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 #include <linux/blkdev.h> 14 #include <linux/device.h> 15 #include <linux/genhd.h> 16 #include <linux/sizes.h> 17 #include <linux/slab.h> 18 #include <linux/fs.h> 19 #include <linux/mm.h> 20 #include "nd-core.h" 21 #include "btt.h" 22 #include "nd.h" 23 24 static void nd_btt_release(struct device *dev) 25 { 26 struct nd_region *nd_region = to_nd_region(dev->parent); 27 struct nd_btt *nd_btt = to_nd_btt(dev); 28 29 dev_dbg(dev, "trace\n"); 30 nd_detach_ndns(&nd_btt->dev, &nd_btt->ndns); 31 ida_simple_remove(&nd_region->btt_ida, nd_btt->id); 32 kfree(nd_btt->uuid); 33 kfree(nd_btt); 34 } 35 36 static struct device_type nd_btt_device_type = { 37 .name = "nd_btt", 38 .release = nd_btt_release, 39 }; 40 41 bool is_nd_btt(struct device *dev) 42 { 43 return dev->type == &nd_btt_device_type; 44 } 45 EXPORT_SYMBOL(is_nd_btt); 46 47 struct nd_btt *to_nd_btt(struct device *dev) 48 { 49 struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev); 50 51 WARN_ON(!is_nd_btt(dev)); 52 return nd_btt; 53 } 54 EXPORT_SYMBOL(to_nd_btt); 55 56 static const unsigned long btt_lbasize_supported[] = { 512, 520, 528, 57 4096, 4104, 4160, 4224, 0 }; 58 59 static ssize_t sector_size_show(struct device *dev, 60 struct device_attribute *attr, char *buf) 61 { 62 struct nd_btt *nd_btt = to_nd_btt(dev); 63 64 return nd_size_select_show(nd_btt->lbasize, btt_lbasize_supported, buf); 65 } 66 67 static ssize_t sector_size_store(struct device *dev, 68 struct device_attribute *attr, const char *buf, size_t len) 69 { 70 struct nd_btt *nd_btt = to_nd_btt(dev); 71 ssize_t rc; 72 73 device_lock(dev); 74 nvdimm_bus_lock(dev); 75 rc = nd_size_select_store(dev, buf, &nd_btt->lbasize, 76 btt_lbasize_supported); 77 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 78 buf[len - 1] == '\n' ? "" : "\n"); 79 nvdimm_bus_unlock(dev); 80 device_unlock(dev); 81 82 return rc ? rc : len; 83 } 84 static DEVICE_ATTR_RW(sector_size); 85 86 static ssize_t uuid_show(struct device *dev, 87 struct device_attribute *attr, char *buf) 88 { 89 struct nd_btt *nd_btt = to_nd_btt(dev); 90 91 if (nd_btt->uuid) 92 return sprintf(buf, "%pUb\n", nd_btt->uuid); 93 return sprintf(buf, "\n"); 94 } 95 96 static ssize_t uuid_store(struct device *dev, 97 struct device_attribute *attr, const char *buf, size_t len) 98 { 99 struct nd_btt *nd_btt = to_nd_btt(dev); 100 ssize_t rc; 101 102 device_lock(dev); 103 rc = nd_uuid_store(dev, &nd_btt->uuid, buf, len); 104 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 105 buf[len - 1] == '\n' ? "" : "\n"); 106 device_unlock(dev); 107 108 return rc ? rc : len; 109 } 110 static DEVICE_ATTR_RW(uuid); 111 112 static ssize_t namespace_show(struct device *dev, 113 struct device_attribute *attr, char *buf) 114 { 115 struct nd_btt *nd_btt = to_nd_btt(dev); 116 ssize_t rc; 117 118 nvdimm_bus_lock(dev); 119 rc = sprintf(buf, "%s\n", nd_btt->ndns 120 ? dev_name(&nd_btt->ndns->dev) : ""); 121 nvdimm_bus_unlock(dev); 122 return rc; 123 } 124 125 static ssize_t namespace_store(struct device *dev, 126 struct device_attribute *attr, const char *buf, size_t len) 127 { 128 struct nd_btt *nd_btt = to_nd_btt(dev); 129 ssize_t rc; 130 131 device_lock(dev); 132 nvdimm_bus_lock(dev); 133 rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len); 134 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 135 buf[len - 1] == '\n' ? "" : "\n"); 136 nvdimm_bus_unlock(dev); 137 device_unlock(dev); 138 139 return rc; 140 } 141 static DEVICE_ATTR_RW(namespace); 142 143 static ssize_t size_show(struct device *dev, 144 struct device_attribute *attr, char *buf) 145 { 146 struct nd_btt *nd_btt = to_nd_btt(dev); 147 ssize_t rc; 148 149 device_lock(dev); 150 if (dev->driver) 151 rc = sprintf(buf, "%llu\n", nd_btt->size); 152 else { 153 /* no size to convey if the btt instance is disabled */ 154 rc = -ENXIO; 155 } 156 device_unlock(dev); 157 158 return rc; 159 } 160 static DEVICE_ATTR_RO(size); 161 162 static ssize_t log_zero_flags_show(struct device *dev, 163 struct device_attribute *attr, char *buf) 164 { 165 return sprintf(buf, "Y\n"); 166 } 167 static DEVICE_ATTR_RO(log_zero_flags); 168 169 static struct attribute *nd_btt_attributes[] = { 170 &dev_attr_sector_size.attr, 171 &dev_attr_namespace.attr, 172 &dev_attr_uuid.attr, 173 &dev_attr_size.attr, 174 &dev_attr_log_zero_flags.attr, 175 NULL, 176 }; 177 178 static struct attribute_group nd_btt_attribute_group = { 179 .attrs = nd_btt_attributes, 180 }; 181 182 static const struct attribute_group *nd_btt_attribute_groups[] = { 183 &nd_btt_attribute_group, 184 &nd_device_attribute_group, 185 &nd_numa_attribute_group, 186 NULL, 187 }; 188 189 static struct device *__nd_btt_create(struct nd_region *nd_region, 190 unsigned long lbasize, u8 *uuid, 191 struct nd_namespace_common *ndns) 192 { 193 struct nd_btt *nd_btt; 194 struct device *dev; 195 196 nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL); 197 if (!nd_btt) 198 return NULL; 199 200 nd_btt->id = ida_simple_get(&nd_region->btt_ida, 0, 0, GFP_KERNEL); 201 if (nd_btt->id < 0) 202 goto out_nd_btt; 203 204 nd_btt->lbasize = lbasize; 205 if (uuid) { 206 uuid = kmemdup(uuid, 16, GFP_KERNEL); 207 if (!uuid) 208 goto out_put_id; 209 } 210 nd_btt->uuid = uuid; 211 dev = &nd_btt->dev; 212 dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id); 213 dev->parent = &nd_region->dev; 214 dev->type = &nd_btt_device_type; 215 dev->groups = nd_btt_attribute_groups; 216 device_initialize(&nd_btt->dev); 217 if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) { 218 dev_dbg(&ndns->dev, "failed, already claimed by %s\n", 219 dev_name(ndns->claim)); 220 put_device(dev); 221 return NULL; 222 } 223 return dev; 224 225 out_put_id: 226 ida_simple_remove(&nd_region->btt_ida, nd_btt->id); 227 228 out_nd_btt: 229 kfree(nd_btt); 230 return NULL; 231 } 232 233 struct device *nd_btt_create(struct nd_region *nd_region) 234 { 235 struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL); 236 237 __nd_device_register(dev); 238 return dev; 239 } 240 241 /** 242 * nd_btt_arena_is_valid - check if the metadata layout is valid 243 * @nd_btt: device with BTT geometry and backing device info 244 * @super: pointer to the arena's info block being tested 245 * 246 * Check consistency of the btt info block with itself by validating 247 * the checksum, and with the parent namespace by verifying the 248 * parent_uuid contained in the info block with the one supplied in. 249 * 250 * Returns: 251 * false for an invalid info block, true for a valid one 252 */ 253 bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super) 254 { 255 const u8 *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev); 256 u64 checksum; 257 258 if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0) 259 return false; 260 261 if (!guid_is_null((guid_t *)&super->parent_uuid)) 262 if (memcmp(super->parent_uuid, parent_uuid, 16) != 0) 263 return false; 264 265 checksum = le64_to_cpu(super->checksum); 266 super->checksum = 0; 267 if (checksum != nd_sb_checksum((struct nd_gen_sb *) super)) 268 return false; 269 super->checksum = cpu_to_le64(checksum); 270 271 /* TODO: figure out action for this */ 272 if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0) 273 dev_info(&nd_btt->dev, "Found arena with an error flag\n"); 274 275 return true; 276 } 277 EXPORT_SYMBOL(nd_btt_arena_is_valid); 278 279 int nd_btt_version(struct nd_btt *nd_btt, struct nd_namespace_common *ndns, 280 struct btt_sb *btt_sb) 281 { 282 if (ndns->claim_class == NVDIMM_CCLASS_BTT2) { 283 /* Probe/setup for BTT v2.0 */ 284 nd_btt->initial_offset = 0; 285 nd_btt->version_major = 2; 286 nd_btt->version_minor = 0; 287 if (nvdimm_read_bytes(ndns, 0, btt_sb, sizeof(*btt_sb), 0)) 288 return -ENXIO; 289 if (!nd_btt_arena_is_valid(nd_btt, btt_sb)) 290 return -ENODEV; 291 if ((le16_to_cpu(btt_sb->version_major) != 2) || 292 (le16_to_cpu(btt_sb->version_minor) != 0)) 293 return -ENODEV; 294 } else { 295 /* 296 * Probe/setup for BTT v1.1 (NVDIMM_CCLASS_NONE or 297 * NVDIMM_CCLASS_BTT) 298 */ 299 nd_btt->initial_offset = SZ_4K; 300 nd_btt->version_major = 1; 301 nd_btt->version_minor = 1; 302 if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb), 0)) 303 return -ENXIO; 304 if (!nd_btt_arena_is_valid(nd_btt, btt_sb)) 305 return -ENODEV; 306 if ((le16_to_cpu(btt_sb->version_major) != 1) || 307 (le16_to_cpu(btt_sb->version_minor) != 1)) 308 return -ENODEV; 309 } 310 return 0; 311 } 312 EXPORT_SYMBOL(nd_btt_version); 313 314 static int __nd_btt_probe(struct nd_btt *nd_btt, 315 struct nd_namespace_common *ndns, struct btt_sb *btt_sb) 316 { 317 int rc; 318 319 if (!btt_sb || !ndns || !nd_btt) 320 return -ENODEV; 321 322 if (nvdimm_namespace_capacity(ndns) < SZ_16M) 323 return -ENXIO; 324 325 rc = nd_btt_version(nd_btt, ndns, btt_sb); 326 if (rc < 0) 327 return rc; 328 329 nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize); 330 nd_btt->uuid = kmemdup(btt_sb->uuid, 16, GFP_KERNEL); 331 if (!nd_btt->uuid) 332 return -ENOMEM; 333 334 __nd_device_register(&nd_btt->dev); 335 336 return 0; 337 } 338 339 int nd_btt_probe(struct device *dev, struct nd_namespace_common *ndns) 340 { 341 int rc; 342 struct device *btt_dev; 343 struct btt_sb *btt_sb; 344 struct nd_region *nd_region = to_nd_region(ndns->dev.parent); 345 346 if (ndns->force_raw) 347 return -ENODEV; 348 349 switch (ndns->claim_class) { 350 case NVDIMM_CCLASS_NONE: 351 case NVDIMM_CCLASS_BTT: 352 case NVDIMM_CCLASS_BTT2: 353 break; 354 default: 355 return -ENODEV; 356 } 357 358 nvdimm_bus_lock(&ndns->dev); 359 btt_dev = __nd_btt_create(nd_region, 0, NULL, ndns); 360 nvdimm_bus_unlock(&ndns->dev); 361 if (!btt_dev) 362 return -ENOMEM; 363 btt_sb = devm_kzalloc(dev, sizeof(*btt_sb), GFP_KERNEL); 364 rc = __nd_btt_probe(to_nd_btt(btt_dev), ndns, btt_sb); 365 dev_dbg(dev, "btt: %s\n", rc == 0 ? dev_name(btt_dev) : "<none>"); 366 if (rc < 0) { 367 struct nd_btt *nd_btt = to_nd_btt(btt_dev); 368 369 nd_detach_ndns(btt_dev, &nd_btt->ndns); 370 put_device(btt_dev); 371 } 372 373 return rc; 374 } 375 EXPORT_SYMBOL(nd_btt_probe); 376