From 1fc0703af3143914a389bfa081c7acb09502ed5d Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 2 Jan 2015 16:25:08 -0500 Subject: [PATCH] NFSv4.1: Fix client id trunking on Linux Currently, our trunking code will check for session trunking, but will fail to detect client id trunking. This is a problem, because it means that the client will fail to recognise that the two connections represent shared state, even if they do not permit a shared session. By removing the check for the server minor id, and only checking the major id, we will end up doing the right thing in both cases: we close down the new nfs_client and fall back to using the existing one. Fixes: 05f4c350ee02e ("NFS: Discover NFSv4 server trunking when mounting") Cc: Chuck Lever Cc: stable@vger.kernel.org # 3.7.x Tested-by: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/nfs4client.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index 03311259b0c4..d949d0f378ec 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -566,20 +566,14 @@ static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b) } /* - * Returns true if the server owners match + * Returns true if the server major ids match */ static bool -nfs4_match_serverowners(struct nfs_client *a, struct nfs_client *b) +nfs4_check_clientid_trunking(struct nfs_client *a, struct nfs_client *b) { struct nfs41_server_owner *o1 = a->cl_serverowner; struct nfs41_server_owner *o2 = b->cl_serverowner; - if (o1->minor_id != o2->minor_id) { - dprintk("NFS: --> %s server owner minor IDs do not match\n", - __func__); - return false; - } - if (o1->major_id_sz != o2->major_id_sz) goto out_major_mismatch; if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0) @@ -654,7 +648,12 @@ int nfs41_walk_client_list(struct nfs_client *new, if (!nfs4_match_clientids(pos, new)) continue; - if (!nfs4_match_serverowners(pos, new)) + /* + * Note that session trunking is just a special subcase of + * client id trunking. In either case, we want to fall back + * to using the existing nfs_client. + */ + if (!nfs4_check_clientid_trunking(pos, new)) continue; atomic_inc(&pos->cl_count);