diff options
| -rw-r--r-- | include/linux/rmap.h | 2 | ||||
| -rw-r--r-- | mm/rmap.c | 60 |
2 files changed, 48 insertions, 14 deletions
diff --git a/include/linux/rmap.h b/include/linux/rmap.h index b87d01660412..a3825ce81102 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -198,6 +198,8 @@ void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, unsigned long address); void page_add_file_rmap(struct page *, struct vm_area_struct *, bool compound); +void folio_add_file_rmap_range(struct folio *, struct page *, unsigned int nr, + struct vm_area_struct *, bool compound); void page_remove_rmap(struct page *, struct vm_area_struct *, bool compound); diff --git a/mm/rmap.c b/mm/rmap.c index 51ec8aa5e61f..1f04debdc87a 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1294,31 +1294,39 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, } /** - * page_add_file_rmap - add pte mapping to a file page - * @page: the page to add the mapping to + * folio_add_file_rmap_range - add pte mapping to page range of a folio + * @folio: The folio to add the mapping to + * @page: The first page to add + * @nr_pages: The number of pages which will be mapped * @vma: the vm area in which the mapping is added * @compound: charge the page as compound or small page * + * The page range of folio is defined by [first_page, first_page + nr_pages) + * * The caller needs to hold the pte lock. */ -void page_add_file_rmap(struct page *page, struct vm_area_struct *vma, - bool compound) +void folio_add_file_rmap_range(struct folio *folio, struct page *page, + unsigned int nr_pages, struct vm_area_struct *vma, + bool compound) { - struct folio *folio = page_folio(page); atomic_t *mapped = &folio->_nr_pages_mapped; - int nr = 0, nr_pmdmapped = 0; - bool first; + unsigned int nr_pmdmapped = 0, first; + int nr = 0; - VM_BUG_ON_PAGE(compound && !PageTransHuge(page), page); + VM_WARN_ON_FOLIO(compound && !folio_test_pmd_mappable(folio), folio); /* Is page being mapped by PTE? Is this its first map to be added? */ if (likely(!compound)) { - first = atomic_inc_and_test(&page->_mapcount); - nr = first; - if (first && folio_test_large(folio)) { - nr = atomic_inc_return_relaxed(mapped); - nr = (nr < COMPOUND_MAPPED); - } + do { + first = atomic_inc_and_test(&page->_mapcount); + if (first && folio_test_large(folio)) { + first = atomic_inc_return_relaxed(mapped); + first = (first < COMPOUND_MAPPED); + } + + if (first) + nr++; + } while (page++, --nr_pages > 0); } else if (folio_test_pmd_mappable(folio)) { /* That test is redundant: it's for safety or to optimize out */ @@ -1348,6 +1356,30 @@ void page_add_file_rmap(struct page *page, struct vm_area_struct *vma, } /** + * page_add_file_rmap - add pte mapping to a file page + * @page: the page to add the mapping to + * @vma: the vm area in which the mapping is added + * @compound: charge the page as compound or small page + * + * The caller needs to hold the pte lock. + */ +void page_add_file_rmap(struct page *page, struct vm_area_struct *vma, + bool compound) +{ + struct folio *folio = page_folio(page); + unsigned int nr_pages; + + VM_WARN_ON_ONCE_PAGE(compound && !PageTransHuge(page), page); + + if (likely(!compound)) + nr_pages = 1; + else + nr_pages = folio_nr_pages(folio); + + folio_add_file_rmap_range(folio, page, nr_pages, vma, compound); +} + +/** * page_remove_rmap - take down pte mapping from a page * @page: page to remove mapping from * @vma: the vm area from which the mapping is removed |