Return-Path: Received: from mail-vx0-f174.google.com ([209.85.220.174]:39011 "EHLO mail-vx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752512Ab1GKUIz (ORCPT ); Mon, 11 Jul 2011 16:08:55 -0400 Received: by vxb39 with SMTP id 39so2956360vxb.19 for ; Mon, 11 Jul 2011 13:08:55 -0700 (PDT) Date: Mon, 11 Jul 2011 16:08:51 -0400 From: Jeff Layton To: bjschuma@netapp.com Cc: Trond.Myklebust@netapp.com, linux-nfs@vger.kernel.org Subject: Re: [PATCH 2/2] NFS: Send SIGIO on lost locks Message-ID: <20110711160851.13814fa1@tlielax.poochiereds.net> In-Reply-To: <1310407110-20600-2-git-send-email-bjschuma@netapp.com> References: <1310407110-20600-1-git-send-email-bjschuma@netapp.com> <1310407110-20600-2-git-send-email-bjschuma@netapp.com> Content-Type: text/plain; charset=US-ASCII Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On Mon, 11 Jul 2011 13:58:30 -0400 bjschuma@netapp.com wrote: > From: Bryan Schumaker > > If the client loses a lock, we send SIGIO to the application to notify > it. The application can then handle the error from there. > > Signed-off-by: Bryan Schumaker Would SIGLOST be a better choice? Linux hasn't supported that historically, but we could add it. > --- > Documentation/kernel-parameters.txt | 7 +++++++ > fs/nfs/nfs4_fs.h | 2 ++ > fs/nfs/nfs4proc.c | 13 +++++++++++++ > fs/nfs/nfs4state.c | 14 ++++++++++++++ > fs/nfs/write.c | 7 +++++++ > 5 files changed, 43 insertions(+), 0 deletions(-) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index fd248a31..988ebdc 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -1593,6 +1593,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > of returning the full 64-bit number. > The default is to return 64-bit inode numbers. > > + nfs.enable_sigio= > + [NFSv4.1] enable sending SIGIO to applications. > + If true, the NFS client will send SIGIO to applications > + when a lost file lock is detected. If false, the client > + will attempt to recover the lock. > + The default is to send SIGIO. > + > nfs.nfs4_disable_idmapping= > [NFSv4] When set, this option disables the NFSv4 > idmapper on the client, but only if the mount > diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h > index c30aed2..8fa02af 100644 > --- a/fs/nfs/nfs4_fs.h > +++ b/fs/nfs/nfs4_fs.h > @@ -163,6 +163,7 @@ struct nfs4_lock_state { > struct list_head ls_locks; /* Other lock stateids */ > struct nfs4_state * ls_state; /* Pointer to open state */ > #define NFS_LOCK_INITIALIZED 1 > +#define NFS_LOCK_INVALID 2 > int ls_flags; > struct nfs_seqid_counter ls_seqid; > struct rpc_sequence ls_sequence; > @@ -346,6 +347,7 @@ extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state > extern void nfs4_put_open_state(struct nfs4_state *); > extern void nfs4_close_state(struct path *, struct nfs4_state *, fmode_t); > extern void nfs4_close_sync(struct path *, struct nfs4_state *, fmode_t); > +extern int nfs4_validate_lock_stateid(struct nfs4_state *, struct nfs_lock_context *); > extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t); > extern void nfs4_schedule_lease_recovery(struct nfs_client *); > extern void nfs4_schedule_state_manager(struct nfs_client *); > diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c > index f37218b..8757dbd 100644 > --- a/fs/nfs/nfs4proc.c > +++ b/fs/nfs/nfs4proc.c > @@ -4462,6 +4462,8 @@ out: > } > > #if defined(CONFIG_NFS_V4_1) > +bool enable_sigio = true; > + > static int nfs41_lock_expired(struct nfs4_state *state, struct file_lock *request) > { > int status; > @@ -4472,10 +4474,21 @@ static int nfs41_lock_expired(struct nfs4_state *state, struct file_lock *reques > status = nfs41_test_stateid(server, stateid); > if (status == NFS_OK) > return 0; > + > nfs41_free_stateid(server, stateid); > lock_state->ls_seqid.flags &= !NFS_SEQID_CONFIRMED; > + > + if (enable_sigio) { > + lock_state->ls_flags |= NFS_LOCK_INVALID; > + kill_pid(request->fl_nspid, SIGIO, 1); > + return 0; > + } > return nfs4_lock_expired(state, request); > } > + > +module_param(enable_sigio, bool, 0644); > +MODULE_PARM_DESC(enable_sigio, "Send SIGIO to an application when a lost lock" > + "is detected instead of attempting recovery"); > #endif > > static int _nfs4_proc_setlk(struct nfs4_state *state, int cmd, struct file_lock *request) > diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c > index 5d744a5..101d9b4 100644 > --- a/fs/nfs/nfs4state.c > +++ b/fs/nfs/nfs4state.c > @@ -725,6 +725,20 @@ __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_p > return NULL; > } > > +int nfs4_validate_lock_stateid(struct nfs4_state *state, struct nfs_lock_context *lock_ctx) > +{ > + int valid = 1; > + struct nfs4_lock_state *lock_state; > + > + spin_lock(&state->state_lock); > + lock_state = __nfs4_find_lock_state(state, lock_ctx->lockowner, lock_ctx->pid, NFS4_ANY_LOCK_TYPE); > + if (lock_state != NULL) > + valid = (lock_state->ls_flags & NFS_LOCK_INVALID) == 0; > + spin_unlock(&state->state_lock); > + nfs4_put_lock_state(lock_state); > + return valid; > +} > + > /* > * Return a compatible lock_state. If no initialized lock_state structure > * exists, return an uninitialized one. > diff --git a/fs/nfs/write.c b/fs/nfs/write.c > index 7f8732e..49ca975 100644 > --- a/fs/nfs/write.c > +++ b/fs/nfs/write.c > @@ -1114,7 +1114,14 @@ out: > void nfs_write_prepare(struct rpc_task *task, void *calldata) > { > struct nfs_write_data *data = calldata; > + struct nfs4_state *state = data->args.context->state; > + struct nfs_lock_context *lock_context = data->args.lock_context; > > + if (!nfs4_validate_lock_stateid(state, lock_context)) { > + task->tk_status = -EIO; > + task->tk_action = NULL; > + return; > + } > if (nfs4_setup_sequence(NFS_SERVER(data->inode), > &data->args.seq_args, > &data->res.seq_res, 1, task)) -- Jeff Layton