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* Re: [PATCH net-next v4 0/7] switchdev offload flags
From: David Miller @ 2015-02-02  7:16 UTC (permalink / raw)
  To: roopa
  Cc: jiri, sfeldma, jhs, bcrl, tgraf, john.fastabend, stephen,
	vyasevic, ronen.arad, netdev, shm, gospo
In-Reply-To: <1422600017-42393-1-git-send-email-roopa@cumulusnetworks.com>

From: roopa@cumulusnetworks.com
Date: Thu, 29 Jan 2015 22:40:10 -0800

> This patch series introduces new offload flags for switchdev.
> Kernel network subsystems can use this flag to accelerate
> network functions by offloading to hw.

Series applied to net-next, thanks.

^ permalink raw reply

* Re: [PATCH] net: rocker: Add support for retrieving port level statistics
From: David Miller @ 2015-02-02  7:17 UTC (permalink / raw)
  To: dsahern; +Cc: netdev, sfeldma
In-Reply-To: <1422590373-22807-1-git-send-email-dsahern@gmail.com>

From: David Ahern <dsahern@gmail.com>
Date: Thu, 29 Jan 2015 20:59:33 -0700

> Add support for retrieving port level statistics from device.
> Hook is added for ethtool's stats functionality. For example,
> 
> $ ethtool -S eth3
> NIC statistics:
>      rx_packets: 12
>      rx_bytes: 2790
>      rx_dropped: 0
>      rx_errors: 0
>      tx_packets: 8
>      tx_bytes: 728
>      tx_dropped: 0
>      tx_errors: 0
> 
> Signed-off-by: David Ahern <dsahern@gmail.com>

Applied to net-next, thanks.

^ permalink raw reply

* Re: [PATCH] tun: orphan an skb on tx
From: David Woodhouse @ 2015-02-02  7:27 UTC (permalink / raw)
  To: David Miller
  Cc: mst, herbert, eric.dumazet, jan.kiszka, netdev, linux-kernel,
	qemu-devel
In-Reply-To: <20150201.210716.588479604128207372.davem@davemloft.net>

[-- Attachment #1: Type: text/plain, Size: 2997 bytes --]

On Sun, 2015-02-01 at 21:07 -0800, David Miller wrote:
> From: David Woodhouse <dwmw2@infradead.org>
> Date: Sun, 01 Feb 2015 21:29:43 +0000
> 
> > I really was looking for some way to push down something like an XFRM
> > state into the tun device and just say "shove them out here until I tell
> > you otherwise".
> 
> People decided to use TUN and push VPN stuff back into userspace,
> and there are repercussions for that decision.
> 
> I'm not saying this to be mean or whatever, but I was very
> disappointed when userland IPSEC solutions using TUN started showing
> up.

Yeah. That's a valid criticism of vpnc, certainly. I never did
understand why it reimplemented the IPSec stack.

For my OpenConnect client it's somewhat more justified though — the
initial data transport there is over TLS, which the kernel doesn't
support. And if we *can* establish UDP communication, that's over DTLS
which the kernel doesn't support either. It's not even the *standard*
version of DTLS because Cisco are still using a pre-RFC4347 version of
the protocol. And we also need to probe the UDP connectivity and do
keepalives and manage the fallback to using the TCP data transport.

It's not like vpnc where it really is just a case of setting up the ESP
context and letting it run.

It's only now I've added Juniper support, which uses ESP-in-UDP for the
data transport, that I'm doing something that the kernel supports at
all. And now I'm looking at how to make use of that.

> We might as well have not have implemented the IPSEC stack at all,
> because as a result of the userland VPN stuff our IPSEC stack is
> largely unused except by a very narrow group of users.

Well, I'd love to make better use of it if I can. I do suspect it makes
most sense for userspace to continue to manage the probing of UDP
connectivity, and the fallback to TCP mode — and I suspect it also makes
sense to continue to use tun for passing packets up to the VPN client
when it's using the TCP transport.

So the question would be how we handle redirecting the packet flow to
the optional UDP transport, when the VPN client determines that it's
available. For the sake of the user setting up firewall and routing
rules, I do think it's important that it continues to appear to
userspace as the *same* device for the entire lifetime of the session,
regardless of which transport the packets happen to be using at a given
moment in time. It doesn't *have* to be tun, though. 

You don't seem to like my suggestion of somehow pushing down an XFRM
state to the tun device to direct the packets out there instead of up to
userspace. Do you have an alternative suggestion... or a specific
concern that would help me come up with something you like better?

I'm guessing you don't want to push the *whole* management of the TLS
control connection *and* the UDP transport, and probing the latter with
keepalives, into the kernel? I certainly don't :)

-- 
dwmw2


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^ permalink raw reply

* [PATCH v2 18/18] vhost: vhost_scsi_handle_vq() should just use copy_from_user()
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev, Michael S. Tsirkin, Nicholas A. Bellinger, kvm
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

it has just verified that it asks no more than the length of the
first segment of iovec.

And with that the last user of stuff in lib/iovec.c is gone.
RIP.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Cc: kvm@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 drivers/vhost/scsi.c |  2 +-
 include/linux/uio.h  |  2 --
 lib/Makefile         |  2 +-
 lib/iovec.c          | 36 ------------------------------------
 4 files changed, 2 insertions(+), 40 deletions(-)
 delete mode 100644 lib/iovec.c

diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index d695b16..dc78d87 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -1079,7 +1079,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 			       req_size, vq->iov[0].iov_len);
 			break;
 		}
-		ret = memcpy_fromiovecend(req, &vq->iov[0], 0, req_size);
+		ret = copy_from_user(req, vq->iov[0].iov_base, req_size);
 		if (unlikely(ret)) {
 			vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 			break;
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 02bd8a9..3e0cb4e 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -135,6 +135,4 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count)
 size_t csum_and_copy_to_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 
-int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov,
-			int offset, int len);
 #endif
diff --git a/lib/Makefile b/lib/Makefile
index 3c3b30b..1071d06 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -24,7 +24,7 @@ obj-y	+= lockref.o
 
 obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
 	 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
-	 gcd.o lcm.o list_sort.o uuid.o flex_array.o iovec.o clz_ctz.o \
+	 gcd.o lcm.o list_sort.o uuid.o flex_array.o clz_ctz.o \
 	 bsearch.o find_last_bit.o find_next_bit.o llist.o memweight.o kfifo.o \
 	 percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o
 obj-y += string_helpers.o
diff --git a/lib/iovec.c b/lib/iovec.c
deleted file mode 100644
index d8f17a9..0000000
--- a/lib/iovec.c
+++ /dev/null
@@ -1,36 +0,0 @@
-#include <linux/uaccess.h>
-#include <linux/export.h>
-#include <linux/uio.h>
-
-/*
- *	Copy iovec to kernel. Returns -EFAULT on error.
- */
-
-int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov,
-			int offset, int len)
-{
-	/* No data? Done! */
-	if (len == 0)
-		return 0;
-
-	/* Skip over the finished iovecs */
-	while (offset >= iov->iov_len) {
-		offset -= iov->iov_len;
-		iov++;
-	}
-
-	while (len > 0) {
-		u8 __user *base = iov->iov_base + offset;
-		int copy = min_t(unsigned int, len, iov->iov_len - offset);
-
-		offset = 0;
-		if (copy_from_user(kdata, base, copy))
-			return -EFAULT;
-		len -= copy;
-		kdata += copy;
-		iov++;
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL(memcpy_fromiovecend);
-- 
2.1.4


^ permalink raw reply related

* [PATCH v2 02/18] ipv4: raw_send_hdrinc(): pass msghdr
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Switch from passing msg->iov_iter.iov to passing msg itself

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 net/ipv4/raw.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 0bb68df..2c9d252 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -337,7 +337,7 @@ int raw_rcv(struct sock *sk, struct sk_buff *skb)
 }
 
 static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
-			   void *from, size_t length,
+			   struct msghdr *msg, size_t length,
 			   struct rtable **rtp,
 			   unsigned int flags)
 {
@@ -382,7 +382,7 @@ static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
 
 	skb->transport_header = skb->network_header;
 	err = -EFAULT;
-	if (memcpy_fromiovecend((void *)iph, from, 0, length))
+	if (memcpy_fromiovecend((void *)iph, msg->msg_iter.iov, 0, length))
 		goto error_free;
 
 	iphlen = iph->ihl * 4;
@@ -625,8 +625,7 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 back_from_confirm:
 
 	if (inet->hdrincl)
-		/* XXX: stripping const */
-		err = raw_send_hdrinc(sk, &fl4, (struct iovec *)msg->msg_iter.iov, len,
+		err = raw_send_hdrinc(sk, &fl4, msg, len,
 				      &rt, msg->msg_flags);
 
 	 else {
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 01/18] netlink: make the check for "send from tx_ring" deterministic
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

As it is, zero msg_iovlen means that the first iovec in the kernel
array of iovecs is left uninitialized, so checking if its ->iov_base
is NULL is random.  Since the real users of that thing are doing
sendto(fd, NULL, 0, ...), they are getting msg_iovlen = 1 and
msg_iov[0] = {NULL, 0}, which is what this test is trying to catch.
As suggested by davem, let's just check that msg_iovlen was 1 and
msg_iov[0].iov_base was NULL - _that_ is well-defined and it catches
what we want to catch.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 net/netlink/af_netlink.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index a36777b..af51d58 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -2298,7 +2298,11 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
 			goto out;
 	}
 
+        /* It's a really convoluted way for userland to ask for mmaped
+	 * sendmsg(), but that's what we've got...  */
 	if (netlink_tx_is_mmaped(sk) &&
+	    msg->msg_iter.type == ITER_IOVEC &&
+	    msg->msg_iter.nr_segs == 1 &&
 	    msg->msg_iter.iov->iov_base == NULL) {
 		err = netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group,
 					   &scm);
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 03/18] ipv6: rawv6_send_hdrinc(): pass msghdr
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Switch from passing msg->iov_iter.iov to passing msg itself

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 net/ipv6/raw.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index ee25631..0dbb328 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -609,7 +609,7 @@ out:
 	return err;
 }
 
-static int rawv6_send_hdrinc(struct sock *sk, void *from, int length,
+static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
 			struct flowi6 *fl6, struct dst_entry **dstp,
 			unsigned int flags)
 {
@@ -648,7 +648,7 @@ static int rawv6_send_hdrinc(struct sock *sk, void *from, int length,
 	skb->ip_summed = CHECKSUM_NONE;
 
 	skb->transport_header = skb->network_header;
-	err = memcpy_fromiovecend((void *)iph, from, 0, length);
+	err = memcpy_fromiovecend((void *)iph, msg->msg_iter.iov, 0, length);
 	if (err)
 		goto error_fault;
 
@@ -886,8 +886,7 @@ static int rawv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 
 back_from_confirm:
 	if (inet->hdrincl)
-		/* XXX: stripping const */
-		err = rawv6_send_hdrinc(sk, (struct iovec *)msg->msg_iter.iov, len, &fl6, &dst, msg->msg_flags);
+		err = rawv6_send_hdrinc(sk, msg, len, &fl6, &dst, msg->msg_flags);
 	else {
 		lock_sock(sk);
 		err = ip6_append_data(sk, raw6_getfrag, &rfv,
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 04/18] vmci: propagate msghdr all way down to __qp_memcpy_to_queue()
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Switch from passing msg->iov_iter.iov to passing msg itself

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 drivers/misc/vmw_vmci/vmci_queue_pair.c | 16 ++++++++--------
 include/linux/vmw_vmci_api.h            |  2 +-
 net/vmw_vsock/vmci_transport.c          |  3 +--
 3 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/drivers/misc/vmw_vmci/vmci_queue_pair.c b/drivers/misc/vmw_vmci/vmci_queue_pair.c
index 7aaaf51..35f19a6 100644
--- a/drivers/misc/vmw_vmci/vmci_queue_pair.c
+++ b/drivers/misc/vmw_vmci/vmci_queue_pair.c
@@ -370,12 +370,12 @@ static int __qp_memcpy_to_queue(struct vmci_queue *queue,
 			to_copy = size - bytes_copied;
 
 		if (is_iovec) {
-			struct iovec *iov = (struct iovec *)src;
+			struct msghdr *msg = (struct msghdr *)src;
 			int err;
 
 			/* The iovec will track bytes_copied internally. */
-			err = memcpy_fromiovec((u8 *)va + page_offset,
-					       iov, to_copy);
+			err = memcpy_from_msg((u8 *)va + page_offset,
+					      msg, to_copy);
 			if (err != 0) {
 				if (kernel_if->host)
 					kunmap(kernel_if->u.h.page[page_index]);
@@ -580,7 +580,7 @@ static int qp_memcpy_from_queue(void *dest,
  */
 static int qp_memcpy_to_queue_iov(struct vmci_queue *queue,
 				  u64 queue_offset,
-				  const void *src,
+				  const void *msg,
 				  size_t src_offset, size_t size)
 {
 
@@ -588,7 +588,7 @@ static int qp_memcpy_to_queue_iov(struct vmci_queue *queue,
 	 * We ignore src_offset because src is really a struct iovec * and will
 	 * maintain offset internally.
 	 */
-	return __qp_memcpy_to_queue(queue, queue_offset, src, size, true);
+	return __qp_memcpy_to_queue(queue, queue_offset, msg, size, true);
 }
 
 /*
@@ -3223,13 +3223,13 @@ EXPORT_SYMBOL_GPL(vmci_qpair_peek);
  * of bytes enqueued or < 0 on error.
  */
 ssize_t vmci_qpair_enquev(struct vmci_qp *qpair,
-			  void *iov,
+			  struct msghdr *msg,
 			  size_t iov_size,
 			  int buf_type)
 {
 	ssize_t result;
 
-	if (!qpair || !iov)
+	if (!qpair)
 		return VMCI_ERROR_INVALID_ARGS;
 
 	qp_lock(qpair);
@@ -3238,7 +3238,7 @@ ssize_t vmci_qpair_enquev(struct vmci_qp *qpair,
 		result = qp_enqueue_locked(qpair->produce_q,
 					   qpair->consume_q,
 					   qpair->produce_q_size,
-					   iov, iov_size,
+					   msg, iov_size,
 					   qp_memcpy_to_queue_iov);
 
 		if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY &&
diff --git a/include/linux/vmw_vmci_api.h b/include/linux/vmw_vmci_api.h
index 5691f75..63df3a2a 100644
--- a/include/linux/vmw_vmci_api.h
+++ b/include/linux/vmw_vmci_api.h
@@ -74,7 +74,7 @@ ssize_t vmci_qpair_dequeue(struct vmci_qp *qpair,
 ssize_t vmci_qpair_peek(struct vmci_qp *qpair, void *buf, size_t buf_size,
 			int mode);
 ssize_t vmci_qpair_enquev(struct vmci_qp *qpair,
-			  void *iov, size_t iov_size, int mode);
+			  struct msghdr *msg, size_t iov_size, int mode);
 ssize_t vmci_qpair_dequev(struct vmci_qp *qpair,
 			  struct msghdr *msg, size_t iov_size, int mode);
 ssize_t vmci_qpair_peekv(struct vmci_qp *qpair, struct msghdr *msg, size_t iov_size,
diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c
index 02d2e52..7f32550 100644
--- a/net/vmw_vsock/vmci_transport.c
+++ b/net/vmw_vsock/vmci_transport.c
@@ -1850,8 +1850,7 @@ static ssize_t vmci_transport_stream_enqueue(
 	struct msghdr *msg,
 	size_t len)
 {
-	/* XXX: stripping const */
-	return vmci_qpair_enquev(vmci_trans(vsk)->qpair, (struct iovec *)msg->msg_iter.iov, len, 0);
+	return vmci_qpair_enquev(vmci_trans(vsk)->qpair, msg, len, 0);
 }
 
 static s64 vmci_transport_stream_has_data(struct vsock_sock *vsk)
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 07/18] ip: stash a pointer to msghdr in struct ping_fakehdr
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

... instead of storing its ->mgs_iter.iov there

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/net/ping.h | 2 +-
 net/ipv4/ping.c    | 7 +++----
 net/ipv6/ping.c    | 3 +--
 3 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/include/net/ping.h b/include/net/ping.h
index f074060..cc16d41 100644
--- a/include/net/ping.h
+++ b/include/net/ping.h
@@ -59,7 +59,7 @@ extern struct pingv6_ops pingv6_ops;
 
 struct pingfakehdr {
 	struct icmphdr icmph;
-	struct iovec *iov;
+	struct msghdr *msg;
 	sa_family_t family;
 	__wsum wcheck;
 };
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 2a3720f..9e15ba7 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -602,14 +602,14 @@ int ping_getfrag(void *from, char *to,
 		if (fraglen < sizeof(struct icmphdr))
 			BUG();
 		if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
-			    pfh->iov, 0, fraglen - sizeof(struct icmphdr),
+			    pfh->msg->msg_iter.iov, 0, fraglen - sizeof(struct icmphdr),
 			    &pfh->wcheck))
 			return -EFAULT;
 	} else if (offset < sizeof(struct icmphdr)) {
 			BUG();
 	} else {
 		if (csum_partial_copy_fromiovecend
-				(to, pfh->iov, offset - sizeof(struct icmphdr),
+				(to, pfh->msg->msg_iter.iov, offset - sizeof(struct icmphdr),
 				 fraglen, &pfh->wcheck))
 			return -EFAULT;
 	}
@@ -811,8 +811,7 @@ back_from_confirm:
 	pfh.icmph.checksum = 0;
 	pfh.icmph.un.echo.id = inet->inet_sport;
 	pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
-	/* XXX: stripping const */
-	pfh.iov = (struct iovec *)msg->msg_iter.iov;
+	pfh.msg = msg;
 	pfh.wcheck = 0;
 	pfh.family = AF_INET;
 
diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index 2d31483..bd46f73 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -163,8 +163,7 @@ int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 	pfh.icmph.checksum = 0;
 	pfh.icmph.un.echo.id = inet->inet_sport;
 	pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
-	/* XXX: stripping const */
-	pfh.iov = (struct iovec *)msg->msg_iter.iov;
+	pfh.msg = msg;
 	pfh.wcheck = 0;
 	pfh.family = AF_INET6;
 
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 05/18] rxrpc: switch rxrpc_send_data() to iov_iter primitives
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Convert skb_add_data() to iov_iter; allows to get rid of the explicit
messing with iovec in its only caller - skb_add_data() will keep advancing
->msg_iter for us, so there's no need to similate that manually.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/linux/skbuff.h | 11 +++++------
 net/rxrpc/ar-output.c  | 43 ++++++++++---------------------------------
 2 files changed, 15 insertions(+), 39 deletions(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 85ab7d7..9a8bafe 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2484,19 +2484,18 @@ static inline int skb_put_padto(struct sk_buff *skb, unsigned int len)
 }
 
 static inline int skb_add_data(struct sk_buff *skb,
-			       char __user *from, int copy)
+			       struct iov_iter *from, int copy)
 {
 	const int off = skb->len;
 
 	if (skb->ip_summed == CHECKSUM_NONE) {
-		int err = 0;
-		__wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy),
-							    copy, 0, &err);
-		if (!err) {
+		__wsum csum = 0;
+		if (csum_and_copy_from_iter(skb_put(skb, copy), copy,
+					    &csum, from) == copy) {
 			skb->csum = csum_block_add(skb->csum, csum, off);
 			return 0;
 		}
-	} else if (!copy_from_user(skb_put(skb, copy), from, copy))
+	} else if (copy_from_iter(skb_put(skb, copy), copy, from) == copy)
 		return 0;
 
 	__skb_trim(skb, off);
diff --git a/net/rxrpc/ar-output.c b/net/rxrpc/ar-output.c
index e1a9373..963a5b9 100644
--- a/net/rxrpc/ar-output.c
+++ b/net/rxrpc/ar-output.c
@@ -529,13 +529,11 @@ static int rxrpc_send_data(struct kiocb *iocb,
 			   struct msghdr *msg, size_t len)
 {
 	struct rxrpc_skb_priv *sp;
-	unsigned char __user *from;
 	struct sk_buff *skb;
-	const struct iovec *iov;
 	struct sock *sk = &rx->sk;
 	long timeo;
 	bool more;
-	int ret, ioc, segment, copied;
+	int ret, copied;
 
 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
 
@@ -545,25 +543,17 @@ static int rxrpc_send_data(struct kiocb *iocb,
 	if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
 		return -EPIPE;
 
-	iov = msg->msg_iter.iov;
-	ioc = msg->msg_iter.nr_segs - 1;
-	from = iov->iov_base;
-	segment = iov->iov_len;
-	iov++;
 	more = msg->msg_flags & MSG_MORE;
 
 	skb = call->tx_pending;
 	call->tx_pending = NULL;
 
 	copied = 0;
-	do {
+	if (len > iov_iter_count(&msg->msg_iter))
+		len = iov_iter_count(&msg->msg_iter);
+	while (len) {
 		int copy;
 
-		if (segment > len)
-			segment = len;
-
-		_debug("SEGMENT %d @%p", segment, from);
-
 		if (!skb) {
 			size_t size, chunk, max, space;
 
@@ -631,13 +621,13 @@ static int rxrpc_send_data(struct kiocb *iocb,
 		/* append next segment of data to the current buffer */
 		copy = skb_tailroom(skb);
 		ASSERTCMP(copy, >, 0);
-		if (copy > segment)
-			copy = segment;
+		if (copy > len)
+			copy = len;
 		if (copy > sp->remain)
 			copy = sp->remain;
 
 		_debug("add");
-		ret = skb_add_data(skb, from, copy);
+		ret = skb_add_data(skb, &msg->msg_iter, copy);
 		_debug("added");
 		if (ret < 0)
 			goto efault;
@@ -646,18 +636,6 @@ static int rxrpc_send_data(struct kiocb *iocb,
 		copied += copy;
 
 		len -= copy;
-		segment -= copy;
-		from += copy;
-		while (segment == 0 && ioc > 0) {
-			from = iov->iov_base;
-			segment = iov->iov_len;
-			iov++;
-			ioc--;
-		}
-		if (len == 0) {
-			segment = 0;
-			ioc = 0;
-		}
 
 		/* check for the far side aborting the call or a network error
 		 * occurring */
@@ -665,7 +643,7 @@ static int rxrpc_send_data(struct kiocb *iocb,
 			goto call_aborted;
 
 		/* add the packet to the send queue if it's now full */
-		if (sp->remain <= 0 || (segment == 0 && !more)) {
+		if (sp->remain <= 0 || (!len && !more)) {
 			struct rxrpc_connection *conn = call->conn;
 			uint32_t seq;
 			size_t pad;
@@ -711,11 +689,10 @@ static int rxrpc_send_data(struct kiocb *iocb,
 
 			memcpy(skb->head, &sp->hdr,
 			       sizeof(struct rxrpc_header));
-			rxrpc_queue_packet(call, skb, segment == 0 && !more);
+			rxrpc_queue_packet(call, skb, !iov_iter_count(&msg->msg_iter) && !more);
 			skb = NULL;
 		}
-
-	} while (segment > 0);
+	}
 
 success:
 	ret = copied;
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 06/18] rxrpc: make the users of rxrpc_kernel_send_data() set kvec-backed msg_iter properly
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Use iov_iter_kvec() there, get rid of set_fs() games - now that
rxrpc_send_data() uses iov_iter primitives, it'll handle ITER_KVEC just
fine.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/afs/rxrpc.c        | 14 +++++++-------
 net/rxrpc/ar-output.c |  3 ---
 2 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 06e14bf..dbc732e 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -306,8 +306,8 @@ static int afs_send_pages(struct afs_call *call, struct msghdr *msg,
 
 			_debug("- range %u-%u%s",
 			       offset, to, msg->msg_flags ? " [more]" : "");
-			iov_iter_init(&msg->msg_iter, WRITE,
-				      (struct iovec *) iov, 1, to - offset);
+			iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC,
+				      iov, 1, to - offset);
 
 			/* have to change the state *before* sending the last
 			 * packet as RxRPC might give us the reply before it
@@ -384,7 +384,7 @@ int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp,
 
 	msg.msg_name		= NULL;
 	msg.msg_namelen		= 0;
-	iov_iter_init(&msg.msg_iter, WRITE, (struct iovec *)iov, 1,
+	iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 1,
 		      call->request_size);
 	msg.msg_control		= NULL;
 	msg.msg_controllen	= 0;
@@ -770,7 +770,7 @@ static int afs_deliver_cm_op_id(struct afs_call *call, struct sk_buff *skb,
 void afs_send_empty_reply(struct afs_call *call)
 {
 	struct msghdr msg;
-	struct iovec iov[1];
+	struct kvec iov[1];
 
 	_enter("");
 
@@ -778,7 +778,7 @@ void afs_send_empty_reply(struct afs_call *call)
 	iov[0].iov_len		= 0;
 	msg.msg_name		= NULL;
 	msg.msg_namelen		= 0;
-	iov_iter_init(&msg.msg_iter, WRITE, iov, 0, 0);	/* WTF? */
+	iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 0, 0);	/* WTF? */
 	msg.msg_control		= NULL;
 	msg.msg_controllen	= 0;
 	msg.msg_flags		= 0;
@@ -805,7 +805,7 @@ void afs_send_empty_reply(struct afs_call *call)
 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
 {
 	struct msghdr msg;
-	struct iovec iov[1];
+	struct kvec iov[1];
 	int n;
 
 	_enter("");
@@ -814,7 +814,7 @@ void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
 	iov[0].iov_len		= len;
 	msg.msg_name		= NULL;
 	msg.msg_namelen		= 0;
-	iov_iter_init(&msg.msg_iter, WRITE, iov, 1, len);
+	iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 1, len);
 	msg.msg_control		= NULL;
 	msg.msg_controllen	= 0;
 	msg.msg_flags		= 0;
diff --git a/net/rxrpc/ar-output.c b/net/rxrpc/ar-output.c
index 963a5b9..8331c95 100644
--- a/net/rxrpc/ar-output.c
+++ b/net/rxrpc/ar-output.c
@@ -232,10 +232,7 @@ int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg,
 		   call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
 		ret = -EPROTO; /* request phase complete for this client call */
 	} else {
-		mm_segment_t oldfs = get_fs();
-		set_fs(KERNEL_DS);
 		ret = rxrpc_send_data(NULL, call->socket, call, msg, len);
-		set_fs(oldfs);
 	}
 
 	release_sock(&call->socket->sk);
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 10/18] tipc: tipc ->sendmsg() conversion
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev, Jon Maloy
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

This one needs to copy the same data from user potentially more than
once.  Sadly, MTU changes can trigger that ;-/

Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 net/tipc/msg.c    |  7 ++-----
 net/tipc/socket.c | 14 ++++++++++++--
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/net/tipc/msg.c b/net/tipc/msg.c
index 18aba9e..da67c8d 100644
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -189,7 +189,6 @@ err:
  * tipc_msg_build - create buffer chain containing specified header and data
  * @mhdr: Message header, to be prepended to data
  * @m: User message
- * @offset: Posision in iov to start copying from
  * @dsz: Total length of user data
  * @pktmax: Max packet size that can be used
  * @list: Buffer or chain of buffers to be returned to caller
@@ -221,8 +220,7 @@ int tipc_msg_build(struct net *net, struct tipc_msg *mhdr, struct msghdr *m,
 		__skb_queue_tail(list, skb);
 		skb_copy_to_linear_data(skb, mhdr, mhsz);
 		pktpos = skb->data + mhsz;
-		if (!dsz || !memcpy_fromiovecend(pktpos, m->msg_iter.iov, offset,
-						 dsz))
+		if (copy_from_iter(pktpos, dsz, &m->msg_iter) == dsz)
 			return dsz;
 		rc = -EFAULT;
 		goto error;
@@ -252,12 +250,11 @@ int tipc_msg_build(struct net *net, struct tipc_msg *mhdr, struct msghdr *m,
 		if (drem < pktrem)
 			pktrem = drem;
 
-		if (memcpy_fromiovecend(pktpos, m->msg_iter.iov, offset, pktrem)) {
+		if (copy_from_iter(pktpos, pktrem, &m->msg_iter) != pktrem) {
 			rc = -EFAULT;
 			goto error;
 		}
 		drem -= pktrem;
-		offset += pktrem;
 
 		if (!drem)
 			break;
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 679a220..caa4d66 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -733,6 +733,7 @@ static int tipc_sendmcast(struct  socket *sock, struct tipc_name_seq *seq,
 	struct net *net = sock_net(sk);
 	struct tipc_msg *mhdr = &tipc_sk(sk)->phdr;
 	struct sk_buff_head head;
+	struct iov_iter save = msg->msg_iter;
 	uint mtu;
 	int rc;
 
@@ -758,8 +759,10 @@ new_mtu:
 			rc = dsz;
 			break;
 		}
-		if (rc == -EMSGSIZE)
+		if (rc == -EMSGSIZE) {
+			msg->msg_iter = save;
 			goto new_mtu;
+		}
 		if (rc != -ELINKCONG)
 			break;
 		tipc_sk(sk)->link_cong = 1;
@@ -895,6 +898,7 @@ static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock,
 	struct sk_buff_head head;
 	struct sk_buff *skb;
 	struct tipc_name_seq *seq = &dest->addr.nameseq;
+	struct iov_iter save;
 	u32 mtu;
 	long timeo;
 	int rc;
@@ -963,6 +967,7 @@ static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock,
 		msg_set_hdr_sz(mhdr, BASIC_H_SIZE);
 	}
 
+	save = m->msg_iter;
 new_mtu:
 	mtu = tipc_node_get_mtu(net, dnode, tsk->portid);
 	__skb_queue_head_init(&head);
@@ -980,8 +985,10 @@ new_mtu:
 			rc = dsz;
 			break;
 		}
-		if (rc == -EMSGSIZE)
+		if (rc == -EMSGSIZE) {
+			m->msg_iter = save;
 			goto new_mtu;
+		}
 		if (rc != -ELINKCONG)
 			break;
 		tsk->link_cong = 1;
@@ -1052,6 +1059,7 @@ static int tipc_send_stream(struct kiocb *iocb, struct socket *sock,
 	long timeo;
 	u32 dnode;
 	uint mtu, send, sent = 0;
+	struct iov_iter save;
 
 	/* Handle implied connection establishment */
 	if (unlikely(dest)) {
@@ -1078,6 +1086,7 @@ static int tipc_send_stream(struct kiocb *iocb, struct socket *sock,
 	dnode = tsk_peer_node(tsk);
 
 next:
+	save = m->msg_iter;
 	mtu = tsk->max_pkt;
 	send = min_t(uint, dsz - sent, TIPC_MAX_USER_MSG_SIZE);
 	__skb_queue_head_init(&head);
@@ -1097,6 +1106,7 @@ next:
 			if (rc == -EMSGSIZE) {
 				tsk->max_pkt = tipc_node_get_mtu(net, dnode,
 								 portid);
+				m->msg_iter = save;
 				goto next;
 			}
 			if (rc != -ELINKCONG)
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 13/18] net/socket.c: fold do_sock_{read,write} into callers
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 net/socket.c | 56 +++++++++++++++++++++-----------------------------------
 1 file changed, 21 insertions(+), 35 deletions(-)

diff --git a/net/socket.c b/net/socket.c
index 3326d67..4d08b50 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -845,25 +845,11 @@ static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
 	return sock->ops->splice_read(sock, ppos, pipe, len, flags);
 }
 
-static ssize_t do_sock_read(struct msghdr *msg, struct kiocb *iocb,
-		struct file *file, const struct iovec *iov,
-		unsigned long nr_segs)
-{
-	struct socket *sock = file->private_data;
-
-	msg->msg_name = NULL;
-	msg->msg_namelen = 0;
-	msg->msg_control = NULL;
-	msg->msg_controllen = 0;
-	iov_iter_init(&msg->msg_iter, READ, iov, nr_segs, iocb->ki_nbytes);
-	msg->msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
-
-	return __sock_recvmsg(iocb, sock, msg, iocb->ki_nbytes, msg->msg_flags);
-}
-
 static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
 				unsigned long nr_segs, loff_t pos)
 {
+	struct file *file = iocb->ki_filp;
+	struct socket *sock = file->private_data;
 	struct msghdr msg;
 
 	if (pos != 0)
@@ -872,36 +858,36 @@ static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
 	if (iocb->ki_nbytes == 0)	/* Match SYS5 behaviour */
 		return 0;
 
-	return do_sock_read(&msg, iocb, iocb->ki_filp, iov, nr_segs);
-}
-
-static ssize_t do_sock_write(struct msghdr *msg, struct kiocb *iocb,
-			struct file *file, const struct iovec *iov,
-			unsigned long nr_segs)
-{
-	struct socket *sock = file->private_data;
-
-	msg->msg_name = NULL;
-	msg->msg_namelen = 0;
-	msg->msg_control = NULL;
-	msg->msg_controllen = 0;
-	iov_iter_init(&msg->msg_iter, WRITE, iov, nr_segs, iocb->ki_nbytes);
-	msg->msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
-	if (sock->type == SOCK_SEQPACKET)
-		msg->msg_flags |= MSG_EOR;
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	iov_iter_init(&msg.msg_iter, READ, iov, nr_segs, iocb->ki_nbytes);
+	msg.msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
 
-	return __sock_sendmsg(iocb, sock, msg, iocb->ki_nbytes);
+	return __sock_recvmsg(iocb, sock, &msg, iocb->ki_nbytes, msg.msg_flags);
 }
 
 static ssize_t sock_aio_write(struct kiocb *iocb, const struct iovec *iov,
 			  unsigned long nr_segs, loff_t pos)
 {
+	struct file *file = iocb->ki_filp;
+	struct socket *sock = file->private_data;
 	struct msghdr msg;
 
 	if (pos != 0)
 		return -ESPIPE;
 
-	return do_sock_write(&msg, iocb, iocb->ki_filp, iov, nr_segs);
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	iov_iter_init(&msg.msg_iter, WRITE, iov, nr_segs, iocb->ki_nbytes);
+	msg.msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
+	if (sock->type == SOCK_SEQPACKET)
+		msg.msg_flags |= MSG_EOR;
+
+	return __sock_sendmsg(iocb, sock, &msg, iocb->ki_nbytes);
 }
 
 /*
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 12/18] crypto: switch af_alg_make_sg() to iov_iter
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev, linux-crypto
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

With that, all ->sendmsg() instances are converted to iov_iter primitives
and are agnostic wrt the kind of iov_iter they are working with.
So's the last remaining ->recvmsg() instance that wasn't kind-agnostic yet.
All ->sendmsg() and ->recvmsg() advance ->msg_iter by the amount actually
copied and none of them modifies the underlying iovec, etc.

Cc: linux-crypto@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 crypto/af_alg.c         | 40 ++++++++------------------
 crypto/algif_hash.c     | 45 ++++++++++++------------------
 crypto/algif_skcipher.c | 74 ++++++++++++++++++++++---------------------------
 include/crypto/if_alg.h |  3 +-
 4 files changed, 62 insertions(+), 100 deletions(-)

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 4665b79c..eb78fe8 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -338,49 +338,31 @@ static const struct net_proto_family alg_family = {
 	.owner	=	THIS_MODULE,
 };
 
-int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len,
-		   int write)
+int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len)
 {
-	unsigned long from = (unsigned long)addr;
-	unsigned long npages;
-	unsigned off;
-	int err;
-	int i;
-
-	err = -EFAULT;
-	if (!access_ok(write ? VERIFY_READ : VERIFY_WRITE, addr, len))
-		goto out;
-
-	off = from & ~PAGE_MASK;
-	npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
-	if (npages > ALG_MAX_PAGES)
-		npages = ALG_MAX_PAGES;
+	size_t off;
+	ssize_t n;
+	int npages, i;
 
-	err = get_user_pages_fast(from, npages, write, sgl->pages);
-	if (err < 0)
-		goto out;
+	n = iov_iter_get_pages(iter, sgl->pages, len, ALG_MAX_PAGES, &off);
+	if (n < 0)
+		return n;
 
-	npages = err;
-	err = -EINVAL;
+	npages = PAGE_ALIGN(off + n);
 	if (WARN_ON(npages == 0))
-		goto out;
-
-	err = 0;
+		return -EINVAL;
 
 	sg_init_table(sgl->sg, npages);
 
-	for (i = 0; i < npages; i++) {
+	for (i = 0, len = n; i < npages; i++) {
 		int plen = min_t(int, len, PAGE_SIZE - off);
 
 		sg_set_page(sgl->sg + i, sgl->pages[i], plen, off);
 
 		off = 0;
 		len -= plen;
-		err += plen;
 	}
-
-out:
-	return err;
+	return n;
 }
 EXPORT_SYMBOL_GPL(af_alg_make_sg);
 
diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
index 01f56eb..01da360 100644
--- a/crypto/algif_hash.c
+++ b/crypto/algif_hash.c
@@ -41,8 +41,6 @@ static int hash_sendmsg(struct kiocb *unused, struct socket *sock,
 	struct sock *sk = sock->sk;
 	struct alg_sock *ask = alg_sk(sk);
 	struct hash_ctx *ctx = ask->private;
-	unsigned long iovlen;
-	const struct iovec *iov;
 	long copied = 0;
 	int err;
 
@@ -58,37 +56,28 @@ static int hash_sendmsg(struct kiocb *unused, struct socket *sock,
 
 	ctx->more = 0;
 
-	for (iov = msg->msg_iter.iov, iovlen = msg->msg_iter.nr_segs; iovlen > 0;
-	     iovlen--, iov++) {
-		unsigned long seglen = iov->iov_len;
-		char __user *from = iov->iov_base;
+	while (iov_iter_count(&msg->msg_iter)) {
+		int len = iov_iter_count(&msg->msg_iter);
 
-		while (seglen) {
-			int len = min_t(unsigned long, seglen, limit);
-			int newlen;
+		if (len > limit)
+			len = limit;
 
-			newlen = af_alg_make_sg(&ctx->sgl, from, len, 0);
-			if (newlen < 0) {
-				err = copied ? 0 : newlen;
-				goto unlock;
-			}
-
-			ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL,
-						newlen);
-
-			err = af_alg_wait_for_completion(
-				crypto_ahash_update(&ctx->req),
-				&ctx->completion);
+		len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
+		if (len < 0) {
+			err = copied ? 0 : len;
+			goto unlock;
+		}
 
-			af_alg_free_sg(&ctx->sgl);
+		ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);
 
-			if (err)
-				goto unlock;
+		err = af_alg_wait_for_completion(crypto_ahash_update(&ctx->req),
+						 &ctx->completion);
+		af_alg_free_sg(&ctx->sgl);
+		if (err)
+			goto unlock;
 
-			seglen -= newlen;
-			from += newlen;
-			copied += newlen;
-		}
+		copied += len;
+		iov_iter_advance(&msg->msg_iter, len);
 	}
 
 	err = 0;
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index c12207c..37110fd 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -426,67 +426,59 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock,
 		&ctx->req));
 	struct skcipher_sg_list *sgl;
 	struct scatterlist *sg;
-	unsigned long iovlen;
-	const struct iovec *iov;
 	int err = -EAGAIN;
 	int used;
 	long copied = 0;
 
 	lock_sock(sk);
-	for (iov = msg->msg_iter.iov, iovlen = msg->msg_iter.nr_segs; iovlen > 0;
-	     iovlen--, iov++) {
-		unsigned long seglen = iov->iov_len;
-		char __user *from = iov->iov_base;
-
-		while (seglen) {
-			sgl = list_first_entry(&ctx->tsgl,
-					       struct skcipher_sg_list, list);
-			sg = sgl->sg;
-
-			while (!sg->length)
-				sg++;
-
-			if (!ctx->used) {
-				err = skcipher_wait_for_data(sk, flags);
-				if (err)
-					goto unlock;
-			}
+	while (iov_iter_count(&msg->msg_iter)) {
+		sgl = list_first_entry(&ctx->tsgl,
+				       struct skcipher_sg_list, list);
+		sg = sgl->sg;
 
-			used = min_t(unsigned long, ctx->used, seglen);
+		while (!sg->length)
+			sg++;
 
-			used = af_alg_make_sg(&ctx->rsgl, from, used, 1);
-			err = used;
-			if (err < 0)
+		used = ctx->used;
+		if (!used) {
+			err = skcipher_wait_for_data(sk, flags);
+			if (err)
 				goto unlock;
+		}
+
+		used = min_t(unsigned long, used, iov_iter_count(&msg->msg_iter));
+
+		used = af_alg_make_sg(&ctx->rsgl, &msg->msg_iter, used);
+		err = used;
+		if (err < 0)
+			goto unlock;
 
-			if (ctx->more || used < ctx->used)
-				used -= used % bs;
+		if (ctx->more || used < ctx->used)
+			used -= used % bs;
 
-			err = -EINVAL;
-			if (!used)
-				goto free;
+		err = -EINVAL;
+		if (!used)
+			goto free;
 
-			ablkcipher_request_set_crypt(&ctx->req, sg,
-						     ctx->rsgl.sg, used,
-						     ctx->iv);
+		ablkcipher_request_set_crypt(&ctx->req, sg,
+					     ctx->rsgl.sg, used,
+					     ctx->iv);
 
-			err = af_alg_wait_for_completion(
+		err = af_alg_wait_for_completion(
 				ctx->enc ?
 					crypto_ablkcipher_encrypt(&ctx->req) :
 					crypto_ablkcipher_decrypt(&ctx->req),
 				&ctx->completion);
 
 free:
-			af_alg_free_sg(&ctx->rsgl);
+		af_alg_free_sg(&ctx->rsgl);
 
-			if (err)
-				goto unlock;
+		if (err)
+			goto unlock;
 
-			copied += used;
-			from += used;
-			seglen -= used;
-			skcipher_pull_sgl(sk, used);
-		}
+		copied += used;
+		skcipher_pull_sgl(sk, used);
+		iov_iter_advance(&msg->msg_iter, used);
 	}
 
 	err = 0;
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index cd62bf4..88ea64e 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -67,8 +67,7 @@ int af_alg_unregister_type(const struct af_alg_type *type);
 int af_alg_release(struct socket *sock);
 int af_alg_accept(struct sock *sk, struct socket *newsock);
 
-int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len,
-		   int write);
+int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len);
 void af_alg_free_sg(struct af_alg_sgl *sgl);
 
 int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con);
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 11/18] net: bury net/core/iovec.c - nothing in there is used anymore
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/linux/socket.h |   7 ---
 net/core/Makefile      |   2 +-
 net/core/iovec.c       | 137 -------------------------------------------------
 3 files changed, 1 insertion(+), 145 deletions(-)
 delete mode 100644 net/core/iovec.c

diff --git a/include/linux/socket.h b/include/linux/socket.h
index 6e49a14..5c19cba 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -318,13 +318,6 @@ struct ucred {
 /* IPX options */
 #define IPX_TYPE	1
 
-extern int csum_partial_copy_fromiovecend(unsigned char *kdata, 
-					  struct iovec *iov, 
-					  int offset, 
-					  unsigned int len, __wsum *csump);
-extern unsigned long iov_pages(const struct iovec *iov, int offset,
-			       unsigned long nr_segs);
-
 extern int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr);
 extern int put_cmsg(struct msghdr*, int level, int type, int len, void *data);
 
diff --git a/net/core/Makefile b/net/core/Makefile
index 235e6c5..fec0856 100644
--- a/net/core/Makefile
+++ b/net/core/Makefile
@@ -2,7 +2,7 @@
 # Makefile for the Linux networking core.
 #
 
-obj-y := sock.o request_sock.o skbuff.o iovec.o datagram.o stream.o scm.o \
+obj-y := sock.o request_sock.o skbuff.o datagram.o stream.o scm.o \
 	 gen_stats.o gen_estimator.o net_namespace.o secure_seq.o flow_dissector.o
 
 obj-$(CONFIG_SYSCTL) += sysctl_net_core.o
diff --git a/net/core/iovec.c b/net/core/iovec.c
deleted file mode 100644
index dcbe98b..0000000
--- a/net/core/iovec.c
+++ /dev/null
@@ -1,137 +0,0 @@
-/*
- *	iovec manipulation routines.
- *
- *
- *		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.
- *
- *	Fixes:
- *		Andrew Lunn	:	Errors in iovec copying.
- *		Pedro Roque	:	Added memcpy_fromiovecend and
- *					csum_..._fromiovecend.
- *		Andi Kleen	:	fixed error handling for 2.1
- *		Alexey Kuznetsov:	2.1 optimisations
- *		Andi Kleen	:	Fix csum*fromiovecend for IPv6.
- */
-
-#include <linux/errno.h>
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/net.h>
-#include <linux/in6.h>
-#include <asm/uaccess.h>
-#include <asm/byteorder.h>
-#include <net/checksum.h>
-#include <net/sock.h>
-
-/*
- *	And now for the all-in-one: copy and checksum from a user iovec
- *	directly to a datagram
- *	Calls to csum_partial but the last must be in 32 bit chunks
- *
- *	ip_build_xmit must ensure that when fragmenting only the last
- *	call to this function will be unaligned also.
- */
-int csum_partial_copy_fromiovecend(unsigned char *kdata, struct iovec *iov,
-				 int offset, unsigned int len, __wsum *csump)
-{
-	__wsum csum = *csump;
-	int partial_cnt = 0, err = 0;
-
-	/* Skip over the finished iovecs */
-	while (offset >= iov->iov_len) {
-		offset -= iov->iov_len;
-		iov++;
-	}
-
-	while (len > 0) {
-		u8 __user *base = iov->iov_base + offset;
-		int copy = min_t(unsigned int, len, iov->iov_len - offset);
-
-		offset = 0;
-
-		/* There is a remnant from previous iov. */
-		if (partial_cnt) {
-			int par_len = 4 - partial_cnt;
-
-			/* iov component is too short ... */
-			if (par_len > copy) {
-				if (copy_from_user(kdata, base, copy))
-					goto out_fault;
-				kdata += copy;
-				base += copy;
-				partial_cnt += copy;
-				len -= copy;
-				iov++;
-				if (len)
-					continue;
-				*csump = csum_partial(kdata - partial_cnt,
-							 partial_cnt, csum);
-				goto out;
-			}
-			if (copy_from_user(kdata, base, par_len))
-				goto out_fault;
-			csum = csum_partial(kdata - partial_cnt, 4, csum);
-			kdata += par_len;
-			base  += par_len;
-			copy  -= par_len;
-			len   -= par_len;
-			partial_cnt = 0;
-		}
-
-		if (len > copy) {
-			partial_cnt = copy % 4;
-			if (partial_cnt) {
-				copy -= partial_cnt;
-				if (copy_from_user(kdata + copy, base + copy,
-						partial_cnt))
-					goto out_fault;
-			}
-		}
-
-		if (copy) {
-			csum = csum_and_copy_from_user(base, kdata, copy,
-							csum, &err);
-			if (err)
-				goto out;
-		}
-		len   -= copy + partial_cnt;
-		kdata += copy + partial_cnt;
-		iov++;
-	}
-	*csump = csum;
-out:
-	return err;
-
-out_fault:
-	err = -EFAULT;
-	goto out;
-}
-EXPORT_SYMBOL(csum_partial_copy_fromiovecend);
-
-unsigned long iov_pages(const struct iovec *iov, int offset,
-			unsigned long nr_segs)
-{
-	unsigned long seg, base;
-	int pages = 0, len, size;
-
-	while (nr_segs && (offset >= iov->iov_len)) {
-		offset -= iov->iov_len;
-		++iov;
-		--nr_segs;
-	}
-
-	for (seg = 0; seg < nr_segs; seg++) {
-		base = (unsigned long)iov[seg].iov_base + offset;
-		len = iov[seg].iov_len - offset;
-		size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT;
-		pages += size;
-		offset = 0;
-	}
-
-	return pages;
-}
-EXPORT_SYMBOL(iov_pages);
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 09/18] net: switch memcpy_fromiovec()/memcpy_fromiovecend() users to copy_from_iter()
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

That takes care of the majority of ->sendmsg() instances - most of them
via memcpy_to_msg() or assorted getfrag() callbacks.  One place where we
still keep memcpy_fromiovecend() is tipc - there we potentially read the
same data over and over; separate patch, that...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/linux/skbuff.h |  3 +--
 include/net/udplite.h  |  3 +--
 net/ipv4/ip_output.c   |  6 ++----
 net/ipv4/ping.c        | 14 +++++++-------
 net/ipv4/raw.c         |  2 +-
 net/ipv4/tcp_input.c   |  2 +-
 net/ipv6/raw.c         |  2 +-
 7 files changed, 14 insertions(+), 18 deletions(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 9a8bafe..b349c96 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2692,8 +2692,7 @@ int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci);
 
 static inline int memcpy_from_msg(void *data, struct msghdr *msg, int len)
 {
-	/* XXX: stripping const */
-	return memcpy_fromiovec(data, (struct iovec *)msg->msg_iter.iov, len);
+	return copy_from_iter(data, len, &msg->msg_iter) == len ? 0 : -EFAULT;
 }
 
 static inline int memcpy_to_msg(struct msghdr *msg, void *data, int len)
diff --git a/include/net/udplite.h b/include/net/udplite.h
index ae7c8d1..8076193 100644
--- a/include/net/udplite.h
+++ b/include/net/udplite.h
@@ -20,8 +20,7 @@ static __inline__ int udplite_getfrag(void *from, char *to, int  offset,
 				      int len, int odd, struct sk_buff *skb)
 {
 	struct msghdr *msg = from;
-	/* XXX: stripping const */
-	return memcpy_fromiovecend(to, (struct iovec *)msg->msg_iter.iov, offset, len);
+	return copy_from_iter(to, len, &msg->msg_iter) != len ? -EFAULT : 0;
 }
 
 /* Designate sk as UDP-Lite socket */
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index b50861b2..f998bc8 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -755,13 +755,11 @@ ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, struct sk
 	struct msghdr *msg = from;
 
 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
-		/* XXX: stripping const */
-		if (memcpy_fromiovecend(to, (struct iovec *)msg->msg_iter.iov, offset, len) < 0)
+		if (copy_from_iter(to, len, &msg->msg_iter) != len)
 			return -EFAULT;
 	} else {
 		__wsum csum = 0;
-		/* XXX: stripping const */
-		if (csum_partial_copy_fromiovecend(to, (struct iovec *)msg->msg_iter.iov, offset, len, &csum) < 0)
+		if (csum_and_copy_from_iter(to, len, &csum, &msg->msg_iter) != len)
 			return -EFAULT;
 		skb->csum = csum_block_add(skb->csum, csum, odd);
 	}
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 9e15ba7..e9f66e1 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -599,18 +599,18 @@ int ping_getfrag(void *from, char *to,
 	struct pingfakehdr *pfh = (struct pingfakehdr *)from;
 
 	if (offset == 0) {
-		if (fraglen < sizeof(struct icmphdr))
+		fraglen -= sizeof(struct icmphdr);
+		if (fraglen < 0)
 			BUG();
-		if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
-			    pfh->msg->msg_iter.iov, 0, fraglen - sizeof(struct icmphdr),
-			    &pfh->wcheck))
+		if (csum_and_copy_from_iter(to + sizeof(struct icmphdr),
+			    fraglen, &pfh->wcheck,
+			    &pfh->msg->msg_iter) != fraglen)
 			return -EFAULT;
 	} else if (offset < sizeof(struct icmphdr)) {
 			BUG();
 	} else {
-		if (csum_partial_copy_fromiovecend
-				(to, pfh->msg->msg_iter.iov, offset - sizeof(struct icmphdr),
-				 fraglen, &pfh->wcheck))
+		if (csum_and_copy_from_iter(to, fraglen, &pfh->wcheck,
+					    &pfh->msg->msg_iter) != fraglen)
 			return -EFAULT;
 	}
 
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 2c9d252..f027a70 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -382,7 +382,7 @@ static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
 
 	skb->transport_header = skb->network_header;
 	err = -EFAULT;
-	if (memcpy_fromiovecend((void *)iph, msg->msg_iter.iov, 0, length))
+	if (memcpy_from_msg(iph, msg, length))
 		goto error_free;
 
 	iphlen = iph->ihl * 4;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 93c7482..71fb37c 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4368,7 +4368,7 @@ int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size)
 	if (tcp_try_rmem_schedule(sk, skb, skb->truesize))
 		goto err_free;
 
-	if (copy_from_iter(skb_put(skb, size), size, &msg->msg_iter) != size)
+	if (memcpy_from_msg(skb_put(skb, size), msg, size))
 		goto err_free;
 
 	TCP_SKB_CB(skb)->seq = tcp_sk(sk)->rcv_nxt;
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 0dbb328..dae7f1a 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -648,7 +648,7 @@ static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
 	skb->ip_summed = CHECKSUM_NONE;
 
 	skb->transport_header = skb->network_header;
-	err = memcpy_fromiovecend((void *)iph, msg->msg_iter.iov, 0, length);
+	err = memcpy_from_msg(iph, msg, length);
 	if (err)
 		goto error_fault;
 
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 08/18] ip: convert tcp_sendmsg() to iov_iter primitives
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

patch is actually smaller than it seems to be - most of it is unindenting
the inner loop body in tcp_sendmsg() itself...

the bit in tcp_input.c is going to get reverted very soon - that's what
memcpy_from_msg() will become, but not in this commit; let's keep it
reasonably contained...

There's one potentially subtle change here: in case of short copy from
userland, mainline tcp_send_syn_data() discards the skb it has allocated
and falls back to normal path, where we'll send as much as possible after
rereading the same data again.  This patch trims SYN+data skb instead -
that way we don't need to copy from the same place twice.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/net/sock.h    |  18 ++--
 net/ipv4/tcp.c        | 233 +++++++++++++++++++++++---------------------------
 net/ipv4/tcp_input.c  |   2 +-
 net/ipv4/tcp_output.c |  11 ++-
 4 files changed, 123 insertions(+), 141 deletions(-)

diff --git a/include/net/sock.h b/include/net/sock.h
index 1534149..1e45e59 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1803,27 +1803,25 @@ static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
 }
 
 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
-					   char __user *from, char *to,
+					   struct iov_iter *from, char *to,
 					   int copy, int offset)
 {
 	if (skb->ip_summed == CHECKSUM_NONE) {
-		int err = 0;
-		__wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
-		if (err)
-			return err;
+		__wsum csum = 0;
+		if (csum_and_copy_from_iter(to, copy, &csum, from) != copy)
+			return -EFAULT;
 		skb->csum = csum_block_add(skb->csum, csum, offset);
 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
-		if (!access_ok(VERIFY_READ, from, copy) ||
-		    __copy_from_user_nocache(to, from, copy))
+		if (copy_from_iter_nocache(to, copy, from) != copy)
 			return -EFAULT;
-	} else if (copy_from_user(to, from, copy))
+	} else if (copy_from_iter(to, copy, from) != copy)
 		return -EFAULT;
 
 	return 0;
 }
 
 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
-				       char __user *from, int copy)
+				       struct iov_iter *from, int copy)
 {
 	int err, offset = skb->len;
 
@@ -1835,7 +1833,7 @@ static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
 	return err;
 }
 
-static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
+static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
 					   struct sk_buff *skb,
 					   struct page *page,
 					   int off, int copy)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 3075723..9d72a0f 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1067,11 +1067,10 @@ static int tcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg,
 int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		size_t size)
 {
-	const struct iovec *iov;
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct sk_buff *skb;
-	int iovlen, flags, err, copied = 0;
-	int mss_now = 0, size_goal, copied_syn = 0, offset = 0;
+	int flags, err, copied = 0;
+	int mss_now = 0, size_goal, copied_syn = 0;
 	bool sg;
 	long timeo;
 
@@ -1084,7 +1083,6 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 			goto out;
 		else if (err)
 			goto out_err;
-		offset = copied_syn;
 	}
 
 	timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
@@ -1118,8 +1116,6 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 	mss_now = tcp_send_mss(sk, &size_goal, flags);
 
 	/* Ok commence sending. */
-	iovlen = msg->msg_iter.nr_segs;
-	iov = msg->msg_iter.iov;
 	copied = 0;
 
 	err = -EPIPE;
@@ -1128,151 +1124,134 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
 	sg = !!(sk->sk_route_caps & NETIF_F_SG);
 
-	while (--iovlen >= 0) {
-		size_t seglen = iov->iov_len;
-		unsigned char __user *from = iov->iov_base;
+	while (iov_iter_count(&msg->msg_iter)) {
+		int copy = 0;
+		int max = size_goal;
 
-		iov++;
-		if (unlikely(offset > 0)) {  /* Skip bytes copied in SYN */
-			if (offset >= seglen) {
-				offset -= seglen;
-				continue;
-			}
-			seglen -= offset;
-			from += offset;
-			offset = 0;
+		skb = tcp_write_queue_tail(sk);
+		if (tcp_send_head(sk)) {
+			if (skb->ip_summed == CHECKSUM_NONE)
+				max = mss_now;
+			copy = max - skb->len;
 		}
 
-		while (seglen > 0) {
-			int copy = 0;
-			int max = size_goal;
-
-			skb = tcp_write_queue_tail(sk);
-			if (tcp_send_head(sk)) {
-				if (skb->ip_summed == CHECKSUM_NONE)
-					max = mss_now;
-				copy = max - skb->len;
-			}
-
-			if (copy <= 0) {
+		if (copy <= 0) {
 new_segment:
-				/* Allocate new segment. If the interface is SG,
-				 * allocate skb fitting to single page.
-				 */
-				if (!sk_stream_memory_free(sk))
-					goto wait_for_sndbuf;
+			/* Allocate new segment. If the interface is SG,
+			 * allocate skb fitting to single page.
+			 */
+			if (!sk_stream_memory_free(sk))
+				goto wait_for_sndbuf;
 
-				skb = sk_stream_alloc_skb(sk,
-							  select_size(sk, sg),
-							  sk->sk_allocation);
-				if (!skb)
-					goto wait_for_memory;
+			skb = sk_stream_alloc_skb(sk,
+						  select_size(sk, sg),
+						  sk->sk_allocation);
+			if (!skb)
+				goto wait_for_memory;
 
-				/*
-				 * Check whether we can use HW checksum.
-				 */
-				if (sk->sk_route_caps & NETIF_F_ALL_CSUM)
-					skb->ip_summed = CHECKSUM_PARTIAL;
+			/*
+			 * Check whether we can use HW checksum.
+			 */
+			if (sk->sk_route_caps & NETIF_F_ALL_CSUM)
+				skb->ip_summed = CHECKSUM_PARTIAL;
 
-				skb_entail(sk, skb);
-				copy = size_goal;
-				max = size_goal;
+			skb_entail(sk, skb);
+			copy = size_goal;
+			max = size_goal;
 
-				/* All packets are restored as if they have
-				 * already been sent. skb_mstamp isn't set to
-				 * avoid wrong rtt estimation.
-				 */
-				if (tp->repair)
-					TCP_SKB_CB(skb)->sacked |= TCPCB_REPAIRED;
-			}
+			/* All packets are restored as if they have
+			 * already been sent. skb_mstamp isn't set to
+			 * avoid wrong rtt estimation.
+			 */
+			if (tp->repair)
+				TCP_SKB_CB(skb)->sacked |= TCPCB_REPAIRED;
+		}
 
-			/* Try to append data to the end of skb. */
-			if (copy > seglen)
-				copy = seglen;
-
-			/* Where to copy to? */
-			if (skb_availroom(skb) > 0) {
-				/* We have some space in skb head. Superb! */
-				copy = min_t(int, copy, skb_availroom(skb));
-				err = skb_add_data_nocache(sk, skb, from, copy);
-				if (err)
-					goto do_fault;
-			} else {
-				bool merge = true;
-				int i = skb_shinfo(skb)->nr_frags;
-				struct page_frag *pfrag = sk_page_frag(sk);
-
-				if (!sk_page_frag_refill(sk, pfrag))
-					goto wait_for_memory;
-
-				if (!skb_can_coalesce(skb, i, pfrag->page,
-						      pfrag->offset)) {
-					if (i == MAX_SKB_FRAGS || !sg) {
-						tcp_mark_push(tp, skb);
-						goto new_segment;
-					}
-					merge = false;
-				}
+		/* Try to append data to the end of skb. */
+		if (copy > iov_iter_count(&msg->msg_iter))
+			copy = iov_iter_count(&msg->msg_iter);
+
+		/* Where to copy to? */
+		if (skb_availroom(skb) > 0) {
+			/* We have some space in skb head. Superb! */
+			copy = min_t(int, copy, skb_availroom(skb));
+			err = skb_add_data_nocache(sk, skb, &msg->msg_iter, copy);
+			if (err)
+				goto do_fault;
+		} else {
+			bool merge = true;
+			int i = skb_shinfo(skb)->nr_frags;
+			struct page_frag *pfrag = sk_page_frag(sk);
+
+			if (!sk_page_frag_refill(sk, pfrag))
+				goto wait_for_memory;
 
-				copy = min_t(int, copy, pfrag->size - pfrag->offset);
-
-				if (!sk_wmem_schedule(sk, copy))
-					goto wait_for_memory;
-
-				err = skb_copy_to_page_nocache(sk, from, skb,
-							       pfrag->page,
-							       pfrag->offset,
-							       copy);
-				if (err)
-					goto do_error;
-
-				/* Update the skb. */
-				if (merge) {
-					skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
-				} else {
-					skb_fill_page_desc(skb, i, pfrag->page,
-							   pfrag->offset, copy);
-					get_page(pfrag->page);
+			if (!skb_can_coalesce(skb, i, pfrag->page,
+					      pfrag->offset)) {
+				if (i == MAX_SKB_FRAGS || !sg) {
+					tcp_mark_push(tp, skb);
+					goto new_segment;
 				}
-				pfrag->offset += copy;
+				merge = false;
 			}
 
-			if (!copied)
-				TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH;
+			copy = min_t(int, copy, pfrag->size - pfrag->offset);
 
-			tp->write_seq += copy;
-			TCP_SKB_CB(skb)->end_seq += copy;
-			tcp_skb_pcount_set(skb, 0);
+			if (!sk_wmem_schedule(sk, copy))
+				goto wait_for_memory;
 
-			from += copy;
-			copied += copy;
-			if ((seglen -= copy) == 0 && iovlen == 0) {
-				tcp_tx_timestamp(sk, skb);
-				goto out;
+			err = skb_copy_to_page_nocache(sk, &msg->msg_iter, skb,
+						       pfrag->page,
+						       pfrag->offset,
+						       copy);
+			if (err)
+				goto do_error;
+
+			/* Update the skb. */
+			if (merge) {
+				skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
+			} else {
+				skb_fill_page_desc(skb, i, pfrag->page,
+						   pfrag->offset, copy);
+				get_page(pfrag->page);
 			}
+			pfrag->offset += copy;
+		}
 
-			if (skb->len < max || (flags & MSG_OOB) || unlikely(tp->repair))
-				continue;
+		if (!copied)
+			TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH;
+
+		tp->write_seq += copy;
+		TCP_SKB_CB(skb)->end_seq += copy;
+		tcp_skb_pcount_set(skb, 0);
+
+		copied += copy;
+		if (!iov_iter_count(&msg->msg_iter)) {
+			tcp_tx_timestamp(sk, skb);
+			goto out;
+		}
 
-			if (forced_push(tp)) {
-				tcp_mark_push(tp, skb);
-				__tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH);
-			} else if (skb == tcp_send_head(sk))
-				tcp_push_one(sk, mss_now);
+		if (skb->len < max || (flags & MSG_OOB) || unlikely(tp->repair))
 			continue;
 
+		if (forced_push(tp)) {
+			tcp_mark_push(tp, skb);
+			__tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH);
+		} else if (skb == tcp_send_head(sk))
+			tcp_push_one(sk, mss_now);
+		continue;
+
 wait_for_sndbuf:
-			set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
+		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
 wait_for_memory:
-			if (copied)
-				tcp_push(sk, flags & ~MSG_MORE, mss_now,
-					 TCP_NAGLE_PUSH, size_goal);
+		if (copied)
+			tcp_push(sk, flags & ~MSG_MORE, mss_now,
+				 TCP_NAGLE_PUSH, size_goal);
 
-			if ((err = sk_stream_wait_memory(sk, &timeo)) != 0)
-				goto do_error;
+		if ((err = sk_stream_wait_memory(sk, &timeo)) != 0)
+			goto do_error;
 
-			mss_now = tcp_send_mss(sk, &size_goal, flags);
-		}
+		mss_now = tcp_send_mss(sk, &size_goal, flags);
 	}
 
 out:
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 71fb37c..93c7482 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4368,7 +4368,7 @@ int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size)
 	if (tcp_try_rmem_schedule(sk, skb, skb->truesize))
 		goto err_free;
 
-	if (memcpy_from_msg(skb_put(skb, size), msg, size))
+	if (copy_from_iter(skb_put(skb, size), size, &msg->msg_iter) != size)
 		goto err_free;
 
 	TCP_SKB_CB(skb)->seq = tcp_sk(sk)->rcv_nxt;
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 20ab06b..722c8bc 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3055,7 +3055,7 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct tcp_fastopen_request *fo = tp->fastopen_req;
-	int syn_loss = 0, space, err = 0;
+	int syn_loss = 0, space, err = 0, copied;
 	unsigned long last_syn_loss = 0;
 	struct sk_buff *syn_data;
 
@@ -3093,11 +3093,16 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)
 		goto fallback;
 	syn_data->ip_summed = CHECKSUM_PARTIAL;
 	memcpy(syn_data->cb, syn->cb, sizeof(syn->cb));
-	if (unlikely(memcpy_fromiovecend(skb_put(syn_data, space),
-					 fo->data->msg_iter.iov, 0, space))) {
+	copied = copy_from_iter(skb_put(syn_data, space), space,
+				&fo->data->msg_iter);
+	if (unlikely(!copied)) {
 		kfree_skb(syn_data);
 		goto fallback;
 	}
+	if (copied != space) {
+		skb_trim(syn_data, copied);
+		space = copied;
+	}
 
 	/* No more data pending in inet_wait_for_connect() */
 	if (space == fo->size)
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 14/18] net: switch sockets to ->read_iter/->write_iter
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 net/socket.c | 56 +++++++++++++++++++++++++++-----------------------------
 1 file changed, 27 insertions(+), 29 deletions(-)

diff --git a/net/socket.c b/net/socket.c
index 4d08b50..bbedbfc 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -113,10 +113,8 @@ unsigned int sysctl_net_busy_read __read_mostly;
 unsigned int sysctl_net_busy_poll __read_mostly;
 #endif
 
-static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
-			 unsigned long nr_segs, loff_t pos);
-static ssize_t sock_aio_write(struct kiocb *iocb, const struct iovec *iov,
-			  unsigned long nr_segs, loff_t pos);
+static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to);
+static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from);
 static int sock_mmap(struct file *file, struct vm_area_struct *vma);
 
 static int sock_close(struct inode *inode, struct file *file);
@@ -142,8 +140,10 @@ static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
 static const struct file_operations socket_file_ops = {
 	.owner =	THIS_MODULE,
 	.llseek =	no_llseek,
-	.aio_read =	sock_aio_read,
-	.aio_write =	sock_aio_write,
+	.read =		new_sync_read,
+	.write =	new_sync_write,
+	.read_iter =	sock_read_iter,
+	.write_iter =	sock_write_iter,
 	.poll =		sock_poll,
 	.unlocked_ioctl = sock_ioctl,
 #ifdef CONFIG_COMPAT
@@ -845,49 +845,47 @@ static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
 	return sock->ops->splice_read(sock, ppos, pipe, len, flags);
 }
 
-static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
-				unsigned long nr_segs, loff_t pos)
+static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
 {
 	struct file *file = iocb->ki_filp;
 	struct socket *sock = file->private_data;
-	struct msghdr msg;
+	struct msghdr msg = {.msg_iter = *to};
+	ssize_t res;
+
+	if (file->f_flags & O_NONBLOCK)
+		msg.msg_flags = MSG_DONTWAIT;
 
-	if (pos != 0)
+	if (iocb->ki_pos != 0)
 		return -ESPIPE;
 
 	if (iocb->ki_nbytes == 0)	/* Match SYS5 behaviour */
 		return 0;
 
-	msg.msg_name = NULL;
-	msg.msg_namelen = 0;
-	msg.msg_control = NULL;
-	msg.msg_controllen = 0;
-	iov_iter_init(&msg.msg_iter, READ, iov, nr_segs, iocb->ki_nbytes);
-	msg.msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
-
-	return __sock_recvmsg(iocb, sock, &msg, iocb->ki_nbytes, msg.msg_flags);
+	res = __sock_recvmsg(iocb, sock, &msg,
+			     iocb->ki_nbytes, msg.msg_flags);
+	*to = msg.msg_iter;
+	return res;
 }
 
-static ssize_t sock_aio_write(struct kiocb *iocb, const struct iovec *iov,
-			  unsigned long nr_segs, loff_t pos)
+static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
 {
 	struct file *file = iocb->ki_filp;
 	struct socket *sock = file->private_data;
-	struct msghdr msg;
+	struct msghdr msg = {.msg_iter = *from};
+	ssize_t res;
 
-	if (pos != 0)
+	if (iocb->ki_pos != 0)
 		return -ESPIPE;
 
-	msg.msg_name = NULL;
-	msg.msg_namelen = 0;
-	msg.msg_control = NULL;
-	msg.msg_controllen = 0;
-	iov_iter_init(&msg.msg_iter, WRITE, iov, nr_segs, iocb->ki_nbytes);
-	msg.msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
+	if (file->f_flags & O_NONBLOCK)
+		msg.msg_flags = MSG_DONTWAIT;
+
 	if (sock->type == SOCK_SEQPACKET)
 		msg.msg_flags |= MSG_EOR;
 
-	return __sock_sendmsg(iocb, sock, &msg, iocb->ki_nbytes);
+	res = __sock_sendmsg(iocb, sock, &msg, iocb->ki_nbytes);
+	*from = msg.msg_iter;
+	return res;
 }
 
 /*
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 15/18] vhost: switch vhost get_indirect() to iov_iter, kill memcpy_fromiovec()
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev, Michael S. Tsirkin, kvm
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 drivers/vhost/vhost.c |  6 ++++--
 include/linux/uio.h   |  1 -
 lib/iovec.c           | 25 -------------------------
 3 files changed, 4 insertions(+), 28 deletions(-)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index cb807d0..2ee2826 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1125,6 +1125,7 @@ static int get_indirect(struct vhost_virtqueue *vq,
 	struct vring_desc desc;
 	unsigned int i = 0, count, found = 0;
 	u32 len = vhost32_to_cpu(vq, indirect->len);
+	struct iov_iter from;
 	int ret;
 
 	/* Sanity check */
@@ -1142,6 +1143,7 @@ static int get_indirect(struct vhost_virtqueue *vq,
 		vq_err(vq, "Translation failure %d in indirect.\n", ret);
 		return ret;
 	}
+	iov_iter_init(&from, READ, vq->indirect, ret, len);
 
 	/* We will use the result as an address to read from, so most
 	 * architectures only need a compiler barrier here. */
@@ -1164,8 +1166,8 @@ static int get_indirect(struct vhost_virtqueue *vq,
 			       i, count);
 			return -EINVAL;
 		}
-		if (unlikely(memcpy_fromiovec((unsigned char *)&desc,
-					      vq->indirect, sizeof desc))) {
+		if (unlikely(copy_from_iter(&desc, sizeof(desc), &from) !=
+			     sizeof(desc))) {
 			vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n",
 			       i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc);
 			return -EINVAL;
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 1c5e453..af3439f 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -135,7 +135,6 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count)
 size_t csum_and_copy_to_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 
-int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len);
 int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov,
 			int offset, int len);
 int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata,
diff --git a/lib/iovec.c b/lib/iovec.c
index 2d99cb4..4a90875 100644
--- a/lib/iovec.c
+++ b/lib/iovec.c
@@ -3,31 +3,6 @@
 #include <linux/uio.h>
 
 /*
- *	Copy iovec to kernel. Returns -EFAULT on error.
- *
- *	Note: this modifies the original iovec.
- */
-
-int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len)
-{
-	while (len > 0) {
-		if (iov->iov_len) {
-			int copy = min_t(unsigned int, len, iov->iov_len);
-			if (copy_from_user(kdata, iov->iov_base, copy))
-				return -EFAULT;
-			len -= copy;
-			kdata += copy;
-			iov->iov_base += copy;
-			iov->iov_len -= copy;
-		}
-		iov++;
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL(memcpy_fromiovec);
-
-/*
  *	Copy kernel to iovec. Returns -EFAULT on error.
  */
 
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 16/18] vhost: don't bother with copying iovec in handle_tx()
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev, Michael S. Tsirkin, kvm
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

just advance the msg.msg_iter and be done with that.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 drivers/vhost/net.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 6906f76..d86cc9b 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -336,7 +336,7 @@ static void handle_tx(struct vhost_net *net)
 {
 	struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX];
 	struct vhost_virtqueue *vq = &nvq->vq;
-	unsigned out, in, s;
+	unsigned out, in;
 	int head;
 	struct msghdr msg = {
 		.msg_name = NULL,
@@ -395,16 +395,17 @@ static void handle_tx(struct vhost_net *net)
 			break;
 		}
 		/* Skip header. TODO: support TSO. */
-		s = move_iovec_hdr(vq->iov, nvq->hdr, hdr_size, out);
 		len = iov_length(vq->iov, out);
 		iov_iter_init(&msg.msg_iter, WRITE, vq->iov, out, len);
+		iov_iter_advance(&msg.msg_iter, hdr_size);
 		/* Sanity check */
-		if (!len) {
+		if (!iov_iter_count(&msg.msg_iter)) {
 			vq_err(vq, "Unexpected header len for TX: "
 			       "%zd expected %zd\n",
-			       iov_length(nvq->hdr, s), hdr_size);
+			       len, hdr_size);
 			break;
 		}
+		len = iov_iter_count(&msg.msg_iter);
 
 		zcopy_used = zcopy && len >= VHOST_GOODCOPY_LEN
 				   && (nvq->upend_idx + 1) % UIO_MAXIOV !=
-- 
2.1.4

^ permalink raw reply related

* [PATCH v2 17/18] vhost: don't bother copying iovecs in handle_rx(), kill memcpy_toiovecend()
From: Al Viro @ 2015-02-02  7:59 UTC (permalink / raw)
  To: David Miller; +Cc: netdev, Michael S. Tsirkin, kvm
In-Reply-To: <20150131035513.GK29656@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 drivers/vhost/net.c | 79 ++++++++++++++---------------------------------------
 include/linux/uio.h |  3 --
 lib/iovec.c         | 26 ------------------
 3 files changed, 20 insertions(+), 88 deletions(-)

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index d86cc9b..73c0ebf 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -84,10 +84,6 @@ struct vhost_net_ubuf_ref {
 
 struct vhost_net_virtqueue {
 	struct vhost_virtqueue vq;
-	/* hdr is used to store the virtio header.
-	 * Since each iovec has >= 1 byte length, we never need more than
-	 * header length entries to store the header. */
-	struct iovec hdr[sizeof(struct virtio_net_hdr_mrg_rxbuf)];
 	size_t vhost_hlen;
 	size_t sock_hlen;
 	/* vhost zerocopy support fields below: */
@@ -235,44 +231,6 @@ static bool vhost_sock_zcopy(struct socket *sock)
 		sock_flag(sock->sk, SOCK_ZEROCOPY);
 }
 
-/* Pop first len bytes from iovec. Return number of segments used. */
-static int move_iovec_hdr(struct iovec *from, struct iovec *to,
-			  size_t len, int iov_count)
-{
-	int seg = 0;
-	size_t size;
-
-	while (len && seg < iov_count) {
-		size = min(from->iov_len, len);
-		to->iov_base = from->iov_base;
-		to->iov_len = size;
-		from->iov_len -= size;
-		from->iov_base += size;
-		len -= size;
-		++from;
-		++to;
-		++seg;
-	}
-	return seg;
-}
-/* Copy iovec entries for len bytes from iovec. */
-static void copy_iovec_hdr(const struct iovec *from, struct iovec *to,
-			   size_t len, int iovcount)
-{
-	int seg = 0;
-	size_t size;
-
-	while (len && seg < iovcount) {
-		size = min(from->iov_len, len);
-		to->iov_base = from->iov_base;
-		to->iov_len = size;
-		len -= size;
-		++from;
-		++to;
-		++seg;
-	}
-}
-
 /* In case of DMA done not in order in lower device driver for some reason.
  * upend_idx is used to track end of used idx, done_idx is used to track head
  * of used idx. Once lower device DMA done contiguously, we will signal KVM
@@ -570,9 +528,9 @@ static void handle_rx(struct vhost_net *net)
 		.msg_controllen = 0,
 		.msg_flags = MSG_DONTWAIT,
 	};
-	struct virtio_net_hdr_mrg_rxbuf hdr = {
-		.hdr.flags = 0,
-		.hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE
+	struct virtio_net_hdr hdr = {
+		.flags = 0,
+		.gso_type = VIRTIO_NET_HDR_GSO_NONE
 	};
 	size_t total_len = 0;
 	int err, mergeable;
@@ -580,6 +538,7 @@ static void handle_rx(struct vhost_net *net)
 	size_t vhost_hlen, sock_hlen;
 	size_t vhost_len, sock_len;
 	struct socket *sock;
+	struct iov_iter fixup;
 
 	mutex_lock(&vq->mutex);
 	sock = vq->private_data;
@@ -624,14 +583,17 @@ static void handle_rx(struct vhost_net *net)
 			break;
 		}
 		/* We don't need to be notified again. */
-		if (unlikely((vhost_hlen)))
-			/* Skip header. TODO: support TSO. */
-			move_iovec_hdr(vq->iov, nvq->hdr, vhost_hlen, in);
-		else
-			/* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF:
-			 * needed because recvmsg can modify msg_iov. */
-			copy_iovec_hdr(vq->iov, nvq->hdr, sock_hlen, in);
-		iov_iter_init(&msg.msg_iter, READ, vq->iov, in, sock_len);
+		iov_iter_init(&msg.msg_iter, READ, vq->iov, in, vhost_len);
+		fixup = msg.msg_iter;
+		if (unlikely((vhost_hlen))) {
+			/* We will supply the header ourselves
+			 * TODO: support TSO. */
+			iov_iter_advance(&msg.msg_iter, vhost_hlen);
+		} else {
+			/* It'll come from socket; we'll need to patch
+			 * ->num_buffers over if VIRTIO_NET_F_MRG_RXBUF */
+			iov_iter_advance(&fixup, sizeof(hdr));
+		}
 		err = sock->ops->recvmsg(NULL, sock, &msg,
 					 sock_len, MSG_DONTWAIT | MSG_TRUNC);
 		/* Userspace might have consumed the packet meanwhile:
@@ -643,18 +605,17 @@ static void handle_rx(struct vhost_net *net)
 			vhost_discard_vq_desc(vq, headcount);
 			continue;
 		}
+		/* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */
 		if (unlikely(vhost_hlen) &&
-		    memcpy_toiovecend(nvq->hdr, (unsigned char *)&hdr, 0,
-				      vhost_hlen)) {
+		    copy_to_iter(&hdr, sizeof(hdr), &fixup) != sizeof(hdr)) {
 			vq_err(vq, "Unable to write vnet_hdr at addr %p\n",
 			       vq->iov->iov_base);
 			break;
 		}
-		/* TODO: Should check and handle checksum. */
+		/* Supply (or replace) ->num_buffers if VIRTIO_NET_F_MRG_RXBUF
+		 * TODO: Should check and handle checksum. */
 		if (likely(mergeable) &&
-		    memcpy_toiovecend(nvq->hdr, (unsigned char *)&headcount,
-				      offsetof(typeof(hdr), num_buffers),
-				      sizeof hdr.num_buffers)) {
+		    copy_to_iter(&headcount, 2, &fixup) != 2) {
 			vq_err(vq, "Failed num_buffers write");
 			vhost_discard_vq_desc(vq, headcount);
 			break;
diff --git a/include/linux/uio.h b/include/linux/uio.h
index af3439f..02bd8a9 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -137,7 +137,4 @@ size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct io
 
 int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov,
 			int offset, int len);
-int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata,
-		      int offset, int len);
-
 #endif
diff --git a/lib/iovec.c b/lib/iovec.c
index 4a90875..d8f17a9 100644
--- a/lib/iovec.c
+++ b/lib/iovec.c
@@ -3,32 +3,6 @@
 #include <linux/uio.h>
 
 /*
- *	Copy kernel to iovec. Returns -EFAULT on error.
- */
-
-int memcpy_toiovecend(const struct iovec *iov, unsigned char *kdata,
-		      int offset, int len)
-{
-	int copy;
-	for (; len > 0; ++iov) {
-		/* Skip over the finished iovecs */
-		if (unlikely(offset >= iov->iov_len)) {
-			offset -= iov->iov_len;
-			continue;
-		}
-		copy = min_t(unsigned int, iov->iov_len - offset, len);
-		if (copy_to_user(iov->iov_base + offset, kdata, copy))
-			return -EFAULT;
-		offset = 0;
-		kdata += copy;
-		len -= copy;
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL(memcpy_toiovecend);
-
-/*
  *	Copy iovec to kernel. Returns -EFAULT on error.
  */
 
-- 
2.1.4

^ permalink raw reply related

* Re: [RFC][PATCHSET] more iov_iter conversion in net/*
From: Al Viro @ 2015-02-02  8:01 UTC (permalink / raw)
  To: David Miller; +Cc: netdev
In-Reply-To: <20150202065339.GU29656@ZenIV.linux.org.uk>

On Mon, Feb 02, 2015 at 06:53:39AM +0000, Al Viro wrote:

> Al, off to figure out the proper Cc: for all those commits, so that
> git-send-email would DTRT - if I need to edit commit messages, might
> as well do that at the same time...

Done, vfs.git#for-davem force-pushed; same contents, all changes are in
commit messages.

^ permalink raw reply

* Question: should local address be expired when updating PMTU?
From: shengyong @ 2015-02-02  8:20 UTC (permalink / raw)
  To: davem; +Cc: netdev, yangyingling, steffen.klassert, hannes

Hi, David Miller
Since commit 81aded246 (ipv6: Handle PMTU in ICMP error handlers), the entries
in neigh table may get expired. But in the situation:

          Host only
    PC <------------> Virtual Machine

a packet is sent from PC to VM, and the packet looks like:
-----------------------------------
| IPv6 (src=PC-addr, dst=VM-addr) |
|---------------------------------|
|     ICMPv6 (Packet Too Big)     |
|---------------------------------|
| IPv6 (src=VM-addr, dst=VM-addr) |
|---------------------------------|
| ICMPv6 (Neighbor Advertisement) |
-----------------------------------

Then the local addr on VM will be updated with an expire value. After the
lifetime of the local addr is expired, the VM is unreachable from PC.

	# ip -6 route list table local
	local fe80::1 dev lo  metric 0 *expire 596*

I find that the current code seems not check whether the entry is a local one
when doing PMTU update. And if the following code is added, the situation could
be avoided.

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index b2614b2..b80317a 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1136,6 +1136,9 @@ static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
 {
        struct rt6_info *rt6 = (struct rt6_info*)dst;

+       if (rt6->rt6i_flags & RTF_LOCAL)
+               return;
+
        dst_confirm(dst);
        if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
                struct net *net = dev_net(dst->dev);

So is this modification correct? Or how can we avoid such expiring?

thx & BR,
Sheng

^ permalink raw reply related

* Re: [PATCH] tun: orphan an skb on tx
From: Steffen Klassert @ 2015-02-02  8:24 UTC (permalink / raw)
  To: David Woodhouse
  Cc: David Miller, mst, herbert, eric.dumazet, jan.kiszka, netdev,
	linux-kernel, qemu-devel
In-Reply-To: <1422862030.11044.86.camel@infradead.org>

On Mon, Feb 02, 2015 at 07:27:10AM +0000, David Woodhouse wrote:
> On Sun, 2015-02-01 at 21:07 -0800, David Miller wrote:
> 
> > We might as well have not have implemented the IPSEC stack at all,
> > because as a result of the userland VPN stuff our IPSEC stack is
> > largely unused except by a very narrow group of users.
> 
> Well, I'd love to make better use of it if I can. I do suspect it makes
> most sense for userspace to continue to manage the probing of UDP
> connectivity, and the fallback to TCP mode — and I suspect it also makes
> sense to continue to use tun for passing packets up to the VPN client
> when it's using the TCP transport.
> 
> So the question would be how we handle redirecting the packet flow to
> the optional UDP transport, when the VPN client determines that it's
> available. For the sake of the user setting up firewall and routing
> rules, I do think it's important that it continues to appear to
> userspace as the *same* device for the entire lifetime of the session,
> regardless of which transport the packets happen to be using at a given
> moment in time. It doesn't *have* to be tun, though. 
> 
> You don't seem to like my suggestion of somehow pushing down an XFRM
> state to the tun device to direct the packets out there instead of up to
> userspace. Do you have an alternative suggestion... or a specific
> concern that would help me come up with something you like better?

Maybe you want to use a virtual tunnel interface (vti) what we have
already. Everything that is routed through such an interface is
guaranteed to be either encrypted if a matching xfrm state is present
or dropped. Same on the rceive side, everything that is received by
this interface is guaranteed to be IPsec processed. So you can do
a routing based decision about the IPsec processing.

While I'm sure it could handle the ESP in UDP encapsulation, I'm not that
sure about your TCP fallback because this requires a valid xfrm state
to allow packets to pass. Using the same interface for both is probably
not possible.

^ permalink raw reply

* Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host
From: Steffen Klassert @ 2015-02-02  8:44 UTC (permalink / raw)
  To: Nicolas Dichtel; +Cc: Fan Du, herbert, davem, netdev, fengyuleidian0615
In-Reply-To: <54CA0B9F.8080104@6wind.com>

On Thu, Jan 29, 2015 at 11:29:51AM +0100, Nicolas Dichtel wrote:
> A way to solve this problem was to provide to userland a xfrm compat header
> file, which match the ABI of the kernel. Something like:
> 
> #include <linux/xfrm.h>
> 
> #define xfrm_usersa_info xfrm_usersa_info_64
> #define xfrm_usersa_info_compat xfrm_usersa_info
> struct xfrm_usersa_info_compat {
> 	struct xfrm_selector		sel;
> 	struct xfrm_id			id;
> 	xfrm_address_t			saddr;
> 	struct xfrm_lifetime_cfg	lft;
> 	struct xfrm_lifetime_cur	curlft;
> 	struct xfrm_stats		stats;
> 	__u32				seq;
> 	__u32				reqid;
> 	__u16				family;
> 	__u8				mode;
> 	__u8				replay_window;
> 	__u8				flags;
> 	__u8				hole1;
> 	__u32				hole2;
> };
> 
> The point I try to make is that patching userland apps allows to use xfrm on a
> 32bits userland / 64bits kernel.

Ugh, I did not know that this is used that way. Which applications do this?
So the situation is worse than I thought. What happens to such applications
if we add a compat layer in the kernel? I'd guess they will break, right?

> 
> If I understand well your patch, it will not be possible anymore, all messages
> will be rejected. And this may break existing apps.

This patch would have been a quick solution without the case you
mentioned. Now I fear we can't fix all cases, something will remain
broken.

^ permalink raw reply


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