bio_copy_user — copy user data to bio
struct bio * bio_copy_user
(struct request_queue * q, unsigned long uaddr, unsigned int len, int write_to_vm);
destination block queue
start of user address
length in bytes
bool indicating writing to pages or not
Prepares and returns a bio for indirect user io, bouncing data to/from kernel pages as necessary. Must be paired with call bio_uncopy_user on io completion.