xref: /openbmc/linux/drivers/nvdimm/dimm.c (revision 5d331b7f)
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_check_config_data(dev);
30 	if (rc) {
31 		/* not required for non-aliased nvdimm, ex. NVDIMM-N */
32 		if (rc == -ENOTTY)
33 			rc = 0;
34 		return rc;
35 	}
36 
37 	/* reset locked, to be validated below... */
38 	nvdimm_clear_locked(dev);
39 
40 	ndd = kzalloc(sizeof(*ndd), GFP_KERNEL);
41 	if (!ndd)
42 		return -ENOMEM;
43 
44 	dev_set_drvdata(dev, ndd);
45 	ndd->dpa.name = dev_name(dev);
46 	ndd->ns_current = -1;
47 	ndd->ns_next = -1;
48 	ndd->dpa.start = 0;
49 	ndd->dpa.end = -1;
50 	ndd->dev = dev;
51 	get_device(dev);
52 	kref_init(&ndd->kref);
53 
54 	/*
55 	 * EACCES failures reading the namespace label-area-properties
56 	 * are interpreted as the DIMM capacity being locked but the
57 	 * namespace labels themselves being accessible.
58 	 */
59 	rc = nvdimm_init_nsarea(ndd);
60 	if (rc == -EACCES) {
61 		/*
62 		 * See nvdimm_namespace_common_probe() where we fail to
63 		 * allow namespaces to probe while the DIMM is locked,
64 		 * but we do allow for namespace enumeration.
65 		 */
66 		nvdimm_set_locked(dev);
67 		rc = 0;
68 	}
69 	if (rc)
70 		goto err;
71 
72 	/*
73 	 * EACCES failures reading the namespace label-data are
74 	 * interpreted as the label area being locked in addition to the
75 	 * DIMM capacity. We fail the dimm probe to prevent regions from
76 	 * attempting to parse the label area.
77 	 */
78 	rc = nd_label_data_init(ndd);
79 	if (rc == -EACCES)
80 		nvdimm_set_locked(dev);
81 	if (rc)
82 		goto err;
83 
84 	dev_dbg(dev, "config data size: %d\n", ndd->nsarea.config_size);
85 
86 	nvdimm_bus_lock(dev);
87 	if (ndd->ns_current >= 0) {
88 		rc = nd_label_reserve_dpa(ndd);
89 		if (rc == 0)
90 			nvdimm_set_aliasing(dev);
91 	}
92 	nvdimm_bus_unlock(dev);
93 
94 	if (rc)
95 		goto err;
96 
97 	return 0;
98 
99  err:
100 	put_ndd(ndd);
101 	return rc;
102 }
103 
104 static int nvdimm_remove(struct device *dev)
105 {
106 	struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
107 
108 	if (!ndd)
109 		return 0;
110 
111 	nvdimm_bus_lock(dev);
112 	dev_set_drvdata(dev, NULL);
113 	nvdimm_bus_unlock(dev);
114 	put_ndd(ndd);
115 
116 	return 0;
117 }
118 
119 static struct nd_device_driver nvdimm_driver = {
120 	.probe = nvdimm_probe,
121 	.remove = nvdimm_remove,
122 	.drv = {
123 		.name = "nvdimm",
124 	},
125 	.type = ND_DRIVER_DIMM,
126 };
127 
128 int __init nvdimm_init(void)
129 {
130 	return nd_driver_register(&nvdimm_driver);
131 }
132 
133 void nvdimm_exit(void)
134 {
135 	driver_unregister(&nvdimm_driver.drv);
136 }
137 
138 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DIMM);
139