Re: [SeaBIOS] Question on block driver operation buffer - SeaBIOS

1 Nov 2011


      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