update_engine: drop MTD logic
It has no users.
Note that I'm also dropping unit tests of the form:
EXPECT_TRUE(utils::SplitPartitionName("/dev/loop10_0", &disk, &part_num));
EXPECT_EQ("/dev/loop", disk);
EXPECT_EQ(10, part_num);
EXPECT_TRUE(utils::SplitPartitionName("/dev/loop28p11_0", &disk, &part_num));
EXPECT_EQ("/dev/loop28", disk);
EXPECT_EQ(11, part_num);
AFAICT, the part of the change that introduced these
(https://crrev.com/c/191785) was not based on any real issue; it was
(correctly) handling partition suffixes for loop devices (e.g., the 'p1'
in '/dev/loop0p1'), but the underscore syntax is specific to
ubi/ubiblock and should not apply to loop devices.
See the ubiblock naming code [1], analogous loop device naming code [2],
and the partition-name generation code [3].
[1] https://elixir.bootlin.com/linux/v5.1.15/source/drivers/mtd/ubi/block.c#L402
[2] https://elixir.bootlin.com/linux/v5.1.15/source/drivers/block/loop.c#L2012
[3] https://elixir.bootlin.com/linux/v5.1.15/source/block/partition-generic.c#L35
BUG=chromium:978563
TEST=unit tests
Change-Id: I38754a5060ed3c9e6b11fb53d82ff6fb79149c72
diff --git a/common/utils.cc b/common/utils.cc
index 34d97a2..3a234cb 100644
--- a/common/utils.cc
+++ b/common/utils.cc
@@ -83,49 +83,6 @@
// The path to the kernel's boot_id.
const char kBootIdPath[] = "/proc/sys/kernel/random/boot_id";
-// Return true if |disk_name| is an MTD or a UBI device. Note that this test is
-// simply based on the name of the device.
-bool IsMtdDeviceName(const string& disk_name) {
- return base::StartsWith(
- disk_name, "/dev/ubi", base::CompareCase::SENSITIVE) ||
- base::StartsWith(disk_name, "/dev/mtd", base::CompareCase::SENSITIVE);
-}
-
-// Return the device name for the corresponding partition on a NAND device.
-// WARNING: This function returns device names that are not mountable.
-string MakeNandPartitionName(int partition_num) {
- switch (partition_num) {
- case 2:
- case 4:
- case 6: {
- return base::StringPrintf("/dev/mtd%d", partition_num);
- }
- default: {
- return base::StringPrintf("/dev/ubi%d_0", partition_num);
- }
- }
-}
-
-// Return the device name for the corresponding partition on a NAND device that
-// may be mountable (but may not be writable).
-string MakeNandPartitionNameForMount(int partition_num) {
- switch (partition_num) {
- case 2:
- case 4:
- case 6: {
- return base::StringPrintf("/dev/mtd%d", partition_num);
- }
- case 3:
- case 5:
- case 7: {
- return base::StringPrintf("/dev/ubiblock%d_0", partition_num);
- }
- default: {
- return base::StringPrintf("/dev/ubi%d_0", partition_num);
- }
- }
-}
-
// If |path| is absolute, or explicit relative to the current working directory,
// leaves it as is. Otherwise, uses the system's temp directory, as defined by
// base::GetTempDir() and prepends it to |path|. On success stores the full
@@ -473,22 +430,6 @@
return false;
}
- size_t partition_name_len = string::npos;
- if (partition_name[last_nondigit_pos] == '_') {
- // NAND block devices have weird naming which could be something
- // like "/dev/ubiblock2_0". We discard "_0" in such a case.
- size_t prev_nondigit_pos =
- partition_name.find_last_not_of("0123456789", last_nondigit_pos - 1);
- if (prev_nondigit_pos == string::npos ||
- (prev_nondigit_pos + 1) == last_nondigit_pos) {
- LOG(ERROR) << "Unable to parse partition device name: " << partition_name;
- return false;
- }
-
- partition_name_len = last_nondigit_pos - prev_nondigit_pos;
- last_nondigit_pos = prev_nondigit_pos;
- }
-
if (out_disk_name) {
// Special case for MMC devices which have the following naming scheme:
// mmcblk0p2
@@ -501,8 +442,7 @@
}
if (out_partition_num) {
- string partition_str =
- partition_name.substr(last_nondigit_pos + 1, partition_name_len);
+ string partition_str = partition_name.substr(last_nondigit_pos + 1);
*out_partition_num = atoi(partition_str.c_str());
}
return true;
@@ -519,13 +459,6 @@
return string();
}
- if (IsMtdDeviceName(disk_name)) {
- // Special case for UBI block devices.
- // 1. ubiblock is not writable, we need to use plain "ubi".
- // 2. There is a "_0" suffix.
- return MakeNandPartitionName(partition_num);
- }
-
string partition_name = disk_name;
if (isdigit(partition_name.back())) {
// Special case for devices with names ending with a digit.
@@ -539,17 +472,6 @@
return partition_name;
}
-string MakePartitionNameForMount(const string& part_name) {
- if (IsMtdDeviceName(part_name)) {
- int partition_num;
- if (!SplitPartitionName(part_name, nullptr, &partition_num)) {
- return "";
- }
- return MakeNandPartitionNameForMount(partition_num);
- }
- return part_name;
-}
-
string ErrnoNumberAsString(int err) {
char buf[100];
buf[0] = '\0';
@@ -566,33 +488,6 @@
return lstat(path, &stbuf) == 0 && S_ISLNK(stbuf.st_mode) != 0;
}
-bool TryAttachingUbiVolume(int volume_num, int timeout) {
- const string volume_path = base::StringPrintf("/dev/ubi%d_0", volume_num);
- if (FileExists(volume_path.c_str())) {
- return true;
- }
-
- int exit_code;
- vector<string> cmd = {"ubiattach",
- "-m",
- base::StringPrintf("%d", volume_num),
- "-d",
- base::StringPrintf("%d", volume_num)};
- TEST_AND_RETURN_FALSE(Subprocess::SynchronousExec(cmd, &exit_code, nullptr));
- TEST_AND_RETURN_FALSE(exit_code == 0);
-
- cmd = {"ubiblock", "--create", volume_path};
- TEST_AND_RETURN_FALSE(Subprocess::SynchronousExec(cmd, &exit_code, nullptr));
- TEST_AND_RETURN_FALSE(exit_code == 0);
-
- while (timeout > 0 && !FileExists(volume_path.c_str())) {
- sleep(1);
- timeout--;
- }
-
- return FileExists(volume_path.c_str());
-}
-
bool MakeTempFile(const string& base_filename_template,
string* filename,
int* fd) {