1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * GRUB -- GRand Unified Bootloader
4 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
7 * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
10 #ifndef _SYS_ZAP_IMPL_H
11 #define _SYS_ZAP_IMPL_H
13 #define ZAP_MAGIC 0x2F52AB2ABULL
15 #define ZAP_HASHBITS 28
16 #define MZAP_ENT_LEN 64
17 #define MZAP_NAME_LEN (MZAP_ENT_LEN - 8 - 4 - 2)
18 #define MZAP_MAX_BLKSHIFT SPA_MAXBLOCKSHIFT
19 #define MZAP_MAX_BLKSZ (1 << MZAP_MAX_BLKSHIFT)
21 typedef struct mzap_ent_phys {
24 uint16_t mze_pad; /* in case we want to chain them someday */
25 char mze_name[MZAP_NAME_LEN];
28 typedef struct mzap_phys {
29 uint64_t mz_block_type; /* ZBT_MICRO */
32 mzap_ent_phys_t mz_chunk[1];
33 /* actually variable size depending on block size */
37 * The (fat) zap is stored in one object. It is an array of
38 * 1<<FZAP_BLOCK_SHIFT byte blocks. The layout looks like one of:
40 * ptrtbl fits in first block:
41 * [zap_phys_t zap_ptrtbl_shift < 6] [zap_leaf_t] ...
43 * ptrtbl too big for first block:
44 * [zap_phys_t zap_ptrtbl_shift >= 6] [zap_leaf_t] [ptrtbl] ...
48 #define ZBT_LEAF ((1ULL << 63) + 0)
49 #define ZBT_HEADER ((1ULL << 63) + 1)
50 #define ZBT_MICRO ((1ULL << 63) + 3)
51 /* any other values are ptrtbl blocks */
54 * the embedded pointer table takes up half a block:
55 * block size / entry size (2^3) / 2
57 #define ZAP_EMBEDDED_PTRTBL_SHIFT(zap) (FZAP_BLOCK_SHIFT(zap) - 3 - 1)
60 * The embedded pointer table starts half-way through the block. Since
61 * the pointer table itself is half the block, it starts at (64-bit)
62 * word number (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)).
64 #define ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) \
65 ((uint64_t *)(zap)->zap_f.zap_phys) \
66 [(idx) + (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap))]
70 * If zap_phys_t is modified, zap_byteswap() must be modified.
72 typedef struct zap_phys {
73 uint64_t zap_block_type; /* ZBT_HEADER */
74 uint64_t zap_magic; /* ZAP_MAGIC */
76 struct zap_table_phys {
77 uint64_t zt_blk; /* starting block number */
78 uint64_t zt_numblks; /* number of blocks */
79 uint64_t zt_shift; /* bits to index it */
80 uint64_t zt_nextblk; /* next (larger) copy start block */
81 uint64_t zt_blks_copied; /* number source blocks copied */
84 uint64_t zap_freeblk; /* the next free block */
85 uint64_t zap_num_leafs; /* number of leafs */
86 uint64_t zap_num_entries; /* number of entries */
87 uint64_t zap_salt; /* salt to stir into hash function */
88 uint64_t zap_normflags; /* flags for u8_textprep_str() */
89 uint64_t zap_flags; /* zap_flag_t */
91 * This structure is followed by padding, and then the embedded
92 * pointer table. The embedded pointer table takes up second
93 * half of the block. It is accessed using the
94 * ZAP_EMBEDDED_PTRTBL_ENT() macro.
98 #endif /* _SYS_ZAP_IMPL_H */