On Fri, Nov 25, 2022 at 09:15:02AM +0530, Anshuman Khandual wrote: Hi Anshuman, > In __gmap_segment_gaddr() pmd level page table page is being extracted from > the pmd pointer, similar to pmd_pgtable_page() implementation. This reduces > some redundancy by directly using pmd_pgtable_page() instead, though first > making it available. [...] > diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c > index 02d15c8dc92e..8947451ae021 100644 > --- a/arch/s390/mm/gmap.c > +++ b/arch/s390/mm/gmap.c > @@ -336,12 +336,11 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table, > static unsigned long __gmap_segment_gaddr(unsigned long *entry) > { > struct page *page; > - unsigned long offset, mask; > + unsigned long offset; > > offset = (unsigned long) entry / sizeof(unsigned long); > offset = (offset & (PTRS_PER_PMD - 1)) * PMD_SIZE; > - mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); > - page = virt_to_page((void *)((unsigned long) entry & mask)); > + page = pmd_pgtable_page((pmd_t *) entry); > return page->index + offset; > } Looks okay to me. > diff --git a/include/linux/mm.h b/include/linux/mm.h > index e9e387caffac..5ead9e997510 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -2403,7 +2403,7 @@ static inline void pgtable_pte_page_dtor(struct page *page) > > #if USE_SPLIT_PMD_PTLOCKS > > -static struct page *pmd_pgtable_page(pmd_t *pmd) > +static inline struct page *pmd_pgtable_page(pmd_t *pmd) > { > unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); > return virt_to_page((void *)((unsigned long) pmd & mask)); This chunk does not appear to belong to this patch. Thanks!