On Wed, Oct 16, 2019 at 05:06:04PM +1100, Dave Chinner wrote: > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 516faa280ced..e9dc52537e5b 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -3523,9 +3523,16 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > return ret; > } > > + /* > + * Writes that span EOF might trigger an IO size update on completion, > + * so consider them to be dirty for the purposes of O_DSYNC even if > + * there is no other metadata changes being made or are pending here. > + */ > iomap->flags = 0; > - if (ext4_inode_datasync_dirty(inode)) > + if (ext4_inode_datasync_dirty(inode) || > + offset + length > i_size_read(inode)) > iomap->flags |= IOMAP_F_DIRTY; > + > iomap->bdev = inode->i_sb->s_bdev; > iomap->dax_dev = sbi->s_daxdev; > iomap->offset = (u64)first_block << blkbits; Ext4 is not currently using iomap for any kind of writing right now, so perhaps this should land via Matthew's patchset? - Ted
