From f29ad6a99b596b8169744d107bf088e8be9e8d0d Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Mon, 14 Dec 2009 17:58:40 -0800 Subject: swap_info: private to swapfile.c The swap_info_struct is mostly private to mm/swapfile.c, with only one other in-tree user: get_swap_bio(). Adjust its interface to map_swap_page(), so that we can then remove get_swap_info_struct(). But there is a popular user out-of-tree, TuxOnIce: so leave the declaration of swap_info_struct in linux/swap.h. Signed-off-by: Hugh Dickins Cc: Nigel Cunningham Cc: KAMEZAWA Hiroyuki Reviewed-by: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/swapfile.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) (limited to 'mm/swapfile.c') diff --git a/mm/swapfile.c b/mm/swapfile.c index 9c590eef7912..f83f1c6f6196 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1283,12 +1283,22 @@ static void drain_mmlist(void) /* * Use this swapdev's extent info to locate the (PAGE_SIZE) block which - * corresponds to page offset `offset'. + * corresponds to page offset `offset'. Note that the type of this function + * is sector_t, but it returns page offset into the bdev, not sector offset. */ -sector_t map_swap_page(struct swap_info_struct *sis, pgoff_t offset) +sector_t map_swap_page(swp_entry_t entry, struct block_device **bdev) { - struct swap_extent *se = sis->curr_swap_extent; - struct swap_extent *start_se = se; + struct swap_info_struct *sis; + struct swap_extent *start_se; + struct swap_extent *se; + pgoff_t offset; + + sis = swap_info + swp_type(entry); + *bdev = sis->bdev; + + offset = swp_offset(entry); + start_se = sis->curr_swap_extent; + se = start_se; for ( ; ; ) { struct list_head *lh; @@ -1314,12 +1324,14 @@ sector_t map_swap_page(struct swap_info_struct *sis, pgoff_t offset) sector_t swapdev_block(int swap_type, pgoff_t offset) { struct swap_info_struct *sis; + struct block_device *bdev; if (swap_type >= nr_swapfiles) return 0; sis = swap_info + swap_type; - return (sis->flags & SWP_WRITEOK) ? map_swap_page(sis, offset) : 0; + return (sis->flags & SWP_WRITEOK) ? + map_swap_page(swp_entry(swap_type, offset), &bdev) : 0; } #endif /* CONFIG_HIBERNATION */ @@ -2159,13 +2171,6 @@ int swapcache_prepare(swp_entry_t entry) return __swap_duplicate(entry, SWAP_CACHE); } - -struct swap_info_struct * -get_swap_info_struct(unsigned type) -{ - return &swap_info[type]; -} - /* * swap_lock prevents swap_map being freed. Don't grab an extra * reference on the swaphandle, it doesn't matter if it becomes unused. -- cgit v1.2.3-55-g7522