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[PATCH v4 4/7] iommu/riscv: Enable IOMMU registration and device probe.

Tomasz Jeznach posted 7 patches 1 year, 7 months ago
There is a newer version of this series
[PATCH v4 4/7] iommu/riscv: Enable IOMMU registration and device probe.
Posted by Tomasz Jeznach 1 year, 7 months ago 
Advertise IOMMU device and its core API.
Only minimal implementation for single identity domain type, without
per-group domain protection.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Tomasz Jeznach <tjeznach@rivosinc.com>
---
 drivers/iommu/riscv/iommu.c | 66 +++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)

diff --git a/drivers/iommu/riscv/iommu.c b/drivers/iommu/riscv/iommu.c
index 3c5a6b49669d..1f889daffb0e 100644
--- a/drivers/iommu/riscv/iommu.c
+++ b/drivers/iommu/riscv/iommu.c
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/iommu.h>
 #include <linux/kernel.h>
+#include <linux/pci.h>
 
 #include "iommu-bits.h"
 #include "iommu.h"
@@ -36,6 +37,60 @@ static void riscv_iommu_disable(struct riscv_iommu_device *iommu)
 	riscv_iommu_writel(iommu, RISCV_IOMMU_REG_PQCSR, 0);
 }
 
+static int riscv_iommu_attach_identity_domain(struct iommu_domain *iommu_domain,
+					      struct device *dev)
+{
+	/* Global pass-through already enabled, do nothing for now. */
+	return 0;
+}
+
+static struct iommu_domain riscv_iommu_identity_domain = {
+	.type = IOMMU_DOMAIN_IDENTITY,
+	.ops = &(const struct iommu_domain_ops) {
+		.attach_dev = riscv_iommu_attach_identity_domain,
+	}
+};
+
+static int riscv_iommu_device_domain_type(struct device *dev)
+{
+	return IOMMU_DOMAIN_IDENTITY;
+}
+
+static struct iommu_group *riscv_iommu_device_group(struct device *dev)
+{
+	if (dev_is_pci(dev))
+		return pci_device_group(dev);
+	return generic_device_group(dev);
+}
+
+static int riscv_iommu_of_xlate(struct device *dev, const struct of_phandle_args *args)
+{
+	return iommu_fwspec_add_ids(dev, args->args, 1);
+}
+
+static struct iommu_device *riscv_iommu_probe_device(struct device *dev)
+{
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+	struct riscv_iommu_device *iommu;
+
+	if (!fwspec->iommu_fwnode->dev || !fwspec->num_ids)
+		return ERR_PTR(-ENODEV);
+
+	iommu = dev_get_drvdata(fwspec->iommu_fwnode->dev);
+	if (!iommu)
+		return ERR_PTR(-ENODEV);
+
+	return &iommu->iommu;
+}
+
+static const struct iommu_ops riscv_iommu_ops = {
+	.of_xlate = riscv_iommu_of_xlate,
+	.identity_domain = &riscv_iommu_identity_domain,
+	.def_domain_type = riscv_iommu_device_domain_type,
+	.device_group = riscv_iommu_device_group,
+	.probe_device = riscv_iommu_probe_device,
+};
+
 static int riscv_iommu_init_check(struct riscv_iommu_device *iommu)
 {
 	u64 ddtp;
@@ -71,6 +126,7 @@ static int riscv_iommu_init_check(struct riscv_iommu_device *iommu)
 
 void riscv_iommu_remove(struct riscv_iommu_device *iommu)
 {
+	iommu_device_unregister(&iommu->iommu);
 	iommu_device_sysfs_remove(&iommu->iommu);
 }
 
@@ -95,5 +151,15 @@ int riscv_iommu_init(struct riscv_iommu_device *iommu)
 		return dev_err_probe(iommu->dev, rc,
 				     "cannot register sysfs interface\n");
 
+	rc = iommu_device_register(&iommu->iommu, &riscv_iommu_ops, iommu->dev);
+	if (rc) {
+		dev_err_probe(iommu->dev, rc, "cannot register iommu interface\n");
+		goto err_remove_sysfs;
+	}
+
 	return 0;
+
+err_remove_sysfs:
+	iommu_device_sysfs_remove(&iommu->iommu);
+	return rc;
 }
-- 
2.34.1
Re: [PATCH v4 4/7] iommu/riscv: Enable IOMMU registration and device probe.
Posted by Zong Li 1 year, 7 months ago 
On Sat, May 4, 2024 at 12:13 AM Tomasz Jeznach <tjeznach@rivosinc.com> wrote:
>
> Advertise IOMMU device and its core API.
> Only minimal implementation for single identity domain type, without
> per-group domain protection.
>
> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
> Signed-off-by: Tomasz Jeznach <tjeznach@rivosinc.com>
> ---
>  drivers/iommu/riscv/iommu.c | 66 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 66 insertions(+)
>
> diff --git a/drivers/iommu/riscv/iommu.c b/drivers/iommu/riscv/iommu.c
> index 3c5a6b49669d..1f889daffb0e 100644
> --- a/drivers/iommu/riscv/iommu.c
> +++ b/drivers/iommu/riscv/iommu.c
> @@ -17,6 +17,7 @@
>  #include <linux/init.h>
>  #include <linux/iommu.h>
>  #include <linux/kernel.h>
> +#include <linux/pci.h>
>
>  #include "iommu-bits.h"
>  #include "iommu.h"
> @@ -36,6 +37,60 @@ static void riscv_iommu_disable(struct riscv_iommu_device *iommu)
>         riscv_iommu_writel(iommu, RISCV_IOMMU_REG_PQCSR, 0);
>  }
>
> +static int riscv_iommu_attach_identity_domain(struct iommu_domain *iommu_domain,
> +                                             struct device *dev)
> +{
> +       /* Global pass-through already enabled, do nothing for now. */
> +       return 0;
> +}
> +
> +static struct iommu_domain riscv_iommu_identity_domain = {
> +       .type = IOMMU_DOMAIN_IDENTITY,
> +       .ops = &(const struct iommu_domain_ops) {
> +               .attach_dev = riscv_iommu_attach_identity_domain,
> +       }
> +};
> +
> +static int riscv_iommu_device_domain_type(struct device *dev)
> +{
> +       return IOMMU_DOMAIN_IDENTITY;
> +}
> +
> +static struct iommu_group *riscv_iommu_device_group(struct device *dev)
> +{
> +       if (dev_is_pci(dev))
> +               return pci_device_group(dev);
> +       return generic_device_group(dev);
> +}
> +
> +static int riscv_iommu_of_xlate(struct device *dev, const struct of_phandle_args *args)
> +{
> +       return iommu_fwspec_add_ids(dev, args->args, 1);
> +}
> +
> +static struct iommu_device *riscv_iommu_probe_device(struct device *dev)
> +{
> +       struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +       struct riscv_iommu_device *iommu;
> +
> +       if (!fwspec->iommu_fwnode->dev || !fwspec->num_ids)
> +               return ERR_PTR(-ENODEV);

It seems to me that we might need to ensure fwspec is not NULL before
accessing fwspec->iommu_fwnode, otherwise, it will cause NULL pointer
dereference.

> +
> +       iommu = dev_get_drvdata(fwspec->iommu_fwnode->dev);
> +       if (!iommu)
> +               return ERR_PTR(-ENODEV);
> +
> +       return &iommu->iommu;
> +}
> +
> +static const struct iommu_ops riscv_iommu_ops = {
> +       .of_xlate = riscv_iommu_of_xlate,
> +       .identity_domain = &riscv_iommu_identity_domain,
> +       .def_domain_type = riscv_iommu_device_domain_type,
> +       .device_group = riscv_iommu_device_group,
> +       .probe_device = riscv_iommu_probe_device,
> +};
> +
>  static int riscv_iommu_init_check(struct riscv_iommu_device *iommu)
>  {
>         u64 ddtp;
> @@ -71,6 +126,7 @@ static int riscv_iommu_init_check(struct riscv_iommu_device *iommu)
>
>  void riscv_iommu_remove(struct riscv_iommu_device *iommu)
>  {
> +       iommu_device_unregister(&iommu->iommu);
>         iommu_device_sysfs_remove(&iommu->iommu);
>  }
>
> @@ -95,5 +151,15 @@ int riscv_iommu_init(struct riscv_iommu_device *iommu)
>                 return dev_err_probe(iommu->dev, rc,
>                                      "cannot register sysfs interface\n");
>
> +       rc = iommu_device_register(&iommu->iommu, &riscv_iommu_ops, iommu->dev);
> +       if (rc) {
> +               dev_err_probe(iommu->dev, rc, "cannot register iommu interface\n");
> +               goto err_remove_sysfs;
> +       }
> +
>         return 0;
> +
> +err_remove_sysfs:
> +       iommu_device_sysfs_remove(&iommu->iommu);
> +       return rc;
>  }
> --
> 2.34.1
>
>
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv
Re: [PATCH v4 4/7] iommu/riscv: Enable IOMMU registration and device probe.
Posted by Tomasz Jeznach 1 year, 7 months ago 
On Mon, May 13, 2024 at 10:56 PM Zong Li <zong.li@sifive.com> wrote:
>
> On Sat, May 4, 2024 at 12:13 AM Tomasz Jeznach <tjeznach@rivosinc.com> wrote:
> >
> > Advertise IOMMU device and its core API.
> > Only minimal implementation for single identity domain type, without
> > per-group domain protection.
> >
> > Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
> > Signed-off-by: Tomasz Jeznach <tjeznach@rivosinc.com>
> > ---
> >  drivers/iommu/riscv/iommu.c | 66 +++++++++++++++++++++++++++++++++++++
> >  1 file changed, 66 insertions(+)
> >
> > diff --git a/drivers/iommu/riscv/iommu.c b/drivers/iommu/riscv/iommu.c
> > index 3c5a6b49669d..1f889daffb0e 100644
> > --- a/drivers/iommu/riscv/iommu.c
> > +++ b/drivers/iommu/riscv/iommu.c
> > @@ -17,6 +17,7 @@
> >  #include <linux/init.h>
> >  #include <linux/iommu.h>
> >  #include <linux/kernel.h>
> > +#include <linux/pci.h>
> >
> >  #include "iommu-bits.h"
> >  #include "iommu.h"
> > @@ -36,6 +37,60 @@ static void riscv_iommu_disable(struct riscv_iommu_device *iommu)
> >         riscv_iommu_writel(iommu, RISCV_IOMMU_REG_PQCSR, 0);
> >  }
> >
> > +static int riscv_iommu_attach_identity_domain(struct iommu_domain *iommu_domain,
> > +                                             struct device *dev)
> > +{
> > +       /* Global pass-through already enabled, do nothing for now. */
> > +       return 0;
> > +}
> > +
> > +static struct iommu_domain riscv_iommu_identity_domain = {
> > +       .type = IOMMU_DOMAIN_IDENTITY,
> > +       .ops = &(const struct iommu_domain_ops) {
> > +               .attach_dev = riscv_iommu_attach_identity_domain,
> > +       }
> > +};
> > +
> > +static int riscv_iommu_device_domain_type(struct device *dev)
> > +{
> > +       return IOMMU_DOMAIN_IDENTITY;
> > +}
> > +
> > +static struct iommu_group *riscv_iommu_device_group(struct device *dev)
> > +{
> > +       if (dev_is_pci(dev))
> > +               return pci_device_group(dev);
> > +       return generic_device_group(dev);
> > +}
> > +
> > +static int riscv_iommu_of_xlate(struct device *dev, const struct of_phandle_args *args)
> > +{
> > +       return iommu_fwspec_add_ids(dev, args->args, 1);
> > +}
> > +
> > +static struct iommu_device *riscv_iommu_probe_device(struct device *dev)
> > +{
> > +       struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> > +       struct riscv_iommu_device *iommu;
> > +
> > +       if (!fwspec->iommu_fwnode->dev || !fwspec->num_ids)
> > +               return ERR_PTR(-ENODEV);
>
> It seems to me that we might need to ensure fwspec is not NULL before
> accessing fwspec->iommu_fwnode, otherwise, it will cause NULL pointer
> dereference.
>

Thank you. Fix applied to v5.

> > +
> > +       iommu = dev_get_drvdata(fwspec->iommu_fwnode->dev);
> > +       if (!iommu)
> > +               return ERR_PTR(-ENODEV);
> > +
> > +       return &iommu->iommu;
> > +}
> > +
> > +static const struct iommu_ops riscv_iommu_ops = {
> > +       .of_xlate = riscv_iommu_of_xlate,
> > +       .identity_domain = &riscv_iommu_identity_domain,
> > +       .def_domain_type = riscv_iommu_device_domain_type,
> > +       .device_group = riscv_iommu_device_group,
> > +       .probe_device = riscv_iommu_probe_device,
> > +};
> > +
> >  static int riscv_iommu_init_check(struct riscv_iommu_device *iommu)
> >  {
> >         u64 ddtp;
> > @@ -71,6 +126,7 @@ static int riscv_iommu_init_check(struct riscv_iommu_device *iommu)
> >
> >  void riscv_iommu_remove(struct riscv_iommu_device *iommu)
> >  {
> > +       iommu_device_unregister(&iommu->iommu);
> >         iommu_device_sysfs_remove(&iommu->iommu);
> >  }
> >
> > @@ -95,5 +151,15 @@ int riscv_iommu_init(struct riscv_iommu_device *iommu)
> >                 return dev_err_probe(iommu->dev, rc,
> >                                      "cannot register sysfs interface\n");
> >
> > +       rc = iommu_device_register(&iommu->iommu, &riscv_iommu_ops, iommu->dev);
> > +       if (rc) {
> > +               dev_err_probe(iommu->dev, rc, "cannot register iommu interface\n");
> > +               goto err_remove_sysfs;
> > +       }
> > +
> >         return 0;
> > +
> > +err_remove_sysfs:
> > +       iommu_device_sysfs_remove(&iommu->iommu);
> > +       return rc;
> >  }
> > --
> > 2.34.1
> >
> >

Best,
- Tomasz

> > _______________________________________________
> > linux-riscv mailing list
> > linux-riscv@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-riscv

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