| Message ID | 1405696416-32585-5-git-send-email-jlayton@primarydata.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jul 18, 2014 at 11:13:30AM -0400, Jeff Layton wrote: > Ensure that the delegations cannot be found by the laundromat etc once > we add them to the various 'revoke' lists. So if I understand right, the big mutex protects all of this right now, so this is all just moving the unhashing under a finer-grained lock to prevent that in-between state being exposed after the big lock's dropped. Looks reasonable. --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/nfs4state.c | 37 +++++++++++++++++++++---------------- > 1 file changed, 21 insertions(+), 16 deletions(-) > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index 60ae21abce00..7c5233427c9b 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -650,13 +650,13 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp) > list_add(&dp->dl_perclnt, &dp->dl_stid.sc_client->cl_delegations); > } > > -/* Called under the state lock. */ > static void > -unhash_delegation(struct nfs4_delegation *dp) > +unhash_delegation_locked(struct nfs4_delegation *dp) > { > struct nfs4_file *fp = dp->dl_file; > > - spin_lock(&state_lock); > + lockdep_assert_held(&state_lock); > + > dp->dl_stid.sc_type = NFS4_CLOSED_DELEG_STID; > spin_lock(&fp->fi_lock); > list_del_init(&dp->dl_perclnt); > @@ -665,7 +665,6 @@ unhash_delegation(struct nfs4_delegation *dp) > spin_unlock(&fp->fi_lock); > if (fp) > nfs4_put_deleg_lease(fp); > - spin_unlock(&state_lock); > } > > static void destroy_revoked_delegation(struct nfs4_delegation *dp) > @@ -676,7 +675,9 @@ static void destroy_revoked_delegation(struct nfs4_delegation *dp) > > static void destroy_delegation(struct nfs4_delegation *dp) > { > - unhash_delegation(dp); > + spin_lock(&state_lock); > + unhash_delegation_locked(dp); > + spin_unlock(&state_lock); > nfs4_put_delegation(dp); > } > > @@ -685,11 +686,10 @@ static void revoke_delegation(struct nfs4_delegation *dp) > struct nfs4_client *clp = dp->dl_stid.sc_client; > > if (clp->cl_minorversion == 0) > - destroy_delegation(dp); > + destroy_revoked_delegation(dp); > else { > - unhash_delegation(dp); > dp->dl_stid.sc_type = NFS4_REVOKED_DELEG_STID; > - list_add(&dp->dl_recall_lru, &clp->cl_revoked); > + list_move(&dp->dl_recall_lru, &clp->cl_revoked); > } > } > > @@ -1447,15 +1447,16 @@ destroy_client(struct nfs4_client *clp) > spin_lock(&state_lock); > while (!list_empty(&clp->cl_delegations)) { > dp = list_entry(clp->cl_delegations.next, struct nfs4_delegation, dl_perclnt); > - list_del_init(&dp->dl_perclnt); > + unhash_delegation_locked(dp); > /* Ensure that deleg break won't try to requeue it */ > ++dp->dl_time; > - list_move(&dp->dl_recall_lru, &reaplist); > + list_add(&dp->dl_recall_lru, &reaplist); > } > spin_unlock(&state_lock); > while (!list_empty(&reaplist)) { > dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru); > - destroy_delegation(dp); > + list_del_init(&dp->dl_recall_lru); > + nfs4_put_delegation(dp); > } > list_splice_init(&clp->cl_revoked, &reaplist); > while (!list_empty(&reaplist)) { > @@ -3655,7 +3656,7 @@ nfs4_open_delegation(struct net *net, struct svc_fh *fh, > open->op_delegate_type = NFS4_OPEN_DELEGATE_READ; > return; > out_free: > - destroy_delegation(dp); > + nfs4_put_delegation(dp); > out_no_deleg: > open->op_delegate_type = NFS4_OPEN_DELEGATE_NONE; > if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS && > @@ -3894,7 +3895,8 @@ nfs4_laundromat(struct nfsd_net *nn) > new_timeo = min(new_timeo, t); > break; > } > - list_move(&dp->dl_recall_lru, &reaplist); > + unhash_delegation_locked(dp); > + list_add(&dp->dl_recall_lru, &reaplist); > } > spin_unlock(&state_lock); > list_for_each_safe(pos, next, &reaplist) { > @@ -5369,7 +5371,8 @@ static u64 nfsd_find_all_delegations(struct nfs4_client *clp, u64 max, > * don't monkey with it now that we are. > */ > ++dp->dl_time; > - list_move(&dp->dl_recall_lru, victims); > + unhash_delegation_locked(dp); > + list_add(&dp->dl_recall_lru, victims); > } > if (++count == max) > break; > @@ -5624,12 +5627,14 @@ nfs4_state_shutdown_net(struct net *net) > spin_lock(&state_lock); > list_for_each_safe(pos, next, &nn->del_recall_lru) { > dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru); > - list_move(&dp->dl_recall_lru, &reaplist); > + unhash_delegation_locked(dp); > + list_add(&dp->dl_recall_lru, &reaplist); > } > spin_unlock(&state_lock); > list_for_each_safe(pos, next, &reaplist) { > dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru); > - destroy_delegation(dp); > + list_del_init(&dp->dl_recall_lru); > + nfs4_put_delegation(dp); > } > > nfsd4_client_tracking_exit(net); > -- > 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 Fri, 18 Jul 2014 12:44:17 -0400 "J. Bruce Fields" <bfields@fieldses.org> wrote: > On Fri, Jul 18, 2014 at 11:13:30AM -0400, Jeff Layton wrote: > > Ensure that the delegations cannot be found by the laundromat etc once > > we add them to the various 'revoke' lists. > > So if I understand right, the big mutex protects all of this right now, > so this is all just moving the unhashing under a finer-grained lock to > prevent that in-between state being exposed after the big lock's > dropped. Looks reasonable. > > --b. > Yes, sorry -- I forgot the obligatory "this is not a problem until the client_mutex goes away" comment... > > > > 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/nfs4state.c | 37 +++++++++++++++++++++---------------- > > 1 file changed, 21 insertions(+), 16 deletions(-) > > > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > > index 60ae21abce00..7c5233427c9b 100644 > > --- a/fs/nfsd/nfs4state.c > > +++ b/fs/nfsd/nfs4state.c > > @@ -650,13 +650,13 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp) > > list_add(&dp->dl_perclnt, &dp->dl_stid.sc_client->cl_delegations); > > } > > > > -/* Called under the state lock. */ > > static void > > -unhash_delegation(struct nfs4_delegation *dp) > > +unhash_delegation_locked(struct nfs4_delegation *dp) > > { > > struct nfs4_file *fp = dp->dl_file; > > > > - spin_lock(&state_lock); > > + lockdep_assert_held(&state_lock); > > + > > dp->dl_stid.sc_type = NFS4_CLOSED_DELEG_STID; > > spin_lock(&fp->fi_lock); > > list_del_init(&dp->dl_perclnt); > > @@ -665,7 +665,6 @@ unhash_delegation(struct nfs4_delegation *dp) > > spin_unlock(&fp->fi_lock); > > if (fp) > > nfs4_put_deleg_lease(fp); > > - spin_unlock(&state_lock); > > } > > > > static void destroy_revoked_delegation(struct nfs4_delegation *dp) > > @@ -676,7 +675,9 @@ static void destroy_revoked_delegation(struct nfs4_delegation *dp) > > > > static void destroy_delegation(struct nfs4_delegation *dp) > > { > > - unhash_delegation(dp); > > + spin_lock(&state_lock); > > + unhash_delegation_locked(dp); > > + spin_unlock(&state_lock); > > nfs4_put_delegation(dp); > > } > > > > @@ -685,11 +686,10 @@ static void revoke_delegation(struct nfs4_delegation *dp) > > struct nfs4_client *clp = dp->dl_stid.sc_client; > > > > if (clp->cl_minorversion == 0) > > - destroy_delegation(dp); > > + destroy_revoked_delegation(dp); > > else { > > - unhash_delegation(dp); > > dp->dl_stid.sc_type = NFS4_REVOKED_DELEG_STID; > > - list_add(&dp->dl_recall_lru, &clp->cl_revoked); > > + list_move(&dp->dl_recall_lru, &clp->cl_revoked); > > } > > } > > > > @@ -1447,15 +1447,16 @@ destroy_client(struct nfs4_client *clp) > > spin_lock(&state_lock); > > while (!list_empty(&clp->cl_delegations)) { > > dp = list_entry(clp->cl_delegations.next, struct nfs4_delegation, dl_perclnt); > > - list_del_init(&dp->dl_perclnt); > > + unhash_delegation_locked(dp); > > /* Ensure that deleg break won't try to requeue it */ > > ++dp->dl_time; > > - list_move(&dp->dl_recall_lru, &reaplist); > > + list_add(&dp->dl_recall_lru, &reaplist); > > } > > spin_unlock(&state_lock); > > while (!list_empty(&reaplist)) { > > dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru); > > - destroy_delegation(dp); > > + list_del_init(&dp->dl_recall_lru); > > + nfs4_put_delegation(dp); > > } > > list_splice_init(&clp->cl_revoked, &reaplist); > > while (!list_empty(&reaplist)) { > > @@ -3655,7 +3656,7 @@ nfs4_open_delegation(struct net *net, struct svc_fh *fh, > > open->op_delegate_type = NFS4_OPEN_DELEGATE_READ; > > return; > > out_free: > > - destroy_delegation(dp); > > + nfs4_put_delegation(dp); > > out_no_deleg: > > open->op_delegate_type = NFS4_OPEN_DELEGATE_NONE; > > if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS && > > @@ -3894,7 +3895,8 @@ nfs4_laundromat(struct nfsd_net *nn) > > new_timeo = min(new_timeo, t); > > break; > > } > > - list_move(&dp->dl_recall_lru, &reaplist); > > + unhash_delegation_locked(dp); > > + list_add(&dp->dl_recall_lru, &reaplist); > > } > > spin_unlock(&state_lock); > > list_for_each_safe(pos, next, &reaplist) { > > @@ -5369,7 +5371,8 @@ static u64 nfsd_find_all_delegations(struct nfs4_client *clp, u64 max, > > * don't monkey with it now that we are. > > */ > > ++dp->dl_time; > > - list_move(&dp->dl_recall_lru, victims); > > + unhash_delegation_locked(dp); > > + list_add(&dp->dl_recall_lru, victims); > > } > > if (++count == max) > > break; > > @@ -5624,12 +5627,14 @@ nfs4_state_shutdown_net(struct net *net) > > spin_lock(&state_lock); > > list_for_each_safe(pos, next, &nn->del_recall_lru) { > > dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru); > > - list_move(&dp->dl_recall_lru, &reaplist); > > + unhash_delegation_locked(dp); > > + list_add(&dp->dl_recall_lru, &reaplist); > > } > > spin_unlock(&state_lock); > > list_for_each_safe(pos, next, &reaplist) { > > dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru); > > - destroy_delegation(dp); > > + list_del_init(&dp->dl_recall_lru); > > + nfs4_put_delegation(dp); > > } > > > > nfsd4_client_tracking_exit(net); > > -- > > 1.9.3 > >
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 60ae21abce00..7c5233427c9b 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -650,13 +650,13 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp) list_add(&dp->dl_perclnt, &dp->dl_stid.sc_client->cl_delegations); } -/* Called under the state lock. */ static void -unhash_delegation(struct nfs4_delegation *dp) +unhash_delegation_locked(struct nfs4_delegation *dp) { struct nfs4_file *fp = dp->dl_file; - spin_lock(&state_lock); + lockdep_assert_held(&state_lock); + dp->dl_stid.sc_type = NFS4_CLOSED_DELEG_STID; spin_lock(&fp->fi_lock); list_del_init(&dp->dl_perclnt); @@ -665,7 +665,6 @@ unhash_delegation(struct nfs4_delegation *dp) spin_unlock(&fp->fi_lock); if (fp) nfs4_put_deleg_lease(fp); - spin_unlock(&state_lock); } static void destroy_revoked_delegation(struct nfs4_delegation *dp) @@ -676,7 +675,9 @@ static void destroy_revoked_delegation(struct nfs4_delegation *dp) static void destroy_delegation(struct nfs4_delegation *dp) { - unhash_delegation(dp); + spin_lock(&state_lock); + unhash_delegation_locked(dp); + spin_unlock(&state_lock); nfs4_put_delegation(dp); } @@ -685,11 +686,10 @@ static void revoke_delegation(struct nfs4_delegation *dp) struct nfs4_client *clp = dp->dl_stid.sc_client; if (clp->cl_minorversion == 0) - destroy_delegation(dp); + destroy_revoked_delegation(dp); else { - unhash_delegation(dp); dp->dl_stid.sc_type = NFS4_REVOKED_DELEG_STID; - list_add(&dp->dl_recall_lru, &clp->cl_revoked); + list_move(&dp->dl_recall_lru, &clp->cl_revoked); } } @@ -1447,15 +1447,16 @@ destroy_client(struct nfs4_client *clp) spin_lock(&state_lock); while (!list_empty(&clp->cl_delegations)) { dp = list_entry(clp->cl_delegations.next, struct nfs4_delegation, dl_perclnt); - list_del_init(&dp->dl_perclnt); + unhash_delegation_locked(dp); /* Ensure that deleg break won't try to requeue it */ ++dp->dl_time; - list_move(&dp->dl_recall_lru, &reaplist); + list_add(&dp->dl_recall_lru, &reaplist); } spin_unlock(&state_lock); while (!list_empty(&reaplist)) { dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru); - destroy_delegation(dp); + list_del_init(&dp->dl_recall_lru); + nfs4_put_delegation(dp); } list_splice_init(&clp->cl_revoked, &reaplist); while (!list_empty(&reaplist)) { @@ -3655,7 +3656,7 @@ nfs4_open_delegation(struct net *net, struct svc_fh *fh, open->op_delegate_type = NFS4_OPEN_DELEGATE_READ; return; out_free: - destroy_delegation(dp); + nfs4_put_delegation(dp); out_no_deleg: open->op_delegate_type = NFS4_OPEN_DELEGATE_NONE; if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS && @@ -3894,7 +3895,8 @@ nfs4_laundromat(struct nfsd_net *nn) new_timeo = min(new_timeo, t); break; } - list_move(&dp->dl_recall_lru, &reaplist); + unhash_delegation_locked(dp); + list_add(&dp->dl_recall_lru, &reaplist); } spin_unlock(&state_lock); list_for_each_safe(pos, next, &reaplist) { @@ -5369,7 +5371,8 @@ static u64 nfsd_find_all_delegations(struct nfs4_client *clp, u64 max, * don't monkey with it now that we are. */ ++dp->dl_time; - list_move(&dp->dl_recall_lru, victims); + unhash_delegation_locked(dp); + list_add(&dp->dl_recall_lru, victims); } if (++count == max) break; @@ -5624,12 +5627,14 @@ nfs4_state_shutdown_net(struct net *net) spin_lock(&state_lock); list_for_each_safe(pos, next, &nn->del_recall_lru) { dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru); - list_move(&dp->dl_recall_lru, &reaplist); + unhash_delegation_locked(dp); + list_add(&dp->dl_recall_lru, &reaplist); } spin_unlock(&state_lock); list_for_each_safe(pos, next, &reaplist) { dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru); - destroy_delegation(dp); + list_del_init(&dp->dl_recall_lru); + nfs4_put_delegation(dp); } nfsd4_client_tracking_exit(net);