From 3a291a20bd6fcfafb2109031f0760a0d3e92ecd7 Mon Sep 17 00:00:00 2001 From: Rafael J. Wysocki Date: Fri, 6 Jan 2006 00:16:37 -0800 Subject: [PATCH] mm: add a new function (needed for swap suspend) This adds the function get_swap_page_of_type() allowing us to specify an index in swap_info[] and select a swap_info_struct structure to be used for allocating a swap page. This function (or another one of similar functionality) will be necessary for implementing the image-writing part of swsusp in the user space.  It can also be used for simplifying the current in-kernel implementation of the image-writing part of swsusp. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/swapfile.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'mm') diff --git a/mm/swapfile.c b/mm/swapfile.c index edafeace301f..6da4b28b896b 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -211,6 +211,26 @@ noswap: return (swp_entry_t) {0}; } +swp_entry_t get_swap_page_of_type(int type) +{ + struct swap_info_struct *si; + pgoff_t offset; + + spin_lock(&swap_lock); + si = swap_info + type; + if (si->flags & SWP_WRITEOK) { + nr_swap_pages--; + offset = scan_swap_map(si); + if (offset) { + spin_unlock(&swap_lock); + return swp_entry(type, offset); + } + nr_swap_pages++; + } + spin_unlock(&swap_lock); + return (swp_entry_t) {0}; +} + static struct swap_info_struct * swap_info_get(swp_entry_t entry) { struct swap_info_struct * p; -- cgit v1.2.3