Hello.
Hugh Dickins wrote:
(though much more verbose: please simplify if you see a better way).
How about the following?
unsigned char *tail = buf + buflen - slop;
unsigned char pad[4];
if (rw == READ) {
if (slop <= 2)
ioread16_rep(data_addr, pad, 1);
else
ioread32_rep(data_addr, pad, 1);
memcpy(tail, pad, slop);
Too many tabs on the memcpy.
Hey, this is not a patch, and I was using Thunderbird's msg editor --
which isn;t really good to tabs. :-)
} else {
memcpy(pad, tail, slop);
memset(pad + slop, 0, 4 - slop);
And we could make that line even more complicated!
We could use memzero() but memset() should boil down to it anyway.
But I think unsigned char pad[4] = {0, 0, 0, 0} would be better.
Not really, we don't need to waste time initiazlizing it on reads --
I hope you understand that it will require real code to write all those
zeros?). Besides, only {0} should be enough as other entries should be
implitly zeroed).
Though Alan didn't have it initialized at all: I don't know if
that was oversight or superior knowledge. In Alan's case, one
should usually assume the latter.
These bytes can be anything actually as a device should just ignore them.
if (slop <= 2)
iowrite16_rep(data_addr, pad, 1);
else
iowrite32_rep(data_addr, pad, 1);
}
Well, I don't know.
I do. :-)
I felt really pleased with using ioread16_rep
and the char array in my original patch, where slop might be 1 or 2
or 3; but once it comes down to always one single PIO op, I felt
it too lazy to be using the _rep form.
It should do the Right Thing WRT the byte reordering (which is a lack
thereof ;-) while your code had to muck with it explicitly. And of
course it's shorter -- because of that.
I really don't care, whatever works and best satisfies Alan.
I thought we should care about general user satisfaction, not just
Alan's... :-)
- return words << 2;
+
+ return buflen + (buflen & 1);
return (buflen + 1) & ~1;
Well, I guess I could just have posted my own patch... :-)
Yes, do go ahead, I'm not desperate to get my name in there!
I'm not actually very enthusiastic in getting blamed for the
breakage, given the Alan's example. ;-)
Hugh
MBR, Sergei
--
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
