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 
17 static LIST_HEAD(iomap_head);
18 
19 static 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 
nfit_test_setup(nfit_test_lookup_fn lookup,nfit_test_evaluate_dsm_fn evaluate)27 void 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 }
34 EXPORT_SYMBOL(nfit_test_setup);
35 
nfit_test_teardown(void)36 void nfit_test_teardown(void)
37 {
38 	list_del_rcu(&iomap_ops.list);
39 	synchronize_rcu();
40 }
41 EXPORT_SYMBOL(nfit_test_teardown);
42 
__get_nfit_res(resource_size_t resource)43 static 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 
get_nfit_res(resource_size_t resource)53 struct 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 }
63 EXPORT_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 
__wrap_devm_ioremap(struct device * dev,resource_size_t offset,unsigned long size)74 void __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 }
84 EXPORT_SYMBOL(__wrap_devm_ioremap);
85 
__wrap_devm_memremap(struct device * dev,resource_size_t offset,size_t size,unsigned long flags)86 void *__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 }
95 EXPORT_SYMBOL(__wrap_devm_memremap);
96 
nfit_test_kill(void * _pgmap)97 static 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 
dev_pagemap_percpu_release(struct percpu_ref * ref)109 static 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 
__wrap_devm_memremap_pages(struct device * dev,struct dev_pagemap * pgmap)116 void *__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 }
136 EXPORT_SYMBOL_GPL(__wrap_devm_memremap_pages);
137 
__wrap_phys_to_pfn_t(phys_addr_t addr,unsigned long flags)138 pfn_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 }
146 EXPORT_SYMBOL(__wrap_phys_to_pfn_t);
147 
__wrap_memremap(resource_size_t offset,size_t size,unsigned long flags)148 void *__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 }
157 EXPORT_SYMBOL(__wrap_memremap);
158 
__wrap_devm_memunmap(struct device * dev,void * addr)159 void __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 }
167 EXPORT_SYMBOL(__wrap_devm_memunmap);
168 
__wrap_ioremap(resource_size_t offset,unsigned long size)169 void __iomem *__wrap_ioremap(resource_size_t offset, unsigned long size)
170 {
171 	return __nfit_test_ioremap(offset, size, ioremap);
172 }
173 EXPORT_SYMBOL(__wrap_ioremap);
174 
__wrap_ioremap_wc(resource_size_t offset,unsigned long size)175 void __iomem *__wrap_ioremap_wc(resource_size_t offset, unsigned long size)
176 {
177 	return __nfit_test_ioremap(offset, size, ioremap_wc);
178 }
179 EXPORT_SYMBOL(__wrap_ioremap_wc);
180 
__wrap_iounmap(volatile void __iomem * addr)181 void __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 }
188 EXPORT_SYMBOL(__wrap_iounmap);
189 
__wrap_memunmap(void * addr)190 void __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 }
198 EXPORT_SYMBOL(__wrap_memunmap);
199 
200 static bool nfit_test_release_region(struct device *dev,
201 		struct resource *parent, resource_size_t start,
202 		resource_size_t n);
203 
nfit_devres_release(struct device * dev,void * data)204 static 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 
match(struct device * dev,void * __res,void * match_data)212 static 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 
nfit_test_release_region(struct device * dev,struct resource * parent,resource_size_t start,resource_size_t n)220 static 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 
nfit_test_request_region(struct device * dev,struct resource * parent,resource_size_t start,resource_size_t n,const char * name,int flags)257 static 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 
__wrap___request_region(struct resource * parent,resource_size_t start,resource_size_t n,const char * name,int flags)326 struct 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 }
332 EXPORT_SYMBOL(__wrap___request_region);
333 
__wrap_insert_resource(struct resource * parent,struct resource * res)334 int __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 }
340 EXPORT_SYMBOL(__wrap_insert_resource);
341 
__wrap_remove_resource(struct resource * res)342 int __wrap_remove_resource(struct resource *res)
343 {
344 	if (get_nfit_res(res->start))
345 		return 0;
346 	return remove_resource(res);
347 }
348 EXPORT_SYMBOL(__wrap_remove_resource);
349 
__wrap___devm_request_region(struct device * dev,struct resource * parent,resource_size_t start,resource_size_t n,const char * name)350 struct 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 }
358 EXPORT_SYMBOL(__wrap___devm_request_region);
359 
__wrap___release_region(struct resource * parent,resource_size_t start,resource_size_t n)360 void __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 }
366 EXPORT_SYMBOL(__wrap___release_region);
367 
__wrap___devm_release_region(struct device * dev,struct resource * parent,resource_size_t start,resource_size_t n)368 void __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 }
374 EXPORT_SYMBOL(__wrap___devm_release_region);
375 
__wrap_acpi_evaluate_object(acpi_handle handle,acpi_string path,struct acpi_object_list * p,struct acpi_buffer * buf)376 acpi_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 }
390 EXPORT_SYMBOL(__wrap_acpi_evaluate_object);
391 
__wrap_acpi_evaluate_dsm(acpi_handle handle,const guid_t * guid,u64 rev,u64 func,union acpi_object * argv4)392 union 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 }
408 EXPORT_SYMBOL(__wrap_acpi_evaluate_dsm);
409 
410 MODULE_LICENSE("GPL v2");
411