linux-toradex.git/fs/nfs/callback_xdr.c, branch v6.16

nfsd: don't use sv_nrthreads in connection limiting calculations.

2025-01-06T14:37:36+00:00

The heuristic for limiting the number of incoming connections to nfsd
currently uses sv_nrthreads - allowing more connections if more threads
were configured.

A future patch will allow number of threads to grow dynamically so that
there will be no need to configure sv_nrthreads.  So we need a different
solution for limiting connections.

It isn't clear what problem is solved by limiting connections (as
mentioned in a code comment) but the most likely problem is a connection
storm - many connections that are not doing productive work.  These will
be closed after about 6 minutes already but it might help to slow down a
storm.

This patch adds a per-connection flag XPT_PEER_VALID which indicates
that the peer has presented a filehandle for which it has some sort of
access.  i.e the peer is known to be trusted in some way.  We now only
count connections which have NOT been determined to be valid.  There
should be relative few of these at any given time.

If the number of non-validated peer exceed a limit - currently 64 - we
close the oldest non-validated peer to avoid having too many of these
useless connections.

Note that this patch significantly changes the meaning of the various
configuration parameters for "max connections".  The next patch will
remove all of these.

Signed-off-by: NeilBrown 
Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

SUNRPC: Fix integer overflow in decode_rc_list()

2024-10-03T20:19:13+00:00

The math in "rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t)" could have an
integer overflow.  Add bounds checking on rc_list->rcl_nrefcalls to fix
that.

Fixes: 4aece6a19cf7 ("nfs41: cb_sequence xdr implementation")
Signed-off-by: Dan Carpenter 
Signed-off-by: Anna Schumaker

nfs: fix bitmap decoder to handle a 3rd word

2024-08-22T21:01:10+00:00

It only decodes the first two words at this point. Have it decode the
third word as well. Without this, the client doesn't send delegated
timestamps in the CB_GETATTR response.

With this change we also need to expand the on-stack bitmap in
decode_recallany_args to 3 elements, in case the server sends a larger
bitmap than expected.

Fixes: 43df7110f4a9 ("NFSv4: Add CB_GETATTR support for delegated attributes")
Signed-off-by: Jeff Layton 
Reviewed-by: Benjamin Coddington 
Signed-off-by: Anna Schumaker

NFSv4: Add CB_GETATTR support for delegated attributes

2024-07-08T17:47:25+00:00

When the client holds an attribute delegation, the server may retrieve
all the timestamps through a CB_GETATTR callback.

Signed-off-by: Trond Myklebust 
Signed-off-by: Lance Shelton 
Reviewed-by: Jeff Layton 
Signed-off-by: Trond Myklebust 
Signed-off-by: Anna Schumaker

NFSv4.1: Use the nfs_client's rpc timeouts for backchannel

2024-01-04T22:01:01+00:00

For backchannel requests that lookup the appropriate nfs_client, use the
state-management rpc_clnt's rpc_timeout parameters for the backchannel's
response.  When the nfs_client cannot be found, fall back to using the
xprt's default timeout parameters.

Signed-off-by: Benjamin Coddington 
Tested-by: Chuck Lever 
Tested-by: Jeff Layton 
Signed-off-by: Anna Schumaker

SUNRPC: Use per-CPU counters to tally server RPC counts

2023-02-20T14:20:32+00:00

 - Improves counting accuracy
 - Reduces cross-CPU memory traffic

Signed-off-by: Chuck Lever

SUNRPC: Refactor RPC server dispatch method

2023-02-20T14:20:31+00:00

Currently, svcauth_gss_accept() pre-reserves response buffer space
for the RPC payload length and GSS sequence number before returning
to the dispatcher, which then adds the header's accept_stat field.

The problem is the accept_stat field is supposed to go before the
length and seq_num fields. So svcauth_gss_release() has to relocate
the accept_stat value (see svcauth_gss_prepare_to_wrap()).

To enable these fields to be added to the response buffer in the
correct (final) order, the pointer to the accept_stat has to be made
available to svcauth_gss_accept() so that it can set it before
reserving space for the length and seq_num fields.

As a first step, move the pointer to the location of the accept_stat
field into struct svc_rqst.

Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

SUNRPC: Push svcxdr_init_encode() into svc_process_common()

2023-02-20T14:20:27+00:00

Now that all vs_dispatch functions invoke svcxdr_init_encode(), it
is common code and can be pushed down into the generic RPC server.

Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

SUNRPC: Push svcxdr_init_decode() into svc_process_common()

2023-02-20T14:20:09+00:00

Now that all vs_dispatch functions invoke svcxdr_init_decode(), it
is common code and can be pushed down into the generic RPC server.

Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

SUNRPC: Parametrize how much of argsize should be zeroed

2022-09-26T18:02:42+00:00

Currently, SUNRPC clears the whole of .pc_argsize before processing
each incoming RPC transaction. Add an extra parameter to struct
svc_procedure to enable upper layers to reduce the amount of each
operation's argument structure that is zeroed by SUNRPC.

The size of struct nfsd4_compoundargs, in particular, is a lot to
clear on each incoming RPC Call. A subsequent patch will cut this
down to something closer to what NFSv2 and NFSv3 uses.

This patch should cause no behavior changes.

Signed-off-by: Chuck Lever