[Buildroot] How to allocate 100% of memory to /tmp?

[Nimai Mahajan]

We are working on a recovery system using Buildroot that operates
solely in memory. Some data we send over is 1-2GB in size so we'd like
to allocate all of the memory to /tmp. I'm not sure where the setting
is to change this but on a system with 2 GB of memory for example,
/tmp is given 1 GB and /dev/shm the other 1 GB. How do I map this
differently in a safe manner? Or is this normal behavior? Thanks!