1 /*- 2 * Copyright (c) 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: head/sys/fs/ext2fs/ext2_extents.c 254260 2013-08-12 21:34:48Z pfg $ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/kernel.h> 32 #include <sys/malloc.h> 33 #include <sys/vnode.h> 34 #include <sys/mount.h> 35 #include <sys/buf.h> 36 37 #include <ufs/ufs/quota.h> 38 #include <ufs/ufs/ufsmount.h> 39 #include <ufs/ufs/inode.h> 40 #include <ufs/ext2fs/ext2fs.h> 41 #include <ufs/ext2fs/ext2fs_extents.h> 42 #include <ufs/ext2fs/ext2fs_extern.h> 43 44 static void ext4_ext_binsearch_index(struct inode *ip, struct ext4_extent_path 45 *path, daddr_t lbn) 46 { 47 struct ext4_extent_header *ehp = path->ep_header; 48 struct ext4_extent_index *l, *r, *m; 49 50 l = (struct ext4_extent_index *)(char *)(ehp + 1); 51 r = (struct ext4_extent_index *)(char *)(ehp + 1) + ehp->eh_ecount - 1; 52 while (l <= r) { 53 m = l + (r - l) / 2; 54 if (lbn < m->ei_blk) 55 r = m - 1; 56 else 57 l = m + 1; 58 } 59 60 path->ep_index = l - 1; 61 } 62 63 static void 64 ext4_ext_binsearch(struct inode *ip, struct ext4_extent_path *path, daddr_t lbn) 65 { 66 struct ext4_extent_header *ehp = path->ep_header; 67 struct ext4_extent *l, *r, *m; 68 69 if (ehp->eh_ecount == 0) 70 return; 71 72 l = (struct ext4_extent *)(char *)(ehp + 1); 73 r = (struct ext4_extent *)(char *)(ehp + 1) + ehp->eh_ecount - 1; 74 while (l <= r) { 75 m = l + (r - l) / 2; 76 if (lbn < m->e_blk) 77 r = m - 1; 78 else 79 l = m + 1; 80 } 81 82 path->ep_ext = l - 1; 83 } 84 85 /* 86 * Find a block in ext4 extent cache. 87 */ 88 int 89 ext4_ext_in_cache(struct inode *ip, daddr_t lbn, struct ext4_extent *ep) 90 { 91 struct ext4_extent_cache *ecp; 92 int ret = EXT4_EXT_CACHE_NO; 93 94 ecp = &ip->i_e2fs_ext_cache; 95 96 /* cache is invalid */ 97 if (ecp->ec_type == EXT4_EXT_CACHE_NO) 98 return (ret); 99 100 if (lbn >= ecp->ec_blk && lbn < ecp->ec_blk + ecp->ec_len) { 101 ep->e_blk = ecp->ec_blk; 102 ep->e_start_lo = ecp->ec_start & 0xffffffff; 103 ep->e_start_hi = ecp->ec_start >> 32 & 0xffff; 104 ep->e_len = ecp->ec_len; 105 ret = ecp->ec_type; 106 } 107 return (ret); 108 } 109 110 /* 111 * Put an ext4_extent structure in ext4 cache. 112 */ 113 void 114 ext4_ext_put_cache(struct inode *ip, struct ext4_extent *ep, int type) 115 { 116 struct ext4_extent_cache *ecp; 117 118 ecp = &ip->i_e2fs_ext_cache; 119 ecp->ec_type = type; 120 ecp->ec_blk = ep->e_blk; 121 ecp->ec_len = ep->e_len; 122 ecp->ec_start = (daddr_t)ep->e_start_hi << 32 | ep->e_start_lo; 123 } 124 125 /* 126 * Find an extent. 127 */ 128 struct ext4_extent_path * 129 ext4_ext_find_extent(struct m_ext2fs *fs, struct inode *ip, 130 daddr_t lbn, struct ext4_extent_path *path) 131 { 132 struct vnode *vp; 133 struct ext4_extent_header *ehp; 134 uint16_t i; 135 int error; 136 daddr_t nblk; 137 138 vp = ITOV(ip); 139 ehp = (struct ext4_extent_header *)(char *)ip->i_e2fs_blocks; 140 141 if (ehp->eh_magic != EXT4_EXT_MAGIC) 142 return (NULL); 143 144 path->ep_header = ehp; 145 146 for (i = ehp->eh_depth; i != 0; --i) { 147 ext4_ext_binsearch_index(ip, path, lbn); 148 path->ep_depth = 0; 149 path->ep_ext = NULL; 150 151 nblk = (daddr_t)path->ep_index->ei_leaf_hi << 32 | 152 path->ep_index->ei_leaf_lo; 153 if (path->ep_bp != NULL) { 154 brelse(path->ep_bp); 155 path->ep_bp = NULL; 156 } 157 error = bread(ip->i_devvp, fsbtodb(fs, nblk), fs->e2fs_fsize, 158 &path->ep_bp); 159 if (error) { 160 brelse(path->ep_bp); 161 path->ep_bp = NULL; 162 return (NULL); 163 } 164 ehp = (struct ext4_extent_header *)path->ep_bp->b_data; 165 path->ep_header = ehp; 166 } 167 168 path->ep_depth = i; 169 path->ep_ext = NULL; 170 path->ep_index = NULL; 171 172 ext4_ext_binsearch(ip, path, lbn); 173 return (path); 174 } 175