Description of problem:

Calling `setfacl` on a volume whose bricks are on a tmpfs mount sets the ACLs on the brick dirs/files, but calling `getfacl` on the FUSE-mounted volume does not show the ACLs most of the time. However, if a file is `fallocate`d on that same tmpfs mount, and that file is mounted via loopback, that problem does not occur; `getfacl` always returns the ACLs on the FUSE-mounted volume. 


Version-Release number of selected component (if applicable):
Tested on gluster 5.3 and 4.1.


How reproducible: always


Steps to Reproduce:
1. Mount a ramdisk
mount -t tmpfs -o auto,nodev,nosuid,noexec,nodiratime,size=5G tmpfs /mnt/test

2. Make a test user
adduser testuser

3. Create volume
gluster volume create gv0 replica 3 server{1..3}:/mnt/test/brick

4. Start volume
gluster volume start gv0

5. FUSE-mount the volume
mkdir /mnt/gv0 && mount -t glusterfs -o acl server1,server2,server3:/gv0 /mnt/gv0

6. Create test file
echo "test" > /mnt/gv0/test

7. Set ACL
setfacl -m u:testuser:rwx /mnt/gv0/test

8. Check ACL
Run several times to see that it is usually missing the ACL
getfacl /mnt/gv0/test



Actual results:
ACLs are not there

Expected results:
ACLs should be there

Additional info:
When the ACLs aren't there, the gluster log has a trace that indicates `posix-acl-autoload` returns -1. When the ACLs are present, that message is not in the log.

This seems to be a problem with gluster reading the ACLs from a tmpfs partition.