diff mbox series

[v4,4/5] SUNRPC enforce creation of no more than max_connect xprts

Message ID 20210824175108.19746-6-olga.kornievskaia@gmail.com (mailing list archive)
State New, archived
Headers show
Series do not collapse trunkable transports | expand

Commit Message

Olga Kornievskaia Aug. 24, 2021, 5:51 p.m. UTC 
From: Olga Kornievskaia <kolga@netapp.com>

If we are adding new transports via rpc_clnt_test_and_add_xprt()
then check if we've reached the limit. Currently only pnfs path
adds transports via that function but this is done in
preparation when the client would add new transports when
session trunking is detected. A warning is logged if the
limit is reached.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
---
 fs/nfs/client.c             | 1 +
 include/linux/sunrpc/clnt.h | 2 ++
 net/sunrpc/clnt.c           | 9 +++++++++
 3 files changed, 12 insertions(+)

Comments

kernel test robot Aug. 24, 2021, 11:17 p.m. UTC | #1 
Hi Olga,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on nfs/linux-next]
[also build test WARNING on v5.14-rc7 next-20210824]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Olga-Kornievskaia/do-not-collapse-trunkable-transports/20210825-020441
base:   git://git.linux-nfs.org/projects/trondmy/linux-nfs.git linux-next
config: i386-randconfig-s001-20210824 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.3-348-gf0e6938b-dirty
        # https://github.com/0day-ci/linux/commit/9ac1118603b73fd71cf8746cd9a93ddefa97969c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Olga-Kornievskaia/do-not-collapse-trunkable-transports/20210825-020441
        git checkout 9ac1118603b73fd71cf8746cd9a93ddefa97969c
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 SHELL=/bin/bash net/sunrpc/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>


sparse warnings: (new ones prefixed by >>)
>> net/sunrpc/clnt.c:2779:17: sparse: sparse: incompatible types in comparison expression (different address spaces):
>> net/sunrpc/clnt.c:2779:17: sparse:    char const [noderef] __rcu *
>> net/sunrpc/clnt.c:2779:17: sparse:    char const *

vim +2779 net/sunrpc/clnt.c

  2762	
  2763	/**
  2764	 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
  2765	 * @clnt: pointer to struct rpc_clnt
  2766	 * @xps: pointer to struct rpc_xprt_switch,
  2767	 * @xprt: pointer struct rpc_xprt
  2768	 * @dummy: unused
  2769	 */
  2770	int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
  2771			struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
  2772			void *dummy)
  2773	{
  2774		struct rpc_cb_add_xprt_calldata *data;
  2775		struct rpc_task *task;
  2776	
  2777		if (xps->xps_nunique_destaddr_xprts + 1 > clnt->cl_max_connect) {
  2778			rcu_read_lock();
> 2779			pr_warn("SUNRPC: reached max allowed number (%d) did not add "
  2780				"transport to server: %s\n", clnt->cl_max_connect,
  2781				rcu_dereference(xprt->address_strings[RPC_DISPLAY_ADDR]));
  2782			rcu_read_unlock();
  2783			return -EINVAL;
  2784		}
  2785	
  2786		data = kmalloc(sizeof(*data), GFP_NOFS);
  2787		if (!data)
  2788			return -ENOMEM;
  2789		data->xps = xprt_switch_get(xps);
  2790		data->xprt = xprt_get(xprt);
  2791		if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
  2792			rpc_cb_add_xprt_release(data);
  2793			goto success;
  2794		}
  2795	
  2796		task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
  2797				&rpc_cb_add_xprt_call_ops, data);
  2798		data->xps->xps_nunique_destaddr_xprts++;
  2799		rpc_put_task(task);
  2800	success:
  2801		return 1;
  2802	}
  2803	EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
  2804	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 486dec59972b..23e165d5ec9c 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -541,6 +541,7 @@  int nfs_create_rpc_client(struct nfs_client *clp,
 
 	clnt->cl_principal = clp->cl_principal;
 	clp->cl_rpcclient = clnt;
+	clnt->cl_max_connect = clp->cl_max_connect;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index b2edd5fc2f0c..a4661646adc9 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -82,6 +82,7 @@  struct rpc_clnt {
 		struct work_struct	cl_work;
 	};
 	const struct cred	*cl_cred;
+	unsigned int		cl_max_connect; /* max number of transports not to the same IP */
 };
 
 /*
@@ -136,6 +137,7 @@  struct rpc_create_args {
 	char			*client_name;
 	struct svc_xprt		*bc_xprt;	/* NFSv4.1 backchannel */
 	const struct cred	*cred;
+	unsigned int		max_connect;
 };
 
 struct rpc_add_xprt_test {
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 451ac7d031db..05edb2d4b022 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -2787,6 +2787,15 @@  int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
 	struct rpc_cb_add_xprt_calldata *data;
 	struct rpc_task *task;
 
+	if (xps->xps_nunique_destaddr_xprts + 1 > clnt->cl_max_connect) {
+		rcu_read_lock();
+		pr_warn("SUNRPC: reached max allowed number (%d) did not add "
+			"transport to server: %s\n", clnt->cl_max_connect,
+			rcu_dereference(xprt->address_strings[RPC_DISPLAY_ADDR]));
+		rcu_read_unlock();
+		return -EINVAL;
+	}
+
 	data = kmalloc(sizeof(*data), GFP_NOFS);
 	if (!data)
 		return -ENOMEM;