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, "%s\n", __func__); 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_sector_size_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_sector_size_store(dev, buf, &nd_btt->lbasize, 76 btt_lbasize_supported); 77 dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__, 78 rc, buf, 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, "%s: result: %zd wrote: %s%s", __func__, 105 rc, buf, 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, "%s: result: %zd wrote: %s%s", __func__, 135 rc, buf, 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 struct attribute *nd_btt_attributes[] = { 144 &dev_attr_sector_size.attr, 145 &dev_attr_namespace.attr, 146 &dev_attr_uuid.attr, 147 NULL, 148 }; 149 150 static struct attribute_group nd_btt_attribute_group = { 151 .attrs = nd_btt_attributes, 152 }; 153 154 static const struct attribute_group *nd_btt_attribute_groups[] = { 155 &nd_btt_attribute_group, 156 &nd_device_attribute_group, 157 &nd_numa_attribute_group, 158 NULL, 159 }; 160 161 static struct device *__nd_btt_create(struct nd_region *nd_region, 162 unsigned long lbasize, u8 *uuid, 163 struct nd_namespace_common *ndns) 164 { 165 struct nd_btt *nd_btt; 166 struct device *dev; 167 168 nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL); 169 if (!nd_btt) 170 return NULL; 171 172 nd_btt->id = ida_simple_get(&nd_region->btt_ida, 0, 0, GFP_KERNEL); 173 if (nd_btt->id < 0) { 174 kfree(nd_btt); 175 return NULL; 176 } 177 178 nd_btt->lbasize = lbasize; 179 if (uuid) 180 uuid = kmemdup(uuid, 16, GFP_KERNEL); 181 nd_btt->uuid = uuid; 182 dev = &nd_btt->dev; 183 dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id); 184 dev->parent = &nd_region->dev; 185 dev->type = &nd_btt_device_type; 186 dev->groups = nd_btt_attribute_groups; 187 device_initialize(&nd_btt->dev); 188 if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) { 189 dev_dbg(&ndns->dev, "%s failed, already claimed by %s\n", 190 __func__, dev_name(ndns->claim)); 191 put_device(dev); 192 return NULL; 193 } 194 return dev; 195 } 196 197 struct device *nd_btt_create(struct nd_region *nd_region) 198 { 199 struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL); 200 201 if (dev) 202 __nd_device_register(dev); 203 return dev; 204 } 205 206 static bool uuid_is_null(u8 *uuid) 207 { 208 static const u8 null_uuid[16]; 209 210 return (memcmp(uuid, null_uuid, 16) == 0); 211 } 212 213 /** 214 * nd_btt_arena_is_valid - check if the metadata layout is valid 215 * @nd_btt: device with BTT geometry and backing device info 216 * @super: pointer to the arena's info block being tested 217 * 218 * Check consistency of the btt info block with itself by validating 219 * the checksum, and with the parent namespace by verifying the 220 * parent_uuid contained in the info block with the one supplied in. 221 * 222 * Returns: 223 * false for an invalid info block, true for a valid one 224 */ 225 bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super) 226 { 227 const u8 *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev); 228 u64 checksum; 229 230 if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0) 231 return false; 232 233 if (!uuid_is_null(super->parent_uuid)) 234 if (memcmp(super->parent_uuid, parent_uuid, 16) != 0) 235 return false; 236 237 checksum = le64_to_cpu(super->checksum); 238 super->checksum = 0; 239 if (checksum != nd_sb_checksum((struct nd_gen_sb *) super)) 240 return false; 241 super->checksum = cpu_to_le64(checksum); 242 243 /* TODO: figure out action for this */ 244 if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0) 245 dev_info(&nd_btt->dev, "Found arena with an error flag\n"); 246 247 return true; 248 } 249 EXPORT_SYMBOL(nd_btt_arena_is_valid); 250 251 static int __nd_btt_probe(struct nd_btt *nd_btt, 252 struct nd_namespace_common *ndns, struct btt_sb *btt_sb) 253 { 254 if (!btt_sb || !ndns || !nd_btt) 255 return -ENODEV; 256 257 if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb))) 258 return -ENXIO; 259 260 if (nvdimm_namespace_capacity(ndns) < SZ_16M) 261 return -ENXIO; 262 263 if (!nd_btt_arena_is_valid(nd_btt, btt_sb)) 264 return -ENODEV; 265 266 nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize); 267 nd_btt->uuid = kmemdup(btt_sb->uuid, 16, GFP_KERNEL); 268 if (!nd_btt->uuid) 269 return -ENOMEM; 270 271 __nd_device_register(&nd_btt->dev); 272 273 return 0; 274 } 275 276 int nd_btt_probe(struct nd_namespace_common *ndns, void *drvdata) 277 { 278 int rc; 279 struct device *dev; 280 struct btt_sb *btt_sb; 281 struct nd_region *nd_region = to_nd_region(ndns->dev.parent); 282 283 if (ndns->force_raw) 284 return -ENODEV; 285 286 nvdimm_bus_lock(&ndns->dev); 287 dev = __nd_btt_create(nd_region, 0, NULL, ndns); 288 nvdimm_bus_unlock(&ndns->dev); 289 if (!dev) 290 return -ENOMEM; 291 dev_set_drvdata(dev, drvdata); 292 btt_sb = kzalloc(sizeof(*btt_sb), GFP_KERNEL); 293 rc = __nd_btt_probe(to_nd_btt(dev), ndns, btt_sb); 294 kfree(btt_sb); 295 dev_dbg(&ndns->dev, "%s: btt: %s\n", __func__, 296 rc == 0 ? dev_name(dev) : "<none>"); 297 if (rc < 0) { 298 struct nd_btt *nd_btt = to_nd_btt(dev); 299 300 __nd_detach_ndns(dev, &nd_btt->ndns); 301 put_device(dev); 302 } 303 304 return rc; 305 } 306 EXPORT_SYMBOL(nd_btt_probe); 307