Patchwork [RFC,v3,06/21] vfio: VFIO_IOMMU_BIND_MSI

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Submitter Auger Eric
Date Jan. 8, 2019, 10:26 a.m.
Message ID <20190108102633.17482-7-eric.auger@redhat.com>
Download mbox | patch
Permalink /patch/694569/
State New
Headers show

Comments

Auger Eric - Jan. 8, 2019, 10:26 a.m.
This patch adds the VFIO_IOMMU_BIND_MSI ioctl which aims at
passing the guest MSI binding to the host.

Signed-off-by: Eric Auger <eric.auger@redhat.com>

---

v2 -> v3:
- adapt to new proto of bind_guest_msi
- directly use vfio_iommu_for_each_dev

v1 -> v2:
- s/vfio_iommu_type1_guest_msi_binding/vfio_iommu_type1_bind_guest_msi
---
 drivers/vfio/vfio_iommu_type1.c | 27 +++++++++++++++++++++++++++
 include/uapi/linux/vfio.h       |  7 +++++++
 2 files changed, 34 insertions(+)
Alex Williamson - Jan. 11, 2019, 11:02 p.m.
On Tue,  8 Jan 2019 11:26:18 +0100
Eric Auger <eric.auger@redhat.com> wrote:

> This patch adds the VFIO_IOMMU_BIND_MSI ioctl which aims at
> passing the guest MSI binding to the host.
> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> 
> ---
> 
> v2 -> v3:
> - adapt to new proto of bind_guest_msi
> - directly use vfio_iommu_for_each_dev
> 
> v1 -> v2:
> - s/vfio_iommu_type1_guest_msi_binding/vfio_iommu_type1_bind_guest_msi
> ---
>  drivers/vfio/vfio_iommu_type1.c | 27 +++++++++++++++++++++++++++
>  include/uapi/linux/vfio.h       |  7 +++++++
>  2 files changed, 34 insertions(+)
> 
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index c3ba3f249438..59229f6e2d84 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -1673,6 +1673,15 @@ static int vfio_cache_inv_fn(struct device *dev, void *data)
>  	return iommu_cache_invalidate(d, dev, &ustruct->info);
>  }
>  
> +static int vfio_bind_guest_msi_fn(struct device *dev, void *data)
> +{
> +	struct vfio_iommu_type1_bind_guest_msi *ustruct =
> +		(struct vfio_iommu_type1_bind_guest_msi *)data;
> +	struct iommu_domain *d = iommu_get_domain_for_dev(dev);
> +
> +	return iommu_bind_guest_msi(d, dev, &ustruct->binding);
> +}
> +
>  static int
>  vfio_set_pasid_table(struct vfio_iommu *iommu,
>  		      struct vfio_iommu_type1_set_pasid_table *ustruct)
> @@ -1792,6 +1801,24 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
>  					      vfio_cache_inv_fn);
>  		mutex_unlock(&iommu->lock);
>  		return ret;
> +	} else if (cmd == VFIO_IOMMU_BIND_MSI) {
> +		struct vfio_iommu_type1_bind_guest_msi ustruct;
> +		int ret;
> +
> +		minsz = offsetofend(struct vfio_iommu_type1_bind_guest_msi,
> +				    binding);
> +
> +		if (copy_from_user(&ustruct, (void __user *)arg, minsz))
> +			return -EFAULT;
> +
> +		if (ustruct.argsz < minsz || ustruct.flags)
> +			return -EINVAL;
> +
> +		mutex_lock(&iommu->lock);
> +		ret = vfio_iommu_for_each_dev(iommu, &ustruct,
> +					      vfio_bind_guest_msi_fn);

The vfio_iommu_for_each_dev() interface is fine for invalidation, where
a partial failure requires no unwind, but it's not sufficiently robust
here.

> +		mutex_unlock(&iommu->lock);
> +		return ret;
>  	}
>  
>  	return -ENOTTY;
> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> index 11a07165e7e1..352e795a93c8 100644
> --- a/include/uapi/linux/vfio.h
> +++ b/include/uapi/linux/vfio.h
> @@ -774,6 +774,13 @@ struct vfio_iommu_type1_cache_invalidate {
>  };
>  #define VFIO_IOMMU_CACHE_INVALIDATE      _IO(VFIO_TYPE, VFIO_BASE + 23)
>  
> +struct vfio_iommu_type1_bind_guest_msi {
> +	__u32   argsz;
> +	__u32   flags;
> +	struct iommu_guest_msi_binding binding;
> +};
> +#define VFIO_IOMMU_BIND_MSI      _IO(VFIO_TYPE, VFIO_BASE + 24)

-ENOCOMMENTS  MSIs are setup and torn down, is this only a machine init
sort of interface?  How does the user un-bind?  Thanks,

Alex

> +
>  /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */
>  
>  /*
Alex Williamson - Jan. 11, 2019, 11:23 p.m.
On Fri, 11 Jan 2019 16:02:44 -0700
Alex Williamson <alex.williamson@redhat.com> wrote:

> On Tue,  8 Jan 2019 11:26:18 +0100
> Eric Auger <eric.auger@redhat.com> wrote:
> 
> > This patch adds the VFIO_IOMMU_BIND_MSI ioctl which aims at
> > passing the guest MSI binding to the host.
> > 
> > Signed-off-by: Eric Auger <eric.auger@redhat.com>
> > 
> > ---
> > 
> > v2 -> v3:
> > - adapt to new proto of bind_guest_msi
> > - directly use vfio_iommu_for_each_dev
> > 
> > v1 -> v2:
> > - s/vfio_iommu_type1_guest_msi_binding/vfio_iommu_type1_bind_guest_msi
> > ---
> >  drivers/vfio/vfio_iommu_type1.c | 27 +++++++++++++++++++++++++++
> >  include/uapi/linux/vfio.h       |  7 +++++++
> >  2 files changed, 34 insertions(+)
> > 
> > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> > index c3ba3f249438..59229f6e2d84 100644
> > --- a/drivers/vfio/vfio_iommu_type1.c
> > +++ b/drivers/vfio/vfio_iommu_type1.c
> > @@ -1673,6 +1673,15 @@ static int vfio_cache_inv_fn(struct device *dev, void *data)
> >  	return iommu_cache_invalidate(d, dev, &ustruct->info);
> >  }
> >  
> > +static int vfio_bind_guest_msi_fn(struct device *dev, void *data)
> > +{
> > +	struct vfio_iommu_type1_bind_guest_msi *ustruct =
> > +		(struct vfio_iommu_type1_bind_guest_msi *)data;
> > +	struct iommu_domain *d = iommu_get_domain_for_dev(dev);
> > +
> > +	return iommu_bind_guest_msi(d, dev, &ustruct->binding);
> > +}
> > +
> >  static int
> >  vfio_set_pasid_table(struct vfio_iommu *iommu,
> >  		      struct vfio_iommu_type1_set_pasid_table *ustruct)
> > @@ -1792,6 +1801,24 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
> >  					      vfio_cache_inv_fn);
> >  		mutex_unlock(&iommu->lock);
> >  		return ret;
> > +	} else if (cmd == VFIO_IOMMU_BIND_MSI) {
> > +		struct vfio_iommu_type1_bind_guest_msi ustruct;
> > +		int ret;
> > +
> > +		minsz = offsetofend(struct vfio_iommu_type1_bind_guest_msi,
> > +				    binding);
> > +
> > +		if (copy_from_user(&ustruct, (void __user *)arg, minsz))
> > +			return -EFAULT;
> > +
> > +		if (ustruct.argsz < minsz || ustruct.flags)
> > +			return -EINVAL;
> > +
> > +		mutex_lock(&iommu->lock);
> > +		ret = vfio_iommu_for_each_dev(iommu, &ustruct,
> > +					      vfio_bind_guest_msi_fn);  
> 
> The vfio_iommu_for_each_dev() interface is fine for invalidation, where
> a partial failure requires no unwind, but it's not sufficiently robust
> here.

Additionally, what happens as devices are added and removed from the
guest?  Are we designing an interface that specifically precludes
hotplug?  Thanks,

Alex
 
> > +		mutex_unlock(&iommu->lock);
> > +		return ret;
> >  	}
> >  
> >  	return -ENOTTY;
> > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> > index 11a07165e7e1..352e795a93c8 100644
> > --- a/include/uapi/linux/vfio.h
> > +++ b/include/uapi/linux/vfio.h
> > @@ -774,6 +774,13 @@ struct vfio_iommu_type1_cache_invalidate {
> >  };
> >  #define VFIO_IOMMU_CACHE_INVALIDATE      _IO(VFIO_TYPE, VFIO_BASE + 23)
> >  
> > +struct vfio_iommu_type1_bind_guest_msi {
> > +	__u32   argsz;
> > +	__u32   flags;
> > +	struct iommu_guest_msi_binding binding;
> > +};
> > +#define VFIO_IOMMU_BIND_MSI      _IO(VFIO_TYPE, VFIO_BASE + 24)  
> 
> -ENOCOMMENTS  MSIs are setup and torn down, is this only a machine init
> sort of interface?  How does the user un-bind?  Thanks,
> 
> Alex
> 
> > +
> >  /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */
> >  
> >  /*  
>

Patch

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index c3ba3f249438..59229f6e2d84 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -1673,6 +1673,15 @@  static int vfio_cache_inv_fn(struct device *dev, void *data)
 	return iommu_cache_invalidate(d, dev, &ustruct->info);
 }
 
+static int vfio_bind_guest_msi_fn(struct device *dev, void *data)
+{
+	struct vfio_iommu_type1_bind_guest_msi *ustruct =
+		(struct vfio_iommu_type1_bind_guest_msi *)data;
+	struct iommu_domain *d = iommu_get_domain_for_dev(dev);
+
+	return iommu_bind_guest_msi(d, dev, &ustruct->binding);
+}
+
 static int
 vfio_set_pasid_table(struct vfio_iommu *iommu,
 		      struct vfio_iommu_type1_set_pasid_table *ustruct)
@@ -1792,6 +1801,24 @@  static long vfio_iommu_type1_ioctl(void *iommu_data,
 					      vfio_cache_inv_fn);
 		mutex_unlock(&iommu->lock);
 		return ret;
+	} else if (cmd == VFIO_IOMMU_BIND_MSI) {
+		struct vfio_iommu_type1_bind_guest_msi ustruct;
+		int ret;
+
+		minsz = offsetofend(struct vfio_iommu_type1_bind_guest_msi,
+				    binding);
+
+		if (copy_from_user(&ustruct, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (ustruct.argsz < minsz || ustruct.flags)
+			return -EINVAL;
+
+		mutex_lock(&iommu->lock);
+		ret = vfio_iommu_for_each_dev(iommu, &ustruct,
+					      vfio_bind_guest_msi_fn);
+		mutex_unlock(&iommu->lock);
+		return ret;
 	}
 
 	return -ENOTTY;
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 11a07165e7e1..352e795a93c8 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -774,6 +774,13 @@  struct vfio_iommu_type1_cache_invalidate {
 };
 #define VFIO_IOMMU_CACHE_INVALIDATE      _IO(VFIO_TYPE, VFIO_BASE + 23)
 
+struct vfio_iommu_type1_bind_guest_msi {
+	__u32   argsz;
+	__u32   flags;
+	struct iommu_guest_msi_binding binding;
+};
+#define VFIO_IOMMU_BIND_MSI      _IO(VFIO_TYPE, VFIO_BASE + 24)
+
 /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */
 
 /*