freebsd-dev/usr.sbin/trim/trim.c
Allan Jude 9d433cb875 trim(8): candelete() returns wrong results because fd is opened O_WRONLY
This was discovered while using trim(8) to test bhyve trim

Reviewed by:	asomers
Differential Revision:	https://reviews.freebsd.org/D24371
2020-04-23 20:14:59 +00:00

246 lines
5.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2019 Eugene Grosbein <eugen@FreeBSD.org>.
* Contains code written by Alan Somers <asomers@FreeBSD.org>.
*
* 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 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 AUTHOR 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.
*
*/
#include <sys/disk.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <libutil.h>
#include <limits.h>
#include <paths.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
static bool candelete(int fd);
static off_t getsize(const char *path);
static int opendev(const char *path, int flags);
static int trim(const char *path, off_t offset, off_t length, bool dryrun, bool verbose);
static void usage(const char *name);
int
main(int argc, char **argv)
{
off_t offset, length;
uint64_t usz;
int ch, error;
bool dryrun, verbose;
char *fname, *name;
error = 0;
length = offset = 0;
name = argv[0];
dryrun = verbose = true;
while ((ch = getopt(argc, argv, "Nfl:o:qr:v")) != -1)
switch (ch) {
case 'N':
dryrun = true;
verbose = true;
break;
case 'f':
dryrun = false;
break;
case 'l':
case 'o':
if (expand_number(optarg, &usz) == -1 ||
(off_t)usz < 0 || (usz == 0 && ch == 'l'))
errx(EX_USAGE,
"invalid %s of the region: %s",
ch == 'o' ? "offset" : "length",
optarg);
if (ch == 'o')
offset = (off_t)usz;
else
length = (off_t)usz;
break;
case 'q':
verbose = false;
break;
case 'r':
if ((length = getsize(optarg)) == 0)
errx(EX_USAGE,
"invalid zero length reference file"
" for the region: %s", optarg);
break;
case 'v':
verbose = true;
break;
default:
usage(name);
/* NOTREACHED */
}
/*
* Safety net: do not allow mistakes like
*
* trim -f /dev/da0 -r rfile
*
* This would trim whole device then error on non-existing file -r.
* Following check prevents this while allowing this form still:
*
* trim -f -- /dev/da0 -r rfile
*/
if (strcmp(argv[optind-1], "--") != 0) {
for (ch = optind; ch < argc; ch++)
if (argv[ch][0] == '-')
usage(name);
}
argv += optind;
argc -= optind;
if (argc < 1)
usage(name);
while ((fname = *argv++) != NULL)
if (trim(fname, offset, length, dryrun, verbose) < 0)
error++;
return (error ? EXIT_FAILURE : EXIT_SUCCESS);
}
static bool
candelete(int fd)
{
struct diocgattr_arg arg;
strlcpy(arg.name, "GEOM::candelete", sizeof(arg.name));
arg.len = sizeof(arg.value.i);
if (ioctl(fd, DIOCGATTR, &arg) == 0)
return (arg.value.i != 0);
else
return (false);
}
static int
opendev(const char *path, int flags)
{
int fd;
char *tstr;
if ((fd = open(path, flags)) < 0) {
if (errno == ENOENT && path[0] != '/') {
if (asprintf(&tstr, "%s%s", _PATH_DEV, path) < 0)
errx(EX_OSERR, "no memory");
fd = open(tstr, flags);
free(tstr);
}
}
if (fd < 0)
err(EX_NOINPUT, "open failed: %s", path);
return (fd);
}
static off_t
getsize(const char *path)
{
struct stat sb;
off_t mediasize;
int fd;
fd = opendev(path, O_RDONLY | O_DIRECT);
if (fstat(fd, &sb) < 0)
err(EX_IOERR, "fstat failed: %s", path);
if (S_ISREG(sb.st_mode) || S_ISDIR(sb.st_mode)) {
close(fd);
return (sb.st_size);
}
if (!S_ISCHR(sb.st_mode) && !S_ISBLK(sb.st_mode))
errx(EX_DATAERR,
"invalid type of the file "
"(not regular, directory nor special device): %s",
path);
if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0)
err(EX_UNAVAILABLE,
"ioctl(DIOCGMEDIASIZE) failed, probably not a disk: "
"%s", path);
close(fd);
return (mediasize);
}
static int
trim(const char *path, off_t offset, off_t length, bool dryrun, bool verbose)
{
off_t arg[2];
int error, fd;
if (length == 0)
length = getsize(path);
if (verbose)
printf("trim %s offset %ju length %ju\n",
path, (uintmax_t)offset, (uintmax_t)length);
if (dryrun) {
printf("dry run: add -f to actually perform the operation\n");
return (0);
}
fd = opendev(path, O_RDWR | O_DIRECT);
arg[0] = offset;
arg[1] = length;
error = ioctl(fd, DIOCGDELETE, arg);
if (error < 0) {
if (errno == EOPNOTSUPP && verbose && !candelete(fd))
warnx("%s: TRIM/UNMAP not supported by driver", path);
else
warn("ioctl(DIOCGDELETE) failed: %s", path);
}
close(fd);
return (error);
}
static void
usage(const char *name)
{
(void)fprintf(stderr,
"usage: %s [-[lo] offset[K|k|M|m|G|g|T|t]] [-r rfile] [-Nfqv] device ...\n",
name);
exit(EX_USAGE);
}