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

["Weiny, Ira" <ira.weiny@intel.com>]

> On Fri, Sep 20, 2019 at 04:28:48PM -0700, Andrew Morton wrote:
> > 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?
> 
> Yes, just a cleanup.  Since Atul didn't offer an opinion, I assume he doesn't
> care.

Agreed I think what went in is fine.

Ira