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 block_device *bdev, sector_t sector,
  19                 void **kaddr, pfn_t *pfn, long size)
  20 {
  21         struct pmem_device *pmem = bdev->bd_queue->queuedata;
  22         resource_size_t offset = sector * 512 + pmem->data_offset;
  23
  24         if (unlikely(is_bad_pmem(&pmem->bb, sector, size)))
  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                 *kaddr = pmem->virt_addr + offset;
  35                 page = vmalloc_to_page(pmem->virt_addr + offset);
  36                 *pfn = page_to_pfn_t(page);
  37                 dev_dbg_ratelimited(disk_to_dev(bdev->bd_disk)->parent,
  38                                 "%s: sector: %#llx pfn: %#lx\n", __func__,
  39                                 (unsigned long long) sector, page_to_pfn(page));
  40
  41                 return PAGE_SIZE;
  42         }
  43
  44         *kaddr = pmem->virt_addr + offset;
  45         *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
  46
  47         /*
  48          * If badblocks are present, limit known good range to the
  49          * requested range.
  50          */
  51         if (unlikely(pmem->bb.count))
  52                 return size;
  53         return pmem->size - pmem->pfn_pad - offset;
  54 }