From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DFD3A3FC1 for ; Thu, 2 Sep 2021 07:32:18 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 116426736F; Thu, 2 Sep 2021 09:32:16 +0200 (CEST) Date: Thu, 2 Sep 2021 09:32:15 +0200 From: Christoph Hellwig To: Shiyang Ruan Cc: djwong@kernel.org, hch@lst.de, linux-xfs@vger.kernel.org, dan.j.williams@intel.com, david@fromorbit.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev, rgoldwyn@suse.de, viro@zeniv.linux.org.uk, willy@infradead.org, Ritesh Harjani Subject: Re: [PATCH v8 4/7] fsdax: Add dax_iomap_cow_copy() for dax_iomap_zero Message-ID: <20210902073215.GC13867@lst.de> References: <20210829122517.1648171-1-ruansy.fnst@fujitsu.com> <20210829122517.1648171-5-ruansy.fnst@fujitsu.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210829122517.1648171-5-ruansy.fnst@fujitsu.com> User-Agent: Mutt/1.5.17 (2007-11-01) On Sun, Aug 29, 2021 at 08:25:14PM +0800, Shiyang Ruan wrote: > Punch hole on a reflinked file needs dax_iomap_cow_copy() too. > Otherwise, data in not aligned area will be not correct. So, add the > srcmap to dax_iomap_zero() and replace memset() as dax_iomap_cow_copy(). > > Signed-off-by: Shiyang Ruan > Reviewed-by: Ritesh Harjani > Reviewed-by: Darrick J. Wong > --- > fs/dax.c | 26 ++++++++++++++++---------- > fs/iomap/buffered-io.c | 4 ++-- > include/linux/dax.h | 3 ++- > 3 files changed, 20 insertions(+), 13 deletions(-) > > diff --git a/fs/dax.c b/fs/dax.c > index f4acb79cb811..b294900e574e 100644 > --- a/fs/dax.c > +++ b/fs/dax.c > @@ -1209,7 +1209,8 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf, > } > #endif /* CONFIG_FS_DAX_PMD */ > > -s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap) > +s64 dax_iomap_zero(loff_t pos, u64 length, const struct iomap *iomap, > + const struct iomap *srcmap) We can in fact pass the iomap_iter here as well. (probably as a prep patch). > if (page_aligned) > rc = dax_zero_page_range(iomap->dax_dev, pgoff, 1); > - else > + else { > rc = dax_direct_access(iomap->dax_dev, pgoff, 1, &kaddr, NULL); I'd clean this up a bit by doing: id = dax_read_lock(); if (page_aligned) { rc = dax_zero_page_range(iomap->dax_dev, pgoff, 1); goto out; } // non aligned case here without extra indentation or checks