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873 lines
29 KiB
873 lines
29 KiB
/*
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* Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
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* Copyright (c) 2013 Red Hat, Inc.
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* All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it would be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#ifndef __XFS_DA_FORMAT_H__
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#define __XFS_DA_FORMAT_H__
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/*
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* This structure is common to both leaf nodes and non-leaf nodes in the Btree.
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*
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* It is used to manage a doubly linked list of all blocks at the same
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* level in the Btree, and to identify which type of block this is.
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*/
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#define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */
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#define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */
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#define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */
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#define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */
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typedef struct xfs_da_blkinfo {
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__be32 forw; /* previous block in list */
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__be32 back; /* following block in list */
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__be16 magic; /* validity check on block */
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__be16 pad; /* unused */
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} xfs_da_blkinfo_t;
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/*
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* CRC enabled directory structure types
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*
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* The headers change size for the additional verification information, but
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* otherwise the tree layouts and contents are unchanged. Hence the da btree
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* code can use the struct xfs_da_blkinfo for manipulating the tree links and
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* magic numbers without modification for both v2 and v3 nodes.
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*/
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#define XFS_DA3_NODE_MAGIC 0x3ebe /* magic number: non-leaf blocks */
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#define XFS_ATTR3_LEAF_MAGIC 0x3bee /* magic number: attribute leaf blks */
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#define XFS_DIR3_LEAF1_MAGIC 0x3df1 /* magic number: v2 dirlf single blks */
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#define XFS_DIR3_LEAFN_MAGIC 0x3dff /* magic number: v2 dirlf multi blks */
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struct xfs_da3_blkinfo {
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/*
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* the node link manipulation code relies on the fact that the first
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* element of this structure is the struct xfs_da_blkinfo so it can
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* ignore the differences in the rest of the structures.
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*/
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struct xfs_da_blkinfo hdr;
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__be32 crc; /* CRC of block */
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__be64 blkno; /* first block of the buffer */
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__be64 lsn; /* sequence number of last write */
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uuid_t uuid; /* filesystem we belong to */
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__be64 owner; /* inode that owns the block */
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};
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/*
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* This is the structure of the root and intermediate nodes in the Btree.
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* The leaf nodes are defined above.
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*
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* Entries are not packed.
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*
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* Since we have duplicate keys, use a binary search but always follow
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* all match in the block, not just the first match found.
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*/
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#define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */
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typedef struct xfs_da_node_hdr {
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struct xfs_da_blkinfo info; /* block type, links, etc. */
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__be16 __count; /* count of active entries */
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__be16 __level; /* level above leaves (leaf == 0) */
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} xfs_da_node_hdr_t;
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struct xfs_da3_node_hdr {
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struct xfs_da3_blkinfo info; /* block type, links, etc. */
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__be16 __count; /* count of active entries */
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__be16 __level; /* level above leaves (leaf == 0) */
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__be32 __pad32;
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};
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#define XFS_DA3_NODE_CRC_OFF (offsetof(struct xfs_da3_node_hdr, info.crc))
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typedef struct xfs_da_node_entry {
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__be32 hashval; /* hash value for this descendant */
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__be32 before; /* Btree block before this key */
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} xfs_da_node_entry_t;
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typedef struct xfs_da_intnode {
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struct xfs_da_node_hdr hdr;
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struct xfs_da_node_entry __btree[];
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} xfs_da_intnode_t;
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struct xfs_da3_intnode {
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struct xfs_da3_node_hdr hdr;
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struct xfs_da_node_entry __btree[];
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};
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/*
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* In-core version of the node header to abstract the differences in the v2 and
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* v3 disk format of the headers. Callers need to convert to/from disk format as
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* appropriate.
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*/
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struct xfs_da3_icnode_hdr {
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__uint32_t forw;
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__uint32_t back;
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__uint16_t magic;
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__uint16_t count;
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__uint16_t level;
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};
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/*
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* Directory version 2.
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*
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* There are 4 possible formats:
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* - shortform - embedded into the inode
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* - single block - data with embedded leaf at the end
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* - multiple data blocks, single leaf+freeindex block
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* - data blocks, node and leaf blocks (btree), freeindex blocks
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*
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* Note: many node blocks structures and constants are shared with the attr
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* code and defined in xfs_da_btree.h.
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*/
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#define XFS_DIR2_BLOCK_MAGIC 0x58443242 /* XD2B: single block dirs */
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#define XFS_DIR2_DATA_MAGIC 0x58443244 /* XD2D: multiblock dirs */
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#define XFS_DIR2_FREE_MAGIC 0x58443246 /* XD2F: free index blocks */
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/*
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* Directory Version 3 With CRCs.
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*
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* The tree formats are the same as for version 2 directories. The difference
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* is in the block header and dirent formats. In many cases the v3 structures
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* use v2 definitions as they are no different and this makes code sharing much
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* easier.
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*
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* Also, the xfs_dir3_*() functions handle both v2 and v3 formats - if the
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* format is v2 then they switch to the existing v2 code, or the format is v3
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* they implement the v3 functionality. This means the existing dir2 is a mix of
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* xfs_dir2/xfs_dir3 calls and functions. The xfs_dir3 functions are called
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* where there is a difference in the formats, otherwise the code is unchanged.
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*
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* Where it is possible, the code decides what to do based on the magic numbers
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* in the blocks rather than feature bits in the superblock. This means the code
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* is as independent of the external XFS code as possible as doesn't require
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* passing struct xfs_mount pointers into places where it isn't really
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* necessary.
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*
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* Version 3 includes:
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*
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* - a larger block header for CRC and identification purposes and so the
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* offsets of all the structures inside the blocks are different.
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*
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* - new magic numbers to be able to detect the v2/v3 types on the fly.
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*/
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#define XFS_DIR3_BLOCK_MAGIC 0x58444233 /* XDB3: single block dirs */
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#define XFS_DIR3_DATA_MAGIC 0x58444433 /* XDD3: multiblock dirs */
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#define XFS_DIR3_FREE_MAGIC 0x58444633 /* XDF3: free index blocks */
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/*
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* Dirents in version 3 directories have a file type field. Additions to this
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* list are an on-disk format change, requiring feature bits. Valid values
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* are as follows:
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*/
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#define XFS_DIR3_FT_UNKNOWN 0
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#define XFS_DIR3_FT_REG_FILE 1
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#define XFS_DIR3_FT_DIR 2
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#define XFS_DIR3_FT_CHRDEV 3
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#define XFS_DIR3_FT_BLKDEV 4
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#define XFS_DIR3_FT_FIFO 5
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#define XFS_DIR3_FT_SOCK 6
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#define XFS_DIR3_FT_SYMLINK 7
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#define XFS_DIR3_FT_WHT 8
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#define XFS_DIR3_FT_MAX 9
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/*
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* Byte offset in data block and shortform entry.
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*/
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typedef __uint16_t xfs_dir2_data_off_t;
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#define NULLDATAOFF 0xffffU
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typedef uint xfs_dir2_data_aoff_t; /* argument form */
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/*
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* Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t.
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* Only need 16 bits, this is the byte offset into the single block form.
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*/
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typedef struct { __uint8_t i[2]; } __arch_pack xfs_dir2_sf_off_t;
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/*
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* Offset in data space of a data entry.
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*/
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typedef __uint32_t xfs_dir2_dataptr_t;
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#define XFS_DIR2_MAX_DATAPTR ((xfs_dir2_dataptr_t)0xffffffff)
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#define XFS_DIR2_NULL_DATAPTR ((xfs_dir2_dataptr_t)0)
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/*
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* Byte offset in a directory.
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*/
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typedef xfs_off_t xfs_dir2_off_t;
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/*
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* Directory block number (logical dirblk in file)
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*/
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typedef __uint32_t xfs_dir2_db_t;
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/*
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* Inode number stored as 8 8-bit values.
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*/
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typedef struct { __uint8_t i[8]; } xfs_dir2_ino8_t;
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/*
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* Inode number stored as 4 8-bit values.
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* Works a lot of the time, when all the inode numbers in a directory
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* fit in 32 bits.
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*/
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typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t;
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typedef union {
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xfs_dir2_ino8_t i8;
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xfs_dir2_ino4_t i4;
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} xfs_dir2_inou_t;
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#define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL)
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/*
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* Directory layout when stored internal to an inode.
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*
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* Small directories are packed as tightly as possible so as to fit into the
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* literal area of the inode. These "shortform" directories consist of a
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* single xfs_dir2_sf_hdr header followed by zero or more xfs_dir2_sf_entry
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* structures. Due the different inode number storage size and the variable
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* length name field in the xfs_dir2_sf_entry all these structure are
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* variable length, and the accessors in this file should be used to iterate
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* over them.
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*/
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typedef struct xfs_dir2_sf_hdr {
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__uint8_t count; /* count of entries */
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__uint8_t i8count; /* count of 8-byte inode #s */
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xfs_dir2_inou_t parent; /* parent dir inode number */
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} __arch_pack xfs_dir2_sf_hdr_t;
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typedef struct xfs_dir2_sf_entry {
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__u8 namelen; /* actual name length */
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xfs_dir2_sf_off_t offset; /* saved offset */
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__u8 name[]; /* name, variable size */
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/*
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* A single byte containing the file type field follows the inode
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* number for version 3 directory entries.
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*
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* A xfs_dir2_ino8_t or xfs_dir2_ino4_t follows here, at a
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* variable offset after the name.
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*/
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} __arch_pack xfs_dir2_sf_entry_t;
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static inline int xfs_dir2_sf_hdr_size(int i8count)
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{
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return sizeof(struct xfs_dir2_sf_hdr) -
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(i8count == 0) *
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(sizeof(xfs_dir2_ino8_t) - sizeof(xfs_dir2_ino4_t));
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}
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static inline xfs_dir2_data_aoff_t
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xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep)
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{
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return get_unaligned_be16(&sfep->offset.i);
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}
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static inline void
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xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off)
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{
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put_unaligned_be16(off, &sfep->offset.i);
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}
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static inline struct xfs_dir2_sf_entry *
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xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr)
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{
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return (struct xfs_dir2_sf_entry *)
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((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count));
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}
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/*
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* Data block structures.
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*
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* A pure data block looks like the following drawing on disk:
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*
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* +-------------------------------------------------+
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* | xfs_dir2_data_hdr_t |
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* +-------------------------------------------------+
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* | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
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* | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
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* | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
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* | ... |
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* +-------------------------------------------------+
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* | unused space |
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* +-------------------------------------------------+
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*
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* As all the entries are variable size structures the accessors below should
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* be used to iterate over them.
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*
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* In addition to the pure data blocks for the data and node formats,
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* most structures are also used for the combined data/freespace "block"
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* format below.
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*/
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#define XFS_DIR2_DATA_ALIGN_LOG 3 /* i.e., 8 bytes */
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#define XFS_DIR2_DATA_ALIGN (1 << XFS_DIR2_DATA_ALIGN_LOG)
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#define XFS_DIR2_DATA_FREE_TAG 0xffff
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#define XFS_DIR2_DATA_FD_COUNT 3
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/*
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* Directory address space divided into sections,
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* spaces separated by 32GB.
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*/
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#define XFS_DIR2_SPACE_SIZE (1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG))
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#define XFS_DIR2_DATA_SPACE 0
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#define XFS_DIR2_DATA_OFFSET (XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE)
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/*
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* Describe a free area in the data block.
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*
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* The freespace will be formatted as a xfs_dir2_data_unused_t.
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*/
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typedef struct xfs_dir2_data_free {
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__be16 offset; /* start of freespace */
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__be16 length; /* length of freespace */
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} xfs_dir2_data_free_t;
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/*
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* Header for the data blocks.
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*
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* The code knows that XFS_DIR2_DATA_FD_COUNT is 3.
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*/
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typedef struct xfs_dir2_data_hdr {
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__be32 magic; /* XFS_DIR2_DATA_MAGIC or */
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/* XFS_DIR2_BLOCK_MAGIC */
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xfs_dir2_data_free_t bestfree[XFS_DIR2_DATA_FD_COUNT];
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} xfs_dir2_data_hdr_t;
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/*
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* define a structure for all the verification fields we are adding to the
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* directory block structures. This will be used in several structures.
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* The magic number must be the first entry to align with all the dir2
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* structures so we determine how to decode them just by the magic number.
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*/
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struct xfs_dir3_blk_hdr {
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__be32 magic; /* magic number */
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__be32 crc; /* CRC of block */
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__be64 blkno; /* first block of the buffer */
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__be64 lsn; /* sequence number of last write */
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uuid_t uuid; /* filesystem we belong to */
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__be64 owner; /* inode that owns the block */
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};
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struct xfs_dir3_data_hdr {
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struct xfs_dir3_blk_hdr hdr;
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xfs_dir2_data_free_t best_free[XFS_DIR2_DATA_FD_COUNT];
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__be32 pad; /* 64 bit alignment */
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};
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#define XFS_DIR3_DATA_CRC_OFF offsetof(struct xfs_dir3_data_hdr, hdr.crc)
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/*
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* Active entry in a data block.
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*
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* Aligned to 8 bytes. After the variable length name field there is a
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* 2 byte tag field, which can be accessed using xfs_dir3_data_entry_tag_p.
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*
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* For dir3 structures, there is file type field between the name and the tag.
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* This can only be manipulated by helper functions. It is packed hard against
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* the end of the name so any padding for rounding is between the file type and
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* the tag.
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*/
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typedef struct xfs_dir2_data_entry {
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__be64 inumber; /* inode number */
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__u8 namelen; /* name length */
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__u8 name[]; /* name bytes, no null */
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/* __u8 filetype; */ /* type of inode we point to */
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/* __be16 tag; */ /* starting offset of us */
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} xfs_dir2_data_entry_t;
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/*
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* Unused entry in a data block.
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*
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* Aligned to 8 bytes. Tag appears as the last 2 bytes and must be accessed
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* using xfs_dir2_data_unused_tag_p.
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*/
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typedef struct xfs_dir2_data_unused {
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__be16 freetag; /* XFS_DIR2_DATA_FREE_TAG */
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__be16 length; /* total free length */
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/* variable offset */
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__be16 tag; /* starting offset of us */
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} xfs_dir2_data_unused_t;
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/*
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* Pointer to a freespace's tag word.
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*/
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static inline __be16 *
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xfs_dir2_data_unused_tag_p(struct xfs_dir2_data_unused *dup)
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{
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return (__be16 *)((char *)dup +
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be16_to_cpu(dup->length) - sizeof(__be16));
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}
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/*
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* Leaf block structures.
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*
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* A pure leaf block looks like the following drawing on disk:
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*
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* +---------------------------+
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* | xfs_dir2_leaf_hdr_t |
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* +---------------------------+
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* | xfs_dir2_leaf_entry_t |
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* | xfs_dir2_leaf_entry_t |
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* | xfs_dir2_leaf_entry_t |
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* | xfs_dir2_leaf_entry_t |
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* | ... |
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* +---------------------------+
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* | xfs_dir2_data_off_t |
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* | xfs_dir2_data_off_t |
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* | xfs_dir2_data_off_t |
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* | ... |
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* +---------------------------+
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* | xfs_dir2_leaf_tail_t |
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* +---------------------------+
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*
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* The xfs_dir2_data_off_t members (bests) and tail are at the end of the block
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* for single-leaf (magic = XFS_DIR2_LEAF1_MAGIC) blocks only, but not present
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* for directories with separate leaf nodes and free space blocks
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* (magic = XFS_DIR2_LEAFN_MAGIC).
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*
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* As all the entries are variable size structures the accessors below should
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* be used to iterate over them.
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*/
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/*
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* Offset of the leaf/node space. First block in this space
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* is the btree root.
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*/
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#define XFS_DIR2_LEAF_SPACE 1
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#define XFS_DIR2_LEAF_OFFSET (XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE)
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/*
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* Leaf block header.
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*/
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typedef struct xfs_dir2_leaf_hdr {
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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 */
|
|
|
|
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 */
|
|
xfs_attr_leaf_name_local_t namelist; /* grows from bottom of buf */
|
|
xfs_attr_leaf_name_remote_t valuelist; /* grows from bottom of buf */
|
|
} 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__ */
|
|
|