[PATCH v1 06/14] vfio: Add vma to pfn callback
From: Alex Williamson <hidden>
Date: 2021-03-08 21:49:20
Also in:
lkml
Subsystem:
the rest, vfio driver · Maintainers:
Linus Torvalds, Alex Williamson
Add a new vfio_device_ops callback to allow the bus driver to translate a vma mapping of a vfio device fd to a pfn. Plumb through vfio-core. Implemented for vfio-pci. Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Alex Williamson <redacted> --- drivers/vfio/pci/vfio_pci.c | 1 + drivers/vfio/vfio.c | 16 ++++++++++++++++ include/linux/vfio.h | 3 +++ 3 files changed, 20 insertions(+)
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 415b5109da9b..585895970e9c 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c@@ -1756,6 +1756,7 @@ static const struct vfio_device_ops vfio_pci_ops = { .mmap = vfio_pci_mmap, .request = vfio_pci_request, .match = vfio_pci_match, + .vma_to_pfn = vfio_pci_bar_vma_to_pfn, }; static int vfio_pci_reflck_attach(struct vfio_pci_device *vdev);
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 3a3e85a0dc3e..c47895539a1a 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c@@ -944,6 +944,22 @@ struct vfio_device *vfio_device_get_from_vma(struct vm_area_struct *vma) } EXPORT_SYMBOL_GPL(vfio_device_get_from_vma); +int vfio_vma_to_pfn(struct vm_area_struct *vma, unsigned long *pfn) +{ + struct vfio_device *device; + + if (!vma->vm_file || vma->vm_file->f_op != &vfio_device_fops) + return -EINVAL; + + device = vma->vm_file->private_data; + + if (unlikely(!device->ops->vma_to_pfn)) + return -EINVAL; + + return device->ops->vma_to_pfn(vma, pfn); +} +EXPORT_SYMBOL_GPL(vfio_vma_to_pfn); + static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group, char *buf) {
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 660b8adf90a6..dbd90d0ba713 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h@@ -29,6 +29,7 @@ * @match: Optional device name match callback (return: 0 for no-match, >0 for * match, -errno for abort (ex. match with insufficient or incorrect * additional args) + * @vma_to_pfn: Optional pfn from vma lookup against vma mapping device fd */ struct vfio_device_ops { char *name;
@@ -43,6 +44,7 @@ struct vfio_device_ops { int (*mmap)(void *device_data, struct vm_area_struct *vma); void (*request)(void *device_data, unsigned int count); int (*match)(void *device_data, char *buf); + int (*vma_to_pfn)(struct vm_area_struct *vma, unsigned long *pfn); }; extern struct iommu_group *vfio_iommu_group_get(struct device *dev);
@@ -59,6 +61,7 @@ extern void *vfio_device_data(struct vfio_device *device); extern void vfio_device_unmap_mapping_range(struct vfio_device *device, loff_t start, loff_t len); extern struct vfio_device *vfio_device_get_from_vma(struct vm_area_struct *vma); +extern int vfio_vma_to_pfn(struct vm_area_struct *vma, unsigned long *pfn); /* events for the backend driver notify callback */ enum vfio_iommu_notify_type {