From: Gao Xiang <gaoxiang25@xxxxxxxxxx> As Christoph suggested [1], "Please remove all the byte offset comments. that is something that can easily be checked with gdb or pahole." [1] https://lore.kernel.org/r/20190829095954.GB20598@xxxxxxxxxxxxx/ Reported-by: Christoph Hellwig <hch@xxxxxxxxxxxxx> Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx> --- fs/erofs/erofs_fs.h | 105 +++++++++++++++++++++++--------------------- 1 file changed, 54 insertions(+), 51 deletions(-) diff --git a/fs/erofs/erofs_fs.h b/fs/erofs/erofs_fs.h index afa7d45ca958..49335fff9d65 100644 --- a/fs/erofs/erofs_fs.h +++ b/fs/erofs/erofs_fs.h @@ -17,27 +17,28 @@ #define EROFS_REQUIREMENT_LZ4_0PADDING 0x00000001 #define EROFS_ALL_REQUIREMENTS EROFS_REQUIREMENT_LZ4_0PADDING +/* 128-byte erofs on-disk super block */ struct erofs_super_block { -/* 0 */__le32 magic; /* in the little endian */ -/* 4 */__le32 checksum; /* crc32c(super_block) */ -/* 8 */__le32 features; /* (aka. feature_compat) */ -/* 12 */__u8 blkszbits; /* support block_size == PAGE_SIZE only */ -/* 13 */__u8 reserved; - -/* 14 */__le16 root_nid; -/* 16 */__le64 inos; /* total valid ino # (== f_files - f_favail) */ - -/* 24 */__le64 build_time; /* inode v1 time derivation */ -/* 32 */__le32 build_time_nsec; -/* 36 */__le32 blocks; /* used for statfs */ -/* 40 */__le32 meta_blkaddr; -/* 44 */__le32 xattr_blkaddr; -/* 48 */__u8 uuid[16]; /* 128-bit uuid for volume */ -/* 64 */__u8 volume_name[16]; /* volume name */ -/* 80 */__le32 requirements; /* (aka. feature_incompat) */ - -/* 84 */__u8 reserved2[44]; -} __packed; /* 128 bytes */ + __le32 magic; /* file system magic number */ + __le32 checksum; /* crc32c(super_block) */ + __le32 features; /* (aka. feature_compat) */ + __u8 blkszbits; /* support block_size == PAGE_SIZE only */ + __u8 reserved; + + __le16 root_nid; /* nid of root directory */ + __le64 inos; /* total valid ino # (== f_files - f_favail) */ + + __le64 build_time; /* inode v1 time derivation */ + __le32 build_time_nsec; /* inode v1 time derivation in nano scale */ + __le32 blocks; /* used for statfs */ + __le32 meta_blkaddr; /* start block address of metadata area */ + __le32 xattr_blkaddr; /* start block address of shared xattr area */ + __u8 uuid[16]; /* 128-bit uuid for volume */ + __u8 volume_name[16]; /* volume name */ + __le32 requirements; /* (aka. feature_incompat) */ + + __u8 reserved2[44]; +} __packed; /* * erofs inode data mapping: @@ -73,16 +74,17 @@ static inline bool erofs_inode_is_data_compressed(unsigned int datamode) #define EROFS_I_VERSION_BIT 0 #define EROFS_I_DATA_MAPPING_BIT 1 +/* 32-byte reduced form of an ondisk inode */ struct erofs_inode_v1 { -/* 0 */__le16 i_advise; + __le16 i_advise; /* inode hints */ /* 1 header + n-1 * 4 bytes inline xattr to keep continuity */ -/* 2 */__le16 i_xattr_icount; -/* 4 */__le16 i_mode; -/* 6 */__le16 i_nlink; -/* 8 */__le32 i_size; -/* 12 */__le32 i_reserved; -/* 16 */union { + __le16 i_xattr_icount; + __le16 i_mode; + __le16 i_nlink; + __le32 i_size; + __le32 i_reserved; + union { /* file total compressed blocks for data mapping 1 */ __le32 compressed_blocks; __le32 raw_blkaddr; @@ -90,10 +92,10 @@ struct erofs_inode_v1 { /* for device files, used to indicate old/new device # */ __le32 rdev; } i_u __packed; -/* 20 */__le32 i_ino; /* only used for 32-bit stat compatibility */ -/* 24 */__le16 i_uid; -/* 26 */__le16 i_gid; -/* 28 */__le32 i_reserved2; + __le32 i_ino; /* only used for 32-bit stat compatibility */ + __le16 i_uid; + __le16 i_gid; + __le32 i_reserved2; } __packed; /* 32 bytes on-disk inode */ @@ -101,15 +103,16 @@ struct erofs_inode_v1 { /* 64 bytes on-disk inode */ #define EROFS_INODE_LAYOUT_V2 1 +/* 64-byte complete form of an ondisk inode */ struct erofs_inode_v2 { -/* 0 */__le16 i_advise; + __le16 i_advise; /* inode hints */ /* 1 header + n-1 * 4 bytes inline xattr to keep continuity */ -/* 2 */__le16 i_xattr_icount; -/* 4 */__le16 i_mode; -/* 6 */__le16 i_reserved; -/* 8 */__le64 i_size; -/* 16 */union { + __le16 i_xattr_icount; + __le16 i_mode; + __le16 i_reserved; + __le64 i_size; + union { /* file total compressed blocks for data mapping 1 */ __le32 compressed_blocks; __le32 raw_blkaddr; @@ -119,15 +122,15 @@ struct erofs_inode_v2 { } i_u __packed; /* only used for 32-bit stat compatibility */ -/* 20 */__le32 i_ino; - -/* 24 */__le32 i_uid; -/* 28 */__le32 i_gid; -/* 32 */__le64 i_ctime; -/* 40 */__le32 i_ctime_nsec; -/* 44 */__le32 i_nlink; -/* 48 */__u8 i_reserved2[16]; -} __packed; /* 64 bytes */ + __le32 i_ino; + + __le32 i_uid; + __le32 i_gid; + __le64 i_ctime; + __le32 i_ctime_nsec; + __le32 i_nlink; + __u8 i_reserved2[16]; +} __packed; #define EROFS_MAX_SHARED_XATTRS (128) /* h_shared_count between 129 ... 255 are special # */ @@ -264,7 +267,7 @@ struct z_erofs_vle_decompressed_index { * [1] - pointing to the tail cluster */ __le16 delta[2]; - } di_u __packed; /* 8 bytes */ + } di_u __packed; } __packed; #define Z_EROFS_VLE_LEGACY_INDEX_ALIGN(size) \ @@ -273,10 +276,10 @@ struct z_erofs_vle_decompressed_index { /* dirent sorts in alphabet order, thus we can do binary search */ struct erofs_dirent { - __le64 nid; /* 0, node number */ - __le16 nameoff; /* 8, start offset of file name */ - __u8 file_type; /* 10, file type */ - __u8 reserved; /* 11, reserved */ + __le64 nid; /* node number */ + __le16 nameoff; /* start offset of file name */ + __u8 file_type; /* file type */ + __u8 reserved; /* reserved */ } __packed; /* -- 2.17.1
