Merge tag 'media/v6.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
[linux-2.6-microblaze.git] / 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/memregion.h>
6 #include <linux/cpumask.h>
7 #include <linux/module.h>
8 #include <linux/device.h>
9 #include <linux/nd.h>
10 #include "nd-core.h"
11 #include "nd.h"
12
13 static int nd_region_probe(struct device *dev)
14 {
15         int err, rc;
16         static unsigned long once;
17         struct nd_region_data *ndrd;
18         struct nd_region *nd_region = to_nd_region(dev);
19         struct range range = {
20                 .start = nd_region->ndr_start,
21                 .end = nd_region->ndr_start + nd_region->ndr_size - 1,
22         };
23
24         if (nd_region->num_lanes > num_online_cpus()
25                         && nd_region->num_lanes < num_possible_cpus()
26                         && !test_and_set_bit(0, &once)) {
27                 dev_dbg(dev, "online cpus (%d) < concurrent i/o lanes (%d) < possible cpus (%d)\n",
28                                 num_online_cpus(), nd_region->num_lanes,
29                                 num_possible_cpus());
30                 dev_dbg(dev, "setting nr_cpus=%d may yield better libnvdimm device performance\n",
31                                 nd_region->num_lanes);
32         }
33
34         rc = nd_region_activate(nd_region);
35         if (rc)
36                 return rc;
37
38         if (devm_init_badblocks(dev, &nd_region->bb))
39                 return -ENODEV;
40         nd_region->bb_state =
41                 sysfs_get_dirent(nd_region->dev.kobj.sd, "badblocks");
42         if (!nd_region->bb_state)
43                 dev_warn(dev, "'badblocks' notification disabled\n");
44         nvdimm_badblocks_populate(nd_region, &nd_region->bb, &range);
45
46         rc = nd_region_register_namespaces(nd_region, &err);
47         if (rc < 0)
48                 return rc;
49
50         ndrd = dev_get_drvdata(dev);
51         ndrd->ns_active = rc;
52         ndrd->ns_count = rc + err;
53
54         if (rc && err && rc == err)
55                 return -ENODEV;
56
57         nd_region->btt_seed = nd_btt_create(nd_region);
58         nd_region->pfn_seed = nd_pfn_create(nd_region);
59         nd_region->dax_seed = nd_dax_create(nd_region);
60         if (err == 0)
61                 return 0;
62
63         /*
64          * Given multiple namespaces per region, we do not want to
65          * disable all the successfully registered peer namespaces upon
66          * a single registration failure.  If userspace is missing a
67          * namespace that it expects it can disable/re-enable the region
68          * to retry discovery after correcting the failure.
69          * <regionX>/namespaces returns the current
70          * "<async-registered>/<total>" namespace count.
71          */
72         dev_err(dev, "failed to register %d namespace%s, continuing...\n",
73                         err, err == 1 ? "" : "s");
74         return 0;
75 }
76
77 static int child_unregister(struct device *dev, void *data)
78 {
79         nd_device_unregister(dev, ND_SYNC);
80         return 0;
81 }
82
83 static void nd_region_remove(struct device *dev)
84 {
85         struct nd_region *nd_region = to_nd_region(dev);
86
87         device_for_each_child(dev, NULL, child_unregister);
88
89         /* flush attribute readers and disable */
90         nvdimm_bus_lock(dev);
91         nd_region->ns_seed = NULL;
92         nd_region->btt_seed = NULL;
93         nd_region->pfn_seed = NULL;
94         nd_region->dax_seed = NULL;
95         dev_set_drvdata(dev, NULL);
96         nvdimm_bus_unlock(dev);
97
98         /*
99          * Note, this assumes device_lock() context to not race
100          * nd_region_notify()
101          */
102         sysfs_put(nd_region->bb_state);
103         nd_region->bb_state = NULL;
104
105         /*
106          * Try to flush caches here since a disabled region may be subject to
107          * secure erase while disabled, and previous dirty data should not be
108          * written back to a new instance of the region. This only matters on
109          * bare metal where security commands are available, so silent failure
110          * here is ok.
111          */
112         if (cpu_cache_has_invalidate_memregion())
113                 cpu_cache_invalidate_memregion(IORES_DESC_PERSISTENT_MEMORY);
114 }
115
116 static int child_notify(struct device *dev, void *data)
117 {
118         nd_device_notify(dev, *(enum nvdimm_event *) data);
119         return 0;
120 }
121
122 static void nd_region_notify(struct device *dev, enum nvdimm_event event)
123 {
124         if (event == NVDIMM_REVALIDATE_POISON) {
125                 struct nd_region *nd_region = to_nd_region(dev);
126
127                 if (is_memory(&nd_region->dev)) {
128                         struct range range = {
129                                 .start = nd_region->ndr_start,
130                                 .end = nd_region->ndr_start +
131                                         nd_region->ndr_size - 1,
132                         };
133
134                         nvdimm_badblocks_populate(nd_region,
135                                         &nd_region->bb, &range);
136                         if (nd_region->bb_state)
137                                 sysfs_notify_dirent(nd_region->bb_state);
138                 }
139         }
140         device_for_each_child(dev, &event, child_notify);
141 }
142
143 static struct nd_device_driver nd_region_driver = {
144         .probe = nd_region_probe,
145         .remove = nd_region_remove,
146         .notify = nd_region_notify,
147         .drv = {
148                 .name = "nd_region",
149         },
150         .type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM,
151 };
152
153 int __init nd_region_init(void)
154 {
155         return nd_driver_register(&nd_region_driver);
156 }
157
158 void nd_region_exit(void)
159 {
160         driver_unregister(&nd_region_driver.drv);
161 }
162
163 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM);