Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2025-01-17 05:45:20 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

swap_info: private to swapfile.c

Browse Source 
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 <hugh.dickins@tiscali.co.uk>
Cc: Nigel Cunningham <ncunningham@crca.org.au>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Hugh Dickins 2009-12-14 17:58:40 -08:00 committed by Linus Torvalds
parent 976d6dfbb0
commit f29ad6a99b
3 changed files with 25 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
include/linux/swap.h
View File

@ -318,9 +318,8 @@ extern void swapcache_free(swp_entry_t, struct page *page);
extern int free_swap_and_cache(swp_entry_t); extern int free_swap_and_cache(swp_entry_t);
extern int swap_type_of(dev_t, sector_t, struct block_device **); extern int swap_type_of(dev_t, sector_t, struct block_device **);
extern unsigned int count_swap_pages(int, int); extern unsigned int count_swap_pages(int, int);
extern sector_t map_swap_page(struct swap_info_struct *, pgoff_t); extern sector_t map_swap_page(swp_entry_t, struct block_device **);
extern sector_t swapdev_block(int, pgoff_t); extern sector_t swapdev_block(int, pgoff_t);
extern struct swap_info_struct *get_swap_info_struct(unsigned);
extern int reuse_swap_page(struct page *); extern int reuse_swap_page(struct page *);
extern int try_to_free_swap(struct page *); extern int try_to_free_swap(struct page *);
struct backing_dev_info; struct backing_dev_info;

19
mm/page_io.c
View File

@ -19,20 +19,17 @@
#include <linux/writeback.h> #include <linux/writeback.h>
#include <asm/pgtable.h> #include <asm/pgtable.h>
static struct bio *get_swap_bio(gfp_t gfp_flags, pgoff_t index, static struct bio *get_swap_bio(gfp_t gfp_flags,
struct page *page, bio_end_io_t end_io) struct page *page, bio_end_io_t end_io)
{ {
struct bio *bio; struct bio *bio;
bio = bio_alloc(gfp_flags, 1); bio = bio_alloc(gfp_flags, 1);
if (bio) { if (bio) {
struct swap_info_struct *sis; swp_entry_t entry;
swp_entry_t entry = { .val = index, }; entry.val = page_private(page);
bio->bi_sector = map_swap_page(entry, &bio->bi_bdev);
sis = get_swap_info_struct(swp_type(entry)); bio->bi_sector <<= PAGE_SHIFT - 9;
bio->bi_sector = map_swap_page(sis, swp_offset(entry)) *
(PAGE_SIZE >> 9);
bio->bi_bdev = sis->bdev;
bio->bi_io_vec[0].bv_page = page; bio->bi_io_vec[0].bv_page = page;
bio->bi_io_vec[0].bv_len = PAGE_SIZE; bio->bi_io_vec[0].bv_len = PAGE_SIZE;
bio->bi_io_vec[0].bv_offset = 0; bio->bi_io_vec[0].bv_offset = 0;
@ -102,8 +99,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
unlock_page(page); unlock_page(page);
goto out; goto out;
} }
bio = get_swap_bio(GFP_NOIO, page_private(page), page, bio = get_swap_bio(GFP_NOIO, page, end_swap_bio_write);
end_swap_bio_write);
if (bio == NULL) { if (bio == NULL) {
set_page_dirty(page); set_page_dirty(page);
unlock_page(page); unlock_page(page);
@ -127,8 +123,7 @@ int swap_readpage(struct page *page)
VM_BUG_ON(!PageLocked(page)); VM_BUG_ON(!PageLocked(page));
VM_BUG_ON(PageUptodate(page)); VM_BUG_ON(PageUptodate(page));
bio = get_swap_bio(GFP_KERNEL, page_private(page), page, bio = get_swap_bio(GFP_KERNEL, page, end_swap_bio_read);
end_swap_bio_read);
if (bio == NULL) { if (bio == NULL) {
unlock_page(page); unlock_page(page);
ret = -ENOMEM; ret = -ENOMEM;

29
mm/swapfile.c
View File

@ -1283,12 +1283,22 @@ static void drain_mmlist(void)
/* /*
* Use this swapdev's extent info to locate the (PAGE_SIZE) block which * 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_info_struct *sis;
struct swap_extent *start_se = se; 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 ( ; ; ) { for ( ; ; ) {
struct list_head *lh; 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) sector_t swapdev_block(int swap_type, pgoff_t offset)
{ {
struct swap_info_struct *sis; struct swap_info_struct *sis;
struct block_device *bdev;
if (swap_type >= nr_swapfiles) if (swap_type >= nr_swapfiles)
return 0; return 0;
sis = swap_info + swap_type; 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 */ #endif /* CONFIG_HIBERNATION */
@ -2159,13 +2171,6 @@ int swapcache_prepare(swp_entry_t entry)
return __swap_duplicate(entry, SWAP_CACHE); 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 * swap_lock prevents swap_map being freed. Don't grab an extra
* reference on the swaphandle, it doesn't matter if it becomes unused. * reference on the swaphandle, it doesn't matter if it becomes unused.