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ufs.c revision 1.41
      1  1.41       dsl /*	$NetBSD: ufs.c,v 1.41 2003/08/27 22:42:08 dsl Exp $	*/
      2   1.8       cgd 
      3   1.1    brezak /*-
      4   1.1    brezak  * Copyright (c) 1993
      5   1.1    brezak  *	The Regents of the University of California.  All rights reserved.
      6   1.1    brezak  *
      7   1.1    brezak  * This code is derived from software contributed to Berkeley by
      8   1.1    brezak  * The Mach Operating System project at Carnegie-Mellon University.
      9   1.1    brezak  *
     10   1.1    brezak  * Redistribution and use in source and binary forms, with or without
     11   1.1    brezak  * modification, are permitted provided that the following conditions
     12   1.1    brezak  * are met:
     13   1.1    brezak  * 1. Redistributions of source code must retain the above copyright
     14   1.1    brezak  *    notice, this list of conditions and the following disclaimer.
     15   1.1    brezak  * 2. Redistributions in binary form must reproduce the above copyright
     16   1.1    brezak  *    notice, this list of conditions and the following disclaimer in the
     17   1.1    brezak  *    documentation and/or other materials provided with the distribution.
     18  1.36       agc  * 3. Neither the name of the University nor the names of its contributors
     19   1.1    brezak  *    may be used to endorse or promote products derived from this software
     20   1.1    brezak  *    without specific prior written permission.
     21   1.1    brezak  *
     22   1.1    brezak  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23   1.1    brezak  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24   1.1    brezak  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25   1.1    brezak  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26   1.1    brezak  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27   1.1    brezak  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28   1.1    brezak  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29   1.1    brezak  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30   1.1    brezak  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31   1.1    brezak  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32   1.1    brezak  * SUCH DAMAGE.
     33  1.22    simonb  *
     34   1.1    brezak  *
     35   1.1    brezak  * Copyright (c) 1990, 1991 Carnegie Mellon University
     36   1.1    brezak  * All Rights Reserved.
     37   1.1    brezak  *
     38   1.1    brezak  * Author: David Golub
     39  1.22    simonb  *
     40   1.1    brezak  * Permission to use, copy, modify and distribute this software and its
     41   1.1    brezak  * documentation is hereby granted, provided that both the copyright
     42   1.1    brezak  * notice and this permission notice appear in all copies of the
     43   1.1    brezak  * software, derivative works or modified versions, and any portions
     44   1.1    brezak  * thereof, and that both notices appear in supporting documentation.
     45  1.22    simonb  *
     46   1.1    brezak  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
     47   1.1    brezak  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
     48   1.1    brezak  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
     49  1.22    simonb  *
     50   1.1    brezak  * Carnegie Mellon requests users of this software to return to
     51  1.22    simonb  *
     52   1.1    brezak  *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
     53   1.1    brezak  *  School of Computer Science
     54   1.1    brezak  *  Carnegie Mellon University
     55   1.1    brezak  *  Pittsburgh PA 15213-3890
     56  1.22    simonb  *
     57   1.1    brezak  * any improvements or extensions that they make and grant Carnegie the
     58   1.1    brezak  * rights to redistribute these changes.
     59  1.27       cgd  */
     60  1.27       cgd 
     61  1.27       cgd /*
     62  1.37       dsl  *	Stand-alone file reading package for UFS and LFS filesystems.
     63   1.1    brezak  */
     64   1.1    brezak 
     65   1.1    brezak #include <sys/param.h>
     66   1.1    brezak #include <sys/time.h>
     67   1.1    brezak #include <ufs/ufs/dinode.h>
     68   1.1    brezak #include <ufs/ufs/dir.h>
     69  1.35       dsl #ifdef LIBSA_LFS
     70  1.35       dsl #include <sys/queue.h>
     71  1.35       dsl #include <sys/mount.h>			/* XXX for MNAMELEN */
     72  1.35       dsl #include <ufs/lfs/lfs.h>
     73  1.35       dsl #else
     74  1.20      ross #include <ufs/ffs/fs.h>
     75  1.35       dsl #endif
     76  1.29   thorpej #ifdef _STANDALONE
     77  1.29   thorpej #include <lib/libkern/libkern.h>
     78  1.29   thorpej #else
     79  1.29   thorpej #include <string.h>
     80  1.29   thorpej #endif
     81   1.2     glass 
     82   1.1    brezak #include "stand.h"
     83  1.35       dsl #ifdef LIBSA_LFS
     84  1.35       dsl #include "lfs.h"
     85  1.35       dsl #else
     86  1.21        pk #include "ufs.h"
     87  1.35       dsl #endif
     88  1.35       dsl 
     89  1.35       dsl /* If this file is compiled by itself, build ufs (aka ffsv1) support */
     90  1.35       dsl #if !defined(LIBSA_FFSv2) && !defined(LIBSA_LFS)
     91  1.35       dsl #define LIBSA_FFSv1
     92  1.35       dsl #endif
     93  1.23       cgd 
     94  1.23       cgd #if defined(LIBSA_FS_SINGLECOMPONENT) && !defined(LIBSA_NO_FS_SYMLINK)
     95  1.23       cgd #define LIBSA_NO_FS_SYMLINK
     96  1.25    simonb #endif
     97  1.25    simonb #if defined(COMPAT_UFS) && defined(LIBSA_NO_COMPAT_UFS)
     98  1.25    simonb #undef COMPAT_UFS
     99  1.23       cgd #endif
    100  1.23       cgd 
    101  1.35       dsl #ifdef LIBSA_LFS
    102  1.35       dsl /*
    103  1.35       dsl  * In-core LFS superblock.  This exists only to placate the macros in lfs.h,
    104  1.35       dsl  */
    105  1.35       dsl struct fs {
    106  1.35       dsl 	struct dlfs	lfs_dlfs;
    107  1.33      fvdl };
    108  1.35       dsl #define fs_magic	lfs_magic
    109  1.35       dsl #define fs_maxsymlinklen lfs_maxsymlinklen
    110  1.33      fvdl 
    111  1.35       dsl #define FS_MAGIC	LFS_MAGIC
    112  1.35       dsl #define SBLOCKSIZE	LFS_SBPAD
    113  1.35       dsl #define SBLOCKOFFSET	LFS_LABELPAD
    114  1.33      fvdl #else
    115  1.35       dsl /* NB ufs2 doesn't use the common suberblock code... */
    116  1.35       dsl #define FS_MAGIC	FS_UFS1_MAGIC
    117  1.35       dsl #define SBLOCKOFFSET	SBLOCK_UFS1
    118  1.35       dsl #endif
    119  1.35       dsl 
    120  1.35       dsl #if defined(LIBSA_NO_TWIDDLE)
    121  1.35       dsl #define twiddle()
    122  1.35       dsl #endif
    123  1.35       dsl 
    124  1.40       dsl #undef cgstart
    125  1.40       dsl #if defined(LIBSA_FFSv2)
    126  1.40       dsl #define cgstart(fc, c) cgstart_ufs2((fs), (c))
    127  1.40       dsl #else
    128  1.40       dsl #define cgstart(fc, c) cgstart_ufs1((fs), (c))
    129  1.40       dsl #endif
    130  1.40       dsl 
    131  1.35       dsl #ifndef ufs_dinode
    132  1.35       dsl #define ufs_dinode	ufs1_dinode
    133  1.35       dsl #endif
    134  1.35       dsl #ifndef indp_t
    135  1.35       dsl #define indp_t		uint32_t
    136  1.35       dsl #endif
    137  1.35       dsl #ifndef FSBTODB
    138  1.40       dsl #define FSBTODB(fs, indp) fsbtodb(fs, indp)
    139  1.33      fvdl #endif
    140  1.23       cgd 
    141   1.1    brezak /*
    142  1.40       dsl  * To avoid having a lot of filesystem-block sized buffers lurking (which
    143  1.40       dsl  * could be 32k) we only keep a few entries of the indirect block map.
    144  1.40       dsl  * With 8k blocks, 2^8 blocks is ~500k so we reread the indirect block
    145  1.40       dsl  * ~13 times pulling in a 6M kernel.
    146  1.40       dsl  * The cache size must be smaller than the smallest filesystem block,
    147  1.40       dsl  * so LN2_IND_CACHE_SZ <= 9 (UFS2 and 4k blocks).
    148  1.40       dsl  */
    149  1.40       dsl #define LN2_IND_CACHE_SZ	6
    150  1.40       dsl #define IND_CACHE_SZ		(1 << LN2_IND_CACHE_SZ)
    151  1.40       dsl #define IND_CACHE_MASK		(IND_CACHE_SZ - 1)
    152  1.40       dsl 
    153  1.40       dsl /*
    154   1.1    brezak  * In-core open file.
    155   1.1    brezak  */
    156   1.1    brezak struct file {
    157   1.1    brezak 	off_t		f_seekp;	/* seek pointer */
    158   1.1    brezak 	struct fs	*f_fs;		/* pointer to super-block */
    159  1.35       dsl 	struct ufs_dinode	f_di;		/* copy of on-disk inode */
    160  1.40       dsl 	uint		f_nishift;	/* for blocks in indirect block */
    161  1.40       dsl 	indp_t		f_ind_cache_block;
    162  1.40       dsl 	indp_t		f_ind_cache[IND_CACHE_SZ];
    163  1.40       dsl 
    164   1.1    brezak 	char		*f_buf;		/* buffer for data block */
    165  1.13       cgd 	size_t		f_buf_size;	/* size of data block */
    166   1.1    brezak 	daddr_t		f_buf_blkno;	/* block number of data block */
    167   1.1    brezak };
    168   1.1    brezak 
    169  1.38       dsl static int read_inode(ino_t, struct open_file *);
    170  1.40       dsl static int block_map(struct open_file *, indp_t, indp_t *);
    171  1.38       dsl static int buf_read_file(struct open_file *, char **, size_t *);
    172  1.38       dsl static int search_directory(const char *, int, struct open_file *, ino_t *);
    173  1.35       dsl #ifdef LIBSA_FFSv1
    174  1.38       dsl static void ffs_oldfscompat(struct fs *);
    175  1.35       dsl #endif
    176  1.35       dsl #ifdef LIBSA_FFSv2
    177  1.38       dsl static int ffs_find_superblock(struct open_file *, struct fs *);
    178  1.35       dsl #endif
    179  1.35       dsl 
    180  1.35       dsl #ifdef LIBSA_LFS
    181  1.35       dsl /*
    182  1.35       dsl  * Find an inode's block.  Look it up in the ifile.  Whee!
    183  1.35       dsl  */
    184  1.35       dsl static int
    185  1.35       dsl find_inode_sector(ino_t inumber, struct open_file *f, daddr_t *isp)
    186  1.35       dsl {
    187  1.35       dsl 	struct file *fp = (struct file *)f->f_fsdata;
    188  1.35       dsl 	struct fs *fs = fp->f_fs;
    189  1.35       dsl 	daddr_t ifileent_blkno;
    190  1.35       dsl 	char *ent_in_buf;
    191  1.35       dsl 	size_t buf_after_ent;
    192  1.35       dsl 	int rc;
    193  1.33      fvdl 
    194  1.35       dsl 	rc = read_inode(fs->lfs_ifile, f);
    195  1.35       dsl 	if (rc)
    196  1.35       dsl 		return (rc);
    197  1.35       dsl 
    198  1.35       dsl 	ifileent_blkno =
    199  1.35       dsl 	    (inumber / fs->lfs_ifpb) + fs->lfs_cleansz + fs->lfs_segtabsz;
    200  1.35       dsl 	fp->f_seekp = (off_t)ifileent_blkno * fs->fs_bsize +
    201  1.35       dsl 	    (inumber % fs->lfs_ifpb) * sizeof (IFILE_Vx);
    202  1.35       dsl 	rc = buf_read_file(f, &ent_in_buf, &buf_after_ent);
    203  1.35       dsl 	if (rc)
    204  1.35       dsl 		return (rc);
    205  1.35       dsl 	/* make sure something's not badly wrong, but don't panic. */
    206  1.35       dsl 	if (buf_after_ent < sizeof (IFILE_Vx))
    207  1.35       dsl 		return (EINVAL);
    208  1.35       dsl 
    209  1.35       dsl 	*isp = FSBTODB(fs, ((IFILE_Vx *)ent_in_buf)->if_daddr);
    210  1.35       dsl 	if (*isp == LFS_UNUSED_DADDR)	/* again, something badly wrong */
    211  1.35       dsl 		return (EINVAL);
    212  1.35       dsl 	return (0);
    213  1.35       dsl }
    214   1.7    brezak #endif
    215   1.7    brezak 
    216   1.1    brezak /*
    217   1.1    brezak  * Read a new inode into a file structure.
    218   1.1    brezak  */
    219   1.1    brezak static int
    220  1.37       dsl read_inode(ino_t inumber, struct open_file *f)
    221   1.1    brezak {
    222  1.30  augustss 	struct file *fp = (struct file *)f->f_fsdata;
    223  1.30  augustss 	struct fs *fs = fp->f_fs;
    224   1.1    brezak 	char *buf;
    225  1.13       cgd 	size_t rsize;
    226   1.1    brezak 	int rc;
    227  1.35       dsl 	daddr_t inode_sector;
    228  1.35       dsl #ifdef LIBSA_LFS
    229  1.35       dsl 	struct ufs_dinode *dip;
    230  1.35       dsl 	int cnt;
    231  1.35       dsl #endif
    232  1.35       dsl 
    233  1.35       dsl #ifdef LIBSA_LFS
    234  1.35       dsl 	if (inumber == fs->lfs_ifile)
    235  1.35       dsl 		inode_sector = FSBTODB(fs, fs->lfs_idaddr);
    236  1.35       dsl 	else if ((rc = find_inode_sector(inumber, f, &inode_sector)) != 0)
    237  1.35       dsl 		return (rc);
    238  1.35       dsl #else
    239  1.35       dsl 	inode_sector = FSBTODB(fs, ino_to_fsba(fs, inumber));
    240  1.35       dsl #endif
    241   1.1    brezak 
    242   1.1    brezak 	/*
    243   1.1    brezak 	 * Read inode and save it.
    244   1.1    brezak 	 */
    245  1.40       dsl 	buf = fp->f_buf;
    246  1.11   mycroft 	twiddle();
    247  1.23       cgd 	rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
    248  1.40       dsl 	    inode_sector, fs->fs_bsize, buf, &rsize);
    249   1.1    brezak 	if (rc)
    250  1.40       dsl 		return rc;
    251  1.40       dsl 	if (rsize != fs->fs_bsize)
    252  1.40       dsl 		return EIO;
    253   1.1    brezak 
    254  1.35       dsl #ifdef LIBSA_LFS
    255  1.35       dsl 	cnt = INOPBx(fs);
    256  1.40       dsl 	dip = (struct ufs_dinode *)buf + (cnt - 1);
    257  1.40       dsl 	for (; dip->di_inumber != inumber; --dip) {
    258  1.40       dsl 		/* kernel code panics, but boot blocks which panic are Bad. */
    259  1.40       dsl 		if (--cnt == 0)
    260  1.40       dsl 			return EINVAL;
    261   1.1    brezak 	}
    262  1.35       dsl 	fp->f_di = *dip;
    263  1.35       dsl #else
    264  1.35       dsl 	fp->f_di = ((struct ufs_dinode *)buf)[ino_to_fsbo(fs, inumber)];
    265  1.35       dsl #endif
    266   1.1    brezak 
    267   1.1    brezak 	/*
    268   1.1    brezak 	 * Clear out the old buffers
    269   1.1    brezak 	 */
    270  1.40       dsl 	fp->f_ind_cache_block = ~0;
    271  1.40       dsl 	fp->f_buf_blkno = -1;
    272  1.22    simonb 	return (rc);
    273   1.1    brezak }
    274   1.1    brezak 
    275   1.1    brezak /*
    276   1.1    brezak  * Given an offset in a file, find the disk block number that
    277   1.1    brezak  * contains that block.
    278   1.1    brezak  */
    279   1.1    brezak static int
    280  1.40       dsl block_map(struct open_file *f, indp_t file_block, indp_t *disk_block_p)
    281   1.1    brezak {
    282  1.30  augustss 	struct file *fp = (struct file *)f->f_fsdata;
    283  1.30  augustss 	struct fs *fs = fp->f_fs;
    284   1.1    brezak 	int level;
    285  1.40       dsl 	indp_t ind_cache;
    286  1.40       dsl 	indp_t ind_block_num;
    287  1.40       dsl 	size_t rsize;
    288   1.1    brezak 	int rc;
    289  1.40       dsl 	indp_t *buf = (void *)fp->f_buf;
    290   1.1    brezak 
    291   1.1    brezak 	/*
    292   1.1    brezak 	 * Index structure of an inode:
    293   1.1    brezak 	 *
    294   1.1    brezak 	 * di_db[0..NDADDR-1]	hold block numbers for blocks
    295   1.1    brezak 	 *			0..NDADDR-1
    296   1.1    brezak 	 *
    297   1.1    brezak 	 * di_ib[0]		index block 0 is the single indirect block
    298   1.1    brezak 	 *			holds block numbers for blocks
    299   1.1    brezak 	 *			NDADDR .. NDADDR + NINDIR(fs)-1
    300   1.1    brezak 	 *
    301   1.1    brezak 	 * di_ib[1]		index block 1 is the double indirect block
    302   1.1    brezak 	 *			holds block numbers for INDEX blocks for blocks
    303   1.1    brezak 	 *			NDADDR + NINDIR(fs) ..
    304   1.1    brezak 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1
    305   1.1    brezak 	 *
    306   1.1    brezak 	 * di_ib[2]		index block 2 is the triple indirect block
    307   1.1    brezak 	 *			holds block numbers for double-indirect
    308   1.1    brezak 	 *			blocks for blocks
    309   1.1    brezak 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2 ..
    310   1.1    brezak 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2
    311   1.1    brezak 	 *				+ NINDIR(fs)**3 - 1
    312   1.1    brezak 	 */
    313   1.1    brezak 
    314   1.1    brezak 	if (file_block < NDADDR) {
    315   1.1    brezak 		/* Direct block. */
    316  1.35       dsl 		*disk_block_p = fp->f_di.di_db[file_block];
    317   1.1    brezak 		return (0);
    318   1.1    brezak 	}
    319   1.1    brezak 
    320   1.1    brezak 	file_block -= NDADDR;
    321   1.1    brezak 
    322  1.40       dsl 	ind_cache = file_block >> LN2_IND_CACHE_SZ;
    323  1.40       dsl 	if (ind_cache == fp->f_ind_cache_block) {
    324  1.40       dsl 		*disk_block_p = fp->f_ind_cache[file_block & IND_CACHE_MASK];
    325  1.40       dsl 		return 0;
    326  1.40       dsl 	}
    327  1.40       dsl 
    328  1.40       dsl 	for (level = 0;;) {
    329  1.40       dsl 		level += fp->f_nishift;
    330  1.40       dsl 		if (file_block < (indp_t)1 << level)
    331  1.40       dsl 			break;
    332  1.40       dsl 		if (level > NIADDR * fp->f_nishift)
    333  1.38       dsl 			/* Block number too high */
    334  1.38       dsl 			return (EFBIG);
    335  1.40       dsl 		file_block -= (indp_t)1 << level;
    336   1.1    brezak 	}
    337   1.1    brezak 
    338  1.40       dsl 	ind_block_num = fp->f_di.di_ib[level / fp->f_nishift - 1];
    339   1.1    brezak 
    340  1.40       dsl 	for (;;) {
    341  1.40       dsl 		level -= fp->f_nishift;
    342   1.1    brezak 		if (ind_block_num == 0) {
    343   1.1    brezak 			*disk_block_p = 0;	/* missing */
    344   1.1    brezak 			return (0);
    345   1.1    brezak 		}
    346   1.1    brezak 
    347  1.40       dsl 		twiddle();
    348  1.40       dsl 		/*
    349  1.40       dsl 		 * If we were feeling brave, we could work out the number
    350  1.40       dsl 		 * of the disk sector and read a single disk sector instead
    351  1.40       dsl 		 * of a filesystem block.
    352  1.40       dsl 		 * However we don't do this very often anyway...
    353  1.40       dsl 		 */
    354  1.40       dsl 		rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
    355  1.40       dsl 			FSBTODB(fp->f_fs, ind_block_num), fs->fs_bsize,
    356  1.40       dsl 			buf, &rsize);
    357  1.40       dsl 		if (rc)
    358  1.40       dsl 			return (rc);
    359  1.40       dsl 		if (rsize != fs->fs_bsize)
    360  1.40       dsl 			return EIO;
    361  1.40       dsl 		ind_block_num = buf[file_block >> level];
    362  1.40       dsl 		if (level == 0)
    363  1.40       dsl 			break;
    364  1.40       dsl 		file_block &= (1 << level) - 1;
    365  1.40       dsl 	}
    366   1.1    brezak 
    367  1.40       dsl 	/* Save the part of the block that contains this sector */
    368  1.40       dsl 	memcpy(fp->f_ind_cache, &buf[file_block & ~IND_CACHE_MASK],
    369  1.40       dsl 	    IND_CACHE_SZ * sizeof fp->f_ind_cache[0]);
    370  1.40       dsl 	fp->f_ind_cache_block = ind_cache;
    371   1.1    brezak 
    372   1.1    brezak 	*disk_block_p = ind_block_num;
    373   1.1    brezak 
    374   1.1    brezak 	return (0);
    375   1.1    brezak }
    376   1.1    brezak 
    377   1.1    brezak /*
    378  1.40       dsl  * Read a portion of a file into an internal buffer.
    379  1.40       dsl  * Return the location in the buffer and the amount in the buffer.
    380   1.1    brezak  */
    381   1.1    brezak static int
    382  1.37       dsl buf_read_file(struct open_file *f, char **buf_p, size_t *size_p)
    383   1.1    brezak {
    384  1.30  augustss 	struct file *fp = (struct file *)f->f_fsdata;
    385  1.30  augustss 	struct fs *fs = fp->f_fs;
    386   1.1    brezak 	long off;
    387  1.40       dsl 	indp_t file_block;
    388  1.40       dsl 	indp_t disk_block;
    389  1.13       cgd 	size_t block_size;
    390   1.1    brezak 	int rc;
    391   1.1    brezak 
    392   1.1    brezak 	off = blkoff(fs, fp->f_seekp);
    393   1.1    brezak 	file_block = lblkno(fs, fp->f_seekp);
    394  1.35       dsl #ifdef LIBSA_LFS
    395  1.35       dsl 	block_size = dblksize(fs, &fp->f_di, file_block);
    396  1.35       dsl #else
    397  1.35       dsl 	block_size = sblksize(fs, fp->f_di.di_size, file_block);
    398  1.35       dsl #endif
    399   1.1    brezak 
    400   1.1    brezak 	if (file_block != fp->f_buf_blkno) {
    401   1.1    brezak 		rc = block_map(f, file_block, &disk_block);
    402   1.1    brezak 		if (rc)
    403   1.1    brezak 			return (rc);
    404   1.1    brezak 
    405   1.1    brezak 		if (disk_block == 0) {
    406  1.41       dsl 			memset(fp->f_buf, 0, block_size);
    407   1.1    brezak 			fp->f_buf_size = block_size;
    408   1.1    brezak 		} else {
    409  1.11   mycroft 			twiddle();
    410  1.23       cgd 			rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
    411  1.35       dsl 				FSBTODB(fs, disk_block),
    412   1.1    brezak 				block_size, fp->f_buf, &fp->f_buf_size);
    413   1.1    brezak 			if (rc)
    414   1.1    brezak 				return (rc);
    415   1.1    brezak 		}
    416   1.1    brezak 
    417   1.1    brezak 		fp->f_buf_blkno = file_block;
    418   1.1    brezak 	}
    419   1.1    brezak 
    420   1.1    brezak 	/*
    421   1.1    brezak 	 * Return address of byte in buffer corresponding to
    422   1.1    brezak 	 * offset, and size of remainder of buffer after that
    423   1.1    brezak 	 * byte.
    424   1.1    brezak 	 */
    425   1.1    brezak 	*buf_p = fp->f_buf + off;
    426   1.1    brezak 	*size_p = block_size - off;
    427   1.1    brezak 
    428   1.1    brezak 	/*
    429   1.1    brezak 	 * But truncate buffer at end of file.
    430   1.1    brezak 	 */
    431  1.35       dsl 	if (*size_p > fp->f_di.di_size - fp->f_seekp)
    432  1.35       dsl 		*size_p = fp->f_di.di_size - fp->f_seekp;
    433   1.1    brezak 
    434   1.1    brezak 	return (0);
    435   1.1    brezak }
    436   1.1    brezak 
    437   1.1    brezak /*
    438   1.1    brezak  * Search a directory for a name and return its
    439  1.38       dsl  * inode number.
    440   1.1    brezak  */
    441   1.1    brezak static int
    442  1.38       dsl search_directory(const char *name, int length, struct open_file *f,
    443  1.38       dsl     ino_t *inumber_p)
    444   1.1    brezak {
    445  1.30  augustss 	struct file *fp = (struct file *)f->f_fsdata;
    446  1.30  augustss 	struct direct *dp;
    447   1.1    brezak 	struct direct *edp;
    448   1.1    brezak 	char *buf;
    449  1.13       cgd 	size_t buf_size;
    450  1.38       dsl 	int namlen;
    451   1.1    brezak 	int rc;
    452   1.1    brezak 
    453   1.1    brezak 	fp->f_seekp = 0;
    454  1.35       dsl 	while (fp->f_seekp < fp->f_di.di_size) {
    455   1.1    brezak 		rc = buf_read_file(f, &buf, &buf_size);
    456   1.1    brezak 		if (rc)
    457   1.1    brezak 			return (rc);
    458   1.1    brezak 
    459   1.1    brezak 		dp = (struct direct *)buf;
    460   1.1    brezak 		edp = (struct direct *)(buf + buf_size);
    461  1.38       dsl 		for (;dp < edp; dp = (void *)((char *)dp + dp->d_reclen)) {
    462  1.40       dsl 			if (dp->d_reclen <= 0)
    463  1.40       dsl 				break;
    464   1.1    brezak 			if (dp->d_ino == (ino_t)0)
    465  1.38       dsl 				continue;
    466   1.1    brezak #if BYTE_ORDER == LITTLE_ENDIAN
    467   1.1    brezak 			if (fp->f_fs->fs_maxsymlinklen <= 0)
    468   1.1    brezak 				namlen = dp->d_type;
    469   1.1    brezak 			else
    470   1.1    brezak #endif
    471   1.1    brezak 				namlen = dp->d_namlen;
    472   1.1    brezak 			if (namlen == length &&
    473  1.38       dsl 			    !memcmp(name, dp->d_name, length)) {
    474   1.1    brezak 				/* found entry */
    475   1.1    brezak 				*inumber_p = dp->d_ino;
    476   1.1    brezak 				return (0);
    477   1.1    brezak 			}
    478   1.1    brezak 		}
    479   1.1    brezak 		fp->f_seekp += buf_size;
    480   1.1    brezak 	}
    481   1.1    brezak 	return (ENOENT);
    482   1.1    brezak }
    483   1.1    brezak 
    484  1.35       dsl #ifdef LIBSA_FFSv2
    485  1.33      fvdl 
    486  1.33      fvdl daddr_t sblock_try[] = SBLOCKSEARCH;
    487  1.33      fvdl 
    488  1.33      fvdl static int
    489  1.37       dsl ffs_find_superblock(struct open_file *f, struct fs *fs)
    490  1.33      fvdl {
    491  1.33      fvdl 	int i, rc;
    492  1.33      fvdl 	size_t buf_size;
    493  1.33      fvdl 
    494  1.33      fvdl 	for (i = 0; sblock_try[i] != -1; i++) {
    495  1.33      fvdl 		rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
    496  1.40       dsl 		    sblock_try[i] / DEV_BSIZE, SBLOCKSIZE, fs, &buf_size);
    497  1.33      fvdl 		if (rc != 0 || buf_size != SBLOCKSIZE)
    498  1.33      fvdl 			return rc;
    499  1.33      fvdl 		if (fs->fs_magic == FS_UFS2_MAGIC) {
    500  1.33      fvdl 			return 0;
    501  1.33      fvdl 		}
    502  1.33      fvdl 	}
    503  1.33      fvdl 	return EINVAL;
    504  1.33      fvdl }
    505  1.33      fvdl 
    506  1.33      fvdl #endif
    507  1.33      fvdl 
    508   1.1    brezak /*
    509   1.1    brezak  * Open a file.
    510   1.1    brezak  */
    511   1.1    brezak int
    512  1.38       dsl ufs_open(const char *path, struct open_file *f)
    513   1.1    brezak {
    514  1.23       cgd #ifndef LIBSA_FS_SINGLECOMPONENT
    515  1.38       dsl 	const char *cp, *ncp;
    516  1.30  augustss 	int c;
    517  1.23       cgd #endif
    518  1.23       cgd 	ino_t inumber;
    519   1.1    brezak 	struct file *fp;
    520   1.1    brezak 	struct fs *fs;
    521  1.10        ws 	int rc;
    522  1.23       cgd #ifndef LIBSA_NO_FS_SYMLINK
    523  1.23       cgd 	ino_t parent_inumber;
    524  1.10        ws 	int nlinks = 0;
    525   1.1    brezak 	char namebuf[MAXPATHLEN+1];
    526  1.40       dsl 	char *buf;
    527  1.22    simonb #endif
    528   1.1    brezak 
    529   1.1    brezak 	/* allocate file system specific data structure */
    530   1.1    brezak 	fp = alloc(sizeof(struct file));
    531  1.41       dsl 	memset(fp, 0, sizeof(struct file));
    532   1.1    brezak 	f->f_fsdata = (void *)fp;
    533   1.1    brezak 
    534   1.1    brezak 	/* allocate space and read super block */
    535  1.33      fvdl 	fs = alloc(SBLOCKSIZE);
    536   1.1    brezak 	fp->f_fs = fs;
    537  1.11   mycroft 	twiddle();
    538  1.33      fvdl 
    539  1.35       dsl #ifdef LIBSA_FFSv2
    540  1.33      fvdl 	rc = ffs_find_superblock(f, fs);
    541  1.33      fvdl 	if (rc)
    542  1.33      fvdl 		goto out;
    543  1.33      fvdl #else
    544  1.35       dsl 	{
    545  1.35       dsl 		size_t buf_size;
    546  1.35       dsl 		rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
    547  1.40       dsl 			SBLOCKOFFSET / DEV_BSIZE, SBLOCKSIZE, fs, &buf_size);
    548  1.35       dsl 		if (rc)
    549  1.35       dsl 			goto out;
    550  1.35       dsl 		if (buf_size != SBLOCKSIZE ||
    551  1.35       dsl #ifdef LIBSA_FFS
    552  1.35       dsl 		    fs->lfs_version != REQUIRED_LFS_VERSION ||
    553  1.35       dsl #endif
    554  1.35       dsl 		    fs->fs_magic != FS_MAGIC) {
    555  1.35       dsl 			rc = EINVAL;
    556  1.35       dsl 			goto out;
    557  1.35       dsl 		}
    558  1.33      fvdl 	}
    559  1.35       dsl #if defined(LIBSA_LFS) && REQUIRED_LFS_VERSION == 2
    560  1.35       dsl 	/*
    561  1.35       dsl 	 * XXX	We should check the second superblock and use the eldest
    562  1.35       dsl 	 *	of the two.  See comments near the top of lfs_mountfs()
    563  1.35       dsl 	 *	in sys/ufs/lfs/lfs_vfsops.c.
    564  1.35       dsl 	 *      This may need a LIBSA_LFS_SMALL check as well.
    565  1.35       dsl 	 */
    566  1.35       dsl #endif
    567  1.33      fvdl #endif
    568   1.1    brezak 
    569  1.35       dsl #ifdef LIBSA_FFSv1
    570  1.33      fvdl 	ffs_oldfscompat(fs);
    571  1.35       dsl #endif
    572  1.33      fvdl 
    573  1.33      fvdl 	if (fs->fs_bsize > MAXBSIZE || fs->fs_bsize < sizeof(struct fs)) {
    574   1.1    brezak 		rc = EINVAL;
    575   1.1    brezak 		goto out;
    576   1.1    brezak 	}
    577   1.1    brezak 
    578   1.1    brezak 	/*
    579   1.1    brezak 	 * Calculate indirect block levels.
    580   1.1    brezak 	 */
    581   1.1    brezak 	{
    582  1.40       dsl 		indp_t mult;
    583  1.35       dsl 		int ln2;
    584  1.35       dsl 
    585  1.35       dsl 		/*
    586  1.35       dsl 		 * We note that the number of indirect blocks is always
    587  1.35       dsl 		 * a power of 2.  This lets us use shifts and masks instead
    588  1.35       dsl 		 * of divide and remainder and avoinds pulling in the
    589  1.35       dsl 		 * 64bit division routine into the boot code.
    590  1.35       dsl 		 */
    591  1.35       dsl 		mult = NINDIR(fs);
    592  1.35       dsl #ifdef DEBUG
    593  1.35       dsl 		if (mult & (mult - 1)) {
    594  1.35       dsl 			/* Hummm was't a power of 2 */
    595  1.35       dsl 			rc = EINVAL;
    596  1.35       dsl 			goto out;
    597  1.35       dsl 		}
    598  1.35       dsl #endif
    599  1.35       dsl 		for (ln2 = 0; mult != 1; ln2++)
    600  1.35       dsl 			mult >>= 1;
    601   1.1    brezak 
    602  1.40       dsl 		fp->f_nishift = ln2;
    603   1.1    brezak 	}
    604   1.1    brezak 
    605  1.40       dsl 	/* alloc a block sized buffer used for all fs transfers */
    606  1.40       dsl 	fp->f_buf = alloc(fs->fs_bsize);
    607   1.1    brezak 	inumber = ROOTINO;
    608   1.1    brezak 	if ((rc = read_inode(inumber, f)) != 0)
    609   1.1    brezak 		goto out;
    610   1.1    brezak 
    611  1.23       cgd #ifndef LIBSA_FS_SINGLECOMPONENT
    612   1.1    brezak 	cp = path;
    613   1.1    brezak 	while (*cp) {
    614   1.1    brezak 
    615   1.1    brezak 		/*
    616   1.1    brezak 		 * Remove extra separators
    617   1.1    brezak 		 */
    618   1.1    brezak 		while (*cp == '/')
    619   1.1    brezak 			cp++;
    620   1.1    brezak 		if (*cp == '\0')
    621   1.1    brezak 			break;
    622   1.1    brezak 
    623   1.1    brezak 		/*
    624   1.1    brezak 		 * Check that current node is a directory.
    625   1.1    brezak 		 */
    626  1.35       dsl 		if ((fp->f_di.di_mode & IFMT) != IFDIR) {
    627   1.1    brezak 			rc = ENOTDIR;
    628   1.1    brezak 			goto out;
    629   1.1    brezak 		}
    630   1.1    brezak 
    631   1.1    brezak 		/*
    632   1.1    brezak 		 * Get next component of path name.
    633   1.1    brezak 		 */
    634  1.38       dsl 		ncp = cp;
    635  1.38       dsl 		while ((c = *cp) != '\0' && c != '/')
    636  1.38       dsl 			cp++;
    637   1.1    brezak 
    638   1.1    brezak 		/*
    639   1.1    brezak 		 * Look up component in current directory.
    640   1.1    brezak 		 * Save directory inumber in case we find a
    641   1.1    brezak 		 * symbolic link.
    642   1.1    brezak 		 */
    643  1.23       cgd #ifndef LIBSA_NO_FS_SYMLINK
    644   1.1    brezak 		parent_inumber = inumber;
    645  1.23       cgd #endif
    646  1.38       dsl 		rc = search_directory(ncp, cp - ncp, f, &inumber);
    647   1.1    brezak 		if (rc)
    648   1.1    brezak 			goto out;
    649   1.1    brezak 
    650   1.1    brezak 		/*
    651   1.1    brezak 		 * Open next component.
    652   1.1    brezak 		 */
    653   1.1    brezak 		if ((rc = read_inode(inumber, f)) != 0)
    654   1.1    brezak 			goto out;
    655   1.1    brezak 
    656  1.23       cgd #ifndef LIBSA_NO_FS_SYMLINK
    657   1.1    brezak 		/*
    658   1.1    brezak 		 * Check for symbolic link.
    659   1.1    brezak 		 */
    660  1.35       dsl 		if ((fp->f_di.di_mode & IFMT) == IFLNK) {
    661  1.35       dsl 			int link_len = fp->f_di.di_size;
    662  1.10        ws 			int len;
    663  1.10        ws 
    664  1.10        ws 			len = strlen(cp);
    665   1.1    brezak 
    666  1.10        ws 			if (link_len + len > MAXPATHLEN ||
    667  1.10        ws 			    ++nlinks > MAXSYMLINKS) {
    668   1.1    brezak 				rc = ENOENT;
    669   1.1    brezak 				goto out;
    670   1.1    brezak 			}
    671   1.1    brezak 
    672  1.38       dsl 			memmove(&namebuf[link_len], cp, len + 1);
    673   1.1    brezak 
    674   1.9        pk 			if (link_len < fs->fs_maxsymlinklen) {
    675  1.38       dsl 				memcpy(namebuf, fp->f_di.di_db, link_len);
    676   1.1    brezak 			} else {
    677   1.1    brezak 				/*
    678   1.1    brezak 				 * Read file for symbolic link
    679   1.1    brezak 				 */
    680  1.13       cgd 				size_t buf_size;
    681  1.40       dsl 				indp_t	disk_block;
    682   1.9        pk 
    683  1.40       dsl 				buf = fp->f_buf;
    684  1.40       dsl 				rc = block_map(f, (indp_t)0, &disk_block);
    685   1.9        pk 				if (rc)
    686   1.9        pk 					goto out;
    687  1.22    simonb 
    688  1.11   mycroft 				twiddle();
    689  1.23       cgd 				rc = DEV_STRATEGY(f->f_dev)(f->f_devdata,
    690  1.35       dsl 					F_READ, FSBTODB(fs, disk_block),
    691   1.9        pk 					fs->fs_bsize, buf, &buf_size);
    692   1.1    brezak 				if (rc)
    693   1.1    brezak 					goto out;
    694   1.1    brezak 
    695  1.38       dsl 				memcpy(namebuf, buf, link_len);
    696   1.1    brezak 			}
    697   1.1    brezak 
    698   1.1    brezak 			/*
    699   1.1    brezak 			 * If relative pathname, restart at parent directory.
    700   1.1    brezak 			 * If absolute pathname, restart at root.
    701   1.1    brezak 			 */
    702   1.1    brezak 			cp = namebuf;
    703   1.1    brezak 			if (*cp != '/')
    704   1.1    brezak 				inumber = parent_inumber;
    705   1.1    brezak 			else
    706   1.1    brezak 				inumber = (ino_t)ROOTINO;
    707   1.1    brezak 
    708   1.9        pk 			if ((rc = read_inode(inumber, f)) != 0)
    709   1.1    brezak 				goto out;
    710   1.1    brezak 		}
    711  1.23       cgd #endif	/* !LIBSA_NO_FS_SYMLINK */
    712   1.1    brezak 	}
    713   1.1    brezak 
    714   1.1    brezak 	/*
    715   1.1    brezak 	 * Found terminal component.
    716   1.1    brezak 	 */
    717   1.1    brezak 	rc = 0;
    718  1.23       cgd 
    719  1.23       cgd #else /* !LIBSA_FS_SINGLECOMPONENT */
    720  1.23       cgd 
    721  1.23       cgd 	/* look up component in the current (root) directory */
    722  1.38       dsl 	rc = search_directory(path, strlen(path), f, &inumber);
    723  1.23       cgd 	if (rc)
    724  1.23       cgd 		goto out;
    725  1.23       cgd 
    726  1.23       cgd 	/* open it */
    727  1.23       cgd 	rc = read_inode(inumber, f);
    728  1.23       cgd 
    729  1.23       cgd #endif /* !LIBSA_FS_SINGLECOMPONENT */
    730  1.26       cgd 
    731  1.26       cgd         fp->f_seekp = 0;		/* reset seek pointer */
    732  1.23       cgd 
    733   1.1    brezak out:
    734  1.40       dsl 	if (rc)
    735  1.38       dsl 		ufs_close(f);
    736   1.1    brezak 	return (rc);
    737   1.1    brezak }
    738   1.1    brezak 
    739   1.1    brezak int
    740  1.37       dsl ufs_close(struct open_file *f)
    741   1.1    brezak {
    742  1.30  augustss 	struct file *fp = (struct file *)f->f_fsdata;
    743   1.1    brezak 
    744  1.38       dsl 	f->f_fsdata = NULL;
    745  1.38       dsl 	if (fp == NULL)
    746   1.1    brezak 		return (0);
    747   1.1    brezak 
    748   1.1    brezak 	if (fp->f_buf)
    749   1.1    brezak 		free(fp->f_buf, fp->f_fs->fs_bsize);
    750  1.33      fvdl 	free(fp->f_fs, SBLOCKSIZE);
    751   1.1    brezak 	free(fp, sizeof(struct file));
    752   1.1    brezak 	return (0);
    753   1.1    brezak }
    754   1.1    brezak 
    755   1.1    brezak /*
    756   1.1    brezak  * Copy a portion of a file into kernel memory.
    757   1.1    brezak  * Cross block boundaries when necessary.
    758   1.1    brezak  */
    759   1.1    brezak int
    760  1.37       dsl ufs_read(struct open_file *f, void *start, size_t size, size_t *resid)
    761   1.1    brezak {
    762  1.30  augustss 	struct file *fp = (struct file *)f->f_fsdata;
    763  1.30  augustss 	size_t csize;
    764   1.1    brezak 	char *buf;
    765  1.13       cgd 	size_t buf_size;
    766   1.1    brezak 	int rc = 0;
    767  1.30  augustss 	char *addr = start;
    768   1.1    brezak 
    769   1.1    brezak 	while (size != 0) {
    770  1.35       dsl 		if (fp->f_seekp >= fp->f_di.di_size)
    771   1.1    brezak 			break;
    772   1.1    brezak 
    773   1.1    brezak 		rc = buf_read_file(f, &buf, &buf_size);
    774   1.1    brezak 		if (rc)
    775   1.1    brezak 			break;
    776   1.1    brezak 
    777   1.1    brezak 		csize = size;
    778   1.1    brezak 		if (csize > buf_size)
    779   1.1    brezak 			csize = buf_size;
    780   1.1    brezak 
    781  1.38       dsl 		memcpy(addr, buf, csize);
    782   1.1    brezak 
    783   1.1    brezak 		fp->f_seekp += csize;
    784  1.12        pk 		addr += csize;
    785   1.1    brezak 		size -= csize;
    786   1.1    brezak 	}
    787   1.1    brezak 	if (resid)
    788   1.1    brezak 		*resid = size;
    789   1.1    brezak 	return (rc);
    790   1.1    brezak }
    791   1.1    brezak 
    792   1.1    brezak /*
    793   1.1    brezak  * Not implemented.
    794   1.1    brezak  */
    795  1.23       cgd #ifndef LIBSA_NO_FS_WRITE
    796   1.1    brezak int
    797  1.37       dsl ufs_write(struct open_file *f, void *start, size_t size, size_t *resid)
    798   1.1    brezak {
    799   1.1    brezak 
    800   1.1    brezak 	return (EROFS);
    801   1.1    brezak }
    802  1.23       cgd #endif /* !LIBSA_NO_FS_WRITE */
    803   1.1    brezak 
    804  1.23       cgd #ifndef LIBSA_NO_FS_SEEK
    805   1.1    brezak off_t
    806  1.37       dsl ufs_seek(struct open_file *f, off_t offset, int where)
    807   1.1    brezak {
    808  1.30  augustss 	struct file *fp = (struct file *)f->f_fsdata;
    809   1.1    brezak 
    810   1.1    brezak 	switch (where) {
    811   1.1    brezak 	case SEEK_SET:
    812   1.1    brezak 		fp->f_seekp = offset;
    813   1.1    brezak 		break;
    814   1.1    brezak 	case SEEK_CUR:
    815   1.1    brezak 		fp->f_seekp += offset;
    816   1.1    brezak 		break;
    817   1.1    brezak 	case SEEK_END:
    818  1.35       dsl 		fp->f_seekp = fp->f_di.di_size - offset;
    819   1.1    brezak 		break;
    820   1.1    brezak 	default:
    821   1.1    brezak 		return (-1);
    822   1.1    brezak 	}
    823   1.1    brezak 	return (fp->f_seekp);
    824   1.1    brezak }
    825  1.23       cgd #endif /* !LIBSA_NO_FS_SEEK */
    826   1.1    brezak 
    827   1.1    brezak int
    828  1.37       dsl ufs_stat(struct open_file *f, struct stat *sb)
    829   1.1    brezak {
    830  1.30  augustss 	struct file *fp = (struct file *)f->f_fsdata;
    831   1.1    brezak 
    832   1.1    brezak 	/* only important stuff */
    833  1.40       dsl 	memset(sb, 0, sizeof *sb);
    834  1.35       dsl 	sb->st_mode = fp->f_di.di_mode;
    835  1.35       dsl 	sb->st_uid = fp->f_di.di_uid;
    836  1.35       dsl 	sb->st_gid = fp->f_di.di_gid;
    837  1.35       dsl 	sb->st_size = fp->f_di.di_size;
    838   1.4        pk 	return (0);
    839   1.4        pk }
    840   1.4        pk 
    841  1.35       dsl #ifdef LIBSA_FFSv1
    842   1.4        pk /*
    843   1.4        pk  * Sanity checks for old file systems.
    844   1.4        pk  *
    845   1.4        pk  * XXX - goes away some day.
    846  1.40       dsl  * Stripped of stuff libsa doesn't need.....
    847   1.4        pk  */
    848  1.13       cgd static void
    849  1.37       dsl ffs_oldfscompat(struct fs *fs)
    850   1.4        pk {
    851   1.4        pk 
    852  1.33      fvdl #ifdef COMPAT_UFS
    853  1.33      fvdl 	if (fs->fs_magic == FS_UFS1_MAGIC &&
    854  1.33      fvdl 	    fs->fs_old_inodefmt < FS_44INODEFMT) {
    855  1.33      fvdl 		fs->fs_qbmask = ~fs->fs_bmask;
    856  1.33      fvdl 		fs->fs_qfmask = ~fs->fs_fmask;
    857  1.33      fvdl 	}
    858  1.33      fvdl #endif
    859   1.1    brezak }
    860  1.35       dsl #endif
    861