xref: /openbmc/linux/drivers/nvdimm/dimm.c (revision 0c7beb2d)
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/vmalloc.h>
14 #include <linux/module.h>
15 #include <linux/device.h>
16 #include <linux/sizes.h>
17 #include <linux/ndctl.h>
18 #include <linux/slab.h>
19 #include <linux/mm.h>
20 #include <linux/nd.h>
21 #include "label.h"
22 #include "nd.h"
23 
24 static int nvdimm_probe(struct device *dev)
25 {
26 	struct nvdimm_drvdata *ndd;
27 	int rc;
28 
29 	rc = nvdimm_security_setup_events(dev);
30 	if (rc < 0) {
31 		dev_err(dev, "security event setup failed: %d\n", rc);
32 		return rc;
33 	}
34 
35 	rc = nvdimm_check_config_data(dev);
36 	if (rc) {
37 		/* not required for non-aliased nvdimm, ex. NVDIMM-N */
38 		if (rc == -ENOTTY)
39 			rc = 0;
40 		return rc;
41 	}
42 
43 	/*
44 	 * The locked status bit reflects explicit status codes from the
45 	 * label reading commands, revalidate it each time the driver is
46 	 * activated and re-reads the label area.
47 	 */
48 	nvdimm_clear_locked(dev);
49 
50 	ndd = kzalloc(sizeof(*ndd), GFP_KERNEL);
51 	if (!ndd)
52 		return -ENOMEM;
53 
54 	dev_set_drvdata(dev, ndd);
55 	ndd->dpa.name = dev_name(dev);
56 	ndd->ns_current = -1;
57 	ndd->ns_next = -1;
58 	ndd->dpa.start = 0;
59 	ndd->dpa.end = -1;
60 	ndd->dev = dev;
61 	get_device(dev);
62 	kref_init(&ndd->kref);
63 
64 	/*
65 	 * Attempt to unlock, if the DIMM supports security commands,
66 	 * otherwise the locked indication is determined by explicit
67 	 * status codes from the label reading commands.
68 	 */
69 	rc = nvdimm_security_unlock(dev);
70 	if (rc < 0)
71 		dev_dbg(dev, "failed to unlock dimm: %d\n", rc);
72 
73 
74 	/*
75 	 * EACCES failures reading the namespace label-area-properties
76 	 * are interpreted as the DIMM capacity being locked but the
77 	 * namespace labels themselves being accessible.
78 	 */
79 	rc = nvdimm_init_nsarea(ndd);
80 	if (rc == -EACCES) {
81 		/*
82 		 * See nvdimm_namespace_common_probe() where we fail to
83 		 * allow namespaces to probe while the DIMM is locked,
84 		 * but we do allow for namespace enumeration.
85 		 */
86 		nvdimm_set_locked(dev);
87 		rc = 0;
88 	}
89 	if (rc)
90 		goto err;
91 
92 	/*
93 	 * EACCES failures reading the namespace label-data are
94 	 * interpreted as the label area being locked in addition to the
95 	 * DIMM capacity. We fail the dimm probe to prevent regions from
96 	 * attempting to parse the label area.
97 	 */
98 	rc = nd_label_data_init(ndd);
99 	if (rc == -EACCES)
100 		nvdimm_set_locked(dev);
101 	if (rc)
102 		goto err;
103 
104 	dev_dbg(dev, "config data size: %d\n", ndd->nsarea.config_size);
105 
106 	nvdimm_bus_lock(dev);
107 	if (ndd->ns_current >= 0) {
108 		rc = nd_label_reserve_dpa(ndd);
109 		if (rc == 0)
110 			nvdimm_set_aliasing(dev);
111 	}
112 	nvdimm_bus_unlock(dev);
113 
114 	if (rc)
115 		goto err;
116 
117 	return 0;
118 
119  err:
120 	put_ndd(ndd);
121 	return rc;
122 }
123 
124 static int nvdimm_remove(struct device *dev)
125 {
126 	struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
127 
128 	if (!ndd)
129 		return 0;
130 
131 	nvdimm_bus_lock(dev);
132 	dev_set_drvdata(dev, NULL);
133 	nvdimm_bus_unlock(dev);
134 	put_ndd(ndd);
135 
136 	return 0;
137 }
138 
139 static struct nd_device_driver nvdimm_driver = {
140 	.probe = nvdimm_probe,
141 	.remove = nvdimm_remove,
142 	.drv = {
143 		.name = "nvdimm",
144 	},
145 	.type = ND_DRIVER_DIMM,
146 };
147 
148 int __init nvdimm_init(void)
149 {
150 	return nd_driver_register(&nvdimm_driver);
151 }
152 
153 void nvdimm_exit(void)
154 {
155 	driver_unregister(&nvdimm_driver.drv);
156 }
157 
158 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DIMM);
159