+ mm-export-pageheadhuge.patch added to -mm tree

+ mm-export-pageheadhuge.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: mm/hugetlb.c: export PageHeadHuge()
has been added to the -mm tree.  Its filename is
     mm-export-pageheadhuge.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-export-pageheadhuge.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-export-pageheadhuge.patch

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------------------------------------------------------
From: David Howells <dhowells@redhat.com>
Subject: mm/hugetlb.c: export PageHeadHuge()

Export PageHeadHuge() - it's used by folio_test_hugetlb() and thence by
such as folio_file_page() and folio_contains().  Matthew suggested I use
the first of those instead of doing the same calculation manually - but I
can't call it from a module.

Kirill suggested rearranging things to put it in a header, but that
introduces header dependencies because of where constants are defined.

Link: https://lkml.kernel.org/r/2494562.1646054576@warthog.procyon.org.uk
Link: https://lore.kernel.org/r/163707085314.3221130.14783857863702203440.stgit@warthog.procyon.org.uk/
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/hugetlb.c |    1 +
 1 file changed, 1 insertion(+)

--- a/mm/hugetlb.c~mm-export-pageheadhuge
+++ a/mm/hugetlb.c
@@ -1855,6 +1855,7 @@ int PageHeadHuge(struct page *page_head)
 
 	return page_head[1].compound_dtor == HUGETLB_PAGE_DTOR;
 }
+EXPORT_SYMBOL(PageHeadHuge);
 
 /*
  * Find and lock address space (mapping) in write mode.
_

Patches currently in -mm which might be from dhowells@redhat.com are

mm-export-pageheadhuge.patch
mutex-subsystem-synchro-test-module.patch