btrfs: remove unused parameter from submit_extent_page

This used to hold number of maximum pages to allocate, but this is now
limited by BIO_MAX_PAGES. The local are now unused and removed as well.
Reviewed-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

fs/btrfs/extent_io.c

@@ -2759,7 +2759,6 @@ static int submit_extent_page(int op, int op_flags, struct extent_io_tree *tree,
 			      size_t size, unsigned long offset,
 			      struct block_device *bdev,
 			      struct bio **bio_ret,
-			      unsigned long max_pages,
 			      bio_end_io_t end_io_func,
 			      int mirror_num,
 			      unsigned long prev_bio_flags,
@@ -2925,7 +2924,6 @@ static int __do_readpage(struct extent_io_tree *tree,
 		}
 	}
 	while (cur <= end) {
-		unsigned long pnr = (last_byte >> PAGE_SHIFT) + 1;
 		bool force_bio_submit = false;
 
 		if (cur >= last_byte) {
@@ -3060,10 +3058,9 @@ static int __do_readpage(struct extent_io_tree *tree,
 			continue;
 		}
 
-		pnr -= page->index;
 		ret = submit_extent_page(REQ_OP_READ, read_flags, tree, NULL,
 					 page, sector, disk_io_size, pg_offset,
-					 bdev, bio, pnr,
+					 bdev, bio,
 					 end_bio_extent_readpage, mirror_num,
 					 *bio_flags,
 					 this_bio_flag,
@@ -3366,7 +3363,6 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode,
 
 	while (cur <= end) {
 		u64 em_end;
-		unsigned long max_nr;
 
 		if (cur >= i_size) {
 			if (tree->ops && tree->ops->writepage_end_io_hook)
@@ -3423,8 +3419,6 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode,
 			continue;
 		}
 
-		max_nr = (i_size >> PAGE_SHIFT) + 1;
-
 		set_range_writeback(tree, cur, cur + iosize - 1);
 		if (!PageWriteback(page)) {
 			btrfs_err(BTRFS_I(inode)->root->fs_info,
@@ -3434,7 +3428,7 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode,
 
 		ret = submit_extent_page(REQ_OP_WRITE, write_flags, tree, wbc,
 					 page, sector, iosize, pg_offset,
-					 bdev, &epd->bio, max_nr,
+					 bdev, &epd->bio,
 					 end_bio_extent_writepage,
 					 0, 0, 0, false);
 		if (ret) {
@@ -3751,7 +3745,7 @@ static noinline_for_stack int write_one_eb(struct extent_buffer *eb,
 		set_page_writeback(p);
 		ret = submit_extent_page(REQ_OP_WRITE, write_flags, tree, wbc,
 					 p, offset >> 9, PAGE_SIZE, 0, bdev,
-					 &epd->bio, -1,
+					 &epd->bio,
 					 end_bio_extent_buffer_writepage,
 					 0, epd->bio_flags, bio_flags, false);
 		epd->bio_flags = bio_flags;