static void req_bio_endio(struct request *rq, struct bio *bio,
unsigned int nbytes, int error)
{
- if (error && !(rq->cmd_flags & REQ_CLONE))
+ if (error)
clear_bit(BIO_UPTODATE, &bio->bi_flags);
else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
error = -EIO;
bio_advance(bio, nbytes);
/* don't actually finish bio if it's part of flush sequence */
- if (bio->bi_iter.bi_size == 0 &&
- !(rq->cmd_flags & (REQ_FLUSH_SEQ|REQ_CLONE)))
+ if (bio->bi_iter.bi_size == 0 && !(rq->cmd_flags & REQ_FLUSH_SEQ))
bio_endio(bio, error);
}
}
EXPORT_SYMBOL_GPL(blk_lld_busy);
-void blk_rq_prep_clone(struct request *dst, struct request *src)
+/**
+ * blk_rq_unprep_clone - Helper function to free all bios in a cloned request
+ * @rq: the clone request to be cleaned up
+ *
+ * Description:
+ * Free all bios in @rq for a cloned request.
+ */
+void blk_rq_unprep_clone(struct request *rq)
+{
+ struct bio *bio;
+
+ while ((bio = rq->bio) != NULL) {
+ rq->bio = bio->bi_next;
+
+ bio_put(bio);
+ }
+}
+EXPORT_SYMBOL_GPL(blk_rq_unprep_clone);
+
+/*
+ * Copy attributes of the original request to the clone request.
+ * The actual data parts (e.g. ->cmd, ->sense) are not copied.
+ */
+static void __blk_rq_prep_clone(struct request *dst, struct request *src)
{
dst->cpu = src->cpu;
- dst->cmd_flags |= (src->cmd_flags & REQ_CLONE_MASK);
- dst->cmd_flags |= REQ_NOMERGE | REQ_CLONE;
+ dst->cmd_flags |= (src->cmd_flags & REQ_CLONE_MASK) | REQ_NOMERGE;
dst->cmd_type = src->cmd_type;
dst->__sector = blk_rq_pos(src);
dst->__data_len = blk_rq_bytes(src);
dst->nr_phys_segments = src->nr_phys_segments;
dst->ioprio = src->ioprio;
dst->extra_len = src->extra_len;
- dst->bio = src->bio;
- dst->biotail = src->biotail;
- dst->cmd = src->cmd;
- dst->cmd_len = src->cmd_len;
- dst->sense = src->sense;
+}
+
+/**
+ * blk_rq_prep_clone - Helper function to setup clone request
+ * @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, ->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.
+ */
+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)
+{
+ struct bio *bio, *bio_src;
+
+ if (!bs)
+ bs = fs_bio_set;
+
+ __rq_for_each_bio(bio_src, rq_src) {
+ bio = bio_clone_fast(bio_src, gfp_mask, bs);
+ if (!bio)
+ goto free_and_out;
+
+ if (bio_ctr && bio_ctr(bio, bio_src, data))
+ goto free_and_out;
+
+ if (rq->bio) {
+ rq->biotail->bi_next = bio;
+ rq->biotail = bio;
+ } else
+ rq->bio = rq->biotail = bio;
+ }
+
+ __blk_rq_prep_clone(rq, rq_src);
+
+ return 0;
+
+free_and_out:
+ if (bio)
+ bio_put(bio);
+ blk_rq_unprep_clone(rq);
+
+ return -ENOMEM;
}
EXPORT_SYMBOL_GPL(blk_rq_prep_clone);
dec_pending(io, error);
}
+/*
+ * Partial completion handling for request-based dm
+ */
+static void end_clone_bio(struct bio *clone, int error)
+{
+ struct dm_rq_clone_bio_info *info =
+ container_of(clone, struct dm_rq_clone_bio_info, clone);
+ struct dm_rq_target_io *tio = info->tio;
+ struct bio *bio = info->orig;
+ unsigned int nr_bytes = info->orig->bi_iter.bi_size;
+
+ bio_put(clone);
+
+ if (tio->error)
+ /*
+ * An error has already been detected on the request.
+ * Once error occurred, just let clone->end_io() handle
+ * the remainder.
+ */
+ return;
+ else if (error) {
+ /*
+ * Don't notice the error to the upper layer yet.
+ * The error handling decision is made by the target driver,
+ * when the request is completed.
+ */
+ tio->error = error;
+ return;
+ }
+
+ /*
+ * I/O for the bio successfully completed.
+ * Notice the data completion to the upper layer.
+ */
+
+ /*
+ * bios are processed from the head of the list.
+ * So the completing bio should always be rq->bio.
+ * If it's not, something wrong is happening.
+ */
+ if (tio->orig->bio != bio)
+ DMERR("bio completion is going in the middle of the request");
+
+ /*
+ * Update the original request.
+ * Do not use blk_end_request() here, because it may complete
+ * the original request before the clone, and break the ordering.
+ */
+ blk_update_request(tio->orig, 0, nr_bytes);
+}
+
static struct dm_rq_target_io *tio_from_request(struct request *rq)
{
return (rq->q->mq_ops ? blk_mq_rq_to_pdu(rq) : rq->special);
struct dm_rq_target_io *tio = clone->end_io_data;
struct mapped_device *md = tio->md;
+ blk_rq_unprep_clone(clone);
+
if (md->type == DM_TYPE_MQ_REQUEST_BASED)
/* stacked on blk-mq queue(s) */
tio->ti->type->release_clone_rq(clone);
dm_complete_request(rq, r);
}
-static void setup_clone(struct request *clone, struct request *rq,
- struct dm_rq_target_io *tio)
+static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
+ void *data)
{
- blk_rq_prep_clone(clone, rq);
+ struct dm_rq_target_io *tio = data;
+ struct dm_rq_clone_bio_info *info =
+ container_of(bio, struct dm_rq_clone_bio_info, clone);
+
+ info->orig = bio_orig;
+ info->tio = tio;
+ bio->bi_end_io = end_clone_bio;
+
+ return 0;
+}
+
+static int setup_clone(struct request *clone, struct request *rq,
+ struct dm_rq_target_io *tio, gfp_t gfp_mask)
+{
+ int r;
+
+ r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask,
+ dm_rq_bio_constructor, tio);
+ if (r)
+ return r;
+
+ clone->cmd = rq->cmd;
+ clone->cmd_len = rq->cmd_len;
+ clone->sense = rq->sense;
clone->end_io = end_clone_request;
clone->end_io_data = tio;
+
tio->clone = clone;
+
+ return 0;
}
static struct request *clone_rq(struct request *rq, struct mapped_device *md,
clone = tio->clone;
blk_rq_init(NULL, clone);
- setup_clone(clone, rq, tio);
+ if (setup_clone(clone, rq, tio, gfp_mask)) {
+ /* -ENOMEM */
+ if (alloc_clone)
+ free_clone_request(md, clone);
+ return NULL;
+ }
return clone;
}
}
if (r != DM_MAPIO_REMAPPED)
return r;
- setup_clone(clone, rq, tio);
+ if (setup_clone(clone, rq, tio, GFP_ATOMIC)) {
+ /* -ENOMEM */
+ ti->type->release_clone_rq(clone);
+ return DM_MAPIO_REQUEUE;
+ }
}
switch (r) {
goto out;
}
+ BUG_ON(!p || md->io_pool || md->rq_pool || md->bs);
+
md->io_pool = p->io_pool;
p->io_pool = NULL;
md->rq_pool = p->rq_pool;
}
EXPORT_SYMBOL_GPL(dm_noflush_suspending);
-struct dm_md_mempools *dm_alloc_bio_mempools(unsigned integrity,
- unsigned per_bio_data_size)
+struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, unsigned type,
+ unsigned integrity, unsigned per_bio_data_size)
{
- struct dm_md_mempools *pools;
- unsigned int pool_size = dm_get_reserved_bio_based_ios();
+ struct dm_md_mempools *pools = kzalloc(sizeof(*pools), GFP_KERNEL);
+ struct kmem_cache *cachep = NULL;
+ unsigned int pool_size = 0;
unsigned int front_pad;
- pools = kzalloc(sizeof(*pools), GFP_KERNEL);
if (!pools)
return NULL;
- front_pad = roundup(per_bio_data_size, __alignof__(struct dm_target_io)) +
- offsetof(struct dm_target_io, clone);
+ type = filter_md_type(type, md);
- pools->io_pool = mempool_create_slab_pool(pool_size, _io_cache);
- if (!pools->io_pool)
- goto out;
+ switch (type) {
+ case DM_TYPE_BIO_BASED:
+ cachep = _io_cache;
+ pool_size = dm_get_reserved_bio_based_ios();
+ front_pad = roundup(per_bio_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone);
+ break;
+ case DM_TYPE_REQUEST_BASED:
+ cachep = _rq_tio_cache;
+ pool_size = dm_get_reserved_rq_based_ios();
+ pools->rq_pool = mempool_create_slab_pool(pool_size, _rq_cache);
+ if (!pools->rq_pool)
+ goto out;
+ /* fall through to setup remaining rq-based pools */
+ case DM_TYPE_MQ_REQUEST_BASED:
+ if (!pool_size)
+ pool_size = dm_get_reserved_rq_based_ios();
+ front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
+ /* per_bio_data_size is not used. See __bind_mempools(). */
+ WARN_ON(per_bio_data_size != 0);
+ break;
+ default:
+ BUG();
+ }
+
+ if (cachep) {
+ pools->io_pool = mempool_create_slab_pool(pool_size, cachep);
+ if (!pools->io_pool)
+ goto out;
+ }
pools->bs = bioset_create_nobvec(pool_size, front_pad);
if (!pools->bs)
goto out;
return pools;
-out:
- dm_free_md_mempools(pools);
- return NULL;
-}
-
-struct dm_md_mempools *dm_alloc_rq_mempools(struct mapped_device *md,
- unsigned type)
-{
- unsigned int pool_size = dm_get_reserved_rq_based_ios();
- struct dm_md_mempools *pools;
-
- pools = kzalloc(sizeof(*pools), GFP_KERNEL);
- if (!pools)
- return NULL;
- if (filter_md_type(type, md) == DM_TYPE_REQUEST_BASED) {
- pools->rq_pool = mempool_create_slab_pool(pool_size, _rq_cache);
- if (!pools->rq_pool)
- goto out;
- }
-
- pools->io_pool = mempool_create_slab_pool(pool_size, _rq_tio_cache);
- if (!pools->io_pool)
- goto out;
-
- return pools;
out:
dm_free_md_mempools(pools);
+
return NULL;
}
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