NFS: Add basic migration support to state manager thread
Migration recovery and state recovery must be serialized, so handle
both in the state manager thread.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index e59d3b4..94e783f 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -29,6 +29,7 @@
NFS4CLNT_SERVER_SCOPE_MISMATCH,
NFS4CLNT_PURGE_STATE,
NFS4CLNT_BIND_CONN_TO_SESSION,
+ NFS4CLNT_MOVED,
};
#define NFS4_RENEW_TIMEOUT 0x01
@@ -421,6 +422,7 @@
extern void nfs4_schedule_state_manager(struct nfs_client *);
extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
+extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);
extern void nfs41_handle_server_scope(struct nfs_client *,
struct nfs41_server_scope **);
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
index a2cba66..0cde95e 100644
--- a/fs/nfs/nfs4client.c
+++ b/fs/nfs/nfs4client.c
@@ -197,6 +197,7 @@
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;
return clp;
error:
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index fa2706a..ba0db18 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -239,8 +239,6 @@
}
}
-#if defined(CONFIG_NFS_V4_1)
-
static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
{
set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
@@ -270,6 +268,8 @@
return nfs4_drain_slot_tbl(&ses->fc_slot_table);
}
+#if defined(CONFIG_NFS_V4_1)
+
static int nfs41_setup_state_renewal(struct nfs_client *clp)
{
int status;
@@ -1197,6 +1197,42 @@
}
EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
+/**
+ * nfs4_schedule_migration_recovery - trigger migration recovery
+ *
+ * @server: FSID that is migrating
+ *
+ * Returns zero if recovery has started, otherwise a negative NFS4ERR
+ * value is returned.
+ */
+int nfs4_schedule_migration_recovery(const struct nfs_server *server)
+{
+ struct nfs_client *clp = server->nfs_client;
+
+ if (server->fh_expire_type != NFS4_FH_PERSISTENT) {
+ pr_err("NFS: volatile file handles not supported (server %s)\n",
+ clp->cl_hostname);
+ return -NFS4ERR_IO;
+ }
+
+ if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+ return -NFS4ERR_IO;
+
+ dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n",
+ __func__,
+ (unsigned long long)server->fsid.major,
+ (unsigned long long)server->fsid.minor,
+ clp->cl_hostname);
+
+ set_bit(NFS_MIG_IN_TRANSITION,
+ &((struct nfs_server *)server)->mig_status);
+ set_bit(NFS4CLNT_MOVED, &clp->cl_state);
+
+ nfs4_schedule_state_manager(clp);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
+
int nfs4_wait_clnt_recover(struct nfs_client *clp)
{
int res;
@@ -1826,6 +1862,119 @@
return 0;
}
+/*
+ * Try remote migration of one FSID from a source server to a
+ * destination server. The source server provides a list of
+ * potential destinations.
+ *
+ * Returns zero or a negative NFS4ERR status code.
+ */
+static int nfs4_try_migration(struct nfs_server *server, struct rpc_cred *cred)
+{
+ struct nfs_client *clp = server->nfs_client;
+ struct nfs4_fs_locations *locations = NULL;
+ struct inode *inode;
+ struct page *page;
+ int status, result;
+
+ dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__,
+ (unsigned long long)server->fsid.major,
+ (unsigned long long)server->fsid.minor,
+ clp->cl_hostname);
+
+ result = 0;
+ page = alloc_page(GFP_KERNEL);
+ locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
+ if (page == NULL || locations == NULL) {
+ dprintk("<-- %s: no memory\n", __func__);
+ goto out;
+ }
+
+ inode = server->super->s_root->d_inode;
+ result = nfs4_proc_get_locations(inode, locations, page, cred);
+ if (result) {
+ dprintk("<-- %s: failed to retrieve fs_locations: %d\n",
+ __func__, result);
+ goto out;
+ }
+
+ result = -NFS4ERR_NXIO;
+ if (!(locations->fattr.valid & NFS_ATTR_FATTR_V4_LOCATIONS)) {
+ dprintk("<-- %s: No fs_locations data, migration skipped\n",
+ __func__);
+ goto out;
+ }
+
+ nfs4_begin_drain_session(clp);
+
+ status = nfs4_replace_transport(server, locations);
+ if (status != 0) {
+ dprintk("<-- %s: failed to replace transport: %d\n",
+ __func__, status);
+ goto out;
+ }
+
+ result = 0;
+ dprintk("<-- %s: migration succeeded\n", __func__);
+
+out:
+ if (page != NULL)
+ __free_page(page);
+ kfree(locations);
+ if (result) {
+ pr_err("NFS: migration recovery failed (server %s)\n",
+ clp->cl_hostname);
+ set_bit(NFS_MIG_FAILED, &server->mig_status);
+ }
+ return result;
+}
+
+/*
+ * Returns zero or a negative NFS4ERR status code.
+ */
+static int nfs4_handle_migration(struct nfs_client *clp)
+{
+ const struct nfs4_state_maintenance_ops *ops =
+ clp->cl_mvops->state_renewal_ops;
+ struct nfs_server *server;
+ struct rpc_cred *cred;
+
+ dprintk("%s: migration reported on \"%s\"\n", __func__,
+ clp->cl_hostname);
+
+ spin_lock(&clp->cl_lock);
+ cred = ops->get_state_renewal_cred_locked(clp);
+ spin_unlock(&clp->cl_lock);
+ if (cred == NULL)
+ return -NFS4ERR_NOENT;
+
+ clp->cl_mig_gen++;
+restart:
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ int status;
+
+ if (server->mig_gen == clp->cl_mig_gen)
+ continue;
+ server->mig_gen = clp->cl_mig_gen;
+
+ if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION,
+ &server->mig_status))
+ continue;
+
+ rcu_read_unlock();
+ status = nfs4_try_migration(server, cred);
+ if (status < 0) {
+ put_rpccred(cred);
+ return status;
+ }
+ goto restart;
+ }
+ rcu_read_unlock();
+ put_rpccred(cred);
+ return 0;
+}
+
/**
* nfs4_discover_server_trunking - Detect server IP address trunking
*
@@ -2154,7 +2303,13 @@
status = nfs4_check_lease(clp);
if (status < 0)
goto out_error;
- continue;
+ }
+
+ if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) {
+ section = "migration";
+ status = nfs4_handle_migration(clp);
+ if (status < 0)
+ goto out_error;
}
/* First recover reboot state... */
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 46b0cb4..186ec49 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -79,6 +79,7 @@
char cl_ipaddr[48];
u32 cl_cb_ident; /* v4.0 callback identifier */
const struct nfs4_minor_version_ops *cl_mvops;
+ unsigned long cl_mig_gen;
/* NFSv4.0 transport blocking */
struct nfs4_slot_table *cl_slot_tbl;
@@ -189,6 +190,12 @@
struct list_head state_owners_lru;
struct list_head layouts;
struct list_head delegations;
+
+ unsigned long mig_gen;
+ unsigned long mig_status;
+#define NFS_MIG_IN_TRANSITION (1)
+#define NFS_MIG_FAILED (2)
+
void (*destroy)(struct nfs_server *);
atomic_t active; /* Keep trace of any activity to this server */