freebsd-dev/lib/libufs/sblock.c
Kirk McKusick 92c839a156 The libufs library needs to track and free the new fs_si structure
in addition to the fs_csp structure that it references.

PR:           247425
Sponsored by: Netflix
2020-06-23 21:28:26 +00:00

210 lines
5.4 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2002 Juli Mallett. All rights reserved.
*
* This software was written by Juli Mallett <jmallett@FreeBSD.org> for the
* FreeBSD project. Redistribution and use in source and binary forms, with
* or without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistribution of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistribution 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/disklabel.h>
#include <sys/stat.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <libufs.h>
int
sbread(struct uufsd *disk)
{
struct fs *fs;
ERROR(disk, NULL);
if ((errno = sbget(disk->d_fd, &fs, STDSB)) != 0) {
switch (errno) {
case EIO:
ERROR(disk, "non-existent or truncated superblock");
break;
case ENOENT:
ERROR(disk, "no usable known superblock found");
break;
case ENOSPC:
ERROR(disk, "failed to allocate space for superblock "
"information");
break;
case EINVAL:
ERROR(disk, "The previous newfs operation on this "
"volume did not complete.\nYou must complete "
"newfs before using this volume.");
break;
default:
ERROR(disk, "unknown superblock read error");
errno = EIO;
break;
}
disk->d_ufs = 0;
return (-1);
}
memcpy(&disk->d_fs, fs, fs->fs_sbsize);
free(fs);
fs = &disk->d_fs;
if (fs->fs_magic == FS_UFS1_MAGIC)
disk->d_ufs = 1;
if (fs->fs_magic == FS_UFS2_MAGIC)
disk->d_ufs = 2;
disk->d_bsize = fs->fs_fsize / fsbtodb(fs, 1);
disk->d_sblock = fs->fs_sblockloc / disk->d_bsize;
disk->d_si = fs->fs_si;
return (0);
}
int
sbwrite(struct uufsd *disk, int all)
{
struct fs *fs;
int rv;
ERROR(disk, NULL);
rv = ufs_disk_write(disk);
if (rv == -1) {
ERROR(disk, "failed to open disk for writing");
return (-1);
}
fs = &disk->d_fs;
if ((errno = sbput(disk->d_fd, fs, all ? fs->fs_ncg : 0)) != 0) {
switch (errno) {
case EIO:
ERROR(disk, "failed to write superblock");
break;
default:
ERROR(disk, "unknown superblock write error");
errno = EIO;
break;
}
return (-1);
}
return (0);
}
/*
* These are the low-level functions that actually read and write
* the superblock and its associated data. The actual work is done by
* the functions ffs_sbget and ffs_sbput in /sys/ufs/ffs/ffs_subr.c.
*/
static int use_pread(void *devfd, off_t loc, void **bufp, int size);
static int use_pwrite(void *devfd, off_t loc, void *buf, int size);
/*
* Read a superblock from the devfd device allocating memory returned
* in fsp. Also read the superblock summary information.
*/
int
sbget(int devfd, struct fs **fsp, off_t sblockloc)
{
return (ffs_sbget(&devfd, fsp, sblockloc, "user", use_pread));
}
/*
* A read function for use by user-level programs using libufs.
*/
static int
use_pread(void *devfd, off_t loc, void **bufp, int size)
{
int fd;
fd = *(int *)devfd;
if ((*bufp = malloc(size)) == NULL)
return (ENOSPC);
if (pread(fd, *bufp, size, loc) != size)
return (EIO);
return (0);
}
/*
* Write a superblock to the devfd device from the memory pointed to by fs.
* Also write out the superblock summary information but do not free the
* summary information memory.
*
* Additionally write out numaltwrite of the alternate superblocks. Use
* fs->fs_ncg to write out all of the alternate superblocks.
*/
int
sbput(int devfd, struct fs *fs, int numaltwrite)
{
struct csum *savedcsp;
off_t savedactualloc;
int i, error;
if ((error = ffs_sbput(&devfd, fs, fs->fs_sblockactualloc,
use_pwrite)) != 0)
return (error);
if (numaltwrite == 0)
return (0);
savedactualloc = fs->fs_sblockactualloc;
savedcsp = fs->fs_csp;
fs->fs_csp = NULL;
for (i = 0; i < numaltwrite; i++) {
fs->fs_sblockactualloc = dbtob(fsbtodb(fs, cgsblock(fs, i)));
if ((error = ffs_sbput(&devfd, fs, fs->fs_sblockactualloc,
use_pwrite)) != 0) {
fs->fs_sblockactualloc = savedactualloc;
fs->fs_csp = savedcsp;
return (-1);
}
}
fs->fs_sblockactualloc = savedactualloc;
fs->fs_csp = savedcsp;
return (0);
}
/*
* A write function for use by user-level programs using sbput in libufs.
*/
static int
use_pwrite(void *devfd, off_t loc, void *buf, int size)
{
int fd;
fd = *(int *)devfd;
if (pwrite(fd, buf, size, loc) != size)
return (EIO);
return (0);
}