commit 49784236b79e0362b6039c039bc7663c9f29bc63
author Yifan Hong <elsk@google.com> Tue Jan 08 13:33:52 2019 -0800
committer Yifan Hong <elsk@google.com> Thu Jan 10 10:49:05 2019 -0800
tree b4c2088cf91bdf1950a5bcf7eea671736474258f
parent 63d539405ff61624409ff288422b74d1bd233959

fs_mgr: overlayfs clears readonly on scratch devices

Fixes adb-remount-test and flashstation because the scratch device
was set to readonly before.

Test: adb-remount-test

Change-Id: I12551d1ed99fb7cfd04f84fcc2b77d3cb94275b2
Fixes: 122454600
Fixes: 122602260

fs_mgr/fs_mgr.cpp

diff --git a/fs_mgr/fs_mgr.cpp b/fs_mgr/fs_mgr.cpp
index 943fe10..9f6c550 100644
--- a/fs_mgr/fs_mgr.cpp
+++ b/fs_mgr/fs_mgr.cpp
@@ -523,13 +523,13 @@
 }
 
 // Mark the given block device as read-only, using the BLKROSET ioctl.
-bool fs_mgr_set_blk_ro(const std::string& blockdev) {
+bool fs_mgr_set_blk_ro(const std::string& blockdev, bool readonly) {
     unique_fd fd(TEMP_FAILURE_RETRY(open(blockdev.c_str(), O_RDONLY | O_CLOEXEC)));
     if (fd < 0) {
         return false;
     }
 
-    int ON = 1;
+    int ON = readonly;
     return ioctl(fd, BLKROSET, &ON) == 0;
 }
 

fs_mgr/fs_mgr_overlayfs.cpp

diff --git a/fs_mgr/fs_mgr_overlayfs.cpp b/fs_mgr/fs_mgr_overlayfs.cpp
index 0d1d5e7..6364ca9 100644
--- a/fs_mgr/fs_mgr_overlayfs.cpp
+++ b/fs_mgr/fs_mgr_overlayfs.cpp
@@ -598,7 +598,11 @@
     entry.mount_point = kScratchMountPoint;
     entry.fs_type = mnt_type;
     entry.flags = MS_RELATIME;
-    if (readonly) entry.flags |= MS_RDONLY;
+    if (readonly) {
+        entry.flags |= MS_RDONLY;
+    } else {
+        fs_mgr_set_blk_ro(device_path, false);
+    }
     auto save_errno = errno;
     auto mounted = fs_mgr_do_mount_one(entry) == 0;
     if (!mounted) {
@@ -656,6 +660,7 @@
         return false;
     }
     command += " " + scratch_device;
+    fs_mgr_set_blk_ro(scratch_device, false);
     auto ret = system(command.c_str());
     if (ret) {
         LERROR << "make " << mnt_type << " filesystem on " << scratch_device << " return=" << ret;

fs_mgr/fs_mgr_priv.h

diff --git a/fs_mgr/fs_mgr_priv.h b/fs_mgr/fs_mgr_priv.h
index 7d1159b..7842ca2 100644
--- a/fs_mgr/fs_mgr_priv.h
+++ b/fs_mgr/fs_mgr_priv.h
@@ -134,7 +134,7 @@
                           const std::chrono::milliseconds relative_timeout,
                           FileWaitMode wait_mode = FileWaitMode::Exists);
 
-bool fs_mgr_set_blk_ro(const std::string& blockdev);
+bool fs_mgr_set_blk_ro(const std::string& blockdev, bool readonly = true);
 bool fs_mgr_update_for_slotselect(Fstab* fstab);
 bool fs_mgr_is_device_unlocked();
 const std::string& get_android_dt_dir();