Commit b3c0a866 authored by Kirti Wankhede's avatar Kirti Wankhede Committed by Alex Williamson
Browse files

vfio: Introduce common function to add capabilities 



Vendor driver using mediated device framework should use
vfio_info_add_capability() to add capabilities.
Introduced this function to reduce code duplication in vendor drivers.

vfio_info_cap_shift() manipulated a data buffer to add an offset to each
element in a chain. This data buffer is documented in a uapi header.
Changing vfio_info_cap_shift symbol to be available to all drivers.

Signed-off-by: default avatarKirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: default avatarNeo Jia <cjia@nvidia.com>
Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent c086de81

drivers/vfio/vfio.c

+59 −1
Original line number Diff line number Diff line
@@ -1797,8 +1797,66 @@ void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset) 
	for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next - offset)

		tmp->next += offset;

}

EXPORT_SYMBOL_GPL(vfio_info_cap_shift);

EXPORT_SYMBOL(vfio_info_cap_shift);



static int sparse_mmap_cap(struct vfio_info_cap *caps, void *cap_type)

{

	struct vfio_info_cap_header *header;

	struct vfio_region_info_cap_sparse_mmap *sparse_cap, *sparse = cap_type;

	size_t size;



	size = sizeof(*sparse) + sparse->nr_areas *  sizeof(*sparse->areas);

	header = vfio_info_cap_add(caps, size,

				   VFIO_REGION_INFO_CAP_SPARSE_MMAP, 1);

	if (IS_ERR(header))

		return PTR_ERR(header);



	sparse_cap = container_of(header,

			struct vfio_region_info_cap_sparse_mmap, header);

	sparse_cap->nr_areas = sparse->nr_areas;

	memcpy(sparse_cap->areas, sparse->areas,

	       sparse->nr_areas * sizeof(*sparse->areas));

	return 0;

}



static int region_type_cap(struct vfio_info_cap *caps, void *cap_type)

{

	struct vfio_info_cap_header *header;

	struct vfio_region_info_cap_type *type_cap, *cap = cap_type;



	header = vfio_info_cap_add(caps, sizeof(*cap),

				   VFIO_REGION_INFO_CAP_TYPE, 1);

	if (IS_ERR(header))

		return PTR_ERR(header);



	type_cap = container_of(header, struct vfio_region_info_cap_type,

				header);

	type_cap->type = cap->type;

	type_cap->subtype = cap->subtype;

	return 0;

}



int vfio_info_add_capability(struct vfio_info_cap *caps, int cap_type_id,

			     void *cap_type)

{

	int ret = -EINVAL;



	if (!cap_type)

		return 0;



	switch (cap_type_id) {

	case VFIO_REGION_INFO_CAP_SPARSE_MMAP:

		ret = sparse_mmap_cap(caps, cap_type);

		break;



	case VFIO_REGION_INFO_CAP_TYPE:

		ret = region_type_cap(caps, cap_type);

		break;

	}



	return ret;

}

EXPORT_SYMBOL(vfio_info_add_capability);



/*

 * Pin a set of guest PFNs and return their associated host PFNs for local

include/linux/vfio.h

+3 −0
Original line number Diff line number Diff line
@@ -126,6 +126,9 @@ extern struct vfio_info_cap_header *vfio_info_cap_add( 
		struct vfio_info_cap *caps, size_t size, u16 id, u16 version);

extern void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);



extern int vfio_info_add_capability(struct vfio_info_cap *caps,

				    int cap_type_id, void *cap_type);



struct pci_dev;

#ifdef CONFIG_EEH

extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);

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