1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4 */
5#include <linux/memremap.h>
6#include <linux/rculist.h>
7#include <linux/export.h>
8#include <linux/ioport.h>
9#include <linux/module.h>
10#include <linux/types.h>
11#include <linux/pfn_t.h>
12#include <linux/acpi.h>
13#include <linux/io.h>
14#include <linux/mm.h>
15#include "nfit_test.h"
16
17static LIST_HEAD(iomap_head);
18
19static struct iomap_ops {
20	nfit_test_lookup_fn nfit_test_lookup;
21	nfit_test_evaluate_dsm_fn evaluate_dsm;
22	struct list_head list;
23} iomap_ops = {
24	.list = LIST_HEAD_INIT(iomap_ops.list),
25};
26
27void nfit_test_setup(nfit_test_lookup_fn lookup,
28		nfit_test_evaluate_dsm_fn evaluate)
29{
30	iomap_ops.nfit_test_lookup = lookup;
31	iomap_ops.evaluate_dsm = evaluate;
32	list_add_rcu(&iomap_ops.list, &iomap_head);
33}
34EXPORT_SYMBOL(nfit_test_setup);
35
36void nfit_test_teardown(void)
37{
38	list_del_rcu(&iomap_ops.list);
39	synchronize_rcu();
40}
41EXPORT_SYMBOL(nfit_test_teardown);
42
43static struct nfit_test_resource *__get_nfit_res(resource_size_t resource)
44{
45	struct iomap_ops *ops;
46
47	ops = list_first_or_null_rcu(&iomap_head, typeof(*ops), list);
48	if (ops)
49		return ops->nfit_test_lookup(resource);
50	return NULL;
51}
52
53struct nfit_test_resource *get_nfit_res(resource_size_t resource)
54{
55	struct nfit_test_resource *res;
56
57	rcu_read_lock();
58	res = __get_nfit_res(resource);
59	rcu_read_unlock();
60
61	return res;
62}
63EXPORT_SYMBOL(get_nfit_res);
64
65#define __nfit_test_ioremap(offset, size, fallback_fn) ({		\
66	struct nfit_test_resource *nfit_res = get_nfit_res(offset);	\
67	nfit_res ?							\
68		(void __iomem *) nfit_res->buf + (offset)		\
69			- nfit_res->res.start				\
70	:								\
71		fallback_fn((offset), (size)) ;				\
72})
73
74void __iomem *__wrap_devm_ioremap(struct device *dev,
75		resource_size_t offset, unsigned long size)
76{
77	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
78
79	if (nfit_res)
80		return (void __iomem *) nfit_res->buf + offset
81			- nfit_res->res.start;
82	return devm_ioremap(dev, offset, size);
83}
84EXPORT_SYMBOL(__wrap_devm_ioremap);
85
86void *__wrap_devm_memremap(struct device *dev, resource_size_t offset,
87		size_t size, unsigned long flags)
88{
89	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
90
91	if (nfit_res)
92		return nfit_res->buf + offset - nfit_res->res.start;
93	return devm_memremap(dev, offset, size, flags);
94}
95EXPORT_SYMBOL(__wrap_devm_memremap);
96
97static void nfit_test_kill(void *_pgmap)
98{
99	struct dev_pagemap *pgmap = _pgmap;
100
101	WARN_ON(!pgmap);
102
103	percpu_ref_kill(&pgmap->ref);
104
105	wait_for_completion(&pgmap->done);
106	percpu_ref_exit(&pgmap->ref);
107}
108
109static void dev_pagemap_percpu_release(struct percpu_ref *ref)
110{
111	struct dev_pagemap *pgmap = container_of(ref, struct dev_pagemap, ref);
112
113	complete(&pgmap->done);
114}
115
116void *__wrap_devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
117{
118	int error;
119	resource_size_t offset = pgmap->range.start;
120	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
121
122	if (!nfit_res)
123		return devm_memremap_pages(dev, pgmap);
124
125	init_completion(&pgmap->done);
126	error = percpu_ref_init(&pgmap->ref, dev_pagemap_percpu_release, 0,
127				GFP_KERNEL);
128	if (error)
129		return ERR_PTR(error);
130
131	error = devm_add_action_or_reset(dev, nfit_test_kill, pgmap);
132	if (error)
133		return ERR_PTR(error);
134	return nfit_res->buf + offset - nfit_res->res.start;
135}
136EXPORT_SYMBOL_GPL(__wrap_devm_memremap_pages);
137
138pfn_t __wrap_phys_to_pfn_t(phys_addr_t addr, unsigned long flags)
139{
140	struct nfit_test_resource *nfit_res = get_nfit_res(addr);
141
142	if (nfit_res)
143		flags &= ~PFN_MAP;
144        return phys_to_pfn_t(addr, flags);
145}
146EXPORT_SYMBOL(__wrap_phys_to_pfn_t);
147
148void *__wrap_memremap(resource_size_t offset, size_t size,
149		unsigned long flags)
150{
151	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
152
153	if (nfit_res)
154		return nfit_res->buf + offset - nfit_res->res.start;
155	return memremap(offset, size, flags);
156}
157EXPORT_SYMBOL(__wrap_memremap);
158
159void __wrap_devm_memunmap(struct device *dev, void *addr)
160{
161	struct nfit_test_resource *nfit_res = get_nfit_res((long) addr);
162
163	if (nfit_res)
164		return;
165	return devm_memunmap(dev, addr);
166}
167EXPORT_SYMBOL(__wrap_devm_memunmap);
168
169void __iomem *__wrap_ioremap(resource_size_t offset, unsigned long size)
170{
171	return __nfit_test_ioremap(offset, size, ioremap);
172}
173EXPORT_SYMBOL(__wrap_ioremap);
174
175void __iomem *__wrap_ioremap_wc(resource_size_t offset, unsigned long size)
176{
177	return __nfit_test_ioremap(offset, size, ioremap_wc);
178}
179EXPORT_SYMBOL(__wrap_ioremap_wc);
180
181void __wrap_iounmap(volatile void __iomem *addr)
182{
183	struct nfit_test_resource *nfit_res = get_nfit_res((long) addr);
184	if (nfit_res)
185		return;
186	return iounmap(addr);
187}
188EXPORT_SYMBOL(__wrap_iounmap);
189
190void __wrap_memunmap(void *addr)
191{
192	struct nfit_test_resource *nfit_res = get_nfit_res((long) addr);
193
194	if (nfit_res)
195		return;
196	return memunmap(addr);
197}
198EXPORT_SYMBOL(__wrap_memunmap);
199
200static bool nfit_test_release_region(struct device *dev,
201		struct resource *parent, resource_size_t start,
202		resource_size_t n);
203
204static void nfit_devres_release(struct device *dev, void *data)
205{
206	struct resource *res = *((struct resource **) data);
207
208	WARN_ON(!nfit_test_release_region(NULL, &iomem_resource, res->start,
209			resource_size(res)));
210}
211
212static int match(struct device *dev, void *__res, void *match_data)
213{
214	struct resource *res = *((struct resource **) __res);
215	resource_size_t start = *((resource_size_t *) match_data);
216
217	return res->start == start;
218}
219
220static bool nfit_test_release_region(struct device *dev,
221		struct resource *parent, resource_size_t start,
222		resource_size_t n)
223{
224	if (parent == &iomem_resource) {
225		struct nfit_test_resource *nfit_res = get_nfit_res(start);
226
227		if (nfit_res) {
228			struct nfit_test_request *req;
229			struct resource *res = NULL;
230
231			if (dev) {
232				devres_release(dev, nfit_devres_release, match,
233						&start);
234				return true;
235			}
236
237			spin_lock(&nfit_res->lock);
238			list_for_each_entry(req, &nfit_res->requests, list)
239				if (req->res.start == start) {
240					res = &req->res;
241					list_del(&req->list);
242					break;
243				}
244			spin_unlock(&nfit_res->lock);
245
246			WARN(!res || resource_size(res) != n,
247					"%s: start: %llx n: %llx mismatch: %pr\n",
248						__func__, start, n, res);
249			if (res)
250				kfree(req);
251			return true;
252		}
253	}
254	return false;
255}
256
257static struct resource *nfit_test_request_region(struct device *dev,
258		struct resource *parent, resource_size_t start,
259		resource_size_t n, const char *name, int flags)
260{
261	struct nfit_test_resource *nfit_res;
262
263	if (parent == &iomem_resource) {
264		nfit_res = get_nfit_res(start);
265		if (nfit_res) {
266			struct nfit_test_request *req;
267			struct resource *res = NULL;
268
269			if (start + n > nfit_res->res.start
270					+ resource_size(&nfit_res->res)) {
271				pr_debug("%s: start: %llx n: %llx overflow: %pr\n",
272						__func__, start, n,
273						&nfit_res->res);
274				return NULL;
275			}
276
277			spin_lock(&nfit_res->lock);
278			list_for_each_entry(req, &nfit_res->requests, list)
279				if (start == req->res.start) {
280					res = &req->res;
281					break;
282				}
283			spin_unlock(&nfit_res->lock);
284
285			if (res) {
286				WARN(1, "%pr already busy\n", res);
287				return NULL;
288			}
289
290			req = kzalloc(sizeof(*req), GFP_KERNEL);
291			if (!req)
292				return NULL;
293			INIT_LIST_HEAD(&req->list);
294			res = &req->res;
295
296			res->start = start;
297			res->end = start + n - 1;
298			res->name = name;
299			res->flags = resource_type(parent);
300			res->flags |= IORESOURCE_BUSY | flags;
301			spin_lock(&nfit_res->lock);
302			list_add(&req->list, &nfit_res->requests);
303			spin_unlock(&nfit_res->lock);
304
305			if (dev) {
306				struct resource **d;
307
308				d = devres_alloc(nfit_devres_release,
309						sizeof(struct resource *),
310						GFP_KERNEL);
311				if (!d)
312					return NULL;
313				*d = res;
314				devres_add(dev, d);
315			}
316
317			pr_debug("%s: %pr\n", __func__, res);
318			return res;
319		}
320	}
321	if (dev)
322		return __devm_request_region(dev, parent, start, n, name);
323	return __request_region(parent, start, n, name, flags);
324}
325
326struct resource *__wrap___request_region(struct resource *parent,
327		resource_size_t start, resource_size_t n, const char *name,
328		int flags)
329{
330	return nfit_test_request_region(NULL, parent, start, n, name, flags);
331}
332EXPORT_SYMBOL(__wrap___request_region);
333
334int __wrap_insert_resource(struct resource *parent, struct resource *res)
335{
336	if (get_nfit_res(res->start))
337		return 0;
338	return insert_resource(parent, res);
339}
340EXPORT_SYMBOL(__wrap_insert_resource);
341
342int __wrap_remove_resource(struct resource *res)
343{
344	if (get_nfit_res(res->start))
345		return 0;
346	return remove_resource(res);
347}
348EXPORT_SYMBOL(__wrap_remove_resource);
349
350struct resource *__wrap___devm_request_region(struct device *dev,
351		struct resource *parent, resource_size_t start,
352		resource_size_t n, const char *name)
353{
354	if (!dev)
355		return NULL;
356	return nfit_test_request_region(dev, parent, start, n, name, 0);
357}
358EXPORT_SYMBOL(__wrap___devm_request_region);
359
360void __wrap___release_region(struct resource *parent, resource_size_t start,
361		resource_size_t n)
362{
363	if (!nfit_test_release_region(NULL, parent, start, n))
364		__release_region(parent, start, n);
365}
366EXPORT_SYMBOL(__wrap___release_region);
367
368void __wrap___devm_release_region(struct device *dev, struct resource *parent,
369		resource_size_t start, resource_size_t n)
370{
371	if (!nfit_test_release_region(dev, parent, start, n))
372		__devm_release_region(dev, parent, start, n);
373}
374EXPORT_SYMBOL(__wrap___devm_release_region);
375
376acpi_status __wrap_acpi_evaluate_object(acpi_handle handle, acpi_string path,
377		struct acpi_object_list *p, struct acpi_buffer *buf)
378{
379	struct nfit_test_resource *nfit_res = get_nfit_res((long) handle);
380	union acpi_object **obj;
381
382	if (!nfit_res || strcmp(path, "_FIT") || !buf)
383		return acpi_evaluate_object(handle, path, p, buf);
384
385	obj = nfit_res->buf;
386	buf->length = sizeof(union acpi_object);
387	buf->pointer = *obj;
388	return AE_OK;
389}
390EXPORT_SYMBOL(__wrap_acpi_evaluate_object);
391
392union acpi_object * __wrap_acpi_evaluate_dsm(acpi_handle handle, const guid_t *guid,
393		u64 rev, u64 func, union acpi_object *argv4)
394{
395	union acpi_object *obj = ERR_PTR(-ENXIO);
396	struct iomap_ops *ops;
397
398	rcu_read_lock();
399	ops = list_first_or_null_rcu(&iomap_head, typeof(*ops), list);
400	if (ops)
401		obj = ops->evaluate_dsm(handle, guid, rev, func, argv4);
402	rcu_read_unlock();
403
404	if (IS_ERR(obj))
405		return acpi_evaluate_dsm(handle, guid, rev, func, argv4);
406	return obj;
407}
408EXPORT_SYMBOL(__wrap_acpi_evaluate_dsm);
409
410MODULE_LICENSE("GPL v2");
411