HLE: sceKernelAllocPartitionMemory volatile memory support (partition 5)

[Crow-bar]

The real psp, when requesting memory from the 5th partition, allocates it in the range 0x08400000 - 0x08800000.
This should fix some homebrew issue.

[unknownbrackets]

This needs to think about save states, at least. I think there were other restrictions though - might only be kernel mode or when volatile memory is locked?

-[Unknown]

[Crow-bar]

This needs to think about save states, at least. I think there were other restrictions though - might only be kernel mode or when volatile memory is locked?

-[Unknown]

Yes
This works in user mode, requires a prior call to sceKernelVolatileMemLock.
When saving or hibernating, psp waits for volatile memory to be unlocked (sceKernelVolatileMemUnlock).

Maybe something is missing in my code.

[hrydgard]

Yeah, this looks like something we should support. Unknown is right that it'll need versioning checks in the state save code.

For testing purposes and so forth, could you link to or name some homebrew that uses this?

[unknownbrackets]

I added the save state handling in #16058 (merging that will merge this as well.)

-[Unknown]

[Crow-bar]

Yeah, this looks like something we should support. Unknown is right that it'll need versioning checks in the state save code.

For testing purposes and so forth, > Yeah, this looks like something we should support. Unknown is right that it'll need versioning checks in the state save code.

For testing purposes and so forth, could you link to or name some homebrew that uses this?

DaedalusX64 (maybe a bad example)
https://github.com/DaedalusX64/daedalus/blob/master/Source/SysPSP/Utility/VolatileMemPSP.cpp

AGS
https://github.com/adventuregamestudio/ags/blob/master/PSP/malloc/malloc.c

Xash3d will use this):
https://github.com/Crow-bar/xash3d-fwgs

I wrote a small test:
https://github.com/Crow-bar/p5test

[unknownbrackets]

It seems like it allows allocating even if you don't lock volatile memory first (of course you'll get a fault if you access it.) I haven't thoroughly tested, but it also seems like locking/unlocking volatile won't reset allocations.

-[Unknown]