freebsd-dev/sbin/dump/traverse.c
Ian Dowse 155ea0634c In mapdirs(), do not use the `dp' inode pointer after searchdir()
has been called, since it points to a shared inode buffer that may
be overwritten. The two cases where `dp' was used incorrectly appear
to have been overlooked when "nodump" inheritance was first added
in revision 1.12.

This is reported to correct propagation of the nodump flag on
directories that are larger than one block in size.

PR:		bin/58912
Submitted by:	Volker Paepcke <vpaepcke@incore.de>
MFC after:	1 week
2003-11-04 14:20:14 +00:00

837 lines
22 KiB
C

/*-
* Copyright (c) 1980, 1988, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)traverse.c 8.7 (Berkeley) 6/15/95";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <ufs/ufs/dir.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#include <protocols/dumprestore.h>
#include <ctype.h>
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <timeconv.h>
#include <unistd.h>
#include "dump.h"
union dinode {
struct ufs1_dinode dp1;
struct ufs2_dinode dp2;
};
#define DIP(dp, field) \
((sblock->fs_magic == FS_UFS1_MAGIC) ? \
(dp)->dp1.field : (dp)->dp2.field)
#define HASDUMPEDFILE 0x1
#define HASSUBDIRS 0x2
static int dirindir(ino_t ino, ufs2_daddr_t blkno, int level, long *size,
long *tapesize, int nodump);
static void dmpindir(ino_t ino, ufs2_daddr_t blk, int level, off_t *size);
static int searchdir(ino_t ino, ufs2_daddr_t blkno, long size, long filesize,
long *tapesize, int nodump);
static long blockest(union dinode *dp);
/*
* This is an estimation of the number of TP_BSIZE blocks in the file.
* It estimates the number of blocks in files with holes by assuming
* that all of the blocks accounted for by di_blocks are data blocks
* (when some of the blocks are usually used for indirect pointers);
* hence the estimate may be high.
*/
static long
blockest(union dinode *dp)
{
long blkest, sizeest;
/*
* dp->di_size is the size of the file in bytes.
* dp->di_blocks stores the number of sectors actually in the file.
* If there are more sectors than the size would indicate, this just
* means that there are indirect blocks in the file or unused
* sectors in the last file block; we can safely ignore these
* (blkest = sizeest below).
* If the file is bigger than the number of sectors would indicate,
* then the file has holes in it. In this case we must use the
* block count to estimate the number of data blocks used, but
* we use the actual size for estimating the number of indirect
* dump blocks (sizeest vs. blkest in the indirect block
* calculation).
*/
if ((DIP(dp, di_flags) & SF_SNAPSHOT) != 0)
return (1);
blkest = howmany(dbtob(DIP(dp, di_blocks)), TP_BSIZE);
sizeest = howmany(DIP(dp, di_size), TP_BSIZE);
if (blkest > sizeest)
blkest = sizeest;
if (DIP(dp, di_size) > sblock->fs_bsize * NDADDR) {
/* calculate the number of indirect blocks on the dump tape */
blkest +=
howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE,
TP_NINDIR);
}
return (blkest + 1);
}
/* Auxiliary macro to pick up files changed since previous dump. */
#define CHANGEDSINCE(dp, t) \
(DIP(dp, di_mtime) >= (t) || DIP(dp, di_ctime) >= (t))
/* The WANTTODUMP macro decides whether a file should be dumped. */
#ifdef UF_NODUMP
#define WANTTODUMP(dp) \
(CHANGEDSINCE(dp, spcl.c_ddate) && \
(nonodump || (DIP(dp, di_flags) & UF_NODUMP) != UF_NODUMP))
#else
#define WANTTODUMP(dp) CHANGEDSINCE(dp, spcl.c_ddate)
#endif
/*
* Dump pass 1.
*
* Walk the inode list for a file system to find all allocated inodes
* that have been modified since the previous dump time. Also, find all
* the directories in the file system.
*/
int
mapfiles(ino_t maxino, long *tapesize)
{
int i, cg, mode, inosused;
int anydirskipped = 0;
union dinode *dp;
struct cg *cgp;
ino_t ino;
char *cp;
if ((cgp = malloc(sblock->fs_cgsize)) == NULL)
quit("mapfiles: cannot allocate memory.\n");
for (cg = 0; cg < sblock->fs_ncg; cg++) {
ino = cg * sblock->fs_ipg;
bread(fsbtodb(sblock, cgtod(sblock, cg)), (char *)cgp,
sblock->fs_cgsize);
if (sblock->fs_magic == FS_UFS2_MAGIC)
inosused = cgp->cg_initediblk;
else
inosused = sblock->fs_ipg;
/*
* If we are using soft updates, then we can trust the
* cylinder group inode allocation maps to tell us which
* inodes are allocated. We will scan the used inode map
* to find the inodes that are really in use, and then
* read only those inodes in from disk.
*/
if (sblock->fs_flags & FS_DOSOFTDEP) {
if (!cg_chkmagic(cgp))
quit("mapfiles: cg %d: bad magic number\n", cg);
cp = &cg_inosused(cgp)[(inosused - 1) / CHAR_BIT];
for ( ; inosused > 0; inosused -= CHAR_BIT, cp--) {
if (*cp == 0)
continue;
for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
if (*cp & i)
break;
inosused--;
}
break;
}
if (inosused <= 0)
continue;
}
for (i = 0; i < inosused; i++, ino++) {
if (ino < ROOTINO ||
(dp = getino(ino, &mode)) == NULL ||
(mode & IFMT) == 0)
continue;
/*
* Everything must go in usedinomap so that a check
* for "in dumpdirmap but not in usedinomap" to detect
* dirs with nodump set has a chance of succeeding
* (this is used in mapdirs()).
*/
SETINO(ino, usedinomap);
if (mode == IFDIR)
SETINO(ino, dumpdirmap);
if (WANTTODUMP(dp)) {
SETINO(ino, dumpinomap);
if (mode != IFREG &&
mode != IFDIR &&
mode != IFLNK)
*tapesize += 1;
else
*tapesize += blockest(dp);
continue;
}
if (mode == IFDIR) {
if (!nonodump &&
(DIP(dp, di_flags) & UF_NODUMP))
CLRINO(ino, usedinomap);
anydirskipped = 1;
}
}
}
/*
* Restore gets very upset if the root is not dumped,
* so ensure that it always is dumped.
*/
SETINO(ROOTINO, dumpinomap);
return (anydirskipped);
}
/*
* Dump pass 2.
*
* Scan each directory on the file system to see if it has any modified
* files in it. If it does, and has not already been added to the dump
* list (because it was itself modified), then add it. If a directory
* has not been modified itself, contains no modified files and has no
* subdirectories, then it can be deleted from the dump list and from
* the list of directories. By deleting it from the list of directories,
* its parent may now qualify for the same treatment on this or a later
* pass using this algorithm.
*/
int
mapdirs(ino_t maxino, long *tapesize)
{
union dinode *dp;
int i, isdir, nodump;
char *map;
ino_t ino;
union dinode di;
long filesize;
int ret, change = 0;
isdir = 0; /* XXX just to get gcc to shut up */
for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
if (((ino - 1) % CHAR_BIT) == 0) /* map is offset by 1 */
isdir = *map++;
else
isdir >>= 1;
/*
* If a directory has been removed from usedinomap, it
* either has the nodump flag set, or has inherited
* it. Although a directory can't be in dumpinomap if
* it isn't in usedinomap, we have to go through it to
* propagate the nodump flag.
*/
nodump = !nonodump && (TSTINO(ino, usedinomap) == 0);
if ((isdir & 1) == 0 || (TSTINO(ino, dumpinomap) && !nodump))
continue;
dp = getino(ino, &i);
/*
* inode buf may change in searchdir().
*/
if (sblock->fs_magic == FS_UFS1_MAGIC)
di.dp1 = dp->dp1;
else
di.dp2 = dp->dp2;
filesize = DIP(&di, di_size);
for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) {
if (DIP(&di, di_db[i]) != 0)
ret |= searchdir(ino, DIP(&di, di_db[i]),
(long)sblksize(sblock, DIP(&di, di_size),
i), filesize, tapesize, nodump);
if (ret & HASDUMPEDFILE)
filesize = 0;
else
filesize -= sblock->fs_bsize;
}
for (i = 0; filesize > 0 && i < NIADDR; i++) {
if (DIP(&di, di_ib[i]) == 0)
continue;
ret |= dirindir(ino, DIP(&di, di_ib[i]), i, &filesize,
tapesize, nodump);
}
if (ret & HASDUMPEDFILE) {
SETINO(ino, dumpinomap);
*tapesize += blockest(&di);
change = 1;
continue;
}
if (nodump) {
if (ret & HASSUBDIRS)
change = 1; /* subdirs inherit nodump */
CLRINO(ino, dumpdirmap);
} else if ((ret & HASSUBDIRS) == 0)
if (!TSTINO(ino, dumpinomap)) {
CLRINO(ino, dumpdirmap);
change = 1;
}
}
return (change);
}
/*
* Read indirect blocks, and pass the data blocks to be searched
* as directories. Quit as soon as any entry is found that will
* require the directory to be dumped.
*/
static int
dirindir(
ino_t ino,
ufs2_daddr_t blkno,
int ind_level,
long *filesize,
long *tapesize,
int nodump)
{
union {
ufs1_daddr_t ufs1[MAXBSIZE / sizeof(ufs1_daddr_t)];
ufs2_daddr_t ufs2[MAXBSIZE / sizeof(ufs2_daddr_t)];
} idblk;
int ret = 0;
int i;
bread(fsbtodb(sblock, blkno), (char *)&idblk, (int)sblock->fs_bsize);
if (ind_level <= 0) {
for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
if (sblock->fs_magic == FS_UFS1_MAGIC)
blkno = idblk.ufs1[i];
else
blkno = idblk.ufs2[i];
if (blkno != 0)
ret |= searchdir(ino, blkno, sblock->fs_bsize,
*filesize, tapesize, nodump);
if (ret & HASDUMPEDFILE)
*filesize = 0;
else
*filesize -= sblock->fs_bsize;
}
return (ret);
}
ind_level--;
for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
if (sblock->fs_magic == FS_UFS1_MAGIC)
blkno = idblk.ufs1[i];
else
blkno = idblk.ufs2[i];
if (blkno != 0)
ret |= dirindir(ino, blkno, ind_level, filesize,
tapesize, nodump);
}
return (ret);
}
/*
* Scan a disk block containing directory information looking to see if
* any of the entries are on the dump list and to see if the directory
* contains any subdirectories.
*/
static int
searchdir(
ino_t ino,
ufs2_daddr_t blkno,
long size,
long filesize,
long *tapesize,
int nodump)
{
int mode;
struct direct *dp;
union dinode *ip;
long loc, ret = 0;
static caddr_t dblk;
if (dblk == NULL && (dblk = malloc(sblock->fs_bsize)) == NULL)
quit("searchdir: cannot allocate indirect memory.\n");
bread(fsbtodb(sblock, blkno), dblk, (int)size);
if (filesize < size)
size = filesize;
for (loc = 0; loc < size; ) {
dp = (struct direct *)(dblk + loc);
if (dp->d_reclen == 0) {
msg("corrupted directory, inumber %d\n", ino);
break;
}
loc += dp->d_reclen;
if (dp->d_ino == 0)
continue;
if (dp->d_name[0] == '.') {
if (dp->d_name[1] == '\0')
continue;
if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
continue;
}
if (nodump) {
ip = getino(dp->d_ino, &mode);
if (TSTINO(dp->d_ino, dumpinomap)) {
CLRINO(dp->d_ino, dumpinomap);
*tapesize -= blockest(ip);
}
/*
* Add back to dumpdirmap and remove from usedinomap
* to propagate nodump.
*/
if (mode == IFDIR) {
SETINO(dp->d_ino, dumpdirmap);
CLRINO(dp->d_ino, usedinomap);
ret |= HASSUBDIRS;
}
} else {
if (TSTINO(dp->d_ino, dumpinomap)) {
ret |= HASDUMPEDFILE;
if (ret & HASSUBDIRS)
break;
}
if (TSTINO(dp->d_ino, dumpdirmap)) {
ret |= HASSUBDIRS;
if (ret & HASDUMPEDFILE)
break;
}
}
}
return (ret);
}
/*
* Dump passes 3 and 4.
*
* Dump the contents of an inode to tape.
*/
void
dumpino(union dinode *dp, ino_t ino)
{
int ind_level, cnt;
off_t size;
char buf[TP_BSIZE];
if (newtape) {
newtape = 0;
dumpmap(dumpinomap, TS_BITS, ino);
}
CLRINO(ino, dumpinomap);
/*
* Zero out the size of a snapshot so that it will be dumped
* as a zero length file.
*/
if ((DIP(dp, di_flags) & SF_SNAPSHOT) != 0) {
DIP(dp, di_size) = 0;
DIP(dp, di_flags) &= ~SF_SNAPSHOT;
}
if (sblock->fs_magic == FS_UFS1_MAGIC) {
spcl.c_mode = dp->dp1.di_mode;
spcl.c_size = dp->dp1.di_size;
spcl.c_atime = _time32_to_time(dp->dp1.di_atime);
spcl.c_atimensec = dp->dp1.di_atimensec;
spcl.c_mtime = _time32_to_time(dp->dp1.di_mtime);
spcl.c_mtimensec = dp->dp1.di_mtimensec;
spcl.c_birthtime = 0;
spcl.c_birthtimensec = 0;
spcl.c_rdev = dp->dp1.di_rdev;
spcl.c_file_flags = dp->dp1.di_flags;
spcl.c_uid = dp->dp1.di_uid;
spcl.c_gid = dp->dp1.di_gid;
} else {
spcl.c_mode = dp->dp2.di_mode;
spcl.c_size = dp->dp2.di_size;
spcl.c_atime = _time64_to_time(dp->dp2.di_atime);
spcl.c_atimensec = dp->dp2.di_atimensec;
spcl.c_mtime = _time64_to_time(dp->dp2.di_mtime);
spcl.c_mtimensec = dp->dp2.di_mtimensec;
spcl.c_birthtime = _time64_to_time(dp->dp2.di_birthtime);
spcl.c_birthtimensec = dp->dp2.di_birthnsec;
spcl.c_rdev = dp->dp2.di_rdev;
spcl.c_file_flags = dp->dp2.di_flags;
spcl.c_uid = dp->dp2.di_uid;
spcl.c_gid = dp->dp2.di_gid;
}
spcl.c_type = TS_INODE;
spcl.c_count = 0;
switch (DIP(dp, di_mode) & S_IFMT) {
case 0:
/*
* Freed inode.
*/
return;
case S_IFLNK:
/*
* Check for short symbolic link.
*/
if (DIP(dp, di_size) > 0 &&
DIP(dp, di_size) < sblock->fs_maxsymlinklen) {
spcl.c_addr[0] = 1;
spcl.c_count = 1;
writeheader(ino);
if (sblock->fs_magic == FS_UFS1_MAGIC)
memmove(buf, (caddr_t)dp->dp1.di_db,
(u_long)DIP(dp, di_size));
else
memmove(buf, (caddr_t)dp->dp2.di_db,
(u_long)DIP(dp, di_size));
buf[DIP(dp, di_size)] = '\0';
writerec(buf, 0);
return;
}
/* FALLTHROUGH */
case S_IFDIR:
case S_IFREG:
if (DIP(dp, di_size) > 0)
break;
/* FALLTHROUGH */
case S_IFIFO:
case S_IFSOCK:
case S_IFCHR:
case S_IFBLK:
writeheader(ino);
return;
default:
msg("Warning: undefined file type 0%o\n",
DIP(dp, di_mode) & IFMT);
return;
}
if (DIP(dp, di_size) > NDADDR * sblock->fs_bsize)
cnt = NDADDR * sblock->fs_frag;
else
cnt = howmany(DIP(dp, di_size), sblock->fs_fsize);
if (sblock->fs_magic == FS_UFS1_MAGIC)
ufs1_blksout(&dp->dp1.di_db[0], cnt, ino);
else
ufs2_blksout(&dp->dp2.di_db[0], cnt, ino);
if ((size = DIP(dp, di_size) - NDADDR * sblock->fs_bsize) <= 0)
return;
for (ind_level = 0; ind_level < NIADDR; ind_level++) {
dmpindir(ino, DIP(dp, di_ib[ind_level]), ind_level, &size);
if (size <= 0)
return;
}
}
/*
* Read indirect blocks, and pass the data blocks to be dumped.
*/
static void
dmpindir(ino_t ino, ufs2_daddr_t blk, int ind_level, off_t *size)
{
union {
ufs1_daddr_t ufs1[MAXBSIZE / sizeof(ufs1_daddr_t)];
ufs2_daddr_t ufs2[MAXBSIZE / sizeof(ufs2_daddr_t)];
} idblk;
int i, cnt;
if (blk != 0)
bread(fsbtodb(sblock, blk), (char *)&idblk,
(int)sblock->fs_bsize);
else
memset(&idblk, 0, sblock->fs_bsize);
if (ind_level <= 0) {
if (*size < NINDIR(sblock) * sblock->fs_bsize)
cnt = howmany(*size, sblock->fs_fsize);
else
cnt = NINDIR(sblock) * sblock->fs_frag;
*size -= NINDIR(sblock) * sblock->fs_bsize;
if (sblock->fs_magic == FS_UFS1_MAGIC)
ufs1_blksout(idblk.ufs1, cnt, ino);
else
ufs2_blksout(idblk.ufs2, cnt, ino);
return;
}
ind_level--;
for (i = 0; i < NINDIR(sblock); i++) {
if (sblock->fs_magic == FS_UFS1_MAGIC)
dmpindir(ino, idblk.ufs1[i], ind_level, size);
else
dmpindir(ino, idblk.ufs2[i], ind_level, size);
if (*size <= 0)
return;
}
}
/*
* Collect up the data into tape record sized buffers and output them.
*/
void
ufs1_blksout(ufs1_daddr_t *blkp, int frags, ino_t ino)
{
ufs1_daddr_t *bp;
int i, j, count, blks, tbperdb;
blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
tbperdb = sblock->fs_bsize >> tp_bshift;
for (i = 0; i < blks; i += TP_NINDIR) {
if (i + TP_NINDIR > blks)
count = blks;
else
count = i + TP_NINDIR;
for (j = i; j < count; j++)
if (blkp[j / tbperdb] != 0)
spcl.c_addr[j - i] = 1;
else
spcl.c_addr[j - i] = 0;
spcl.c_count = count - i;
writeheader(ino);
bp = &blkp[i / tbperdb];
for (j = i; j < count; j += tbperdb, bp++)
if (*bp != 0) {
if (j + tbperdb <= count)
dumpblock(*bp, (int)sblock->fs_bsize);
else
dumpblock(*bp, (count - j) * TP_BSIZE);
}
spcl.c_type = TS_ADDR;
}
}
/*
* Collect up the data into tape record sized buffers and output them.
*/
void
ufs2_blksout(ufs2_daddr_t *blkp, int frags, ino_t ino)
{
ufs2_daddr_t *bp;
int i, j, count, blks, tbperdb;
blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
tbperdb = sblock->fs_bsize >> tp_bshift;
for (i = 0; i < blks; i += TP_NINDIR) {
if (i + TP_NINDIR > blks)
count = blks;
else
count = i + TP_NINDIR;
for (j = i; j < count; j++)
if (blkp[j / tbperdb] != 0)
spcl.c_addr[j - i] = 1;
else
spcl.c_addr[j - i] = 0;
spcl.c_count = count - i;
writeheader(ino);
bp = &blkp[i / tbperdb];
for (j = i; j < count; j += tbperdb, bp++)
if (*bp != 0) {
if (j + tbperdb <= count)
dumpblock(*bp, (int)sblock->fs_bsize);
else
dumpblock(*bp, (count - j) * TP_BSIZE);
}
spcl.c_type = TS_ADDR;
}
}
/*
* Dump a map to the tape.
*/
void
dumpmap(char *map, int type, ino_t ino)
{
int i;
char *cp;
spcl.c_type = type;
spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
writeheader(ino);
for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
writerec(cp, 0);
}
/*
* Write a header record to the dump tape.
*/
void
writeheader(ino_t ino)
{
int32_t sum, cnt, *lp;
spcl.c_inumber = ino;
spcl.c_magic = FS_UFS2_MAGIC;
spcl.c_checksum = 0;
lp = (int32_t *)&spcl;
sum = 0;
cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t));
while (--cnt >= 0) {
sum += *lp++;
sum += *lp++;
sum += *lp++;
sum += *lp++;
}
spcl.c_checksum = CHECKSUM - sum;
writerec((char *)&spcl, 1);
}
union dinode *
getino(ino_t inum, int *modep)
{
static ino_t minino, maxino;
static caddr_t inoblock;
struct ufs1_dinode *dp1;
struct ufs2_dinode *dp2;
if (inoblock == NULL && (inoblock = malloc(sblock->fs_bsize)) == NULL)
quit("cannot allocate inode memory.\n");
curino = inum;
if (inum >= minino && inum < maxino)
goto gotit;
bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), inoblock,
(int)sblock->fs_bsize);
minino = inum - (inum % INOPB(sblock));
maxino = minino + INOPB(sblock);
gotit:
if (sblock->fs_magic == FS_UFS1_MAGIC) {
dp1 = &((struct ufs1_dinode *)inoblock)[inum - minino];
*modep = (dp1->di_mode & IFMT);
return ((union dinode *)dp1);
}
dp2 = &((struct ufs2_dinode *)inoblock)[inum - minino];
*modep = (dp2->di_mode & IFMT);
return ((union dinode *)dp2);
}
/*
* Read a chunk of data from the disk.
* Try to recover from hard errors by reading in sector sized pieces.
* Error recovery is attempted at most BREADEMAX times before seeking
* consent from the operator to continue.
*/
int breaderrors = 0;
#define BREADEMAX 32
void
bread(ufs2_daddr_t blkno, char *buf, int size)
{
int secsize, bytes, resid, xfer, base, cnt, i;
static char *tmpbuf;
off_t offset;
loop:
offset = blkno << dev_bshift;
secsize = sblock->fs_fsize;
base = offset % secsize;
resid = size % secsize;
/*
* If the transfer request starts or ends on a non-sector
* boundary, we must read the entire sector and copy out
* just the part that we need.
*/
if (base == 0 && resid == 0) {
cnt = cread(diskfd, buf, size, offset);
if (cnt == size)
return;
} else {
if (tmpbuf == NULL && (tmpbuf = malloc(secsize)) == 0)
quit("buffer malloc failed\n");
xfer = 0;
bytes = size;
if (base != 0) {
cnt = cread(diskfd, tmpbuf, secsize, offset - base);
if (cnt != secsize)
goto bad;
xfer = secsize - base;
offset += xfer;
bytes -= xfer;
resid = bytes % secsize;
memcpy(buf, &tmpbuf[base], xfer);
}
if (bytes >= secsize) {
cnt = cread(diskfd, &buf[xfer], bytes - resid, offset);
if (cnt != bytes - resid)
goto bad;
xfer += cnt;
offset += cnt;
}
if (resid == 0)
return;
cnt = cread(diskfd, tmpbuf, secsize, offset);
if (cnt == secsize) {
memcpy(&buf[xfer], tmpbuf, resid);
return;
}
}
bad:
if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
/*
* Trying to read the final fragment.
*
* NB - dump only works in TP_BSIZE blocks, hence
* rounds `dev_bsize' fragments up to TP_BSIZE pieces.
* It should be smarter about not actually trying to
* read more than it can get, but for the time being
* we punt and scale back the read only when it gets
* us into trouble. (mkm 9/25/83)
*/
size -= dev_bsize;
goto loop;
}
if (cnt == -1)
msg("read error from %s: %s: [block %jd]: count=%d\n",
disk, strerror(errno), (intmax_t)blkno, size);
else
msg("short read error from %s: [block %jd]: count=%d, got=%d\n",
disk, (intmax_t)blkno, size, cnt);
if (++breaderrors > BREADEMAX) {
msg("More than %d block read errors from %s\n",
BREADEMAX, disk);
broadcast("DUMP IS AILING!\n");
msg("This is an unrecoverable error.\n");
if (!query("Do you want to attempt to continue?")){
dumpabort(0);
/*NOTREACHED*/
} else
breaderrors = 0;
}
/*
* Zero buffer, then try to read each sector of buffer separately,
* and bypass the cache.
*/
memset(buf, 0, size);
for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
if ((cnt = pread(diskfd, buf, (int)dev_bsize,
((off_t)blkno << dev_bshift))) == dev_bsize)
continue;
if (cnt == -1) {
msg("read error from %s: %s: [sector %jd]: count=%ld\n",
disk, strerror(errno), (intmax_t)blkno, dev_bsize);
continue;
}
msg("short read from %s: [sector %jd]: count=%ld, got=%d\n",
disk, (intmax_t)blkno, dev_bsize, cnt);
}
}