/*
* fstrim.c -- discard the part (or whole) of mounted filesystem.
*
* Copyright (C) 2010 Red Hat, Inc. All rights reserved.
* Written by Lukas Czerner <lczerner@redhat.com>
* Karel Zak <kzak@redhat.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*
* This program uses FITRIM ioctl to discard parts or the whole filesystem
* online (mounted). You can specify range (start and length) to be
* discarded, or simply discard whole filesystem.
*/
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <fcntl.h>
#include <limits.h>
#include <getopt.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include "nls.h"
#include "strutils.h"
#include "c.h"
#include "closestream.h"
#include "pathnames.h"
#include "sysfs.h"
#include <libmount.h>
/* We cannot include linux/fs.h due to MS_* constants collision with
* sys/mount.h (and libmount.h)
*/
#ifndef FITRIM
struct fstrim_range {
uint64_t start;
uint64_t len;
uint64_t minlen;
};
#define FITRIM _IOWR('X', 121, struct fstrim_range)
#endif
/* returns: 0 = success, 1 = unsupported, < 0 = error */
static int fstrim_filesystem(const char *path, struct fstrim_range *rangetpl,
int verbose)
{
int fd, rc;
struct stat sb;
struct fstrim_range range;
/* kernel modifies the range */
memcpy(&range, rangetpl, sizeof(range));
fd = open(path, O_RDONLY);
if (fd < 0) {
warn(_("cannot open %s"), path);
rc = -errno;
goto done;
}
if (fstat(fd, &sb) == -1) {
warn(_("stat of %s failed"), path);
rc = -errno;
goto done;
}
if (!S_ISDIR(sb.st_mode)) {
warnx(_("%s: not a directory"), path);
rc = -EINVAL;
goto done;
}
errno = 0;
if (ioctl(fd, FITRIM, &range)) {
rc = errno == EOPNOTSUPP || errno == ENOTTY ? 1 : -errno;
if (rc != 1)
warn(_("%s: FITRIM ioctl failed"), path);
goto done;
}
if (verbose) {
char *str = size_to_human_string(
SIZE_SUFFIX_3LETTER | SIZE_SUFFIX_SPACE,
(uint64_t) range.len);
/* TRANSLATORS: The standard value here is a very large number. */
printf(_("%s: %s (%" PRIu64 " bytes) trimmed\n"),
path, str, (uint64_t) range.len);
free(str);
}
rc = 0;
done:
if (fd >= 0)
close(fd);
return rc;
}
static int has_discard(const char *devname, struct sysfs_cxt *wholedisk)
{
struct sysfs_cxt cxt, *parent = NULL;
uint64_t dg = 0;
dev_t disk = 0, dev;
int rc;
dev = sysfs_devname_to_devno(devname, NULL);
if (!dev)
return 1;
/*
* This is tricky to read the info from sys/, because the queue
* attributes are provided for whole devices (disk) only. We're trying
* to reuse the whole-disk sysfs context to optimize this stuff (as
* system usually have just one disk only).
*/
if (sysfs_devno_to_wholedisk(dev, NULL, 0, &disk) || !disk)
return 1;
if (dev != disk) {
if (wholedisk->devno != disk) {
sysfs_deinit(wholedisk);
if (sysfs_init(wholedisk, disk, NULL))
return 1;
}
parent = wholedisk;
}
rc = sysfs_init(&cxt, dev, parent);
if (!rc)
rc = sysfs_read_u64(&cxt, "queue/discard_granularity", &dg);
sysfs_deinit(&cxt);
return rc == 0 && dg > 0;
}
static int uniq_fs_target_cmp(
struct libmnt_table *tb __attribute__((__unused__)),
struct libmnt_fs *a,
struct libmnt_fs *b)
{
return !mnt_fs_streq_target(a, mnt_fs_get_target(b));
}
static int uniq_fs_source_cmp(
struct libmnt_table *tb __attribute__((__unused__)),
struct libmnt_fs *a,
struct libmnt_fs *b)
{
if (mnt_fs_is_pseudofs(a) || mnt_fs_is_netfs(a) ||
mnt_fs_is_pseudofs(b) || mnt_fs_is_netfs(b))
return 1;
return !mnt_fs_streq_srcpath(a, mnt_fs_get_srcpath(b));
}
/*
* fstrim --all follows "mount -a" return codes:
*
* 0 = all success
* 32 = all failed
* 64 = some failed, some success
*/
static int fstrim_all(struct fstrim_range *rangetpl, int verbose)
{
struct libmnt_fs *fs;
struct libmnt_iter *itr;
struct libmnt_table *tab;
struct sysfs_cxt wholedisk = UL_SYSFSCXT_EMPTY;
int cnt = 0, cnt_err = 0;
mnt_init_debug(0);
itr = mnt_new_iter(MNT_ITER_BACKWARD);
if (!itr)
err(MNT_EX_FAIL, _("failed to initialize libmount iterator"));
tab = mnt_new_table_from_file(_PATH_PROC_MOUNTINFO);
if (!tab)
err(MNT_EX_FAIL, _("failed to parse %s"), _PATH_PROC_MOUNTINFO);
/* de-duplicate by mountpoints */
mnt_table_uniq_fs(tab, 0, uniq_fs_target_cmp);
/* de-duplicate by source */
mnt_table_uniq_fs(tab, MNT_UNIQ_FORWARD, uniq_fs_source_cmp);
while (mnt_table_next_fs(tab, itr, &fs) == 0) {
const char *src = mnt_fs_get_srcpath(fs),
*tgt = mnt_fs_get_target(fs);
char *path;
int rc = 1;
if (!src || !tgt || *src != '/' ||
mnt_fs_is_pseudofs(fs) ||
mnt_fs_is_netfs(fs))
continue;
/* Is it really accessible mountpoint? Not all mountpoints are
* accessible (maybe over mounted by another filesystem) */
path = mnt_get_mountpoint(tgt);
if (path && strcmp(path, tgt) == 0)
rc = 0;
free(path);
if (rc)
continue; /* overlaying mount */
if (!has_discard(src, &wholedisk))
continue;
cnt++;
/*
* We're able to detect that the device supports discard, but
* things also depend on filesystem or device mapping, for
* example vfat or LUKS (by default) does not support FSTRIM.
*
* This is reason why we ignore EOPNOTSUPP and ENOTTY errors
* from discard ioctl.
*/
if (fstrim_filesystem(tgt, rangetpl, verbose) < 0)
cnt_err++;
}
sysfs_deinit(&wholedisk);
mnt_unref_table(tab);
mnt_free_iter(itr);
if (cnt && cnt == cnt_err)
return MNT_EX_FAIL; /* all failed */
if (cnt && cnt_err)
return MNT_EX_SOMEOK; /* some ok */
return EXIT_SUCCESS;
}
static void __attribute__((__noreturn__)) usage(void)
{
FILE *out = stdout;
fputs(USAGE_HEADER, out);
fprintf(out,
_(" %s [options] <mount point>\n"), program_invocation_short_name);
fputs(USAGE_SEPARATOR, out);
fputs(_("Discard unused blocks on a mounted filesystem.\n"), out);
fputs(USAGE_OPTIONS, out);
fputs(_(" -a, --all trim all mounted filesystems that are supported\n"), out);
fputs(_(" -o, --offset <num> the offset in bytes to start discarding from\n"), out);
fputs(_(" -l, --length <num> the number of bytes to discard\n"), out);
fputs(_(" -m, --minimum <num> the minimum extent length to discard\n"), out);
fputs(_(" -v, --verbose print number of discarded bytes\n"), out);
fputs(USAGE_SEPARATOR, out);
printf(USAGE_HELP_OPTIONS(21));
printf(USAGE_MAN_TAIL("fstrim(8)"));
exit(EXIT_SUCCESS);
}
int main(int argc, char **argv)
{
char *path = NULL;
int c, rc, verbose = 0, all = 0;
struct fstrim_range range;
static const struct option longopts[] = {
{ "all", no_argument, NULL, 'a' },
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, 'V' },
{ "offset", required_argument, NULL, 'o' },
{ "length", required_argument, NULL, 'l' },
{ "minimum", required_argument, NULL, 'm' },
{ "verbose", no_argument, NULL, 'v' },
{ NULL, 0, NULL, 0 }
};
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
atexit(close_stdout);
memset(&range, 0, sizeof(range));
range.len = ULLONG_MAX;
while ((c = getopt_long(argc, argv, "ahVo:l:m:v", longopts, NULL)) != -1) {
switch(c) {
case 'a':
all = 1;
break;
case 'h':
usage();
break;
case 'V':
printf(UTIL_LINUX_VERSION);
return EXIT_SUCCESS;
case 'l':
range.len = strtosize_or_err(optarg,
_("failed to parse length"));
break;
case 'o':
range.start = strtosize_or_err(optarg,
_("failed to parse offset"));
break;
case 'm':
range.minlen = strtosize_or_err(optarg,
_("failed to parse minimum extent length"));
break;
case 'v':
verbose = 1;
break;
default:
errtryhelp(EXIT_FAILURE);
break;
}
}
if (!all) {
if (optind == argc)
errx(EXIT_FAILURE, _("no mountpoint specified"));
path = argv[optind++];
}
if (optind != argc) {
warnx(_("unexpected number of arguments"));
errtryhelp(EXIT_FAILURE);
}
if (all)
rc = fstrim_all(&range, verbose);
else {
rc = fstrim_filesystem(path, &range, verbose);
if (rc == 1) {
warnx(_("%s: the discard operation is not supported"), path);
rc = EXIT_FAILURE;
}
}
return rc;
}
