xref: /linux/tools/testing/nvdimm/pmem-dax.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
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 }
55