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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define ATRACE_TAG ATRACE_TAG_PACKAGE_MANAGER
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <linux/kdev_t.h>
#include <chrono>
#include <android-base/logging.h>
#include <android-base/stringprintf.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
#include <fs_mgr/file_wait.h>
#include <utils/Trace.h>
#include "Loop.h"
#include "VoldUtil.h"
#include "sehandle.h"
using namespace std::literals;
using android::base::StringPrintf;
using android::base::unique_fd;
static const char* kVoldPrefix = "vold:";
static constexpr size_t kLoopDeviceRetryAttempts = 3u;
int Loop::create(const std::string& target, std::string& out_device) {
unique_fd ctl_fd(open("/dev/loop-control", O_RDWR | O_CLOEXEC));
if (ctl_fd.get() == -1) {
PLOG(ERROR) << "Failed to open loop-control";
return -errno;
}
int num = ioctl(ctl_fd.get(), LOOP_CTL_GET_FREE);
if (num == -1) {
PLOG(ERROR) << "Failed LOOP_CTL_GET_FREE";
return -errno;
}
out_device = StringPrintf("/dev/block/loop%d", num);
unique_fd target_fd;
for (size_t i = 0; i != kLoopDeviceRetryAttempts; ++i) {
target_fd.reset(open(target.c_str(), O_RDWR | O_CLOEXEC));
if (target_fd.get() != -1) {
break;
}
usleep(50000);
}
if (target_fd.get() == -1) {
PLOG(ERROR) << "Failed to open " << target;
return -errno;
}
if (!android::fs_mgr::WaitForFile(out_device, 2s)) {
LOG(ERROR) << "Failed to find " << out_device;
return -ENOENT;
}
unique_fd device_fd(open(out_device.c_str(), O_RDWR | O_CLOEXEC));
if (device_fd.get() == -1) {
PLOG(ERROR) << "Failed to open " << out_device;
return -errno;
}
if (ioctl(device_fd.get(), LOOP_SET_FD, target_fd.get()) == -1) {
PLOG(ERROR) << "Failed to LOOP_SET_FD";
return -errno;
}
struct loop_info64 li;
memset(&li, 0, sizeof(li));
strlcpy((char*)li.lo_crypt_name, kVoldPrefix, LO_NAME_SIZE);
if (ioctl(device_fd.get(), LOOP_SET_STATUS64, &li) == -1) {
PLOG(ERROR) << "Failed to LOOP_SET_STATUS64";
return -errno;
}
return 0;
}
int Loop::destroyByDevice(const char* loopDevice) {
int device_fd;
device_fd = open(loopDevice, O_RDONLY | O_CLOEXEC);
if (device_fd < 0) {
PLOG(ERROR) << "Failed to open " << loopDevice;
return -1;
}
if (ioctl(device_fd, LOOP_CLR_FD, 0) < 0) {
PLOG(ERROR) << "Failed to destroy " << loopDevice;
close(device_fd);
return -1;
}
close(device_fd);
return 0;
}
int Loop::destroyAll() {
ATRACE_NAME("Loop::destroyAll");
std::string root = "/dev/block/";
auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(root.c_str()), closedir);
if (!dirp) {
PLOG(ERROR) << "Failed to opendir";
return -1;
}
// Poke through all devices looking for loops
struct dirent* de;
while ((de = readdir(dirp.get()))) {
auto test = std::string(de->d_name);
if (!android::base::StartsWith(test, "loop")) continue;
auto path = root + de->d_name;
unique_fd fd(open(path.c_str(), O_RDWR | O_CLOEXEC));
if (fd.get() == -1) {
if (errno != ENOENT) {
PLOG(WARNING) << "Failed to open " << path;
}
continue;
}
struct loop_info64 li;
if (ioctl(fd.get(), LOOP_GET_STATUS64, &li) < 0) {
if (errno != ENXIO) {
PLOG(WARNING) << "Failed to LOOP_GET_STATUS64 " << path;
}
continue;
}
auto id = std::string((char*)li.lo_crypt_name);
if (android::base::StartsWith(id, kVoldPrefix)) {
LOG(DEBUG) << "Tearing down stale loop device at " << path << " named " << id;
if (ioctl(fd.get(), LOOP_CLR_FD, 0) < 0) {
PLOG(WARNING) << "Failed to LOOP_CLR_FD " << path;
}
} else {
LOG(DEBUG) << "Found unmanaged loop device at " << path << " named " << id;
}
}
return 0;
}
int Loop::createImageFile(const char* file, unsigned long numSectors) {
unique_fd fd(open(file, O_CREAT | O_WRONLY | O_TRUNC | O_CLOEXEC, 0600));
if (fd.get() == -1) {
PLOG(ERROR) << "Failed to create image " << file;
return -errno;
}
if (fallocate(fd.get(), 0, 0, numSectors * 512) == -1) {
PLOG(WARNING) << "Failed to fallocate; falling back to ftruncate";
if (ftruncate(fd, numSectors * 512) == -1) {
PLOG(ERROR) << "Failed to ftruncate";
return -errno;
}
}
return 0;
}
int Loop::resizeImageFile(const char* file, unsigned long numSectors) {
int fd;
if ((fd = open(file, O_RDWR | O_CLOEXEC)) < 0) {
PLOG(ERROR) << "Failed to open " << file;
return -1;
}
LOG(DEBUG) << "Attempting to increase " << file << " to " << numSectors;
if (fallocate(fd, 0, 0, numSectors * 512)) {
if (errno == ENOSYS || errno == ENOTSUP) {
PLOG(WARNING) << "fallocate not found. Falling back to ftruncate.";
if (ftruncate(fd, numSectors * 512) < 0) {
PLOG(ERROR) << "Failed to ftruncate";
close(fd);
return -1;
}
} else {
PLOG(ERROR) << "Failed to fallocate";
close(fd);
return -1;
}
}
close(fd);
return 0;
}
|
