iomap: Set all uptodate bits for an Uptodate page

[ Upstream commit 4595a298d5 ]

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: 9dc55f1389 ("iomap: add support for sub-pagesize buffered I/O without buffer heads")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reported-by: Qian Cai <cai@redhat.com>
Cc: Brian Foster <bfoster@redhat.com>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2020-09-25 11:16:53 -07:00 committed by Greg Kroah-Hartman
parent 45227ae32f
commit f691ab24cf
1 changed files with 3 additions and 0 deletions

View File

@ -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