[PATCH] nfsd: have __write_ports_add/delxprt get/put lockd references for transports

From: Jeff Layton
Date: Thu Jun 17 2010 - 10:22:33 EST


nfsd_last_thread expects that any socket on sv_permsocks will hold a
lockd reference. Make sure that __write_ports_addxprt takes a lockd
reference for each socket it creates and have __write_ports_delxprt
release references when it closes a socket.

Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/nfsd/nfsctl.c | 59 ++++++++++++++++++++++++++++++++++++++---------------
1 files changed, 42 insertions(+), 17 deletions(-)

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 9e8645a..365aee0 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -989,6 +989,21 @@ static ssize_t __write_ports_delfd(char *buf)
return len;
}

+static int
+nfsd_shutdown_xprt(const char *transport, const unsigned short family,
+ const int port)
+{
+ struct svc_xprt *xprt;
+
+ xprt = svc_find_xprt(nfsd_serv, transport, family, port);
+ if (xprt == NULL)
+ return -ENOTCONN;
+
+ svc_close_xprt(xprt);
+ svc_xprt_put(xprt);
+ return 0;
+}
+
/*
* A transport listener is added by writing it's transport name and
* a port number.
@@ -996,7 +1011,6 @@ static ssize_t __write_ports_delfd(char *buf)
static ssize_t __write_ports_addxprt(char *buf)
{
char transport[16];
- struct svc_xprt *xprt;
int port, err;

if (sscanf(buf, "%15s %4u", transport, &port) != 2)
@@ -1014,20 +1028,29 @@ static ssize_t __write_ports_addxprt(char *buf)
if (err < 0)
goto out_err;

+ err = lockd_up();
+ if (err != 0) {
+ nfsd_shutdown_xprt(transport, PF_INET, port);
+ goto out_err;
+ }
+
err = svc_create_xprt(nfsd_serv, transport,
PF_INET6, port, SVC_SOCK_ANONYMOUS);
- if (err < 0 && err != -EAFNOSUPPORT)
- goto out_close;
+ if (err < 0 && err != -EAFNOSUPPORT) {
+ nfsd_shutdown_xprt(transport, PF_INET, port);
+ goto out_err;
+ }
+
+ err = lockd_up();
+ if (err != 0) {
+ nfsd_shutdown_xprt(transport, PF_INET6, port);
+ nfsd_shutdown_xprt(transport, PF_INET, port);
+ goto out_err;
+ }

/* Decrease the count, but don't shut down the service */
nfsd_serv->sv_nrthreads--;
return 0;
-out_close:
- xprt = svc_find_xprt(nfsd_serv, transport, PF_INET, port);
- if (xprt != NULL) {
- svc_close_xprt(xprt);
- svc_xprt_put(xprt);
- }
out_err:
svc_destroy(nfsd_serv);
return err;
@@ -1039,9 +1062,8 @@ out_err:
*/
static ssize_t __write_ports_delxprt(char *buf)
{
- struct svc_xprt *xprt;
char transport[16];
- int port;
+ int port, err;

if (sscanf(&buf[1], "%15s %4u", transport, &port) != 2)
return -EINVAL;
@@ -1049,13 +1071,16 @@ static ssize_t __write_ports_delxprt(char *buf)
if (port < 1 || port > USHRT_MAX || nfsd_serv == NULL)
return -EINVAL;

- xprt = svc_find_xprt(nfsd_serv, transport, AF_UNSPEC, port);
- if (xprt == NULL)
- return -ENOTCONN;
+ /* PF_INET6 sockets are considered optional */
+ err = nfsd_shutdown_xprt(transport, PF_INET6, port);
+ if (err == 0)
+ lockd_down();

- svc_close_xprt(xprt);
- svc_xprt_put(xprt);
- return 0;
+ err = nfsd_shutdown_xprt(transport, PF_INET, port);
+ if (err == 0)
+ lockd_down();
+
+ return err;
}

static ssize_t __write_ports(struct file *file, char *buf, size_t size)
--
1.5.5.6

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