On Thu, Jun 30, 2022 at 11:11:27PM +0100, Al Viro wrote:
> ... and the first half of that thing conflicts with "block: relax direct
> io memory alignment" in -next...
BTW, looking at that commit - are you sure that bio_put_pages() on failure
exit will do the right thing? We have grabbed a bunch of page references;
the amount if DIV_ROUND_UP(offset + size, PAGE_SIZE). And that's before
your
size = ALIGN_DOWN(size, bdev_logical_block_size(bio->bi_bdev));
in there. IMO the following would be more obviously correct:
size = iov_iter_get_pages(iter, pages, LONG_MAX, nr_pages, &offset);
if (unlikely(size <= 0))
return size ? size : -EFAULT;
nr_pages = DIV_ROUND_UP(size + offset, PAGE_SIZE);
size = ALIGN_DOWN(size, bdev_logical_block_size(bio->bi_bdev));
for (left = size, i = 0; left > 0; left -= len, i++) {
...
if (ret) {
while (i < nr_pages)
put_page(pages[i++]);
return ret;
}
...
and get rid of bio_put_pages() entirely. Objections?
