[PATCH 2/4] fs/buffer: parse IOCB_DONTCACHE flag in block_write_begin()

[Yangtao Li <frank.li@xxxxxxxx>]

When iocb flags passes IOCB_DONTCACHE, use FGP_DONTCACHE mode to get folio.

Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
---
 fs/buffer.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index f2b7b30a76ca..0ed80b62feea 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2251,11 +2251,14 @@ int block_write_begin(struct kiocb *iocb, struct address_space *mapping, loff_t
 		unsigned len, struct folio **foliop, get_block_t *get_block)
 {
 	pgoff_t index = pos >> PAGE_SHIFT;
+	fgf_t fgp = FGP_WRITEBEGIN;
 	struct folio *folio;
 	int status;
 
-	folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
-			mapping_gfp_mask(mapping));
+	if (iocb->ki_flags & IOCB_DONTCACHE)
+		fgp |= FGP_DONTCACHE;
+
+	folio = __filemap_get_folio(mapping, index, fgp, mapping_gfp_mask(mapping));
 	if (IS_ERR(folio))
 		return PTR_ERR(folio);
 
-- 
2.48.1