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 "pfn.h" 22 #include "nd.h" 23 24 static void nd_pfn_release(struct device *dev) 25 { 26 struct nd_region *nd_region = to_nd_region(dev->parent); 27 struct nd_pfn *nd_pfn = to_nd_pfn(dev); 28 29 dev_dbg(dev, "%s\n", __func__); 30 nd_detach_ndns(&nd_pfn->dev, &nd_pfn->ndns); 31 ida_simple_remove(&nd_region->pfn_ida, nd_pfn->id); 32 kfree(nd_pfn->uuid); 33 kfree(nd_pfn); 34 } 35 36 static struct device_type nd_pfn_device_type = { 37 .name = "nd_pfn", 38 .release = nd_pfn_release, 39 }; 40 41 bool is_nd_pfn(struct device *dev) 42 { 43 return dev ? dev->type == &nd_pfn_device_type : false; 44 } 45 EXPORT_SYMBOL(is_nd_pfn); 46 47 struct nd_pfn *to_nd_pfn(struct device *dev) 48 { 49 struct nd_pfn *nd_pfn = container_of(dev, struct nd_pfn, dev); 50 51 WARN_ON(!is_nd_pfn(dev)); 52 return nd_pfn; 53 } 54 EXPORT_SYMBOL(to_nd_pfn); 55 56 static ssize_t mode_show(struct device *dev, 57 struct device_attribute *attr, char *buf) 58 { 59 struct nd_pfn *nd_pfn = to_nd_pfn(dev); 60 61 switch (nd_pfn->mode) { 62 case PFN_MODE_RAM: 63 return sprintf(buf, "ram\n"); 64 case PFN_MODE_PMEM: 65 return sprintf(buf, "pmem\n"); 66 default: 67 return sprintf(buf, "none\n"); 68 } 69 } 70 71 static ssize_t mode_store(struct device *dev, 72 struct device_attribute *attr, const char *buf, size_t len) 73 { 74 struct nd_pfn *nd_pfn = to_nd_pfn(dev); 75 ssize_t rc = 0; 76 77 device_lock(dev); 78 nvdimm_bus_lock(dev); 79 if (dev->driver) 80 rc = -EBUSY; 81 else { 82 size_t n = len - 1; 83 84 if (strncmp(buf, "pmem\n", n) == 0 85 || strncmp(buf, "pmem", n) == 0) { 86 /* TODO: allocate from PMEM support */ 87 rc = -ENOTTY; 88 } else if (strncmp(buf, "ram\n", n) == 0 89 || strncmp(buf, "ram", n) == 0) 90 nd_pfn->mode = PFN_MODE_RAM; 91 else if (strncmp(buf, "none\n", n) == 0 92 || strncmp(buf, "none", n) == 0) 93 nd_pfn->mode = PFN_MODE_NONE; 94 else 95 rc = -EINVAL; 96 } 97 dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__, 98 rc, buf, buf[len - 1] == '\n' ? "" : "\n"); 99 nvdimm_bus_unlock(dev); 100 device_unlock(dev); 101 102 return rc ? rc : len; 103 } 104 static DEVICE_ATTR_RW(mode); 105 106 static ssize_t uuid_show(struct device *dev, 107 struct device_attribute *attr, char *buf) 108 { 109 struct nd_pfn *nd_pfn = to_nd_pfn(dev); 110 111 if (nd_pfn->uuid) 112 return sprintf(buf, "%pUb\n", nd_pfn->uuid); 113 return sprintf(buf, "\n"); 114 } 115 116 static ssize_t uuid_store(struct device *dev, 117 struct device_attribute *attr, const char *buf, size_t len) 118 { 119 struct nd_pfn *nd_pfn = to_nd_pfn(dev); 120 ssize_t rc; 121 122 device_lock(dev); 123 rc = nd_uuid_store(dev, &nd_pfn->uuid, buf, len); 124 dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__, 125 rc, buf, buf[len - 1] == '\n' ? "" : "\n"); 126 device_unlock(dev); 127 128 return rc ? rc : len; 129 } 130 static DEVICE_ATTR_RW(uuid); 131 132 static ssize_t namespace_show(struct device *dev, 133 struct device_attribute *attr, char *buf) 134 { 135 struct nd_pfn *nd_pfn = to_nd_pfn(dev); 136 ssize_t rc; 137 138 nvdimm_bus_lock(dev); 139 rc = sprintf(buf, "%s\n", nd_pfn->ndns 140 ? dev_name(&nd_pfn->ndns->dev) : ""); 141 nvdimm_bus_unlock(dev); 142 return rc; 143 } 144 145 static ssize_t namespace_store(struct device *dev, 146 struct device_attribute *attr, const char *buf, size_t len) 147 { 148 struct nd_pfn *nd_pfn = to_nd_pfn(dev); 149 ssize_t rc; 150 151 device_lock(dev); 152 nvdimm_bus_lock(dev); 153 rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len); 154 dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__, 155 rc, buf, buf[len - 1] == '\n' ? "" : "\n"); 156 nvdimm_bus_unlock(dev); 157 device_unlock(dev); 158 159 return rc; 160 } 161 static DEVICE_ATTR_RW(namespace); 162 163 static struct attribute *nd_pfn_attributes[] = { 164 &dev_attr_mode.attr, 165 &dev_attr_namespace.attr, 166 &dev_attr_uuid.attr, 167 NULL, 168 }; 169 170 static struct attribute_group nd_pfn_attribute_group = { 171 .attrs = nd_pfn_attributes, 172 }; 173 174 static const struct attribute_group *nd_pfn_attribute_groups[] = { 175 &nd_pfn_attribute_group, 176 &nd_device_attribute_group, 177 &nd_numa_attribute_group, 178 NULL, 179 }; 180 181 static struct device *__nd_pfn_create(struct nd_region *nd_region, 182 u8 *uuid, enum nd_pfn_mode mode, 183 struct nd_namespace_common *ndns) 184 { 185 struct nd_pfn *nd_pfn; 186 struct device *dev; 187 188 /* we can only create pages for contiguous ranged of pmem */ 189 if (!is_nd_pmem(&nd_region->dev)) 190 return NULL; 191 192 nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL); 193 if (!nd_pfn) 194 return NULL; 195 196 nd_pfn->id = ida_simple_get(&nd_region->pfn_ida, 0, 0, GFP_KERNEL); 197 if (nd_pfn->id < 0) { 198 kfree(nd_pfn); 199 return NULL; 200 } 201 202 nd_pfn->mode = mode; 203 if (uuid) 204 uuid = kmemdup(uuid, 16, GFP_KERNEL); 205 nd_pfn->uuid = uuid; 206 dev = &nd_pfn->dev; 207 dev_set_name(dev, "pfn%d.%d", nd_region->id, nd_pfn->id); 208 dev->parent = &nd_region->dev; 209 dev->type = &nd_pfn_device_type; 210 dev->groups = nd_pfn_attribute_groups; 211 device_initialize(&nd_pfn->dev); 212 if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) { 213 dev_dbg(&ndns->dev, "%s failed, already claimed by %s\n", 214 __func__, dev_name(ndns->claim)); 215 put_device(dev); 216 return NULL; 217 } 218 return dev; 219 } 220 221 struct device *nd_pfn_create(struct nd_region *nd_region) 222 { 223 struct device *dev = __nd_pfn_create(nd_region, NULL, PFN_MODE_NONE, 224 NULL); 225 226 if (dev) 227 __nd_device_register(dev); 228 return dev; 229 } 230 231 int nd_pfn_validate(struct nd_pfn *nd_pfn) 232 { 233 struct nd_namespace_common *ndns = nd_pfn->ndns; 234 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 235 struct nd_namespace_io *nsio; 236 u64 checksum, offset; 237 238 if (!pfn_sb || !ndns) 239 return -ENODEV; 240 241 if (!is_nd_pmem(nd_pfn->dev.parent)) 242 return -ENODEV; 243 244 /* section alignment for simple hotplug */ 245 if (nvdimm_namespace_capacity(ndns) < ND_PFN_ALIGN) 246 return -ENODEV; 247 248 if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb))) 249 return -ENXIO; 250 251 if (memcmp(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN) != 0) 252 return -ENODEV; 253 254 checksum = le64_to_cpu(pfn_sb->checksum); 255 pfn_sb->checksum = 0; 256 if (checksum != nd_sb_checksum((struct nd_gen_sb *) pfn_sb)) 257 return -ENODEV; 258 pfn_sb->checksum = cpu_to_le64(checksum); 259 260 switch (le32_to_cpu(pfn_sb->mode)) { 261 case PFN_MODE_RAM: 262 break; 263 case PFN_MODE_PMEM: 264 /* TODO: allocate from PMEM support */ 265 return -ENOTTY; 266 default: 267 return -ENXIO; 268 } 269 270 if (!nd_pfn->uuid) { 271 /* from probe we allocate */ 272 nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL); 273 if (!nd_pfn->uuid) 274 return -ENOMEM; 275 } else { 276 /* from init we validate */ 277 if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0) 278 return -EINVAL; 279 } 280 281 /* 282 * These warnings are verbose because they can only trigger in 283 * the case where the physical address alignment of the 284 * namespace has changed since the pfn superblock was 285 * established. 286 */ 287 offset = le64_to_cpu(pfn_sb->dataoff); 288 nsio = to_nd_namespace_io(&ndns->dev); 289 if (nsio->res.start & ND_PFN_MASK) { 290 dev_err(&nd_pfn->dev, 291 "init failed: %s not section aligned\n", 292 dev_name(&ndns->dev)); 293 return -EBUSY; 294 } else if (offset >= resource_size(&nsio->res)) { 295 dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n", 296 dev_name(&ndns->dev)); 297 return -EBUSY; 298 } 299 300 return 0; 301 } 302 EXPORT_SYMBOL(nd_pfn_validate); 303 304 int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata) 305 { 306 int rc; 307 struct device *dev; 308 struct nd_pfn *nd_pfn; 309 struct nd_pfn_sb *pfn_sb; 310 struct nd_region *nd_region = to_nd_region(ndns->dev.parent); 311 312 if (ndns->force_raw) 313 return -ENODEV; 314 315 nvdimm_bus_lock(&ndns->dev); 316 dev = __nd_pfn_create(nd_region, NULL, PFN_MODE_NONE, ndns); 317 nvdimm_bus_unlock(&ndns->dev); 318 if (!dev) 319 return -ENOMEM; 320 dev_set_drvdata(dev, drvdata); 321 pfn_sb = kzalloc(sizeof(*pfn_sb), GFP_KERNEL); 322 nd_pfn = to_nd_pfn(dev); 323 nd_pfn->pfn_sb = pfn_sb; 324 rc = nd_pfn_validate(nd_pfn); 325 nd_pfn->pfn_sb = NULL; 326 kfree(pfn_sb); 327 dev_dbg(&ndns->dev, "%s: pfn: %s\n", __func__, 328 rc == 0 ? dev_name(dev) : "<none>"); 329 if (rc < 0) { 330 __nd_detach_ndns(dev, &nd_pfn->ndns); 331 put_device(dev); 332 } else 333 __nd_device_register(&nd_pfn->dev); 334 335 return rc; 336 } 337 EXPORT_SYMBOL(nd_pfn_probe); 338