Commit ba6090ff authored by Matthew Rosato's avatar Matthew Rosato Committed by Christian Borntraeger
Browse files

vfio-pci/zdev: different maxstbl for interpreted devices 



When doing load/store interpretation, the maximum store block length is
determined by the underlying firmware, not the host kernel API.  Reflect
that in the associated Query PCI Function Group clp capability and let
userspace decide which is appropriate to present to the guest.

Reviewed-by: default avatarPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: default avatarMatthew Rosato <mjrosato@linux.ibm.com>
Acked-by: default avatarAlex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20220606203325.110625-20-mjrosato@linux.ibm.com


Signed-off-by: default avatarChristian Borntraeger <borntraeger@linux.ibm.com>
parent faf3bfcb

drivers/vfio/pci/vfio_pci_zdev.c

+4 −2
Original line number Diff line number Diff line
@@ -45,14 +45,16 @@ static int zpci_group_cap(struct zpci_dev *zdev, struct vfio_info_cap *caps) 
{

	struct vfio_device_info_cap_zpci_group cap = {

		.header.id = VFIO_DEVICE_INFO_CAP_ZPCI_GROUP,

		.header.version = 1,

		.header.version = 2,

		.dasm = zdev->dma_mask,

		.msi_addr = zdev->msi_addr,

		.flags = VFIO_DEVICE_INFO_ZPCI_FLAG_REFRESH,

		.mui = zdev->fmb_update,

		.noi = zdev->max_msi,

		.maxstbl = ZPCI_MAX_WRITE_SIZE,

		.version = zdev->version

		.version = zdev->version,

		.reserved = 0,

		.imaxstbl = zdev->maxstbl

	};



	return vfio_info_add_capability(caps, &cap.header, sizeof(cap));

include/uapi/linux/vfio_zdev.h

+4 −0
Original line number Diff line number Diff line
@@ -50,6 +50,10 @@ struct vfio_device_info_cap_zpci_group { 
	__u16 noi;		/* Maximum number of MSIs */

	__u16 maxstbl;		/* Maximum Store Block Length */

	__u8 version;		/* Supported PCI Version */

	/* End of version 1 */

	__u8 reserved;

	__u16 imaxstbl;		/* Maximum Interpreted Store Block Length */

	/* End of version 2 */

};



/**