xref: /openbmc/linux/drivers/nvdimm/region.c (revision 7f6964c5)
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 	rc = nd_region_register_namespaces(nd_region, &err);
38 	if (rc < 0)
39 		return rc;
40 
41 	ndrd = dev_get_drvdata(dev);
42 	ndrd->ns_active = rc;
43 	ndrd->ns_count = rc + err;
44 
45 	if (rc && err && rc == err)
46 		return -ENODEV;
47 
48 	if (is_nd_pmem(&nd_region->dev)) {
49 		struct resource ndr_res;
50 
51 		if (devm_init_badblocks(dev, &nd_region->bb))
52 			return -ENODEV;
53 		nd_region->bb_state = sysfs_get_dirent(nd_region->dev.kobj.sd,
54 						       "badblocks");
55 		if (!nd_region->bb_state)
56 			dev_warn(&nd_region->dev,
57 					"'badblocks' notification disabled\n");
58 		ndr_res.start = nd_region->ndr_start;
59 		ndr_res.end = nd_region->ndr_start + nd_region->ndr_size - 1;
60 		nvdimm_badblocks_populate(nd_region, &nd_region->bb, &ndr_res);
61 	}
62 
63 	nd_region->btt_seed = nd_btt_create(nd_region);
64 	nd_region->pfn_seed = nd_pfn_create(nd_region);
65 	nd_region->dax_seed = nd_dax_create(nd_region);
66 	if (err == 0)
67 		return 0;
68 
69 	/*
70 	 * Given multiple namespaces per region, we do not want to
71 	 * disable all the successfully registered peer namespaces upon
72 	 * a single registration failure.  If userspace is missing a
73 	 * namespace that it expects it can disable/re-enable the region
74 	 * to retry discovery after correcting the failure.
75 	 * <regionX>/namespaces returns the current
76 	 * "<async-registered>/<total>" namespace count.
77 	 */
78 	dev_err(dev, "failed to register %d namespace%s, continuing...\n",
79 			err, err == 1 ? "" : "s");
80 	return 0;
81 }
82 
83 static int child_unregister(struct device *dev, void *data)
84 {
85 	nd_device_unregister(dev, ND_SYNC);
86 	return 0;
87 }
88 
89 static int nd_region_remove(struct device *dev)
90 {
91 	struct nd_region *nd_region = to_nd_region(dev);
92 
93 	device_for_each_child(dev, NULL, child_unregister);
94 
95 	/* flush attribute readers and disable */
96 	nvdimm_bus_lock(dev);
97 	nd_region->ns_seed = NULL;
98 	nd_region->btt_seed = NULL;
99 	nd_region->pfn_seed = NULL;
100 	nd_region->dax_seed = NULL;
101 	dev_set_drvdata(dev, NULL);
102 	nvdimm_bus_unlock(dev);
103 
104 	/*
105 	 * Note, this assumes device_lock() context to not race
106 	 * nd_region_notify()
107 	 */
108 	sysfs_put(nd_region->bb_state);
109 	nd_region->bb_state = NULL;
110 
111 	return 0;
112 }
113 
114 static int child_notify(struct device *dev, void *data)
115 {
116 	nd_device_notify(dev, *(enum nvdimm_event *) data);
117 	return 0;
118 }
119 
120 static void nd_region_notify(struct device *dev, enum nvdimm_event event)
121 {
122 	if (event == NVDIMM_REVALIDATE_POISON) {
123 		struct nd_region *nd_region = to_nd_region(dev);
124 		struct resource res;
125 
126 		if (is_nd_pmem(&nd_region->dev)) {
127 			res.start = nd_region->ndr_start;
128 			res.end = nd_region->ndr_start +
129 				nd_region->ndr_size - 1;
130 			nvdimm_badblocks_populate(nd_region,
131 					&nd_region->bb, &res);
132 			if (nd_region->bb_state)
133 				sysfs_notify_dirent(nd_region->bb_state);
134 		}
135 	}
136 	device_for_each_child(dev, &event, child_notify);
137 }
138 
139 static struct nd_device_driver nd_region_driver = {
140 	.probe = nd_region_probe,
141 	.remove = nd_region_remove,
142 	.notify = nd_region_notify,
143 	.drv = {
144 		.name = "nd_region",
145 	},
146 	.type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM,
147 };
148 
149 int __init nd_region_init(void)
150 {
151 	return nd_driver_register(&nd_region_driver);
152 }
153 
154 void nd_region_exit(void)
155 {
156 	driver_unregister(&nd_region_driver.drv);
157 }
158 
159 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM);
160 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK);
161