path: root/drivers/nvdimm/region_devs.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
 */
#include <linux/scatterlist.h>
#include <linux/memregion.h>
#include <linux/highmem.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/hash.h>
#include <linux/sort.h>
#include <linux/io.h>
#include <linux/nd.h>
#include "nd-core.h"
#include "nd.h"

/*
 * For readq() and writeq() on 32-bit builds, the hi-lo, lo-hi order is
 * irrelevant.
 */
#include <linux/io-64-nonatomic-hi-lo.h>

static DEFINE_PER_CPU(int, flush_idx);

static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm,
		struct nd_region_data *ndrd)
{
	int i, j;

	dev_dbg(dev, "%s: map %d flush address%s\n", nvdimm_name(nvdimm),
			nvdimm->num_flush, nvdimm->num_flush == 1 ? "" : "es");
	for (i = 0; i < (1 << ndrd->hints_shift); i++) {
		struct resource *res = &nvdimm->flush_wpq[i];
		unsigned long pfn = PHYS_PFN(res->start);
		void __iomem *flush_page;

		/* check if flush hints share a page */
		for (j = 0; j < i; j++) {
			struct resource *res_j = &nvdimm->flush_wpq[j];
			unsigned long pfn_j = PHYS_PFN(res_j->start);

			if (pfn == pfn_j)
				break;
		}

		if (j < i)
			flush_page = (void __iomem *) ((unsigned long)
					ndrd_get_flush_wpq(ndrd, dimm, j)
					& PAGE_MASK);
		else
			flush_page = devm_nvdimm_ioremap(dev,
					PFN_PHYS(pfn), PAGE_SIZE);
		if (!flush_page)
			return -ENXIO;
		ndrd_set_flush_wpq(ndrd, dimm, i, flush_page
				+ (res->start & ~PAGE_MASK));
	}

	return 0;
}

int nd_region_activate(struct nd_region *nd_region)
{
	int i, j, num_flush = 0;
	struct nd_region_data *ndrd;
	struct device *dev = &nd_region->dev;
	size_t flush_data_size = sizeof(void *);

	nvdimm_bus_lock(&nd_region->dev);
	for (i = 0; i < nd_region->ndr_mappings; i++) {
		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
		struct nvdimm *nvdimm = nd_mapping->nvdimm;

		if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
			nvdimm_bus_unlock(&nd_region->dev);
			return -EBUSY;
		}

		/* at least one null hint slot per-dimm for the "no-hint" case */
		flush_data_size += sizeof(void *);
		num_flush = min_not_zero(num_flush, nvdimm->num_flush);
		if (!nvdimm->num_flush)
			continue;
		flush_data_size += nvdimm->num_flush * sizeof(void *);
	}
	nvdimm_bus_unlock(&nd_region->dev);

	ndrd = devm_kzalloc(dev, sizeof(*ndrd) + flush_data_size, GFP_KERNEL);
	if (!ndrd)
		return -ENOMEM;
	dev_set_drvdata(dev, ndrd);

	if (!num_flush)
		return 0;

	ndrd->hints_shift = ilog2(num_flush);
	for (i = 0; i < nd_region->ndr_mappings; i++) {
		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
		struct nvdimm *nvdimm = nd_mapping->nvdimm;
		int rc = nvdimm_map_flush(