bio_copy_kern — copy kernel address into bio
struct bio * bio_copy_kern
(struct request_queue * q, void * data, unsigned int len, gfp_t gfp_mask, int reading);
the struct request_queue for the bio
pointer to buffer to copy
length in bytes
allocation flags for bio and page allocation
data direction is READ
copy the kernel address into a bio suitable for io to a block device. Returns an error pointer in case of error.