xprtrdma: No direct data placement with krb5i and krb5p
Direct data placement is not allowed when using flavors that
guarantee integrity or privacy. When such security flavors are in
effect, don't allow the use of Read and Write chunks for moving
individual data items. All messages larger than the inline threshold
are sent via Long Call or Long Reply.
On my systems (CX-3 Pro on FDR), for small I/O operations, the use
of Long messages adds only around 5 usecs of latency in each
direction.
Note that when integrity or encryption is used, the host CPU touches
every byte in these messages. Even if it could be used, data
movement offload doesn't buy much in this case.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/include/linux/sunrpc/gss_api.h b/include/linux/sunrpc/gss_api.h
index 1f911cc..68ec78c 100644
--- a/include/linux/sunrpc/gss_api.h
+++ b/include/linux/sunrpc/gss_api.h
@@ -73,6 +73,7 @@
rpc_authflavor_t gss_svc_to_pseudoflavor(struct gss_api_mech *, u32 qop,
u32 service);
u32 gss_pseudoflavor_to_service(struct gss_api_mech *, u32 pseudoflavor);
+bool gss_pseudoflavor_to_datatouch(struct gss_api_mech *, u32 pseudoflavor);
char *gss_service_to_auth_domain_name(struct gss_api_mech *, u32 service);
struct pf_desc {
@@ -81,6 +82,7 @@
u32 service;
char *name;
char *auth_domain_name;
+ bool datatouch;
};
/* Different mechanisms (e.g., krb5 or spkm3) may implement gss-api, and