> On 2021/01/27 9:36, Changheun Lee wrote: > >>> + > >>> /** > >>> * bio_reset - reinitialize a bio > >>> * @bio: bio to reset > >>> @@ -877,7 +892,7 @@ bool __bio_try_merge_page(struct bio *bio, struct > >>> page *page, > >>> struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; > >>> > >>> if (page_is_mergeable(bv, page, len, off, same_page)) { > >>> - if (bio->bi_iter.bi_size > UINT_MAX - len) { > >>> + if (bio->bi_iter.bi_size > bio_max_size(bio) - len) { > >>> *same_page = false; > >>> return false; > >>> } > >>> diff --git a/include/linux/bio.h b/include/linux/bio.h > >>> index 1edda614f7ce..cdb134ca7bf5 100644 > >>> --- a/include/linux/bio.h > >>> +++ b/include/linux/bio.h > >>> @@ -100,6 +100,8 @@ static inline void *bio_data(struct bio *bio) > >>> return NULL; > >>> } > >>> > >>> +extern unsigned int bio_max_size(struct bio *); > >> > >> No need for extern. > > > > It's just for compile warning in my test environment. > > I'll remove it too. But I think compile warning could be in the other > > .c file which includes bio.h. Is it OK? > > Hmmm... not having extern should not generate a compilation warning. There are > tons of functions declared without extern in header files in the kernel. What > compiler are you using ? >
Compiler imformation is below. CROSS_COMPILE: android/prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/bin/aarch64-linux-android- CC: android/prebuilts/clang/host/linux-x86/clang-r383902/bin/clang CLANG_TRIPLE: android/prebuilts/clang/host/linux-x86/clang-r383902/bin/aarch64-linux-gnu- CROSS_COMPILE_COMPAT: android/prebuilts/gcc/linux-x86/arm/arm-linux-androideabi-4.9/bin/arm-linux-androideabi- > > -- > Damien Le Moal > Western Digital Research > --- Changheun Lee Samsung Electronics