| Message ID | 1405521125-2303-3-git-send-email-jlayton@primarydata.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jul 16, 2014 at 10:31:57AM -0400, Jeff Layton wrote: > state_lock is a heavily contended global lock. We don't want to grab > that while simultaneously holding the inode->i_lock. > > Add a new per-nfs4_file lock that we can use to protect the > per-nfs4_file delegation list. Hold that while walking the list in the > break_deleg callback and queue the workqueue job for each one. > > The workqueue job can then take the state_lock and do the list > manipulations without the i_lock being held prior to starting the > rpc call. Looks fine. As a separate issue: does nfs4_state_shutdown net have the same problem as destroy_client? It seems like there should be a cp->dl_time++ there too. Though I'm not sure what the point of that del_recall_lru loop is at all. nfs4_state_destroy_net() destroys each client and its associated delegations. Maybe that function should just be nfs4_lock_state(); nfs4_client_tracking_exit(net); nfs4_state_destroy_net(net); WARN_ON(!list_empty(&nn->del_recall_lru); nfs4_unlock_state(); --b. > > Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> > Signed-off-by: Jeff Layton <jlayton@primarydata.com> > Reviewed-by: Christoph Hellwig <hch@lst.de> > --- > fs/nfsd/nfs4callback.c | 25 ++++++++++++++++++---- > fs/nfsd/nfs4state.c | 58 +++++++++++++++++++++++++++++++++----------------- > fs/nfsd/state.h | 4 +++- > 3 files changed, 62 insertions(+), 25 deletions(-) > > diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c > index 30a71cb46001..a88a93e09d69 100644 > --- a/fs/nfsd/nfs4callback.c > +++ b/fs/nfsd/nfs4callback.c > @@ -933,7 +933,7 @@ void nfsd4_shutdown_callback(struct nfs4_client *clp) > set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); > /* > * Note this won't actually result in a null callback; > - * instead, nfsd4_do_callback_rpc() will detect the killed > + * instead, nfsd4_run_cb_null() will detect the killed > * client, destroy the rpc client, and stop: > */ > do_probe_callback(clp); > @@ -1011,10 +1011,9 @@ static void nfsd4_process_cb_update(struct nfsd4_callback *cb) > run_nfsd4_cb(cb); > } > > -void > -nfsd4_do_callback_rpc(struct work_struct *w) > +static void > +nfsd4_run_callback_rpc(struct nfsd4_callback *cb) > { > - struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, cb_work); > struct nfs4_client *clp = cb->cb_clp; > struct rpc_clnt *clnt; > > @@ -1032,6 +1031,24 @@ nfsd4_do_callback_rpc(struct work_struct *w) > cb->cb_ops, cb); > } > > +void > +nfsd4_run_cb_null(struct work_struct *w) > +{ > + struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, > + cb_work); > + nfsd4_run_callback_rpc(cb); > +} > + > +void > +nfsd4_run_cb_recall(struct work_struct *w) > +{ > + struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, > + cb_work); > + > + nfsd4_prepare_cb_recall(cb->cb_op); > + nfsd4_run_callback_rpc(cb); > +} > + > void nfsd4_cb_recall(struct nfs4_delegation *dp) > { > struct nfsd4_callback *cb = &dp->dl_recall; > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index 56ea4f12803e..bdf8ac3393bd 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -254,6 +254,8 @@ static void nfsd4_free_file(struct nfs4_file *f) > static inline void > put_nfs4_file(struct nfs4_file *fi) > { > + might_lock(&state_lock); > + > if (atomic_dec_and_lock(&fi->fi_ref, &state_lock)) { > hlist_del(&fi->fi_hash); > spin_unlock(&state_lock); > @@ -554,6 +556,8 @@ static void block_delegations(struct knfsd_fh *fh) > u32 hash; > struct bloom_pair *bd = &blocked_delegations; > > + lockdep_assert_held(&state_lock); > + > hash = arch_fast_hash(&fh->fh_base, fh->fh_size, 0); > > __set_bit(hash&255, bd->set[bd->new]); > @@ -592,7 +596,7 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct sv > fh_copy_shallow(&dp->dl_fh, ¤t_fh->fh_handle); > dp->dl_time = 0; > atomic_set(&dp->dl_count, 1); > - INIT_WORK(&dp->dl_recall.cb_work, nfsd4_do_callback_rpc); > + INIT_WORK(&dp->dl_recall.cb_work, nfsd4_run_cb_recall); > return dp; > } > > @@ -640,7 +644,9 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp) > lockdep_assert_held(&state_lock); > > dp->dl_stid.sc_type = NFS4_DELEG_STID; > + spin_lock(&fp->fi_lock); > list_add(&dp->dl_perfile, &fp->fi_delegations); > + spin_unlock(&fp->fi_lock); > list_add(&dp->dl_perclnt, &dp->dl_stid.sc_client->cl_delegations); > } > > @@ -648,14 +654,18 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp) > static void > unhash_delegation(struct nfs4_delegation *dp) > { > + struct nfs4_file *fp = dp->dl_file; > + > spin_lock(&state_lock); > list_del_init(&dp->dl_perclnt); > - list_del_init(&dp->dl_perfile); > list_del_init(&dp->dl_recall_lru); > + spin_lock(&fp->fi_lock); > + list_del_init(&dp->dl_perfile); > + spin_unlock(&fp->fi_lock); > spin_unlock(&state_lock); > - if (dp->dl_file) { > - nfs4_put_deleg_lease(dp->dl_file); > - put_nfs4_file(dp->dl_file); > + if (fp) { > + nfs4_put_deleg_lease(fp); > + put_nfs4_file(fp); > dp->dl_file = NULL; > } > } > @@ -1677,7 +1687,7 @@ static struct nfs4_client *create_client(struct xdr_netobj name, > spin_unlock(&nn->client_lock); > return NULL; > } > - INIT_WORK(&clp->cl_cb_null.cb_work, nfsd4_do_callback_rpc); > + INIT_WORK(&clp->cl_cb_null.cb_work, nfsd4_run_cb_null); > clp->cl_time = get_seconds(); > clear_bit(0, &clp->cl_cb_slot_busy); > copy_verf(clp, verf); > @@ -3079,30 +3089,38 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type) > return ret; > } > > -static void nfsd_break_one_deleg(struct nfs4_delegation *dp) > +void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp) > { > struct nfs4_client *clp = dp->dl_stid.sc_client; > struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); > > - lockdep_assert_held(&state_lock); > - /* We're assuming the state code never drops its reference > - * without first removing the lease. Since we're in this lease > - * callback (and since the lease code is serialized by the kernel > - * lock) we know the server hasn't removed the lease yet, we know > - * it's safe to take a reference: */ > - atomic_inc(&dp->dl_count); > - > + /* > + * We can't do this in nfsd_break_deleg_cb because it is > + * already holding inode->i_lock > + */ > + spin_lock(&state_lock); > + block_delegations(&dp->dl_fh); > /* > * If the dl_time != 0, then we know that it has already been > * queued for a lease break. Don't queue it again. > */ > if (dp->dl_time == 0) { > - list_add_tail(&dp->dl_recall_lru, &nn->del_recall_lru); > dp->dl_time = get_seconds(); > + list_add_tail(&dp->dl_recall_lru, &nn->del_recall_lru); > } > + spin_unlock(&state_lock); > +} > > - block_delegations(&dp->dl_fh); > - > +static void nfsd_break_one_deleg(struct nfs4_delegation *dp) > +{ > + /* > + * We're assuming the state code never drops its reference > + * without first removing the lease. Since we're in this lease > + * callback (and since the lease code is serialized by the kernel > + * lock) we know the server hasn't removed the lease yet, we know > + * it's safe to take a reference. > + */ > + atomic_inc(&dp->dl_count); > nfsd4_cb_recall(dp); > } > > @@ -3127,11 +3145,11 @@ static void nfsd_break_deleg_cb(struct file_lock *fl) > */ > fl->fl_break_time = 0; > > - spin_lock(&state_lock); > fp->fi_had_conflict = true; > + spin_lock(&fp->fi_lock); > list_for_each_entry(dp, &fp->fi_delegations, dl_perfile) > nfsd_break_one_deleg(dp); > - spin_unlock(&state_lock); > + spin_unlock(&fp->fi_lock); > } > > static > diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > index 20857142773f..81b7522e3f67 100644 > --- a/fs/nfsd/state.h > +++ b/fs/nfsd/state.h > @@ -436,7 +436,8 @@ extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(const char *recdir, > extern __be32 nfs4_check_open_reclaim(clientid_t *clid, > struct nfsd4_compound_state *cstate, struct nfsd_net *nn); > extern int set_callback_cred(void); > -void nfsd4_do_callback_rpc(struct work_struct *w); > +void nfsd4_run_cb_null(struct work_struct *w); > +void nfsd4_run_cb_recall(struct work_struct *w); > extern void nfsd4_probe_callback(struct nfs4_client *clp); > extern void nfsd4_probe_callback_sync(struct nfs4_client *clp); > extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *); > @@ -444,6 +445,7 @@ extern void nfsd4_cb_recall(struct nfs4_delegation *dp); > extern int nfsd4_create_callback_queue(void); > extern void nfsd4_destroy_callback_queue(void); > extern void nfsd4_shutdown_callback(struct nfs4_client *); > +extern void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp); > extern void nfs4_put_delegation(struct nfs4_delegation *dp); > extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(const char *name, > struct nfsd_net *nn); > -- > 1.9.3 > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, 16 Jul 2014 21:34:41 -0400 "J. Bruce Fields" <bfields@fieldses.org> wrote: > On Wed, Jul 16, 2014 at 10:31:57AM -0400, Jeff Layton wrote: > > state_lock is a heavily contended global lock. We don't want to grab > > that while simultaneously holding the inode->i_lock. > > > > Add a new per-nfs4_file lock that we can use to protect the > > per-nfs4_file delegation list. Hold that while walking the list in the > > break_deleg callback and queue the workqueue job for each one. > > > > The workqueue job can then take the state_lock and do the list > > manipulations without the i_lock being held prior to starting the > > rpc call. > > Looks fine. > > As a separate issue: does nfs4_state_shutdown net have the same problem > as destroy_client? It seems like there should be a cp->dl_time++ there > too. > I had looked at that before and convinced myself that it wasn't needed, but now I can't recall why. I think you're correct though -- we ought to bump it there too. It certainly won't hurt to do so and it might prevent the same race there. > Though I'm not sure what the point of that del_recall_lru loop is at > all. nfs4_state_destroy_net() destroys each client and its associated > delegations. Maybe that function should just be > > nfs4_lock_state(); > nfs4_client_tracking_exit(net); > nfs4_state_destroy_net(net); > WARN_ON(!list_empty(&nn->del_recall_lru); > nfs4_unlock_state(); > > --b. > Yeah, it is odd. I end up relying on that for the "recall_delegations" fault injector in a later patch in the series, so I'd probably prefer to leave it as-is for now. We should be able to get rid of it eventually though. > > > > Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> > > Signed-off-by: Jeff Layton <jlayton@primarydata.com> > > Reviewed-by: Christoph Hellwig <hch@lst.de> > > --- > > fs/nfsd/nfs4callback.c | 25 ++++++++++++++++++---- > > fs/nfsd/nfs4state.c | 58 > > +++++++++++++++++++++++++++++++++----------------- > > fs/nfsd/state.h | 4 +++- 3 files changed, 62 insertions(+), > > 25 deletions(-) > > > > diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c > > index 30a71cb46001..a88a93e09d69 100644 > > --- a/fs/nfsd/nfs4callback.c > > +++ b/fs/nfsd/nfs4callback.c > > @@ -933,7 +933,7 @@ void nfsd4_shutdown_callback(struct nfs4_client > > *clp) set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); > > /* > > * Note this won't actually result in a null callback; > > - * instead, nfsd4_do_callback_rpc() will detect the killed > > + * instead, nfsd4_run_cb_null() will detect the killed > > * client, destroy the rpc client, and stop: > > */ > > do_probe_callback(clp); > > @@ -1011,10 +1011,9 @@ static void nfsd4_process_cb_update(struct > > nfsd4_callback *cb) run_nfsd4_cb(cb); > > } > > > > -void > > -nfsd4_do_callback_rpc(struct work_struct *w) > > +static void > > +nfsd4_run_callback_rpc(struct nfsd4_callback *cb) > > { > > - struct nfsd4_callback *cb = container_of(w, struct > > nfsd4_callback, cb_work); struct nfs4_client *clp = cb->cb_clp; > > struct rpc_clnt *clnt; > > > > @@ -1032,6 +1031,24 @@ nfsd4_do_callback_rpc(struct work_struct *w) > > cb->cb_ops, cb); > > } > > > > +void > > +nfsd4_run_cb_null(struct work_struct *w) > > +{ > > + struct nfsd4_callback *cb = container_of(w, struct > > nfsd4_callback, > > + cb_work); > > + nfsd4_run_callback_rpc(cb); > > +} > > + > > +void > > +nfsd4_run_cb_recall(struct work_struct *w) > > +{ > > + struct nfsd4_callback *cb = container_of(w, struct > > nfsd4_callback, > > + cb_work); > > + > > + nfsd4_prepare_cb_recall(cb->cb_op); > > + nfsd4_run_callback_rpc(cb); > > +} > > + > > void nfsd4_cb_recall(struct nfs4_delegation *dp) > > { > > struct nfsd4_callback *cb = &dp->dl_recall; > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > > index 56ea4f12803e..bdf8ac3393bd 100644 > > --- a/fs/nfsd/nfs4state.c > > +++ b/fs/nfsd/nfs4state.c > > @@ -254,6 +254,8 @@ static void nfsd4_free_file(struct nfs4_file *f) > > static inline void > > put_nfs4_file(struct nfs4_file *fi) > > { > > + might_lock(&state_lock); > > + > > if (atomic_dec_and_lock(&fi->fi_ref, &state_lock)) { > > hlist_del(&fi->fi_hash); > > spin_unlock(&state_lock); > > @@ -554,6 +556,8 @@ static void block_delegations(struct knfsd_fh > > *fh) u32 hash; > > struct bloom_pair *bd = &blocked_delegations; > > > > + lockdep_assert_held(&state_lock); > > + > > hash = arch_fast_hash(&fh->fh_base, fh->fh_size, 0); > > > > __set_bit(hash&255, bd->set[bd->new]); > > @@ -592,7 +596,7 @@ alloc_init_deleg(struct nfs4_client *clp, > > struct nfs4_ol_stateid *stp, struct sv fh_copy_shallow(&dp->dl_fh, > > ¤t_fh->fh_handle); dp->dl_time = 0; > > atomic_set(&dp->dl_count, 1); > > - INIT_WORK(&dp->dl_recall.cb_work, nfsd4_do_callback_rpc); > > + INIT_WORK(&dp->dl_recall.cb_work, nfsd4_run_cb_recall); > > return dp; > > } > > > > @@ -640,7 +644,9 @@ hash_delegation_locked(struct nfs4_delegation > > *dp, struct nfs4_file *fp) lockdep_assert_held(&state_lock); > > > > dp->dl_stid.sc_type = NFS4_DELEG_STID; > > + spin_lock(&fp->fi_lock); > > list_add(&dp->dl_perfile, &fp->fi_delegations); > > + spin_unlock(&fp->fi_lock); > > list_add(&dp->dl_perclnt, > > &dp->dl_stid.sc_client->cl_delegations); } > > > > @@ -648,14 +654,18 @@ hash_delegation_locked(struct nfs4_delegation > > *dp, struct nfs4_file *fp) static void > > unhash_delegation(struct nfs4_delegation *dp) > > { > > + struct nfs4_file *fp = dp->dl_file; > > + > > spin_lock(&state_lock); > > list_del_init(&dp->dl_perclnt); > > - list_del_init(&dp->dl_perfile); > > list_del_init(&dp->dl_recall_lru); > > + spin_lock(&fp->fi_lock); > > + list_del_init(&dp->dl_perfile); > > + spin_unlock(&fp->fi_lock); > > spin_unlock(&state_lock); > > - if (dp->dl_file) { > > - nfs4_put_deleg_lease(dp->dl_file); > > - put_nfs4_file(dp->dl_file); > > + if (fp) { > > + nfs4_put_deleg_lease(fp); > > + put_nfs4_file(fp); > > dp->dl_file = NULL; > > } > > } > > @@ -1677,7 +1687,7 @@ static struct nfs4_client > > *create_client(struct xdr_netobj name, > > spin_unlock(&nn->client_lock); return NULL; > > } > > - INIT_WORK(&clp->cl_cb_null.cb_work, nfsd4_do_callback_rpc); > > + INIT_WORK(&clp->cl_cb_null.cb_work, nfsd4_run_cb_null); > > clp->cl_time = get_seconds(); > > clear_bit(0, &clp->cl_cb_slot_busy); > > copy_verf(clp, verf); > > @@ -3079,30 +3089,38 @@ nfs4_share_conflict(struct svc_fh > > *current_fh, unsigned int deny_type) return ret; > > } > > > > -static void nfsd_break_one_deleg(struct nfs4_delegation *dp) > > +void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp) > > { > > struct nfs4_client *clp = dp->dl_stid.sc_client; > > struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); > > > > - lockdep_assert_held(&state_lock); > > - /* We're assuming the state code never drops its reference > > - * without first removing the lease. Since we're in this > > lease > > - * callback (and since the lease code is serialized by the > > kernel > > - * lock) we know the server hasn't removed the lease yet, > > we know > > - * it's safe to take a reference: */ > > - atomic_inc(&dp->dl_count); > > - > > + /* > > + * We can't do this in nfsd_break_deleg_cb because it is > > + * already holding inode->i_lock > > + */ > > + spin_lock(&state_lock); > > + block_delegations(&dp->dl_fh); > > /* > > * If the dl_time != 0, then we know that it has already > > been > > * queued for a lease break. Don't queue it again. > > */ > > if (dp->dl_time == 0) { > > - list_add_tail(&dp->dl_recall_lru, > > &nn->del_recall_lru); dp->dl_time = get_seconds(); > > + list_add_tail(&dp->dl_recall_lru, > > &nn->del_recall_lru); } > > + spin_unlock(&state_lock); > > +} > > > > - block_delegations(&dp->dl_fh); > > - > > +static void nfsd_break_one_deleg(struct nfs4_delegation *dp) > > +{ > > + /* > > + * We're assuming the state code never drops its reference > > + * without first removing the lease. Since we're in this > > lease > > + * callback (and since the lease code is serialized by the > > kernel > > + * lock) we know the server hasn't removed the lease yet, > > we know > > + * it's safe to take a reference. > > + */ > > + atomic_inc(&dp->dl_count); > > nfsd4_cb_recall(dp); > > } > > > > @@ -3127,11 +3145,11 @@ static void nfsd_break_deleg_cb(struct > > file_lock *fl) */ > > fl->fl_break_time = 0; > > > > - spin_lock(&state_lock); > > fp->fi_had_conflict = true; > > + spin_lock(&fp->fi_lock); > > list_for_each_entry(dp, &fp->fi_delegations, dl_perfile) > > nfsd_break_one_deleg(dp); > > - spin_unlock(&state_lock); > > + spin_unlock(&fp->fi_lock); > > } > > > > static > > diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > > index 20857142773f..81b7522e3f67 100644 > > --- a/fs/nfsd/state.h > > +++ b/fs/nfsd/state.h > > @@ -436,7 +436,8 @@ extern struct nfs4_client_reclaim > > *nfsd4_find_reclaim_client(const char *recdir, extern __be32 > > nfs4_check_open_reclaim(clientid_t *clid, struct > > nfsd4_compound_state *cstate, struct nfsd_net *nn); extern int > > set_callback_cred(void); -void nfsd4_do_callback_rpc(struct > > work_struct *w); +void nfsd4_run_cb_null(struct work_struct *w); > > +void nfsd4_run_cb_recall(struct work_struct *w); > > extern void nfsd4_probe_callback(struct nfs4_client *clp); > > extern void nfsd4_probe_callback_sync(struct nfs4_client *clp); > > extern void nfsd4_change_callback(struct nfs4_client *clp, struct > > nfs4_cb_conn *); @@ -444,6 +445,7 @@ extern void > > nfsd4_cb_recall(struct nfs4_delegation *dp); extern int > > nfsd4_create_callback_queue(void); extern void > > nfsd4_destroy_callback_queue(void); extern void > > nfsd4_shutdown_callback(struct nfs4_client *); +extern void > > nfsd4_prepare_cb_recall(struct nfs4_delegation *dp); extern void > > nfs4_put_delegation(struct nfs4_delegation *dp); extern struct > > nfs4_client_reclaim *nfs4_client_to_reclaim(const char *name, > > struct nfsd_net *nn); -- > > 1.9.3 > >
diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c index 30a71cb46001..a88a93e09d69 100644 --- a/fs/nfsd/nfs4callback.c +++ b/fs/nfsd/nfs4callback.c @@ -933,7 +933,7 @@ void nfsd4_shutdown_callback(struct nfs4_client *clp) set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); /* * Note this won't actually result in a null callback; - * instead, nfsd4_do_callback_rpc() will detect the killed + * instead, nfsd4_run_cb_null() will detect the killed * client, destroy the rpc client, and stop: */ do_probe_callback(clp); @@ -1011,10 +1011,9 @@ static void nfsd4_process_cb_update(struct nfsd4_callback *cb) run_nfsd4_cb(cb); } -void -nfsd4_do_callback_rpc(struct work_struct *w) +static void +nfsd4_run_callback_rpc(struct nfsd4_callback *cb) { - struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, cb_work); struct nfs4_client *clp = cb->cb_clp; struct rpc_clnt *clnt; @@ -1032,6 +1031,24 @@ nfsd4_do_callback_rpc(struct work_struct *w) cb->cb_ops, cb); } +void +nfsd4_run_cb_null(struct work_struct *w) +{ + struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, + cb_work); + nfsd4_run_callback_rpc(cb); +} + +void +nfsd4_run_cb_recall(struct work_struct *w) +{ + struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, + cb_work); + + nfsd4_prepare_cb_recall(cb->cb_op); + nfsd4_run_callback_rpc(cb); +} + void nfsd4_cb_recall(struct nfs4_delegation *dp) { struct nfsd4_callback *cb = &dp->dl_recall; diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 56ea4f12803e..bdf8ac3393bd 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -254,6 +254,8 @@ static void nfsd4_free_file(struct nfs4_file *f) static inline void put_nfs4_file(struct nfs4_file *fi) { + might_lock(&state_lock); + if (atomic_dec_and_lock(&fi->fi_ref, &state_lock)) { hlist_del(&fi->fi_hash); spin_unlock(&state_lock); @@ -554,6 +556,8 @@ static void block_delegations(struct knfsd_fh *fh) u32 hash; struct bloom_pair *bd = &blocked_delegations; + lockdep_assert_held(&state_lock); + hash = arch_fast_hash(&fh->fh_base, fh->fh_size, 0); __set_bit(hash&255, bd->set[bd->new]); @@ -592,7 +596,7 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct sv fh_copy_shallow(&dp->dl_fh, ¤t_fh->fh_handle); dp->dl_time = 0; atomic_set(&dp->dl_count, 1); - INIT_WORK(&dp->dl_recall.cb_work, nfsd4_do_callback_rpc); + INIT_WORK(&dp->dl_recall.cb_work, nfsd4_run_cb_recall); return dp; } @@ -640,7 +644,9 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp) lockdep_assert_held(&state_lock); dp->dl_stid.sc_type = NFS4_DELEG_STID; + spin_lock(&fp->fi_lock); list_add(&dp->dl_perfile, &fp->fi_delegations); + spin_unlock(&fp->fi_lock); list_add(&dp->dl_perclnt, &dp->dl_stid.sc_client->cl_delegations); } @@ -648,14 +654,18 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp) static void unhash_delegation(struct nfs4_delegation *dp) { + struct nfs4_file *fp = dp->dl_file; + spin_lock(&state_lock); list_del_init(&dp->dl_perclnt); - list_del_init(&dp->dl_perfile); list_del_init(&dp->dl_recall_lru); + spin_lock(&fp->fi_lock); + list_del_init(&dp->dl_perfile); + spin_unlock(&fp->fi_lock); spin_unlock(&state_lock); - if (dp->dl_file) { - nfs4_put_deleg_lease(dp->dl_file); - put_nfs4_file(dp->dl_file); + if (fp) { + nfs4_put_deleg_lease(fp); + put_nfs4_file(fp); dp->dl_file = NULL; } } @@ -1677,7 +1687,7 @@ static struct nfs4_client *create_client(struct xdr_netobj name, spin_unlock(&nn->client_lock); return NULL; } - INIT_WORK(&clp->cl_cb_null.cb_work, nfsd4_do_callback_rpc); + INIT_WORK(&clp->cl_cb_null.cb_work, nfsd4_run_cb_null); clp->cl_time = get_seconds(); clear_bit(0, &clp->cl_cb_slot_busy); copy_verf(clp, verf); @@ -3079,30 +3089,38 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type) return ret; } -static void nfsd_break_one_deleg(struct nfs4_delegation *dp) +void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp) { struct nfs4_client *clp = dp->dl_stid.sc_client; struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); - lockdep_assert_held(&state_lock); - /* We're assuming the state code never drops its reference - * without first removing the lease. Since we're in this lease - * callback (and since the lease code is serialized by the kernel - * lock) we know the server hasn't removed the lease yet, we know - * it's safe to take a reference: */ - atomic_inc(&dp->dl_count); - + /* + * We can't do this in nfsd_break_deleg_cb because it is + * already holding inode->i_lock + */ + spin_lock(&state_lock); + block_delegations(&dp->dl_fh); /* * If the dl_time != 0, then we know that it has already been * queued for a lease break. Don't queue it again. */ if (dp->dl_time == 0) { - list_add_tail(&dp->dl_recall_lru, &nn->del_recall_lru); dp->dl_time = get_seconds(); + list_add_tail(&dp->dl_recall_lru, &nn->del_recall_lru); } + spin_unlock(&state_lock); +} - block_delegations(&dp->dl_fh); - +static void nfsd_break_one_deleg(struct nfs4_delegation *dp) +{ + /* + * We're assuming the state code never drops its reference + * without first removing the lease. Since we're in this lease + * callback (and since the lease code is serialized by the kernel + * lock) we know the server hasn't removed the lease yet, we know + * it's safe to take a reference. + */ + atomic_inc(&dp->dl_count); nfsd4_cb_recall(dp); } @@ -3127,11 +3145,11 @@ static void nfsd_break_deleg_cb(struct file_lock *fl) */ fl->fl_break_time = 0; - spin_lock(&state_lock); fp->fi_had_conflict = true; + spin_lock(&fp->fi_lock); list_for_each_entry(dp, &fp->fi_delegations, dl_perfile) nfsd_break_one_deleg(dp); - spin_unlock(&state_lock); + spin_unlock(&fp->fi_lock); } static diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index 20857142773f..81b7522e3f67 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -436,7 +436,8 @@ extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(const char *recdir, extern __be32 nfs4_check_open_reclaim(clientid_t *clid, struct nfsd4_compound_state *cstate, struct nfsd_net *nn); extern int set_callback_cred(void); -void nfsd4_do_callback_rpc(struct work_struct *w); +void nfsd4_run_cb_null(struct work_struct *w); +void nfsd4_run_cb_recall(struct work_struct *w); extern void nfsd4_probe_callback(struct nfs4_client *clp); extern void nfsd4_probe_callback_sync(struct nfs4_client *clp); extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *); @@ -444,6 +445,7 @@ extern void nfsd4_cb_recall(struct nfs4_delegation *dp); extern int nfsd4_create_callback_queue(void); extern void nfsd4_destroy_callback_queue(void); extern void nfsd4_shutdown_callback(struct nfs4_client *); +extern void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp); extern void nfs4_put_delegation(struct nfs4_delegation *dp); extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(const char *name, struct nfsd_net *nn);