The patch titled Subject: mm: make page_ext_get() take a const argument has been added to the -mm mm-unstable branch. Its filename is mm-make-page_ext_get-take-a-const-argument.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-make-page_ext_get-take-a-const-argument.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: mm: make page_ext_get() take a const argument Date: Tue, 26 Mar 2024 17:10:25 +0000 In order to constify other functions, we need page_ext_get() to be const. This is no problem as lookup_page_ext() already takes a const argument. Link: https://lkml.kernel.org/r/20240326171045.410737-4-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/page_ext.h | 4 ++-- include/linux/pgalloc_tag.h | 2 -- mm/page_ext.c | 2 +- 3 files changed, 3 insertions(+), 5 deletions(-) --- a/include/linux/page_ext.h~mm-make-page_ext_get-take-a-const-argument +++ a/include/linux/page_ext.h @@ -77,7 +77,7 @@ static inline void page_ext_init(void) } #endif -extern struct page_ext *page_ext_get(struct page *page); +extern struct page_ext *page_ext_get(const struct page *page); extern void page_ext_put(struct page_ext *page_ext); static inline void *page_ext_data(struct page_ext *page_ext, @@ -117,7 +117,7 @@ static inline void page_ext_init_flatmem { } -static inline struct page_ext *page_ext_get(struct page *page) +static inline struct page_ext *page_ext_get(const struct page *page) { return NULL; } --- a/include/linux/pgalloc_tag.h~mm-make-page_ext_get-take-a-const-argument +++ a/include/linux/pgalloc_tag.h @@ -12,8 +12,6 @@ #include <linux/page_ext.h> extern struct page_ext_operations page_alloc_tagging_ops; -extern struct page_ext *page_ext_get(struct page *page); -extern void page_ext_put(struct page_ext *page_ext); static inline union codetag_ref *codetag_ref_from_page_ext(struct page_ext *page_ext) { --- a/mm/page_ext.c~mm-make-page_ext_get-take-a-const-argument +++ a/mm/page_ext.c @@ -514,7 +514,7 @@ void __meminit pgdat_page_ext_init(struc * Context: Any context. Caller may not sleep until they have called * page_ext_put(). */ -struct page_ext *page_ext_get(struct page *page) +struct page_ext *page_ext_get(const struct page *page) { struct page_ext *page_ext; _ Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are mm-always-initialise-folio-_deferred_list.patch mm-create-folio_flag_false-and-folio_type_ops-macros.patch mm-remove-folio_prep_large_rmappable.patch mm-support-page_mapcount-on-page_has_type-pages.patch mm-turn-folio_test_hugetlb-into-a-pagetype.patch mm-turn-folio_test_hugetlb-into-a-pagetype-fix.patch mm-remove-a-call-to-compound_head-from-is_page_hwpoison.patch mm-free-up-pg_slab.patch mm-free-up-pg_slab-fix.patch mm-improve-dumping-of-mapcount-and-page_type.patch hugetlb-remove-mention-of-destructors.patch sh-remove-use-of-pg_arch_1-on-individual-pages.patch xtensa-remove-uses-of-pg_arch_1-on-individual-pages.patch mm-make-page_ext_get-take-a-const-argument.patch mm-make-folio_test_idle-and-folio_test_young-take-a-const-argument.patch mm-make-is_free_buddy_page-take-a-const-argument.patch mm-make-page_mapped-take-a-const-argument.patch mm-convert-arch_clear_hugepage_flags-to-take-a-folio.patch slub-remove-use-of-page-flags.patch remove-references-to-page-flags-in-documentation.patch proc-rewrite-stable_page_flags.patch