/*
* 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 <linux/fs.h>
#include "nls.h"
#include "strutils.h"
#include "c.h"
#include "closestream.h"
#include "pathnames.h"
#include "sysfs.h"
#include <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
struct fstrim_control {
struct fstrim_range range;
unsigned int verbose : 1,
quiet : 1,
fstab : 1,
dryrun : 1;
};
/* returns: 0 = success, 1 = unsupported, < 0 = error */
static int fstrim_filesystem(struct fstrim_control *ctl, const char *path, const char *devname)
{
int fd = -1, rc;
struct stat sb;
struct fstrim_range range;
char *rpath = realpath(path, NULL);
if (!rpath) {
warn(_("cannot get realpath: %s"), path);
rc = -errno;
goto done;
}
/* kernel modifies the range */
memcpy(&range, &ctl->range, sizeof(range));
fd = open(rpath, 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;
}
if (ctl->dryrun) {
if (devname)
printf(_("%s: 0 B (dry run) trimmed on %s\n"), path, devname);
else
printf(_("%s: 0 B (dry run) trimmed\n"), path);
rc = 0;
goto done;
}
errno = 0;
if (ioctl(fd, FITRIM, &range)) {
switch (errno) {
case EBADF:
case ENOTTY:
case EOPNOTSUPP:
rc = 1;
break;
default:
rc = -errno;
}
if (rc < 0)
warn(_("%s: FITRIM ioctl failed"), path);
goto done;
}
if (ctl->verbose) {
char *str = size_to_human_string(
SIZE_SUFFIX_3LETTER | SIZE_SUFFIX_SPACE,
(uint64_t) range.len);
if (devname)
/* TRANSLATORS: The standard value here is a very large number. */
printf(_("%s: %s (%" PRIu64 " bytes) trimmed on %s\n"),
path, str, (uint64_t) range.len, devname);
else
/* 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);
free(rpath);
return rc;
}
static int has_discard(const char *devname, struct path_cxt **wholedisk)
{
struct path_cxt *pc = NULL;
uint64_t dg = 0;
dev_t disk = 0, dev;
int rc = -1, rdonly = 0;
dev = sysfs_devname_to_devno(devname);
if (!dev)
goto fail;
pc = ul_new_sysfs_path(dev, NULL, NULL);
if (!pc)
goto fail;
/*
* 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).
*/
rc = sysfs_blkdev_get_wholedisk(pc, NULL, 0, &disk);
if (rc != 0 || !disk)
goto fail;
if (dev != disk) {
/* Partition, try reuse whole-disk context if valid for the
* current device, otherwise create new context for the
* whole-disk.
*/
if (*wholedisk && sysfs_blkdev_get_devno(*wholedisk) != disk) {
ul_unref_path(*wholedisk);
*wholedisk = NULL;
}
if (!*wholedisk) {
*wholedisk = ul_new_sysfs_path(disk, NULL, NULL);
if (!*wholedisk)
goto fail;
}
sysfs_blkdev_set_parent(pc, *wholedisk);
}
rc = ul_path_read_u64(pc, &dg, "queue/discard_granularity");
if (!rc)
ul_path_scanf(pc, "ro", "%d", &rdonly);
ul_unref_path(pc);
return rc == 0 && dg > 0 && rdonly == 0;
fail:
ul_unref_path(pc);
return 1;
}
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_control *ctl)
{
struct libmnt_fs *fs;
struct libmnt_iter *itr;
struct libmnt_table *tab;
struct libmnt_cache *cache = NULL;
struct path_cxt *wholedisk = NULL;
int cnt = 0, cnt_err = 0;
const char *filename = _PATH_PROC_MOUNTINFO;
mnt_init_debug(0);
ul_path_init_debug();
if (ctl->fstab)
filename = mnt_get_fstab_path();
tab = mnt_new_table_from_file(filename);
if (!tab)
err(MNT_EX_FAIL, _("failed to parse %s"), filename);
/* de-duplicate by mountpoints */
mnt_table_uniq_fs(tab, 0, uniq_fs_target_cmp);
if (ctl->fstab) {
char *rootdev = NULL;
cache = mnt_new_cache();
if (!cache)
err(MNT_EX_FAIL, _("failed to initialize libmount cache"));
/* Make sure we trim also root FS on --fstab */
if (mnt_table_find_target(tab, "/", MNT_ITER_FORWARD) == NULL &&
mnt_guess_system_root(0, cache, &rootdev) == 0) {
fs = mnt_new_fs();
if (!fs)
err(MNT_EX_FAIL, _("failed to allocate FS handler"));
mnt_fs_set_target(fs, "/");
mnt_fs_set_source(fs, rootdev);
mnt_fs_set_fstype(fs, "auto");
mnt_table_add_fs(tab, fs);
mnt_unref_fs(fs);
fs = NULL;
}
}
itr = mnt_new_iter(MNT_ITER_BACKWARD);
if (!itr)
err(MNT_EX_FAIL, _("failed to initialize libmount iterator"));
/* Remove useless entries and canonicalize the table */
while (mnt_table_next_fs(tab, itr, &fs) == 0) {
const char *src = mnt_fs_get_srcpath(fs),
*tgt = mnt_fs_get_target(fs);
if (!tgt || mnt_fs_is_pseudofs(fs) || mnt_fs_is_netfs(fs)) {
mnt_table_remove_fs(tab, fs);
continue;
}
/* convert LABEL= (etc.) from fstab to paths */
if (!src && cache) {
const char *spec = mnt_fs_get_source(fs);
if (!spec) {
mnt_table_remove_fs(tab, fs);
continue;
}
src = mnt_resolve_spec(spec, cache);
mnt_fs_set_source(fs, src);
}
if (!src || *src != '/') {
mnt_table_remove_fs(tab, fs);
continue;
}
}
/* de-duplicate by source */
mnt_table_uniq_fs(tab, MNT_UNIQ_FORWARD, uniq_fs_source_cmp);
mnt_reset_iter(itr, MNT_ITER_BACKWARD);
/* Do FITRIM */
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;
/* 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 */
/* FITRIM on read-only filesystem can fail, and it can fail */
if (access(path, W_OK) != 0) {
if (errno == EROFS)
continue;
if (errno == EACCES)
continue;
}
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 LUKS (by default) does not support FSTRIM.
*
* This is reason why we ignore EOPNOTSUPP and ENOTTY errors
* from discard ioctl.
*/
rc = fstrim_filesystem(ctl, tgt, src);
if (rc < 0)
cnt_err++;
else if (rc == 1 && !ctl->quiet)
warnx(_("%s: the discard operation is not supported"), tgt);
}
mnt_free_iter(itr);
ul_unref_path(wholedisk);
mnt_unref_table(tab);
mnt_unref_cache(cache);
if (cnt && cnt == cnt_err)
return MNT_EX_FAIL; /* all failed */
if (cnt && cnt_err)
return MNT_EX_SOMEOK; /* some ok */
return MNT_EX_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 supported mounted filesystems\n"), out);
fputs(_(" -A, --fstab trim all supported mounted filesystems from /etc/fstab\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(_(" --quiet suppress error messages\n"), out);
fputs(_(" -n, --dry-run does everything, but trim\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, all = 0;
struct fstrim_control ctl = {
.range = { .len = ULLONG_MAX }
};
enum {
OPT_QUIET = CHAR_MAX + 1
};
static const struct option longopts[] = {
{ "all", no_argument, NULL, 'a' },
{ "fstab", 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' },
{ "quiet", no_argument, NULL, OPT_QUIET },
{ "dry-run", no_argument, NULL, 'n' },
{ NULL, 0, NULL, 0 }
};
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
close_stdout_atexit();
while ((c = getopt_long(argc, argv, "Aahl:m:no:Vv", longopts, NULL)) != -1) {
switch(c) {
case 'A':
ctl.fstab = 1;
/* fallthrough */
case 'a':
all = 1;
break;
case 'n':
ctl.dryrun = 1;
break;
case 'l':
ctl.range.len = strtosize_or_err(optarg,
_("failed to parse length"));
break;
case 'o':
ctl.range.start = strtosize_or_err(optarg,
_("failed to parse offset"));
break;
case 'm':
ctl.range.minlen = strtosize_or_err(optarg,
_("failed to parse minimum extent length"));
break;
case 'v':
ctl.verbose = 1;
break;
case OPT_QUIET:
ctl.quiet = 1;
break;
case 'h':
usage();
case 'V':
print_version(EXIT_SUCCESS);
default:
errtryhelp(EXIT_FAILURE);
}
}
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)
return fstrim_all(&ctl); /* MNT_EX_* codes */
rc = fstrim_filesystem(&ctl, path, NULL);
if (rc == 1 && !ctl.quiet)
warnx(_("%s: the discard operation is not supported"), path);
return rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
}
