Btrfs: implement inode_operations callback tmpfile
Btrfs: implement inode_operations callback tmpfile

This implements the tmpfile callback of struct inode_operations, introduced
in the linux kernel 3.11, and implemented already by some filesystems. This
callback is invoked by the VFS when the flag O_TMPFILE is passed to the open
system call.

Signed-off-by: Filipe David Borba Manana <e0fcd583df77ec6c08e6d1257619cc1216ddc994@gmail.com>
Signed-off-by: Chris Mason <e2e8c5702d8ed5f565988a1cf5bb35c9ce199e5e@fb.com>
Reviewed-by: David Sterba <a2ce9d316ca04d17b520237d2846a218b8284e52@suse.cz>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs