Re: [PATCH] lib/iov_iter.c: extract virt-contiguous pages in iov_iter_extract_bvec_pages

[David Howells]

Ming Lei <ming.lei@xxxxxxxxxx> wrote:

> All iov_iter_bvec() users only want to extract virt-contiguous pages from
> iov_iter_extract_pages() instead physical-contiguous pages.

What do you mean by "virt-contiguous"?  Virtual according to what mapping?

The reason for physical contiguity is that you can pass a set of physical
contiguous pages as a single DMA descriptor.  Therefore, at some point, you
might end up screwing up skb_splice_from_iter().  Currently, that's limited to
a PAGE_SIZE per fragment, but hopefully that will be fixed at some point.

David