nfsd: make NFSd service structure allocated per net

This patch makes main step in NFSd containerisation.

There could be different approaches to how to make NFSd able to handle
incoming RPC request from different network namespaces.  The two main
options are:

1) Share NFSd kthreads betwween all network namespaces.
2) Create separated pool of threads for each namespace.

While first approach looks more flexible, second one is simpler and
non-racy.  This patch implements the second option.

To make it possible to allocate separate pools of threads, we have to
make it possible to allocate separate NFSd service structures per net.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 4 insertions, 14 deletions

diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index 71ba60d36234..de23db255c69 100644
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -55,7 +55,6 @@ extern struct svc_version	nfsd_version2, nfsd_version3,
                                 nfsd_version4;
 extern u32                      nfsd_supported_minorversion;
 extern struct mutex             nfsd_mutex;
-extern struct svc_serv          *nfsd_serv;
 extern spinlock_t               nfsd_drc_lock;
 extern unsigned int             nfsd_drc_max_mem;
 extern unsigned int             nfsd_drc_mem_used;
@@ -68,23 +67,14 @@ extern const struct seq_operations nfs_exports_op;
 int             nfsd_svc(int nrservs, struct net *net);
 int             nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp);
 
-int             nfsd_nrthreads(void);
-int             nfsd_nrpools(void);
-int             nfsd_get_nrthreads(int n, int *);
+int             nfsd_nrthreads(struct net *);
+int             nfsd_nrpools(struct net *);
+int             nfsd_get_nrthreads(int n, int *, struct net *);
 int             nfsd_set_nrthreads(int n, int *, struct net *);
 int             nfsd_pool_stats_open(struct inode *, struct file *);
 int             nfsd_pool_stats_release(struct inode *, struct file *);
 
-static inline void nfsd_destroy(struct net *net)
-{
-        int destroy = (nfsd_serv->sv_nrthreads == 1);
-
-        if (destroy)
-                svc_shutdown_net(nfsd_serv, net);
-        svc_destroy(nfsd_serv);
-        if (destroy)
-                nfsd_serv = NULL;
-}
+void            nfsd_destroy(struct net *net);
 
 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
 #ifdef CONFIG_NFSD_V2_ACL