Re: [2.1.98] - It compiled and I ran...

Stephen Williams (steve@icarus.icarus.com)
Sun, 26 Apr 1998 15:10:25 -0600


> 1. Find biggest free block within DMA availible range.
> 2. Move memory from either side out of the way, like up high in the
> memory space where ISA DMA can't happen.

kwr@kwr.hnv.com said:
> "Move" is the stumbling block here. You don't know what memory
> regions (forgot the structure names already *sigh*) use a given
> physical address unless you exhaustively check every PTE of every
> memory region in every process. Plus the buffer cache.

Plus device drivers. Some pci device may have a pointer to that memory
there. In other words, it might not be in any kernel tables at all.

-- 
Steve Williams                "The woods are lovely, dark and deep.
steve@icarus.com              But I have promises to keep,
steve@picturel.com            and lines to code before I sleep,
http://www.picturel.com       And lines to code before I sleep."

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