net_dma: simple removal

Per commit "77873803363c net_dma: mark broken" net_dma is no longer used
and there is no plan to fix it.

This is the mechanical removal of bits in CONFIG_NET_DMA ifdef guards.
Reverting the remainder of the net_dma induced changes is deferred to
subsequent patches.

Marked for stable due to Roman's report of a memory leak in
dma_pin_iovec_pages():

    https://lkml.org/lkml/2014/9/3/177

Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: David Whipple <whipple@securedatainnovations.ch>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: <stable@vger.kernel.org>
Reported-by: Roman Gushchin <klamm@yandex-team.ru>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

11 files changed, 23 insertions, 387 deletions

diff --git a/net/core/Makefile b/net/core/Makefile
index 9628c20acff6..5038f1ea0349 100644
--- a/net/core/Makefile
+++ b/net/core/Makefile
@@ -16,7 +16,6 @@ obj-y += net-sysfs.o
 obj-$(CONFIG_PROC_FS) += net-procfs.o
 obj-$(CONFIG_NET_PKTGEN) += pktgen.o
 obj-$(CONFIG_NETPOLL) += netpoll.o
-obj-$(CONFIG_NET_DMA) += user_dma.o
 obj-$(CONFIG_FIB_RULES) += fib_rules.o
 obj-$(CONFIG_TRACEPOINTS) += net-traces.o
 obj-$(CONFIG_NET_DROP_MONITOR) += drop_monitor.o
diff --git a/net/core/dev.c b/net/core/dev.c
index b1b0c8d4d7df..5e37e9abe8c5 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1266,7 +1266,6 @@ static int __dev_open(struct net_device *dev)
                 clear_bit(__LINK_STATE_START, &dev->state);
         else {
                 dev->flags |= IFF_UP;
-                net_dmaengine_get();
                 dev_set_rx_mode(dev);
                 dev_activate(dev);
                 add_device_randomness(dev->dev_addr, dev->addr_len);
@@ -1342,7 +1341,6 @@ static int __dev_close_many(struct list_head *head)
                         ops->ndo_stop(dev);
 
                 dev->flags &= ~IFF_UP;
-                net_dmaengine_put();
         }
 
         return 0;
@@ -4405,14 +4403,6 @@ static void net_rx_action(struct softirq_action *h)
 out:
         net_rps_action_and_irq_enable(sd);
 
-#ifdef CONFIG_NET_DMA
-        /*
-         * There may not be any more sk_buffs coming right now, so push
-         * any pending DMA copies to hardware
-         */
-        dma_issue_pending_all();
-#endif
-
         return;
 
 softnet_break:
diff --git a/net/core/sock.c b/net/core/sock.c
index c0fc6bdad1e3..2f143c3b190a 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1452,9 +1452,6 @@ struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
                 atomic_set(&newsk->sk_omem_alloc, 0);
                 skb_queue_head_init(&newsk->sk_receive_queue);
                 skb_queue_head_init(&newsk->sk_write_queue);
-#ifdef CONFIG_NET_DMA
-                skb_queue_head_init(&newsk->sk_async_wait_queue);
-#endif
 
                 spin_lock_init(&newsk->sk_dst_lock);
                 rwlock_init(&newsk->sk_callback_lock);
@@ -2265,9 +2262,6 @@ void sock_init_data(struct socket *sock, struct sock *sk)
         skb_queue_head_init(&sk->sk_receive_queue);
         skb_queue_head_init(&sk->sk_write_queue);
         skb_queue_head_init(&sk->sk_error_queue);
-#ifdef CONFIG_NET_DMA
-        skb_queue_head_init(&sk->sk_async_wait_queue);
-#endif
 
         sk->sk_send_head        =       NULL;
 
diff --git a/net/core/user_dma.c b/net/core/user_dma.c
deleted file mode 100644
index 1b5fefdb8198..000000000000
--- a/net/core/user_dma.c
+++ /dev/null
@@ -1,131 +0,0 @@
-/*
- * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved.
- * Portions based on net/core/datagram.c and copyrighted by their authors.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 of the License, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59
- * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
- *
- * The full GNU General Public License is included in this distribution in the
- * file called COPYING.
- */
-
-/*
- * This code allows the net stack to make use of a DMA engine for
- * skb to iovec copies.
- */
-
-#include <linux/dmaengine.h>
-#include <linux/socket.h>
-#include <linux/export.h>
-#include <net/tcp.h>
-#include <net/netdma.h>
-
-#define NET_DMA_DEFAULT_COPYBREAK 4096
-
-int sysctl_tcp_dma_copybreak = NET_DMA_DEFAULT_COPYBREAK;
-EXPORT_SYMBOL(sysctl_tcp_dma_copybreak);
-
-/**
- *      dma_skb_copy_datagram_iovec - Copy a datagram to an iovec.
- *      @skb - buffer to copy
- *      @offset - offset in the buffer to start copying from
- *      @iovec - io vector to copy to
- *      @len - amount of data to copy from buffer to iovec
- *      @pinned_list - locked iovec buffer data
- *
- *      Note: the iovec is modified during the copy.
- */
-int dma_skb_copy_datagram_iovec(struct dma_chan *chan,
-                        struct sk_buff *skb, int offset, struct iovec *to,
-                        size_t len, struct dma_pinned_list *pinned_list)
-{
-        int start = skb_headlen(skb);
-        int i, copy = start - offset;
-        struct sk_buff *frag_iter;
-        dma_cookie_t cookie = 0;
-
-        /* Copy header. */
-        if (copy > 0) {
-                if (copy > len)
-                        copy = len;
-                cookie = dma_memcpy_to_iovec(chan, to, pinned_list,
-                                            skb->data + offset, copy);
-                if (cookie < 0)
-                        goto fault;
-                len -= copy;
-                if (len == 0)
-                        goto end;
-                offset += copy;
-        }
-
-        /* Copy paged appendix. Hmm... why does this look so complicated? */
-        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-                int end;
-                const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-
-                WARN_ON(start > offset + len);
-
-                end = start + skb_frag_size(frag);
-                copy = end - offset;
-                if (copy > 0) {
-                        struct page *page = skb_frag_page(frag);
-
-                        if (copy > len)
-                                copy = len;
-
-                        cookie = dma_memcpy_pg_to_iovec(chan, to, pinned_list, page,
-                                        frag->page_offset + offset - start, copy);
-                        if (cookie < 0)
-                                goto fault;
-                        len -= copy;
-                        if (len == 0)
-                                goto end;
-                        offset += copy;
-                }
-                start = end;
-        }
-
-        skb_walk_frags(skb, frag_iter) {
-                int end;
-
-                WARN_ON(start > offset + len);
-
-                end = start + frag_iter->len;
-                copy = end - offset;
-                if (copy > 0) {
-                        if (copy > len)
-                                copy = len;
-                        cookie = dma_skb_copy_datagram_iovec(chan, frag_iter,
-                                                             offset - start,
-                                                             to, copy,
-                                                             pinned_list);
-                        if (cookie < 0)
-                                goto fault;
-                        len -= copy;
-                        if (len == 0)
-                                goto end;
-                        offset += copy;
-                }
-                start = end;
-        }
-
-end:
-        if (!len) {
-                skb->dma_cookie = cookie;
-                return cookie;
-        }
-
-fault:
-        return -EFAULT;
-}
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index eb892b4f4814..f9076f295b13 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -848,7 +848,7 @@ int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                 default:
                         dccp_pr_debug("packet_type=%s\n",
                                       dccp_packet_name(dh->dccph_type));
-                        sk_eat_skb(sk, skb, false);
+                        sk_eat_skb(sk, skb);
                 }
 verify_sock_status:
                 if (sock_flag(sk, SOCK_DONE)) {
@@ -905,7 +905,7 @@ verify_sock_status:
                         len = skb->len;
         found_fin_ok:
                 if (!(flags & MSG_PEEK))
-                        sk_eat_skb(sk, skb, false);
+                        sk_eat_skb(sk, skb);
                 break;
         } while (1);
 out:
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 44eba052b43d..c3d2a48481f1 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -635,15 +635,6 @@ static struct ctl_table ipv4_table[] = {
                 .mode           = 0644,
                 .proc_handler   = proc_dointvec
         },
-#ifdef CONFIG_NET_DMA
-        {
-                .procname       = "tcp_dma_copybreak",
-                .data           = &sysctl_tcp_dma_copybreak,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = proc_dointvec
-        },
-#endif
         {
                 .procname       = "tcp_slow_start_after_idle",
                 .data           = &sysctl_tcp_slow_start_after_idle,
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 97c8f5620c43..28595a364f09 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -274,7 +274,6 @@
 #include <net/tcp.h>
 #include <net/xfrm.h>
 #include <net/ip.h>
-#include <net/netdma.h>
 #include <net/sock.h>
 
 #include <asm/uaccess.h>
@@ -1454,39 +1453,6 @@ static void tcp_prequeue_process(struct sock *sk)
         tp->ucopy.memory = 0;
 }
 
-#ifdef CONFIG_NET_DMA
-static void tcp_service_net_dma(struct sock *sk, bool wait)
-{
-        dma_cookie_t done, used;
-        dma_cookie_t last_issued;
-        struct tcp_sock *tp = tcp_sk(sk);
-
-        if (!tp->ucopy.dma_chan)
-                return;
-
-        last_issued = tp->ucopy.dma_cookie;
-        dma_async_issue_pending(tp->ucopy.dma_chan);
-
-        do {
-                if (dma_async_is_tx_complete(tp->ucopy.dma_chan,
-                                              last_issued, &done,
-                                              &used) == DMA_COMPLETE) {
-                        /* Safe to free early-copied skbs now */
-                        __skb_queue_purge(&sk->sk_async_wait_queue);
-                        break;
-                } else {
-                        struct sk_buff *skb;
-                        while ((skb = skb_peek(&sk->sk_async_wait_queue)) &&
-                               (dma_async_is_complete(skb->dma_cookie, done,
-                                                      used) == DMA_COMPLETE)) {
-                                __skb_dequeue(&sk->sk_async_wait_queue);
-                                kfree_skb(skb);
-                        }
-                }
-        } while (wait);
-}
-#endif
-
 static struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off)
 {
         struct sk_buff *skb;
@@ -1504,7 +1470,7 @@ static struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off)
                  * splitted a fat GRO packet, while we released socket lock
                  * in skb_splice_bits()
                  */
-                sk_eat_skb(sk, skb, false);
+                sk_eat_skb(sk, skb);
         }
         return NULL;
 }
@@ -1570,11 +1536,11 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
                                 continue;
                 }
                 if (tcp_hdr(skb)->fin) {
-                        sk_eat_skb(sk, skb, false);
+                        sk_eat_skb(sk, skb);
                         ++seq;
                         break;
                 }
-                sk_eat_skb(sk, skb, false);
+                sk_eat_skb(sk, skb);
                 if (!desc->count)
                         break;
                 tp->copied_seq = seq;
@@ -1612,7 +1578,6 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
         int target;             /* Read at least this many bytes */
         long timeo;
         struct task_struct *user_recv = NULL;
-        bool copied_early = false;
         struct sk_buff *skb;
         u32 urg_hole = 0;
 
@@ -1655,28 +1620,6 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
 
-#ifdef CONFIG_NET_DMA
-        tp->ucopy.dma_chan = NULL;
-        preempt_disable();
-        skb = skb_peek_tail(&sk->sk_receive_queue);
-        {
-                int available = 0;
-
-                if (skb)
-                        available = TCP_SKB_CB(skb)->seq + skb->len - (*seq);
-                if ((available < target) &&
-                    (len > sysctl_tcp_dma_copybreak) && !(flags & MSG_PEEK) &&
-                    !sysctl_tcp_low_latency &&
-                    net_dma_find_channel()) {
-                        preempt_enable();
-                        tp->ucopy.pinned_list =
-                                        dma_pin_iovec_pages(msg->msg_iov, len);
-                } else {
-                        preempt_enable();
-                }
-        }
-#endif
-
         do {
                 u32 offset;
 
@@ -1807,16 +1750,6 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                         /* __ Set realtime policy in scheduler __ */
                 }
 
-#ifdef CONFIG_NET_DMA
-                if (tp->ucopy.dma_chan) {
-                        if (tp->rcv_wnd == 0 &&
-                            !skb_queue_empty(&sk->sk_async_wait_queue)) {
-                                tcp_service_net_dma(sk, true);
-                                tcp_cleanup_rbuf(sk, copied);
-                        } else
-                                dma_async_issue_pending(tp->ucopy.dma_chan);
-                }
-#endif
                 if (copied >= target) {
                         /* Do not sleep, just process backlog. */
                         release_sock(sk);
@@ -1824,11 +1757,6 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                 } else
                         sk_wait_data(sk, &timeo);
 
-#ifdef CONFIG_NET_DMA
-                tcp_service_net_dma(sk, false);  /* Don't block */
-                tp->ucopy.wakeup = 0;
-#endif
-
                 if (user_recv) {
                         int chunk;
 
@@ -1886,43 +1814,13 @@ do_prequeue:
                 }
 
                 if (!(flags & MSG_TRUNC)) {
-#ifdef CONFIG_NET_DMA
-                        if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
-                                tp->ucopy.dma_chan = net_dma_find_channel();
-
-                        if (tp->ucopy.dma_chan) {
-                                tp->ucopy.dma_cookie = dma_skb_copy_datagram_iovec(
-                                        tp->ucopy.dma_chan, skb, offset,
-                                        msg->msg_iov, used,
-                                        tp->ucopy.pinned_list);
-
-                                if (tp->ucopy.dma_cookie < 0) {
-
-                                        pr_alert("%s: dma_cookie < 0\n",
-                                                 __func__);
-
-                                        /* Exception. Bailout! */
-                                        if (!copied)
-                                                copied = -EFAULT;
-                                        break;
-                                }
-
-                                dma_async_issue_pending(tp->ucopy.dma_chan);
-
-                                if ((offset + used) == skb->len)
-                                        copied_early = true;
-
-                        } else
-#endif
-                        {
-                                err = skb_copy_datagram_iovec(skb, offset,
-                                                msg->msg_iov, used);
-                                if (err) {
-                                        /* Exception. Bailout! */
-                                        if (!copied)
-                                                copied = -EFAULT;
-                                        break;
-                                }
+                        err = skb_copy_datagram_iovec(skb, offset,
+                                                      msg->msg_iov, used);
+                        if (err) {
+                                /* Exception. Bailout! */
+                                if (!copied)
+                                        copied = -EFAULT;
+                                break;
                         }
                 }
 
@@ -1942,19 +1840,15 @@ skip_copy:
 
                 if (tcp_hdr(skb)->fin)
                         goto found_fin_ok;
-                if (!(flags & MSG_PEEK)) {
-                        sk_eat_skb(sk, skb, copied_early);
-                        copied_early = false;
-                }
+                if (!(flags & MSG_PEEK))
+                        sk_eat_skb(sk, skb);
                 continue;
 
         found_fin_ok:
                 /* Process the FIN. */
                 ++*seq;
-                if (!(flags & MSG_PEEK)) {
-                        sk_eat_skb(sk, skb, copied_early);
-                        copied_early = false;
-                }
+                if (!(flags & MSG_PEEK))
+                        sk_eat_skb(sk, skb);
                 break;
         } while (len > 0);
 
@@ -1977,16 +1871,6 @@ skip_copy:
                 tp->ucopy.len = 0;
         }
 
-#ifdef CONFIG_NET_DMA
-        tcp_service_net_dma(sk, true);  /* Wait for queue to drain */
-        tp->ucopy.dma_chan = NULL;
-
-        if (tp->ucopy.pinned_list) {
-                dma_unpin_iovec_pages(tp->ucopy.pinned_list);
-                tp->ucopy.pinned_list = NULL;
-        }
-#endif
-
         /* According to UNIX98, msg_name/msg_namelen are ignored
          * on connected socket. I was just happy when found this 8) --ANK
          */
@@ -2330,9 +2214,6 @@ int tcp_disconnect(struct sock *sk, int flags)
         __skb_queue_purge(&sk->sk_receive_queue);
         tcp_write_queue_purge(sk);
         __skb_queue_purge(&tp->out_of_order_queue);
-#ifdef CONFIG_NET_DMA
-        __skb_queue_purge(&sk->sk_async_wait_queue);
-#endif
 
         inet->inet_dport = 0;
 
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index eeaac399420d..1342e9851f97 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -73,7 +73,6 @@
 #include <net/inet_common.h>
 #include <linux/ipsec.h>
 #include <asm/unaligned.h>
-#include <net/netdma.h>
 
 int sysctl_tcp_timestamps __read_mostly = 1;
 int sysctl_tcp_window_scaling __read_mostly = 1;
@@ -4970,53 +4969,6 @@ static inline bool tcp_checksum_complete_user(struct sock *sk,
                __tcp_checksum_complete_user(sk, skb);
 }
 
-#ifdef CONFIG_NET_DMA
-static bool tcp_dma_try_early_copy(struct sock *sk, struct sk_buff *skb,
-                                  int hlen)
-{
-        struct tcp_sock *tp = tcp_sk(sk);
-        int chunk = skb->len - hlen;
-        int dma_cookie;
-        bool copied_early = false;
-
-        if (tp->ucopy.wakeup)
-                return false;
-
-        if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
-                tp->ucopy.dma_chan = net_dma_find_channel();
-
-        if (tp->ucopy.dma_chan && skb_csum_unnecessary(skb)) {
-
-                dma_cookie = dma_skb_copy_datagram_iovec(tp->ucopy.dma_chan,
-                                                         skb, hlen,
-                                                         tp->ucopy.iov, chunk,
-                                                         tp->ucopy.pinned_list);
-
-                if (dma_cookie < 0)
-                        goto out;
-
-                tp->ucopy.dma_cookie = dma_cookie;
-                copied_early = true;
-
-                tp->ucopy.len -= chunk;
-                tp->copied_seq += chunk;
-                tcp_rcv_space_adjust(sk);
-
-                if ((tp->ucopy.len == 0) ||
-                    (tcp_flag_word(tcp_hdr(skb)) & TCP_FLAG_PSH) ||
-                    (atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1))) {
-                        tp->ucopy.wakeup = 1;
-                        sk->sk_data_ready(sk, 0);
-                }
-        } else if (chunk > 0) {
-                tp->ucopy.wakeup = 1;
-                sk->sk_data_ready(sk, 0);
-        }
-out:
-        return copied_early;
-}
-#endif /* CONFIG_NET_DMA */
-
 /* Does PAWS and seqno based validation of an incoming segment, flags will
  * play significant role here.
  */
@@ -5201,14 +5153,6 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
 
                         if (tp->copied_seq == tp->rcv_nxt &&
                             len - tcp_header_len <= tp->ucopy.len) {
-#ifdef CONFIG_NET_DMA
-                                if (tp->ucopy.task == current &&
-                                    sock_owned_by_user(sk) &&
-                                    tcp_dma_try_early_copy(sk, skb, tcp_header_len)) {
-                                        copied_early = 1;
-                                        eaten = 1;
-                                }
-#endif
                                 if (tp->ucopy.task == current &&
                                     sock_owned_by_user(sk) && !copied_early) {
                                         __set_current_state(TASK_RUNNING);
@@ -5274,11 +5218,6 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
                         if (!copied_early || tp->rcv_nxt != tp->rcv_wup)
                                 __tcp_ack_snd_check(sk, 0);
 no_ack:
-#ifdef CONFIG_NET_DMA
-                        if (copied_early)
-                                __skb_queue_tail(&sk->sk_async_wait_queue, skb);
-                        else
-#endif
                         if (eaten)
                                 kfree_skb_partial(skb, fragstolen);
                         sk->sk_data_ready(sk, 0);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 3cf976510497..737c2e270ee3 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -72,7 +72,6 @@
 #include <net/inet_common.h>
 #include <net/timewait_sock.h>
 #include <net/xfrm.h>
-#include <net/netdma.h>
 #include <net/secure_seq.h>
 #include <net/tcp_memcontrol.h>
 #include <net/busy_poll.h>
@@ -1999,18 +1998,8 @@ process:
         bh_lock_sock_nested(sk);
         ret = 0;
         if (!sock_owned_by_user(sk)) {
-#ifdef CONFIG_NET_DMA
-                struct tcp_sock *tp = tcp_sk(sk);
-                if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
-                        tp->ucopy.dma_chan = net_dma_find_channel();
-                if (tp->ucopy.dma_chan)
+                if (!tcp_prequeue(sk, skb))
                         ret = tcp_v4_do_rcv(sk, skb);
-                else
-#endif
-                {
-                        if (!tcp_prequeue(sk, skb))
-                                ret = tcp_v4_do_rcv(sk, skb);
-                }
         } else if (unlikely(sk_add_backlog(sk, skb,
                                            sk->sk_rcvbuf + sk->sk_sndbuf))) {
                 bh_unlock_sock(sk);
@@ -2169,11 +2158,6 @@ void tcp_v4_destroy_sock(struct sock *sk)
         }
 #endif
 
-#ifdef CONFIG_NET_DMA
-        /* Cleans up our sk_async_wait_queue */
-        __skb_queue_purge(&sk->sk_async_wait_queue);
-#endif
-
         /* Clean prequeue, it must be empty really */
         __skb_queue_purge(&tp->ucopy.prequeue);
 
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 889079b2ea85..cb21fccf2089 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -59,7 +59,6 @@
 #include <net/snmp.h>
 #include <net/dsfield.h>
 #include <net/timewait_sock.h>
-#include <net/netdma.h>
 #include <net/inet_common.h>
 #include <net/secure_seq.h>
 #include <net/tcp_memcontrol.h>
@@ -1520,18 +1519,8 @@ process:
         bh_lock_sock_nested(sk);
         ret = 0;
         if (!sock_owned_by_user(sk)) {
-#ifdef CONFIG_NET_DMA
-                struct tcp_sock *tp = tcp_sk(sk);
-                if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
-                        tp->ucopy.dma_chan = net_dma_find_channel();
-                if (tp->ucopy.dma_chan)
+                if (!tcp_prequeue(sk, skb))
                         ret = tcp_v6_do_rcv(sk, skb);
-                else
-#endif
-                {
-                        if (!tcp_prequeue(sk, skb))
-                                ret = tcp_v6_do_rcv(sk, skb);
-                }
         } else if (unlikely(sk_add_backlog(sk, skb,
                                            sk->sk_rcvbuf + sk->sk_sndbuf))) {
                 bh_unlock_sock(sk);
diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c
index 0080d2b0a8ae..bb9cbc17d926 100644
--- a/net/llc/af_llc.c
+++ b/net/llc/af_llc.c
@@ -839,7 +839,7 @@ static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock,
 
                 if (!(flags & MSG_PEEK)) {
                         spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags);
-                        sk_eat_skb(sk, skb, false);
+                        sk_eat_skb(sk, skb);
                         spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags);
                         *seq = 0;
                 }
@@ -861,10 +861,10 @@ copy_uaddr:
                 llc_cmsg_rcv(msg, skb);
 
         if (!(flags & MSG_PEEK)) {
-                        spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags);
-                        sk_eat_skb(sk, skb, false);
-                        spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags);
-                        *seq = 0;
+                spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags);
+                sk_eat_skb(sk, skb);
+                spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags);
+                *seq = 0;
         }
 
         goto out;