[PATCH v13 118/137] mm/filemap: Convert filemap_get_pages to use folios

Matthew Wilcox (Oracle)
2021-07-12T04:09:46Z

This saves a few calls to compound_head(), including one in
filemap_update_page(). Shrinks the kernel by 78 bytes.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
mm/filemap.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index b7fb0a4479ea..6700fbd9e8f6 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2355,9 +2355,8 @@ static bool filemap_range_uptodate(struct address_space *mapping,

static int filemap_update_page(struct kiocb *iocb,
struct address_space *mapping, struct iov_iter *iter,
- struct page *page)
+ struct folio *folio)
{
- struct folio *folio = page_folio(page);
int error;

if (!folio_trylock(folio)) {
@@ -2426,13 +2425,13 @@ static int filemap_create_folio(struct file *file,
}

static int filemap_readahead(struct kiocb *iocb, struct file *file,
- struct address_space *mapping, struct page *page,
+ struct address_space *mapping, struct folio *folio,
pgoff_t last_index)
{
if (iocb->ki_flags & IOCB_NOIO)
return -EAGAIN;
- page_cache_async_readahead(mapping, &file->f_ra, file, page,
- page->index, last_index - page->index);
+ page_cache_async_readahead(mapping, &file->f_ra, file, &folio->page,
+ folio->index, last_index - folio->index);
return 0;
}

@@ -2444,7 +2443,7 @@ static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter,
struct file_ra_state *ra = &filp->f_ra;
pgoff_t index = iocb->ki_pos >> PAGE_SHIFT;
pgoff_t last_index;
- struct page *page;
+ struct folio *folio;
int err = 0;

last_index = DIV_ROUND_UP(iocb->ki_pos + iter->count, PAGE_SIZE);
@@ -2470,16 +2469,16 @@ static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter,
return err;
}

- page = pvec->pages[pagevec_count(pvec) - 1];
- if (PageReadahead(page)) {
- err = filemap_readahead(iocb, filp, mapping, page, last_index);
+ folio = page_folio(pvec->pages[pagevec_count(pvec) - 1]);
+ if (folio_readahead(folio)) {
+ err = filemap_readahead(iocb, filp, mapping, folio, last_index);
if (err)
goto err;
}
- if (!PageUptodate(page)) {
+ if (!folio_uptodate(folio)) {
if ((iocb->ki_flags & IOCB_WAITQ) && pagevec_count(pvec) > 1)
iocb->ki_flags |= IOCB_NOWAIT;
- err = filemap_update_page(iocb, mapping, iter, page);
+ err = filemap_update_page(iocb, mapping, iter, folio);
if (err)
goto err;
}
@@ -2487,7 +2486,7 @@ static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter,
return 0;
err:
if (err < 0)
- put_page(page);
+ folio_put(folio);
if (likely(--pvec->nr))
return 0;
if (err == AOP_TRUNCATED_PAGE)
--
2.30.2