Re: [PATCH v14 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing

From: Claire Chang <tientzu@chromium.org>
To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: heikki.krogerus@linux.intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	peterz@infradead.org, benh@kernel.crashing.org,
	joonas.lahtinen@linux.intel.com, dri-devel@lists.freedesktop.org,
	chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org,
	Frank Rowand <frowand.list@gmail.com>,
	mingo@kernel.org, Jianxiong Gao <jxgao@google.com>,
	Stefano Stabellini <sstabellini@kernel.org>,
	Saravana Kannan <saravanak@google.com>,
	mpe@ellerman.id.au,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Christoph Hellwig <hch@lst.de>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Dan Williams <dan.j.williams@intel.com>,
	matthew.auld@intel.com, Nicolas Boichat <drinkcat@chromium.org>,
	thomas.hellstrom@linux.intel.com,
	Jim Quinlan <james.quinlan@broadcom.com>,
	Will Deacon <will@kernel.org>,
	intel-gfx@lists.freedesktop.org,
	maarten.lankhorst@linux.intel.com, jani.nikula@linux.intel.com,
	Rob Herring <robh+dt@kernel.org>,
	rodrigo.vivi@intel.com, Bjorn Helgaas <bhelgaas@google.com>,
	boris.ostrovsky@oracle.com,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	jgross@suse.com, airlied@linux.ie,
	Thierry Reding <treding@nvidia.com>,
	linuxppc-dev@lists.ozlabs.org,
	Randy Dunlap <rdunlap@infradead.org>,
	Qian Cai <quic_qiancai@quicinc.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	lkml <linux-kernel@vger.kernel.org>,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Daniel Vetter <daniel@ffwll.ch>,
	xypron.glpk@gmx.de, Tom Lendacky <thomas.lendacky@amd.com>,
	Robin Murphy <robin.murphy@arm.com>,
	bauerman@linux.ibm.com
Subject: Re: [PATCH v14 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
Date: Thu, 24 Jun 2021 23:58:57 +0800	[thread overview]
Message-ID: <CALiNf2_WCVodEZJz9PaCTgk_c8LpOAcD4=YZTLDMVyorJs3ESQ@mail.gmail.com> (raw)
In-Reply-To: <YNSq56zyJ7EYdTcI@char.us.oracle.com>

On Thu, Jun 24, 2021 at 11:56 PM Konrad Rzeszutek Wilk
<konrad.wilk@oracle.com> wrote:
>
> On Thu, Jun 24, 2021 at 10:10:51AM -0400, Qian Cai wrote:
> >
> >
> > On 6/24/2021 7:48 AM, Will Deacon wrote:
> > > Ok, diff below which attempts to tackle the offset issue I mentioned as
> > > well. Qian Cai -- please can you try with these changes?
> >
> > This works fine.
>
> Cool. Let me squash this patch in #6 and rebase the rest of them.
>
> Claire, could you check the devel/for-linus-5.14 say by end of today to
> double check that I didn't mess anything up please?

I just submitted v15 here
(https://lore.kernel.org/patchwork/cover/1451322/) in case it's
helpful.
I'll double check of course. Thanks for the efforts!

>
> Will,
>
> Thank you for generating the fix! I am going to run it on x86 and Xen
> to make sure all is good (granted last time I ran devel/for-linus-5.14
> on that setup I didn't see any errors so I need to double check
> I didn't do something silly like run a wrong kernel).
>
>
> >
> > >
> > > Will
> > >
> > > --->8
> > >
> > > diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
> > > index 175b6c113ed8..39284ff2a6cd 100644
> > > --- a/include/linux/swiotlb.h
> > > +++ b/include/linux/swiotlb.h
> > > @@ -116,7 +116,9 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
> > >
> > >  static inline bool is_swiotlb_force_bounce(struct device *dev)
> > >  {
> > > -       return dev->dma_io_tlb_mem->force_bounce;
> > > +       struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
> > > +
> > > +       return mem && mem->force_bounce;
> > >  }
> > >
> > >  void __init swiotlb_exit(void);
> > > diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
> > > index 44be8258e27b..0ffbaae9fba2 100644
> > > --- a/kernel/dma/swiotlb.c
> > > +++ b/kernel/dma/swiotlb.c
> > > @@ -449,6 +449,7 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
> > >                 dma_get_min_align_mask(dev) & ~(IO_TLB_SIZE - 1);
> > >         unsigned int nslots = nr_slots(alloc_size), stride;
> > >         unsigned int index, wrap, count = 0, i;
> > > +       unsigned int offset = swiotlb_align_offset(dev, orig_addr);
> > >         unsigned long flags;
> > >
> > >         BUG_ON(!nslots);
> > > @@ -497,7 +498,7 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
> > >         for (i = index; i < index + nslots; i++) {
> > >                 mem->slots[i].list = 0;
> > >                 mem->slots[i].alloc_size =
> > > -                       alloc_size - ((i - index) << IO_TLB_SHIFT);
> > > +                       alloc_size - (offset + ((i - index) << IO_TLB_SHIFT));
> > >         }
> > >         for (i = index - 1;
> > >              io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&
> > >
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu