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