| Message ID | 9-v2-8d1dc464eac9+10f-iommu_all_defdom_jgg@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iommu: Make default_domain's mandatory | expand |
On 2023-05-16 01:00, Jason Gunthorpe wrote: > Robin was able to check the documentation and what fsl_pamu has > historically called detach_dev() is really putting the IOMMU into an > IDENTITY mode. Unfortunately it was the other way around - it's the call to fsl_setup_liodns() from fsl_pamu_probe() which leaves everything in bypass by default (the PAACE_ATM_NO_XLATE part, IIRC), whereas the detach_device() call here ends up disabling the given device's LIODN altogether. There doesn't appear to have ever been any code anywhere for putting things *back* into bypass after using a VFIO domain, so as-is these default domains would probably break all DMA :( Thanks, Robin. > Move to the new core support for ARM_DMA_USE_IOMMU by defining > ops->identity_domain. This is a ppc driver without any dma_ops, so ensure > the identity translation is the default domain. > > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> > --- > drivers/iommu/fsl_pamu_domain.c | 32 +++++++++++++++++++++++++++++--- > 1 file changed, 29 insertions(+), 3 deletions(-) > > diff --git a/drivers/iommu/fsl_pamu_domain.c b/drivers/iommu/fsl_pamu_domain.c > index bce37229709965..ca4f5ebf028783 100644 > --- a/drivers/iommu/fsl_pamu_domain.c > +++ b/drivers/iommu/fsl_pamu_domain.c > @@ -283,15 +283,21 @@ static int fsl_pamu_attach_device(struct iommu_domain *domain, > return ret; > } > > -static void fsl_pamu_set_platform_dma(struct device *dev) > +static int fsl_pamu_identity_attach(struct iommu_domain *platform_domain, > + struct device *dev) > { > struct iommu_domain *domain = iommu_get_domain_for_dev(dev); > - struct fsl_dma_domain *dma_domain = to_fsl_dma_domain(domain); > + struct fsl_dma_domain *dma_domain; > const u32 *prop; > int len; > struct pci_dev *pdev = NULL; > struct pci_controller *pci_ctl; > > + if (domain == platform_domain || !domain) > + return 0; > + > + dma_domain = to_fsl_dma_domain(domain); > + > /* > * Use LIODN of the PCI controller while detaching a > * PCI device. > @@ -312,8 +318,18 @@ static void fsl_pamu_set_platform_dma(struct device *dev) > detach_device(dev, dma_domain); > else > pr_debug("missing fsl,liodn property at %pOF\n", dev->of_node); > + return 0; > } > > +static struct iommu_domain_ops fsl_pamu_identity_ops = { > + .attach_dev = fsl_pamu_identity_attach, > +}; > + > +static struct iommu_domain fsl_pamu_identity_domain = { > + .type = IOMMU_DOMAIN_IDENTITY, > + .ops = &fsl_pamu_identity_ops, > +}; > + > /* Set the domain stash attribute */ > int fsl_pamu_configure_l1_stash(struct iommu_domain *domain, u32 cpu) > { > @@ -447,12 +463,22 @@ static struct iommu_device *fsl_pamu_probe_device(struct device *dev) > return &pamu_iommu; > } > > +static int fsl_pamu_def_domain_type(struct device *dev) > +{ > + /* > + * This platform does not use dma_ops at all so the normally the iommu > + * must be in identity mode > + */ > + return IOMMU_DOMAIN_IDENTITY; > +} > + > static const struct iommu_ops fsl_pamu_ops = { > + .identity_domain = &fsl_pamu_identity_domain, > + .def_domain_type = &fsl_pamu_def_domain_type, > .capable = fsl_pamu_capable, > .domain_alloc = fsl_pamu_domain_alloc, > .probe_device = fsl_pamu_probe_device, > .device_group = fsl_pamu_device_group, > - .set_platform_dma_ops = fsl_pamu_set_platform_dma, > .default_domain_ops = &(const struct iommu_domain_ops) { > .attach_dev = fsl_pamu_attach_device, > .iova_to_phys = fsl_pamu_iova_to_phys,
diff --git a/drivers/iommu/fsl_pamu_domain.c b/drivers/iommu/fsl_pamu_domain.c index bce37229709965..ca4f5ebf028783 100644 --- a/drivers/iommu/fsl_pamu_domain.c +++ b/drivers/iommu/fsl_pamu_domain.c @@ -283,15 +283,21 @@ static int fsl_pamu_attach_device(struct iommu_domain *domain, return ret; } -static void fsl_pamu_set_platform_dma(struct device *dev) +static int fsl_pamu_identity_attach(struct iommu_domain *platform_domain, + struct device *dev) { struct iommu_domain *domain = iommu_get_domain_for_dev(dev); - struct fsl_dma_domain *dma_domain = to_fsl_dma_domain(domain); + struct fsl_dma_domain *dma_domain; const u32 *prop; int len; struct pci_dev *pdev = NULL; struct pci_controller *pci_ctl; + if (domain == platform_domain || !domain) + return 0; + + dma_domain = to_fsl_dma_domain(domain); + /* * Use LIODN of the PCI controller while detaching a * PCI device. @@ -312,8 +318,18 @@ static void fsl_pamu_set_platform_dma(struct device *dev) detach_device(dev, dma_domain); else pr_debug("missing fsl,liodn property at %pOF\n", dev->of_node); + return 0; } +static struct iommu_domain_ops fsl_pamu_identity_ops = { + .attach_dev = fsl_pamu_identity_attach, +}; + +static struct iommu_domain fsl_pamu_identity_domain = { + .type = IOMMU_DOMAIN_IDENTITY, + .ops = &fsl_pamu_identity_ops, +}; + /* Set the domain stash attribute */ int fsl_pamu_configure_l1_stash(struct iommu_domain *domain, u32 cpu) { @@ -447,12 +463,22 @@ static struct iommu_device *fsl_pamu_probe_device(struct device *dev) return &pamu_iommu; } +static int fsl_pamu_def_domain_type(struct device *dev) +{ + /* + * This platform does not use dma_ops at all so the normally the iommu + * must be in identity mode + */ + return IOMMU_DOMAIN_IDENTITY; +} + static const struct iommu_ops fsl_pamu_ops = { + .identity_domain = &fsl_pamu_identity_domain, + .def_domain_type = &fsl_pamu_def_domain_type, .capable = fsl_pamu_capable, .domain_alloc = fsl_pamu_domain_alloc, .probe_device = fsl_pamu_probe_device, .device_group = fsl_pamu_device_group, - .set_platform_dma_ops = fsl_pamu_set_platform_dma, .default_domain_ops = &(const struct iommu_domain_ops) { .attach_dev = fsl_pamu_attach_device, .iova_to_phys = fsl_pamu_iova_to_phys,
Robin was able to check the documentation and what fsl_pamu has historically called detach_dev() is really putting the IOMMU into an IDENTITY mode. Move to the new core support for ARM_DMA_USE_IOMMU by defining ops->identity_domain. This is a ppc driver without any dma_ops, so ensure the identity translation is the default domain. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> --- drivers/iommu/fsl_pamu_domain.c | 32 +++++++++++++++++++++++++++++--- 1 file changed, 29 insertions(+), 3 deletions(-)