[RFC 21/29] drm/xe: Allow CPU address mirror VMA unbind with gpu bindings for madvise

[Himal Prasad Ghimiray]

In the case of the MADVISE ioctl, if the start or end addresses fall
within a VMA and existing SVM ranges are present, remove the existing
SVM mappings. Then, continue with ops_parse to create new VMAs by REMAP
unmapping of old one.

Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray at intel.com>
---
 drivers/gpu/drm/xe/xe_svm.c | 25 +++++++++++++++++++++++++
 drivers/gpu/drm/xe/xe_svm.h |  7 +++++++
 drivers/gpu/drm/xe/xe_vm.c  | 18 +++++++++++++++++-
 3 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
index 5a4cb14d608e..b181b9bbfa5e 100644
--- a/drivers/gpu/drm/xe/xe_svm.c
+++ b/drivers/gpu/drm/xe/xe_svm.c
@@ -821,6 +821,31 @@ bool xe_svm_has_mapping(struct xe_vm *vm, u64 start, u64 end)
 	return drm_gpusvm_has_mapping(&vm->svm.gpusvm, start, end);
 }
 
+/**
+ * xe_svm_range_clean_if_addr_within - Clean SVM mappings and ranges
+ * @start: start addr
+ * @end: end addr
+ *
+ * This function cleans up svm ranges if start or end address are inside them.
+ */
+void xe_svm_range_clean_if_addr_within(struct xe_vm *vm, u64 start, u64 end)
+{
+	struct drm_gpusvm_notifier *notifier, *next;
+
+	drm_gpusvm_for_each_notifier_safe(notifier, next, &vm->svm.gpusvm, start, end) {
+		struct drm_gpusvm_range *range, *__next;
+
+		drm_gpusvm_for_each_range_safe(range, __next, notifier, start, end) {
+			if (start > drm_gpusvm_range_start(range) ||
+			    end < drm_gpusvm_range_end(range)) {
+				if (IS_DGFX(vm->xe) && xe_svm_range_in_vram(to_xe_range(range)))
+					drm_gpusvm_range_evict(&vm->svm.gpusvm, range);
+				__xe_svm_garbage_collector(vm, to_xe_range(range));
+			}
+		}
+	}
+}
+
 /**
  * xe_svm_bo_evict() - SVM evict BO to system memory
  * @bo: BO to evict
diff --git a/drivers/gpu/drm/xe/xe_svm.h b/drivers/gpu/drm/xe/xe_svm.h
index 6bb358bf62ad..d57d7cc851ee 100644
--- a/drivers/gpu/drm/xe/xe_svm.h
+++ b/drivers/gpu/drm/xe/xe_svm.h
@@ -82,6 +82,8 @@ struct xe_svm_range *xe_svm_range_find_or_insert(struct xe_vm *vm, u64 addr,
 
 int xe_svm_range_get_pages(struct xe_vm *vm, struct xe_svm_range *range,
 			   struct drm_gpusvm_ctx *ctx);
+
+void xe_svm_range_clean_if_addr_within(struct xe_vm *vm, u64 start, u64 end);
 #else
 static inline bool xe_svm_range_pages_valid(struct xe_svm_range *range)
 {
@@ -157,6 +159,11 @@ int xe_svm_range_get_pages(struct xe_vm *vm, struct xe_svm_range *range,
 	return -EINVAL;
 }
 
+static inline
+void xe_svm_range_clean_if_addr_within(struct xe_vm *vm, u64 start, u64 end)
+{
+}
+
 #endif
 
 /**
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index b24bd078aeec..f3e9c3f31fe7 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -2341,6 +2341,22 @@ vm_bind_ioctl_ops_create(struct xe_vm *vm, struct xe_vma_ops *vops,
 				DRM_XE_VM_BIND_FLAG_CPU_ADDR_MIRROR;
 			op->map.dumpable = flags & DRM_XE_VM_BIND_FLAG_DUMPABLE;
 			op->map.pat_index = pat_index;
+		} else if (__op->op == DRM_GPUVA_OP_REMAP) {
+			struct xe_vma *old =
+				gpuva_to_vma(op->base.remap.unmap->va);
+			u64 start = xe_vma_start(old), end = xe_vma_end(old);
+
+			if (op->base.remap.prev)
+				start = op->base.remap.prev->va.addr +
+					op->base.remap.prev->va.range;
+			if (op->base.remap.next)
+				end = op->base.remap.next->va.addr;
+
+			if (xe_vma_is_cpu_addr_mirror(old) &&
+			    xe_svm_has_mapping(vm, start, end)) {
+				drm_gpuva_ops_free(&vm->gpuvm, ops);
+				return ERR_PTR(-EBUSY);
+			}
 		} else if (__op->op == DRM_GPUVA_OP_PREFETCH) {
 			struct xe_vma *vma = gpuva_to_vma(op->base.prefetch.va);
 
@@ -2621,7 +2637,7 @@ static int vm_bind_ioctl_ops_parse(struct xe_vm *vm, struct drm_gpuva_ops *ops,
 
 			if (xe_vma_is_cpu_addr_mirror(old) &&
 			    xe_svm_has_mapping(vm, start, end))
-				return -EBUSY;
+				xe_svm_range_clean_if_addr_within(vm, start, end);
 
 			op->remap.start = xe_vma_start(old);
 			op->remap.range = xe_vma_size(old);
-- 
2.34.1