This patch adds the VFIO_IOMMU_SET_MSI_BINDING ioctl which aim to (un)register the guest MSI binding to the host. This latter then can use those stage 1 bindings to build a nested stage binding targeting the physical MSIs.
Signed-off-by: Eric Auger <eric.au...@redhat.com> --- v11 -> v12: - Share VFIO_BASE + 20 with VFIO_IOMMU_SPAPR_TCE_REMOVE - rework returned values v10 -> v11: - renamed ustruct into msi_binding - return 0 on unbind v8 -> v9: - merge VFIO_IOMMU_BIND_MSI/VFIO_IOMMU_UNBIND_MSI into a single VFIO_IOMMU_SET_MSI_BINDING ioctl - ioctl id changed v6 -> v7: - removed the dev arg v3 -> v4: - add UNBIND - unwind on BIND error 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 | 62 +++++++++++++++++++++++++++++++++ include/uapi/linux/vfio.h | 20 +++++++++++ 2 files changed, 82 insertions(+) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index b4057ce809b0..0e6af4fe8c3d 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -2655,6 +2655,41 @@ static int vfio_cache_inv_fn(struct device *dev, void *data) return iommu_uapi_cache_invalidate(dc->domain, dev, (void __user *)arg); } +static int +vfio_bind_msi(struct vfio_iommu *iommu, + dma_addr_t giova, phys_addr_t gpa, size_t size) +{ + struct vfio_domain *d; + int ret = 0; + + mutex_lock(&iommu->lock); + + list_for_each_entry(d, &iommu->domain_list, next) { + ret = iommu_bind_guest_msi(d->domain, giova, gpa, size); + if (ret) + goto unwind; + } + goto unlock; +unwind: + list_for_each_entry_continue_reverse(d, &iommu->domain_list, next) { + iommu_unbind_guest_msi(d->domain, giova); + } +unlock: + mutex_unlock(&iommu->lock); + return ret; +} + +static void +vfio_unbind_msi(struct vfio_iommu *iommu, dma_addr_t giova) +{ + struct vfio_domain *d; + + mutex_lock(&iommu->lock); + list_for_each_entry(d, &iommu->domain_list, next) + iommu_unbind_guest_msi(d->domain, giova); + mutex_unlock(&iommu->lock); +} + static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu, struct vfio_info_cap *caps) { @@ -2859,6 +2894,31 @@ static int vfio_iommu_type1_cache_invalidate(struct vfio_iommu *iommu, return ret; } +static int vfio_iommu_type1_set_msi_binding(struct vfio_iommu *iommu, + unsigned long arg) +{ + struct vfio_iommu_type1_set_msi_binding msi_binding; + unsigned long minsz; + + minsz = offsetofend(struct vfio_iommu_type1_set_msi_binding, + size); + + if (copy_from_user(&msi_binding, (void __user *)arg, minsz)) + return -EFAULT; + + if (msi_binding.argsz < minsz) + return -EINVAL; + + if (msi_binding.flags == VFIO_IOMMU_UNBIND_MSI) { + vfio_unbind_msi(iommu, msi_binding.iova); + return 0; + } else if (msi_binding.flags == VFIO_IOMMU_BIND_MSI) { + return vfio_bind_msi(iommu, msi_binding.iova, + msi_binding.gpa, msi_binding.size); + } + return -EINVAL; +} + static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu, unsigned long arg) { @@ -2983,6 +3043,8 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, return vfio_iommu_type1_set_pasid_table(iommu, arg); case VFIO_IOMMU_CACHE_INVALIDATE: return vfio_iommu_type1_cache_invalidate(iommu, arg); + case VFIO_IOMMU_SET_MSI_BINDING: + return vfio_iommu_type1_set_msi_binding(iommu, arg); default: return -ENOTTY; } diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index ee6747ff8006..4c82e8f21618 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -1213,6 +1213,26 @@ struct vfio_iommu_type1_cache_invalidate { }; #define VFIO_IOMMU_CACHE_INVALIDATE _IO(VFIO_TYPE, VFIO_BASE + 19) +/** + * VFIO_IOMMU_SET_MSI_BINDING - _IOWR(VFIO_TYPE, VFIO_BASE + 20, + * struct vfio_iommu_type1_set_msi_binding) + * + * Pass a stage 1 MSI doorbell mapping to the host so that this + * latter can build a nested stage2 mapping. Or conversely tear + * down a previously bound stage 1 MSI binding. + */ +struct vfio_iommu_type1_set_msi_binding { + __u32 argsz; + __u32 flags; +#define VFIO_IOMMU_BIND_MSI (1 << 0) +#define VFIO_IOMMU_UNBIND_MSI (1 << 1) + __u64 iova; /* MSI guest IOVA */ + /* Fields below are used on BIND */ + __u64 gpa; /* MSI guest physical address */ + __u64 size; /* size of stage1 mapping (bytes) */ +}; +#define VFIO_IOMMU_SET_MSI_BINDING _IO(VFIO_TYPE, VFIO_BASE + 20) + /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */ /* -- 2.26.2