1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * GRUB -- GRand Unified Bootloader 4 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc. 5 */ 6 /* 7 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 8 * Use is subject to license terms. 9 */ 10 11 #ifndef _SYS_ZAP_LEAF_H 12 #define _SYS_ZAP_LEAF_H 13 14 #define ZAP_LEAF_MAGIC 0x2AB1EAF 15 16 /* chunk size = 24 bytes */ 17 #define ZAP_LEAF_CHUNKSIZE 24 18 19 /* 20 * The amount of space within the chunk available for the array is: 21 * chunk size - space for type (1) - space for next pointer (2) 22 */ 23 #define ZAP_LEAF_ARRAY_BYTES (ZAP_LEAF_CHUNKSIZE - 3) 24 25 typedef enum zap_chunk_type { 26 ZAP_CHUNK_FREE = 253, 27 ZAP_CHUNK_ENTRY = 252, 28 ZAP_CHUNK_ARRAY = 251, 29 ZAP_CHUNK_TYPE_MAX = 250 30 } zap_chunk_type_t; 31 32 /* 33 * TAKE NOTE: 34 * If zap_leaf_phys_t is modified, zap_leaf_byteswap() must be modified. 35 */ 36 typedef struct zap_leaf_phys { 37 struct zap_leaf_header { 38 uint64_t lh_block_type; /* ZBT_LEAF */ 39 uint64_t lh_pad1; 40 uint64_t lh_prefix; /* hash prefix of this leaf */ 41 uint32_t lh_magic; /* ZAP_LEAF_MAGIC */ 42 uint16_t lh_nfree; /* number free chunks */ 43 uint16_t lh_nentries; /* number of entries */ 44 uint16_t lh_prefix_len; /* num bits used to id this */ 45 46 /* above is accessable to zap, below is zap_leaf private */ 47 48 uint16_t lh_freelist; /* chunk head of free list */ 49 uint8_t lh_pad2[12]; 50 } l_hdr; /* 2 24-byte chunks */ 51 52 /* 53 * The header is followed by a hash table with 54 * ZAP_LEAF_HASH_NUMENTRIES(zap) entries. The hash table is 55 * followed by an array of ZAP_LEAF_NUMCHUNKS(zap) 56 * zap_leaf_chunk structures. These structures are accessed 57 * with the ZAP_LEAF_CHUNK() macro. 58 */ 59 60 uint16_t l_hash[1]; 61 } zap_leaf_phys_t; 62 63 typedef union zap_leaf_chunk { 64 struct zap_leaf_entry { 65 uint8_t le_type; /* always ZAP_CHUNK_ENTRY */ 66 uint8_t le_int_size; /* size of ints */ 67 uint16_t le_next; /* next entry in hash chain */ 68 uint16_t le_name_chunk; /* first chunk of the name */ 69 uint16_t le_name_length; /* bytes in name, incl null */ 70 uint16_t le_value_chunk; /* first chunk of the value */ 71 uint16_t le_value_length; /* value length in ints */ 72 uint32_t le_cd; /* collision differentiator */ 73 uint64_t le_hash; /* hash value of the name */ 74 } l_entry; 75 struct zap_leaf_array { 76 uint8_t la_type; /* always ZAP_CHUNK_ARRAY */ 77 union { 78 uint8_t la_array[ZAP_LEAF_ARRAY_BYTES]; 79 uint64_t la_array64; 80 } __attribute__ ((packed)); 81 uint16_t la_next; /* next blk or CHAIN_END */ 82 } l_array; 83 struct zap_leaf_free { 84 uint8_t lf_type; /* always ZAP_CHUNK_FREE */ 85 uint8_t lf_pad[ZAP_LEAF_ARRAY_BYTES]; 86 uint16_t lf_next; /* next in free list, or CHAIN_END */ 87 } l_free; 88 } zap_leaf_chunk_t; 89 90 #endif /* _SYS_ZAP_LEAF_H */ 91