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
159
160
|
/* 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"
GUESTFSD_EXT_CMD(str_blockdev, blockdev);
/* 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[] = {
str_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);
}
|
