xref: /openbmc/linux/drivers/nvdimm/dimm_devs.c (revision f524bf271a5cf12a44253194abcf8b6688ff5b9d)
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/vmalloc.h>
15 #include <linux/device.h>
16 #include <linux/ndctl.h>
17 #include <linux/slab.h>
18 #include <linux/io.h>
19 #include <linux/fs.h>
20 #include <linux/mm.h>
21 #include "nd-core.h"
22 #include "nd.h"
23 
24 static DEFINE_IDA(dimm_ida);
25 
26 /*
27  * Retrieve bus and dimm handle and return if this bus supports
28  * get_config_data commands
29  */
30 static int __validate_dimm(struct nvdimm_drvdata *ndd)
31 {
32 	struct nvdimm *nvdimm;
33 
34 	if (!ndd)
35 		return -EINVAL;
36 
37 	nvdimm = to_nvdimm(ndd->dev);
38 
39 	if (!nvdimm->dsm_mask)
40 		return -ENXIO;
41 	if (!test_bit(ND_CMD_GET_CONFIG_DATA, nvdimm->dsm_mask))
42 		return -ENXIO;
43 
44 	return 0;
45 }
46 
47 static int validate_dimm(struct nvdimm_drvdata *ndd)
48 {
49 	int rc = __validate_dimm(ndd);
50 
51 	if (rc && ndd)
52 		dev_dbg(ndd->dev, "%pf: %s error: %d\n",
53 				__builtin_return_address(0), __func__, rc);
54 	return rc;
55 }
56 
57 /**
58  * nvdimm_init_nsarea - determine the geometry of a dimm's namespace area
59  * @nvdimm: dimm to initialize
60  */
61 int nvdimm_init_nsarea(struct nvdimm_drvdata *ndd)
62 {
63 	struct nd_cmd_get_config_size *cmd = &ndd->nsarea;
64 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
65 	struct nvdimm_bus_descriptor *nd_desc;
66 	int rc = validate_dimm(ndd);
67 
68 	if (rc)
69 		return rc;
70 
71 	if (cmd->config_size)
72 		return 0; /* already valid */
73 
74 	memset(cmd, 0, sizeof(*cmd));
75 	nd_desc = nvdimm_bus->nd_desc;
76 	return nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
77 			ND_CMD_GET_CONFIG_SIZE, cmd, sizeof(*cmd));
78 }
79 
80 int nvdimm_init_config_data(struct nvdimm_drvdata *ndd)
81 {
82 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
83 	struct nd_cmd_get_config_data_hdr *cmd;
84 	struct nvdimm_bus_descriptor *nd_desc;
85 	int rc = validate_dimm(ndd);
86 	u32 max_cmd_size, config_size;
87 	size_t offset;
88 
89 	if (rc)
90 		return rc;
91 
92 	if (ndd->data)
93 		return 0;
94 
95 	if (ndd->nsarea.status || ndd->nsarea.max_xfer == 0
96 			|| ndd->nsarea.config_size < ND_LABEL_MIN_SIZE) {
97 		dev_dbg(ndd->dev, "failed to init config data area: (%d:%d)\n",
98 				ndd->nsarea.max_xfer, ndd->nsarea.config_size);
99 		return -ENXIO;
100 	}
101 
102 	ndd->data = kmalloc(ndd->nsarea.config_size, GFP_KERNEL);
103 	if (!ndd->data)
104 		ndd->data = vmalloc(ndd->nsarea.config_size);
105 
106 	if (!ndd->data)
107 		return -ENOMEM;
108 
109 	max_cmd_size = min_t(u32, PAGE_SIZE, ndd->nsarea.max_xfer);
110 	cmd = kzalloc(max_cmd_size + sizeof(*cmd), GFP_KERNEL);
111 	if (!cmd)
112 		return -ENOMEM;
113 
114 	nd_desc = nvdimm_bus->nd_desc;
115 	for (config_size = ndd->nsarea.config_size, offset = 0;
116 			config_size; config_size -= cmd->in_length,
117 			offset += cmd->in_length) {
118 		cmd->in_length = min(config_size, max_cmd_size);
119 		cmd->in_offset = offset;
120 		rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
121 				ND_CMD_GET_CONFIG_DATA, cmd,
122 				cmd->in_length + sizeof(*cmd));
123 		if (rc || cmd->status) {
124 			rc = -ENXIO;
125 			break;
126 		}
127 		memcpy(ndd->data + offset, cmd->out_buf, cmd->in_length);
128 	}
129 	dev_dbg(ndd->dev, "%s: len: %zu rc: %d\n", __func__, offset, rc);
130 	kfree(cmd);
131 
132 	return rc;
133 }
134 
135 int nvdimm_set_config_data(struct nvdimm_drvdata *ndd, size_t offset,
136 		void *buf, size_t len)
137 {
138 	int rc = validate_dimm(ndd);
139 	size_t max_cmd_size, buf_offset;
140 	struct nd_cmd_set_config_hdr *cmd;
141 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
142 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
143 
144 	if (rc)
145 		return rc;
146 
147 	if (!ndd->data)
148 		return -ENXIO;
149 
150 	if (offset + len > ndd->nsarea.config_size)
151 		return -ENXIO;
152 
153 	max_cmd_size = min_t(u32, PAGE_SIZE, len);
154 	max_cmd_size = min_t(u32, max_cmd_size, ndd->nsarea.max_xfer);
155 	cmd = kzalloc(max_cmd_size + sizeof(*cmd) + sizeof(u32), GFP_KERNEL);
156 	if (!cmd)
157 		return -ENOMEM;
158 
159 	for (buf_offset = 0; len; len -= cmd->in_length,
160 			buf_offset += cmd->in_length) {
161 		size_t cmd_size;
162 		u32 *status;
163 
164 		cmd->in_offset = offset + buf_offset;
165 		cmd->in_length = min(max_cmd_size, len);
166 		memcpy(cmd->in_buf, buf + buf_offset, cmd->in_length);
167 
168 		/* status is output in the last 4-bytes of the command buffer */
169 		cmd_size = sizeof(*cmd) + cmd->in_length + sizeof(u32);
170 		status = ((void *) cmd) + cmd_size - sizeof(u32);
171 
172 		rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
173 				ND_CMD_SET_CONFIG_DATA, cmd, cmd_size);
174 		if (rc || *status) {
175 			rc = rc ? rc : -ENXIO;
176 			break;
177 		}
178 	}
179 	kfree(cmd);
180 
181 	return rc;
182 }
183 
184 static void nvdimm_release(struct device *dev)
185 {
186 	struct nvdimm *nvdimm = to_nvdimm(dev);
187 
188 	ida_simple_remove(&dimm_ida, nvdimm->id);
189 	kfree(nvdimm);
190 }
191 
192 static struct device_type nvdimm_device_type = {
193 	.name = "nvdimm",
194 	.release = nvdimm_release,
195 };
196 
197 bool is_nvdimm(struct device *dev)
198 {
199 	return dev->type == &nvdimm_device_type;
200 }
201 
202 struct nvdimm *to_nvdimm(struct device *dev)
203 {
204 	struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);
205 
206 	WARN_ON(!is_nvdimm(dev));
207 	return nvdimm;
208 }
209 EXPORT_SYMBOL_GPL(to_nvdimm);
210 
211 struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
212 {
213 	struct nvdimm *nvdimm = nd_mapping->nvdimm;
214 
215 	WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
216 
217 	return dev_get_drvdata(&nvdimm->dev);
218 }
219 EXPORT_SYMBOL(to_ndd);
220 
221 void nvdimm_drvdata_release(struct kref *kref)
222 {
223 	struct nvdimm_drvdata *ndd = container_of(kref, typeof(*ndd), kref);
224 	struct device *dev = ndd->dev;
225 	struct resource *res, *_r;
226 
227 	dev_dbg(dev, "%s\n", __func__);
228 
229 	nvdimm_bus_lock(dev);
230 	for_each_dpa_resource_safe(ndd, res, _r)
231 		nvdimm_free_dpa(ndd, res);
232 	nvdimm_bus_unlock(dev);
233 
234 	if (ndd->data && is_vmalloc_addr(ndd->data))
235 		vfree(ndd->data);
236 	else
237 		kfree(ndd->data);
238 	kfree(ndd);
239 	put_device(dev);
240 }
241 
242 void get_ndd(struct nvdimm_drvdata *ndd)
243 {
244 	kref_get(&ndd->kref);
245 }
246 
247 void put_ndd(struct nvdimm_drvdata *ndd)
248 {
249 	if (ndd)
250 		kref_put(&ndd->kref, nvdimm_drvdata_release);
251 }
252 
253 const char *nvdimm_name(struct nvdimm *nvdimm)
254 {
255 	return dev_name(&nvdimm->dev);
256 }
257 EXPORT_SYMBOL_GPL(nvdimm_name);
258 
259 void *nvdimm_provider_data(struct nvdimm *nvdimm)
260 {
261 	if (nvdimm)
262 		return nvdimm->provider_data;
263 	return NULL;
264 }
265 EXPORT_SYMBOL_GPL(nvdimm_provider_data);
266 
267 static ssize_t commands_show(struct device *dev,
268 		struct device_attribute *attr, char *buf)
269 {
270 	struct nvdimm *nvdimm = to_nvdimm(dev);
271 	int cmd, len = 0;
272 
273 	if (!nvdimm->dsm_mask)
274 		return sprintf(buf, "\n");
275 
276 	for_each_set_bit(cmd, nvdimm->dsm_mask, BITS_PER_LONG)
277 		len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
278 	len += sprintf(buf + len, "\n");
279 	return len;
280 }
281 static DEVICE_ATTR_RO(commands);
282 
283 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
284 		char *buf)
285 {
286 	struct nvdimm *nvdimm = to_nvdimm(dev);
287 
288 	/*
289 	 * The state may be in the process of changing, userspace should
290 	 * quiesce probing if it wants a static answer
291 	 */
292 	nvdimm_bus_lock(dev);
293 	nvdimm_bus_unlock(dev);
294 	return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
295 			? "active" : "idle");
296 }
297 static DEVICE_ATTR_RO(state);
298 
299 static struct attribute *nvdimm_attributes[] = {
300 	&dev_attr_state.attr,
301 	&dev_attr_commands.attr,
302 	NULL,
303 };
304 
305 struct attribute_group nvdimm_attribute_group = {
306 	.attrs = nvdimm_attributes,
307 };
308 EXPORT_SYMBOL_GPL(nvdimm_attribute_group);
309 
310 struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
311 		const struct attribute_group **groups, unsigned long flags,
312 		unsigned long *dsm_mask)
313 {
314 	struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
315 	struct device *dev;
316 
317 	if (!nvdimm)
318 		return NULL;
319 
320 	nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
321 	if (nvdimm->id < 0) {
322 		kfree(nvdimm);
323 		return NULL;
324 	}
325 	nvdimm->provider_data = provider_data;
326 	nvdimm->flags = flags;
327 	nvdimm->dsm_mask = dsm_mask;
328 	atomic_set(&nvdimm->busy, 0);
329 	dev = &nvdimm->dev;
330 	dev_set_name(dev, "nmem%d", nvdimm->id);
331 	dev->parent = &nvdimm_bus->dev;
332 	dev->type = &nvdimm_device_type;
333 	dev->devt = MKDEV(nvdimm_major, nvdimm->id);
334 	dev->groups = groups;
335 	nd_device_register(dev);
336 
337 	return nvdimm;
338 }
339 EXPORT_SYMBOL_GPL(nvdimm_create);
340 
341 /**
342  * nd_blk_available_dpa - account the unused dpa of BLK region
343  * @nd_mapping: container of dpa-resource-root + labels
344  *
345  * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges.
346  */
347 resource_size_t nd_blk_available_dpa(struct nd_mapping *nd_mapping)
348 {
349 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
350 	resource_size_t map_end, busy = 0, available;
351 	struct resource *res;
352 
353 	if (!ndd)
354 		return 0;
355 
356 	map_end = nd_mapping->start + nd_mapping->size - 1;
357 	for_each_dpa_resource(ndd, res)
358 		if (res->start >= nd_mapping->start && res->start < map_end) {
359 			resource_size_t end = min(map_end, res->end);
360 
361 			busy += end - res->start + 1;
362 		} else if (res->end >= nd_mapping->start
363 				&& res->end <= map_end) {
364 			busy += res->end - nd_mapping->start;
365 		} else if (nd_mapping->start > res->start
366 				&& nd_mapping->start < res->end) {
367 			/* total eclipse of the BLK region mapping */
368 			busy += nd_mapping->size;
369 		}
370 
371 	available = map_end - nd_mapping->start + 1;
372 	if (busy < available)
373 		return available - busy;
374 	return 0;
375 }
376 
377 /**
378  * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
379  * @nd_mapping: container of dpa-resource-root + labels
380  * @nd_region: constrain available space check to this reference region
381  * @overlap: calculate available space assuming this level of overlap
382  *
383  * Validate that a PMEM label, if present, aligns with the start of an
384  * interleave set and truncate the available size at the lowest BLK
385  * overlap point.
386  *
387  * The expectation is that this routine is called multiple times as it
388  * probes for the largest BLK encroachment for any single member DIMM of
389  * the interleave set.  Once that value is determined the PMEM-limit for
390  * the set can be established.
391  */
392 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
393 		struct nd_mapping *nd_mapping, resource_size_t *overlap)
394 {
395 	resource_size_t map_start, map_end, busy = 0, available, blk_start;
396 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
397 	struct resource *res;
398 	const char *reason;
399 
400 	if (!ndd)
401 		return 0;
402 
403 	map_start = nd_mapping->start;
404 	map_end = map_start + nd_mapping->size - 1;
405 	blk_start = max(map_start, map_end + 1 - *overlap);
406 	for_each_dpa_resource(ndd, res)
407 		if (res->start >= map_start && res->start < map_end) {
408 			if (strncmp(res->name, "blk", 3) == 0)
409 				blk_start = min(blk_start, res->start);
410 			else if (res->start != map_start) {
411 				reason = "misaligned to iset";
412 				goto err;
413 			} else {
414 				if (busy) {
415 					reason = "duplicate overlapping PMEM reservations?";
416 					goto err;
417 				}
418 				busy += resource_size(res);
419 				continue;
420 			}
421 		} else if (res->end >= map_start && res->end <= map_end) {
422 			if (strncmp(res->name, "blk", 3) == 0) {
423 				/*
424 				 * If a BLK allocation overlaps the start of
425 				 * PMEM the entire interleave set may now only
426 				 * be used for BLK.
427 				 */
428 				blk_start = map_start;
429 			} else {
430 				reason = "misaligned to iset";
431 				goto err;
432 			}
433 		} else if (map_start > res->start && map_start < res->end) {
434 			/* total eclipse of the mapping */
435 			busy += nd_mapping->size;
436 			blk_start = map_start;
437 		}
438 
439 	*overlap = map_end + 1 - blk_start;
440 	available = blk_start - map_start;
441 	if (busy < available)
442 		return available - busy;
443 	return 0;
444 
445  err:
446 	/*
447 	 * Something is wrong, PMEM must align with the start of the
448 	 * interleave set, and there can only be one allocation per set.
449 	 */
450 	nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
451 	return 0;
452 }
453 
454 void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
455 {
456 	WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
457 	kfree(res->name);
458 	__release_region(&ndd->dpa, res->start, resource_size(res));
459 }
460 
461 struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
462 		struct nd_label_id *label_id, resource_size_t start,
463 		resource_size_t n)
464 {
465 	char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
466 	struct resource *res;
467 
468 	if (!name)
469 		return NULL;
470 
471 	WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
472 	res = __request_region(&ndd->dpa, start, n, name, 0);
473 	if (!res)
474 		kfree(name);
475 	return res;
476 }
477 
478 /**
479  * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
480  * @nvdimm: container of dpa-resource-root + labels
481  * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
482  */
483 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
484 		struct nd_label_id *label_id)
485 {
486 	resource_size_t allocated = 0;
487 	struct resource *res;
488 
489 	for_each_dpa_resource(ndd, res)
490 		if (strcmp(res->name, label_id->id) == 0)
491 			allocated += resource_size(res);
492 
493 	return allocated;
494 }
495 
496 static int count_dimms(struct device *dev, void *c)
497 {
498 	int *count = c;
499 
500 	if (is_nvdimm(dev))
501 		(*count)++;
502 	return 0;
503 }
504 
505 int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
506 {
507 	int count = 0;
508 	/* Flush any possible dimm registration failures */
509 	nd_synchronize();
510 
511 	device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
512 	dev_dbg(&nvdimm_bus->dev, "%s: count: %d\n", __func__, count);
513 	if (count != dimm_count)
514 		return -ENXIO;
515 	return 0;
516 }
517 EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);
518