xref: /openbmc/linux/drivers/nvdimm/dax_devs.c (revision 2ef5a7f1)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
4  */
5 #include <linux/device.h>
6 #include <linux/sizes.h>
7 #include <linux/slab.h>
8 #include <linux/mm.h>
9 #include "nd-core.h"
10 #include "pfn.h"
11 #include "nd.h"
12 
13 static void nd_dax_release(struct device *dev)
14 {
15 	struct nd_region *nd_region = to_nd_region(dev->parent);
16 	struct nd_dax *nd_dax = to_nd_dax(dev);
17 	struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
18 
19 	dev_dbg(dev, "trace\n");
20 	nd_detach_ndns(dev, &nd_pfn->ndns);
21 	ida_simple_remove(&nd_region->dax_ida, nd_pfn->id);
22 	kfree(nd_pfn->uuid);
23 	kfree(nd_dax);
24 }
25 
26 static struct device_type nd_dax_device_type = {
27 	.name = "nd_dax",
28 	.release = nd_dax_release,
29 };
30 
31 bool is_nd_dax(struct device *dev)
32 {
33 	return dev ? dev->type == &nd_dax_device_type : false;
34 }
35 EXPORT_SYMBOL(is_nd_dax);
36 
37 struct nd_dax *to_nd_dax(struct device *dev)
38 {
39 	struct nd_dax *nd_dax = container_of(dev, struct nd_dax, nd_pfn.dev);
40 
41 	WARN_ON(!is_nd_dax(dev));
42 	return nd_dax;
43 }
44 EXPORT_SYMBOL(to_nd_dax);
45 
46 static const struct attribute_group *nd_dax_attribute_groups[] = {
47 	&nd_pfn_attribute_group,
48 	&nd_device_attribute_group,
49 	&nd_numa_attribute_group,
50 	NULL,
51 };
52 
53 static struct nd_dax *nd_dax_alloc(struct nd_region *nd_region)
54 {
55 	struct nd_pfn *nd_pfn;
56 	struct nd_dax *nd_dax;
57 	struct device *dev;
58 
59 	nd_dax = kzalloc(sizeof(*nd_dax), GFP_KERNEL);
60 	if (!nd_dax)
61 		return NULL;
62 
63 	nd_pfn = &nd_dax->nd_pfn;
64 	nd_pfn->id = ida_simple_get(&nd_region->dax_ida, 0, 0, GFP_KERNEL);
65 	if (nd_pfn->id < 0) {
66 		kfree(nd_dax);
67 		return NULL;
68 	}
69 
70 	dev = &nd_pfn->dev;
71 	dev_set_name(dev, "dax%d.%d", nd_region->id, nd_pfn->id);
72 	dev->groups = nd_dax_attribute_groups;
73 	dev->type = &nd_dax_device_type;
74 	dev->parent = &nd_region->dev;
75 
76 	return nd_dax;
77 }
78 
79 struct device *nd_dax_create(struct nd_region *nd_region)
80 {
81 	struct device *dev = NULL;
82 	struct nd_dax *nd_dax;
83 
84 	if (!is_memory(&nd_region->dev))
85 		return NULL;
86 
87 	nd_dax = nd_dax_alloc(nd_region);
88 	if (nd_dax)
89 		dev = nd_pfn_devinit(&nd_dax->nd_pfn, NULL);
90 	__nd_device_register(dev);
91 	return dev;
92 }
93 
94 int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns)
95 {
96 	int rc;
97 	struct nd_dax *nd_dax;
98 	struct device *dax_dev;
99 	struct nd_pfn *nd_pfn;
100 	struct nd_pfn_sb *pfn_sb;
101 	struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
102 
103 	if (ndns->force_raw)
104 		return -ENODEV;
105 
106 	switch (ndns->claim_class) {
107 	case NVDIMM_CCLASS_NONE:
108 	case NVDIMM_CCLASS_DAX:
109 		break;
110 	default:
111 		return -ENODEV;
112 	}
113 
114 	nvdimm_bus_lock(&ndns->dev);
115 	nd_dax = nd_dax_alloc(nd_region);
116 	nd_pfn = &nd_dax->nd_pfn;
117 	dax_dev = nd_pfn_devinit(nd_pfn, ndns);
118 	nvdimm_bus_unlock(&ndns->dev);
119 	if (!dax_dev)
120 		return -ENOMEM;
121 	pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
122 	nd_pfn->pfn_sb = pfn_sb;
123 	rc = nd_pfn_validate(nd_pfn, DAX_SIG);
124 	dev_dbg(dev, "dax: %s\n", rc == 0 ? dev_name(dax_dev) : "<none>");
125 	if (rc < 0) {
126 		nd_detach_ndns(dax_dev, &nd_pfn->ndns);
127 		put_device(dax_dev);
128 	} else
129 		__nd_device_register(dax_dev);
130 
131 	return rc;
132 }
133 EXPORT_SYMBOL(nd_dax_probe);
134