Btrfs: Fix typo in extent_io.c

---
Signed-off-by: Chris Mason <chris.mason@oracle.com>

fs/btrfs/extent_io.c

@@ -1416,7 +1416,7 @@ static int end_bio_extent_writepage(struct bio *bio,
 		 * to the correct offsets in the file
 		 */
 		if (state && (state->end + 1 != start ||
-		    !state->state & EXTENT_WRITEBACK)) {
+		    !(state->state & EXTENT_WRITEBACK))) {
 			state = NULL;
 		}
 		spin_unlock_irqrestore(&tree->lock, flags);
@@ -1539,7 +1539,7 @@ static int end_bio_extent_readpage(struct bio *bio,
 		 * to the correct offsets in the file
 		 */
 		if (state && (state->end + 1 != start ||
-		    !state->state & EXTENT_WRITEBACK)) {
+		    !(state->state & EXTENT_LOCKED))) {
 			state = NULL;
 		}
 		spin_unlock_irqrestore(&tree->lock, flags);

fs/btrfs/inode.c

@@ -364,8 +364,7 @@ int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
 	if (btrfs_test_opt(root, NODATASUM) ||
 	    btrfs_test_flag(inode, NODATASUM))
 		return 0;
-
-	if (state->start == start) {
+	if (state && state->start == start) {
 		private = state->private;
 		ret = 0;
 	} else {