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|
/*
* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
*/
/*
* This file contains code imported from the OFED rds source file send.c
* Oracle elects to have and use the contents of send.c under and governed
* by the OpenIB.org BSD license (see below for full license text). However,
* the following notice accompanied the original version of this file:
*/
/*
* Copyright (c) 2006 Oracle. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#include <sys/stropts.h>
#include <sys/systm.h>
#include <sys/rds.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/ib/clients/rdsv3/rdsv3.h>
#include <sys/ib/clients/rdsv3/rdma.h>
#include <sys/ib/clients/rdsv3/rdsv3_debug.h>
/*
* When transmitting messages in rdsv3_send_xmit, we need to emerge from
* time to time and briefly release the CPU. Otherwise the softlock watchdog
* will kick our shin.
* Also, it seems fairer to not let one busy connection stall all the
* others.
*
* send_batch_count is the number of times we'll loop in send_xmit. Setting
* it to 0 will restore the old behavior (where we looped until we had
* drained the queue).
*/
static int send_batch_count = 64;
extern void rdsv3_ib_send_unmap_rdma(void *ic, struct rdsv3_rdma_op *op);
/*
* Reset the send state. Caller must hold c_send_lock when calling here.
*/
void
rdsv3_send_reset(struct rdsv3_connection *conn)
{
struct rdsv3_message *rm, *tmp;
struct rdsv3_rdma_op *ro;
RDSV3_DPRINTF4("rdsv3_send_reset", "Enter(conn: %p)", conn);
ASSERT(MUTEX_HELD(&conn->c_send_lock));
if (conn->c_xmit_rm) {
rm = conn->c_xmit_rm;
ro = rm->m_rdma_op;
if (ro && ro->r_mapped) {
RDSV3_DPRINTF2("rdsv3_send_reset",
"rm %p mflg 0x%x map %d mihdl %p sgl %p",
rm, rm->m_flags, ro->r_mapped,
ro->r_rdma_sg[0].mihdl,
ro->r_rdma_sg[0].swr.wr_sgl);
rdsv3_ib_send_unmap_rdma(conn->c_transport_data, ro);
}
/*
* Tell the user the RDMA op is no longer mapped by the
* transport. This isn't entirely true (it's flushed out
* independently) but as the connection is down, there's
* no ongoing RDMA to/from that memory
*/
rdsv3_message_unmapped(conn->c_xmit_rm);
rdsv3_message_put(conn->c_xmit_rm);
conn->c_xmit_rm = NULL;
}
conn->c_xmit_sg = 0;
conn->c_xmit_hdr_off = 0;
conn->c_xmit_data_off = 0;
conn->c_xmit_rdma_sent = 0;
conn->c_map_queued = 0;
conn->c_unacked_packets = rdsv3_sysctl_max_unacked_packets;
conn->c_unacked_bytes = rdsv3_sysctl_max_unacked_bytes;
/* Mark messages as retransmissions, and move them to the send q */
mutex_enter(&conn->c_lock);
RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &conn->c_retrans, m_conn_item) {
set_bit(RDSV3_MSG_ACK_REQUIRED, &rm->m_flags);
set_bit(RDSV3_MSG_RETRANSMITTED, &rm->m_flags);
if (rm->m_rdma_op && rm->m_rdma_op->r_mapped) {
RDSV3_DPRINTF4("_send_reset",
"RT rm %p mflg 0x%x sgl %p",
rm, rm->m_flags,
rm->m_rdma_op->r_rdma_sg[0].swr.wr_sgl);
}
}
list_move_tail(&conn->c_send_queue, &conn->c_retrans);
mutex_exit(&conn->c_lock);
RDSV3_DPRINTF4("rdsv3_send_reset", "Return(conn: %p)", conn);
}
/*
* We're making the concious trade-off here to only send one message
* down the connection at a time.
* Pro:
* - tx queueing is a simple fifo list
* - reassembly is optional and easily done by transports per conn
* - no per flow rx lookup at all, straight to the socket
* - less per-frag memory and wire overhead
* Con:
* - queued acks can be delayed behind large messages
* Depends:
* - small message latency is higher behind queued large messages
* - large message latency isn't starved by intervening small sends
*/
int
rdsv3_send_xmit(struct rdsv3_connection *conn)
{
struct rdsv3_message *rm;
unsigned int tmp;
unsigned int send_quota = send_batch_count;
struct rdsv3_scatterlist *sg;
int ret = 0;
int was_empty = 0;
list_t to_be_dropped;
restart:
if (!rdsv3_conn_up(conn))
goto out;
RDSV3_DPRINTF4("rdsv3_send_xmit", "Enter(conn: %p)", conn);
list_create(&to_be_dropped, sizeof (struct rdsv3_message),
offsetof(struct rdsv3_message, m_conn_item));
/*
* sendmsg calls here after having queued its message on the send
* queue. We only have one task feeding the connection at a time. If
* another thread is already feeding the queue then we back off. This
* avoids blocking the caller and trading per-connection data between
* caches per message.
*/
if (!mutex_tryenter(&conn->c_send_lock)) {
RDSV3_DPRINTF4("rdsv3_send_xmit",
"Another thread running(conn: %p)", conn);
rdsv3_stats_inc(s_send_sem_contention);
ret = -ENOMEM;
goto out;
}
atomic_inc_32(&conn->c_senders);
if (conn->c_trans->xmit_prepare)
conn->c_trans->xmit_prepare(conn);
/*
* spin trying to push headers and data down the connection until
* the connection doesn't make forward progress.
*/
while (--send_quota) {
/*
* See if need to send a congestion map update if we're
* between sending messages. The send_sem protects our sole
* use of c_map_offset and _bytes.
* Note this is used only by transports that define a special
* xmit_cong_map function. For all others, we create allocate
* a cong_map message and treat it just like any other send.
*/
if (conn->c_map_bytes) {
ret = conn->c_trans->xmit_cong_map(conn, conn->c_lcong,
conn->c_map_offset);
if (ret <= 0)
break;
conn->c_map_offset += ret;
conn->c_map_bytes -= ret;
if (conn->c_map_bytes)
continue;
}
/*
* If we're done sending the current message, clear the
* offset and S/G temporaries.
*/
rm = conn->c_xmit_rm;
if (rm != NULL &&
conn->c_xmit_hdr_off == sizeof (struct rdsv3_header) &&
conn->c_xmit_sg == rm->m_nents) {
conn->c_xmit_rm = NULL;
conn->c_xmit_sg = 0;
conn->c_xmit_hdr_off = 0;
conn->c_xmit_data_off = 0;
conn->c_xmit_rdma_sent = 0;
/* Release the reference to the previous message. */
rdsv3_message_put(rm);
rm = NULL;
}
/* If we're asked to send a cong map update, do so. */
if (rm == NULL && test_and_clear_bit(0, &conn->c_map_queued)) {
if (conn->c_trans->xmit_cong_map != NULL) {
conn->c_map_offset = 0;
conn->c_map_bytes =
sizeof (struct rdsv3_header) +
RDSV3_CONG_MAP_BYTES;
continue;
}
rm = rdsv3_cong_update_alloc(conn);
if (IS_ERR(rm)) {
ret = PTR_ERR(rm);
break;
}
conn->c_xmit_rm = rm;
}
/*
* Grab the next message from the send queue, if there is one.
*
* c_xmit_rm holds a ref while we're sending this message down
* the connction. We can use this ref while holding the
* send_sem.. rdsv3_send_reset() is serialized with it.
*/
if (rm == NULL) {
unsigned int len;
mutex_enter(&conn->c_lock);
if (!list_is_empty(&conn->c_send_queue)) {
rm = list_remove_head(&conn->c_send_queue);
rdsv3_message_addref(rm);
/*
* Move the message from the send queue to
* the retransmit
* list right away.
*/
list_insert_tail(&conn->c_retrans, rm);
}
mutex_exit(&conn->c_lock);
if (rm == NULL) {
was_empty = 1;
break;
}
/*
* Unfortunately, the way Infiniband deals with
* RDMA to a bad MR key is by moving the entire
* queue pair to error state. We cold possibly
* recover from that, but right now we drop the
* connection.
* Therefore, we never retransmit messages with
* RDMA ops.
*/
if (rm->m_rdma_op &&
test_bit(RDSV3_MSG_RETRANSMITTED, &rm->m_flags)) {
mutex_enter(&conn->c_lock);
if (test_and_clear_bit(RDSV3_MSG_ON_CONN,
&rm->m_flags))
list_remove_node(&rm->m_conn_item);
list_insert_tail(&to_be_dropped, rm);
mutex_exit(&conn->c_lock);
rdsv3_message_put(rm);
continue;
}
/* Require an ACK every once in a while */
len = ntohl(rm->m_inc.i_hdr.h_len);
if (conn->c_unacked_packets == 0 ||
conn->c_unacked_bytes < len) {
set_bit(RDSV3_MSG_ACK_REQUIRED, &rm->m_flags);
conn->c_unacked_packets =
rdsv3_sysctl_max_unacked_packets;
conn->c_unacked_bytes =
rdsv3_sysctl_max_unacked_bytes;
rdsv3_stats_inc(s_send_ack_required);
} else {
conn->c_unacked_bytes -= len;
conn->c_unacked_packets--;
}
conn->c_xmit_rm = rm;
}
/*
* Try and send an rdma message. Let's see if we can
* keep this simple and require that the transport either
* send the whole rdma or none of it.
*/
if (rm->m_rdma_op && !conn->c_xmit_rdma_sent) {
ret = conn->c_trans->xmit_rdma(conn, rm->m_rdma_op);
if (ret)
break;
conn->c_xmit_rdma_sent = 1;
/*
* The transport owns the mapped memory for now.
* You can't unmap it while it's on the send queue
*/
set_bit(RDSV3_MSG_MAPPED, &rm->m_flags);
}
if (conn->c_xmit_hdr_off < sizeof (struct rdsv3_header) ||
conn->c_xmit_sg < rm->m_nents) {
ret = conn->c_trans->xmit(conn, rm,
conn->c_xmit_hdr_off,
conn->c_xmit_sg,
conn->c_xmit_data_off);
if (ret <= 0)
break;
if (conn->c_xmit_hdr_off <
sizeof (struct rdsv3_header)) {
tmp = min(ret,
sizeof (struct rdsv3_header) -
conn->c_xmit_hdr_off);
conn->c_xmit_hdr_off += tmp;
ret -= tmp;
}
sg = &rm->m_sg[conn->c_xmit_sg];
while (ret) {
tmp = min(ret, rdsv3_sg_len(sg) -
conn->c_xmit_data_off);
conn->c_xmit_data_off += tmp;
ret -= tmp;
if (conn->c_xmit_data_off == rdsv3_sg_len(sg)) {
conn->c_xmit_data_off = 0;
sg++;
conn->c_xmit_sg++;
ASSERT(!(ret != 0 &&
conn->c_xmit_sg == rm->m_nents));
}
}
}
}
/* Nuke any messages we decided not to retransmit. */
if (!list_is_empty(&to_be_dropped))
rdsv3_send_remove_from_sock(&to_be_dropped, RDS_RDMA_DROPPED);
if (conn->c_trans->xmit_complete)
conn->c_trans->xmit_complete(conn);
/*
* We might be racing with another sender who queued a message but
* backed off on noticing that we held the c_send_lock. If we check
* for queued messages after dropping the sem then either we'll
* see the queued message or the queuer will get the sem. If we
* notice the queued message then we trigger an immediate retry.
*
* We need to be careful only to do this when we stopped processing
* the send queue because it was empty. It's the only way we
* stop processing the loop when the transport hasn't taken
* responsibility for forward progress.
*/
mutex_exit(&conn->c_send_lock);
if (conn->c_map_bytes || (send_quota == 0 && !was_empty)) {
/*
* We exhausted the send quota, but there's work left to
* do. Return and (re-)schedule the send worker.
*/
ret = -EAGAIN;
}
atomic_dec_32(&conn->c_senders);
if (ret == 0 && was_empty) {
/*
* A simple bit test would be way faster than taking the
* spin lock
*/
mutex_enter(&conn->c_lock);
if (!list_is_empty(&conn->c_send_queue)) {
rdsv3_stats_inc(s_send_sem_queue_raced);
ret = -EAGAIN;
}
mutex_exit(&conn->c_lock);
}
out:
RDSV3_DPRINTF4("rdsv3_send_xmit", "Return(conn: %p, ret: %d)",
conn, ret);
return (ret);
}
static void
rdsv3_send_sndbuf_remove(struct rdsv3_sock *rs, struct rdsv3_message *rm)
{
uint32_t len = ntohl(rm->m_inc.i_hdr.h_len);
ASSERT(mutex_owned(&rs->rs_lock));
ASSERT(rs->rs_snd_bytes >= len);
rs->rs_snd_bytes -= len;
if (rs->rs_snd_bytes == 0)
rdsv3_stats_inc(s_send_queue_empty);
}
static inline int
rdsv3_send_is_acked(struct rdsv3_message *rm, uint64_t ack,
is_acked_func is_acked)
{
if (is_acked)
return (is_acked(rm, ack));
return (ntohll(rm->m_inc.i_hdr.h_sequence) <= ack);
}
/*
* Returns true if there are no messages on the send and retransmit queues
* which have a sequence number greater than or equal to the given sequence
* number.
*/
int
rdsv3_send_acked_before(struct rdsv3_connection *conn, uint64_t seq)
{
struct rdsv3_message *rm;
int ret = 1;
RDSV3_DPRINTF4("rdsv3_send_acked_before", "Enter(conn: %p)", conn);
mutex_enter(&conn->c_lock);
/* XXX - original code spits out warning */
rm = list_head(&conn->c_retrans);
if (ntohll(rm->m_inc.i_hdr.h_sequence) < seq)
ret = 0;
/* XXX - original code spits out warning */
rm = list_head(&conn->c_send_queue);
if (ntohll(rm->m_inc.i_hdr.h_sequence) < seq)
ret = 0;
mutex_exit(&conn->c_lock);
RDSV3_DPRINTF4("rdsv3_send_acked_before", "Return(conn: %p)", conn);
return (ret);
}
/*
* This is pretty similar to what happens below in the ACK
* handling code - except that we call here as soon as we get
* the IB send completion on the RDMA op and the accompanying
* message.
*/
void
rdsv3_rdma_send_complete(struct rdsv3_message *rm, int status)
{
struct rdsv3_sock *rs = NULL;
struct rdsv3_rdma_op *ro;
struct rdsv3_notifier *notifier;
RDSV3_DPRINTF4("rdsv3_rdma_send_complete", "Enter(rm: %p)", rm);
mutex_enter(&rm->m_rs_lock);
ro = rm->m_rdma_op;
if (test_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags) &&
ro && ro->r_notify && ro->r_notifier) {
notifier = ro->r_notifier;
rs = rm->m_rs;
rdsv3_sk_sock_hold(rdsv3_rs_to_sk(rs));
notifier->n_status = status;
mutex_enter(&rs->rs_lock);
list_insert_tail(&rs->rs_notify_queue, notifier);
mutex_exit(&rs->rs_lock);
ro->r_notifier = NULL;
}
mutex_exit(&rm->m_rs_lock);
if (rs) {
struct rsock *sk = rdsv3_rs_to_sk(rs);
int error;
rdsv3_wake_sk_sleep(rs);
/* wake up anyone waiting in poll */
sk->sk_upcalls->su_recv(sk->sk_upper_handle, NULL,
0, 0, &error, NULL);
if (error != 0) {
RDSV3_DPRINTF2("rdsv3_recv_incoming",
"su_recv returned: %d", error);
}
rdsv3_sk_sock_put(rdsv3_rs_to_sk(rs));
}
RDSV3_DPRINTF4("rdsv3_rdma_send_complete", "Return(rm: %p)", rm);
}
/*
* This is the same as rdsv3_rdma_send_complete except we
* don't do any locking - we have all the ingredients (message,
* socket, socket lock) and can just move the notifier.
*/
static inline void
__rdsv3_rdma_send_complete(struct rdsv3_sock *rs, struct rdsv3_message *rm,
int status)
{
struct rdsv3_rdma_op *ro;
void *ic;
RDSV3_DPRINTF4("__rdsv3_rdma_send_complete",
"Enter(rs: %p, rm: %p)", rs, rm);
ro = rm->m_rdma_op;
if (ro && ro->r_notify && ro->r_notifier) {
ro->r_notifier->n_status = status;
list_insert_tail(&rs->rs_notify_queue, ro->r_notifier);
ro->r_notifier = NULL;
}
/* No need to wake the app - caller does this */
}
/*
* This is called from the IB send completion when we detect
* a RDMA operation that failed with remote access error.
* So speed is not an issue here.
*/
struct rdsv3_message *
rdsv3_send_get_message(struct rdsv3_connection *conn,
struct rdsv3_rdma_op *op)
{
struct rdsv3_message *rm, *tmp, *found = NULL;
RDSV3_DPRINTF4("rdsv3_send_get_message", "Enter(conn: %p)", conn);
mutex_enter(&conn->c_lock);
RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &conn->c_retrans, m_conn_item) {
if (rm->m_rdma_op == op) {
atomic_inc_32(&rm->m_refcount);
found = rm;
goto out;
}
}
RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &conn->c_send_queue,
m_conn_item) {
if (rm->m_rdma_op == op) {
atomic_inc_32(&rm->m_refcount);
found = rm;
break;
}
}
out:
mutex_exit(&conn->c_lock);
return (found);
}
/*
* This removes messages from the socket's list if they're on it. The list
* argument must be private to the caller, we must be able to modify it
* without locks. The messages must have a reference held for their
* position on the list. This function will drop that reference after
* removing the messages from the 'messages' list regardless of if it found
* the messages on the socket list or not.
*/
void
rdsv3_send_remove_from_sock(struct list *messages, int status)
{
struct rdsv3_sock *rs = NULL;
struct rdsv3_message *rm;
RDSV3_DPRINTF4("rdsv3_send_remove_from_sock", "Enter");
while (!list_is_empty(messages)) {
int was_on_sock = 0;
rm = list_remove_head(messages);
/*
* If we see this flag cleared then we're *sure* that someone
* else beat us to removing it from the sock. If we race
* with their flag update we'll get the lock and then really
* see that the flag has been cleared.
*
* The message spinlock makes sure nobody clears rm->m_rs
* while we're messing with it. It does not prevent the
* message from being removed from the socket, though.
*/
mutex_enter(&rm->m_rs_lock);
if (!test_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags))
goto unlock_and_drop;
if (rs != rm->m_rs) {
if (rs) {
rdsv3_wake_sk_sleep(rs);
rdsv3_sk_sock_put(rdsv3_rs_to_sk(rs));
}
rs = rm->m_rs;
rdsv3_sk_sock_hold(rdsv3_rs_to_sk(rs));
}
mutex_enter(&rs->rs_lock);
if (test_and_clear_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags)) {
struct rdsv3_rdma_op *ro = rm->m_rdma_op;
struct rdsv3_notifier *notifier;
list_remove_node(&rm->m_sock_item);
rdsv3_send_sndbuf_remove(rs, rm);
if (ro && ro->r_notifier &&
(status || ro->r_notify)) {
notifier = ro->r_notifier;
list_insert_tail(&rs->rs_notify_queue,
notifier);
if (!notifier->n_status)
notifier->n_status = status;
rm->m_rdma_op->r_notifier = NULL;
}
was_on_sock = 1;
rm->m_rs = NULL;
}
mutex_exit(&rs->rs_lock);
unlock_and_drop:
mutex_exit(&rm->m_rs_lock);
rdsv3_message_put(rm);
if (was_on_sock)
rdsv3_message_put(rm);
}
if (rs) {
rdsv3_wake_sk_sleep(rs);
rdsv3_sk_sock_put(rdsv3_rs_to_sk(rs));
}
RDSV3_DPRINTF4("rdsv3_send_remove_from_sock", "Return");
}
/*
* Transports call here when they've determined that the receiver queued
* messages up to, and including, the given sequence number. Messages are
* moved to the retrans queue when rdsv3_send_xmit picks them off the send
* queue. This means that in the TCP case, the message may not have been
* assigned the m_ack_seq yet - but that's fine as long as tcp_is_acked
* checks the RDSV3_MSG_HAS_ACK_SEQ bit.
*
* XXX It's not clear to me how this is safely serialized with socket
* destruction. Maybe it should bail if it sees SOCK_DEAD.
*/
void
rdsv3_send_drop_acked(struct rdsv3_connection *conn, uint64_t ack,
is_acked_func is_acked)
{
struct rdsv3_message *rm, *tmp;
list_t list;
RDSV3_DPRINTF4("rdsv3_send_drop_acked", "Enter(conn: %p)", conn);
list_create(&list, sizeof (struct rdsv3_message),
offsetof(struct rdsv3_message, m_conn_item));
mutex_enter(&conn->c_lock);
RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &conn->c_retrans, m_conn_item) {
if (!rdsv3_send_is_acked(rm, ack, is_acked))
break;
list_remove_node(&rm->m_conn_item);
list_insert_tail(&list, rm);
clear_bit(RDSV3_MSG_ON_CONN, &rm->m_flags);
}
#if 0
XXX
/* order flag updates with spin locks */
if (!list_is_empty(&list))
smp_mb__after_clear_bit();
#endif
mutex_exit(&conn->c_lock);
/* now remove the messages from the sock list as needed */
rdsv3_send_remove_from_sock(&list, RDS_RDMA_SUCCESS);
RDSV3_DPRINTF4("rdsv3_send_drop_acked", "Return(conn: %p)", conn);
}
void
rdsv3_send_drop_to(struct rdsv3_sock *rs, struct sockaddr_in *dest)
{
struct rdsv3_message *rm, *tmp;
struct rdsv3_connection *conn;
list_t list;
int wake = 0;
RDSV3_DPRINTF4("rdsv3_send_drop_to", "Enter(rs: %p)", rs);
list_create(&list, sizeof (struct rdsv3_message),
offsetof(struct rdsv3_message, m_sock_item));
/* get all the messages we're dropping under the rs lock */
mutex_enter(&rs->rs_lock);
RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &rs->rs_send_queue,
m_sock_item) {
if (dest && (dest->sin_addr.s_addr != rm->m_daddr ||
dest->sin_port != rm->m_inc.i_hdr.h_dport))
continue;
wake = 1;
list_remove(&rs->rs_send_queue, rm);
list_insert_tail(&list, rm);
rdsv3_send_sndbuf_remove(rs, rm);
clear_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags);
}
mutex_exit(&rs->rs_lock);
conn = NULL;
/* now remove the messages from the conn list as needed */
RDSV3_FOR_EACH_LIST_NODE(rm, &list, m_sock_item) {
/*
* We do this here rather than in the loop above, so that
* we don't have to nest m_rs_lock under rs->rs_lock
*/
mutex_enter(&rm->m_rs_lock);
/* If this is a RDMA operation, notify the app. */
__rdsv3_rdma_send_complete(rs, rm, RDS_RDMA_CANCELED);
rm->m_rs = NULL;
mutex_exit(&rm->m_rs_lock);
/*
* If we see this flag cleared then we're *sure* that someone
* else beat us to removing it from the conn. If we race
* with their flag update we'll get the lock and then really
* see that the flag has been cleared.
*/
if (!test_bit(RDSV3_MSG_ON_CONN, &rm->m_flags))
continue;
if (conn != rm->m_inc.i_conn) {
if (conn)
mutex_exit(&conn->c_lock);
conn = rm->m_inc.i_conn;
mutex_enter(&conn->c_lock);
}
if (test_and_clear_bit(RDSV3_MSG_ON_CONN, &rm->m_flags)) {
list_remove_node(&rm->m_conn_item);
rdsv3_message_put(rm);
}
}
if (conn)
mutex_exit(&conn->c_lock);
if (wake)
rdsv3_wake_sk_sleep(rs);
while (!list_is_empty(&list)) {
rm = list_remove_head(&list);
rdsv3_message_wait(rm);
rdsv3_message_put(rm);
}
RDSV3_DPRINTF4("rdsv3_send_drop_to", "Return(rs: %p)", rs);
}
/*
* we only want this to fire once so we use the callers 'queued'. It's
* possible that another thread can race with us and remove the
* message from the flow with RDSV3_CANCEL_SENT_TO.
*/
static int
rdsv3_send_queue_rm(struct rdsv3_sock *rs, struct rdsv3_connection *conn,
struct rdsv3_message *rm, uint16_be_t sport,
uint16_be_t dport, int *queued)
{
uint32_t len;
RDSV3_DPRINTF4("rdsv3_send_queue_rm", "Enter(rs: %p, rm: %p)", rs, rm);
if (*queued)
goto out;
len = ntohl(rm->m_inc.i_hdr.h_len);
/*
* this is the only place which holds both the socket's rs_lock
* and the connection's c_lock
*/
mutex_enter(&rs->rs_lock);
/*
* If there is a little space in sndbuf, we don't queue anything,
* and userspace gets -EAGAIN. But poll() indicates there's send
* room. This can lead to bad behavior (spinning) if snd_bytes isn't
* freed up by incoming acks. So we check the *old* value of
* rs_snd_bytes here to allow the last msg to exceed the buffer,
* and poll() now knows no more data can be sent.
*/
if (rs->rs_snd_bytes < rdsv3_sk_sndbuf(rs)) {
rs->rs_snd_bytes += len;
/*
* let recv side know we are close to send space exhaustion.
* This is probably not the optimal way to do it, as this
* means we set the flag on *all* messages as soon as our
* throughput hits a certain threshold.
*/
if (rs->rs_snd_bytes >= rdsv3_sk_sndbuf(rs) / 2)
set_bit(RDSV3_MSG_ACK_REQUIRED, &rm->m_flags);
list_insert_tail(&rs->rs_send_queue, rm);
set_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags);
rdsv3_message_addref(rm);
rm->m_rs = rs;
/*
* The code ordering is a little weird, but we're
* trying to minimize the time we hold c_lock
*/
rdsv3_message_populate_header(&rm->m_inc.i_hdr, sport,
dport, 0);
rm->m_inc.i_conn = conn;
rdsv3_message_addref(rm); /* XXX - called twice */
mutex_enter(&conn->c_lock);
rm->m_inc.i_hdr.h_sequence = htonll(conn->c_next_tx_seq++);
list_insert_tail(&conn->c_send_queue, rm);
set_bit(RDSV3_MSG_ON_CONN, &rm->m_flags);
mutex_exit(&conn->c_lock);
RDSV3_DPRINTF5("rdsv3_send_queue_rm",
"queued msg %p len %d, rs %p bytes %d seq %llu",
rm, len, rs, rs->rs_snd_bytes,
(unsigned long long)ntohll(
rm->m_inc.i_hdr.h_sequence));
*queued = 1;
}
mutex_exit(&rs->rs_lock);
RDSV3_DPRINTF4("rdsv3_send_queue_rm", "Return(rs: %p)", rs);
out:
return (*queued);
}
static int
rdsv3_cmsg_send(struct rdsv3_sock *rs, struct rdsv3_message *rm,
struct msghdr *msg, int *allocated_mr)
{
struct cmsghdr *cmsg;
int ret = 0;
RDSV3_DPRINTF4("rdsv3_cmsg_send", "Enter(rs: %p)", rs);
for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
if (cmsg->cmsg_level != SOL_RDS)
continue;
RDSV3_DPRINTF4("rdsv3_cmsg_send", "cmsg(%p, %p) type %d",
cmsg, rm, cmsg->cmsg_type);
/*
* As a side effect, RDMA_DEST and RDMA_MAP will set
* rm->m_rdma_cookie and rm->m_rdma_mr.
*/
switch (cmsg->cmsg_type) {
case RDS_CMSG_RDMA_ARGS:
ret = rdsv3_cmsg_rdma_args(rs, rm, cmsg);
break;
case RDS_CMSG_RDMA_DEST:
ret = rdsv3_cmsg_rdma_dest(rs, rm, cmsg);
break;
case RDS_CMSG_RDMA_MAP:
ret = rdsv3_cmsg_rdma_map(rs, rm, cmsg);
if (ret)
*allocated_mr = 1;
break;
default:
return (-EINVAL);
}
if (ret)
break;
}
RDSV3_DPRINTF4("rdsv3_cmsg_send", "Return(rs: %p)", rs);
return (ret);
}
extern unsigned long rdsv3_max_bcopy_size;
int
rdsv3_sendmsg(struct rdsv3_sock *rs, uio_t *uio, struct nmsghdr *msg,
size_t payload_len)
{
struct rsock *sk = rdsv3_rs_to_sk(rs);
struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name;
uint32_be_t daddr;
uint16_be_t dport;
struct rdsv3_message *rm = NULL;
struct rdsv3_connection *conn;
int ret = 0;
int queued = 0, allocated_mr = 0;
int nonblock = msg->msg_flags & MSG_DONTWAIT;
long timeo = rdsv3_sndtimeo(sk, nonblock);
RDSV3_DPRINTF4("rdsv3_sendmsg", "Enter(rs: %p)", rs);
if (msg->msg_namelen) {
/* XXX fail non-unicast destination IPs? */
if (msg->msg_namelen < sizeof (*usin) ||
usin->sin_family != AF_INET_OFFLOAD) {
ret = -EINVAL;
RDSV3_DPRINTF2("rdsv3_sendmsg", "returning: %d", -ret);
goto out;
}
daddr = usin->sin_addr.s_addr;
dport = usin->sin_port;
} else {
/* We only care about consistency with ->connect() */
mutex_enter(&sk->sk_lock);
daddr = rs->rs_conn_addr;
dport = rs->rs_conn_port;
mutex_exit(&sk->sk_lock);
}
/* racing with another thread binding seems ok here */
if (daddr == 0 || rs->rs_bound_addr == 0) {
ret = -ENOTCONN; /* XXX not a great errno */
RDSV3_DPRINTF2("rdsv3_sendmsg", "returning: %d", -ret);
goto out;
}
if (payload_len > rdsv3_max_bcopy_size) {
RDSV3_DPRINTF2("rdsv3_sendmsg", "Message too large: %d",
payload_len);
ret = -EMSGSIZE;
goto out;
}
rm = rdsv3_message_copy_from_user(uio, payload_len);
if (IS_ERR(rm)) {
ret = PTR_ERR(rm);
RDSV3_DPRINTF2("rdsv3_sendmsg",
"rdsv3_message_copy_from_user failed %d", -ret);
rm = NULL;
goto out;
}
rm->m_daddr = daddr;
/* Parse any control messages the user may have included. */
ret = rdsv3_cmsg_send(rs, rm, msg, &allocated_mr);
if (ret) {
RDSV3_DPRINTF2("rdsv3_sendmsg",
"rdsv3_cmsg_send(rs: %p rm: %p msg: %p) returned: %d",
rs, rm, msg, ret);
goto out;
}
/*
* rdsv3_conn_create has a spinlock that runs with IRQ off.
* Caching the conn in the socket helps a lot.
*/
mutex_enter(&rs->rs_conn_lock);
if (rs->rs_conn && rs->rs_conn->c_faddr == daddr) {
conn = rs->rs_conn;
} else {
conn = rdsv3_conn_create_outgoing(rs->rs_bound_addr,
daddr, rs->rs_transport, KM_NOSLEEP);
if (IS_ERR(conn)) {
mutex_exit(&rs->rs_conn_lock);
ret = PTR_ERR(conn);
RDSV3_DPRINTF2("rdsv3_sendmsg",
"rdsv3_conn_create_outgoing failed %d",
-ret);
goto out;
}
rs->rs_conn = conn;
}
mutex_exit(&rs->rs_conn_lock);
if ((rm->m_rdma_cookie || rm->m_rdma_op) &&
conn->c_trans->xmit_rdma == NULL) {
RDSV3_DPRINTF2("rdsv3_sendmsg", "rdma_op %p conn xmit_rdma %p",
rm->m_rdma_op, conn->c_trans->xmit_rdma);
ret = -EOPNOTSUPP;
goto out;
}
/*
* If the connection is down, trigger a connect. We may
* have scheduled a delayed reconnect however - in this case
* we should not interfere.
*/
if (rdsv3_conn_state(conn) == RDSV3_CONN_DOWN &&
!test_and_set_bit(RDSV3_RECONNECT_PENDING, &conn->c_flags))
rdsv3_queue_delayed_work(rdsv3_wq, &conn->c_conn_w, 0);
ret = rdsv3_cong_wait(conn->c_fcong, dport, nonblock, rs);
if (ret) {
mutex_enter(&rs->rs_congested_lock);
rs->rs_seen_congestion = 1;
cv_signal(&rs->rs_congested_cv);
mutex_exit(&rs->rs_congested_lock);
RDSV3_DPRINTF2("rdsv3_sendmsg",
"rdsv3_cong_wait (dport: %d) returned: %d", dport, ret);
goto out;
}
(void) rdsv3_send_queue_rm(rs, conn, rm, rs->rs_bound_port, dport,
&queued);
if (!queued) {
/* rdsv3_stats_inc(s_send_queue_full); */
/* XXX make sure this is reasonable */
if (payload_len > rdsv3_sk_sndbuf(rs)) {
ret = -EMSGSIZE;
RDSV3_DPRINTF2("rdsv3_sendmsg",
"msgsize(%d) too big, returning: %d",
payload_len, -ret);
goto out;
}
if (nonblock) {
ret = -EAGAIN;
RDSV3_DPRINTF3("rdsv3_sendmsg",
"send queue full (%d), returning: %d",
payload_len, -ret);
goto out;
}
#if 0
ret = rdsv3_wait_sig(sk->sk_sleep,
(rdsv3_send_queue_rm(rs, conn, rm, rs->rs_bound_port,
dport, &queued)));
if (ret == 0) {
/* signal/timeout pending */
RDSV3_DPRINTF2("rdsv3_sendmsg",
"woke due to signal: %d", ret);
ret = -ERESTART;
goto out;
}
#else
mutex_enter(&sk->sk_sleep->waitq_mutex);
sk->sk_sleep->waitq_waiters++;
while (!rdsv3_send_queue_rm(rs, conn, rm, rs->rs_bound_port,
dport, &queued)) {
ret = cv_wait_sig(&sk->sk_sleep->waitq_cv,
&sk->sk_sleep->waitq_mutex);
if (ret == 0) {
/* signal/timeout pending */
RDSV3_DPRINTF2("rdsv3_sendmsg",
"woke due to signal: %d", ret);
ret = -EINTR;
sk->sk_sleep->waitq_waiters--;
mutex_exit(&sk->sk_sleep->waitq_mutex);
goto out;
}
}
sk->sk_sleep->waitq_waiters--;
mutex_exit(&sk->sk_sleep->waitq_mutex);
#endif
RDSV3_DPRINTF5("rdsv3_sendmsg", "sendmsg woke queued %d",
queued);
ASSERT(queued);
ret = 0;
}
/*
* By now we've committed to the send. We reuse rdsv3_send_worker()
* to retry sends in the rds thread if the transport asks us to.
*/
rdsv3_stats_inc(s_send_queued);
if (!test_bit(RDSV3_LL_SEND_FULL, &conn->c_flags))
(void) rdsv3_send_worker(&conn->c_send_w.work);
rdsv3_message_put(rm);
RDSV3_DPRINTF4("rdsv3_sendmsg", "Return(rs: %p, len: %d)",
rs, payload_len);
return (payload_len);
out:
/*
* If the user included a RDMA_MAP cmsg, we allocated a MR on the fly.
* If the sendmsg goes through, we keep the MR. If it fails with EAGAIN
* or in any other way, we need to destroy the MR again
*/
if (allocated_mr)
rdsv3_rdma_unuse(rs, rdsv3_rdma_cookie_key(rm->m_rdma_cookie),
1);
if (rm)
rdsv3_message_put(rm);
return (ret);
}
/*
* Reply to a ping packet.
*/
int
rdsv3_send_pong(struct rdsv3_connection *conn, uint16_be_t dport)
{
struct rdsv3_message *rm;
int ret = 0;
RDSV3_DPRINTF4("rdsv3_send_pong", "Enter(conn: %p)", conn);
rm = rdsv3_message_alloc(0, KM_NOSLEEP);
if (!rm) {
ret = -ENOMEM;
goto out;
}
rm->m_daddr = conn->c_faddr;
/*
* If the connection is down, trigger a connect. We may
* have scheduled a delayed reconnect however - in this case
* we should not interfere.
*/
if (rdsv3_conn_state(conn) == RDSV3_CONN_DOWN &&
!test_and_set_bit(RDSV3_RECONNECT_PENDING, &conn->c_flags))
rdsv3_queue_delayed_work(rdsv3_wq, &conn->c_conn_w, 0);
ret = rdsv3_cong_wait(conn->c_fcong, dport, 1, NULL);
if (ret)
goto out;
mutex_enter(&conn->c_lock);
list_insert_tail(&conn->c_send_queue, rm);
set_bit(RDSV3_MSG_ON_CONN, &rm->m_flags);
rdsv3_message_addref(rm);
rm->m_inc.i_conn = conn;
rdsv3_message_populate_header(&rm->m_inc.i_hdr, 0, dport,
conn->c_next_tx_seq);
conn->c_next_tx_seq++;
mutex_exit(&conn->c_lock);
rdsv3_stats_inc(s_send_queued);
rdsv3_stats_inc(s_send_pong);
if (!test_bit(RDSV3_LL_SEND_FULL, &conn->c_flags))
(void) rdsv3_send_xmit(conn);
rdsv3_message_put(rm);
RDSV3_DPRINTF4("rdsv3_send_pong", "Return(conn: %p)", conn);
return (0);
out:
if (rm)
rdsv3_message_put(rm);
return (ret);
}
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