From: Jens Axboe <axboe@suse.de>
Dog slow software suspend found this one. If WB_SYNC_ALL, then you need
to mark the bio as sync as well.
This is because swap_writepage() does a remove_exclusive_swap_page() (going
to __delete_from_swap_cache -> __remove_from_page_cache) which can kill
page->mapping, thus aops->sync_page() has nothing to work with for unplugging
the address space.
---
25-akpm/mm/page_io.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff -puN mm/page_io.c~swap_writepage-BIO_RW_SYNC mm/page_io.c
--- 25/mm/page_io.c~swap_writepage-BIO_RW_SYNC Mon Apr 5 14:17:45 2004
+++ 25-akpm/mm/page_io.c Mon Apr 5 14:17:45 2004
@@ -90,7 +90,7 @@ static int end_swap_bio_read(struct bio
int swap_writepage(struct page *page, struct writeback_control *wbc)
{
struct bio *bio;
- int ret = 0;
+ int ret = 0, rw = WRITE;
if (remove_exclusive_swap_page(page)) {
unlock_page(page);
@@ -103,10 +103,12 @@ int swap_writepage(struct page *page, st
ret = -ENOMEM;
goto out;
}
+ if (wbc->sync_mode == WB_SYNC_ALL)
+ rw |= (1 << BIO_RW_SYNC);
inc_page_state(pswpout);
set_page_writeback(page);
unlock_page(page);
- submit_bio(WRITE, bio);
+ submit_bio(rw, bio);
out:
return ret;
}
_