Re: [SeaBIOS] Question on block driver operation buffer

[Kevin O'Connor]

On Tue, Nov 01, 2011 at 08:21:11PM +0900, Daniel Castro wrote:
> Hello,
>
> When an int 13 operation is handles (suppose read), you are supposed
> to get sector X up until sector Y, where X is lba and count is Y. But
> I wonder, the buffer is the size of the operation? or is it a
> predefined size that never changes? I tend to incline for the later
> one, but how can I determine the size?

If the caller requests a read of 16 sectors that are 512 bytes each
then the caller must provide an 8K buffer to read into.  The SeaBIOS
code will pass this buffer to the low-level driver code (op->buf_fl) -
the driver should try to fully populate this buffer according to the
drive sector size and request size (op->count).

-Kevin