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 | |
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: dev->parent); |
24 | |
25 | ndns = nvdimm_namespace_common_probe(dev); |
26 | if (IS_ERR(ptr: ndns)) |
27 | return ERR_CAST(ptr: ndns); |
28 | |
29 | /* parse the 'pfn' info block via ->rw_bytes */ |
30 | rc = devm_namespace_enable(dev, ndns, size: nd_info_block_reserve()); |
31 | if (rc) |
32 | return ERR_PTR(error: rc); |
33 | rc = nvdimm_setup_pfn(nd_pfn, pgmap: &pgmap); |
34 | if (rc) |
35 | return ERR_PTR(error: 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(dev: &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(error: -EBUSY); |
46 | } |
47 | |
48 | rc = sscanf(dev_name(dev: &ndns->dev), "namespace%d.%d" , ®ion_id, &id); |
49 | if (rc != 2) |
50 | return ERR_PTR(error: -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(parent: dev, region_id, range: &range, |
56 | target_node: nd_region->target_node, le32_to_cpu(pfn_sb->align), |
57 | IORESOURCE_DAX_STATIC); |
58 | if (!dax_region) |
59 | return ERR_PTR(error: -ENOMEM); |
60 | |
61 | data = (struct dev_dax_data) { |
62 | .dax_region = dax_region, |
63 | .id = id, |
64 | .pgmap = &pgmap, |
65 | .size = range_len(range: &range), |
66 | }; |
67 | |
68 | return devm_create_dev_dax(data: &data); |
69 | } |
70 | |
71 | static int dax_pmem_probe(struct device *dev) |
72 | { |
73 | return PTR_ERR_OR_ZERO(ptr: __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 | |
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 | |
90 | static void __exit dax_pmem_exit(void) |
91 | { |
92 | driver_unregister(drv: &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 | |