Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 390 insertions, 0 deletions

diff --git a/include/kunit/resource.h b/include/kunit/resource.h
new file mode 100644
index 000000000..cf6fb8f2a
--- /dev/null
+++ b/include/kunit/resource.h
@@ -0,0 +1,390 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * KUnit resource API for test managed resources (allocations, etc.).
+ *
+ * Copyright (C) 2022, Google LLC.
+ * Author: Daniel Latypov <dlatypov@google.com>
+ */
+
+#ifndef _KUNIT_RESOURCE_H
+#define _KUNIT_RESOURCE_H
+
+#include <kunit/test.h>
+
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+struct kunit_resource;
+
+typedef int (*kunit_resource_init_t)(struct kunit_resource *, void *);
+typedef void (*kunit_resource_free_t)(struct kunit_resource *);
+
+/**
+ * struct kunit_resource - represents a *test managed resource*
+ * @data: for the user to store arbitrary data.
+ * @name: optional name
+ * @free: a user supplied function to free the resource.
+ *
+ * Represents a *test managed resource*, a resource which will automatically be
+ * cleaned up at the end of a test case. This cleanup is performed by the 'free'
+ * function. The struct kunit_resource itself is freed automatically with
+ * kfree() if it was allocated by KUnit (e.g., by kunit_alloc_resource()), but
+ * must be freed by the user otherwise.
+ *
+ * Resources are reference counted so if a resource is retrieved via
+ * kunit_alloc_and_get_resource() or kunit_find_resource(), we need
+ * to call kunit_put_resource() to reduce the resource reference count
+ * when finished with it.  Note that kunit_alloc_resource() does not require a
+ * kunit_resource_put() because it does not retrieve the resource itself.
+ *
+ * Example:
+ *
+ * .. code-block:: c
+ *
+ *	struct kunit_kmalloc_params {
+ *		size_t size;
+ *		gfp_t gfp;
+ *	};
+ *
+ *	static int kunit_kmalloc_init(struct kunit_resource *res, void *context)
+ *	{
+ *		struct kunit_kmalloc_params *params = context;
+ *		res->data = kmalloc(params->size, params->gfp);
+ *
+ *		if (!res->data)
+ *			return -ENOMEM;
+ *
+ *		return 0;
+ *	}
+ *
+ *	static void kunit_kmalloc_free(struct kunit_resource *res)
+ *	{
+ *		kfree(res->data);
+ *	}
+ *
+ *	void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp)
+ *	{
+ *		struct kunit_kmalloc_params params;
+ *
+ *		params.size = size;
+ *		params.gfp = gfp;
+ *
+ *		return kunit_alloc_resource(test, kunit_kmalloc_init,
+ *			kunit_kmalloc_free, &params);
+ *	}
+ *
+ * Resources can also be named, with lookup/removal done on a name
+ * basis also.  kunit_add_named_resource(), kunit_find_named_resource()
+ * and kunit_destroy_named_resource().  Resource names must be
+ * unique within the test instance.
+ */
+struct kunit_resource {
+	void *data;
+	const char *name;
+	kunit_resource_free_t free;
+
+	/* private: internal use only. */
+	struct kref refcount;
+	struct list_head node;
+	bool should_kfree;
+};
+
+/**
+ * kunit_get_resource() - Hold resource for use.  Should not need to be used
+ *			  by most users as we automatically get resources
+ *			  retrieved by kunit_find_resource*().
+ * @res: resource
+ */
+static inline void kunit_get_resource(struct kunit_resource *res)
+{
+	kref_get(&res->refcount);
+}
+
+/*
+ * Called when refcount reaches zero via kunit_put_resource();
+ * should not be called directly.
+ */
+static inline void kunit_release_resource(struct kref *kref)
+{
+	struct kunit_resource *res = container_of(kref, struct kunit_resource,
+						  refcount);
+
+	if (res->free)
+		res->free(res);
+
+	/* 'res' is valid here, as if should_kfree is set, res->free may not free
+	 * 'res' itself, just res->data
+	 */
+	if (res->should_kfree)
+		kfree(res);
+}
+
+/**
+ * kunit_put_resource() - When caller is done with retrieved resource,
+ *			  kunit_put_resource() should be called to drop
+ *			  reference count.  The resource list maintains
+ *			  a reference count on resources, so if no users
+ *			  are utilizing a resource and it is removed from
+ *			  the resource list, it will be freed via the
+ *			  associated free function (if any).  Only
+ *			  needs to be used if we alloc_and_get() or
+ *			  find() resource.
+ * @res: resource
+ */
+static inline void kunit_put_resource(struct kunit_resource *res)
+{
+	kref_put(&res->refcount, kunit_release_resource);
+}
+
+/**
+ * __kunit_add_resource() - Internal helper to add a resource.
+ *
+ * res->should_kfree is not initialised.
+ * @test: The test context object.
+ * @init: a user-supplied function to initialize the result (if needed).  If
+ *        none is supplied, the resource data value is simply set to @data.
+ *	  If an init function is supplied, @data is passed to it instead.
+ * @free: a user-supplied function to free the resource (if needed).
+ * @res: The resource.
+ * @data: value to pass to init function or set in resource data field.
+ */
+int __kunit_add_resource(struct kunit *test,
+			 kunit_resource_init_t init,
+			 kunit_resource_free_t free,
+			 struct kunit_resource *res,
+			 void *data);
+
+/**
+ * kunit_add_resource() - Add a *test managed resource*.
+ * @test: The test context object.
+ * @init: a user-supplied function to initialize the result (if needed).  If
+ *        none is supplied, the resource data value is simply set to @data.
+ *	  If an init function is supplied, @data is passed to it instead.
+ * @free: a user-supplied function to free the resource (if needed).
+ * @res: The resource.
+ * @data: value to pass to init function or set in resource data field.
+ */
+static inline int kunit_add_resource(struct kunit *test,
+				     kunit_resource_init_t init,
+				     kunit_resource_free_t free,
+				     struct kunit_resource *res,
+				     void *data)
+{
+	res->should_kfree = false;
+	return __kunit_add_resource(test, init, free, res, data);
+}
+
+static inline struct kunit_resource *
+kunit_find_named_resource(struct kunit *test, const char *name);
+
+/**
+ * kunit_add_named_resource() - Add a named *test managed resource*.
+ * @test: The test context object.
+ * @init: a user-supplied function to initialize the resource data, if needed.
+ * @free: a user-supplied function to free the resource data, if needed.
+ * @res: The resource.
+ * @name: name to be set for resource.
+ * @data: value to pass to init function or set in resource data field.
+ */
+static inline int kunit_add_named_resource(struct kunit *test,
+					   kunit_resource_init_t init,
+					   kunit_resource_free_t free,
+					   struct kunit_resource *res,
+					   const char *name,
+					   void *data)
+{
+	struct kunit_resource *existing;
+
+	if (!name)
+		return -EINVAL;
+
+	existing = kunit_find_named_resource(test, name);
+	if (existing) {
+		kunit_put_resource(existing);
+		return -EEXIST;
+	}
+
+	res->name = name;
+	res->should_kfree = false;
+
+	return __kunit_add_resource(test, init, free, res, data);
+}
+
+/**
+ * kunit_alloc_and_get_resource() - Allocates and returns a *test managed resource*.
+ * @test: The test context object.
+ * @init: a user supplied function to initialize the resource.
+ * @free: a user supplied function to free the resource (if needed).
+ * @internal_gfp: gfp to use for internal allocations, if unsure, use GFP_KERNEL
+ * @context: for the user to pass in arbitrary data to the init function.
+ *
+ * Allocates a *test managed resource*, a resource which will automatically be
+ * cleaned up at the end of a test case. See &struct kunit_resource for an
+ * example.
+ *
+ * This is effectively identical to kunit_alloc_resource, but returns the
+ * struct kunit_resource pointer, not just the 'data' pointer. It therefore
+ * also increments the resource's refcount, so kunit_put_resource() should be
+ * called when you've finished with it.
+ *
+ * Note: KUnit needs to allocate memory for a kunit_resource object. You must
+ * specify an @internal_gfp that is compatible with the use context of your
+ * resource.
+ */
+static inline struct kunit_resource *
+kunit_alloc_and_get_resource(struct kunit *test,
+			     kunit_resource_init_t init,
+			     kunit_resource_free_t free,
+			     gfp_t internal_gfp,
+			     void *context)
+{
+	struct kunit_resource *res;
+	int ret;
+
+	res = kzalloc(sizeof(*res), internal_gfp);
+	if (!res)
+		return NULL;
+
+	res->should_kfree = true;
+
+	ret = __kunit_add_resource(test, init, free, res, context);
+	if (!ret) {
+		/*
+		 * bump refcount for get; kunit_resource_put() should be called
+		 * when done.
+		 */
+		kunit_get_resource(res);
+		return res;
+	}
+	return NULL;
+}
+
+/**
+ * kunit_alloc_resource() - Allocates a *test managed resource*.
+ * @test: The test context object.
+ * @init: a user supplied function to initialize the resource.
+ * @free: a user supplied function to free the resource (if needed).
+ * @internal_gfp: gfp to use for internal allocations, if unsure, use GFP_KERNEL
+ * @context: for the user to pass in arbitrary data to the init function.
+ *
+ * Allocates a *test managed resource*, a resource which will automatically be
+ * cleaned up at the end of a test case. See &struct kunit_resource for an
+ * example.
+ *
+ * Note: KUnit needs to allocate memory for a kunit_resource object. You must
+ * specify an @internal_gfp that is compatible with the use context of your
+ * resource.
+ */
+static inline void *kunit_alloc_resource(struct kunit *test,
+					 kunit_resource_init_t init,
+					 kunit_resource_free_t free,
+					 gfp_t internal_gfp,
+					 void *context)
+{
+	struct kunit_resource *res;
+
+	res = kzalloc(sizeof(*res), internal_gfp);
+	if (!res)
+		return NULL;
+
+	res->should_kfree = true;
+	if (!__kunit_add_resource(test, init, free, res, context))
+		return res->data;
+
+	return NULL;
+}
+
+typedef bool (*kunit_resource_match_t)(struct kunit *test,
+				       struct kunit_resource *res,
+				       void *match_data);
+
+/**
+ * kunit_resource_name_match() - Match a resource with the same name.
+ * @test: Test case to which the resource belongs.
+ * @res: The resource.
+ * @match_name: The name to match against.
+ */
+static inline bool kunit_resource_name_match(struct kunit *test,
+					     struct kunit_resource *res,
+					     void *match_name)
+{
+	return res->name && strcmp(res->name, match_name) == 0;
+}
+
+/**
+ * kunit_find_resource() - Find a resource using match function/data.
+ * @test: Test case to which the resource belongs.
+ * @match: match function to be applied to resources/match data.
+ * @match_data: data to be used in matching.
+ */
+static inline struct kunit_resource *
+kunit_find_resource(struct kunit *test,
+		    kunit_resource_match_t match,
+		    void *match_data)
+{
+	struct kunit_resource *res, *found = NULL;
+	unsigned long flags;
+
+	spin_lock_irqsave(&test->lock, flags);
+
+	list_for_each_entry_reverse(res, &test->resources, node) {
+		if (match(test, res, (void *)match_data)) {
+			found = res;
+			kunit_get_resource(found);
+			break;
+		}
+	}
+
+	spin_unlock_irqrestore(&test->lock, flags);
+
+	return found;
+}
+
+/**
+ * kunit_find_named_resource() - Find a resource using match name.
+ * @test: Test case to which the resource belongs.
+ * @name: match name.
+ */
+static inline struct kunit_resource *
+kunit_find_named_resource(struct kunit *test,
+			  const char *name)
+{
+	return kunit_find_resource(test, kunit_resource_name_match,
+				   (void *)name);
+}
+
+/**
+ * kunit_destroy_resource() - Find a kunit_resource and destroy it.
+ * @test: Test case to which the resource belongs.
+ * @match: Match function. Returns whether a given resource matches @match_data.
+ * @match_data: Data passed into @match.
+ *
+ * RETURNS:
+ * 0 if kunit_resource is found and freed, -ENOENT if not found.
+ */
+int kunit_destroy_resource(struct kunit *test,
+			   kunit_resource_match_t match,
+			   void *match_data);
+
+static inline int kunit_destroy_named_resource(struct kunit *test,
+					       const char *name)
+{
+	return kunit_destroy_resource(test, kunit_resource_name_match,
+				      (void *)name);
+}
+
+/**
+ * kunit_remove_resource() - remove resource from resource list associated with
+ *			     test.
+ * @test: The test context object.
+ * @res: The resource to be removed.
+ *
+ * Note that the resource will not be immediately freed since it is likely
+ * the caller has a reference to it via alloc_and_get() or find();
+ * in this case a final call to kunit_put_resource() is required.
+ */
+void kunit_remove_resource(struct kunit *test, struct kunit_resource *res);
+
+#endif /* _KUNIT_RESOURCE_H */