[PATCH net-next 0/7] rxrpc: Miscellany

[PATCH net-next 0/7] rxrpc: Miscellany

[David Howells]

Here are a number of patches that make some changes/fixes and add a couple
of extensions to AF_RXRPC for kernel services to use.  The changes and
fixes are:

 (1) Use time64_t rather than u32 outside of protocol or
     UAPI-representative structures.

 (2) Use the correct time stamp when loading a key from an XDR-encoded
     Kerberos 5 key.

 (3) Fix IPv6 support.

 (4) Fix some places where the error code is being incorrectly made
     positive before returning.

 (5) Remove some white space.

And the extensions:

 (6) Add an end-of-Tx phase notification, thereby allowing kAFS to
     transition the state on its own call record at the correct point,
     rather than having to do it in advance and risk non-completion of the
     call in the wrong state.

 (7) Allow a kernel client call to be retried if it fails on a network
     error, thereby making it possible for kAFS to iterate over a number of
     IP addresses without having to reload the Tx queue and re-encrypt data
     each time.

The patches can be found here also:

	http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=rxrpc-next

Tagged thusly:

	git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
	rxrpc-next-20170829

David
---
Baolin Wang (1):
      net: rxrpc: Replace time_t type with time64_t type

David Howells (6):
      rxrpc: Use correct timestamp from Kerberos 5 ticket
      rxrpc: Fix IPv6 support
      rxrpc: Don't negate call->error before returning it
      rxrpc: Remove some excess whitespace
      rxrpc: Add notification of end-of-Tx phase
      rxrpc: Allow failed client calls to be retried


 Documentation/networking/rxrpc.txt |   57 ++++++++++++++++++++
 fs/afs/rxrpc.c                     |   46 ++++++++++++----
 include/keys/rxrpc-type.h          |   23 ++++++++
 include/net/af_rxrpc.h             |   21 +++++++
 net/rxrpc/af_rxrpc.c               |   75 +++++++++++++++++++++++++-
 net/rxrpc/ar-internal.h            |   25 ++++-----
 net/rxrpc/call_accept.c            |    2 -
 net/rxrpc/call_object.c            |  102 ++++++++++++++++++++++++++++++++++--
 net/rxrpc/conn_client.c            |   17 +++++-
 net/rxrpc/conn_object.c            |    2 -
 net/rxrpc/key.c                    |   22 +++++---
 net/rxrpc/local_event.c            |    2 -
 net/rxrpc/output.c                 |    2 -
 net/rxrpc/peer_event.c             |    6 +-
 net/rxrpc/rxkad.c                  |   22 ++++----
 net/rxrpc/sendmsg.c                |   62 +++++++++++++++-------
 net/rxrpc/utils.c                  |   23 ++++++--
 17 files changed, 419 insertions(+), 90 deletions(-)

[PATCH net-next 1/7] net: rxrpc: Replace time_t type with time64_t type

[David Howells]

From: Baolin Wang <baolin.wang@linaro.org>

Since the 'expiry' variable of 'struct key_preparsed_payload' has been
changed to 'time64_t' type, which is year 2038 safe on 32bits system.

In net/rxrpc subsystem, we need convert 'u32' type to 'time64_t' type
when copying ticket expires time to 'prep->expiry', then this patch
introduces two helper functions to help convert 'u32' to 'time64_t'
type.

This patch also uses ktime_get_real_seconds() to get current time instead
of get_seconds() which is not year 2038 safe on 32bits system.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: David Howells <dhowells@redhat.com>
---

 include/keys/rxrpc-type.h |   23 +++++++++++++++++++++++
 net/rxrpc/ar-internal.h   |    2 +-
 net/rxrpc/key.c           |   22 ++++++++++++++--------
 net/rxrpc/rxkad.c         |   14 +++++++-------
 4 files changed, 45 insertions(+), 16 deletions(-)

diff --git a/include/keys/rxrpc-type.h b/include/keys/rxrpc-type.h
index 5de0673f333b..8cf829dbf20e 100644
--- a/include/keys/rxrpc-type.h
+++ b/include/keys/rxrpc-type.h
@@ -127,4 +127,27 @@ struct rxrpc_key_data_v1 {
 #define AFSTOKEN_K5_ADDRESSES_MAX	16	/* max K5 addresses */
 #define AFSTOKEN_K5_AUTHDATA_MAX	16	/* max K5 pieces of auth data */
 
+/*
+ * Truncate a time64_t to the range from 1970 to 2106 as in the network
+ * protocol.
+ */
+static inline u32 rxrpc_time64_to_u32(time64_t time)
+{
+	if (time < 0)
+		return 0;
+
+	if (time > UINT_MAX)
+		return UINT_MAX;
+
+	return (u32)time;
+}
+
+/*
+ * Extend u32 back to time64_t using the same 1970-2106 range.
+ */
+static inline time64_t rxrpc_u32_to_time64(u32 time)
+{
+	return (time64_t)time;
+}
+
 #endif /* _KEYS_RXRPC_TYPE_H */
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 8c0db9b3e4ab..8cac66774de1 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -894,7 +894,7 @@ extern struct key_type key_type_rxrpc_s;
 
 int rxrpc_request_key(struct rxrpc_sock *, char __user *, int);
 int rxrpc_server_keyring(struct rxrpc_sock *, char __user *, int);
-int rxrpc_get_server_data_key(struct rxrpc_connection *, const void *, time_t,
+int rxrpc_get_server_data_key(struct rxrpc_connection *, const void *, time64_t,
 			      u32);
 
 /*
diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c
index 54369225766e..e2d36619b53a 100644
--- a/net/rxrpc/key.c
+++ b/net/rxrpc/key.c
@@ -92,6 +92,7 @@ static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
 				    const __be32 *xdr, unsigned int toklen)
 {
 	struct rxrpc_key_token *token, **pptoken;
+	time64_t expiry;
 	size_t plen;
 	u32 tktlen;
 
@@ -158,8 +159,9 @@ static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
 	     pptoken = &(*pptoken)->next)
 		continue;
 	*pptoken = token;
-	if (token->kad->expiry < prep->expiry)
-		prep->expiry = token->kad->expiry;
+	expiry = rxrpc_u32_to_time64(token->kad->expiry);
+	if (expiry < prep->expiry)
+		prep->expiry = expiry;
 
 	_leave(" = 0");
 	return 0;
@@ -433,6 +435,7 @@ static int rxrpc_preparse_xdr_rxk5(struct key_preparsed_payload *prep,
 	struct rxrpc_key_token *token, **pptoken;
 	struct rxk5_key *rxk5;
 	const __be32 *end_xdr = xdr + (toklen >> 2);
+	time64_t expiry;
 	int ret;
 
 	_enter(",{%x,%x,%x,%x},%u",
@@ -533,8 +536,9 @@ static int rxrpc_preparse_xdr_rxk5(struct key_preparsed_payload *prep,
 	     pptoken = &(*pptoken)->next)
 		continue;
 	*pptoken = token;
-	if (token->kad->expiry < prep->expiry)
-		prep->expiry = token->kad->expiry;
+	expiry = rxrpc_u32_to_time64(token->kad->expiry);
+	if (expiry < prep->expiry)
+		prep->expiry = expiry;
 
 	_leave(" = 0");
 	return 0;
@@ -691,6 +695,7 @@ static int rxrpc_preparse(struct key_preparsed_payload *prep)
 {
 	const struct rxrpc_key_data_v1 *v1;
 	struct rxrpc_key_token *token, **pp;
+	time64_t expiry;
 	size_t plen;
 	u32 kver;
 	int ret;
@@ -777,8 +782,9 @@ static int rxrpc_preparse(struct key_preparsed_payload *prep)
 	while (*pp)
 		pp = &(*pp)->next;
 	*pp = token;
-	if (token->kad->expiry < prep->expiry)
-		prep->expiry = token->kad->expiry;
+	expiry = rxrpc_u32_to_time64(token->kad->expiry);
+	if (expiry < prep->expiry)
+		prep->expiry = expiry;
 	token = NULL;
 	ret = 0;
 
@@ -955,7 +961,7 @@ int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
  */
 int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
 			      const void *session_key,
-			      time_t expiry,
+			      time64_t expiry,
 			      u32 kvno)
 {
 	const struct cred *cred = current_cred();
@@ -982,7 +988,7 @@ int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
 	data.kver = 1;
 	data.v1.security_index = RXRPC_SECURITY_RXKAD;
 	data.v1.ticket_length = 0;
-	data.v1.expiry = expiry;
+	data.v1.expiry = rxrpc_time64_to_u32(expiry);
 	data.v1.kvno = 0;
 
 	memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index 46d1a1f0b55b..34c86d2bcae5 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -854,7 +854,7 @@ static int rxkad_decrypt_ticket(struct rxrpc_connection *conn,
 				struct sk_buff *skb,
 				void *ticket, size_t ticket_len,
 				struct rxrpc_crypt *_session_key,
-				time_t *_expiry,
+				time64_t *_expiry,
 				u32 *_abort_code)
 {
 	struct skcipher_request *req;
@@ -864,7 +864,7 @@ static int rxkad_decrypt_ticket(struct rxrpc_connection *conn,
 	struct in_addr addr;
 	unsigned int life;
 	const char *eproto;
-	time_t issue, now;
+	time64_t issue, now;
 	bool little_endian;
 	int ret;
 	u32 abort_code;
@@ -960,15 +960,15 @@ static int rxkad_decrypt_ticket(struct rxrpc_connection *conn,
 	if (little_endian) {
 		__le32 stamp;
 		memcpy(&stamp, p, 4);
-		issue = le32_to_cpu(stamp);
+		issue = rxrpc_u32_to_time64(le32_to_cpu(stamp));
 	} else {
 		__be32 stamp;
 		memcpy(&stamp, p, 4);
-		issue = be32_to_cpu(stamp);
+		issue = rxrpc_u32_to_time64(be32_to_cpu(stamp));
 	}
 	p += 4;
-	now = get_seconds();
-	_debug("KIV ISSUE: %lx [%lx]", issue, now);
+	now = ktime_get_real_seconds();
+	_debug("KIV ISSUE: %llx [%llx]", issue, now);
 
 	/* check the ticket is in date */
 	if (issue > now) {
@@ -1053,7 +1053,7 @@ static int rxkad_verify_response(struct rxrpc_connection *conn,
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 	struct rxrpc_crypt session_key;
 	const char *eproto;
-	time_t expiry;
+	time64_t expiry;
 	void *ticket;
 	u32 abort_code, version, kvno, ticket_len, level;
 	__be32 csum;

[PATCH net-next 2/7] rxrpc: Use correct timestamp from Kerberos 5 ticket

[David Howells]

When an XDR-encoded Kerberos 5 ticket is added as an rxrpc-type key, the
expiry time should be drawn from the k5 part of the token union (which was
what was filled in), rather than the kad part of the union.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
---

 net/rxrpc/key.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c
index e2d36619b53a..e7f6b8823eb6 100644
--- a/net/rxrpc/key.c
+++ b/net/rxrpc/key.c
@@ -536,7 +536,7 @@ static int rxrpc_preparse_xdr_rxk5(struct key_preparsed_payload *prep,
 	     pptoken = &(*pptoken)->next)
 		continue;
 	*pptoken = token;
-	expiry = rxrpc_u32_to_time64(token->kad->expiry);
+	expiry = rxrpc_u32_to_time64(token->k5->endtime);
 	if (expiry < prep->expiry)
 		prep->expiry = expiry;
 

[PATCH net-next 3/7] rxrpc: Fix IPv6 support

[David Howells]

Fix IPv6 support in AF_RXRPC in the following ways:

 (1) When extracting the address from a received IPv4 packet, if the local
     transport socket is open for IPv6 then fill out the sockaddr_rxrpc
     struct for an IPv4-mapped-to-IPv6 AF_INET6 transport address instead
     of an AF_INET one.

 (2) When sending CHALLENGE or RESPONSE packets, the transport length needs
     to be set from the sockaddr_rxrpc::transport_len field rather than
     sizeof() on the IPv4 transport address.

 (3) When processing an IPv4 ICMP packet received by an IPv6 socket, set up
     the address correctly before searching for the affected peer.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 net/rxrpc/ar-internal.h |    4 ++--
 net/rxrpc/call_accept.c |    2 +-
 net/rxrpc/conn_object.c |    2 +-
 net/rxrpc/local_event.c |    2 +-
 net/rxrpc/output.c      |    2 +-
 net/rxrpc/peer_event.c  |    6 ++++--
 net/rxrpc/rxkad.c       |    8 ++++----
 net/rxrpc/utils.c       |   23 +++++++++++++++++------
 8 files changed, 31 insertions(+), 18 deletions(-)

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 8cac66774de1..227e24794055 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -830,7 +830,6 @@ void rxrpc_process_connection(struct work_struct *);
  */
 extern unsigned int rxrpc_connection_expiry;
 
-int rxrpc_extract_addr_from_skb(struct sockaddr_rxrpc *, struct sk_buff *);
 struct rxrpc_connection *rxrpc_alloc_connection(gfp_t);
 struct rxrpc_connection *rxrpc_find_connection_rcu(struct rxrpc_local *,
 						   struct sk_buff *);
@@ -1060,7 +1059,8 @@ static inline void rxrpc_sysctl_exit(void) {}
 /*
  * utils.c
  */
-int rxrpc_extract_addr_from_skb(struct sockaddr_rxrpc *, struct sk_buff *);
+int rxrpc_extract_addr_from_skb(struct rxrpc_local *, struct sockaddr_rxrpc *,
+				struct sk_buff *);
 
 static inline bool before(u32 seq1, u32 seq2)
 {
diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c
index ec3383f97d4c..cbd1701e813a 100644
--- a/net/rxrpc/call_accept.c
+++ b/net/rxrpc/call_accept.c
@@ -277,7 +277,7 @@ static struct rxrpc_call *rxrpc_alloc_incoming_call(struct rxrpc_sock *rx,
 		 * anticipation - and to save on stack space.
 		 */
 		xpeer = b->peer_backlog[peer_tail];
-		if (rxrpc_extract_addr_from_skb(&xpeer->srx, skb) < 0)
+		if (rxrpc_extract_addr_from_skb(local, &xpeer->srx, skb) < 0)
 			return NULL;
 
 		peer = rxrpc_lookup_incoming_peer(local, xpeer);
diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
index 929b50d5afe8..fe575798592f 100644
--- a/net/rxrpc/conn_object.c
+++ b/net/rxrpc/conn_object.c
@@ -72,7 +72,7 @@ struct rxrpc_connection *rxrpc_find_connection_rcu(struct rxrpc_local *local,
 
 	_enter(",%x", sp->hdr.cid & RXRPC_CIDMASK);
 
-	if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
+	if (rxrpc_extract_addr_from_skb(local, &srx, skb) < 0)
 		goto not_found;
 
 	k.epoch	= sp->hdr.epoch;
diff --git a/net/rxrpc/local_event.c b/net/rxrpc/local_event.c
index 540d3955c1bc..93b5d910b4a1 100644
--- a/net/rxrpc/local_event.c
+++ b/net/rxrpc/local_event.c
@@ -39,7 +39,7 @@ static void rxrpc_send_version_request(struct rxrpc_local *local,
 
 	_enter("");
 
-	if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
+	if (rxrpc_extract_addr_from_skb(local, &srx, skb) < 0)
 		return;
 
 	msg.msg_name	= &srx.transport;
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 5bd2d0fa4a03..71e6f713fbe7 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -444,7 +444,7 @@ void rxrpc_reject_packets(struct rxrpc_local *local)
 		rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
 		sp = rxrpc_skb(skb);
 
-		if (rxrpc_extract_addr_from_skb(&srx, skb) == 0) {
+		if (rxrpc_extract_addr_from_skb(local, &srx, skb) == 0) {
 			msg.msg_namelen = srx.transport_len;
 
 			code = htonl(skb->priority);
diff --git a/net/rxrpc/peer_event.c b/net/rxrpc/peer_event.c
index 1ed9c0c2e94f..7f749505e699 100644
--- a/net/rxrpc/peer_event.c
+++ b/net/rxrpc/peer_event.c
@@ -37,6 +37,7 @@ static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
 
 	memset(&srx, 0, sizeof(srx));
 	srx.transport_type = local->srx.transport_type;
+	srx.transport_len = local->srx.transport_len;
 	srx.transport.family = local->srx.transport.family;
 
 	/* Can we see an ICMP4 packet on an ICMP6 listening socket?  and vice
@@ -45,7 +46,6 @@ static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
 	switch (srx.transport.family) {
 	case AF_INET:
 		srx.transport.sin.sin_port = serr->port;
-		srx.transport_len = sizeof(struct sockaddr_in);
 		switch (serr->ee.ee_origin) {
 		case SO_EE_ORIGIN_ICMP:
 			_net("Rx ICMP");
@@ -69,7 +69,6 @@ static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
 #ifdef CONFIG_AF_RXRPC_IPV6
 	case AF_INET6:
 		srx.transport.sin6.sin6_port = serr->port;
-		srx.transport_len = sizeof(struct sockaddr_in6);
 		switch (serr->ee.ee_origin) {
 		case SO_EE_ORIGIN_ICMP6:
 			_net("Rx ICMP6");
@@ -79,6 +78,9 @@ static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
 			break;
 		case SO_EE_ORIGIN_ICMP:
 			_net("Rx ICMP on v6 sock");
+			srx.transport.sin6.sin6_addr.s6_addr32[0] = 0;
+			srx.transport.sin6.sin6_addr.s6_addr32[1] = 0;
+			srx.transport.sin6.sin6_addr.s6_addr32[2] = htonl(0xffff);
 			memcpy(srx.transport.sin6.sin6_addr.s6_addr + 12,
 			       skb_network_header(skb) + serr->addr_offset,
 			       sizeof(struct in_addr));
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index 34c86d2bcae5..c38b3a1de56c 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -634,8 +634,8 @@ static int rxkad_issue_challenge(struct rxrpc_connection *conn)
 	challenge.min_level	= htonl(0);
 	challenge.__padding	= 0;
 
-	msg.msg_name	= &conn->params.peer->srx.transport.sin;
-	msg.msg_namelen	= sizeof(conn->params.peer->srx.transport.sin);
+	msg.msg_name	= &conn->params.peer->srx.transport;
+	msg.msg_namelen	= conn->params.peer->srx.transport_len;
 	msg.msg_control	= NULL;
 	msg.msg_controllen = 0;
 	msg.msg_flags	= 0;
@@ -689,8 +689,8 @@ static int rxkad_send_response(struct rxrpc_connection *conn,
 
 	_enter("");
 
-	msg.msg_name	= &conn->params.peer->srx.transport.sin;
-	msg.msg_namelen	= sizeof(conn->params.peer->srx.transport.sin);
+	msg.msg_name	= &conn->params.peer->srx.transport;
+	msg.msg_namelen	= conn->params.peer->srx.transport_len;
 	msg.msg_control	= NULL;
 	msg.msg_controllen = 0;
 	msg.msg_flags	= 0;
diff --git a/net/rxrpc/utils.c b/net/rxrpc/utils.c
index ff7af71c4b49..e801171fa351 100644
--- a/net/rxrpc/utils.c
+++ b/net/rxrpc/utils.c
@@ -17,17 +17,28 @@
 /*
  * Fill out a peer address from a socket buffer containing a packet.
  */
-int rxrpc_extract_addr_from_skb(struct sockaddr_rxrpc *srx, struct sk_buff *skb)
+int rxrpc_extract_addr_from_skb(struct rxrpc_local *local,
+				struct sockaddr_rxrpc *srx,
+				struct sk_buff *skb)
 {
 	memset(srx, 0, sizeof(*srx));
 
 	switch (ntohs(skb->protocol)) {
 	case ETH_P_IP:
-		srx->transport_type = SOCK_DGRAM;
-		srx->transport_len = sizeof(srx->transport.sin);
-		srx->transport.sin.sin_family = AF_INET;
-		srx->transport.sin.sin_port = udp_hdr(skb)->source;
-		srx->transport.sin.sin_addr.s_addr = ip_hdr(skb)->saddr;
+		if (local->srx.transport.family == AF_INET6) {
+			srx->transport_type = SOCK_DGRAM;
+			srx->transport_len = sizeof(srx->transport.sin6);
+			srx->transport.sin6.sin6_family = AF_INET6;
+			srx->transport.sin6.sin6_port = udp_hdr(skb)->source;
+			srx->transport.sin6.sin6_addr.s6_addr32[2] = htonl(0xffff);
+			srx->transport.sin6.sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
+		} else {
+			srx->transport_type = SOCK_DGRAM;
+			srx->transport_len = sizeof(srx->transport.sin);
+			srx->transport.sin.sin_family = AF_INET;
+			srx->transport.sin.sin_port = udp_hdr(skb)->source;
+			srx->transport.sin.sin_addr.s_addr = ip_hdr(skb)->saddr;
+		}
 		return 0;
 
 #ifdef CONFIG_AF_RXRPC_IPV6

[PATCH net-next 4/7] rxrpc: Don't negate call->error before returning it

[David Howells]

call->error is stored as 0 or a negative error code.  Don't negate this
value (ie. make it positive) before returning it from a kernel function
(though it should still be negated before passing to userspace through a
control message).

Signed-off-by: David Howells <dhowells@redhat.com>
---

 net/rxrpc/sendmsg.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index b0d2cda6ec0a..bc7f0241d92b 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -61,7 +61,7 @@ static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
 			  call->cong_cwnd + call->cong_extra))
 			break;
 		if (call->state >= RXRPC_CALL_COMPLETE) {
-			ret = -call->error;
+			ret = call->error;
 			break;
 		}
 		if (signal_pending(current)) {
@@ -364,8 +364,8 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 
 call_terminated:
 	rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
-	_leave(" = %d", -call->error);
-	return -call->error;
+	_leave(" = %d", call->error);
+	return call->error;
 
 maybe_error:
 	if (copied)
@@ -660,7 +660,7 @@ int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
 		break;
 	case RXRPC_CALL_COMPLETE:
 		read_lock_bh(&call->state_lock);
-		ret = -call->error;
+		ret = call->error;
 		read_unlock_bh(&call->state_lock);
 		break;
 	default:

[PATCH net-next 5/7] rxrpc: Remove some excess whitespace

[David Howells]

Remove indentation from some blank lines.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 net/rxrpc/af_rxrpc.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index a2ad4482376f..31e97f714ca9 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -591,13 +591,13 @@ static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
 			    char __user *optval, int __user *_optlen)
 {
 	int optlen;
-	
+
 	if (level != SOL_RXRPC)
 		return -EOPNOTSUPP;
 
 	if (get_user(optlen, _optlen))
 		return -EFAULT;
-	
+
 	switch (optname) {
 	case RXRPC_SUPPORTED_CMSG:
 		if (optlen < sizeof(int))
@@ -606,7 +606,7 @@ static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
 		    put_user(sizeof(int), _optlen))
 			return -EFAULT;
 		return 0;
-		
+
 	default:
 		return -EOPNOTSUPP;
 	}

[PATCH net-next 6/7] rxrpc: Add notification of end-of-Tx phase

[David Howells]

Add a callback to rxrpc_kernel_send_data() so that a kernel service can get
a notification that the AF_RXRPC call has transitioned out the Tx phase and
is now waiting for a reply or a final ACK.

This is called from AF_RXRPC with the call state lock held so the
notification is guaranteed to come before any reply is passed back.

Further, modify the AFS filesystem to make use of this so that we don't have
to change the afs_call state before sending the last bit of data.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 Documentation/networking/rxrpc.txt |   12 +++++++++
 fs/afs/rxrpc.c                     |   46 +++++++++++++++++++++++++++---------
 include/net/af_rxrpc.h             |    5 +++-
 net/rxrpc/sendmsg.c                |   34 +++++++++++++++++++++------
 4 files changed, 77 insertions(+), 20 deletions(-)

diff --git a/Documentation/networking/rxrpc.txt b/Documentation/networking/rxrpc.txt
index 8c70ba5dee4d..92a3c3bd5ac3 100644
--- a/Documentation/networking/rxrpc.txt
+++ b/Documentation/networking/rxrpc.txt
@@ -818,10 +818,15 @@ The kernel interface functions are as follows:
 
  (*) Send data through a call.
 
+	typedef void (*rxrpc_notify_end_tx_t)(struct sock *sk,
+					      unsigned long user_call_ID,
+					      struct sk_buff *skb);
+
 	int rxrpc_kernel_send_data(struct socket *sock,
 				   struct rxrpc_call *call,
 				   struct msghdr *msg,
-				   size_t len);
+				   size_t len,
+				   rxrpc_notify_end_tx_t notify_end_rx);
 
      This is used to supply either the request part of a client call or the
      reply part of a server call.  msg.msg_iovlen and msg.msg_iov specify the
@@ -832,6 +837,11 @@ The kernel interface functions are as follows:
      The msg must not specify a destination address, control data or any flags
      other than MSG_MORE.  len is the total amount of data to transmit.
 
+     notify_end_rx can be NULL or it can be used to specify a function to be
+     called when the call changes state to end the Tx phase.  This function is
+     called with the call-state spinlock held to prevent any reply or final ACK
+     from being delivered first.
+
  (*) Receive data from a call.
 
 	int rxrpc_kernel_recv_data(struct socket *sock,
diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 10743043d431..0bf191f0dbaf 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -292,6 +292,19 @@ static void afs_load_bvec(struct afs_call *call, struct msghdr *msg,
 }
 
 /*
+ * Advance the AFS call state when the RxRPC call ends the transmit phase.
+ */
+static void afs_notify_end_request_tx(struct sock *sock,
+				      struct rxrpc_call *rxcall,
+				      unsigned long call_user_ID)
+{
+	struct afs_call *call = (struct afs_call *)call_user_ID;
+
+	if (call->state == AFS_CALL_REQUESTING)
+		call->state = AFS_CALL_AWAIT_REPLY;
+}
+
+/*
  * attach the data from a bunch of pages on an inode to a call
  */
 static int afs_send_pages(struct afs_call *call, struct msghdr *msg)
@@ -310,14 +323,8 @@ static int afs_send_pages(struct afs_call *call, struct msghdr *msg)
 		bytes = msg->msg_iter.count;
 		nr = msg->msg_iter.nr_segs;
 
-		/* Have to change the state *before* sending the last
-		 * packet as RxRPC might give us the reply before it
-		 * returns from sending the request.
-		 */
-		if (first + nr - 1 >= last)
-			call->state = AFS_CALL_AWAIT_REPLY;
-		ret = rxrpc_kernel_send_data(afs_socket, call->rxcall,
-					     msg, bytes);
+		ret = rxrpc_kernel_send_data(afs_socket, call->rxcall, msg,
+					     bytes, afs_notify_end_request_tx);
 		for (loop = 0; loop < nr; loop++)
 			put_page(bv[loop].bv_page);
 		if (ret < 0)
@@ -409,7 +416,8 @@ int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp,
 	if (!call->send_pages)
 		call->state = AFS_CALL_AWAIT_REPLY;
 	ret = rxrpc_kernel_send_data(afs_socket, rxcall,
-				     &msg, call->request_size);
+				     &msg, call->request_size,
+				     afs_notify_end_request_tx);
 	if (ret < 0)
 		goto error_do_abort;
 
@@ -741,6 +749,20 @@ static int afs_deliver_cm_op_id(struct afs_call *call)
 }
 
 /*
+ * Advance the AFS call state when an RxRPC service call ends the transmit
+ * phase.
+ */
+static void afs_notify_end_reply_tx(struct sock *sock,
+				    struct rxrpc_call *rxcall,
+				    unsigned long call_user_ID)
+{
+	struct afs_call *call = (struct afs_call *)call_user_ID;
+
+	if (call->state == AFS_CALL_REPLYING)
+		call->state = AFS_CALL_AWAIT_ACK;
+}
+
+/*
  * send an empty reply
  */
 void afs_send_empty_reply(struct afs_call *call)
@@ -759,7 +781,8 @@ void afs_send_empty_reply(struct afs_call *call)
 	msg.msg_flags		= 0;
 
 	call->state = AFS_CALL_AWAIT_ACK;
-	switch (rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, 0)) {
+	switch (rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, 0,
+				       afs_notify_end_reply_tx)) {
 	case 0:
 		_leave(" [replied]");
 		return;
@@ -797,7 +820,8 @@ void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
 	msg.msg_flags		= 0;
 
 	call->state = AFS_CALL_AWAIT_ACK;
-	n = rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, len);
+	n = rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, len,
+				   afs_notify_end_reply_tx);
 	if (n >= 0) {
 		/* Success */
 		_leave(" [replied]");
diff --git a/include/net/af_rxrpc.h b/include/net/af_rxrpc.h
index c172709787af..07a47ee6f783 100644
--- a/include/net/af_rxrpc.h
+++ b/include/net/af_rxrpc.h
@@ -21,6 +21,8 @@ struct rxrpc_call;
 
 typedef void (*rxrpc_notify_rx_t)(struct sock *, struct rxrpc_call *,
 				  unsigned long);
+typedef void (*rxrpc_notify_end_tx_t)(struct sock *, struct rxrpc_call *,
+				      unsigned long);
 typedef void (*rxrpc_notify_new_call_t)(struct sock *, struct rxrpc_call *,
 					unsigned long);
 typedef void (*rxrpc_discard_new_call_t)(struct rxrpc_call *, unsigned long);
@@ -37,7 +39,8 @@ struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *,
 					   gfp_t,
 					   rxrpc_notify_rx_t);
 int rxrpc_kernel_send_data(struct socket *, struct rxrpc_call *,
-			   struct msghdr *, size_t);
+			   struct msghdr *, size_t,
+			   rxrpc_notify_end_tx_t);
 int rxrpc_kernel_recv_data(struct socket *, struct rxrpc_call *,
 			   void *, size_t, size_t *, bool, u32 *);
 bool rxrpc_kernel_abort_call(struct socket *, struct rxrpc_call *,
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index bc7f0241d92b..344fdce89823 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -101,11 +101,23 @@ static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
 }
 
 /*
+ * Notify the owner of the call that the transmit phase is ended and the last
+ * packet has been queued.
+ */
+static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
+				rxrpc_notify_end_tx_t notify_end_tx)
+{
+	if (notify_end_tx)
+		notify_end_tx(&rx->sk, call, call->user_call_ID);
+}
+
+/*
  * Queue a DATA packet for transmission, set the resend timeout and send the
  * packet immediately
  */
-static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
-			       bool last)
+static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
+			       struct sk_buff *skb, bool last,
+			       rxrpc_notify_end_tx_t notify_end_tx)
 {
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 	rxrpc_seq_t seq = sp->hdr.seq;
@@ -141,6 +153,7 @@ static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
 		switch (call->state) {
 		case RXRPC_CALL_CLIENT_SEND_REQUEST:
 			call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
+			rxrpc_notify_end_tx(rx, call, notify_end_tx);
 			break;
 		case RXRPC_CALL_SERVER_ACK_REQUEST:
 			call->state = RXRPC_CALL_SERVER_SEND_REPLY;
@@ -153,6 +166,7 @@ static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
 				break;
 		case RXRPC_CALL_SERVER_SEND_REPLY:
 			call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
+			rxrpc_notify_end_tx(rx, call, notify_end_tx);
 			break;
 		default:
 			break;
@@ -189,7 +203,8 @@ static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
  */
 static int rxrpc_send_data(struct rxrpc_sock *rx,
 			   struct rxrpc_call *call,
-			   struct msghdr *msg, size_t len)
+			   struct msghdr *msg, size_t len,
+			   rxrpc_notify_end_tx_t notify_end_tx)
 {
 	struct rxrpc_skb_priv *sp;
 	struct sk_buff *skb;
@@ -350,7 +365,9 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 			if (ret < 0)
 				goto out;
 
-			rxrpc_queue_packet(call, skb, !msg_data_left(msg) && !more);
+			rxrpc_queue_packet(rx, call, skb,
+					   !msg_data_left(msg) && !more,
+					   notify_end_tx);
 			skb = NULL;
 		}
 	} while (msg_data_left(msg) > 0);
@@ -611,7 +628,7 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 		/* Reply phase not begun or not complete for service call. */
 		ret = -EPROTO;
 	} else {
-		ret = rxrpc_send_data(rx, call, msg, len);
+		ret = rxrpc_send_data(rx, call, msg, len, NULL);
 	}
 
 	mutex_unlock(&call->user_mutex);
@@ -631,6 +648,7 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
  * @call: The call to send data through
  * @msg: The data to send
  * @len: The amount of data to send
+ * @notify_end_tx: Notification that the last packet is queued.
  *
  * Allow a kernel service to send data on a call.  The call must be in an state
  * appropriate to sending data.  No control data should be supplied in @msg,
@@ -638,7 +656,8 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
  * more data to come, otherwise this data will end the transmission phase.
  */
 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
-			   struct msghdr *msg, size_t len)
+			   struct msghdr *msg, size_t len,
+			   rxrpc_notify_end_tx_t notify_end_tx)
 {
 	int ret;
 
@@ -656,7 +675,8 @@ int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
 	case RXRPC_CALL_CLIENT_SEND_REQUEST:
 	case RXRPC_CALL_SERVER_ACK_REQUEST:
 	case RXRPC_CALL_SERVER_SEND_REPLY:
-		ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len);
+		ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
+				      notify_end_tx);
 		break;
 	case RXRPC_CALL_COMPLETE:
 		read_lock_bh(&call->state_lock);

[PATCH net-next 7/7] rxrpc: Allow failed client calls to be retried

[David Howells]

Allow a client call that failed on network error to be retried, provided
that the Tx queue still holds DATA packet 1.  This allows an operation to
be submitted to another server or another address for the same server
without having to repackage and re-encrypt the data so far processed.

Two new functions are provided:

 (1) rxrpc_kernel_check_call() - This is used to find out the completion
     state of a call to guess whether it can be retried and whether it
     should be retried.

 (2) rxrpc_kernel_retry_call() - Disconnect the call from its current
     connection, reset the state and submit it as a new client call to a
     new address.  The new address need not match the previous address.

A call may be retried even if all the data hasn't been loaded into it yet;
a partially constructed will be retained at the same point it was at when
an error condition was detected.  msg_data_left() can be used to find out
how much data was packaged before the error occurred.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 Documentation/networking/rxrpc.txt |   45 ++++++++++++++++
 include/net/af_rxrpc.h             |   16 ++++++
 net/rxrpc/af_rxrpc.c               |   69 ++++++++++++++++++++++++
 net/rxrpc/ar-internal.h            |   19 ++-----
 net/rxrpc/call_object.c            |  102 ++++++++++++++++++++++++++++++++++--
 net/rxrpc/conn_client.c            |   17 +++++-
 net/rxrpc/sendmsg.c                |   24 +++++---
 7 files changed, 261 insertions(+), 31 deletions(-)

diff --git a/Documentation/networking/rxrpc.txt b/Documentation/networking/rxrpc.txt
index 92a3c3bd5ac3..810620153a44 100644
--- a/Documentation/networking/rxrpc.txt
+++ b/Documentation/networking/rxrpc.txt
@@ -975,6 +975,51 @@ The kernel interface functions are as follows:
      size should be set when the call is begun.  tx_total_len may not be less
      than zero.
 
+ (*) Check to see the completion state of a call so that the caller can assess
+     whether it needs to be retried.
+
+	enum rxrpc_call_completion {
+		RXRPC_CALL_SUCCEEDED,
+		RXRPC_CALL_REMOTELY_ABORTED,
+		RXRPC_CALL_LOCALLY_ABORTED,
+		RXRPC_CALL_LOCAL_ERROR,
+		RXRPC_CALL_NETWORK_ERROR,
+	};
+
+	int rxrpc_kernel_check_call(struct socket *sock, struct rxrpc_call *call,
+				    enum rxrpc_call_completion *_compl,
+				    u32 *_abort_code);
+
+     On return, -EINPROGRESS will be returned if the call is still ongoing; if
+     it is finished, *_compl will be set to indicate the manner of completion,
+     *_abort_code will be set to any abort code that occurred.  0 will be
+     returned on a successful completion, -ECONNABORTED will be returned if the
+     client failed due to a remote abort and anything else will return an
+     appropriate error code.
+
+     The caller should look at this information to decide if it's worth
+     retrying the call.
+
+ (*) Retry a client call.
+
+	int rxrpc_kernel_retry_call(struct socket *sock,
+				    struct rxrpc_call *call,
+				    struct sockaddr_rxrpc *srx,
+				    struct key *key);
+
+     This attempts to partially reinitialise a call and submit it again whilst
+     reusing the original call's Tx queue to avoid the need to repackage and
+     re-encrypt the data to be sent.  call indicates the call to retry, srx the
+     new address to send it to and key the encryption key to use for signing or
+     encrypting the packets.
+
+     For this to work, the first Tx data packet must still be in the transmit
+     queue, and currently this is only permitted for local and network errors
+     and the call must not have been aborted.  Any partially constructed Tx
+     packet is left as is and can continue being filled afterwards.
+
+     It returns 0 if the call was requeued and an error otherwise.
+
 
 =======================
 CONFIGURABLE PARAMETERS
diff --git a/include/net/af_rxrpc.h b/include/net/af_rxrpc.h
index 07a47ee6f783..3ac79150291f 100644
--- a/include/net/af_rxrpc.h
+++ b/include/net/af_rxrpc.h
@@ -19,6 +19,18 @@ struct sock;
 struct socket;
 struct rxrpc_call;
 
+/*
+ * Call completion condition (state == RXRPC_CALL_COMPLETE).
+ */
+enum rxrpc_call_completion {
+	RXRPC_CALL_SUCCEEDED,		/* - Normal termination */
+	RXRPC_CALL_REMOTELY_ABORTED,	/* - call aborted by peer */
+	RXRPC_CALL_LOCALLY_ABORTED,	/* - call aborted locally on error or close */
+	RXRPC_CALL_LOCAL_ERROR,		/* - call failed due to local error */
+	RXRPC_CALL_NETWORK_ERROR,	/* - call terminated by network error */
+	NR__RXRPC_CALL_COMPLETIONS
+};
+
 typedef void (*rxrpc_notify_rx_t)(struct sock *, struct rxrpc_call *,
 				  unsigned long);
 typedef void (*rxrpc_notify_end_tx_t)(struct sock *, struct rxrpc_call *,
@@ -51,5 +63,9 @@ void rxrpc_kernel_get_peer(struct socket *, struct rxrpc_call *,
 int rxrpc_kernel_charge_accept(struct socket *, rxrpc_notify_rx_t,
 			       rxrpc_user_attach_call_t, unsigned long, gfp_t);
 void rxrpc_kernel_set_tx_length(struct socket *, struct rxrpc_call *, s64);
+int rxrpc_kernel_retry_call(struct socket *, struct rxrpc_call *,
+			    struct sockaddr_rxrpc *, struct key *);
+int rxrpc_kernel_check_call(struct socket *, struct rxrpc_call *,
+			    enum rxrpc_call_completion *, u32 *);
 
 #endif /* _NET_RXRPC_H */
diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index 31e97f714ca9..fb17552fd292 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -337,6 +337,75 @@ void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
 EXPORT_SYMBOL(rxrpc_kernel_end_call);
 
 /**
+ * rxrpc_kernel_check_call - Check a call's state
+ * @sock: The socket the call is on
+ * @call: The call to check
+ * @_compl: Where to store the completion state
+ * @_abort_code: Where to store any abort code
+ *
+ * Allow a kernel service to query the state of a call and find out the manner
+ * of its termination if it has completed.  Returns -EINPROGRESS if the call is
+ * still going, 0 if the call finished successfully, -ECONNABORTED if the call
+ * was aborted and an appropriate error if the call failed in some other way.
+ */
+int rxrpc_kernel_check_call(struct socket *sock, struct rxrpc_call *call,
+			    enum rxrpc_call_completion *_compl, u32 *_abort_code)
+{
+	if (call->state != RXRPC_CALL_COMPLETE)
+		return -EINPROGRESS;
+	smp_rmb();
+	*_compl = call->completion;
+	*_abort_code = call->abort_code;
+	return call->error;
+}
+EXPORT_SYMBOL(rxrpc_kernel_check_call);
+
+/**
+ * rxrpc_kernel_retry_call - Allow a kernel service to retry a call
+ * @sock: The socket the call is on
+ * @call: The call to retry
+ * @srx: The address of the peer to contact
+ * @key: The security context to use (defaults to socket setting)
+ *
+ * Allow a kernel service to try resending a client call that failed due to a
+ * network error to a new address.  The Tx queue is maintained intact, thereby
+ * relieving the need to re-encrypt any request data that has already been
+ * buffered.
+ */
+int rxrpc_kernel_retry_call(struct socket *sock, struct rxrpc_call *call,
+			    struct sockaddr_rxrpc *srx, struct key *key)
+{
+	struct rxrpc_conn_parameters cp;
+	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
+	int ret;
+
+	_enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
+
+	if (!key)
+		key = rx->key;
+	if (key && !key->payload.data[0])
+		key = NULL; /* a no-security key */
+
+	memset(&cp, 0, sizeof(cp));
+	cp.local		= rx->local;
+	cp.key			= key;
+	cp.security_level	= 0;
+	cp.exclusive		= false;
+	cp.service_id		= srx->srx_service;
+
+	mutex_lock(&call->user_mutex);
+
+	ret = rxrpc_prepare_call_for_retry(rx, call);
+	if (ret == 0)
+		ret = rxrpc_retry_client_call(rx, call, &cp, srx, GFP_KERNEL);
+
+	mutex_unlock(&call->user_mutex);
+	_leave(" = %d", ret);
+	return ret;
+}
+EXPORT_SYMBOL(rxrpc_kernel_retry_call);
+
+/**
  * rxrpc_kernel_new_call_notification - Get notifications of new calls
  * @sock: The socket to intercept received messages on
  * @notify_new_call: Function to be called when new calls appear
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 227e24794055..ea5600b747cc 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -445,6 +445,7 @@ enum rxrpc_call_flag {
 	RXRPC_CALL_EXPOSED,		/* The call was exposed to the world */
 	RXRPC_CALL_RX_LAST,		/* Received the last packet (at rxtx_top) */
 	RXRPC_CALL_TX_LAST,		/* Last packet in Tx buffer (at rxtx_top) */
+	RXRPC_CALL_TX_LASTQ,		/* Last packet has been queued */
 	RXRPC_CALL_SEND_PING,		/* A ping will need to be sent */
 	RXRPC_CALL_PINGING,		/* Ping in process */
 	RXRPC_CALL_RETRANS_TIMEOUT,	/* Retransmission due to timeout occurred */
@@ -482,18 +483,6 @@ enum rxrpc_call_state {
 };
 
 /*
- * Call completion condition (state == RXRPC_CALL_COMPLETE).
- */
-enum rxrpc_call_completion {
-	RXRPC_CALL_SUCCEEDED,		/* - Normal termination */
-	RXRPC_CALL_REMOTELY_ABORTED,	/* - call aborted by peer */
-	RXRPC_CALL_LOCALLY_ABORTED,	/* - call aborted locally on error or close */
-	RXRPC_CALL_LOCAL_ERROR,		/* - call failed due to local error */
-	RXRPC_CALL_NETWORK_ERROR,	/* - call terminated by network error */
-	NR__RXRPC_CALL_COMPLETIONS
-};
-
-/*
  * Call Tx congestion management modes.
  */
 enum rxrpc_congest_mode {
@@ -687,9 +676,15 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *,
 					 struct rxrpc_conn_parameters *,
 					 struct sockaddr_rxrpc *,
 					 unsigned long, s64, gfp_t);
+int rxrpc_retry_client_call(struct rxrpc_sock *,
+			    struct rxrpc_call *,
+			    struct rxrpc_conn_parameters *,
+			    struct sockaddr_rxrpc *,
+			    gfp_t);
 void rxrpc_incoming_call(struct rxrpc_sock *, struct rxrpc_call *,
 			 struct sk_buff *);
 void rxrpc_release_call(struct rxrpc_sock *, struct rxrpc_call *);
+int rxrpc_prepare_call_for_retry(struct rxrpc_sock *, struct rxrpc_call *);
 void rxrpc_release_calls_on_socket(struct rxrpc_sock *);
 bool __rxrpc_queue_call(struct rxrpc_call *);
 bool rxrpc_queue_call(struct rxrpc_call *);
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index d7809a0620b4..fcdd6555a820 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -269,11 +269,6 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 	trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
 			 here, NULL);
 
-	spin_lock_bh(&call->conn->params.peer->lock);
-	hlist_add_head(&call->error_link,
-		       &call->conn->params.peer->error_targets);
-	spin_unlock_bh(&call->conn->params.peer->lock);
-
 	rxrpc_start_call_timer(call);
 
 	_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
@@ -304,6 +299,48 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 }
 
 /*
+ * Retry a call to a new address.  It is expected that the Tx queue of the call
+ * will contain data previously packaged for an old call.
+ */
+int rxrpc_retry_client_call(struct rxrpc_sock *rx,
+			    struct rxrpc_call *call,
+			    struct rxrpc_conn_parameters *cp,
+			    struct sockaddr_rxrpc *srx,
+			    gfp_t gfp)
+{
+	const void *here = __builtin_return_address(0);
+	int ret;
+
+	/* Set up or get a connection record and set the protocol parameters,
+	 * including channel number and call ID.
+	 */
+	ret = rxrpc_connect_call(call, cp, srx, gfp);
+	if (ret < 0)
+		goto error;
+
+	trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
+			 here, NULL);
+
+	rxrpc_start_call_timer(call);
+
+	_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
+
+	if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
+		rxrpc_queue_call(call);
+
+	_leave(" = 0");
+	return 0;
+
+error:
+	rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
+				  RX_CALL_DEAD, ret);
+	trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
+			 here, ERR_PTR(ret));
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
  * Set up an incoming call.  call->conn points to the connection.
  * This is called in BH context and isn't allowed to fail.
  */
@@ -471,6 +508,61 @@ void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 }
 
 /*
+ * Prepare a kernel service call for retry.
+ */
+int rxrpc_prepare_call_for_retry(struct rxrpc_sock *rx, struct rxrpc_call *call)
+{
+	const void *here = __builtin_return_address(0);
+	int i;
+	u8 last = 0;
+
+	_enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
+
+	trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
+			 here, (const void *)call->flags);
+
+	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
+	ASSERTCMP(call->completion, !=, RXRPC_CALL_REMOTELY_ABORTED);
+	ASSERTCMP(call->completion, !=, RXRPC_CALL_LOCALLY_ABORTED);
+	ASSERT(list_empty(&call->recvmsg_link));
+
+	del_timer_sync(&call->timer);
+
+	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, call->conn);
+
+	if (call->conn)
+		rxrpc_disconnect_call(call);
+
+	if (rxrpc_is_service_call(call) ||
+	    !call->tx_phase ||
+	    call->tx_hard_ack != 0 ||
+	    call->rx_hard_ack != 0 ||
+	    call->rx_top != 0)
+		return -EINVAL;
+
+	call->state = RXRPC_CALL_UNINITIALISED;
+	call->completion = RXRPC_CALL_SUCCEEDED;
+	call->call_id = 0;
+	call->cid = 0;
+	call->cong_cwnd = 0;
+	call->cong_extra = 0;
+	call->cong_ssthresh = 0;
+	call->cong_mode = 0;
+	call->cong_dup_acks = 0;
+	call->cong_cumul_acks = 0;
+	call->acks_lowest_nak = 0;
+
+	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
+		last |= call->rxtx_annotations[i];
+		call->rxtx_annotations[i] &= RXRPC_TX_ANNO_LAST;
+		call->rxtx_annotations[i] |= RXRPC_TX_ANNO_RETRANS;
+	}
+
+	_leave(" = 0");
+	return 0;
+}
+
+/*
  * release all the calls associated with a socket
  */
 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c
index eb2157680399..5f9624bd311c 100644
--- a/net/rxrpc/conn_client.c
+++ b/net/rxrpc/conn_client.c
@@ -555,7 +555,10 @@ static void rxrpc_activate_one_channel(struct rxrpc_connection *conn,
 	trace_rxrpc_client(conn, channel, rxrpc_client_chan_activate);
 
 	write_lock_bh(&call->state_lock);
-	call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
+	if (!test_bit(RXRPC_CALL_TX_LASTQ, &call->flags))
+		call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
+	else
+		call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
 	write_unlock_bh(&call->state_lock);
 
 	rxrpc_see_call(call);
@@ -688,15 +691,23 @@ int rxrpc_connect_call(struct rxrpc_call *call,
 
 	ret = rxrpc_get_client_conn(call, cp, srx, gfp);
 	if (ret < 0)
-		return ret;
+		goto out;
 
 	rxrpc_animate_client_conn(rxnet, call->conn);
 	rxrpc_activate_channels(call->conn);
 
 	ret = rxrpc_wait_for_channel(call, gfp);
-	if (ret < 0)
+	if (ret < 0) {
 		rxrpc_disconnect_client_call(call);
+		goto out;
+	}
+
+	spin_lock_bh(&call->conn->params.peer->lock);
+	hlist_add_head(&call->error_link,
+		       &call->conn->params.peer->error_targets);
+	spin_unlock_bh(&call->conn->params.peer->lock);
 
+out:
 	_leave(" = %d", ret);
 	return ret;
 }
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 344fdce89823..9ea6f972767e 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -128,8 +128,10 @@ static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
 
 	ASSERTCMP(seq, ==, call->tx_top + 1);
 
-	if (last)
+	if (last) {
 		annotation |= RXRPC_TX_ANNO_LAST;
+		set_bit(RXRPC_CALL_TX_LASTQ, &call->flags);
+	}
 
 	/* We have to set the timestamp before queueing as the retransmit
 	 * algorithm can see the packet as soon as we queue it.
@@ -326,11 +328,6 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 				call->tx_total_len -= copy;
 		}
 
-		/* check for the far side aborting the call or a network error
-		 * occurring */
-		if (call->state == RXRPC_CALL_COMPLETE)
-			goto call_terminated;
-
 		/* add the packet to the send queue if it's now full */
 		if (sp->remain <= 0 ||
 		    (msg_data_left(msg) == 0 && !more)) {
@@ -370,6 +367,16 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 					   notify_end_tx);
 			skb = NULL;
 		}
+
+		/* Check for the far side aborting the call or a network error
+		 * occurring.  If this happens, save any packet that was under
+		 * construction so that in the case of a network error, the
+		 * call can be retried or redirected.
+		 */
+		if (call->state == RXRPC_CALL_COMPLETE) {
+			ret = call->error;
+			goto out;
+		}
 	} while (msg_data_left(msg) > 0);
 
 success:
@@ -379,11 +386,6 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 	_leave(" = %d", ret);
 	return ret;
 
-call_terminated:
-	rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
-	_leave(" = %d", call->error);
-	return call->error;
-
 maybe_error:
 	if (copied)
 		goto success;

Re: [PATCH net-next 0/7] rxrpc: Miscellany

[David Miller]

From: David Howells <dhowells@redhat.com>
Date: Tue, 29 Aug 2017 13:26:47 +0100

> 
> Here are a number of patches that make some changes/fixes and add a couple
> of extensions to AF_RXRPC for kernel services to use.  The changes and
> fixes are:
 ...
> Tagged thusly:
> 
> 	git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
> 	rxrpc-next-20170829

Pulled, thanks David.