[PATCH 04/19] f2fs: add feature facility in superblock

[Jaegeuk Kim <jaegeuk@kernel.org>]

This patch introduces a feature in superblock, which will indicate any new
features for f2fs.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/f2fs.h          | 7 +++++++
 include/linux/f2fs_fs.h | 3 ++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index cd9748a..e1dd986 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -70,6 +70,13 @@ struct f2fs_mount_info {
 	unsigned int	opt;
 };
 
+#define F2FS_HAS_FEATURE(sb, mask)					\
+	((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0)
+#define F2FS_SET_FEATURE(sb, mask)					\
+	F2FS_SB(sb)->raw_super->feature |= cpu_to_le32(mask)
+#define F2FS_CLEAR_FEATURE(sb, mask)					\
+	F2FS_SB(sb)->raw_super->feature &= ~cpu_to_le32(mask)
+
 #define CRCPOLY_LE 0xedb88320
 
 static inline __u32 f2fs_crc32(void *buf, size_t len)
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index 8d345c2..d44e97f 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -90,7 +90,8 @@ struct f2fs_super_block {
 	__le32 cp_payload;
 	__u8 version[VERSION_LEN];	/* the kernel version */
 	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
-	__u8 reserved[892];		/* valid reserved region */
+	__le32 feature;			/* defined features */
+	__u8 reserved[888];		/* valid reserved region */
 } __packed;
 
 /*
-- 
2.1.1


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