| Message ID | 20230327211548.462509-3-jiaqiyan@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Memory poison recovery in khugepaged collapsing | expand |
On Mon, Mar 27, 2023 at 2:15 PM Jiaqi Yan <jiaqiyan@google.com> wrote: > > Similar to how copy_mc_user_highpage is implemented for > copy_user_highpage on #MC supported architecture, introduce > the #MC handled version of copy_highpage. > > This helper has immediate usage when khugepaged wants to copy > file-backed memory pages and tolerate #MC. > > Signed-off-by: Jiaqi Yan <jiaqiyan@google.com> Reviewed-by: Yang Shi <shy828301@gmail.com> BTW, you could preserve the reviewed/acked tags as long as there is no significant change between two versions. > --- > include/linux/highmem.h | 54 +++++++++++++++++++++++++++++++---------- > 1 file changed, 41 insertions(+), 13 deletions(-) > > diff --git a/include/linux/highmem.h b/include/linux/highmem.h > index 9c7cdaa3de8cd..4de1dbcd3ef64 100644 > --- a/include/linux/highmem.h > +++ b/include/linux/highmem.h > @@ -315,7 +315,29 @@ static inline void copy_user_highpage(struct page *to, struct page *from, > > #endif > > +#ifndef __HAVE_ARCH_COPY_HIGHPAGE > + > +static inline void copy_highpage(struct page *to, struct page *from) > +{ > + char *vfrom, *vto; > + > + vfrom = kmap_local_page(from); > + vto = kmap_local_page(to); > + copy_page(vto, vfrom); > + kmsan_copy_page_meta(to, from); > + kunmap_local(vto); > + kunmap_local(vfrom); > +} > + > +#endif > + > #ifdef copy_mc_to_kernel > +/* > + * If architecture supports machine check exception handling, define the > + * #MC versions of copy_user_highpage and copy_highpage. They copy a memory > + * page with #MC in source page (@from) handled, and return the number > + * of bytes not copied if there was a #MC, otherwise 0 for success. > + */ > static inline int copy_mc_user_highpage(struct page *to, struct page *from, > unsigned long vaddr, struct vm_area_struct *vma) > { > @@ -332,29 +354,35 @@ static inline int copy_mc_user_highpage(struct page *to, struct page *from, > > return ret; > } > -#else > -static inline int copy_mc_user_highpage(struct page *to, struct page *from, > - unsigned long vaddr, struct vm_area_struct *vma) > -{ > - copy_user_highpage(to, from, vaddr, vma); > - return 0; > -} > -#endif > > -#ifndef __HAVE_ARCH_COPY_HIGHPAGE > - > -static inline void copy_highpage(struct page *to, struct page *from) > +static inline int copy_mc_highpage(struct page *to, struct page *from) > { > + unsigned long ret; > char *vfrom, *vto; > > vfrom = kmap_local_page(from); > vto = kmap_local_page(to); > - copy_page(vto, vfrom); > - kmsan_copy_page_meta(to, from); > + ret = copy_mc_to_kernel(vto, vfrom, PAGE_SIZE); > + if (!ret) > + kmsan_copy_page_meta(to, from); > kunmap_local(vto); > kunmap_local(vfrom); > + > + return ret; > +} > +#else > +static inline int copy_mc_user_highpage(struct page *to, struct page *from, > + unsigned long vaddr, struct vm_area_struct *vma) > +{ > + copy_user_highpage(to, from, vaddr, vma); > + return 0; > } > > +static inline int copy_mc_highpage(struct page *to, struct page *from) > +{ > + copy_highpage(to, from); > + return 0; > +} > #endif > > static inline void memcpy_page(struct page *dst_page, size_t dst_off, > -- > 2.40.0.348.gf938b09366-goog >
diff --git a/include/linux/highmem.h b/include/linux/highmem.h index 9c7cdaa3de8cd..4de1dbcd3ef64 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -315,7 +315,29 @@ static inline void copy_user_highpage(struct page *to, struct page *from, #endif +#ifndef __HAVE_ARCH_COPY_HIGHPAGE + +static inline void copy_highpage(struct page *to, struct page *from) +{ + char *vfrom, *vto; + + vfrom = kmap_local_page(from); + vto = kmap_local_page(to); + copy_page(vto, vfrom); + kmsan_copy_page_meta(to, from); + kunmap_local(vto); + kunmap_local(vfrom); +} + +#endif + #ifdef copy_mc_to_kernel +/* + * If architecture supports machine check exception handling, define the + * #MC versions of copy_user_highpage and copy_highpage. They copy a memory + * page with #MC in source page (@from) handled, and return the number + * of bytes not copied if there was a #MC, otherwise 0 for success. + */ static inline int copy_mc_user_highpage(struct page *to, struct page *from, unsigned long vaddr, struct vm_area_struct *vma) { @@ -332,29 +354,35 @@ static inline int copy_mc_user_highpage(struct page *to, struct page *from, return ret; } -#else -static inline int copy_mc_user_highpage(struct page *to, struct page *from, - unsigned long vaddr, struct vm_area_struct *vma) -{ - copy_user_highpage(to, from, vaddr, vma); - return 0; -} -#endif -#ifndef __HAVE_ARCH_COPY_HIGHPAGE - -static inline void copy_highpage(struct page *to, struct page *from) +static inline int copy_mc_highpage(struct page *to, struct page *from) { + unsigned long ret; char *vfrom, *vto; vfrom = kmap_local_page(from); vto = kmap_local_page(to); - copy_page(vto, vfrom); - kmsan_copy_page_meta(to, from); + ret = copy_mc_to_kernel(vto, vfrom, PAGE_SIZE); + if (!ret) + kmsan_copy_page_meta(to, from); kunmap_local(vto); kunmap_local(vfrom); + + return ret; +} +#else +static inline int copy_mc_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma) +{ + copy_user_highpage(to, from, vaddr, vma); + return 0; } +static inline int copy_mc_highpage(struct page *to, struct page *from) +{ + copy_highpage(to, from); + return 0; +} #endif static inline void memcpy_page(struct page *dst_page, size_t dst_off,
Similar to how copy_mc_user_highpage is implemented for copy_user_highpage on #MC supported architecture, introduce the #MC handled version of copy_highpage. This helper has immediate usage when khugepaged wants to copy file-backed memory pages and tolerate #MC. Signed-off-by: Jiaqi Yan <jiaqiyan@google.com> --- include/linux/highmem.h | 54 +++++++++++++++++++++++++++++++---------- 1 file changed, 41 insertions(+), 13 deletions(-)