diff options
Diffstat (limited to 'fs/nfsd')
| -rw-r--r-- | fs/nfsd/nfs4state.c | 81 |
1 files changed, 52 insertions, 29 deletions
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index a6637de7ae13..27c77a0b423f 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -261,33 +261,46 @@ static inline int get_new_stid(struct nfs4_stid *stid) return new_stid; } -static void init_stid(struct nfs4_stid *stid, struct nfs4_client *cl, unsigned char type) +static struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct +kmem_cache *slab) { - stateid_t *s = &stid->sc_stateid; + struct idr *stateids = &cl->cl_stateids; + static int min_stateid = 0; + struct nfs4_stid *stid; int new_id; - stid->sc_type = type; + stid = kmem_cache_alloc(slab, GFP_KERNEL); + if (!stid) + return NULL; + + if (!idr_pre_get(stateids, GFP_KERNEL)) + goto out_free; + if (idr_get_new_above(stateids, stid, min_stateid, &new_id)) + goto out_free; stid->sc_client = cl; - s->si_opaque.so_clid = cl->cl_clientid; - new_id = get_new_stid(stid); - s->si_opaque.so_id = (u32)new_id; + stid->sc_type = 0; + stid->sc_stateid.si_opaque.so_id = new_id; + stid->sc_stateid.si_opaque.so_clid = cl->cl_clientid; /* Will be incremented before return to client: */ - s->si_generation = 0; -} + stid->sc_stateid.si_generation = 0; -static struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab) -{ - struct idr *stateids = &cl->cl_stateids; - - if (!idr_pre_get(stateids, GFP_KERNEL)) - return NULL; /* - * Note: if we fail here (or any time between now and the time - * we actually get the new idr), we won't need to undo the idr - * preallocation, since the idr code caps the number of - * preallocated entries. + * It shouldn't be a problem to reuse an opaque stateid value. + * I don't think it is for 4.1. But with 4.0 I worry that, for + * example, a stray write retransmission could be accepted by + * the server when it should have been rejected. Therefore, + * adopt a trick from the sctp code to attempt to maximize the + * amount of time until an id is reused, by ensuring they always + * "increase" (mod INT_MAX): */ - return kmem_cache_alloc(slab, GFP_KERNEL); + + min_stateid = new_id+1; + if (min_stateid == INT_MAX) + min_stateid = 0; + return stid; +out_free: + kfree(stid); + return NULL; } static struct nfs4_ol_stateid * nfs4_alloc_stateid(struct nfs4_client *clp) @@ -316,7 +329,7 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct sv dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab)); if (dp == NULL) return dp; - init_stid(&dp->dl_stid, clp, NFS4_DELEG_STID); + dp->dl_stid.sc_type = NFS4_DELEG_STID; /* * delegation seqid's are never incremented. The 4.1 special * meaning of seqid 0 isn't meaningful, really, but let's avoid @@ -337,13 +350,21 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct sv return dp; } +void free_stid(struct nfs4_stid *s, struct kmem_cache *slab) +{ + struct idr *stateids = &s->sc_client->cl_stateids; + + idr_remove(stateids, s->sc_stateid.si_opaque.so_id); + kmem_cache_free(slab, s); +} + void nfs4_put_delegation(struct nfs4_delegation *dp) { if (atomic_dec_and_test(&dp->dl_count)) { dprintk("NFSD: freeing dp %p\n",dp); put_nfs4_file(dp->dl_file); - kmem_cache_free(deleg_slab, dp); + free_stid(&dp->dl_stid, deleg_slab); num_delegations--; } } @@ -360,9 +381,7 @@ static void nfs4_put_deleg_lease(struct nfs4_file *fp) static void unhash_stid(struct nfs4_stid *s) { - struct idr *stateids = &s->sc_client->cl_stateids; - - idr_remove(stateids, s->sc_stateid.si_opaque.so_id); + s->sc_type = 0; } /* Called under the state lock. */ @@ -519,7 +538,7 @@ static void close_generic_stateid(struct nfs4_ol_stateid *stp) static void free_generic_stateid(struct nfs4_ol_stateid *stp) { - kmem_cache_free(stateid_slab, stp); + free_stid(&stp->st_stid, stateid_slab); } static void release_lock_stateid(struct nfs4_ol_stateid *stp) @@ -1260,7 +1279,12 @@ static void gen_confirm(struct nfs4_client *clp) static struct nfs4_stid *find_stateid(struct nfs4_client *cl, stateid_t *t) { - return idr_find(&cl->cl_stateids, t->si_opaque.so_id); + struct nfs4_stid *ret; + + ret = idr_find(&cl->cl_stateids, t->si_opaque.so_id); + if (!ret || !ret->sc_type) + return NULL; + return ret; } static struct nfs4_stid *find_stateid_by_type(struct nfs4_client *cl, stateid_t *t, char typemask) @@ -2446,9 +2470,8 @@ alloc_init_open_stateowner(unsigned int strhashval, struct nfs4_client *clp, str static void init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp, struct nfsd4_open *open) { struct nfs4_openowner *oo = open->op_openowner; - struct nfs4_client *clp = oo->oo_owner.so_client; - init_stid(&stp->st_stid, clp, NFS4_OPEN_STID); + stp->st_stid.sc_type = NFS4_OPEN_STID; INIT_LIST_HEAD(&stp->st_lockowners); list_add(&stp->st_perstateowner, &oo->oo_owner.so_stateids); list_add(&stp->st_perfile, &fp->fi_stateids); @@ -4034,7 +4057,7 @@ alloc_init_lock_stateid(struct nfs4_lockowner *lo, struct nfs4_file *fp, struct stp = nfs4_alloc_stateid(clp); if (stp == NULL) return NULL; - init_stid(&stp->st_stid, clp, NFS4_LOCK_STID); + stp->st_stid.sc_type = NFS4_LOCK_STID; list_add(&stp->st_perfile, &fp->fi_stateids); list_add(&stp->st_perstateowner, &lo->lo_owner.so_stateids); stp->st_stateowner = &lo->lo_owner; |