1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved. 4 */ 5 #include <linux/device.h> 6 #include <linux/sizes.h> 7 #include "nd-core.h" 8 #include "pmem.h" 9 #include "pfn.h" 10 #include "btt.h" 11 #include "nd.h" 12 13 void __nd_detach_ndns(struct device *dev, struct nd_namespace_common **_ndns) 14 { 15 struct nd_namespace_common *ndns = *_ndns; 16 struct nvdimm_bus *nvdimm_bus; 17 18 if (!ndns) 19 return; 20 21 nvdimm_bus = walk_to_nvdimm_bus(&ndns->dev); 22 lockdep_assert_held(&nvdimm_bus->reconfig_mutex); 23 dev_WARN_ONCE(dev, ndns->claim != dev, "%s: invalid claim\n", __func__); 24 ndns->claim = NULL; 25 *_ndns = NULL; 26 put_device(&ndns->dev); 27 } 28 29 void nd_detach_ndns(struct device *dev, 30 struct nd_namespace_common **_ndns) 31 { 32 struct nd_namespace_common *ndns = *_ndns; 33 34 if (!ndns) 35 return; 36 get_device(&ndns->dev); 37 nvdimm_bus_lock(&ndns->dev); 38 __nd_detach_ndns(dev, _ndns); 39 nvdimm_bus_unlock(&ndns->dev); 40 put_device(&ndns->dev); 41 } 42 43 bool __nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach, 44 struct nd_namespace_common **_ndns) 45 { 46 struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&attach->dev); 47 48 if (attach->claim) 49 return false; 50 lockdep_assert_held(&nvdimm_bus->reconfig_mutex); 51 dev_WARN_ONCE(dev, *_ndns, "%s: invalid claim\n", __func__); 52 attach->claim = dev; 53 *_ndns = attach; 54 get_device(&attach->dev); 55 return true; 56 } 57 58 bool nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach, 59 struct nd_namespace_common **_ndns) 60 { 61 bool claimed; 62 63 nvdimm_bus_lock(&attach->dev); 64 claimed = __nd_attach_ndns(dev, attach, _ndns); 65 nvdimm_bus_unlock(&attach->dev); 66 return claimed; 67 } 68 69 static int namespace_match(struct device *dev, void *data) 70 { 71 char *name = data; 72 73 return strcmp(name, dev_name(dev)) == 0; 74 } 75 76 static bool is_idle(struct device *dev, struct nd_namespace_common *ndns) 77 { 78 struct nd_region *nd_region = to_nd_region(dev->parent); 79 struct device *seed = NULL; 80 81 if (is_nd_btt(dev)) 82 seed = nd_region->btt_seed; 83 else if (is_nd_pfn(dev)) 84 seed = nd_region->pfn_seed; 85 else if (is_nd_dax(dev)) 86 seed = nd_region->dax_seed; 87 88 if (seed == dev || ndns || dev->driver) 89 return false; 90 return true; 91 } 92 93 struct nd_pfn *to_nd_pfn_safe(struct device *dev) 94 { 95 /* 96 * pfn device attributes are re-used by dax device instances, so we 97 * need to be careful to correct device-to-nd_pfn conversion. 98 */ 99 if (is_nd_pfn(dev)) 100 return to_nd_pfn(dev); 101 102 if (is_nd_dax(dev)) { 103 struct nd_dax *nd_dax = to_nd_dax(dev); 104 105 return &nd_dax->nd_pfn; 106 } 107 108 WARN_ON(1); 109 return NULL; 110 } 111 112 static void nd_detach_and_reset(struct device *dev, 113 struct nd_namespace_common **_ndns) 114 { 115 /* detach the namespace and destroy / reset the device */ 116 __nd_detach_ndns(dev, _ndns); 117 if (is_idle(dev, *_ndns)) { 118 nd_device_unregister(dev, ND_ASYNC); 119 } else if (is_nd_btt(dev)) { 120 struct nd_btt *nd_btt = to_nd_btt(dev); 121 122 nd_btt->lbasize = 0; 123 kfree(nd_btt->uuid); 124 nd_btt->uuid = NULL; 125 } else if (is_nd_pfn(dev) || is_nd_dax(dev)) { 126 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 127 128 kfree(nd_pfn->uuid); 129 nd_pfn->uuid = NULL; 130 nd_pfn->mode = PFN_MODE_NONE; 131 } 132 } 133 134 ssize_t nd_namespace_store(struct device *dev, 135 struct nd_namespace_common **_ndns, const char *buf, 136 size_t len) 137 { 138 struct nd_namespace_common *ndns; 139 struct device *found; 140 char *name; 141 142 if (dev->driver) { 143 dev_dbg(dev, "namespace already active\n"); 144 return -EBUSY; 145 } 146 147 name = kstrndup(buf, len, GFP_KERNEL); 148 if (!name) 149 return -ENOMEM; 150 strim(name); 151 152 if (strncmp(name, "namespace", 9) == 0 || strcmp(name, "") == 0) 153 /* pass */; 154 else { 155 len = -EINVAL; 156 goto out; 157 } 158 159 ndns = *_ndns; 160 if (strcmp(name, "") == 0) { 161 nd_detach_and_reset(dev, _ndns); 162 goto out; 163 } else if (ndns) { 164 dev_dbg(dev, "namespace already set to: %s\n", 165 dev_name(&ndns->dev)); 166 len = -EBUSY; 167 goto out; 168 } 169 170 found = device_find_child(dev->parent, name, namespace_match); 171 if (!found) { 172 dev_dbg(dev, "'%s' not found under %s\n", name, 173 dev_name(dev->parent)); 174 len = -ENODEV; 175 goto out; 176 } 177 178 ndns = to_ndns(found); 179 180 switch (ndns->claim_class) { 181 case NVDIMM_CCLASS_NONE: 182 break; 183 case NVDIMM_CCLASS_BTT: 184 case NVDIMM_CCLASS_BTT2: 185 if (!is_nd_btt(dev)) { 186 len = -EBUSY; 187 goto out_attach; 188 } 189 break; 190 case NVDIMM_CCLASS_PFN: 191 if (!is_nd_pfn(dev)) { 192 len = -EBUSY; 193 goto out_attach; 194 } 195 break; 196 case NVDIMM_CCLASS_DAX: 197 if (!is_nd_dax(dev)) { 198 len = -EBUSY; 199 goto out_attach; 200 } 201 break; 202 default: 203 len = -EBUSY; 204 goto out_attach; 205 break; 206 } 207 208 if (__nvdimm_namespace_capacity(ndns) < SZ_16M) { 209 dev_dbg(dev, "%s too small to host\n", name); 210 len = -ENXIO; 211 goto out_attach; 212 } 213 214 WARN_ON_ONCE(!is_nvdimm_bus_locked(dev)); 215 if (!__nd_attach_ndns(dev, ndns, _ndns)) { 216 dev_dbg(dev, "%s already claimed\n", 217 dev_name(&ndns->dev)); 218 len = -EBUSY; 219 } 220 221 out_attach: 222 put_device(&ndns->dev); /* from device_find_child */ 223 out: 224 kfree(name); 225 return len; 226 } 227 228 /* 229 * nd_sb_checksum: compute checksum for a generic info block 230 * 231 * Returns a fletcher64 checksum of everything in the given info block 232 * except the last field (since that's where the checksum lives). 233 */ 234 u64 nd_sb_checksum(struct nd_gen_sb *nd_gen_sb) 235 { 236 u64 sum; 237 __le64 sum_save; 238 239 BUILD_BUG_ON(sizeof(struct btt_sb) != SZ_4K); 240 BUILD_BUG_ON(sizeof(struct nd_pfn_sb) != SZ_4K); 241 BUILD_BUG_ON(sizeof(struct nd_gen_sb) != SZ_4K); 242 243 sum_save = nd_gen_sb->checksum; 244 nd_gen_sb->checksum = 0; 245 sum = nd_fletcher64(nd_gen_sb, sizeof(*nd_gen_sb), 1); 246 nd_gen_sb->checksum = sum_save; 247 return sum; 248 } 249 EXPORT_SYMBOL(nd_sb_checksum); 250 251 static int nsio_rw_bytes(struct nd_namespace_common *ndns, 252 resource_size_t offset, void *buf, size_t size, int rw, 253 unsigned long flags) 254 { 255 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 256 unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512); 257 sector_t sector = offset >> 9; 258 int rc = 0, ret = 0; 259 260 if (unlikely(!size)) 261 return 0; 262 263 if (unlikely(offset + size > nsio->size)) { 264 dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n"); 265 return -EFAULT; 266 } 267 268 if (rw == READ) { 269 if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) 270 return -EIO; 271 if (memcpy_mcsafe(buf, nsio->addr + offset, size) != 0) 272 return -EIO; 273 return 0; 274 } 275 276 if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) { 277 if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512) 278 && !(flags & NVDIMM_IO_ATOMIC)) { 279 long cleared; 280 281 might_sleep(); 282 cleared = nvdimm_clear_poison(&ndns->dev, 283 nsio->res.start + offset, size); 284 if (cleared < size) 285 rc = -EIO; 286 if (cleared > 0 && cleared / 512) { 287 cleared /= 512; 288 badblocks_clear(&nsio->bb, sector, cleared); 289 } 290 arch_invalidate_pmem(nsio->addr + offset, size); 291 } else 292 rc = -EIO; 293 } 294 295 memcpy_flushcache(nsio->addr + offset, buf, size); 296 ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL); 297 if (ret) 298 rc = ret; 299 300 return rc; 301 } 302 303 int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio, 304 resource_size_t size) 305 { 306 struct resource *res = &nsio->res; 307 struct nd_namespace_common *ndns = &nsio->common; 308 309 nsio->size = size; 310 if (!devm_request_mem_region(dev, res->start, size, 311 dev_name(&ndns->dev))) { 312 dev_warn(dev, "could not reserve region %pR\n", res); 313 return -EBUSY; 314 } 315 316 ndns->rw_bytes = nsio_rw_bytes; 317 if (devm_init_badblocks(dev, &nsio->bb)) 318 return -ENOMEM; 319 nvdimm_badblocks_populate(to_nd_region(ndns->dev.parent), &nsio->bb, 320 &nsio->res); 321 322 nsio->addr = devm_memremap(dev, res->start, size, ARCH_MEMREMAP_PMEM); 323 324 return PTR_ERR_OR_ZERO(nsio->addr); 325 } 326 327 void devm_nsio_disable(struct device *dev, struct nd_namespace_io *nsio) 328 { 329 struct resource *res = &nsio->res; 330 331 devm_memunmap(dev, nsio->addr); 332 devm_exit_badblocks(dev, &nsio->bb); 333 devm_release_mem_region(dev, res->start, nsio->size); 334 } 335