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