NFS/pnfs: Separate NFSv3 DS and MDS traffic
If a NFSv3 server is being used as both a DS and as a regular NFSv3 server,
we may want to keep the IO traffic on a separate TCP connection, since
it will typically have very different timeout characteristics.
This patch therefore sets up a flag to separate the two modes of operation
for the nfs_client.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index fa7d923..bd6575e 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -312,6 +312,12 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat
/* Match nfsv4 minorversion */
if (clp->cl_minorversion != data->minorversion)
continue;
+
+ /* Match request for a dedicated DS */
+ if (test_bit(NFS_CS_DS, &data->init_flags) !=
+ test_bit(NFS_CS_DS, &clp->cl_flags))
+ continue;
+
/* Match the full socket address */
if (!rpc_cmp_addr_port(sap, clap))
/* Match all xprt_switch full socket addresses */
diff --git a/fs/nfs/nfs3client.c b/fs/nfs/nfs3client.c
index 793fa42..223904b 100644
--- a/fs/nfs/nfs3client.c
+++ b/fs/nfs/nfs3client.c
@@ -109,6 +109,7 @@ struct nfs_client *nfs3_set_ds_client(struct nfs_server *mds_srv,
__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
__set_bit(NFS_CS_NOPING, &cl_init.init_flags);
+ __set_bit(NFS_CS_DS, &cl_init.init_flags);
/* Use the MDS nfs_client cl_ipaddr. */
nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index a50dd43..69e80ce 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -46,6 +46,7 @@ struct nfs_client {
#define NFS_CS_NO_RETRANS_TIMEOUT 4 /* - Disable retransmit timeouts */
#define NFS_CS_TSM_POSSIBLE 5 /* - Maybe state migration */
#define NFS_CS_NOPING 6 /* - don't ping on connect */
+#define NFS_CS_DS 7 /* - Server is a DS */
struct sockaddr_storage cl_addr; /* server identifier */
size_t cl_addrlen;
char * cl_hostname; /* hostname of server */
