[PATCH 05/22] drm/xe/svm: add helper to retrieve svm range from address

[Oak Zeng <oak.zeng@intel.com>]

All valid virtual address range are maintained in svm's
range_tree. This functions iterate svm's range tree and
return the svm range that contains specific address.

Signed-off-by: Oak Zeng <oak.zeng@intel.com>
Cc: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@intel.com>
Cc: Brian Welty <brian.welty@intel.com>
---
 drivers/gpu/drm/xe/xe_svm.h       |  2 ++
 drivers/gpu/drm/xe/xe_svm_range.c | 32 +++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 drivers/gpu/drm/xe/xe_svm_range.c

diff --git a/drivers/gpu/drm/xe/xe_svm.h b/drivers/gpu/drm/xe/xe_svm.h
index cd3cf92f3784..3ed106ecc02b 100644
--- a/drivers/gpu/drm/xe/xe_svm.h
+++ b/drivers/gpu/drm/xe/xe_svm.h
@@ -67,4 +67,6 @@ struct xe_svm_range {
 void xe_destroy_svm(struct xe_svm *svm);
 struct xe_svm *xe_create_svm(struct xe_vm *vm);
 struct xe_svm *xe_lookup_svm_by_mm(struct mm_struct *mm);
+struct xe_svm_range *xe_svm_range_from_addr(struct xe_svm *svm,
+								unsigned long addr);
 #endif
diff --git a/drivers/gpu/drm/xe/xe_svm_range.c b/drivers/gpu/drm/xe/xe_svm_range.c
new file mode 100644
index 000000000000..d8251d38f65e
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_svm_range.c
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#include <linux/interval_tree.h>
+#include <linux/container_of.h>
+#include <linux/mutex.h>
+#include "xe_svm.h"
+
+/**
+ * xe_svm_range_from_addr() - retrieve svm_range contains a virtual address
+ *
+ * @svm: svm that the virtual address belongs to
+ * @addr: the virtual address to retrieve svm_range for
+ *
+ * return the svm range found,
+ * or NULL if no range found
+ */
+struct xe_svm_range *xe_svm_range_from_addr(struct xe_svm *svm,
+									unsigned long addr)
+{
+	struct interval_tree_node *node;
+
+	mutex_lock(&svm->mutex);
+	node = interval_tree_iter_first(&svm->range_tree, addr, addr);
+	mutex_unlock(&svm->mutex);
+	if (!node)
+		return NULL;
+
+	return container_of(node, struct xe_svm_range, inode);
+}
-- 
2.26.3