Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (22 commits)
  ioat: fix self test for multi-channel case
  dmaengine: bump initcall level to arch_initcall
  dmaengine: advertise all channels on a device to dma_filter_fn
  dmaengine: use idr for registering dma device numbers
  dmaengine: add a release for dma class devices and dependent infrastructure
  ioat: do not perform removal actions at shutdown
  iop-adma: enable module removal
  iop-adma: kill debug BUG_ON
  iop-adma: let devm do its job, don't duplicate free
  dmaengine: kill enum dma_state_client
  dmaengine: remove 'bigref' infrastructure
  dmaengine: kill struct dma_client and supporting infrastructure
  dmaengine: replace dma_async_client_register with dmaengine_get
  atmel-mci: convert to dma_request_channel and down-level dma_slave
  dmatest: convert to dma_request_channel
  dmaengine: introduce dma_request_channel and private channels
  net_dma: convert to dma_find_channel
  dmaengine: provide a common 'issue_pending_all' implementation
  dmaengine: centralize channel allocation, introduce dma_find_channel
  dmaengine: up-level reference counting to the module level
  ...

5 files changed, 9 insertions, 151 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index bab8bcedd62e..5f736f1ceeae 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -170,25 +170,6 @@ static DEFINE_SPINLOCK(ptype_lock);
 static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
 static struct list_head ptype_all __read_mostly;        /* Taps */
 
-#ifdef CONFIG_NET_DMA
-struct net_dma {
-        struct dma_client client;
-        spinlock_t lock;
-        cpumask_t channel_mask;
-        struct dma_chan **channels;
-};
-
-static enum dma_state_client
-netdev_dma_event(struct dma_client *client, struct dma_chan *chan,
-        enum dma_state state);
-
-static struct net_dma net_dma = {
-        .client = {
-                .event_callback = netdev_dma_event,
-        },
-};
-#endif
-
 /*
  * The @dev_base_head list is protected by @dev_base_lock and the rtnl
  * semaphore.
@@ -2754,14 +2735,7 @@ out:
          * There may not be any more sk_buffs coming right now, so push
          * any pending DMA copies to hardware
          */
-        if (!cpus_empty(net_dma.channel_mask)) {
-                int chan_idx;
-                for_each_cpu_mask_nr(chan_idx, net_dma.channel_mask) {
-                        struct dma_chan *chan = net_dma.channels[chan_idx];
-                        if (chan)
-                                dma_async_memcpy_issue_pending(chan);
-                }
-        }
+        dma_issue_pending_all();
 #endif
 
         return;
@@ -4952,122 +4926,6 @@ static int dev_cpu_callback(struct notifier_block *nfb,
         return NOTIFY_OK;
 }
 
-#ifdef CONFIG_NET_DMA
-/**
- * net_dma_rebalance - try to maintain one DMA channel per CPU
- * @net_dma: DMA client and associated data (lock, channels, channel_mask)
- *
- * This is called when the number of channels allocated to the net_dma client
- * changes.  The net_dma client tries to have one DMA channel per CPU.
- */
-
-static void net_dma_rebalance(struct net_dma *net_dma)
-{
-        unsigned int cpu, i, n, chan_idx;
-        struct dma_chan *chan;
-
-        if (cpus_empty(net_dma->channel_mask)) {
-                for_each_online_cpu(cpu)
-                        rcu_assign_pointer(per_cpu(softnet_data, cpu).net_dma, NULL);
-                return;
-        }
-
-        i = 0;
-        cpu = first_cpu(cpu_online_map);
-
-        for_each_cpu_mask_nr(chan_idx, net_dma->channel_mask) {
-                chan = net_dma->channels[chan_idx];
-
-                n = ((num_online_cpus() / cpus_weight(net_dma->channel_mask))
-                   + (i < (num_online_cpus() %
-                        cpus_weight(net_dma->channel_mask)) ? 1 : 0));
-
-                while(n) {
-                        per_cpu(softnet_data, cpu).net_dma = chan;
-                        cpu = next_cpu(cpu, cpu_online_map);
-                        n--;
-                }
-                i++;
-        }
-}
-
-/**
- * netdev_dma_event - event callback for the net_dma_client
- * @client: should always be net_dma_client
- * @chan: DMA channel for the event
- * @state: DMA state to be handled
- */
-static enum dma_state_client
-netdev_dma_event(struct dma_client *client, struct dma_chan *chan,
-        enum dma_state state)
-{
-        int i, found = 0, pos = -1;
-        struct net_dma *net_dma =
-                container_of(client, struct net_dma, client);
-        enum dma_state_client ack = DMA_DUP; /* default: take no action */
-
-        spin_lock(&net_dma->lock);
-        switch (state) {
-        case DMA_RESOURCE_AVAILABLE:
-                for (i = 0; i < nr_cpu_ids; i++)
-                        if (net_dma->channels[i] == chan) {
-                                found = 1;
-                                break;
-                        } else if (net_dma->channels[i] == NULL && pos < 0)
-                                pos = i;
-
-                if (!found && pos >= 0) {
-                        ack = DMA_ACK;
-                        net_dma->channels[pos] = chan;
-                        cpu_set(pos, net_dma->channel_mask);
-                        net_dma_rebalance(net_dma);
-                }
-                break;
-        case DMA_RESOURCE_REMOVED:
-                for (i = 0; i < nr_cpu_ids; i++)
-                        if (net_dma->channels[i] == chan) {
-                                found = 1;
-                                pos = i;
-                                break;
-                        }
-
-                if (found) {
-                        ack = DMA_ACK;
-                        cpu_clear(pos, net_dma->channel_mask);
-                        net_dma->channels[i] = NULL;
-                        net_dma_rebalance(net_dma);
-                }
-                break;
-        default:
-                break;
-        }
-        spin_unlock(&net_dma->lock);
-
-        return ack;
-}
-
-/**
- * netdev_dma_register - register the networking subsystem as a DMA client
- */
-static int __init netdev_dma_register(void)
-{
-        net_dma.channels = kzalloc(nr_cpu_ids * sizeof(struct net_dma),
-                                                                GFP_KERNEL);
-        if (unlikely(!net_dma.channels)) {
-                printk(KERN_NOTICE
-                                "netdev_dma: no memory for net_dma.channels\n");
-                return -ENOMEM;
-        }
-        spin_lock_init(&net_dma.lock);
-        dma_cap_set(DMA_MEMCPY, net_dma.client.cap_mask);
-        dma_async_client_register(&net_dma.client);
-        dma_async_client_chan_request(&net_dma.client);
-        return 0;
-}
-
-#else
-static int __init netdev_dma_register(void) { return -ENODEV; }
-#endif /* CONFIG_NET_DMA */
 
 /**
  *      netdev_increment_features - increment feature set by one
@@ -5287,14 +5145,15 @@ static int __init net_dev_init(void)
         if (register_pernet_device(&default_device_ops))
                 goto out;
 
-        netdev_dma_register();
-
         open_softirq(NET_TX_SOFTIRQ, net_tx_action);
         open_softirq(NET_RX_SOFTIRQ, net_rx_action);
 
         hotcpu_notifier(dev_cpu_callback, 0);
         dst_init();
         dev_mcast_init();
+        #ifdef CONFIG_NET_DMA
+        dmaengine_get();
+        #endif
         rc = 0;
 out:
         return rc;
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index bd6ff907d9e4..ce572f9dff02 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1313,7 +1313,7 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                 if ((available < target) &&
                     (len > sysctl_tcp_dma_copybreak) && !(flags & MSG_PEEK) &&
                     !sysctl_tcp_low_latency &&
-                    __get_cpu_var(softnet_data).net_dma) {
+                    dma_find_channel(DMA_MEMCPY)) {
                         preempt_enable_no_resched();
                         tp->ucopy.pinned_list =
                                         dma_pin_iovec_pages(msg->msg_iov, len);
@@ -1523,7 +1523,7 @@ do_prequeue:
                 if (!(flags & MSG_TRUNC)) {
 #ifdef CONFIG_NET_DMA
                         if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
-                                tp->ucopy.dma_chan = get_softnet_dma();
+                                tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
 
                         if (tp->ucopy.dma_chan) {
                                 tp->ucopy.dma_cookie = dma_skb_copy_datagram_iovec(
@@ -1628,7 +1628,6 @@ skip_copy:
 
                 /* Safe to free early-copied skbs now */
                 __skb_queue_purge(&sk->sk_async_wait_queue);
-                dma_chan_put(tp->ucopy.dma_chan);
                 tp->ucopy.dma_chan = NULL;
         }
         if (tp->ucopy.pinned_list) {
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 99b7ecbe8893..a6961d75c7ea 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5005,7 +5005,7 @@ static int tcp_dma_try_early_copy(struct sock *sk, struct sk_buff *skb,
                 return 0;
 
         if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
-                tp->ucopy.dma_chan = get_softnet_dma();
+                tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
 
         if (tp->ucopy.dma_chan && skb_csum_unnecessary(skb)) {
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 9d839fa9331e..19d7b429a262 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1594,7 +1594,7 @@ process:
 #ifdef CONFIG_NET_DMA
                 struct tcp_sock *tp = tcp_sk(sk);
                 if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
-                        tp->ucopy.dma_chan = get_softnet_dma();
+                        tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
                 if (tp->ucopy.dma_chan)
                         ret = tcp_v4_do_rcv(sk, skb);
                 else
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 1297306d729c..e5b85d45bee8 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1675,7 +1675,7 @@ process:
 #ifdef CONFIG_NET_DMA
                 struct tcp_sock *tp = tcp_sk(sk);
                 if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
-                        tp->ucopy.dma_chan = get_softnet_dma();
+                        tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
                 if (tp->ucopy.dma_chan)
                         ret = tcp_v6_do_rcv(sk, skb);
                 else