RE: [PATCH v5 11/15] vfio/type1: Allow invalidating first-level/stage IOMMU cache
Hi Eric,
> From: Auger Eric
> Sent: Monday, July 20, 2020 5:42 PM
>
> Yi,
>
> On 7/12/20 1:21 PM, Liu Yi L wrote:
> > This patch provides an interface allowing the userspace to invalidate
> > IOMMU cache for first-level page table. It is required when the first
> > level IOMMU page table is not managed by the host kernel in the nested
> > translation setup.
> >
> > Cc: Kevin Tian
> > CC: Jacob Pan
> > Cc: Alex Williamson
> > Cc: Eric Auger
> > Cc: Jean-Philippe Brucker
> > Cc: Joerg Roedel
> > Cc: Lu Baolu
> > Signed-off-by: Liu Yi L
> > Signed-off-by: Eric Auger
> > Signed-off-by: Jacob Pan
> > ---
> > v1 -> v2:
> > *) rename from "vfio/type1: Flush stage-1 IOMMU cache for nesting type"
> > *) rename vfio_cache_inv_fn() to vfio_dev_cache_invalidate_fn()
> > *) vfio_dev_cache_inv_fn() always successful
> > *) remove VFIO_IOMMU_CACHE_INVALIDATE, and reuse
> VFIO_IOMMU_NESTING_OP
> > ---
> > drivers/vfio/vfio_iommu_type1.c | 50
> +
> > include/uapi/linux/vfio.h | 3 +++
> > 2 files changed, 53 insertions(+)
> >
> > diff --git a/drivers/vfio/vfio_iommu_type1.c
> > b/drivers/vfio/vfio_iommu_type1.c
> > index f0f21ff..960cc59 100644
> > --- a/drivers/vfio/vfio_iommu_type1.c
> > +++ b/drivers/vfio/vfio_iommu_type1.c
> > @@ -3073,6 +3073,53 @@ static long vfio_iommu_handle_pgtbl_op(struct
> vfio_iommu *iommu,
> > return ret;
> > }
> >
> > +static int vfio_dev_cache_invalidate_fn(struct device *dev, void *data)
> > +{
> > + struct domain_capsule *dc = (struct domain_capsule *)data;
> > + unsigned long arg = *(unsigned long *)dc->data;
> > +
> > + iommu_cache_invalidate(dc->domain, dev, (void __user *)arg);
> > + return 0;
> > +}
> > +
> > +static long vfio_iommu_invalidate_cache(struct vfio_iommu *iommu,
> > + unsigned long arg)
> > +{
> > + struct domain_capsule dc = { .data = };
> > + struct vfio_group *group;
> > + struct vfio_domain *domain;
> > + int ret = 0;
> > + struct iommu_nesting_info *info;
> > +
> > + mutex_lock(>lock);
> > + /*
> > +* Cache invalidation is required for any nesting IOMMU,
> > +* so no need to check system-wide PASID support.
> > +*/
> > + info = iommu->nesting_info;
> > + if (!info || !(info->features & IOMMU_NESTING_FEAT_CACHE_INVLD)) {
> > + ret = -EOPNOTSUPP;
> > + goto out_unlock;
> > + }
> > +
> > + group = vfio_find_nesting_group(iommu);
> so I see you reuse it here. But still wondering if you cant't directly
> set dc.domain and dc.group group below using list_firt_entry?
I guess yes for current implementation. I also considered if I can
get a helper function to retrun a dc with group and domain field
initialized as it is common code used by both bind/unbind and cache_inv
path. perhaps something like get_domain_capsule_for_nesting()
> > + if (!group) {
> > + ret = -EINVAL;
> > + goto out_unlock;
> > + }
> > +
> > + domain = list_first_entry(>domain_list,
> > + struct vfio_domain, next);
> > + dc.group = group;
> > + dc.domain = domain->domain;
> > + iommu_group_for_each_dev(group->iommu_group, ,
> > +vfio_dev_cache_invalidate_fn);
> > +
> > +out_unlock:
> > + mutex_unlock(>lock);
> > + return ret;
> > +}
> > +
> > static long vfio_iommu_type1_nesting_op(struct vfio_iommu *iommu,
> > unsigned long arg)
> > {
> > @@ -3095,6 +3142,9 @@ static long vfio_iommu_type1_nesting_op(struct
> vfio_iommu *iommu,
> > case VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL:
> > ret = vfio_iommu_handle_pgtbl_op(iommu, false, arg + minsz);
> > break;
> > + case VFIO_IOMMU_NESTING_OP_CACHE_INVLD:
> > + ret = vfio_iommu_invalidate_cache(iommu, arg + minsz);
> > + break;
> > default:
> > ret = -EINVAL;
> > }
> > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> > index a8ad786..845a5800 100644
> > --- a/include/uapi/linux/vfio.h
> > +++ b/include/uapi/linux/vfio.h
> > @@ -1225,6 +1225,8 @@ struct vfio_iommu_type1_pasid_request {
> > * +-+---+
> > * | UNBIND_PGTBL| struct iommu_gpasid_bind_data|
> > * +-+---+
> > + * | CACHE_INVLD | struct iommu_cache_invalidate_info |
> > + * +-+---+
> > *
> > * returns: 0 on success, -errno on failure.
> > */
> > @@ -1237,6 +1239,7 @@ struct vfio_iommu_type1_nesting_op {
> >
> > #define VFIO_IOMMU_NESTING_OP_BIND_PGTBL (0)
> > #define VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL (1)
> > +#define VFIO_IOMMU_NESTING_OP_CACHE_INVLD (2)
> >
> > #define VFIO_IOMMU_NESTING_OP _IO(VFIO_TYPE, VFIO_BASE + 19)
> >
> >
> Otherwise looks good to me
thanks,
Regards,
Yi Liu
>
Re: [PATCH v5 11/15] vfio/type1: Allow invalidating first-level/stage IOMMU cache
Yi,
On 7/12/20 1:21 PM, Liu Yi L wrote:
> This patch provides an interface allowing the userspace to invalidate
> IOMMU cache for first-level page table. It is required when the first
> level IOMMU page table is not managed by the host kernel in the nested
> translation setup.
>
> Cc: Kevin Tian
> CC: Jacob Pan
> Cc: Alex Williamson
> Cc: Eric Auger
> Cc: Jean-Philippe Brucker
> Cc: Joerg Roedel
> Cc: Lu Baolu
> Signed-off-by: Liu Yi L
> Signed-off-by: Eric Auger
> Signed-off-by: Jacob Pan
> ---
> v1 -> v2:
> *) rename from "vfio/type1: Flush stage-1 IOMMU cache for nesting type"
> *) rename vfio_cache_inv_fn() to vfio_dev_cache_invalidate_fn()
> *) vfio_dev_cache_inv_fn() always successful
> *) remove VFIO_IOMMU_CACHE_INVALIDATE, and reuse VFIO_IOMMU_NESTING_OP
> ---
> drivers/vfio/vfio_iommu_type1.c | 50
> +
> include/uapi/linux/vfio.h | 3 +++
> 2 files changed, 53 insertions(+)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index f0f21ff..960cc59 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -3073,6 +3073,53 @@ static long vfio_iommu_handle_pgtbl_op(struct
> vfio_iommu *iommu,
> return ret;
> }
>
> +static int vfio_dev_cache_invalidate_fn(struct device *dev, void *data)
> +{
> + struct domain_capsule *dc = (struct domain_capsule *)data;
> + unsigned long arg = *(unsigned long *)dc->data;
> +
> + iommu_cache_invalidate(dc->domain, dev, (void __user *)arg);
> + return 0;
> +}
> +
> +static long vfio_iommu_invalidate_cache(struct vfio_iommu *iommu,
> + unsigned long arg)
> +{
> + struct domain_capsule dc = { .data = };
> + struct vfio_group *group;
> + struct vfio_domain *domain;
> + int ret = 0;
> + struct iommu_nesting_info *info;
> +
> + mutex_lock(>lock);
> + /*
> + * Cache invalidation is required for any nesting IOMMU,
> + * so no need to check system-wide PASID support.
> + */
> + info = iommu->nesting_info;
> + if (!info || !(info->features & IOMMU_NESTING_FEAT_CACHE_INVLD)) {
> + ret = -EOPNOTSUPP;
> + goto out_unlock;
> + }
> +
> + group = vfio_find_nesting_group(iommu);
so I see you reuse it here. But still wondering if you cant't directly
set dc.domain and dc.group group below using list_firt_entry?
> + if (!group) {
> + ret = -EINVAL;
> + goto out_unlock;
> + }
> +
> + domain = list_first_entry(>domain_list,
> + struct vfio_domain, next);
> + dc.group = group;
> + dc.domain = domain->domain;
> + iommu_group_for_each_dev(group->iommu_group, ,
> + vfio_dev_cache_invalidate_fn);
> +
> +out_unlock:
> + mutex_unlock(>lock);
> + return ret;
> +}
> +
> static long vfio_iommu_type1_nesting_op(struct vfio_iommu *iommu,
> unsigned long arg)
> {
> @@ -3095,6 +3142,9 @@ static long vfio_iommu_type1_nesting_op(struct
> vfio_iommu *iommu,
> case VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL:
> ret = vfio_iommu_handle_pgtbl_op(iommu, false, arg + minsz);
> break;
> + case VFIO_IOMMU_NESTING_OP_CACHE_INVLD:
> + ret = vfio_iommu_invalidate_cache(iommu, arg + minsz);
> + break;
> default:
> ret = -EINVAL;
> }
> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> index a8ad786..845a5800 100644
> --- a/include/uapi/linux/vfio.h
> +++ b/include/uapi/linux/vfio.h
> @@ -1225,6 +1225,8 @@ struct vfio_iommu_type1_pasid_request {
> * +-+---+
> * | UNBIND_PGTBL| struct iommu_gpasid_bind_data|
> * +-+---+
> + * | CACHE_INVLD | struct iommu_cache_invalidate_info |
> + * +-+---+
> *
> * returns: 0 on success, -errno on failure.
> */
> @@ -1237,6 +1239,7 @@ struct vfio_iommu_type1_nesting_op {
>
> #define VFIO_IOMMU_NESTING_OP_BIND_PGTBL (0)
> #define VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL (1)
> +#define VFIO_IOMMU_NESTING_OP_CACHE_INVLD(2)
>
> #define VFIO_IOMMU_NESTING_OP_IO(VFIO_TYPE, VFIO_BASE + 19)
>
>
Otherwise looks good to me
Thanks
Eric
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[PATCH v5 11/15] vfio/type1: Allow invalidating first-level/stage IOMMU cache
This patch provides an interface allowing the userspace to invalidate
IOMMU cache for first-level page table. It is required when the first
level IOMMU page table is not managed by the host kernel in the nested
translation setup.
Cc: Kevin Tian
CC: Jacob Pan
Cc: Alex Williamson
Cc: Eric Auger
Cc: Jean-Philippe Brucker
Cc: Joerg Roedel
Cc: Lu Baolu
Signed-off-by: Liu Yi L
Signed-off-by: Eric Auger
Signed-off-by: Jacob Pan
---
v1 -> v2:
*) rename from "vfio/type1: Flush stage-1 IOMMU cache for nesting type"
*) rename vfio_cache_inv_fn() to vfio_dev_cache_invalidate_fn()
*) vfio_dev_cache_inv_fn() always successful
*) remove VFIO_IOMMU_CACHE_INVALIDATE, and reuse VFIO_IOMMU_NESTING_OP
---
drivers/vfio/vfio_iommu_type1.c | 50 +
include/uapi/linux/vfio.h | 3 +++
2 files changed, 53 insertions(+)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index f0f21ff..960cc59 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -3073,6 +3073,53 @@ static long vfio_iommu_handle_pgtbl_op(struct vfio_iommu
*iommu,
return ret;
}
+static int vfio_dev_cache_invalidate_fn(struct device *dev, void *data)
+{
+ struct domain_capsule *dc = (struct domain_capsule *)data;
+ unsigned long arg = *(unsigned long *)dc->data;
+
+ iommu_cache_invalidate(dc->domain, dev, (void __user *)arg);
+ return 0;
+}
+
+static long vfio_iommu_invalidate_cache(struct vfio_iommu *iommu,
+ unsigned long arg)
+{
+ struct domain_capsule dc = { .data = };
+ struct vfio_group *group;
+ struct vfio_domain *domain;
+ int ret = 0;
+ struct iommu_nesting_info *info;
+
+ mutex_lock(>lock);
+ /*
+* Cache invalidation is required for any nesting IOMMU,
+* so no need to check system-wide PASID support.
+*/
+ info = iommu->nesting_info;
+ if (!info || !(info->features & IOMMU_NESTING_FEAT_CACHE_INVLD)) {
+ ret = -EOPNOTSUPP;
+ goto out_unlock;
+ }
+
+ group = vfio_find_nesting_group(iommu);
+ if (!group) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ domain = list_first_entry(>domain_list,
+ struct vfio_domain, next);
+ dc.group = group;
+ dc.domain = domain->domain;
+ iommu_group_for_each_dev(group->iommu_group, ,
+vfio_dev_cache_invalidate_fn);
+
+out_unlock:
+ mutex_unlock(>lock);
+ return ret;
+}
+
static long vfio_iommu_type1_nesting_op(struct vfio_iommu *iommu,
unsigned long arg)
{
@@ -3095,6 +3142,9 @@ static long vfio_iommu_type1_nesting_op(struct vfio_iommu
*iommu,
case VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL:
ret = vfio_iommu_handle_pgtbl_op(iommu, false, arg + minsz);
break;
+ case VFIO_IOMMU_NESTING_OP_CACHE_INVLD:
+ ret = vfio_iommu_invalidate_cache(iommu, arg + minsz);
+ break;
default:
ret = -EINVAL;
}
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index a8ad786..845a5800 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -1225,6 +1225,8 @@ struct vfio_iommu_type1_pasid_request {
* +-+---+
* | UNBIND_PGTBL| struct iommu_gpasid_bind_data|
* +-+---+
+ * | CACHE_INVLD | struct iommu_cache_invalidate_info |
+ * +-+---+
*
* returns: 0 on success, -errno on failure.
*/
@@ -1237,6 +1239,7 @@ struct vfio_iommu_type1_nesting_op {
#define VFIO_IOMMU_NESTING_OP_BIND_PGTBL (0)
#define VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL (1)
+#define VFIO_IOMMU_NESTING_OP_CACHE_INVLD (2)
#define VFIO_IOMMU_NESTING_OP _IO(VFIO_TYPE, VFIO_BASE + 19)
--
2.7.4
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