WSL2-Linux-Kernel/drivers/dax/pmem.c

104 строки
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
#include <linux/memremap.h>
#include <linux/module.h>
#include <linux/pfn_t.h>
#include "../nvdimm/pfn.h"
#include "../nvdimm/nd.h"
#include "bus.h"
static struct dev_dax *__dax_pmem_probe(struct device *dev)
{
struct range range;
int rc, id, region_id;
resource_size_t offset;
struct nd_pfn_sb *pfn_sb;
struct dev_dax *dev_dax;
struct dev_dax_data data;
struct nd_namespace_io *nsio;
struct dax_region *dax_region;
struct dev_pagemap pgmap = { };
struct nd_namespace_common *ndns;
struct nd_dax *nd_dax = to_nd_dax(dev);
struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
struct nd_region *nd_region = to_nd_region(dev->parent);
ndns = nvdimm_namespace_common_probe(dev);
if (IS_ERR(ndns))
return ERR_CAST(ndns);
/* parse the 'pfn' info block via ->rw_bytes */
rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
if (rc)
return ERR_PTR(rc);
rc = nvdimm_setup_pfn(nd_pfn, &pgmap);
if (rc)
return ERR_PTR(rc);
devm_namespace_disable(dev, ndns);
/* reserve the metadata area, device-dax will reserve the data */
pfn_sb = nd_pfn->pfn_sb;
offset = le64_to_cpu(pfn_sb->dataoff);
nsio = to_nd_namespace_io(&ndns->dev);
if (!devm_request_mem_region(dev, nsio->res.start, offset,
dev_name(&ndns->dev))) {
dev_warn(dev, "could not reserve metadata\n");
return ERR_PTR(-EBUSY);
}
rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", &region_id, &id);
if (rc != 2)
return ERR_PTR(-EINVAL);
/* adjust the dax_region range to the start of data */
range = pgmap.range;
range.start += offset;
dax_region = alloc_dax_region(dev, region_id, &range,
nd_region->target_node, le32_to_cpu(pfn_sb->align),
IORESOURCE_DAX_STATIC);
if (!dax_region)
return ERR_PTR(-ENOMEM);
data = (struct dev_dax_data) {
.dax_region = dax_region,
.id = id,
.pgmap = &pgmap,
.size = range_len(&range),
};
dev_dax = devm_create_dev_dax(&data);
/* child dev_dax instances now own the lifetime of the dax_region */
dax_region_put(dax_region);
return dev_dax;
}
static int dax_pmem_probe(struct device *dev)
{
return PTR_ERR_OR_ZERO(__dax_pmem_probe(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);