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/genhd.h>
8 #include <linux/sizes.h>
9 #include <linux/slab.h>
10 #include <linux/fs.h>
11 #include <linux/mm.h>
12 #include "nd-core.h"
13 #include "btt.h"
14 #include "nd.h"
15
nd_btt_release(struct device * dev)16 static void nd_btt_release(struct device *dev)
17 {
18 struct nd_region *nd_region = to_nd_region(dev->parent);
19 struct nd_btt *nd_btt = to_nd_btt(dev);
20
21 dev_dbg(dev, "trace\n");
22 nd_detach_ndns(&nd_btt->dev, &nd_btt->ndns);
23 ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
24 kfree(nd_btt->uuid);
25 kfree(nd_btt);
26 }
27
to_nd_btt(struct device * dev)28 struct nd_btt *to_nd_btt(struct device *dev)
29 {
30 struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev);
31
32 WARN_ON(!is_nd_btt(dev));
33 return nd_btt;
34 }
35 EXPORT_SYMBOL(to_nd_btt);
36
37 static const unsigned long btt_lbasize_supported[] = { 512, 520, 528,
38 4096, 4104, 4160, 4224, 0 };
39
sector_size_show(struct device * dev,struct device_attribute * attr,char * buf)40 static ssize_t sector_size_show(struct device *dev,
41 struct device_attribute *attr, char *buf)
42 {
43 struct nd_btt *nd_btt = to_nd_btt(dev);
44
45 return nd_size_select_show(nd_btt->lbasize, btt_lbasize_supported, buf);
46 }
47
sector_size_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)48 static ssize_t sector_size_store(struct device *dev,
49 struct device_attribute *attr, const char *buf, size_t len)
50 {
51 struct nd_btt *nd_btt = to_nd_btt(dev);
52 ssize_t rc;
53
54 nd_device_lock(dev);
55 nvdimm_bus_lock(dev);
56 rc = nd_size_select_store(dev, buf, &nd_btt->lbasize,
57 btt_lbasize_supported);
58 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
59 buf[len - 1] == '\n' ? "" : "\n");
60 nvdimm_bus_unlock(dev);
61 nd_device_unlock(dev);
62
63 return rc ? rc : len;
64 }
65 static DEVICE_ATTR_RW(sector_size);
66
uuid_show(struct device * dev,struct device_attribute * attr,char * buf)67 static ssize_t uuid_show(struct device *dev,
68 struct device_attribute *attr, char *buf)
69 {
70 struct nd_btt *nd_btt = to_nd_btt(dev);
71
72 if (nd_btt->uuid)
73 return sprintf(buf, "%pUb\n", nd_btt->uuid);
74 return sprintf(buf, "\n");
75 }
76
uuid_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)77 static ssize_t uuid_store(struct device *dev,
78 struct device_attribute *attr, const char *buf, size_t len)
79 {
80 struct nd_btt *nd_btt = to_nd_btt(dev);
81 ssize_t rc;
82
83 nd_device_lock(dev);
84 rc = nd_uuid_store(dev, &nd_btt->uuid, buf, len);
85 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
86 buf[len - 1] == '\n' ? "" : "\n");
87 nd_device_unlock(dev);
88
89 return rc ? rc : len;
90 }
91 static DEVICE_ATTR_RW(uuid);
92
namespace_show(struct device * dev,struct device_attribute * attr,char * buf)93 static ssize_t namespace_show(struct device *dev,
94 struct device_attribute *attr, char *buf)
95 {
96 struct nd_btt *nd_btt = to_nd_btt(dev);
97 ssize_t rc;
98
99 nvdimm_bus_lock(dev);
100 rc = sprintf(buf, "%s\n", nd_btt->ndns
101 ? dev_name(&nd_btt->ndns->dev) : "");
102 nvdimm_bus_unlock(dev);
103 return rc;
104 }
105
namespace_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)106 static ssize_t namespace_store(struct device *dev,
107 struct device_attribute *attr, const char *buf, size_t len)
108 {
109 struct nd_btt *nd_btt = to_nd_btt(dev);
110 ssize_t rc;
111
112 nd_device_lock(dev);
113 nvdimm_bus_lock(dev);
114 rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
115 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
116 buf[len - 1] == '\n' ? "" : "\n");
117 nvdimm_bus_unlock(dev);
118 nd_device_unlock(dev);
119
120 return rc;
121 }
122 static DEVICE_ATTR_RW(namespace);
123
size_show(struct device * dev,struct device_attribute * attr,char * buf)124 static ssize_t size_show(struct device *dev,
125 struct device_attribute *attr, char *buf)
126 {
127 struct nd_btt *nd_btt = to_nd_btt(dev);
128 ssize_t rc;
129
130 nd_device_lock(dev);
131 if (dev->driver)
132 rc = sprintf(buf, "%llu\n", nd_btt->size);
133 else {
134 /* no size to convey if the btt instance is disabled */
135 rc = -ENXIO;
136 }
137 nd_device_unlock(dev);
138
139 return rc;
140 }
141 static DEVICE_ATTR_RO(size);
142
log_zero_flags_show(struct device * dev,struct device_attribute * attr,char * buf)143 static ssize_t log_zero_flags_show(struct device *dev,
144 struct device_attribute *attr, char *buf)
145 {
146 return sprintf(buf, "Y\n");
147 }
148 static DEVICE_ATTR_RO(log_zero_flags);
149
150 static struct attribute *nd_btt_attributes[] = {
151 &dev_attr_sector_size.attr,
152 &dev_attr_namespace.attr,
153 &dev_attr_uuid.attr,
154 &dev_attr_size.attr,
155 &dev_attr_log_zero_flags.attr,
156 NULL,
157 };
158
159 static struct attribute_group nd_btt_attribute_group = {
160 .attrs = nd_btt_attributes,
161 };
162
163 static const struct attribute_group *nd_btt_attribute_groups[] = {
164 &nd_btt_attribute_group,
165 &nd_device_attribute_group,
166 &nd_numa_attribute_group,
167 NULL,
168 };
169
170 static const struct device_type nd_btt_device_type = {
171 .name = "nd_btt",
172 .release = nd_btt_release,
173 .groups = nd_btt_attribute_groups,
174 };
175
is_nd_btt(struct device * dev)176 bool is_nd_btt(struct device *dev)
177 {
178 return dev->type == &nd_btt_device_type;
179 }
180 EXPORT_SYMBOL(is_nd_btt);
181
__nd_btt_create(struct nd_region * nd_region,unsigned long lbasize,u8 * uuid,struct nd_namespace_common * ndns)182 static struct device *__nd_btt_create(struct nd_region *nd_region,
183 unsigned long lbasize, u8 *uuid,
184 struct nd_namespace_common *ndns)
185 {
186 struct nd_btt *nd_btt;
187 struct device *dev;
188
189 nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL);
190 if (!nd_btt)
191 return NULL;
192
193 nd_btt->id = ida_simple_get(&nd_region->btt_ida, 0, 0, GFP_KERNEL);
194 if (nd_btt->id < 0)
195 goto out_nd_btt;
196
197 nd_btt->lbasize = lbasize;
198 if (uuid) {
199 uuid = kmemdup(uuid, 16, GFP_KERNEL);
200 if (!uuid)
201 goto out_put_id;
202 }
203 nd_btt->uuid = uuid;
204 dev = &nd_btt->dev;
205 dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id);
206 dev->parent = &nd_region->dev;
207 dev->type = &nd_btt_device_type;
208 device_initialize(&nd_btt->dev);
209 if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) {
210 dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
211 dev_name(ndns->claim));
212 put_device(dev);
213 return NULL;
214 }
215 return dev;
216
217 out_put_id:
218 ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
219
220 out_nd_btt:
221 kfree(nd_btt);
222 return NULL;
223 }
224
nd_btt_create(struct nd_region * nd_region)225 struct device *nd_btt_create(struct nd_region *nd_region)
226 {
227 struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL);
228
229 __nd_device_register(dev);
230 return dev;
231 }
232
233 /**
234 * nd_btt_arena_is_valid - check if the metadata layout is valid
235 * @nd_btt: device with BTT geometry and backing device info
236 * @super: pointer to the arena's info block being tested
237 *
238 * Check consistency of the btt info block with itself by validating
239 * the checksum, and with the parent namespace by verifying the
240 * parent_uuid contained in the info block with the one supplied in.
241 *
242 * Returns:
243 * false for an invalid info block, true for a valid one
244 */
nd_btt_arena_is_valid(struct nd_btt * nd_btt,struct btt_sb * super)245 bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
246 {
247 const u8 *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
248 u64 checksum;
249
250 if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
251 return false;
252
253 if (!guid_is_null((guid_t *)&super->parent_uuid))
254 if (memcmp(super->parent_uuid, parent_uuid, 16) != 0)
255 return false;
256
257 checksum = le64_to_cpu(super->checksum);
258 super->checksum = 0;
259 if (checksum != nd_sb_checksum((struct nd_gen_sb *) super))
260 return false;
261 super->checksum = cpu_to_le64(checksum);
262
263 /* TODO: figure out action for this */
264 if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
265 dev_info(&nd_btt->dev, "Found arena with an error flag\n");
266
267 return true;
268 }
269 EXPORT_SYMBOL(nd_btt_arena_is_valid);
270
nd_btt_version(struct nd_btt * nd_btt,struct nd_namespace_common * ndns,struct btt_sb * btt_sb)271 int nd_btt_version(struct nd_btt *nd_btt, struct nd_namespace_common *ndns,
272 struct btt_sb *btt_sb)
273 {
274 if (ndns->claim_class == NVDIMM_CCLASS_BTT2) {
275 /* Probe/setup for BTT v2.0 */
276 nd_btt->initial_offset = 0;
277 nd_btt->version_major = 2;
278 nd_btt->version_minor = 0;
279 if (nvdimm_read_bytes(ndns, 0, btt_sb, sizeof(*btt_sb), 0))
280 return -ENXIO;
281 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
282 return -ENODEV;
283 if ((le16_to_cpu(btt_sb->version_major) != 2) ||
284 (le16_to_cpu(btt_sb->version_minor) != 0))
285 return -ENODEV;
286 } else {
287 /*
288 * Probe/setup for BTT v1.1 (NVDIMM_CCLASS_NONE or
289 * NVDIMM_CCLASS_BTT)
290 */
291 nd_btt->initial_offset = SZ_4K;
292 nd_btt->version_major = 1;
293 nd_btt->version_minor = 1;
294 if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb), 0))
295 return -ENXIO;
296 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
297 return -ENODEV;
298 if ((le16_to_cpu(btt_sb->version_major) != 1) ||
299 (le16_to_cpu(btt_sb->version_minor) != 1))
300 return -ENODEV;
301 }
302 return 0;
303 }
304 EXPORT_SYMBOL(nd_btt_version);
305
__nd_btt_probe(struct nd_btt * nd_btt,struct nd_namespace_common * ndns,struct btt_sb * btt_sb)306 static int __nd_btt_probe(struct nd_btt *nd_btt,
307 struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
308 {
309 int rc;
310
311 if (!btt_sb || !ndns || !nd_btt)
312 return -ENODEV;
313
314 if (nvdimm_namespace_capacity(ndns) < SZ_16M)
315 return -ENXIO;
316
317 rc = nd_btt_version(nd_btt, ndns, btt_sb);
318 if (rc < 0)
319 return rc;
320
321 nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
322 nd_btt->uuid = kmemdup(btt_sb->uuid, 16, GFP_KERNEL);
323 if (!nd_btt->uuid)
324 return -ENOMEM;
325
326 __nd_device_register(&nd_btt->dev);
327
328 return 0;
329 }
330
nd_btt_probe(struct device * dev,struct nd_namespace_common * ndns)331 int nd_btt_probe(struct device *dev, struct nd_namespace_common *ndns)
332 {
333 int rc;
334 struct device *btt_dev;
335 struct btt_sb *btt_sb;
336 struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
337
338 if (ndns->force_raw)
339 return -ENODEV;
340
341 switch (ndns->claim_class) {
342 case NVDIMM_CCLASS_NONE:
343 case NVDIMM_CCLASS_BTT:
344 case NVDIMM_CCLASS_BTT2:
345 break;
346 default:
347 return -ENODEV;
348 }
349
350 nvdimm_bus_lock(&ndns->dev);
351 btt_dev = __nd_btt_create(nd_region, 0, NULL, ndns);
352 nvdimm_bus_unlock(&ndns->dev);
353 if (!btt_dev)
354 return -ENOMEM;
355 btt_sb = devm_kzalloc(dev, sizeof(*btt_sb), GFP_KERNEL);
356 rc = __nd_btt_probe(to_nd_btt(btt_dev), ndns, btt_sb);
357 dev_dbg(dev, "btt: %s\n", rc == 0 ? dev_name(btt_dev) : "<none>");
358 if (rc < 0) {
359 struct nd_btt *nd_btt = to_nd_btt(btt_dev);
360
361 nd_detach_ndns(btt_dev, &nd_btt->ndns);
362 put_device(btt_dev);
363 }
364
365 return rc;
366 }
367 EXPORT_SYMBOL(nd_btt_probe);
368