static int submit_extent_page(unsigned int opf, struct extent_io_tree *tree,
                              struct writeback_control *wbc,
                              struct page *page, sector_t sector,
-                             size_t size, unsigned long offset,
+                             size_t size, unsigned long pg_offset,
                              struct block_device *bdev,
                              struct bio **bio_ret,
                              bio_end_io_t end_io_func,
 
                if (prev_bio_flags != bio_flags || !contig ||
                    force_bio_submit ||
-                   merge_bio(tree, page, offset, page_size, bio, bio_flags) ||
-                   bio_add_page(bio, page, page_size, offset) < page_size) {
+                   merge_bio(tree, page, pg_offset, page_size, bio, bio_flags) ||
+                   bio_add_page(bio, page, page_size, pg_offset) < page_size) {
                        ret = submit_one_bio(bio, mirror_num, prev_bio_flags);
                        if (ret < 0) {
                                *bio_ret = NULL;
        }
 
        bio = btrfs_bio_alloc(bdev, (u64)sector << 9);
-       bio_add_page(bio, page, page_size, offset);
+       bio_add_page(bio, page, page_size, pg_offset);
        bio->bi_end_io = end_io_func;
        bio->bi_private = tree;
        bio->bi_write_hint = page->mapping->host->i_write_hint;