type->typ_md_ops = kzalloc(sizeof(*type->typ_md_ops), GFP_NOFS);
        type->typ_name = kzalloc(strlen(name) + 1, GFP_NOFS);
 
-       if (type->typ_dt_ops == NULL ||
-           type->typ_md_ops == NULL ||
-           type->typ_name == NULL)
+       if (!type->typ_dt_ops ||
+           !type->typ_md_ops ||
+           !type->typ_name)
                goto failed;
 
        *(type->typ_dt_ops) = *dt_ops;
        }
 
        type = class_get_type(type_name);
-       if (type == NULL) {
+       if (!type) {
                CERROR("OBD: unknown type: %s\n", type_name);
                return ERR_PTR(-ENODEV);
        }
 
        newdev = obd_device_alloc();
-       if (newdev == NULL) {
+       if (!newdev) {
                result = ERR_PTR(-ENOMEM);
                goto out_type;
        }
        }
        write_unlock(&obd_dev_lock);
 
-       if (result == NULL && i >= class_devno_max()) {
+       if (!result && i >= class_devno_max()) {
                CERROR("all %u OBD devices used, increase MAX_OBD_DEVICES\n",
                       class_devno_max());
                result = ERR_PTR(-EOVERFLOW);
 
        if (num < class_devno_max()) {
                obd = obd_devs[num];
-               if (obd == NULL)
+               if (!obd)
                        return NULL;
 
                LASSERTF(obd->obd_magic == OBD_DEVICE_MAGIC,
        for (i = 0; i < class_devno_max(); i++) {
                struct obd_device *obd = class_num2obd(i);
 
-               if (obd == NULL)
+               if (!obd)
                        continue;
                if (obd->obd_stopping)
                        status = "ST";
        for (i = 0; i < class_devno_max(); i++) {
                struct obd_device *obd = class_num2obd(i);
 
-               if (obd == NULL)
+               if (!obd)
                        continue;
                if ((strncmp(obd->obd_type->typ_name, typ_name,
                             strlen(typ_name)) == 0)) {
 {
        int i;
 
-       if (next == NULL)
+       if (!next)
                i = 0;
        else if (*next >= 0 && *next < class_devno_max())
                i = *next;
        for (; i < class_devno_max(); i++) {
                struct obd_device *obd = class_num2obd(i);
 
-               if (obd == NULL)
+               if (!obd)
                        continue;
                if (obd_uuid_equals(grp_uuid, &obd->obd_uuid)) {
-                       if (next != NULL)
+                       if (next)
                                *next = i+1;
                        read_unlock(&obd_dev_lock);
                        return obd;
        for (i = 0; i < class_devno_max(); i++) {
                obd = class_num2obd(i);
 
-               if (obd == NULL || obd->obd_set_up == 0 || obd->obd_stopping)
+               if (!obd || obd->obd_set_up == 0 || obd->obd_stopping)
                        continue;
 
                /* only notify mdc, osc, mdt, ost */
 
 int obd_init_caches(void)
 {
-       LASSERT(obd_device_cachep == NULL);
+       LASSERT(!obd_device_cachep);
        obd_device_cachep = kmem_cache_create("ll_obd_dev_cache",
                                                 sizeof(struct obd_device),
                                                 0, 0, NULL);
        if (!obd_device_cachep)
                goto out;
 
-       LASSERT(obdo_cachep == NULL);
+       LASSERT(!obdo_cachep);
        obdo_cachep = kmem_cache_create("ll_obdo_cache", sizeof(struct obdo),
                                           0, 0, NULL);
        if (!obdo_cachep)
                goto out;
 
-       LASSERT(import_cachep == NULL);
+       LASSERT(!import_cachep);
        import_cachep = kmem_cache_create("ll_import_cache",
                                             sizeof(struct obd_import),
                                             0, 0, NULL);
        if (!import_cachep)
                goto out;
 
-       LASSERT(capa_cachep == NULL);
+       LASSERT(!capa_cachep);
        capa_cachep = kmem_cache_create("capa_cache",
                                           sizeof(struct obd_capa), 0, 0, NULL);
        if (!capa_cachep)
 {
        struct obd_device *obd = exp->exp_obd;
 
-       if (obd == NULL)
+       if (!obd)
                return NULL;
        return obd->u.cli.cl_import;
 }
 {
        struct obd_device *obd = class_conn2obd(conn);
 
-       if (obd == NULL)
+       if (!obd)
                return NULL;
        return obd->u.cli.cl_import;
 }
        }
 
        hash = cfs_hash_getref(obd->obd_uuid_hash);
-       if (hash == NULL) {
+       if (!hash) {
                rc = -ENODEV;
                goto exit_unlock;
        }
                kfree(imp_conn);
        }
 
-       LASSERT(imp->imp_sec == NULL);
+       LASSERT(!imp->imp_sec);
        class_decref(imp->imp_obd, "import", imp);
        OBD_FREE_RCU(imp, sizeof(*imp), &imp->imp_handle);
 }
 {
        int already_disconnected;
 
-       if (export == NULL) {
+       if (!export) {
                CWARN("attempting to free NULL export %p\n", export);
                return -EINVAL;
        }
                evicted++;
                CDEBUG(D_HA, "%s: disconnect stale client %s@%s\n",
                       obd->obd_name, exp->exp_client_uuid.uuid,
-                      exp->exp_connection == NULL ? "<unknown>" :
+                      !exp->exp_connection ? "<unknown>" :
                       libcfs_nid2str(exp->exp_connection->c_peer.nid));
                print_export_data(exp, "EVICTING", 0);
        }
 
        do {
                doomed_exp = cfs_hash_lookup(nid_hash, &nid_key);
-               if (doomed_exp == NULL)
+               if (!doomed_exp)
                        break;
 
                LASSERTF(doomed_exp->exp_connection->c_peer.nid == nid_key,
 
        doomed_exp = cfs_hash_lookup(uuid_hash, &doomed_uuid);
 
-       if (doomed_exp == NULL) {
+       if (!doomed_exp) {
                CERROR("%s: can't disconnect %s: no exports found\n",
                       obd->obd_name, uuid);
        } else {
  */
 static void obd_zombie_import_add(struct obd_import *imp)
 {
-       LASSERT(imp->imp_sec == NULL);
-       LASSERT(imp->imp_rq_pool == NULL);
+       LASSERT(!imp->imp_sec);
+       LASSERT(!imp->imp_rq_pool);
        spin_lock(&obd_zombie_impexp_lock);
        LASSERT(list_empty(&imp->imp_zombie_chain));
        zombies_count++;