From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 CE8344EE86A for ; Fri, 25 Sep 2026 23:51:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790380308; cv=none; b=p3WvhQHJzRLVCqKVxjFb9GF5S4YYmQAyTX1yt2XpDSFSAse2jysKmfjbk87OZzoBFdw7fRIgDRYH79UMf69dMrkga2V9VEE23yxfD1/HlSRdMdI4RWTWXeCBUuXtKzyApXNCX6E4Cr+UdMsbsiHGbZyh8rMDE/+Br/5k8BfGXKg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790380308; c=relaxed/simple; bh=4i+9p3rEiuuNDim3PbcMfT0JwpJfBD/+abfZMG2ISgw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=fpmDGvfDBsddXiNLIszgEk2fwIR+w20juLtmIX9rODhevhEujoIxtbZsJQYYqkSbyqQbG2++PR9RS0p/obc8Uw065KbLo3WZZUjjdhlL8t/VJw3IKQSbzAxufTF5070Vaefqwh+kbuRtH47Rb8qB2/uRHwJ4tXeg8JEi0l2GBac= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=i828E3Nb; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="i828E3Nb" Received: by smtp.kernel.org (Postfix) with UTF8SMTPSA id A8A901F000FF; Fri, 25 Sep 2026 23:51:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790380306; bh=08xK5Yp8kZrfpkwyj0Yu1Wg44uG8YeFGM0hdv9x0IF8=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=i828E3NberWX2aCOj6ug8SZYxxvQi3Cfjin6euNsvjh9QY+it+M4PSPn9B1arQbgL RJhjWGreH5LK+SPF/Ie9/sFj++z/Jl42HMtx5NLwGtipvfN2weBXOrAiNuxHuTHxDW dXa7RXzA2byORnzp06erDWtPOYG9g0sNb0MfJ+0TOgy7DHMbT7baYovMlaYt2N11eo eYy4521JCWXyIGp7vt20WPCEScKwePc+ky08rKCc2fb5mGu9v9lTjouYDNh1mo2eEP EiM3IaKy54LKkxGjaS9d943ROpX1MTH1dwtiPTIgL/vdca6dpGKaFGP+0fFzhOF8S0 Z7S4aVItfFcbw== Date: Fri, 25 Sep 2026 16:51:46 -0700 From: "Darrick J. Wong" To: Christoph Hellwig Cc: Andrey Albershteyn , linux-xfs@vger.kernel.org Subject: Re: [PATCH 32/32] xfs_scrub: don't merge over unused space when data checksums are enabled Message-ID: <20260925235146.GQ2705364@frogsfrogsfrogs> References: <20260924100512.2733748-1-hch@lst.de> <20260924100512.2733748-33-hch@lst.de> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260924100512.2733748-33-hch@lst.de> On Thu, Sep 24, 2026 at 12:04:22PM +0200, Christoph Hellwig wrote: > Unused space could be lost space at mount time for which no metadata was > recorded, and we thus might not have valid checksums for it. > > Signed-off-by: Christoph Hellwig > --- Pretty straightforward! Reviewed-by: "Darrick J. Wong" --D > scrub/read_verify.c | 33 +++++++++++++++++++++++---------- > 1 file changed, 23 insertions(+), 10 deletions(-) > > diff --git a/scrub/read_verify.c b/scrub/read_verify.c > index 311ea1c29008..0c3bec104d16 100644 > --- a/scrub/read_verify.c > +++ b/scrub/read_verify.c > @@ -542,20 +542,33 @@ try_read_verify_schedule_io( > > /* > * If we have a stashed IO, we haven't changed pools, the error > - * reporting is the same, and the two extents are close, > - * we can combine them. > + * reporting is the same, and the two extents are close, we can combine > + * them. > + * > + * If the file system has data checksums enabled, only merge fully > + * contigous ranges, as unused data might have invalid checksums. > */ > - if (rs->rvp == rvp && rs->io_length > 0 && > - ((start >= rs->io_start && start <= rv_end + locality) || > - (rs->io_start >= start && > - rs->io_start <= req_end + locality))) { > - rs->io_start = min(rs->io_start, start); > - rs->io_length = max(req_end, rv_end) - rs->io_start; > - > - return true; > + if (rs->rvp != rvp || !rs->io_length) > + return false; > + > + if (rvp->ctx->mnt.fsgeom.flags & XFS_FSOP_GEOM_FLAGS_DATA_CSUM) { > + if (start == rv_end) > + goto merge; > + if (rs->io_start == req_end) > + goto merge; > + } else { > + if (start >= rs->io_start && start <= rv_end + locality) > + goto merge; > + if (rs->io_start >= start && rs->io_start <= req_end + locality) > + goto merge; > } > > return false; > + > +merge: > + rs->io_start = min(rs->io_start, start); > + rs->io_length = max(req_end, rv_end) - rs->io_start; > + return true; > } > > /* Did read verification succeed? */ > -- > 2.53.0 > >