xref: /openbmc/linux/fs/xfs/xfs_ondisk.h (revision 1a59d1b8)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2016 Oracle.
4  * All Rights Reserved.
5  */
6 #ifndef __XFS_ONDISK_H
7 #define __XFS_ONDISK_H
8 
9 #define XFS_CHECK_STRUCT_SIZE(structname, size) \
10 	BUILD_BUG_ON_MSG(sizeof(structname) != (size), "XFS: sizeof(" \
11 		#structname ") is wrong, expected " #size)
12 
13 #define XFS_CHECK_OFFSET(structname, member, off) \
14 	BUILD_BUG_ON_MSG(offsetof(structname, member) != (off), \
15 		"XFS: offsetof(" #structname ", " #member ") is wrong, " \
16 		"expected " #off)
17 
18 static inline void __init
19 xfs_check_ondisk_structs(void)
20 {
21 	/* ag/file structures */
22 	XFS_CHECK_STRUCT_SIZE(struct xfs_acl,			4);
23 	XFS_CHECK_STRUCT_SIZE(struct xfs_acl_entry,		12);
24 	XFS_CHECK_STRUCT_SIZE(struct xfs_agf,			224);
25 	XFS_CHECK_STRUCT_SIZE(struct xfs_agfl,			36);
26 	XFS_CHECK_STRUCT_SIZE(struct xfs_agi,			336);
27 	XFS_CHECK_STRUCT_SIZE(struct xfs_bmbt_key,		8);
28 	XFS_CHECK_STRUCT_SIZE(struct xfs_bmbt_rec,		16);
29 	XFS_CHECK_STRUCT_SIZE(struct xfs_bmdr_block,		4);
30 	XFS_CHECK_STRUCT_SIZE(struct xfs_btree_block_shdr,	48);
31 	XFS_CHECK_STRUCT_SIZE(struct xfs_btree_block_lhdr,	64);
32 	XFS_CHECK_STRUCT_SIZE(struct xfs_btree_block,		72);
33 	XFS_CHECK_STRUCT_SIZE(struct xfs_dinode,		176);
34 	XFS_CHECK_STRUCT_SIZE(struct xfs_disk_dquot,		104);
35 	XFS_CHECK_STRUCT_SIZE(struct xfs_dqblk,			136);
36 	XFS_CHECK_STRUCT_SIZE(struct xfs_dsb,			264);
37 	XFS_CHECK_STRUCT_SIZE(struct xfs_dsymlink_hdr,		56);
38 	XFS_CHECK_STRUCT_SIZE(struct xfs_inobt_key,		4);
39 	XFS_CHECK_STRUCT_SIZE(struct xfs_inobt_rec,		16);
40 	XFS_CHECK_STRUCT_SIZE(struct xfs_refcount_key,		4);
41 	XFS_CHECK_STRUCT_SIZE(struct xfs_refcount_rec,		12);
42 	XFS_CHECK_STRUCT_SIZE(struct xfs_rmap_key,		20);
43 	XFS_CHECK_STRUCT_SIZE(struct xfs_rmap_rec,		24);
44 	XFS_CHECK_STRUCT_SIZE(struct xfs_timestamp,		8);
45 	XFS_CHECK_STRUCT_SIZE(xfs_alloc_key_t,			8);
46 	XFS_CHECK_STRUCT_SIZE(xfs_alloc_ptr_t,			4);
47 	XFS_CHECK_STRUCT_SIZE(xfs_alloc_rec_t,			8);
48 	XFS_CHECK_STRUCT_SIZE(xfs_inobt_ptr_t,			4);
49 	XFS_CHECK_STRUCT_SIZE(xfs_refcount_ptr_t,		4);
50 	XFS_CHECK_STRUCT_SIZE(xfs_rmap_ptr_t,			4);
51 
52 	/* dir/attr trees */
53 	XFS_CHECK_STRUCT_SIZE(struct xfs_attr3_leaf_hdr,	80);
54 	XFS_CHECK_STRUCT_SIZE(struct xfs_attr3_leafblock,	88);
55 	XFS_CHECK_STRUCT_SIZE(struct xfs_attr3_rmt_hdr,		56);
56 	XFS_CHECK_STRUCT_SIZE(struct xfs_da3_blkinfo,		56);
57 	XFS_CHECK_STRUCT_SIZE(struct xfs_da3_intnode,		64);
58 	XFS_CHECK_STRUCT_SIZE(struct xfs_da3_node_hdr,		64);
59 	XFS_CHECK_STRUCT_SIZE(struct xfs_dir3_blk_hdr,		48);
60 	XFS_CHECK_STRUCT_SIZE(struct xfs_dir3_data_hdr,		64);
61 	XFS_CHECK_STRUCT_SIZE(struct xfs_dir3_free,		64);
62 	XFS_CHECK_STRUCT_SIZE(struct xfs_dir3_free_hdr,		64);
63 	XFS_CHECK_STRUCT_SIZE(struct xfs_dir3_leaf,		64);
64 	XFS_CHECK_STRUCT_SIZE(struct xfs_dir3_leaf_hdr,		64);
65 	XFS_CHECK_STRUCT_SIZE(xfs_attr_leaf_entry_t,		8);
66 	XFS_CHECK_STRUCT_SIZE(xfs_attr_leaf_hdr_t,		32);
67 	XFS_CHECK_STRUCT_SIZE(xfs_attr_leaf_map_t,		4);
68 	XFS_CHECK_STRUCT_SIZE(xfs_attr_leaf_name_local_t,	4);
69 
70 	/*
71 	 * m68k has problems with xfs_attr_leaf_name_remote_t, but we pad it to
72 	 * 4 bytes anyway so it's not obviously a problem.  Hence for the moment
73 	 * we don't check this structure. This can be re-instated when the attr
74 	 * definitions are updated to use c99 VLA definitions.
75 	 *
76 	XFS_CHECK_STRUCT_SIZE(xfs_attr_leaf_name_remote_t,	12);
77 	 */
78 
79 	XFS_CHECK_OFFSET(xfs_attr_leaf_name_local_t, valuelen,	0);
80 	XFS_CHECK_OFFSET(xfs_attr_leaf_name_local_t, namelen,	2);
81 	XFS_CHECK_OFFSET(xfs_attr_leaf_name_local_t, nameval,	3);
82 	XFS_CHECK_OFFSET(xfs_attr_leaf_name_remote_t, valueblk,	0);
83 	XFS_CHECK_OFFSET(xfs_attr_leaf_name_remote_t, valuelen,	4);
84 	XFS_CHECK_OFFSET(xfs_attr_leaf_name_remote_t, namelen,	8);
85 	XFS_CHECK_OFFSET(xfs_attr_leaf_name_remote_t, name,	9);
86 	XFS_CHECK_STRUCT_SIZE(xfs_attr_leafblock_t,		40);
87 	XFS_CHECK_OFFSET(xfs_attr_shortform_t, hdr.totsize,	0);
88 	XFS_CHECK_OFFSET(xfs_attr_shortform_t, hdr.count,	2);
89 	XFS_CHECK_OFFSET(xfs_attr_shortform_t, list[0].namelen,	4);
90 	XFS_CHECK_OFFSET(xfs_attr_shortform_t, list[0].valuelen, 5);
91 	XFS_CHECK_OFFSET(xfs_attr_shortform_t, list[0].flags,	6);
92 	XFS_CHECK_OFFSET(xfs_attr_shortform_t, list[0].nameval,	7);
93 	XFS_CHECK_STRUCT_SIZE(xfs_da_blkinfo_t,			12);
94 	XFS_CHECK_STRUCT_SIZE(xfs_da_intnode_t,			16);
95 	XFS_CHECK_STRUCT_SIZE(xfs_da_node_entry_t,		8);
96 	XFS_CHECK_STRUCT_SIZE(xfs_da_node_hdr_t,		16);
97 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_data_free_t,		4);
98 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_data_hdr_t,		16);
99 	XFS_CHECK_OFFSET(xfs_dir2_data_unused_t, freetag,	0);
100 	XFS_CHECK_OFFSET(xfs_dir2_data_unused_t, length,	2);
101 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_free_hdr_t,		16);
102 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_free_t,			16);
103 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_leaf_entry_t,		8);
104 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_leaf_hdr_t,		16);
105 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_leaf_t,			16);
106 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_leaf_tail_t,		4);
107 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_sf_entry_t,		3);
108 	XFS_CHECK_OFFSET(xfs_dir2_sf_entry_t, namelen,		0);
109 	XFS_CHECK_OFFSET(xfs_dir2_sf_entry_t, offset,		1);
110 	XFS_CHECK_OFFSET(xfs_dir2_sf_entry_t, name,		3);
111 	XFS_CHECK_STRUCT_SIZE(xfs_dir2_sf_hdr_t,		10);
112 
113 	/* log structures */
114 	XFS_CHECK_STRUCT_SIZE(struct xfs_dq_logformat,		24);
115 	XFS_CHECK_STRUCT_SIZE(struct xfs_efd_log_format_32,	28);
116 	XFS_CHECK_STRUCT_SIZE(struct xfs_efd_log_format_64,	32);
117 	XFS_CHECK_STRUCT_SIZE(struct xfs_efi_log_format_32,	28);
118 	XFS_CHECK_STRUCT_SIZE(struct xfs_efi_log_format_64,	32);
119 	XFS_CHECK_STRUCT_SIZE(struct xfs_extent_32,		12);
120 	XFS_CHECK_STRUCT_SIZE(struct xfs_extent_64,		16);
121 	XFS_CHECK_STRUCT_SIZE(struct xfs_log_dinode,		176);
122 	XFS_CHECK_STRUCT_SIZE(struct xfs_icreate_log,		28);
123 	XFS_CHECK_STRUCT_SIZE(struct xfs_ictimestamp,		8);
124 	XFS_CHECK_STRUCT_SIZE(struct xfs_inode_log_format_32,	52);
125 	XFS_CHECK_STRUCT_SIZE(struct xfs_inode_log_format,	56);
126 	XFS_CHECK_STRUCT_SIZE(struct xfs_qoff_logformat,	20);
127 	XFS_CHECK_STRUCT_SIZE(struct xfs_trans_header,		16);
128 
129 	/*
130 	 * The v5 superblock format extended several v4 header structures with
131 	 * additional data. While new fields are only accessible on v5
132 	 * superblocks, it's important that the v5 structures place original v4
133 	 * fields/headers in the correct location on-disk. For example, we must
134 	 * be able to find magic values at the same location in certain blocks
135 	 * regardless of superblock version.
136 	 *
137 	 * The following checks ensure that various v5 data structures place the
138 	 * subset of v4 metadata associated with the same type of block at the
139 	 * start of the on-disk block. If there is no data structure definition
140 	 * for certain types of v4 blocks, traverse down to the first field of
141 	 * common metadata (e.g., magic value) and make sure it is at offset
142 	 * zero.
143 	 */
144 	XFS_CHECK_OFFSET(struct xfs_dir3_leaf, hdr.info.hdr,	0);
145 	XFS_CHECK_OFFSET(struct xfs_da3_intnode, hdr.info.hdr,	0);
146 	XFS_CHECK_OFFSET(struct xfs_dir3_data_hdr, hdr.magic,	0);
147 	XFS_CHECK_OFFSET(struct xfs_dir3_free, hdr.hdr.magic,	0);
148 	XFS_CHECK_OFFSET(struct xfs_attr3_leafblock, hdr.info.hdr, 0);
149 }
150 
151 #endif /* __XFS_ONDISK_H */
152