BLK_RQ_PREP_CLONE(9) Block Devices BLK_RQ_PREP_CLONE(9)
NAME
blk_rq_prep_clone - Helper function to setup clone request
SYNOPSIS
int blk_rq_prep_clone(struct request * rq, struct request * rq_src, struct bio_set * bs, gfp_t gfp_mask,
int (*bio_ctr) (struct bio *, struct bio *, void *), void * data);
ARGUMENTS
rq
the request to be setup
rq_src
original request to be cloned
bs
bio_set that bios for clone are allocated from
gfp_mask
memory allocation mask for bio
bio_ctr
setup function to be called for each clone bio. Returns 0 for success, non 0 for failure.
data
private data to be passed to bio_ctr
DESCRIPTION
Clones bios in rq_src to rq, and copies attributes of rq_src to rq. The actual data parts of rq_src (e.g. ->cmd, ->buffer, ->sense) are not
copied, and copying such parts is the caller's responsibility. Also, pages which the original bios are pointing to are not copied and the
cloned bios just point same pages. So cloned bios must be completed before original bios, which means the caller must complete rq before
rq_src.
COPYRIGHT
Kernel Hackers Manual 2.6. July 2010 BLK_RQ_PREP_CLONE(9)
