[PATCH 04/21] iomap: Convert to_iomap_page to take a folio

Matthew Wilcox (Oracle)
2021-11-01T20:49:27Z

The big comment about only using a head page can go away now that
it takes a folio argument.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
---
fs/iomap/buffered-io.c | 32 +++++++++++++++-----------------
1 file changed, 15 insertions(+), 17 deletions(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 9cc5798423d1..24a2aa69c467 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -22,8 +22,8 @@
#include "../internal.h"

/*
- * Structure allocated for each page or THP when block size < page size
- * to track sub-page uptodate status and I/O completions.
+ * Structure allocated for each folio when block size < folio size
+ * to track sub-folio uptodate status and I/O completions.
*/
struct iomap_page {
atomic_t read_bytes_pending;
@@ -32,17 +32,10 @@ struct iomap_page {
unsigned long uptodate[];
};

-static inline struct iomap_page *to_iomap_page(struct page *page)
+static inline struct iomap_page *to_iomap_page(struct folio *folio)
{
- /*
- * per-block data is stored in the head page. Callers should
- * not be dealing with tail pages, and if they are, they can
- * call thp_head() first.
- */
- VM_BUG_ON_PGFLAGS(PageTail(page), page);
-
- if (page_has_private(page))
- return (struct iomap_page *)page_private(page);
+ if (folio_test_private(folio))
+ return folio_get_private(folio);
return NULL;
}

@@ -51,7 +44,8 @@ static struct bio_set iomap_ioend_bioset;
static struct iomap_page *
iomap_page_create(struct inode *inode, struct page *page)
{
- struct iomap_page *iop = to_iomap_page(page);
+ struct folio *folio = page_folio(page);
+ struct iomap_page *iop = to_iomap_page(folio);
unsigned int nr_blocks = i_blocks_per_page(inode, page);

if (iop || nr_blocks <= 1)
@@ -144,7 +138,8 @@ iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop,
static void
iomap_iop_set_range_uptodate(struct page *page, unsigned off, unsigned len)
{
- struct iomap_page *iop = to_iomap_page(page);
+ struct folio *folio = page_folio(page);
+ struct iomap_page *iop = to_iomap_page(folio);
struct inode *inode = page->mapping->host;
unsigned first = off >> inode->i_blkbits;
unsigned last = (off + len - 1) >> inode->i_blkbits;
@@ -173,7 +168,8 @@ static void
iomap_read_page_end_io(struct bio_vec *bvec, int error)
{
struct page *page = bvec->bv_page;
- struct iomap_page *iop = to_iomap_page(page);
+ struct folio *folio = page_folio(page);
+ struct iomap_page *iop = to_iomap_page(folio);

if (unlikely(error)) {
ClearPageUptodate(page);
@@ -427,7 +423,8 @@ int
iomap_is_partially_uptodate(struct page *page, unsigned long from,
unsigned long count)
{
- struct iomap_page *iop = to_iomap_page(page);
+ struct folio *folio = page_folio(page);
+ struct iomap_page *iop = to_iomap_page(folio);
struct inode *inode = page->mapping->host;
unsigned len, first, last;
unsigned i;
@@ -1003,7 +1000,8 @@ static void
iomap_finish_page_writeback(struct inode *inode, struct page *page,
int error, unsigned int len)
{
- struct iomap_page *iop = to_iomap_page(page);
+ struct folio *folio = page_folio(page);
+ struct iomap_page *iop = to_iomap_page(folio);

if (error) {
SetPageError(page);
--
2.33.0