From: Nicolin Chen <nicolinc@nvidia.com> To: Christoph Hellwig <hch@infradead.org> Cc: <kwankhede@nvidia.com>, <corbet@lwn.net>, <hca@linux.ibm.com>, <gor@linux.ibm.com>, <agordeev@linux.ibm.com>, <borntraeger@linux.ibm.com>, <svens@linux.ibm.com>, <zhenyuw@linux.intel.com>, <zhi.a.wang@intel.com>, <jani.nikula@linux.intel.com>, <joonas.lahtinen@linux.intel.com>, <rodrigo.vivi@intel.com>, <tvrtko.ursulin@linux.intel.com>, <airlied@linux.ie>, <daniel@ffwll.ch>, <farman@linux.ibm.com>, <mjrosato@linux.ibm.com>, <pasic@linux.ibm.com>, <vneethv@linux.ibm.com>, <oberpar@linux.ibm.com>, <freude@linux.ibm.com>, <akrowiak@linux.ibm.com>, <jjherne@linux.ibm.com>, <alex.williamson@redhat.com>, <cohuck@redhat.com>, <jgg@nvidia.com>, <kevin.tian@intel.com>, <jchrist@linux.ibm.com>, <kvm@vger.kernel.org>, <linux-doc@vger.kernel.org>, <linux-kernel@vger.kernel.org>, <linux-s390@vger.kernel.org>, <intel-gvt-dev@lists.freedesktop.org>, <intel-gfx@lists.freedesktop.org>, <dri-devel@lists.freedesktop.org> Subject: Re: [RFT][PATCH v1 6/6] vfio: Replace phys_pfn with phys_page for vfio_pin_pages() Date: Fri, 17 Jun 2022 15:06:25 -0700 [thread overview] Message-ID: <Yqz64VK1IQ0QzXEe@Asurada-Nvidia> (raw) In-Reply-To: <YqxBLbu8yPJiwK6Z@infradead.org> On Fri, Jun 17, 2022 at 01:54:05AM -0700, Christoph Hellwig wrote: > There is a bunch of code an comments in the iommu type1 code that > suggest we can pin memory that is not page backed. Would you mind explaining the use case for pinning memory that isn't page backed? And do we have such use case so far? > > int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova, > > + int npage, int prot, struct page **phys_page) > > I don't think phys_page makes much sense as an argument name. > I'd just call this pages. OK. > > + phys_page[i] = pfn_to_page(vpfn->pfn); > > Please store the actual page pointer in the vfio_pfn structure. OK. > > remote_vaddr = dma->vaddr + (iova - dma->iova); > > - ret = vfio_pin_page_external(dma, remote_vaddr, &phys_pfn[i], > > + ret = vfio_pin_page_external(dma, remote_vaddr, &phys_pfn, > > do_accounting); > > Please just return the actual page from vaddr_get_pfns through > vfio_pin_pages_remote and vfio_pin_page_external, maybe even as a prep > patch as that is a fair amount of churn. I can do that. I tried once, but there were just too much changes inside type1 code that felt like a chain reaction. If we plan to eventually replace with IOMMUFD implementations, these changes in type1 might not be necessary, I thought.
WARNING: multiple messages have this Message-ID (diff)
From: Nicolin Chen <nicolinc@nvidia.com> To: Christoph Hellwig <hch@infradead.org> Cc: mjrosato@linux.ibm.com, linux-doc@vger.kernel.org, airlied@linux.ie, kevin.tian@intel.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kwankhede@nvidia.com, vneethv@linux.ibm.com, agordeev@linux.ibm.com, linux-s390@vger.kernel.org, kvm@vger.kernel.org, corbet@lwn.net, pasic@linux.ibm.com, jgg@nvidia.com, borntraeger@linux.ibm.com, intel-gfx@lists.freedesktop.org, zhi.a.wang@intel.com, jjherne@linux.ibm.com, farman@linux.ibm.com, jchrist@linux.ibm.com, gor@linux.ibm.com, hca@linux.ibm.com, alex.williamson@redhat.com, freude@linux.ibm.com, rodrigo.vivi@intel.com, intel-gvt-dev@lists.freedesktop.org, akrowiak@linux.ibm.com, tvrtko.ursulin@linux.intel.com, cohuck@redhat.com, oberpar@linux.ibm.com, svens@linux.ibm.com Subject: Re: [RFT][PATCH v1 6/6] vfio: Replace phys_pfn with phys_page for vfio_pin_pages() Date: Fri, 17 Jun 2022 15:06:25 -0700 [thread overview] Message-ID: <Yqz64VK1IQ0QzXEe@Asurada-Nvidia> (raw) In-Reply-To: <YqxBLbu8yPJiwK6Z@infradead.org> On Fri, Jun 17, 2022 at 01:54:05AM -0700, Christoph Hellwig wrote: > There is a bunch of code an comments in the iommu type1 code that > suggest we can pin memory that is not page backed. Would you mind explaining the use case for pinning memory that isn't page backed? And do we have such use case so far? > > int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova, > > + int npage, int prot, struct page **phys_page) > > I don't think phys_page makes much sense as an argument name. > I'd just call this pages. OK. > > + phys_page[i] = pfn_to_page(vpfn->pfn); > > Please store the actual page pointer in the vfio_pfn structure. OK. > > remote_vaddr = dma->vaddr + (iova - dma->iova); > > - ret = vfio_pin_page_external(dma, remote_vaddr, &phys_pfn[i], > > + ret = vfio_pin_page_external(dma, remote_vaddr, &phys_pfn, > > do_accounting); > > Please just return the actual page from vaddr_get_pfns through > vfio_pin_pages_remote and vfio_pin_page_external, maybe even as a prep > patch as that is a fair amount of churn. I can do that. I tried once, but there were just too much changes inside type1 code that felt like a chain reaction. If we plan to eventually replace with IOMMUFD implementations, these changes in type1 might not be necessary, I thought.
next prev parent reply other threads:[~2022-06-17 22:06 UTC|newest] Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-06-16 23:52 [RFT][PATCH v1 0/6] Update vfio_pin/unpin_pages API Nicolin Chen 2022-06-16 23:52 ` Nicolin Chen 2022-06-16 23:52 ` [RFT][PATCH v1 1/6] vfio/ap: Pass in physical address of ind to ap_aqic() Nicolin Chen 2022-06-16 23:52 ` Nicolin Chen 2022-06-20 10:00 ` Harald Freudenberger 2022-06-20 10:00 ` Harald Freudenberger 2022-06-21 21:01 ` Nicolin Chen 2022-06-21 21:01 ` [Intel-gfx] " Nicolin Chen 2022-06-21 21:01 ` Nicolin Chen 2022-06-16 23:52 ` [RFT][PATCH v1 2/6] vfio/ccw: Only pass in contiguous pages Nicolin Chen 2022-06-16 23:52 ` Nicolin Chen 2022-06-16 23:52 ` [RFT][PATCH v1 3/6] vfio: Pass in starting IOVA to vfio_pin/unpin_pages API Nicolin Chen 2022-06-16 23:52 ` Nicolin Chen 2022-06-17 8:42 ` Christoph Hellwig 2022-06-17 8:42 ` [Intel-gfx] " Christoph Hellwig 2022-06-17 21:57 ` Nicolin Chen 2022-06-17 21:57 ` Nicolin Chen 2022-06-22 1:18 ` Nicolin Chen 2022-06-22 1:18 ` [Intel-gfx] " Nicolin Chen 2022-06-22 1:18 ` Nicolin Chen 2022-06-16 23:52 ` [RFT][PATCH v1 4/6] vfio: Rename user_iova of vfio_dma_rw() Nicolin Chen 2022-06-16 23:52 ` Nicolin Chen 2022-06-16 23:52 ` [RFT][PATCH v1 5/6] vfio/ccw: Add kmap_local_page() for memcpy Nicolin Chen 2022-06-16 23:52 ` Nicolin Chen 2022-06-17 8:44 ` Christoph Hellwig 2022-06-17 8:44 ` [Intel-gfx] " Christoph Hellwig 2022-06-17 21:58 ` Nicolin Chen 2022-06-17 21:58 ` Nicolin Chen 2022-06-20 2:57 ` Jason Gunthorpe 2022-06-20 2:57 ` [Intel-gfx] " Jason Gunthorpe 2022-06-20 2:57 ` Jason Gunthorpe 2022-06-20 6:32 ` Christoph Hellwig 2022-06-20 6:32 ` [Intel-gfx] " Christoph Hellwig 2022-06-20 15:39 ` Jason Gunthorpe 2022-06-20 15:39 ` [Intel-gfx] " Jason Gunthorpe 2022-06-20 15:39 ` Jason Gunthorpe 2022-06-21 21:21 ` Nicolin Chen 2022-06-21 21:21 ` [Intel-gfx] " Nicolin Chen 2022-06-21 21:21 ` Nicolin Chen 2022-06-24 13:56 ` Jason Gunthorpe 2022-06-24 13:56 ` [Intel-gfx] " Jason Gunthorpe 2022-06-24 13:56 ` Jason Gunthorpe 2022-06-24 19:22 ` Nicolin Chen 2022-06-24 19:22 ` Nicolin Chen 2022-06-24 19:30 ` Jason Gunthorpe 2022-06-24 19:30 ` [Intel-gfx] " Jason Gunthorpe 2022-06-24 19:30 ` Jason Gunthorpe 2022-06-24 20:12 ` Nicolin Chen 2022-06-24 20:12 ` Nicolin Chen 2022-06-24 22:42 ` Jason Gunthorpe 2022-06-24 22:42 ` [Intel-gfx] " Jason Gunthorpe 2022-06-24 22:42 ` Jason Gunthorpe 2022-06-16 23:52 ` [RFT][PATCH v1 6/6] vfio: Replace phys_pfn with phys_page for vfio_pin_pages() Nicolin Chen 2022-06-16 23:52 ` Nicolin Chen 2022-06-17 8:54 ` Christoph Hellwig 2022-06-17 8:54 ` [Intel-gfx] " Christoph Hellwig 2022-06-17 22:06 ` Nicolin Chen [this message] 2022-06-17 22:06 ` Nicolin Chen 2022-06-19 6:18 ` Christoph Hellwig 2022-06-19 6:18 ` [Intel-gfx] " Christoph Hellwig 2022-06-19 6:41 ` Nicolin Chen 2022-06-19 6:41 ` Nicolin Chen 2022-06-20 3:00 ` Jason Gunthorpe 2022-06-20 3:00 ` [Intel-gfx] " Jason Gunthorpe 2022-06-20 3:00 ` Jason Gunthorpe 2022-06-20 5:51 ` Christoph Hellwig 2022-06-20 5:51 ` [Intel-gfx] " Christoph Hellwig 2022-06-20 6:37 ` Christoph Hellwig 2022-06-20 6:37 ` [Intel-gfx] " Christoph Hellwig 2022-06-20 15:36 ` Jason Gunthorpe 2022-06-20 15:36 ` [Intel-gfx] " Jason Gunthorpe 2022-06-20 15:36 ` Jason Gunthorpe 2022-06-21 21:47 ` Nicolin Chen 2022-06-21 21:47 ` [Intel-gfx] " Nicolin Chen 2022-06-21 21:47 ` Nicolin Chen
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=Yqz64VK1IQ0QzXEe@Asurada-Nvidia \ --to=nicolinc@nvidia.com \ --cc=agordeev@linux.ibm.com \ --cc=airlied@linux.ie \ --cc=akrowiak@linux.ibm.com \ --cc=alex.williamson@redhat.com \ --cc=borntraeger@linux.ibm.com \ --cc=cohuck@redhat.com \ --cc=corbet@lwn.net \ --cc=daniel@ffwll.ch \ --cc=dri-devel@lists.freedesktop.org \ --cc=farman@linux.ibm.com \ --cc=freude@linux.ibm.com \ --cc=gor@linux.ibm.com \ --cc=hca@linux.ibm.com \ --cc=hch@infradead.org \ --cc=intel-gfx@lists.freedesktop.org \ --cc=intel-gvt-dev@lists.freedesktop.org \ --cc=jani.nikula@linux.intel.com \ --cc=jchrist@linux.ibm.com \ --cc=jgg@nvidia.com \ --cc=jjherne@linux.ibm.com \ --cc=joonas.lahtinen@linux.intel.com \ --cc=kevin.tian@intel.com \ --cc=kvm@vger.kernel.org \ --cc=kwankhede@nvidia.com \ --cc=linux-doc@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-s390@vger.kernel.org \ --cc=mjrosato@linux.ibm.com \ --cc=oberpar@linux.ibm.com \ --cc=pasic@linux.ibm.com \ --cc=rodrigo.vivi@intel.com \ --cc=svens@linux.ibm.com \ --cc=tvrtko.ursulin@linux.intel.com \ --cc=vneethv@linux.ibm.com \ --cc=zhenyuw@linux.intel.com \ --cc=zhi.a.wang@intel.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.