1 /* 2 * GRUB -- GRand Unified Bootloader 3 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 /* 8 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 9 * Use is subject to license terms. 10 */ 11 12 #ifndef _SYS_ZAP_LEAF_H 13 #define _SYS_ZAP_LEAF_H 14 15 #define ZAP_LEAF_MAGIC 0x2AB1EAF 16 17 /* chunk size = 24 bytes */ 18 #define ZAP_LEAF_CHUNKSIZE 24 19 20 /* 21 * The amount of space within the chunk available for the array is: 22 * chunk size - space for type (1) - space for next pointer (2) 23 */ 24 #define ZAP_LEAF_ARRAY_BYTES (ZAP_LEAF_CHUNKSIZE - 3) 25 26 typedef enum zap_chunk_type { 27 ZAP_CHUNK_FREE = 253, 28 ZAP_CHUNK_ENTRY = 252, 29 ZAP_CHUNK_ARRAY = 251, 30 ZAP_CHUNK_TYPE_MAX = 250 31 } zap_chunk_type_t; 32 33 /* 34 * TAKE NOTE: 35 * If zap_leaf_phys_t is modified, zap_leaf_byteswap() must be modified. 36 */ 37 typedef struct zap_leaf_phys { 38 struct zap_leaf_header { 39 uint64_t lh_block_type; /* ZBT_LEAF */ 40 uint64_t lh_pad1; 41 uint64_t lh_prefix; /* hash prefix of this leaf */ 42 uint32_t lh_magic; /* ZAP_LEAF_MAGIC */ 43 uint16_t lh_nfree; /* number free chunks */ 44 uint16_t lh_nentries; /* number of entries */ 45 uint16_t lh_prefix_len; /* num bits used to id this */ 46 47 /* above is accessable to zap, below is zap_leaf private */ 48 49 uint16_t lh_freelist; /* chunk head of free list */ 50 uint8_t lh_pad2[12]; 51 } l_hdr; /* 2 24-byte chunks */ 52 53 /* 54 * The header is followed by a hash table with 55 * ZAP_LEAF_HASH_NUMENTRIES(zap) entries. The hash table is 56 * followed by an array of ZAP_LEAF_NUMCHUNKS(zap) 57 * zap_leaf_chunk structures. These structures are accessed 58 * with the ZAP_LEAF_CHUNK() macro. 59 */ 60 61 uint16_t l_hash[1]; 62 } zap_leaf_phys_t; 63 64 typedef union zap_leaf_chunk { 65 struct zap_leaf_entry { 66 uint8_t le_type; /* always ZAP_CHUNK_ENTRY */ 67 uint8_t le_int_size; /* size of ints */ 68 uint16_t le_next; /* next entry in hash chain */ 69 uint16_t le_name_chunk; /* first chunk of the name */ 70 uint16_t le_name_length; /* bytes in name, incl null */ 71 uint16_t le_value_chunk; /* first chunk of the value */ 72 uint16_t le_value_length; /* value length in ints */ 73 uint32_t le_cd; /* collision differentiator */ 74 uint64_t le_hash; /* hash value of the name */ 75 } l_entry; 76 struct zap_leaf_array { 77 uint8_t la_type; /* always ZAP_CHUNK_ARRAY */ 78 union { 79 uint8_t la_array[ZAP_LEAF_ARRAY_BYTES]; 80 uint64_t la_array64; 81 } __attribute__ ((packed)); 82 uint16_t la_next; /* next blk or CHAIN_END */ 83 } l_array; 84 struct zap_leaf_free { 85 uint8_t lf_type; /* always ZAP_CHUNK_FREE */ 86 uint8_t lf_pad[ZAP_LEAF_ARRAY_BYTES]; 87 uint16_t lf_next; /* next in free list, or CHAIN_END */ 88 } l_free; 89 } zap_leaf_chunk_t; 90 91 #endif /* _SYS_ZAP_LEAF_H */ 92