[PATCH v14 052/138] mm: Add folio_raw_mapping()
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Date: 2021-07-15 04:19:49
Also in:
linux-fsdevel, lkml
Subsystem:
memory management, memory management - core, the rest · Maintainers:
Andrew Morton, David Hildenbrand, Linus Torvalds
Convert __page_rmapping to folio_raw_mapping and move it to mm/internal.h. It's only a couple of instructions (load and mask), so it's definitely going to be cheaper to inline it than call it. Leave page_rmapping out of line. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- mm/internal.h | 7 +++++++ mm/util.c | 20 ++++---------------- 2 files changed, 11 insertions(+), 16 deletions(-)
diff --git a/mm/internal.h b/mm/internal.h
index 1a8851b73031..fa31a7f0ed79 100644
--- a/mm/internal.h
+++ b/mm/internal.h@@ -34,6 +34,13 @@ void page_writeback_init(void); +static inline void *folio_raw_mapping(struct folio *folio) +{ + unsigned long mapping = (unsigned long)folio->mapping; + + return (void *)(mapping & ~PAGE_MAPPING_FLAGS); +} + vm_fault_t do_swap_page(struct vm_fault *vmf); void folio_rotate_reclaimable(struct folio *folio);
diff --git a/mm/util.c b/mm/util.c
index e8c12350b3eb..d0aa1d9c811e 100644
--- a/mm/util.c
+++ b/mm/util.c@@ -635,21 +635,10 @@ void kvfree_sensitive(const void *addr, size_t len) } EXPORT_SYMBOL(kvfree_sensitive); -static inline void *__page_rmapping(struct page *page) -{ - unsigned long mapping; - - mapping = (unsigned long)page->mapping; - mapping &= ~PAGE_MAPPING_FLAGS; - - return (void *)mapping; -} - /* Neutral page->mapping pointer to address_space or anon_vma or other */ void *page_rmapping(struct page *page) { - page = compound_head(page); - return __page_rmapping(page); + return folio_raw_mapping(page_folio(page)); } /**
@@ -680,13 +669,12 @@ EXPORT_SYMBOL(folio_mapped); struct anon_vma *page_anon_vma(struct page *page) { - unsigned long mapping; + struct folio *folio = page_folio(page); + unsigned long mapping = (unsigned long)folio->mapping; - page = compound_head(page); - mapping = (unsigned long)page->mapping; if ((mapping & PAGE_MAPPING_FLAGS) != PAGE_MAPPING_ANON) return NULL; - return __page_rmapping(page); + return (void *)(mapping - PAGE_MAPPING_ANON); } /**
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2.30.2