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

[Max Gurtovoy <mgurtovoy@nvidia.com>]

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@nvidia.com>
---
 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@redhat.com>"
+#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@nvidia.com>
+ */
+
+#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