Return-Path: Received: from mx2.suse.de ([195.135.220.15]:42620 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752679AbdLLW5S (ORCPT ); Tue, 12 Dec 2017 17:57:18 -0500 From: NeilBrown To: Trond Myklebust , Anna Schumaker Date: Wed, 13 Dec 2017 09:57:09 +1100 Cc: linux-nfs@vger.kernel.org Subject: [PATCH] NFSv4: always set NFS_LOCK_LOST when a lock is lost. Message-ID: <87r2rzo8qi.fsf@notabene.neil.brown.name> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Sender: linux-nfs-owner@vger.kernel.org List-ID: --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable There are 2 comments in the NFSv4 code which suggest that SIGLOST should possibly be sent to a process. In these cases a lock has been lost. The current practice is to set NFS_LOCK_LOST so that read/write returns EIO when a lock is lost. So change these comments to code when sets NFS_LOCK_LOST. One case is when lock recovery after apparent server restart fails with NFS4ERR_DENIED, NFS4ERR_RECLAIM_BAD, or NFS4ERRO_RECLAIM_CONFLICT. The other case is when a lock attempt as part of lease recovery fails with NFS4ERR_DENIED. In an ideal world, these should not happen. However I have a packet trace showing an NFSv4.1 session getting NFS4ERR_BADSESSION after an extended network parition. The NFSv4.1 client treats this like server reboot until/unless it get NFS4ERR_NO_GRACE, in which case it switches over to "nograce" recovery mode. In this network trace, the client attempts to recover a lock and the server (incorrectly) reports NFS4ERR_DENIED rather than NFS4ERR_NO_GRACE. This leads to the ineffective comment and the client then continues to write using the OPEN stateid. Signed-off-by: NeilBrown =2D-- Note that I have not tested this as I do not have direct access to a faulty NFS server. Once I get confirmation I will provide an update. NeilBrown fs/nfs/nfs4proc.c | 12 ++++++++---- fs/nfs/nfs4state.c | 5 ++++- 2 files changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 56fa5a16e097..083802f7a1e9 100644 =2D-- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2019,7 +2019,7 @@ static int nfs4_open_reclaim(struct nfs4_state_owner = *sp, struct nfs4_state *sta return ret; } =20 =2Dstatic int nfs4_handle_delegation_recall_error(struct nfs_server *server= , struct nfs4_state *state, const nfs4_stateid *stateid, int err) +static int nfs4_handle_delegation_recall_error(struct nfs_server *server, = struct nfs4_state *state, const nfs4_stateid *stateid, struct file_lock *fl= , int err) { switch (err) { default: @@ -2066,7 +2066,11 @@ static int nfs4_handle_delegation_recall_error(struc= t nfs_server *server, struct return -EAGAIN; case -ENOMEM: case -NFS4ERR_DENIED: =2D /* kill_proc(fl->fl_pid, SIGLOST, 1); */ + if (fl) { + struct nfs4_lock_state *lsp =3D fl->fl_u.nfs4_fl.owner; + if (lsp) + set_bit(NFS_LOCK_LOST, &lsp->ls_flags); + } return 0; } return err; @@ -2102,7 +2106,7 @@ int nfs4_open_delegation_recall(struct nfs_open_conte= xt *ctx, err =3D nfs4_open_recover_helper(opendata, FMODE_READ); } nfs4_opendata_put(opendata); =2D return nfs4_handle_delegation_recall_error(server, state, stateid, err); + return nfs4_handle_delegation_recall_error(server, state, stateid, NULL, = err); } =20 static void nfs4_open_confirm_prepare(struct rpc_task *task, void *calldat= a) @@ -6739,7 +6743,7 @@ int nfs4_lock_delegation_recall(struct file_lock *fl,= struct nfs4_state *state, if (err !=3D 0) return err; err =3D _nfs4_do_setlk(state, F_SETLK, fl, NFS_LOCK_NEW); =2D return nfs4_handle_delegation_recall_error(server, state, stateid, err); + return nfs4_handle_delegation_recall_error(server, state, stateid, fl, er= r); } =20 struct nfs_release_lockowner_data { diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index e4f4a09ed9f4..91a4d4eeb235 100644 =2D-- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1482,6 +1482,7 @@ static int nfs4_reclaim_locks(struct nfs4_state *stat= e, const struct nfs4_state_ struct inode *inode =3D state->inode; struct nfs_inode *nfsi =3D NFS_I(inode); struct file_lock *fl; + struct nfs4_lock_state *lsp; int status =3D 0; struct file_lock_context *flctx =3D inode->i_flctx; struct list_head *list; @@ -1522,7 +1523,9 @@ static int nfs4_reclaim_locks(struct nfs4_state *stat= e, const struct nfs4_state_ case -NFS4ERR_DENIED: case -NFS4ERR_RECLAIM_BAD: case -NFS4ERR_RECLAIM_CONFLICT: =2D /* kill_proc(fl->fl_pid, SIGLOST, 1); */ + lsp =3D fl->fl_u.nfs4_fl.owner; + if (lsp) + set_bit(NFS_LOCK_LOST, &lsp->ls_flags); status =3D 0; } spin_lock(&flctx->flc_lock); =2D-=20 2.14.0.rc0.dirty --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEG8Yp69OQ2HB7X0l6Oeye3VZigbkFAlowXsYACgkQOeye3VZi gbksAxAAtLV2Uz6nzcRvlckUySJGxTH19PRMSM0bfTt9NAPYDErf9cT3CTUcj51N NcwztNvhTcTyFrtwAKQNDAZkbvujfXPzYMVtC36atRxc3RiX9XawawJmI80A6aXV 8uosDR4GRTkxzsHlGD3+JmEl7KzYOyGezm5pF/Ee0FG5Q31519V23PY52duvAGg2 3VMNnVRPgq+wSrBpeXajzDzJi9qCp7xyNei3D/q6UPIEeZXIKD5/qO4PqeaDXDBC cMzIZYlYd0XPyEAtwFI83VTls619Bb0igP2xVqEGZpGWNoSLICfNUV3sUegRqIsb 8VFcINdAcOndNrMeX3aU4cZVo5+H5INR5WMj6VH17y8X135FiTIyMBt+dvunvFdk 3dbcZaJGpdVUv9hIemXVWJNq62wZK523qnR434w6xdVilkJ9TUGgCV52nD0hOBBU NF0tBHDZoYkrPsBqIfsCVXcZo7/9asdTBNdX1O53wrWa7kFQDHE7uqXSFVjf32BB TxVdRFANW5jMGmcZnqabXRCqXP0ZVDN7xt7K32E3EPIh6y0o7NzlEGYmwwUsBTUw rY9vjQZVaO0xNWi9NT0oT0fZ8uh3rIcRScnZG8MMzky13jLr8dJ95jhVuCKzmhMH H2v+7G+J228OtCmlLSMMGa/JgqSAs6XDhIlBxkBai6oewOQN8gA= =nmpr -----END PGP SIGNATURE----- --=-=-=--