1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
3 #include <linux/memremap.h>
4 #include <linux/module.h>
5 #include <linux/pfn_t.h>
6 #include "../nvdimm/pfn.h"
7 #include "../nvdimm/nd.h"
8 #include "bus.h"
9
__dax_pmem_probe(struct device * dev)10 static struct dev_dax *__dax_pmem_probe(struct device *dev)
11 {
12 struct range range;
13 int rc, id, region_id;
14 resource_size_t offset;
15 struct nd_pfn_sb *pfn_sb;
16 struct dev_dax_data data;
17 struct nd_namespace_io *nsio;
18 struct dax_region *dax_region;
19 struct dev_pagemap pgmap = { };
20 struct nd_namespace_common *ndns;
21 struct nd_dax *nd_dax = to_nd_dax(dev);
22 struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
23 struct nd_region *nd_region = to_nd_region(dev->parent);
24
25 ndns = nvdimm_namespace_common_probe(dev);
26 if (IS_ERR(ndns))
27 return ERR_CAST(ndns);
28
29 /* parse the 'pfn' info block via ->rw_bytes */
30 rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
31 if (rc)
32 return ERR_PTR(rc);
33 rc = nvdimm_setup_pfn(nd_pfn, &pgmap);
34 if (rc)
35 return ERR_PTR(rc);
36 devm_namespace_disable(dev, ndns);
37
38 /* reserve the metadata area, device-dax will reserve the data */
39 pfn_sb = nd_pfn->pfn_sb;
40 offset = le64_to_cpu(pfn_sb->dataoff);
41 nsio = to_nd_namespace_io(&ndns->dev);
42 if (!devm_request_mem_region(dev, nsio->res.start, offset,
43 dev_name(&ndns->dev))) {
44 dev_warn(dev, "could not reserve metadata\n");
45 return ERR_PTR(-EBUSY);
46 }
47
48 rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", ®ion_id, &id);
49 if (rc != 2)
50 return ERR_PTR(-EINVAL);
51
52 /* adjust the dax_region range to the start of data */
53 range = pgmap.range;
54 range.start += offset;
55 dax_region = alloc_dax_region(dev, region_id, &range,
56 nd_region->target_node, le32_to_cpu(pfn_sb->align),
57 IORESOURCE_DAX_STATIC);
58 if (!dax_region)
59 return ERR_PTR(-ENOMEM);
60
61 data = (struct dev_dax_data) {
62 .dax_region = dax_region,
63 .id = id,
64 .pgmap = &pgmap,
65 .size = range_len(&range),
66 };
67
68 return devm_create_dev_dax(&data);
69 }
70
dax_pmem_probe(struct device * dev)71 static int dax_pmem_probe(struct device *dev)
72 {
73 return PTR_ERR_OR_ZERO(__dax_pmem_probe(dev));
74 }
75
76 static struct nd_device_driver dax_pmem_driver = {
77 .probe = dax_pmem_probe,
78 .drv = {
79 .name = "dax_pmem",
80 },
81 .type = ND_DRIVER_DAX_PMEM,
82 };
83
dax_pmem_init(void)84 static int __init dax_pmem_init(void)
85 {
86 return nd_driver_register(&dax_pmem_driver);
87 }
88 module_init(dax_pmem_init);
89
dax_pmem_exit(void)90 static void __exit dax_pmem_exit(void)
91 {
92 driver_unregister(&dax_pmem_driver.drv);
93 }
94 module_exit(dax_pmem_exit);
95
96 MODULE_LICENSE("GPL v2");
97 MODULE_AUTHOR("Intel Corporation");
98 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DAX_PMEM);
99