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author | Jaegeuk Kim <jaegeuk.kim@samsung.com> | 2012-11-02 17:06:26 +0900 |
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committer | Jaegeuk Kim <jaegeuk.kim@samsung.com> | 2012-12-11 13:43:40 +0900 |
commit | dd31866b0d55c9b70722ebad6ccd643223d9269e (patch) | |
tree | d5b28940dc4fbb9a83dc7386a00621850cf54235 /include/linux | |
parent | 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 (diff) | |
download | op-kernel-dev-dd31866b0d55c9b70722ebad6ccd643223d9269e.zip op-kernel-dev-dd31866b0d55c9b70722ebad6ccd643223d9269e.tar.gz |
f2fs: add on-disk layout
This adds a header file describing the on-disk layout of f2fs.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Chul Lee <chur.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/f2fs_fs.h | 410 |
1 files changed, 410 insertions, 0 deletions
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h new file mode 100644 index 0000000..1429ece --- /dev/null +++ b/include/linux/f2fs_fs.h @@ -0,0 +1,410 @@ +/** + * include/linux/f2fs_fs.h + * + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef _LINUX_F2FS_FS_H +#define _LINUX_F2FS_FS_H + +#include <linux/pagemap.h> +#include <linux/types.h> + +#define F2FS_SUPER_OFFSET 1024 /* byte-size offset */ +#define F2FS_LOG_SECTOR_SIZE 9 /* 9 bits for 512 byte */ +#define F2FS_LOG_SECTORS_PER_BLOCK 3 /* 4KB: F2FS_BLKSIZE */ +#define F2FS_BLKSIZE 4096 /* support only 4KB block */ +#define F2FS_MAX_EXTENSION 64 /* # of extension entries */ + +#define NULL_ADDR 0x0U +#define NEW_ADDR -1U + +#define F2FS_ROOT_INO(sbi) (sbi->root_ino_num) +#define F2FS_NODE_INO(sbi) (sbi->node_ino_num) +#define F2FS_META_INO(sbi) (sbi->meta_ino_num) + +/* This flag is used by node and meta inodes, and by recovery */ +#define GFP_F2FS_ZERO (GFP_NOFS | __GFP_ZERO) + +/* + * For further optimization on multi-head logs, on-disk layout supports maximum + * 16 logs by default. The number, 16, is expected to cover all the cases + * enoughly. The implementaion currently uses no more than 6 logs. + * Half the logs are used for nodes, and the other half are used for data. + */ +#define MAX_ACTIVE_LOGS 16 +#define MAX_ACTIVE_NODE_LOGS 8 +#define MAX_ACTIVE_DATA_LOGS 8 + +/* + * For superblock + */ +struct f2fs_super_block { + __le32 magic; /* Magic Number */ + __le16 major_ver; /* Major Version */ + __le16 minor_ver; /* Minor Version */ + __le32 log_sectorsize; /* log2 sector size in bytes */ + __le32 log_sectors_per_block; /* log2 # of sectors per block */ + __le32 log_blocksize; /* log2 block size in bytes */ + __le32 log_blocks_per_seg; /* log2 # of blocks per segment */ + __le32 segs_per_sec; /* # of segments per section */ + __le32 secs_per_zone; /* # of sections per zone */ + __le32 checksum_offset; /* checksum offset inside super block */ + __le64 block_count; /* total # of user blocks */ + __le32 section_count; /* total # of sections */ + __le32 segment_count; /* total # of segments */ + __le32 segment_count_ckpt; /* # of segments for checkpoint */ + __le32 segment_count_sit; /* # of segments for SIT */ + __le32 segment_count_nat; /* # of segments for NAT */ + __le32 segment_count_ssa; /* # of segments for SSA */ + __le32 segment_count_main; /* # of segments for main area */ + __le32 segment0_blkaddr; /* start block address of segment 0 */ + __le32 cp_blkaddr; /* start block address of checkpoint */ + __le32 sit_blkaddr; /* start block address of SIT */ + __le32 nat_blkaddr; /* start block address of NAT */ + __le32 ssa_blkaddr; /* start block address of SSA */ + __le32 main_blkaddr; /* start block address of main area */ + __le32 root_ino; /* root inode number */ + __le32 node_ino; /* node inode number */ + __le32 meta_ino; /* meta inode number */ + __u8 uuid[16]; /* 128-bit uuid for volume */ + __le16 volume_name[512]; /* volume name */ + __le32 extension_count; /* # of extensions below */ + __u8 extension_list[F2FS_MAX_EXTENSION][8]; /* extension array */ +} __packed; + +/* + * For checkpoint + */ +#define CP_ERROR_FLAG 0x00000008 +#define CP_COMPACT_SUM_FLAG 0x00000004 +#define CP_ORPHAN_PRESENT_FLAG 0x00000002 +#define CP_UMOUNT_FLAG 0x00000001 + +struct f2fs_checkpoint { + __le64 checkpoint_ver; /* checkpoint block version number */ + __le64 user_block_count; /* # of user blocks */ + __le64 valid_block_count; /* # of valid blocks in main area */ + __le32 rsvd_segment_count; /* # of reserved segments for gc */ + __le32 overprov_segment_count; /* # of overprovision segments */ + __le32 free_segment_count; /* # of free segments in main area */ + + /* information of current node segments */ + __le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS]; + __le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS]; + /* information of current data segments */ + __le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS]; + __le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS]; + __le32 ckpt_flags; /* Flags : umount and journal_present */ + __le32 cp_pack_total_block_count; /* total # of one cp pack */ + __le32 cp_pack_start_sum; /* start block number of data summary */ + __le32 valid_node_count; /* Total number of valid nodes */ + __le32 valid_inode_count; /* Total number of valid inodes */ + __le32 next_free_nid; /* Next free node number */ + __le32 sit_ver_bitmap_bytesize; /* Default value 64 */ + __le32 nat_ver_bitmap_bytesize; /* Default value 256 */ + __le32 checksum_offset; /* checksum offset inside cp block */ + __le64 elapsed_time; /* mounted time */ + /* allocation type of current segment */ + unsigned char alloc_type[MAX_ACTIVE_LOGS]; + + /* SIT and NAT version bitmap */ + unsigned char sit_nat_version_bitmap[1]; +} __packed; + +/* + * For orphan inode management + */ +#define F2FS_ORPHANS_PER_BLOCK 1020 + +struct f2fs_orphan_block { + __le32 ino[F2FS_ORPHANS_PER_BLOCK]; /* inode numbers */ + __le32 reserved; /* reserved */ + __le16 blk_addr; /* block index in current CP */ + __le16 blk_count; /* Number of orphan inode blocks in CP */ + __le32 entry_count; /* Total number of orphan nodes in current CP */ + __le32 check_sum; /* CRC32 for orphan inode block */ +} __packed; + +/* + * For NODE structure + */ +struct f2fs_extent { + __le32 fofs; /* start file offset of the extent */ + __le32 blk_addr; /* start block address of the extent */ + __le32 len; /* lengh of the extent */ +} __packed; + +#define F2FS_MAX_NAME_LEN 256 +#define ADDRS_PER_INODE 923 /* Address Pointers in an Inode */ +#define ADDRS_PER_BLOCK 1018 /* Address Pointers in a Direct Block */ +#define NIDS_PER_BLOCK 1018 /* Node IDs in an Indirect Block */ + +struct f2fs_inode { + __le16 i_mode; /* file mode */ + __u8 i_advise; /* file hints */ + __u8 i_reserved; /* reserved */ + __le32 i_uid; /* user ID */ + __le32 i_gid; /* group ID */ + __le32 i_links; /* links count */ + __le64 i_size; /* file size in bytes */ + __le64 i_blocks; /* file size in blocks */ + __le64 i_atime; /* access time */ + __le64 i_ctime; /* change time */ + __le64 i_mtime; /* modification time */ + __le32 i_atime_nsec; /* access time in nano scale */ + __le32 i_ctime_nsec; /* change time in nano scale */ + __le32 i_mtime_nsec; /* modification time in nano scale */ + __le32 i_generation; /* file version (for NFS) */ + __le32 i_current_depth; /* only for directory depth */ + __le32 i_xattr_nid; /* nid to save xattr */ + __le32 i_flags; /* file attributes */ + __le32 i_pino; /* parent inode number */ + __le32 i_namelen; /* file name length */ + __u8 i_name[F2FS_MAX_NAME_LEN]; /* file name for SPOR */ + + struct f2fs_extent i_ext; /* caching a largest extent */ + + __le32 i_addr[ADDRS_PER_INODE]; /* Pointers to data blocks */ + + __le32 i_nid[5]; /* direct(2), indirect(2), + double_indirect(1) node id */ +} __packed; + +struct direct_node { + __le32 addr[ADDRS_PER_BLOCK]; /* array of data block address */ +} __packed; + +struct indirect_node { + __le32 nid[NIDS_PER_BLOCK]; /* array of data block address */ +} __packed; + +enum { + COLD_BIT_SHIFT = 0, + FSYNC_BIT_SHIFT, + DENT_BIT_SHIFT, + OFFSET_BIT_SHIFT +}; + +struct node_footer { + __le32 nid; /* node id */ + __le32 ino; /* inode nunmber */ + __le32 flag; /* include cold/fsync/dentry marks and offset */ + __le64 cp_ver; /* checkpoint version */ + __le32 next_blkaddr; /* next node page block address */ +} __packed; + +struct f2fs_node { + /* can be one of three types: inode, direct, and indirect types */ + union { + struct f2fs_inode i; + struct direct_node dn; + struct indirect_node in; + }; + struct node_footer footer; +} __packed; + +/* + * For NAT entries + */ +#define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry)) + +struct f2fs_nat_entry { + __u8 version; /* latest version of cached nat entry */ + __le32 ino; /* inode number */ + __le32 block_addr; /* block address */ +} __packed; + +struct f2fs_nat_block { + struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK]; +} __packed; + +/* + * For SIT entries + * + * Each segment is 2MB in size by default so that a bitmap for validity of + * there-in blocks should occupy 64 bytes, 512 bits. + * Not allow to change this. + */ +#define SIT_VBLOCK_MAP_SIZE 64 +#define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry)) + +/* + * Note that f2fs_sit_entry->vblocks has the following bit-field information. + * [15:10] : allocation type such as CURSEG_XXXX_TYPE + * [9:0] : valid block count + */ +#define SIT_VBLOCKS_SHIFT 10 +#define SIT_VBLOCKS_MASK ((1 << SIT_VBLOCKS_SHIFT) - 1) +#define GET_SIT_VBLOCKS(raw_sit) \ + (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK) +#define GET_SIT_TYPE(raw_sit) \ + ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK) \ + >> SIT_VBLOCKS_SHIFT) + +struct f2fs_sit_entry { + __le16 vblocks; /* reference above */ + __u8 valid_map[SIT_VBLOCK_MAP_SIZE]; /* bitmap for valid blocks */ + __le64 mtime; /* segment age for cleaning */ +} __packed; + +struct f2fs_sit_block { + struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK]; +} __packed; + +/* + * For segment summary + * + * One summary block contains exactly 512 summary entries, which represents + * exactly 2MB segment by default. Not allow to change the basic units. + * + * NOTE: For initializing fields, you must use set_summary + * + * - If data page, nid represents dnode's nid + * - If node page, nid represents the node page's nid. + * + * The ofs_in_node is used by only data page. It represents offset + * from node's page's beginning to get a data block address. + * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node) + */ +#define ENTRIES_IN_SUM 512 +#define SUMMARY_SIZE (sizeof(struct f2fs_summary)) +#define SUM_FOOTER_SIZE (sizeof(struct summary_footer)) +#define SUM_ENTRY_SIZE (SUMMARY_SIZE * ENTRIES_IN_SUM) + +/* a summary entry for a 4KB-sized block in a segment */ +struct f2fs_summary { + __le32 nid; /* parent node id */ + union { + __u8 reserved[3]; + struct { + __u8 version; /* node version number */ + __le16 ofs_in_node; /* block index in parent node */ + } __packed; + }; +} __packed; + +/* summary block type, node or data, is stored to the summary_footer */ +#define SUM_TYPE_NODE (1) +#define SUM_TYPE_DATA (0) + +struct summary_footer { + unsigned char entry_type; /* SUM_TYPE_XXX */ + __u32 check_sum; /* summary checksum */ +} __packed; + +#define SUM_JOURNAL_SIZE (PAGE_CACHE_SIZE - SUM_FOOTER_SIZE -\ + SUM_ENTRY_SIZE) +#define NAT_JOURNAL_ENTRIES ((SUM_JOURNAL_SIZE - 2) /\ + sizeof(struct nat_journal_entry)) +#define NAT_JOURNAL_RESERVED ((SUM_JOURNAL_SIZE - 2) %\ + sizeof(struct nat_journal_entry)) +#define SIT_JOURNAL_ENTRIES ((SUM_JOURNAL_SIZE - 2) /\ + sizeof(struct sit_journal_entry)) +#define SIT_JOURNAL_RESERVED ((SUM_JOURNAL_SIZE - 2) %\ + sizeof(struct sit_journal_entry)) +/* + * frequently updated NAT/SIT entries can be stored in the spare area in + * summary blocks + */ +enum { + NAT_JOURNAL = 0, + SIT_JOURNAL +}; + +struct nat_journal_entry { + __le32 nid; + struct f2fs_nat_entry ne; +} __packed; + +struct nat_journal { + struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES]; + __u8 reserved[NAT_JOURNAL_RESERVED]; +} __packed; + +struct sit_journal_entry { + __le32 segno; + struct f2fs_sit_entry se; +} __packed; + +struct sit_journal { + struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES]; + __u8 reserved[SIT_JOURNAL_RESERVED]; +} __packed; + +/* 4KB-sized summary block structure */ +struct f2fs_summary_block { + struct f2fs_summary entries[ENTRIES_IN_SUM]; + union { + __le16 n_nats; + __le16 n_sits; + }; + /* spare area is used by NAT or SIT journals */ + union { + struct nat_journal nat_j; + struct sit_journal sit_j; + }; + struct summary_footer footer; +} __packed; + +/* + * For directory operations + */ +#define F2FS_DOT_HASH 0 +#define F2FS_DDOT_HASH F2FS_DOT_HASH +#define F2FS_MAX_HASH (~((0x3ULL) << 62)) +#define F2FS_HASH_COL_BIT ((0x1ULL) << 63) + +typedef __le32 f2fs_hash_t; + +/* One directory entry slot covers 8bytes-long file name */ +#define F2FS_NAME_LEN 8 + +/* the number of dentry in a block */ +#define NR_DENTRY_IN_BLOCK 214 + +/* MAX level for dir lookup */ +#define MAX_DIR_HASH_DEPTH 63 + +#define SIZE_OF_DIR_ENTRY 11 /* by byte */ +#define SIZE_OF_DENTRY_BITMAP ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \ + BITS_PER_BYTE) +#define SIZE_OF_RESERVED (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \ + F2FS_NAME_LEN) * \ + NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP)) + +/* One directory entry slot representing F2FS_NAME_LEN-sized file name */ +struct f2fs_dir_entry { + __le32 hash_code; /* hash code of file name */ + __le32 ino; /* inode number */ + __le16 name_len; /* lengh of file name */ + __u8 file_type; /* file type */ +} __packed; + +/* 4KB-sized directory entry block */ +struct f2fs_dentry_block { + /* validity bitmap for directory entries in each block */ + __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP]; + __u8 reserved[SIZE_OF_RESERVED]; + struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK]; + __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_NAME_LEN]; +} __packed; + +/* file types used in inode_info->flags */ +enum { + F2FS_FT_UNKNOWN, + F2FS_FT_REG_FILE, + F2FS_FT_DIR, + F2FS_FT_CHRDEV, + F2FS_FT_BLKDEV, + F2FS_FT_FIFO, + F2FS_FT_SOCK, + F2FS_FT_SYMLINK, + F2FS_FT_MAX +}; + +#endif /* _LINUX_F2FS_FS_H */ |