linux_dsm_epyc7002/drivers/dax/pmem/core.c
Christoph Hellwig 1e240e8d4a memremap: move dev_pagemap callbacks into a separate structure
The dev_pagemap is a growing too many callbacks.  Move them into a
separate ops structure so that they are not duplicated for multiple
instances, and an attacker can't easily overwrite them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-07-02 14:32:44 -03:00

72 lines
2.0 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"
struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys)
{
struct resource res;
int rc, id, region_id;
resource_size_t offset;
struct nd_pfn_sb *pfn_sb;
struct dev_dax *dev_dax;
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);
nsio = to_nd_namespace_io(&ndns->dev);
/* parse the 'pfn' info block via ->rw_bytes */
rc = devm_nsio_enable(dev, nsio);
if (rc)
return ERR_PTR(rc);
rc = nvdimm_setup_pfn(nd_pfn, &pgmap);
if (rc)
return ERR_PTR(rc);
devm_nsio_disable(dev, nsio);
/* reserve the metadata area, device-dax will reserve the data */
pfn_sb = nd_pfn->pfn_sb;
offset = le64_to_cpu(pfn_sb->dataoff);
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 resource to the start of data */
memcpy(&res, &pgmap.res, sizeof(res));
res.start += offset;
dax_region = alloc_dax_region(dev, region_id, &res,
nd_region->target_node, le32_to_cpu(pfn_sb->align),
PFN_DEV|PFN_MAP);
if (!dax_region)
return ERR_PTR(-ENOMEM);
dev_dax = __devm_create_dev_dax(dax_region, id, &pgmap, subsys);
/* child dev_dax instances now own the lifetime of the dax_region */
dax_region_put(dax_region);
return dev_dax;
}
EXPORT_SYMBOL_GPL(__dax_pmem_probe);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Intel Corporation");