Subject: Re: UVM aobj: Large VM objects.
To: None <cherry@mahiti.org>
From: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
List: tech-kern
Date: 03/06/2006 17:32:48
> Hi,
>
> The Kernel aobject (kernel_object_store) spans (VM_MAX_ADDRESS -
> VM_MIN_ADDRESS) on all ports. On ia64, the kernel VM range is
> determined by the size of an IA64 "region". This was inherited from
> FreeBSD MD code.
>
> The maximum number of pages required to map this size overflows type
> int, even with 16KB page sizes. Would the following ( and possibly
> more like this to come ) affect other areas of UVM ?
(although i doubt kernel_object really need to cover the entire region,)
making aobj 64-bit offset clean is a good idea.
however, i don't think long is appropriate here.
please introduce a 64-bit "page offset" type.
"typedef voff_t pgoff_t" should be fine.
YAMAMOTO Takashi