return btrfs_get_token_##bits(token, s, offsetof(type, member));\

}									\

static inline void btrfs_set_token_##name(struct btrfs_map_token *token,\

					  type *s, u##bits val)		\

{									\

	static_assert(sizeof(u##bits) == sizeof(((type *)0))->member);	\

	static_assert(sizeof(u##bits) == sizeof_field(type, member));	\

	btrfs_set_token_##bits(token, s, offsetof(type, member), val);	\

}
@@ -111,17 +113,14 @@ static inline void btrfs_set_##name(type *s, u##bits val) \ 
static inline u64 btrfs_device_total_bytes(const struct extent_buffer *eb,

					   struct btrfs_dev_item *s)

{

	static_assert(sizeof(u64) ==

		      sizeof(((struct btrfs_dev_item *)0))->total_bytes);

	return btrfs_get_64(eb, s, offsetof(struct btrfs_dev_item,

					    total_bytes));

	static_assert(sizeof(u64) == sizeof_field(struct btrfs_dev_item, total_bytes));

	return btrfs_get_64(eb, s, offsetof(struct btrfs_dev_item, total_bytes));

}

static inline void btrfs_set_device_total_bytes(const struct extent_buffer *eb,

						struct btrfs_dev_item *s,

						u64 val)

{

	static_assert(sizeof(u64) ==

		      sizeof(((struct btrfs_dev_item *)0))->total_bytes);

	static_assert(sizeof(u64) == sizeof_field(struct btrfs_dev_item, total_bytes));

	WARN_ON(!IS_ALIGNED(val, eb->fs_info->sectorsize));

	btrfs_set_64(eb, s, offsetof(struct btrfs_dev_item, total_bytes), val);

}