linux-master/fs/dax.c

1477 		ssize_t map_len;
1486 		map_len = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size),
1488 		if (map_len == -EHWPOISON && iov_iter_rw(iter) == WRITE) {
1489 			map_len = dax_direct_access(dax_dev, pgoff,
1492 			if (map_len > 0)
1495 		if (map_len < 0) {
1496 			ret = dax_mem2blk_err(map_len);
1507 		map_len = PFN_PHYS(map_len);
1509 		map_len -= offset;
1510 		if (map_len > end - pos)
1511 			map_len = end - pos;
1515 					map_len, iter);
1518 					map_len, iter);
1521 					map_len, iter);
1529 		if (xfer < map_len)