drivers/nvdimm/region.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 #include <linux/cpumask.h>
  14 #include <linux/module.h>
  15 #include <linux/device.h>
  16 #include <linux/nd.h>
  17 #include "nd-core.h"
  18 #include "nd.h"
  19
  20 static int nd_region_probe(struct device *dev)
  21 {
  22         int err, rc;
  23         static unsigned long once;
  24         struct nd_region_data *ndrd;
  25         struct nd_region *nd_region = to_nd_region(dev);
  26
  27         if (nd_region->num_lanes > num_online_cpus()
  28                         && nd_region->num_lanes < num_possible_cpus()
  29                         && !test_and_set_bit(0, &once)) {
  30                 dev_info(dev, "online cpus (%d) < concurrent i/o lanes (%d) < possible cpus (%d)\n",
  31                                 num_online_cpus(), nd_region->num_lanes,
  32                                 num_possible_cpus());
  33                 dev_info(dev, "setting nr_cpus=%d may yield better libnvdimm device performance\n",
  34                                 nd_region->num_lanes);
  35         }
  36
  37         rc = nd_region_activate(nd_region);
  38         if (rc)
  39                 return rc;
  40
  41         rc = nd_blk_region_init(nd_region);
  42         if (rc)
  43                 return rc;
  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         if (is_nd_pmem(&nd_region->dev)) {
  57                 struct resource ndr_res;
  58
  59                 if (devm_init_badblocks(dev, &nd_region->bb))
  60                         return -ENODEV;
  61                 ndr_res.start = nd_region->ndr_start;
  62                 ndr_res.end = nd_region->ndr_start + nd_region->ndr_size - 1;
  63                 nvdimm_badblocks_populate(nd_region,
  64                                 &nd_region->bb, &ndr_res);
  65         }
  66
  67         nd_region->btt_seed = nd_btt_create(nd_region);
  68         nd_region->pfn_seed = nd_pfn_create(nd_region);
  69         nd_region->dax_seed = nd_dax_create(nd_region);
  70         if (err == 0)
  71                 return 0;
  72
  73         /*
  74          * Given multiple namespaces per region, we do not want to
  75          * disable all the successfully registered peer namespaces upon
  76          * a single registration failure.  If userspace is missing a
  77          * namespace that it expects it can disable/re-enable the region
  78          * to retry discovery after correcting the failure.
  79          * <regionX>/namespaces returns the current
  80          * "<async-registered>/<total>" namespace count.
  81          */
  82         dev_err(dev, "failed to register %d namespace%s, continuing...\n",
  83                         err, err == 1 ? "" : "s");
  84         return 0;
  85 }
  86
  87 static int child_unregister(struct device *dev, void *data)
  88 {
  89         nd_device_unregister(dev, ND_SYNC);
  90         return 0;
  91 }
  92
  93 static int nd_region_remove(struct device *dev)
  94 {
  95         struct nd_region *nd_region = to_nd_region(dev);
  96
  97         device_for_each_child(dev, NULL, child_unregister);
  98
  99         /* flush attribute readers and disable */
 100         nvdimm_bus_lock(dev);
 101         nd_region->ns_seed = NULL;
 102         nd_region->btt_seed = NULL;
 103         nd_region->pfn_seed = NULL;
 104         nd_region->dax_seed = NULL;
 105         dev_set_drvdata(dev, NULL);
 106         nvdimm_bus_unlock(dev);
 107
 108         return 0;
 109 }
 110
 111 static int child_notify(struct device *dev, void *data)
 112 {
 113         nd_device_notify(dev, *(enum nvdimm_event *) data);
 114         return 0;
 115 }
 116
 117 static void nd_region_notify(struct device *dev, enum nvdimm_event event)
 118 {
 119         if (event == NVDIMM_REVALIDATE_POISON) {
 120                 struct nd_region *nd_region = to_nd_region(dev);
 121                 struct resource res;
 122
 123                 if (is_nd_pmem(&nd_region->dev)) {
 124                         res.start = nd_region->ndr_start;
 125                         res.end = nd_region->ndr_start +
 126                                 nd_region->ndr_size - 1;
 127                         nvdimm_badblocks_populate(nd_region,
 128                                         &nd_region->bb, &res);
 129                 }
 130         }
 131         device_for_each_child(dev, &event, child_notify);
 132 }
 133
 134 static struct nd_device_driver nd_region_driver = {
 135         .probe = nd_region_probe,
 136         .remove = nd_region_remove,
 137         .notify = nd_region_notify,
 138         .drv = {
 139                 .name = "nd_region",
 140         },
 141         .type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM,
 142 };
 143
 144 int __init nd_region_init(void)
 145 {
 146         return nd_driver_register(&nd_region_driver);
 147 }
 148
 149 void nd_region_exit(void)
 150 {
 151         driver_unregister(&nd_region_driver.drv);
 152 }
 153
 154 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM);
 155 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK);