Map user address into bio
struct bio * bio_map_user(struct request_queue * q, struct block_device * bdev, unsigned long uaddr, unsigned int len, int write_to_vm, gfp_t gfp_mask);
q
the struct request_queue for the bio
bdev
destination block device
uaddr
start of user address
len
length in bytes
write_to_vm
bool indicating writing to pages or not
gfp_mask
memory allocation flags
Map the user space address into a bio suitable for io to a block device. Returns an error pointer in case of error.