| Message ID | 1648182891-32599-3-git-send-email-dai.ngo@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | NFSD: Initial implementation of NFSv4 Courteous Server | expand |
On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: > Update nfs4_client to add: > . cl_cs_client_state: courtesy client state > . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state > . cl_cs_list: list used by laundromat to process courtesy clients > > Modify alloc_client to initialize these fields. > > Signed-off-by: Dai Ngo <dai.ngo@oracle.com> > --- > fs/nfsd/nfs4state.c | 2 ++ > fs/nfsd/nfsd.h | 1 + > fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ > 3 files changed, 36 insertions(+) > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index 234e852fcdfa..a65d59510681 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) > INIT_LIST_HEAD(&clp->cl_delegations); > INIT_LIST_HEAD(&clp->cl_lru); > INIT_LIST_HEAD(&clp->cl_revoked); > + INIT_LIST_HEAD(&clp->cl_cs_list); > #ifdef CONFIG_NFSD_PNFS > INIT_LIST_HEAD(&clp->cl_lo_states); > #endif > INIT_LIST_HEAD(&clp->async_copies); > spin_lock_init(&clp->async_lock); > spin_lock_init(&clp->cl_lock); > + spin_lock_init(&clp->cl_cs_lock); > rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); > return clp; > err_no_hashtbl: > diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > index 4fc1fd639527..23996c6ca75e 100644 > --- a/fs/nfsd/nfsd.h > +++ b/fs/nfsd/nfsd.h > @@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); > #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ > > #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ > +#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ > > /* > * The following attributes are currently not supported by the NFSv4 server: > diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > index 95457cfd37fc..40e390abc842 100644 > --- a/fs/nfsd/state.h > +++ b/fs/nfsd/state.h > @@ -283,6 +283,35 @@ struct nfsd4_sessionid { > #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ > > /* > + * CLIENT_ CLIENT_ CLIENT_ > + * COURTESY EXPIRED RECONNECTED Meaning Where set > + * ----------------------------------------------------------------------------- > + * | false | false | false | Confirmed, active | Default | > + * |---------------------------------------------------------------------------| > + * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | > + * | | | | Lease/lock/share | | > + * | | | | reservation conflict | | > + * | | | | can cause Courtesy | | > + * | | | | client to be expired | | > + * |---------------------------------------------------------------------------| > + * | false | true | false | Courtesy client to be| nfs4_laundromat | > + * | | | | expired by Laundromat| nfsd4_lm_lock_expired | > + * | | | | due to conflict | nfsd4_discard_courtesy_clnt | > + * | | | | | nfsd4_expire_courtesy_clnt | > + * |---------------------------------------------------------------------------| > + * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| > + * | | | | reconnected, | | > + * | | | | becoming active | | > + * ----------------------------------------------------------------------------- These are mutually exclusive values, not bits that may set to 0 or 1, so the three boolean columns are confusing. I'd just structure the table like: client state meaning where set 0 Confirmed, active Default CLIENT_COURTESY Courtesy state.... nfs4_get_client_reaplist CLIENT_EXPIRED Courtesy client to be.. nfs4_laundromat etc. --b. > + */ > + > +enum courtesy_client_state { > + NFSD4_CLIENT_COURTESY = 1, > + NFSD4_CLIENT_EXPIRED, > + NFSD4_CLIENT_RECONNECTED, > +}; > + > +/* > * struct nfs4_client - one per client. Clientids live here. > * > * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0) > @@ -385,6 +414,10 @@ struct nfs4_client { > struct list_head async_copies; /* list of async copies */ > spinlock_t async_lock; /* lock for async copies */ > atomic_t cl_cb_inflight; /* Outstanding callbacks */ > + > + enum courtesy_client_state cl_cs_client_state; > + spinlock_t cl_cs_lock; > + struct list_head cl_cs_list; > }; > > /* struct nfs4_client_reset > -- > 2.9.5
On 3/29/22 8:47 AM, J. Bruce Fields wrote: > On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: >> Update nfs4_client to add: >> . cl_cs_client_state: courtesy client state >> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state >> . cl_cs_list: list used by laundromat to process courtesy clients >> >> Modify alloc_client to initialize these fields. >> >> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> >> --- >> fs/nfsd/nfs4state.c | 2 ++ >> fs/nfsd/nfsd.h | 1 + >> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ >> 3 files changed, 36 insertions(+) >> >> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c >> index 234e852fcdfa..a65d59510681 100644 >> --- a/fs/nfsd/nfs4state.c >> +++ b/fs/nfsd/nfs4state.c >> @@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) >> INIT_LIST_HEAD(&clp->cl_delegations); >> INIT_LIST_HEAD(&clp->cl_lru); >> INIT_LIST_HEAD(&clp->cl_revoked); >> + INIT_LIST_HEAD(&clp->cl_cs_list); >> #ifdef CONFIG_NFSD_PNFS >> INIT_LIST_HEAD(&clp->cl_lo_states); >> #endif >> INIT_LIST_HEAD(&clp->async_copies); >> spin_lock_init(&clp->async_lock); >> spin_lock_init(&clp->cl_lock); >> + spin_lock_init(&clp->cl_cs_lock); >> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); >> return clp; >> err_no_hashtbl: >> diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h >> index 4fc1fd639527..23996c6ca75e 100644 >> --- a/fs/nfsd/nfsd.h >> +++ b/fs/nfsd/nfsd.h >> @@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); >> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ >> >> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ >> +#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ >> >> /* >> * The following attributes are currently not supported by the NFSv4 server: >> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h >> index 95457cfd37fc..40e390abc842 100644 >> --- a/fs/nfsd/state.h >> +++ b/fs/nfsd/state.h >> @@ -283,6 +283,35 @@ struct nfsd4_sessionid { >> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ >> >> /* >> + * CLIENT_ CLIENT_ CLIENT_ >> + * COURTESY EXPIRED RECONNECTED Meaning Where set >> + * ----------------------------------------------------------------------------- >> + * | false | false | false | Confirmed, active | Default | >> + * |---------------------------------------------------------------------------| >> + * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | >> + * | | | | Lease/lock/share | | >> + * | | | | reservation conflict | | >> + * | | | | can cause Courtesy | | >> + * | | | | client to be expired | | >> + * |---------------------------------------------------------------------------| >> + * | false | true | false | Courtesy client to be| nfs4_laundromat | >> + * | | | | expired by Laundromat| nfsd4_lm_lock_expired | >> + * | | | | due to conflict | nfsd4_discard_courtesy_clnt | >> + * | | | | | nfsd4_expire_courtesy_clnt | >> + * |---------------------------------------------------------------------------| >> + * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| >> + * | | | | reconnected, | | >> + * | | | | becoming active | | >> + * ----------------------------------------------------------------------------- > These are mutually exclusive values, not bits that may set to 0 or 1, so > the three boolean columns are confusing. I'd just structure the table > like: > > client state meaning where set > 0 Confirmed, active Default > CLIENT_COURTESY Courtesy state.... nfs4_get_client_reaplist > CLIENT_EXPIRED Courtesy client to be.. nfs4_laundromat > > etc. will fix in v19. Thanks, -Dai > > --b. > >> + */ >> + >> +enum courtesy_client_state { >> + NFSD4_CLIENT_COURTESY = 1, >> + NFSD4_CLIENT_EXPIRED, >> + NFSD4_CLIENT_RECONNECTED, >> +}; >> + >> +/* >> * struct nfs4_client - one per client. Clientids live here. >> * >> * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0) >> @@ -385,6 +414,10 @@ struct nfs4_client { >> struct list_head async_copies; /* list of async copies */ >> spinlock_t async_lock; /* lock for async copies */ >> atomic_t cl_cb_inflight; /* Outstanding callbacks */ >> + >> + enum courtesy_client_state cl_cs_client_state; >> + spinlock_t cl_cs_lock; >> + struct list_head cl_cs_list; >> }; >> >> /* struct nfs4_client_reset >> -- >> 2.9.5
On Tue, Mar 29, 2022 at 09:20:02AM -0700, dai.ngo@oracle.com wrote: > > On 3/29/22 8:47 AM, J. Bruce Fields wrote: > >On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: > >>Update nfs4_client to add: > >> . cl_cs_client_state: courtesy client state > >> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state > >> . cl_cs_list: list used by laundromat to process courtesy clients > >> > >>Modify alloc_client to initialize these fields. > >> > >>Signed-off-by: Dai Ngo <dai.ngo@oracle.com> > >>--- > >> fs/nfsd/nfs4state.c | 2 ++ > >> fs/nfsd/nfsd.h | 1 + > >> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ > >> 3 files changed, 36 insertions(+) > >> > >>diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > >>index 234e852fcdfa..a65d59510681 100644 > >>--- a/fs/nfsd/nfs4state.c > >>+++ b/fs/nfsd/nfs4state.c > >>@@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) > >> INIT_LIST_HEAD(&clp->cl_delegations); > >> INIT_LIST_HEAD(&clp->cl_lru); > >> INIT_LIST_HEAD(&clp->cl_revoked); > >>+ INIT_LIST_HEAD(&clp->cl_cs_list); > >> #ifdef CONFIG_NFSD_PNFS > >> INIT_LIST_HEAD(&clp->cl_lo_states); > >> #endif > >> INIT_LIST_HEAD(&clp->async_copies); > >> spin_lock_init(&clp->async_lock); > >> spin_lock_init(&clp->cl_lock); > >>+ spin_lock_init(&clp->cl_cs_lock); > >> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); > >> return clp; > >> err_no_hashtbl: > >>diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > >>index 4fc1fd639527..23996c6ca75e 100644 > >>--- a/fs/nfsd/nfsd.h > >>+++ b/fs/nfsd/nfsd.h > >>@@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); > >> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ > >> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ > >>+#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ > >> /* > >> * The following attributes are currently not supported by the NFSv4 server: > >>diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > >>index 95457cfd37fc..40e390abc842 100644 > >>--- a/fs/nfsd/state.h > >>+++ b/fs/nfsd/state.h > >>@@ -283,6 +283,35 @@ struct nfsd4_sessionid { > >> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ > >> /* > >>+ * CLIENT_ CLIENT_ CLIENT_ > >>+ * COURTESY EXPIRED RECONNECTED Meaning Where set > >>+ * ----------------------------------------------------------------------------- > >>+ * | false | false | false | Confirmed, active | Default | > >>+ * |---------------------------------------------------------------------------| > >>+ * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | > >>+ * | | | | Lease/lock/share | | > >>+ * | | | | reservation conflict | | > >>+ * | | | | can cause Courtesy | | > >>+ * | | | | client to be expired | | > >>+ * |---------------------------------------------------------------------------| > >>+ * | false | true | false | Courtesy client to be| nfs4_laundromat | > >>+ * | | | | expired by Laundromat| nfsd4_lm_lock_expired | > >>+ * | | | | due to conflict | nfsd4_discard_courtesy_clnt | > >>+ * | | | | | nfsd4_expire_courtesy_clnt | > >>+ * |---------------------------------------------------------------------------| > >>+ * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| > >>+ * | | | | reconnected, | | > >>+ * | | | | becoming active | | > >>+ * ----------------------------------------------------------------------------- By the way, where is a client returned to the normal (0) state? That has to happen at some point. How is CLIENT_EXPIRED treated differently from cl_time == 0, and why? Why are RECONNECTED clients discarded in so many cases? (E.g. whenever a bind_conn_to_session fails). --b. > >These are mutually exclusive values, not bits that may set to 0 or 1, so > >the three boolean columns are confusing. I'd just structure the table > >like: > > > > client state meaning where set > > 0 Confirmed, active Default > > CLIENT_COURTESY Courtesy state.... nfs4_get_client_reaplist > > CLIENT_EXPIRED Courtesy client to be.. nfs4_laundromat > > > >etc. > > will fix in v19. > > Thanks, > -Dai > > > > >--b. > > > >>+ */ > >>+ > >>+enum courtesy_client_state { > >>+ NFSD4_CLIENT_COURTESY = 1, > >>+ NFSD4_CLIENT_EXPIRED, > >>+ NFSD4_CLIENT_RECONNECTED, > >>+}; > >>+ > >>+/* > >> * struct nfs4_client - one per client. Clientids live here. > >> * > >> * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0) > >>@@ -385,6 +414,10 @@ struct nfs4_client { > >> struct list_head async_copies; /* list of async copies */ > >> spinlock_t async_lock; /* lock for async copies */ > >> atomic_t cl_cb_inflight; /* Outstanding callbacks */ > >>+ > >>+ enum courtesy_client_state cl_cs_client_state; > >>+ spinlock_t cl_cs_lock; > >>+ struct list_head cl_cs_list; > >> }; > >> /* struct nfs4_client_reset > >>-- > >>2.9.5
On Tue, Mar 29, 2022 at 12:30:11PM -0400, J. Bruce Fields wrote: > On Tue, Mar 29, 2022 at 09:20:02AM -0700, dai.ngo@oracle.com wrote: > > > > On 3/29/22 8:47 AM, J. Bruce Fields wrote: > > >On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: > > >>Update nfs4_client to add: > > >> . cl_cs_client_state: courtesy client state > > >> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state > > >> . cl_cs_list: list used by laundromat to process courtesy clients > > >> > > >>Modify alloc_client to initialize these fields. > > >> > > >>Signed-off-by: Dai Ngo <dai.ngo@oracle.com> > > >>--- > > >> fs/nfsd/nfs4state.c | 2 ++ > > >> fs/nfsd/nfsd.h | 1 + > > >> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ > > >> 3 files changed, 36 insertions(+) > > >> > > >>diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > > >>index 234e852fcdfa..a65d59510681 100644 > > >>--- a/fs/nfsd/nfs4state.c > > >>+++ b/fs/nfsd/nfs4state.c > > >>@@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) > > >> INIT_LIST_HEAD(&clp->cl_delegations); > > >> INIT_LIST_HEAD(&clp->cl_lru); > > >> INIT_LIST_HEAD(&clp->cl_revoked); > > >>+ INIT_LIST_HEAD(&clp->cl_cs_list); > > >> #ifdef CONFIG_NFSD_PNFS > > >> INIT_LIST_HEAD(&clp->cl_lo_states); > > >> #endif > > >> INIT_LIST_HEAD(&clp->async_copies); > > >> spin_lock_init(&clp->async_lock); > > >> spin_lock_init(&clp->cl_lock); > > >>+ spin_lock_init(&clp->cl_cs_lock); > > >> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); > > >> return clp; > > >> err_no_hashtbl: > > >>diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > > >>index 4fc1fd639527..23996c6ca75e 100644 > > >>--- a/fs/nfsd/nfsd.h > > >>+++ b/fs/nfsd/nfsd.h > > >>@@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); > > >> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ > > >> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ > > >>+#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ > > >> /* > > >> * The following attributes are currently not supported by the NFSv4 server: > > >>diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > > >>index 95457cfd37fc..40e390abc842 100644 > > >>--- a/fs/nfsd/state.h > > >>+++ b/fs/nfsd/state.h > > >>@@ -283,6 +283,35 @@ struct nfsd4_sessionid { > > >> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ > > >> /* > > >>+ * CLIENT_ CLIENT_ CLIENT_ > > >>+ * COURTESY EXPIRED RECONNECTED Meaning Where set > > >>+ * ----------------------------------------------------------------------------- > > >>+ * | false | false | false | Confirmed, active | Default | > > >>+ * |---------------------------------------------------------------------------| > > >>+ * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | > > >>+ * | | | | Lease/lock/share | | > > >>+ * | | | | reservation conflict | | > > >>+ * | | | | can cause Courtesy | | > > >>+ * | | | | client to be expired | | > > >>+ * |---------------------------------------------------------------------------| > > >>+ * | false | true | false | Courtesy client to be| nfs4_laundromat | > > >>+ * | | | | expired by Laundromat| nfsd4_lm_lock_expired | > > >>+ * | | | | due to conflict | nfsd4_discard_courtesy_clnt | > > >>+ * | | | | | nfsd4_expire_courtesy_clnt | > > >>+ * |---------------------------------------------------------------------------| > > >>+ * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| > > >>+ * | | | | reconnected, | | > > >>+ * | | | | becoming active | | > > >>+ * ----------------------------------------------------------------------------- > > By the way, where is a client returned to the normal (0) state? That > has to happen at some point. > > How is CLIENT_EXPIRED treated differently from cl_time == 0, and why? > > Why are RECONNECTED clients discarded in so many cases? (E.g. whenever > a bind_conn_to_session fails). A priori I just don't see how it can be right to treat a reconnected client in any way differently from an normal confirmed client. Once we've told the client that its lease is still good, we have to treat it like any other client, don't we? --b.
On 3/29/22 9:30 AM, J. Bruce Fields wrote: > On Tue, Mar 29, 2022 at 09:20:02AM -0700, dai.ngo@oracle.com wrote: >> On 3/29/22 8:47 AM, J. Bruce Fields wrote: >>> On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: >>>> Update nfs4_client to add: >>>> . cl_cs_client_state: courtesy client state >>>> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state >>>> . cl_cs_list: list used by laundromat to process courtesy clients >>>> >>>> Modify alloc_client to initialize these fields. >>>> >>>> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> >>>> --- >>>> fs/nfsd/nfs4state.c | 2 ++ >>>> fs/nfsd/nfsd.h | 1 + >>>> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ >>>> 3 files changed, 36 insertions(+) >>>> >>>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c >>>> index 234e852fcdfa..a65d59510681 100644 >>>> --- a/fs/nfsd/nfs4state.c >>>> +++ b/fs/nfsd/nfs4state.c >>>> @@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) >>>> INIT_LIST_HEAD(&clp->cl_delegations); >>>> INIT_LIST_HEAD(&clp->cl_lru); >>>> INIT_LIST_HEAD(&clp->cl_revoked); >>>> + INIT_LIST_HEAD(&clp->cl_cs_list); >>>> #ifdef CONFIG_NFSD_PNFS >>>> INIT_LIST_HEAD(&clp->cl_lo_states); >>>> #endif >>>> INIT_LIST_HEAD(&clp->async_copies); >>>> spin_lock_init(&clp->async_lock); >>>> spin_lock_init(&clp->cl_lock); >>>> + spin_lock_init(&clp->cl_cs_lock); >>>> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); >>>> return clp; >>>> err_no_hashtbl: >>>> diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h >>>> index 4fc1fd639527..23996c6ca75e 100644 >>>> --- a/fs/nfsd/nfsd.h >>>> +++ b/fs/nfsd/nfsd.h >>>> @@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); >>>> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ >>>> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ >>>> +#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ >>>> /* >>>> * The following attributes are currently not supported by the NFSv4 server: >>>> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h >>>> index 95457cfd37fc..40e390abc842 100644 >>>> --- a/fs/nfsd/state.h >>>> +++ b/fs/nfsd/state.h >>>> @@ -283,6 +283,35 @@ struct nfsd4_sessionid { >>>> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ >>>> /* >>>> + * CLIENT_ CLIENT_ CLIENT_ >>>> + * COURTESY EXPIRED RECONNECTED Meaning Where set >>>> + * ----------------------------------------------------------------------------- >>>> + * | false | false | false | Confirmed, active | Default | >>>> + * |---------------------------------------------------------------------------| >>>> + * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | >>>> + * | | | | Lease/lock/share | | >>>> + * | | | | reservation conflict | | >>>> + * | | | | can cause Courtesy | | >>>> + * | | | | client to be expired | | >>>> + * |---------------------------------------------------------------------------| >>>> + * | false | true | false | Courtesy client to be| nfs4_laundromat | >>>> + * | | | | expired by Laundromat| nfsd4_lm_lock_expired | >>>> + * | | | | due to conflict | nfsd4_discard_courtesy_clnt | >>>> + * | | | | | nfsd4_expire_courtesy_clnt | >>>> + * |---------------------------------------------------------------------------| >>>> + * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| >>>> + * | | | | reconnected, | | >>>> + * | | | | becoming active | | >>>> + * ----------------------------------------------------------------------------- > By the way, where is a client returned to the normal (0) state? That > has to happen at some point. For 4.1 courtesy client reconnects is detected in nfsd4_sequence, nfsd4_bind_conn_to_session. For 4.0 courtesy client reconnects is detected in set_client. > > How is CLIENT_EXPIRED treated differently from cl_time == 0, and why? cl_time == 0 means the client is being destroyed (almost) immediately either by the laundromat or force_expire_client. CLIENT_EXPIRED means the client will be destroyed by the laundromat and this depends on when the laundromat runs. When we set CLIENT_COURTESY we don't clear cl_time since the client is not really expired yet. We could replace CLIENT_EXPIRED with (cl_time == 0). However, to set cl_time = 0 we need to acquire the nn->client_lock which causes deadlock when we try to resolve lock conflicts from nfs4_resolve_deny_conflicts_locked (fp->fi_lock -> nn_clientlock). We use the cl_cs_lock to set CLIENT_EXPIRED. > > Why are RECONNECTED clients discarded in so many cases? (E.g. whenever > a bind_conn_to_session fails). find_in_sessionid_hashtbl: we discard the courtesy client when it reconnects and there is error from nfsd4_get_session_locked. This should be a rare condition so rather than reverting the client state back to courtesy, it is simpler just to discard it. nfsd4_create_session/find_confirmed_client: I think the only time the courtesy client sends CREATE_SESSION, before sending the SEQUENCE to reconnect after missing its leases, is when it wants to do clientid trunking. This should be a rare condition so instead of dealing with it we just do not allow it and discard the client for now. nfsd4_destroy_clientid/find_confirmed_client: instead of destroy the courtesy client here we just let the laundromat destroy it as if the client already expired. nfsd4_setclientid_confirm/find_confirmed_client: there should not be any courtesy client found from nfsd4_setclientid_confirm, it should be detected and discarded in nfsd4_setclientid. -Dai >>> These are mutually exclusive values, not bits that may set to 0 or 1, so >>> the three boolean columns are confusing. I'd just structure the table >>> like: >>> >>> client state meaning where set >>> 0 Confirmed, active Default >>> CLIENT_COURTESY Courtesy state.... nfs4_get_client_reaplist >>> CLIENT_EXPIRED Courtesy client to be.. nfs4_laundromat >>> >>> etc. >> will fix in v19. >> >> Thanks, >> -Dai >> >>> --b. >>> >>>> + */ >>>> + >>>> +enum courtesy_client_state { >>>> + NFSD4_CLIENT_COURTESY = 1, >>>> + NFSD4_CLIENT_EXPIRED, >>>> + NFSD4_CLIENT_RECONNECTED, >>>> +}; >>>> + >>>> +/* >>>> * struct nfs4_client - one per client. Clientids live here. >>>> * >>>> * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0) >>>> @@ -385,6 +414,10 @@ struct nfs4_client { >>>> struct list_head async_copies; /* list of async copies */ >>>> spinlock_t async_lock; /* lock for async copies */ >>>> atomic_t cl_cb_inflight; /* Outstanding callbacks */ >>>> + >>>> + enum courtesy_client_state cl_cs_client_state; >>>> + spinlock_t cl_cs_lock; >>>> + struct list_head cl_cs_list; >>>> }; >>>> /* struct nfs4_client_reset >>>> -- >>>> 2.9.5
On Tue, Mar 29, 2022 at 11:19:51AM -0700, dai.ngo@oracle.com wrote: > > On 3/29/22 9:30 AM, J. Bruce Fields wrote: > >On Tue, Mar 29, 2022 at 09:20:02AM -0700, dai.ngo@oracle.com wrote: > >>On 3/29/22 8:47 AM, J. Bruce Fields wrote: > >>>On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: > >>>>Update nfs4_client to add: > >>>> . cl_cs_client_state: courtesy client state > >>>> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state > >>>> . cl_cs_list: list used by laundromat to process courtesy clients > >>>> > >>>>Modify alloc_client to initialize these fields. > >>>> > >>>>Signed-off-by: Dai Ngo <dai.ngo@oracle.com> > >>>>--- > >>>> fs/nfsd/nfs4state.c | 2 ++ > >>>> fs/nfsd/nfsd.h | 1 + > >>>> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ > >>>> 3 files changed, 36 insertions(+) > >>>> > >>>>diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > >>>>index 234e852fcdfa..a65d59510681 100644 > >>>>--- a/fs/nfsd/nfs4state.c > >>>>+++ b/fs/nfsd/nfs4state.c > >>>>@@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) > >>>> INIT_LIST_HEAD(&clp->cl_delegations); > >>>> INIT_LIST_HEAD(&clp->cl_lru); > >>>> INIT_LIST_HEAD(&clp->cl_revoked); > >>>>+ INIT_LIST_HEAD(&clp->cl_cs_list); > >>>> #ifdef CONFIG_NFSD_PNFS > >>>> INIT_LIST_HEAD(&clp->cl_lo_states); > >>>> #endif > >>>> INIT_LIST_HEAD(&clp->async_copies); > >>>> spin_lock_init(&clp->async_lock); > >>>> spin_lock_init(&clp->cl_lock); > >>>>+ spin_lock_init(&clp->cl_cs_lock); > >>>> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); > >>>> return clp; > >>>> err_no_hashtbl: > >>>>diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > >>>>index 4fc1fd639527..23996c6ca75e 100644 > >>>>--- a/fs/nfsd/nfsd.h > >>>>+++ b/fs/nfsd/nfsd.h > >>>>@@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); > >>>> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ > >>>> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ > >>>>+#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ > >>>> /* > >>>> * The following attributes are currently not supported by the NFSv4 server: > >>>>diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > >>>>index 95457cfd37fc..40e390abc842 100644 > >>>>--- a/fs/nfsd/state.h > >>>>+++ b/fs/nfsd/state.h > >>>>@@ -283,6 +283,35 @@ struct nfsd4_sessionid { > >>>> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ > >>>> /* > >>>>+ * CLIENT_ CLIENT_ CLIENT_ > >>>>+ * COURTESY EXPIRED RECONNECTED Meaning Where set > >>>>+ * ----------------------------------------------------------------------------- > >>>>+ * | false | false | false | Confirmed, active | Default | > >>>>+ * |---------------------------------------------------------------------------| > >>>>+ * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | > >>>>+ * | | | | Lease/lock/share | | > >>>>+ * | | | | reservation conflict | | > >>>>+ * | | | | can cause Courtesy | | > >>>>+ * | | | | client to be expired | | > >>>>+ * |---------------------------------------------------------------------------| > >>>>+ * | false | true | false | Courtesy client to be| nfs4_laundromat | > >>>>+ * | | | | expired by Laundromat| nfsd4_lm_lock_expired | > >>>>+ * | | | | due to conflict | nfsd4_discard_courtesy_clnt | > >>>>+ * | | | | | nfsd4_expire_courtesy_clnt | > >>>>+ * |---------------------------------------------------------------------------| > >>>>+ * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| > >>>>+ * | | | | reconnected, | | > >>>>+ * | | | | becoming active | | > >>>>+ * ----------------------------------------------------------------------------- > >By the way, where is a client returned to the normal (0) state? That > >has to happen at some point. > > For 4.1 courtesy client reconnects is detected in nfsd4_sequence, > nfsd4_bind_conn_to_session. Those are the places where NFSD54_CLIENT_RECONNECTED is set, which isn't the question I asked. > >Why are RECONNECTED clients discarded in so many cases? (E.g. whenever > >a bind_conn_to_session fails). > > find_in_sessionid_hashtbl: we discard the courtesy client when it > reconnects and there is error from nfsd4_get_session_locked. This > should be a rare condition so rather than reverting the client > state back to courtesy, it is simpler just to discard it. That may be a rare situation, but I don't believe the behavior of discarding the client in this case is correct. > nfsd4_create_session/find_confirmed_client: I think the only time > the courtesy client sends CREATE_SESSION, before sending the SEQUENCE > to reconnect after missing its leases, is when it wants to do clientid > trunking. This should be a rare condition so instead of dealing > with it we just do not allow it and discard the client for now. We can't wave away incorrect behavior with "but it's rare". Users with heavy and/or unusual workloads hit rare conditions. Clients may change their behavior over time. (E.g., trunking may become more common.) --b. > nfsd4_destroy_clientid/find_confirmed_client: instead of destroy > the courtesy client here we just let the laundromat destroy it > as if the client already expired. > > nfsd4_setclientid_confirm/find_confirmed_client: there should not > be any courtesy client found from nfsd4_setclientid_confirm, it > should be detected and discarded in nfsd4_setclientid. > > -Dai > > >>>These are mutually exclusive values, not bits that may set to 0 or 1, so > >>>the three boolean columns are confusing. I'd just structure the table > >>>like: > >>> > >>> client state meaning where set > >>> 0 Confirmed, active Default > >>> CLIENT_COURTESY Courtesy state.... nfs4_get_client_reaplist > >>> CLIENT_EXPIRED Courtesy client to be.. nfs4_laundromat > >>> > >>>etc. > >>will fix in v19. > >> > >>Thanks, > >>-Dai > >> > >>>--b. > >>> > >>>>+ */ > >>>>+ > >>>>+enum courtesy_client_state { > >>>>+ NFSD4_CLIENT_COURTESY = 1, > >>>>+ NFSD4_CLIENT_EXPIRED, > >>>>+ NFSD4_CLIENT_RECONNECTED, > >>>>+}; > >>>>+ > >>>>+/* > >>>> * struct nfs4_client - one per client. Clientids live here. > >>>> * > >>>> * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0) > >>>>@@ -385,6 +414,10 @@ struct nfs4_client { > >>>> struct list_head async_copies; /* list of async copies */ > >>>> spinlock_t async_lock; /* lock for async copies */ > >>>> atomic_t cl_cb_inflight; /* Outstanding callbacks */ > >>>>+ > >>>>+ enum courtesy_client_state cl_cs_client_state; > >>>>+ spinlock_t cl_cs_lock; > >>>>+ struct list_head cl_cs_list; > >>>> }; > >>>> /* struct nfs4_client_reset > >>>>-- > >>>>2.9.5
> On Mar 29, 2022, at 2:39 PM, J. Bruce Fields <bfields@fieldses.org> wrote: > > On Tue, Mar 29, 2022 at 11:19:51AM -0700, dai.ngo@oracle.com wrote: >> >> On 3/29/22 9:30 AM, J. Bruce Fields wrote: >>> On Tue, Mar 29, 2022 at 09:20:02AM -0700, dai.ngo@oracle.com wrote: >>>> On 3/29/22 8:47 AM, J. Bruce Fields wrote: >>>>> On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: >>>>>> Update nfs4_client to add: >>>>>> . cl_cs_client_state: courtesy client state >>>>>> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state >>>>>> . cl_cs_list: list used by laundromat to process courtesy clients >>>>>> >>>>>> Modify alloc_client to initialize these fields. >>>>>> >>>>>> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> >>>>>> --- >>>>>> fs/nfsd/nfs4state.c | 2 ++ >>>>>> fs/nfsd/nfsd.h | 1 + >>>>>> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ >>>>>> 3 files changed, 36 insertions(+) >>>>>> >>>>>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c >>>>>> index 234e852fcdfa..a65d59510681 100644 >>>>>> --- a/fs/nfsd/nfs4state.c >>>>>> +++ b/fs/nfsd/nfs4state.c >>>>>> @@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) >>>>>> INIT_LIST_HEAD(&clp->cl_delegations); >>>>>> INIT_LIST_HEAD(&clp->cl_lru); >>>>>> INIT_LIST_HEAD(&clp->cl_revoked); >>>>>> + INIT_LIST_HEAD(&clp->cl_cs_list); >>>>>> #ifdef CONFIG_NFSD_PNFS >>>>>> INIT_LIST_HEAD(&clp->cl_lo_states); >>>>>> #endif >>>>>> INIT_LIST_HEAD(&clp->async_copies); >>>>>> spin_lock_init(&clp->async_lock); >>>>>> spin_lock_init(&clp->cl_lock); >>>>>> + spin_lock_init(&clp->cl_cs_lock); >>>>>> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); >>>>>> return clp; >>>>>> err_no_hashtbl: >>>>>> diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h >>>>>> index 4fc1fd639527..23996c6ca75e 100644 >>>>>> --- a/fs/nfsd/nfsd.h >>>>>> +++ b/fs/nfsd/nfsd.h >>>>>> @@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); >>>>>> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ >>>>>> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ >>>>>> +#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ >>>>>> /* >>>>>> * The following attributes are currently not supported by the NFSv4 server: >>>>>> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h >>>>>> index 95457cfd37fc..40e390abc842 100644 >>>>>> --- a/fs/nfsd/state.h >>>>>> +++ b/fs/nfsd/state.h >>>>>> @@ -283,6 +283,35 @@ struct nfsd4_sessionid { >>>>>> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ >>>>>> /* >>>>>> + * CLIENT_ CLIENT_ CLIENT_ >>>>>> + * COURTESY EXPIRED RECONNECTED Meaning Where set >>>>>> + * ----------------------------------------------------------------------------- >>>>>> + * | false | false | false | Confirmed, active | Default | >>>>>> + * |---------------------------------------------------------------------------| >>>>>> + * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | >>>>>> + * | | | | Lease/lock/share | | >>>>>> + * | | | | reservation conflict | | >>>>>> + * | | | | can cause Courtesy | | >>>>>> + * | | | | client to be expired | | >>>>>> + * |---------------------------------------------------------------------------| >>>>>> + * | false | true | false | Courtesy client to be| nfs4_laundromat | >>>>>> + * | | | | expired by Laundromat| nfsd4_lm_lock_expired | >>>>>> + * | | | | due to conflict | nfsd4_discard_courtesy_clnt | >>>>>> + * | | | | | nfsd4_expire_courtesy_clnt | >>>>>> + * |---------------------------------------------------------------------------| >>>>>> + * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| >>>>>> + * | | | | reconnected, | | >>>>>> + * | | | | becoming active | | >>>>>> + * ----------------------------------------------------------------------------- >>> By the way, where is a client returned to the normal (0) state? That >>> has to happen at some point. >> >> For 4.1 courtesy client reconnects is detected in nfsd4_sequence, >> nfsd4_bind_conn_to_session. > > Those are the places where NFSD54_CLIENT_RECONNECTED is set, which isn't > the question I asked. "reconnected" simply means the client has gotten back in touch. The server then has to decide whether to allow the client to become active again or it needs to purge it. That decision is different for each operation and minor version. Look for "if (cl_cs_client_state == NFSD4_CLIENT_RECONNECTED)" for how those choices are made. >>> Why are RECONNECTED clients discarded in so many cases? (E.g. whenever >>> a bind_conn_to_session fails). >> >> find_in_sessionid_hashtbl: we discard the courtesy client when it >> reconnects and there is error from nfsd4_get_session_locked. This >> should be a rare condition so rather than reverting the client >> state back to courtesy, it is simpler just to discard it. > > That may be a rare situation, but I don't believe the behavior of > discarding the client in this case is correct. Can you explain this? It's a courtesy client... the server can decide it's expired at that point, can't it? IOW what breaks? >> nfsd4_create_session/find_confirmed_client: I think the only time >> the courtesy client sends CREATE_SESSION, before sending the SEQUENCE >> to reconnect after missing its leases, is when it wants to do clientid >> trunking. This should be a rare condition so instead of dealing >> with it we just do not allow it and discard the client for now. > > We can't wave away incorrect behavior with "but it's rare". Users with > heavy and/or unusual workloads hit rare conditions. Clients may change > their behavior over time. (E.g., trunking may become more common.) -- Chuck Lever
On Tue, Mar 29, 2022 at 07:32:57PM +0000, Chuck Lever III wrote: > > > > On Mar 29, 2022, at 2:39 PM, J. Bruce Fields <bfields@fieldses.org> wrote: > > > > On Tue, Mar 29, 2022 at 11:19:51AM -0700, dai.ngo@oracle.com wrote: > >> > >> On 3/29/22 9:30 AM, J. Bruce Fields wrote: > >>> On Tue, Mar 29, 2022 at 09:20:02AM -0700, dai.ngo@oracle.com wrote: > >>>> On 3/29/22 8:47 AM, J. Bruce Fields wrote: > >>>>> On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: > >>>>>> Update nfs4_client to add: > >>>>>> . cl_cs_client_state: courtesy client state > >>>>>> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state > >>>>>> . cl_cs_list: list used by laundromat to process courtesy clients > >>>>>> > >>>>>> Modify alloc_client to initialize these fields. > >>>>>> > >>>>>> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> > >>>>>> --- > >>>>>> fs/nfsd/nfs4state.c | 2 ++ > >>>>>> fs/nfsd/nfsd.h | 1 + > >>>>>> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ > >>>>>> 3 files changed, 36 insertions(+) > >>>>>> > >>>>>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > >>>>>> index 234e852fcdfa..a65d59510681 100644 > >>>>>> --- a/fs/nfsd/nfs4state.c > >>>>>> +++ b/fs/nfsd/nfs4state.c > >>>>>> @@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) > >>>>>> INIT_LIST_HEAD(&clp->cl_delegations); > >>>>>> INIT_LIST_HEAD(&clp->cl_lru); > >>>>>> INIT_LIST_HEAD(&clp->cl_revoked); > >>>>>> + INIT_LIST_HEAD(&clp->cl_cs_list); > >>>>>> #ifdef CONFIG_NFSD_PNFS > >>>>>> INIT_LIST_HEAD(&clp->cl_lo_states); > >>>>>> #endif > >>>>>> INIT_LIST_HEAD(&clp->async_copies); > >>>>>> spin_lock_init(&clp->async_lock); > >>>>>> spin_lock_init(&clp->cl_lock); > >>>>>> + spin_lock_init(&clp->cl_cs_lock); > >>>>>> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); > >>>>>> return clp; > >>>>>> err_no_hashtbl: > >>>>>> diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > >>>>>> index 4fc1fd639527..23996c6ca75e 100644 > >>>>>> --- a/fs/nfsd/nfsd.h > >>>>>> +++ b/fs/nfsd/nfsd.h > >>>>>> @@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); > >>>>>> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ > >>>>>> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ > >>>>>> +#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ > >>>>>> /* > >>>>>> * The following attributes are currently not supported by the NFSv4 server: > >>>>>> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > >>>>>> index 95457cfd37fc..40e390abc842 100644 > >>>>>> --- a/fs/nfsd/state.h > >>>>>> +++ b/fs/nfsd/state.h > >>>>>> @@ -283,6 +283,35 @@ struct nfsd4_sessionid { > >>>>>> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ > >>>>>> /* > >>>>>> + * CLIENT_ CLIENT_ CLIENT_ > >>>>>> + * COURTESY EXPIRED RECONNECTED Meaning Where set > >>>>>> + * ----------------------------------------------------------------------------- > >>>>>> + * | false | false | false | Confirmed, active | Default | > >>>>>> + * |---------------------------------------------------------------------------| > >>>>>> + * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | > >>>>>> + * | | | | Lease/lock/share | | > >>>>>> + * | | | | reservation conflict | | > >>>>>> + * | | | | can cause Courtesy | | > >>>>>> + * | | | | client to be expired | | > >>>>>> + * |---------------------------------------------------------------------------| > >>>>>> + * | false | true | false | Courtesy client to be| nfs4_laundromat | > >>>>>> + * | | | | expired by Laundromat| nfsd4_lm_lock_expired | > >>>>>> + * | | | | due to conflict | nfsd4_discard_courtesy_clnt | > >>>>>> + * | | | | | nfsd4_expire_courtesy_clnt | > >>>>>> + * |---------------------------------------------------------------------------| > >>>>>> + * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| > >>>>>> + * | | | | reconnected, | | > >>>>>> + * | | | | becoming active | | > >>>>>> + * ----------------------------------------------------------------------------- > >>> By the way, where is a client returned to the normal (0) state? That > >>> has to happen at some point. > >> > >> For 4.1 courtesy client reconnects is detected in nfsd4_sequence, > >> nfsd4_bind_conn_to_session. > > > > Those are the places where NFSD54_CLIENT_RECONNECTED is set, which isn't > > the question I asked. > > "reconnected" simply means the client has gotten back in touch. Again, my question was: when is cl_cs_client_state set back to 0? As far as I can tell, the answer is never. That means, even long after the client has reconnected, it's left in a weird state where it can be suddenly expired for all sorts of reasons. > The server then has to decide whether to allow the client to > become active again or it needs to purge it. That decision > is different for each operation and minor version. Look for > "if (cl_cs_client_state == NFSD4_CLIENT_RECONNECTED)" for how > those choices are made. > > > >>> Why are RECONNECTED clients discarded in so many cases? (E.g. whenever > >>> a bind_conn_to_session fails). > >> > >> find_in_sessionid_hashtbl: we discard the courtesy client when it > >> reconnects and there is error from nfsd4_get_session_locked. This > >> should be a rare condition so rather than reverting the client > >> state back to courtesy, it is simpler just to discard it. > > > > That may be a rare situation, but I don't believe the behavior of > > discarding the client in this case is correct. > > Can you explain this? It's a courtesy client... the server can > decide it's expired at that point, can't it? IOW what breaks? I'm not worried about courtesy clients, I'm worried about clients that were courtesy clients but have since succesfully renewed their state. Expiring them for a failed bind_conn_to_session isn't right. --b. > > > >> nfsd4_create_session/find_confirmed_client: I think the only time > >> the courtesy client sends CREATE_SESSION, before sending the SEQUENCE > >> to reconnect after missing its leases, is when it wants to do clientid > >> trunking. This should be a rare condition so instead of dealing > >> with it we just do not allow it and discard the client for now. > > > > We can't wave away incorrect behavior with "but it's rare". Users with > > heavy and/or unusual workloads hit rare conditions. Clients may change > > their behavior over time. (E.g., trunking may become more common.) > > > -- > Chuck Lever > >
> On Mar 29, 2022, at 3:49 PM, Bruce Fields <bfields@fieldses.org> wrote: > > On Tue, Mar 29, 2022 at 07:32:57PM +0000, Chuck Lever III wrote: >> >> >>> On Mar 29, 2022, at 2:39 PM, J. Bruce Fields <bfields@fieldses.org> wrote: >>> >>> On Tue, Mar 29, 2022 at 11:19:51AM -0700, dai.ngo@oracle.com wrote: >>>> >>>> On 3/29/22 9:30 AM, J. Bruce Fields wrote: >>>>> On Tue, Mar 29, 2022 at 09:20:02AM -0700, dai.ngo@oracle.com wrote: >>>>>> On 3/29/22 8:47 AM, J. Bruce Fields wrote: >>>>>>> On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: >>>>>>>> Update nfs4_client to add: >>>>>>>> . cl_cs_client_state: courtesy client state >>>>>>>> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state >>>>>>>> . cl_cs_list: list used by laundromat to process courtesy clients >>>>>>>> >>>>>>>> Modify alloc_client to initialize these fields. >>>>>>>> >>>>>>>> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> >>>>>>>> --- >>>>>>>> fs/nfsd/nfs4state.c | 2 ++ >>>>>>>> fs/nfsd/nfsd.h | 1 + >>>>>>>> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ >>>>>>>> 3 files changed, 36 insertions(+) >>>>>>>> >>>>>>>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c >>>>>>>> index 234e852fcdfa..a65d59510681 100644 >>>>>>>> --- a/fs/nfsd/nfs4state.c >>>>>>>> +++ b/fs/nfsd/nfs4state.c >>>>>>>> @@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) >>>>>>>> INIT_LIST_HEAD(&clp->cl_delegations); >>>>>>>> INIT_LIST_HEAD(&clp->cl_lru); >>>>>>>> INIT_LIST_HEAD(&clp->cl_revoked); >>>>>>>> + INIT_LIST_HEAD(&clp->cl_cs_list); >>>>>>>> #ifdef CONFIG_NFSD_PNFS >>>>>>>> INIT_LIST_HEAD(&clp->cl_lo_states); >>>>>>>> #endif >>>>>>>> INIT_LIST_HEAD(&clp->async_copies); >>>>>>>> spin_lock_init(&clp->async_lock); >>>>>>>> spin_lock_init(&clp->cl_lock); >>>>>>>> + spin_lock_init(&clp->cl_cs_lock); >>>>>>>> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); >>>>>>>> return clp; >>>>>>>> err_no_hashtbl: >>>>>>>> diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h >>>>>>>> index 4fc1fd639527..23996c6ca75e 100644 >>>>>>>> --- a/fs/nfsd/nfsd.h >>>>>>>> +++ b/fs/nfsd/nfsd.h >>>>>>>> @@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); >>>>>>>> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ >>>>>>>> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ >>>>>>>> +#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ >>>>>>>> /* >>>>>>>> * The following attributes are currently not supported by the NFSv4 server: >>>>>>>> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h >>>>>>>> index 95457cfd37fc..40e390abc842 100644 >>>>>>>> --- a/fs/nfsd/state.h >>>>>>>> +++ b/fs/nfsd/state.h >>>>>>>> @@ -283,6 +283,35 @@ struct nfsd4_sessionid { >>>>>>>> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ >>>>>>>> /* >>>>>>>> + * CLIENT_ CLIENT_ CLIENT_ >>>>>>>> + * COURTESY EXPIRED RECONNECTED Meaning Where set >>>>>>>> + * ----------------------------------------------------------------------------- >>>>>>>> + * | false | false | false | Confirmed, active | Default | >>>>>>>> + * |---------------------------------------------------------------------------| >>>>>>>> + * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | >>>>>>>> + * | | | | Lease/lock/share | | >>>>>>>> + * | | | | reservation conflict | | >>>>>>>> + * | | | | can cause Courtesy | | >>>>>>>> + * | | | | client to be expired | | >>>>>>>> + * |---------------------------------------------------------------------------| >>>>>>>> + * | false | true | false | Courtesy client to be| nfs4_laundromat | >>>>>>>> + * | | | | expired by Laundromat| nfsd4_lm_lock_expired | >>>>>>>> + * | | | | due to conflict | nfsd4_discard_courtesy_clnt | >>>>>>>> + * | | | | | nfsd4_expire_courtesy_clnt | >>>>>>>> + * |---------------------------------------------------------------------------| >>>>>>>> + * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| >>>>>>>> + * | | | | reconnected, | | >>>>>>>> + * | | | | becoming active | | >>>>>>>> + * ----------------------------------------------------------------------------- >>>>> By the way, where is a client returned to the normal (0) state? That >>>>> has to happen at some point. >>>> >>>> For 4.1 courtesy client reconnects is detected in nfsd4_sequence, >>>> nfsd4_bind_conn_to_session. >>> >>> Those are the places where NFSD54_CLIENT_RECONNECTED is set, which isn't >>> the question I asked. >> >> "reconnected" simply means the client has gotten back in touch. > > Again, my question was: when is cl_cs_client_state set back to 0? As > far as I can tell, the answer is never. That means, even long after the > client has reconnected, it's left in a weird state where it can be > suddenly expired for all sorts of reasons. Got it. Agreed, cl_cs_client_state should be reinitialized if a courtesy client is transitioned back to "active". Dai, would you add +enum courtesy_client_state { >>> NFSD4_CLIENT_ACTIVE = 0, + NFSD4_CLIENT_COURTESY, + NFSD4_CLIENT_EXPIRED, + NFSD4_CLIENT_RECONNECTED, +}; And set cl_cs_client_state to ACTIVE where the client is allowed to transition back to being active? >> The server then has to decide whether to allow the client to >> become active again or it needs to purge it. That decision >> is different for each operation and minor version. Look for >> "if (cl_cs_client_state == NFSD4_CLIENT_RECONNECTED)" for how >> those choices are made. >> >> >>>>> Why are RECONNECTED clients discarded in so many cases? (E.g. whenever >>>>> a bind_conn_to_session fails). >>>> >>>> find_in_sessionid_hashtbl: we discard the courtesy client when it >>>> reconnects and there is error from nfsd4_get_session_locked. This >>>> should be a rare condition so rather than reverting the client >>>> state back to courtesy, it is simpler just to discard it. >>> >>> That may be a rare situation, but I don't believe the behavior of >>> discarding the client in this case is correct. >> >> Can you explain this? It's a courtesy client... the server can >> decide it's expired at that point, can't it? IOW what breaks? > > I'm not worried about courtesy clients, I'm worried about clients that > were courtesy clients but have since succesfully renewed their state. > Expiring them for a failed bind_conn_to_session isn't right. -- Chuck Lever
On Tue, Mar 29, 2022 at 07:58:46PM +0000, Chuck Lever III wrote: > Got it. Agreed, cl_cs_client_state should be reinitialized if > a courtesy client is transitioned back to "active". > > Dai, would you add > > +enum courtesy_client_state { > >>> NFSD4_CLIENT_ACTIVE = 0, > + NFSD4_CLIENT_COURTESY, > + NFSD4_CLIENT_EXPIRED, > + NFSD4_CLIENT_RECONNECTED, > +}; > > And set cl_cs_client_state to ACTIVE where the client is > allowed to transition back to being active? I'm not clear then what the RECONNECTED->ACTIVE transition would be. My feeling is that the RECONNECTED state shouldn't exist, and that there should only be a transition of EXPIRED back to ACTIVE. --b.
> On Mar 29, 2022, at 4:01 PM, Bruce Fields <bfields@fieldses.org> wrote: > > On Tue, Mar 29, 2022 at 07:58:46PM +0000, Chuck Lever III wrote: >> Got it. Agreed, cl_cs_client_state should be reinitialized if >> a courtesy client is transitioned back to "active". >> >> Dai, would you add >> >> +enum courtesy_client_state { >>>>> NFSD4_CLIENT_ACTIVE = 0, >> + NFSD4_CLIENT_COURTESY, >> + NFSD4_CLIENT_EXPIRED, >> + NFSD4_CLIENT_RECONNECTED, >> +}; >> >> And set cl_cs_client_state to ACTIVE where the client is >> allowed to transition back to being active? > > I'm not clear then what the RECONNECTED->ACTIVE transition would be. > > My feeling is that the RECONNECTED state shouldn't exist, and that there > should only be a transition of EXPIRED back to ACTIVE. Audit the places that check for NFSD4_CLIENT_RECONNECTED. Some of them will expire a reconnected client, some will let it transition back to active. My impression from Dai was that the server cannot transition a courtesy client back to active in _every_ case. If you can demonstrate that in every case where RECONNECTED is found that a client should be transitioned to ACTIVE rather than discarded, then yes, we should get rid of RECONNECTED in favor of going from COURTESY -> ACTIVE. -- Chuck Lever
On 3/29/22 1:01 PM, Bruce Fields wrote: > On Tue, Mar 29, 2022 at 07:58:46PM +0000, Chuck Lever III wrote: >> Got it. Agreed, cl_cs_client_state should be reinitialized if >> a courtesy client is transitioned back to "active". >> >> Dai, would you add >> >> +enum courtesy_client_state { >>>>> NFSD4_CLIENT_ACTIVE = 0, >> + NFSD4_CLIENT_COURTESY, >> + NFSD4_CLIENT_EXPIRED, >> + NFSD4_CLIENT_RECONNECTED, >> +}; >> >> And set cl_cs_client_state to ACTIVE where the client is >> allowed to transition back to being active? fix in v19. > I'm not clear then what the RECONNECTED->ACTIVE transition would be. > > My feeling is that the RECONNECTED state shouldn't exist, and that there > should only be a transition of EXPIRED back to ACTIVE. For the client to be truly active we need to create the client record. We do not want to create the client record when we just detect that the client reconnects because not all the callers want the client to be active, we leave it for the callers to decide. Also some callers of nfsd4_courtesy_clnt_expired hold the nn->client_lock so we can create the client record there. Leaving the NFSD4_CLIENT_RECONNECTED state set does not really cause any functional problem since the RECONNECT state is meant to used temporary within the context of the same request. But I will reset the state back to NFSD4_CLIENT_ACTIVE for clarity. -Dai > > --b.
On 3/29/22 11:39 AM, J. Bruce Fields wrote: > On Tue, Mar 29, 2022 at 11:19:51AM -0700, dai.ngo@oracle.com wrote: >> On 3/29/22 9:30 AM, J. Bruce Fields wrote: >>> On Tue, Mar 29, 2022 at 09:20:02AM -0700, dai.ngo@oracle.com wrote: >>>> On 3/29/22 8:47 AM, J. Bruce Fields wrote: >>>>> On Thu, Mar 24, 2022 at 09:34:42PM -0700, Dai Ngo wrote: >>>>>> Update nfs4_client to add: >>>>>> . cl_cs_client_state: courtesy client state >>>>>> . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state >>>>>> . cl_cs_list: list used by laundromat to process courtesy clients >>>>>> >>>>>> Modify alloc_client to initialize these fields. >>>>>> >>>>>> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> >>>>>> --- >>>>>> fs/nfsd/nfs4state.c | 2 ++ >>>>>> fs/nfsd/nfsd.h | 1 + >>>>>> fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ >>>>>> 3 files changed, 36 insertions(+) >>>>>> >>>>>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c >>>>>> index 234e852fcdfa..a65d59510681 100644 >>>>>> --- a/fs/nfsd/nfs4state.c >>>>>> +++ b/fs/nfsd/nfs4state.c >>>>>> @@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) >>>>>> INIT_LIST_HEAD(&clp->cl_delegations); >>>>>> INIT_LIST_HEAD(&clp->cl_lru); >>>>>> INIT_LIST_HEAD(&clp->cl_revoked); >>>>>> + INIT_LIST_HEAD(&clp->cl_cs_list); >>>>>> #ifdef CONFIG_NFSD_PNFS >>>>>> INIT_LIST_HEAD(&clp->cl_lo_states); >>>>>> #endif >>>>>> INIT_LIST_HEAD(&clp->async_copies); >>>>>> spin_lock_init(&clp->async_lock); >>>>>> spin_lock_init(&clp->cl_lock); >>>>>> + spin_lock_init(&clp->cl_cs_lock); >>>>>> rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); >>>>>> return clp; >>>>>> err_no_hashtbl: >>>>>> diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h >>>>>> index 4fc1fd639527..23996c6ca75e 100644 >>>>>> --- a/fs/nfsd/nfsd.h >>>>>> +++ b/fs/nfsd/nfsd.h >>>>>> @@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); >>>>>> #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ >>>>>> #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ >>>>>> +#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ >>>>>> /* >>>>>> * The following attributes are currently not supported by the NFSv4 server: >>>>>> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h >>>>>> index 95457cfd37fc..40e390abc842 100644 >>>>>> --- a/fs/nfsd/state.h >>>>>> +++ b/fs/nfsd/state.h >>>>>> @@ -283,6 +283,35 @@ struct nfsd4_sessionid { >>>>>> #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ >>>>>> /* >>>>>> + * CLIENT_ CLIENT_ CLIENT_ >>>>>> + * COURTESY EXPIRED RECONNECTED Meaning Where set >>>>>> + * ----------------------------------------------------------------------------- >>>>>> + * | false | false | false | Confirmed, active | Default | >>>>>> + * |---------------------------------------------------------------------------| >>>>>> + * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | >>>>>> + * | | | | Lease/lock/share | | >>>>>> + * | | | | reservation conflict | | >>>>>> + * | | | | can cause Courtesy | | >>>>>> + * | | | | client to be expired | | >>>>>> + * |---------------------------------------------------------------------------| >>>>>> + * | false | true | false | Courtesy client to be| nfs4_laundromat | >>>>>> + * | | | | expired by Laundromat| nfsd4_lm_lock_expired | >>>>>> + * | | | | due to conflict | nfsd4_discard_courtesy_clnt | >>>>>> + * | | | | | nfsd4_expire_courtesy_clnt | >>>>>> + * |---------------------------------------------------------------------------| >>>>>> + * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| >>>>>> + * | | | | reconnected, | | >>>>>> + * | | | | becoming active | | >>>>>> + * ----------------------------------------------------------------------------- >>> By the way, where is a client returned to the normal (0) state? That >>> has to happen at some point. >> For 4.1 courtesy client reconnects is detected in nfsd4_sequence, >> nfsd4_bind_conn_to_session. > Those are the places where NFSD54_CLIENT_RECONNECTED is set, which isn't > the question I asked. >>> Why are RECONNECTED clients discarded in so many cases? (E.g. whenever >>> a bind_conn_to_session fails). >> find_in_sessionid_hashtbl: we discard the courtesy client when it >> reconnects and there is error from nfsd4_get_session_locked. This >> should be a rare condition so rather than reverting the client >> state back to courtesy, it is simpler just to discard it. > That may be a rare situation, but I don't believe the behavior of > discarding the client in this case is correct. > >> nfsd4_create_session/find_confirmed_client: I think the only time >> the courtesy client sends CREATE_SESSION, before sending the SEQUENCE >> to reconnect after missing its leases, is when it wants to do clientid >> trunking. This should be a rare condition so instead of dealing >> with it we just do not allow it and discard the client for now. > We can't wave away incorrect behavior with "but it's rare". Users with > heavy and/or unusual workloads hit rare conditions. Clients may change > their behavior over time. (E.g., trunking may become more common.) This does not prevent the courtesy client from doing trunking in all cases. It is only prevent the courtesy client from doing trunking without first reconnect to the server. I think this behavior is the same as if the server does not support courtesy client; the server can expire the courtesy anytime it wants. If the courtesy client reconnected successfully then by the time nfsd4_create_session/ find_confirmed_client is called the client already becomes active so the server will process the request normally. Also to handle cases when the courtesy client reconnects after it was in EXPIRED state, we want to force the client to recover its state starting with EXCHANGE_ID so we have to return BAD_SESSION on CREATE_SESSION request. -Dai
On Tue, Mar 29, 2022 at 02:45:28PM -0700, dai.ngo@oracle.com wrote: > This does not prevent the courtesy client from doing trunking in all > cases. It is only prevent the courtesy client from doing trunking without > first reconnect to the server. > > I think this behavior is the same as if the server does not support courtesy > client; the server can expire the courtesy anytime it wants. If the > courtesy client reconnected successfully then by the time nfsd4_create_session/ > find_confirmed_client is called the client already becomes active > so the server will process the request normally. I'm not sure what you mean here. All a client has to do to reconnect is succesfully renew its lease. That doesn't necessarily require calling CREATE_SESSION again. > Also to handle cases when the courtesy client reconnects after it was in > EXPIRED state, we want to force the client to recover its state starting > with EXCHANGE_ID so we have to return BAD_SESSION on CREATE_SESSION request. The client should not have to send EXCHANGE_ID. --b.
On 3/29/22 5:12 PM, J. Bruce Fields wrote: > On Tue, Mar 29, 2022 at 02:45:28PM -0700, dai.ngo@oracle.com wrote: >> This does not prevent the courtesy client from doing trunking in all >> cases. It is only prevent the courtesy client from doing trunking without >> first reconnect to the server. >> >> I think this behavior is the same as if the server does not support courtesy >> client; the server can expire the courtesy anytime it wants. If the >> courtesy client reconnected successfully then by the time nfsd4_create_session/ >> find_confirmed_client is called the client already becomes active >> so the server will process the request normally. > I'm not sure what you mean here. All a client has to do to reconnect is > succesfully renew its lease. For 4.1 the client renews its lease via the SEQUENCE, either stand-alone or in a compound. Once the SEQUENCE completes successfully then the subsequent CREATE_SESSION is processed normally. However, if the client did not send the SEQUENCE first then server returns BAD_SESSION for the CREATE_SESSION request. > That doesn't necessarily require calling > CREATE_SESSION again. > >> Also to handle cases when the courtesy client reconnects after it was in >> EXPIRED state, we want to force the client to recover its state starting >> with EXCHANGE_ID so we have to return BAD_SESSION on CREATE_SESSION request. > The client should not have to send EXCHANGE_ID. For 4.1 the expired courtesy client must send EXCHANGE_ID to reconnect to start new session. I don't see how the *expired* courtesy client can access the export again without sending the EXCHANGE_ID. Attached is the pcap that shows how the courtesy client recovers once it's in CLIENT_EXPIRED state. -Dai > > --b.
On Tue, Mar 29, 2022 at 06:17:29PM -0700, dai.ngo@oracle.com wrote: > > On 3/29/22 5:12 PM, J. Bruce Fields wrote: > >On Tue, Mar 29, 2022 at 02:45:28PM -0700, dai.ngo@oracle.com wrote: > >>This does not prevent the courtesy client from doing trunking in all > >>cases. It is only prevent the courtesy client from doing trunking without > >>first reconnect to the server. > >> > >>I think this behavior is the same as if the server does not support courtesy > >>client; the server can expire the courtesy anytime it wants. If the > >>courtesy client reconnected successfully then by the time nfsd4_create_session/ > >>find_confirmed_client is called the client already becomes active > >>so the server will process the request normally. > >I'm not sure what you mean here. All a client has to do to reconnect is > >succesfully renew its lease. > > For 4.1 the client renews its lease via the SEQUENCE, either stand-alone > or in a compound. Once the SEQUENCE completes successfully then the > subsequent CREATE_SESSION is processed normally. However, if the client > did not send the SEQUENCE first then server returns BAD_SESSION for the > CREATE_SESSION request. > > > That doesn't necessarily require calling > >CREATE_SESSION again. > > > >>Also to handle cases when the courtesy client reconnects after it was in > >>EXPIRED state, we want to force the client to recover its state starting > >>with EXCHANGE_ID so we have to return BAD_SESSION on CREATE_SESSION request. > >The client should not have to send EXCHANGE_ID. > > For 4.1 the expired courtesy client must send EXCHANGE_ID to reconnect > to start new session. I don't see how the *expired* courtesy client can > access the export again without sending the EXCHANGE_ID. Attached is the > pcap that shows how the courtesy client recovers once it's in > CLIENT_EXPIRED state. Oh, sorry, sure, we're talking about an actual expired client. That's fine. --b.
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 234e852fcdfa..a65d59510681 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -2009,12 +2009,14 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) INIT_LIST_HEAD(&clp->cl_delegations); INIT_LIST_HEAD(&clp->cl_lru); INIT_LIST_HEAD(&clp->cl_revoked); + INIT_LIST_HEAD(&clp->cl_cs_list); #ifdef CONFIG_NFSD_PNFS INIT_LIST_HEAD(&clp->cl_lo_states); #endif INIT_LIST_HEAD(&clp->async_copies); spin_lock_init(&clp->async_lock); spin_lock_init(&clp->cl_lock); + spin_lock_init(&clp->cl_cs_lock); rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); return clp; err_no_hashtbl: diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index 4fc1fd639527..23996c6ca75e 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -336,6 +336,7 @@ void nfsd_lockd_shutdown(void); #define COMPOUND_ERR_SLACK_SPACE 16 /* OP_SETATTR */ #define NFSD_LAUNDROMAT_MINTIMEOUT 1 /* seconds */ +#define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ /* * The following attributes are currently not supported by the NFSv4 server: diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index 95457cfd37fc..40e390abc842 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -283,6 +283,35 @@ struct nfsd4_sessionid { #define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */ /* + * CLIENT_ CLIENT_ CLIENT_ + * COURTESY EXPIRED RECONNECTED Meaning Where set + * ----------------------------------------------------------------------------- + * | false | false | false | Confirmed, active | Default | + * |---------------------------------------------------------------------------| + * | true | false | false | Courtesy state. | nfs4_get_client_reaplist | + * | | | | Lease/lock/share | | + * | | | | reservation conflict | | + * | | | | can cause Courtesy | | + * | | | | client to be expired | | + * |---------------------------------------------------------------------------| + * | false | true | false | Courtesy client to be| nfs4_laundromat | + * | | | | expired by Laundromat| nfsd4_lm_lock_expired | + * | | | | due to conflict | nfsd4_discard_courtesy_clnt | + * | | | | | nfsd4_expire_courtesy_clnt | + * |---------------------------------------------------------------------------| + * | false | false | true | Courtesy client | nfsd4_courtesy_clnt_expired| + * | | | | reconnected, | | + * | | | | becoming active | | + * ----------------------------------------------------------------------------- + */ + +enum courtesy_client_state { + NFSD4_CLIENT_COURTESY = 1, + NFSD4_CLIENT_EXPIRED, + NFSD4_CLIENT_RECONNECTED, +}; + +/* * struct nfs4_client - one per client. Clientids live here. * * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0) @@ -385,6 +414,10 @@ struct nfs4_client { struct list_head async_copies; /* list of async copies */ spinlock_t async_lock; /* lock for async copies */ atomic_t cl_cb_inflight; /* Outstanding callbacks */ + + enum courtesy_client_state cl_cs_client_state; + spinlock_t cl_cs_lock; + struct list_head cl_cs_list; }; /* struct nfs4_client_reset
Update nfs4_client to add: . cl_cs_client_state: courtesy client state . cl_cs_lock: spinlock to synchronize access to cl_cs_client_state . cl_cs_list: list used by laundromat to process courtesy clients Modify alloc_client to initialize these fields. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> --- fs/nfsd/nfs4state.c | 2 ++ fs/nfsd/nfsd.h | 1 + fs/nfsd/state.h | 33 +++++++++++++++++++++++++++++++++ 3 files changed, 36 insertions(+)