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-rw-r--r--net/rxrpc/sendmsg.c882
1 files changed, 882 insertions, 0 deletions
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
new file mode 100644
index 000000000..71e40f91d
--- /dev/null
+++ b/net/rxrpc/sendmsg.c
@@ -0,0 +1,882 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* AF_RXRPC sendmsg() implementation.
+ *
+ * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/net.h>
+#include <linux/gfp.h>
+#include <linux/skbuff.h>
+#include <linux/export.h>
+#include <linux/sched/signal.h>
+
+#include <net/sock.h>
+#include <net/af_rxrpc.h>
+#include "ar-internal.h"
+
+/*
+ * Return true if there's sufficient Tx queue space.
+ */
+static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
+{
+ unsigned int win_size =
+ min_t(unsigned int, call->tx_winsize,
+ call->cong_cwnd + call->cong_extra);
+ rxrpc_seq_t tx_win = READ_ONCE(call->tx_hard_ack);
+
+ if (_tx_win)
+ *_tx_win = tx_win;
+ return call->tx_top - tx_win < win_size;
+}
+
+/*
+ * Wait for space to appear in the Tx queue or a signal to occur.
+ */
+static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
+ struct rxrpc_call *call,
+ long *timeo)
+{
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (rxrpc_check_tx_space(call, NULL))
+ return 0;
+
+ if (call->state >= RXRPC_CALL_COMPLETE)
+ return call->error;
+
+ if (signal_pending(current))
+ return sock_intr_errno(*timeo);
+
+ trace_rxrpc_transmit(call, rxrpc_transmit_wait);
+ *timeo = schedule_timeout(*timeo);
+ }
+}
+
+/*
+ * Wait for space to appear in the Tx queue uninterruptibly, but with
+ * a timeout of 2*RTT if no progress was made and a signal occurred.
+ */
+static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
+ struct rxrpc_call *call)
+{
+ rxrpc_seq_t tx_start, tx_win;
+ signed long rtt, timeout;
+
+ rtt = READ_ONCE(call->peer->srtt_us) >> 3;
+ rtt = usecs_to_jiffies(rtt) * 2;
+ if (rtt < 2)
+ rtt = 2;
+
+ timeout = rtt;
+ tx_start = READ_ONCE(call->tx_hard_ack);
+
+ for (;;) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+
+ tx_win = READ_ONCE(call->tx_hard_ack);
+ if (rxrpc_check_tx_space(call, &tx_win))
+ return 0;
+
+ if (call->state >= RXRPC_CALL_COMPLETE)
+ return call->error;
+
+ if (timeout == 0 &&
+ tx_win == tx_start && signal_pending(current))
+ return -EINTR;
+
+ if (tx_win != tx_start) {
+ timeout = rtt;
+ tx_start = tx_win;
+ }
+
+ trace_rxrpc_transmit(call, rxrpc_transmit_wait);
+ timeout = schedule_timeout(timeout);
+ }
+}
+
+/*
+ * Wait for space to appear in the Tx queue uninterruptibly.
+ */
+static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
+ struct rxrpc_call *call,
+ long *timeo)
+{
+ for (;;) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (rxrpc_check_tx_space(call, NULL))
+ return 0;
+
+ if (call->state >= RXRPC_CALL_COMPLETE)
+ return call->error;
+
+ trace_rxrpc_transmit(call, rxrpc_transmit_wait);
+ *timeo = schedule_timeout(*timeo);
+ }
+}
+
+/*
+ * wait for space to appear in the transmit/ACK window
+ * - caller holds the socket locked
+ */
+static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
+ struct rxrpc_call *call,
+ long *timeo,
+ bool waitall)
+{
+ DECLARE_WAITQUEUE(myself, current);
+ int ret;
+
+ _enter(",{%u,%u,%u}",
+ call->tx_hard_ack, call->tx_top, call->tx_winsize);
+
+ add_wait_queue(&call->waitq, &myself);
+
+ switch (call->interruptibility) {
+ case RXRPC_INTERRUPTIBLE:
+ if (waitall)
+ ret = rxrpc_wait_for_tx_window_waitall(rx, call);
+ else
+ ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
+ break;
+ case RXRPC_PREINTERRUPTIBLE:
+ case RXRPC_UNINTERRUPTIBLE:
+ default:
+ ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
+ break;
+ }
+
+ remove_wait_queue(&call->waitq, &myself);
+ set_current_state(TASK_RUNNING);
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * Schedule an instant Tx resend.
+ */
+static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
+{
+ spin_lock_bh(&call->lock);
+
+ if (call->state < RXRPC_CALL_COMPLETE) {
+ call->rxtx_annotations[ix] =
+ (call->rxtx_annotations[ix] & RXRPC_TX_ANNO_LAST) |
+ RXRPC_TX_ANNO_RETRANS;
+ if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
+ rxrpc_queue_call(call);
+ }
+
+ spin_unlock_bh(&call->lock);
+}
+
+/*
+ * 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. Returns the error from rxrpc_send_data_packet()
+ * in case the caller wants to do something with it.
+ */
+static int 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);
+ unsigned long now;
+ rxrpc_seq_t seq = sp->hdr.seq;
+ int ret, ix;
+ u8 annotation = RXRPC_TX_ANNO_UNACK;
+
+ _net("queue skb %p [%d]", skb, seq);
+
+ ASSERTCMP(seq, ==, call->tx_top + 1);
+
+ if (last)
+ annotation |= RXRPC_TX_ANNO_LAST;
+
+ /* We have to set the timestamp before queueing as the retransmit
+ * algorithm can see the packet as soon as we queue it.
+ */
+ skb->tstamp = ktime_get_real();
+
+ ix = seq & RXRPC_RXTX_BUFF_MASK;
+ rxrpc_get_skb(skb, rxrpc_skb_got);
+ call->rxtx_annotations[ix] = annotation;
+ smp_wmb();
+ call->rxtx_buffer[ix] = skb;
+ call->tx_top = seq;
+ if (last)
+ trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
+ else
+ trace_rxrpc_transmit(call, rxrpc_transmit_queue);
+
+ if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
+ _debug("________awaiting reply/ACK__________");
+ write_lock_bh(&call->state_lock);
+ 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;
+ now = jiffies;
+ WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
+ if (call->ackr_reason == RXRPC_ACK_DELAY)
+ call->ackr_reason = 0;
+ trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
+ if (!last)
+ break;
+ fallthrough;
+ 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;
+ }
+ write_unlock_bh(&call->state_lock);
+ }
+
+ if (seq == 1 && rxrpc_is_client_call(call))
+ rxrpc_expose_client_call(call);
+
+ ret = rxrpc_send_data_packet(call, skb, false);
+ if (ret < 0) {
+ switch (ret) {
+ case -ENETUNREACH:
+ case -EHOSTUNREACH:
+ case -ECONNREFUSED:
+ rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
+ 0, ret);
+ goto out;
+ }
+ _debug("need instant resend %d", ret);
+ rxrpc_instant_resend(call, ix);
+ } else {
+ unsigned long now = jiffies;
+ unsigned long resend_at = now + call->peer->rto_j;
+
+ WRITE_ONCE(call->resend_at, resend_at);
+ rxrpc_reduce_call_timer(call, resend_at, now,
+ rxrpc_timer_set_for_send);
+ }
+
+out:
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * send data through a socket
+ * - must be called in process context
+ * - The caller holds the call user access mutex, but not the socket lock.
+ */
+static int rxrpc_send_data(struct rxrpc_sock *rx,
+ struct rxrpc_call *call,
+ struct msghdr *msg, size_t len,
+ rxrpc_notify_end_tx_t notify_end_tx,
+ bool *_dropped_lock)
+{
+ struct rxrpc_skb_priv *sp;
+ struct sk_buff *skb;
+ struct sock *sk = &rx->sk;
+ enum rxrpc_call_state state;
+ long timeo;
+ bool more = msg->msg_flags & MSG_MORE;
+ int ret, copied = 0;
+
+ timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
+
+ /* this should be in poll */
+ sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
+
+reload:
+ ret = -EPIPE;
+ if (sk->sk_shutdown & SEND_SHUTDOWN)
+ goto maybe_error;
+ state = READ_ONCE(call->state);
+ ret = -ESHUTDOWN;
+ if (state >= RXRPC_CALL_COMPLETE)
+ goto maybe_error;
+ ret = -EPROTO;
+ if (state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
+ state != RXRPC_CALL_SERVER_ACK_REQUEST &&
+ state != RXRPC_CALL_SERVER_SEND_REPLY)
+ goto maybe_error;
+
+ ret = -EMSGSIZE;
+ if (call->tx_total_len != -1) {
+ if (len - copied > call->tx_total_len)
+ goto maybe_error;
+ if (!more && len - copied != call->tx_total_len)
+ goto maybe_error;
+ }
+
+ skb = call->tx_pending;
+ call->tx_pending = NULL;
+ rxrpc_see_skb(skb, rxrpc_skb_seen);
+
+ do {
+ /* Check to see if there's a ping ACK to reply to. */
+ if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
+ rxrpc_send_ack_packet(call, false, NULL);
+
+ if (!skb) {
+ size_t remain, bufsize, chunk, offset;
+
+ _debug("alloc");
+
+ if (!rxrpc_check_tx_space(call, NULL))
+ goto wait_for_space;
+
+ /* Work out the maximum size of a packet. Assume that
+ * the security header is going to be in the padded
+ * region (enc blocksize), but the trailer is not.
+ */
+ remain = more ? INT_MAX : msg_data_left(msg);
+ ret = call->conn->security->how_much_data(call, remain,
+ &bufsize, &chunk, &offset);
+ if (ret < 0)
+ goto maybe_error;
+
+ _debug("SIZE: %zu/%zu @%zu", chunk, bufsize, offset);
+
+ /* create a buffer that we can retain until it's ACK'd */
+ skb = sock_alloc_send_skb(
+ sk, bufsize, msg->msg_flags & MSG_DONTWAIT, &ret);
+ if (!skb)
+ goto maybe_error;
+
+ sp = rxrpc_skb(skb);
+ sp->rx_flags |= RXRPC_SKB_TX_BUFFER;
+ rxrpc_new_skb(skb, rxrpc_skb_new);
+
+ _debug("ALLOC SEND %p", skb);
+
+ ASSERTCMP(skb->mark, ==, 0);
+
+ __skb_put(skb, offset);
+
+ sp->remain = chunk;
+ if (sp->remain > skb_tailroom(skb))
+ sp->remain = skb_tailroom(skb);
+
+ _net("skb: hr %d, tr %d, hl %d, rm %d",
+ skb_headroom(skb),
+ skb_tailroom(skb),
+ skb_headlen(skb),
+ sp->remain);
+
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ }
+
+ _debug("append");
+ sp = rxrpc_skb(skb);
+
+ /* append next segment of data to the current buffer */
+ if (msg_data_left(msg) > 0) {
+ int copy = skb_tailroom(skb);
+ ASSERTCMP(copy, >, 0);
+ if (copy > msg_data_left(msg))
+ copy = msg_data_left(msg);
+ if (copy > sp->remain)
+ copy = sp->remain;
+
+ _debug("add");
+ ret = skb_add_data(skb, &msg->msg_iter, copy);
+ _debug("added");
+ if (ret < 0)
+ goto efault;
+ sp->remain -= copy;
+ skb->mark += copy;
+ copied += copy;
+ if (call->tx_total_len != -1)
+ 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)) {
+ struct rxrpc_connection *conn = call->conn;
+ uint32_t seq;
+
+ seq = call->tx_top + 1;
+
+ sp->hdr.seq = seq;
+ sp->hdr._rsvd = 0;
+ sp->hdr.flags = conn->out_clientflag;
+
+ if (msg_data_left(msg) == 0 && !more)
+ sp->hdr.flags |= RXRPC_LAST_PACKET;
+ else if (call->tx_top - call->tx_hard_ack <
+ call->tx_winsize)
+ sp->hdr.flags |= RXRPC_MORE_PACKETS;
+
+ ret = call->security->secure_packet(call, skb, skb->mark);
+ if (ret < 0)
+ goto out;
+
+ ret = rxrpc_queue_packet(rx, call, skb,
+ !msg_data_left(msg) && !more,
+ notify_end_tx);
+ /* Should check for failure here */
+ skb = NULL;
+ }
+ } while (msg_data_left(msg) > 0);
+
+success:
+ ret = copied;
+ if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE) {
+ read_lock_bh(&call->state_lock);
+ if (call->error < 0)
+ ret = call->error;
+ read_unlock_bh(&call->state_lock);
+ }
+out:
+ call->tx_pending = skb;
+ _leave(" = %d", ret);
+ return ret;
+
+call_terminated:
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
+ _leave(" = %d", call->error);
+ return call->error;
+
+maybe_error:
+ if (copied)
+ goto success;
+ goto out;
+
+efault:
+ ret = -EFAULT;
+ goto out;
+
+wait_for_space:
+ ret = -EAGAIN;
+ if (msg->msg_flags & MSG_DONTWAIT)
+ goto maybe_error;
+ mutex_unlock(&call->user_mutex);
+ *_dropped_lock = true;
+ ret = rxrpc_wait_for_tx_window(rx, call, &timeo,
+ msg->msg_flags & MSG_WAITALL);
+ if (ret < 0)
+ goto maybe_error;
+ if (call->interruptibility == RXRPC_INTERRUPTIBLE) {
+ if (mutex_lock_interruptible(&call->user_mutex) < 0) {
+ ret = sock_intr_errno(timeo);
+ goto maybe_error;
+ }
+ } else {
+ mutex_lock(&call->user_mutex);
+ }
+ *_dropped_lock = false;
+ goto reload;
+}
+
+/*
+ * extract control messages from the sendmsg() control buffer
+ */
+static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
+{
+ struct cmsghdr *cmsg;
+ bool got_user_ID = false;
+ int len;
+
+ if (msg->msg_controllen == 0)
+ return -EINVAL;
+
+ for_each_cmsghdr(cmsg, msg) {
+ if (!CMSG_OK(msg, cmsg))
+ return -EINVAL;
+
+ len = cmsg->cmsg_len - sizeof(struct cmsghdr);
+ _debug("CMSG %d, %d, %d",
+ cmsg->cmsg_level, cmsg->cmsg_type, len);
+
+ if (cmsg->cmsg_level != SOL_RXRPC)
+ continue;
+
+ switch (cmsg->cmsg_type) {
+ case RXRPC_USER_CALL_ID:
+ if (msg->msg_flags & MSG_CMSG_COMPAT) {
+ if (len != sizeof(u32))
+ return -EINVAL;
+ p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
+ } else {
+ if (len != sizeof(unsigned long))
+ return -EINVAL;
+ p->call.user_call_ID = *(unsigned long *)
+ CMSG_DATA(cmsg);
+ }
+ got_user_ID = true;
+ break;
+
+ case RXRPC_ABORT:
+ if (p->command != RXRPC_CMD_SEND_DATA)
+ return -EINVAL;
+ p->command = RXRPC_CMD_SEND_ABORT;
+ if (len != sizeof(p->abort_code))
+ return -EINVAL;
+ p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
+ if (p->abort_code == 0)
+ return -EINVAL;
+ break;
+
+ case RXRPC_CHARGE_ACCEPT:
+ if (p->command != RXRPC_CMD_SEND_DATA)
+ return -EINVAL;
+ p->command = RXRPC_CMD_CHARGE_ACCEPT;
+ if (len != 0)
+ return -EINVAL;
+ break;
+
+ case RXRPC_EXCLUSIVE_CALL:
+ p->exclusive = true;
+ if (len != 0)
+ return -EINVAL;
+ break;
+
+ case RXRPC_UPGRADE_SERVICE:
+ p->upgrade = true;
+ if (len != 0)
+ return -EINVAL;
+ break;
+
+ case RXRPC_TX_LENGTH:
+ if (p->call.tx_total_len != -1 || len != sizeof(__s64))
+ return -EINVAL;
+ p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
+ if (p->call.tx_total_len < 0)
+ return -EINVAL;
+ break;
+
+ case RXRPC_SET_CALL_TIMEOUT:
+ if (len & 3 || len < 4 || len > 12)
+ return -EINVAL;
+ memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
+ p->call.nr_timeouts = len / 4;
+ if (p->call.timeouts.hard > INT_MAX / HZ)
+ return -ERANGE;
+ if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
+ return -ERANGE;
+ if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
+ return -ERANGE;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ if (!got_user_ID)
+ return -EINVAL;
+ if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
+ return -EINVAL;
+ _leave(" = 0");
+ return 0;
+}
+
+/*
+ * Create a new client call for sendmsg().
+ * - Called with the socket lock held, which it must release.
+ * - If it returns a call, the call's lock will need releasing by the caller.
+ */
+static struct rxrpc_call *
+rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
+ struct rxrpc_send_params *p)
+ __releases(&rx->sk.sk_lock.slock)
+ __acquires(&call->user_mutex)
+{
+ struct rxrpc_conn_parameters cp;
+ struct rxrpc_call *call;
+ struct key *key;
+
+ DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
+
+ _enter("");
+
+ if (!msg->msg_name) {
+ release_sock(&rx->sk);
+ return ERR_PTR(-EDESTADDRREQ);
+ }
+
+ key = rx->key;
+ if (key && !rx->key->payload.data[0])
+ key = NULL;
+
+ memset(&cp, 0, sizeof(cp));
+ cp.local = rx->local;
+ cp.key = rx->key;
+ cp.security_level = rx->min_sec_level;
+ cp.exclusive = rx->exclusive | p->exclusive;
+ cp.upgrade = p->upgrade;
+ cp.service_id = srx->srx_service;
+ call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
+ atomic_inc_return(&rxrpc_debug_id));
+ /* The socket is now unlocked */
+
+ rxrpc_put_peer(cp.peer);
+ _leave(" = %p\n", call);
+ return call;
+}
+
+/*
+ * send a message forming part of a client call through an RxRPC socket
+ * - caller holds the socket locked
+ * - the socket may be either a client socket or a server socket
+ */
+int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
+ __releases(&rx->sk.sk_lock.slock)
+ __releases(&call->user_mutex)
+{
+ enum rxrpc_call_state state;
+ struct rxrpc_call *call;
+ unsigned long now, j;
+ bool dropped_lock = false;
+ int ret;
+
+ struct rxrpc_send_params p = {
+ .call.tx_total_len = -1,
+ .call.user_call_ID = 0,
+ .call.nr_timeouts = 0,
+ .call.interruptibility = RXRPC_INTERRUPTIBLE,
+ .abort_code = 0,
+ .command = RXRPC_CMD_SEND_DATA,
+ .exclusive = false,
+ .upgrade = false,
+ };
+
+ _enter("");
+
+ ret = rxrpc_sendmsg_cmsg(msg, &p);
+ if (ret < 0)
+ goto error_release_sock;
+
+ if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
+ ret = -EINVAL;
+ if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
+ goto error_release_sock;
+ ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
+ goto error_release_sock;
+ }
+
+ call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
+ if (!call) {
+ ret = -EBADSLT;
+ if (p.command != RXRPC_CMD_SEND_DATA)
+ goto error_release_sock;
+ call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
+ /* The socket is now unlocked... */
+ if (IS_ERR(call))
+ return PTR_ERR(call);
+ /* ... and we have the call lock. */
+ ret = 0;
+ if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE)
+ goto out_put_unlock;
+ } else {
+ switch (READ_ONCE(call->state)) {
+ case RXRPC_CALL_UNINITIALISED:
+ case RXRPC_CALL_CLIENT_AWAIT_CONN:
+ case RXRPC_CALL_SERVER_PREALLOC:
+ case RXRPC_CALL_SERVER_SECURING:
+ rxrpc_put_call(call, rxrpc_call_put);
+ ret = -EBUSY;
+ goto error_release_sock;
+ default:
+ break;
+ }
+
+ ret = mutex_lock_interruptible(&call->user_mutex);
+ release_sock(&rx->sk);
+ if (ret < 0) {
+ ret = -ERESTARTSYS;
+ goto error_put;
+ }
+
+ if (p.call.tx_total_len != -1) {
+ ret = -EINVAL;
+ if (call->tx_total_len != -1 ||
+ call->tx_pending ||
+ call->tx_top != 0)
+ goto out_put_unlock;
+ call->tx_total_len = p.call.tx_total_len;
+ }
+ }
+
+ switch (p.call.nr_timeouts) {
+ case 3:
+ j = msecs_to_jiffies(p.call.timeouts.normal);
+ if (p.call.timeouts.normal > 0 && j == 0)
+ j = 1;
+ WRITE_ONCE(call->next_rx_timo, j);
+ fallthrough;
+ case 2:
+ j = msecs_to_jiffies(p.call.timeouts.idle);
+ if (p.call.timeouts.idle > 0 && j == 0)
+ j = 1;
+ WRITE_ONCE(call->next_req_timo, j);
+ fallthrough;
+ case 1:
+ if (p.call.timeouts.hard > 0) {
+ j = p.call.timeouts.hard * HZ;
+ now = jiffies;
+ j += now;
+ WRITE_ONCE(call->expect_term_by, j);
+ rxrpc_reduce_call_timer(call, j, now,
+ rxrpc_timer_set_for_hard);
+ }
+ break;
+ }
+
+ state = READ_ONCE(call->state);
+ _debug("CALL %d USR %lx ST %d on CONN %p",
+ call->debug_id, call->user_call_ID, state, call->conn);
+
+ if (state >= RXRPC_CALL_COMPLETE) {
+ /* it's too late for this call */
+ ret = -ESHUTDOWN;
+ } else if (p.command == RXRPC_CMD_SEND_ABORT) {
+ ret = 0;
+ if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
+ ret = rxrpc_send_abort_packet(call);
+ } else if (p.command != RXRPC_CMD_SEND_DATA) {
+ ret = -EINVAL;
+ } else {
+ ret = rxrpc_send_data(rx, call, msg, len, NULL, &dropped_lock);
+ }
+
+out_put_unlock:
+ if (!dropped_lock)
+ mutex_unlock(&call->user_mutex);
+error_put:
+ rxrpc_put_call(call, rxrpc_call_put);
+ _leave(" = %d", ret);
+ return ret;
+
+error_release_sock:
+ release_sock(&rx->sk);
+ return ret;
+}
+
+/**
+ * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
+ * @sock: The socket the call is on
+ * @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,
+ * nor should an address be supplied. MSG_MORE should be flagged if there's
+ * 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,
+ rxrpc_notify_end_tx_t notify_end_tx)
+{
+ bool dropped_lock = false;
+ int ret;
+
+ _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
+
+ ASSERTCMP(msg->msg_name, ==, NULL);
+ ASSERTCMP(msg->msg_control, ==, NULL);
+
+ mutex_lock(&call->user_mutex);
+
+ _debug("CALL %d USR %lx ST %d on CONN %p",
+ call->debug_id, call->user_call_ID, call->state, call->conn);
+
+ switch (READ_ONCE(call->state)) {
+ 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,
+ notify_end_tx, &dropped_lock);
+ break;
+ case RXRPC_CALL_COMPLETE:
+ read_lock_bh(&call->state_lock);
+ ret = call->error;
+ read_unlock_bh(&call->state_lock);
+ break;
+ default:
+ /* Request phase complete for this client call */
+ trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
+ ret = -EPROTO;
+ break;
+ }
+
+ if (!dropped_lock)
+ mutex_unlock(&call->user_mutex);
+ _leave(" = %d", ret);
+ return ret;
+}
+EXPORT_SYMBOL(rxrpc_kernel_send_data);
+
+/**
+ * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
+ * @sock: The socket the call is on
+ * @call: The call to be aborted
+ * @abort_code: The abort code to stick into the ABORT packet
+ * @error: Local error value
+ * @why: 3-char string indicating why.
+ *
+ * Allow a kernel service to abort a call, if it's still in an abortable state
+ * and return true if the call was aborted, false if it was already complete.
+ */
+bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
+ u32 abort_code, int error, const char *why)
+{
+ bool aborted;
+
+ _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
+
+ mutex_lock(&call->user_mutex);
+
+ aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
+ if (aborted)
+ rxrpc_send_abort_packet(call);
+
+ mutex_unlock(&call->user_mutex);
+ return aborted;
+}
+EXPORT_SYMBOL(rxrpc_kernel_abort_call);
+
+/**
+ * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
+ * @sock: The socket the call is on
+ * @call: The call to be informed
+ * @tx_total_len: The amount of data to be transmitted for this call
+ *
+ * Allow a kernel service to set the total transmit length on a call. This
+ * allows buffer-to-packet encrypt-and-copy to be performed.
+ *
+ * This function is primarily for use for setting the reply length since the
+ * request length can be set when beginning the call.
+ */
+void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
+ s64 tx_total_len)
+{
+ WARN_ON(call->tx_total_len != -1);
+ call->tx_total_len = tx_total_len;
+}
+EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);