[PATCH 9/9] vfio/pci: export igd support into vendor vfio_pci driver

From: Max Gurtovoy
Date: Tue Mar 09 2021 - 03:37:00 EST


Create a new driver igd_vfio_pci.ko that will be responsible for
providing special extensions for INTEL Graphics card (GVT-d).

Also preserve backward compatibility with vfio_pci.ko vendor specific
extensions.

Signed-off-by: Max Gurtovoy <mgurtovoy@xxxxxxxxxx>
---
drivers/vfio/pci/Kconfig | 5 +-
drivers/vfio/pci/Makefile | 4 +-
.../pci/{vfio_pci_igd.c => igd_vfio_pci.c} | 147 +++++++++++++++++-
drivers/vfio/pci/igd_vfio_pci.h | 24 +++
drivers/vfio/pci/vfio_pci.c | 4 +
drivers/vfio/pci/vfio_pci_core.c | 15 --
drivers/vfio/pci/vfio_pci_core.h | 9 --
7 files changed, 176 insertions(+), 32 deletions(-)
rename drivers/vfio/pci/{vfio_pci_igd.c => igd_vfio_pci.c} (62%)
create mode 100644 drivers/vfio/pci/igd_vfio_pci.h

diff --git a/drivers/vfio/pci/Kconfig b/drivers/vfio/pci/Kconfig
index 88c89863a205..09d85ba3e5b2 100644
--- a/drivers/vfio/pci/Kconfig
+++ b/drivers/vfio/pci/Kconfig
@@ -37,17 +37,14 @@ config VFIO_PCI_INTX
def_bool y if !S390

config VFIO_PCI_IGD
- bool "VFIO PCI extensions for Intel graphics (GVT-d)"
+ tristate "VFIO PCI extensions for Intel graphics (GVT-d)"
depends on VFIO_PCI_CORE && X86
- default y
help
Support for Intel IGD specific extensions to enable direct
assignment to virtual machines. This includes exposing an IGD
specific firmware table and read-only copies of the host bridge
and LPC bridge config space.

- To enable Intel IGD assignment through vfio-pci, say Y.
-
config VFIO_PCI_NVLINK2GPU
tristate "VFIO support for NVIDIA NVLINK2 GPUs"
depends on VFIO_PCI_CORE && PPC_POWERNV
diff --git a/drivers/vfio/pci/Makefile b/drivers/vfio/pci/Makefile
index 86fb62e271fc..298b2fb3f075 100644
--- a/drivers/vfio/pci/Makefile
+++ b/drivers/vfio/pci/Makefile
@@ -4,9 +4,9 @@ obj-$(CONFIG_VFIO_PCI_CORE) += vfio-pci-core.o
obj-$(CONFIG_VFIO_PCI) += vfio-pci.o
obj-$(CONFIG_VFIO_PCI_NPU2) += npu2-vfio-pci.o
obj-$(CONFIG_VFIO_PCI_NVLINK2GPU) += nvlink2gpu-vfio-pci.o
+obj-$(CONFIG_VFIO_PCI_IGD) += igd-vfio-pci.o

vfio-pci-core-y := vfio_pci_core.o vfio_pci_intrs.o vfio_pci_rdwr.o vfio_pci_config.o
-vfio-pci-core-$(CONFIG_VFIO_PCI_IGD) += vfio_pci_igd.o
vfio-pci-core-$(CONFIG_S390) += vfio_pci_zdev.o

vfio-pci-y := vfio_pci.o
@@ -14,3 +14,5 @@ vfio-pci-y := vfio_pci.o
npu2-vfio-pci-y := npu2_vfio_pci.o

nvlink2gpu-vfio-pci-y := nvlink2gpu_vfio_pci.o
+
+igd-vfio-pci-y := igd_vfio_pci.o
diff --git a/drivers/vfio/pci/vfio_pci_igd.c b/drivers/vfio/pci/igd_vfio_pci.c
similarity index 62%
rename from drivers/vfio/pci/vfio_pci_igd.c
rename to drivers/vfio/pci/igd_vfio_pci.c
index 2388c9722ed8..bbbc432bca82 100644
--- a/drivers/vfio/pci/vfio_pci_igd.c
+++ b/drivers/vfio/pci/igd_vfio_pci.c
@@ -10,19 +10,32 @@
* address is also virtualized to prevent user modification.
*/

+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
#include <linux/io.h>
#include <linux/pci.h>
+#include <linux/list.h>
#include <linux/uaccess.h>
#include <linux/vfio.h>

#include "vfio_pci_core.h"
+#include "igd_vfio_pci.h"

#define OPREGION_SIGNATURE "IntelGraphicsMem"
#define OPREGION_SIZE (8 * 1024)
#define OPREGION_PCI_ADDR 0xfc

-static size_t vfio_pci_igd_rw(struct vfio_pci_core_device *vdev, char __user *buf,
- size_t count, loff_t *ppos, bool iswrite)
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@xxxxxxxxxx>"
+#define DRIVER_DESC "IGD VFIO PCI - User Level meta-driver for Intel Graphics Processing Unit"
+
+struct igd_vfio_pci_device {
+ struct vfio_pci_core_device vdev;
+};
+
+static size_t vfio_pci_igd_rw(struct vfio_pci_core_device *vdev,
+ char __user *buf, size_t count, loff_t *ppos, bool iswrite)
{
unsigned int i = VFIO_PCI_OFFSET_TO_INDEX(*ppos) - VFIO_PCI_NUM_REGIONS;
void *base = vdev->region[i].data;
@@ -261,7 +274,7 @@ static int vfio_pci_igd_cfg_init(struct vfio_pci_core_device *vdev)
return 0;
}

-int vfio_pci_igd_init(struct vfio_pci_core_device *vdev)
+static int vfio_pci_igd_init(struct vfio_pci_core_device *vdev)
{
int ret;

@@ -275,3 +288,131 @@ int vfio_pci_igd_init(struct vfio_pci_core_device *vdev)

return 0;
}
+
+static void igd_vfio_pci_release(void *device_data)
+{
+ struct vfio_pci_core_device *vdev = device_data;
+
+ mutex_lock(&vdev->reflck->lock);
+ if (!(--vdev->refcnt)) {
+ vfio_pci_vf_token_user_add(vdev, -1);
+ vfio_pci_core_spapr_eeh_release(vdev);
+ vfio_pci_core_disable(vdev);
+ }
+ mutex_unlock(&vdev->reflck->lock);
+
+ module_put(THIS_MODULE);
+}
+
+static int igd_vfio_pci_open(void *device_data)
+{
+ struct vfio_pci_core_device *vdev = device_data;
+ int ret = 0;
+
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ mutex_lock(&vdev->reflck->lock);
+
+ if (!vdev->refcnt) {
+ ret = vfio_pci_core_enable(vdev);
+ if (ret)
+ goto error;
+
+ ret = vfio_pci_igd_init(vdev);
+ if (ret && ret != -ENODEV) {
+ pci_warn(vdev->pdev, "Failed to setup Intel IGD regions\n");
+ vfio_pci_core_disable(vdev);
+ goto error;
+ }
+ ret = 0;
+ vfio_pci_probe_mmaps(vdev);
+ vfio_pci_core_spapr_eeh_open(vdev);
+ vfio_pci_vf_token_user_add(vdev, 1);
+ }
+ vdev->refcnt++;
+error:
+ mutex_unlock(&vdev->reflck->lock);
+ if (ret)
+ module_put(THIS_MODULE);
+ return ret;
+}
+
+static const struct vfio_device_ops igd_vfio_pci_ops = {
+ .name = "igd-vfio-pci",
+ .open = igd_vfio_pci_open,
+ .release = igd_vfio_pci_release,
+ .ioctl = vfio_pci_core_ioctl,
+ .read = vfio_pci_core_read,
+ .write = vfio_pci_core_write,
+ .mmap = vfio_pci_core_mmap,
+ .request = vfio_pci_core_request,
+ .match = vfio_pci_core_match,
+};
+
+static int igd_vfio_pci_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ struct igd_vfio_pci_device *igvdev;
+ int ret;
+
+ igvdev = kzalloc(sizeof(*igvdev), GFP_KERNEL);
+ if (!igvdev)
+ return -ENOMEM;
+
+ ret = vfio_pci_core_register_device(&igvdev->vdev, pdev,
+ &igd_vfio_pci_ops);
+ if (ret)
+ goto out_free;
+
+ return 0;
+
+out_free:
+ kfree(igvdev);
+ return ret;
+}
+
+static void igd_vfio_pci_remove(struct pci_dev *pdev)
+{
+ struct vfio_device *vdev = dev_get_drvdata(&pdev->dev);
+ struct vfio_pci_core_device *core_vpdev = vfio_device_data(vdev);
+ struct igd_vfio_pci_device *igvdev;
+
+ igvdev = container_of(core_vpdev, struct igd_vfio_pci_device, vdev);
+
+ vfio_pci_core_unregister_device(core_vpdev);
+ kfree(igvdev);
+}
+
+static const struct pci_device_id igd_vfio_pci_table[] = {
+ { PCI_VENDOR_ID_INTEL, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_DISPLAY_VGA << 8, 0xff0000, 0 },
+ { 0, }
+};
+
+static struct pci_driver igd_vfio_pci_driver = {
+ .name = "igd-vfio-pci",
+ .id_table = igd_vfio_pci_table,
+ .probe = igd_vfio_pci_probe,
+ .remove = igd_vfio_pci_remove,
+#ifdef CONFIG_PCI_IOV
+ .sriov_configure = vfio_pci_core_sriov_configure,
+#endif
+ .err_handler = &vfio_pci_core_err_handlers,
+};
+
+#ifdef CONFIG_VFIO_PCI_DRIVER_COMPAT
+struct pci_driver *get_igd_vfio_pci_driver(struct pci_dev *pdev)
+{
+ if (pci_match_id(igd_vfio_pci_driver.id_table, pdev))
+ return &igd_vfio_pci_driver;
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(get_igd_vfio_pci_driver);
+#endif
+
+module_pci_driver(igd_vfio_pci_driver);
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
diff --git a/drivers/vfio/pci/igd_vfio_pci.h b/drivers/vfio/pci/igd_vfio_pci.h
new file mode 100644
index 000000000000..859aeca354cb
--- /dev/null
+++ b/drivers/vfio/pci/igd_vfio_pci.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2020, Mellanox Technologies, Ltd. All rights reserved.
+ * Author: Max Gurtovoy <mgurtovoy@xxxxxxxxxx>
+ */
+
+#ifndef IGD_VFIO_PCI_H
+#define IGD_VFIO_PCI_H
+
+#include <linux/pci.h>
+#include <linux/module.h>
+
+#ifdef CONFIG_VFIO_PCI_DRIVER_COMPAT
+#if defined(CONFIG_VFIO_PCI_IGD) || defined(CONFIG_VFIO_PCI_IGD_MODULE)
+struct pci_driver *get_igd_vfio_pci_driver(struct pci_dev *pdev);
+#else
+struct pci_driver *get_igd_vfio_pci_driver(struct pci_dev *pdev)
+{
+ return NULL;
+}
+#endif
+#endif
+
+#endif /* IGD_VFIO_PCI_H */
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 8e81ea039f31..1c2f6d55a243 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -30,6 +30,7 @@
#ifdef CONFIG_VFIO_PCI_DRIVER_COMPAT
#include "npu2_vfio_pci.h"
#include "nvlink2gpu_vfio_pci.h"
+#include "igd_vfio_pci.h"
#endif

#define DRIVER_VERSION "0.2"
@@ -170,6 +171,9 @@ static struct pci_driver *vfio_pci_get_compat_driver(struct pci_dev *pdev)
default:
return NULL;
}
+ case PCI_VENDOR_ID_INTEL:
+ if (pdev->class == PCI_CLASS_DISPLAY_VGA << 8)
+ return get_igd_vfio_pci_driver(pdev);
}

return NULL;
diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index f9b39abe54cb..59c9d0d56a0b 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -343,22 +343,7 @@ int vfio_pci_core_enable(struct vfio_pci_core_device *vdev)
if (!vfio_vga_disabled() && vfio_pci_is_vga(pdev))
vdev->has_vga = true;

-
- if (vfio_pci_is_vga(pdev) &&
- pdev->vendor == PCI_VENDOR_ID_INTEL &&
- IS_ENABLED(CONFIG_VFIO_PCI_IGD)) {
- ret = vfio_pci_igd_init(vdev);
- if (ret && ret != -ENODEV) {
- pci_warn(pdev, "Failed to setup Intel IGD regions\n");
- goto disable_exit;
- }
- }
-
return 0;
-
-disable_exit:
- vfio_pci_disable(vdev);
- return ret;
}
EXPORT_SYMBOL_GPL(vfio_pci_core_enable);

diff --git a/drivers/vfio/pci/vfio_pci_core.h b/drivers/vfio/pci/vfio_pci_core.h
index 31f3836e606e..2b5ea0db9284 100644
--- a/drivers/vfio/pci/vfio_pci_core.h
+++ b/drivers/vfio/pci/vfio_pci_core.h
@@ -196,15 +196,6 @@ extern u16 vfio_pci_memory_lock_and_enable(struct vfio_pci_core_device *vdev);
extern void vfio_pci_memory_unlock_and_restore(struct vfio_pci_core_device *vdev,
u16 cmd);

-#ifdef CONFIG_VFIO_PCI_IGD
-extern int vfio_pci_igd_init(struct vfio_pci_core_device *vdev);
-#else
-static inline int vfio_pci_igd_init(struct vfio_pci_core_device *vdev)
-{
- return -ENODEV;
-}
-#endif
-
#ifdef CONFIG_S390
extern int vfio_pci_info_zdev_add_caps(struct vfio_pci_core_device *vdev,
struct vfio_info_cap *caps);
--
2.25.4