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
65void __iomem *__nfit_test_ioremap(resource_size_t offset, unsigned long size,
66		void __iomem *(*fallback_fn)(resource_size_t, unsigned long))
67{
68	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
69
70	if (nfit_res)
71		return (void __iomem *) nfit_res->buf + offset
72			- nfit_res->res.start;
73	return fallback_fn(offset, size);
74}
75
76void __iomem *__wrap_devm_ioremap(struct device *dev,
77		resource_size_t offset, unsigned long size)
78{
79	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
80
81	if (nfit_res)
82		return (void __iomem *) nfit_res->buf + offset
83			- nfit_res->res.start;
84	return devm_ioremap(dev, offset, size);
85}
86EXPORT_SYMBOL(__wrap_devm_ioremap);
87
88void *__wrap_devm_memremap(struct device *dev, resource_size_t offset,
89		size_t size, unsigned long flags)
90{
91	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
92
93	if (nfit_res)
94		return nfit_res->buf + offset - nfit_res->res.start;
95	return devm_memremap(dev, offset, size, flags);
96}
97EXPORT_SYMBOL(__wrap_devm_memremap);
98
99static void nfit_test_kill(void *_pgmap)
100{
101	struct dev_pagemap *pgmap = _pgmap;
102
103	WARN_ON(!pgmap || !pgmap->ref);
104
105	if (pgmap->ops && pgmap->ops->kill)
106		pgmap->ops->kill(pgmap);
107	else
108		percpu_ref_kill(pgmap->ref);
109
110	if (pgmap->ops && pgmap->ops->cleanup) {
111		pgmap->ops->cleanup(pgmap);
112	} else {
113		wait_for_completion(&pgmap->done);
114		percpu_ref_exit(pgmap->ref);
115	}
116}
117
118static void dev_pagemap_percpu_release(struct percpu_ref *ref)
119{
120	struct dev_pagemap *pgmap =
121		container_of(ref, struct dev_pagemap, internal_ref);
122
123	complete(&pgmap->done);
124}
125
126void *__wrap_devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
127{
128	int error;
129	resource_size_t offset = pgmap->range.start;
130	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
131
132	if (!nfit_res)
133		return devm_memremap_pages(dev, pgmap);
134
135	if (!pgmap->ref) {
136		if (pgmap->ops && (pgmap->ops->kill || pgmap->ops->cleanup))
137			return ERR_PTR(-EINVAL);
138
139		init_completion(&pgmap->done);
140		error = percpu_ref_init(&pgmap->internal_ref,
141				dev_pagemap_percpu_release, 0, GFP_KERNEL);
142		if (error)
143			return ERR_PTR(error);
144		pgmap->ref = &pgmap->internal_ref;
145	} else {
146		if (!pgmap->ops || !pgmap->ops->kill || !pgmap->ops->cleanup) {
147			WARN(1, "Missing reference count teardown definition\n");
148			return ERR_PTR(-EINVAL);
149		}
150	}
151
152	error = devm_add_action_or_reset(dev, nfit_test_kill, pgmap);
153	if (error)
154		return ERR_PTR(error);
155	return nfit_res->buf + offset - nfit_res->res.start;
156}
157EXPORT_SYMBOL_GPL(__wrap_devm_memremap_pages);
158
159pfn_t __wrap_phys_to_pfn_t(phys_addr_t addr, unsigned long flags)
160{
161	struct nfit_test_resource *nfit_res = get_nfit_res(addr);
162
163	if (nfit_res)
164		flags &= ~PFN_MAP;
165        return phys_to_pfn_t(addr, flags);
166}
167EXPORT_SYMBOL(__wrap_phys_to_pfn_t);
168
169void *__wrap_memremap(resource_size_t offset, size_t size,
170		unsigned long flags)
171{
172	struct nfit_test_resource *nfit_res = get_nfit_res(offset);
173
174	if (nfit_res)
175		return nfit_res->buf + offset - nfit_res->res.start;
176	return memremap(offset, size, flags);
177}
178EXPORT_SYMBOL(__wrap_memremap);
179
180void __wrap_devm_memunmap(struct device *dev, void *addr)
181{
182	struct nfit_test_resource *nfit_res = get_nfit_res((long) addr);
183
184	if (nfit_res)
185		return;
186	return devm_memunmap(dev, addr);
187}
188EXPORT_SYMBOL(__wrap_devm_memunmap);
189
190void __iomem *__wrap_ioremap(resource_size_t offset, unsigned long size)
191{
192	return __nfit_test_ioremap(offset, size, ioremap);
193}
194EXPORT_SYMBOL(__wrap_ioremap);
195
196void __iomem *__wrap_ioremap_wc(resource_size_t offset, unsigned long size)
197{
198	return __nfit_test_ioremap(offset, size, ioremap_wc);
199}
200EXPORT_SYMBOL(__wrap_ioremap_wc);
201
202void __wrap_iounmap(volatile void __iomem *addr)
203{
204	struct nfit_test_resource *nfit_res = get_nfit_res((long) addr);
205	if (nfit_res)
206		return;
207	return iounmap(addr);
208}
209EXPORT_SYMBOL(__wrap_iounmap);
210
211void __wrap_memunmap(void *addr)
212{
213	struct nfit_test_resource *nfit_res = get_nfit_res((long) addr);
214
215	if (nfit_res)
216		return;
217	return memunmap(addr);
218}
219EXPORT_SYMBOL(__wrap_memunmap);
220
221static bool nfit_test_release_region(struct device *dev,
222		struct resource *parent, resource_size_t start,
223		resource_size_t n);
224
225static void nfit_devres_release(struct device *dev, void *data)
226{
227	struct resource *res = *((struct resource **) data);
228
229	WARN_ON(!nfit_test_release_region(NULL, &iomem_resource, res->start,
230			resource_size(res)));
231}
232
233static int match(struct device *dev, void *__res, void *match_data)
234{
235	struct resource *res = *((struct resource **) __res);
236	resource_size_t start = *((resource_size_t *) match_data);
237
238	return res->start == start;
239}
240
241static bool nfit_test_release_region(struct device *dev,
242		struct resource *parent, resource_size_t start,
243		resource_size_t n)
244{
245	if (parent == &iomem_resource) {
246		struct nfit_test_resource *nfit_res = get_nfit_res(start);
247
248		if (nfit_res) {
249			struct nfit_test_request *req;
250			struct resource *res = NULL;
251
252			if (dev) {
253				devres_release(dev, nfit_devres_release, match,
254						&start);
255				return true;
256			}
257
258			spin_lock(&nfit_res->lock);
259			list_for_each_entry(req, &nfit_res->requests, list)
260				if (req->res.start == start) {
261					res = &req->res;
262					list_del(&req->list);
263					break;
264				}
265			spin_unlock(&nfit_res->lock);
266
267			WARN(!res || resource_size(res) != n,
268					"%s: start: %llx n: %llx mismatch: %pr\n",
269						__func__, start, n, res);
270			if (res)
271				kfree(req);
272			return true;
273		}
274	}
275	return false;
276}
277
278static struct resource *nfit_test_request_region(struct device *dev,
279		struct resource *parent, resource_size_t start,
280		resource_size_t n, const char *name, int flags)
281{
282	struct nfit_test_resource *nfit_res;
283
284	if (parent == &iomem_resource) {
285		nfit_res = get_nfit_res(start);
286		if (nfit_res) {
287			struct nfit_test_request *req;
288			struct resource *res = NULL;
289
290			if (start + n > nfit_res->res.start
291					+ resource_size(&nfit_res->res)) {
292				pr_debug("%s: start: %llx n: %llx overflow: %pr\n",
293						__func__, start, n,
294						&nfit_res->res);
295				return NULL;
296			}
297
298			spin_lock(&nfit_res->lock);
299			list_for_each_entry(req, &nfit_res->requests, list)
300				if (start == req->res.start) {
301					res = &req->res;
302					break;
303				}
304			spin_unlock(&nfit_res->lock);
305
306			if (res) {
307				WARN(1, "%pr already busy\n", res);
308				return NULL;
309			}
310
311			req = kzalloc(sizeof(*req), GFP_KERNEL);
312			if (!req)
313				return NULL;
314			INIT_LIST_HEAD(&req->list);
315			res = &req->res;
316
317			res->start = start;
318			res->end = start + n - 1;
319			res->name = name;
320			res->flags = resource_type(parent);
321			res->flags |= IORESOURCE_BUSY | flags;
322			spin_lock(&nfit_res->lock);
323			list_add(&req->list, &nfit_res->requests);
324			spin_unlock(&nfit_res->lock);
325
326			if (dev) {
327				struct resource **d;
328
329				d = devres_alloc(nfit_devres_release,
330						sizeof(struct resource *),
331						GFP_KERNEL);
332				if (!d)
333					return NULL;
334				*d = res;
335				devres_add(dev, d);
336			}
337
338			pr_debug("%s: %pr\n", __func__, res);
339			return res;
340		}
341	}
342	if (dev)
343		return __devm_request_region(dev, parent, start, n, name);
344	return __request_region(parent, start, n, name, flags);
345}
346
347struct resource *__wrap___request_region(struct resource *parent,
348		resource_size_t start, resource_size_t n, const char *name,
349		int flags)
350{
351	return nfit_test_request_region(NULL, parent, start, n, name, flags);
352}
353EXPORT_SYMBOL(__wrap___request_region);
354
355int __wrap_insert_resource(struct resource *parent, struct resource *res)
356{
357	if (get_nfit_res(res->start))
358		return 0;
359	return insert_resource(parent, res);
360}
361EXPORT_SYMBOL(__wrap_insert_resource);
362
363int __wrap_remove_resource(struct resource *res)
364{
365	if (get_nfit_res(res->start))
366		return 0;
367	return remove_resource(res);
368}
369EXPORT_SYMBOL(__wrap_remove_resource);
370
371struct resource *__wrap___devm_request_region(struct device *dev,
372		struct resource *parent, resource_size_t start,
373		resource_size_t n, const char *name)
374{
375	if (!dev)
376		return NULL;
377	return nfit_test_request_region(dev, parent, start, n, name, 0);
378}
379EXPORT_SYMBOL(__wrap___devm_request_region);
380
381void __wrap___release_region(struct resource *parent, resource_size_t start,
382		resource_size_t n)
383{
384	if (!nfit_test_release_region(NULL, parent, start, n))
385		__release_region(parent, start, n);
386}
387EXPORT_SYMBOL(__wrap___release_region);
388
389void __wrap___devm_release_region(struct device *dev, struct resource *parent,
390		resource_size_t start, resource_size_t n)
391{
392	if (!nfit_test_release_region(dev, parent, start, n))
393		__devm_release_region(dev, parent, start, n);
394}
395EXPORT_SYMBOL(__wrap___devm_release_region);
396
397acpi_status __wrap_acpi_evaluate_object(acpi_handle handle, acpi_string path,
398		struct acpi_object_list *p, struct acpi_buffer *buf)
399{
400	struct nfit_test_resource *nfit_res = get_nfit_res((long) handle);
401	union acpi_object **obj;
402
403	if (!nfit_res || strcmp(path, "_FIT") || !buf)
404		return acpi_evaluate_object(handle, path, p, buf);
405
406	obj = nfit_res->buf;
407	buf->length = sizeof(union acpi_object);
408	buf->pointer = *obj;
409	return AE_OK;
410}
411EXPORT_SYMBOL(__wrap_acpi_evaluate_object);
412
413union acpi_object * __wrap_acpi_evaluate_dsm(acpi_handle handle, const guid_t *guid,
414		u64 rev, u64 func, union acpi_object *argv4)
415{
416	union acpi_object *obj = ERR_PTR(-ENXIO);
417	struct iomap_ops *ops;
418
419	rcu_read_lock();
420	ops = list_first_or_null_rcu(&iomap_head, typeof(*ops), list);
421	if (ops)
422		obj = ops->evaluate_dsm(handle, guid, rev, func, argv4);
423	rcu_read_unlock();
424
425	if (IS_ERR(obj))
426		return acpi_evaluate_dsm(handle, guid, rev, func, argv4);
427	return obj;
428}
429EXPORT_SYMBOL(__wrap_acpi_evaluate_dsm);
430
431MODULE_LICENSE("GPL v2");
432