Sudershan,it is 6.5 km from BIAL as per the Devanhalli Town Website,which I guess is official.click here
Also DHL is 5 km from BIAL as per IRI
I have considered this as the correct distance. Hence it is closest to Airport compared to DJL which is 8 km from BIAL as per IRI.
Thanks
PS:...
more... Even Wikipedia mentions it to be 5 km from DHL town south