block: unexport bio_clone_bioset

Now only used by the bounce code, so move it there and mark the function
static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2018-07-24 09:52:34 +02:00 коммит произвёл Jens Axboe
Родитель 3ed122e68b
Коммит c55183c9aa
3 изменённых файлов: 68 добавлений и 79 удалений

Просмотреть файл

@ -646,83 +646,6 @@ struct bio *bio_clone_fast(struct bio *bio, gfp_t gfp_mask, struct bio_set *bs)
}
EXPORT_SYMBOL(bio_clone_fast);
/**
* bio_clone_bioset - clone a bio
* @bio_src: bio to clone
* @gfp_mask: allocation priority
* @bs: bio_set to allocate from
*
* Clone bio. Caller will own the returned bio, but not the actual data it
* points to. Reference count of returned bio will be one.
*/
struct bio *bio_clone_bioset(struct bio *bio_src, gfp_t gfp_mask,
struct bio_set *bs)
{
struct bvec_iter iter;
struct bio_vec bv;
struct bio *bio;
/*
* Pre immutable biovecs, __bio_clone() used to just do a memcpy from
* bio_src->bi_io_vec to bio->bi_io_vec.
*
* We can't do that anymore, because:
*
* - The point of cloning the biovec is to produce a bio with a biovec
* the caller can modify: bi_idx and bi_bvec_done should be 0.
*
* - The original bio could've had more than BIO_MAX_PAGES biovecs; if
* we tried to clone the whole thing bio_alloc_bioset() would fail.
* But the clone should succeed as long as the number of biovecs we
* actually need to allocate is fewer than BIO_MAX_PAGES.
*
* - Lastly, bi_vcnt should not be looked at or relied upon by code
* that does not own the bio - reason being drivers don't use it for
* iterating over the biovec anymore, so expecting it to be kept up
* to date (i.e. for clones that share the parent biovec) is just
* asking for trouble and would force extra work on
* __bio_clone_fast() anyways.
*/
bio = bio_alloc_bioset(gfp_mask, bio_segments(bio_src), bs);
if (!bio)
return NULL;
bio->bi_disk = bio_src->bi_disk;
bio->bi_opf = bio_src->bi_opf;
bio->bi_write_hint = bio_src->bi_write_hint;
bio->bi_iter.bi_sector = bio_src->bi_iter.bi_sector;
bio->bi_iter.bi_size = bio_src->bi_iter.bi_size;
switch (bio_op(bio)) {
case REQ_OP_DISCARD:
case REQ_OP_SECURE_ERASE:
case REQ_OP_WRITE_ZEROES:
break;
case REQ_OP_WRITE_SAME:
bio->bi_io_vec[bio->bi_vcnt++] = bio_src->bi_io_vec[0];
break;
default:
bio_for_each_segment(bv, bio_src, iter)
bio->bi_io_vec[bio->bi_vcnt++] = bv;
break;
}
if (bio_integrity(bio_src)) {
int ret;
ret = bio_integrity_clone(bio, bio_src, gfp_mask);
if (ret < 0) {
bio_put(bio);
return NULL;
}
}
bio_clone_blkcg_association(bio, bio_src);
return bio;
}
EXPORT_SYMBOL(bio_clone_bioset);
/**
* bio_add_pc_page - attempt to add page to bio
* @q: the target queue

Просмотреть файл

@ -195,6 +195,73 @@ static void bounce_end_io_read_isa(struct bio *bio)
__bounce_end_io_read(bio, &isa_page_pool);
}
static struct bio *bounce_clone_bio(struct bio *bio_src, gfp_t gfp_mask,
struct bio_set *bs)
{
struct bvec_iter iter;
struct bio_vec bv;
struct bio *bio;
/*
* Pre immutable biovecs, __bio_clone() used to just do a memcpy from
* bio_src->bi_io_vec to bio->bi_io_vec.
*
* We can't do that anymore, because:
*
* - The point of cloning the biovec is to produce a bio with a biovec
* the caller can modify: bi_idx and bi_bvec_done should be 0.
*
* - The original bio could've had more than BIO_MAX_PAGES biovecs; if
* we tried to clone the whole thing bio_alloc_bioset() would fail.
* But the clone should succeed as long as the number of biovecs we
* actually need to allocate is fewer than BIO_MAX_PAGES.
*
* - Lastly, bi_vcnt should not be looked at or relied upon by code
* that does not own the bio - reason being drivers don't use it for
* iterating over the biovec anymore, so expecting it to be kept up
* to date (i.e. for clones that share the parent biovec) is just
* asking for trouble and would force extra work on
* __bio_clone_fast() anyways.
*/
bio = bio_alloc_bioset(gfp_mask, bio_segments(bio_src), bs);
if (!bio)
return NULL;
bio->bi_disk = bio_src->bi_disk;
bio->bi_opf = bio_src->bi_opf;
bio->bi_write_hint = bio_src->bi_write_hint;
bio->bi_iter.bi_sector = bio_src->bi_iter.bi_sector;
bio->bi_iter.bi_size = bio_src->bi_iter.bi_size;
switch (bio_op(bio)) {
case REQ_OP_DISCARD:
case REQ_OP_SECURE_ERASE:
case REQ_OP_WRITE_ZEROES:
break;
case REQ_OP_WRITE_SAME:
bio->bi_io_vec[bio->bi_vcnt++] = bio_src->bi_io_vec[0];
break;
default:
bio_for_each_segment(bv, bio_src, iter)
bio->bi_io_vec[bio->bi_vcnt++] = bv;
break;
}
if (bio_integrity(bio_src)) {
int ret;
ret = bio_integrity_clone(bio, bio_src, gfp_mask);
if (ret < 0) {
bio_put(bio);
return NULL;
}
}
bio_clone_blkcg_association(bio, bio_src);
return bio;
}
static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
mempool_t *pool)
{
@ -222,7 +289,7 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
generic_make_request(*bio_orig);
*bio_orig = bio;
}
bio = bio_clone_bioset(*bio_orig, GFP_NOIO, passthrough ? NULL :
bio = bounce_clone_bio(*bio_orig, GFP_NOIO, passthrough ? NULL :
&bounce_bio_set);
bio_for_each_segment_all(to, bio, i) {

Просмотреть файл

@ -429,7 +429,6 @@ extern void bio_put(struct bio *);
extern void __bio_clone_fast(struct bio *, struct bio *);
extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
extern struct bio_set fs_bio_set;