1 files changed, 146 insertions, 0 deletions
diff --git a/drivers/misc/vmw_vmci/vmci_handle_array.c b/drivers/misc/vmw_vmci/vmci_handle_array.c
new file mode 100644
index 0000000000..de7fee7ead
--- /dev/null
+++ b/drivers/misc/vmw_vmci/vmci_handle_array.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * VMware VMCI Driver
+ *
+ * Copyright (C) 2012 VMware, Inc. All rights reserved.
+ */
+
+#include <linux/slab.h>
+#include "vmci_handle_array.h"
+
+static size_t handle_arr_calc_size(u32 capacity)
+{
+	return VMCI_HANDLE_ARRAY_HEADER_SIZE +
+	    capacity * sizeof(struct vmci_handle);
+}
+
+struct vmci_handle_arr *vmci_handle_arr_create(u32 capacity, u32 max_capacity)
+{
+	struct vmci_handle_arr *array;
+
+	if (max_capacity == 0 || capacity > max_capacity)
+		return NULL;
+
+	if (capacity == 0)
+		capacity = min((u32)VMCI_HANDLE_ARRAY_DEFAULT_CAPACITY,
+			       max_capacity);
+
+	array = kmalloc(handle_arr_calc_size(capacity), GFP_ATOMIC);
+	if (!array)
+		return NULL;
+
+	array->capacity = capacity;
+	array->max_capacity = max_capacity;
+	array->size = 0;
+
+	return array;
+}
+
+void vmci_handle_arr_destroy(struct vmci_handle_arr *array)
+{
+	kfree(array);
+}
+
+int vmci_handle_arr_append_entry(struct vmci_handle_arr **array_ptr,
+				 struct vmci_handle handle)
+{
+	struct vmci_handle_arr *array = *array_ptr;
+
+	if (unlikely(array->size >= array->capacity)) {
+		/* reallocate. */
+		struct vmci_handle_arr *new_array;
+		u32 capacity_bump = min(array->max_capacity - array->capacity,
+					array->capacity);
+		size_t new_size = handle_arr_calc_size(array->capacity +
+						       capacity_bump);
+
+		if (array->size >= array->max_capacity)
+			return VMCI_ERROR_NO_MEM;
+
+		new_array = krealloc(array, new_size, GFP_ATOMIC);
+		if (!new_array)
+			return VMCI_ERROR_NO_MEM;
+
+		new_array->capacity += capacity_bump;
+		*array_ptr = array = new_array;
+	}
+
+	array->entries[array->size] = handle;
+	array->size++;
+
+	return VMCI_SUCCESS;
+}
+
+/*
+ * Handle that was removed, VMCI_INVALID_HANDLE if entry not found.
+ */
+struct vmci_handle vmci_handle_arr_remove_entry(struct vmci_handle_arr *array,
+						struct vmci_handle entry_handle)
+{
+	struct vmci_handle handle = VMCI_INVALID_HANDLE;
+	u32 i;
+
+	for (i = 0; i < array->size; i++) {
+		if (vmci_handle_is_equal(array->entries[i], entry_handle)) {
+			handle = array->entries[i];
+			array->size--;
+			array->entries[i] = array->entries[array->size];
+			array->entries[array->size] = VMCI_INVALID_HANDLE;
+			break;
+		}
+	}
+
+	return handle;
+}
+
+/*
+ * Handle that was removed, VMCI_INVALID_HANDLE if array was empty.
+ */
+struct vmci_handle vmci_handle_arr_remove_tail(struct vmci_handle_arr *array)
+{
+	struct vmci_handle handle = VMCI_INVALID_HANDLE;
+
+	if (array->size) {
+		array->size--;
+		handle = array->entries[array->size];
+		array->entries[array->size] = VMCI_INVALID_HANDLE;
+	}
+
+	return handle;
+}
+
+/*
+ * Handle at given index, VMCI_INVALID_HANDLE if invalid index.
+ */
+struct vmci_handle
+vmci_handle_arr_get_entry(const struct vmci_handle_arr *array, u32 index)
+{
+	if (unlikely(index >= array->size))
+		return VMCI_INVALID_HANDLE;
+
+	return array->entries[index];
+}
+
+bool vmci_handle_arr_has_entry(const struct vmci_handle_arr *array,
+			       struct vmci_handle entry_handle)
+{
+	u32 i;
+
+	for (i = 0; i < array->size; i++)
+		if (vmci_handle_is_equal(array->entries[i], entry_handle))
+			return true;
+
+	return false;
+}
+
+/*
+ * NULL if the array is empty. Otherwise, a pointer to the array
+ * of VMCI handles in the handle array.
+ */
+struct vmci_handle *vmci_handle_arr_get_handles(struct vmci_handle_arr *array)
+{
+	if (array->size)
+		return array->entries;
+
+	return NULL;
+}