+ s390-mm-use-pmd_pgtable_page-helper-in-__gmap_segment_gaddr.patch added to mm-unstable branch

+ s390-mm-use-pmd_pgtable_page-helper-in-__gmap_segment_gaddr.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: s390/mm: use pmd_pgtable_page() helper in __gmap_segment_gaddr()
has been added to the -mm mm-unstable branch.  Its filename is
     s390-mm-use-pmd_pgtable_page-helper-in-__gmap_segment_gaddr.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/s390-mm-use-pmd_pgtable_page-helper-in-__gmap_segment_gaddr.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Anshuman Khandual <anshuman.khandual@arm.com>
Subject: s390/mm: use pmd_pgtable_page() helper in __gmap_segment_gaddr()
Date: Fri, 25 Nov 2022 09:15:02 +0530

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.

Link: https://lkml.kernel.org/r/20221125034502.1559986-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/s390/mm/gmap.c |    5 ++---
 include/linux/mm.h  |    2 +-
 2 files changed, 3 insertions(+), 4 deletions(-)

--- a/arch/s390/mm/gmap.c~s390-mm-use-pmd_pgtable_page-helper-in-__gmap_segment_gaddr
+++ a/arch/s390/mm/gmap.c
@@ -336,12 +336,11 @@ static int gmap_alloc_table(struct gmap
 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;
 }
 
--- a/include/linux/mm.h~s390-mm-use-pmd_pgtable_page-helper-in-__gmap_segment_gaddr
+++ a/include/linux/mm.h
@@ -2480,7 +2480,7 @@ static inline void pgtable_pte_page_dtor
 
 #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));
_

Patches currently in -mm which might be from anshuman.khandual@arm.com are

documentation-mm-update-pmd_present-in-arch_pgtable_helpersrst.patch
mm-thp-rename-pmd_to_page-as-pmd_pgtable_page.patch
s390-mm-use-pmd_pgtable_page-helper-in-__gmap_segment_gaddr.patch