Re: ramfs problem... (unlink of sparse file in "D" state)

[Alan Cox]

> Umm... Details, please? Are you talking about 2^32 or about fs layout limits?
> The former may very well belong to VFS - no arguments here. The latter...
> And yes, fs layout limits are visible - for ext2 they can be as low as 2^24
> blocks.

The SuS rules require write checks

resource limit
	if that stops all of the write
			SIGXFZ
			EFBIG
	else short write

!O_LARGEFILE and > off_t limit
	if that stops all of the write
			SIGXFZ
			EFBIG
	else short write

over fs limit
	if that stops all the write
			SIGXFZ
			EFBIG
	else short write

truncate has to honour the resource and fs limit. ftruncate also checks
the O_LARGEFILE limit.

Finally some OS's actually let you F_SETFL O_LARGEFILE.

I can put all that in the VFS so I did (right now the ext2 size calculator is
wrong but thats proof of concept detail). Just need to shift if over from
ext2/file.c

Alan