drivers/nvdimm/region.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
   4  */
   5 #include <linux/cpumask.h>
   6 #include <linux/module.h>
   7 #include <linux/device.h>
   8 #include <linux/nd.h>
   9 #include "nd-core.h"
  10 #include "nd.h"
  11
  12 static int nd_region_probe(struct device *dev)
  13 {
  14         int err, rc;
  15         static unsigned long once;
  16         struct nd_region_data *ndrd;
  17         struct nd_region *nd_region = to_nd_region(dev);
  18
  19         if (nd_region->num_lanes > num_online_cpus()
  20                         && nd_region->num_lanes < num_possible_cpus()
  21                         && !test_and_set_bit(0, &once)) {
  22                 dev_dbg(dev, "online cpus (%d) < concurrent i/o lanes (%d) < possible cpus (%d)\n",
  23                                 num_online_cpus(), nd_region->num_lanes,
  24                                 num_possible_cpus());
  25                 dev_dbg(dev, "setting nr_cpus=%d may yield better libnvdimm device performance\n",
  26                                 nd_region->num_lanes);
  27         }
  28
  29         rc = nd_region_activate(nd_region);
  30         if (rc)
  31                 return rc;
  32
  33         rc = nd_blk_region_init(nd_region);
  34         if (rc)
  35                 return rc;
  36
  37         if (is_memory(&nd_region->dev)) {
  38                 struct range range = {
  39                         .start = nd_region->ndr_start,
  40                         .end = nd_region->ndr_start + nd_region->ndr_size - 1,
  41                 };
  42
  43                 if (devm_init_badblocks(dev, &nd_region->bb))
  44                         return -ENODEV;
  45                 nd_region->bb_state = sysfs_get_dirent(nd_region->dev.kobj.sd,
  46                                                        "badblocks");
  47                 if (!nd_region->bb_state)
  48                         dev_warn(&nd_region->dev,
  49                                         "'badblocks' notification disabled\n");
  50                 nvdimm_badblocks_populate(nd_region, &nd_region->bb, &range);
  51         }
  52
  53         rc = nd_region_register_namespaces(nd_region, &err);
  54         if (rc < 0)
  55                 return rc;
  56
  57         ndrd = dev_get_drvdata(dev);
  58         ndrd->ns_active = rc;
  59         ndrd->ns_count = rc + err;
  60
  61         if (rc && err && rc == err)
  62                 return -ENODEV;
  63
  64         nd_region->btt_seed = nd_btt_create(nd_region);
  65         nd_region->pfn_seed = nd_pfn_create(nd_region);
  66         nd_region->dax_seed = nd_dax_create(nd_region);
  67         if (err == 0)
  68                 return 0;
  69
  70         /*
  71          * Given multiple namespaces per region, we do not want to
  72          * disable all the successfully registered peer namespaces upon
  73          * a single registration failure.  If userspace is missing a
  74          * namespace that it expects it can disable/re-enable the region
  75          * to retry discovery after correcting the failure.
  76          * <regionX>/namespaces returns the current
  77          * "<async-registered>/<total>" namespace count.
  78          */
  79         dev_err(dev, "failed to register %d namespace%s, continuing...\n",
  80                         err, err == 1 ? "" : "s");
  81         return 0;
  82 }
  83
  84 static int child_unregister(struct device *dev, void *data)
  85 {
  86         nd_device_unregister(dev, ND_SYNC);
  87         return 0;
  88 }
  89
  90 static void nd_region_remove(struct device *dev)
  91 {
  92         struct nd_region *nd_region = to_nd_region(dev);
  93
  94         device_for_each_child(dev, NULL, child_unregister);
  95
  96         /* flush attribute readers and disable */
  97         nvdimm_bus_lock(dev);
  98         nd_region->ns_seed = NULL;
  99         nd_region->btt_seed = NULL;
 100         nd_region->pfn_seed = NULL;
 101         nd_region->dax_seed = NULL;
 102         dev_set_drvdata(dev, NULL);
 103         nvdimm_bus_unlock(dev);
 104
 105         /*
 106          * Note, this assumes nd_device_lock() context to not race
 107          * nd_region_notify()
 108          */
 109         sysfs_put(nd_region->bb_state);
 110         nd_region->bb_state = NULL;
 111 }
 112
 113 static int child_notify(struct device *dev, void *data)
 114 {
 115         nd_device_notify(dev, *(enum nvdimm_event *) data);
 116         return 0;
 117 }
 118
 119 static void nd_region_notify(struct device *dev, enum nvdimm_event event)
 120 {
 121         if (event == NVDIMM_REVALIDATE_POISON) {
 122                 struct nd_region *nd_region = to_nd_region(dev);
 123
 124                 if (is_memory(&nd_region->dev)) {
 125                         struct range range = {
 126                                 .start = nd_region->ndr_start,
 127                                 .end = nd_region->ndr_start +
 128                                         nd_region->ndr_size - 1,
 129                         };
 130
 131                         nvdimm_badblocks_populate(nd_region,
 132                                         &nd_region->bb, &range);
 133                         if (nd_region->bb_state)
 134                                 sysfs_notify_dirent(nd_region->bb_state);
 135                 }
 136         }
 137         device_for_each_child(dev, &event, child_notify);
 138 }
 139
 140 static struct nd_device_driver nd_region_driver = {
 141         .probe = nd_region_probe,
 142         .remove = nd_region_remove,
 143         .notify = nd_region_notify,
 144         .drv = {
 145                 .name = "nd_region",
 146         },
 147         .type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM,
 148 };
 149
 150 int __init nd_region_init(void)
 151 {
 152         return nd_driver_register(&nd_region_driver);
 153 }
 154
 155 void nd_region_exit(void)
 156 {
 157         driver_unregister(&nd_region_driver.drv);
 158 }
 159
 160 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM);
 161 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK);