1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4 */
5#include <linux/blkdev.h>
6#include <linux/device.h>
7#include <linux/sizes.h>
8#include <linux/slab.h>
9#include <linux/fs.h>
10#include <linux/mm.h>
11#include "nd-core.h"
12#include "btt.h"
13#include "nd.h"
14
15static void nd_btt_release(struct device *dev)
16{
17 struct nd_region *nd_region = to_nd_region(dev: dev->parent);
18 struct nd_btt *nd_btt = to_nd_btt(dev);
19
20 dev_dbg(dev, "trace\n");
21 nd_detach_ndns(dev: &nd_btt->dev, ndns: &nd_btt->ndns);
22 ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
23 kfree(objp: nd_btt->uuid);
24 kfree(objp: nd_btt);
25}
26
27struct nd_btt *to_nd_btt(struct device *dev)
28{
29 struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev);
30
31 WARN_ON(!is_nd_btt(dev));
32 return nd_btt;
33}
34EXPORT_SYMBOL(to_nd_btt);
35
36static const unsigned long btt_lbasize_supported[] = { 512, 520, 528,
37 4096, 4104, 4160, 4224, 0 };
38
39static ssize_t sector_size_show(struct device *dev,
40 struct device_attribute *attr, char *buf)
41{
42 struct nd_btt *nd_btt = to_nd_btt(dev);
43
44 return nd_size_select_show(current_size: nd_btt->lbasize, supported: btt_lbasize_supported, buf);
45}
46
47static ssize_t sector_size_store(struct device *dev,
48 struct device_attribute *attr, const char *buf, size_t len)
49{
50 struct nd_btt *nd_btt = to_nd_btt(dev);
51 ssize_t rc;
52
53 device_lock(dev);
54 nvdimm_bus_lock(dev);
55 rc = nd_size_select_store(dev, buf, current_size: &nd_btt->lbasize,
56 supported: btt_lbasize_supported);
57 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
58 buf[len - 1] == '\n' ? "" : "\n");
59 nvdimm_bus_unlock(dev);
60 device_unlock(dev);
61
62 return rc ? rc : len;
63}
64static DEVICE_ATTR_RW(sector_size);
65
66static ssize_t uuid_show(struct device *dev,
67 struct device_attribute *attr, char *buf)
68{
69 struct nd_btt *nd_btt = to_nd_btt(dev);
70
71 if (nd_btt->uuid)
72 return sprintf(buf, fmt: "%pUb\n", nd_btt->uuid);
73 return sprintf(buf, fmt: "\n");
74}
75
76static ssize_t uuid_store(struct device *dev,
77 struct device_attribute *attr, const char *buf, size_t len)
78{
79 struct nd_btt *nd_btt = to_nd_btt(dev);
80 ssize_t rc;
81
82 device_lock(dev);
83 rc = nd_uuid_store(dev, uuid_out: &nd_btt->uuid, buf, len);
84 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
85 buf[len - 1] == '\n' ? "" : "\n");
86 device_unlock(dev);
87
88 return rc ? rc : len;
89}
90static DEVICE_ATTR_RW(uuid);
91
92static ssize_t namespace_show(struct device *dev,
93 struct device_attribute *attr, char *buf)
94{
95 struct nd_btt *nd_btt = to_nd_btt(dev);
96 ssize_t rc;
97
98 nvdimm_bus_lock(dev);
99 rc = sprintf(buf, fmt: "%s\n", nd_btt->ndns
100 ? dev_name(dev: &nd_btt->ndns->dev) : "");
101 nvdimm_bus_unlock(dev);
102 return rc;
103}
104
105static ssize_t namespace_store(struct device *dev,
106 struct device_attribute *attr, const char *buf, size_t len)
107{
108 struct nd_btt *nd_btt = to_nd_btt(dev);
109 ssize_t rc;
110
111 device_lock(dev);
112 nvdimm_bus_lock(dev);
113 rc = nd_namespace_store(dev, ndns: &nd_btt->ndns, buf, len);
114 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
115 buf[len - 1] == '\n' ? "" : "\n");
116 nvdimm_bus_unlock(dev);
117 device_unlock(dev);
118
119 return rc;
120}
121static DEVICE_ATTR_RW(namespace);
122
123static ssize_t size_show(struct device *dev,
124 struct device_attribute *attr, char *buf)
125{
126 struct nd_btt *nd_btt = to_nd_btt(dev);
127 ssize_t rc;
128
129 device_lock(dev);
130 if (dev->driver)
131 rc = sprintf(buf, fmt: "%llu\n", nd_btt->size);
132 else {
133 /* no size to convey if the btt instance is disabled */
134 rc = -ENXIO;
135 }
136 device_unlock(dev);
137
138 return rc;
139}
140static DEVICE_ATTR_RO(size);
141
142static ssize_t log_zero_flags_show(struct device *dev,
143 struct device_attribute *attr, char *buf)
144{
145 return sprintf(buf, fmt: "Y\n");
146}
147static DEVICE_ATTR_RO(log_zero_flags);
148
149static struct attribute *nd_btt_attributes[] = {
150 &dev_attr_sector_size.attr,
151 &dev_attr_namespace.attr,
152 &dev_attr_uuid.attr,
153 &dev_attr_size.attr,
154 &dev_attr_log_zero_flags.attr,
155 NULL,
156};
157
158static struct attribute_group nd_btt_attribute_group = {
159 .attrs = nd_btt_attributes,
160};
161
162static const struct attribute_group *nd_btt_attribute_groups[] = {
163 &nd_btt_attribute_group,
164 &nd_device_attribute_group,
165 &nd_numa_attribute_group,
166 NULL,
167};
168
169static const struct device_type nd_btt_device_type = {
170 .name = "nd_btt",
171 .release = nd_btt_release,
172 .groups = nd_btt_attribute_groups,
173};
174
175bool is_nd_btt(struct device *dev)
176{
177 return dev->type == &nd_btt_device_type;
178}
179EXPORT_SYMBOL(is_nd_btt);
180
181static struct lock_class_key nvdimm_btt_key;
182
183static struct device *__nd_btt_create(struct nd_region *nd_region,
184 unsigned long lbasize, uuid_t *uuid,
185 struct nd_namespace_common *ndns)
186{
187 struct nd_btt *nd_btt;
188 struct device *dev;
189
190 nd_btt = kzalloc(size: sizeof(*nd_btt), GFP_KERNEL);
191 if (!nd_btt)
192 return NULL;
193
194 nd_btt->id = ida_simple_get(&nd_region->btt_ida, 0, 0, GFP_KERNEL);
195 if (nd_btt->id < 0)
196 goto out_nd_btt;
197
198 nd_btt->lbasize = lbasize;
199 if (uuid) {
200 uuid = kmemdup(p: uuid, size: 16, GFP_KERNEL);
201 if (!uuid)
202 goto out_put_id;
203 }
204 nd_btt->uuid = uuid;
205 dev = &nd_btt->dev;
206 dev_set_name(dev, name: "btt%d.%d", nd_region->id, nd_btt->id);
207 dev->parent = &nd_region->dev;
208 dev->type = &nd_btt_device_type;
209 device_initialize(dev: &nd_btt->dev);
210 lockdep_set_class(&nd_btt->dev.mutex, &nvdimm_btt_key);
211 if (ndns && !__nd_attach_ndns(dev: &nd_btt->dev, attach: ndns, ndns: &nd_btt->ndns)) {
212 dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
213 dev_name(ndns->claim));
214 put_device(dev);
215 return NULL;
216 }
217 return dev;
218
219out_put_id:
220 ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
221
222out_nd_btt:
223 kfree(objp: nd_btt);
224 return NULL;
225}
226
227struct device *nd_btt_create(struct nd_region *nd_region)
228{
229 struct device *dev = __nd_btt_create(nd_region, lbasize: 0, NULL, NULL);
230
231 nd_device_register(dev);
232 return dev;
233}
234
235/**
236 * nd_btt_arena_is_valid - check if the metadata layout is valid
237 * @nd_btt: device with BTT geometry and backing device info
238 * @super: pointer to the arena's info block being tested
239 *
240 * Check consistency of the btt info block with itself by validating
241 * the checksum, and with the parent namespace by verifying the
242 * parent_uuid contained in the info block with the one supplied in.
243 *
244 * Returns:
245 * false for an invalid info block, true for a valid one
246 */
247bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
248{
249 const uuid_t *ns_uuid = nd_dev_to_uuid(dev: &nd_btt->ndns->dev);
250 uuid_t parent_uuid;
251 u64 checksum;
252
253 if (memcmp(p: super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
254 return false;
255
256 import_uuid(dst: &parent_uuid, src: super->parent_uuid);
257 if (!uuid_is_null(uuid: &parent_uuid))
258 if (!uuid_equal(u1: &parent_uuid, u2: ns_uuid))
259 return false;
260
261 checksum = le64_to_cpu(super->checksum);
262 super->checksum = 0;
263 if (checksum != nd_sb_checksum(sb: (struct nd_gen_sb *) super))
264 return false;
265 super->checksum = cpu_to_le64(checksum);
266
267 /* TODO: figure out action for this */
268 if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
269 dev_info(&nd_btt->dev, "Found arena with an error flag\n");
270
271 return true;
272}
273EXPORT_SYMBOL(nd_btt_arena_is_valid);
274
275int nd_btt_version(struct nd_btt *nd_btt, struct nd_namespace_common *ndns,
276 struct btt_sb *btt_sb)
277{
278 if (ndns->claim_class == NVDIMM_CCLASS_BTT2) {
279 /* Probe/setup for BTT v2.0 */
280 nd_btt->initial_offset = 0;
281 nd_btt->version_major = 2;
282 nd_btt->version_minor = 0;
283 if (nvdimm_read_bytes(ndns, offset: 0, buf: btt_sb, size: sizeof(*btt_sb), flags: 0))
284 return -ENXIO;
285 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
286 return -ENODEV;
287 if ((le16_to_cpu(btt_sb->version_major) != 2) ||
288 (le16_to_cpu(btt_sb->version_minor) != 0))
289 return -ENODEV;
290 } else {
291 /*
292 * Probe/setup for BTT v1.1 (NVDIMM_CCLASS_NONE or
293 * NVDIMM_CCLASS_BTT)
294 */
295 nd_btt->initial_offset = SZ_4K;
296 nd_btt->version_major = 1;
297 nd_btt->version_minor = 1;
298 if (nvdimm_read_bytes(ndns, SZ_4K, buf: btt_sb, size: sizeof(*btt_sb), flags: 0))
299 return -ENXIO;
300 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
301 return -ENODEV;
302 if ((le16_to_cpu(btt_sb->version_major) != 1) ||
303 (le16_to_cpu(btt_sb->version_minor) != 1))
304 return -ENODEV;
305 }
306 return 0;
307}
308EXPORT_SYMBOL(nd_btt_version);
309
310static int __nd_btt_probe(struct nd_btt *nd_btt,
311 struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
312{
313 int rc;
314
315 if (!btt_sb || !ndns || !nd_btt)
316 return -ENODEV;
317
318 if (nvdimm_namespace_capacity(ndns) < SZ_16M)
319 return -ENXIO;
320
321 rc = nd_btt_version(nd_btt, ndns, btt_sb);
322 if (rc < 0)
323 return rc;
324
325 nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
326 nd_btt->uuid = kmemdup(p: &btt_sb->uuid, size: sizeof(uuid_t), GFP_KERNEL);
327 if (!nd_btt->uuid)
328 return -ENOMEM;
329
330 nd_device_register(dev: &nd_btt->dev);
331
332 return 0;
333}
334
335int nd_btt_probe(struct device *dev, struct nd_namespace_common *ndns)
336{
337 int rc;
338 struct device *btt_dev;
339 struct btt_sb *btt_sb;
340 struct nd_region *nd_region = to_nd_region(dev: ndns->dev.parent);
341
342 if (ndns->force_raw)
343 return -ENODEV;
344
345 switch (ndns->claim_class) {
346 case NVDIMM_CCLASS_NONE:
347 case NVDIMM_CCLASS_BTT:
348 case NVDIMM_CCLASS_BTT2:
349 break;
350 default:
351 return -ENODEV;
352 }
353
354 nvdimm_bus_lock(dev: &ndns->dev);
355 btt_dev = __nd_btt_create(nd_region, lbasize: 0, NULL, ndns);
356 nvdimm_bus_unlock(dev: &ndns->dev);
357 if (!btt_dev)
358 return -ENOMEM;
359 btt_sb = devm_kzalloc(dev, size: sizeof(*btt_sb), GFP_KERNEL);
360 rc = __nd_btt_probe(nd_btt: to_nd_btt(btt_dev), ndns, btt_sb);
361 dev_dbg(dev, "btt: %s\n", rc == 0 ? dev_name(btt_dev) : "<none>");
362 if (rc < 0) {
363 struct nd_btt *nd_btt = to_nd_btt(btt_dev);
364
365 nd_detach_ndns(dev: btt_dev, ndns: &nd_btt->ndns);
366 put_device(dev: btt_dev);
367 }
368
369 return rc;
370}
371EXPORT_SYMBOL(nd_btt_probe);
372

source code of linux/drivers/nvdimm/btt_devs.c