tools/testing/nvdimm/pmem-dax.c

   1 /*
   2  * Copyright (c) 2014-2016, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  */
  13 #include "test/nfit_test.h"
  14 #include <linux/blkdev.h>
  15 #include <pmem.h>
  16 #include <nd.h>
  17
  18 long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
  19                 long nr_pages, void **kaddr, pfn_t *pfn)
  20 {
  21         resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
  22
  23         if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512,
  24                                         PFN_PHYS(nr_pages))))
  25                 return -EIO;
  26
  27         /*
  28          * Limit dax to a single page at a time given vmalloc()-backed
  29          * in the nfit_test case.
  30          */
  31         if (get_nfit_res(pmem->phys_addr + offset)) {
  32                 struct page *page;
  33
  34                 if (kaddr)
  35                         *kaddr = pmem->virt_addr + offset;
  36                 page = vmalloc_to_page(pmem->virt_addr + offset);
  37                 if (pfn)
  38                         *pfn = page_to_pfn_t(page);
  39                 pr_debug_ratelimited("%s: pmem: %p pgoff: %#lx pfn: %#lx\n",
  40                                 __func__, pmem, pgoff, page_to_pfn(page));
  41
  42                 return 1;
  43         }
  44
  45         if (kaddr)
  46                 *kaddr = pmem->virt_addr + offset;
  47         if (pfn)
  48                 *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
  49
  50         /*
  51          * If badblocks are present, limit known good range to the
  52          * requested range.
  53          */
  54         if (unlikely(pmem->bb.count))
  55                 return nr_pages;
  56         return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
  57 }