| /* |
| * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc. |
| * Copyright (c) 2013 Red Hat, Inc. |
| * All Rights Reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it would be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| #ifndef __XFS_DA_FORMAT_H__ |
| #define __XFS_DA_FORMAT_H__ |
| |
| /* |
| * This structure is common to both leaf nodes and non-leaf nodes in the Btree. |
| * |
| * It is used to manage a doubly linked list of all blocks at the same |
| * level in the Btree, and to identify which type of block this is. |
| */ |
| #define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */ |
| #define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */ |
| #define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */ |
| #define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */ |
| |
| typedef struct xfs_da_blkinfo { |
| __be32 forw; /* previous block in list */ |
| __be32 back; /* following block in list */ |
| __be16 magic; /* validity check on block */ |
| __be16 pad; /* unused */ |
| } xfs_da_blkinfo_t; |
| |
| /* |
| * CRC enabled directory structure types |
| * |
| * The headers change size for the additional verification information, but |
| * otherwise the tree layouts and contents are unchanged. Hence the da btree |
| * code can use the struct xfs_da_blkinfo for manipulating the tree links and |
| * magic numbers without modification for both v2 and v3 nodes. |
| */ |
| #define XFS_DA3_NODE_MAGIC 0x3ebe /* magic number: non-leaf blocks */ |
| #define XFS_ATTR3_LEAF_MAGIC 0x3bee /* magic number: attribute leaf blks */ |
| #define XFS_DIR3_LEAF1_MAGIC 0x3df1 /* magic number: v2 dirlf single blks */ |
| #define XFS_DIR3_LEAFN_MAGIC 0x3dff /* magic number: v2 dirlf multi blks */ |
| |
| struct xfs_da3_blkinfo { |
| /* |
| * the node link manipulation code relies on the fact that the first |
| * element of this structure is the struct xfs_da_blkinfo so it can |
| * ignore the differences in the rest of the structures. |
| */ |
| struct xfs_da_blkinfo hdr; |
| __be32 crc; /* CRC of block */ |
| __be64 blkno; /* first block of the buffer */ |
| __be64 lsn; /* sequence number of last write */ |
| uuid_t uuid; /* filesystem we belong to */ |
| __be64 owner; /* inode that owns the block */ |
| }; |
| |
| /* |
| * This is the structure of the root and intermediate nodes in the Btree. |
| * The leaf nodes are defined above. |
| * |
| * Entries are not packed. |
| * |
| * Since we have duplicate keys, use a binary search but always follow |
| * all match in the block, not just the first match found. |
| */ |
| #define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */ |
| |
| typedef struct xfs_da_node_hdr { |
| struct xfs_da_blkinfo info; /* block type, links, etc. */ |
| __be16 __count; /* count of active entries */ |
| __be16 __level; /* level above leaves (leaf == 0) */ |
| } xfs_da_node_hdr_t; |
| |
| struct xfs_da3_node_hdr { |
| struct xfs_da3_blkinfo info; /* block type, links, etc. */ |
| __be16 __count; /* count of active entries */ |
| __be16 __level; /* level above leaves (leaf == 0) */ |
| __be32 __pad32; |
| }; |
| |
| #define XFS_DA3_NODE_CRC_OFF (offsetof(struct xfs_da3_node_hdr, info.crc)) |
| |
| typedef struct xfs_da_node_entry { |
| __be32 hashval; /* hash value for this descendant */ |
| __be32 before; /* Btree block before this key */ |
| } xfs_da_node_entry_t; |
| |
| typedef struct xfs_da_intnode { |
| struct xfs_da_node_hdr hdr; |
| struct xfs_da_node_entry __btree[]; |
| } xfs_da_intnode_t; |
| |
| struct xfs_da3_intnode { |
| struct xfs_da3_node_hdr hdr; |
| struct xfs_da_node_entry __btree[]; |
| }; |
| |
| /* |
| * In-core version of the node header to abstract the differences in the v2 and |
| * v3 disk format of the headers. Callers need to convert to/from disk format as |
| * appropriate. |
| */ |
| struct xfs_da3_icnode_hdr { |
| __uint32_t forw; |
| __uint32_t back; |
| __uint16_t magic; |
| __uint16_t count; |
| __uint16_t level; |
| }; |
| |
| /* |
| * Directory version 2. |
| * |
| * There are 4 possible formats: |
| * - shortform - embedded into the inode |
| * - single block - data with embedded leaf at the end |
| * - multiple data blocks, single leaf+freeindex block |
| * - data blocks, node and leaf blocks (btree), freeindex blocks |
| * |
| * Note: many node blocks structures and constants are shared with the attr |
| * code and defined in xfs_da_btree.h. |
| */ |
| |
| #define XFS_DIR2_BLOCK_MAGIC 0x58443242 /* XD2B: single block dirs */ |
| #define XFS_DIR2_DATA_MAGIC 0x58443244 /* XD2D: multiblock dirs */ |
| #define XFS_DIR2_FREE_MAGIC 0x58443246 /* XD2F: free index blocks */ |
| |
| /* |
| * Directory Version 3 With CRCs. |
| * |
| * The tree formats are the same as for version 2 directories. The difference |
| * is in the block header and dirent formats. In many cases the v3 structures |
| * use v2 definitions as they are no different and this makes code sharing much |
| * easier. |
| * |
| * Also, the xfs_dir3_*() functions handle both v2 and v3 formats - if the |
| * format is v2 then they switch to the existing v2 code, or the format is v3 |
| * they implement the v3 functionality. This means the existing dir2 is a mix of |
| * xfs_dir2/xfs_dir3 calls and functions. The xfs_dir3 functions are called |
| * where there is a difference in the formats, otherwise the code is unchanged. |
| * |
| * Where it is possible, the code decides what to do based on the magic numbers |
| * in the blocks rather than feature bits in the superblock. This means the code |
| * is as independent of the external XFS code as possible as doesn't require |
| * passing struct xfs_mount pointers into places where it isn't really |
| * necessary. |
| * |
| * Version 3 includes: |
| * |
| * - a larger block header for CRC and identification purposes and so the |
| * offsets of all the structures inside the blocks are different. |
| * |
| * - new magic numbers to be able to detect the v2/v3 types on the fly. |
| */ |
| |
| #define XFS_DIR3_BLOCK_MAGIC 0x58444233 /* XDB3: single block dirs */ |
| #define XFS_DIR3_DATA_MAGIC 0x58444433 /* XDD3: multiblock dirs */ |
| #define XFS_DIR3_FREE_MAGIC 0x58444633 /* XDF3: free index blocks */ |
| |
| /* |
| * Dirents in version 3 directories have a file type field. Additions to this |
| * list are an on-disk format change, requiring feature bits. Valid values |
| * are as follows: |
| */ |
| #define XFS_DIR3_FT_UNKNOWN 0 |
| #define XFS_DIR3_FT_REG_FILE 1 |
| #define XFS_DIR3_FT_DIR 2 |
| #define XFS_DIR3_FT_CHRDEV 3 |
| #define XFS_DIR3_FT_BLKDEV 4 |
| #define XFS_DIR3_FT_FIFO 5 |
| #define XFS_DIR3_FT_SOCK 6 |
| #define XFS_DIR3_FT_SYMLINK 7 |
| #define XFS_DIR3_FT_WHT 8 |
| |
| #define XFS_DIR3_FT_MAX 9 |
| |
| /* |
| * Byte offset in data block and shortform entry. |
| */ |
| typedef __uint16_t xfs_dir2_data_off_t; |
| #define NULLDATAOFF 0xffffU |
| typedef uint xfs_dir2_data_aoff_t; /* argument form */ |
| |
| /* |
| * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t. |
| * Only need 16 bits, this is the byte offset into the single block form. |
| */ |
| typedef struct { __uint8_t i[2]; } __arch_pack xfs_dir2_sf_off_t; |
| |
| /* |
| * Offset in data space of a data entry. |
| */ |
| typedef __uint32_t xfs_dir2_dataptr_t; |
| #define XFS_DIR2_MAX_DATAPTR ((xfs_dir2_dataptr_t)0xffffffff) |
| #define XFS_DIR2_NULL_DATAPTR ((xfs_dir2_dataptr_t)0) |
| |
| /* |
| * Byte offset in a directory. |
| */ |
| typedef xfs_off_t xfs_dir2_off_t; |
| |
| /* |
| * Directory block number (logical dirblk in file) |
| */ |
| typedef __uint32_t xfs_dir2_db_t; |
| |
| /* |
| * Inode number stored as 8 8-bit values. |
| */ |
| typedef struct { __uint8_t i[8]; } xfs_dir2_ino8_t; |
| |
| /* |
| * Inode number stored as 4 8-bit values. |
| * Works a lot of the time, when all the inode numbers in a directory |
| * fit in 32 bits. |
| */ |
| typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t; |
| |
| typedef union { |
| xfs_dir2_ino8_t i8; |
| xfs_dir2_ino4_t i4; |
| } xfs_dir2_inou_t; |
| #define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL) |
| |
| /* |
| * Directory layout when stored internal to an inode. |
| * |
| * Small directories are packed as tightly as possible so as to fit into the |
| * literal area of the inode. These "shortform" directories consist of a |
| * single xfs_dir2_sf_hdr header followed by zero or more xfs_dir2_sf_entry |
| * structures. Due the different inode number storage size and the variable |
| * length name field in the xfs_dir2_sf_entry all these structure are |
| * variable length, and the accessors in this file should be used to iterate |
| * over them. |
| */ |
| typedef struct xfs_dir2_sf_hdr { |
| __uint8_t count; /* count of entries */ |
| __uint8_t i8count; /* count of 8-byte inode #s */ |
| xfs_dir2_inou_t parent; /* parent dir inode number */ |
| } __arch_pack xfs_dir2_sf_hdr_t; |
| |
| typedef struct xfs_dir2_sf_entry { |
| __u8 namelen; /* actual name length */ |
| xfs_dir2_sf_off_t offset; /* saved offset */ |
| __u8 name[]; /* name, variable size */ |
| /* |
| * A single byte containing the file type field follows the inode |
| * number for version 3 directory entries. |
| * |
| * A xfs_dir2_ino8_t or xfs_dir2_ino4_t follows here, at a |
| * variable offset after the name. |
| */ |
| } __arch_pack xfs_dir2_sf_entry_t; |
| |
| static inline int xfs_dir2_sf_hdr_size(int i8count) |
| { |
| return sizeof(struct xfs_dir2_sf_hdr) - |
| (i8count == 0) * |
| (sizeof(xfs_dir2_ino8_t) - sizeof(xfs_dir2_ino4_t)); |
| } |
| |
| static inline xfs_dir2_data_aoff_t |
| xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep) |
| { |
| return get_unaligned_be16(&sfep->offset.i); |
| } |
| |
| static inline void |
| xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off) |
| { |
| put_unaligned_be16(off, &sfep->offset.i); |
| } |
| |
| static inline struct xfs_dir2_sf_entry * |
| xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr) |
| { |
| return (struct xfs_dir2_sf_entry *) |
| ((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count)); |
| } |
| |
| /* |
| * Data block structures. |
| * |
| * A pure data block looks like the following drawing on disk: |
| * |
| * +-------------------------------------------------+ |
| * | xfs_dir2_data_hdr_t | |
| * +-------------------------------------------------+ |
| * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| * | ... | |
| * +-------------------------------------------------+ |
| * | unused space | |
| * +-------------------------------------------------+ |
| * |
| * As all the entries are variable size structures the accessors below should |
| * be used to iterate over them. |
| * |
| * In addition to the pure data blocks for the data and node formats, |
| * most structures are also used for the combined data/freespace "block" |
| * format below. |
| */ |
| |
| #define XFS_DIR2_DATA_ALIGN_LOG 3 /* i.e., 8 bytes */ |
| #define XFS_DIR2_DATA_ALIGN (1 << XFS_DIR2_DATA_ALIGN_LOG) |
| #define XFS_DIR2_DATA_FREE_TAG 0xffff |
| #define XFS_DIR2_DATA_FD_COUNT 3 |
| |
| /* |
| * Directory address space divided into sections, |
| * spaces separated by 32GB. |
| */ |
| #define XFS_DIR2_SPACE_SIZE (1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG)) |
| #define XFS_DIR2_DATA_SPACE 0 |
| #define XFS_DIR2_DATA_OFFSET (XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE) |
| |
| /* |
| * Describe a free area in the data block. |
| * |
| * The freespace will be formatted as a xfs_dir2_data_unused_t. |
| */ |
| typedef struct xfs_dir2_data_free { |
| __be16 offset; /* start of freespace */ |
| __be16 length; /* length of freespace */ |
| } xfs_dir2_data_free_t; |
| |
| /* |
| * Header for the data blocks. |
| * |
| * The code knows that XFS_DIR2_DATA_FD_COUNT is 3. |
| */ |
| typedef struct xfs_dir2_data_hdr { |
| __be32 magic; /* XFS_DIR2_DATA_MAGIC or */ |
| /* XFS_DIR2_BLOCK_MAGIC */ |
| xfs_dir2_data_free_t bestfree[XFS_DIR2_DATA_FD_COUNT]; |
| } xfs_dir2_data_hdr_t; |
| |
| /* |
| * define a structure for all the verification fields we are adding to the |
| * directory block structures. This will be used in several structures. |
| * The magic number must be the first entry to align with all the dir2 |
| * structures so we determine how to decode them just by the magic number. |
| */ |
| struct xfs_dir3_blk_hdr { |
| __be32 magic; /* magic number */ |
| __be32 crc; /* CRC of block */ |
| __be64 blkno; /* first block of the buffer */ |
| __be64 lsn; /* sequence number of last write */ |
| uuid_t uuid; /* filesystem we belong to */ |
| __be64 owner; /* inode that owns the block */ |
| }; |
| |
| struct xfs_dir3_data_hdr { |
| struct xfs_dir3_blk_hdr hdr; |
| xfs_dir2_data_free_t best_free[XFS_DIR2_DATA_FD_COUNT]; |
| __be32 pad; /* 64 bit alignment */ |
| }; |
| |
| #define XFS_DIR3_DATA_CRC_OFF offsetof(struct xfs_dir3_data_hdr, hdr.crc) |
| |
| /* |
| * Active entry in a data block. |
| * |
| * Aligned to 8 bytes. After the variable length name field there is a |
| * 2 byte tag field, which can be accessed using xfs_dir3_data_entry_tag_p. |
| * |
| * For dir3 structures, there is file type field between the name and the tag. |
| * This can only be manipulated by helper functions. It is packed hard against |
| * the end of the name so any padding for rounding is between the file type and |
| * the tag. |
| */ |
| typedef struct xfs_dir2_data_entry { |
| __be64 inumber; /* inode number */ |
| __u8 namelen; /* name length */ |
| __u8 name[]; /* name bytes, no null */ |
| /* __u8 filetype; */ /* type of inode we point to */ |
| /* __be16 tag; */ /* starting offset of us */ |
| } xfs_dir2_data_entry_t; |
| |
| /* |
| * Unused entry in a data block. |
| * |
| * Aligned to 8 bytes. Tag appears as the last 2 bytes and must be accessed |
| * using xfs_dir2_data_unused_tag_p. |
| */ |
| typedef struct xfs_dir2_data_unused { |
| __be16 freetag; /* XFS_DIR2_DATA_FREE_TAG */ |
| __be16 length; /* total free length */ |
| /* variable offset */ |
| __be16 tag; /* starting offset of us */ |
| } xfs_dir2_data_unused_t; |
| |
| /* |
| * Pointer to a freespace's tag word. |
| */ |
| static inline __be16 * |
| xfs_dir2_data_unused_tag_p(struct xfs_dir2_data_unused *dup) |
| { |
| return (__be16 *)((char *)dup + |
| be16_to_cpu(dup->length) - sizeof(__be16)); |
| } |
| |
| /* |
| * Leaf block structures. |
| * |
| * A pure leaf block looks like the following drawing on disk: |
| * |
| * +---------------------------+ |
| * | xfs_dir2_leaf_hdr_t | |
| * +---------------------------+ |
| * | xfs_dir2_leaf_entry_t | |
| * | xfs_dir2_leaf_entry_t | |
| * | xfs_dir2_leaf_entry_t | |
| * | xfs_dir2_leaf_entry_t | |
| * | ... | |
| * +---------------------------+ |
| * | xfs_dir2_data_off_t | |
| * | xfs_dir2_data_off_t | |
| * | xfs_dir2_data_off_t | |
| * | ... | |
| * +---------------------------+ |
| * | xfs_dir2_leaf_tail_t | |
| * +---------------------------+ |
| * |
| * The xfs_dir2_data_off_t members (bests) and tail are at the end of the block |
| * for single-leaf (magic = XFS_DIR2_LEAF1_MAGIC) blocks only, but not present |
| * for directories with separate leaf nodes and free space blocks |
| * (magic = XFS_DIR2_LEAFN_MAGIC). |
| * |
| * As all the entries are variable size structures the accessors below should |
| * be used to iterate over them. |
| */ |
| |
| /* |
| * Offset of the leaf/node space. First block in this space |
| * is the btree root. |
| */ |
| #define XFS_DIR2_LEAF_SPACE 1 |
| #define XFS_DIR2_LEAF_OFFSET (XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE) |
| |
| /* |
| * Leaf block header. |
| */ |
| typedef struct xfs_dir2_leaf_hdr { |
| xfs_da_blkinfo_t info; /* header for da routines */ |
| __be16 count; /* count of entries */ |
| __be16 stale; /* count of stale entries */ |
| } xfs_dir2_leaf_hdr_t; |
| |
| struct xfs_dir3_leaf_hdr { |
| struct xfs_da3_blkinfo info; /* header for da routines */ |
| __be16 count; /* count of entries */ |
| __be16 stale; /* count of stale entries */ |
| __be32 pad; /* 64 bit alignment */ |
| }; |
| |
| struct xfs_dir3_icleaf_hdr { |
| __uint32_t forw; |
| __uint32_t back; |
| __uint16_t magic; |
| __uint16_t count; |
| __uint16_t stale; |
| }; |
| |
| /* |
| * Leaf block entry. |
| */ |
| typedef struct xfs_dir2_leaf_entry { |
| __be32 hashval; /* hash value of name */ |
| __be32 address; /* address of data entry */ |
| } xfs_dir2_leaf_entry_t; |
| |
| /* |
| * Leaf block tail. |
| */ |
| typedef struct xfs_dir2_leaf_tail { |
| __be32 bestcount; |
| } xfs_dir2_leaf_tail_t; |
| |
| /* |
| * Leaf block. |
| */ |
| typedef struct xfs_dir2_leaf { |
| xfs_dir2_leaf_hdr_t hdr; /* leaf header */ |
| xfs_dir2_leaf_entry_t __ents[]; /* entries */ |
| } xfs_dir2_leaf_t; |
| |
| struct xfs_dir3_leaf { |
| struct xfs_dir3_leaf_hdr hdr; /* leaf header */ |
| struct xfs_dir2_leaf_entry __ents[]; /* entries */ |
| }; |
| |
| #define XFS_DIR3_LEAF_CRC_OFF offsetof(struct xfs_dir3_leaf_hdr, info.crc) |
| |
| /* |
| * Get address of the bests array in the single-leaf block. |
| */ |
| static inline __be16 * |
| xfs_dir2_leaf_bests_p(struct xfs_dir2_leaf_tail *ltp) |
| { |
| return (__be16 *)ltp - be32_to_cpu(ltp->bestcount); |
| } |
| |
| /* |
| * Free space block defintions for the node format. |
| */ |
| |
| /* |
| * Offset of the freespace index. |
| */ |
| #define XFS_DIR2_FREE_SPACE 2 |
| #define XFS_DIR2_FREE_OFFSET (XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE) |
| |
| typedef struct xfs_dir2_free_hdr { |
| __be32 magic; /* XFS_DIR2_FREE_MAGIC */ |
| __be32 firstdb; /* db of first entry */ |
| __be32 nvalid; /* count of valid entries */ |
| __be32 nused; /* count of used entries */ |
| } xfs_dir2_free_hdr_t; |
| |
| typedef struct xfs_dir2_free { |
| xfs_dir2_free_hdr_t hdr; /* block header */ |
| __be16 bests[]; /* best free counts */ |
| /* unused entries are -1 */ |
| } xfs_dir2_free_t; |
| |
| struct xfs_dir3_free_hdr { |
| struct xfs_dir3_blk_hdr hdr; |
| __be32 firstdb; /* db of first entry */ |
| __be32 nvalid; /* count of valid entries */ |
| __be32 nused; /* count of used entries */ |
| __be32 pad; /* 64 bit alignment */ |
| }; |
| |
| struct xfs_dir3_free { |
| struct xfs_dir3_free_hdr hdr; |
| __be16 bests[]; /* best free counts */ |
| /* unused entries are -1 */ |
| }; |
| |
| #define XFS_DIR3_FREE_CRC_OFF offsetof(struct xfs_dir3_free, hdr.hdr.crc) |
| |
| /* |
| * In core version of the free block header, abstracted away from on-disk format |
| * differences. Use this in the code, and convert to/from the disk version using |
| * xfs_dir3_free_hdr_from_disk/xfs_dir3_free_hdr_to_disk. |
| */ |
| struct xfs_dir3_icfree_hdr { |
| __uint32_t magic; |
| __uint32_t firstdb; |
| __uint32_t nvalid; |
| __uint32_t nused; |
| |
| }; |
| |
| /* |
| * Single block format. |
| * |
| * The single block format looks like the following drawing on disk: |
| * |
| * +-------------------------------------------------+ |
| * | xfs_dir2_data_hdr_t | |
| * +-------------------------------------------------+ |
| * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t : |
| * | ... | |
| * +-------------------------------------------------+ |
| * | unused space | |
| * +-------------------------------------------------+ |
| * | ... | |
| * | xfs_dir2_leaf_entry_t | |
| * | xfs_dir2_leaf_entry_t | |
| * +-------------------------------------------------+ |
| * | xfs_dir2_block_tail_t | |
| * +-------------------------------------------------+ |
| * |
| * As all the entries are variable size structures the accessors below should |
| * be used to iterate over them. |
| */ |
| |
| typedef struct xfs_dir2_block_tail { |
| __be32 count; /* count of leaf entries */ |
| __be32 stale; /* count of stale lf entries */ |
| } xfs_dir2_block_tail_t; |
| |
| /* |
| * Pointer to the leaf entries embedded in a data block (1-block format) |
| */ |
| static inline struct xfs_dir2_leaf_entry * |
| xfs_dir2_block_leaf_p(struct xfs_dir2_block_tail *btp) |
| { |
| return ((struct xfs_dir2_leaf_entry *)btp) - be32_to_cpu(btp->count); |
| } |
| |
| |
| /* |
| * Attribute storage layout |
| * |
| * Attribute lists are structured around Btrees where all the data |
| * elements are in the leaf nodes. Attribute names are hashed into an int, |
| * then that int is used as the index into the Btree. Since the hashval |
| * of an attribute name may not be unique, we may have duplicate keys. The |
| * internal links in the Btree are logical block offsets into the file. |
| * |
| * Struct leaf_entry's are packed from the top. Name/values grow from the |
| * bottom but are not packed. The freemap contains run-length-encoded entries |
| * for the free bytes after the leaf_entry's, but only the N largest such, |
| * smaller runs are dropped. When the freemap doesn't show enough space |
| * for an allocation, we compact the name/value area and try again. If we |
| * still don't have enough space, then we have to split the block. The |
| * name/value structs (both local and remote versions) must be 32bit aligned. |
| * |
| * Since we have duplicate hash keys, for each key that matches, compare |
| * the actual name string. The root and intermediate node search always |
| * takes the first-in-the-block key match found, so we should only have |
| * to work "forw"ard. If none matches, continue with the "forw"ard leaf |
| * nodes until the hash key changes or the attribute name is found. |
| * |
| * We store the fact that an attribute is a ROOT/USER/SECURE attribute in |
| * the leaf_entry. The namespaces are independent only because we also look |
| * at the namespace bit when we are looking for a matching attribute name. |
| * |
| * We also store an "incomplete" bit in the leaf_entry. It shows that an |
| * attribute is in the middle of being created and should not be shown to |
| * the user if we crash during the time that the bit is set. We clear the |
| * bit when we have finished setting up the attribute. We do this because |
| * we cannot create some large attributes inside a single transaction, and we |
| * need some indication that we weren't finished if we crash in the middle. |
| */ |
| #define XFS_ATTR_LEAF_MAPSIZE 3 /* how many freespace slots */ |
| |
| /* |
| * Entries are packed toward the top as tight as possible. |
| */ |
| typedef struct xfs_attr_shortform { |
| struct xfs_attr_sf_hdr { /* constant-structure header block */ |
| __be16 totsize; /* total bytes in shortform list */ |
| __u8 count; /* count of active entries */ |
| } hdr; |
| struct xfs_attr_sf_entry { |
| __uint8_t namelen; /* actual length of name (no NULL) */ |
| __uint8_t valuelen; /* actual length of value (no NULL) */ |
| __uint8_t flags; /* flags bits (see xfs_attr_leaf.h) */ |
| __uint8_t nameval[1]; /* name & value bytes concatenated */ |
| } list[1]; /* variable sized array */ |
| } xfs_attr_shortform_t; |
| |
| typedef struct xfs_attr_leaf_map { /* RLE map of free bytes */ |
| __be16 base; /* base of free region */ |
| __be16 size; /* length of free region */ |
| } xfs_attr_leaf_map_t; |
| |
| typedef struct xfs_attr_leaf_hdr { /* constant-structure header block */ |
| xfs_da_blkinfo_t info; /* block type, links, etc. */ |
| __be16 count; /* count of active leaf_entry's */ |
| __be16 usedbytes; /* num bytes of names/values stored */ |
| __be16 firstused; /* first used byte in name area */ |
| __u8 holes; /* != 0 if blk needs compaction */ |
| __u8 pad1; |
| xfs_attr_leaf_map_t freemap[XFS_ATTR_LEAF_MAPSIZE]; |
| /* N largest free regions */ |
| } xfs_attr_leaf_hdr_t; |
| |
| typedef struct xfs_attr_leaf_entry { /* sorted on key, not name */ |
| __be32 hashval; /* hash value of name */ |
| __be16 nameidx; /* index into buffer of name/value */ |
| __u8 flags; /* LOCAL/ROOT/SECURE/INCOMPLETE flag */ |
| __u8 pad2; /* unused pad byte */ |
| } xfs_attr_leaf_entry_t; |
| |
| typedef struct xfs_attr_leaf_name_local { |
| __be16 valuelen; /* number of bytes in value */ |
| __u8 namelen; /* length of name bytes */ |
| __u8 nameval[1]; /* name/value bytes */ |
| } xfs_attr_leaf_name_local_t; |
| |
| typedef struct xfs_attr_leaf_name_remote { |
| __be32 valueblk; /* block number of value bytes */ |
| __be32 valuelen; /* number of bytes in value */ |
| __u8 namelen; /* length of name bytes */ |
| __u8 name[1]; /* name bytes */ |
| } xfs_attr_leaf_name_remote_t; |
| |
| typedef struct xfs_attr_leafblock { |
| xfs_attr_leaf_hdr_t hdr; /* constant-structure header block */ |
| xfs_attr_leaf_entry_t entries[1]; /* sorted on key, not name */ |
| /* |
| * The rest of the block contains the following structures after the |
| * leaf entries, growing from the bottom up. The variables are never |
| * referenced and definining them can actually make gcc optimize away |
| * accesses to the 'entries' array above index 0 so don't do that. |
| * |
| * xfs_attr_leaf_name_local_t namelist; |
| * xfs_attr_leaf_name_remote_t valuelist; |
| */ |
| } xfs_attr_leafblock_t; |
| |
| /* |
| * CRC enabled leaf structures. Called "version 3" structures to match the |
| * version number of the directory and dablk structures for this feature, and |
| * attr2 is already taken by the variable inode attribute fork size feature. |
| */ |
| struct xfs_attr3_leaf_hdr { |
| struct xfs_da3_blkinfo info; |
| __be16 count; |
| __be16 usedbytes; |
| __be16 firstused; |
| __u8 holes; |
| __u8 pad1; |
| struct xfs_attr_leaf_map freemap[XFS_ATTR_LEAF_MAPSIZE]; |
| __be32 pad2; /* 64 bit alignment */ |
| }; |
| |
| #define XFS_ATTR3_LEAF_CRC_OFF (offsetof(struct xfs_attr3_leaf_hdr, info.crc)) |
| |
| struct xfs_attr3_leafblock { |
| struct xfs_attr3_leaf_hdr hdr; |
| struct xfs_attr_leaf_entry entries[1]; |
| |
| /* |
| * The rest of the block contains the following structures after the |
| * leaf entries, growing from the bottom up. The variables are never |
| * referenced, the locations accessed purely from helper functions. |
| * |
| * struct xfs_attr_leaf_name_local |
| * struct xfs_attr_leaf_name_remote |
| */ |
| }; |
| |
| /* |
| * incore, neutral version of the attribute leaf header |
| */ |
| struct xfs_attr3_icleaf_hdr { |
| __uint32_t forw; |
| __uint32_t back; |
| __uint16_t magic; |
| __uint16_t count; |
| __uint16_t usedbytes; |
| /* |
| * firstused is 32-bit here instead of 16-bit like the on-disk variant |
| * to support maximum fsb size of 64k without overflow issues throughout |
| * the attr code. Instead, the overflow condition is handled on |
| * conversion to/from disk. |
| */ |
| __uint32_t firstused; |
| __u8 holes; |
| struct { |
| __uint16_t base; |
| __uint16_t size; |
| } freemap[XFS_ATTR_LEAF_MAPSIZE]; |
| }; |
| |
| /* |
| * Special value to represent fs block size in the leaf header firstused field. |
| * Only used when block size overflows the 2-bytes available on disk. |
| */ |
| #define XFS_ATTR3_LEAF_NULLOFF 0 |
| |
| /* |
| * Flags used in the leaf_entry[i].flags field. |
| * NOTE: the INCOMPLETE bit must not collide with the flags bits specified |
| * on the system call, they are "or"ed together for various operations. |
| */ |
| #define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */ |
| #define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */ |
| #define XFS_ATTR_SECURE_BIT 2 /* limit access to secure attrs */ |
| #define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */ |
| #define XFS_ATTR_LOCAL (1 << XFS_ATTR_LOCAL_BIT) |
| #define XFS_ATTR_ROOT (1 << XFS_ATTR_ROOT_BIT) |
| #define XFS_ATTR_SECURE (1 << XFS_ATTR_SECURE_BIT) |
| #define XFS_ATTR_INCOMPLETE (1 << XFS_ATTR_INCOMPLETE_BIT) |
| |
| /* |
| * Conversion macros for converting namespace bits from argument flags |
| * to ondisk flags. |
| */ |
| #define XFS_ATTR_NSP_ARGS_MASK (ATTR_ROOT | ATTR_SECURE) |
| #define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE) |
| #define XFS_ATTR_NSP_ONDISK(flags) ((flags) & XFS_ATTR_NSP_ONDISK_MASK) |
| #define XFS_ATTR_NSP_ARGS(flags) ((flags) & XFS_ATTR_NSP_ARGS_MASK) |
| #define XFS_ATTR_NSP_ARGS_TO_ONDISK(x) (((x) & ATTR_ROOT ? XFS_ATTR_ROOT : 0) |\ |
| ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0)) |
| #define XFS_ATTR_NSP_ONDISK_TO_ARGS(x) (((x) & XFS_ATTR_ROOT ? ATTR_ROOT : 0) |\ |
| ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0)) |
| |
| /* |
| * Alignment for namelist and valuelist entries (since they are mixed |
| * there can be only one alignment value) |
| */ |
| #define XFS_ATTR_LEAF_NAME_ALIGN ((uint)sizeof(xfs_dablk_t)) |
| |
| static inline int |
| xfs_attr3_leaf_hdr_size(struct xfs_attr_leafblock *leafp) |
| { |
| if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) |
| return sizeof(struct xfs_attr3_leaf_hdr); |
| return sizeof(struct xfs_attr_leaf_hdr); |
| } |
| |
| static inline struct xfs_attr_leaf_entry * |
| xfs_attr3_leaf_entryp(xfs_attr_leafblock_t *leafp) |
| { |
| if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) |
| return &((struct xfs_attr3_leafblock *)leafp)->entries[0]; |
| return &leafp->entries[0]; |
| } |
| |
| /* |
| * Cast typed pointers for "local" and "remote" name/value structs. |
| */ |
| static inline char * |
| xfs_attr3_leaf_name(xfs_attr_leafblock_t *leafp, int idx) |
| { |
| struct xfs_attr_leaf_entry *entries = xfs_attr3_leaf_entryp(leafp); |
| |
| return &((char *)leafp)[be16_to_cpu(entries[idx].nameidx)]; |
| } |
| |
| static inline xfs_attr_leaf_name_remote_t * |
| xfs_attr3_leaf_name_remote(xfs_attr_leafblock_t *leafp, int idx) |
| { |
| return (xfs_attr_leaf_name_remote_t *)xfs_attr3_leaf_name(leafp, idx); |
| } |
| |
| static inline xfs_attr_leaf_name_local_t * |
| xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx) |
| { |
| return (xfs_attr_leaf_name_local_t *)xfs_attr3_leaf_name(leafp, idx); |
| } |
| |
| /* |
| * Calculate total bytes used (including trailing pad for alignment) for |
| * a "local" name/value structure, a "remote" name/value structure, and |
| * a pointer which might be either. |
| */ |
| static inline int xfs_attr_leaf_entsize_remote(int nlen) |
| { |
| return ((uint)sizeof(xfs_attr_leaf_name_remote_t) - 1 + (nlen) + \ |
| XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); |
| } |
| |
| static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen) |
| { |
| return ((uint)sizeof(xfs_attr_leaf_name_local_t) - 1 + (nlen) + (vlen) + |
| XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); |
| } |
| |
| static inline int xfs_attr_leaf_entsize_local_max(int bsize) |
| { |
| return (((bsize) >> 1) + ((bsize) >> 2)); |
| } |
| |
| |
| |
| /* |
| * Remote attribute block format definition |
| * |
| * There is one of these headers per filesystem block in a remote attribute. |
| * This is done to ensure there is a 1:1 mapping between the attribute value |
| * length and the number of blocks needed to store the attribute. This makes the |
| * verification of a buffer a little more complex, but greatly simplifies the |
| * allocation, reading and writing of these attributes as we don't have to guess |
| * the number of blocks needed to store the attribute data. |
| */ |
| #define XFS_ATTR3_RMT_MAGIC 0x5841524d /* XARM */ |
| |
| struct xfs_attr3_rmt_hdr { |
| __be32 rm_magic; |
| __be32 rm_offset; |
| __be32 rm_bytes; |
| __be32 rm_crc; |
| uuid_t rm_uuid; |
| __be64 rm_owner; |
| __be64 rm_blkno; |
| __be64 rm_lsn; |
| }; |
| |
| #define XFS_ATTR3_RMT_CRC_OFF offsetof(struct xfs_attr3_rmt_hdr, rm_crc) |
| |
| #define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize) \ |
| ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \ |
| sizeof(struct xfs_attr3_rmt_hdr) : 0)) |
| |
| #endif /* __XFS_DA_FORMAT_H__ */ |