Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
10struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys)
11{
12 struct resource res;
13 int rc, id, region_id;
14 resource_size_t offset;
15 struct nd_pfn_sb *pfn_sb;
16 struct dev_dax *dev_dax;
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 nsio = to_nd_namespace_io(&ndns->dev);
29
30 /* parse the 'pfn' info block via ->rw_bytes */
31 rc = devm_nsio_enable(dev, nsio);
32 if (rc)
33 return ERR_PTR(rc);
34 rc = nvdimm_setup_pfn(nd_pfn, &pgmap);
35 if (rc)
36 return ERR_PTR(rc);
37 devm_nsio_disable(dev, nsio);
38
39 /* reserve the metadata area, device-dax will reserve the data */
40 pfn_sb = nd_pfn->pfn_sb;
41 offset = le64_to_cpu(pfn_sb->dataoff);
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 resource to the start of data */
53 memcpy(&res, &pgmap.res, sizeof(res));
54 res.start += offset;
55 dax_region = alloc_dax_region(dev, region_id, &res,
56 nd_region->target_node, le32_to_cpu(pfn_sb->align),
57 PFN_DEV|PFN_MAP);
58 if (!dax_region)
59 return ERR_PTR(-ENOMEM);
60
61 dev_dax = __devm_create_dev_dax(dax_region, id, &pgmap, subsys);
62
63 /* child dev_dax instances now own the lifetime of the dax_region */
64 dax_region_put(dax_region);
65
66 return dev_dax;
67}
68EXPORT_SYMBOL_GPL(__dax_pmem_probe);
69
70MODULE_LICENSE("GPL v2");
71MODULE_AUTHOR("Intel Corporation");