diff options
Diffstat (limited to 'mm/swapfile.c')
| -rw-r--r-- | mm/swapfile.c | 52 |
1 files changed, 0 insertions, 52 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index 44595a373e4..b82c028cfcc 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -2288,58 +2288,6 @@ int swapcache_prepare(swp_entry_t entry) } /* - * swap_lock prevents swap_map being freed. Don't grab an extra - * reference on the swaphandle, it doesn't matter if it becomes unused. - */ -int valid_swaphandles(swp_entry_t entry, unsigned long *offset) -{ - struct swap_info_struct *si; - int our_page_cluster = page_cluster; - pgoff_t target, toff; - pgoff_t base, end; - int nr_pages = 0; - - if (!our_page_cluster) /* no readahead */ - return 0; - - si = swap_info[swp_type(entry)]; - target = swp_offset(entry); - base = (target >> our_page_cluster) << our_page_cluster; - end = base + (1 << our_page_cluster); - if (!base) /* first page is swap header */ - base++; - - spin_lock(&swap_lock); - if (end > si->max) /* don't go beyond end of map */ - end = si->max; - - /* Count contiguous allocated slots above our target */ - for (toff = target; ++toff < end; nr_pages++) { - /* Don't read in free or bad pages */ - if (!si->swap_map[toff]) - break; - if (swap_count(si->swap_map[toff]) == SWAP_MAP_BAD) - break; - } - /* Count contiguous allocated slots below our target */ - for (toff = target; --toff >= base; nr_pages++) { - /* Don't read in free or bad pages */ - if (!si->swap_map[toff]) - break; - if (swap_count(si->swap_map[toff]) == SWAP_MAP_BAD) - break; - } - spin_unlock(&swap_lock); - - /* - * Indicate starting offset, and return number of pages to get: - * if only 1, say 0, since there's then no readahead to be done. - */ - *offset = ++toff; - return nr_pages? ++nr_pages: 0; -} - -/* * add_swap_count_continuation - called when a swap count is duplicated * beyond SWAP_MAP_MAX, it allocates a new page and links that to the entry's * page of the original vmalloc'ed swap_map, to hold the continuation count |