Progress towards dynamic storage support.

To support external storage devices that are dynamically added and
removed at runtime, we're changing /mnt and /storage to be tmpfs that
are managed by vold.

To support primary storage being inserted/ejected at runtime in a
multi-user environment, we can no longer bind-mount each user into
place.  Instead, we have a new /storage/self/primary symlink which
is resolved through /mnt/user/n/primary, and which vold updates at
runtime.

Fix small mode bugs in FUSE daemon so it can be safely mounted
visible to all users on device.

Bug: 19993667
Change-Id: I0ebf4d10aba03d73d9a6fa37d4d43766be8a173b

3 files changed, 25 insertions, 23 deletions

diff --git a/rootdir/init.environ.rc.in b/rootdir/init.environ.rc.in
index 0064790..b34ea01 100644
--- a/rootdir/init.environ.rc.in
+++ b/rootdir/init.environ.rc.in
@@ -5,7 +5,7 @@ on init
     export ANDROID_ASSETS /system/app
     export ANDROID_DATA /data
     export ANDROID_STORAGE /storage
+    export EXTERNAL_STORAGE /sdcard
     export ASEC_MOUNTPOINT /mnt/asec
-    export LOOP_MOUNTPOINT /mnt/obb
     export BOOTCLASSPATH %BOOTCLASSPATH%
     export SYSTEMSERVERCLASSPATH %SYSTEMSERVERCLASSPATH%
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 70bb59b..9fad0ed 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -26,9 +26,6 @@ on early-init
 
     start ueventd
 
-    # create mountpoints
-    mkdir /mnt 0775 root system
-
 on init
     sysclktz 0
 
@@ -62,28 +59,29 @@ on init
     mkdir /cache 0770 system cache
     mkdir /config 0500 root root
 
+    # Mount staging areas for devices managed by vold
     # See storage config details at http://source.android.com/tech/storage/
-    mkdir /mnt/shell 0700 shell shell
-    mkdir /mnt/media_rw 0700 media_rw media_rw
-    mkdir /storage 0751 root sdcard_r
+    mkdir /mnt 0755 root system
+    mount tmpfs tmpfs /mnt mode=0755,uid=0,gid=1000
+    restorecon_recursive /mnt
 
-    # Directory for putting things only root should see.
     mkdir /mnt/secure 0700 root root
+    mkdir /mnt/secure/asec 0700 root root
+    mkdir /mnt/asec 0755 root system
+    mkdir /mnt/obb 0755 root system
+    mkdir /mnt/media_rw 0750 root media_rw
+    mkdir /mnt/user 0755 root root
+    mkdir /mnt/user/0 0755 root root
+
+    # sdcard_r is GID 1028
+    mkdir /storage 0751 root sdcard_r
+    mount tmpfs tmpfs /storage mode=0751,uid=0,gid=1028
+    restorecon_recursive /storage
 
-    # Directory for staging bindmounts
-    mkdir /mnt/secure/staging 0700 root root
-
-    # Directory-target for where the secure container
-    # imagefile directory will be bind-mounted
-    mkdir /mnt/secure/asec  0700 root root
-
-    # Secure container public mount points.
-    mkdir /mnt/asec  0700 root system
-    mount tmpfs tmpfs /mnt/asec mode=0755,gid=1000
-
-    # Filesystem image public mount points.
-    mkdir /mnt/obb 0700 root system
-    mount tmpfs tmpfs /mnt/obb mode=0755,gid=1000
+    # Symlink to keep legacy apps working in multi-user world
+    mkdir /storage/self 0751 root sdcard_r
+    symlink /storage/self/primary /sdcard
+    symlink /mnt/user/0/primary /storage/self/primary
 
     # memory control cgroup
     mkdir /dev/memcg 0700 root system
@@ -235,6 +233,9 @@ on post-fs-data
     # We restorecon /data in case the userdata partition has been reset.
     restorecon /data
 
+    # Emulated internal storage area
+    mkdir /data/media 0770 media_rw media_rw
+
     # Start bootcharting as soon as possible after the data partition is
     # mounted to collect more data.
     mkdir /data/bootchart 0755 shell shell
diff --git a/sdcard/sdcard.c b/sdcard/sdcard.c
index 599236f..2cb41e5 100644
--- a/sdcard/sdcard.c
+++ b/sdcard/sdcard.c
@@ -471,6 +471,7 @@ static void derive_permissions_locked(struct fuse* fuse, struct node *parent,
         node->perm = PERM_ROOT;
         node->userid = strtoul(node->name, NULL, 10);
         node->gid = multiuser_get_uid(node->userid, AID_SDCARD_R);
+        node->mode = 0771;
         break;
     case PERM_ROOT:
         /* Assume masked off by default. */
@@ -741,7 +742,7 @@ static void fuse_init(struct fuse *fuse, int fd, const char *source_path,
          * places user_id at the top directory level, with the actual roots
          * just below that. Shared OBB path is also at top level. */
         fuse->root.perm = PERM_LEGACY_PRE_ROOT;
-        fuse->root.mode = 0771;
+        fuse->root.mode = 0711;
         fuse->root.gid = AID_SDCARD_R;
         fuse->package_to_appid = hashmapCreate(256, str_hash, str_icase_equals);
         fuse->uid_with_rw = hashmapCreate(128, int_hash, int_equals);