From f691ab24cf1996eae27d44cf74a234a72f6b5111 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Fri, 25 Sep 2020 11:16:53 -0700 Subject: [PATCH] iomap: Set all uptodate bits for an Uptodate page [ Upstream commit 4595a298d5563cf76c1d852970f162051fd1a7a6 ] For filesystems with block size < page size, we need to set all the per-block uptodate bits if the page was already uptodate at the time we create the per-block metadata. This can happen if the page is invalidated (eg by a write to drop_caches) but ultimately not removed from the page cache. This is a data corruption issue as page writeback skips blocks which are marked !uptodate. Fixes: 9dc55f1389f9 ("iomap: add support for sub-pagesize buffered I/O without buffer heads") Signed-off-by: Matthew Wilcox (Oracle) Reported-by: Qian Cai Cc: Brian Foster Reviewed-by: Gao Xiang Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Sasha Levin --- fs/iomap/buffered-io.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 53cd7b2bb580..c28ba474a25e 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -23,6 +23,7 @@ static struct iomap_page * iomap_page_create(struct inode *inode, struct page *page) { struct iomap_page *iop = to_iomap_page(page); + unsigned int nr_blocks = PAGE_SIZE / i_blocksize(inode); if (iop || i_blocksize(inode) == PAGE_SIZE) return iop; @@ -32,6 +33,8 @@ iomap_page_create(struct inode *inode, struct page *page) atomic_set(&iop->write_count, 0); spin_lock_init(&iop->uptodate_lock); bitmap_zero(iop->uptodate, PAGE_SIZE / SECTOR_SIZE); + if (PageUptodate(page)) + bitmap_fill(iop->uptodate, nr_blocks); /* * migrate_page_move_mapping() assumes that pages with private data have