nilfs2: clarify byte offset in super block format

This inserts comments indicating hexadecimal offset in declaration of
nilfs_super_block structure so that people can know offset of its
fields without counting from the head.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

diff --git a/include/linux/nilfs2_fs.h b/include/linux/nilfs2_fs.h
index 8c2c6116e788994cf1f95aba1c771c92fe384a4d..cc3465e5be3817cccf93bbd1e9953717bd106fbb 100644 (file)
--- a/include/linux/nilfs2_fs.h
+++ b/include/linux/nilfs2_fs.h
@@ -160,7 +160,7 @@ struct nilfs_super_root {
  * struct nilfs_super_block - structure of super block on disk
  */
 struct nilfs_super_block {
-       __le32  s_rev_level;            /* Revision level */
+/*00*/ __le32  s_rev_level;            /* Revision level */
        __le16  s_minor_rev_level;      /* minor revision level */
        __le16  s_magic;                /* Magic signature */
 
@@ -169,47 +169,47 @@ struct nilfs_super_block {
                                           is excluded. */
        __le16  s_flags;                /* flags */
        __le32  s_crc_seed;             /* Seed value of CRC calculation */
-       __le32  s_sum;                  /* Check sum of super block */
+/*10*/ __le32  s_sum;                  /* Check sum of super block */
 
        __le32  s_log_block_size;       /* Block size represented as follows
                                           blocksize =
                                               1 << (s_log_block_size + 10) */
        __le64  s_nsegments;            /* Number of segments in filesystem */
-       __le64  s_dev_size;             /* block device size in bytes */
+/*20*/ __le64  s_dev_size;             /* block device size in bytes */
        __le64  s_first_data_block;     /* 1st seg disk block number */
-       __le32  s_blocks_per_segment;   /* number of blocks per full segment */
+/*30*/ __le32  s_blocks_per_segment;   /* number of blocks per full segment */
        __le32  s_r_segments_percentage; /* Reserved segments percentage */
 
        __le64  s_last_cno;             /* Last checkpoint number */
-       __le64  s_last_pseg;            /* disk block addr pseg written last */
+/*40*/ __le64  s_last_pseg;            /* disk block addr pseg written last */
        __le64  s_last_seq;             /* seq. number of seg written last */
-       __le64  s_free_blocks_count;    /* Free blocks count */
+/*50*/ __le64  s_free_blocks_count;    /* Free blocks count */
 
        __le64  s_ctime;                /* Creation time (execution time of
                                           newfs) */
-       __le64  s_mtime;                /* Mount time */
+/*60*/ __le64  s_mtime;                /* Mount time */
        __le64  s_wtime;                /* Write time */
-       __le16  s_mnt_count;            /* Mount count */
+/*70*/ __le16  s_mnt_count;            /* Mount count */
        __le16  s_max_mnt_count;        /* Maximal mount count */
        __le16  s_state;                /* File system state */
        __le16  s_errors;               /* Behaviour when detecting errors */
        __le64  s_lastcheck;            /* time of last check */
 
-       __le32  s_checkinterval;        /* max. time between checks */
+/*80*/ __le32  s_checkinterval;        /* max. time between checks */
        __le32  s_creator_os;           /* OS */
        __le16  s_def_resuid;           /* Default uid for reserved blocks */
        __le16  s_def_resgid;           /* Default gid for reserved blocks */
        __le32  s_first_ino;            /* First non-reserved inode */
 
-       __le16  s_inode_size;           /* Size of an inode */
+/*90*/ __le16  s_inode_size;           /* Size of an inode */
        __le16  s_dat_entry_size;       /* Size of a dat entry */
        __le16  s_checkpoint_size;      /* Size of a checkpoint */
        __le16  s_segment_usage_size;   /* Size of a segment usage */
 
-       __u8    s_uuid[16];             /* 128-bit uuid for volume */
-       char    s_volume_name[80];      /* volume name */
+/*98*/ __u8    s_uuid[16];             /* 128-bit uuid for volume */
+/*A8*/ char    s_volume_name[80];      /* volume name */
 
-       __le32  s_c_interval;           /* Commit interval of segment */
+/*F8*/ __le32  s_c_interval;           /* Commit interval of segment */
        __le32  s_c_block_max;          /* Threshold of data amount for
                                           the segment construction */
        __u32   s_reserved[192];        /* padding to the end of the block */