mm: remove page_maybe_dma_pinned()
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.
[wangkefeng.wang@huawei.com: fix pin_user_pages.rst underlining]
Link: https://lkml.kernel.org/r/61b256c7-4989-44ec-83db-f34a1bd4be2d@huawei.com
Link: https://lkml.kernel.org/r/20240604114822.2089819-3-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Helge Deller <deller@gmx.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff --git a/Documentation/core-api/pin_user_pages.rst b/Documentation/core-api/pin_user_pages.rst
index 6b5f7e6..57b1797 100644
--- a/Documentation/core-api/pin_user_pages.rst
+++ b/Documentation/core-api/pin_user_pages.rst
@@ -196,20 +196,20 @@
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.