[PATCH] knfsd: nfsd4: clean up state initialization
[safe/jmp/linux-2.6] / fs / nfsd / nfs4state.c
index a84a80e..1f68ce3 100644 (file)
@@ -53,7 +53,7 @@
 
 /* Globals */
 static time_t lease_time = 90;     /* default lease time */
-static time_t old_lease_time = 90; /* past incarnation lease time */
+static time_t user_lease_time = 90;
 static u32 nfs4_reclaim_init = 0;
 time_t boot_time;
 static time_t grace_end = 0;
@@ -111,16 +111,36 @@ opaque_hashval(const void *ptr, int nbytes)
 /* forward declarations */
 static void release_stateowner(struct nfs4_stateowner *sop);
 static void release_stateid(struct nfs4_stateid *stp, int flags);
-static void release_file(struct nfs4_file *fp);
 
 /*
  * Delegation state
  */
 
 /* recall_lock protects the del_recall_lru */
-spinlock_t recall_lock;
+spinlock_t recall_lock = SPIN_LOCK_UNLOCKED;
 static struct list_head del_recall_lru;
 
+static void
+free_nfs4_file(struct kref *kref)
+{
+       struct nfs4_file *fp = container_of(kref, struct nfs4_file, fi_ref);
+       list_del(&fp->fi_hash);
+       iput(fp->fi_inode);
+       kmem_cache_free(file_slab, fp);
+}
+
+static inline void
+put_nfs4_file(struct nfs4_file *fi)
+{
+       kref_put(&fi->fi_ref, free_nfs4_file);
+}
+
+static inline void
+get_nfs4_file(struct nfs4_file *fi)
+{
+       kref_get(&fi->fi_ref);
+}
+
 static struct nfs4_delegation *
 alloc_init_deleg(struct nfs4_client *clp, struct nfs4_stateid *stp, struct svc_fh *current_fh, u32 type)
 {
@@ -136,6 +156,7 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_stateid *stp, struct svc_f
        INIT_LIST_HEAD(&dp->dl_del_perclnt);
        INIT_LIST_HEAD(&dp->dl_recall_lru);
        dp->dl_client = clp;
+       get_nfs4_file(fp);
        dp->dl_file = fp;
        dp->dl_flock = NULL;
        get_file(stp->st_vfs_file);
@@ -163,6 +184,7 @@ 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);
        }
 }
@@ -953,6 +975,7 @@ alloc_init_file(struct inode *ino)
 
        fp = kmem_cache_alloc(file_slab, GFP_KERNEL);
        if (fp) {
+               kref_init(&fp->fi_ref);
                INIT_LIST_HEAD(&fp->fi_hash);
                INIT_LIST_HEAD(&fp->fi_stateids);
                INIT_LIST_HEAD(&fp->fi_delegations);
@@ -965,24 +988,6 @@ alloc_init_file(struct inode *ino)
 }
 
 static void
-release_all_files(void)
-{
-       int i;
-       struct nfs4_file *fp;
-
-       for (i=0;i<FILE_HASH_SIZE;i++) {
-               while (!list_empty(&file_hashtbl[i])) {
-                       fp = list_entry(file_hashtbl[i].next, struct nfs4_file, fi_hash);
-                       /* this should never be more than once... */
-                       if (!list_empty(&fp->fi_stateids) || !list_empty(&fp->fi_delegations)) {
-                               printk("ERROR: release_all_files: file %p is open, creating dangling state !!!\n",fp);
-                       }
-                       release_file(fp);
-               }
-       }
-}
-
-static void
 nfsd4_free_slab(kmem_cache_t **slab)
 {
        int status;
@@ -1141,6 +1146,7 @@ init_stateid(struct nfs4_stateid *stp, struct nfs4_file *fp, struct nfsd4_open *
        list_add(&stp->st_perfilestate, &sop->so_perfilestate);
        list_add(&stp->st_perfile, &fp->fi_stateids);
        stp->st_stateowner = sop;
+       get_nfs4_file(fp);
        stp->st_file = fp;
        stp->st_stateid.si_boot = boot_time;
        stp->st_stateid.si_stateownerid = sop->so_id;
@@ -1166,18 +1172,11 @@ release_stateid(struct nfs4_stateid *stp, int flags)
                nfsd_close(filp);
        } else if (flags & LOCK_STATE)
                locks_remove_posix(filp, (fl_owner_t) stp->st_stateowner);
+       put_nfs4_file(stp->st_file);
        kmem_cache_free(stateid_slab, stp);
        stp = NULL;
 }
 
-static void
-release_file(struct nfs4_file *fp)
-{
-       list_del(&fp->fi_hash);
-       iput(fp->fi_inode);
-       kmem_cache_free(file_slab, fp);
-}      
-
 void
 move_to_close_lru(struct nfs4_stateowner *sop)
 {
@@ -1192,7 +1191,6 @@ void
 release_state_owner(struct nfs4_stateid *stp, int flag)
 {
        struct nfs4_stateowner *sop = stp->st_stateowner;
-       struct nfs4_file *fp = stp->st_file;
 
        dprintk("NFSD: release_state_owner\n");
        release_stateid(stp, flag);
@@ -1203,10 +1201,6 @@ release_state_owner(struct nfs4_stateid *stp, int flag)
         */
        if (sop->so_confirmed && list_empty(&sop->so_perfilestate))
                move_to_close_lru(sop);
-       /* unused nfs4_file's are releseed. XXX slab cache? */
-       if (list_empty(&fp->fi_stateids) && list_empty(&fp->fi_delegations)) {
-               release_file(fp);
-       }
 }
 
 static int
@@ -1236,8 +1230,10 @@ find_file(struct inode *ino)
        struct nfs4_file *fp;
 
        list_for_each_entry(fp, &file_hashtbl[hashval], fi_hash) {
-               if (fp->fi_inode == ino)
+               if (fp->fi_inode == ino) {
+                       get_nfs4_file(fp);
                        return fp;
+               }
        }
        return NULL;
 }
@@ -1288,19 +1284,24 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type)
        struct inode *ino = current_fh->fh_dentry->d_inode;
        struct nfs4_file *fp;
        struct nfs4_stateid *stp;
+       int ret;
 
        dprintk("NFSD: nfs4_share_conflict\n");
 
        fp = find_file(ino);
-       if (fp) {
+       if (!fp)
+               return nfs_ok;
+       ret = nfserr_share_denied;
        /* Search for conflicting share reservations */
-               list_for_each_entry(stp, &fp->fi_stateids, st_perfile) {
-                       if (test_bit(deny_type, &stp->st_deny_bmap) ||
-                           test_bit(NFS4_SHARE_DENY_BOTH, &stp->st_deny_bmap))
-                               return nfserr_share_denied;
-               }
+       list_for_each_entry(stp, &fp->fi_stateids, st_perfile) {
+               if (test_bit(deny_type, &stp->st_deny_bmap) ||
+                   test_bit(NFS4_SHARE_DENY_BOTH, &stp->st_deny_bmap))
+                       goto out;
        }
-       return nfs_ok;
+       ret = nfs_ok;
+out:
+       put_nfs4_file(fp);
+       return ret;
 }
 
 static inline void
@@ -1708,14 +1709,30 @@ nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_sta
        int status, flag = 0;
 
        flag = NFS4_OPEN_DELEGATE_NONE;
-       if (open->op_claim_type != NFS4_OPEN_CLAIM_NULL
-            || !atomic_read(&cb->cb_set) || !sop->so_confirmed)
-               goto out;
-
-       if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
-               flag = NFS4_OPEN_DELEGATE_WRITE;
-       else
-               flag = NFS4_OPEN_DELEGATE_READ;
+       open->op_recall = 0;
+       switch (open->op_claim_type) {
+               case NFS4_OPEN_CLAIM_PREVIOUS:
+                       if (!atomic_read(&cb->cb_set))
+                               open->op_recall = 1;
+                       flag = open->op_delegate_type;
+                       if (flag == NFS4_OPEN_DELEGATE_NONE)
+                               goto out;
+                       break;
+               case NFS4_OPEN_CLAIM_NULL:
+                       /* Let's not give out any delegations till everyone's
+                        * had the chance to reclaim theirs.... */
+                       if (nfs4_in_grace())
+                               goto out;
+                       if (!atomic_read(&cb->cb_set) || !sop->so_confirmed)
+                               goto out;
+                       if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
+                               flag = NFS4_OPEN_DELEGATE_WRITE;
+                       else
+                               flag = NFS4_OPEN_DELEGATE_READ;
+                       break;
+               default:
+                       goto out;
+       }
 
        dp = alloc_init_deleg(sop->so_client, stp, fh, flag);
        if (dp == NULL) {
@@ -1749,6 +1766,10 @@ nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_sta
                     dp->dl_stateid.si_fileid,
                     dp->dl_stateid.si_generation);
 out:
+       if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS
+                       && flag == NFS4_OPEN_DELEGATE_NONE
+                       && open->op_delegate_type != NFS4_OPEN_DELEGATE_NONE)
+               printk("NFSD: WARNING: refusing delegation reclaim\n");
        open->op_delegate_type = flag;
 }
 
@@ -1829,10 +1850,8 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
                    stp->st_stateid.si_boot, stp->st_stateid.si_stateownerid,
                    stp->st_stateid.si_fileid, stp->st_stateid.si_generation);
 out:
-       /* take the opportunity to clean up unused state */
-       if (fp && list_empty(&fp->fi_stateids) && list_empty(&fp->fi_delegations))
-               release_file(fp);
-
+       if (fp)
+               put_nfs4_file(fp);
        /* CLAIM_PREVIOUS has different error returns */
        nfs4_set_claim_prev(open, &status);
        /*
@@ -1845,6 +1864,7 @@ out:
        return status;
 }
 
+static struct workqueue_struct *laundry_wq;
 static struct work_struct laundromat_work;
 static void laundromat_main(void *);
 static DECLARE_WORK(laundromat_work, laundromat_main, NULL);
@@ -1952,7 +1972,7 @@ laundromat_main(void *not_used)
 
        t = nfs4_laundromat();
        dprintk("NFSD: laundromat_main - sleeping for %ld seconds\n", t);
-       schedule_delayed_work(&laundromat_work, t*HZ);
+       queue_delayed_work(laundry_wq, &laundromat_work, t*HZ);
 }
 
 /* search ownerid_hashtbl[] and close_lru for stateid owner
@@ -2480,16 +2500,19 @@ find_stateid(stateid_t *stid, int flags)
 static struct nfs4_delegation *
 find_delegation_stateid(struct inode *ino, stateid_t *stid)
 {
-       struct nfs4_file *fp = NULL;
+       struct nfs4_file *fp;
+       struct nfs4_delegation *dl;
 
        dprintk("NFSD:find_delegation_stateid stateid=(%08x/%08x/%08x/%08x)\n",
                     stid->si_boot, stid->si_stateownerid,
                     stid->si_fileid, stid->si_generation);
 
        fp = find_file(ino);
-       if (fp)
-               return find_delegation_file(fp, stid);
-       return NULL;
+       if (!fp)
+               return NULL;
+       dl = find_delegation_file(fp, stid);
+       put_nfs4_file(fp);
+       return dl;
 }
 
 /*
@@ -2636,6 +2659,7 @@ alloc_init_lock_stateid(struct nfs4_stateowner *sop, struct nfs4_file *fp, struc
        list_add(&stp->st_perfile, &fp->fi_stateids);
        list_add(&stp->st_perfilestate, &sop->so_perfilestate);
        stp->st_stateowner = sop;
+       get_nfs4_file(fp);
        stp->st_file = fp;
        stp->st_stateid.si_boot = boot_time;
        stp->st_stateid.si_stateownerid = sop->so_id;
@@ -3152,30 +3176,16 @@ nfs4_find_reclaim_client(clientid_t *clid)
 int
 nfs4_check_open_reclaim(clientid_t *clid)
 {
-       struct nfs4_client_reclaim *crp;
-
-       if ((crp = nfs4_find_reclaim_client(clid)) == NULL)
-               return nfserr_reclaim_bad;
-       return nfs_ok;
+       return nfs4_find_reclaim_client(clid) ? nfs_ok : nfserr_reclaim_bad;
 }
 
+/* initialization to perform at module load time: */
 
-/* 
- * Start and stop routines
- */
-
-static void
-__nfs4_state_init(void)
+void
+nfs4_state_init(void)
 {
        int i;
-       time_t grace_time;
 
-       if (!nfs4_reclaim_init) {
-               for (i = 0; i < CLIENT_HASH_SIZE; i++)
-                       INIT_LIST_HEAD(&reclaim_str_hashtbl[i]);
-               reclaim_str_hashtbl_size = 0;
-               nfs4_reclaim_init = 1;
-       }
        for (i = 0; i < CLIENT_HASH_SIZE; i++) {
                INIT_LIST_HEAD(&conf_id_hashtbl[i]);
                INIT_LIST_HEAD(&conf_str_hashtbl[i]);
@@ -3197,26 +3207,34 @@ __nfs4_state_init(void)
                INIT_LIST_HEAD(&lock_ownerid_hashtbl[i]);
                INIT_LIST_HEAD(&lock_ownerstr_hashtbl[i]);
        }
-       memset(&zerostateid, 0, sizeof(stateid_t));
        memset(&onestateid, ~0, sizeof(stateid_t));
-
        INIT_LIST_HEAD(&close_lru);
        INIT_LIST_HEAD(&client_lru);
        INIT_LIST_HEAD(&del_recall_lru);
-       spin_lock_init(&recall_lock);
+       for (i = 0; i < CLIENT_HASH_SIZE; i++)
+               INIT_LIST_HEAD(&reclaim_str_hashtbl[i]);
+       reclaim_str_hashtbl_size = 0;
+       nfs4_reclaim_init = 1;
+}
+
+/* initialization to perform when the nfsd service is started: */
+
+static void
+__nfs4_state_start(void)
+{
+       time_t grace_time;
+
        boot_time = get_seconds();
-       grace_time = max(old_lease_time, lease_time);
-       if (reclaim_str_hashtbl_size == 0)
-               grace_time = 0;
-       if (grace_time)
-               printk("NFSD: starting %ld-second grace period\n", grace_time);
+       grace_time = max(user_lease_time, lease_time);
+       lease_time = user_lease_time;
+       printk("NFSD: starting %ld-second grace period\n", grace_time);
        grace_end = boot_time + grace_time;
-       INIT_WORK(&laundromat_work,laundromat_main, NULL);
-       schedule_delayed_work(&laundromat_work, NFSD_LEASE_TIME*HZ);
+       laundry_wq = create_singlethread_workqueue("nfsd4");
+       queue_delayed_work(laundry_wq, &laundromat_work, NFSD_LEASE_TIME*HZ);
 }
 
 int
-nfs4_state_init(void)
+nfs4_state_start(void)
 {
        int status;
 
@@ -3225,7 +3243,7 @@ nfs4_state_init(void)
        status = nfsd4_init_slabs();
        if (status)
                return status;
-       __nfs4_state_init();
+       __nfs4_state_start();
        nfs4_init = 1;
        return 0;
 }
@@ -3287,9 +3305,9 @@ __nfs4_state_shutdown(void)
                unhash_delegation(dp);
        }
 
-       release_all_files();
        cancel_delayed_work(&laundromat_work);
-       flush_scheduled_work();
+       flush_workqueue(laundry_wq);
+       destroy_workqueue(laundry_wq);
        nfs4_init = 0;
 }
 
@@ -3306,53 +3324,16 @@ nfs4_state_shutdown(void)
 /*
  * Called when leasetime is changed.
  *
- * if nfsd is not started, simply set the global lease.
- *
- * if nfsd(s) are running, lease change requires nfsv4 state to be reset.
- * e.g: boot_time is reset, existing nfs4_client structs are
- * used to fill reclaim_str_hashtbl, then all state (except for the
- * reclaim_str_hashtbl) is re-initialized.
- *
- * if the old lease time is greater than the new lease time, the grace
- * period needs to be set to the old lease time to allow clients to reclaim
- * their state. XXX - we may want to set the grace period == lease time
- * after an initial grace period == old lease time
- *
- * if an error occurs in this process, the new lease is set, but the server
- * will not honor OPEN or LOCK reclaims, and will return nfserr_no_grace
- * which means OPEN/LOCK/READ/WRITE will fail during grace period.
- *
- * clients will attempt to reset all state with SETCLIENTID/CONFIRM, and
- * OPEN and LOCK reclaims.
+ * The only way the protocol gives us to handle on-the-fly lease changes is to
+ * simulate a reboot.  Instead of doing that, we just wait till the next time
+ * we start to register any changes in lease time.  If the administrator
+ * really wants to change the lease time *now*, they can go ahead and bring
+ * nfsd down and then back up again after changing the lease time.
  */
 void
 nfs4_reset_lease(time_t leasetime)
 {
-       struct nfs4_client *clp;
-       int i;
-
-       printk("NFSD: New leasetime %ld\n",leasetime);
-       if (!nfs4_init)
-               return;
-       nfs4_lock_state();
-       old_lease_time = lease_time;
-       lease_time = leasetime;
-
-       nfs4_release_reclaim();
-
-       /* populate reclaim_str_hashtbl with current confirmed nfs4_clientid */
-       for (i = 0; i < CLIENT_HASH_SIZE; i++) {
-               list_for_each_entry(clp, &conf_id_hashtbl[i], cl_idhash) {
-                       if (!nfs4_client_to_reclaim(clp->cl_name.data,
-                                               clp->cl_name.len)) {
-                               nfs4_release_reclaim();
-                               goto init_state;
-                       }
-               }
-       }
-init_state:
-       __nfs4_state_shutdown();
-       __nfs4_state_init();
-       nfs4_unlock_state();
+       lock_kernel();
+       user_lease_time = leasetime;
+       unlock_kernel();
 }
-