From 79e178f4383a3a645f76bc2dd44c477b361c6a98 Mon Sep 17 00:00:00 2001 From: Zhou Wang Date: Wed, 24 Jul 2019 11:54:23 +0800 Subject: [PATCH] lib: scatterlist: Fix to support no mapped sg In function sg_split, the second sg_calculate_split will return -EINVAL when in_mapped_nents is 0. Indeed there is no need to do second sg_calculate_split and sg_split_mapped when in_mapped_nents is 0, as in_mapped_nents indicates no mapped entry in original sgl. Signed-off-by: Zhou Wang Acked-by: Robert Jarzmik Signed-off-by: Jens Axboe --- lib/sg_split.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/lib/sg_split.c b/lib/sg_split.c index 9982c63d1063..60a0babebf2e 100644 --- a/lib/sg_split.c +++ b/lib/sg_split.c @@ -176,11 +176,13 @@ int sg_split(struct scatterlist *in, const int in_mapped_nents, * The order of these 3 calls is important and should be kept. */ sg_split_phys(splitters, nb_splits); - ret = sg_calculate_split(in, in_mapped_nents, nb_splits, skip, - split_sizes, splitters, true); - if (ret < 0) - goto err; - sg_split_mapped(splitters, nb_splits); + if (in_mapped_nents) { + ret = sg_calculate_split(in, in_mapped_nents, nb_splits, skip, + split_sizes, splitters, true); + if (ret < 0) + goto err; + sg_split_mapped(splitters, nb_splits); + } for (i = 0; i < nb_splits; i++) { out[i] = splitters[i].out_sg;