| Message ID | 1594552870-55687-8-git-send-email-yi.l.liu@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vfio: expose virtual Shared Virtual Addressing to VMs | expand |
Yi, On 7/12/20 1:21 PM, Liu Yi L wrote: > This patch allows user space to request PASID allocation/free, e.g. when > serving the request from the guest. > > PASIDs that are not freed by userspace are automatically freed when the > IOASID set is destroyed when process exits. > > Cc: Kevin Tian <kevin.tian@intel.com> > CC: Jacob Pan <jacob.jun.pan@linux.intel.com> > Cc: Alex Williamson <alex.williamson@redhat.com> > Cc: Eric Auger <eric.auger@redhat.com> > Cc: Jean-Philippe Brucker <jean-philippe@linaro.org> > Cc: Joerg Roedel <joro@8bytes.org> > Cc: Lu Baolu <baolu.lu@linux.intel.com> > Signed-off-by: Liu Yi L <yi.l.liu@intel.com> > Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com> > Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> > --- > v4 -> v5: > *) address comments from Eric Auger. > *) the comments for the PASID_FREE request is addressed in patch 5/15 of > this series. > > v3 -> v4: > *) address comments from v3, except the below comment against the range > of PASID_FREE request. needs more help on it. > "> +if (req.range.min > req.range.max) > > Is it exploitable that a user can spin the kernel for a long time in > the case of a free by calling this with [0, MAX_UINT] regardless of > their actual allocations?" > https://lore.kernel.org/linux-iommu/20200702151832.048b44d1@x1.home/ > > v1 -> v2: > *) move the vfio_mm related code to be a seprate module > *) use a single structure for alloc/free, could support a range of PASIDs > *) fetch vfio_mm at group_attach time instead of at iommu driver open time > --- > drivers/vfio/Kconfig | 1 + > drivers/vfio/vfio_iommu_type1.c | 85 +++++++++++++++++++++++++++++++++++++++++ > drivers/vfio/vfio_pasid.c | 10 +++++ > include/linux/vfio.h | 6 +++ > include/uapi/linux/vfio.h | 37 ++++++++++++++++++ > 5 files changed, 139 insertions(+) > > diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig > index 3d8a108..95d90c6 100644 > --- a/drivers/vfio/Kconfig > +++ b/drivers/vfio/Kconfig > @@ -2,6 +2,7 @@ > config VFIO_IOMMU_TYPE1 > tristate > depends on VFIO > + select VFIO_PASID if (X86) > default n > > config VFIO_IOMMU_SPAPR_TCE > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c > index ed80104..55b4065 100644 > --- a/drivers/vfio/vfio_iommu_type1.c > +++ b/drivers/vfio/vfio_iommu_type1.c > @@ -76,6 +76,7 @@ struct vfio_iommu { > bool dirty_page_tracking; > bool pinned_page_dirty_scope; > struct iommu_nesting_info *nesting_info; > + struct vfio_mm *vmm; > }; > > struct vfio_domain { > @@ -1937,6 +1938,11 @@ static void vfio_iommu_iova_insert_copy(struct vfio_iommu *iommu, > > static void vfio_iommu_release_nesting_info(struct vfio_iommu *iommu) > { > + if (iommu->vmm) { > + vfio_mm_put(iommu->vmm); > + iommu->vmm = NULL; > + } > + > kfree(iommu->nesting_info); > iommu->nesting_info = NULL; > } > @@ -2071,6 +2077,26 @@ static int vfio_iommu_type1_attach_group(void *iommu_data, > iommu->nesting_info); > if (ret) > goto out_detach; > + > + if (iommu->nesting_info->features & > + IOMMU_NESTING_FEAT_SYSWIDE_PASID) { > + struct vfio_mm *vmm; > + int sid; > + > + vmm = vfio_mm_get_from_task(current); > + if (IS_ERR(vmm)) { > + ret = PTR_ERR(vmm); > + goto out_detach; > + } > + iommu->vmm = vmm; > + > + sid = vfio_mm_ioasid_sid(vmm); > + ret = iommu_domain_set_attr(domain->domain, > + DOMAIN_ATTR_IOASID_SID, > + &sid); > + if (ret) > + goto out_detach; > + } > } > > /* Get aperture info */ > @@ -2855,6 +2881,63 @@ static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu, > return -EINVAL; > } > > +static int vfio_iommu_type1_pasid_alloc(struct vfio_iommu *iommu, > + unsigned int min, > + unsigned int max) > +{ > + int ret = -EOPNOTSUPP; > + > + mutex_lock(&iommu->lock); > + if (iommu->vmm) > + ret = vfio_pasid_alloc(iommu->vmm, min, max); > + mutex_unlock(&iommu->lock); > + return ret; > +} > + > +static int vfio_iommu_type1_pasid_free(struct vfio_iommu *iommu, > + unsigned int min, > + unsigned int max) > +{ > + int ret = -EOPNOTSUPP; > + > + mutex_lock(&iommu->lock); > + if (iommu->vmm) { > + vfio_pasid_free_range(iommu->vmm, min, max); > + ret = 0; > + } > + mutex_unlock(&iommu->lock); > + return ret; > +} > + > +static int vfio_iommu_type1_pasid_request(struct vfio_iommu *iommu, > + unsigned long arg) > +{ > + struct vfio_iommu_type1_pasid_request req; > + unsigned long minsz; > + > + minsz = offsetofend(struct vfio_iommu_type1_pasid_request, range); > + > + if (copy_from_user(&req, (void __user *)arg, minsz)) > + return -EFAULT; > + > + if (req.argsz < minsz || (req.flags & ~VFIO_PASID_REQUEST_MASK)) > + return -EINVAL; > + > + if (req.range.min > req.range.max) > + return -EINVAL; > + > + switch (req.flags & VFIO_PASID_REQUEST_MASK) { > + case VFIO_IOMMU_FLAG_ALLOC_PASID:not sure it is worth to introduce both vfio_iommu_type1_pasid_free/alloc helpers. You could take the lock above, and test iommu->vmm as well above. > + return vfio_iommu_type1_pasid_alloc(iommu, > + req.range.min, req.range.max); > + case VFIO_IOMMU_FLAG_FREE_PASID: > + return vfio_iommu_type1_pasid_free(iommu, > + req.range.min, req.range.max); > + default: > + return -EINVAL; > + } > +} > + > static long vfio_iommu_type1_ioctl(void *iommu_data, > unsigned int cmd, unsigned long arg) > { > @@ -2871,6 +2954,8 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, > return vfio_iommu_type1_unmap_dma(iommu, arg); > case VFIO_IOMMU_DIRTY_PAGES: > return vfio_iommu_type1_dirty_pages(iommu, arg); > + case VFIO_IOMMU_PASID_REQUEST: > + return vfio_iommu_type1_pasid_request(iommu, arg); > default: > return -ENOTTY; > } > diff --git a/drivers/vfio/vfio_pasid.c b/drivers/vfio/vfio_pasid.c > index 66e6054e..ebec244 100644 > --- a/drivers/vfio/vfio_pasid.c > +++ b/drivers/vfio/vfio_pasid.c > @@ -61,6 +61,7 @@ void vfio_mm_put(struct vfio_mm *vmm) > { > kref_put_mutex(&vmm->kref, vfio_mm_release, &vfio_mm_lock); > } > +EXPORT_SYMBOL_GPL(vfio_mm_put); > > static void vfio_mm_get(struct vfio_mm *vmm) > { > @@ -114,6 +115,13 @@ struct vfio_mm *vfio_mm_get_from_task(struct task_struct *task) > mmput(mm); > return vmm; > } > +EXPORT_SYMBOL_GPL(vfio_mm_get_from_task); > + > +int vfio_mm_ioasid_sid(struct vfio_mm *vmm) > +{ > + return vmm->ioasid_sid; > +} > +EXPORT_SYMBOL_GPL(vfio_mm_ioasid_sid); > > /* > * Find PASID within @min and @max > @@ -197,6 +205,7 @@ int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max) > > return pasid; > } > +EXPORT_SYMBOL_GPL(vfio_pasid_alloc); > > void vfio_pasid_free_range(struct vfio_mm *vmm, > ioasid_t min, ioasid_t max) > @@ -213,6 +222,7 @@ void vfio_pasid_free_range(struct vfio_mm *vmm, > vfio_remove_pasid(vmm, vid); > mutex_unlock(&vmm->pasid_lock); > } > +EXPORT_SYMBOL_GPL(vfio_pasid_free_range); > > static int __init vfio_pasid_init(void) > { > diff --git a/include/linux/vfio.h b/include/linux/vfio.h > index 31472a9..a111108 100644 > --- a/include/linux/vfio.h > +++ b/include/linux/vfio.h > @@ -101,6 +101,7 @@ struct vfio_mm; > #if IS_ENABLED(CONFIG_VFIO_PASID) > extern struct vfio_mm *vfio_mm_get_from_task(struct task_struct *task); > extern void vfio_mm_put(struct vfio_mm *vmm); > +int vfio_mm_ioasid_sid(struct vfio_mm *vmm); I still don't get why it does not take an extern as the other functions implemented in vfio_pasid.c and used in other modules. what's the difference? > extern int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max); > extern void vfio_pasid_free_range(struct vfio_mm *vmm, > ioasid_t min, ioasid_t max); > @@ -114,6 +115,11 @@ static inline void vfio_mm_put(struct vfio_mm *vmm) > { > } > > +static inline int vfio_mm_ioasid_sid(struct vfio_mm *vmm) > +{ > + return -ENOTTY; > +} > + > static inline int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max) > { > return -ENOTTY; > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h > index 46a78af..96a115f 100644 > --- a/include/uapi/linux/vfio.h > +++ b/include/uapi/linux/vfio.h > @@ -1172,6 +1172,43 @@ struct vfio_iommu_type1_dirty_bitmap_get { > > #define VFIO_IOMMU_DIRTY_PAGES _IO(VFIO_TYPE, VFIO_BASE + 17) > > +/** > + * VFIO_IOMMU_PASID_REQUEST - _IOWR(VFIO_TYPE, VFIO_BASE + 18, > + * struct vfio_iommu_type1_pasid_request) > + * > + * PASID (Processor Address Space ID) is a PCIe concept for tagging > + * address spaces in DMA requests. When system-wide PASID allocation > + * is required by underlying iommu driver (e.g. Intel VT-d), this by the underlying > + * provides an interface for userspace to request pasid alloc/free > + * for its assigned devices. Userspace should check the availability > + * of this API by checking VFIO_IOMMU_TYPE1_INFO_CAP_NESTING through > + * VFIO_IOMMU_GET_INFO. > + * > + * @flags=VFIO_IOMMU_FLAG_ALLOC_PASID, allocate a single PASID within @range. > + * @flags=VFIO_IOMMU_FLAG_FREE_PASID, free the PASIDs within @range. > + * @range is [min, max], which means both @min and @max are inclusive. > + * ALLOC_PASID and FREE_PASID are mutually exclusive. > + * > + * returns: allocated PASID value on success, -errno on failure for > + * ALLOC_PASID; > + * 0 for FREE_PASID operation; > + */ > +struct vfio_iommu_type1_pasid_request { > + __u32 argsz; > +#define VFIO_IOMMU_FLAG_ALLOC_PASID (1 << 0) > +#define VFIO_IOMMU_FLAG_FREE_PASID (1 << 1) > + __u32 flags; > + struct { > + __u32 min; > + __u32 max; > + } range; > +}; > + > +#define VFIO_PASID_REQUEST_MASK (VFIO_IOMMU_FLAG_ALLOC_PASID | \ > + VFIO_IOMMU_FLAG_FREE_PASID) > + > +#define VFIO_IOMMU_PASID_REQUEST _IO(VFIO_TYPE, VFIO_BASE + 18) > + > /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */ > > /* > Otherwise, besides the pieces I would have put directly in the vfio_pasid module patch (EXPORT_SYMBOL_GPL and vfio_mm_ioasid_sid), looks good. Thanks Eric
Hi Eric, > From: Auger Eric <eric.auger@redhat.com> > Sent: Sunday, July 19, 2020 11:39 PM > > Yi, > > On 7/12/20 1:21 PM, Liu Yi L wrote: > > This patch allows user space to request PASID allocation/free, e.g. > > when serving the request from the guest. > > > > PASIDs that are not freed by userspace are automatically freed when > > the IOASID set is destroyed when process exits. > > > > Cc: Kevin Tian <kevin.tian@intel.com> > > CC: Jacob Pan <jacob.jun.pan@linux.intel.com> > > Cc: Alex Williamson <alex.williamson@redhat.com> > > Cc: Eric Auger <eric.auger@redhat.com> > > Cc: Jean-Philippe Brucker <jean-philippe@linaro.org> > > Cc: Joerg Roedel <joro@8bytes.org> > > Cc: Lu Baolu <baolu.lu@linux.intel.com> > > Signed-off-by: Liu Yi L <yi.l.liu@intel.com> > > Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com> > > Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> > > --- > > v4 -> v5: > > *) address comments from Eric Auger. > > *) the comments for the PASID_FREE request is addressed in patch 5/15 of > > this series. > > > > v3 -> v4: > > *) address comments from v3, except the below comment against the range > > of PASID_FREE request. needs more help on it. > > "> +if (req.range.min > req.range.max) > > > > Is it exploitable that a user can spin the kernel for a long time in > > the case of a free by calling this with [0, MAX_UINT] regardless of > > their actual allocations?" > > > > https://lore.kernel.org/linux-iommu/20200702151832.048b44d1@x1.home/ > > > > v1 -> v2: > > *) move the vfio_mm related code to be a seprate module > > *) use a single structure for alloc/free, could support a range of > > PASIDs > > *) fetch vfio_mm at group_attach time instead of at iommu driver open > > time > > --- > > drivers/vfio/Kconfig | 1 + > > drivers/vfio/vfio_iommu_type1.c | 85 > +++++++++++++++++++++++++++++++++++++++++ > > drivers/vfio/vfio_pasid.c | 10 +++++ > > include/linux/vfio.h | 6 +++ > > include/uapi/linux/vfio.h | 37 ++++++++++++++++++ > > 5 files changed, 139 insertions(+) > > > > diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig index > > 3d8a108..95d90c6 100644 > > --- a/drivers/vfio/Kconfig > > +++ b/drivers/vfio/Kconfig > > @@ -2,6 +2,7 @@ > > config VFIO_IOMMU_TYPE1 > > tristate > > depends on VFIO > > + select VFIO_PASID if (X86) > > default n > > > > config VFIO_IOMMU_SPAPR_TCE > > diff --git a/drivers/vfio/vfio_iommu_type1.c > > b/drivers/vfio/vfio_iommu_type1.c index ed80104..55b4065 100644 > > --- a/drivers/vfio/vfio_iommu_type1.c > > +++ b/drivers/vfio/vfio_iommu_type1.c > > @@ -76,6 +76,7 @@ struct vfio_iommu { > > bool dirty_page_tracking; > > bool pinned_page_dirty_scope; > > struct iommu_nesting_info *nesting_info; > > + struct vfio_mm *vmm; > > }; > > > > struct vfio_domain { > > @@ -1937,6 +1938,11 @@ static void vfio_iommu_iova_insert_copy(struct > > vfio_iommu *iommu, > > > > static void vfio_iommu_release_nesting_info(struct vfio_iommu *iommu) > > { > > + if (iommu->vmm) { > > + vfio_mm_put(iommu->vmm); > > + iommu->vmm = NULL; > > + } > > + > > kfree(iommu->nesting_info); > > iommu->nesting_info = NULL; > > } > > @@ -2071,6 +2077,26 @@ static int vfio_iommu_type1_attach_group(void > *iommu_data, > > iommu->nesting_info); > > if (ret) > > goto out_detach; > > + > > + if (iommu->nesting_info->features & > > + IOMMU_NESTING_FEAT_SYSWIDE_PASID) > { > > + struct vfio_mm *vmm; > > + int sid; > > + > > + vmm = vfio_mm_get_from_task(current); > > + if (IS_ERR(vmm)) { > > + ret = PTR_ERR(vmm); > > + goto out_detach; > > + } > > + iommu->vmm = vmm; > > + > > + sid = vfio_mm_ioasid_sid(vmm); > > + ret = iommu_domain_set_attr(domain->domain, > > + DOMAIN_ATTR_IOASID_SID, > > + &sid); > > + if (ret) > > + goto out_detach; > > + } > > } > > > > /* Get aperture info */ > > @@ -2855,6 +2881,63 @@ static int vfio_iommu_type1_dirty_pages(struct > vfio_iommu *iommu, > > return -EINVAL; > > } > > > > +static int vfio_iommu_type1_pasid_alloc(struct vfio_iommu *iommu, > > + unsigned int min, > > + unsigned int max) > > +{ > > + int ret = -EOPNOTSUPP; > > + > > + mutex_lock(&iommu->lock); > > + if (iommu->vmm) > > + ret = vfio_pasid_alloc(iommu->vmm, min, max); > > + mutex_unlock(&iommu->lock); > > + return ret; > > +} > > + > > +static int vfio_iommu_type1_pasid_free(struct vfio_iommu *iommu, > > + unsigned int min, > > + unsigned int max) > > +{ > > + int ret = -EOPNOTSUPP; > > + > > + mutex_lock(&iommu->lock); > > + if (iommu->vmm) { > > + vfio_pasid_free_range(iommu->vmm, min, max); > > + ret = 0; > > + } > > + mutex_unlock(&iommu->lock); > > + return ret; > > +} > > + > > +static int vfio_iommu_type1_pasid_request(struct vfio_iommu *iommu, > > + unsigned long arg) > > +{ > > + struct vfio_iommu_type1_pasid_request req; > > + unsigned long minsz; > > + > > + minsz = offsetofend(struct vfio_iommu_type1_pasid_request, range); > > + > > + if (copy_from_user(&req, (void __user *)arg, minsz)) > > + return -EFAULT; > > + > > + if (req.argsz < minsz || (req.flags & ~VFIO_PASID_REQUEST_MASK)) > > + return -EINVAL; > > + > > + if (req.range.min > req.range.max) > > + return -EINVAL; > > + > > + switch (req.flags & VFIO_PASID_REQUEST_MASK) { > > + case VFIO_IOMMU_FLAG_ALLOC_PASID: > not sure it is worth to introduce both vfio_iommu_type1_pasid_free/alloc > helpers. You could take the lock above, and test iommu->vmm as well above. nice suggestion. thanks. > > + return vfio_iommu_type1_pasid_alloc(iommu, > > + req.range.min, req.range.max); > > + case VFIO_IOMMU_FLAG_FREE_PASID: > > + return vfio_iommu_type1_pasid_free(iommu, > > + req.range.min, req.range.max); > > + default: > > + return -EINVAL; > > + } > > +} > > + > > static long vfio_iommu_type1_ioctl(void *iommu_data, > > unsigned int cmd, unsigned long arg) { @@ - > 2871,6 +2954,8 @@ > > static long vfio_iommu_type1_ioctl(void *iommu_data, > > return vfio_iommu_type1_unmap_dma(iommu, arg); > > case VFIO_IOMMU_DIRTY_PAGES: > > return vfio_iommu_type1_dirty_pages(iommu, arg); > > + case VFIO_IOMMU_PASID_REQUEST: > > + return vfio_iommu_type1_pasid_request(iommu, arg); > > default: > > return -ENOTTY; > > } > > diff --git a/drivers/vfio/vfio_pasid.c b/drivers/vfio/vfio_pasid.c > > index 66e6054e..ebec244 100644 > > --- a/drivers/vfio/vfio_pasid.c > > +++ b/drivers/vfio/vfio_pasid.c > > @@ -61,6 +61,7 @@ void vfio_mm_put(struct vfio_mm *vmm) { > > kref_put_mutex(&vmm->kref, vfio_mm_release, &vfio_mm_lock); } > > +EXPORT_SYMBOL_GPL(vfio_mm_put); > > > > static void vfio_mm_get(struct vfio_mm *vmm) > > { > > @@ -114,6 +115,13 @@ struct vfio_mm *vfio_mm_get_from_task(struct > task_struct *task) > > mmput(mm); > > return vmm; > > } > > +EXPORT_SYMBOL_GPL(vfio_mm_get_from_task); > > + > > +int vfio_mm_ioasid_sid(struct vfio_mm *vmm) > > +{ > > + return vmm->ioasid_sid; > > +} > > +EXPORT_SYMBOL_GPL(vfio_mm_ioasid_sid); > > > > /* > > * Find PASID within @min and @max > > @@ -197,6 +205,7 @@ int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max) > > > > return pasid; > > } > > +EXPORT_SYMBOL_GPL(vfio_pasid_alloc); > > > > void vfio_pasid_free_range(struct vfio_mm *vmm, > > ioasid_t min, ioasid_t max) > > @@ -213,6 +222,7 @@ void vfio_pasid_free_range(struct vfio_mm *vmm, > > vfio_remove_pasid(vmm, vid); > > mutex_unlock(&vmm->pasid_lock); > > } > > +EXPORT_SYMBOL_GPL(vfio_pasid_free_range); > > > > static int __init vfio_pasid_init(void) > > { > > diff --git a/include/linux/vfio.h b/include/linux/vfio.h > > index 31472a9..a111108 100644 > > --- a/include/linux/vfio.h > > +++ b/include/linux/vfio.h > > @@ -101,6 +101,7 @@ struct vfio_mm; > > #if IS_ENABLED(CONFIG_VFIO_PASID) > > extern struct vfio_mm *vfio_mm_get_from_task(struct task_struct *task); > > extern void vfio_mm_put(struct vfio_mm *vmm); > > +int vfio_mm_ioasid_sid(struct vfio_mm *vmm); > I still don't get why it does not take an extern as the other functions > implemented in vfio_pasid.c and used in other modules. what's the > difference? it's a mistake from me. should have "extern" :-) > > extern int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max); > > extern void vfio_pasid_free_range(struct vfio_mm *vmm, > > ioasid_t min, ioasid_t max); > > @@ -114,6 +115,11 @@ static inline void vfio_mm_put(struct vfio_mm *vmm) > > { > > } > > > > +static inline int vfio_mm_ioasid_sid(struct vfio_mm *vmm) > > +{ > > + return -ENOTTY; > > +} > > + > > static inline int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max) > > { > > return -ENOTTY; > > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h > > index 46a78af..96a115f 100644 > > --- a/include/uapi/linux/vfio.h > > +++ b/include/uapi/linux/vfio.h > > @@ -1172,6 +1172,43 @@ struct vfio_iommu_type1_dirty_bitmap_get { > > > > #define VFIO_IOMMU_DIRTY_PAGES _IO(VFIO_TYPE, VFIO_BASE + 17) > > > > +/** > > + * VFIO_IOMMU_PASID_REQUEST - _IOWR(VFIO_TYPE, VFIO_BASE + 18, > > + * struct vfio_iommu_type1_pasid_request) > > + * > > + * PASID (Processor Address Space ID) is a PCIe concept for tagging > > + * address spaces in DMA requests. When system-wide PASID allocation > > + * is required by underlying iommu driver (e.g. Intel VT-d), this > by the underlying got it. > > + * provides an interface for userspace to request pasid alloc/free > > + * for its assigned devices. Userspace should check the availability > > + * of this API by checking VFIO_IOMMU_TYPE1_INFO_CAP_NESTING through > > + * VFIO_IOMMU_GET_INFO. > > + * > > + * @flags=VFIO_IOMMU_FLAG_ALLOC_PASID, allocate a single PASID within > @range. > > + * @flags=VFIO_IOMMU_FLAG_FREE_PASID, free the PASIDs within @range. > > + * @range is [min, max], which means both @min and @max are inclusive. > > + * ALLOC_PASID and FREE_PASID are mutually exclusive. > > + * > > + * returns: allocated PASID value on success, -errno on failure for > > + * ALLOC_PASID; > > + * 0 for FREE_PASID operation; > > + */ > > +struct vfio_iommu_type1_pasid_request { > > + __u32 argsz; > > +#define VFIO_IOMMU_FLAG_ALLOC_PASID (1 << 0) > > +#define VFIO_IOMMU_FLAG_FREE_PASID (1 << 1) > > + __u32 flags; > > + struct { > > + __u32 min; > > + __u32 max; > > + } range; > > +}; > > + > > +#define VFIO_PASID_REQUEST_MASK (VFIO_IOMMU_FLAG_ALLOC_PASID | \ > > + VFIO_IOMMU_FLAG_FREE_PASID) > > + > > +#define VFIO_IOMMU_PASID_REQUEST _IO(VFIO_TYPE, VFIO_BASE + 18) > > + > > /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */ > > > > /* > > > Otherwise, besides the pieces I would have put directly in the > vfio_pasid module patch (EXPORT_SYMBOL_GPL and vfio_mm_ioasid_sid), > looks good. we discussed in another thread:-). Regards, Yi Liu > > Thanks > > Eric
diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig index 3d8a108..95d90c6 100644 --- a/drivers/vfio/Kconfig +++ b/drivers/vfio/Kconfig @@ -2,6 +2,7 @@ config VFIO_IOMMU_TYPE1 tristate depends on VFIO + select VFIO_PASID if (X86) default n config VFIO_IOMMU_SPAPR_TCE diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index ed80104..55b4065 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -76,6 +76,7 @@ struct vfio_iommu { bool dirty_page_tracking; bool pinned_page_dirty_scope; struct iommu_nesting_info *nesting_info; + struct vfio_mm *vmm; }; struct vfio_domain { @@ -1937,6 +1938,11 @@ static void vfio_iommu_iova_insert_copy(struct vfio_iommu *iommu, static void vfio_iommu_release_nesting_info(struct vfio_iommu *iommu) { + if (iommu->vmm) { + vfio_mm_put(iommu->vmm); + iommu->vmm = NULL; + } + kfree(iommu->nesting_info); iommu->nesting_info = NULL; } @@ -2071,6 +2077,26 @@ static int vfio_iommu_type1_attach_group(void *iommu_data, iommu->nesting_info); if (ret) goto out_detach; + + if (iommu->nesting_info->features & + IOMMU_NESTING_FEAT_SYSWIDE_PASID) { + struct vfio_mm *vmm; + int sid; + + vmm = vfio_mm_get_from_task(current); + if (IS_ERR(vmm)) { + ret = PTR_ERR(vmm); + goto out_detach; + } + iommu->vmm = vmm; + + sid = vfio_mm_ioasid_sid(vmm); + ret = iommu_domain_set_attr(domain->domain, + DOMAIN_ATTR_IOASID_SID, + &sid); + if (ret) + goto out_detach; + } } /* Get aperture info */ @@ -2855,6 +2881,63 @@ static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu, return -EINVAL; } +static int vfio_iommu_type1_pasid_alloc(struct vfio_iommu *iommu, + unsigned int min, + unsigned int max) +{ + int ret = -EOPNOTSUPP; + + mutex_lock(&iommu->lock); + if (iommu->vmm) + ret = vfio_pasid_alloc(iommu->vmm, min, max); + mutex_unlock(&iommu->lock); + return ret; +} + +static int vfio_iommu_type1_pasid_free(struct vfio_iommu *iommu, + unsigned int min, + unsigned int max) +{ + int ret = -EOPNOTSUPP; + + mutex_lock(&iommu->lock); + if (iommu->vmm) { + vfio_pasid_free_range(iommu->vmm, min, max); + ret = 0; + } + mutex_unlock(&iommu->lock); + return ret; +} + +static int vfio_iommu_type1_pasid_request(struct vfio_iommu *iommu, + unsigned long arg) +{ + struct vfio_iommu_type1_pasid_request req; + unsigned long minsz; + + minsz = offsetofend(struct vfio_iommu_type1_pasid_request, range); + + if (copy_from_user(&req, (void __user *)arg, minsz)) + return -EFAULT; + + if (req.argsz < minsz || (req.flags & ~VFIO_PASID_REQUEST_MASK)) + return -EINVAL; + + if (req.range.min > req.range.max) + return -EINVAL; + + switch (req.flags & VFIO_PASID_REQUEST_MASK) { + case VFIO_IOMMU_FLAG_ALLOC_PASID: + return vfio_iommu_type1_pasid_alloc(iommu, + req.range.min, req.range.max); + case VFIO_IOMMU_FLAG_FREE_PASID: + return vfio_iommu_type1_pasid_free(iommu, + req.range.min, req.range.max); + default: + return -EINVAL; + } +} + static long vfio_iommu_type1_ioctl(void *iommu_data, unsigned int cmd, unsigned long arg) { @@ -2871,6 +2954,8 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, return vfio_iommu_type1_unmap_dma(iommu, arg); case VFIO_IOMMU_DIRTY_PAGES: return vfio_iommu_type1_dirty_pages(iommu, arg); + case VFIO_IOMMU_PASID_REQUEST: + return vfio_iommu_type1_pasid_request(iommu, arg); default: return -ENOTTY; } diff --git a/drivers/vfio/vfio_pasid.c b/drivers/vfio/vfio_pasid.c index 66e6054e..ebec244 100644 --- a/drivers/vfio/vfio_pasid.c +++ b/drivers/vfio/vfio_pasid.c @@ -61,6 +61,7 @@ void vfio_mm_put(struct vfio_mm *vmm) { kref_put_mutex(&vmm->kref, vfio_mm_release, &vfio_mm_lock); } +EXPORT_SYMBOL_GPL(vfio_mm_put); static void vfio_mm_get(struct vfio_mm *vmm) { @@ -114,6 +115,13 @@ struct vfio_mm *vfio_mm_get_from_task(struct task_struct *task) mmput(mm); return vmm; } +EXPORT_SYMBOL_GPL(vfio_mm_get_from_task); + +int vfio_mm_ioasid_sid(struct vfio_mm *vmm) +{ + return vmm->ioasid_sid; +} +EXPORT_SYMBOL_GPL(vfio_mm_ioasid_sid); /* * Find PASID within @min and @max @@ -197,6 +205,7 @@ int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max) return pasid; } +EXPORT_SYMBOL_GPL(vfio_pasid_alloc); void vfio_pasid_free_range(struct vfio_mm *vmm, ioasid_t min, ioasid_t max) @@ -213,6 +222,7 @@ void vfio_pasid_free_range(struct vfio_mm *vmm, vfio_remove_pasid(vmm, vid); mutex_unlock(&vmm->pasid_lock); } +EXPORT_SYMBOL_GPL(vfio_pasid_free_range); static int __init vfio_pasid_init(void) { diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 31472a9..a111108 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -101,6 +101,7 @@ struct vfio_mm; #if IS_ENABLED(CONFIG_VFIO_PASID) extern struct vfio_mm *vfio_mm_get_from_task(struct task_struct *task); extern void vfio_mm_put(struct vfio_mm *vmm); +int vfio_mm_ioasid_sid(struct vfio_mm *vmm); extern int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max); extern void vfio_pasid_free_range(struct vfio_mm *vmm, ioasid_t min, ioasid_t max); @@ -114,6 +115,11 @@ static inline void vfio_mm_put(struct vfio_mm *vmm) { } +static inline int vfio_mm_ioasid_sid(struct vfio_mm *vmm) +{ + return -ENOTTY; +} + static inline int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max) { return -ENOTTY; diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 46a78af..96a115f 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -1172,6 +1172,43 @@ struct vfio_iommu_type1_dirty_bitmap_get { #define VFIO_IOMMU_DIRTY_PAGES _IO(VFIO_TYPE, VFIO_BASE + 17) +/** + * VFIO_IOMMU_PASID_REQUEST - _IOWR(VFIO_TYPE, VFIO_BASE + 18, + * struct vfio_iommu_type1_pasid_request) + * + * PASID (Processor Address Space ID) is a PCIe concept for tagging + * address spaces in DMA requests. When system-wide PASID allocation + * is required by underlying iommu driver (e.g. Intel VT-d), this + * provides an interface for userspace to request pasid alloc/free + * for its assigned devices. Userspace should check the availability + * of this API by checking VFIO_IOMMU_TYPE1_INFO_CAP_NESTING through + * VFIO_IOMMU_GET_INFO. + * + * @flags=VFIO_IOMMU_FLAG_ALLOC_PASID, allocate a single PASID within @range. + * @flags=VFIO_IOMMU_FLAG_FREE_PASID, free the PASIDs within @range. + * @range is [min, max], which means both @min and @max are inclusive. + * ALLOC_PASID and FREE_PASID are mutually exclusive. + * + * returns: allocated PASID value on success, -errno on failure for + * ALLOC_PASID; + * 0 for FREE_PASID operation; + */ +struct vfio_iommu_type1_pasid_request { + __u32 argsz; +#define VFIO_IOMMU_FLAG_ALLOC_PASID (1 << 0) +#define VFIO_IOMMU_FLAG_FREE_PASID (1 << 1) + __u32 flags; + struct { + __u32 min; + __u32 max; + } range; +}; + +#define VFIO_PASID_REQUEST_MASK (VFIO_IOMMU_FLAG_ALLOC_PASID | \ + VFIO_IOMMU_FLAG_FREE_PASID) + +#define VFIO_IOMMU_PASID_REQUEST _IO(VFIO_TYPE, VFIO_BASE + 18) + /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */ /*