BIO_GET_NR_VECS(9) The Linux VFS BIO_GET_NR_VECS(9)
NAME bio_get_nr_vecs - return approx number of vecs
SYNOPSIS int bio_get_nr_vecs(struct block_device * bdev);
ARGUMENTS bdev I/O target
DESCRIPTION Return the approximate number of pages we can send to this target. There´s no guarantee that you will be able to fit this number of pages into a bio, it does not account for dynamic restrictions that vary on offset.
COPYRIGHT Kernel Hackers Manual 2.6. April 2016 BIO_GET_NR_VECS(9)