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SubjectRe: O_DIRECT
"A month of sundays ago wrote:"
> >
> > What functions does a block driver have to implement in order to
> > support read/write when it has been opened with O_DIRECT from user
> > space.

> Remeber that the memory you read/write from must be page aligned (ie
> mmap /dev/zero not malloc) and reads and writes must be multiples of the
> page size. I think block devices work on 2.4 too, but I forget (otherwise
> you can use raw devices).

I do believe you are right. Multiples of 4096 seem to work fine. No
support needed in the block device driver.

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