drm/xe/pf: Export helpers for VFIO

Device specific VFIO driver variant for Xe will implement VF migration.
Export everything that's needed for migration ops.

Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patch.msgid.link/20251127093934.1462188-4-michal.winiarski@intel.com
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
(cherry picked from commit 17f22465c5a5573724c942ca7147b4024631ef87)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>

drivers/gpu/drm/xe/Makefile

@@ -184,6 +184,10 @@ xe-$(CONFIG_PCI_IOV) += \
 	xe_sriov_pf_sysfs.o \
 	xe_tile_sriov_pf_debugfs.o
 
+ifeq ($(CONFIG_PCI_IOV),y)
+	xe-$(CONFIG_XE_VFIO_PCI) += xe_sriov_vfio.o
+endif
+
 # include helpers for tests even when XE is built-in
 ifdef CONFIG_DRM_XE_KUNIT_TEST
 xe-y += tests/xe_kunit_helpers.o

drivers/gpu/drm/xe/xe_sriov_vfio.c

@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#include <drm/intel/xe_sriov_vfio.h>
+#include <linux/cleanup.h>
+
+#include "xe_pci.h"
+#include "xe_pm.h"
+#include "xe_sriov_pf_control.h"
+#include "xe_sriov_pf_helpers.h"
+#include "xe_sriov_pf_migration.h"
+
+struct xe_device *xe_sriov_vfio_get_pf(struct pci_dev *pdev)
+{
+	return xe_pci_to_pf_device(pdev);
+}
+EXPORT_SYMBOL_FOR_MODULES(xe_sriov_vfio_get_pf, "xe-vfio-pci");
+
+bool xe_sriov_vfio_migration_supported(struct xe_device *xe)
+{
+	if (!IS_SRIOV_PF(xe))
+		return -EPERM;
+
+	return xe_sriov_pf_migration_supported(xe);
+}
+EXPORT_SYMBOL_FOR_MODULES(xe_sriov_vfio_migration_supported, "xe-vfio-pci");
+
+#define DEFINE_XE_SRIOV_VFIO_FUNCTION(_type, _func, _impl)			\
+_type xe_sriov_vfio_##_func(struct xe_device *xe, unsigned int vfid)		\
+{										\
+	if (!IS_SRIOV_PF(xe))							\
+		return -EPERM;							\
+	if (vfid == PFID || vfid > xe_sriov_pf_num_vfs(xe))			\
+		return -EINVAL;							\
+										\
+	guard(xe_pm_runtime_noresume)(xe);					\
+										\
+	return xe_sriov_pf_##_impl(xe, vfid);					\
+}										\
+EXPORT_SYMBOL_FOR_MODULES(xe_sriov_vfio_##_func, "xe-vfio-pci")
+
+DEFINE_XE_SRIOV_VFIO_FUNCTION(int, wait_flr_done, control_wait_flr);
+DEFINE_XE_SRIOV_VFIO_FUNCTION(int, suspend_device, control_pause_vf);
+DEFINE_XE_SRIOV_VFIO_FUNCTION(int, resume_device, control_resume_vf);
+DEFINE_XE_SRIOV_VFIO_FUNCTION(int, stop_copy_enter, control_trigger_save_vf);
+DEFINE_XE_SRIOV_VFIO_FUNCTION(int, stop_copy_exit, control_finish_save_vf);
+DEFINE_XE_SRIOV_VFIO_FUNCTION(int, resume_data_enter, control_trigger_restore_vf);
+DEFINE_XE_SRIOV_VFIO_FUNCTION(int, resume_data_exit, control_finish_restore_vf);
+DEFINE_XE_SRIOV_VFIO_FUNCTION(int, error, control_stop_vf);
+DEFINE_XE_SRIOV_VFIO_FUNCTION(ssize_t, stop_copy_size, migration_size);
+
+ssize_t xe_sriov_vfio_data_read(struct xe_device *xe, unsigned int vfid,
+				char __user *buf, size_t len)
+{
+	if (!IS_SRIOV_PF(xe))
+		return -EPERM;
+	if (vfid == PFID || vfid > xe_sriov_pf_num_vfs(xe))
+		return -EINVAL;
+
+	guard(xe_pm_runtime_noresume)(xe);
+
+	return xe_sriov_pf_migration_read(xe, vfid, buf, len);
+}
+EXPORT_SYMBOL_FOR_MODULES(xe_sriov_vfio_data_read, "xe-vfio-pci");
+
+ssize_t xe_sriov_vfio_data_write(struct xe_device *xe, unsigned int vfid,
+				 const char __user *buf, size_t len)
+{
+	if (!IS_SRIOV_PF(xe))
+		return -EPERM;
+	if (vfid == PFID || vfid > xe_sriov_pf_num_vfs(xe))
+		return -EINVAL;
+
+	guard(xe_pm_runtime_noresume)(xe);
+
+	return xe_sriov_pf_migration_write(xe, vfid, buf, len);
+}
+EXPORT_SYMBOL_FOR_MODULES(xe_sriov_vfio_data_write, "xe-vfio-pci");

include/drm/intel/xe_sriov_vfio.h

@@ -0,0 +1,143 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#ifndef _XE_SRIOV_VFIO_H_
+#define _XE_SRIOV_VFIO_H_
+
+#include <linux/types.h>
+
+struct pci_dev;
+struct xe_device;
+
+/**
+ * xe_sriov_vfio_get_pf() - Get PF &xe_device.
+ * @pdev: the VF &pci_dev device
+ *
+ * Return: pointer to PF &xe_device, NULL otherwise.
+ */
+struct xe_device *xe_sriov_vfio_get_pf(struct pci_dev *pdev);
+
+/**
+ * xe_sriov_vfio_migration_supported() - Check if migration is supported.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ *
+ * Return: true if migration is supported, false otherwise.
+ */
+bool xe_sriov_vfio_migration_supported(struct xe_device *xe);
+
+/**
+ * xe_sriov_vfio_wait_flr_done() - Wait for VF FLR completion.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * This function will wait until VF FLR is processed by PF on all tiles (or
+ * until timeout occurs).
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_vfio_wait_flr_done(struct xe_device *xe, unsigned int vfid);
+
+/**
+ * xe_sriov_vfio_suspend_device() - Suspend VF.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * This function will pause VF on all tiles/GTs.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_vfio_suspend_device(struct xe_device *xe, unsigned int vfid);
+
+/**
+ * xe_sriov_vfio_resume_device() - Resume VF.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * This function will resume VF on all tiles.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_vfio_resume_device(struct xe_device *xe, unsigned int vfid);
+
+/**
+ * xe_sriov_vfio_stop_copy_enter() - Initiate a VF device migration data save.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_vfio_stop_copy_enter(struct xe_device *xe, unsigned int vfid);
+
+/**
+ * xe_sriov_vfio_stop_copy_exit() - Finish a VF device migration data save.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_vfio_stop_copy_exit(struct xe_device *xe, unsigned int vfid);
+
+/**
+ * xe_sriov_vfio_resume_data_enter() - Initiate a VF device migration data restore.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_vfio_resume_data_enter(struct xe_device *xe, unsigned int vfid);
+
+/**
+ * xe_sriov_vfio_resume_data_exit() - Finish a VF device migration data restore.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_vfio_resume_data_exit(struct xe_device *xe, unsigned int vfid);
+
+/**
+ * xe_sriov_vfio_error() - Move VF device to error state.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * Reset is needed to move it out of error state.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_vfio_error(struct xe_device *xe, unsigned int vfid);
+
+/**
+ * xe_sriov_vfio_data_read() - Read migration data from the VF device.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ * @buf: start address of userspace buffer
+ * @len: requested read size from userspace
+ *
+ * Return: number of bytes that has been successfully read,
+ *	   0 if no more migration data is available, -errno on failure.
+ */
+ssize_t xe_sriov_vfio_data_read(struct xe_device *xe, unsigned int vfid,
+				char __user *buf, size_t len);
+/**
+ * xe_sriov_vfio_data_write() - Write migration data to the VF device.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ * @buf: start address of userspace buffer
+ * @len: requested write size from userspace
+ *
+ * Return: number of bytes that has been successfully written, -errno on failure.
+ */
+ssize_t xe_sriov_vfio_data_write(struct xe_device *xe, unsigned int vfid,
+				 const char __user *buf, size_t len);
+/**
+ * xe_sriov_vfio_stop_copy_size() - Get a size estimate of VF device migration data.
+ * @xe: the PF &xe_device obtained by calling xe_sriov_vfio_get_pf()
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * Return: migration data size in bytes or a negative error code on failure.
+ */
+ssize_t xe_sriov_vfio_stop_copy_size(struct xe_device *xe, unsigned int vfid);
+
+#endif