text: // SPDX-License-Identifier: GPL-2.0-only
  /*
   * Copyright (c) 2014-2016, Intel Corporation.
   */
  #include "test/nfit_test.h"
  #include <linux/blkdev.h>
  #include <pmem.h>
  #include <nd.h>
  
  long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
  		long nr_pages, void **kaddr, pfn_t *pfn)
  {
  	resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
  
  	if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512,
  					PFN_PHYS(nr_pages))))
  		return -EIO;
  
  	/*
  	 * Limit dax to a single page at a time given vmalloc()-backed
  	 * in the nfit_test case.
  	 */
  	if (get_nfit_res(pmem->phys_addr + offset)) {
  		struct page *page;
  
  		if (kaddr)
  			*kaddr = pmem->virt_addr + offset;
  		page = vmalloc_to_page(pmem->virt_addr + offset);
  		if (pfn)
  			*pfn = page_to_pfn_t(page);
  		pr_debug_ratelimited("%s: pmem: %p pgoff: %#lx pfn: %#lx\n",
  				__func__, pmem, pgoff, page_to_pfn(page));
  
  		return 1;
  	}
  
  	if (kaddr)
  		*kaddr = pmem->virt_addr + offset;
  	if (pfn)
  		*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
  
  	/*
  	 * If badblocks are present, limit known good range to the
  	 * requested range.
  	 */
  	if (unlikely(pmem->bb.count))
  		return nr_pages;
  	return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
  }
  