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LU-7542 obdclass: quiet lockdep recursive lock warning
[fs/lustre-release.git] / lustre / ptlrpc / nodemap_storage.c
index cd396a9..b117120 100644 (file)
 #include <obd_support.h>
 #include "nodemap_internal.h"
 
-/* list of registered nodemap index files */
+/* list of registered nodemap index files, except MGS */
 static LIST_HEAD(ncf_list_head);
 static DEFINE_MUTEX(ncf_list_lock);
 
+/* MGS index is different than others, others are listeners to MGS idx */
+static struct nm_config_file *nodemap_mgs_ncf;
+
 /* lu_nodemap flags */
 enum nm_flag_shifts {
        NM_FL_ALLOW_ROOT_ACCESS = 0x1,
@@ -145,7 +148,7 @@ static void nodemap_inc_version(const struct lu_env *env,
        dt_version_set(env, nodemap_idx, ver + 1, th);
 }
 
-static int nodemap_idx_insert(struct lu_env *env,
+static int nodemap_idx_insert(const struct lu_env *env,
                              struct dt_object *idx,
                              const struct nodemap_key *nk,
                              const union nodemap_rec *nr)
@@ -188,7 +191,7 @@ out:
        return rc;
 }
 
-static int nodemap_idx_update(struct lu_env *env,
+static int nodemap_idx_update(const struct lu_env *env,
                              struct dt_object *idx,
                              const struct nodemap_key *nk,
                              const union nodemap_rec *nr)
@@ -239,7 +242,7 @@ out:
        return rc;
 }
 
-static int nodemap_idx_delete(struct lu_env *env,
+static int nodemap_idx_delete(const struct lu_env *env,
                              struct dt_object *idx,
                              const struct nodemap_key *nk,
                              const union nodemap_rec *unused)
@@ -278,46 +281,6 @@ out:
        return rc;
 }
 
-typedef int (*nm_idx_cb_t)(struct lu_env *env,
-                          struct dt_object *idx,
-                          const struct nodemap_key *nk,
-                          const union nodemap_rec *nr);
-
-/**
- * Iterates through all the registered nodemap_config_files and calls the
- * given callback with the ncf as a parameter, as well as the given key and rec.
- *
- * \param      cb_f            callback function to call
- * \param      nk              key of the record to act upon
- * \param      nr              record to act upon, NULL for the delete action
- */
-static int nodemap_idx_action(nm_idx_cb_t cb_f, struct nodemap_key *nk,
-                             union nodemap_rec *nr)
-{
-       struct nm_config_file   *ncf;
-       struct lu_env            env;
-       int                      rc = 0;
-       int                      rc2 = 0;
-
-       rc = lu_env_init(&env, LCT_LOCAL);
-       if (rc != 0)
-               return rc;
-
-       mutex_lock(&ncf_list_lock);
-       list_for_each_entry(ncf, &ncf_list_head, ncf_list) {
-               rc2 = cb_f(&env, ncf->ncf_obj, nk, nr);
-               if (rc2 < 0) {
-                       CWARN("%s: error writing to nodemap config: rc = %d\n",
-                             ncf->ncf_obj->do_lu.lo_dev->ld_obd->obd_name, rc);
-                       rc = rc2;
-               }
-       }
-       mutex_unlock(&ncf_list_lock);
-       lu_env_fini(&env);
-
-       return 0;
-}
-
 enum nm_add_update {
        NM_ADD = 0,
        NM_UPDATE = 1,
@@ -326,19 +289,33 @@ enum nm_add_update {
 static int nodemap_idx_nodemap_add_update(const struct lu_nodemap *nodemap,
                                          enum nm_add_update update)
 {
-       struct nodemap_key       nk;
-       union nodemap_rec        nr;
+       struct nodemap_key nk;
+       union nodemap_rec nr;
+       struct lu_env env;
        int rc = 0;
 
        ENTRY;
 
+       if (nodemap_mgs_ncf == NULL) {
+               CERROR("cannot add nodemap config to non-existing MGS.\n");
+               return -EINVAL;
+       }
+
+       rc = lu_env_init(&env, LCT_LOCAL);
+       if (rc)
+               RETURN(rc);
+
        nodemap_cluster_key_init(&nk, nodemap->nm_id);
        nodemap_cluster_rec_init(&nr, nodemap);
 
        if (update == NM_UPDATE)
-               rc = nodemap_idx_action(nodemap_idx_update, &nk, &nr);
+               rc = nodemap_idx_update(&env, nodemap_mgs_ncf->ncf_obj,
+                                       &nk, &nr);
        else
-               rc = nodemap_idx_action(nodemap_idx_insert, &nk, &nr);
+               rc = nodemap_idx_insert(&env, nodemap_mgs_ncf->ncf_obj,
+                                       &nk, &nr);
+
+       lu_env_fini(&env);
 
        RETURN(rc);
 }
@@ -361,17 +338,28 @@ int nodemap_idx_nodemap_del(const struct lu_nodemap *nodemap)
        struct lu_nid_range     *range;
        struct lu_nid_range     *range_temp;
        struct nodemap_key       nk;
+       struct lu_env            env;
        int                      rc = 0;
        int                      rc2 = 0;
 
        ENTRY;
 
+       if (nodemap_mgs_ncf == NULL) {
+               CERROR("cannot add nodemap config to non-existing MGS.\n");
+               return -EINVAL;
+       }
+
+       rc = lu_env_init(&env, LCT_LOCAL);
+       if (rc != 0)
+               RETURN(rc);
+
        root = nodemap->nm_fs_to_client_uidmap;
        nm_rbtree_postorder_for_each_entry_safe(idmap, temp, &root,
                                                id_fs_to_client) {
                nodemap_idmap_key_init(&nk, nodemap->nm_id, NODEMAP_UID,
                                       idmap->id_client);
-               rc2 = nodemap_idx_action(nodemap_idx_delete, &nk, NULL);
+               rc2 = nodemap_idx_delete(&env, nodemap_mgs_ncf->ncf_obj,
+                                        &nk, NULL);
                if (rc2 < 0)
                        rc = rc2;
        }
@@ -381,7 +369,8 @@ int nodemap_idx_nodemap_del(const struct lu_nodemap *nodemap)
                                                id_client_to_fs) {
                nodemap_idmap_key_init(&nk, nodemap->nm_id, NODEMAP_GID,
                                       idmap->id_client);
-               rc2 = nodemap_idx_action(nodemap_idx_delete, &nk, NULL);
+               rc2 = nodemap_idx_delete(&env, nodemap_mgs_ncf->ncf_obj,
+                                        &nk, NULL);
                if (rc2 < 0)
                        rc = rc2;
        }
@@ -389,16 +378,19 @@ int nodemap_idx_nodemap_del(const struct lu_nodemap *nodemap)
        list_for_each_entry_safe(range, range_temp, &nodemap->nm_ranges,
                                 rn_list) {
                nodemap_range_key_init(&nk, nodemap->nm_id, range->rn_id);
-               rc2 = nodemap_idx_action(nodemap_idx_delete, &nk, NULL);
+               rc2 = nodemap_idx_delete(&env, nodemap_mgs_ncf->ncf_obj,
+                                        &nk, NULL);
                if (rc2 < 0)
                        rc = rc2;
        }
 
        nodemap_cluster_key_init(&nk, nodemap->nm_id);
-       rc2 = nodemap_idx_action(nodemap_idx_delete, &nk, NULL);
+       rc2 = nodemap_idx_delete(&env, nodemap_mgs_ncf->ncf_obj, &nk, NULL);
        if (rc2 < 0)
                rc = rc2;
 
+       lu_env_fini(&env);
+
        RETURN(rc);
 }
 
@@ -407,22 +399,50 @@ int nodemap_idx_range_add(const struct lu_nid_range *range,
 {
        struct nodemap_key       nk;
        union nodemap_rec        nr;
+       struct lu_env            env;
+       int                      rc = 0;
        ENTRY;
 
+       if (nodemap_mgs_ncf == NULL) {
+               CERROR("cannot add nodemap config to non-existing MGS.\n");
+               return -EINVAL;
+       }
+
+       rc = lu_env_init(&env, LCT_LOCAL);
+       if (rc != 0)
+               RETURN(rc);
+
        nodemap_range_key_init(&nk, range->rn_nodemap->nm_id, range->rn_id);
        nodemap_range_rec_init(&nr, nid);
 
-       RETURN(nodemap_idx_action(nodemap_idx_insert, &nk, &nr));
+       rc = nodemap_idx_insert(&env, nodemap_mgs_ncf->ncf_obj, &nk, &nr);
+       lu_env_fini(&env);
+
+       RETURN(rc);
 }
 
 int nodemap_idx_range_del(const struct lu_nid_range *range)
 {
        struct nodemap_key       nk;
+       struct lu_env            env;
+       int                      rc = 0;
        ENTRY;
 
+       if (nodemap_mgs_ncf == NULL) {
+               CERROR("cannot add nodemap config to non-existing MGS.\n");
+               return -EINVAL;
+       }
+
+       rc = lu_env_init(&env, LCT_LOCAL);
+       if (rc != 0)
+               RETURN(rc);
+
        nodemap_range_key_init(&nk, range->rn_nodemap->nm_id, range->rn_id);
 
-       RETURN(nodemap_idx_action(nodemap_idx_delete, &nk, NULL));
+       rc = nodemap_idx_delete(&env, nodemap_mgs_ncf->ncf_obj, &nk, NULL);
+       lu_env_fini(&env);
+
+       RETURN(rc);
 }
 
 int nodemap_idx_idmap_add(const struct lu_nodemap *nodemap,
@@ -431,12 +451,26 @@ int nodemap_idx_idmap_add(const struct lu_nodemap *nodemap,
 {
        struct nodemap_key       nk;
        union nodemap_rec        nr;
+       struct lu_env            env;
+       int                      rc = 0;
        ENTRY;
 
+       if (nodemap_mgs_ncf == NULL) {
+               CERROR("cannot add nodemap config to non-existing MGS.\n");
+               return -EINVAL;
+       }
+
+       rc = lu_env_init(&env, LCT_LOCAL);
+       if (rc != 0)
+               RETURN(rc);
+
        nodemap_idmap_key_init(&nk, nodemap->nm_id, id_type, map[0]);
        nodemap_idmap_rec_init(&nr, map[1]);
 
-       RETURN(nodemap_idx_action(nodemap_idx_insert, &nk, &nr));
+       rc = nodemap_idx_insert(&env, nodemap_mgs_ncf->ncf_obj, &nk, &nr);
+       lu_env_fini(&env);
+
+       RETURN(rc);
 }
 
 int nodemap_idx_idmap_del(const struct lu_nodemap *nodemap,
@@ -444,26 +478,57 @@ int nodemap_idx_idmap_del(const struct lu_nodemap *nodemap,
                          const u32 map[2])
 {
        struct nodemap_key       nk;
+       struct lu_env            env;
+       int                      rc = 0;
        ENTRY;
 
+       if (nodemap_mgs_ncf == NULL) {
+               CERROR("cannot add nodemap config to non-existing MGS.\n");
+               return -EINVAL;
+       }
+
+       rc = lu_env_init(&env, LCT_LOCAL);
+       if (rc != 0)
+               RETURN(rc);
+
        nodemap_idmap_key_init(&nk, nodemap->nm_id, id_type, map[0]);
 
-       RETURN(nodemap_idx_action(nodemap_idx_delete, &nk, NULL));
+       rc = nodemap_idx_delete(&env, nodemap_mgs_ncf->ncf_obj, &nk, NULL);
+       lu_env_fini(&env);
+
+       RETURN(rc);
 }
 
 static int nodemap_idx_global_add_update(bool value, enum nm_add_update update)
 {
        struct nodemap_key       nk;
        union nodemap_rec        nr;
+       struct lu_env            env;
+       int                      rc = 0;
        ENTRY;
 
+       if (nodemap_mgs_ncf == NULL) {
+               CERROR("cannot add nodemap config to non-existing MGS.\n");
+               return -EINVAL;
+       }
+
+       rc = lu_env_init(&env, LCT_LOCAL);
+       if (rc != 0)
+               RETURN(rc);
+
        nodemap_global_key_init(&nk);
        nodemap_global_rec_init(&nr, value);
 
        if (update == NM_UPDATE)
-               RETURN(nodemap_idx_action(nodemap_idx_update, &nk, &nr));
+               rc = nodemap_idx_update(&env, nodemap_mgs_ncf->ncf_obj,
+                                       &nk, &nr);
        else
-               RETURN(nodemap_idx_action(nodemap_idx_insert, &nk, &nr));
+               rc = nodemap_idx_insert(&env, nodemap_mgs_ncf->ncf_obj,
+                                       &nk, &nr);
+
+       lu_env_fini(&env);
+
+       RETURN(rc);
 }
 
 int nodemap_idx_nodemap_activate(bool value)
@@ -504,6 +569,9 @@ static int nodemap_process_keyrec(struct nodemap_config *config,
        type = nm_idx_get_type(nodemap_id);
        nodemap_id = nm_idx_set_type(nodemap_id, 0);
 
+       CDEBUG(D_INFO, "found config entry, nm_id %d type %d\n",
+              nodemap_id, type);
+
        /* find the correct nodemap in the load list */
        if (type == NODEMAP_RANGE_IDX || type == NODEMAP_UIDMAP_IDX ||
            type == NODEMAP_GIDMAP_IDX) {
@@ -612,6 +680,7 @@ static int nodemap_process_keyrec(struct nodemap_config *config,
                CERROR("got keyrec pair for unknown type %d\n", type);
                break;
        }
+
        rc = type;
 
 out:
@@ -646,7 +715,6 @@ static int nodemap_load_entries(const struct lu_env *env,
                        GOTO(out_iops, rc = 0);
        }
 
-       /* acquires active config lock */
        new_config = nodemap_config_alloc();
        if (IS_ERR(new_config)) {
                rc = PTR_ERR(new_config);
@@ -706,14 +774,21 @@ out:
                        rc = PTR_ERR(new_config->nmc_default_nodemap);
                } else {
                        rc = nodemap_idx_nodemap_add_update(
-                                       new_config->nmc_default_nodemap, 0);
+                                       new_config->nmc_default_nodemap,
+                                       NM_ADD);
                        nodemap_putref(new_config->nmc_default_nodemap);
                }
        }
 
        /* new nodemap config won't have an active/inactive record */
-       if (rc == 0 && loaded_global_idx == false)
-               rc = nodemap_idx_global_add_update(false, NM_ADD);
+       if (rc == 0 && loaded_global_idx == false) {
+               struct nodemap_key       nk;
+               union nodemap_rec        nr;
+
+               nodemap_global_key_init(&nk);
+               nodemap_global_rec_init(&nr, false);
+               rc = nodemap_idx_insert(env, nodemap_idx, &nk, &nr);
+       }
 
        if (rc == 0)
                nodemap_config_set_active(new_config);
@@ -723,6 +798,25 @@ out:
        RETURN(rc);
 }
 
+/* tracks if config still needs to be loaded, either from disk or network */
+static bool nodemap_config_loaded;
+static DEFINE_MUTEX(nodemap_config_loaded_lock);
+
+/**
+ * Ensures that configs loaded over the wire are prioritized over those loaded
+ * from disk.
+ *
+ * \param config       config to set as the active config
+ */
+void nodemap_config_set_active_mgc(struct nodemap_config *config)
+{
+       mutex_lock(&nodemap_config_loaded_lock);
+       nodemap_config_set_active(config);
+       nodemap_config_loaded = true;
+       mutex_unlock(&nodemap_config_loaded_lock);
+}
+EXPORT_SYMBOL(nodemap_config_set_active_mgc);
+
 /**
  * Register a dt_object representing the config index file. This should be
  * called by targets in order to load the nodemap configuration from disk. The
@@ -737,11 +831,12 @@ out:
  * \retval     -EINVAL         error loading nodemap config
  */
 struct nm_config_file *nm_config_file_register(const struct lu_env *env,
-                                              struct dt_object *obj)
+                                              struct dt_object *obj,
+                                              struct local_oid_storage *los,
+                                              enum nm_config_file_type ncf_type)
 {
        struct nm_config_file *ncf;
-       bool load_entries = false;
-       int rc;
+       int rc = 0;
        ENTRY;
 
        OBD_ALLOC_PTR(ncf);
@@ -749,24 +844,36 @@ struct nm_config_file *nm_config_file_register(const struct lu_env *env,
                RETURN(ERR_PTR(-ENOMEM));
 
        ncf->ncf_obj = obj;
-       mutex_lock(&ncf_list_lock);
-
-       /* if this is first config file, we load it from disk */
-       if (list_empty(&ncf_list_head))
-               load_entries = true;
-
-       list_add(&ncf->ncf_list, &ncf_list_head);
-       mutex_unlock(&ncf_list_lock);
+       ncf->ncf_los = los;
+
+       if (ncf_type == NCFT_MGS) {
+               nodemap_mgs_ncf = ncf;
+       } else {
+               mutex_lock(&ncf_list_lock);
+               list_add(&ncf->ncf_list, &ncf_list_head);
+               mutex_unlock(&ncf_list_lock);
+       }
 
-       if (load_entries) {
+       /* prevent activation of config loaded from MGS until disk is loaded
+        * so disk config is overwritten by MGS config.
+        */
+       mutex_lock(&nodemap_config_loaded_lock);
+       if (ncf_type == NCFT_MGS || !nodemap_config_loaded)
                rc = nodemap_load_entries(env, obj);
-               if (rc < 0) {
+       nodemap_config_loaded = true;
+       mutex_unlock(&nodemap_config_loaded_lock);
+
+       if (rc < 0) {
+               if (ncf_type == NCFT_MGS) {
+                       nodemap_mgs_ncf = NULL;
+               } else {
                        mutex_lock(&ncf_list_lock);
                        list_del(&ncf->ncf_list);
                        mutex_unlock(&ncf_list_lock);
-                       OBD_FREE_PTR(ncf);
-                       RETURN(ERR_PTR(rc));
                }
+
+               OBD_FREE_PTR(ncf);
+               RETURN(ERR_PTR(rc));
        }
 
        RETURN(ncf);
@@ -779,17 +886,196 @@ EXPORT_SYMBOL(nm_config_file_register);
  * \param ncf  config file to deregister
  */
 void nm_config_file_deregister(const struct lu_env *env,
-                              struct nm_config_file *ncf)
+                              struct nm_config_file *ncf,
+                              enum nm_config_file_type ncf_type)
 {
        ENTRY;
 
-       lu_object_put(env, &ncf->ncf_obj->do_lu);
+       if (ncf->ncf_obj)
+               lu_object_put(env, &ncf->ncf_obj->do_lu);
 
-       mutex_lock(&ncf_list_lock);
-       list_del(&ncf->ncf_list);
-       mutex_unlock(&ncf_list_lock);
+       if (ncf_type == NCFT_TGT) {
+               mutex_lock(&ncf_list_lock);
+               list_del(&ncf->ncf_list);
+               mutex_unlock(&ncf_list_lock);
+       } else {
+               nodemap_mgs_ncf = NULL;
+       }
        OBD_FREE_PTR(ncf);
 
        EXIT;
 }
 EXPORT_SYMBOL(nm_config_file_deregister);
+
+int nodemap_process_idx_pages(struct nodemap_config *config, union lu_page *lip,
+                             struct lu_nodemap **recent_nodemap)
+{
+       struct nodemap_key *key;
+       union nodemap_rec *rec;
+       char *entry;
+       int j;
+       int k;
+       int rc = 0;
+       int size = dt_nodemap_features.dif_keysize_max +
+                  dt_nodemap_features.dif_recsize_max;
+       ENTRY;
+
+       for (j = 0; j < LU_PAGE_COUNT; j++) {
+               if (lip->lp_idx.lip_magic != LIP_MAGIC)
+                       return -EINVAL;
+
+               /* get and process keys and records from page */
+               for (k = 0; k < lip->lp_idx.lip_nr; k++) {
+                       entry = lip->lp_idx.lip_entries + k * size;
+                       key = (struct nodemap_key *)entry;
+
+                       entry += dt_nodemap_features.dif_keysize_max;
+                       rec = (union nodemap_rec *)entry;
+
+                       rc = nodemap_process_keyrec(config, key, rec,
+                                                   recent_nodemap);
+                       if (rc < 0)
+                               return rc;
+               }
+               lip++;
+       }
+
+       EXIT;
+       return 0;
+}
+EXPORT_SYMBOL(nodemap_process_idx_pages);
+
+int nodemap_index_read(struct lu_env *env,
+                      struct nm_config_file *ncf,
+                      struct idx_info *ii,
+                      const struct lu_rdpg *rdpg)
+{
+       struct dt_object        *nodemap_idx = ncf->ncf_obj;
+       __u64                    version;
+       int                      rc = 0;
+
+       ii->ii_keysize = dt_nodemap_features.dif_keysize_max;
+       ii->ii_recsize = dt_nodemap_features.dif_recsize_max;
+
+       dt_read_lock(env, nodemap_idx, 0);
+       version = dt_version_get(env, nodemap_idx);
+       if (rdpg->rp_hash != 0 && ii->ii_version != version) {
+               CDEBUG(D_INFO, "nodemap config changed while sending, "
+                              "old "LPU64", new "LPU64"\n",
+                      ii->ii_version,
+                      version);
+               ii->ii_hash_end = 0;
+       } else {
+               rc = dt_index_walk(env, nodemap_idx, rdpg, NULL, ii);
+               CDEBUG(D_INFO, "walked index, hashend %llx\n", ii->ii_hash_end);
+       }
+
+       if (rc >= 0)
+               ii->ii_version = version;
+
+       dt_read_unlock(env, nodemap_idx);
+       return rc;
+}
+EXPORT_SYMBOL(nodemap_index_read);
+
+/**
+ * Returns the current nodemap configuration to MGC by walking the nodemap
+ * config index and storing it in the response buffer.
+ *
+ * \param      req             incoming MGS_CONFIG_READ request
+ * \retval     0               success
+ * \retval     -EINVAL         malformed request
+ * \retval     -ENOTCONN       client evicted/reconnected already
+ * \retval     -ETIMEDOUT      client timeout or network error
+ * \retval     -ENOMEM
+ */
+int nodemap_get_config_req(struct obd_device *mgs_obd,
+                          struct ptlrpc_request *req)
+{
+       struct mgs_config_body *body;
+       struct mgs_config_res *res;
+       struct lu_rdpg rdpg;
+       struct idx_info nodemap_ii;
+       struct ptlrpc_bulk_desc *desc;
+       struct l_wait_info lwi;
+       struct tg_export_data *rqexp_ted = &req->rq_export->exp_target_data;
+       int i;
+       int page_count;
+       int bytes = 0;
+       int rc = 0;
+
+       body = req_capsule_client_get(&req->rq_pill, &RMF_MGS_CONFIG_BODY);
+       if (!body)
+               RETURN(-EINVAL);
+
+       if (body->mcb_type != CONFIG_T_NODEMAP)
+               RETURN(-EINVAL);
+
+       rdpg.rp_count = (body->mcb_units << body->mcb_bits);
+       rdpg.rp_npages = (rdpg.rp_count + PAGE_CACHE_SIZE - 1) >>
+               PAGE_CACHE_SHIFT;
+       if (rdpg.rp_npages > PTLRPC_MAX_BRW_PAGES)
+               RETURN(-EINVAL);
+
+       CDEBUG(D_INFO, "reading nodemap log, name '%s', size = %u\n",
+              body->mcb_name, rdpg.rp_count);
+
+       /* allocate pages to store the containers */
+       OBD_ALLOC(rdpg.rp_pages, sizeof(*rdpg.rp_pages) * rdpg.rp_npages);
+       if (rdpg.rp_pages == NULL)
+               RETURN(-ENOMEM);
+       for (i = 0; i < rdpg.rp_npages; i++) {
+               rdpg.rp_pages[i] = alloc_page(GFP_IOFS);
+               if (rdpg.rp_pages[i] == NULL)
+                       GOTO(out, rc = -ENOMEM);
+       }
+
+       rdpg.rp_hash = body->mcb_offset;
+       nodemap_ii.ii_magic = IDX_INFO_MAGIC;
+       nodemap_ii.ii_flags = II_FL_NOHASH;
+       nodemap_ii.ii_version = rqexp_ted->ted_nodemap_version;
+
+       bytes = nodemap_index_read(req->rq_svc_thread->t_env,
+                                  mgs_obd->u.obt.obt_nodemap_config_file,
+                                  &nodemap_ii, &rdpg);
+       if (bytes < 0)
+               GOTO(out, rc = bytes);
+
+       rqexp_ted->ted_nodemap_version = nodemap_ii.ii_version;
+
+       res = req_capsule_server_get(&req->rq_pill, &RMF_MGS_CONFIG_RES);
+       if (res == NULL)
+               GOTO(out, rc = -EINVAL);
+       res->mcr_offset = nodemap_ii.ii_hash_end;
+       res->mcr_size = bytes;
+
+       page_count = (bytes + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+       LASSERT(page_count <= rdpg.rp_count);
+       desc = ptlrpc_prep_bulk_exp(req, page_count, 1,
+                                   PTLRPC_BULK_PUT_SOURCE |
+                                       PTLRPC_BULK_BUF_KIOV,
+                                   MGS_BULK_PORTAL,
+                                   &ptlrpc_bulk_kiov_pin_ops);
+       if (desc == NULL)
+               GOTO(out, rc = -ENOMEM);
+
+       for (i = 0; i < page_count && bytes > 0; i++) {
+               ptlrpc_prep_bulk_page_pin(desc, rdpg.rp_pages[i], 0,
+                                         min_t(int, bytes, PAGE_CACHE_SIZE));
+               bytes -= PAGE_CACHE_SIZE;
+       }
+
+       rc = target_bulk_io(req->rq_export, desc, &lwi);
+       ptlrpc_free_bulk(desc);
+
+out:
+       if (rdpg.rp_pages != NULL) {
+               for (i = 0; i < rdpg.rp_npages; i++)
+                       if (rdpg.rp_pages[i] != NULL)
+                               __free_page(rdpg.rp_pages[i]);
+               OBD_FREE(rdpg.rp_pages,
+                        rdpg.rp_npages * sizeof(rdpg.rp_pages[0]));
+       }
+       return rc;
+}
+EXPORT_SYMBOL(nodemap_get_config_req);