[PATCH v2 1/2] iomap: add helper to mark folio uptodate

[Joanne Koong <joannelkoong@gmail.com>]

Add an exported helper iomap_folio_mark_uptodate() to mark a folio as
uptodate and update its uptodate bitmap if the folio has iomap state
data attached.

This is needed because there are some filesystems (eg fuse) that have
paths outside of conventional iomap calls that need to mark a folio as
uptodate (eg writing server-pushed data directly into the page cache)
and need the iomap-internal uptodate bitmap to be in sync with the
uptodate state of the folio.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
---
 fs/iomap/buffered-io.c | 6 ++++++
 include/linux/iomap.h  | 1 +
 2 files changed, 7 insertions(+)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 8d4806dc46d4..bc33c34800e8 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -105,6 +105,12 @@ static void iomap_set_range_uptodate(struct folio *folio, size_t off,
 		folio_mark_uptodate(folio);
 }
 
+void iomap_folio_mark_uptodate(struct folio *folio)
+{
+	iomap_set_range_uptodate(folio, 0, folio_size(folio));
+}
+EXPORT_SYMBOL_GPL(iomap_folio_mark_uptodate);
+
 /*
  * Find the next dirty block in the folio. end_blk is inclusive.
  * If no dirty block is found, this will return end_blk + 1.
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 3582ed1fe236..21e73cb9c51e 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -365,6 +365,7 @@ struct folio *iomap_get_folio(struct iomap_iter *iter, loff_t pos, size_t len);
 bool iomap_release_folio(struct folio *folio, gfp_t gfp_flags);
 void iomap_invalidate_folio(struct folio *folio, size_t offset, size_t len);
 bool iomap_dirty_folio(struct address_space *mapping, struct folio *folio);
+void iomap_folio_mark_uptodate(struct folio *folio);
 int iomap_file_unshare(struct inode *inode, loff_t pos, loff_t len,
 		const struct iomap_ops *ops,
 		const struct iomap_write_ops *write_ops);
-- 
2.52.0