[PATCH v14 123/138] mm/filemap: Use a folio in filemap_map_pages
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Date: 2021-07-15 05:17:53
Also in:
linux-fsdevel, lkml
Subsystem:
memory management, page cache, the rest · Maintainers:
Andrew Morton, Matthew Wilcox, Linus Torvalds
Saves 61 bytes due to fewer calls to compound_head(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- mm/filemap.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index 545323a77c1c..1c0c2663c57d 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c@@ -3105,7 +3105,7 @@ static bool filemap_map_pmd(struct vm_fault *vmf, struct page *page) return false; } -static struct page *next_uptodate_page(struct folio *folio, +static struct folio *next_uptodate_page(struct folio *folio, struct address_space *mapping, struct xa_state *xas, pgoff_t end_pgoff) {
@@ -3136,7 +3136,7 @@ static struct page *next_uptodate_page(struct folio *folio, max_idx = DIV_ROUND_UP(i_size_read(mapping->host), PAGE_SIZE); if (xas->xa_index >= max_idx) goto unlock; - return &folio->page; + return folio; unlock: folio_unlock(folio); skip:
@@ -3146,7 +3146,7 @@ static struct page *next_uptodate_page(struct folio *folio, return NULL; } -static inline struct page *first_map_page(struct address_space *mapping, +static inline struct folio *first_map_page(struct address_space *mapping, struct xa_state *xas, pgoff_t end_pgoff) {
@@ -3154,7 +3154,7 @@ static inline struct page *first_map_page(struct address_space *mapping, mapping, xas, end_pgoff); } -static inline struct page *next_map_page(struct address_space *mapping, +static inline struct folio *next_map_page(struct address_space *mapping, struct xa_state *xas, pgoff_t end_pgoff) {
@@ -3171,16 +3171,17 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf, pgoff_t last_pgoff = start_pgoff; unsigned long addr; XA_STATE(xas, &mapping->i_pages, start_pgoff); - struct page *head, *page; + struct folio *folio; + struct page *page; unsigned int mmap_miss = READ_ONCE(file->f_ra.mmap_miss); vm_fault_t ret = 0; rcu_read_lock(); - head = first_map_page(mapping, &xas, end_pgoff); - if (!head) + folio = first_map_page(mapping, &xas, end_pgoff); + if (!folio) goto out; - if (filemap_map_pmd(vmf, head)) { + if (filemap_map_pmd(vmf, &folio->page)) { ret = VM_FAULT_NOPAGE; goto out; }
@@ -3188,7 +3189,7 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf, addr = vma->vm_start + ((start_pgoff - vma->vm_pgoff) << PAGE_SHIFT); vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, addr, &vmf->ptl); do { - page = find_subpage(head, xas.xa_index); + page = folio_file_page(folio, xas.xa_index); if (PageHWPoison(page)) goto unlock;
@@ -3209,12 +3210,12 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf, do_set_pte(vmf, page, addr); /* no need to invalidate: a not-present page won't be cached */ update_mmu_cache(vma, addr, vmf->pte); - unlock_page(head); + folio_unlock(folio); continue; unlock: - unlock_page(head); - put_page(head); - } while ((head = next_map_page(mapping, &xas, end_pgoff)) != NULL); + folio_unlock(folio); + folio_put(folio); + } while ((folio = next_map_page(mapping, &xas, end_pgoff)) != NULL); pte_unmap_unlock(vmf->pte, vmf->ptl); out: rcu_read_unlock();
--
2.30.2