From 009d8d849d3ff59b1a23d2df2c55f2130b2ec7f2 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 17 Oct 2019 13:12:12 -0700 Subject: iomap: zero newly allocated mapped blocks File systems like gfs2 don't support delayed allocations or unwritten extents and thus allocate normal mapped blocks to fill holes. To cover the case of such file systems allocating new blocks to fill holes also zero out mapped blocks with the new flag. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/iomap/buffered-io.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index e25901ae3ff4..181ee8477aad 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -203,6 +203,14 @@ iomap_read_inline_data(struct inode *inode, struct page *page, SetPageUptodate(page); } +static inline bool iomap_block_needs_zeroing(struct inode *inode, + struct iomap *iomap, loff_t pos) +{ + return iomap->type != IOMAP_MAPPED || + (iomap->flags & IOMAP_F_NEW) || + pos >= i_size_read(inode); +} + static loff_t iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, struct iomap *iomap) @@ -226,7 +234,7 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, if (plen == 0) goto done; - if (iomap->type != IOMAP_MAPPED || pos >= i_size_read(inode)) { + if (iomap_block_needs_zeroing(inode, iomap, pos)) { zero_user(page, poff, plen); iomap_set_range_uptodate(page, poff, plen); goto done; @@ -532,7 +540,7 @@ iomap_read_page_sync(struct inode *inode, loff_t block_start, struct page *page, struct bio_vec bvec; struct bio bio; - if (iomap->type != IOMAP_MAPPED || block_start >= i_size_read(inode)) { + if (iomap_block_needs_zeroing(inode, iomap, block_start)) { zero_user_segments(page, poff, from, to, poff + plen); iomap_set_range_uptodate(page, poff, plen); return 0; -- cgit v1.2.3