LittleFS on Pico

I am using the earlephilhower build core for the Pico. I added code for a LittleFS on an original Pico. Everything compiles. However, the mount of the LittleFS fails at runtime. I believe it is because the compiler does not know about this filesystem and therefore assigns all the Flash to the sketch. I spent several hours searching for an example or some setting where I can tell the system how much of a file system I want. No Joy.
How do I specify the max sketch size and the amount for the file system?
Thanks.

Under Project Tasks, it I choose Build Filesystem Image, then it fails as below:

Building in release mode
Flash size: 2.00MB
Sketch size: 2.00MB
Filesystem size: 0.00MB
Maximium Sketch size: 2093056 EEPROM start: 0x101ff000 Filesystem start: 0x101ff000 Filesystem end: 0x101ff000
Building file system image from ‘data’ directory to .pio/build/pico/littlefs.bin
error: image size not specified, can’t create filesystem
*** [.pio/build/pico/littlefs.bin] Error 1

Well if you give no space to the filesystem then it can’t be created. Set the filesystem size per given example

https://arduino-pico.readthedocs.io/en/latest/platformio.html#examples

Thank you for pointing out an example of the ini setting for reserving filesystem space. That part of the project is working now.