-static struct block_device *resume_bdev;
-
-/**
- * submit - submit BIO request.
- * @rw: READ or WRITE.
- * @off physical offset of page.
- * @page: page we're reading or writing.
- * @bio_chain: list of pending biod (for async reading)
- *
- * Straight from the textbook - allocate and initialize the bio.
- * If we're reading, make sure the page is marked as dirty.
- * Then submit it and, if @bio_chain == NULL, wait.
- */
-static int submit(int rw, pgoff_t page_off, struct page *page,
- struct bio **bio_chain)
-{
- const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
- struct bio *bio;
-
- bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
- bio->bi_sector = page_off * (PAGE_SIZE >> 9);
- bio->bi_bdev = resume_bdev;
- bio->bi_end_io = end_swap_bio_read;
-
- if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
- printk(KERN_ERR "PM: Adding page to bio failed at %ld\n",
- page_off);
- bio_put(bio);
- return -EFAULT;
- }
-
- lock_page(page);
- bio_get(bio);
-
- if (bio_chain == NULL) {
- submit_bio(bio_rw, bio);
- wait_on_page_locked(page);
- if (rw == READ)
- bio_set_pages_dirty(bio);
- bio_put(bio);
- } else {
- if (rw == READ)
- get_page(page); /* These pages are freed later */
- bio->bi_private = *bio_chain;
- *bio_chain = bio;
- submit_bio(bio_rw, bio);
- }
- return 0;
-}
-
-static int bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
-{
- return submit(READ, page_off, virt_to_page(addr), bio_chain);
-}
-
-static int bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
-{
- return submit(WRITE, page_off, virt_to_page(addr), bio_chain);
-}
-
-static int wait_on_bio_chain(struct bio **bio_chain)
-{
- struct bio *bio;
- struct bio *next_bio;
- int ret = 0;
-
- if (bio_chain == NULL)
- return 0;
-
- bio = *bio_chain;
- if (bio == NULL)
- return 0;
- while (bio) {
- struct page *page;
-
- next_bio = bio->bi_private;
- page = bio->bi_io_vec[0].bv_page;
- wait_on_page_locked(page);
- if (!PageUptodate(page) || PageError(page))
- ret = -EIO;
- put_page(page);
- bio_put(bio);
- bio = next_bio;
- }
- *bio_chain = NULL;
- return ret;
-}