commit d4c7f3b28ce3811b9d84ea8fa8f5595a8b23aa5e
author David Anderson <dvander@google.com> Thu Oct 07 16:23:47 2021 +0000
committer Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com> Thu Oct 07 16:23:47 2021 +0000
tree 74838eceaeec322ef8d25e07dbe7803b813aa141
parent 9bf6083f63365fa6a8efb1a8a16622044952f90a
parent d23803f00a8124041b4a224b550a2312bc935bd6

Merge "adds LO_FLAGS_AUTOCLEAR for loop device of zram backing device" am: af09c15049 am: d50f25bed6 am: d23803f00a

Original change: https://android-review.googlesource.com/c/platform/system/core/+/1834393

Change-Id: Icbf141a0e5a6ba4ca78da0639a779ad9a86c707a

fs_mgr/fs_mgr.cpp

diff --git a/fs_mgr/fs_mgr.cpp b/fs_mgr/fs_mgr.cpp
index 002b302..07e1e6b 100644
--- a/fs_mgr/fs_mgr.cpp
+++ b/fs_mgr/fs_mgr.cpp
@@ -2119,6 +2119,9 @@
         PERROR << "Cannot open " << loop_device;
         return false;
     }
+    if (!LoopControl::SetAutoClearStatus(loop_fd.get())) {
+        PERROR << "Failed set LO_FLAGS_AUTOCLEAR for " << loop_device;
+    }
     if (!LoopControl::EnableDirectIo(loop_fd.get())) {
         return false;
     }

fs_mgr/libdm/include/libdm/loop_control.h

diff --git a/fs_mgr/libdm/include/libdm/loop_control.h b/fs_mgr/libdm/include/libdm/loop_control.h
index ad53c11..f519054 100644
--- a/fs_mgr/libdm/include/libdm/loop_control.h
+++ b/fs_mgr/libdm/include/libdm/loop_control.h
@@ -46,6 +46,9 @@
     // Enable Direct I/O on a loop device. This requires kernel 4.9+.
     static bool EnableDirectIo(int fd);
 
+    // Set LO_FLAGS_AUTOCLEAR on a loop device.
+    static bool SetAutoClearStatus(int fd);
+
     LoopControl(const LoopControl&) = delete;
     LoopControl& operator=(const LoopControl&) = delete;
     LoopControl& operator=(LoopControl&&) = default;

fs_mgr/libdm/loop_control.cpp

diff --git a/fs_mgr/libdm/loop_control.cpp b/fs_mgr/libdm/loop_control.cpp
index 2e40a18..32d5f38 100644
--- a/fs_mgr/libdm/loop_control.cpp
+++ b/fs_mgr/libdm/loop_control.cpp
@@ -133,6 +133,16 @@
     return true;
 }
 
+bool LoopControl::SetAutoClearStatus(int fd) {
+    struct loop_info64 info = {};
+
+    info.lo_flags |= LO_FLAGS_AUTOCLEAR;
+    if (ioctl(fd, LOOP_SET_STATUS64, &info)) {
+        return false;
+    }
+    return true;
+}
+
 LoopDevice::LoopDevice(android::base::borrowed_fd fd, const std::chrono::milliseconds& timeout_ms,
                        bool auto_close)
     : fd_(fd), owned_fd_(-1) {