diff options
author | Chuck Lever <chuck.lever@oracle.com> | 2016-03-01 13:06:02 -0500 |
---|---|---|
committer | J. Bruce Fields <bfields@redhat.com> | 2016-03-01 13:06:35 -0800 |
commit | 4500632f60fa0d85e4101c374898cdf9b7b0cfac (patch) | |
tree | 108e40fab78bcb843b2a7efa9e6439f8f2d4249b /include | |
parent | f6763c29ab86c3ee27760a06e07bbeab47635b61 (diff) | |
download | linux-stable-4500632f60fa0d85e4101c374898cdf9b7b0cfac.tar.gz linux-stable-4500632f60fa0d85e4101c374898cdf9b7b0cfac.tar.bz2 linux-stable-4500632f60fa0d85e4101c374898cdf9b7b0cfac.zip |
nfsd: Lower NFSv4.1 callback message size limit
The maximum size of a backchannel message on RPC-over-RDMA depends
on the connection's inline threshold. Today that threshold is
typically 1024 bytes, making the maximum message size 996 bytes.
The Linux server's CREATE_SESSION operation checks that the size
of callback Calls can be as large as 1044 bytes, to accommodate
RPCSEC_GSS. Thus CREATE_SESSION fails if a client advertises the
true message size maximum of 996 bytes.
But the server's backchannel currently does not support RPCSEC_GSS.
The actual maximum size it needs is much smaller. It is safe to
reduce the limit to enable NFSv4.1 on RDMA backchannel operation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/sunrpc/auth.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h index 1ecf13e148b8..6a241a277249 100644 --- a/include/linux/sunrpc/auth.h +++ b/include/linux/sunrpc/auth.h @@ -21,10 +21,17 @@ #include <linux/utsname.h> /* + * Maximum size of AUTH_NONE authentication information, in XDR words. + */ +#define NUL_CALLSLACK (4) +#define NUL_REPLYSLACK (2) + +/* * Size of the nodename buffer. RFC1831 specifies a hard limit of 255 bytes, * but Linux hostnames are actually limited to __NEW_UTS_LEN bytes. */ #define UNX_MAXNODENAME __NEW_UTS_LEN +#define UNX_CALLSLACK (21 + XDR_QUADLEN(UNX_MAXNODENAME)) struct rpcsec_gss_info; |