From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: Re: [PATCH v5 7/7] iommu/dma: Move PCI window region reservation back into dma specific path. Date: Thu, 22 Mar 2018 10:21:48 -0600 Message-ID: <20180322102148.29afce09@w520.home> References: <20180315163509.17740-1-shameerali.kolothum.thodi@huawei.com> <20180315163509.17740-8-shameerali.kolothum.thodi@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180315163509.17740-8-shameerali.kolothum.thodi-hv44wF8Li93QT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Shameer Kolothum Cc: kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, pmorel-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, xuwei5-C8/M+/jPZTeaMJb+Lgu22Q@public.gmane.org, linuxarm-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: iommu@lists.linux-foundation.org On Thu, 15 Mar 2018 16:35:09 +0000 Shameer Kolothum wrote: > This pretty much reverts commit 273df9635385 ("iommu/dma: Make PCI > window reservation generic") by moving the PCI window region > reservation back into the dma specific path so that these regions > doesn't get exposed via the IOMMU API interface. With this change, > the vfio interface will report only iommu specific reserved regions > to the user space. > > Cc: Robin Murphy > Cc: Joerg Roedel > Signed-off-by: Shameer Kolothum > --- As currently ordered, we expose the iova list to the user in 5/7 with the PCI window reservations still intact. Isn't that a bisection problem? This patch should come before the iova list is expose to the user. This is otherwise independent, so I can pop it up in the stack on commit, but I'd need an ack from Joerg and Robin to take it via my tree. Thanks, Alex > drivers/iommu/dma-iommu.c | 54 ++++++++++++++++++++++------------------------- > 1 file changed, 25 insertions(+), 29 deletions(-) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index f05f3cf..ddcbbdb 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -167,40 +167,16 @@ EXPORT_SYMBOL(iommu_put_dma_cookie); > * @list: Reserved region list from iommu_get_resv_regions() > * > * IOMMU drivers can use this to implement their .get_resv_regions callback > - * for general non-IOMMU-specific reservations. Currently, this covers host > - * bridge windows for PCI devices and GICv3 ITS region reservation on ACPI > - * based ARM platforms that may require HW MSI reservation. > + * for general non-IOMMU-specific reservations. Currently, this covers GICv3 > + * ITS region reservation on ACPI based ARM platforms that may require HW MSI > + * reservation. > */ > void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list) > { > - struct pci_host_bridge *bridge; > - struct resource_entry *window; > - > - if (!is_of_node(dev->iommu_fwspec->iommu_fwnode) && > - iort_iommu_msi_get_resv_regions(dev, list) < 0) > - return; > - > - if (!dev_is_pci(dev)) > - return; > - > - bridge = pci_find_host_bridge(to_pci_dev(dev)->bus); > - resource_list_for_each_entry(window, &bridge->windows) { > - struct iommu_resv_region *region; > - phys_addr_t start; > - size_t length; > - > - if (resource_type(window->res) != IORESOURCE_MEM) > - continue; > > - start = window->res->start - window->offset; > - length = window->res->end - window->res->start + 1; > - region = iommu_alloc_resv_region(start, length, 0, > - IOMMU_RESV_RESERVED); > - if (!region) > - return; > + if (!is_of_node(dev->iommu_fwspec->iommu_fwnode)) > + iort_iommu_msi_get_resv_regions(dev, list); > > - list_add_tail(®ion->list, list); > - } > } > EXPORT_SYMBOL(iommu_dma_get_resv_regions); > > @@ -229,6 +205,23 @@ static int cookie_init_hw_msi_region(struct iommu_dma_cookie *cookie, > return 0; > } > > +static void iova_reserve_pci_windows(struct pci_dev *dev, > + struct iova_domain *iovad) > +{ > + struct pci_host_bridge *bridge = pci_find_host_bridge(dev->bus); > + struct resource_entry *window; > + unsigned long lo, hi; > + > + resource_list_for_each_entry(window, &bridge->windows) { > + if (resource_type(window->res) != IORESOURCE_MEM) > + continue; > + > + lo = iova_pfn(iovad, window->res->start - window->offset); > + hi = iova_pfn(iovad, window->res->end - window->offset); > + reserve_iova(iovad, lo, hi); > + } > +} > + > static int iova_reserve_iommu_regions(struct device *dev, > struct iommu_domain *domain) > { > @@ -238,6 +231,9 @@ static int iova_reserve_iommu_regions(struct device *dev, > LIST_HEAD(resv_regions); > int ret = 0; > > + if (dev_is_pci(dev)) > + iova_reserve_pci_windows(to_pci_dev(dev), iovad); > + > iommu_get_resv_regions(dev, &resv_regions); > list_for_each_entry(region, &resv_regions, list) { > unsigned long lo, hi;