2021-07-15 19:54:58

by Chuck Lever III

[permalink] [raw]
Subject: [PATCH v2 0/7] XDR overhaul of NFS callback service

Trond, please let me know if you want to take these or if I may
handle them through the NFSD tree for v5.15. Thanks.


The purpose of this series is to prepare for the optimization of
svc_process_common() to handle NFSD workloads more efficiently. In
other words, NFSD should be the lubricated common case, and callback
is the use case that takes exceptional paths.

Changes since RFC:
- Removed RQ_DROPME test from nfs_callback_dispatch()
- Restored .pc_encode call-outs to prevent dropped replies
- Fixed whitespace damage

---

Chuck Lever (7):
SUNRPC: Add svc_rqst::rq_auth_stat
SUNRPC: Set rq_auth_stat in the pg_authenticate() callout
SUNRPC: Eliminate the RQ_AUTHERR flag
NFS: Add a private local dispatcher for NFSv4 callback operations
NFS: Remove unused callback void decoder
NFS: Extract the xdr_init_encode/decode() calls from decode_compound
NFS: Clean up the synopsis of callback process_op()


fs/lockd/svc.c | 2 +
fs/nfs/callback.c | 4 ++
fs/nfs/callback_xdr.c | 61 ++++++++++++++++---------------
include/linux/sunrpc/svc.h | 3 +-
include/linux/sunrpc/svcauth.h | 4 +-
include/trace/events/sunrpc.h | 9 ++---
net/sunrpc/auth_gss/svcauth_gss.c | 47 +++++++++++++-----------
net/sunrpc/svc.c | 39 ++++++--------------
net/sunrpc/svcauth.c | 8 ++--
net/sunrpc/svcauth_unix.c | 18 +++++----
10 files changed, 96 insertions(+), 99 deletions(-)

--
Chuck Lever


2021-07-15 19:55:20

by Chuck Lever III

[permalink] [raw]
Subject: [PATCH v2 1/7] SUNRPC: Add svc_rqst::rq_auth_stat

I'd like to take commit 4532608d71c8 ("SUNRPC: Clean up generic
dispatcher code") even further by using only private local SVC
dispatchers for all kernel RPC services. This change would enable
the removal of the logic that switches between
svc_generic_dispatch() and a service's private dispatcher, and
simplify the invocation of the service's pc_release method
so that humans can visually verify that it is always invoked
properly.

All that will come later.

First, let's provide a better way to return authentication errors
from SVC dispatcher functions. Instead of overloading the dispatch
method's *statp argument, add a field to struct svc_rqst that can
hold an error value.

Signed-off-by: Chuck Lever <[email protected]>
---
include/linux/sunrpc/svc.h | 1 +
include/linux/sunrpc/svcauth.h | 4 ++-
include/trace/events/sunrpc.h | 6 +++--
net/sunrpc/auth_gss/svcauth_gss.c | 43 ++++++++++++++++++-------------------
net/sunrpc/svc.c | 17 ++++++++-------
net/sunrpc/svcauth.c | 8 +++----
net/sunrpc/svcauth_unix.c | 12 +++++-----
7 files changed, 46 insertions(+), 45 deletions(-)

diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index e91d51ea028b..35f12963e1ff 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -282,6 +282,7 @@ struct svc_rqst {
void * rq_argp; /* decoded arguments */
void * rq_resp; /* xdr'd results */
void * rq_auth_data; /* flavor-specific data */
+ __be32 rq_auth_stat; /* authentication status */
int rq_auth_slack; /* extra space xdr code
* should leave in head
* for krb5i, krb5p.
diff --git a/include/linux/sunrpc/svcauth.h b/include/linux/sunrpc/svcauth.h
index b0003866a249..6d9cc9080aca 100644
--- a/include/linux/sunrpc/svcauth.h
+++ b/include/linux/sunrpc/svcauth.h
@@ -127,7 +127,7 @@ struct auth_ops {
char * name;
struct module *owner;
int flavour;
- int (*accept)(struct svc_rqst *rq, __be32 *authp);
+ int (*accept)(struct svc_rqst *rq);
int (*release)(struct svc_rqst *rq);
void (*domain_release)(struct auth_domain *);
int (*set_client)(struct svc_rqst *rq);
@@ -149,7 +149,7 @@ struct auth_ops {

struct svc_xprt;

-extern int svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
+extern int svc_authenticate(struct svc_rqst *rqstp);
extern int svc_authorise(struct svc_rqst *rqstp);
extern int svc_set_client(struct svc_rqst *rqstp);
extern int svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h
index 861f199896c6..9f09f5b4d0f8 100644
--- a/include/trace/events/sunrpc.h
+++ b/include/trace/events/sunrpc.h
@@ -1611,9 +1611,9 @@ TRACE_DEFINE_ENUM(SVC_COMPLETE);
{ SVC_COMPLETE, "SVC_COMPLETE" })

TRACE_EVENT(svc_authenticate,
- TP_PROTO(const struct svc_rqst *rqst, int auth_res, __be32 auth_stat),
+ TP_PROTO(const struct svc_rqst *rqst, int auth_res),

- TP_ARGS(rqst, auth_res, auth_stat),
+ TP_ARGS(rqst, auth_res),

TP_STRUCT__entry(
__field(u32, xid)
@@ -1624,7 +1624,7 @@ TRACE_EVENT(svc_authenticate,
TP_fast_assign(
__entry->xid = be32_to_cpu(rqst->rq_xid);
__entry->svc_status = auth_res;
- __entry->auth_stat = be32_to_cpu(auth_stat);
+ __entry->auth_stat = be32_to_cpu(rqst->rq_auth_stat);
),

TP_printk("xid=0x%08x auth_res=%s auth_stat=%s",
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index a81be45f40d9..635449ed7af6 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -707,11 +707,11 @@ svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
/*
* Verify the checksum on the header and return SVC_OK on success.
* Otherwise, return SVC_DROP (in the case of a bad sequence number)
- * or return SVC_DENIED and indicate error in authp.
+ * or return SVC_DENIED and indicate error in rqstp->rq_auth_stat.
*/
static int
gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
- __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp)
+ __be32 *rpcstart, struct rpc_gss_wire_cred *gc)
{
struct gss_ctx *ctx_id = rsci->mechctx;
struct xdr_buf rpchdr;
@@ -725,7 +725,7 @@ gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
xdr_buf_from_iov(&iov, &rpchdr);

- *authp = rpc_autherr_badverf;
+ rqstp->rq_auth_stat = rpc_autherr_badverf;
if (argv->iov_len < 4)
return SVC_DENIED;
flavor = svc_getnl(argv);
@@ -737,13 +737,13 @@ gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
if (rqstp->rq_deferred) /* skip verification of revisited request */
return SVC_OK;
if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
- *authp = rpcsec_gsserr_credproblem;
+ rqstp->rq_auth_stat = rpcsec_gsserr_credproblem;
return SVC_DENIED;
}

if (gc->gc_seq > MAXSEQ) {
trace_rpcgss_svc_seqno_large(rqstp, gc->gc_seq);
- *authp = rpcsec_gsserr_ctxproblem;
+ rqstp->rq_auth_stat = rpcsec_gsserr_ctxproblem;
return SVC_DENIED;
}
if (!gss_check_seq_num(rqstp, rsci, gc->gc_seq))
@@ -1142,7 +1142,7 @@ static void gss_free_in_token_pages(struct gssp_in_token *in_token)
}

static int gss_read_proxy_verf(struct svc_rqst *rqstp,
- struct rpc_gss_wire_cred *gc, __be32 *authp,
+ struct rpc_gss_wire_cred *gc,
struct xdr_netobj *in_handle,
struct gssp_in_token *in_token)
{
@@ -1151,7 +1151,7 @@ static int gss_read_proxy_verf(struct svc_rqst *rqstp,
int pages, i, res, pgto, pgfrom;
size_t inlen, to_offs, from_offs;

- res = gss_read_common_verf(gc, argv, authp, in_handle);
+ res = gss_read_common_verf(gc, argv, &rqstp->rq_auth_stat, in_handle);
if (res)
return res;

@@ -1227,7 +1227,7 @@ gss_write_resv(struct kvec *resv, size_t size_limit,
* Otherwise, drop the request pending an answer to the upcall.
*/
static int svcauth_gss_legacy_init(struct svc_rqst *rqstp,
- struct rpc_gss_wire_cred *gc, __be32 *authp)
+ struct rpc_gss_wire_cred *gc)
{
struct kvec *argv = &rqstp->rq_arg.head[0];
struct kvec *resv = &rqstp->rq_res.head[0];
@@ -1236,7 +1236,7 @@ static int svcauth_gss_legacy_init(struct svc_rqst *rqstp,
struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);

memset(&rsikey, 0, sizeof(rsikey));
- ret = gss_read_verf(gc, argv, authp,
+ ret = gss_read_verf(gc, argv, &rqstp->rq_auth_stat,
&rsikey.in_handle, &rsikey.in_token);
if (ret)
return ret;
@@ -1339,7 +1339,7 @@ static int gss_proxy_save_rsc(struct cache_detail *cd,
}

static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
- struct rpc_gss_wire_cred *gc, __be32 *authp)
+ struct rpc_gss_wire_cred *gc)
{
struct kvec *resv = &rqstp->rq_res.head[0];
struct xdr_netobj cli_handle;
@@ -1351,8 +1351,7 @@ static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);

memset(&ud, 0, sizeof(ud));
- ret = gss_read_proxy_verf(rqstp, gc, authp,
- &ud.in_handle, &ud.in_token);
+ ret = gss_read_proxy_verf(rqstp, gc, &ud.in_handle, &ud.in_token);
if (ret)
return ret;

@@ -1525,7 +1524,7 @@ static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
* response here and return SVC_COMPLETE.
*/
static int
-svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
+svcauth_gss_accept(struct svc_rqst *rqstp)
{
struct kvec *argv = &rqstp->rq_arg.head[0];
struct kvec *resv = &rqstp->rq_res.head[0];
@@ -1538,7 +1537,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
int ret;
struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);

- *authp = rpc_autherr_badcred;
+ rqstp->rq_auth_stat = rpc_autherr_badcred;
if (!svcdata)
svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
if (!svcdata)
@@ -1575,22 +1574,22 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
goto auth_err;

- *authp = rpc_autherr_badverf;
+ rqstp->rq_auth_stat = rpc_autherr_badverf;
switch (gc->gc_proc) {
case RPC_GSS_PROC_INIT:
case RPC_GSS_PROC_CONTINUE_INIT:
if (use_gss_proxy(SVC_NET(rqstp)))
- return svcauth_gss_proxy_init(rqstp, gc, authp);
+ return svcauth_gss_proxy_init(rqstp, gc);
else
- return svcauth_gss_legacy_init(rqstp, gc, authp);
+ return svcauth_gss_legacy_init(rqstp, gc);
case RPC_GSS_PROC_DATA:
case RPC_GSS_PROC_DESTROY:
/* Look up the context, and check the verifier: */
- *authp = rpcsec_gsserr_credproblem;
+ rqstp->rq_auth_stat = rpcsec_gsserr_credproblem;
rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
if (!rsci)
goto auth_err;
- switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
+ switch (gss_verify_header(rqstp, rsci, rpcstart, gc)) {
case SVC_OK:
break;
case SVC_DENIED:
@@ -1600,7 +1599,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
}
break;
default:
- *authp = rpc_autherr_rejectedcred;
+ rqstp->rq_auth_stat = rpc_autherr_rejectedcred;
goto auth_err;
}

@@ -1616,13 +1615,13 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
svc_putnl(resv, RPC_SUCCESS);
goto complete;
case RPC_GSS_PROC_DATA:
- *authp = rpcsec_gsserr_ctxproblem;
+ rqstp->rq_auth_stat = rpcsec_gsserr_ctxproblem;
svcdata->verf_start = resv->iov_base + resv->iov_len;
if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
goto auth_err;
rqstp->rq_cred = rsci->cred;
get_group_info(rsci->cred.cr_group_info);
- *authp = rpc_autherr_badcred;
+ rqstp->rq_auth_stat = rpc_autherr_badcred;
switch (gc->gc_svc) {
case RPC_GSS_SVC_NONE:
break;
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 0de918cb3d90..360dab62b6b4 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1283,7 +1283,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
struct svc_process_info process;
__be32 *statp;
u32 prog, vers;
- __be32 auth_stat, rpc_stat;
+ __be32 rpc_stat;
int auth_res;
__be32 *reply_statp;

@@ -1326,14 +1326,14 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
* We do this before anything else in order to get a decent
* auth verifier.
*/
- auth_res = svc_authenticate(rqstp, &auth_stat);
+ auth_res = svc_authenticate(rqstp);
/* Also give the program a chance to reject this call: */
if (auth_res == SVC_OK && progp) {
- auth_stat = rpc_autherr_badcred;
+ rqstp->rq_auth_stat = rpc_autherr_badcred;
auth_res = progp->pg_authenticate(rqstp);
}
if (auth_res != SVC_OK)
- trace_svc_authenticate(rqstp, auth_res, auth_stat);
+ trace_svc_authenticate(rqstp, auth_res);
switch (auth_res) {
case SVC_OK:
break;
@@ -1392,8 +1392,8 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
goto release_dropit;
if (*statp == rpc_garbage_args)
goto err_garbage;
- auth_stat = svc_get_autherr(rqstp, statp);
- if (auth_stat != rpc_auth_ok)
+ rqstp->rq_auth_stat = svc_get_autherr(rqstp, statp);
+ if (rqstp->rq_auth_stat != rpc_auth_ok)
goto err_release_bad_auth;
} else {
dprintk("svc: calling dispatcher\n");
@@ -1450,13 +1450,14 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
if (procp->pc_release)
procp->pc_release(rqstp);
err_bad_auth:
- dprintk("svc: authentication failed (%d)\n", ntohl(auth_stat));
+ dprintk("svc: authentication failed (%d)\n",
+ be32_to_cpu(rqstp->rq_auth_stat));
serv->sv_stats->rpcbadauth++;
/* Restore write pointer to location of accept status: */
xdr_ressize_check(rqstp, reply_statp);
svc_putnl(resv, 1); /* REJECT */
svc_putnl(resv, 1); /* AUTH_ERROR */
- svc_putnl(resv, ntohl(auth_stat)); /* status */
+ svc_putu32(resv, rqstp->rq_auth_stat); /* status */
goto sendit;

err_bad_prog:
diff --git a/net/sunrpc/svcauth.c b/net/sunrpc/svcauth.c
index 998b196b6176..5a8b8e03fdd4 100644
--- a/net/sunrpc/svcauth.c
+++ b/net/sunrpc/svcauth.c
@@ -59,12 +59,12 @@ svc_put_auth_ops(struct auth_ops *aops)
}

int
-svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
+svc_authenticate(struct svc_rqst *rqstp)
{
rpc_authflavor_t flavor;
struct auth_ops *aops;

- *authp = rpc_auth_ok;
+ rqstp->rq_auth_stat = rpc_auth_ok;

flavor = svc_getnl(&rqstp->rq_arg.head[0]);

@@ -72,7 +72,7 @@ svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)

aops = svc_get_auth_ops(flavor);
if (aops == NULL) {
- *authp = rpc_autherr_badcred;
+ rqstp->rq_auth_stat = rpc_autherr_badcred;
return SVC_DENIED;
}

@@ -80,7 +80,7 @@ svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
init_svc_cred(&rqstp->rq_cred);

rqstp->rq_authop = aops;
- return aops->accept(rqstp, authp);
+ return aops->accept(rqstp);
}
EXPORT_SYMBOL_GPL(svc_authenticate);

diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index 35b7966ac3b3..eacfebf326dd 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -725,7 +725,7 @@ svcauth_unix_set_client(struct svc_rqst *rqstp)
EXPORT_SYMBOL_GPL(svcauth_unix_set_client);

static int
-svcauth_null_accept(struct svc_rqst *rqstp, __be32 *authp)
+svcauth_null_accept(struct svc_rqst *rqstp)
{
struct kvec *argv = &rqstp->rq_arg.head[0];
struct kvec *resv = &rqstp->rq_res.head[0];
@@ -736,12 +736,12 @@ svcauth_null_accept(struct svc_rqst *rqstp, __be32 *authp)

if (svc_getu32(argv) != 0) {
dprintk("svc: bad null cred\n");
- *authp = rpc_autherr_badcred;
+ rqstp->rq_auth_stat = rpc_autherr_badcred;
return SVC_DENIED;
}
if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
dprintk("svc: bad null verf\n");
- *authp = rpc_autherr_badverf;
+ rqstp->rq_auth_stat = rpc_autherr_badverf;
return SVC_DENIED;
}

@@ -785,7 +785,7 @@ struct auth_ops svcauth_null = {


static int
-svcauth_unix_accept(struct svc_rqst *rqstp, __be32 *authp)
+svcauth_unix_accept(struct svc_rqst *rqstp)
{
struct kvec *argv = &rqstp->rq_arg.head[0];
struct kvec *resv = &rqstp->rq_res.head[0];
@@ -827,7 +827,7 @@ svcauth_unix_accept(struct svc_rqst *rqstp, __be32 *authp)
}
groups_sort(cred->cr_group_info);
if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
- *authp = rpc_autherr_badverf;
+ rqstp->rq_auth_stat = rpc_autherr_badverf;
return SVC_DENIED;
}

@@ -839,7 +839,7 @@ svcauth_unix_accept(struct svc_rqst *rqstp, __be32 *authp)
return SVC_OK;

badcred:
- *authp = rpc_autherr_badcred;
+ rqstp->rq_auth_stat = rpc_autherr_badcred;
return SVC_DENIED;
}



2021-07-15 19:55:36

by Chuck Lever III

[permalink] [raw]
Subject: [PATCH v2 4/7] NFS: Add a private local dispatcher for NFSv4 callback operations

The client's NFSv4 callback service is the only remaining user of
svc_generic_dispatch().

Note that the NFSv4 callback service doesn't use the .pc_encode and
.pc_decode callouts in any substantial way, so they are removed.

Signed-off-by: Chuck Lever <[email protected]>
---
fs/nfs/callback_xdr.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index 7ff99155b023..e30374e363a6 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -992,6 +992,15 @@ static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
return rpc_success;
}

+static int
+nfs_callback_dispatch(struct svc_rqst *rqstp, __be32 *statp)
+{
+ const struct svc_procedure *procp = rqstp->rq_procinfo;
+
+ *statp = procp->pc_func(rqstp);
+ return 1;
+}
+
/*
* Define NFS4 callback COMPOUND ops.
*/
@@ -1080,7 +1089,7 @@ const struct svc_version nfs4_callback_version1 = {
.vs_proc = nfs4_callback_procedures1,
.vs_count = nfs4_callback_count1,
.vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
- .vs_dispatch = NULL,
+ .vs_dispatch = nfs_callback_dispatch,
.vs_hidden = true,
.vs_need_cong_ctrl = true,
};
@@ -1092,7 +1101,7 @@ const struct svc_version nfs4_callback_version4 = {
.vs_proc = nfs4_callback_procedures1,
.vs_count = nfs4_callback_count4,
.vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
- .vs_dispatch = NULL,
+ .vs_dispatch = nfs_callback_dispatch,
.vs_hidden = true,
.vs_need_cong_ctrl = true,
};


2021-07-15 19:55:46

by Chuck Lever III

[permalink] [raw]
Subject: [PATCH v2 6/7] NFS: Extract the xdr_init_encode/decode() calls from decode_compound

Clean up: Move the xdr_init_encode() and xdr_init_decode() calls
into the dispatcher, just like the NFSD and lockd dispatchers.

Signed-off-by: Chuck Lever <[email protected]>
---
fs/nfs/callback_xdr.c | 22 +++++++++-------------
1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index c1d08ab1fe22..bf0efec93da8 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -925,22 +925,15 @@ static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
{
struct cb_compound_hdr_arg hdr_arg = { 0 };
struct cb_compound_hdr_res hdr_res = { NULL };
- struct xdr_stream xdr_in, xdr_out;
- __be32 *p, status;
struct cb_process_state cps = {
.drc_status = 0,
.clp = NULL,
.net = SVC_NET(rqstp),
};
unsigned int nops = 0;
+ __be32 status;

- xdr_init_decode(&xdr_in, &rqstp->rq_arg,
- rqstp->rq_arg.head[0].iov_base, NULL);
-
- p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
- xdr_init_encode(&xdr_out, &rqstp->rq_res, p, NULL);
-
- status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
+ status = decode_compound_hdr_arg(&rqstp->rq_arg_stream, &hdr_arg);
if (status == htonl(NFS4ERR_RESOURCE))
return rpc_garbage_args;

@@ -960,15 +953,15 @@ static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
cps.minorversion = hdr_arg.minorversion;
hdr_res.taglen = hdr_arg.taglen;
hdr_res.tag = hdr_arg.tag;
- if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0) {
+ if (encode_compound_hdr_res(&rqstp->rq_res_stream, &hdr_res) != 0) {
if (cps.clp)
nfs_put_client(cps.clp);
return rpc_system_err;
}
while (status == 0 && nops != hdr_arg.nops) {
- status = process_op(nops, rqstp, &xdr_in,
- rqstp->rq_argp, &xdr_out, rqstp->rq_resp,
- &cps);
+ status = process_op(nops, rqstp, &rqstp->rq_arg_stream,
+ rqstp->rq_argp, &rqstp->rq_res_stream,
+ rqstp->rq_resp, &cps);
nops++;
}

@@ -996,6 +989,9 @@ nfs_callback_dispatch(struct svc_rqst *rqstp, __be32 *statp)
{
const struct svc_procedure *procp = rqstp->rq_procinfo;

+ svcxdr_init_decode(rqstp);
+ svcxdr_init_encode(rqstp);
+
*statp = procp->pc_func(rqstp);
return 1;
}


2021-07-15 19:55:58

by Chuck Lever III

[permalink] [raw]
Subject: [PATCH v2 7/7] NFS: Clean up the synopsis of callback process_op()

The xdr_stream and rq_arg and rq_res are already accessible via the
@rqstp parameter.

Signed-off-by: Chuck Lever <[email protected]>
---
fs/nfs/callback_xdr.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index bf0efec93da8..4c48d85f6517 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -863,17 +863,16 @@ preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
}

static __be32 process_op(int nop, struct svc_rqst *rqstp,
- struct xdr_stream *xdr_in, void *argp,
- struct xdr_stream *xdr_out, void *resp,
- struct cb_process_state *cps)
+ struct cb_process_state *cps)
{
+ struct xdr_stream *xdr_out = &rqstp->rq_res_stream;
struct callback_op *op = &callback_ops[0];
unsigned int op_nr;
__be32 status;
long maxlen;
__be32 res;

- status = decode_op_hdr(xdr_in, &op_nr);
+ status = decode_op_hdr(&rqstp->rq_arg_stream, &op_nr);
if (unlikely(status))
return status;

@@ -903,9 +902,11 @@ static __be32 process_op(int nop, struct svc_rqst *rqstp,

maxlen = xdr_out->end - xdr_out->p;
if (maxlen > 0 && maxlen < PAGE_SIZE) {
- status = op->decode_args(rqstp, xdr_in, argp);
+ status = op->decode_args(rqstp, &rqstp->rq_arg_stream,
+ rqstp->rq_argp);
if (likely(status == 0))
- status = op->process_op(argp, resp, cps);
+ status = op->process_op(rqstp->rq_argp, rqstp->rq_resp,
+ cps);
} else
status = htonl(NFS4ERR_RESOURCE);

@@ -914,7 +915,7 @@ static __be32 process_op(int nop, struct svc_rqst *rqstp,
if (unlikely(res))
return res;
if (op->encode_res != NULL && status == 0)
- status = op->encode_res(rqstp, xdr_out, resp);
+ status = op->encode_res(rqstp, xdr_out, rqstp->rq_resp);
return status;
}

@@ -959,9 +960,7 @@ static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
return rpc_system_err;
}
while (status == 0 && nops != hdr_arg.nops) {
- status = process_op(nops, rqstp, &rqstp->rq_arg_stream,
- rqstp->rq_argp, &rqstp->rq_res_stream,
- rqstp->rq_resp, &cps);
+ status = process_op(nops, rqstp, &cps);
nops++;
}



2021-07-15 19:56:00

by Chuck Lever III

[permalink] [raw]
Subject: [PATCH v2 5/7] NFS: Remove unused callback void decoder

Clean up: The callback RPC dispatcher no longer invokes these call
outs, although svc_process_common() relies on seeing a .pc_encode
function.

Signed-off-by: Chuck Lever <[email protected]>
---
fs/nfs/callback_xdr.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index e30374e363a6..c1d08ab1fe22 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -63,11 +63,10 @@ static __be32 nfs4_callback_null(struct svc_rqst *rqstp)
return htonl(NFS4_OK);
}

-static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p)
-{
- return xdr_argsize_check(rqstp, p);
-}
-
+/*
+ * svc_process_common() looks for an XDR encoder to know when
+ * not to drop a Reply.
+ */
static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p)
{
return xdr_ressize_check(rqstp, p);
@@ -1067,7 +1066,6 @@ static struct callback_op callback_ops[] = {
static const struct svc_procedure nfs4_callback_procedures1[] = {
[CB_NULL] = {
.pc_func = nfs4_callback_null,
- .pc_decode = nfs4_decode_void,
.pc_encode = nfs4_encode_void,
.pc_xdrressize = 1,
.pc_name = "NULL",