diff options
author | 2022-01-18 10:50:48 -0500 | |
---|---|---|
committer | 2022-03-21 12:59:02 -0400 | |
commit | 74e8ee4708a8edabbbc7ab8c12ec24d7a561bb41 (patch) | |
tree | df1e6dd0033ffc9450c680800458c8ed06f01d8f /include/linux/mm.h | |
parent | mm/vmscan: Turn page_check_dirty_writeback() into folio_check_dirty_writeback() (diff) | |
download | linux-74e8ee4708a8edabbbc7ab8c12ec24d7a561bb41.tar.gz linux-74e8ee4708a8edabbbc7ab8c12ec24d7a561bb41.tar.bz2 linux-74e8ee4708a8edabbbc7ab8c12ec24d7a561bb41.zip |
mm: Turn head_compound_mapcount() into folio_entire_mapcount()
Adjust documentation to be more clear.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'include/linux/mm.h')
-rw-r--r-- | include/linux/mm.h | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index dede2eda4d7f..70f0ca217962 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -776,21 +776,26 @@ static inline int is_vmalloc_or_module_addr(const void *x) } #endif -static inline int head_compound_mapcount(struct page *head) +/* + * How many times the entire folio is mapped as a single unit (eg by a + * PMD or PUD entry). This is probably not what you want, except for + * debugging purposes; look at folio_mapcount() or page_mapcount() + * instead. + */ +static inline int folio_entire_mapcount(struct folio *folio) { - return atomic_read(compound_mapcount_ptr(head)) + 1; + VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); + return atomic_read(folio_mapcount_ptr(folio)) + 1; } /* * Mapcount of compound page as a whole, does not include mapped sub-pages. * - * Must be called only for compound pages or any their tail sub-pages. + * Must be called only for compound pages. */ static inline int compound_mapcount(struct page *page) { - VM_BUG_ON_PAGE(!PageCompound(page), page); - page = compound_head(page); - return head_compound_mapcount(page); + return folio_entire_mapcount(page_folio(page)); } /* |