init: fstab: add support to read fstab entries from device tree
for early mount, we need a way to tell init where to find vendor,
odm partitions (also system in case of non-A/B devices). Also, that
needs to be independent of kernel cmdline since the cmdline will likely
exceed its limit.
The change adds support for parse and create fstab entries that can be
directly sent to the fs_mgr for mounting partitions early in init first
stage.
Sample DT entry to mount vendor partition early on angler-
firmware {
android {
compatible = "android,firmware";
fstab {
compatible = "android,fstab";
vendor {
compatible = "android,vendor";
dev = "/dev/block/platform/soc.0/f9824900.sdhci/by-name/vendor";
type = "ext4";
mnt_flags = "ro,barrier=1,inode_readahead_blks=8";
fsmgr_flags = "wait";
};
};
};
};
b/27805372
Test: Boot angler and sailfish with early "vendor" partition mount by
adding aforementioned DT node and enable CONFIG_PROC_DEVICETREE in kernel
Change-Id: I669013e3fdb157e88719436534f63989dec95d60
Signed-off-by: Sandeep Patil <sspatil@google.com>
diff --git a/init/init.cpp b/init/init.cpp
index 973573f..eb7431c 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -477,28 +477,48 @@
}
}
-static void process_kernel_dt() {
- static const char android_dir[] = "/proc/device-tree/firmware/android";
+static constexpr char android_dt_dir[] = "/proc/device-tree/firmware/android";
- std::string file_name = StringPrintf("%s/compatible", android_dir);
+static bool is_dt_compatible() {
+ std::string dt_value;
+ std::string file_name = StringPrintf("%s/compatible", android_dt_dir);
- std::string dt_file;
- android::base::ReadFileToString(file_name, &dt_file);
- if (!dt_file.compare("android,firmware")) {
+ android::base::ReadFileToString(file_name, &dt_value);
+ if (!dt_value.compare("android,firmware")) {
LOG(ERROR) << "firmware/android is not compatible with 'android,firmware'";
- return;
+ return false;
}
- std::unique_ptr<DIR, int(*)(DIR*)>dir(opendir(android_dir), closedir);
+ return true;
+}
+
+static bool is_dt_fstab_compatible() {
+ std::string dt_value;
+ std::string file_name = StringPrintf("%s/%s/compatible", android_dt_dir, "fstab");
+
+ android::base::ReadFileToString(file_name, &dt_value);
+ if (!dt_value.compare("android,fstab")) {
+ LOG(ERROR) << "firmware/android/fstab is not compatible with 'android,fstab'";
+ return false;
+ }
+
+ return true;
+}
+
+static void process_kernel_dt() {
+ if (!is_dt_compatible()) return;
+
+ std::unique_ptr<DIR, int(*)(DIR*)>dir(opendir(android_dt_dir), closedir);
if (!dir) return;
+ std::string dt_file;
struct dirent *dp;
while ((dp = readdir(dir.get())) != NULL) {
if (dp->d_type != DT_REG || !strcmp(dp->d_name, "compatible") || !strcmp(dp->d_name, "name")) {
continue;
}
- file_name = StringPrintf("%s/%s", android_dir, dp->d_name);
+ std::string file_name = StringPrintf("%s/%s", android_dt_dir, dp->d_name);
android::base::ReadFileToString(file_name, &dt_file);
std::replace(dt_file.begin(), dt_file.end(), ',', '.');
@@ -625,34 +645,98 @@
}
}
-/* Imports the fstab info from cmdline. */
-static std::string import_cmdline_fstab() {
- std::string fstabfile;
- import_kernel_cmdline(false,
- [&](const std::string& key, const std::string& value, bool in_qemu __attribute__((__unused__))) {
- if (key == "androidboot.fstab") {
- fstabfile = value;
- }
- });
- return fstabfile;
+static std::string import_dt_fstab() {
+ std::string fstab;
+ if (!is_dt_compatible() || !is_dt_fstab_compatible()) {
+ return fstab;
+ }
+
+ std::string fstabdir_name = StringPrintf("%s/fstab", android_dt_dir);
+ std::unique_ptr<DIR, int (*)(DIR*)> fstabdir(opendir(fstabdir_name.c_str()), closedir);
+ if (!fstabdir) return fstab;
+
+ dirent* dp;
+ while ((dp = readdir(fstabdir.get())) != NULL) {
+ // skip over name and compatible
+ if (dp->d_type != DT_DIR) {
+ continue;
+ }
+
+ // skip if its not 'vendor', 'odm' or 'system'
+ if (strcmp(dp->d_name, "odm") && strcmp(dp->d_name, "system") &&
+ strcmp(dp->d_name, "vendor")) {
+ continue;
+ }
+
+ // create <dev> <mnt_point> <type> <mnt_flags> <fsmgr_flags>\n
+ std::vector<std::string> fstab_entry;
+ std::string file_name;
+ std::string value;
+ file_name = StringPrintf("%s/%s/dev", fstabdir_name.c_str(), dp->d_name);
+ if (!android::base::ReadFileToString(file_name, &value)) {
+ LOG(ERROR) << "dt_fstab: Failed to find device for partition " << dp->d_name;
+ fstab.clear();
+ break;
+ }
+ // trim the terminating '\0' out
+ value.resize(value.size() - 1);
+ fstab_entry.push_back(value);
+ fstab_entry.push_back(StringPrintf("/%s", dp->d_name));
+
+ file_name = StringPrintf("%s/%s/type", fstabdir_name.c_str(), dp->d_name);
+ if (!android::base::ReadFileToString(file_name, &value)) {
+ LOG(ERROR) << "dt_fstab: Failed to find type for partition " << dp->d_name;
+ fstab.clear();
+ break;
+ }
+ value.resize(value.size() - 1);
+ fstab_entry.push_back(value);
+
+ file_name = StringPrintf("%s/%s/mnt_flags", fstabdir_name.c_str(), dp->d_name);
+ if (!android::base::ReadFileToString(file_name, &value)) {
+ LOG(ERROR) << "dt_fstab: Failed to find type for partition " << dp->d_name;
+ fstab.clear();
+ break;
+ }
+ value.resize(value.size() - 1);
+ fstab_entry.push_back(value);
+
+ file_name = StringPrintf("%s/%s/fsmgr_flags", fstabdir_name.c_str(), dp->d_name);
+ if (!android::base::ReadFileToString(file_name, &value)) {
+ LOG(ERROR) << "dt_fstab: Failed to find type for partition " << dp->d_name;
+ fstab.clear();
+ break;
+ }
+ value.resize(value.size() - 1);
+ fstab_entry.push_back(value);
+
+ fstab += android::base::Join(fstab_entry, " ");
+ fstab += '\n';
+ }
+
+ return fstab;
}
-/* Early mount vendor and ODM partitions. The fstab info is read from kernel cmdline. */
+/* Early mount vendor and ODM partitions. The fstab is read from device-tree. */
static bool early_mount() {
- // TODO: read fstab entries from device tree instead of
- // kernel cmdline
- std::string fstab_file = import_cmdline_fstab();
- if (fstab_file.empty()) {
- LOG(INFO) << "Early mount skipped (missing fstab argument)";
+ std::string fstab = import_dt_fstab();
+ if (fstab.empty()) {
+ LOG(INFO) << "Early mount skipped (missing fstab in device tree)";
return true;
}
- std::unique_ptr<struct fstab, void(*)(fstab*)> tab(fs_mgr_read_fstab(fstab_file.c_str()),
- fs_mgr_free_fstab);
+ std::unique_ptr<FILE, decltype(&fclose)> fstab_file(
+ fmemopen(static_cast<void*>(const_cast<char*>(fstab.c_str())), fstab.length(), "r"), fclose);
+ if (!fstab_file) {
+ PLOG(ERROR) << "Early mount failed to open fstab file in memory";
+ return false;
+ }
+
+ std::unique_ptr<struct fstab, decltype(&fs_mgr_free_fstab)> tab(
+ fs_mgr_read_fstab_file(fstab_file.get()), fs_mgr_free_fstab);
if (!tab) {
- LOG(ERROR) << "Early mount failed to read fstab: " << fstab_file;
- // continue to allow booting normally if this happened.
- return true;
+ LOG(ERROR) << "Early mount fsmgr failed to load fstab from kernel:" << std::endl << fstab;
+ return false;
}
// find out fstab records for odm, system and vendor
@@ -674,92 +758,88 @@
int count_odm = 0, count_vendor = 0, count_system = 0;
// create the devices we need..
- device_init(nullptr,
- [&](uevent* uevent) -> coldboot_action_t {
- if (!strncmp(uevent->subsystem, "firmware", 8)) {
- return COLDBOOT_CONTINUE;
- }
+ device_init(nullptr, [&](uevent* uevent) -> coldboot_action_t {
+ if (!strncmp(uevent->subsystem, "firmware", 8)) {
+ return COLDBOOT_CONTINUE;
+ }
- // we need platform devices to create symlinks
- if (!strncmp(uevent->subsystem, "platform", 8)) {
- return COLDBOOT_CREATE;
- }
+ // we need platform devices to create symlinks
+ if (!strncmp(uevent->subsystem, "platform", 8)) {
+ return COLDBOOT_CREATE;
+ }
- // Ignore everything that is not a block device
- if (strncmp(uevent->subsystem, "block", 5)) {
- return COLDBOOT_CONTINUE;
- }
+ // Ignore everything that is not a block device
+ if (strncmp(uevent->subsystem, "block", 5)) {
+ return COLDBOOT_CONTINUE;
+ }
- coldboot_action_t ret;
- bool create_this_node = false;
- if (uevent->partition_name) {
- // prefix match partition names so we create device nodes for
- // A/B-ed partitions
- if (!found_odm && !strncmp(uevent->partition_name, "odm", 3)) {
- LOG(VERBOSE) << "early_mount: found (" << uevent->partition_name
- << ") partition";
+ coldboot_action_t ret;
+ bool create_this_node = false;
+ if (uevent->partition_name) {
+ // prefix match partition names so we create device nodes for
+ // A/B-ed partitions
+ if (!found_odm && !strncmp(uevent->partition_name, "odm", 3)) {
+ LOG(VERBOSE) << "early_mount: found (" << uevent->partition_name << ") partition";
- // wait twice for A/B-ed partitions
- count_odm++;
- if (!is_ab) {
- found_odm = true;
- } else if (count_odm == 2) {
- found_odm = true;
- }
-
- create_this_node = true;
- } else if (!found_system && !strncmp(uevent->partition_name, "system", 6)) {
- LOG(VERBOSE) << "early_mount: found (" << uevent->partition_name
- << ") partition";
-
- count_system++;
- if (!is_ab) {
- found_system = true;
- } else if (count_system == 2) {
- found_system = true;
- }
-
- create_this_node = true;
- } else if (!found_vendor && !strncmp(uevent->partition_name, "vendor", 6)) {
- LOG(VERBOSE) << "early_mount: found (" << uevent->partition_name
- << ") partition";
- count_vendor++;
- if (!is_ab) {
- found_vendor = true;
- } else if (count_vendor == 2) {
- found_vendor = true;
- }
-
- create_this_node = true;
+ // wait twice for A/B-ed partitions
+ count_odm++;
+ if (!is_ab) {
+ found_odm = true;
+ } else if (count_odm == 2) {
+ found_odm = true;
}
- }
- // if we found all other partitions already, create this
- // node and stop coldboot. If this is a prefix matched
- // partition, create device node and continue. For everything
- // else skip the device node
- if (found_odm && found_system && found_vendor) {
- ret = COLDBOOT_STOP;
- } else if (create_this_node) {
- ret = COLDBOOT_CREATE;
- } else {
- ret = COLDBOOT_CONTINUE;
- }
+ create_this_node = true;
+ } else if (!found_system && !strncmp(uevent->partition_name, "system", 6)) {
+ LOG(VERBOSE) << "early_mount: found (" << uevent->partition_name << ") partition";
- return ret;
- });
+ count_system++;
+ if (!is_ab) {
+ found_system = true;
+ } else if (count_system == 2) {
+ found_system = true;
+ }
+
+ create_this_node = true;
+ } else if (!found_vendor && !strncmp(uevent->partition_name, "vendor", 6)) {
+ LOG(VERBOSE) << "early_mount: found (" << uevent->partition_name << ") partition";
+ count_vendor++;
+ if (!is_ab) {
+ found_vendor = true;
+ } else if (count_vendor == 2) {
+ found_vendor = true;
+ }
+
+ create_this_node = true;
+ }
+ }
+
+ // if we found all other partitions already, create this
+ // node and stop coldboot. If this is a prefix matched
+ // partition, create device node and continue. For everything
+ // else skip the device node
+ if (found_odm && found_system && found_vendor) {
+ ret = COLDBOOT_STOP;
+ } else if (create_this_node) {
+ ret = COLDBOOT_CREATE;
+ } else {
+ ret = COLDBOOT_CONTINUE;
+ }
+
+ return ret;
+ });
// TODO: add support to mount partitions w/ verity
int ret = 0;
if (odm_rec &&
- (ret = fs_mgr_do_mount(tab.get(), odm_rec->mount_point, odm_rec->blk_device, NULL))) {
+ (ret = fs_mgr_do_mount(tab.get(), odm_rec->mount_point, odm_rec->blk_device, NULL))) {
PLOG(ERROR) << "early_mount: fs_mgr_do_mount returned error for mounting odm";
return false;
}
if (vendor_rec &&
- (ret = fs_mgr_do_mount(tab.get(), vendor_rec->mount_point, vendor_rec->blk_device, NULL))) {
+ (ret = fs_mgr_do_mount(tab.get(), vendor_rec->mount_point, vendor_rec->blk_device, NULL))) {
PLOG(ERROR) << "early_mount: fs_mgr_do_mount returned error for mounting vendor";
return false;
}