v4.19.13 snapshot.
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
new file mode 100644
index 0000000..8f53455
--- /dev/null
+++ b/fs/nfs/nfs4client.c
@@ -0,0 +1,1277 @@
+/*
+ * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+#include <linux/module.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_mount.h>
+#include <linux/sunrpc/addr.h>
+#include <linux/sunrpc/auth.h>
+#include <linux/sunrpc/xprt.h>
+#include <linux/sunrpc/bc_xprt.h>
+#include <linux/sunrpc/rpc_pipe_fs.h>
+#include "internal.h"
+#include "callback.h"
+#include "delegation.h"
+#include "nfs4session.h"
+#include "nfs4idmap.h"
+#include "pnfs.h"
+#include "netns.h"
+
+#define NFSDBG_FACILITY NFSDBG_CLIENT
+
+/*
+ * Get a unique NFSv4.0 callback identifier which will be used
+ * by the V4.0 callback service to lookup the nfs_client struct
+ */
+static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
+{
+ int ret = 0;
+ struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
+
+ if (clp->rpc_ops->version != 4 || minorversion != 0)
+ return ret;
+ idr_preload(GFP_KERNEL);
+ spin_lock(&nn->nfs_client_lock);
+ ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
+ if (ret >= 0)
+ clp->cl_cb_ident = ret;
+ spin_unlock(&nn->nfs_client_lock);
+ idr_preload_end();
+ return ret < 0 ? ret : 0;
+}
+
+#ifdef CONFIG_NFS_V4_1
+/**
+ * Per auth flavor data server rpc clients
+ */
+struct nfs4_ds_server {
+ struct list_head list; /* ds_clp->cl_ds_clients */
+ struct rpc_clnt *rpc_clnt;
+};
+
+/**
+ * Common lookup case for DS I/O
+ */
+static struct nfs4_ds_server *
+nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
+{
+ struct nfs4_ds_server *dss;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
+ if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
+ continue;
+ goto out;
+ }
+ dss = NULL;
+out:
+ rcu_read_unlock();
+ return dss;
+}
+
+static struct nfs4_ds_server *
+nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
+ struct nfs4_ds_server *new)
+{
+ struct nfs4_ds_server *dss;
+
+ spin_lock(&ds_clp->cl_lock);
+ list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
+ if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
+ continue;
+ goto out;
+ }
+ if (new)
+ list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
+ dss = new;
+out:
+ spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
+ return dss;
+}
+
+static struct nfs4_ds_server *
+nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
+{
+ struct nfs4_ds_server *dss;
+
+ dss = kmalloc(sizeof(*dss), GFP_NOFS);
+ if (dss == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
+ if (IS_ERR(dss->rpc_clnt)) {
+ int err = PTR_ERR(dss->rpc_clnt);
+ kfree (dss);
+ return ERR_PTR(err);
+ }
+ INIT_LIST_HEAD(&dss->list);
+
+ return dss;
+}
+
+static void
+nfs4_free_ds_server(struct nfs4_ds_server *dss)
+{
+ rpc_release_client(dss->rpc_clnt);
+ kfree(dss);
+}
+
+/**
+* Find or create a DS rpc client with th MDS server rpc client auth flavor
+* in the nfs_client cl_ds_clients list.
+*/
+struct rpc_clnt *
+nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
+{
+ struct nfs4_ds_server *dss, *new;
+ rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
+
+ dss = nfs4_find_ds_client(ds_clp, flavor);
+ if (dss != NULL)
+ goto out;
+ new = nfs4_alloc_ds_server(ds_clp, flavor);
+ if (IS_ERR(new))
+ return ERR_CAST(new);
+ dss = nfs4_add_ds_client(ds_clp, flavor, new);
+ if (dss != new)
+ nfs4_free_ds_server(new);
+out:
+ return dss->rpc_clnt;
+}
+EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
+
+static void
+nfs4_shutdown_ds_clients(struct nfs_client *clp)
+{
+ struct nfs4_ds_server *dss;
+ LIST_HEAD(shutdown_list);
+
+ while (!list_empty(&clp->cl_ds_clients)) {
+ dss = list_entry(clp->cl_ds_clients.next,
+ struct nfs4_ds_server, list);
+ list_del(&dss->list);
+ rpc_shutdown_client(dss->rpc_clnt);
+ kfree (dss);
+ }
+}
+
+static void
+nfs4_cleanup_callback(struct nfs_client *clp)
+{
+ struct nfs4_copy_state *cp_state;
+
+ while (!list_empty(&clp->pending_cb_stateids)) {
+ cp_state = list_entry(clp->pending_cb_stateids.next,
+ struct nfs4_copy_state, copies);
+ list_del(&cp_state->copies);
+ kfree(cp_state);
+ }
+}
+
+void nfs41_shutdown_client(struct nfs_client *clp)
+{
+ if (nfs4_has_session(clp)) {
+ nfs4_cleanup_callback(clp);
+ nfs4_shutdown_ds_clients(clp);
+ nfs4_destroy_session(clp->cl_session);
+ nfs4_destroy_clientid(clp);
+ }
+
+}
+#endif /* CONFIG_NFS_V4_1 */
+
+void nfs40_shutdown_client(struct nfs_client *clp)
+{
+ if (clp->cl_slot_tbl) {
+ nfs4_shutdown_slot_table(clp->cl_slot_tbl);
+ kfree(clp->cl_slot_tbl);
+ }
+}
+
+struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
+{
+ int err;
+ struct nfs_client *clp = nfs_alloc_client(cl_init);
+ if (IS_ERR(clp))
+ return clp;
+
+ err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
+ if (err)
+ goto error;
+
+ if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
+ err = -EINVAL;
+ goto error;
+ }
+
+ spin_lock_init(&clp->cl_lock);
+ INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
+ INIT_LIST_HEAD(&clp->cl_ds_clients);
+ rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
+ clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
+ clp->cl_minorversion = cl_init->minorversion;
+ clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
+ clp->cl_mig_gen = 1;
+#if IS_ENABLED(CONFIG_NFS_V4_1)
+ init_waitqueue_head(&clp->cl_lock_waitq);
+#endif
+ INIT_LIST_HEAD(&clp->pending_cb_stateids);
+ return clp;
+
+error:
+ nfs_free_client(clp);
+ return ERR_PTR(err);
+}
+
+/*
+ * Destroy the NFS4 callback service
+ */
+static void nfs4_destroy_callback(struct nfs_client *clp)
+{
+ if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
+ nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
+}
+
+static void nfs4_shutdown_client(struct nfs_client *clp)
+{
+ if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
+ nfs4_kill_renewd(clp);
+ clp->cl_mvops->shutdown_client(clp);
+ nfs4_destroy_callback(clp);
+ if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
+ nfs_idmap_delete(clp);
+
+ rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
+ kfree(clp->cl_serverowner);
+ kfree(clp->cl_serverscope);
+ kfree(clp->cl_implid);
+ kfree(clp->cl_owner_id);
+}
+
+void nfs4_free_client(struct nfs_client *clp)
+{
+ nfs4_shutdown_client(clp);
+ nfs_free_client(clp);
+}
+
+/*
+ * Initialize the NFS4 callback service
+ */
+static int nfs4_init_callback(struct nfs_client *clp)
+{
+ struct rpc_xprt *xprt;
+ int error;
+
+ xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
+
+ if (nfs4_has_session(clp)) {
+ error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
+ if (error < 0)
+ return error;
+ }
+
+ error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
+ if (error < 0) {
+ dprintk("%s: failed to start callback. Error = %d\n",
+ __func__, error);
+ return error;
+ }
+ __set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
+
+ return 0;
+}
+
+/**
+ * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
+ * @clp - nfs_client to initialize
+ *
+ * Returns zero on success, or a negative errno if some error occurred.
+ */
+int nfs40_init_client(struct nfs_client *clp)
+{
+ struct nfs4_slot_table *tbl;
+ int ret;
+
+ tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
+ if (tbl == NULL)
+ return -ENOMEM;
+
+ ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
+ "NFSv4.0 transport Slot table");
+ if (ret) {
+ kfree(tbl);
+ return ret;
+ }
+
+ clp->cl_slot_tbl = tbl;
+ return 0;
+}
+
+#if defined(CONFIG_NFS_V4_1)
+
+/**
+ * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
+ * @clp - nfs_client to initialize
+ *
+ * Returns zero on success, or a negative errno if some error occurred.
+ */
+int nfs41_init_client(struct nfs_client *clp)
+{
+ struct nfs4_session *session = NULL;
+
+ /*
+ * Create the session and mark it expired.
+ * When a SEQUENCE operation encounters the expired session
+ * it will do session recovery to initialize it.
+ */
+ session = nfs4_alloc_session(clp);
+ if (!session)
+ return -ENOMEM;
+
+ clp->cl_session = session;
+
+ /*
+ * The create session reply races with the server back
+ * channel probe. Mark the client NFS_CS_SESSION_INITING
+ * so that the client back channel can find the
+ * nfs_client struct
+ */
+ nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
+ return 0;
+}
+
+#endif /* CONFIG_NFS_V4_1 */
+
+/*
+ * Initialize the minor version specific parts of an NFS4 client record
+ */
+static int nfs4_init_client_minor_version(struct nfs_client *clp)
+{
+ int ret;
+
+ ret = clp->cl_mvops->init_client(clp);
+ if (ret)
+ return ret;
+ return nfs4_init_callback(clp);
+}
+
+/**
+ * nfs4_init_client - Initialise an NFS4 client record
+ *
+ * @clp: nfs_client to initialise
+ * @timeparms: timeout parameters for underlying RPC transport
+ * @ip_addr: callback IP address in presentation format
+ * @authflavor: authentication flavor for underlying RPC transport
+ *
+ * Returns pointer to an NFS client, or an ERR_PTR value.
+ */
+struct nfs_client *nfs4_init_client(struct nfs_client *clp,
+ const struct nfs_client_initdata *cl_init)
+{
+ char buf[INET6_ADDRSTRLEN + 1];
+ const char *ip_addr = cl_init->ip_addr;
+ struct nfs_client *old;
+ int error;
+
+ if (clp->cl_cons_state == NFS_CS_READY)
+ /* the client is initialised already */
+ return clp;
+
+ /* Check NFS protocol revision and initialize RPC op vector */
+ clp->rpc_ops = &nfs_v4_clientops;
+
+ if (clp->cl_minorversion != 0)
+ __set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
+ __set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
+ __set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
+
+ error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
+ if (error == -EINVAL)
+ error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
+ if (error < 0)
+ goto error;
+
+ /* If no clientaddr= option was specified, find a usable cb address */
+ if (ip_addr == NULL) {
+ struct sockaddr_storage cb_addr;
+ struct sockaddr *sap = (struct sockaddr *)&cb_addr;
+
+ error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
+ if (error < 0)
+ goto error;
+ error = rpc_ntop(sap, buf, sizeof(buf));
+ if (error < 0)
+ goto error;
+ ip_addr = (const char *)buf;
+ }
+ strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
+
+ error = nfs_idmap_new(clp);
+ if (error < 0) {
+ dprintk("%s: failed to create idmapper. Error = %d\n",
+ __func__, error);
+ goto error;
+ }
+ __set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
+
+ error = nfs4_init_client_minor_version(clp);
+ if (error < 0)
+ goto error;
+
+ error = nfs4_discover_server_trunking(clp, &old);
+ if (error < 0)
+ goto error;
+
+ if (clp != old) {
+ clp->cl_preserve_clid = true;
+ /*
+ * Mark the client as having failed initialization so other
+ * processes walking the nfs_client_list in nfs_match_client()
+ * won't try to use it.
+ */
+ nfs_mark_client_ready(clp, -EPERM);
+ }
+ nfs_put_client(clp);
+ clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
+ return old;
+
+error:
+ nfs_mark_client_ready(clp, error);
+ nfs_put_client(clp);
+ return ERR_PTR(error);
+}
+
+/*
+ * SETCLIENTID just did a callback update with the callback ident in
+ * "drop," but server trunking discovery claims "drop" and "keep" are
+ * actually the same server. Swap the callback IDs so that "keep"
+ * will continue to use the callback ident the server now knows about,
+ * and so that "keep"'s original callback ident is destroyed when
+ * "drop" is freed.
+ */
+static void nfs4_swap_callback_idents(struct nfs_client *keep,
+ struct nfs_client *drop)
+{
+ struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
+ unsigned int save = keep->cl_cb_ident;
+
+ if (keep->cl_cb_ident == drop->cl_cb_ident)
+ return;
+
+ dprintk("%s: keeping callback ident %u and dropping ident %u\n",
+ __func__, keep->cl_cb_ident, drop->cl_cb_ident);
+
+ spin_lock(&nn->nfs_client_lock);
+
+ idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
+ keep->cl_cb_ident = drop->cl_cb_ident;
+
+ idr_replace(&nn->cb_ident_idr, drop, save);
+ drop->cl_cb_ident = save;
+
+ spin_unlock(&nn->nfs_client_lock);
+}
+
+static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
+ const struct nfs_client *clp2)
+{
+ if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
+ return true;
+ return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
+}
+
+static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
+{
+ return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
+}
+
+static int nfs4_match_client(struct nfs_client *pos, struct nfs_client *new,
+ struct nfs_client **prev, struct nfs_net *nn)
+{
+ int status;
+
+ if (pos->rpc_ops != new->rpc_ops)
+ return 1;
+
+ if (pos->cl_minorversion != new->cl_minorversion)
+ return 1;
+
+ /* If "pos" isn't marked ready, we can't trust the
+ * remaining fields in "pos", especially the client
+ * ID and serverowner fields. Wait for CREATE_SESSION
+ * to finish. */
+ if (pos->cl_cons_state > NFS_CS_READY) {
+ refcount_inc(&pos->cl_count);
+ spin_unlock(&nn->nfs_client_lock);
+
+ nfs_put_client(*prev);
+ *prev = pos;
+
+ status = nfs_wait_client_init_complete(pos);
+ spin_lock(&nn->nfs_client_lock);
+
+ if (status < 0)
+ return status;
+ }
+
+ if (pos->cl_cons_state != NFS_CS_READY)
+ return 1;
+
+ if (pos->cl_clientid != new->cl_clientid)
+ return 1;
+
+ /* NFSv4.1 always uses the uniform string, however someone
+ * might switch the uniquifier string on us.
+ */
+ if (!nfs4_match_client_owner_id(pos, new))
+ return 1;
+
+ return 0;
+}
+
+/**
+ * nfs40_walk_client_list - Find server that recognizes a client ID
+ *
+ * @new: nfs_client with client ID to test
+ * @result: OUT: found nfs_client, or new
+ * @cred: credential to use for trunking test
+ *
+ * Returns zero, a negative errno, or a negative NFS4ERR status.
+ * If zero is returned, an nfs_client pointer is planted in "result."
+ *
+ * NB: nfs40_walk_client_list() relies on the new nfs_client being
+ * the last nfs_client on the list.
+ */
+int nfs40_walk_client_list(struct nfs_client *new,
+ struct nfs_client **result,
+ struct rpc_cred *cred)
+{
+ struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
+ struct nfs_client *pos, *prev = NULL;
+ struct nfs4_setclientid_res clid = {
+ .clientid = new->cl_clientid,
+ .confirm = new->cl_confirm,
+ };
+ int status = -NFS4ERR_STALE_CLIENTID;
+
+ spin_lock(&nn->nfs_client_lock);
+ list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
+
+ if (pos == new)
+ goto found;
+
+ status = nfs4_match_client(pos, new, &prev, nn);
+ if (status < 0)
+ goto out_unlock;
+ if (status != 0)
+ continue;
+ /*
+ * We just sent a new SETCLIENTID, which should have
+ * caused the server to return a new cl_confirm. So if
+ * cl_confirm is the same, then this is a different
+ * server that just returned the same cl_confirm by
+ * coincidence:
+ */
+ if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
+ &new->cl_confirm))
+ continue;
+ /*
+ * But if the cl_confirm's are different, then the only
+ * way that a SETCLIENTID_CONFIRM to pos can succeed is
+ * if new and pos point to the same server:
+ */
+found:
+ refcount_inc(&pos->cl_count);
+ spin_unlock(&nn->nfs_client_lock);
+
+ nfs_put_client(prev);
+ prev = pos;
+
+ status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
+ switch (status) {
+ case -NFS4ERR_STALE_CLIENTID:
+ break;
+ case 0:
+ nfs4_swap_callback_idents(pos, new);
+ pos->cl_confirm = new->cl_confirm;
+ nfs_mark_client_ready(pos, NFS_CS_READY);
+
+ prev = NULL;
+ *result = pos;
+ goto out;
+ case -ERESTARTSYS:
+ case -ETIMEDOUT:
+ /* The callback path may have been inadvertently
+ * changed. Schedule recovery!
+ */
+ nfs4_schedule_path_down_recovery(pos);
+ default:
+ goto out;
+ }
+
+ spin_lock(&nn->nfs_client_lock);
+ }
+out_unlock:
+ spin_unlock(&nn->nfs_client_lock);
+
+ /* No match found. The server lost our clientid */
+out:
+ nfs_put_client(prev);
+ return status;
+}
+
+#ifdef CONFIG_NFS_V4_1
+/*
+ * Returns true if the server major ids match
+ */
+static bool
+nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
+ struct nfs41_server_owner *o2)
+{
+ if (o1->major_id_sz != o2->major_id_sz)
+ return false;
+ return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
+}
+
+/*
+ * Returns true if the server scopes match
+ */
+static bool
+nfs4_check_server_scope(struct nfs41_server_scope *s1,
+ struct nfs41_server_scope *s2)
+{
+ if (s1->server_scope_sz != s2->server_scope_sz)
+ return false;
+ return memcmp(s1->server_scope, s2->server_scope,
+ s1->server_scope_sz) == 0;
+}
+
+/**
+ * nfs4_detect_session_trunking - Checks for session trunking.
+ *
+ * Called after a successful EXCHANGE_ID on a multi-addr connection.
+ * Upon success, add the transport.
+ *
+ * @clp: original mount nfs_client
+ * @res: result structure from an exchange_id using the original mount
+ * nfs_client with a new multi_addr transport
+ *
+ * Returns zero on success, otherwise -EINVAL
+ *
+ * Note: since the exchange_id for the new multi_addr transport uses the
+ * same nfs_client from the original mount, the cl_owner_id is reused,
+ * so eir_clientowner is the same.
+ */
+int nfs4_detect_session_trunking(struct nfs_client *clp,
+ struct nfs41_exchange_id_res *res,
+ struct rpc_xprt *xprt)
+{
+ /* Check eir_clientid */
+ if (clp->cl_clientid != res->clientid)
+ goto out_err;
+
+ /* Check eir_server_owner so_major_id */
+ if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
+ res->server_owner))
+ goto out_err;
+
+ /* Check eir_server_owner so_minor_id */
+ if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
+ goto out_err;
+
+ /* Check eir_server_scope */
+ if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
+ goto out_err;
+
+ pr_info("NFS: %s: Session trunking succeeded for %s\n",
+ clp->cl_hostname,
+ xprt->address_strings[RPC_DISPLAY_ADDR]);
+
+ return 0;
+out_err:
+ pr_info("NFS: %s: Session trunking failed for %s\n", clp->cl_hostname,
+ xprt->address_strings[RPC_DISPLAY_ADDR]);
+
+ return -EINVAL;
+}
+
+/**
+ * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
+ *
+ * @new: nfs_client with client ID to test
+ * @result: OUT: found nfs_client, or new
+ * @cred: credential to use for trunking test
+ *
+ * Returns zero, a negative errno, or a negative NFS4ERR status.
+ * If zero is returned, an nfs_client pointer is planted in "result."
+ *
+ * NB: nfs41_walk_client_list() relies on the new nfs_client being
+ * the last nfs_client on the list.
+ */
+int nfs41_walk_client_list(struct nfs_client *new,
+ struct nfs_client **result,
+ struct rpc_cred *cred)
+{
+ struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
+ struct nfs_client *pos, *prev = NULL;
+ int status = -NFS4ERR_STALE_CLIENTID;
+
+ spin_lock(&nn->nfs_client_lock);
+ list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
+
+ if (pos == new)
+ goto found;
+
+ status = nfs4_match_client(pos, new, &prev, nn);
+ if (status < 0)
+ goto out;
+ if (status != 0)
+ continue;
+
+ /*
+ * Note that session trunking is just a special subcase of
+ * client id trunking. In either case, we want to fall back
+ * to using the existing nfs_client.
+ */
+ if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
+ new->cl_serverowner))
+ continue;
+
+found:
+ refcount_inc(&pos->cl_count);
+ *result = pos;
+ status = 0;
+ break;
+ }
+
+out:
+ spin_unlock(&nn->nfs_client_lock);
+ nfs_put_client(prev);
+ return status;
+}
+#endif /* CONFIG_NFS_V4_1 */
+
+static void nfs4_destroy_server(struct nfs_server *server)
+{
+ nfs_server_return_all_delegations(server);
+ unset_pnfs_layoutdriver(server);
+ nfs4_purge_state_owners(server);
+}
+
+/*
+ * NFSv4.0 callback thread helper
+ *
+ * Find a client by callback identifier
+ */
+struct nfs_client *
+nfs4_find_client_ident(struct net *net, int cb_ident)
+{
+ struct nfs_client *clp;
+ struct nfs_net *nn = net_generic(net, nfs_net_id);
+
+ spin_lock(&nn->nfs_client_lock);
+ clp = idr_find(&nn->cb_ident_idr, cb_ident);
+ if (clp)
+ refcount_inc(&clp->cl_count);
+ spin_unlock(&nn->nfs_client_lock);
+ return clp;
+}
+
+#if defined(CONFIG_NFS_V4_1)
+/* Common match routine for v4.0 and v4.1 callback services */
+static bool nfs4_cb_match_client(const struct sockaddr *addr,
+ struct nfs_client *clp, u32 minorversion)
+{
+ struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
+
+ /* Don't match clients that failed to initialise */
+ if (!(clp->cl_cons_state == NFS_CS_READY ||
+ clp->cl_cons_state == NFS_CS_SESSION_INITING))
+ return false;
+
+ smp_rmb();
+
+ /* Match the version and minorversion */
+ if (clp->rpc_ops->version != 4 ||
+ clp->cl_minorversion != minorversion)
+ return false;
+
+ /* Match only the IP address, not the port number */
+ return rpc_cmp_addr(addr, clap);
+}
+
+/*
+ * NFSv4.1 callback thread helper
+ * For CB_COMPOUND calls, find a client by IP address, protocol version,
+ * minorversion, and sessionID
+ *
+ * Returns NULL if no such client
+ */
+struct nfs_client *
+nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
+ struct nfs4_sessionid *sid, u32 minorversion)
+{
+ struct nfs_client *clp;
+ struct nfs_net *nn = net_generic(net, nfs_net_id);
+
+ spin_lock(&nn->nfs_client_lock);
+ list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
+ if (!nfs4_cb_match_client(addr, clp, minorversion))
+ continue;
+
+ if (!nfs4_has_session(clp))
+ continue;
+
+ /* Match sessionid*/
+ if (memcmp(clp->cl_session->sess_id.data,
+ sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
+ continue;
+
+ refcount_inc(&clp->cl_count);
+ spin_unlock(&nn->nfs_client_lock);
+ return clp;
+ }
+ spin_unlock(&nn->nfs_client_lock);
+ return NULL;
+}
+
+#else /* CONFIG_NFS_V4_1 */
+
+struct nfs_client *
+nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
+ struct nfs4_sessionid *sid, u32 minorversion)
+{
+ return NULL;
+}
+#endif /* CONFIG_NFS_V4_1 */
+
+/*
+ * Set up an NFS4 client
+ */
+static int nfs4_set_client(struct nfs_server *server,
+ const char *hostname,
+ const struct sockaddr *addr,
+ const size_t addrlen,
+ const char *ip_addr,
+ int proto, const struct rpc_timeout *timeparms,
+ u32 minorversion, struct net *net)
+{
+ struct nfs_client_initdata cl_init = {
+ .hostname = hostname,
+ .addr = addr,
+ .addrlen = addrlen,
+ .ip_addr = ip_addr,
+ .nfs_mod = &nfs_v4,
+ .proto = proto,
+ .minorversion = minorversion,
+ .net = net,
+ .timeparms = timeparms,
+ };
+ struct nfs_client *clp;
+
+ if (server->flags & NFS_MOUNT_NORESVPORT)
+ set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
+ if (server->options & NFS_OPTION_MIGRATION)
+ set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
+ if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
+ set_bit(NFS_CS_TSM_POSSIBLE, &cl_init.init_flags);
+ server->port = rpc_get_port(addr);
+
+ /* Allocate or find a client reference we can use */
+ clp = nfs_get_client(&cl_init);
+ if (IS_ERR(clp))
+ return PTR_ERR(clp);
+
+ if (server->nfs_client == clp) {
+ nfs_put_client(clp);
+ return -ELOOP;
+ }
+
+ /*
+ * Query for the lease time on clientid setup or renewal
+ *
+ * Note that this will be set on nfs_clients that were created
+ * only for the DS role and did not set this bit, but now will
+ * serve a dual role.
+ */
+ set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
+
+ server->nfs_client = clp;
+ return 0;
+}
+
+/*
+ * Set up a pNFS Data Server client.
+ *
+ * Return any existing nfs_client that matches server address,port,version
+ * and minorversion.
+ *
+ * For a new nfs_client, use a soft mount (default), a low retrans and a
+ * low timeout interval so that if a connection is lost, we retry through
+ * the MDS.
+ */
+struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
+ const struct sockaddr *ds_addr, int ds_addrlen,
+ int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
+ u32 minor_version)
+{
+ struct rpc_timeout ds_timeout;
+ struct nfs_client *mds_clp = mds_srv->nfs_client;
+ struct nfs_client_initdata cl_init = {
+ .addr = ds_addr,
+ .addrlen = ds_addrlen,
+ .nodename = mds_clp->cl_rpcclient->cl_nodename,
+ .ip_addr = mds_clp->cl_ipaddr,
+ .nfs_mod = &nfs_v4,
+ .proto = ds_proto,
+ .minorversion = minor_version,
+ .net = mds_clp->cl_net,
+ .timeparms = &ds_timeout,
+ };
+ char buf[INET6_ADDRSTRLEN + 1];
+
+ if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
+ return ERR_PTR(-EINVAL);
+ cl_init.hostname = buf;
+
+ if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
+ __set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
+
+ /*
+ * Set an authflavor equual to the MDS value. Use the MDS nfs_client
+ * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
+ * (section 13.1 RFC 5661).
+ */
+ nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
+ return nfs_get_client(&cl_init);
+}
+EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
+
+/*
+ * Session has been established, and the client marked ready.
+ * Limit the mount rsize, wsize and dtsize using negotiated fore
+ * channel attributes.
+ */
+static void nfs4_session_limit_rwsize(struct nfs_server *server)
+{
+#ifdef CONFIG_NFS_V4_1
+ struct nfs4_session *sess;
+ u32 server_resp_sz;
+ u32 server_rqst_sz;
+
+ if (!nfs4_has_session(server->nfs_client))
+ return;
+ sess = server->nfs_client->cl_session;
+ server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
+ server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
+
+ if (server->dtsize > server_resp_sz)
+ server->dtsize = server_resp_sz;
+ if (server->rsize > server_resp_sz)
+ server->rsize = server_resp_sz;
+ if (server->wsize > server_rqst_sz)
+ server->wsize = server_rqst_sz;
+#endif /* CONFIG_NFS_V4_1 */
+}
+
+static int nfs4_server_common_setup(struct nfs_server *server,
+ struct nfs_fh *mntfh, bool auth_probe)
+{
+ struct nfs_fattr *fattr;
+ int error;
+
+ /* data servers support only a subset of NFSv4.1 */
+ if (is_ds_only_client(server->nfs_client))
+ return -EPROTONOSUPPORT;
+
+ fattr = nfs_alloc_fattr();
+ if (fattr == NULL)
+ return -ENOMEM;
+
+ /* We must ensure the session is initialised first */
+ error = nfs4_init_session(server->nfs_client);
+ if (error < 0)
+ goto out;
+
+ /* Set the basic capabilities */
+ server->caps |= server->nfs_client->cl_mvops->init_caps;
+ if (server->flags & NFS_MOUNT_NORDIRPLUS)
+ server->caps &= ~NFS_CAP_READDIRPLUS;
+ /*
+ * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
+ * authentication.
+ */
+ if (nfs4_disable_idmapping &&
+ server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
+ server->caps |= NFS_CAP_UIDGID_NOMAP;
+
+
+ /* Probe the root fh to retrieve its FSID and filehandle */
+ error = nfs4_get_rootfh(server, mntfh, auth_probe);
+ if (error < 0)
+ goto out;
+
+ dprintk("Server FSID: %llx:%llx\n",
+ (unsigned long long) server->fsid.major,
+ (unsigned long long) server->fsid.minor);
+ nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
+
+ error = nfs_probe_fsinfo(server, mntfh, fattr);
+ if (error < 0)
+ goto out;
+
+ nfs4_session_limit_rwsize(server);
+
+ if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
+ server->namelen = NFS4_MAXNAMLEN;
+
+ nfs_server_insert_lists(server);
+ server->mount_time = jiffies;
+ server->destroy = nfs4_destroy_server;
+out:
+ nfs_free_fattr(fattr);
+ return error;
+}
+
+/*
+ * Create a version 4 volume record
+ */
+static int nfs4_init_server(struct nfs_server *server,
+ struct nfs_parsed_mount_data *data)
+{
+ struct rpc_timeout timeparms;
+ int error;
+
+ nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
+ data->timeo, data->retrans);
+
+ /* Initialise the client representation from the mount data */
+ server->flags = data->flags;
+ server->options = data->options;
+ server->auth_info = data->auth_info;
+
+ /* Use the first specified auth flavor. If this flavor isn't
+ * allowed by the server, use the SECINFO path to try the
+ * other specified flavors */
+ if (data->auth_info.flavor_len >= 1)
+ data->selected_flavor = data->auth_info.flavors[0];
+ else
+ data->selected_flavor = RPC_AUTH_UNIX;
+
+ /* Get a client record */
+ error = nfs4_set_client(server,
+ data->nfs_server.hostname,
+ (const struct sockaddr *)&data->nfs_server.address,
+ data->nfs_server.addrlen,
+ data->client_address,
+ data->nfs_server.protocol,
+ &timeparms,
+ data->minorversion,
+ data->net);
+ if (error < 0)
+ return error;
+
+ if (data->rsize)
+ server->rsize = nfs_block_size(data->rsize, NULL);
+ if (data->wsize)
+ server->wsize = nfs_block_size(data->wsize, NULL);
+
+ server->acregmin = data->acregmin * HZ;
+ server->acregmax = data->acregmax * HZ;
+ server->acdirmin = data->acdirmin * HZ;
+ server->acdirmax = data->acdirmax * HZ;
+ server->port = data->nfs_server.port;
+
+ return nfs_init_server_rpcclient(server, &timeparms,
+ data->selected_flavor);
+}
+
+/*
+ * Create a version 4 volume record
+ * - keyed on server and FSID
+ */
+/*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
+ struct nfs_fh *mntfh)*/
+struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
+ struct nfs_subversion *nfs_mod)
+{
+ struct nfs_server *server;
+ bool auth_probe;
+ int error;
+
+ server = nfs_alloc_server();
+ if (!server)
+ return ERR_PTR(-ENOMEM);
+
+ auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
+
+ /* set up the general RPC client */
+ error = nfs4_init_server(server, mount_info->parsed);
+ if (error < 0)
+ goto error;
+
+ error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
+ if (error < 0)
+ goto error;
+
+ return server;
+
+error:
+ nfs_free_server(server);
+ return ERR_PTR(error);
+}
+
+/*
+ * Create an NFS4 referral server record
+ */
+struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
+ struct nfs_fh *mntfh)
+{
+ struct nfs_client *parent_client;
+ struct nfs_server *server, *parent_server;
+ bool auth_probe;
+ int error;
+
+ server = nfs_alloc_server();
+ if (!server)
+ return ERR_PTR(-ENOMEM);
+
+ parent_server = NFS_SB(data->sb);
+ parent_client = parent_server->nfs_client;
+
+ /* Initialise the client representation from the parent server */
+ nfs_server_copy_userdata(server, parent_server);
+
+ /* Get a client representation */
+#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
+ rpc_set_port(data->addr, NFS_RDMA_PORT);
+ error = nfs4_set_client(server, data->hostname,
+ data->addr,
+ data->addrlen,
+ parent_client->cl_ipaddr,
+ XPRT_TRANSPORT_RDMA,
+ parent_server->client->cl_timeout,
+ parent_client->cl_mvops->minor_version,
+ parent_client->cl_net);
+ if (!error)
+ goto init_server;
+#endif /* IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA) */
+
+ rpc_set_port(data->addr, NFS_PORT);
+ error = nfs4_set_client(server, data->hostname,
+ data->addr,
+ data->addrlen,
+ parent_client->cl_ipaddr,
+ XPRT_TRANSPORT_TCP,
+ parent_server->client->cl_timeout,
+ parent_client->cl_mvops->minor_version,
+ parent_client->cl_net);
+ if (error < 0)
+ goto error;
+
+#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
+init_server:
+#endif
+ error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
+ if (error < 0)
+ goto error;
+
+ auth_probe = parent_server->auth_info.flavor_len < 1;
+
+ error = nfs4_server_common_setup(server, mntfh, auth_probe);
+ if (error < 0)
+ goto error;
+
+ return server;
+
+error:
+ nfs_free_server(server);
+ return ERR_PTR(error);
+}
+
+/*
+ * Grab the destination's particulars, including lease expiry time.
+ *
+ * Returns zero if probe succeeded and retrieved FSID matches the FSID
+ * we have cached.
+ */
+static int nfs_probe_destination(struct nfs_server *server)
+{
+ struct inode *inode = d_inode(server->super->s_root);
+ struct nfs_fattr *fattr;
+ int error;
+
+ fattr = nfs_alloc_fattr();
+ if (fattr == NULL)
+ return -ENOMEM;
+
+ /* Sanity: the probe won't work if the destination server
+ * does not recognize the migrated FH. */
+ error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
+
+ nfs_free_fattr(fattr);
+ return error;
+}
+
+/**
+ * nfs4_update_server - Move an nfs_server to a different nfs_client
+ *
+ * @server: represents FSID to be moved
+ * @hostname: new end-point's hostname
+ * @sap: new end-point's socket address
+ * @salen: size of "sap"
+ * @net: net namespace
+ *
+ * The nfs_server must be quiescent before this function is invoked.
+ * Either its session is drained (NFSv4.1+), or its transport is
+ * plugged and drained (NFSv4.0).
+ *
+ * Returns zero on success, or a negative errno value.
+ */
+int nfs4_update_server(struct nfs_server *server, const char *hostname,
+ struct sockaddr *sap, size_t salen, struct net *net)
+{
+ struct nfs_client *clp = server->nfs_client;
+ struct rpc_clnt *clnt = server->client;
+ struct xprt_create xargs = {
+ .ident = clp->cl_proto,
+ .net = net,
+ .dstaddr = sap,
+ .addrlen = salen,
+ .servername = hostname,
+ };
+ char buf[INET6_ADDRSTRLEN + 1];
+ struct sockaddr_storage address;
+ struct sockaddr *localaddr = (struct sockaddr *)&address;
+ int error;
+
+ error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
+ if (error != 0)
+ return error;
+
+ error = rpc_localaddr(clnt, localaddr, sizeof(address));
+ if (error != 0)
+ return error;
+
+ if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
+ return -EAFNOSUPPORT;
+
+ nfs_server_remove_lists(server);
+ set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
+ error = nfs4_set_client(server, hostname, sap, salen, buf,
+ clp->cl_proto, clnt->cl_timeout,
+ clp->cl_minorversion, net);
+ clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
+ if (error != 0) {
+ nfs_server_insert_lists(server);
+ return error;
+ }
+ nfs_put_client(clp);
+
+ if (server->nfs_client->cl_hostname == NULL)
+ server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
+ nfs_server_insert_lists(server);
+
+ return nfs_probe_destination(server);
+}