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Diffstat (limited to '')
-rw-r--r-- | sys-utils/fstrim.c | 547 |
1 files changed, 547 insertions, 0 deletions
diff --git a/sys-utils/fstrim.c b/sys-utils/fstrim.c new file mode 100644 index 0000000..fef33b0 --- /dev/null +++ b/sys-utils/fstrim.c @@ -0,0 +1,547 @@ +/* + * 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 "xalloc.h" +#include "strutils.h" +#include "c.h" +#include "closestream.h" +#include "pathnames.h" +#include "sysfs.h" +#include "optutils.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_unsupp : 1, + dryrun : 1; +}; + +static int is_directory(const char *path, int silent) +{ + struct stat sb; + + if (stat(path, &sb) == -1) { + if (!silent) + warn(_("stat of %s failed"), path); + return 0; + } + if (!S_ISDIR(sb.st_mode)) { + if (!silent) + warnx(_("%s: not a directory"), path); + return 0; + } + return 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 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 (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)); +} + +/* + * -1 = tab empty + * 0 = all success + * 32 = all failed + * 64 = some failed, some success + */ +static int fstrim_all_from_file(struct fstrim_control *ctl, const char *filename) +{ + 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; + int fstab = 0; + + tab = mnt_new_table_from_file(filename); + if (!tab) + err(MNT_EX_FAIL, _("failed to parse %s"), filename); + + if (mnt_table_is_empty(tab)) { + mnt_unref_table(tab); + return -1; + } + + if (streq_paths(filename, "/etc/fstab")) + fstab = 1; + + /* de-duplicate by mountpoints */ + mnt_table_uniq_fs(tab, 0, uniq_fs_target_cmp); + + if (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(tgt, W_OK) != 0) { + if (errno == EROFS) + continue; + if (errno == EACCES) + continue; + } + + if (!is_directory(tgt, 1) || + !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_unsupp) + 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; +} + +/* + * 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, const char *tabs) +{ + char *list = xstrdup(tabs); + char *file; + int rc = MNT_EX_FAIL; + + mnt_init_debug(0); + ul_path_init_debug(); + + for (file = strtok(list, ":"); file; file = strtok(NULL, ":")) { + struct stat st; + + if (stat(file, &st) < 0 || !S_ISREG(st.st_mode)) + continue; + + rc = fstrim_all_from_file(ctl, file); + if (rc >= 0) + break; /* stop after first non-empty file */ + } + free(list); + return rc; +} + +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 mounted filesystems\n"), out); + fputs(_(" -A, --fstab trim filesystems from /etc/fstab\n"), out); + fputs(_(" -I, --listed-in <list> trim filesystems listed in specified files\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-unsupported suppress error messages if trim unsupported\n"), out); + fputs(_(" -n, --dry-run does everything, but trim\n"), out); + + fputs(USAGE_SEPARATOR, out); + printf(USAGE_HELP_OPTIONS(21)); + + fputs(USAGE_ARGUMENTS, out); + printf(USAGE_ARG_SIZE(_("<num>"))); + + printf(USAGE_MAN_TAIL("fstrim(8)")); + exit(EXIT_SUCCESS); +} + +int main(int argc, char **argv) +{ + char *path = NULL; + char *tabs = NULL; + int c, rc, all = 0; + struct fstrim_control ctl = { + .range = { .len = ULLONG_MAX } + }; + enum { + OPT_QUIET_UNSUPP = CHAR_MAX + 1 + }; + + static const struct option longopts[] = { + { "all", no_argument, NULL, 'a' }, + { "fstab", no_argument, NULL, 'A' }, + { "help", no_argument, NULL, 'h' }, + { "listed-in", required_argument, NULL, 'I' }, + { "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-unsupported", no_argument, NULL, OPT_QUIET_UNSUPP }, + { "dry-run", no_argument, NULL, 'n' }, + { NULL, 0, NULL, 0 } + }; + + static const ul_excl_t excl[] = { /* rows and cols in ASCII order */ + { 'A','I','a' }, + { 0 } + }; + int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT; + + setlocale(LC_ALL, ""); + bindtextdomain(PACKAGE, LOCALEDIR); + textdomain(PACKAGE); + close_stdout_atexit(); + + while ((c = getopt_long(argc, argv, "AahI:l:m:no:Vv", longopts, NULL)) != -1) { + + err_exclusive_options(c, longopts, excl, excl_st); + + switch(c) { + case 'A': + all = 1; + tabs = _PATH_MNTTAB; /* fstab */ + break; + case 'a': + all = 1; + tabs = _PATH_PROC_MOUNTINFO; /* mountinfo */ + break; + case 'I': + all = 1; + tabs = optarg; + 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_UNSUPP: + ctl.quiet_unsupp = 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, tabs); /* MNT_EX_* codes */ + + if (!is_directory(path, 0)) + return EXIT_FAILURE; + + rc = fstrim_filesystem(&ctl, path, NULL); + if (rc == 1 && !ctl.quiet_unsupp) + warnx(_("%s: the discard operation is not supported"), path); + + return rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE; +} |