/* * Copyright (c) 2006, 2018 Oracle and/or its affiliates. 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 <linux/kernel.h> #include <linux/moduleparam.h> #include <linux/gfp.h> #include <net/sock.h> #include <linux/in.h> #include <linux/list.h> #include <linux/ratelimit.h> #include <linux/export.h> #include <linux/sizes.h>
#include"rds.h"
/* When transmitting messages in rds_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).
*/ staticint send_batch_count = SZ_1K;
module_param(send_batch_count, int, 0444);
MODULE_PARM_DESC(send_batch_count, " batch factor when working the send queue");
staticvoid rds_send_remove_from_sock(struct list_head *messages, int status);
/* * Reset the send state. Callers must ensure that this doesn't race with * rds_send_xmit().
*/ void rds_send_path_reset(struct rds_conn_path *cp)
{ struct rds_message *rm, *tmp; unsignedlong flags;
if (cp->cp_xmit_rm) {
rm = cp->cp_xmit_rm;
cp->cp_xmit_rm = NULL; /* 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 */
rds_message_unmapped(rm);
rds_message_put(rm);
}
staticvoid release_in_xmit(struct rds_conn_path *cp)
{
clear_bit_unlock(RDS_IN_XMIT, &cp->cp_flags); /* * We don't use wait_on_bit()/wake_up_bit() because our waking is in a * hot path and finding waiters is very rare. We don't want to walk * the system-wide hashed waitqueue buckets in the fast path only to * almost never find waiters.
*/ if (waitqueue_active(&cp->cp_waitq))
wake_up_all(&cp->cp_waitq);
}
/* * We're making the conscious 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 rds_send_xmit(struct rds_conn_path *cp)
{ struct rds_connection *conn = cp->cp_conn; struct rds_message *rm; unsignedlong flags; unsignedint tmp; struct scatterlist *sg; int ret = 0;
LIST_HEAD(to_be_dropped); int batch_count; unsignedlong send_gen = 0; int same_rm = 0;
restart:
batch_count = 0;
/* * 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 (!acquire_in_xmit(cp)) {
rds_stats_inc(s_send_lock_contention);
ret = -ENOMEM; goto out;
}
if (rds_destroy_pending(cp->cp_conn)) {
release_in_xmit(cp);
ret = -ENETUNREACH; /* dont requeue send work */ goto out;
}
/* * we record the send generation after doing the xmit acquire. * if someone else manages to jump in and do some work, we'll use * this to avoid a goto restart farther down. * * The acquire_in_xmit() check above ensures that only one * caller can increment c_send_gen at any time.
*/
send_gen = READ_ONCE(cp->cp_send_gen) + 1;
WRITE_ONCE(cp->cp_send_gen, send_gen);
/* * rds_conn_shutdown() sets the conn state and then tests RDS_IN_XMIT, * we do the opposite to avoid races.
*/ if (!rds_conn_path_up(cp)) {
release_in_xmit(cp);
ret = 0; goto out;
}
if (conn->c_trans->xmit_path_prepare)
conn->c_trans->xmit_path_prepare(cp);
/* * spin trying to push headers and data down the connection until * the connection doesn't make forward progress.
*/ while (1) {
rm = cp->cp_xmit_rm;
if (!rm) {
same_rm = 0;
} else {
same_rm++; if (same_rm >= 4096) {
rds_stats_inc(s_send_stuck_rm);
ret = -EAGAIN; break;
}
}
/* * If between sending messages, we can send a pending congestion * map update.
*/ if (!rm && test_and_clear_bit(0, &conn->c_map_queued)) {
rm = rds_cong_update_alloc(conn); if (IS_ERR(rm)) {
ret = PTR_ERR(rm); break;
}
rm->data.op_active = 1;
rm->m_inc.i_conn_path = cp;
rm->m_inc.i_conn = cp->cp_conn;
cp->cp_xmit_rm = rm;
}
/* * If not already working on one, grab the next message. * * cp_xmit_rm holds a ref while we're sending this message down * the connection. We can use this ref while holding the * send_sem.. rds_send_reset() is serialized with it.
*/ if (!rm) { unsignedint len;
batch_count++;
/* we want to process as big a batch as we can, but * we also want to avoid softlockups. If we've been * through a lot of messages, lets back off and see * if anyone else jumps in
*/ if (batch_count >= send_batch_count) goto over_batch;
spin_lock_irqsave(&cp->cp_lock, flags);
if (!list_empty(&cp->cp_send_queue)) {
rm = list_entry(cp->cp_send_queue.next, struct rds_message,
m_conn_item);
rds_message_addref(rm);
/* * Move the message from the send queue to the retransmit * list right away.
*/
list_move_tail(&rm->m_conn_item,
&cp->cp_retrans);
}
spin_unlock_irqrestore(&cp->cp_lock, flags);
if (!rm) break;
/* Unfortunately, the way Infiniband deals with * RDMA to a bad MR key is by moving the entire * queue pair to error state. We could possibly * recover from that, but right now we drop the * connection. * Therefore, we never retransmit messages with RDMA ops.
*/ if (test_bit(RDS_MSG_FLUSH, &rm->m_flags) ||
(rm->rdma.op_active &&
test_bit(RDS_MSG_RETRANSMITTED, &rm->m_flags))) {
spin_lock_irqsave(&cp->cp_lock, flags); if (test_and_clear_bit(RDS_MSG_ON_CONN, &rm->m_flags))
list_move(&rm->m_conn_item, &to_be_dropped);
spin_unlock_irqrestore(&cp->cp_lock, flags); continue;
}
/* Require an ACK every once in a while */
len = ntohl(rm->m_inc.i_hdr.h_len); if (cp->cp_unacked_packets == 0 ||
cp->cp_unacked_bytes < len) {
set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags);
/* The transport either sends the whole rdma or none of it */ if (rm->rdma.op_active && !cp->cp_xmit_rdma_sent) {
rm->m_final_op = &rm->rdma; /* The transport owns the mapped memory for now. * You can't unmap it while it's on the send queue
*/
set_bit(RDS_MSG_MAPPED, &rm->m_flags);
ret = conn->c_trans->xmit_rdma(conn, &rm->rdma); if (ret) {
clear_bit(RDS_MSG_MAPPED, &rm->m_flags);
wake_up_interruptible(&rm->m_flush_wait); break;
}
cp->cp_xmit_rdma_sent = 1;
}
if (rm->atomic.op_active && !cp->cp_xmit_atomic_sent) {
rm->m_final_op = &rm->atomic; /* The transport owns the mapped memory for now. * You can't unmap it while it's on the send queue
*/
set_bit(RDS_MSG_MAPPED, &rm->m_flags);
ret = conn->c_trans->xmit_atomic(conn, &rm->atomic); if (ret) {
clear_bit(RDS_MSG_MAPPED, &rm->m_flags);
wake_up_interruptible(&rm->m_flush_wait); break;
}
cp->cp_xmit_atomic_sent = 1;
}
/* * A number of cases require an RDS header to be sent * even if there is no data. * We permit 0-byte sends; rds-ping depends on this. * However, if there are exclusively attached silent ops, * we skip the hdr/data send, to enable silent operation.
*/ if (rm->data.op_nents == 0) { int ops_present; int all_ops_are_silent = 1;
ops_present = (rm->atomic.op_active || rm->rdma.op_active); if (rm->atomic.op_active && !rm->atomic.op_silent)
all_ops_are_silent = 0; if (rm->rdma.op_active && !rm->rdma.op_silent)
all_ops_are_silent = 0;
if (ops_present && all_ops_are_silent
&& !rm->m_rdma_cookie)
rm->data.op_active = 0;
}
if (rm->data.op_active && !cp->cp_xmit_data_sent) {
rm->m_final_op = &rm->data;
ret = conn->c_trans->xmit(conn, rm,
cp->cp_xmit_hdr_off,
cp->cp_xmit_sg,
cp->cp_xmit_data_off); if (ret <= 0) break;
/* * A rm will only take multiple times through this loop * if there is a data op. Thus, if the data is sent (or there was * none), then we're done with the rm.
*/ if (!rm->data.op_active || cp->cp_xmit_data_sent) {
cp->cp_xmit_rm = NULL;
cp->cp_xmit_sg = 0;
cp->cp_xmit_hdr_off = 0;
cp->cp_xmit_data_off = 0;
cp->cp_xmit_rdma_sent = 0;
cp->cp_xmit_atomic_sent = 0;
cp->cp_xmit_data_sent = 0;
rds_message_put(rm);
}
}
over_batch: if (conn->c_trans->xmit_path_complete)
conn->c_trans->xmit_path_complete(cp);
release_in_xmit(cp);
/* Nuke any messages we decided not to retransmit. */ if (!list_empty(&to_be_dropped)) { /* irqs on here, so we can put(), unlike above */
list_for_each_entry(rm, &to_be_dropped, m_conn_item)
rds_message_put(rm);
rds_send_remove_from_sock(&to_be_dropped, RDS_RDMA_DROPPED);
}
/* * Other senders can queue a message after we last test the send queue * but before we clear RDS_IN_XMIT. In that case they'd back off and * not try and send their newly queued message. We need to check the * send queue after having cleared RDS_IN_XMIT so that their message * doesn't get stuck on the send queue. * * If the transport cannot continue (i.e ret != 0), then it must * call us when more room is available, such as from the tx * completion handler. * * We have an extra generation check here so that if someone manages * to jump in after our release_in_xmit, we'll see that they have done * some work and we will skip our goto
*/ if (ret == 0) { bool raced;
/* * 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 rds_rdma_send_complete(struct rds_message *rm, int status)
{ struct rds_sock *rs = NULL; struct rm_rdma_op *ro; struct rds_notifier *notifier; unsignedlong flags;
if (rs) {
rds_wake_sk_sleep(rs);
sock_put(rds_rs_to_sk(rs));
}
}
EXPORT_SYMBOL_GPL(rds_atomic_send_complete);
/* * This is the same as rds_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.
*/ staticinlinevoid
__rds_send_complete(struct rds_sock *rs, struct rds_message *rm, int status)
{ struct rm_rdma_op *ro; struct rm_atomic_op *ao;
ao = &rm->atomic; if (ao->op_active && ao->op_notify && ao->op_notifier) {
ao->op_notifier->n_status = status;
list_add_tail(&ao->op_notifier->n_list, &rs->rs_notify_queue);
ao->op_notifier = NULL;
}
/* No need to wake the app - caller does this */
}
/* * 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.
*/ staticvoid rds_send_remove_from_sock(struct list_head *messages, int status)
{ unsignedlong flags; struct rds_sock *rs = NULL; struct rds_message *rm;
while (!list_empty(messages)) { int was_on_sock = 0;
/* * 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.
*/
spin_lock_irqsave(&rm->m_rs_lock, flags); if (!test_bit(RDS_MSG_ON_SOCK, &rm->m_flags)) goto unlock_and_drop;
if (rs != rm->m_rs) { if (rs) {
rds_wake_sk_sleep(rs);
sock_put(rds_rs_to_sk(rs));
}
rs = rm->m_rs; if (rs)
sock_hold(rds_rs_to_sk(rs));
} if (!rs) goto unlock_and_drop;
spin_lock(&rs->rs_lock);
unlock_and_drop:
spin_unlock_irqrestore(&rm->m_rs_lock, flags);
rds_message_put(rm); if (was_on_sock)
rds_message_put(rm);
}
if (rs) {
rds_wake_sk_sleep(rs);
sock_put(rds_rs_to_sk(rs));
}
}
/* * 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 rds_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 RDS_MSG_HAS_ACK_SEQ bit.
*/ void rds_send_path_drop_acked(struct rds_conn_path *cp, u64 ack,
is_acked_func is_acked)
{ struct rds_message *rm, *tmp; unsignedlong flags;
LIST_HEAD(list);
spin_lock_irqsave(&cp->cp_lock, flags);
list_for_each_entry_safe(rm, tmp, &cp->cp_retrans, m_conn_item) { if (!rds_send_is_acked(rm, ack, is_acked)) break;
/* order flag updates with spin locks */ if (!list_empty(&list))
smp_mb__after_atomic();
spin_unlock_irqrestore(&cp->cp_lock, flags);
/* now remove the messages from the sock list as needed */
rds_send_remove_from_sock(&list, RDS_RDMA_SUCCESS);
}
EXPORT_SYMBOL_GPL(rds_send_path_drop_acked);
spin_lock_irqsave(&cp->cp_lock, flags); /* * Maybe someone else beat us to removing rm 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_and_clear_bit(RDS_MSG_ON_CONN, &rm->m_flags)) {
spin_unlock_irqrestore(&cp->cp_lock, flags); continue;
}
list_del_init(&rm->m_conn_item);
spin_unlock_irqrestore(&cp->cp_lock, flags);
/* * Couldn't grab m_rs_lock in top loop (lock ordering), * but we can now.
*/
spin_lock_irqsave(&rm->m_rs_lock, flags);
/* just in case the code above skipped this message * because RDS_MSG_ON_CONN wasn't set, run it again here * taking m_rs_lock is the only thing that keeps us * from racing with ack processing.
*/
spin_lock_irqsave(&rm->m_rs_lock, flags);
/* * 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 RDS_CANCEL_SENT_TO.
*/ staticint rds_send_queue_rm(struct rds_sock *rs, struct rds_connection *conn, struct rds_conn_path *cp, struct rds_message *rm, __be16 sport,
__be16 dport, int *queued)
{ unsignedlong flags;
u32 len;
if (*queued) goto out;
len = be32_to_cpu(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 */
spin_lock_irqsave(&rs->rs_lock, flags);
/* * 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 < rds_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 >= rds_sk_sndbuf(rs) / 2)
set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags);
/* The code ordering is a little weird, but we're
trying to minimize the time we hold c_lock */
rds_message_populate_header(&rm->m_inc.i_hdr, sport, dport, 0);
rm->m_inc.i_conn = conn;
rm->m_inc.i_conn_path = cp;
rds_message_addref(rm);
/* * rds_message is getting to be quite complicated, and we'd like to allocate * it all in one go. This figures out how big it needs to be up front.
*/ staticint rds_rm_size(struct msghdr *msg, int num_sgs, struct rds_iov_vector_arr *vct)
{ struct cmsghdr *cmsg; int size = 0; int cmsg_groups = 0; int retval; bool zcopy_cookie = false; struct rds_iov_vector *iov, *tmp_iov;
if (num_sgs < 0) return -EINVAL;
for_each_cmsghdr(cmsg, msg) { if (!CMSG_OK(msg, cmsg)) return -EINVAL;
case RDS_CMSG_ZCOPY_COOKIE:
zcopy_cookie = true;
fallthrough;
case RDS_CMSG_RDMA_DEST: case RDS_CMSG_RDMA_MAP:
cmsg_groups |= 2; /* these are valid but do no add any size */ break;
case RDS_CMSG_ATOMIC_CSWP: case RDS_CMSG_ATOMIC_FADD: case RDS_CMSG_MASKED_ATOMIC_CSWP: case RDS_CMSG_MASKED_ATOMIC_FADD:
cmsg_groups |= 1;
size += sizeof(struct scatterlist); break;
default: return -EINVAL;
}
}
if ((msg->msg_flags & MSG_ZEROCOPY) && !zcopy_cookie) return -EINVAL;
size += num_sgs * sizeof(struct scatterlist);
/* Ensure (DEST, MAP) are never used with (ARGS, ATOMIC) */ if (cmsg_groups == 3) return -EINVAL;
staticint rds_cmsg_send(struct rds_sock *rs, struct rds_message *rm, struct msghdr *msg, int *allocated_mr, struct rds_iov_vector_arr *vct)
{ struct cmsghdr *cmsg; int ret = 0, ind = 0;
for_each_cmsghdr(cmsg, msg) { if (!CMSG_OK(msg, cmsg)) return -EINVAL;
if (cmsg->cmsg_level != SOL_RDS) continue;
/* As a side effect, RDMA_DEST and RDMA_MAP will set * rm->rdma.m_rdma_cookie and rm->rdma.m_rdma_mr.
*/ switch (cmsg->cmsg_type) { case RDS_CMSG_RDMA_ARGS: if (ind >= vct->indx) return -ENOMEM;
ret = rds_cmsg_rdma_args(rs, rm, cmsg, &vct->vec[ind]);
ind++; break;
case RDS_CMSG_RDMA_DEST:
ret = rds_cmsg_rdma_dest(rs, rm, cmsg); break;
case RDS_CMSG_RDMA_MAP:
ret = rds_cmsg_rdma_map(rs, rm, cmsg); if (!ret)
*allocated_mr = 1; elseif (ret == -ENODEV) /* Accommodate the get_mr() case which can fail * if connection isn't established yet.
*/
ret = -EAGAIN; break; case RDS_CMSG_ATOMIC_CSWP: case RDS_CMSG_ATOMIC_FADD: case RDS_CMSG_MASKED_ATOMIC_CSWP: case RDS_CMSG_MASKED_ATOMIC_FADD:
ret = rds_cmsg_atomic(rs, rm, cmsg); break;
case RDS_CMSG_ZCOPY_COOKIE:
ret = rds_cmsg_zcopy(rs, rm, cmsg); break;
default: return -EINVAL;
}
if (ret) break;
}
return ret;
}
staticint rds_send_mprds_hash(struct rds_sock *rs, struct rds_connection *conn, int nonblock)
{ int hash;
/* The underlying connection is not up yet. Need to wait * until it is up to be sure that the non-zero c_path can be * used. But if we are interrupted, we have to use the zero * c_path in case the connection ends up being non-MP capable.
*/ if (conn->c_npaths == 0) { /* Cannot wait for the connection be made, so just use * the base c_path.
*/ if (nonblock) return 0; if (wait_event_interruptible(conn->c_hs_waitq,
conn->c_npaths != 0))
hash = 0;
} if (conn->c_npaths == 1)
hash = 0;
} return hash;
}
/* expect 1 RDMA CMSG per rds_sendmsg. can still grow if more needed. */
vct.incr = 1;
/* Mirror Linux UDP mirror of BSD error message compatibility */ /* XXX: Perhaps MSG_MORE someday */ if (msg->msg_flags & ~(MSG_DONTWAIT | MSG_CMSG_COMPAT | MSG_ZEROCOPY)) {
ret = -EOPNOTSUPP; goto out;
}
namelen = msg->msg_namelen; if (namelen != 0) { if (namelen < sizeof(*usin)) {
ret = -EINVAL; goto out;
} switch (usin->sin_family) { case AF_INET: if (usin->sin_addr.s_addr == htonl(INADDR_ANY) ||
usin->sin_addr.s_addr == htonl(INADDR_BROADCAST) ||
ipv4_is_multicast(usin->sin_addr.s_addr)) {
ret = -EINVAL; goto out;
}
ipv6_addr_set_v4mapped(usin->sin_addr.s_addr, &daddr);
dport = usin->sin_port; break;
#if IS_ENABLED(CONFIG_IPV6) case AF_INET6: { int addr_type;
if (namelen < sizeof(*sin6)) {
ret = -EINVAL; goto out;
}
addr_type = ipv6_addr_type(&sin6->sin6_addr); if (!(addr_type & IPV6_ADDR_UNICAST)) {
__be32 addr4;
if (!(addr_type & IPV6_ADDR_MAPPED)) {
ret = -EINVAL; goto out;
}
/* It is a mapped address. Need to do some * sanity checks.
*/
addr4 = sin6->sin6_addr.s6_addr32[3]; if (addr4 == htonl(INADDR_ANY) ||
addr4 == htonl(INADDR_BROADCAST) ||
ipv4_is_multicast(addr4)) {
ret = -EINVAL; goto out;
}
} if (addr_type & IPV6_ADDR_LINKLOCAL) { if (sin6->sin6_scope_id == 0) {
ret = -EINVAL; goto out;
}
scope_id = sin6->sin6_scope_id;
}
default:
ret = -EINVAL; goto out;
}
} else { /* We only care about consistency with ->connect() */
lock_sock(sk);
daddr = rs->rs_conn_addr;
dport = rs->rs_conn_port;
scope_id = rs->rs_bound_scope_id;
release_sock(sk);
}
lock_sock(sk); if (ipv6_addr_any(&rs->rs_bound_addr) || ipv6_addr_any(&daddr)) {
release_sock(sk);
ret = -ENOTCONN; goto out;
} elseif (namelen != 0) { /* Cannot send to an IPv4 address using an IPv6 source * address and cannot send to an IPv6 address using an * IPv4 source address.
*/ if (ipv6_addr_v4mapped(&daddr) ^
ipv6_addr_v4mapped(&rs->rs_bound_addr)) {
release_sock(sk);
ret = -EOPNOTSUPP; goto out;
} /* If the socket is already bound to a link local address, * it can only send to peers on the same link. But allow * communicating between link local and non-link local address.
*/ if (scope_id != rs->rs_bound_scope_id) { if (!scope_id) {
scope_id = rs->rs_bound_scope_id;
} elseif (rs->rs_bound_scope_id) {
release_sock(sk);
ret = -EINVAL; goto out;
}
}
}
release_sock(sk);
ret = rds_rdma_bytes(msg, &rdma_payload_len); if (ret) goto out;
if (max_t(size_t, payload_len, rdma_payload_len) > RDS_MAX_MSG_SIZE) {
ret = -EMSGSIZE; goto out;
}
if (payload_len > rds_sk_sndbuf(rs)) {
ret = -EMSGSIZE; goto out;
}
if (zcopy) { if (rs->rs_transport->t_type != RDS_TRANS_TCP) {
ret = -EOPNOTSUPP; goto out;
}
num_sgs = iov_iter_npages(&msg->msg_iter, INT_MAX);
} /* size of rm including all sgs */
ret = rds_rm_size(msg, num_sgs, &vct); if (ret < 0) goto out;
rm = rds_message_alloc(ret, GFP_KERNEL); if (!rm) {
ret = -ENOMEM; goto out;
}
/* Attach data to the rm */ if (payload_len) {
rm->data.op_sg = rds_message_alloc_sgs(rm, num_sgs); if (IS_ERR(rm->data.op_sg)) {
ret = PTR_ERR(rm->data.op_sg); goto out;
}
ret = rds_message_copy_from_user(rm, &msg->msg_iter, zcopy); if (ret) goto out;
}
rm->data.op_active = 1;
rm->m_daddr = daddr;
/* rds_conn_create has a spinlock that runs with IRQ off.
* Caching the conn in the socket helps a lot. */ if (rs->rs_conn && ipv6_addr_equal(&rs->rs_conn->c_faddr, &daddr) &&
rs->rs_tos == rs->rs_conn->c_tos) {
conn = rs->rs_conn;
} else {
conn = rds_conn_create_outgoing(sock_net(sock->sk),
&rs->rs_bound_addr, &daddr,
rs->rs_transport, rs->rs_tos,
sock->sk->sk_allocation,
scope_id); if (IS_ERR(conn)) {
ret = PTR_ERR(conn); goto out;
}
rs->rs_conn = conn;
}
ret = timeo; if (ret == 0)
ret = -ETIMEDOUT; goto out;
}
/* * By now we've committed to the send. We reuse rds_send_worker() * to retry sends in the rds thread if the transport asks us to.
*/
rds_stats_inc(s_send_queued);
ret = rds_send_xmit(cpath); if (ret == -ENOMEM || ret == -EAGAIN) {
ret = 0;
rcu_read_lock(); if (rds_destroy_pending(cpath->cp_conn))
ret = -ENETUNREACH; else
queue_delayed_work(rds_wq, &cpath->cp_send_w, 1);
rcu_read_unlock();
} if (ret) goto out;
rds_message_put(rm);
for (ind = 0; ind < vct.indx; ind++)
kfree(vct.vec[ind].iov);
kfree(vct.vec);
return payload_len;
out: for (ind = 0; ind < vct.indx; ind++)
kfree(vct.vec[ind].iov);
kfree(vct.vec);
/* 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)
rds_rdma_unuse(rs, rds_rdma_cookie_key(rm->m_rdma_cookie), 1);
if (rm)
rds_message_put(rm); return ret;
}
/* * send out a probe. Can be shared by rds_send_ping, * rds_send_pong, rds_send_hb. * rds_send_hb should use h_flags * RDS_FLAG_HB_PING|RDS_FLAG_ACK_REQUIRED * or * RDS_FLAG_HB_PONG|RDS_FLAG_ACK_REQUIRED
*/ staticint
rds_send_probe(struct rds_conn_path *cp, __be16 sport,
__be16 dport, u8 h_flags)
{ struct rds_message *rm; unsignedlong flags; int ret = 0;
rm = rds_message_alloc(0, GFP_ATOMIC); if (!rm) {
ret = -ENOMEM; goto out;
}
/* schedule the send work on rds_wq */
rcu_read_lock(); if (!rds_destroy_pending(cp->cp_conn))
queue_delayed_work(rds_wq, &cp->cp_send_w, 1);
rcu_read_unlock();
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