ramfs: kernel heap (slab) memory leak when creating and deleting mmap'ed files

[X512]

This is hrev56567.

"slab area" memory constantly increase when repeating this cycle

1. create file and set size
2. mmap
3. memset(ptr, 0xcc, size)
4. munmap
5. delete file and close fd

Leaked memory is not freed after unmount.

It can be also some VFS or VM memory leak.

[X512]

No leak if mmap is not used (use write instead for example). Problem is also reproduced in my ​shmfs. It always use VMAnonumousCache for storage, so leak seems to be in VM kernel code, not in ramfs/shmfs.

[X512]

It seems that VMCache objects are leaking (including physical pages) if mmap is called at least once.

[waddlesplash]

Merged in hrev56581

[bipolar]

For anyone wondering... I assume waddlesplash meant: hrev56582.

[waddlesplash]

Yeah, copy/paste error.