1139778Simp/*- 21541Srgrimes * Copyright (c) 1989, 1991, 1993 31541Srgrimes * The Regents of the University of California. All rights reserved. 41541Srgrimes * (c) UNIX System Laboratories, Inc. 51541Srgrimes * All or some portions of this file are derived from material licensed 61541Srgrimes * to the University of California by American Telephone and Telegraph 71541Srgrimes * Co. or Unix System Laboratories, Inc. and are reproduced herein with 81541Srgrimes * the permission of UNIX System Laboratories, Inc. 91541Srgrimes * 101541Srgrimes * Redistribution and use in source and binary forms, with or without 111541Srgrimes * modification, are permitted provided that the following conditions 121541Srgrimes * are met: 131541Srgrimes * 1. Redistributions of source code must retain the above copyright 141541Srgrimes * notice, this list of conditions and the following disclaimer. 151541Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 161541Srgrimes * notice, this list of conditions and the following disclaimer in the 171541Srgrimes * documentation and/or other materials provided with the distribution. 181541Srgrimes * 4. Neither the name of the University nor the names of its contributors 191541Srgrimes * may be used to endorse or promote products derived from this software 201541Srgrimes * without specific prior written permission. 211541Srgrimes * 221541Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 231541Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 241541Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 251541Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 261541Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 271541Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 281541Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 291541Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 301541Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 311541Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 321541Srgrimes * SUCH DAMAGE. 331541Srgrimes * 3422521Sdyson * @(#)ufs_bmap.c 8.7 (Berkeley) 3/21/95 3550477Speter * $FreeBSD: stable/10/sys/fs/ext2fs/ext2_bmap.c 317532 2017-04-27 23:14:01Z pfg $ 361541Srgrimes */ 371541Srgrimes 381541Srgrimes#include <sys/param.h> 397430Sbde#include <sys/systm.h> 4060041Sphk#include <sys/bio.h> 411541Srgrimes#include <sys/buf.h> 421541Srgrimes#include <sys/proc.h> 431541Srgrimes#include <sys/vnode.h> 441541Srgrimes#include <sys/mount.h> 451541Srgrimes#include <sys/resourcevar.h> 4662976Smckusick#include <sys/stat.h> 471541Srgrimes 48202283Slulf#include <fs/ext2fs/inode.h> 49254260Spfg#include <fs/ext2fs/fs.h> 50202283Slulf#include <fs/ext2fs/ext2fs.h> 51254260Spfg#include <fs/ext2fs/ext2_dinode.h> 52251344Spfg#include <fs/ext2fs/ext2_extern.h> 53202283Slulf#include <fs/ext2fs/ext2_mount.h> 541541Srgrimes 55254260Spfgstatic int ext4_bmapext(struct vnode *, int32_t, int64_t *, int *, int *); 56254260Spfg 571541Srgrimes/* 58202283Slulf * Bmap converts the logical block number of a file to its physical block 591541Srgrimes * number on the disk. The conversion is done by using the logical block 601541Srgrimes * number to index into the array of block pointers described by the dinode. 611541Srgrimes */ 621541Srgrimesint 63246634Spfgext2_bmap(struct vop_bmap_args *ap) 641541Srgrimes{ 65254283Spfg daddr_t blkno; 6692363Smckusick int error; 6792363Smckusick 681541Srgrimes /* 691541Srgrimes * Check for underlying vnode requests and ensure that logical 701541Srgrimes * to physical mapping is requested. 711541Srgrimes */ 72137726Sphk if (ap->a_bop != NULL) 73137726Sphk *ap->a_bop = &VTOI(ap->a_vp)->i_devvp->v_bufobj; 741541Srgrimes if (ap->a_bnp == NULL) 751541Srgrimes return (0); 761541Srgrimes 77261311Spfg if (VTOI(ap->a_vp)->i_flag & IN_E4EXTENTS) 78254260Spfg error = ext4_bmapext(ap->a_vp, ap->a_bn, &blkno, 79254260Spfg ap->a_runp, ap->a_runb); 80254260Spfg else 81254260Spfg error = ext2_bmaparray(ap->a_vp, ap->a_bn, &blkno, 82254260Spfg ap->a_runp, ap->a_runb); 8392363Smckusick *ap->a_bnp = blkno; 8492363Smckusick return (error); 851541Srgrimes} 861541Srgrimes 871541Srgrimes/* 88254260Spfg * This function converts the logical block number of a file to 89254260Spfg * its physical block number on the disk within ext4 extents. 90254260Spfg */ 91254260Spfgstatic int 92254260Spfgext4_bmapext(struct vnode *vp, int32_t bn, int64_t *bnp, int *runp, int *runb) 93254260Spfg{ 94254260Spfg struct inode *ip; 95254260Spfg struct m_ext2fs *fs; 96254260Spfg struct ext4_extent *ep; 97311232Spfg struct ext4_extent_path path = {.ep_bp = NULL}; 98254260Spfg daddr_t lbn; 99293646Spfg int ret = 0; 100254260Spfg 101254260Spfg ip = VTOI(vp); 102254260Spfg fs = ip->i_e2fs; 103254260Spfg lbn = bn; 104254260Spfg 105317532Spfg /* 106317532Spfg * TODO: need to implement read ahead to improve the performance. 107317532Spfg */ 108254260Spfg if (runp != NULL) 109254260Spfg *runp = 0; 110254260Spfg 111254260Spfg if (runb != NULL) 112254260Spfg *runb = 0; 113254260Spfg 114254260Spfg ext4_ext_find_extent(fs, ip, lbn, &path); 115317532Spfg ep = path.ep_ext; 116317532Spfg if (ep == NULL) 117317532Spfg ret = EIO; 118317532Spfg else { 119317532Spfg *bnp = fsbtodb(fs, lbn - ep->e_blk + 120317532Spfg (ep->e_start_lo | (daddr_t)ep->e_start_hi << 32)); 121254260Spfg 122317532Spfg if (*bnp == 0) 123317532Spfg *bnp = -1; 124293646Spfg } 125254260Spfg 126293646Spfg if (path.ep_bp != NULL) { 127293646Spfg brelse(path.ep_bp); 128293646Spfg path.ep_bp = NULL; 129293646Spfg } 130254260Spfg 131293646Spfg return (ret); 132254260Spfg} 133254260Spfg 134254260Spfg/* 1351541Srgrimes * Indirect blocks are now on the vnode for the file. They are given negative 1361541Srgrimes * logical block numbers. Indirect blocks are addressed by the negative 1371541Srgrimes * address of the first data block to which they point. Double indirect blocks 1381541Srgrimes * are addressed by one less than the address of the first indirect block to 1391541Srgrimes * which they point. Triple indirect blocks are addressed by one less than 1401541Srgrimes * the address of the first double indirect block to which they point. 1411541Srgrimes * 142202283Slulf * ext2_bmaparray does the bmap conversion, and if requested returns the 1431541Srgrimes * array of logical blocks which must be traversed to get to a block. 1441541Srgrimes * Each entry contains the offset into that block that gets you to the 1451541Srgrimes * next block and the disk address of the block (if it is assigned). 1461541Srgrimes */ 1471541Srgrimes 1481541Srgrimesint 149254283Spfgext2_bmaparray(struct vnode *vp, daddr_t bn, daddr_t *bnp, int *runp, int *runb) 1501541Srgrimes{ 15196506Sphk struct inode *ip; 1521541Srgrimes struct buf *bp; 15396596Siedowse struct ext2mount *ump; 1541541Srgrimes struct mount *mp; 155311232Spfg struct indir a[NIADDR + 1], *ap; 156252103Spfg daddr_t daddr; 157252103Spfg e2fs_lbn_t metalbn; 158137039Sphk int error, num, maxrun = 0, bsize; 15976128Sphk int *nump; 1601541Srgrimes 16176128Sphk ap = NULL; 1621541Srgrimes ip = VTOI(vp); 1631541Srgrimes mp = vp->v_mount; 16496596Siedowse ump = VFSTOEXT2(mp); 1651541Srgrimes 166137039Sphk bsize = EXT2_BLOCK_SIZE(ump->um_e2fs); 167137039Sphk 1681541Srgrimes if (runp) { 169137039Sphk maxrun = mp->mnt_iosize_max / bsize - 1; 17032724Sdyson *runp = 0; 17132724Sdyson } 172311232Spfg if (runb) 17332724Sdyson *runb = 0; 17432724Sdyson 17532724Sdyson 17676128Sphk ap = a; 17776128Sphk nump = # 17896596Siedowse error = ext2_getlbns(vp, bn, ap, nump); 1793427Sphk if (error) 1801541Srgrimes return (error); 1811541Srgrimes 1821541Srgrimes num = *nump; 1831541Srgrimes if (num == 0) { 1841541Srgrimes *bnp = blkptrtodb(ump, ip->i_db[bn]); 18596596Siedowse if (*bnp == 0) { 18663788Smckusick *bnp = -1; 18762976Smckusick } else if (runp) { 188254283Spfg daddr_t bnb = bn; 189311232Spfg 1901541Srgrimes for (++bn; bn < NDADDR && *runp < maxrun && 1911541Srgrimes is_sequential(ump, ip->i_db[bn - 1], ip->i_db[bn]); 1921541Srgrimes ++bn, ++*runp); 19310551Sdyson bn = bnb; 19410551Sdyson if (runb && (bn > 0)) { 19510551Sdyson for (--bn; (bn >= 0) && (*runb < maxrun) && 19610551Sdyson is_sequential(ump, ip->i_db[bn], 197254283Spfg ip->i_db[bn + 1]); 19810551Sdyson --bn, ++*runb); 19910551Sdyson } 20010551Sdyson } 2011541Srgrimes return (0); 2021541Srgrimes } 2031541Srgrimes 2041541Srgrimes /* Get disk address out of indirect block array */ 20576128Sphk daddr = ip->i_ib[ap->in_off]; 2061541Srgrimes 20776128Sphk for (bp = NULL, ++ap; --num; ++ap) { 2088876Srgrimes /* 2091541Srgrimes * Exit the loop if there is no disk address assigned yet and 2101541Srgrimes * the indirect block isn't in the cache, or if we were 2111541Srgrimes * looking for an indirect block and we've found it. 2121541Srgrimes */ 2131541Srgrimes 21476128Sphk metalbn = ap->in_lbn; 215136767Sphk if ((daddr == 0 && !incore(&vp->v_bufobj, metalbn)) || metalbn == bn) 2161541Srgrimes break; 2171541Srgrimes /* 2181541Srgrimes * If we get here, we've either got the block in the cache 2191541Srgrimes * or we have a disk address for it, go fetch it. 2201541Srgrimes */ 2211541Srgrimes if (bp) 22213490Sdyson bqrelse(bp); 2231541Srgrimes 224137039Sphk bp = getblk(vp, metalbn, bsize, 0, 0, 0); 2256875Sdg if ((bp->b_flags & B_CACHE) == 0) { 226251823Spfg#ifdef INVARIANTS 2276875Sdg if (!daddr) 228239372Skevlo panic("ext2_bmaparray: indirect block not in cache"); 2291541Srgrimes#endif 2301541Srgrimes bp->b_blkno = blkptrtodb(ump, daddr); 23158345Sphk bp->b_iocmd = BIO_READ; 23258934Sphk bp->b_flags &= ~B_INVAL; 23358934Sphk bp->b_ioflags &= ~BIO_ERROR; 2345455Sdg vfs_busy_pages(bp, 0); 235121205Sphk bp->b_iooffset = dbtob(bp->b_blkno); 236136927Sphk bstrategy(bp); 237170174Sjeff curthread->td_ru.ru_inblock++; 23859762Sphk error = bufwait(bp); 2393427Sphk if (error) { 2401541Srgrimes brelse(bp); 2411541Srgrimes return (error); 2421541Srgrimes } 2431541Srgrimes } 2441541Srgrimes 245254283Spfg daddr = ((e2fs_daddr_t *)bp->b_data)[ap->in_off]; 24610551Sdyson if (num == 1 && daddr && runp) { 24776128Sphk for (bn = ap->in_off + 1; 2481541Srgrimes bn < MNINDIR(ump) && *runp < maxrun && 24922521Sdyson is_sequential(ump, 250254283Spfg ((e2fs_daddr_t *)bp->b_data)[bn - 1], 251254283Spfg ((e2fs_daddr_t *)bp->b_data)[bn]); 2521541Srgrimes ++bn, ++*runp); 25376128Sphk bn = ap->in_off; 25410551Sdyson if (runb && bn) { 255228583Spfg for (--bn; bn >= 0 && *runb < maxrun && 256262723Spfg is_sequential(ump, 257254283Spfg ((e2fs_daddr_t *)bp->b_data)[bn], 258254283Spfg ((e2fs_daddr_t *)bp->b_data)[bn + 1]); 259262723Spfg --bn, ++*runb); 26010551Sdyson } 26110551Sdyson } 2621541Srgrimes } 2631541Srgrimes if (bp) 26413490Sdyson bqrelse(bp); 2651541Srgrimes 26663788Smckusick /* 26763788Smckusick * Since this is FFS independent code, we are out of scope for the 26863788Smckusick * definitions of BLK_NOCOPY and BLK_SNAP, but we do know that they 26963788Smckusick * will fall in the range 1..um_seqinc, so we use that test and 27063788Smckusick * return a request for a zeroed out buffer if attempts are made 27163788Smckusick * to read a BLK_NOCOPY or BLK_SNAP block. 27263788Smckusick */ 273311232Spfg if ((ip->i_flags & SF_SNAPSHOT) && daddr > 0 && daddr < ump->um_seqinc) { 27463788Smckusick *bnp = -1; 27563788Smckusick return (0); 27663788Smckusick } 27762976Smckusick *bnp = blkptrtodb(ump, daddr); 27862976Smckusick if (*bnp == 0) { 27996596Siedowse *bnp = -1; 28062976Smckusick } 2811541Srgrimes return (0); 2821541Srgrimes} 2831541Srgrimes 2841541Srgrimes/* 2851541Srgrimes * Create an array of logical block number/offset pairs which represent the 2861541Srgrimes * path of indirect blocks required to access a data block. The first "pair" 2871541Srgrimes * contains the logical block number of the appropriate single, double or 2881541Srgrimes * triple indirect block and the offset into the inode indirect block array. 2891541Srgrimes * Note, the logical block number of the inode single/double/triple indirect 2901541Srgrimes * block appears twice in the array, once with the offset into the i_ib and 2911541Srgrimes * once with the offset into the page itself. 2921541Srgrimes */ 2931541Srgrimesint 294254283Spfgext2_getlbns(struct vnode *vp, daddr_t bn, struct indir *ap, int *nump) 2951541Srgrimes{ 296252103Spfg long blockcnt; 297252103Spfg e2fs_lbn_t metalbn, realbn; 29896596Siedowse struct ext2mount *ump; 29931394Sbde int i, numlevels, off; 30031394Sbde int64_t qblockcnt; 3011541Srgrimes 30296596Siedowse ump = VFSTOEXT2(vp->v_mount); 3031541Srgrimes if (nump) 3041541Srgrimes *nump = 0; 3051541Srgrimes numlevels = 0; 3061541Srgrimes realbn = bn; 3071541Srgrimes if ((long)bn < 0) 3081541Srgrimes bn = -(long)bn; 3091541Srgrimes 3101541Srgrimes /* The first NDADDR blocks are direct blocks. */ 3111541Srgrimes if (bn < NDADDR) 3121541Srgrimes return (0); 3131541Srgrimes 3148876Srgrimes /* 3151541Srgrimes * Determine the number of levels of indirection. After this loop 3161541Srgrimes * is done, blockcnt indicates the number of data blocks possible 31731394Sbde * at the previous level of indirection, and NIADDR - i is the number 3181541Srgrimes * of levels of indirection needed to locate the requested block. 3191541Srgrimes */ 3201541Srgrimes for (blockcnt = 1, i = NIADDR, bn -= NDADDR;; i--, bn -= blockcnt) { 3211541Srgrimes if (i == 0) 3221541Srgrimes return (EFBIG); 32331394Sbde /* 32431394Sbde * Use int64_t's here to avoid overflow for triple indirect 32531394Sbde * blocks when longs have 32 bits and the block size is more 32631394Sbde * than 4K. 32731394Sbde */ 32831394Sbde qblockcnt = (int64_t)blockcnt * MNINDIR(ump); 32931394Sbde if (bn < qblockcnt) 3301541Srgrimes break; 33131394Sbde blockcnt = qblockcnt; 3321541Srgrimes } 3331541Srgrimes 3341541Srgrimes /* Calculate the address of the first meta-block. */ 3351541Srgrimes if (realbn >= 0) 3361541Srgrimes metalbn = -(realbn - bn + NIADDR - i); 3371541Srgrimes else 3381541Srgrimes metalbn = -(-realbn - bn + NIADDR - i); 3391541Srgrimes 3408876Srgrimes /* 3411541Srgrimes * At each iteration, off is the offset into the bap array which is 3421541Srgrimes * an array of disk addresses at the current level of indirection. 3431541Srgrimes * The logical block number and the offset in that block are stored 3441541Srgrimes * into the argument array. 3451541Srgrimes */ 3461541Srgrimes ap->in_lbn = metalbn; 3471541Srgrimes ap->in_off = off = NIADDR - i; 3481541Srgrimes ap++; 3491541Srgrimes for (++numlevels; i <= NIADDR; i++) { 3501541Srgrimes /* If searching for a meta-data block, quit when found. */ 3511541Srgrimes if (metalbn == realbn) 3521541Srgrimes break; 3531541Srgrimes 3541541Srgrimes off = (bn / blockcnt) % MNINDIR(ump); 3551541Srgrimes 3561541Srgrimes ++numlevels; 3571541Srgrimes ap->in_lbn = metalbn; 3581541Srgrimes ap->in_off = off; 3591541Srgrimes ++ap; 3601541Srgrimes 3611541Srgrimes metalbn -= -1 + off * blockcnt; 36231394Sbde blockcnt /= MNINDIR(ump); 3631541Srgrimes } 3641541Srgrimes if (nump) 3651541Srgrimes *nump = numlevels; 3661541Srgrimes return (0); 3671541Srgrimes} 368