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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Jeff Layton <jlayton@kernel.org>
CC:     linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        "ceph-devel@vger.kernel.org" <ceph-devel@vger.kernel.org>,
        CIFS <linux-cifs@vger.kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>, "hch@lst.de" <hch@lst.de>
Subject: Re: [PATCH 7/7] nfsd: use locks_inode_context helper
Thread-Topic: [PATCH 7/7] nfsd: use locks_inode_context helper
Thread-Index: AQHY+c6Vlu0TAlt2Q06byNQrxnDNh65BqngA
Date:   Wed, 16 Nov 2022 15:21:05 +0000
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References: <20221116151726.129217-1-jlayton@kernel.org>
 <20221116151726.129217-8-jlayton@kernel.org>
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> On Nov 16, 2022, at 10:17 AM, Jeff Layton <jlayton@kernel.org> wrote:
>=20
> nfsd currently doesn't access i_flctx safely everywhere. This requires a
> smp_load_acquire, as the pointer is set via cmpxchg (a release
> operation).
>=20
> Cc: Chuck Lever <chuck.lever@oracle.com>
> Signed-off-by: Jeff Layton <jlayton@kernel.org>

Acked-by: Chuck Lever <chuck.lever@oracle.com>


> ---
> fs/nfsd/nfs4state.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>=20
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 836bd825ca4a..da8d0ea66229 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -4758,7 +4758,7 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsi=
gned int deny_type)
>=20
> static bool nfsd4_deleg_present(const struct inode *inode)
> {
> -	struct file_lock_context *ctx =3D smp_load_acquire(&inode->i_flctx);
> +	struct file_lock_context *ctx =3D locks_inode_context(inode);
>=20
> 	return ctx && !list_empty_careful(&ctx->flc_lease);
> }
> @@ -5897,7 +5897,7 @@ nfs4_lockowner_has_blockers(struct nfs4_lockowner *=
lo)
>=20
> 	list_for_each_entry(stp, &lo->lo_owner.so_stateids, st_perstateowner) {
> 		nf =3D stp->st_stid.sc_file;
> -		ctx =3D nf->fi_inode->i_flctx;
> +		ctx =3D locks_inode_context(nf->fi_inode);
> 		if (!ctx)
> 			continue;
> 		if (locks_owner_has_blockers(ctx, lo))
> @@ -7713,7 +7713,7 @@ check_for_locks(struct nfs4_file *fp, struct nfs4_l=
ockowner *lowner)
> 	}
>=20
> 	inode =3D locks_inode(nf->nf_file);
> -	flctx =3D inode->i_flctx;
> +	flctx =3D locks_inode_context(inode);
>=20
> 	if (flctx && !list_empty_careful(&flctx->flc_posix)) {
> 		spin_lock(&flctx->flc_lock);
> --=20
> 2.38.1
>=20

--
Chuck Lever