[src/trunk]: src/sbin/blkdiscard convert my fdiscard-stuff.c into blkdiscard....

[mrg <mrg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/dd4901dd8d1d
branches:  trunk
changeset: 360000:dd4901dd8d1d
user:      mrg <mrg%NetBSD.org@localhost>
date:      Mon Feb 07 09:33:26 2022 +0000

description:
convert my fdiscard-stuff.c into blkdiscard.c and give it a UI
that matches the linux-util version.

comes in two forms:  blkdiscard equivalent, and the (almost)
original interface i used (the "-s" option is conflicting and
i've switched to only the not yet implemented secure erase
option.)  the only real difference is that "fdiscard" mode
requires the -R flag to do something, vs blkdiscard needs the
-n flag to not do anything.


not yet hooked into the build or sets.  would like more testing
on it to be performed before doing that (but soon.)

diffstat:

 sbin/blkdiscard/Makefile     |    9 +
 sbin/blkdiscard/blkdiscard.8 |  163 ++++++++++++++++++++++++++
 sbin/blkdiscard/blkdiscard.c |  264 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 436 insertions(+), 0 deletions(-)

diffs (truncated from 448 to 300 lines):

diff -r 7ec3ccb259a8 -r dd4901dd8d1d sbin/blkdiscard/Makefile
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sbin/blkdiscard/Makefile  Mon Feb 07 09:33:26 2022 +0000
@@ -0,0 +1,9 @@
+#      $NetBSD: Makefile,v 1.1 2022/02/07 09:33:26 mrg Exp $
+
+PROG=  blkdiscard
+MAN=   blkdiscard.8
+
+LINKS= ${BINDIR}/blkdiscard ${BINDIR}/fdiscard
+MLINKS=        blkdiscard.8 fdiscard.8
+
+.include <bsd.prog.mk>
diff -r 7ec3ccb259a8 -r dd4901dd8d1d sbin/blkdiscard/blkdiscard.8
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sbin/blkdiscard/blkdiscard.8      Mon Feb 07 09:33:26 2022 +0000
@@ -0,0 +1,163 @@
+.\"    $NetBSD: blkdiscard.8,v 1.1 2022/02/07 09:33:26 mrg Exp $
+.\"
+.\" Copyright (c) 2022 Matthew R. Green
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.Dd February 6, 2022
+.Dt BLKDISCARD 8
+.Os
+.Sh NAME
+.Nm blkdiscard
+.Nd tool to discard portions of a device or file
+.Sh SYNOPSIS
+.Nm
+.Op Fl h
+.Op Fl l Ar length
+.Op Fl p Ar chunksize
+.Op Fl n
+.Op Fl o Ar firstbyte
+.Op Fl R
+.Op Fl s
+.Op Fl V
+.Op Fl v
+.Op Fl z
+.Ar file
+.Nm fdiscard
+.Op Fl f Ar firstbyte
+.Op Fl h
+.Op Fl l Ar length
+.Op Fl m Ar chunksize
+.Op Fl n
+.Op Fl R
+.Op Fl s
+.Op Fl V
+.Op Fl v
+.Op Fl z
+.Ar file
+.Sh DESCRIPTION
+The
+.Nm
+program can be used to discard portions of storage, and works on either
+device files directly or upon files inside of a mounted file-system.
+It provides access to the
+.Xr fdiscard 2
+system call, and relies upon the
+backing device to have support in both the
+.Nm
+driver and in the hardware itself.
+.Pp
+The
+.Nm fdiscard
+interface defaults to the
+.Dq no-run
+mode and requires the
+.Fl R
+option to perform any actions.
+.Pp
+.Sh OPTIONS
+Available options:
+.Bl -tag -width chunksize123
+.It Fl f Ar firstbyte
+Set the first byte to be discarded.
+The default is 0.
+.It Fl h
+Display built-in help.
+.It Fl l Ar length
+Limit the length to be discarded.
+The default is the full device or file size, or the rest of the device
+or file when the start offset has been set.
+.It Fl m Ar chunksize
+Set the per-operation chunksize.
+The default is 32 MiB.
+.It Fl n
+Set the
+.Dq no-run
+option, and do not actually call
+.Xr fdiscard 2 ,
+secure erase, or write zeroes to the file.
+.It Fl o Ar firstbyte
+This flag is an alias for the
+.Fl f
+flag.
+.It Fl p Ar chunksize
+This flag is an alias for the
+.Fl m
+flag.
+.It Fl R
+Turn off the
+.Dq no-run mode.
+.It Fl s
+Use secure erase operation.
+This requires specific hardware support and is not currently supported.
+.It Fl V
+Display the program version and exit.
+.It Fl v
+Set the verbose flag.
+.It Fl z
+Write zeroes instead of calling
+.Xr fdiscard 2 .
+.Sh EXAMPLES
+To have a dry-run cleaning of any particular file or device:
+.Bd -literal -offset indent
+# blkdiscard -n -v filename
+# blkdiscard -n -v /dev/rwd0b
+.Ed
+.Pp
+To discard all the blocks on a swap device:
+.Bd -literal -offset indent
+# blkdiscard -v /dev/rwd0b
+.Ed
+.Pp
+To discard all but the first 256MiB of a device, using 128MiB increments:
+.Bd -literal -offset indent
+# blkdiscard -v -f 256m -m 128m /dev/rwd0c
+.Ed
+.Pp
+To zero out the contents of a file or device:
+.Bd -literal -offset indent
+# blkdiscard -v -z filename
+# blkdiscard -v -z /dev/device
+.Ed
+.Sh SEE ALSO
+.Xr fdiscard 2
+.Sh HISTORY
+The
+.Nm
+command first appeared linux-util.
+This implementation was originally called fdiscard-stuff and has been
+converted to be
+.Lx
+.Xr blkdiscard 8
+compatible and appeared in
+.Nx 10.0 .
+.Sh AUTHORS
+The
+.Nm
+command was written by
+.An Matthew R. Green
+.Aq mrg%eterna.com.au@localhost .
+.Sh BUGS
+The secure erase funtionality of the
+.Fl s
+option is not yet implemented.
diff -r 7ec3ccb259a8 -r dd4901dd8d1d sbin/blkdiscard/blkdiscard.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sbin/blkdiscard/blkdiscard.c      Mon Feb 07 09:33:26 2022 +0000
@@ -0,0 +1,264 @@
+/*     $NetBSD: blkdiscard.c,v 1.1 2022/02/07 09:33:26 mrg Exp $       */
+
+/*
+ * Copyright (c) 2019, 2020, 2022 Matthew R. Green
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/* from: $eterna: fdiscard-stuff.c,v 1.3 2020/12/25 23:40:19 mrg Exp $ */
+
+/* fdiscard(2) front-end -- TRIM support. */
+
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/disk.h>
+#include <sys/disklabel.h>
+#include <sys/ioctl.h>
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <err.h>
+#include <errno.h>
+#include <assert.h>
+#include <stdbool.h>
+
+static bool secure = false;
+static bool zeroout = false;
+static char *zeros = NULL;
+
+#define FDISCARD_VERSION       20220206u
+
+static void __dead
+usage(const char* msg)
+{
+       FILE *out = stdout;
+       int rv = 0;
+
+       if (msg) {
+               out = stderr;
+               rv = 1;
+               fprintf(out, "%s", msg);
+       }
+       fprintf(out, "Usage: blkdiscard [-hnRsVvz] [-l length] "
+                    "[-m chunk_bytes]\n"
+                    "                  [-o first_byte] <file>\n");
+       exit(rv);
+}
+
+static void __dead
+version(void)
+{
+
+       printf("NetBSD blkdiscard %u\n", FDISCARD_VERSION);
+       exit(0);
+}
+
+static void
+write_one(int fd, off_t discard_size, off_t first_byte)
+{
+
+       if (secure)
+               /* not yet */;
+       else if (zeroout) {
+               if (pwrite(fd, zeros, discard_size, first_byte) != discard_size)
+                       err(1, "pwrite");
+       } else if (fdiscard(fd, first_byte, discard_size) != 0)
+               err(1, "fdiscard");
+}
+
+int
+main(int argc, char *argv[])
+{
+       off_t first_byte = 0, end_offset = 0;
+       /* doing a terabyte at a time leads to ATA timeout issues */
+       off_t max_per_call = 32 * 1024 * 1024;
+       off_t discard_size;
+       off_t size = 0;
+       off_t length = 0;
+       int64_t val;
+       int i;
+       bool verbose = false;
+
+       /* Default /sbin/blkdiscard to be "run" */
+       bool norun = strcmp(getprogname(), "blkdiscard") != 0;
+
+       while ((i = getopt(argc, argv, "f:hl:m:no:p:RsvVz")) != -1) {
+               switch (i) {
+               case 'l':
+                       if (dehumanize_number(optarg, &val) == -1 || val < 0)
+                               usage("bad -s\n");
+                       length = val;