Remove exportid from cache inode key

Exportid is not needed in the cache inode key, and cache inodes are
going to be associated with multiple exports.

Signed-off-by: Frank S. Filz <ffilzlnx@mindspring.com>
Add req_op_context to cache_inode_new_entry

Signed-off-by: Frank S. Filz <ffilzlnx@mindspring.com>
MORE Protect export root and junction fields with gsh_export lock

Signed-off-by: Frank S. Filz <ffilzlnx@mindspring.com>
Add TODO notes in places with attribute races

Here are some places attributes are accessed without attr_lock.

Signed-off-by: Frank S. Filz <ffilzlnx@mindspring.com>
Don't call cache_inode_lock_trust_attrs in cache_inode_get

Anyone who uses attributes calls cache_inode_lock_trust_attrs before
using them in any case.

Signed-off-by: Frank S. Filz <ffilzlnx@mindspring.com>
Call cache_inode_kill_entry on unlink failure

Signed-off-by: Frank S. Filz <ffilzlnx@mindspring.com>