diff options
| -rw-r--r-- | fs/nfs/delegation.c | 7 | ||||
| -rw-r--r-- | fs/nfs/delegation.h | 1 | ||||
| -rw-r--r-- | fs/nfs/nfs4proc.c | 80 |
3 files changed, 60 insertions, 28 deletions
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index cc563cfa694..e0cb4ee3b23 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -140,13 +140,17 @@ static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfs if (delegation == NULL) goto nomatch; + spin_lock(&delegation->lock); if (stateid != NULL && memcmp(delegation->stateid.data, stateid->data, sizeof(delegation->stateid.data)) != 0) - goto nomatch; + goto nomatch_unlock; list_del_rcu(&delegation->super_list); nfsi->delegation_state = 0; rcu_assign_pointer(nfsi->delegation, NULL); + spin_unlock(&delegation->lock); return delegation; +nomatch_unlock: + spin_unlock(&delegation->lock); nomatch: return NULL; } @@ -172,6 +176,7 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct delegation->change_attr = nfsi->change_attr; delegation->cred = get_rpccred(cred); delegation->inode = inode; + spin_lock_init(&delegation->lock); spin_lock(&clp->cl_lock); if (rcu_dereference(nfsi->delegation) != NULL) { diff --git a/fs/nfs/delegation.h b/fs/nfs/delegation.h index f1c5e2a5d88..8299c6220e9 100644 --- a/fs/nfs/delegation.h +++ b/fs/nfs/delegation.h @@ -22,6 +22,7 @@ struct nfs_delegation { long flags; loff_t maxsize; __u64 change_attr; + spinlock_t lock; struct rcu_head rcu; }; diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 83e700a2b0c..254cbff103f 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -388,9 +388,8 @@ static void nfs_set_open_stateid(struct nfs4_state *state, nfs4_stateid *stateid write_sequnlock(&state->seqlock); } -static void update_open_stateid(struct nfs4_state *state, nfs4_stateid *open_stateid, nfs4_stateid *deleg_stateid, int open_flags) +static void __update_open_stateid(struct nfs4_state *state, nfs4_stateid *open_stateid, const nfs4_stateid *deleg_stateid, int open_flags) { - open_flags &= (FMODE_READ|FMODE_WRITE); /* * Protect the call to nfs4_state_set_mode_locked and * serialise the stateid update @@ -408,6 +407,45 @@ static void update_open_stateid(struct nfs4_state *state, nfs4_stateid *open_sta spin_unlock(&state->owner->so_lock); } +static int update_open_stateid(struct nfs4_state *state, nfs4_stateid *open_stateid, nfs4_stateid *delegation, int open_flags) +{ + struct nfs_inode *nfsi = NFS_I(state->inode); + struct nfs_delegation *deleg_cur; + int ret = 0; + + open_flags &= (FMODE_READ|FMODE_WRITE); + + rcu_read_lock(); + deleg_cur = rcu_dereference(nfsi->delegation); + if (deleg_cur == NULL) + goto no_delegation; + + spin_lock(&deleg_cur->lock); + if (nfsi->delegation != deleg_cur || + (deleg_cur->type & open_flags) != open_flags) + goto no_delegation_unlock; + + if (delegation == NULL) + delegation = &deleg_cur->stateid; + else if (memcmp(deleg_cur->stateid.data, delegation->data, NFS4_STATEID_SIZE) != 0) + goto no_delegation_unlock; + + __update_open_stateid(state, open_stateid, &deleg_cur->stateid, open_flags); + ret = 1; +no_delegation_unlock: + spin_unlock(&deleg_cur->lock); +no_delegation: + rcu_read_unlock(); + + if (!ret && open_stateid != NULL) { + __update_open_stateid(state, open_stateid, NULL, open_flags); + ret = 1; + } + + return ret; +} + + static void nfs4_return_incompatible_delegation(struct inode *inode, mode_t open_flags) { struct nfs_delegation *delegation; @@ -431,23 +469,23 @@ static struct nfs4_state *nfs4_try_open_cached(struct nfs4_opendata *opendata) nfs4_stateid stateid; int ret = -EAGAIN; - rcu_read_lock(); - delegation = rcu_dereference(nfsi->delegation); for (;;) { if (can_open_cached(state, open_mode)) { spin_lock(&state->owner->so_lock); if (can_open_cached(state, open_mode)) { update_open_stateflags(state, open_mode); spin_unlock(&state->owner->so_lock); - rcu_read_unlock(); goto out_return_state; } spin_unlock(&state->owner->so_lock); } - if (delegation == NULL) - break; - if (!can_open_delegated(delegation, open_mode)) + rcu_read_lock(); + delegation = rcu_dereference(nfsi->delegation); + if (delegation == NULL || + !can_open_delegated(delegation, open_mode)) { + rcu_read_unlock(); break; + } /* Save the delegation */ memcpy(stateid.data, delegation->stateid.data, sizeof(stateid.data)); rcu_read_unlock(); @@ -455,19 +493,11 @@ static struct nfs4_state *nfs4_try_open_cached(struct nfs4_opendata *opendata) if (ret != 0) goto out; ret = -EAGAIN; - rcu_read_lock(); - delegation = rcu_dereference(nfsi->delegation); - /* If no delegation, try a cached open */ - if (delegation == NULL) - continue; - /* Is the delegation still valid? */ - if (memcmp(stateid.data, delegation->stateid.data, sizeof(stateid.data)) != 0) - continue; - rcu_read_unlock(); - update_open_stateid(state, NULL, &stateid, open_mode); - goto out_return_state; + + /* Try to update the stateid using the delegation */ + if (update_open_stateid(state, NULL, &stateid, open_mode)) + goto out_return_state; } - rcu_read_unlock(); out: return ERR_PTR(ret); out_return_state: @@ -480,7 +510,6 @@ static struct nfs4_state *nfs4_opendata_to_nfs4_state(struct nfs4_opendata *data struct inode *inode; struct nfs4_state *state = NULL; struct nfs_delegation *delegation; - nfs4_stateid *deleg_stateid = NULL; int ret; if (!data->rpc_done) { @@ -516,12 +545,9 @@ static struct nfs4_state *nfs4_opendata_to_nfs4_state(struct nfs4_opendata *data data->owner->so_cred, &data->o_res); } - rcu_read_lock(); - delegation = rcu_dereference(NFS_I(inode)->delegation); - if (delegation != NULL) - deleg_stateid = &delegation->stateid; - update_open_stateid(state, &data->o_res.stateid, deleg_stateid, data->o_arg.open_flags); - rcu_read_unlock(); + + update_open_stateid(state, &data->o_res.stateid, NULL, + data->o_arg.open_flags); iput(inode); out: return state; |