On Wed, 12 Sep 2012, Lukas Czerner wrote: > Date: Wed, 12 Sep 2012 17:49:15 -0400 > From: Lukas Czerner <lczerner@xxxxxxxxxx> > To: util-linux@xxxxxxxxxxxxxxx, kzak@xxxxxxxxxx > Cc: Lukas Czerner <lczerner@xxxxxxxxxx> > Subject: [PATCH] blkdiscard: add new command > > blkdiscard is used to discard device sectors. This is useful for > solid-state drivers (SSDs) and thinly-provisioned storage. Unlike > fstrim this command is used directly on the block device. > > blkkdiscard uses BLKDISCARD ioctl or BLKSECDISCARD ioctl for the secure > discard. > > All data in the discarded region on the device will be lost! Hi Karel, any progress here ? Thanks! -Lukas > > Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx> > --- > .gitignore | 1 + > sys-utils/Makemodule.am | 5 ++ > sys-utils/blkdiscard.8 | 66 ++++++++++++++++++ > sys-utils/blkdiscard.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 245 insertions(+), 0 deletions(-) > create mode 100644 sys-utils/blkdiscard.8 > create mode 100644 sys-utils/blkdiscard.c > > diff --git a/.gitignore b/.gitignore > index 5be008f..a777d16 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 d376f04..a6e3c07 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 0000000..fcc38f6 > --- /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@xxxxxxxxxx> > +.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 0000000..bdcd06e > --- /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@xxxxxxxxxx> > + * > + * 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; > +} > -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
