Now that the refcounting is fixed, rework nfsd_svc to use the same
thread setup as the pool_threads interface. Have it take an array of
thread counts instead of just a single value, and pass that from the
netlink threads set interface. Since the new netlink interface doesn't
have the same restriction as pool_threads, move the guard against
shutting down all threads to write_pool_threads.
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/nfsd/nfsctl.c | 12 ++++++++++--
fs/nfsd/nfsd.h | 3 ++-
fs/nfsd/nfssvc.c | 47 ++++++++++++++++++++++++++---------------------
3 files changed, 38 insertions(+), 24 deletions(-)
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 202140df8f82..c0d84a6e5416 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -406,7 +406,7 @@ static ssize_t write_threads(struct file *file, char *buf, size_t size)
return -EINVAL;
trace_nfsd_ctl_threads(net, newthreads);
mutex_lock(&nfsd_mutex);
- rv = nfsd_svc(newthreads, net, file->f_cred, NULL);
+ rv = nfsd_svc(1, &newthreads, net, file->f_cred, NULL);
mutex_unlock(&nfsd_mutex);
if (rv < 0)
return rv;
@@ -481,6 +481,14 @@ static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
goto out_free;
trace_nfsd_ctl_pool_threads(net, i, nthreads[i]);
}
+
+ /*
+ * There must always be a thread in pool 0; the admin
+ * can't shut down NFS completely using pool_threads.
+ */
+ if (nthreads[0] == 0)
+ nthreads[0] = 1;
+
rv = nfsd_set_nrthreads(i, nthreads, net);
if (rv)
goto out_free;
@@ -1722,7 +1730,7 @@ int nfsd_nl_threads_set_doit(struct sk_buff *skb, struct genl_info *info)
scope = nla_data(attr);
}
- ret = nfsd_svc(nthreads, net, get_current_cred(), scope);
+ ret = nfsd_svc(1, &nthreads, net, get_current_cred(), scope);
out_unlock:
mutex_unlock(&nfsd_mutex);
diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index 8f4f239d9f8a..cec8697b1cd6 100644
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -103,7 +103,8 @@ bool nfssvc_encode_voidres(struct svc_rqst *rqstp,
/*
* Function prototypes.
*/
-int nfsd_svc(int nrservs, struct net *net, const struct cred *cred, const char *scope);
+int nfsd_svc(int n, int *nservers, struct net *net,
+ const struct cred *cred, const char *scope);
int nfsd_dispatch(struct svc_rqst *rqstp);
int nfsd_nrthreads(struct net *);
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index cd9a6a1a9fc8..2e47fd26c9b4 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -710,6 +710,19 @@ int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
return 0;
}
+/**
+ * nfsd_set_nrthreads - set the number of running threads in the net's service
+ * @n: number of array members in @nthreads
+ * @nthreads: array of thread counts for each pool
+ * @net: network namespace to operate within
+ *
+ * This function alters the number of running threads for the given network
+ * namespace in each pool. If passed an array longer then the number of pools
+ * the extra pool settings are ignored. If passed an array shorter than the
+ * number of pools, the missing values are interpreted as 0's.
+ *
+ * Returns 0 on success or a negative errno on error.
+ */
int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
{
int i = 0;
@@ -717,7 +730,7 @@ int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
int err = 0;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
- WARN_ON(!mutex_is_locked(&nfsd_mutex));
+ lockdep_assert_held(&nfsd_mutex);
if (nn->nfsd_serv == NULL || n <= 0)
return 0;
@@ -744,13 +757,6 @@ int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
}
}
- /*
- * There must always be a thread in pool 0; the admin
- * can't shut down NFS completely using pool_threads.
- */
- if (nthreads[0] == 0)
- nthreads[0] = 1;
-
/* apply the new numbers */
for (i = 0; i < n; i++) {
err = svc_set_num_threads(nn->nfsd_serv,
@@ -762,13 +768,19 @@ int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
return err;
}
-/*
- * Adjust the number of threads and return the new number of threads.
- * This is also the function that starts the server if necessary, if
- * this is the first time nrservs is nonzero.
+/**
+ * nfsd_svc: start up or shut down the nfsd server
+ * @n: number of array members in @nthreads
+ * @nthreads: array of thread counts for each pool
+ * @net: network namespace to operate within
+ * @cred: credentials to use for xprt creation
+ * @scope: server scope value (defaults to nodename)
+ *
+ * Adjust the number of threads in each pool and return the new
+ * total number of threads in the service.
*/
int
-nfsd_svc(int nrservs, struct net *net, const struct cred *cred, const char *scope)
+nfsd_svc(int n, int *nthreads, struct net *net, const struct cred *cred, const char *scope)
{
int error;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
@@ -778,13 +790,6 @@ nfsd_svc(int nrservs, struct net *net, const struct cred *cred, const char *scop
dprintk("nfsd: creating service\n");
- nrservs = max(nrservs, 0);
- nrservs = min(nrservs, NFSD_MAXSERVS);
- error = 0;
-
- if (nrservs == 0 && nn->nfsd_serv == NULL)
- goto out;
-
strscpy(nn->nfsd_name, scope ? scope : utsname()->nodename,
sizeof(nn->nfsd_name));
@@ -796,7 +801,7 @@ nfsd_svc(int nrservs, struct net *net, const struct cred *cred, const char *scop
error = nfsd_startup_net(net, cred);
if (error)
goto out_put;
- error = svc_set_num_threads(serv, NULL, nrservs);
+ error = nfsd_set_nrthreads(n, nthreads, net);
if (error)
goto out_put;
error = serv->sv_nrthreads;
--
2.45.2
