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| author | Jens Axboe <axboe@kernel.dk> | 2021-03-02 14:53:21 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-03-02 17:25:46 -0700 |
| commit | caf6912f3f4af7232340d500a4a2008f81b93f14 (patch) | |
| tree | 64099ad5cba8855452bb5eb518da72a5bac3855a /mm/swapfile.c | |
| parent | f5f4fc4649ae542b1a25670b17aaf3cbb6187acc (diff) | |
swap: fix swapfile read/write offset
We're not factoring in the start of the file for where to write and
read the swapfile, which leads to very unfortunate side effects of
writing where we should not be...
Fixes: 48d15436fde6 ("mm: remove get_swap_bio")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'mm/swapfile.c')
| -rw-r--r-- | mm/swapfile.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index f039745989d2..084a5b9a18e5 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -219,6 +219,19 @@ offset_to_swap_extent(struct swap_info_struct *sis, unsigned long offset) BUG(); } +sector_t swap_page_sector(struct page *page) +{ + struct swap_info_struct *sis = page_swap_info(page); + struct swap_extent *se; + sector_t sector; + pgoff_t offset; + + offset = __page_file_index(page); + se = offset_to_swap_extent(sis, offset); + sector = se->start_block + (offset - se->start_page); + return sector << (PAGE_SHIFT - 9); +} + /* * swap allocation tell device that a cluster of swap can now be discarded, * to allow the swap device to optimize its wear-levelling. |