xref: /openbmc/linux/drivers/nvdimm/dax_devs.c (revision 6d99a79c)
1 /*
2  * Copyright(c) 2013-2016 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/device.h>
14 #include <linux/sizes.h>
15 #include <linux/slab.h>
16 #include <linux/mm.h>
17 #include "nd-core.h"
18 #include "pfn.h"
19 #include "nd.h"
20 
21 static void nd_dax_release(struct device *dev)
22 {
23 	struct nd_region *nd_region = to_nd_region(dev->parent);
24 	struct nd_dax *nd_dax = to_nd_dax(dev);
25 	struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
26 
27 	dev_dbg(dev, "trace\n");
28 	nd_detach_ndns(dev, &nd_pfn->ndns);
29 	ida_simple_remove(&nd_region->dax_ida, nd_pfn->id);
30 	kfree(nd_pfn->uuid);
31 	kfree(nd_dax);
32 }
33 
34 static struct device_type nd_dax_device_type = {
35 	.name = "nd_dax",
36 	.release = nd_dax_release,
37 };
38 
39 bool is_nd_dax(struct device *dev)
40 {
41 	return dev ? dev->type == &nd_dax_device_type : false;
42 }
43 EXPORT_SYMBOL(is_nd_dax);
44 
45 struct nd_dax *to_nd_dax(struct device *dev)
46 {
47 	struct nd_dax *nd_dax = container_of(dev, struct nd_dax, nd_pfn.dev);
48 
49 	WARN_ON(!is_nd_dax(dev));
50 	return nd_dax;
51 }
52 EXPORT_SYMBOL(to_nd_dax);
53 
54 static const struct attribute_group *nd_dax_attribute_groups[] = {
55 	&nd_pfn_attribute_group,
56 	&nd_device_attribute_group,
57 	&nd_numa_attribute_group,
58 	NULL,
59 };
60 
61 static struct nd_dax *nd_dax_alloc(struct nd_region *nd_region)
62 {
63 	struct nd_pfn *nd_pfn;
64 	struct nd_dax *nd_dax;
65 	struct device *dev;
66 
67 	nd_dax = kzalloc(sizeof(*nd_dax), GFP_KERNEL);
68 	if (!nd_dax)
69 		return NULL;
70 
71 	nd_pfn = &nd_dax->nd_pfn;
72 	nd_pfn->id = ida_simple_get(&nd_region->dax_ida, 0, 0, GFP_KERNEL);
73 	if (nd_pfn->id < 0) {
74 		kfree(nd_dax);
75 		return NULL;
76 	}
77 
78 	dev = &nd_pfn->dev;
79 	dev_set_name(dev, "dax%d.%d", nd_region->id, nd_pfn->id);
80 	dev->groups = nd_dax_attribute_groups;
81 	dev->type = &nd_dax_device_type;
82 	dev->parent = &nd_region->dev;
83 
84 	return nd_dax;
85 }
86 
87 struct device *nd_dax_create(struct nd_region *nd_region)
88 {
89 	struct device *dev = NULL;
90 	struct nd_dax *nd_dax;
91 
92 	if (!is_memory(&nd_region->dev))
93 		return NULL;
94 
95 	nd_dax = nd_dax_alloc(nd_region);
96 	if (nd_dax)
97 		dev = nd_pfn_devinit(&nd_dax->nd_pfn, NULL);
98 	__nd_device_register(dev);
99 	return dev;
100 }
101 
102 int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns)
103 {
104 	int rc;
105 	struct nd_dax *nd_dax;
106 	struct device *dax_dev;
107 	struct nd_pfn *nd_pfn;
108 	struct nd_pfn_sb *pfn_sb;
109 	struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
110 
111 	if (ndns->force_raw)
112 		return -ENODEV;
113 
114 	switch (ndns->claim_class) {
115 	case NVDIMM_CCLASS_NONE:
116 	case NVDIMM_CCLASS_DAX:
117 		break;
118 	default:
119 		return -ENODEV;
120 	}
121 
122 	nvdimm_bus_lock(&ndns->dev);
123 	nd_dax = nd_dax_alloc(nd_region);
124 	nd_pfn = &nd_dax->nd_pfn;
125 	dax_dev = nd_pfn_devinit(nd_pfn, ndns);
126 	nvdimm_bus_unlock(&ndns->dev);
127 	if (!dax_dev)
128 		return -ENOMEM;
129 	pfn_sb = devm_kzalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
130 	nd_pfn->pfn_sb = pfn_sb;
131 	rc = nd_pfn_validate(nd_pfn, DAX_SIG);
132 	dev_dbg(dev, "dax: %s\n", rc == 0 ? dev_name(dax_dev) : "<none>");
133 	if (rc < 0) {
134 		nd_detach_ndns(dax_dev, &nd_pfn->ndns);
135 		put_device(dax_dev);
136 	} else
137 		__nd_device_register(dax_dev);
138 
139 	return rc;
140 }
141 EXPORT_SYMBOL(nd_dax_probe);
142