xref: /openbmc/linux/drivers/nvdimm/dimm_devs.c (revision 1b40e09a1232de537b193fa1b6b3ef16d3a1e397)
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 static void nvdimm_release(struct device *dev)
136 {
137 	struct nvdimm *nvdimm = to_nvdimm(dev);
138 
139 	ida_simple_remove(&dimm_ida, nvdimm->id);
140 	kfree(nvdimm);
141 }
142 
143 static struct device_type nvdimm_device_type = {
144 	.name = "nvdimm",
145 	.release = nvdimm_release,
146 };
147 
148 bool is_nvdimm(struct device *dev)
149 {
150 	return dev->type == &nvdimm_device_type;
151 }
152 
153 struct nvdimm *to_nvdimm(struct device *dev)
154 {
155 	struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);
156 
157 	WARN_ON(!is_nvdimm(dev));
158 	return nvdimm;
159 }
160 EXPORT_SYMBOL_GPL(to_nvdimm);
161 
162 struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
163 {
164 	struct nvdimm *nvdimm = nd_mapping->nvdimm;
165 
166 	WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
167 
168 	return dev_get_drvdata(&nvdimm->dev);
169 }
170 EXPORT_SYMBOL(to_ndd);
171 
172 void nvdimm_drvdata_release(struct kref *kref)
173 {
174 	struct nvdimm_drvdata *ndd = container_of(kref, typeof(*ndd), kref);
175 	struct device *dev = ndd->dev;
176 	struct resource *res, *_r;
177 
178 	dev_dbg(dev, "%s\n", __func__);
179 
180 	nvdimm_bus_lock(dev);
181 	for_each_dpa_resource_safe(ndd, res, _r)
182 		nvdimm_free_dpa(ndd, res);
183 	nvdimm_bus_unlock(dev);
184 
185 	if (ndd->data && is_vmalloc_addr(ndd->data))
186 		vfree(ndd->data);
187 	else
188 		kfree(ndd->data);
189 	kfree(ndd);
190 	put_device(dev);
191 }
192 
193 void get_ndd(struct nvdimm_drvdata *ndd)
194 {
195 	kref_get(&ndd->kref);
196 }
197 
198 void put_ndd(struct nvdimm_drvdata *ndd)
199 {
200 	if (ndd)
201 		kref_put(&ndd->kref, nvdimm_drvdata_release);
202 }
203 
204 const char *nvdimm_name(struct nvdimm *nvdimm)
205 {
206 	return dev_name(&nvdimm->dev);
207 }
208 EXPORT_SYMBOL_GPL(nvdimm_name);
209 
210 void *nvdimm_provider_data(struct nvdimm *nvdimm)
211 {
212 	if (nvdimm)
213 		return nvdimm->provider_data;
214 	return NULL;
215 }
216 EXPORT_SYMBOL_GPL(nvdimm_provider_data);
217 
218 static ssize_t commands_show(struct device *dev,
219 		struct device_attribute *attr, char *buf)
220 {
221 	struct nvdimm *nvdimm = to_nvdimm(dev);
222 	int cmd, len = 0;
223 
224 	if (!nvdimm->dsm_mask)
225 		return sprintf(buf, "\n");
226 
227 	for_each_set_bit(cmd, nvdimm->dsm_mask, BITS_PER_LONG)
228 		len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
229 	len += sprintf(buf + len, "\n");
230 	return len;
231 }
232 static DEVICE_ATTR_RO(commands);
233 
234 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
235 		char *buf)
236 {
237 	struct nvdimm *nvdimm = to_nvdimm(dev);
238 
239 	/*
240 	 * The state may be in the process of changing, userspace should
241 	 * quiesce probing if it wants a static answer
242 	 */
243 	nvdimm_bus_lock(dev);
244 	nvdimm_bus_unlock(dev);
245 	return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
246 			? "active" : "idle");
247 }
248 static DEVICE_ATTR_RO(state);
249 
250 static struct attribute *nvdimm_attributes[] = {
251 	&dev_attr_state.attr,
252 	&dev_attr_commands.attr,
253 	NULL,
254 };
255 
256 struct attribute_group nvdimm_attribute_group = {
257 	.attrs = nvdimm_attributes,
258 };
259 EXPORT_SYMBOL_GPL(nvdimm_attribute_group);
260 
261 struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
262 		const struct attribute_group **groups, unsigned long flags,
263 		unsigned long *dsm_mask)
264 {
265 	struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
266 	struct device *dev;
267 
268 	if (!nvdimm)
269 		return NULL;
270 
271 	nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
272 	if (nvdimm->id < 0) {
273 		kfree(nvdimm);
274 		return NULL;
275 	}
276 	nvdimm->provider_data = provider_data;
277 	nvdimm->flags = flags;
278 	nvdimm->dsm_mask = dsm_mask;
279 	atomic_set(&nvdimm->busy, 0);
280 	dev = &nvdimm->dev;
281 	dev_set_name(dev, "nmem%d", nvdimm->id);
282 	dev->parent = &nvdimm_bus->dev;
283 	dev->type = &nvdimm_device_type;
284 	dev->devt = MKDEV(nvdimm_major, nvdimm->id);
285 	dev->groups = groups;
286 	nd_device_register(dev);
287 
288 	return nvdimm;
289 }
290 EXPORT_SYMBOL_GPL(nvdimm_create);
291 
292 /**
293  * nd_blk_available_dpa - account the unused dpa of BLK region
294  * @nd_mapping: container of dpa-resource-root + labels
295  *
296  * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges.
297  */
298 resource_size_t nd_blk_available_dpa(struct nd_mapping *nd_mapping)
299 {
300 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
301 	resource_size_t map_end, busy = 0, available;
302 	struct resource *res;
303 
304 	if (!ndd)
305 		return 0;
306 
307 	map_end = nd_mapping->start + nd_mapping->size - 1;
308 	for_each_dpa_resource(ndd, res)
309 		if (res->start >= nd_mapping->start && res->start < map_end) {
310 			resource_size_t end = min(map_end, res->end);
311 
312 			busy += end - res->start + 1;
313 		} else if (res->end >= nd_mapping->start
314 				&& res->end <= map_end) {
315 			busy += res->end - nd_mapping->start;
316 		} else if (nd_mapping->start > res->start
317 				&& nd_mapping->start < res->end) {
318 			/* total eclipse of the BLK region mapping */
319 			busy += nd_mapping->size;
320 		}
321 
322 	available = map_end - nd_mapping->start + 1;
323 	if (busy < available)
324 		return available - busy;
325 	return 0;
326 }
327 
328 /**
329  * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
330  * @nd_mapping: container of dpa-resource-root + labels
331  * @nd_region: constrain available space check to this reference region
332  * @overlap: calculate available space assuming this level of overlap
333  *
334  * Validate that a PMEM label, if present, aligns with the start of an
335  * interleave set and truncate the available size at the lowest BLK
336  * overlap point.
337  *
338  * The expectation is that this routine is called multiple times as it
339  * probes for the largest BLK encroachment for any single member DIMM of
340  * the interleave set.  Once that value is determined the PMEM-limit for
341  * the set can be established.
342  */
343 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
344 		struct nd_mapping *nd_mapping, resource_size_t *overlap)
345 {
346 	resource_size_t map_start, map_end, busy = 0, available, blk_start;
347 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
348 	struct resource *res;
349 	const char *reason;
350 
351 	if (!ndd)
352 		return 0;
353 
354 	map_start = nd_mapping->start;
355 	map_end = map_start + nd_mapping->size - 1;
356 	blk_start = max(map_start, map_end + 1 - *overlap);
357 	for_each_dpa_resource(ndd, res)
358 		if (res->start >= map_start && res->start < map_end) {
359 			if (strncmp(res->name, "blk", 3) == 0)
360 				blk_start = min(blk_start, res->start);
361 			else if (res->start != map_start) {
362 				reason = "misaligned to iset";
363 				goto err;
364 			} else {
365 				if (busy) {
366 					reason = "duplicate overlapping PMEM reservations?";
367 					goto err;
368 				}
369 				busy += resource_size(res);
370 				continue;
371 			}
372 		} else if (res->end >= map_start && res->end <= map_end) {
373 			if (strncmp(res->name, "blk", 3) == 0) {
374 				/*
375 				 * If a BLK allocation overlaps the start of
376 				 * PMEM the entire interleave set may now only
377 				 * be used for BLK.
378 				 */
379 				blk_start = map_start;
380 			} else {
381 				reason = "misaligned to iset";
382 				goto err;
383 			}
384 		} else if (map_start > res->start && map_start < res->end) {
385 			/* total eclipse of the mapping */
386 			busy += nd_mapping->size;
387 			blk_start = map_start;
388 		}
389 
390 	*overlap = map_end + 1 - blk_start;
391 	available = blk_start - map_start;
392 	if (busy < available)
393 		return available - busy;
394 	return 0;
395 
396  err:
397 	/*
398 	 * Something is wrong, PMEM must align with the start of the
399 	 * interleave set, and there can only be one allocation per set.
400 	 */
401 	nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
402 	return 0;
403 }
404 
405 void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
406 {
407 	WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
408 	kfree(res->name);
409 	__release_region(&ndd->dpa, res->start, resource_size(res));
410 }
411 
412 struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
413 		struct nd_label_id *label_id, resource_size_t start,
414 		resource_size_t n)
415 {
416 	char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
417 	struct resource *res;
418 
419 	if (!name)
420 		return NULL;
421 
422 	WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
423 	res = __request_region(&ndd->dpa, start, n, name, 0);
424 	if (!res)
425 		kfree(name);
426 	return res;
427 }
428 
429 /**
430  * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
431  * @nvdimm: container of dpa-resource-root + labels
432  * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
433  */
434 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
435 		struct nd_label_id *label_id)
436 {
437 	resource_size_t allocated = 0;
438 	struct resource *res;
439 
440 	for_each_dpa_resource(ndd, res)
441 		if (strcmp(res->name, label_id->id) == 0)
442 			allocated += resource_size(res);
443 
444 	return allocated;
445 }
446 
447 static int count_dimms(struct device *dev, void *c)
448 {
449 	int *count = c;
450 
451 	if (is_nvdimm(dev))
452 		(*count)++;
453 	return 0;
454 }
455 
456 int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
457 {
458 	int count = 0;
459 	/* Flush any possible dimm registration failures */
460 	nd_synchronize();
461 
462 	device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
463 	dev_dbg(&nvdimm_bus->dev, "%s: count: %d\n", __func__, count);
464 	if (count != dimm_count)
465 		return -ENXIO;
466 	return 0;
467 }
468 EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);
469