[RFC PATCH 07/28] drm/xe: Add SVM init / fini to faulting VMs

[Matthew Brost <matthew.brost@xxxxxxxxx>]

Add SVM init / fini to faulting VMs. Minimual implementation.

Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
---
 drivers/gpu/drm/xe/Makefile      |  1 +
 drivers/gpu/drm/xe/xe_svm.c      | 40 ++++++++++++++++++++++++++++++++
 drivers/gpu/drm/xe/xe_svm.h      | 14 +++++++++++
 drivers/gpu/drm/xe/xe_vm.c       | 10 ++++++++
 drivers/gpu/drm/xe/xe_vm_types.h |  7 ++++++
 5 files changed, 72 insertions(+)
 create mode 100644 drivers/gpu/drm/xe/xe_svm.c
 create mode 100644 drivers/gpu/drm/xe/xe_svm.h

diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
index b8fc2ee58f1a..17bd7cfc9a62 100644
--- a/drivers/gpu/drm/xe/Makefile
+++ b/drivers/gpu/drm/xe/Makefile
@@ -94,6 +94,7 @@ xe-y += drm_gpusvm.o \
 	xe_sa.o \
 	xe_sched_job.o \
 	xe_step.o \
+	xe_svm.o \
 	xe_sync.o \
 	xe_tile.o \
 	xe_tile_sysfs.o \
diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
new file mode 100644
index 000000000000..7166100e3298
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_svm.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2024 Intel Corporation
+ */
+
+#include "drm_gpusvm.h"
+
+#include "xe_svm.h"
+#include "xe_vm.h"
+#include "xe_vm_types.h"
+
+static void xe_svm_invalidate(struct drm_gpusvm *gpusvm,
+			      struct drm_gpusvm_notifier *notifier,
+			      const struct mmu_notifier_range *mmu_range)
+{
+	/* TODO: Implement */
+}
+
+static const struct drm_gpusvm_ops gpusvm_ops = {
+	.invalidate = xe_svm_invalidate,
+};
+
+static const u64 fault_chunk_sizes[] = {
+	SZ_2M,
+	SZ_64K,
+	SZ_4K,
+};
+
+int xe_svm_init(struct xe_vm *vm)
+{
+	return drm_gpusvm_init(&vm->svm.gpusvm, "Xe SVM", &vm->xe->drm,
+			       current->mm, NULL, 0, vm->size,
+			       SZ_512M, &gpusvm_ops, fault_chunk_sizes,
+			       ARRAY_SIZE(fault_chunk_sizes));
+}
+
+void xe_svm_fini(struct xe_vm *vm)
+{
+	drm_gpusvm_fini(&vm->svm.gpusvm);
+}
diff --git a/drivers/gpu/drm/xe/xe_svm.h b/drivers/gpu/drm/xe/xe_svm.h
new file mode 100644
index 000000000000..4982d9168095
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_svm.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2024 Intel Corporation
+ */
+
+#ifndef _XE_SVM_H_
+#define _XE_SVM_H_
+
+struct xe_vm;
+
+int xe_svm_init(struct xe_vm *vm);
+void xe_svm_fini(struct xe_vm *vm);
+
+#endif
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index 5ec160561662..17ad6a533b2f 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -35,6 +35,7 @@
 #include "xe_preempt_fence.h"
 #include "xe_pt.h"
 #include "xe_res_cursor.h"
+#include "xe_svm.h"
 #include "xe_sync.h"
 #include "xe_trace_bo.h"
 #include "xe_wa.h"
@@ -1503,6 +1504,12 @@ struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags)
 		}
 	}
 
+	if (flags & XE_VM_FLAG_FAULT_MODE) {
+		err = xe_svm_init(vm);
+		if (err)
+			goto err_close;
+	}
+
 	if (number_tiles > 1)
 		vm->composite_fence_ctx = dma_fence_context_alloc(1);
 
@@ -1616,6 +1623,9 @@ void xe_vm_close_and_put(struct xe_vm *vm)
 		xe_vma_destroy_unlocked(vma);
 	}
 
+	if (xe_vm_in_fault_mode(vm))
+		xe_svm_fini(vm);
+
 	up_write(&vm->lock);
 
 	mutex_lock(&xe->usm.lock);
diff --git a/drivers/gpu/drm/xe/xe_vm_types.h b/drivers/gpu/drm/xe/xe_vm_types.h
index 1764781c376b..bd1c0e368238 100644
--- a/drivers/gpu/drm/xe/xe_vm_types.h
+++ b/drivers/gpu/drm/xe/xe_vm_types.h
@@ -6,6 +6,7 @@
 #ifndef _XE_VM_TYPES_H_
 #define _XE_VM_TYPES_H_
 
+#include "drm_gpusvm.h"
 #include <drm/drm_gpuvm.h>
 
 #include <linux/dma-resv.h>
@@ -140,6 +141,12 @@ struct xe_vm {
 	/** @gpuvm: base GPUVM used to track VMAs */
 	struct drm_gpuvm gpuvm;
 
+	/** @svm: Shared virtual memory state */
+	struct {
+		/** @svm.gpusvm: base GPUSVM used to track fault allocations */
+		struct drm_gpusvm gpusvm;
+	} svm;
+
 	struct xe_device *xe;
 
 	/* exec queue used for (un)binding vma's */
-- 
2.34.1