Fix multi-user and multi-storage with FUSE
Up until now, the FUSE mount logic has made two assumptions:
1. The primary external volume is an emulated volume on /data/media
2. Only the primary user is running, as user zero
These assumptions are fixed by the following changes
creating an EmulatedVolume per Android user and changing the
VolumeBase id format to append the user to the id, so
s/emulated/emulated-0/. This allows us mount separate volumes per user
Some additional refactorings to re-use/clean up code.
Test: adb shell sm set-virtual-disk and partition disk operations work
even after setting up a work profile
Bug: 135341433
Change-Id: Ifabaa12368e5a591fbcdce4ee71c83ff35fdac6b
diff --git a/model/EmulatedVolume.cpp b/model/EmulatedVolume.cpp
index c84fbb7..e6702c9 100644
--- a/model/EmulatedVolume.cpp
+++ b/model/EmulatedVolume.cpp
@@ -42,16 +42,17 @@
static const char* kFusePath = "/system/bin/sdcard";
-EmulatedVolume::EmulatedVolume(const std::string& rawPath)
+EmulatedVolume::EmulatedVolume(const std::string& rawPath, int userId)
: VolumeBase(Type::kEmulated), mFusePid(0) {
- setId("emulated");
+ setId(StringPrintf("emulated;%u", userId));
mRawPath = rawPath;
mLabel = "emulated";
}
-EmulatedVolume::EmulatedVolume(const std::string& rawPath, dev_t device, const std::string& fsUuid)
+EmulatedVolume::EmulatedVolume(const std::string& rawPath, dev_t device, const std::string& fsUuid,
+ int userId)
: VolumeBase(Type::kEmulated), mFusePid(0) {
- setId(StringPrintf("emulated:%u,%u", major(device), minor(device)));
+ setId(StringPrintf("emulated:%u,%u;%u", major(device), minor(device), userId));
mRawPath = rawPath;
mLabel = fsUuid;
}
@@ -90,17 +91,14 @@
LOG(INFO) << "Mounting emulated fuse volume";
android::base::unique_fd fd;
int user_id = getMountUserId();
- int result = MountUserFuse(user_id, label, &fd);
+ int result = MountUserFuse(user_id, getInternalPath(), label, &fd);
if (result != 0) {
PLOG(ERROR) << "Failed to mount emulated fuse volume";
return -result;
}
setFuseFd(std::move(fd));
-
- std::string pass_through_path(StringPrintf("/mnt/pass_through/%d/%s",
- user_id, label.c_str()));
- return BindMount(getInternalPath(), pass_through_path);
+ return 0;
}
if (!(mFusePid = fork())) {
@@ -163,18 +161,17 @@
if (getMountFlags() & MountFlags::kPrimary) {
label = "emulated";
}
- std::string path(StringPrintf("/mnt/user/%d/%s", getMountUserId(), label.c_str()));
- status_t result = ForceUnmount(path);
- if (result != OK) {
- // TODO(135341433): MNT_DETACH is needed for fuse because umount2 can fail with EBUSY.
- // Figure out why we get EBUSY and remove this special casing if possible.
- if (!umount2(path.c_str(), UMOUNT_NOFOLLOW | MNT_DETACH) || errno == EINVAL ||
- errno == ENOENT) {
- PLOG(INFO) << "ForceUnmount failed on emulated fuse volume";
- }
+
+ std::string fuse_path(StringPrintf("/mnt/user/%d/%s", getMountUserId(), label.c_str()));
+ std::string pass_through_path(
+ StringPrintf("/mnt/pass_through/%d/%s", getMountUserId(), label.c_str()));
+ if (UnmountUserFuse(pass_through_path, fuse_path) != OK) {
+ PLOG(INFO) << "UnmountUserFuse failed on emulated fuse volume";
+ return -errno;
}
- rmdir(path.c_str());
+ rmdir(fuse_path.c_str());
+ rmdir(pass_through_path.c_str());
setFuseFd(android::base::unique_fd());
return OK;
}