commit 3623a212e305f022a2fe279a4c13ec2a6513d6e7
author Zim <zezeozue@google.com> Fri Jul 19 16:46:53 2019 +0100
committer Nandana Dutt <nandana@google.com> Wed Aug 28 10:49:27 2019 +0100
tree 11e3cd1b0ff67be927160ec2b390f1f3c419257a
parent 7cd6ceb835d1116d97e01fe4757cfbe8531970d5

Mount /dev/fuse on /mnt/user/<userid>/<volumeid>

Since system_server cannot mount devices by itself,
add a binder interface to vold that system_server
can call to initiate this mount when required.

BUG: 135341433
Test: manual
Test: atest --test-mapping packages/providers/MediaProvider
Test: ExternalStorageHostTest DownloadProviderTests

Change-Id: If4fd02a1f1a8d921a3f96783d8c73e085c5b7ca1

VoldNativeService.cpp

diff --git a/VoldNativeService.cpp b/VoldNativeService.cpp
index 1762b70..9004b40 100644
--- a/VoldNativeService.cpp
+++ b/VoldNativeService.cpp
@@ -326,7 +326,8 @@
 }
 
 binder::Status VoldNativeService::mount(const std::string& volId, int32_t mountFlags,
-                                        int32_t mountUserId) {
+                                        int32_t mountUserId,
+                                        android::base::unique_fd* _aidl_return) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_ID(volId);
     ACQUIRE_LOCK;
@@ -343,6 +344,14 @@
     if (res != OK) {
         return translate(res);
     }
+
+    _aidl_return->reset(vol->getDeviceFd());
+    if (_aidl_return->get() == -1) {
+        // Let's not return invalid fd since binder will not allow null fds. Instead give it a
+        // default value.
+        _aidl_return->reset(open("/dev/null", O_RDONLY | O_CLOEXEC));
+    }
+
     if ((mountFlags & MOUNT_FLAG_PRIMARY) != 0) {
         res = VolumeManager::Instance()->setPrimary(vol);
         if (res != OK) {