[djcapelis]

Interestingly with SSD storage devices, control of the hardware can help a lot more as it can become possible to categorize, fully explore and if needed, ensure a particular behavior of commands like TRIM. Other filesystems have the unenviable task of running on any random piece of storage you throw at it, including things where the firmware straight up lies, or the hardware delays non-volatility past the point the filesystem assumes (potentially producing data loss in a crash) or similar types of problems.

Anyway. Overall, I think it's safe to say hardware control doesn't make most of filesystem development much simpler or easier. But there's a few interesting places it arguably does!

[zrm]

That doesn't really change anything about the filesystem design. A storage device can fail to write data it claims to have because of damage as well as design defects. When that happens, a reliable filesystem will detect it and a less reliable filesystem will catch on fire.

It also doesn't help to control 100% of the built-in storage if anybody can still plug in $GENERIC_USB_MASS_STORAGE_DEVICE and expect to use the same filesystem.