1 /*- 2 * Copyright (c) 2012, 2010 Zheng Liu <lz@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 #ifndef _FS_EXT2FS_EXT2_EXTENTS_H_ 29 #define _FS_EXT2FS_EXT2_EXTENTS_H_ 30 31 #include <sys/types.h> 32 33 #define EXT4_EXT_MAGIC 0xf30a 34 #define EXT4_MAX_BLOCKS 0xffffffff 35 #define EXT_INIT_MAX_LEN (1UL << 15) 36 #define EXT4_MAX_LEN (EXT_INIT_MAX_LEN - 1) 37 #define EXT4_EXT_DEPTH_MAX 5 38 39 #define EXT4_EXT_CACHE_NO 0 40 #define EXT4_EXT_CACHE_GAP 1 41 #define EXT4_EXT_CACHE_IN 2 42 43 /* 44 * Ext4 file system extent on disk. 45 */ 46 struct ext4_extent { 47 uint32_t e_blk; /* first logical block */ 48 uint16_t e_len; /* number of blocks */ 49 uint16_t e_start_hi; /* high 16 bits of physical block */ 50 uint32_t e_start_lo; /* low 32 bits of physical block */ 51 }; 52 53 /* 54 * Extent index on disk. 55 */ 56 struct ext4_extent_index { 57 uint32_t ei_blk; /* indexes logical blocks */ 58 uint32_t ei_leaf_lo; /* points to physical block of the 59 * next level */ 60 uint16_t ei_leaf_hi; /* high 16 bits of physical block */ 61 uint16_t ei_unused; 62 }; 63 64 /* 65 * Extent tree header. 66 */ 67 struct ext4_extent_header { 68 uint16_t eh_magic; /* magic number: 0xf30a */ 69 uint16_t eh_ecount; /* number of valid entries */ 70 uint16_t eh_max; /* capacity of store in entries */ 71 uint16_t eh_depth; /* the depth of extent tree */ 72 uint32_t eh_gen; /* generation of extent tree */ 73 }; 74 75 /* 76 * Save cached extent. 77 */ 78 struct ext4_extent_cache { 79 daddr_t ec_start; /* extent start */ 80 uint32_t ec_blk; /* logical block */ 81 uint32_t ec_len; 82 uint32_t ec_type; 83 }; 84 85 /* 86 * Save path to some extent. 87 */ 88 struct ext4_extent_path { 89 int index_count; 90 uint16_t ep_depth; 91 uint64_t ep_blk; 92 char *ep_data; 93 struct ext4_extent *ep_ext; 94 struct ext4_extent_index *ep_index; 95 struct ext4_extent_header *ep_header; 96 }; 97 98 #define EXT_FIRST_EXTENT(hdr) ((struct ext4_extent *)(((char *)(hdr)) + \ 99 sizeof(struct ext4_extent_header))) 100 #define EXT_FIRST_INDEX(hdr) ((struct ext4_extent_index *)(((char *)(hdr)) + \ 101 sizeof(struct ext4_extent_header))) 102 #define EXT_LAST_EXTENT(hdr) (EXT_FIRST_EXTENT((hdr)) + (hdr)->eh_ecount - 1) 103 #define EXT_LAST_INDEX(hdr) (EXT_FIRST_INDEX((hdr)) + (hdr)->eh_ecount - 1) 104 #define EXT4_EXTENT_TAIL_OFFSET(hdr) (sizeof(struct ext4_extent_header) + \ 105 (sizeof(struct ext4_extent) * (hdr)->eh_max)) 106 #define EXT_HAS_FREE_INDEX(path) \ 107 ((path)->ep_header->eh_ecount < (path)->ep_header->eh_max) 108 #define EXT_MAX_EXTENT(hdr) (EXT_FIRST_EXTENT(hdr) + ((hdr)->eh_max) - 1) 109 #define EXT_MAX_INDEX(hdr) (EXT_FIRST_INDEX((hdr)) + (hdr)->eh_max - 1) 110 111 struct inode; 112 struct m_ext2fs; 113 void ext4_ext_tree_init(struct inode *ip); 114 int ext4_ext_in_cache(struct inode *, daddr_t, struct ext4_extent *); 115 void ext4_ext_put_cache(struct inode *, struct ext4_extent *, int); 116 int ext4_ext_find_extent(struct inode *, daddr_t, struct ext4_extent_path **); 117 void ext4_ext_path_free(struct ext4_extent_path *path); 118 int ext4_ext_remove_space(struct inode *ip, off_t length, int flags, 119 struct ucred *cred, struct thread *td); 120 int ext4_ext_get_blocks(struct inode *ip, int64_t iblock, 121 unsigned long max_blocks, struct ucred *cred, struct buf **bpp, int *allocate, uint32_t *); 122 #ifdef EXT2FS_DEBUG 123 void ext4_ext_print_extent_tree_status(struct inode * ip); 124 #endif 125 126 #endif /* !_FS_EXT2FS_EXT2_EXTENTS_H_ */ 127