Re: [PATCH v2 1/3] mm: Introduce page_size()

[Andrew Morton <akpm@linux-foundation.org>]

On Tue, 23 Jul 2019 09:02:48 -0700 Matthew Wilcox <willy@infradead.org> wrote:

> On Mon, Jul 22, 2019 at 05:43:07PM -0700, Ira Weiny wrote:
> > > diff --git a/drivers/crypto/chelsio/chtls/chtls_io.c b/drivers/crypto/chelsio/chtls/chtls_io.c
> > > index 551bca6fef24..925be5942895 100644
> > > --- a/drivers/crypto/chelsio/chtls/chtls_io.c
> > > +++ b/drivers/crypto/chelsio/chtls/chtls_io.c
> > > @@ -1078,7 +1078,7 @@ int chtls_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
> > >  			bool merge;
> > >  
> > >  			if (page)
> > > -				pg_size <<= compound_order(page);
> > > +				pg_size = page_size(page);
> > >  			if (off < pg_size &&
> > >  			    skb_can_coalesce(skb, i, page, off)) {
> > >  				merge = 1;
> > > @@ -1105,8 +1105,7 @@ int chtls_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
> > >  							   __GFP_NORETRY,
> > >  							   order);
> > >  					if (page)
> > > -						pg_size <<=
> > > -							compound_order(page);
> > > +						pg_size <<= order;
> > 
> > Looking at the code I see pg_size should be PAGE_SIZE right before this so why
> > not just use the new call and remove the initial assignment?
> 
> This driver is really convoluted.  I wasn't certain I wouldn't break it
> in some horrid way.  I made larger changes to it originally, then they
> touched this part of the driver and I had to rework the patch to apply
> on top of their changes.  So I did something more minimal.
> 
> This, on top of what's in Andrew's tree, would be my guess, but I don't
> have the hardware.
> 
> diff --git a/drivers/crypto/chelsio/chtls/chtls_io.c b/drivers/crypto/chelsio/chtls/chtls_io.c
> index 925be5942895..d4eb0fcd04c7 100644
> --- a/drivers/crypto/chelsio/chtls/chtls_io.c
> +++ b/drivers/crypto/chelsio/chtls/chtls_io.c
> @@ -1073,7 +1073,7 @@ int chtls_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
>  		} else {
>  			int i = skb_shinfo(skb)->nr_frags;
>  			struct page *page = TCP_PAGE(sk);
> -			int pg_size = PAGE_SIZE;
> +			unsigned int pg_size = 0;
>  			int off = TCP_OFF(sk);
>  			bool merge;
>  
> @@ -1092,7 +1092,7 @@ int chtls_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
>  			if (page && off == pg_size) {
>  				put_page(page);
>  				TCP_PAGE(sk) = page = NULL;
> -				pg_size = PAGE_SIZE;
> +				pg_size = 0;
>  			}
>  
>  			if (!page) {
> @@ -1104,15 +1104,13 @@ int chtls_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
>  							   __GFP_NOWARN |
>  							   __GFP_NORETRY,
>  							   order);
> -					if (page)
> -						pg_size <<= order;
>  				}
>  				if (!page) {
>  					page = alloc_page(gfp);
> -					pg_size = PAGE_SIZE;
>  				}
>  				if (!page)
>  					goto wait_for_memory;
> +				pg_size = page_size(page);
>  				off = 0;
>  			}

I didn't do anything with this.  I assume the original patch (which has
been in -next since July 22) is good and the above is merely a cleanup?