+ mm-memoryc-use-folios-in-__access_remote_vm.patch added to mm-new branch

+ mm-memoryc-use-folios-in-__access_remote_vm.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: mm/memory.c: use folios in __access_remote_vm()
has been added to the -mm mm-new branch.  Its filename is
     mm-memoryc-use-folios-in-__access_remote_vm.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memoryc-use-folios-in-__access_remote_vm.patch

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

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
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------------------------------------------------------
From: "Vishal Moola (Oracle)" <vishal.moola@gmail.com>
Subject: mm/memory.c: use folios in __access_remote_vm()
Date: Wed, 9 Jul 2025 12:40:17 -0700

Use kmap_local_folio() instead of kmap_local_page().  Replaces 2 calls to
compound_head() with one.

This prepares us for the removal of unmap_and_put_page().

Link: https://lkml.kernel.org/r/20250709194017.927978-5-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jordan Rome <linux@jordanrome.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

--- a/mm/memory.c~mm-memoryc-use-folios-in-__access_remote_vm
+++ a/mm/memory.c
@@ -6691,6 +6691,7 @@ static int __access_remote_vm(struct mm_
 	while (len) {
 		int bytes, offset;
 		void *maddr;
+		struct folio *folio;
 		struct vm_area_struct *vma = NULL;
 		struct page *page = get_user_page_vma_remote(mm, addr,
 							     gup_flags, &vma);
@@ -6722,21 +6723,22 @@ static int __access_remote_vm(struct mm_
 			if (bytes <= 0)
 				break;
 		} else {
+			folio = page_folio(page);
 			bytes = len;
 			offset = addr & (PAGE_SIZE-1);
 			if (bytes > PAGE_SIZE-offset)
 				bytes = PAGE_SIZE-offset;
 
-			maddr = kmap_local_page(page);
+			maddr = kmap_local_folio(folio, folio_page_idx(folio, page) * PAGE_SIZE);
 			if (write) {
 				copy_to_user_page(vma, page, addr,
 						  maddr + offset, buf, bytes);
-				set_page_dirty_lock(page);
+				folio_mark_dirty_lock(folio);
 			} else {
 				copy_from_user_page(vma, page, addr,
 						    buf, maddr + offset, bytes);
 			}
-			unmap_and_put_page(page, maddr);
+			folio_release_kmap(folio, maddr);
 		}
 		len -= bytes;
 		buf += bytes;
_

Patches currently in -mm which might be from vishal.moola@gmail.com are

mm-memoryc-use-folios-in-__copy_remote_vm_str.patch
mm-memoryc-use-folios-in-__access_remote_vm.patch
mm-remove-unmap_and_put_page.patch