xref: /openbmc/linux/drivers/nvdimm/dimm.c (revision 55fd7e02)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4  */
5 #include <linux/vmalloc.h>
6 #include <linux/module.h>
7 #include <linux/device.h>
8 #include <linux/sizes.h>
9 #include <linux/ndctl.h>
10 #include <linux/slab.h>
11 #include <linux/mm.h>
12 #include <linux/nd.h>
13 #include "label.h"
14 #include "nd.h"
15 
16 static int nvdimm_probe(struct device *dev)
17 {
18 	struct nvdimm_drvdata *ndd;
19 	int rc;
20 
21 	rc = nvdimm_security_setup_events(dev);
22 	if (rc < 0) {
23 		dev_err(dev, "security event setup failed: %d\n", rc);
24 		return rc;
25 	}
26 
27 	rc = nvdimm_check_config_data(dev);
28 	if (rc) {
29 		/* not required for non-aliased nvdimm, ex. NVDIMM-N */
30 		if (rc == -ENOTTY)
31 			rc = 0;
32 		return rc;
33 	}
34 
35 	/*
36 	 * The locked status bit reflects explicit status codes from the
37 	 * label reading commands, revalidate it each time the driver is
38 	 * activated and re-reads the label area.
39 	 */
40 	nvdimm_clear_locked(dev);
41 
42 	ndd = kzalloc(sizeof(*ndd), GFP_KERNEL);
43 	if (!ndd)
44 		return -ENOMEM;
45 
46 	dev_set_drvdata(dev, ndd);
47 	ndd->dpa.name = dev_name(dev);
48 	ndd->ns_current = -1;
49 	ndd->ns_next = -1;
50 	ndd->dpa.start = 0;
51 	ndd->dpa.end = -1;
52 	ndd->dev = dev;
53 	get_device(dev);
54 	kref_init(&ndd->kref);
55 
56 	/*
57 	 * Attempt to unlock, if the DIMM supports security commands,
58 	 * otherwise the locked indication is determined by explicit
59 	 * status codes from the label reading commands.
60 	 */
61 	rc = nvdimm_security_unlock(dev);
62 	if (rc < 0)
63 		dev_dbg(dev, "failed to unlock dimm: %d\n", rc);
64 
65 
66 	/*
67 	 * EACCES failures reading the namespace label-area-properties
68 	 * are interpreted as the DIMM capacity being locked but the
69 	 * namespace labels themselves being accessible.
70 	 */
71 	rc = nvdimm_init_nsarea(ndd);
72 	if (rc == -EACCES) {
73 		/*
74 		 * See nvdimm_namespace_common_probe() where we fail to
75 		 * allow namespaces to probe while the DIMM is locked,
76 		 * but we do allow for namespace enumeration.
77 		 */
78 		nvdimm_set_locked(dev);
79 		rc = 0;
80 	}
81 	if (rc)
82 		goto err;
83 
84 	/*
85 	 * EACCES failures reading the namespace label-data are
86 	 * interpreted as the label area being locked in addition to the
87 	 * DIMM capacity. We fail the dimm probe to prevent regions from
88 	 * attempting to parse the label area.
89 	 */
90 	rc = nd_label_data_init(ndd);
91 	if (rc == -EACCES)
92 		nvdimm_set_locked(dev);
93 	if (rc)
94 		goto err;
95 
96 	dev_dbg(dev, "config data size: %d\n", ndd->nsarea.config_size);
97 
98 	nvdimm_bus_lock(dev);
99 	if (ndd->ns_current >= 0) {
100 		rc = nd_label_reserve_dpa(ndd);
101 		if (rc == 0)
102 			nvdimm_set_labeling(dev);
103 	}
104 	nvdimm_bus_unlock(dev);
105 
106 	if (rc)
107 		goto err;
108 
109 	return 0;
110 
111  err:
112 	put_ndd(ndd);
113 	return rc;
114 }
115 
116 static int nvdimm_remove(struct device *dev)
117 {
118 	struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
119 
120 	if (!ndd)
121 		return 0;
122 
123 	nvdimm_bus_lock(dev);
124 	dev_set_drvdata(dev, NULL);
125 	nvdimm_bus_unlock(dev);
126 	put_ndd(ndd);
127 
128 	return 0;
129 }
130 
131 static struct nd_device_driver nvdimm_driver = {
132 	.probe = nvdimm_probe,
133 	.remove = nvdimm_remove,
134 	.drv = {
135 		.name = "nvdimm",
136 	},
137 	.type = ND_DRIVER_DIMM,
138 };
139 
140 int __init nvdimm_init(void)
141 {
142 	return nd_driver_register(&nvdimm_driver);
143 }
144 
145 void nvdimm_exit(void)
146 {
147 	driver_unregister(&nvdimm_driver.drv);
148 }
149 
150 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DIMM);
151