From 28e89fd914a22e8a64f05ae2f0048b06165f371b Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Thu, 7 Jun 2018 14:42:05 -0600
Subject: [PATCH] block: add bioset_init_from_src() helper
Add a helper that allows a caller to initialize a new bio_set,
using the settings from an existing bio_set.
Reported-by: Venkat R.B <vrbagal1@linux.vnet.ibm.com>
Tested-by: Venkat R.B <vrbagal1@linux.vnet.ibm.com>
Tested-by: Li Wang <liwang@redhat.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
block/bio.c | 18 ++++++++++++++++++
include/linux/bio.h | 1 +
2 files changed, 19 insertions(+)
diff --git a/block/bio.c b/block/bio.c
index 595663e0281a7..bf516d873ce9e 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1967,6 +1967,24 @@ int bioset_init(struct bio_set *bs,
}
EXPORT_SYMBOL(bioset_init);
+/*
+ * Initialize and setup a new bio_set, based on the settings from
+ * another bio_set.
+ */
+int bioset_init_from_src(struct bio_set *bs, struct bio_set *src)
+{
+ int flags;
+
+ flags = 0;
+ if (src->bvec_pool.min_nr)
+ flags |= BIOSET_NEED_BVECS;
+ if (src->rescue_workqueue)
+ flags |= BIOSET_NEED_RESCUER;
+
+ return bioset_init(bs, src->bio_pool.min_nr, src->front_pad, flags);
+}
+EXPORT_SYMBOL(bioset_init_from_src);
+
#ifdef CONFIG_BLK_CGROUP
/**
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 810a8bee8f859..84abd1706dcb8 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -417,6 +417,7 @@ enum {
extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags);
extern void bioset_exit(struct bio_set *);
extern int biovec_init_pool(mempool_t *pool, int pool_entries);
+extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src);
extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *);
extern void bio_put(struct bio *);
--
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