Checkpoint of better dynamic device support.
This is the first in a series of changes that are designed to
introduce better support for dynamic block devices.
It starts by defining a new Volume object which represents a storage
endpoint that knows how to mount, unmount, and format itself. This
could be a filesystem directly on a partition, or it could be an
emulated FUSE filesystem, an ASEC, or an OBB.
These new volumes can be "stacked" so that unmounting a volume will
also unmount any volumes stacked above it. Volumes that provide
shared storage can also be asked to present themselves (through bind
mounts) into user-specific mount areas.
This change also adds a Disk class which is created based on block
kernel netlink events. Instead of waiting for partition events from
the kernel, it uses gptfdisk to read partition details and creates
the relevant Volume objects.
Change-Id: I0e8bc1f8f9dcb24405f5e795c0658998e22ae2f7
diff --git a/Disk.cpp b/Disk.cpp
new file mode 100644
index 0000000..673827c
--- /dev/null
+++ b/Disk.cpp
@@ -0,0 +1,286 @@
+/*
+ * Copyright (C) 2015 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 LOG_TAG "Vold"
+
+#include "Disk.h"
+#include "PublicVolume.h"
+#include "Utils.h"
+#include "VolumeBase.h"
+
+#include <cutils/log.h>
+#include <diskconfig/diskconfig.h>
+#include <utils/file.h>
+#include <utils/stringprintf.h>
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mount.h>
+
+namespace android {
+namespace vold {
+
+static const char* kSgdiskPath = "/system/bin/sgdisk";
+static const char* kSgdiskToken = " \t\n";
+
+static const char* kSysfsMmcMaxMinors = "/sys/module/mmcblk/parameters/perdev_minors";
+
+static const unsigned int kMajorBlockScsi = 8;
+static const unsigned int kMajorBlockMmc = 179;
+
+static const char* kGptBasicData = "EBD0A0A2-B9E5-4433-87C0-68B6B72699C7";
+static const char* kGptAndroidMeta = "19A710A2-B3CA-11E4-B026-10604B889DCF";
+static const char* kGptAndroidExt = "193D1EA4-B3CA-11E4-B075-10604B889DCF";
+
+enum class Table {
+ kUnknown,
+ kMbr,
+ kGpt,
+};
+
+Disk::Disk(const std::string& eventPath, dev_t device) :
+ mDevice(device), mSize(-1) {
+ mId = StringPrintf("disk:%ud:%ud", major(device), minor(device));
+ mSysPath = StringPrintf("/sys/%s", eventPath.c_str());
+ mDevPath = StringPrintf("/dev/block/vold/%ud:%ud", major(device), minor(device));
+
+ CreateDeviceNode(mDevPath, mDevice);
+}
+
+Disk::~Disk() {
+ DestroyDeviceNode(mDevPath);
+}
+
+std::shared_ptr<VolumeBase> Disk::findVolume(const std::string& id) {
+ for (std::shared_ptr<VolumeBase>& v : mParts) {
+ if (!id.compare(v->getId())) {
+ return v;
+ }
+ }
+ return nullptr;
+}
+
+status_t Disk::readMetadata() {
+ mSize = -1;
+ mLabel = "";
+
+ {
+ std::string path(mSysPath + "/size");
+ std::string tmp;
+ if (!ReadFileToString(path, &tmp)) {
+ ALOGW("Failed to read size from %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+ mSize = strtoll(tmp.c_str(), nullptr, 10);
+ }
+
+ switch (major(mDevice)) {
+ case kMajorBlockScsi: {
+ std::string path(mSysPath + "/device/vendor");
+ std::string tmp;
+ if (!ReadFileToString(path, &tmp)) {
+ ALOGW("Failed to read vendor from %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+ mLabel = tmp;
+ break;
+ }
+ case kMajorBlockMmc: {
+ std::string path(mSysPath + "/device/manfid");
+ std::string tmp;
+ if (!ReadFileToString(path, &tmp)) {
+ ALOGW("Failed to read manufacturer from %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+ uint64_t manfid = strtoll(tmp.c_str(), nullptr, 16);
+ // Our goal here is to give the user a meaningful label, ideally
+ // matching whatever is silk-screened on the card. To reduce
+ // user confusion, this list doesn't contain white-label manfid.
+ switch (manfid) {
+ case 0x000003: mLabel = "SanDisk"; break;
+ case 0x00001b: mLabel = "Samsung"; break;
+ case 0x000028: mLabel = "Lexar"; break;
+ case 0x000074: mLabel = "Transcend"; break;
+ }
+ break;
+ }
+ default: {
+ ALOGW("Unsupported block major type %d", major(mDevice));
+ return -ENOTSUP;
+ }
+ }
+
+ return OK;
+}
+
+status_t Disk::readPartitions() {
+ int8_t maxMinors = getMaxMinors();
+ if (maxMinors < 0) {
+ return -ENOTSUP;
+ }
+
+ mParts.clear();
+
+ // Parse partition table
+ std::string path(kSgdiskPath);
+ path += " --android-dump ";
+ path += mDevPath;
+ FILE* fp = popen(path.c_str(), "r");
+ if (!fp) {
+ ALOGE("Failed to run %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+
+ char line[1024];
+ Table table = Table::kUnknown;
+ while (fgets(line, sizeof(line), fp) != nullptr) {
+ char* token = strtok(line, kSgdiskToken);
+ if (!strcmp(token, "DISK")) {
+ const char* type = strtok(nullptr, kSgdiskToken);
+ ALOGD("%s: found %s partition table", mId.c_str(), type);
+ if (!strcmp(type, "mbr")) {
+ table = Table::kMbr;
+ } else if (!strcmp(type, "gpt")) {
+ table = Table::kGpt;
+ }
+ } else if (!strcmp(token, "PART")) {
+ int i = strtol(strtok(nullptr, kSgdiskToken), nullptr, 10);
+ if (i <= 0 || i > maxMinors) {
+ ALOGW("%s: ignoring partition %d beyond max supported devices",
+ mId.c_str(), i);
+ continue;
+ }
+ dev_t partDevice = makedev(major(mDevice), minor(mDevice) + i);
+
+ VolumeBase* vol = nullptr;
+ if (table == Table::kMbr) {
+ const char* type = strtok(nullptr, kSgdiskToken);
+ ALOGD("%s: MBR partition %d type %s", mId.c_str(), i, type);
+
+ switch (strtol(type, nullptr, 16)) {
+ case 0x06: // FAT16
+ case 0x0b: // W95 FAT32 (LBA)
+ case 0x0c: // W95 FAT32 (LBA)
+ case 0x0e: // W95 FAT16 (LBA)
+ vol = new PublicVolume(partDevice);
+ break;
+ }
+ } else if (table == Table::kGpt) {
+ const char* typeGuid = strtok(nullptr, kSgdiskToken);
+ const char* partGuid = strtok(nullptr, kSgdiskToken);
+ ALOGD("%s: GPT partition %d type %s, GUID %s", mId.c_str(), i,
+ typeGuid, partGuid);
+
+ if (!strcasecmp(typeGuid, kGptBasicData)) {
+ vol = new PublicVolume(partDevice);
+ } else if (!strcasecmp(typeGuid, kGptAndroidExt)) {
+ //vol = new PrivateVolume();
+ }
+ }
+
+ if (vol != nullptr) {
+ mParts.push_back(std::shared_ptr<VolumeBase>(vol));
+ }
+ }
+ }
+
+ // Ugly last ditch effort, treat entire disk as partition
+ if (table == Table::kUnknown) {
+ ALOGD("%s: unknown partition table; trying entire device", mId.c_str());
+ VolumeBase* vol = new PublicVolume(mDevice);
+ mParts.push_back(std::shared_ptr<VolumeBase>(vol));
+ }
+
+ pclose(fp);
+ return OK;
+}
+
+status_t Disk::partitionPublic() {
+ // TODO: improve this code
+
+ struct disk_info dinfo;
+ memset(&dinfo, 0, sizeof(dinfo));
+
+ if (!(dinfo.part_lst = (struct part_info *) malloc(
+ MAX_NUM_PARTS * sizeof(struct part_info)))) {
+ SLOGE("Failed to malloc prt_lst");
+ return -1;
+ }
+
+ memset(dinfo.part_lst, 0, MAX_NUM_PARTS * sizeof(struct part_info));
+ dinfo.device = strdup(mDevPath.c_str());
+ dinfo.scheme = PART_SCHEME_MBR;
+ dinfo.sect_size = 512;
+ dinfo.skip_lba = 2048;
+ dinfo.num_lba = 0;
+ dinfo.num_parts = 1;
+
+ struct part_info *pinfo = &dinfo.part_lst[0];
+
+ pinfo->name = strdup("android_sdcard");
+ pinfo->flags |= PART_ACTIVE_FLAG;
+ pinfo->type = PC_PART_TYPE_FAT32;
+ pinfo->len_kb = -1;
+
+ int rc = apply_disk_config(&dinfo, 0);
+ if (rc) {
+ SLOGE("Failed to apply disk configuration (%d)", rc);
+ goto out;
+ }
+
+out:
+ free(pinfo->name);
+ free(dinfo.device);
+ free(dinfo.part_lst);
+
+ return rc;
+}
+
+status_t Disk::partitionPrivate() {
+ return -ENOTSUP;
+}
+
+status_t Disk::partitionMixed(int8_t ratio) {
+ return -ENOTSUP;
+}
+
+int Disk::getMaxMinors() {
+ // Figure out maximum partition devices supported
+ switch (major(mDevice)) {
+ case kMajorBlockScsi: {
+ // Per Documentation/devices.txt this is static
+ return 15;
+ }
+ case kMajorBlockMmc: {
+ // Per Documentation/devices.txt this is dynamic
+ std::string tmp;
+ if (!ReadFileToString(kSysfsMmcMaxMinors, &tmp)) {
+ ALOGW("Failed to read max minors");
+ return -errno;
+ }
+ return atoi(tmp.c_str());
+ }
+ }
+
+ ALOGW("Unsupported block major type %d", major(mDevice));
+ return -ENOTSUP;
+}
+
+} // namespace vold
+} // namespace android