1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
/*
* Copyright(c) 2016 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#include <linux/percpu-refcount.h>
#include <linux/memremap.h>
#include <linux/module.h>
#include <linux/pfn_t.h>
#include "../nvdimm/pfn.h"
#include "../nvdimm/nd.h"
#include "dax.h"
struct dax_pmem {
struct device *dev;
struct percpu_ref ref;
struct completion cmp;
};
static struct dax_pmem *to_dax_pmem(struct percpu_ref *ref)
{
return container_of(ref, struct dax_pmem, ref);
}
static void dax_pmem_percpu_release(struct percpu_ref *ref)
{
struct dax_pmem *dax_pmem = to_dax_pmem(ref);
dev_dbg(dax_pmem->dev, "%s\n", __func__);
complete(&dax_pmem->cmp);
}
static void dax_pmem_percpu_exit(void *data)
{
struct percpu_ref *ref = data;
struct dax_pmem *dax_pmem = to_dax_pmem(ref);
dev_dbg(dax_pmem->dev, "%s\n", __func__);
percpu_ref_exit(ref);
}
static void dax_pmem_percpu_kill(void *data)
{
struct percpu_ref *ref = data;
struct dax_pmem *dax_pmem = to_dax_pmem(ref);
dev_dbg(dax_pmem->dev, "%s\n", __func__);
percpu_ref_kill(ref);
wait_for_completion(&dax_pmem->cmp);
}
static int dax_pmem_probe(struct device *dev)
{
int rc;
void *addr;
struct resource res;
struct dax_dev *dax_dev;
struct nd_pfn_sb *pfn_sb;
struct dax_pmem *dax_pmem;
struct nd_region *nd_region;
struct nd_namespace_io *nsio;
struct dax_region *dax_region;
struct nd_namespace_common *ndns;
struct nd_dax *nd_dax = to_nd_dax(dev);
struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
struct vmem_altmap __altmap, *altmap = NULL;
ndns = nvdimm_namespace_common_probe(dev);
if (IS_ERR(ndns))
return PTR_ERR(ndns);
nsio = to_nd_namespace_io(&ndns->dev);
/* parse the 'pfn' info block via ->rw_bytes */
rc = devm_nsio_enable(dev, nsio);
if (rc)
return rc;
altmap = nvdimm_setup_pfn(nd_pfn, &res, &__altmap);
if (IS_ERR(altmap))
return PTR_ERR(altmap);
devm_nsio_disable(dev, nsio);
pfn_sb = nd_pfn->pfn_sb;
if (!devm_request_mem_region(dev, nsio->res.start,
resource_size(&nsio->res),
dev_name(&ndns->dev))) {
dev_warn(dev, "could not reserve region %pR\n", &nsio->res);
return -EBUSY;
}
dax_pmem = devm_kzalloc(dev, sizeof(*dax_pmem), GFP_KERNEL);
if (!dax_pmem)
return -ENOMEM;
dax_pmem->dev = dev;
init_completion(&dax_pmem->cmp);
rc = percpu_ref_init(&dax_pmem->ref, dax_pmem_percpu_release, 0,
GFP_KERNEL);
if (rc)
return rc;
rc = devm_add_action_or_reset(dev, dax_pmem_percpu_exit,
&dax_pmem->ref);
if (rc)
return rc;
addr = devm_memremap_pages(dev, &res, &dax_pmem->ref, altmap);
if (IS_ERR(addr))
return PTR_ERR(addr);
rc = devm_add_action_or_reset(dev, dax_pmem_percpu_kill,
&dax_pmem->ref);
if (rc)
return rc;
/* adjust the dax_region resource to the start of data */
res.start += le64_to_cpu(pfn_sb->dataoff);
nd_region = to_nd_region(dev->parent);
dax_region = alloc_dax_region(dev, nd_region->id, &res,
le32_to_cpu(pfn_sb->align), addr, PFN_DEV|PFN_MAP);
if (!dax_region)
return -ENOMEM;
/* TODO: support for subdividing a dax region... */
dax_dev = devm_create_dax_dev(dax_region, &res, 1);
/* child dax_dev instances now own the lifetime of the dax_region */
dax_region_put(dax_region);
return PTR_ERR_OR_ZERO(dax_dev);
}
static struct nd_device_driver dax_pmem_driver = {
.probe = dax_pmem_probe,
.drv = {
.name = "dax_pmem",
},
.type = ND_DRIVER_DAX_PMEM,
};
static int __init dax_pmem_init(void)
{
return nd_driver_register(&dax_pmem_driver);
}
module_init(dax_pmem_init);
static void __exit dax_pmem_exit(void)
{
driver_unregister(&dax_pmem_driver.drv);
}
module_exit(dax_pmem_exit);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Intel Corporation");
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DAX_PMEM);
|
