[dm-devel] [PATCH]md:dm.c Fix warning: statement with no effect

[Justin P. Mattock]

haven't heard any feedback on this any ideas?

> Ive noticed that having CONFIG_BLK_DEV_INTEGRITY=n I get warning messages generated by GCC(below)
>    CC      drivers/md/dm.o
> drivers/md/dm.c: In function 'split_bvec':
> drivers/md/dm.c:1117:3: warning: statement with no effect
> drivers/md/dm.c: In function 'clone_bio':
> drivers/md/dm.c:1145:3: warning: statement with no effect
>
> adding in some #ifdef's fixes this warning if someone chooses not to have
> CONFIG_BLK_DEV_INTEGRITY turned on. but keep in mind not sure if this is the best approach
> i.e. should something be done in bio.h?
> Also this patch fixes a comment which was hard to read at first. Anyways have a look
> when you have time, and let me know.
>
> Signed-off-by: Justin P. Mattock<justinmattock at gmail.com>
>
> ---
>   drivers/md/dm.c |    6 +++++-
>   1 files changed, 5 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/md/dm.c b/drivers/md/dm.c
> index d21e128..7c1cb04 100644
> --- a/drivers/md/dm.c
> +++ b/drivers/md/dm.c
> @@ -1091,7 +1091,7 @@ static void dm_bio_destructor(struct bio *bio)
>   }
>
>   /*
> - * Creates a little bio that is just does part of a bvec.
> + * Create a little bio that just does part of a bvec.
>    */
>   static struct bio *split_bvec(struct bio *bio, sector_t sector,
>   			      unsigned short idx, unsigned int offset,
> @@ -1114,7 +1114,9 @@ static struct bio *split_bvec(struct bio *bio, sector_t sector,
>   	clone->bi_flags |= 1<<  BIO_CLONED;
>
>   	if (bio_integrity(bio)) {
> +#ifdef CONFIG_BLK_DEV_INTEGRITY
>   		bio_integrity_clone(clone, bio, GFP_NOIO, bs);
> +#endif
>   		bio_integrity_trim(clone,
>   				   bio_sector_offset(bio, idx, offset), len);
>   	}
> @@ -1142,7 +1144,9 @@ static struct bio *clone_bio(struct bio *bio, sector_t sector,
>   	clone->bi_flags&= ~(1<<  BIO_SEG_VALID);
>
>   	if (bio_integrity(bio)) {
> +#ifdef CONFIG_BLK_DEV_INTEGRITY
>   		bio_integrity_clone(clone, bio, GFP_NOIO, bs);
> +#endif
>
>   		if (idx != bio->bi_idx || clone->bi_size<  bio->bi_size)
>   			bio_integrity_trim(clone,