NFSv4.x: Add kernel parameter to control the callback server
Add support for the kernel parameter nfs.callback_nr_threads to set
the number of threads that will be assigned to the callback channel.
Add support for the kernel parameter nfs.nfs.max_session_cb_slots
to set the maximum size of the callback channel slot table.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index a9dec32..251e48e 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7463,7 +7463,7 @@
args->bc_attrs.max_resp_sz = max_bc_payload;
args->bc_attrs.max_resp_sz_cached = 0;
args->bc_attrs.max_ops = NFS4_MAX_BACK_CHANNEL_OPS;
- args->bc_attrs.max_reqs = NFS41_BC_MAX_CALLBACKS;
+ args->bc_attrs.max_reqs = min_t(unsigned short, max_session_cb_slots, 1);
dprintk("%s: Back Channel : max_rqst_sz=%u max_resp_sz=%u "
"max_resp_sz_cached=%u max_ops=%u max_reqs=%u\n",
@@ -7510,10 +7510,9 @@
return -EINVAL;
if (rcvd->max_resp_sz_cached > sent->max_resp_sz_cached)
return -EINVAL;
- /* These would render the backchannel useless: */
- if (rcvd->max_ops != sent->max_ops)
+ if (rcvd->max_ops > sent->max_ops)
return -EINVAL;
- if (rcvd->max_reqs != sent->max_reqs)
+ if (rcvd->max_reqs > sent->max_reqs)
return -EINVAL;
out:
return 0;