diff options
| -rw-r--r-- | .gitignore | 1 | ||||
| -rw-r--r-- | sys-utils/Makemodule.am | 5 | ||||
| -rw-r--r-- | sys-utils/blkdiscard.8 | 66 | ||||
| -rw-r--r-- | sys-utils/blkdiscard.c | 173 |
4 files changed, 245 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore index 5be008f58..a777d16ea 100644 --- a/.gitignore +++ b/.gitignore @@ -96,6 +96,7 @@ tests/run.sh.trs /fsck.minix /fsfreeze /fstrim +/blkdiscard /getopt /hexdump /hwclock diff --git a/sys-utils/Makemodule.am b/sys-utils/Makemodule.am index d376f04a4..a6e3c0768 100644 --- a/sys-utils/Makemodule.am +++ b/sys-utils/Makemodule.am @@ -54,6 +54,11 @@ dist_man_MANS += sys-utils/fstrim.8 fstrim_SOURCES = sys-utils/fstrim.c fstrim_LDADD = $(LDADD) libcommon.la +sbin_PROGRAMS += blkdiscard +dist_man_MANS += sys-utils/blkdiscard.8 +blkdiscard_SOURCES = sys-utils/blkdiscard.c +blkdiscard_LDADD = $(LDADD) libcommon.la + usrbin_exec_PROGRAMS += cytune dist_man_MANS += sys-utils/cytune.8 cytune_SOURCES = sys-utils/cytune.c sys-utils/cyclades.h diff --git a/sys-utils/blkdiscard.8 b/sys-utils/blkdiscard.8 new file mode 100644 index 000000000..fcc38f6d2 --- /dev/null +++ b/sys-utils/blkdiscard.8 @@ -0,0 +1,66 @@ +.\" -*- nroff -*- +.TH BLKDISCARD 8 "September 2012" "util-linux" "System Administration" +.SH NAME +blkdiscard \- discard sectors on a device +.SH SYNOPSIS +.B blkdiscard +.RB [ \-o +.IR offset ] +.RB [ \-l +.IR length ] +.RB [ \-s ] +.RB [ \-v ] +.I device + +.SH DESCRIPTION +.B blkdiscard +is used to discard device sectors. This is useful for solid-state +drivers (SSDs) and thinly-provisioned storage. Unlike +.BR fstrim (8) +this command is used directly on the block device. +.PP +By default, +.B blkdiscard +will discard all blocks on the device. Options may be used to +modify this behavior based on range or size, as explained below. +.PP +The +.I device +argument is the pathname of the block device. + +.B WARNING: All data in the discarded region on the device will be lost! + +.SH OPTIONS +The \fIoffset\fR and \fIlength\fR arguments may be +followed by the multiplicative suffixes KiB=1024, MiB=1024*1024, and so on for +GiB, TiB, PiB, EiB, ZiB and YiB (the "iB" is optional, e.g. "K" has the same +meaning as "KiB") or the suffixes KB=1000, MB=1000*1000, and so on for GB, PB, +EB, ZB and YB. +.IP "\fB\-h, \-\-help\fP" +Print help and exit. +.IP "\fB\-o, \-\-offset\fP \fIoffset\fP" +Byte offset in the device from which to discard. Provided value will be +aligned to the device sector size. Default value is zero. +.IP "\fB\-l, \-\-length\fP \fIlength\fP" +Number of bytes after starting point to discard. Provided value will be +aligned to the device sector size. If the specified value extends past the +end of the device, +.B blkdiscard +will stop at the device size boundary. Default value extends to the end +of the device. +.IP "\fB\-s, \-\-secure\fP" +Perform secure discard. Secure discard is the same as regular discard except +all copies of the discarded blocks possibly created by garbage collection must +also be erased. It has to be supported by the device. +.IP "\fB\-v, \-\-verbose\fP" +Print aligned \fIoffset\fR and \fIlength\fR arguments. + +.SH AUTHOR +.nf +Lukas Czerner <lczerner@redhat.com> +.fi +.SH SEE ALSO +.BR fstrim (8) +.SH AVAILABILITY +The blkdiscard command is part of the util-linux package and is available +from ftp://ftp.kernel.org/pub/linux/utils/util-linux/. diff --git a/sys-utils/blkdiscard.c b/sys-utils/blkdiscard.c new file mode 100644 index 000000000..bdcd06e37 --- /dev/null +++ b/sys-utils/blkdiscard.c @@ -0,0 +1,173 @@ +/* + * blkdiscard.c -- discard the part (or whole) of the block device. + * + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Written by Lukas Czerner <lczerner@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 BLKDISCARD ioctl to discard part or the whole block + * device if the device supports it. You can specify range (start and + * length) to be discarded, or simply discard the whole device. + */ + + +#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" + +#ifndef BLKDISCARD +#define BLKDISCARD _IO(0x12,119) +#endif + +#ifndef BLKSECDISCARD +#define BLKSECDISCARD _IO(0x12,125) +#endif + +static void __attribute__((__noreturn__)) usage(FILE *out) +{ + fputs(USAGE_HEADER, out); + fprintf(out, + _(" %s [options] <device>\n"), program_invocation_short_name); + fputs(USAGE_OPTIONS, out); + fputs(_(" -o, --offset <num> offset in bytes to discard from\n" + " -l, --length <num> length of bytes to discard from the offset\n" + " -s, --secure perform secure discard\n" + " -v, --verbose print aligned length and offset\n"), + out); + fputs(USAGE_SEPARATOR, out); + fputs(USAGE_HELP, out); + fputs(USAGE_VERSION, out); + fprintf(out, USAGE_MAN_TAIL("blkdiscard(8)")); + exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS); +} + +int main(int argc, char **argv) +{ + char *path; + int c, fd, verbose = 0, secure = 0; + uint64_t end, blksize, secsize, range[2]; + struct stat sb; + + static const struct option longopts[] = { + { "help", 0, 0, 'h' }, + { "version", 0, 0, 'V' }, + { "offset", 1, 0, 'o' }, + { "length", 1, 0, 'l' }, + { "secure", 0, 0, 's' }, + { "verbose", 0, 0, 'v' }, + { NULL, 0, 0, 0 } + }; + + setlocale(LC_ALL, ""); + bindtextdomain(PACKAGE, LOCALEDIR); + textdomain(PACKAGE); + atexit(close_stdout); + + range[0] = 0; + range[1] = ULLONG_MAX; + + while ((c = getopt_long(argc, argv, "hVsvo:l:", longopts, NULL)) != -1) { + switch(c) { + case 'h': + usage(stdout); + break; + case 'V': + printf(UTIL_LINUX_VERSION); + return EXIT_SUCCESS; + case 'l': + range[1] = strtosize_or_err(optarg, + _("failed to parse length")); + break; + case 'o': + range[0] = strtosize_or_err(optarg, + _("failed to parse offset")); + break; + case 's': + secure = 1; + break; + case 'v': + verbose = 1; + break; + default: + usage(stderr); + break; + } + } + + if (optind == argc) + errx(EXIT_FAILURE, _("no device specified.")); + + path = argv[optind++]; + + if (optind != argc) { + warnx(_("unexpected number of arguments")); + usage(stderr); + } + + if (stat(path, &sb) == -1) + err(EXIT_FAILURE, _("stat failed %s"), path); + if (!S_ISBLK(sb.st_mode)) + errx(EXIT_FAILURE, _("%s: not a block device"), path); + + fd = open(path, O_WRONLY); + if (fd < 0) + err(EXIT_FAILURE, _("cannot open %s"), path); + + if (ioctl(fd, BLKGETSIZE64, &blksize)) + err(EXIT_FAILURE, _("%s: BLKGETSIZE64 ioctl failed"), path); + + if (ioctl(fd, BLKSSZGET, &secsize)) + err(EXIT_FAILURE, _("%s: BLKSSZGET ioctl failed"), path); + + /* align range to the sector size */ + range[0] = (range[0] + secsize - 1) & ~(secsize - 1); + range[1] &= ~(secsize - 1); + + /* is the range end behind the end of the device ?*/ + end = range[0] + range[1]; + if (end < range[0] || end > blksize) + range[1] = blksize - range[0]; + + if (secure) { + if (ioctl(fd, BLKSECDISCARD, &range)) + err(EXIT_FAILURE, _("%s: BLKSECDISCARD ioctl failed"), path); + } else { + if (ioctl(fd, BLKDISCARD, &range)) + err(EXIT_FAILURE, _("%s: BLKDISCARD ioctl failed"), path); + } + + if (verbose) + /* TRANSLATORS: The standard value here is a very large number. */ + printf(_("%s: Discarded %" PRIu64 " bytes from the " + "offset %" PRIu64"\n"), path, + (uint64_t) range[1], (uint64_t) range[0]); + + close(fd); + return EXIT_SUCCESS; +} |