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805 lines
27 KiB
805 lines
27 KiB
/* SPDX-License-Identifier: GPL-2.0 */ |
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/* |
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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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#ifndef __XFS_DA_FORMAT_H__ |
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#define __XFS_DA_FORMAT_H__ |
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|
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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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/* |
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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: v3 dirlf single blks */ |
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#define XFS_DIR3_LEAFN_MAGIC 0x3dff /* magic number: v3 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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* 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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* 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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#define XFS_INO32_SIZE 4 |
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#define XFS_INO64_SIZE 8 |
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#define XFS_INO64_DIFF (XFS_INO64_SIZE - XFS_INO32_SIZE) |
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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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uint8_t parent[8]; /* parent dir inode number */ |
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} __packed 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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__u8 offset[2]; /* 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 64-bit or 32-bit inode number follows here, at a variable offset |
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* after the name. |
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*/ |
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} __packed 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) * XFS_INO64_DIFF; |
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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); |
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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); |
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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_MAX_SPACES 3 |
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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 */ |
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__be16 count; /* count of entries */ |
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__be16 stale; /* count of stale entries */ |
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} xfs_dir2_leaf_hdr_t; |
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struct xfs_dir3_leaf_hdr { |
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struct xfs_da3_blkinfo info; /* header for da routines */ |
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__be16 count; /* count of entries */ |
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__be16 stale; /* count of stale entries */ |
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__be32 pad; /* 64 bit alignment */ |
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}; |
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/* |
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* Leaf block entry. |
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*/ |
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typedef struct xfs_dir2_leaf_entry { |
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__be32 hashval; /* hash value of name */ |
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__be32 address; /* address of data entry */ |
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} xfs_dir2_leaf_entry_t; |
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/* |
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* Leaf block tail. |
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*/ |
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typedef struct xfs_dir2_leaf_tail { |
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__be32 bestcount; |
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} xfs_dir2_leaf_tail_t; |
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/* |
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* Leaf block. |
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*/ |
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typedef struct xfs_dir2_leaf { |
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xfs_dir2_leaf_hdr_t hdr; /* leaf header */ |
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xfs_dir2_leaf_entry_t __ents[]; /* entries */ |
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} xfs_dir2_leaf_t; |
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struct xfs_dir3_leaf { |
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struct xfs_dir3_leaf_hdr hdr; /* leaf header */ |
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struct xfs_dir2_leaf_entry __ents[]; /* entries */ |
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}; |
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#define XFS_DIR3_LEAF_CRC_OFF offsetof(struct xfs_dir3_leaf_hdr, info.crc) |
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/* |
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* Get address of the bests array in the single-leaf block. |
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*/ |
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static inline __be16 * |
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xfs_dir2_leaf_bests_p(struct xfs_dir2_leaf_tail *ltp) |
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{ |
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return (__be16 *)ltp - be32_to_cpu(ltp->bestcount); |
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} |
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/* |
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* Free space block definitions for the node format. |
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*/ |
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/* |
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* Offset of the freespace index. |
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*/ |
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#define XFS_DIR2_FREE_SPACE 2 |
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#define XFS_DIR2_FREE_OFFSET (XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE) |
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typedef struct xfs_dir2_free_hdr { |
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__be32 magic; /* XFS_DIR2_FREE_MAGIC */ |
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__be32 firstdb; /* db of first entry */ |
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__be32 nvalid; /* count of valid entries */ |
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__be32 nused; /* count of used entries */ |
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} xfs_dir2_free_hdr_t; |
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typedef struct xfs_dir2_free { |
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xfs_dir2_free_hdr_t hdr; /* block header */ |
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__be16 bests[]; /* best free counts */ |
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/* unused entries are -1 */ |
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} xfs_dir2_free_t; |
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struct xfs_dir3_free_hdr { |
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struct xfs_dir3_blk_hdr hdr; |
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__be32 firstdb; /* db of first entry */ |
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__be32 nvalid; /* count of valid entries */ |
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__be32 nused; /* count of used entries */ |
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__be32 pad; /* 64 bit alignment */ |
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}; |
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struct xfs_dir3_free { |
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struct xfs_dir3_free_hdr hdr; |
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__be16 bests[]; /* best free counts */ |
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/* unused entries are -1 */ |
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}; |
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#define XFS_DIR3_FREE_CRC_OFF offsetof(struct xfs_dir3_free, hdr.hdr.crc) |
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|
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/* |
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* Single block format. |
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* |
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* The single block format 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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* | ... | |
|
* +-------------------------------------------------+ |
|
* | 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 * |
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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 |
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* |
|
* Attribute lists are structured around Btrees where all the data |
|
* elements are in the leaf nodes. Attribute names are hashed into an int, |
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* 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 |
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* 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. |
|
*/ |
|
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 */ |
|
__u8 padding; |
|
} 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[]; /* name & value bytes concatenated */ |
|
} list[1]; /* variable sized array */ |
|
}; |
|
|
|
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 |
|
*/ |
|
}; |
|
|
|
/* |
|
* 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. |
|
*/ |
|
#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 (1u << XFS_ATTR_LOCAL_BIT) |
|
#define XFS_ATTR_ROOT (1u << XFS_ATTR_ROOT_BIT) |
|
#define XFS_ATTR_SECURE (1u << XFS_ATTR_SECURE_BIT) |
|
#define XFS_ATTR_INCOMPLETE (1u << XFS_ATTR_INCOMPLETE_BIT) |
|
#define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE) |
|
|
|
/* |
|
* 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 round_up(sizeof(struct xfs_attr_leaf_name_remote) - 1 + |
|
nlen, XFS_ATTR_LEAF_NAME_ALIGN); |
|
} |
|
|
|
static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen) |
|
{ |
|
return round_up(sizeof(struct xfs_attr_leaf_name_local) - 1 + |
|
nlen + vlen, XFS_ATTR_LEAF_NAME_ALIGN); |
|
} |
|
|
|
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_has_crc((mp)) ? \ |
|
sizeof(struct xfs_attr3_rmt_hdr) : 0)) |
|
|
|
/* Number of bytes in a directory block. */ |
|
static inline unsigned int xfs_dir2_dirblock_bytes(struct xfs_sb *sbp) |
|
{ |
|
return 1 << (sbp->sb_blocklog + sbp->sb_dirblklog); |
|
} |
|
|
|
xfs_failaddr_t xfs_da3_blkinfo_verify(struct xfs_buf *bp, |
|
struct xfs_da3_blkinfo *hdr3); |
|
|
|
#endif /* __XFS_DA_FORMAT_H__ */
|
|
|