[PATCH v3 5/8] nfs: remove sv_bc_enabled using in svc_is_backchannel()

Vasily Averin
2018-12-21T17:35:54Z

serv->sv_bc_xprt cannot be used as pointer,
serv is global structure, but sv_bc_xprt is assigned per-netnamespace.

The only user of this field is svc_is_backchannel() where it is used
not as pointer but as mark of backchannel-compatible servers.

Convert netns-unsafe xprt pointer to simple boolean mark.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
---
include/linux/sunrpc/bc_xprt.h | 10 ++++------
include/linux/sunrpc/svc.h | 2 +-
net/sunrpc/svcsock.c | 2 +-
net/sunrpc/xprtrdma/svc_rdma_transport.c | 2 +-
4 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/include/linux/sunrpc/bc_xprt.h b/include/linux/sunrpc/bc_xprt.h
index 28721cf73ec3..4e8c773d02be 100644
--- a/include/linux/sunrpc/bc_xprt.h
+++ b/include/linux/sunrpc/bc_xprt.h
@@ -47,11 +47,9 @@ void xprt_free_bc_rqst(struct rpc_rqst *req);
/*
* Determine if a shared backchannel is in use
*/
-static inline int svc_is_backchannel(const struct svc_rqst *rqstp)
+static inline bool svc_is_backchannel(const struct svc_rqst *rqstp)
{
- if (rqstp->rq_server->sv_bc_xprt)
- return 1;
- return 0;
+ return rqstp->rq_server->sv_bc_enabled;
}
#else /* CONFIG_SUNRPC_BACKCHANNEL */
static inline int xprt_setup_backchannel(struct rpc_xprt *xprt,
@@ -60,9 +58,9 @@ static inline int xprt_setup_backchannel(struct rpc_xprt *xprt,
return 0;
}

-static inline int svc_is_backchannel(const struct svc_rqst *rqstp)
+static inline bool svc_is_backchannel(const struct svc_rqst *rqstp)
{
- return 0;
+ return false;
}

static inline void xprt_free_bc_request(struct rpc_rqst *req)
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 670596f4fdf7..8162d67d121f 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -109,7 +109,7 @@ struct svc_serv {
spinlock_t sv_cb_lock; /* protects the svc_cb_list */
wait_queue_head_t sv_cb_waitq; /* sleep here if there are no
* entries in the svc_cb_list */
- struct svc_xprt *sv_bc_xprt; /* callback on fore channel */
+ bool sv_bc_enabled; /* server uses backchannel */
#endif /* CONFIG_SUNRPC_BACKCHANNEL */
};

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 7c0f9439f94c..284104087190 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -1626,7 +1626,7 @@ static struct svc_xprt *svc_bc_create_socket(struct svc_serv *serv,
set_bit(XPT_CONG_CTRL, &svsk->sk_xprt.xpt_flags);

sn->bc_prep_reply_hdr = svc_tcp_prep_reply_hdr;
- serv->sv_bc_xprt = xprt;
+ serv->sv_bc_enabled = true;

return xprt;
}
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
index 2f7ec8912f49..88694048d5c0 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -136,7 +136,7 @@ static struct svc_xprt *svc_rdma_bc_create(struct svc_serv *serv,

svc_xprt_init(net, &svc_rdma_bc_class, xprt, serv);
set_bit(XPT_CONG_CTRL, &xprt->xpt_flags);
- serv->sv_bc_xprt = xprt;
+ serv->sv_bc_enabled = true;

dprintk("svcrdma: %s(%p)\n", __func__, xprt);
return xprt;
--
2.17.1