Michael S. Tsirkin
2023-Feb-15 11:48 UTC
[PATCH v2] vhost/vdpa: Add MSI translation tables to iommu for software-managed MSI
On Tue, Feb 07, 2023 at 08:08:43PM +0800, Nanyong Sun wrote:> From: Rong Wang <wangrong68 at huawei.com> > > Once enable iommu domain for one device, the MSI > translation tables have to be there for software-managed MSI. > Otherwise, platform with software-managed MSI without an > irq bypass function, can not get a correct memory write event > from pcie, will not get irqs. > The solution is to obtain the MSI phy base address from > iommu reserved region, and set it to iommu MSI cookie, > then translation tables will be created while request irq. > > Change log > ---------- > > v1->v2: > - add resv iotlb to avoid overlap mapping.put changelog after --- pls> Signed-off-by: Rong Wang <wangrong68 at huawei.com> > Signed-off-by: Nanyong Sun <sunnanyong at huawei.com> > --- > drivers/iommu/iommu.c | 1 + > drivers/vhost/vdpa.c | 59 ++++++++++++++++++++++++++++++++++++++++--- > 2 files changed, 57 insertions(+), 3 deletions(-) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index 5f6a85aea501..af9c064ad8b2 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -2623,6 +2623,7 @@ void iommu_get_resv_regions(struct device *dev, struct list_head *list) > if (ops->get_resv_regions) > ops->get_resv_regions(dev, list); > } > +EXPORT_SYMBOL(iommu_get_resv_regions); > > /** > * iommu_put_resv_regions - release resered regions > diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c > index ec32f785dfde..a58979da8acd 100644 > --- a/drivers/vhost/vdpa.c > +++ b/drivers/vhost/vdpa.c > @@ -49,6 +49,7 @@ struct vhost_vdpa { > struct completion completion; > struct vdpa_device *vdpa; > struct hlist_head as[VHOST_VDPA_IOTLB_BUCKETS]; > + struct vhost_iotlb resv_iotlb; > struct device dev; > struct cdev cdev; > atomic_t opened; > @@ -216,6 +217,8 @@ static int vhost_vdpa_reset(struct vhost_vdpa *v) > > v->in_batch = 0; > > + vhost_iotlb_reset(&v->resv_iotlb); > + > return vdpa_reset(vdpa); > } > > @@ -1013,6 +1016,10 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, > msg->iova + msg->size - 1 > v->range.last) > return -EINVAL; > > + if (vhost_iotlb_itree_first(&v->resv_iotlb, msg->iova, > + msg->iova + msg->size - 1)) > + return -EINVAL; > + > if (vhost_iotlb_itree_first(iotlb, msg->iova, > msg->iova + msg->size - 1)) > return -EEXIST; > @@ -1103,6 +1110,45 @@ static ssize_t vhost_vdpa_chr_write_iter(struct kiocb *iocb, > return vhost_chr_write_iter(dev, from); > } > > +static int vhost_vdpa_resv_iommu_region(struct iommu_domain *domain, struct device *dma_dev, > + struct vhost_iotlb *resv_iotlb) > +{ > + struct list_head dev_resv_regions; > + phys_addr_t resv_msi_base = 0; > + struct iommu_resv_region *region; > + int ret = 0; > + bool with_sw_msi = false; > + bool with_hw_msi = false; > + > + INIT_LIST_HEAD(&dev_resv_regions); > + iommu_get_resv_regions(dma_dev, &dev_resv_regions); > + > + list_for_each_entry(region, &dev_resv_regions, list) { > + ret = vhost_iotlb_add_range_ctx(resv_iotlb, region->start, > + region->start + region->length - 1, > + 0, 0, NULL); > + if (ret) { > + vhost_iotlb_reset(resv_iotlb); > + break; > + } > + > + if (region->type == IOMMU_RESV_MSI) > + with_hw_msi = true; > + > + if (region->type == IOMMU_RESV_SW_MSI) { > + resv_msi_base = region->start; > + with_sw_msi = true; > + } > + } > + > + if (!ret && !with_hw_msi && with_sw_msi) > + ret = iommu_get_msi_cookie(domain, resv_msi_base); > + > + iommu_put_resv_regions(dma_dev, &dev_resv_regions); > + > + return ret; > +} > + > static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v) > { > struct vdpa_device *vdpa = v->vdpa; > @@ -1128,11 +1174,16 @@ static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v) > > ret = iommu_attach_device(v->domain, dma_dev); > if (ret) > - goto err_attach; > + goto err_alloc_domain; > > - return 0; > + ret = vhost_vdpa_resv_iommu_region(v->domain, dma_dev, &v->resv_iotlb); > + if (ret) > + goto err_attach_device; > > -err_attach: > + return 0; > +err_attach_device: > + iommu_detach_device(v->domain, dma_dev); > +err_alloc_domain: > iommu_domain_free(v->domain); > return ret; > } > @@ -1385,6 +1436,8 @@ static int vhost_vdpa_probe(struct vdpa_device *vdpa) > goto err; > } > > + vhost_iotlb_init(&v->resv_iotlb, 0, 0); > + > r = dev_set_name(&v->dev, "vhost-vdpa-%u", minor); > if (r) > goto err; > -- > 2.25.1