From 13e522f644e2b15fa857028a33e6a3b75e45158d Mon Sep 17 00:00:00 2001
From: Joao Martins <joao.m.martins@oracle.com>
Date: Fri, 19 Jul 2024 13:04:49 +0100
Subject: [PATCH] vfio/pci: Extract mdev check into an helper
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
In preparation to skip initialization of the HostIOMMUDevice for mdev,
extract the checks that validate if a device is an mdev into helpers.
A vfio_device_is_mdev() is created, and subsystems consult VFIODevice::mdev
to check if it's mdev or not.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
hw/vfio/helpers.c | 14 ++++++++++++++
hw/vfio/pci.c | 12 +++---------
include/hw/vfio/vfio-common.h | 2 ++
3 files changed, 19 insertions(+), 9 deletions(-)
diff --git a/hw/vfio/helpers.c b/hw/vfio/helpers.c
index b14edd46ed..7e23e9080c 100644
--- a/hw/vfio/helpers.c
+++ b/hw/vfio/helpers.c
@@ -675,3 +675,17 @@ int vfio_device_get_aw_bits(VFIODevice *vdev)
return HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX;
}
+
+bool vfio_device_is_mdev(VFIODevice *vbasedev)
+{
+ g_autofree char *subsys = NULL;
+ g_autofree char *tmp = NULL;
+
+ if (!vbasedev->sysfsdev) {
+ return false;
+ }
+
+ tmp = g_strdup_printf("%s/subsystem", vbasedev->sysfsdev);
+ subsys = realpath(tmp, NULL);
+ return subsys && (strcmp(subsys, "/sys/bus/mdev") == 0);
+}
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index e03d9f3ba5..b34e91468a 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2963,12 +2963,9 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
ERRP_GUARD();
VFIOPCIDevice *vdev = VFIO_PCI(pdev);
VFIODevice *vbasedev = &vdev->vbasedev;
- char *subsys;
int i, ret;
- bool is_mdev;
char uuid[UUID_STR_LEN];
g_autofree char *name = NULL;
- g_autofree char *tmp = NULL;
if (vbasedev->fd < 0 && !vbasedev->sysfsdev) {
if (!(~vdev->host.domain || ~vdev->host.bus ||
@@ -2997,14 +2994,11 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
* stays in sync with the active working set of the guest driver. Prevent
* the x-balloon-allowed option unless this is minimally an mdev device.
*/
- tmp = g_strdup_printf("%s/subsystem", vbasedev->sysfsdev);
- subsys = realpath(tmp, NULL);
- is_mdev = subsys && (strcmp(subsys, "/sys/bus/mdev") == 0);
- free(subsys);
+ vbasedev->mdev = vfio_device_is_mdev(vbasedev);
- trace_vfio_mdev(vbasedev->name, is_mdev);
+ trace_vfio_mdev(vbasedev->name, vbasedev->mdev);
- if (vbasedev->ram_block_discard_allowed && !is_mdev) {
+ if (vbasedev->ram_block_discard_allowed && !vbasedev->mdev) {
error_setg(errp, "x-balloon-allowed only potentially compatible "
"with mdev devices");
goto error;
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index e8ddf92bb1..98acae8c1c 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -116,6 +116,7 @@ typedef struct VFIODevice {
DeviceState *dev;
int fd;
int type;
+ bool mdev;
bool reset_works;
bool needs_reset;
bool no_mmap;
@@ -231,6 +232,7 @@ void vfio_region_exit(VFIORegion *region);
void vfio_region_finalize(VFIORegion *region);
void vfio_reset_handler(void *opaque);
struct vfio_device_info *vfio_get_device_info(int fd);
+bool vfio_device_is_mdev(VFIODevice *vbasedev);
bool vfio_attach_device(char *name, VFIODevice *vbasedev,
AddressSpace *as, Error **errp);
void vfio_detach_device(VFIODevice *vbasedev);