Re: [PATCH v2 2/3] iov_iter: introduce iov_iter_pin_user_pages*() routines

[John Hubbard]

On 8/29/20 7:58 AM, Christoph Hellwig wrote:

On Sat, Aug 29, 2020 at 01:08:52AM -0700, John Hubbard wrote:

...

@@ -1280,7 +1281,11 @@ static inline ssize_t __pipe_get_pages(struct iov_iter 
*i,
        maxsize = n;
        n += *start;
        while (n > 0) {
-               get_page(*pages++ = pipe->bufs[iter_head & p_mask].page);
+               if (use_pup)
+                       pin_user_page(*pages++ = pipe->bufs[iter_head & 
p_mask].page);
+               else
+                       get_page(*pages++ = pipe->bufs[iter_head & 
p_mask].page);

Maybe this would become a little more readable with a local variable
and a little more verbosity:

                struct page *page = pipe->bufs[iter_head & p_mask].page;

                if (use_pup)
                        pin_user_page(page);
                else
                        get_page(page);

                *pages++ = page;

Yes, that is cleaner, I'll change to that, thanks.

thanks,
--
John Hubbard
NVIDIA