xref: /openbmc/linux/drivers/nvdimm/region.c (revision 842ed298)
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 int 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 	return 0;
113 }
114 
115 static int child_notify(struct device *dev, void *data)
116 {
117 	nd_device_notify(dev, *(enum nvdimm_event *) data);
118 	return 0;
119 }
120 
121 static void nd_region_notify(struct device *dev, enum nvdimm_event event)
122 {
123 	if (event == NVDIMM_REVALIDATE_POISON) {
124 		struct nd_region *nd_region = to_nd_region(dev);
125 
126 		if (is_memory(&nd_region->dev)) {
127 			struct range range = {
128 				.start = nd_region->ndr_start,
129 				.end = nd_region->ndr_start +
130 					nd_region->ndr_size - 1,
131 			};
132 
133 			nvdimm_badblocks_populate(nd_region,
134 					&nd_region->bb, &range);
135 			if (nd_region->bb_state)
136 				sysfs_notify_dirent(nd_region->bb_state);
137 		}
138 	}
139 	device_for_each_child(dev, &event, child_notify);
140 }
141 
142 static struct nd_device_driver nd_region_driver = {
143 	.probe = nd_region_probe,
144 	.remove = nd_region_remove,
145 	.notify = nd_region_notify,
146 	.drv = {
147 		.name = "nd_region",
148 	},
149 	.type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM,
150 };
151 
152 int __init nd_region_init(void)
153 {
154 	return nd_driver_register(&nd_region_driver);
155 }
156 
157 void nd_region_exit(void)
158 {
159 	driver_unregister(&nd_region_driver.drv);
160 }
161 
162 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM);
163 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK);
164