The patch titled
Subject: mm: remove page_maybe_dma_pinned()
has been added to the -mm mm-unstable branch. Its filename is
mm-remove-page_maybe_dma_pinned.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-remove-page_maybe_dma_pinned.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: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Subject: mm: remove page_maybe_dma_pinned()
Date: Tue, 4 Jun 2024 19:48:20 +0800
After the last user of page_maybe_dma_pinned() is converted to
folio_maybe_dma_pinned(), remove page_maybe_dma_pinned() and update the
document and comment.
Link: https://lkml.kernel.org/r/20240604114822.2089819-3-wangkefeng.wang@xxxxxxxxxx
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Helge Deller <deller@xxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/core-api/pin_user_pages.rst | 10 +++++-----
include/linux/mm.h | 9 ++-------
2 files changed, 7 insertions(+), 12 deletions(-)
--- a/Documentation/core-api/pin_user_pages.rst~mm-remove-page_maybe_dma_pinned
+++ a/Documentation/core-api/pin_user_pages.rst
@@ -196,20 +196,20 @@ INCORRECT (uses FOLL_GET calls):
write to the data within the pages
put_page()
-page_maybe_dma_pinned(): the whole point of pinning
+folio_maybe_dma_pinned(): the whole point of pinning
===================================================
-The whole point of marking pages as "DMA-pinned" or "gup-pinned" is to be able
-to query, "is this page DMA-pinned?" That allows code such as page_mkclean()
+The whole point of marking folios as "DMA-pinned" or "gup-pinned" is to be able
+to query, "is this folio DMA-pinned?" That allows code such as page_mkclean()
(and file system writeback code in general) to make informed decisions about
-what to do when a page cannot be unmapped due to such pins.
+what to do when a folio cannot be unmapped due to such pins.
What to do in those cases is the subject of a years-long series of discussions
and debates (see the References at the end of this document). It's a TODO item
here: fill in the details once that's worked out. Meanwhile, it's safe to say
that having this available: ::
- static inline bool page_maybe_dma_pinned(struct page *page)
+ static inline bool folio_maybe_dma_pinned(struct folio *folio)
...is a prerequisite to solving the long-running gup+DMA problem.
--- a/include/linux/mm.h~mm-remove-page_maybe_dma_pinned
+++ a/include/linux/mm.h
@@ -1940,8 +1940,8 @@ static inline struct folio *pfn_folio(un
*
* For more information, please see Documentation/core-api/pin_user_pages.rst.
*
- * Return: True, if it is likely that the page has been "dma-pinned".
- * False, if the page is definitely not dma-pinned.
+ * Return: True, if it is likely that the folio has been "dma-pinned".
+ * False, if the folio is definitely not dma-pinned.
*/
static inline bool folio_maybe_dma_pinned(struct folio *folio)
{
@@ -1960,11 +1960,6 @@ static inline bool folio_maybe_dma_pinne
GUP_PIN_COUNTING_BIAS;
}
-static inline bool page_maybe_dma_pinned(struct page *page)
-{
- return folio_maybe_dma_pinned(page_folio(page));
-}
-
/*
* This should most likely only be called during fork() to see whether we
* should break the cow immediately for an anon page on the src mm.
_
Patches currently in -mm which might be from wangkefeng.wang@xxxxxxxxxx are
mm-add-folio_alloc_mpol.patch
mm-mempolicy-use-folio_alloc_mpol_noprof-in-vma_alloc_folio_noprof.patch
mm-mempolicy-use-folio_alloc_mpol-in-alloc_migration_target_by_mpol.patch
mm-shmem-use-folio_alloc_mpol-in-shmem_alloc_folio.patch
mm-refactor-folio_undo_large_rmappable.patch
mm-memcontrol-remove-page_memcg.patch
rmap-remove-define_page_vma_walk.patch
mm-migrate-simplify-__buffer_migrate_folio.patch
mm-migrate_device-use-a-newfolio-in-__migrate_device_pages.patch
mm-migrate_device-unify-migrate-folio-for-migrate_sync_no_copy.patch
mm-migrate-remove-migrate_folio_extra.patch
mm-remove-migrate_sync_no_copy-mode.patch
fs-proc-task_mmu-use-folio-api-in-pte_is_pinned.patch
mm-remove-page_maybe_dma_pinned.patch
fb_defio-use-a-folio-in-fb_deferred_io_work.patch
mm-remove-page_mkclean.patch
