On Tue, Jun 25, 2019 at 12:07:01PM +0200, Christoph Hellwig wrote: > On Mon, Jun 24, 2019 at 07:57:07AM -0700, Darrick J. Wong wrote: > > On Mon, Jun 24, 2019 at 07:52:45AM +0200, Christoph Hellwig wrote: > > > Currently we don't overwrite the flags field in the iomap in > > > xfs_bmbt_to_iomap. This works fine with 0-initialized iomaps on stack, > > > but is harmful once we want to be able to reuse an iomap in the > > > writeback code. > > > > Is that going to affect all the other iomap users, or is xfs the only > > one that assumes zero-initialized iomaps being passed into > > ->iomap_begin? > > This doesn't affect any existing user as they all get a zeroed iomap > passed from the caller in iomap.c. It affects the writeback code > once it uses struct iomap as it overwrites a previously used iomap. Then shouldn't this new writeback code zero the iomap before calling back into the filesystem, just to maintain consistent behavior? --D
