xref: /openbmc/linux/drivers/nvdimm/core.c (revision e6e8c82b)
1 /*
2  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  */
13 #include <linux/libnvdimm.h>
14 #include <linux/badblocks.h>
15 #include <linux/export.h>
16 #include <linux/module.h>
17 #include <linux/blkdev.h>
18 #include <linux/device.h>
19 #include <linux/ctype.h>
20 #include <linux/ndctl.h>
21 #include <linux/mutex.h>
22 #include <linux/slab.h>
23 #include <linux/io.h>
24 #include "nd-core.h"
25 #include "nd.h"
26 
27 LIST_HEAD(nvdimm_bus_list);
28 DEFINE_MUTEX(nvdimm_bus_list_mutex);
29 
30 void nvdimm_bus_lock(struct device *dev)
31 {
32 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
33 
34 	if (!nvdimm_bus)
35 		return;
36 	mutex_lock(&nvdimm_bus->reconfig_mutex);
37 }
38 EXPORT_SYMBOL(nvdimm_bus_lock);
39 
40 void nvdimm_bus_unlock(struct device *dev)
41 {
42 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
43 
44 	if (!nvdimm_bus)
45 		return;
46 	mutex_unlock(&nvdimm_bus->reconfig_mutex);
47 }
48 EXPORT_SYMBOL(nvdimm_bus_unlock);
49 
50 bool is_nvdimm_bus_locked(struct device *dev)
51 {
52 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
53 
54 	if (!nvdimm_bus)
55 		return false;
56 	return mutex_is_locked(&nvdimm_bus->reconfig_mutex);
57 }
58 EXPORT_SYMBOL(is_nvdimm_bus_locked);
59 
60 struct nvdimm_map {
61 	struct nvdimm_bus *nvdimm_bus;
62 	struct list_head list;
63 	resource_size_t offset;
64 	unsigned long flags;
65 	size_t size;
66 	union {
67 		void *mem;
68 		void __iomem *iomem;
69 	};
70 	struct kref kref;
71 };
72 
73 static struct nvdimm_map *find_nvdimm_map(struct device *dev,
74 		resource_size_t offset)
75 {
76 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
77 	struct nvdimm_map *nvdimm_map;
78 
79 	list_for_each_entry(nvdimm_map, &nvdimm_bus->mapping_list, list)
80 		if (nvdimm_map->offset == offset)
81 			return nvdimm_map;
82 	return NULL;
83 }
84 
85 static struct nvdimm_map *alloc_nvdimm_map(struct device *dev,
86 		resource_size_t offset, size_t size, unsigned long flags)
87 {
88 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
89 	struct nvdimm_map *nvdimm_map;
90 
91 	nvdimm_map = kzalloc(sizeof(*nvdimm_map), GFP_KERNEL);
92 	if (!nvdimm_map)
93 		return NULL;
94 
95 	INIT_LIST_HEAD(&nvdimm_map->list);
96 	nvdimm_map->nvdimm_bus = nvdimm_bus;
97 	nvdimm_map->offset = offset;
98 	nvdimm_map->flags = flags;
99 	nvdimm_map->size = size;
100 	kref_init(&nvdimm_map->kref);
101 
102 	if (!request_mem_region(offset, size, dev_name(&nvdimm_bus->dev))) {
103 		dev_err(&nvdimm_bus->dev, "failed to request %pa + %zd for %s\n",
104 				&offset, size, dev_name(dev));
105 		goto err_request_region;
106 	}
107 
108 	if (flags)
109 		nvdimm_map->mem = memremap(offset, size, flags);
110 	else
111 		nvdimm_map->iomem = ioremap(offset, size);
112 
113 	if (!nvdimm_map->mem)
114 		goto err_map;
115 
116 	dev_WARN_ONCE(dev, !is_nvdimm_bus_locked(dev), "%s: bus unlocked!",
117 			__func__);
118 	list_add(&nvdimm_map->list, &nvdimm_bus->mapping_list);
119 
120 	return nvdimm_map;
121 
122  err_map:
123 	release_mem_region(offset, size);
124  err_request_region:
125 	kfree(nvdimm_map);
126 	return NULL;
127 }
128 
129 static void nvdimm_map_release(struct kref *kref)
130 {
131 	struct nvdimm_bus *nvdimm_bus;
132 	struct nvdimm_map *nvdimm_map;
133 
134 	nvdimm_map = container_of(kref, struct nvdimm_map, kref);
135 	nvdimm_bus = nvdimm_map->nvdimm_bus;
136 
137 	dev_dbg(&nvdimm_bus->dev, "%pa\n", &nvdimm_map->offset);
138 	list_del(&nvdimm_map->list);
139 	if (nvdimm_map->flags)
140 		memunmap(nvdimm_map->mem);
141 	else
142 		iounmap(nvdimm_map->iomem);
143 	release_mem_region(nvdimm_map->offset, nvdimm_map->size);
144 	kfree(nvdimm_map);
145 }
146 
147 static void nvdimm_map_put(void *data)
148 {
149 	struct nvdimm_map *nvdimm_map = data;
150 	struct nvdimm_bus *nvdimm_bus = nvdimm_map->nvdimm_bus;
151 
152 	nvdimm_bus_lock(&nvdimm_bus->dev);
153 	kref_put(&nvdimm_map->kref, nvdimm_map_release);
154 	nvdimm_bus_unlock(&nvdimm_bus->dev);
155 }
156 
157 /**
158  * devm_nvdimm_memremap - map a resource that is shared across regions
159  * @dev: device that will own a reference to the shared mapping
160  * @offset: physical base address of the mapping
161  * @size: mapping size
162  * @flags: memremap flags, or, if zero, perform an ioremap instead
163  */
164 void *devm_nvdimm_memremap(struct device *dev, resource_size_t offset,
165 		size_t size, unsigned long flags)
166 {
167 	struct nvdimm_map *nvdimm_map;
168 
169 	nvdimm_bus_lock(dev);
170 	nvdimm_map = find_nvdimm_map(dev, offset);
171 	if (!nvdimm_map)
172 		nvdimm_map = alloc_nvdimm_map(dev, offset, size, flags);
173 	else
174 		kref_get(&nvdimm_map->kref);
175 	nvdimm_bus_unlock(dev);
176 
177 	if (!nvdimm_map)
178 		return NULL;
179 
180 	if (devm_add_action_or_reset(dev, nvdimm_map_put, nvdimm_map))
181 		return NULL;
182 
183 	return nvdimm_map->mem;
184 }
185 EXPORT_SYMBOL_GPL(devm_nvdimm_memremap);
186 
187 u64 nd_fletcher64(void *addr, size_t len, bool le)
188 {
189 	u32 *buf = addr;
190 	u32 lo32 = 0;
191 	u64 hi32 = 0;
192 	int i;
193 
194 	for (i = 0; i < len / sizeof(u32); i++) {
195 		lo32 += le ? le32_to_cpu((__le32) buf[i]) : buf[i];
196 		hi32 += lo32;
197 	}
198 
199 	return hi32 << 32 | lo32;
200 }
201 EXPORT_SYMBOL_GPL(nd_fletcher64);
202 
203 struct nvdimm_bus_descriptor *to_nd_desc(struct nvdimm_bus *nvdimm_bus)
204 {
205 	/* struct nvdimm_bus definition is private to libnvdimm */
206 	return nvdimm_bus->nd_desc;
207 }
208 EXPORT_SYMBOL_GPL(to_nd_desc);
209 
210 struct device *to_nvdimm_bus_dev(struct nvdimm_bus *nvdimm_bus)
211 {
212 	/* struct nvdimm_bus definition is private to libnvdimm */
213 	return &nvdimm_bus->dev;
214 }
215 EXPORT_SYMBOL_GPL(to_nvdimm_bus_dev);
216 
217 static bool is_uuid_sep(char sep)
218 {
219 	if (sep == '\n' || sep == '-' || sep == ':' || sep == '\0')
220 		return true;
221 	return false;
222 }
223 
224 static int nd_uuid_parse(struct device *dev, u8 *uuid_out, const char *buf,
225 		size_t len)
226 {
227 	const char *str = buf;
228 	u8 uuid[16];
229 	int i;
230 
231 	for (i = 0; i < 16; i++) {
232 		if (!isxdigit(str[0]) || !isxdigit(str[1])) {
233 			dev_dbg(dev, "pos: %d buf[%zd]: %c buf[%zd]: %c\n",
234 					i, str - buf, str[0],
235 					str + 1 - buf, str[1]);
236 			return -EINVAL;
237 		}
238 
239 		uuid[i] = (hex_to_bin(str[0]) << 4) | hex_to_bin(str[1]);
240 		str += 2;
241 		if (is_uuid_sep(*str))
242 			str++;
243 	}
244 
245 	memcpy(uuid_out, uuid, sizeof(uuid));
246 	return 0;
247 }
248 
249 /**
250  * nd_uuid_store: common implementation for writing 'uuid' sysfs attributes
251  * @dev: container device for the uuid property
252  * @uuid_out: uuid buffer to replace
253  * @buf: raw sysfs buffer to parse
254  *
255  * Enforce that uuids can only be changed while the device is disabled
256  * (driver detached)
257  * LOCKING: expects device_lock() is held on entry
258  */
259 int nd_uuid_store(struct device *dev, u8 **uuid_out, const char *buf,
260 		size_t len)
261 {
262 	u8 uuid[16];
263 	int rc;
264 
265 	if (dev->driver)
266 		return -EBUSY;
267 
268 	rc = nd_uuid_parse(dev, uuid, buf, len);
269 	if (rc)
270 		return rc;
271 
272 	kfree(*uuid_out);
273 	*uuid_out = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
274 	if (!(*uuid_out))
275 		return -ENOMEM;
276 
277 	return 0;
278 }
279 
280 ssize_t nd_size_select_show(unsigned long current_size,
281 		const unsigned long *supported, char *buf)
282 {
283 	ssize_t len = 0;
284 	int i;
285 
286 	for (i = 0; supported[i]; i++)
287 		if (current_size == supported[i])
288 			len += sprintf(buf + len, "[%ld] ", supported[i]);
289 		else
290 			len += sprintf(buf + len, "%ld ", supported[i]);
291 	len += sprintf(buf + len, "\n");
292 	return len;
293 }
294 
295 ssize_t nd_size_select_store(struct device *dev, const char *buf,
296 		unsigned long *current_size, const unsigned long *supported)
297 {
298 	unsigned long lbasize;
299 	int rc, i;
300 
301 	if (dev->driver)
302 		return -EBUSY;
303 
304 	rc = kstrtoul(buf, 0, &lbasize);
305 	if (rc)
306 		return rc;
307 
308 	for (i = 0; supported[i]; i++)
309 		if (lbasize == supported[i])
310 			break;
311 
312 	if (supported[i]) {
313 		*current_size = lbasize;
314 		return 0;
315 	} else {
316 		return -EINVAL;
317 	}
318 }
319 
320 static ssize_t commands_show(struct device *dev,
321 		struct device_attribute *attr, char *buf)
322 {
323 	int cmd, len = 0;
324 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
325 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
326 
327 	for_each_set_bit(cmd, &nd_desc->cmd_mask, BITS_PER_LONG)
328 		len += sprintf(buf + len, "%s ", nvdimm_bus_cmd_name(cmd));
329 	len += sprintf(buf + len, "\n");
330 	return len;
331 }
332 static DEVICE_ATTR_RO(commands);
333 
334 static const char *nvdimm_bus_provider(struct nvdimm_bus *nvdimm_bus)
335 {
336 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
337 	struct device *parent = nvdimm_bus->dev.parent;
338 
339 	if (nd_desc->provider_name)
340 		return nd_desc->provider_name;
341 	else if (parent)
342 		return dev_name(parent);
343 	else
344 		return "unknown";
345 }
346 
347 static ssize_t provider_show(struct device *dev,
348 		struct device_attribute *attr, char *buf)
349 {
350 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
351 
352 	return sprintf(buf, "%s\n", nvdimm_bus_provider(nvdimm_bus));
353 }
354 static DEVICE_ATTR_RO(provider);
355 
356 static int flush_namespaces(struct device *dev, void *data)
357 {
358 	device_lock(dev);
359 	device_unlock(dev);
360 	return 0;
361 }
362 
363 static int flush_regions_dimms(struct device *dev, void *data)
364 {
365 	device_lock(dev);
366 	device_unlock(dev);
367 	device_for_each_child(dev, NULL, flush_namespaces);
368 	return 0;
369 }
370 
371 static ssize_t wait_probe_show(struct device *dev,
372 		struct device_attribute *attr, char *buf)
373 {
374 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
375 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
376 	int rc;
377 
378 	if (nd_desc->flush_probe) {
379 		rc = nd_desc->flush_probe(nd_desc);
380 		if (rc)
381 			return rc;
382 	}
383 	nd_synchronize();
384 	device_for_each_child(dev, NULL, flush_regions_dimms);
385 	return sprintf(buf, "1\n");
386 }
387 static DEVICE_ATTR_RO(wait_probe);
388 
389 static struct attribute *nvdimm_bus_attributes[] = {
390 	&dev_attr_commands.attr,
391 	&dev_attr_wait_probe.attr,
392 	&dev_attr_provider.attr,
393 	NULL,
394 };
395 
396 struct attribute_group nvdimm_bus_attribute_group = {
397 	.attrs = nvdimm_bus_attributes,
398 };
399 EXPORT_SYMBOL_GPL(nvdimm_bus_attribute_group);
400 
401 int nvdimm_bus_add_badrange(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
402 {
403 	return badrange_add(&nvdimm_bus->badrange, addr, length);
404 }
405 EXPORT_SYMBOL_GPL(nvdimm_bus_add_badrange);
406 
407 #ifdef CONFIG_BLK_DEV_INTEGRITY
408 int nd_integrity_init(struct gendisk *disk, unsigned long meta_size)
409 {
410 	struct blk_integrity bi;
411 
412 	if (meta_size == 0)
413 		return 0;
414 
415 	memset(&bi, 0, sizeof(bi));
416 
417 	bi.tuple_size = meta_size;
418 	bi.tag_size = meta_size;
419 
420 	blk_integrity_register(disk, &bi);
421 	blk_queue_max_integrity_segments(disk->queue, 1);
422 
423 	return 0;
424 }
425 EXPORT_SYMBOL(nd_integrity_init);
426 
427 #else /* CONFIG_BLK_DEV_INTEGRITY */
428 int nd_integrity_init(struct gendisk *disk, unsigned long meta_size)
429 {
430 	return 0;
431 }
432 EXPORT_SYMBOL(nd_integrity_init);
433 
434 #endif
435 
436 static __init int libnvdimm_init(void)
437 {
438 	int rc;
439 
440 	rc = nvdimm_bus_init();
441 	if (rc)
442 		return rc;
443 	rc = nvdimm_init();
444 	if (rc)
445 		goto err_dimm;
446 	rc = nd_region_init();
447 	if (rc)
448 		goto err_region;
449 
450 	nd_label_init();
451 
452 	return 0;
453  err_region:
454 	nvdimm_exit();
455  err_dimm:
456 	nvdimm_bus_exit();
457 	return rc;
458 }
459 
460 static __exit void libnvdimm_exit(void)
461 {
462 	WARN_ON(!list_empty(&nvdimm_bus_list));
463 	nd_region_exit();
464 	nvdimm_exit();
465 	nvdimm_bus_exit();
466 	nd_region_devs_exit();
467 	nvdimm_devs_exit();
468 }
469 
470 MODULE_LICENSE("GPL v2");
471 MODULE_AUTHOR("Intel Corporation");
472 subsys_initcall(libnvdimm_init);
473 module_exit(libnvdimm_exit);
474