drivers/nvdimm/dimm_devs.c

   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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14 #include <linux/vmalloc.h>
  15 #include <linux/device.h>
  16 #include <linux/ndctl.h>
  17 #include <linux/slab.h>
  18 #include <linux/io.h>
  19 #include <linux/fs.h>
  20 #include <linux/mm.h>
  21 #include "nd-core.h"
  22 #include "nd.h"
  23
  24 static DEFINE_IDA(dimm_ida);
  25
  26 /*
  27  * Retrieve bus and dimm handle and return if this bus supports
  28  * get_config_data commands
  29  */
  30 static int __validate_dimm(struct nvdimm_drvdata *ndd)
  31 {
  32         struct nvdimm *nvdimm;
  33
  34         if (!ndd)
  35                 return -EINVAL;
  36
  37         nvdimm = to_nvdimm(ndd->dev);
  38
  39         if (!nvdimm->dsm_mask)
  40                 return -ENXIO;
  41         if (!test_bit(ND_CMD_GET_CONFIG_DATA, nvdimm->dsm_mask))
  42                 return -ENXIO;
  43
  44         return 0;
  45 }
  46
  47 static int validate_dimm(struct nvdimm_drvdata *ndd)
  48 {
  49         int rc = __validate_dimm(ndd);
  50
  51         if (rc && ndd)
  52                 dev_dbg(ndd->dev, "%pf: %s error: %d\n",
  53                                 __builtin_return_address(0), __func__, rc);
  54         return rc;
  55 }
  56
  57 /**
  58  * nvdimm_init_nsarea - determine the geometry of a dimm's namespace area
  59  * @nvdimm: dimm to initialize
  60  */
  61 int nvdimm_init_nsarea(struct nvdimm_drvdata *ndd)
  62 {
  63         struct nd_cmd_get_config_size *cmd = &ndd->nsarea;
  64         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
  65         struct nvdimm_bus_descriptor *nd_desc;
  66         int rc = validate_dimm(ndd);
  67
  68         if (rc)
  69                 return rc;
  70
  71         if (cmd->config_size)
  72                 return 0; /* already valid */
  73
  74         memset(cmd, 0, sizeof(*cmd));
  75         nd_desc = nvdimm_bus->nd_desc;
  76         return nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
  77                         ND_CMD_GET_CONFIG_SIZE, cmd, sizeof(*cmd));
  78 }
  79
  80 int nvdimm_init_config_data(struct nvdimm_drvdata *ndd)
  81 {
  82         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
  83         struct nd_cmd_get_config_data_hdr *cmd;
  84         struct nvdimm_bus_descriptor *nd_desc;
  85         int rc = validate_dimm(ndd);
  86         u32 max_cmd_size, config_size;
  87         size_t offset;
  88
  89         if (rc)
  90                 return rc;
  91
  92         if (ndd->data)
  93                 return 0;
  94
  95         if (ndd->nsarea.status || ndd->nsarea.max_xfer == 0
  96                         || ndd->nsarea.config_size < ND_LABEL_MIN_SIZE) {
  97                 dev_dbg(ndd->dev, "failed to init config data area: (%d:%d)\n",
  98                                 ndd->nsarea.max_xfer, ndd->nsarea.config_size);
  99                 return -ENXIO;
 100         }
 101
 102         ndd->data = kmalloc(ndd->nsarea.config_size, GFP_KERNEL);
 103         if (!ndd->data)
 104                 ndd->data = vmalloc(ndd->nsarea.config_size);
 105
 106         if (!ndd->data)
 107                 return -ENOMEM;
 108
 109         max_cmd_size = min_t(u32, PAGE_SIZE, ndd->nsarea.max_xfer);
 110         cmd = kzalloc(max_cmd_size + sizeof(*cmd), GFP_KERNEL);
 111         if (!cmd)
 112                 return -ENOMEM;
 113
 114         nd_desc = nvdimm_bus->nd_desc;
 115         for (config_size = ndd->nsarea.config_size, offset = 0;
 116                         config_size; config_size -= cmd->in_length,
 117                         offset += cmd->in_length) {
 118                 cmd->in_length = min(config_size, max_cmd_size);
 119                 cmd->in_offset = offset;
 120                 rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
 121                                 ND_CMD_GET_CONFIG_DATA, cmd,
 122                                 cmd->in_length + sizeof(*cmd));
 123                 if (rc || cmd->status) {
 124                         rc = -ENXIO;
 125                         break;
 126                 }
 127                 memcpy(ndd->data + offset, cmd->out_buf, cmd->in_length);
 128         }
 129         dev_dbg(ndd->dev, "%s: len: %zu rc: %d\n", __func__, offset, rc);
 130         kfree(cmd);
 131
 132         return rc;
 133 }
 134
 135 static void nvdimm_release(struct device *dev)
 136 {
 137         struct nvdimm *nvdimm = to_nvdimm(dev);
 138
 139         ida_simple_remove(&dimm_ida, nvdimm->id);
 140         kfree(nvdimm);
 141 }
 142
 143 static struct device_type nvdimm_device_type = {
 144         .name = "nvdimm",
 145         .release = nvdimm_release,
 146 };
 147
 148 bool is_nvdimm(struct device *dev)
 149 {
 150         return dev->type == &nvdimm_device_type;
 151 }
 152
 153 struct nvdimm *to_nvdimm(struct device *dev)
 154 {
 155         struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);
 156
 157         WARN_ON(!is_nvdimm(dev));
 158         return nvdimm;
 159 }
 160 EXPORT_SYMBOL_GPL(to_nvdimm);
 161
 162 struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
 163 {
 164         struct nvdimm *nvdimm = nd_mapping->nvdimm;
 165
 166         WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
 167
 168         return dev_get_drvdata(&nvdimm->dev);
 169 }
 170 EXPORT_SYMBOL(to_ndd);
 171
 172 void nvdimm_drvdata_release(struct kref *kref)
 173 {
 174         struct nvdimm_drvdata *ndd = container_of(kref, typeof(*ndd), kref);
 175         struct device *dev = ndd->dev;
 176         struct resource *res, *_r;
 177
 178         dev_dbg(dev, "%s\n", __func__);
 179
 180         nvdimm_bus_lock(dev);
 181         for_each_dpa_resource_safe(ndd, res, _r)
 182                 nvdimm_free_dpa(ndd, res);
 183         nvdimm_bus_unlock(dev);
 184
 185         if (ndd->data && is_vmalloc_addr(ndd->data))
 186                 vfree(ndd->data);
 187         else
 188                 kfree(ndd->data);
 189         kfree(ndd);
 190         put_device(dev);
 191 }
 192
 193 void get_ndd(struct nvdimm_drvdata *ndd)
 194 {
 195         kref_get(&ndd->kref);
 196 }
 197
 198 void put_ndd(struct nvdimm_drvdata *ndd)
 199 {
 200         if (ndd)
 201                 kref_put(&ndd->kref, nvdimm_drvdata_release);
 202 }
 203
 204 const char *nvdimm_name(struct nvdimm *nvdimm)
 205 {
 206         return dev_name(&nvdimm->dev);
 207 }
 208 EXPORT_SYMBOL_GPL(nvdimm_name);
 209
 210 void *nvdimm_provider_data(struct nvdimm *nvdimm)
 211 {
 212         if (nvdimm)
 213                 return nvdimm->provider_data;
 214         return NULL;
 215 }
 216 EXPORT_SYMBOL_GPL(nvdimm_provider_data);
 217
 218 static ssize_t commands_show(struct device *dev,
 219                 struct device_attribute *attr, char *buf)
 220 {
 221         struct nvdimm *nvdimm = to_nvdimm(dev);
 222         int cmd, len = 0;
 223
 224         if (!nvdimm->dsm_mask)
 225                 return sprintf(buf, "\n");
 226
 227         for_each_set_bit(cmd, nvdimm->dsm_mask, BITS_PER_LONG)
 228                 len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
 229         len += sprintf(buf + len, "\n");
 230         return len;
 231 }
 232 static DEVICE_ATTR_RO(commands);
 233
 234 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 235                 char *buf)
 236 {
 237         struct nvdimm *nvdimm = to_nvdimm(dev);
 238
 239         /*
 240          * The state may be in the process of changing, userspace should
 241          * quiesce probing if it wants a static answer
 242          */
 243         nvdimm_bus_lock(dev);
 244         nvdimm_bus_unlock(dev);
 245         return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
 246                         ? "active" : "idle");
 247 }
 248 static DEVICE_ATTR_RO(state);
 249
 250 static struct attribute *nvdimm_attributes[] = {
 251         &dev_attr_state.attr,
 252         &dev_attr_commands.attr,
 253         NULL,
 254 };
 255
 256 struct attribute_group nvdimm_attribute_group = {
 257         .attrs = nvdimm_attributes,
 258 };
 259 EXPORT_SYMBOL_GPL(nvdimm_attribute_group);
 260
 261 struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
 262                 const struct attribute_group **groups, unsigned long flags,
 263                 unsigned long *dsm_mask)
 264 {
 265         struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
 266         struct device *dev;
 267
 268         if (!nvdimm)
 269                 return NULL;
 270
 271         nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
 272         if (nvdimm->id < 0) {
 273                 kfree(nvdimm);
 274                 return NULL;
 275         }
 276         nvdimm->provider_data = provider_data;
 277         nvdimm->flags = flags;
 278         nvdimm->dsm_mask = dsm_mask;
 279         atomic_set(&nvdimm->busy, 0);
 280         dev = &nvdimm->dev;
 281         dev_set_name(dev, "nmem%d", nvdimm->id);
 282         dev->parent = &nvdimm_bus->dev;
 283         dev->type = &nvdimm_device_type;
 284         dev->devt = MKDEV(nvdimm_major, nvdimm->id);
 285         dev->groups = groups;
 286         nd_device_register(dev);
 287
 288         return nvdimm;
 289 }
 290 EXPORT_SYMBOL_GPL(nvdimm_create);
 291
 292 /**
 293  * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
 294  * @nd_mapping: container of dpa-resource-root + labels
 295  * @nd_region: constrain available space check to this reference region
 296  * @overlap: calculate available space assuming this level of overlap
 297  *
 298  * Validate that a PMEM label, if present, aligns with the start of an
 299  * interleave set and truncate the available size at the lowest BLK
 300  * overlap point.
 301  *
 302  * The expectation is that this routine is called multiple times as it
 303  * probes for the largest BLK encroachment for any single member DIMM of
 304  * the interleave set.  Once that value is determined the PMEM-limit for
 305  * the set can be established.
 306  */
 307 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
 308                 struct nd_mapping *nd_mapping, resource_size_t *overlap)
 309 {
 310         resource_size_t map_start, map_end, busy = 0, available, blk_start;
 311         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 312         struct resource *res;
 313         const char *reason;
 314
 315         if (!ndd)
 316                 return 0;
 317
 318         map_start = nd_mapping->start;
 319         map_end = map_start + nd_mapping->size - 1;
 320         blk_start = max(map_start, map_end + 1 - *overlap);
 321         for_each_dpa_resource(ndd, res)
 322                 if (res->start >= map_start && res->start < map_end) {
 323                         if (strncmp(res->name, "blk", 3) == 0)
 324                                 blk_start = min(blk_start, res->start);
 325                         else if (res->start != map_start) {
 326                                 reason = "misaligned to iset";
 327                                 goto err;
 328                         } else {
 329                                 if (busy) {
 330                                         reason = "duplicate overlapping PMEM reservations?";
 331                                         goto err;
 332                                 }
 333                                 busy += resource_size(res);
 334                                 continue;
 335                         }
 336                 } else if (res->end >= map_start && res->end <= map_end) {
 337                         if (strncmp(res->name, "blk", 3) == 0) {
 338                                 /*
 339                                  * If a BLK allocation overlaps the start of
 340                                  * PMEM the entire interleave set may now only
 341                                  * be used for BLK.
 342                                  */
 343                                 blk_start = map_start;
 344                         } else {
 345                                 reason = "misaligned to iset";
 346                                 goto err;
 347                         }
 348                 } else if (map_start > res->start && map_start < res->end) {
 349                         /* total eclipse of the mapping */
 350                         busy += nd_mapping->size;
 351                         blk_start = map_start;
 352                 }
 353
 354         *overlap = map_end + 1 - blk_start;
 355         available = blk_start - map_start;
 356         if (busy < available)
 357                 return available - busy;
 358         return 0;
 359
 360  err:
 361         /*
 362          * Something is wrong, PMEM must align with the start of the
 363          * interleave set, and there can only be one allocation per set.
 364          */
 365         nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
 366         return 0;
 367 }
 368
 369 void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
 370 {
 371         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
 372         kfree(res->name);
 373         __release_region(&ndd->dpa, res->start, resource_size(res));
 374 }
 375
 376 struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
 377                 struct nd_label_id *label_id, resource_size_t start,
 378                 resource_size_t n)
 379 {
 380         char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
 381         struct resource *res;
 382
 383         if (!name)
 384                 return NULL;
 385
 386         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
 387         res = __request_region(&ndd->dpa, start, n, name, 0);
 388         if (!res)
 389                 kfree(name);
 390         return res;
 391 }
 392
 393 /**
 394  * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
 395  * @nvdimm: container of dpa-resource-root + labels
 396  * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
 397  */
 398 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
 399                 struct nd_label_id *label_id)
 400 {
 401         resource_size_t allocated = 0;
 402         struct resource *res;
 403
 404         for_each_dpa_resource(ndd, res)
 405                 if (strcmp(res->name, label_id->id) == 0)
 406                         allocated += resource_size(res);
 407
 408         return allocated;
 409 }
 410
 411 static int count_dimms(struct device *dev, void *c)
 412 {
 413         int *count = c;
 414
 415         if (is_nvdimm(dev))
 416                 (*count)++;
 417         return 0;
 418 }
 419
 420 int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
 421 {
 422         int count = 0;
 423         /* Flush any possible dimm registration failures */
 424         nd_synchronize();
 425
 426         device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
 427         dev_dbg(&nvdimm_bus->dev, "%s: count: %d\n", __func__, count);
 428         if (count != dimm_count)
 429                 return -ENXIO;
 430         return 0;
 431 }
 432 EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);