1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158
|
/* libguestfs - the guestfsd daemon
* Copyright (C) 2009 Red Hat Inc.
*
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <inttypes.h>
#include <unistd.h>
#include "daemon.h"
#include "actions.h"
/* These functions are all about using the blockdev command, so
* we centralize it in one call.
*/
static int64_t
call_blockdev (const char *device, const char *switc, int extraarg, int prints)
{
int r;
int64_t rv;
char *out, *err;
const char *argv[] = {
"blockdev",
switc,
NULL,
NULL,
NULL
};
char buf[64];
/* When you call close on any block device, udev kicks off a rule
* which runs blkid to reexamine the device. We need to wait for
* this rule to finish running (from a previous operation) since it
* holds the device open and can cause other operations to fail,
* notably BLKRRPART.
*
* This is particularly a problem where we have just written to a
* device (eg. zeroing it) and immediately call blockdev --rereadpt.
*
* Therefore, wait for udev to finish all outstanding events before
* performing any blockdev command.
*/
udev_settle ();
if (extraarg > 0) {
snprintf (buf, sizeof buf, "%d", extraarg);
argv[2] = buf;
argv[3] = device;
} else
argv[2] = device;
r = commandv (&out, &err, argv);
if (r == -1) {
reply_with_error ("%s: %s", argv[0], err);
free (err);
free (out);
return -1;
}
rv = 0;
if (prints) {
if (sscanf (out, "%" SCNi64, &rv) != 1) {
reply_with_error ("%s: expected output, but got nothing", argv[0]);
free (out);
free (err);
return -1;
}
}
free (out);
free (err);
return rv;
}
int
do_blockdev_setro (const char *device)
{
return (int) call_blockdev (device, "--setro", 0, 0);
}
int
do_blockdev_setrw (const char *device)
{
return (int) call_blockdev (device, "--setrw", 0, 0);
}
int
do_blockdev_getro (const char *device)
{
return (int) call_blockdev (device, "--getro", 0, 1);
}
int
do_blockdev_getss (const char *device)
{
return (int) call_blockdev (device, "--getss", 0, 1);
}
int
do_blockdev_getbsz (const char *device)
{
return (int) call_blockdev (device, "--getbsz", 0, 1);
}
int
do_blockdev_setbsz (const char *device, int blocksize)
{
if (blocksize <= 0 /* || blocksize >= what? */) {
reply_with_error ("blocksize must be > 0");
return -1;
}
return (int) call_blockdev (device, "--setbsz", blocksize, 0);
}
int64_t
do_blockdev_getsz (const char *device)
{
return call_blockdev (device, "--getsz", 0, 1);
}
int64_t
do_blockdev_getsize64 (const char *device)
{
return call_blockdev (device, "--getsize64", 0, 1);
}
int
do_blockdev_flushbufs (const char *device)
{
return call_blockdev (device, "--flushbufs", 0, 0);
}
int
do_blockdev_rereadpt (const char *device)
{
return call_blockdev (device, "--rereadpt", 0, 0);
}
|