/* $NetBSD: minixfs3.c,v 1.13 2022/04/29 07:42:07 rin Exp $ */
/*-
* Copyright (c) 2012
* Vrije Universiteit, Amsterdam, The Netherlands. All rights reserved.
*
* Author: Evgeniy Ivanov (based on libsa/ext2fs.c).
*
* This code is derived from src/sys/lib/libsa/ext2fs.c contributed to
* The NetBSD Foundation, see copyrights below.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
* IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1997 Manuel Bouyer.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*-
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*
* Copyright (c) 1990, 1991 Carnegie Mellon University
* All Rights Reserved.
*
* Author: David Golub
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or
[email protected]
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
/*
* Stand-alone file reading package for MFS file system.
*/
#include <sys/param.h>
#include <sys/time.h>
#ifdef _STANDALONE
#include <lib/libkern/libkern.h>
#else
#include <stddef.h>
#include <string.h>
#endif
#include "stand.h"
#include "minixfs3.h"
#if defined(LIBSA_FS_SINGLECOMPONENT) && !defined(LIBSA_NO_FS_SYMLINK)
#define LIBSA_NO_FS_SYMLINK
#endif
#if defined(LIBSA_NO_TWIDDLE)
#define twiddle()
#endif
typedef uint32_t ino32_t;
#ifndef FSBTODB
#define FSBTODB(fs, indp) MFS_FSBTODB(fs, indp)
#endif
/*
* To avoid having a lot of filesystem-block sized buffers lurking (which
* could be 32k) we only keep a few entries of the indirect block map.
* With 8k blocks, 2^8 blocks is ~500k so we reread the indirect block
* ~13 times pulling in a 6M kernel.
* The cache size must be smaller than the smallest filesystem block,
* so LN2_IND_CACHE_SZ <= 9 (UFS2 and 4k blocks).
*/
#define LN2_IND_CACHE_SZ 6
#define IND_CACHE_SZ (1 << LN2_IND_CACHE_SZ)
#define IND_CACHE_MASK (IND_CACHE_SZ - 1)
/*
* In-core open file.
*/
struct file {
off_t f_seekp; /* seek pointer */
struct mfs_sblock *f_fs; /* pointer to super-block */
struct mfs_dinode f_di; /* copy of on-disk inode */
uint f_nishift; /* for blocks in indirect block */
block_t f_ind_cache_block;
block_t f_ind_cache[IND_CACHE_SZ];
char *f_buf; /* buffer for data block */
size_t f_buf_size; /* size of data block */
daddr_t f_buf_blkno; /* block number of data block */
};
static int read_inode(ino32_t, struct open_file *);
static int block_map(struct open_file *, block_t, block_t *);
static int buf_read_file(struct open_file *, void *, size_t *);
static int search_directory(const char *, int, struct open_file *, ino32_t *);
static int read_sblock(struct open_file *, struct mfs_sblock *);
/*
* Read a new inode into a file structure.
*/
static int
read_inode(ino32_t inumber, struct open_file *f)
{
struct file *fp = (struct file *)f->f_fsdata;
struct mfs_sblock *fs = fp->f_fs;
char *buf;
size_t rsize;
int rc;
daddr_t inode_sector;
struct mfs_dinode *dip;
inode_sector = FSBTODB(fs, ino_to_fsba(fs, inumber));
/*
* Read inode and save it.
*/
buf = fp->f_buf;
twiddle();
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
inode_sector, fs->mfs_block_size, buf, &rsize);
if (rc)
return rc;
if (rsize != fs->mfs_block_size)
return EIO;
dip = (struct mfs_dinode *)(buf +
INODE_SIZE * ino_to_fsbo(fs, inumber));
mfs_iload(dip, &fp->f_di);
/*
* Clear out the old buffers
*/
fp->f_ind_cache_block = ~0;
fp->f_buf_blkno = -1;
return rc;
}
/*
* Given an offset in a file, find the disk block number (not zone!)
* that contains that block.
*/
static int
block_map(struct open_file *f, block_t file_block, block_t *disk_block_p)
{
struct file *fp = (struct file *)f->f_fsdata;
struct mfs_sblock *fs = fp->f_fs;
uint level;
block_t ind_cache;
block_t ind_block_num;
zone_t zone;
size_t rsize;
int rc;
int boff;
int scale = fs->mfs_log_zone_size; /* for block-zone conversion */
block_t *buf = (void *)fp->f_buf;
/*
* Index structure of an inode:
*
* mdi_blocks[0..NR_DZONES-1]
* hold zone numbers for zones
* 0..NR_DZONES-1
*
* mdi_blocks[NR_DZONES+0]
* block NDADDR+0 is the single indirect block
* holds zone numbers for zones
* NR_DZONES .. NR_DZONES + MFS_NINDIR(fs)-1
*
* mdi_blocks[NR_DZONES+1]
* block NDADDR+1 is the double indirect block
* holds zone numbers for INDEX blocks for zones
* NR_DZONES + MFS_NINDIR(fs) ..
* NR_TZONES + MFS_NINDIR(fs) + MFS_NINDIR(fs)**2 - 1
*/
zone = file_block >> scale;
boff = (int) (file_block - (zone << scale) ); /* relative blk in zone */
if (zone < NR_DZONES) {
/* Direct zone */
zone_t z = fs2h32(fp->f_di.mdi_zone[zone]);
if (z == NO_ZONE) {
*disk_block_p = NO_BLOCK;
return 0;
}
*disk_block_p = (block_t) ((z << scale) + boff);
return 0;
}
zone -= NR_DZONES;
ind_cache = zone >> LN2_IND_CACHE_SZ;
if (ind_cache == fp->f_ind_cache_block) {
*disk_block_p =
fs2h32(fp->f_ind_cache[zone & IND_CACHE_MASK]);
return 0;
}
for (level = 0;;) {
level += fp->f_nishift;
if (zone < (block_t)1 << level)
break;
if (level > NIADDR * fp->f_nishift)
/* Zone number too high */
return EFBIG;
zone -= (block_t)1 << level;
}
ind_block_num =
fs2h32(fp->f_di.mdi_zone[NR_DZONES + (level / fp->f_nishift - 1)]);
for (;;) {
level -= fp->f_nishift;
if (ind_block_num == 0) {
*disk_block_p = NO_BLOCK; /* missing */
return 0;
}
twiddle();
/*
* If we were feeling brave, we could work out the number
* of the disk sector and read a single disk sector instead
* of a filesystem block.
* However we don't do this very often anyway...
*/
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
FSBTODB(fs, ind_block_num), fs->mfs_block_size,
buf, &rsize);
if (rc)
return rc;
if (rsize != fs->mfs_block_size)
return EIO;
ind_block_num = fs2h32(buf[zone >> level]);
if (level == 0)
break;
zone &= (1 << level) - 1;
}
/* Save the part of the block that contains this sector */
memcpy(fp->f_ind_cache, &buf[zone & ~IND_CACHE_MASK],
IND_CACHE_SZ * sizeof fp->f_ind_cache[0]);
fp->f_ind_cache_block = ind_cache;
zone = (zone_t)ind_block_num;
*disk_block_p = (block_t)((zone << scale) + boff);
return 0;
}
/*
* Read a portion of a file into an internal buffer.
* Return the location in the buffer and the amount in the buffer.
*/
static int
buf_read_file(struct open_file *f, void *v, size_t *size_p)
{
char **buf_p = v;
struct file *fp = (struct file *)f->f_fsdata;
struct mfs_sblock *fs = fp->f_fs;
long off;
block_t file_block;
block_t disk_block = 0; /* XXX: gcc */
size_t block_size, nsz;
int rc;
off = mfs_blkoff(fs, fp->f_seekp);
file_block = mfs_lblkno(fs, fp->f_seekp);
block_size = fs->mfs_block_size;
if (file_block != fp->f_buf_blkno) {
rc = block_map(f, file_block, &disk_block);
if (rc)
return rc;
if (disk_block == 0) {
memset(fp->f_buf, 0, block_size);
fp->f_buf_size = block_size;
} else {
twiddle();
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
FSBTODB(fs, disk_block),
block_size, fp->f_buf, &fp->f_buf_size);
if (rc)
return rc;
}
fp->f_buf_blkno = file_block;
}
/*
* Return address of byte in buffer corresponding to
* offset, and size of remainder of buffer after that
* byte.
*/
*buf_p = fp->f_buf + off;
*size_p = block_size - off;
/*
* But truncate buffer at end of file.
*/
nsz = (size_t)(fp->f_di.mdi_size - fp->f_seekp);
if (*size_p > nsz)
*size_p = nsz;
return 0;
}
/*
* Search a directory for a name and return its
* inode number.
*/
static int
search_directory(const char *name, int length, struct open_file *f,
ino32_t *inumber_p)
{
struct file *fp = (struct file *)f->f_fsdata;
struct mfs_sblock *fs = fp->f_fs;
struct mfs_direct *dp;
struct mfs_direct *dbuf;
size_t buf_size;
int namlen;
int rc;
fp->f_seekp = 0;
while (fp->f_seekp < (off_t)fp->f_di.mdi_size) {
rc = buf_read_file(f, (void *)&dbuf, &buf_size);
if (rc)
return rc;
if (buf_size == 0)
return EIO;
/* XXX we assume, that buf_read_file reads an fs block and
* doesn't truncate buffer. Currently i_size in MFS doesn't
* the same as size of allocated blocks, it makes buf_read_file
* to truncate buf_size.
*/
if (buf_size < fs->mfs_block_size)
buf_size = fs->mfs_block_size;
for (dp = dbuf; dp < &dbuf[NR_DIR_ENTRIES(fs)]; dp++) {
char *cp;
if (fs2h32(dp->mfsd_ino) == (ino32_t) 0)
continue;
/* Compute the length of the name */
cp = memchr(dp->mfsd_name, '\0', sizeof(dp->mfsd_name));
if (cp == NULL)
namlen = sizeof(dp->mfsd_name);
else
namlen = cp - (dp->mfsd_name);
if (namlen == length &&
!memcmp(name, dp->mfsd_name, length)) {
/* found entry */
*inumber_p = fs2h32(dp->mfsd_ino);
return 0;
}
}
fp->f_seekp += buf_size;
}
return ENOENT;
}
int
read_sblock(struct open_file *f, struct mfs_sblock *fs)
{
static uint8_t sbbuf[MINBSIZE];
size_t buf_size;
int rc;
/* We must read amount multiple of sector size, hence we can't
* read SBSIZE and read MINBSIZE.
*/
if (SBSIZE > MINBSIZE)
return EINVAL;
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
SUPER_BLOCK_OFF / GETSECSIZE(f), MINBSIZE, sbbuf, &buf_size);
if (rc)
return rc;
if (buf_size != MINBSIZE)
return EIO;
mfs_sbload((void *)sbbuf, fs);
if (fs->mfs_magic != SUPER_MAGIC)
return EINVAL;
if (fs->mfs_block_size < MINBSIZE)
return EINVAL;
if ((fs->mfs_block_size % 512) != 0)
return EINVAL;
if (SBSIZE > fs->mfs_block_size)
return EINVAL;
if ((fs->mfs_block_size % INODE_SIZE) != 0)
return EINVAL;
/* For even larger disks, a similar problem occurs with s_firstdatazone.
* If the on-disk field contains zero, we assume that the value was too
* large to fit, and compute it on the fly.
*/
if (fs->mfs_firstdatazone_old == 0) {
block_t offset;
offset = START_BLOCK + fs->mfs_imap_blocks + fs->mfs_zmap_blocks;
offset += (fs->mfs_ninodes + fs->mfs_inodes_per_block - 1) /
fs->mfs_inodes_per_block;
fs->mfs_firstdatazone =
(offset + (1 << fs->mfs_log_zone_size) - 1) >>
fs->mfs_log_zone_size;
} else {
fs->mfs_firstdatazone = (zone_t) fs->mfs_firstdatazone_old;
}
if (fs->mfs_imap_blocks < 1 || fs->mfs_zmap_blocks < 1
|| fs->mfs_ninodes < 1 || fs->mfs_zones < 1
|| fs->mfs_firstdatazone <= 4
|| fs->mfs_firstdatazone >= fs->mfs_zones
|| (unsigned) fs->mfs_log_zone_size > 4)
return EINVAL;
/* compute in-memory mfs_sblock values */
fs->mfs_inodes_per_block = fs->mfs_block_size / INODE_SIZE;
{
int32_t mult = fs->mfs_block_size >> LOG_MINBSIZE;
int ln2 = LOG_MINBSIZE;
for (; mult != 1; ln2++)
mult >>= 1;
fs->mfs_bshift = ln2;
/* XXX assume hw bsize = 512 */
fs->mfs_fsbtodb = ln2 - LOG_MINBSIZE + 1;
}
fs->mfs_qbmask = fs->mfs_block_size - 1;
fs->mfs_bmask = ~fs->mfs_qbmask;
return 0;
}
/*
* Open a file.
*/
__compactcall int
minixfs3_open(const char *path, struct open_file *f)
{
#ifndef LIBSA_FS_SINGLECOMPONENT
const char *cp, *ncp;
int c;
#endif
ino32_t inumber;
struct file *fp;
struct mfs_sblock *fs;
int rc;
#ifndef LIBSA_NO_FS_SYMLINK
ino32_t parent_inumber;
int nlinks = 0;
char namebuf[MAXPATHLEN+1];
char *buf;
#endif
/* allocate file system specific data structure */
fp = alloc(sizeof(struct file));
memset(fp, 0, sizeof(struct file));
f->f_fsdata = (void *)fp;
/* allocate space and read super block */
fs = alloc(sizeof(*fs));
memset(fs, 0, sizeof(*fs));
fp->f_fs = fs;
twiddle();
rc = read_sblock(f, fs);
if (rc)
goto out;
/* alloc a block sized buffer used for all fs transfers */
fp->f_buf = alloc(fs->mfs_block_size);
/*
* Calculate indirect block levels.
*/
{
int32_t mult;
int ln2;
/*
* We note that the number of indirect blocks is always
* a power of 2. This lets us use shifts and masks instead
* of divide and remainder and avoids pulling in the
* 64bit division routine into the boot code.
*/
mult = MFS_NINDIR(fs);
#ifdef DEBUG
if (!powerof2(mult)) {
/* Hummm was't a power of 2 */
rc = EINVAL;
goto out;
}
#endif
for (ln2 = 0; mult != 1; ln2++)
mult >>= 1;
fp->f_nishift = ln2;
}
inumber = ROOT_INODE;
if ((rc = read_inode(inumber, f)) != 0)
goto out;
#ifndef LIBSA_FS_SINGLECOMPONENT
cp = path;
while (*cp) {
/*
* Remove extra separators
*/
while (*cp == '/')
cp++;
if (*cp == '\0')
break;
/*
* Check that current node is a directory.
*/
if ((fp->f_di.mdi_mode & I_TYPE) != I_DIRECTORY) {
rc = ENOTDIR;
goto out;
}
/*
* Get next component of path name.
*/
ncp = cp;
while ((c = *cp) != '\0' && c != '/')
cp++;
/*
* Look up component in current directory.
* Save directory inumber in case we find a
* symbolic link.
*/
#ifndef LIBSA_NO_FS_SYMLINK
parent_inumber = inumber;
#endif
rc = search_directory(ncp, cp - ncp, f, &inumber);
if (rc)
goto out;
/*
* Open next component.
*/
if ((rc = read_inode(inumber, f)) != 0)
goto out;
#ifndef LIBSA_NO_FS_SYMLINK
/*
* Check for symbolic link.
*/
if ((fp->f_di.mdi_mode & I_TYPE) == I_SYMBOLIC_LINK) {
int link_len = fp->f_di.mdi_size;
int len;
size_t buf_size;
block_t disk_block;
len = strlen(cp);
if (link_len + len > MAXPATHLEN ||
++nlinks > MAXSYMLINKS) {
rc = ENOENT;
goto out;
}
memmove(&namebuf[link_len], cp, len + 1);
/*
* Read file for symbolic link
*/
buf = fp->f_buf;
rc = block_map(f, (block_t)0, &disk_block);
if (rc)
goto out;
twiddle();
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata,
F_READ, FSBTODB(fs, disk_block),
fs->mfs_block_size, buf, &buf_size);
if (rc)
goto out;
memcpy(namebuf, buf, link_len);
/*
* If relative pathname, restart at parent directory.
* If absolute pathname, restart at root.
*/
cp = namebuf;
if (*cp != '/')
inumber = parent_inumber;
else
inumber = (ino32_t) ROOT_INODE;
if ((rc = read_inode(inumber, f)) != 0)
goto out;
}
#endif /* !LIBSA_NO_FS_SYMLINK */
}
/*
* Found terminal component.
*/
rc = 0;
#else /* !LIBSA_FS_SINGLECOMPONENT */
/* look up component in the current (root) directory */
rc = search_directory(path, strlen(path), f, &inumber);
if (rc)
goto out;
/* open it */
rc = read_inode(inumber, f);
#endif /* !LIBSA_FS_SINGLECOMPONENT */
fp->f_seekp = 0; /* reset seek pointer */
out:
if (rc)
minixfs3_close(f);
return rc;
}
__compactcall int
minixfs3_close(struct open_file *f)
{
struct file *fp = (struct file *)f->f_fsdata;
f->f_fsdata = NULL;
if (fp == NULL)
return 0;
if (fp->f_buf)
dealloc(fp->f_buf, fp->f_fs->mfs_block_size);
dealloc(fp->f_fs, sizeof(*fp->f_fs));
dealloc(fp, sizeof(struct file));
return 0;
}
/*
* Copy a portion of a file into kernel memory.
* Cross block boundaries when necessary.
*/
__compactcall int
minixfs3_read(struct open_file *f, void *start, size_t size, size_t *resid)
{
struct file *fp = (struct file *)f->f_fsdata;
size_t csize;
char *buf;
size_t buf_size;
int rc = 0;
char *addr = start;
while (size != 0) {
if (fp->f_seekp >= (off_t)fp->f_di.mdi_size)
break;
rc = buf_read_file(f, &buf, &buf_size);
if (rc)
break;
csize = size;
if (csize > buf_size)
csize = buf_size;
memcpy(addr, buf, csize);
fp->f_seekp += csize;
addr += csize;
size -= csize;
}
if (resid)
*resid = size;
return rc;
}
/*
* Not implemented.
*/
#ifndef LIBSA_NO_FS_WRITE
__compactcall int
minixfs3_write(struct open_file *f, void *start, size_t size, size_t *resid)
{
return EROFS;
}
#endif /* !LIBSA_NO_FS_WRITE */
#ifndef LIBSA_NO_FS_SEEK
__compactcall off_t
minixfs3_seek(struct open_file *f, off_t offset, int where)
{
struct file *fp = (struct file *)f->f_fsdata;
switch (where) {
case SEEK_SET:
fp->f_seekp = offset;
break;
case SEEK_CUR:
fp->f_seekp += offset;
break;
case SEEK_END:
fp->f_seekp = fp->f_di.mdi_size - offset;
break;
default:
return -1;
}
return fp->f_seekp;
}
#endif /* !LIBSA_NO_FS_SEEK */
__compactcall int
minixfs3_stat(struct open_file *f, struct stat *sb)
{
struct file *fp = (struct file *)f->f_fsdata;
/* only important stuff */
memset(sb, 0, sizeof *sb);
sb->st_mode = fp->f_di.mdi_mode;
sb->st_uid = fp->f_di.mdi_uid;
sb->st_gid = fp->f_di.mdi_gid;
sb->st_size = fp->f_di.mdi_size;
return 0;
}
#if defined(LIBSA_ENABLE_LS_OP)
#include "ls.h"
__compactcall void
minixfs3_ls(struct open_file *f, const char *pattern)
{
struct file *fp = (struct file *)f->f_fsdata;
struct mfs_sblock *fs = fp->f_fs;
struct mfs_direct *dp;
struct mfs_direct *dbuf;
size_t buf_size;
lsentry_t *names = 0;
fp->f_seekp = 0;
while (fp->f_seekp < (off_t)fp->f_di.mdi_size) {
int rc = buf_read_file(f, &dbuf, &buf_size);
if (rc)
goto out;
/* XXX we assume, that buf_read_file reads an fs block and
* doesn't truncate buffer. Currently i_size in MFS doesn't
* the same as size of allocated blocks, it makes buf_read_file
* to truncate buf_size.
*/
if (buf_size < fs->mfs_block_size)
buf_size = fs->mfs_block_size;
for (dp = dbuf; dp < &dbuf[NR_DIR_ENTRIES(fs)]; dp++) {
char *cp;
int namlen;
if (fs2h32(dp->mfsd_ino) == 0)
continue;
/* Compute the length of the name,
* We don't use strlen and strcpy, because original MFS
* code doesn't.
*/
cp = memchr(dp->mfsd_name, '\0', sizeof(dp->mfsd_name));
if (cp == NULL)
namlen = sizeof(dp->mfsd_name);
else
namlen = cp - (dp->mfsd_name);
lsadd(&names, pattern, dp->mfsd_name, namlen,
fs2h32(dp->mfsd_ino), "?");
}
fp->f_seekp += buf_size;
}
lsprint(names);
out: lsfree(names);
}
#endif
/*
* byte swap functions for big endian machines
* (mfs is always little endian)
*/
/* These functions are only needed if native byte order is not big endian */
#if BYTE_ORDER == BIG_ENDIAN
void
minixfs3_sb_bswap(struct mfs_sblock *old, struct mfs_sblock *new)
{
new->mfs_ninodes = bswap32(old->mfs_ninodes);
new->mfs_nzones = bswap16(old->mfs_nzones);
new->mfs_imap_blocks = bswap16(old->mfs_imap_blocks);
new->mfs_zmap_blocks = bswap16(old->mfs_zmap_blocks);
new->mfs_firstdatazone_old = bswap16(old->mfs_firstdatazone_old);
new->mfs_log_zone_size = bswap16(old->mfs_log_zone_size);
new->mfs_max_size = bswap32(old->mfs_max_size);
new->mfs_zones = bswap32(old->mfs_zones);
new->mfs_magic = bswap16(old->mfs_magic);
new->mfs_block_size = bswap16(old->mfs_block_size);
new->mfs_disk_version = old->mfs_disk_version;
}
void minixfs3_i_bswap(struct mfs_dinode *old, struct mfs_dinode *new)
{
int i;
new->mdi_mode = bswap16(old->mdi_mode);
new->mdi_nlinks = bswap16(old->mdi_nlinks);
new->mdi_uid = bswap16(old->mdi_uid);
new->mdi_gid = bswap16(old->mdi_gid);
new->mdi_size = bswap32(old->mdi_size);
new->mdi_atime = bswap32(old->mdi_atime);
new->mdi_mtime = bswap32(old->mdi_mtime);
new->mdi_ctime = bswap32(old->mdi_ctime);
/* We don't swap here, because indirects must be swapped later
* anyway, hence everything is done by block_map().
*/
for (i = 0; i < NR_TZONES; i++)
new->mdi_zone[i] = old->mdi_zone[i];
}
#endif
