SUNRPC: Fix rpcgss_context trace event acceptor field

The rpcgss_context trace event acceptor field is a dynamically sized
string that records the "data" parameter. But this parameter is also
dependent on the "len" field to determine the size of the data.

It needs to use __string_len() helper macro where the length can be passed
in. It also incorrectly uses strncpy() to save it instead of
__assign_str(). As these macros can change, it is not wise to open code
them in trace events.

As of commit c759e609030c ("tracing: Remove __assign_str_len()"),
__assign_str() can be used for both __string() and __string_len() fields.
Before that commit, __assign_str_len() is required to be used. This needs
to be noted for backporting. (In actuality, commit c1fa617caeb0 ("tracing:
Rework __assign_str() and __string() to not duplicate getting the string")
is the commit that makes __string_str_len() obsolete).

Cc: stable@vger.kernel.org
Fixes: 0c77668ddb4e ("SUNRPC: Introduce trace points in rpc_auth_gss.ko")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

SUNRPC: Record gss_wrap() errors in svcauth_gss_wrap_priv()

Match the error reporting in the other unwrap and wrap functions.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

SUNRPC: Record gss_get_mic() errors in svcauth_gss_wrap_integ()

An error computing the checksum here is an exceptional event.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

trace: Relocate event helper files

Steven Rostedt says:
> The include/trace/events/ directory should only hold files that
> are to create events, not headers that hold helper functions.
>
> Can you please move them out of include/trace/events/ as that
> directory is "special" in the creation of events.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Leon Romanovsky <leonro@nvidia.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

sunrpc: fix header include guard in trace header

rpcgss.h include protection was protecting against the define for
rpcrdma.h.

Signed-off-by: Thiago Rafael Becker <trbecker@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

SUNRPC: Tracepoints should display tk_pid and cl_clid as a fixed-size field

For certain special cases, RPC-related tracepoints record a -1 as
the task ID or the client ID. It's ugly for a trace event to display
4 billion in these cases.

To help keep SUNRPC tracepoints consistent, create a macro that
defines the print format specifiers for tk_pid and cl_clid. At some
point in the future we might try tk_pid with a wider range of values
than 0..64K so this makes it easier to make that change.

RPC tracepoints now look like this:

<...>-1276 [009] 149.720358: rpc_clnt_new: client=00000005 peer=[192.168.2.55]:20049 program=nfs server=klimt.ib

<...>-1342 [004] 149.921234: rpc_xdr_recvfrom: task:0000001a@00000005 head=[0xff1242d9ab6dc01c,144] page=0 tail=[(nil),0] len=144
<...>-1342 [004] 149.921235: xprt_release_cong: task:0000001a@00000005 snd_task:ffffffff cong=256 cwnd=16384
<...>-1342 [004] 149.921235: xprt_put_cong: task:0000001a@00000005 snd_task:ffffffff cong=0 cwnd=16384

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

treewide: Add missing semicolons to __assign_str uses

The __assign_str macro has an unusual ending semicolon but the vast
majority of uses of the macro already have semicolon termination.

$ git grep -P '\b__assign_str\b' | wc -l
551
$ git grep -P '\b__assign_str\b.*;' | wc -l
480

Add semicolons to the __assign_str() uses without semicolon termination
and all the other uses without semicolon termination via additional defines
that are equivalent to __assign_str() with the eventual goal of removing
the semicolon from the __assign_str() macro definition.

Link: https://lore.kernel.org/lkml/1e068d21106bb6db05b735b4916bb420e6c9842a.camel@perches.com/
Link: https://lkml.kernel.org/r/48a056adabd8f70444475352f617914cef504a45.camel@perches.com

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

SUNRPC: Augment server-side rpcgss tracepoints

Add similar tracepoints to those that were recently added on the
client side to track failures in the integ and priv unwrap paths.

And, let's collect the seqno-specific tracepoints together with a
common naming convention.

Regarding the gss_check_seq_num() changes: everywhere else treats
the GSS sequence number as an unsigned 32-bit integer. As far back
as 2.6.12, I couldn't find a compelling reason to do things
differently here. As a defensive change it's better to eliminate
needless implicit sign conversions.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

SUNRPC: Trace GSS context lifetimes

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

SUNRPC: receive buffer size estimation values almost never change

Avoid unnecessary cache sloshing by placing the buffer size
estimation update logic behind an atomic bit flag.

The size of GSS information included in each wrapped Reply does
not change during the lifetime of a GSS context. Therefore, the
au_rslack and au_ralign fields need to be updated only once after
establishing a fresh GSS credential.

Thus a slack size update must occur after a cred is created,
duplicated, renewed, or expires. I'm not sure I have this exactly
right. A trace point is introduced to track updates to these
variables to enable troubleshooting the problem if I missed a spot.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

SUNRPC: Clean up: Replace dprintk and BUG_ON call sites in svcauth_gss.c

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

SUNRPC: Trace gssproxy upcall results

Record results of a GSS proxy ACCEPT_SEC_CONTEXT upcall and the
svc_authenticate() function to make field debugging of NFS server
Kerberos issues easier.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Bill Baker <bill.baker@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

SUNRPC: Introduce trace points in rpc_auth_gss.ko

Add infrastructure for trace points in the RPC_AUTH_GSS kernel
module, and add a few sample trace points. These report exceptional
or unexpected events, and observe the assignment of GSS sequence
numbers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>