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 
nd_dax_release(struct device * dev)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 
to_nd_dax(struct device * dev)26 struct nd_dax *to_nd_dax(struct device *dev)
27 {
28 	struct nd_dax *nd_dax = container_of(dev, struct nd_dax, nd_pfn.dev);
29 
30 	WARN_ON(!is_nd_dax(dev));
31 	return nd_dax;
32 }
33 EXPORT_SYMBOL(to_nd_dax);
34 
35 static const struct device_type nd_dax_device_type = {
36 	.name = "nd_dax",
37 	.release = nd_dax_release,
38 	.groups = nd_pfn_attribute_groups,
39 };
40 
is_nd_dax(struct device * dev)41 bool is_nd_dax(struct device *dev)
42 {
43 	return dev ? dev->type == &nd_dax_device_type : false;
44 }
45 EXPORT_SYMBOL(is_nd_dax);
46 
nd_dax_alloc(struct nd_region * nd_region)47 static struct nd_dax *nd_dax_alloc(struct nd_region *nd_region)
48 {
49 	struct nd_pfn *nd_pfn;
50 	struct nd_dax *nd_dax;
51 	struct device *dev;
52 
53 	nd_dax = kzalloc(sizeof(*nd_dax), GFP_KERNEL);
54 	if (!nd_dax)
55 		return NULL;
56 
57 	nd_pfn = &nd_dax->nd_pfn;
58 	nd_pfn->id = ida_simple_get(&nd_region->dax_ida, 0, 0, GFP_KERNEL);
59 	if (nd_pfn->id < 0) {
60 		kfree(nd_dax);
61 		return NULL;
62 	}
63 
64 	dev = &nd_pfn->dev;
65 	dev_set_name(dev, "dax%d.%d", nd_region->id, nd_pfn->id);
66 	dev->type = &nd_dax_device_type;
67 	dev->parent = &nd_region->dev;
68 
69 	return nd_dax;
70 }
71 
nd_dax_create(struct nd_region * nd_region)72 struct device *nd_dax_create(struct nd_region *nd_region)
73 {
74 	struct device *dev = NULL;
75 	struct nd_dax *nd_dax;
76 
77 	if (!is_memory(&nd_region->dev))
78 		return NULL;
79 
80 	nd_dax = nd_dax_alloc(nd_region);
81 	if (nd_dax)
82 		dev = nd_pfn_devinit(&nd_dax->nd_pfn, NULL);
83 	nd_device_register(dev);
84 	return dev;
85 }
86 
nd_dax_probe(struct device * dev,struct nd_namespace_common * ndns)87 int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns)
88 {
89 	int rc;
90 	struct nd_dax *nd_dax;
91 	struct device *dax_dev;
92 	struct nd_pfn *nd_pfn;
93 	struct nd_pfn_sb *pfn_sb;
94 	struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
95 
96 	if (ndns->force_raw)
97 		return -ENODEV;
98 
99 	switch (ndns->claim_class) {
100 	case NVDIMM_CCLASS_NONE:
101 	case NVDIMM_CCLASS_DAX:
102 		break;
103 	default:
104 		return -ENODEV;
105 	}
106 
107 	nvdimm_bus_lock(&ndns->dev);
108 	nd_dax = nd_dax_alloc(nd_region);
109 	nd_pfn = &nd_dax->nd_pfn;
110 	dax_dev = nd_pfn_devinit(nd_pfn, ndns);
111 	nvdimm_bus_unlock(&ndns->dev);
112 	if (!dax_dev)
113 		return -ENOMEM;
114 	pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
115 	nd_pfn->pfn_sb = pfn_sb;
116 	rc = nd_pfn_validate(nd_pfn, DAX_SIG);
117 	dev_dbg(dev, "dax: %s\n", rc == 0 ? dev_name(dax_dev) : "<none>");
118 	if (rc < 0) {
119 		nd_detach_ndns(dax_dev, &nd_pfn->ndns);
120 		put_device(dax_dev);
121 	} else
122 		nd_device_register(dax_dev);
123 
124 	return rc;
125 }
126 EXPORT_SYMBOL(nd_dax_probe);
127