diff options
Diffstat (limited to 'sys-utils/fstrim.c')
-rw-r--r-- | sys-utils/fstrim.c | 417 |
1 files changed, 417 insertions, 0 deletions
diff --git a/sys-utils/fstrim.c b/sys-utils/fstrim.c new file mode 100644 index 0000000..2a67892 --- /dev/null +++ b/sys-utils/fstrim.c @@ -0,0 +1,417 @@ +/* + * 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, + 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, rc; + struct stat sb; + struct fstrim_range range; + + /* kernel modifies the range */ + memcpy(&range, &ctl->range, 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; + } + + 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)) { + rc = errno == EOPNOTSUPP || errno == ENOTTY ? 1 : -errno; + + if (rc != 1) + 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); + 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; + + 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"); + + ul_unref_path(pc); + return rc == 0 && dg > 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(); + + itr = mnt_new_iter(MNT_ITER_BACKWARD); + if (!itr) + err(MNT_EX_FAIL, _("failed to initialize libmount iterator")); + + 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); + + /* de-duplicate by source */ + mnt_table_uniq_fs(tab, MNT_UNIQ_FORWARD, uniq_fs_source_cmp); + + if (ctl->fstab) { + cache = mnt_new_cache(); + if (!cache) + err(MNT_EX_FAIL, _("failed to initialize libmount cache")); + } + + 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 (!tgt || mnt_fs_is_pseudofs(fs) || mnt_fs_is_netfs(fs)) + continue; + + if (!src && cache) { + /* convert LABEL= (etc.) from fstab to paths */ + const char *spec = mnt_fs_get_source(fs); + + if (!spec) + continue; + src = mnt_resolve_spec(spec, cache); + } + + if (!src || *src != '/') + 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(ctl, tgt, src) < 0) + cnt_err++; + } + + ul_unref_path(wholedisk); + mnt_unref_table(tab); + mnt_free_iter(itr); + 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(_(" -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 } + }; + + 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' }, + { "dry-run", no_argument, NULL, 'n' }, + { NULL, 0, NULL, 0 } + }; + + setlocale(LC_ALL, ""); + bindtextdomain(PACKAGE, LOCALEDIR); + textdomain(PACKAGE); + atexit(close_stdout); + + 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 'h': + usage(); + break; + case 'V': + printf(UTIL_LINUX_VERSION); + return EXIT_SUCCESS; + 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; + 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) + return fstrim_all(&ctl); /* MNT_EX_* codes */ + + rc = fstrim_filesystem(&ctl, path, NULL); + if (rc == 1) + warnx(_("%s: the discard operation is not supported"), path); + + return rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE; +} |