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 <linux/badblocks.h> 8 #include "nd-core.h" 9 #include "pmem.h" 10 #include "pfn.h" 11 #include "btt.h" 12 #include "nd.h" 13 14 void __nd_detach_ndns(struct device *dev, struct nd_namespace_common **_ndns) 15 { 16 struct nd_namespace_common *ndns = *_ndns; 17 struct nvdimm_bus *nvdimm_bus; 18 19 if (!ndns) 20 return; 21 22 nvdimm_bus = walk_to_nvdimm_bus(&ndns->dev); 23 lockdep_assert_held(&nvdimm_bus->reconfig_mutex); 24 dev_WARN_ONCE(dev, ndns->claim != dev, "%s: invalid claim\n", __func__); 25 ndns->claim = NULL; 26 *_ndns = NULL; 27 put_device(&ndns->dev); 28 } 29 30 void nd_detach_ndns(struct device *dev, 31 struct nd_namespace_common **_ndns) 32 { 33 struct nd_namespace_common *ndns = *_ndns; 34 35 if (!ndns) 36 return; 37 get_device(&ndns->dev); 38 nvdimm_bus_lock(&ndns->dev); 39 __nd_detach_ndns(dev, _ndns); 40 nvdimm_bus_unlock(&ndns->dev); 41 put_device(&ndns->dev); 42 } 43 44 bool __nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach, 45 struct nd_namespace_common **_ndns) 46 { 47 struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&attach->dev); 48 49 if (attach->claim) 50 return false; 51 lockdep_assert_held(&nvdimm_bus->reconfig_mutex); 52 dev_WARN_ONCE(dev, *_ndns, "%s: invalid claim\n", __func__); 53 attach->claim = dev; 54 *_ndns = attach; 55 get_device(&attach->dev); 56 return true; 57 } 58 59 bool nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach, 60 struct nd_namespace_common **_ndns) 61 { 62 bool claimed; 63 64 nvdimm_bus_lock(&attach->dev); 65 claimed = __nd_attach_ndns(dev, attach, _ndns); 66 nvdimm_bus_unlock(&attach->dev); 67 return claimed; 68 } 69 70 static int namespace_match(struct device *dev, void *data) 71 { 72 char *name = data; 73 74 return strcmp(name, dev_name(dev)) == 0; 75 } 76 77 static bool is_idle(struct device *dev, struct nd_namespace_common *ndns) 78 { 79 struct nd_region *nd_region = to_nd_region(dev->parent); 80 struct device *seed = NULL; 81 82 if (is_nd_btt(dev)) 83 seed = nd_region->btt_seed; 84 else if (is_nd_pfn(dev)) 85 seed = nd_region->pfn_seed; 86 else if (is_nd_dax(dev)) 87 seed = nd_region->dax_seed; 88 89 if (seed == dev || ndns || dev->driver) 90 return false; 91 return true; 92 } 93 94 struct nd_pfn *to_nd_pfn_safe(struct device *dev) 95 { 96 /* 97 * pfn device attributes are re-used by dax device instances, so we 98 * need to be careful to correct device-to-nd_pfn conversion. 99 */ 100 if (is_nd_pfn(dev)) 101 return to_nd_pfn(dev); 102 103 if (is_nd_dax(dev)) { 104 struct nd_dax *nd_dax = to_nd_dax(dev); 105 106 return &nd_dax->nd_pfn; 107 } 108 109 WARN_ON(1); 110 return NULL; 111 } 112 113 static void nd_detach_and_reset(struct device *dev, 114 struct nd_namespace_common **_ndns) 115 { 116 /* detach the namespace and destroy / reset the device */ 117 __nd_detach_ndns(dev, _ndns); 118 if (is_idle(dev, *_ndns)) { 119 nd_device_unregister(dev, ND_ASYNC); 120 } else if (is_nd_btt(dev)) { 121 struct nd_btt *nd_btt = to_nd_btt(dev); 122 123 nd_btt->lbasize = 0; 124 kfree(nd_btt->uuid); 125 nd_btt->uuid = NULL; 126 } else if (is_nd_pfn(dev) || is_nd_dax(dev)) { 127 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 128 129 kfree(nd_pfn->uuid); 130 nd_pfn->uuid = NULL; 131 nd_pfn->mode = PFN_MODE_NONE; 132 } 133 } 134 135 ssize_t nd_namespace_store(struct device *dev, 136 struct nd_namespace_common **_ndns, const char *buf, 137 size_t len) 138 { 139 struct nd_namespace_common *ndns; 140 struct device *found; 141 char *name; 142 143 if (dev->driver) { 144 dev_dbg(dev, "namespace already active\n"); 145 return -EBUSY; 146 } 147 148 name = kstrndup(buf, len, GFP_KERNEL); 149 if (!name) 150 return -ENOMEM; 151 strim(name); 152 153 if (strncmp(name, "namespace", 9) == 0 || strcmp(name, "") == 0) 154 /* pass */; 155 else { 156 len = -EINVAL; 157 goto out; 158 } 159 160 ndns = *_ndns; 161 if (strcmp(name, "") == 0) { 162 nd_detach_and_reset(dev, _ndns); 163 goto out; 164 } else if (ndns) { 165 dev_dbg(dev, "namespace already set to: %s\n", 166 dev_name(&ndns->dev)); 167 len = -EBUSY; 168 goto out; 169 } 170 171 found = device_find_child(dev->parent, name, namespace_match); 172 if (!found) { 173 dev_dbg(dev, "'%s' not found under %s\n", name, 174 dev_name(dev->parent)); 175 len = -ENODEV; 176 goto out; 177 } 178 179 ndns = to_ndns(found); 180 181 switch (ndns->claim_class) { 182 case NVDIMM_CCLASS_NONE: 183 break; 184 case NVDIMM_CCLASS_BTT: 185 case NVDIMM_CCLASS_BTT2: 186 if (!is_nd_btt(dev)) { 187 len = -EBUSY; 188 goto out_attach; 189 } 190 break; 191 case NVDIMM_CCLASS_PFN: 192 if (!is_nd_pfn(dev)) { 193 len = -EBUSY; 194 goto out_attach; 195 } 196 break; 197 case NVDIMM_CCLASS_DAX: 198 if (!is_nd_dax(dev)) { 199 len = -EBUSY; 200 goto out_attach; 201 } 202 break; 203 default: 204 len = -EBUSY; 205 goto out_attach; 206 break; 207 } 208 209 if (__nvdimm_namespace_capacity(ndns) < SZ_16M) { 210 dev_dbg(dev, "%s too small to host\n", name); 211 len = -ENXIO; 212 goto out_attach; 213 } 214 215 WARN_ON_ONCE(!is_nvdimm_bus_locked(dev)); 216 if (!__nd_attach_ndns(dev, ndns, _ndns)) { 217 dev_dbg(dev, "%s already claimed\n", 218 dev_name(&ndns->dev)); 219 len = -EBUSY; 220 } 221 222 out_attach: 223 put_device(&ndns->dev); /* from device_find_child */ 224 out: 225 kfree(name); 226 return len; 227 } 228 229 /* 230 * nd_sb_checksum: compute checksum for a generic info block 231 * 232 * Returns a fletcher64 checksum of everything in the given info block 233 * except the last field (since that's where the checksum lives). 234 */ 235 u64 nd_sb_checksum(struct nd_gen_sb *nd_gen_sb) 236 { 237 u64 sum; 238 __le64 sum_save; 239 240 BUILD_BUG_ON(sizeof(struct btt_sb) != SZ_4K); 241 BUILD_BUG_ON(sizeof(struct nd_pfn_sb) != SZ_4K); 242 BUILD_BUG_ON(sizeof(struct nd_gen_sb) != SZ_4K); 243 244 sum_save = nd_gen_sb->checksum; 245 nd_gen_sb->checksum = 0; 246 sum = nd_fletcher64(nd_gen_sb, sizeof(*nd_gen_sb), 1); 247 nd_gen_sb->checksum = sum_save; 248 return sum; 249 } 250 EXPORT_SYMBOL(nd_sb_checksum); 251 252 static int nsio_rw_bytes(struct nd_namespace_common *ndns, 253 resource_size_t offset, void *buf, size_t size, int rw, 254 unsigned long flags) 255 { 256 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 257 unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512); 258 sector_t sector = offset >> 9; 259 int rc = 0, ret = 0; 260 261 if (unlikely(!size)) 262 return 0; 263 264 if (unlikely(offset + size > nsio->size)) { 265 dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n"); 266 return -EFAULT; 267 } 268 269 if (rw == READ) { 270 if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) 271 return -EIO; 272 if (copy_mc_to_kernel(buf, nsio->addr + offset, size) != 0) 273 return -EIO; 274 return 0; 275 } 276 277 if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) { 278 if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512) 279 && !(flags & NVDIMM_IO_ATOMIC)) { 280 long cleared; 281 282 might_sleep(); 283 cleared = nvdimm_clear_poison(&ndns->dev, 284 nsio->res.start + offset, size); 285 if (cleared < size) 286 rc = -EIO; 287 if (cleared > 0 && cleared / 512) { 288 cleared /= 512; 289 badblocks_clear(&nsio->bb, sector, cleared); 290 } 291 arch_invalidate_pmem(nsio->addr + offset, size); 292 } else 293 rc = -EIO; 294 } 295 296 memcpy_flushcache(nsio->addr + offset, buf, size); 297 ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL); 298 if (ret) 299 rc = ret; 300 301 return rc; 302 } 303 304 int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio, 305 resource_size_t size) 306 { 307 struct nd_namespace_common *ndns = &nsio->common; 308 struct range range = { 309 .start = nsio->res.start, 310 .end = nsio->res.end, 311 }; 312 313 nsio->size = size; 314 if (!devm_request_mem_region(dev, range.start, size, 315 dev_name(&ndns->dev))) { 316 dev_warn(dev, "could not reserve region %pR\n", &nsio->res); 317 return -EBUSY; 318 } 319 320 ndns->rw_bytes = nsio_rw_bytes; 321 if (devm_init_badblocks(dev, &nsio->bb)) 322 return -ENOMEM; 323 nvdimm_badblocks_populate(to_nd_region(ndns->dev.parent), &nsio->bb, 324 &range); 325 326 nsio->addr = devm_memremap(dev, range.start, size, ARCH_MEMREMAP_PMEM); 327 328 return PTR_ERR_OR_ZERO(nsio->addr); 329 } 330 331 void devm_nsio_disable(struct device *dev, struct nd_namespace_io *nsio) 332 { 333 struct resource *res = &nsio->res; 334 335 devm_memunmap(dev, nsio->addr); 336 devm_exit_badblocks(dev, &nsio->bb); 337 devm_release_mem_region(dev, res->start, nsio->size); 338 } 339