How to find file and RPM relation in Linux?

At times, I need to find where a file comes from. i.e. what package/RPM owns that specific file. In following example, I found two methods to find file-RPM relationship.

[root@servername lib]# yum whatprovides libext4fs.so.2

Loaded plugins: aliases, changelog, downloadonly, fastestmirror, filter-data, keys, kmod, list-data, protect-packages, protectbase, rhnplugin, security, tmprepo, verify, versionlock

This system is not registered with RHN.

RHN support will be disabled.

Loading mirror speeds from cached hostfile

e4fsprogs-libs-1.41.9-3.el5.i386 : Ext4 filesystem-specific static libraries and headers

Repo        : installed

Matched from:

Other       : Provides-match: libext4fs.so.2





[root@servername lib]# rpm -qf libext4fs.so.2

e4fsprogs-libs-1.41.9-3.el5