From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 4847B53BE; Mon, 24 Feb 2025 20:34:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740429280; cv=none; b=BUGGOpVN9KCpBMIGREzB1gzTDfBi2wT11PVxmEbuyi4lKjRuZGmaEVLuzdG3njlNelf+J3zWYd3iGYBKCeSsIYYLC41evqJYKSkISNI4nQQgkijcdEfLv78+4I+3qkMH3D63YfJbMyj8/a0wPA45sNiVU1Hpa9CWFeOvz+34dBU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740429280; c=relaxed/simple; bh=OkOIAmiNS5JkHWp5A+/lqYYPSgryUahmnDVidue35Os=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QLDbb2UYFAgu5DLW/NyMEwz3Tl+wO0ObUVVz+NJ+tfbFW6yqk2CsTA0t22xYrlsd2S56bE682eK4ETO10vig/tfT0TNV6LUcYetC2S7A/A8vXfN28Sz3fxxAEqi1rZ0G+Wf61rNIV4tsRxMQplg5HUvB5bE7kBTzPTSl8PjhqkA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Fq1VY3Jj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Fq1VY3Jj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ABA94C4CED6; Mon, 24 Feb 2025 20:34:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740429279; bh=OkOIAmiNS5JkHWp5A+/lqYYPSgryUahmnDVidue35Os=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Fq1VY3JjsuyteXGzn/gcCxuJyRatKKHsnCTiFek1U+e8tZOk7fWPCNR+thyAVbp5Y alXzPwLiUv6Sx5e5yP3GrLLB38AFNv43YOOqpcvx4nzBbS+HeSIbk/1NgHK6jO/NJk ScqB3JbwnYAq8NZET0VbWH/sZAtf9IYH0qnOdRB+yZjnZc3cs5FxlWLqvedoEHXCnK Z0L64EB06Gsvbft4drJzFiV2hB9MVKu9pEwLS5BEhN8qDwCGCNGEx5OZsyN/nnKKkJ W/GUs9RJd1CBjixuuW4xv2mzyrQipA+yG5Arjxi9J25vwdptqI24ezpqqfEiWKOoAX 26pS/qAmOOPwA== Date: Mon, 24 Feb 2025 12:34:39 -0800 From: "Darrick J. Wong" To: John Garry Cc: brauner@kernel.org, cem@kernel.org, dchinner@redhat.com, hch@lst.de, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, ojaswin@linux.ibm.com, ritesh.list@gmail.com, martin.petersen@oracle.com, tytso@mit.edu, linux-ext4@vger.kernel.org Subject: Re: [PATCH v2 10/11] xfs: Update atomic write max size Message-ID: <20250224203439.GK21808@frogsfrogsfrogs> References: <20250213135619.1148432-1-john.g.garry@oracle.com> <20250213135619.1148432-11-john.g.garry@oracle.com> Precedence: bulk X-Mailing-List: linux-fsdevel@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: <20250213135619.1148432-11-john.g.garry@oracle.com> On Thu, Feb 13, 2025 at 01:56:18PM +0000, John Garry wrote: > Now that CoW-based atomic writes are supported, update the max size of an > atomic write. > > For simplicity, limit at the max of what the mounted bdev can support in > terms of atomic write limits. Maybe in future we will have a better way > to advertise this optimised limit. > > In addition, the max atomic write size needs to be aligned to the agsize. > Limit the size of atomic writes to the greatest power-of-two factor of the > agsize so that allocations for an atomic write will always be aligned > compatibly with the alignment requirements of the storage. > > For RT inode, just limit to 1x block, even though larger can be supported > in future. > > Signed-off-by: John Garry > --- > fs/xfs/xfs_iops.c | 13 ++++++++++++- > fs/xfs/xfs_iops.h | 1 - > fs/xfs/xfs_mount.c | 28 ++++++++++++++++++++++++++++ > fs/xfs/xfs_mount.h | 1 + > 4 files changed, 41 insertions(+), 2 deletions(-) > > diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c > index ea79fb246e33..d0a537696514 100644 > --- a/fs/xfs/xfs_iops.c > +++ b/fs/xfs/xfs_iops.c > @@ -606,12 +606,23 @@ xfs_get_atomic_write_attr( > unsigned int *unit_min, > unsigned int *unit_max) > { > + struct xfs_buftarg *target = xfs_inode_buftarg(ip); > + struct xfs_mount *mp = ip->i_mount; > + > if (!xfs_inode_can_atomicwrite(ip)) { > *unit_min = *unit_max = 0; > return; > } > > - *unit_min = *unit_max = ip->i_mount->m_sb.sb_blocksize; > + *unit_min = ip->i_mount->m_sb.sb_blocksize; > + > + if (XFS_IS_REALTIME_INODE(ip)) { > + /* For now, set limit at 1x block */ > + *unit_max = ip->i_mount->m_sb.sb_blocksize; > + } else { > + *unit_max = min_t(unsigned int, XFS_FSB_TO_B(mp, mp->awu_max), > + target->bt_bdev_awu_max); > + } > } > > static void > diff --git a/fs/xfs/xfs_iops.h b/fs/xfs/xfs_iops.h > index ce7bdeb9a79c..d95a543f3ab0 100644 > --- a/fs/xfs/xfs_iops.h > +++ b/fs/xfs/xfs_iops.h > @@ -22,5 +22,4 @@ extern void xfs_diflags_to_iflags(struct xfs_inode *ip, bool init); > void xfs_get_atomic_write_attr(struct xfs_inode *ip, > unsigned int *unit_min, unsigned int *unit_max); > > - No need to remove a blank line. > #endif /* __XFS_IOPS_H__ */ > diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c > index 477c5262cf91..af3ed135be4d 100644 > --- a/fs/xfs/xfs_mount.c > +++ b/fs/xfs/xfs_mount.c > @@ -651,6 +651,32 @@ xfs_agbtree_compute_maxlevels( > levels = max(levels, mp->m_rmap_maxlevels); > mp->m_agbtree_maxlevels = max(levels, mp->m_refc_maxlevels); > } > +static inline void > +xfs_compute_awu_max( > + struct xfs_mount *mp) > +{ > + xfs_agblock_t agsize = mp->m_sb.sb_agblocks; > + xfs_agblock_t awu_max; > + > + if (!xfs_has_reflink(mp)) { > + mp->awu_max = 1; > + return; > + } > + > + /* > + * Find highest power-of-2 evenly divisible into agsize and which > + * also fits into an unsigned int field. > + */ > + awu_max = 1; > + while (1) { > + if (agsize % (awu_max * 2)) > + break; > + if (XFS_FSB_TO_B(mp, awu_max * 2) > UINT_MAX) > + break; > + awu_max *= 2; > + } > + mp->awu_max = awu_max; > +} > > /* Compute maximum possible height for realtime btree types for this fs. */ > static inline void > @@ -736,6 +762,8 @@ xfs_mountfs( > xfs_agbtree_compute_maxlevels(mp); > xfs_rtbtree_compute_maxlevels(mp); > > + xfs_compute_awu_max(mp); > + > /* > * Check if sb_agblocks is aligned at stripe boundary. If sb_agblocks > * is NOT aligned turn off m_dalign since allocator alignment is within > diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h > index fbed172d6770..34286c87ac4a 100644 > --- a/fs/xfs/xfs_mount.h > +++ b/fs/xfs/xfs_mount.h > @@ -198,6 +198,7 @@ typedef struct xfs_mount { > bool m_fail_unmount; > bool m_finobt_nores; /* no per-AG finobt resv. */ > bool m_update_sb; /* sb needs update in mount */ > + xfs_extlen_t awu_max; /* max atomic write */ Might want to clarify that this is for the *data* device. /* max atomic write to datadev */ With those two things fixed, Reviewed-by: "Darrick J. Wong" --D > > /* > * Bitsets of per-fs metadata that have been checked and/or are sick. > -- > 2.31.1 > >