From 0c092fef53f08f1e461b180c61dddc30491ec855 Mon Sep 17 00:00:00 2001 From: "Vishal Moola (Oracle)" Date: Wed, 9 Jul 2025 12:40:17 -0700 Subject: [PATCH] mm/memory.c: use folios in __access_remote_vm() 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) Acked-by: David Hildenbrand Cc: Jordan Rome Cc: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- mm/memory.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index cb2f1296854a6..bc27b1990fcba 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -6691,6 +6691,7 @@ static int __access_remote_vm(struct mm_struct *mm, unsigned long addr, 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_struct *mm, unsigned long addr, 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; -- 2.47.2