[PATCH 2/3] drm/xe/vf: Move tile-related VF functions to separate file

Michal Wajdeczko michal.wajdeczko at intel.com
Mon Jun 2 10:33:24 UTC 2025


Some of our VF functions, even if they take a GT pointer, work
only on primary GT and really are tile-related and would be better
to keep them separate from the rest of true GT-oriented functions.
Move them to a file and update to take a tile pointer instead.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
Cc: Tomasz Lis <tomasz.lis at intel.com>
---
 drivers/gpu/drm/xe/Makefile           |   3 +-
 drivers/gpu/drm/xe/xe_ggtt.c          |   4 +-
 drivers/gpu/drm/xe/xe_gt_sriov_vf.c   | 245 --------------------------
 drivers/gpu/drm/xe/xe_gt_sriov_vf.h   |   4 -
 drivers/gpu/drm/xe/xe_sriov_vf.c      |   3 +-
 drivers/gpu/drm/xe/xe_tile_sriov_vf.c | 245 ++++++++++++++++++++++++++
 drivers/gpu/drm/xe/xe_tile_sriov_vf.h |  18 ++
 7 files changed, 269 insertions(+), 253 deletions(-)
 create mode 100644 drivers/gpu/drm/xe/xe_tile_sriov_vf.c
 create mode 100644 drivers/gpu/drm/xe/xe_tile_sriov_vf.h

diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
index e4bf484d4121..f5f5775acdc0 100644
--- a/drivers/gpu/drm/xe/Makefile
+++ b/drivers/gpu/drm/xe/Makefile
@@ -139,7 +139,8 @@ xe-y += \
 	xe_guc_relay.o \
 	xe_memirq.o \
 	xe_sriov.o \
-	xe_sriov_vf.o
+	xe_sriov_vf.o \
+	xe_tile_sriov_vf.o
 
 xe-$(CONFIG_PCI_IOV) += \
 	xe_gt_sriov_pf.o \
diff --git a/drivers/gpu/drm/xe/xe_ggtt.c b/drivers/gpu/drm/xe/xe_ggtt.c
index af8e53014b87..b9a0fd5ccaba 100644
--- a/drivers/gpu/drm/xe/xe_ggtt.c
+++ b/drivers/gpu/drm/xe/xe_ggtt.c
@@ -22,12 +22,12 @@
 #include "xe_device.h"
 #include "xe_gt.h"
 #include "xe_gt_printk.h"
-#include "xe_gt_sriov_vf.h"
 #include "xe_gt_tlb_invalidation.h"
 #include "xe_map.h"
 #include "xe_mmio.h"
 #include "xe_pm.h"
 #include "xe_sriov.h"
+#include "xe_tile_sriov_vf.h"
 #include "xe_wa.h"
 #include "xe_wopcm.h"
 
@@ -258,7 +258,7 @@ int xe_ggtt_init_early(struct xe_ggtt *ggtt)
 		return err;
 
 	if (IS_SRIOV_VF(xe)) {
-		err = xe_gt_sriov_vf_prepare_ggtt(xe_tile_get_gt(ggtt->tile, 0));
+		err = xe_tile_sriov_vf_prepare_ggtt(ggtt->tile);
 		if (err)
 			return err;
 	}
diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_vf.c b/drivers/gpu/drm/xe/xe_gt_sriov_vf.c
index acfb3b1b0832..792523cfa6e6 100644
--- a/drivers/gpu/drm/xe/xe_gt_sriov_vf.c
+++ b/drivers/gpu/drm/xe/xe_gt_sriov_vf.c
@@ -613,168 +613,6 @@ s64 xe_gt_sriov_vf_ggtt_shift(struct xe_gt *gt)
 	return config->ggtt_shift;
 }
 
-static int vf_init_ggtt_balloons(struct xe_gt *gt)
-{
-	struct xe_tile *tile = gt_to_tile(gt);
-	struct xe_ggtt *ggtt = tile->mem.ggtt;
-
-	xe_gt_assert(gt, IS_SRIOV_VF(gt_to_xe(gt)));
-	xe_gt_assert(gt, !xe_gt_is_media_type(gt));
-
-	tile->sriov.vf.ggtt_balloon[0] = xe_ggtt_node_init(ggtt);
-	if (IS_ERR(tile->sriov.vf.ggtt_balloon[0]))
-		return PTR_ERR(tile->sriov.vf.ggtt_balloon[0]);
-
-	tile->sriov.vf.ggtt_balloon[1] = xe_ggtt_node_init(ggtt);
-	if (IS_ERR(tile->sriov.vf.ggtt_balloon[1])) {
-		xe_ggtt_node_fini(tile->sriov.vf.ggtt_balloon[0]);
-		return PTR_ERR(tile->sriov.vf.ggtt_balloon[1]);
-	}
-
-	return 0;
-}
-
-/**
- * xe_gt_sriov_vf_balloon_ggtt_locked - Insert balloon nodes to limit used GGTT address range.
- * @gt: the &xe_gt struct instance
- * Return: 0 on success or a negative error code on failure.
- */
-int xe_gt_sriov_vf_balloon_ggtt_locked(struct xe_gt *gt)
-{
-	struct xe_gt_sriov_vf_selfconfig *config = &gt->sriov.vf.self_config;
-	struct xe_tile *tile = gt_to_tile(gt);
-	struct xe_device *xe = gt_to_xe(gt);
-	u64 start, end;
-	int err;
-
-	xe_gt_assert(gt, IS_SRIOV_VF(xe));
-	xe_gt_assert(gt, !xe_gt_is_media_type(gt));
-	lockdep_assert_held(&tile->mem.ggtt->lock);
-
-	if (!config->ggtt_size)
-		return -ENODATA;
-
-	/*
-	 * VF can only use part of the GGTT as allocated by the PF:
-	 *
-	 *      WOPCM                                  GUC_GGTT_TOP
-	 *      |<------------ Total GGTT size ------------------>|
-	 *
-	 *           VF GGTT base -->|<- size ->|
-	 *
-	 *      +--------------------+----------+-----------------+
-	 *      |////////////////////|   block  |\\\\\\\\\\\\\\\\\|
-	 *      +--------------------+----------+-----------------+
-	 *
-	 *      |<--- balloon[0] --->|<-- VF -->|<-- balloon[1] ->|
-	 */
-
-	start = xe_wopcm_size(xe);
-	end = config->ggtt_base;
-	if (end != start) {
-		err = xe_ggtt_node_insert_balloon_locked(tile->sriov.vf.ggtt_balloon[0],
-							 start, end);
-		if (err)
-			return err;
-	}
-
-	start = config->ggtt_base + config->ggtt_size;
-	end = GUC_GGTT_TOP;
-	if (end != start) {
-		err = xe_ggtt_node_insert_balloon_locked(tile->sriov.vf.ggtt_balloon[1],
-							 start, end);
-		if (err) {
-			xe_ggtt_node_remove_balloon_locked(tile->sriov.vf.ggtt_balloon[0]);
-			return err;
-		}
-	}
-
-	return 0;
-}
-
-static int vf_balloon_ggtt(struct xe_gt *gt)
-{
-	struct xe_ggtt *ggtt = gt_to_tile(gt)->mem.ggtt;
-	int err;
-
-	mutex_lock(&ggtt->lock);
-	err = xe_gt_sriov_vf_balloon_ggtt_locked(gt);
-	mutex_unlock(&ggtt->lock);
-
-	return err;
-}
-
-/**
- * xe_gt_sriov_vf_deballoon_ggtt_locked - Remove balloon nodes.
- * @gt: the &xe_gt struct instance
- */
-void xe_gt_sriov_vf_deballoon_ggtt_locked(struct xe_gt *gt)
-{
-	struct xe_tile *tile = gt_to_tile(gt);
-
-	xe_tile_assert(tile, IS_SRIOV_VF(tile_to_xe(tile)));
-	xe_ggtt_node_remove_balloon_locked(tile->sriov.vf.ggtt_balloon[1]);
-	xe_ggtt_node_remove_balloon_locked(tile->sriov.vf.ggtt_balloon[0]);
-}
-
-static void vf_deballoon_ggtt(struct xe_gt *gt)
-{
-	struct xe_tile *tile = gt_to_tile(gt);
-
-	mutex_lock(&tile->mem.ggtt->lock);
-	xe_gt_sriov_vf_deballoon_ggtt_locked(gt);
-	mutex_unlock(&tile->mem.ggtt->lock);
-}
-
-static void vf_fini_ggtt_balloons(struct xe_gt *gt)
-{
-	struct xe_tile *tile = gt_to_tile(gt);
-
-	xe_gt_assert(gt, IS_SRIOV_VF(gt_to_xe(gt)));
-	xe_gt_assert(gt, !xe_gt_is_media_type(gt));
-
-	xe_ggtt_node_fini(tile->sriov.vf.ggtt_balloon[1]);
-	xe_ggtt_node_fini(tile->sriov.vf.ggtt_balloon[0]);
-}
-
-static void cleanup_ggtt(struct drm_device *drm, void *arg)
-{
-	struct xe_gt *gt = arg;
-
-	vf_deballoon_ggtt(gt);
-	vf_fini_ggtt_balloons(gt);
-}
-
-/**
- * xe_gt_sriov_vf_prepare_ggtt - Prepare a VF's GGTT configuration.
- * @gt: the &xe_gt
- *
- * This function is for VF use only.
- *
- * Return: 0 on success or a negative error code on failure.
- */
-int xe_gt_sriov_vf_prepare_ggtt(struct xe_gt *gt)
-{
-	struct xe_tile *tile = gt_to_tile(gt);
-	struct xe_device *xe = tile_to_xe(tile);
-	int err;
-
-	if (xe_gt_is_media_type(gt))
-		return 0;
-
-	err = vf_init_ggtt_balloons(gt);
-	if (err)
-		return err;
-
-	err = vf_balloon_ggtt(gt);
-	if (err) {
-		vf_fini_ggtt_balloons(gt);
-		return err;
-	}
-
-	return drmm_add_action_or_reset(&xe->drm, cleanup_ggtt, gt);
-}
-
 static int relay_action_handshake(struct xe_gt *gt, u32 *major, u32 *minor)
 {
 	u32 request[VF2PF_HANDSHAKE_REQUEST_MSG_LEN] = {
@@ -870,89 +708,6 @@ int xe_gt_sriov_vf_connect(struct xe_gt *gt)
 	return err;
 }
 
-/**
- * DOC: GGTT nodes shifting during VF post-migration recovery
- *
- * The first fixup applied to the VF KMD structures as part of post-migration
- * recovery is shifting nodes within &xe_ggtt instance. The nodes are moved
- * from range previously assigned to this VF, into newly provisioned area.
- * The changes include balloons, which are resized accordingly.
- *
- * The balloon nodes are there to eliminate unavailable ranges from use: one
- * reserves the GGTT area below the range for current VF, and another one
- * reserves area above.
- *
- * Below is a GGTT layout of example VF, with a certain address range assigned to
- * said VF, and inaccessible areas above and below:
- *
- *  0                                                                        4GiB
- *  |<--------------------------- Total GGTT size ----------------------------->|
- *      WOPCM                                                         GUC_TOP
- *      |<-------------- Area mappable by xe_ggtt instance ---------------->|
- *
- *  +---+---------------------------------+----------+----------------------+---+
- *  |\\\|/////////////////////////////////|  VF mem  |//////////////////////|\\\|
- *  +---+---------------------------------+----------+----------------------+---+
- *
- * Hardware enforced access rules before migration:
- *
- *  |<------- inaccessible for VF ------->|<VF owned>|<-- inaccessible for VF ->|
- *
- * GGTT nodes used for tracking allocations:
- *
- *      |<---------- balloon ------------>|<- nodes->|<----- balloon ------>|
- *
- * After the migration, GGTT area assigned to the VF might have shifted, either
- * to lower or to higher address. But we expect the total size and extra areas to
- * be identical, as migration can only happen between matching platforms.
- * Below is an example of GGTT layout of the VF after migration. Content of the
- * GGTT for VF has been moved to a new area, and we receive its address from GuC:
- *
- *  +---+----------------------+----------+---------------------------------+---+
- *  |\\\|//////////////////////|  VF mem  |/////////////////////////////////|\\\|
- *  +---+----------------------+----------+---------------------------------+---+
- *
- * Hardware enforced access rules after migration:
- *
- *  |<- inaccessible for VF -->|<VF owned>|<------- inaccessible for VF ------->|
- *
- * So the VF has a new slice of GGTT assigned, and during migration process, the
- * memory content was copied to that new area. But the &xe_ggtt nodes are still
- * tracking allocations using the old addresses. The nodes within VF owned area
- * have to be shifted, and balloon nodes need to be resized to properly mask out
- * areas not owned by the VF.
- *
- * Fixed &xe_ggtt nodes used for tracking allocations:
- *
- *     |<------ balloon ------>|<- nodes->|<----------- balloon ----------->|
- *
- * Due to use of GPU profiles, we do not expect the old and new GGTT ares to
- * overlap; but our node shifting will fix addresses properly regardless.
- */
-
-/**
- * xe_gt_sriov_vf_fixup_ggtt_nodes - Shift GGTT allocations to match assigned range.
- * @gt: the &xe_gt struct instance
- * @shift: the shift value
- *
- * Since Global GTT is not virtualized, each VF has an assigned range
- * within the global space. This range might have changed during migration,
- * which requires all memory addresses pointing to GGTT to be shifted.
- */
-void xe_gt_sriov_vf_fixup_ggtt_nodes(struct xe_gt *gt, s64 shift)
-{
-	struct xe_tile *tile = gt_to_tile(gt);
-	struct xe_ggtt *ggtt = tile->mem.ggtt;
-
-	xe_gt_assert(gt, !xe_gt_is_media_type(gt));
-
-	mutex_lock(&ggtt->lock);
-	xe_gt_sriov_vf_deballoon_ggtt_locked(gt);
-	xe_ggtt_shift_nodes_locked(ggtt, shift);
-	xe_gt_sriov_vf_balloon_ggtt_locked(gt);
-	mutex_unlock(&ggtt->lock);
-}
-
 /**
  * xe_gt_sriov_vf_migrated_event_handler - Start a VF migration recovery,
  *   or just mark that a GuC is ready for it.
diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_vf.h b/drivers/gpu/drm/xe/xe_gt_sriov_vf.h
index 2f96ac0c5dca..6250fe774d89 100644
--- a/drivers/gpu/drm/xe/xe_gt_sriov_vf.h
+++ b/drivers/gpu/drm/xe/xe_gt_sriov_vf.h
@@ -17,10 +17,6 @@ int xe_gt_sriov_vf_bootstrap(struct xe_gt *gt);
 int xe_gt_sriov_vf_query_config(struct xe_gt *gt);
 int xe_gt_sriov_vf_connect(struct xe_gt *gt);
 int xe_gt_sriov_vf_query_runtime(struct xe_gt *gt);
-int xe_gt_sriov_vf_prepare_ggtt(struct xe_gt *gt);
-int xe_gt_sriov_vf_balloon_ggtt_locked(struct xe_gt *gt);
-void xe_gt_sriov_vf_deballoon_ggtt_locked(struct xe_gt *gt);
-void xe_gt_sriov_vf_fixup_ggtt_nodes(struct xe_gt *gt, s64 shift);
 int xe_gt_sriov_vf_notify_resfix_done(struct xe_gt *gt);
 void xe_gt_sriov_vf_migrated_event_handler(struct xe_gt *gt);
 
diff --git a/drivers/gpu/drm/xe/xe_sriov_vf.c b/drivers/gpu/drm/xe/xe_sriov_vf.c
index 46466932375c..6526fe450e55 100644
--- a/drivers/gpu/drm/xe/xe_sriov_vf.c
+++ b/drivers/gpu/drm/xe/xe_sriov_vf.c
@@ -15,6 +15,7 @@
 #include "xe_sriov.h"
 #include "xe_sriov_printk.h"
 #include "xe_sriov_vf.h"
+#include "xe_tile_sriov_vf.h"
 
 /**
  * DOC: VF restore procedure in PF KMD and VF KMD
@@ -211,7 +212,7 @@ static bool vf_post_migration_fixup_ggtt_nodes(struct xe_device *xe)
 		shift = xe_gt_sriov_vf_ggtt_shift(gt);
 		if (shift) {
 			need_fixups = true;
-			xe_gt_sriov_vf_fixup_ggtt_nodes(gt, shift);
+			xe_tile_sriov_vf_fixup_ggtt_nodes(tile, shift);
 		}
 	}
 	return need_fixups;
diff --git a/drivers/gpu/drm/xe/xe_tile_sriov_vf.c b/drivers/gpu/drm/xe/xe_tile_sriov_vf.c
new file mode 100644
index 000000000000..88e832894432
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_tile_sriov_vf.c
@@ -0,0 +1,245 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#include <drm/drm_managed.h>
+
+#include "regs/xe_gtt_defs.h"
+
+#include "xe_assert.h"
+#include "xe_ggtt.h"
+#include "xe_gt_sriov_vf.h"
+#include "xe_sriov.h"
+#include "xe_tile_sriov_vf.h"
+#include "xe_wopcm.h"
+
+static int vf_init_ggtt_balloons(struct xe_tile *tile)
+{
+	struct xe_ggtt *ggtt = tile->mem.ggtt;
+
+	xe_tile_assert(tile, IS_SRIOV_VF(tile_to_xe(tile)));
+
+	tile->sriov.vf.ggtt_balloon[0] = xe_ggtt_node_init(ggtt);
+	if (IS_ERR(tile->sriov.vf.ggtt_balloon[0]))
+		return PTR_ERR(tile->sriov.vf.ggtt_balloon[0]);
+
+	tile->sriov.vf.ggtt_balloon[1] = xe_ggtt_node_init(ggtt);
+	if (IS_ERR(tile->sriov.vf.ggtt_balloon[1])) {
+		xe_ggtt_node_fini(tile->sriov.vf.ggtt_balloon[0]);
+		return PTR_ERR(tile->sriov.vf.ggtt_balloon[1]);
+	}
+
+	return 0;
+}
+
+/**
+ * xe_tile_sriov_vf_balloon_ggtt_locked - Insert balloon nodes to limit used GGTT address range.
+ * @tile: the &xe_tile struct instance
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_tile_sriov_vf_balloon_ggtt_locked(struct xe_tile *tile)
+{
+	u64 ggtt_base = xe_gt_sriov_vf_ggtt_base(tile->primary_gt);
+	u64 ggtt_size = xe_gt_sriov_vf_ggtt(tile->primary_gt);
+	struct xe_device *xe = tile_to_xe(tile);
+	u64 start, end;
+	int err;
+
+	xe_tile_assert(tile, IS_SRIOV_VF(xe));
+	xe_tile_assert(tile, ggtt_size);
+	lockdep_assert_held(&tile->mem.ggtt->lock);
+
+	/*
+	 * VF can only use part of the GGTT as allocated by the PF:
+	 *
+	 *      WOPCM                                  GUC_GGTT_TOP
+	 *      |<------------ Total GGTT size ------------------>|
+	 *
+	 *           VF GGTT base -->|<- size ->|
+	 *
+	 *      +--------------------+----------+-----------------+
+	 *      |////////////////////|   block  |\\\\\\\\\\\\\\\\\|
+	 *      +--------------------+----------+-----------------+
+	 *
+	 *      |<--- balloon[0] --->|<-- VF -->|<-- balloon[1] ->|
+	 */
+
+	start = xe_wopcm_size(xe);
+	end = ggtt_base;
+	if (end != start) {
+		err = xe_ggtt_node_insert_balloon_locked(tile->sriov.vf.ggtt_balloon[0],
+							 start, end);
+		if (err)
+			return err;
+	}
+
+	start = ggtt_base + ggtt_size;
+	end = GUC_GGTT_TOP;
+	if (end != start) {
+		err = xe_ggtt_node_insert_balloon_locked(tile->sriov.vf.ggtt_balloon[1],
+							 start, end);
+		if (err) {
+			xe_ggtt_node_remove_balloon_locked(tile->sriov.vf.ggtt_balloon[0]);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+static int vf_balloon_ggtt(struct xe_tile *tile)
+{
+	struct xe_ggtt *ggtt = tile->mem.ggtt;
+	int err;
+
+	mutex_lock(&ggtt->lock);
+	err = xe_tile_sriov_vf_balloon_ggtt_locked(tile);
+	mutex_unlock(&ggtt->lock);
+
+	return err;
+}
+
+/**
+ * xe_tile_sriov_vf_deballoon_ggtt_locked - Remove balloon nodes.
+ * @tile: the &xe_tile struct instance
+ */
+void xe_tile_sriov_vf_deballoon_ggtt_locked(struct xe_tile *tile)
+{
+	xe_tile_assert(tile, IS_SRIOV_VF(tile_to_xe(tile)));
+
+	xe_ggtt_node_remove_balloon_locked(tile->sriov.vf.ggtt_balloon[1]);
+	xe_ggtt_node_remove_balloon_locked(tile->sriov.vf.ggtt_balloon[0]);
+}
+
+static void vf_deballoon_ggtt(struct xe_tile *tile)
+{
+	mutex_lock(&tile->mem.ggtt->lock);
+	xe_tile_sriov_vf_deballoon_ggtt_locked(tile);
+	mutex_unlock(&tile->mem.ggtt->lock);
+}
+
+static void vf_fini_ggtt_balloons(struct xe_tile *tile)
+{
+	xe_tile_assert(tile, IS_SRIOV_VF(tile_to_xe(tile)));
+
+	xe_ggtt_node_fini(tile->sriov.vf.ggtt_balloon[1]);
+	xe_ggtt_node_fini(tile->sriov.vf.ggtt_balloon[0]);
+}
+
+static void cleanup_ggtt(struct drm_device *drm, void *arg)
+{
+	struct xe_tile *tile = arg;
+
+	vf_deballoon_ggtt(tile);
+	vf_fini_ggtt_balloons(tile);
+}
+
+/**
+ * xe_tile_sriov_vf_prepare_ggtt - Prepare a VF's GGTT configuration.
+ * @tile: the &xe_tile
+ *
+ * This function is for VF use only.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_tile_sriov_vf_prepare_ggtt(struct xe_tile *tile)
+{
+	struct xe_device *xe = tile_to_xe(tile);
+	int err;
+
+	err = vf_init_ggtt_balloons(tile);
+	if (err)
+		return err;
+
+	err = vf_balloon_ggtt(tile);
+	if (err) {
+		vf_fini_ggtt_balloons(tile);
+		return err;
+	}
+
+	return drmm_add_action_or_reset(&xe->drm, cleanup_ggtt, tile);
+}
+
+/**
+ * DOC: GGTT nodes shifting during VF post-migration recovery
+ *
+ * The first fixup applied to the VF KMD structures as part of post-migration
+ * recovery is shifting nodes within &xe_ggtt instance. The nodes are moved
+ * from range previously assigned to this VF, into newly provisioned area.
+ * The changes include balloons, which are resized accordingly.
+ *
+ * The balloon nodes are there to eliminate unavailable ranges from use: one
+ * reserves the GGTT area below the range for current VF, and another one
+ * reserves area above.
+ *
+ * Below is a GGTT layout of example VF, with a certain address range assigned to
+ * said VF, and inaccessible areas above and below:
+ *
+ *  0                                                                        4GiB
+ *  |<--------------------------- Total GGTT size ----------------------------->|
+ *      WOPCM                                                         GUC_TOP
+ *      |<-------------- Area mappable by xe_ggtt instance ---------------->|
+ *
+ *  +---+---------------------------------+----------+----------------------+---+
+ *  |\\\|/////////////////////////////////|  VF mem  |//////////////////////|\\\|
+ *  +---+---------------------------------+----------+----------------------+---+
+ *
+ * Hardware enforced access rules before migration:
+ *
+ *  |<------- inaccessible for VF ------->|<VF owned>|<-- inaccessible for VF ->|
+ *
+ * GGTT nodes used for tracking allocations:
+ *
+ *      |<---------- balloon ------------>|<- nodes->|<----- balloon ------>|
+ *
+ * After the migration, GGTT area assigned to the VF might have shifted, either
+ * to lower or to higher address. But we expect the total size and extra areas to
+ * be identical, as migration can only happen between matching platforms.
+ * Below is an example of GGTT layout of the VF after migration. Content of the
+ * GGTT for VF has been moved to a new area, and we receive its address from GuC:
+ *
+ *  +---+----------------------+----------+---------------------------------+---+
+ *  |\\\|//////////////////////|  VF mem  |/////////////////////////////////|\\\|
+ *  +---+----------------------+----------+---------------------------------+---+
+ *
+ * Hardware enforced access rules after migration:
+ *
+ *  |<- inaccessible for VF -->|<VF owned>|<------- inaccessible for VF ------->|
+ *
+ * So the VF has a new slice of GGTT assigned, and during migration process, the
+ * memory content was copied to that new area. But the &xe_ggtt nodes are still
+ * tracking allocations using the old addresses. The nodes within VF owned area
+ * have to be shifted, and balloon nodes need to be resized to properly mask out
+ * areas not owned by the VF.
+ *
+ * Fixed &xe_ggtt nodes used for tracking allocations:
+ *
+ *     |<------ balloon ------>|<- nodes->|<----------- balloon ----------->|
+ *
+ * Due to use of GPU profiles, we do not expect the old and new GGTT ares to
+ * overlap; but our node shifting will fix addresses properly regardless.
+ */
+
+/**
+ * xe_tile_sriov_vf_fixup_ggtt_nodes - Shift GGTT allocations to match assigned range.
+ * @tile: the &xe_tile struct instance
+ * @shift: the shift value
+ *
+ * Since Global GTT is not virtualized, each VF has an assigned range
+ * within the global space. This range might have changed during migration,
+ * which requires all memory addresses pointing to GGTT to be shifted.
+ */
+void xe_tile_sriov_vf_fixup_ggtt_nodes(struct xe_tile *tile, s64 shift)
+{
+	struct xe_ggtt *ggtt = tile->mem.ggtt;
+
+	mutex_lock(&ggtt->lock);
+
+	xe_tile_sriov_vf_deballoon_ggtt_locked(tile);
+	xe_ggtt_shift_nodes_locked(ggtt, shift);
+	xe_tile_sriov_vf_balloon_ggtt_locked(tile);
+
+	mutex_unlock(&ggtt->lock);
+}
diff --git a/drivers/gpu/drm/xe/xe_tile_sriov_vf.h b/drivers/gpu/drm/xe/xe_tile_sriov_vf.h
new file mode 100644
index 000000000000..93eb043171e8
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_tile_sriov_vf.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#ifndef _XE_TILE_SRIOV_VF_H_
+#define _XE_TILE_SRIOV_VF_H_
+
+#include <linux/types.h>
+
+struct xe_tile;
+
+int xe_tile_sriov_vf_prepare_ggtt(struct xe_tile *tile);
+int xe_tile_sriov_vf_balloon_ggtt_locked(struct xe_tile *tile);
+void xe_tile_sriov_vf_deballoon_ggtt_locked(struct xe_tile *tile);
+void xe_tile_sriov_vf_fixup_ggtt_nodes(struct xe_tile *tile, s64 shift);
+
+#endif
-- 
2.47.1



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