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