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().
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
---
mm/memory.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index d63f0d5abcc9..3dd6c57e6511 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;
--
2.50.0
On 09.07.25 21:40, Vishal Moola (Oracle) wrote:
> 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().
>
> Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
> ---
> mm/memory.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index d63f0d5abcc9..3dd6c57e6511 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);
Acked-by: David Hildenbrand <david@redhat.com>
--
Cheers,
David / dhildenb
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