* [PATCH 1/3] net: introduce new socket support: xensock
2014-08-08 11:32 [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers Oleksandr Dmytryshyn
@ 2014-08-08 11:32 ` Oleksandr Dmytryshyn
2014-08-08 11:32 ` [PATCH 2/3] xen-sockback: add support of the xen-sockback driver Oleksandr Dmytryshyn
` (4 subsequent siblings)
5 siblings, 0 replies; 12+ messages in thread
From: Oleksandr Dmytryshyn @ 2014-08-08 11:32 UTC (permalink / raw)
To: Ian Campbell, Stefano Stabellini, Tim Deegan, xen-devel
Those sockets will be used for the xen-sock frontend/backend
drivers. Those drivers will allow to connect via xensock
sockets (in this case dom0/domD sockets can be used for the
server application and domU sockets can be used for the
client application).
Signed-off-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>
---
drivers/net/Kconfig | 4 +
drivers/net/Makefile | 2 +
drivers/net/xensock/Makefile | 5 +
drivers/net/xensock/xensock-dev.c | 269 +++++++++++++
drivers/net/xensock/xensock-proto.c | 767 ++++++++++++++++++++++++++++++++++++
include/linux/socket.h | 4 +-
include/net/af_xensock.h | 46 +++
include/net/xensock.h | 130 ++++++
net/core/sock.c | 9 +-
9 files changed, 1232 insertions(+), 4 deletions(-)
create mode 100644 drivers/net/xensock/Makefile
create mode 100644 drivers/net/xensock/xensock-dev.c
create mode 100644 drivers/net/xensock/xensock-proto.c
create mode 100644 include/net/af_xensock.h
create mode 100644 include/net/xensock.h
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 89402c3..420981a 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -348,6 +348,10 @@ config XEN_NETDEV_BACKEND
compile this driver as a module, chose M here: the module
will be called xen-netback.
+config XEN_SOCKDEV_PROTO
+ bool
+ default n
+
config VMXNET3
tristate "VMware VMXNET3 ethernet driver"
depends on PCI && INET
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 3fef8a8..43bf910 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -61,6 +61,8 @@ obj-$(CONFIG_VMXNET3) += vmxnet3/
obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
obj-$(CONFIG_XEN_NETDEV_BACKEND) += xen-netback/
+obj-$(CONFIG_XEN_SOCKDEV_PROTO) += xensock/
+
obj-$(CONFIG_USB_CATC) += usb/
obj-$(CONFIG_USB_KAWETH) += usb/
obj-$(CONFIG_USB_PEGASUS) += usb/
diff --git a/drivers/net/xensock/Makefile b/drivers/net/xensock/Makefile
new file mode 100644
index 0000000..d70db09
--- /dev/null
+++ b/drivers/net/xensock/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for the xensock driver
+#
+
+obj-$(CONFIG_XEN_SOCKDEV_PROTO) := xensock-proto.o xensock-dev.o
diff --git a/drivers/net/xensock/xensock-dev.c b/drivers/net/xensock/xensock-dev.c
new file mode 100644
index 0000000..6da8f34
--- /dev/null
+++ b/drivers/net/xensock/xensock-dev.c
@@ -0,0 +1,269 @@
+/*
+ * Xen socket dev driver.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <linux/skbuff.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+
+#include <net/af_xensock.h>
+
+LIST_HEAD(xensock_list);
+DEFINE_RWLOCK(xensock_list_lock);
+DECLARE_WAIT_QUEUE_HEAD(xensock_accept_wait);
+
+static inline void xensock_lock_dev(struct xen_sock_dev *dev)
+{
+ spin_lock(&dev->lock);
+}
+
+static inline void xensock_unlock_dev(struct xen_sock_dev *dev)
+{
+ spin_unlock(&dev->lock);
+}
+
+struct xen_sock_dev *alloc_xen_sock_dev(int sizeof_priv, const char *name)
+{
+ struct xen_sock_dev *dev;
+ int alloc_size;
+ struct xen_sock_dev *p;
+
+ BUG_ON(strlen(name) >= sizeof(dev->name));
+
+ alloc_size = sizeof(struct xen_sock_dev);
+
+ if (sizeof_priv) {
+ alloc_size = ALIGN(sizeof(struct xen_sock_dev), SOCKDEV_ALIGN);
+ alloc_size += sizeof_priv;
+ }
+
+ /* ensure 32-byte alignment of whole construct */
+ alloc_size += SOCKDEV_ALIGN - 1;
+
+ p = kzalloc(alloc_size, GFP_KERNEL);
+ if (!p) {
+ pr_err("alloc_xen_sock_dev: Unable to allocate device\n");
+ return NULL;
+ }
+
+ dev = PTR_ALIGN(p, SOCKDEV_ALIGN);
+ dev->padded = (char *)dev - (char *)p;
+
+ strcpy(dev->name, name);
+ spin_lock_init(&dev->lock);
+ sockif_carrier_off(dev);
+ sockif_stop_queue(dev);
+
+ return dev;
+}
+EXPORT_SYMBOL(alloc_xen_sock_dev);
+
+void free_xen_sock_dev(struct xen_sock_dev *dev)
+{
+ if (!dev)
+ return;
+
+ kfree((char *)dev - dev->padded);
+}
+EXPORT_SYMBOL(free_xen_sock_dev);
+
+
+int xensock_register_dev(struct xen_sock_dev *dev)
+{
+ write_lock_bh(&xensock_list_lock);
+ list_add_tail(&dev->list, &xensock_list);
+ write_unlock_bh(&xensock_list_lock);
+ wake_up_interruptible(&xensock_accept_wait);
+
+ return 0;
+}
+EXPORT_SYMBOL(xensock_register_dev);
+
+static void __xensock_dev_unlink_sk(struct xen_sock_dev *dev);
+
+void xensock_unregister_dev(struct xen_sock_dev *dev)
+{
+ write_lock_bh(&xensock_list_lock);
+ xensock_lock_dev(dev);
+ __xensock_dev_unlink_sk(dev);
+ list_del(&dev->list);
+ xensock_unlock_dev(dev);
+ write_unlock_bh(&xensock_list_lock);
+}
+EXPORT_SYMBOL(xensock_unregister_dev);
+
+static int __xensock_dev_link_sk(struct xen_sock_dev *dev, struct sock *sk)
+{
+ sock_hold(sk);
+ dev->sk = sk;
+ xen_sk(sk)->dev = dev;
+
+ return 0;
+}
+
+static void __xensock_dev_unlink_sk(struct xen_sock_dev *dev)
+{
+ struct sock *sk = dev->sk;
+ struct socket *sock;
+
+ if (sk) {
+ sock = sk->sk_socket;
+ sock->state = SS_UNCONNECTED;
+
+ xen_sk(sk)->dev = NULL;
+ dev->sk = NULL;
+ sk->sk_err = ENOTCONN;
+ sk->sk_state_change(sk);
+ sock_put(sk);
+ }
+}
+
+void xensock_dev_unlink_sk(struct xen_sock_dev *dev)
+{
+ write_lock_bh(&xensock_list_lock);
+ xensock_lock_dev(dev);
+ __xensock_dev_unlink_sk(dev);
+ xensock_unlock_dev(dev);
+ write_unlock_bh(&xensock_list_lock);
+ wake_up_interruptible(&xensock_accept_wait);
+}
+
+void xensock_unlink_all_dev_sk(void)
+{
+ struct xen_sock_dev *ldev;
+
+ write_lock_bh(&xensock_list_lock);
+ list_for_each_entry(ldev, &xensock_list, list) {
+ xensock_lock_dev(ldev);
+ __xensock_dev_unlink_sk(ldev);
+ xensock_unlock_dev(ldev);
+ }
+ write_unlock_bh(&xensock_list_lock);
+}
+
+int xensock_dev_wait(struct sock *sk, struct sock *nsk)
+{
+ int rc = 0;
+ long timeout = sk->sk_rcvtimeo;
+ struct xen_sock_dev *ldev;
+ bool dev_found;
+
+ DECLARE_WAITQUEUE(wait, current);
+
+ add_wait_queue_exclusive(&xensock_accept_wait, &wait);
+ for (;;) {
+ __set_current_state(TASK_INTERRUPTIBLE);
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ break;
+ rc = -ERESTARTSYS;
+ if (signal_pending(current))
+ break;
+ rc = -EAGAIN;
+ if (!timeout)
+ break;
+ rc = 0;
+ dev_found = false;
+ read_lock_bh(&xensock_list_lock);
+ list_for_each_entry(ldev, &xensock_list, list) {
+ xensock_lock_dev(ldev);
+ if (ldev->sk == NULL) {
+ __xensock_dev_link_sk(ldev, nsk);
+ xensock_unlock_dev(ldev);
+ dev_found = true;
+ break;
+ }
+ xensock_unlock_dev(ldev);
+ }
+ read_unlock_bh(&xensock_list_lock);
+ if (dev_found)
+ break;
+
+ release_sock(sk);
+ timeout = schedule_timeout(timeout);
+ lock_sock(sk);
+ }
+ __set_current_state(TASK_RUNNING);
+ remove_wait_queue(&xensock_accept_wait, &wait);
+
+ return rc;
+}
+
+/* xensock_dev_send - transmit a xensock frame
+ * @skb: pointer to socket buffer with xensock frame in data section
+ */
+int xensock_dev_send(struct sk_buff *skb, struct xen_sock_dev *dev)
+{
+ int err = -EINVAL;
+
+ /* Make sure the xensock frame can pass the selected xensock device */
+ if (unlikely(skb->len > XENSOCK_MTU)) {
+ err = -EMSGSIZE;
+ goto inval_skb;
+ }
+
+ if (unlikely(!dev->start_xmit)) {
+ err = -EIO;
+ goto inval_skb;
+ }
+
+ if (sockif_queue_stopped(dev)) {
+ err = -ENOBUFS;
+ goto inval_skb;
+ }
+
+ err = dev->start_xmit(skb, dev);
+ if (err)
+ goto inval_skb;
+
+ return 0;
+
+inval_skb:
+ kfree_skb(skb);
+ return err;
+}
+
+int xensock_dev_queue_rx_skb(struct sk_buff *skb, struct xen_sock_dev *dev)
+{
+ int rc = -ENETDOWN;
+ struct sock *sk = dev->sk;
+
+ xensock_lock_dev(dev);
+ if (sk == NULL)
+ goto out;
+
+ rc = 0;
+ skb_queue_tail(&sk->sk_receive_queue, skb);
+ if (!sock_flag(sk, SOCK_DEAD))
+ sk->sk_data_ready(sk, skb->len);
+out:
+ xensock_unlock_dev(dev);
+ return rc;
+}
diff --git a/drivers/net/xensock/xensock-proto.c b/drivers/net/xensock/xensock-proto.c
new file mode 100644
index 0000000..d05e5d5
--- /dev/null
+++ b/drivers/net/xensock/xensock-proto.c
@@ -0,0 +1,767 @@
+/*
+ * Xen socket protocol driver.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <linux/skbuff.h>
+#include <linux/if_arp.h>
+#include <linux/highmem.h>
+
+#include <net/tcp_states.h>
+#include <net/af_xensock.h>
+
+#define XENSOCK_DISCONNECT BIT(0)
+
+struct xensock_skb_cb {
+ unsigned int flags_checked;
+};
+
+/* Return pointer to store the extra msg flags for xensock_proto_recvmsg().
+ * We use the space of one unsigned int beyond the 'int' size
+ * in skb->cb. Xensock frontend and backend drivers are using this
+ * first 'int' part of the skb->cb.
+ */
+static inline struct xensock_skb_cb *xensock_proto_cb(struct sk_buff *skb)
+{
+ BUILD_BUG_ON(sizeof(skb->cb) <= (sizeof(int) +
+ sizeof(struct xensock_skb_cb)));
+
+ /* return pointer after 'int' size */
+ return (struct xensock_skb_cb *)(&((int *)skb->cb)[1]);
+}
+
+static int xensock_prot_init(struct sock *sk)
+{
+ return 0;
+}
+
+static struct proto xensock_proto __read_mostly = {
+ .name = "XENSOCK",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct xen_sock),
+ .init = xensock_prot_init,
+};
+
+struct sock *xen_allocate_sock(struct net *net)
+{
+ struct xen_sock *xsk;
+ struct sock *sk;
+
+ sk = sk_alloc(net, PF_XENSOCK, GFP_KERNEL, &xensock_proto);
+
+ if (!sk)
+ goto out;
+
+ sock_init_data(NULL, sk);
+
+ xsk = xen_sk(sk);
+ xsk->dev = NULL;
+out:
+ return sk;
+}
+
+static struct sock *xensock_make_new(struct sock *osk)
+{
+ struct sock *sk = NULL;
+
+ if (osk->sk_type != SOCK_RAW)
+ goto out;
+
+ sk = xen_allocate_sock(sock_net(osk));
+ if (sk == NULL)
+ goto out;
+
+ sk->sk_type = osk->sk_type;
+ sk->sk_priority = osk->sk_priority;
+ sk->sk_protocol = osk->sk_protocol;
+ sk->sk_rcvbuf = osk->sk_rcvbuf;
+ sk->sk_sndbuf = osk->sk_sndbuf;
+ sk->sk_state = TCP_ESTABLISHED;
+ sk->sk_backlog_rcv = osk->sk_backlog_rcv;
+ sock_copy_flags(sk, osk);
+
+out:
+ return sk;
+}
+
+static int xensock_prot_connect(struct socket *sock, struct sockaddr *uaddr,
+ int addr_len, int flags)
+{
+ struct sock *sk;
+ int rc;
+
+ if (sock->state == SS_CONNECTED)
+ return 0;
+
+ sk = sock->sk;
+
+ lock_sock(sk);
+ rc = xensock_dev_wait(sk, sk);
+
+ if (!rc)
+ sock->state = SS_CONNECTED;
+
+ release_sock(sk);
+
+ return rc;
+}
+
+static int xensock_prot_accept(struct socket *sock, struct socket *newsock,
+ int flags)
+{
+ struct sock *nsk, *sk = sock->sk;
+ int rc = -EINVAL;
+
+ if (!sk)
+ goto out;
+
+ rc = -EOPNOTSUPP;
+ if (sk->sk_type != SOCK_RAW)
+ goto out;
+
+ lock_sock(sk);
+ rc = -EINVAL;
+ if (sk->sk_state != TCP_LISTEN)
+ goto err_release_sk;
+
+ rc = -ENOMEM;
+ nsk = xensock_make_new(sk);
+ if (!nsk)
+ goto err_release_sk;
+
+ rc = xensock_dev_wait(sk, nsk);
+ if (rc)
+ goto err_remove_nsk;
+
+ sock_graft(nsk, newsock);
+
+ /* Now attach up the new socket */
+ sk->sk_ack_backlog--;
+ newsock->state = SS_CONNECTED;
+ rc = 0;
+err_release_sk:
+ release_sock(sk);
+out:
+ return rc;
+
+err_remove_nsk:
+ sock_orphan(nsk);
+ sock_put(nsk);
+ goto err_release_sk;
+}
+
+static int xensock_prot_listen(struct socket *sock, int backlog)
+{
+ struct sock *sk = sock->sk;
+ int rc = -EOPNOTSUPP;
+
+ lock_sock(sk);
+ /* All created sockets (in .accept callback) will have a non
+ * NULL pointer and listen operation for them is prohibited.
+ */
+ if (xen_sk(sk)->dev)
+ goto out;
+
+ if (sk->sk_state != TCP_LISTEN) {
+ sk->sk_max_ack_backlog = backlog;
+ sk->sk_state = TCP_LISTEN;
+ rc = 0;
+ }
+out:
+ release_sock(sk);
+
+ return rc;
+}
+
+static int xensock_prot_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct xen_sock_dev *dev;
+ struct sk_buff *skb;
+ unsigned char xflag;
+ int err;
+
+ if (!sk)
+ return 0;
+
+ lock_sock(sk);
+ dev = xen_sk(sk)->dev;
+
+ if (dev) {
+ release_sock(sk);
+ skb = sock_alloc_send_skb(sk, 1, 0, &err);
+ lock_sock(sk);
+ if (!skb)
+ goto skip_send_no_con;
+
+ xflag = XENSOCK_DISCONNECT;
+ memcpy(skb_put(skb, 1), &xflag, 1);
+ skb->dev = NULL;
+ skb->sk = sk;
+
+ err = xensock_dev_send(skb, dev);
+
+ if (err)
+ kfree_skb(skb);
+
+skip_send_no_con:
+ xensock_dev_unlink_sk(dev);
+ }
+
+ /* Flush the recv buffs */
+ while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL)
+ __kfree_skb(skb);
+
+ sock_orphan(sk);
+ sock->sk = NULL;
+
+ release_sock(sk);
+ sock_put(sk);
+
+ return 0;
+}
+
+int xensock_prot_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+ struct sock *sk = sock->sk;
+
+ switch (cmd) {
+ case SIOCGSTAMP:
+ return sock_get_timestamp(sk, (struct timeval __user *)arg);
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static int xensock_prot_sendmsg(struct kiocb *iocb, struct socket *sock,
+ struct msghdr *msg, size_t size)
+{
+ struct sock *sk = sock->sk;
+ struct xen_sock_dev *dev;
+ struct sk_buff *skb;
+ int err;
+ unsigned char xflag;
+ size_t sent = 0;
+ unsigned int header_len, data_len;
+ unsigned int chunk;
+
+ if (msg->msg_flags & MSG_OOB)
+ return -EOPNOTSUPP;
+
+ lock_sock(sk);
+
+ err = sock_error(sk);
+ if (err)
+ goto out;
+
+ err = -ENOTCONN;
+
+ dev = xen_sk(sk)->dev;
+ if (!dev)
+ goto out;
+
+ /* Another side has closed connection */
+ if (sock->state == SS_DISCONNECTING) {
+ err = size;
+ goto out;
+ }
+
+ if (sock->state != SS_CONNECTED)
+ goto out;
+
+ if (size == 0) {
+ err = 0;
+ goto out;
+ }
+
+ do {
+ chunk = size + 1;
+
+ if (chunk > XENSOCK_MTU)
+ chunk = XENSOCK_MTU;
+
+ if (chunk <= PAGE_SIZE) {
+ header_len = chunk;
+ data_len = 0;
+ } else {
+ header_len = PAGE_SIZE;
+ data_len = chunk - PAGE_SIZE;
+ }
+
+ release_sock(sk);
+ skb = sock_alloc_send_pskb(sk, header_len, data_len,
+ msg->msg_flags & MSG_DONTWAIT,
+ &err);
+ lock_sock(sk);
+ if (!skb)
+ goto out;
+
+ xflag = 0;
+ memcpy(skb_tail_pointer(skb), &xflag, 1);
+
+ skb->data_len = data_len;
+ skb->len = chunk;
+
+ err = skb_copy_datagram_from_iovec(skb, 1, msg->msg_iov,
+ sent, chunk - 1);
+ if (err < 0)
+ goto free_skb;
+
+ /* move pointers in the skb */
+ skb->tail += header_len;
+
+ err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
+ if (err < 0)
+ goto free_skb;
+
+ skb->dev = NULL;
+ skb->sk = sk;
+
+ err = xensock_dev_send(skb, dev);
+
+ if (err)
+ goto free_skb;
+
+ /* First byte of the SKB data is the xensock flags */
+ chunk--;
+
+ sent += chunk;
+ size -= chunk;
+ } while (size);
+
+ err = sent;
+out:
+ release_sock(sk);
+ return err;
+
+free_skb:
+ kfree_skb(skb);
+ goto out;
+}
+
+static long xen_sock_data_wait(struct sock *sk, long timeo)
+{
+ DECLARE_WAITQUEUE(wait, current);
+
+ add_wait_queue(sk_sleep(sk), &wait);
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ if (!skb_queue_empty(&sk->sk_receive_queue))
+ break;
+
+ if (sk->sk_err || (sk->sk_shutdown & RCV_SHUTDOWN))
+ break;
+
+ if (signal_pending(current) || !timeo)
+ break;
+
+ set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+ release_sock(sk);
+ timeo = schedule_timeout(timeo);
+ lock_sock(sk);
+ clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+ }
+
+ __set_current_state(TASK_RUNNING);
+ remove_wait_queue(sk_sleep(sk), &wait);
+ return timeo;
+}
+
+static unsigned char get_skb_xflags(struct sk_buff *skb)
+{
+ unsigned char ret;
+ int i;
+ int nr_frags;
+ int skb_len = skb_headlen(skb);
+
+ if (1 <= skb_len) {
+ ret = skb->data[0];
+ __skb_pull(skb, 1);
+ return ret;
+ } else {
+ struct sk_buff *frag1;
+
+ skb_walk_frags(skb, frag1) {
+ if (frag1->len) {
+ skb->len -= 1;
+ skb->data_len -= 1;
+ ret = frag1->data[0];
+ __skb_pull(frag1, 1);
+ return ret;
+ }
+ }
+
+ nr_frags = skb_shinfo(skb)->nr_frags;
+ for (i = 0; i < nr_frags; i++) {
+ skb_frag_t *frag2;
+
+ frag2 = &skb_shinfo(skb)->frags[i];
+ if (skb_frag_size(frag2)) {
+ struct page *page = skb_frag_page(frag2);
+ u8 *vaddr;
+
+ vaddr = kmap(page);
+ ret = vaddr[frag2->page_offset];
+ kunmap(page);
+ skb->len -= 1;
+ skb->data_len -= 1;
+ skb_frag_size_sub(frag2, 1);
+ frag2->page_offset += 1;
+ return ret;
+ }
+ }
+ }
+ return 0;
+}
+
+static int xensock_prot_recvmsg(struct kiocb *iocb, struct socket *sock,
+ struct msghdr *msg, size_t size, int flags)
+{
+ struct sock *sk = sock->sk;
+ int err = 0;
+ size_t target, copied = 0;
+ long timeo;
+ int i;
+ struct sk_buff *skb;
+ int nr_frags;
+ unsigned char xflags;
+ struct xensock_skb_cb *scb;
+ struct xen_sock_dev *dev = xen_sk(sk)->dev;
+
+ if (flags & MSG_OOB)
+ return -EOPNOTSUPP;
+
+ msg->msg_namelen = 0;
+
+ lock_sock(sk);
+
+ if (!dev) {
+ copied = -ENOTCONN;
+ goto out;
+ }
+
+ if (sock->state == SS_DISCONNECTING)
+ goto out_disconnecting_state;
+
+ target = sock_rcvlowat(sk, flags & MSG_WAITALL, size);
+ timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
+
+ do {
+ int chunk;
+
+ skb = skb_dequeue(&sk->sk_receive_queue);
+ if (!skb) {
+ if (copied >= target)
+ break;
+
+ err = sock_error(sk);
+ if (err)
+ break;
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ break;
+
+ err = -EAGAIN;
+ if (!timeo)
+ break;
+
+ timeo = xen_sock_data_wait(sk, timeo);
+
+ if (signal_pending(current)) {
+ err = sock_intr_errno(timeo);
+ goto out;
+ }
+ continue;
+ }
+
+ scb = xensock_proto_cb(skb);
+
+ if (!scb->flags_checked) {
+ /* First byte of the SKB data is the xensock flags */
+ if (skb->len < 1) {
+ copied = -EFAULT;
+ break;
+ }
+
+ scb->flags_checked = 1;
+
+ xflags = get_skb_xflags(skb);
+ if (xflags & XENSOCK_DISCONNECT) {
+ sock->state = SS_DISCONNECTING;
+ xensock_dev_unlink_sk(dev);
+ goto out_disconnecting_state;
+ }
+ }
+
+ chunk = min_t(unsigned int, skb->len, size);
+ if (skb_copy_datagram_iovec(skb, 0, msg->msg_iov, chunk)) {
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ if (!copied)
+ copied = -EFAULT;
+ break;
+ }
+ copied += chunk;
+ size -= chunk;
+
+ sock_recv_ts_and_drops(msg, sk, skb);
+
+ if (!(flags & MSG_PEEK)) {
+ int skb_len = skb_headlen(skb);
+
+ if (chunk <= skb_len) {
+ __skb_pull(skb, chunk);
+ } else {
+ struct sk_buff *frag1;
+
+ __skb_pull(skb, skb_len);
+ chunk -= skb_len;
+
+ skb_walk_frags(skb, frag1) {
+ if (chunk <= frag1->len) {
+ /* Pulling partial data */
+ skb->len -= chunk;
+ skb->data_len -= chunk;
+ __skb_pull(frag1, chunk);
+ break;
+ } else if (frag1->len) {
+ /* Pulling all frag data */
+ chunk -= frag1->len;
+ skb->len -= frag1->len;
+ skb->data_len -= frag1->len;
+ __skb_pull(frag1, frag1->len);
+ }
+ }
+
+ nr_frags = skb_shinfo(skb)->nr_frags;
+ for (i = 0; i < nr_frags; i++) {
+ skb_frag_t *frag2;
+ unsigned int frag_size;
+
+ frag2 = &skb_shinfo(skb)->frags[i];
+ frag_size = skb_frag_size(frag2);
+
+ if (chunk <= frag_size) {
+ /* Pulling partial data */
+ skb->len -= chunk;
+ skb->data_len -= chunk;
+ skb_frag_size_sub(frag2, chunk);
+ frag2->page_offset += chunk;
+ break;
+ } else if (frag_size) {
+ /* Pulling all frag data */
+ chunk -= frag_size;
+ skb->len -= frag_size;
+ skb->data_len -= frag_size;
+ skb_frag_size_set(frag2, 0);
+ }
+ }
+ }
+
+ if (skb->len) {
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ break;
+ }
+ kfree_skb(skb);
+
+ } else {
+ /* put message back and return */
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ break;
+ }
+ } while (size);
+out:
+ release_sock(sk);
+ return copied ? : err;
+
+out_disconnecting_state:
+ /* Flush the recv buffs */
+ while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL)
+ __kfree_skb(skb);
+
+ err = 0;
+ copied = 0;
+ goto out;
+}
+
+static const struct proto_ops xen_sock_server_ops = {
+ .family = PF_XENSOCK,
+ .release = xensock_prot_release,
+ .bind = sock_no_bind,
+ .connect = sock_no_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = xensock_prot_accept,
+ .getname = sock_no_getname,
+ .poll = sock_no_poll,
+ .ioctl = xensock_prot_ioctl,
+ .listen = xensock_prot_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = sock_no_setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = xensock_prot_sendmsg,
+ .recvmsg = xensock_prot_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static const struct proto_ops xen_sock_client_ops = {
+ .family = PF_XENSOCK,
+ .release = xensock_prot_release,
+ .bind = sock_no_bind,
+ .connect = xensock_prot_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = sock_no_getname,
+ .poll = sock_no_poll,
+ .ioctl = xensock_prot_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = sock_no_setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = xensock_prot_sendmsg,
+ .recvmsg = xensock_prot_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static void xensock_destruct(struct sock *sk)
+{
+}
+
+static int xensock_create(struct net *net, struct socket *sock, int proto,
+ int kern, const struct proto_ops *xen_proto_ops)
+{
+ struct sock *sk;
+ int err = 0;
+
+ if (sock->type != SOCK_RAW)
+ return -ESOCKTNOSUPPORT;
+ if (proto != 0)
+ return -EPROTONOSUPPORT;
+
+ sk = xen_allocate_sock(net);
+ if (!sk)
+ return -ENOMEM;
+
+ sock->state = SS_UNCONNECTED;
+ sock->ops = xen_proto_ops;
+ sock_init_data(sock, sk);
+
+ sk->sk_destruct = xensock_destruct;
+ sk->sk_protocol = proto;
+
+ xen_sk(sk)->dev = NULL;
+
+ if (sk->sk_prot->init)
+ err = sk->sk_prot->init(sk);
+
+ if (err) {
+ /* release sk on errors */
+ sock_orphan(sk);
+ sock_put(sk);
+ }
+
+ return err;
+}
+
+static int xensock_server_create(struct net *net, struct socket *sock,
+ int proto, int kern)
+{
+ return xensock_create(net, sock, proto, kern, &xen_sock_server_ops);
+}
+
+static int xensock_client_create(struct net *net, struct socket *sock,
+ int proto, int kern)
+{
+ return xensock_create(net, sock, proto, kern, &xen_sock_client_ops);
+}
+
+static const struct net_proto_family xensock_server_family_ops = {
+ .family = PF_XENSOCK,
+ .create = xensock_server_create,
+ .owner = THIS_MODULE,
+};
+
+static const struct net_proto_family xensock_client_family_ops = {
+ .family = PF_XENSOCK,
+ .create = xensock_client_create,
+ .owner = THIS_MODULE,
+};
+
+static int xensock_proto_init(bool is_server_ops)
+{
+ int ret;
+
+ ret = proto_register(&xensock_proto, 0);
+ if (ret) {
+ pr_err("proto_register failed: %d\n", ret);
+ return ret;
+ }
+
+ if (is_server_ops)
+ ret = sock_register(&xensock_server_family_ops);
+ else
+ ret = sock_register(&xensock_client_family_ops);
+
+ if (ret) {
+ pr_err("sock_register failed: %d\n", ret);
+ goto proto_unreg;
+ }
+
+ return 0;
+
+proto_unreg:
+ proto_unregister(&xensock_proto);
+ return ret;
+}
+
+int xensock_proto_server_init(void)
+{
+ return xensock_proto_init(true);
+}
+EXPORT_SYMBOL(xensock_proto_server_init);
+
+int xensock_proto_client_init(void)
+{
+ return xensock_proto_init(false);
+}
+EXPORT_SYMBOL(xensock_proto_client_init);
+
+void xensock_proto_cleanup(void)
+{
+ xensock_unlink_all_dev_sk();
+ sock_unregister(PF_XENSOCK);
+ proto_unregister(&xensock_proto);
+}
+EXPORT_SYMBOL(xensock_proto_cleanup);
+
+MODULE_DESCRIPTION("xensock protocol");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_NETPROTO(AF_XENSOCK);
diff --git a/include/linux/socket.h b/include/linux/socket.h
index ec538fc..79ffa55 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -180,7 +180,8 @@ struct ucred {
#define AF_ALG 38 /* Algorithm sockets */
#define AF_NFC 39 /* NFC sockets */
#define AF_VSOCK 40 /* vSockets */
-#define AF_MAX 41 /* For now.. */
+#define AF_XENSOCK 41 /* xensock sockets */
+#define AF_MAX 42 /* For now.. */
/* Protocol families, same as address families. */
#define PF_UNSPEC AF_UNSPEC
@@ -225,6 +226,7 @@ struct ucred {
#define PF_ALG AF_ALG
#define PF_NFC AF_NFC
#define PF_VSOCK AF_VSOCK
+#define PF_XENSOCK AF_XENSOCK
#define PF_MAX AF_MAX
/* Maximum queue length specifiable by listen. */
diff --git a/include/net/af_xensock.h b/include/net/af_xensock.h
new file mode 100644
index 0000000..48df5ce
--- /dev/null
+++ b/include/net/af_xensock.h
@@ -0,0 +1,46 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef __AF_XENSOCK_H__
+#define __AF_XENSOCK_H__
+
+#include <net/xensock.h>
+
+struct xen_sock {
+ struct sock sk;
+ struct xen_sock_dev *dev;
+};
+
+static inline struct xen_sock *xen_sk(const struct sock *sk)
+{
+ return (struct xen_sock *)sk;
+}
+
+int xensock_proto_server_init(void);
+int xensock_proto_client_init(void);
+void xensock_proto_cleanup(void);
+
+#endif /* __AF_XENSOCK_H__ */
diff --git a/include/net/xensock.h b/include/net/xensock.h
new file mode 100644
index 0000000..2e5949b
--- /dev/null
+++ b/include/net/xensock.h
@@ -0,0 +1,130 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef __XENSOCK_H__
+#define __XENSOCK_H__
+
+#include <linux/bitops.h>
+#include <linux/if.h>
+#include <net/sock.h>
+
+#define XENSOCK_MTU 65535
+
+#define SOCKDEV_ALIGN 32
+
+#define __SOCK_STATE_NOCARRIER 0
+#define __SOCK_STATE_QUEUESTOPPED 1
+
+struct xen_sock_dev {
+ char name[IFNAMSIZ];
+ struct sock *sk;
+ spinlock_t lock; /* sock_dev operations lock */
+ unsigned long state;
+ unsigned short padded; /* Padding added by alloc_xen_sock_dev() */
+
+ int (*start_xmit)(struct sk_buff *skb, struct xen_sock_dev *dev);
+ unsigned long tx_queue_len;
+ struct list_head list;
+};
+
+/*
+ * xensock_dev_priv - access sock device private data
+ * @dev: xen_sock device
+ *
+ * Get xen_sock device private data
+ */
+static inline void *xensock_dev_priv(const struct xen_sock_dev *dev)
+{
+ return (char *)dev + ALIGN(sizeof(struct xen_sock_dev), SOCKDEV_ALIGN);
+}
+
+/*
+ * sockif_carrier_ok - test if carrier present
+ * @dev: xensock device
+ *
+ * Check if carrier is present on device
+ */
+static inline bool sockif_carrier_ok(const struct xen_sock_dev *dev)
+{
+ return !test_bit(__SOCK_STATE_NOCARRIER, &dev->state);
+}
+
+/*
+ * sockif_carrier_on - set carrier
+ * @dev: xensock device
+ */
+static inline void sockif_carrier_on(struct xen_sock_dev *dev)
+{
+ clear_bit(__SOCK_STATE_NOCARRIER, &dev->state);
+}
+
+/*
+ * sockif_carrier_on - clear carrier
+ * @dev: xensock device
+ */
+static inline void sockif_carrier_off(struct xen_sock_dev *dev)
+{
+ set_bit(__SOCK_STATE_NOCARRIER, &dev->state);
+}
+
+/*
+ * sockif_queue_stopped - test if tx queue is stopped
+ * @dev: xensock device
+ */
+static inline bool sockif_queue_stopped(const struct xen_sock_dev *dev)
+{
+ return test_bit(__SOCK_STATE_QUEUESTOPPED, &dev->state);
+}
+
+/*
+ * sockif_wake_queue - wake tx queue
+ * @dev: xensock device
+ */
+static inline void sockif_wake_queue(struct xen_sock_dev *dev)
+{
+ clear_bit(__SOCK_STATE_QUEUESTOPPED, &dev->state);
+}
+
+/*
+ * sockif_stop_queue - stop tx queue
+ * @dev: xensock device
+ */
+static inline void sockif_stop_queue(struct xen_sock_dev *dev)
+{
+ set_bit(__SOCK_STATE_QUEUESTOPPED, &dev->state);
+}
+
+struct xen_sock_dev *alloc_xen_sock_dev(int sizeof_priv, const char *name);
+void free_xen_sock_dev(struct xen_sock_dev *dev);
+int xensock_register_dev(struct xen_sock_dev *dev);
+void xensock_unregister_dev(struct xen_sock_dev *dev);
+void xensock_dev_unlink_sk(struct xen_sock_dev *dev);
+void xensock_unlink_all_dev_sk(void);
+int xensock_dev_wait(struct sock *sk, struct sock *nsk);
+int xensock_dev_send(struct sk_buff *skb, struct xen_sock_dev *dev);
+int xensock_dev_queue_rx_skb(struct sk_buff *skb, struct xen_sock_dev *dev);
+
+#endif /* __XENSOCK_H__ */
diff --git a/net/core/sock.c b/net/core/sock.c
index 026e01f..a57f264 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -262,7 +262,8 @@ static const char *const af_family_key_strings[AF_MAX+1] = {
"sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
"sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
"sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
- "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX"
+ "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_XENSOCK" ,
+ "sk_lock-AF_MAX"
};
static const char *const af_family_slock_key_strings[AF_MAX+1] = {
"slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
@@ -278,7 +279,8 @@ static const char *const af_family_slock_key_strings[AF_MAX+1] = {
"slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
"slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
"slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
- "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX"
+ "slock-AF_NFC" , "slock-AF_VSOCK" , "slock-AF_XENSOCK" ,
+ "slock-AF_MAX"
};
static const char *const af_family_clock_key_strings[AF_MAX+1] = {
"clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
@@ -294,7 +296,8 @@ static const char *const af_family_clock_key_strings[AF_MAX+1] = {
"clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
"clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
"clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
- "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX"
+ "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_XENSOCK" ,
+ "clock-AF_MAX"
};
/*
--
1.8.2.rc2
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 2/3] xen-sockback: add support of the xen-sockback driver
2014-08-08 11:32 [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers Oleksandr Dmytryshyn
2014-08-08 11:32 ` [PATCH 1/3] net: introduce new socket support: xensock Oleksandr Dmytryshyn
@ 2014-08-08 11:32 ` Oleksandr Dmytryshyn
2014-08-08 11:32 ` [PATCH 3/3] xen-sockfront: add support of the xen-sockfront driver Oleksandr Dmytryshyn
` (3 subsequent siblings)
5 siblings, 0 replies; 12+ messages in thread
From: Oleksandr Dmytryshyn @ 2014-08-08 11:32 UTC (permalink / raw)
To: Ian Campbell, Stefano Stabellini, Tim Deegan, xen-devel
This driver will allow to use xensock sockets for the
server application for the dom0/domD domain.
Signed-off-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>
---
drivers/net/Kconfig | 19 +
drivers/net/Makefile | 1 +
drivers/net/xen-sockback/Makefile | 3 +
drivers/net/xen-sockback/common.h | 150 ++++
drivers/net/xen-sockback/interface.c | 245 ++++++
drivers/net/xen-sockback/sockback.c | 1527 ++++++++++++++++++++++++++++++++++
drivers/net/xen-sockback/xenbus.c | 348 ++++++++
include/xen/interface/io/sockif.h | 74 ++
8 files changed, 2367 insertions(+)
create mode 100644 drivers/net/xen-sockback/Makefile
create mode 100644 drivers/net/xen-sockback/common.h
create mode 100644 drivers/net/xen-sockback/interface.c
create mode 100644 drivers/net/xen-sockback/sockback.c
create mode 100644 drivers/net/xen-sockback/xenbus.c
create mode 100644 include/xen/interface/io/sockif.h
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 420981a..e643f42 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -348,9 +348,28 @@ config XEN_NETDEV_BACKEND
compile this driver as a module, chose M here: the module
will be called xen-netback.
+config XEN_SOCKDEV_BACKEND
+ tristate "Xen backend socket device"
+ depends on XEN_BACKEND
+ select XEN_SOCKDEV_PROTO
+ help
+ This driver allows the kernel to act as a Xen socket driver
+ domain which exports paravirtual network devices to other
+ Xen domains. These devices can be accessed by any operating
+ system that implements a compatible front end.
+
+ The corresponding Linux frontend driver is enabled by the
+ CONFIG_XEN_SOCKDEV_FRONTEND configuration option.
+
+ If you are compiling a kernel to run in a Xen socket driver
+ domain (often this is domain 0) you should say Y here. To
+ compile this driver as a module, chose M here: the module
+ will be called xen-sockback.
+
config XEN_SOCKDEV_PROTO
bool
default n
+ depends on XEN_SOCKDEV_BACKEND
config VMXNET3
tristate "VMware VMXNET3 ethernet driver"
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 43bf910..96c6c97 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
obj-$(CONFIG_XEN_NETDEV_BACKEND) += xen-netback/
obj-$(CONFIG_XEN_SOCKDEV_PROTO) += xensock/
+obj-$(CONFIG_XEN_SOCKDEV_BACKEND) += xen-sockback/
obj-$(CONFIG_USB_CATC) += usb/
obj-$(CONFIG_USB_KAWETH) += usb/
diff --git a/drivers/net/xen-sockback/Makefile b/drivers/net/xen-sockback/Makefile
new file mode 100644
index 0000000..c255867
--- /dev/null
+++ b/drivers/net/xen-sockback/Makefile
@@ -0,0 +1,3 @@
+obj-$(CONFIG_XEN_SOCKDEV_BACKEND) := xen-sockback.o
+
+xen-sockback-y := sockback.o xenbus.o interface.o
diff --git a/drivers/net/xen-sockback/common.h b/drivers/net/xen-sockback/common.h
new file mode 100644
index 0000000..b5b09bb
--- /dev/null
+++ b/drivers/net/xen-sockback/common.h
@@ -0,0 +1,150 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef __XEN_SOCKBACK__COMMON_H__
+#define __XEN_SOCKBACK__COMMON_H__
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/ip.h>
+#include <linux/in.h>
+#include <linux/io.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+
+#include <xen/interface/io/sockif.h>
+#include <xen/interface/grant_table.h>
+#include <xen/grant_table.h>
+#include <xen/xenbus.h>
+
+#include <net/xensock.h>
+#include <net/af_xensock.h>
+
+struct xen_sockbk;
+
+struct xenvsock {
+ /* Unique identifier for this interface. */
+ domid_t domid;
+
+ /* Reference to xensock processing backend. */
+ struct xen_sockbk *sockbk;
+
+ /* Physical parameters of the comms window. */
+ unsigned int irq;
+
+ /* Back pointer to the xenbus_device. */
+ struct xenbus_device *xbdev;
+
+ /* List of frontends to notify after a batch of frames sent. */
+ struct list_head notify_list;
+
+ /* The shared rings and indexes. */
+ struct xen_sockif_tx_back_ring tx;
+ struct xen_sockif_rx_back_ring rx;
+
+ /* Internal feature information. */
+ u8 can_queue:1; /* can queue packets for receiver? */
+
+ /* Allow xenvsock_start_xmit() to peek ahead in the rx request
+ * ring. This is a prediction of what rx_req_cons will be
+ * once all queued skbs are put on the ring.
+ */
+ RING_IDX rx_req_cons_peek;
+
+ /* Transmit shaping: allow 'credit_bytes' every 'credit_usec'. */
+ unsigned long credit_bytes;
+ unsigned long credit_usec;
+ unsigned long remaining_credit;
+ struct timer_list credit_timeout;
+
+ /* Statistics */
+ unsigned long rx_gso_checksum_fixup;
+
+ /* Miscellaneous private stuff. */
+ struct list_head schedule_list;
+ atomic_t refcnt;
+ struct xen_sock_dev *dev;
+
+ wait_queue_head_t waiting_to_free;
+};
+
+#define XEN_SOCKIF_TX_RING_SIZE __CONST_RING_SIZE(xen_sockif_tx, PAGE_SIZE)
+#define XEN_SOCKIF_RX_RING_SIZE __CONST_RING_SIZE(xen_sockif_rx, PAGE_SIZE)
+
+struct xenvsock *xenvsock_alloc(struct device *parent,
+ domid_t domid,
+ unsigned int handle);
+
+int xenvsock_connect(struct xenvsock *vsock, unsigned long tx_ring_ref,
+ unsigned long rx_ring_ref, unsigned int evtchn);
+void xenvsock_disconnect(struct xenvsock *vsock);
+
+void xenvsock_get(struct xenvsock *vsock);
+void xenvsock_put(struct xenvsock *vsock);
+
+int xenvsock_xenbus_init(void);
+
+int xenvsock_schedulable(struct xenvsock *vsock);
+
+int xen_sockbk_rx_ring_full(struct xenvsock *vsock);
+
+int xen_sockbk_must_stop_queue(struct xenvsock *vsock);
+
+/* (Un)Map communication rings. */
+void xen_sockbk_unmap_frontend_rings(struct xenvsock *vsock);
+int xen_sockbk_map_frontend_rings(struct xenvsock *vsock,
+ grant_ref_t tx_ring_ref,
+ grant_ref_t rx_ring_ref);
+
+/* (De)Register a xenvsock with the xensock backend. */
+void xen_sockbk_add_xenvsock(struct xenvsock *vsock);
+void xen_sockbk_remove_xenvsock(struct xenvsock *vsock);
+
+/* (De)Schedule backend processing for a xenvsock */
+void xen_sockbk_schedule_xenvsock(struct xenvsock *vsock);
+void xen_sockbk_deschedule_xenvsock(struct xenvsock *vsock);
+
+/* Check for SKBs from frontend and schedule backend processing */
+void xen_sockbk_check_rx_xenvsock(struct xenvsock *vsock);
+/* Receive an SKB from the frontend */
+void xenvsock_receive_skb(struct xenvsock *vsock, struct sk_buff *skb);
+
+/* Queue an SKB for transmission to the frontend */
+void xen_sockbk_queue_tx_skb(struct xenvsock *vsock, struct sk_buff *skb);
+/* Notify xenvsock that ring now has space to send an skb to the frontend */
+void xenvsock_notify_tx_completion(struct xenvsock *vsock);
+
+/* Prevent the device from generating any further traffic. */
+void xenvsock_carrier_off(struct xenvsock *vsock);
+
+/* Returns number of ring slots required to send an skb to the frontend */
+unsigned int xen_sockbk_count_skb_slots(struct xenvsock *vsock,
+ struct sk_buff *skb);
+
+#endif /* __XEN_SOCKBACK__COMMON_H__ */
diff --git a/drivers/net/xen-sockback/interface.c b/drivers/net/xen-sockback/interface.c
new file mode 100644
index 0000000..995fb22
--- /dev/null
+++ b/drivers/net/xen-sockback/interface.c
@@ -0,0 +1,245 @@
+/*
+ * Xenvsock-device interface management.
+ *
+ * Copyright (c) 2004-2005, Keir Fraser
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "common.h"
+
+#include <xen/events.h>
+#include <asm/xen/hypercall.h>
+
+#define XENVSOCK_QUEUE_LENGTH 32
+
+void xenvsock_get(struct xenvsock *vsock)
+{
+ atomic_inc(&vsock->refcnt);
+}
+
+void xenvsock_put(struct xenvsock *vsock)
+{
+ if (atomic_dec_and_test(&vsock->refcnt))
+ wake_up(&vsock->waiting_to_free);
+}
+
+int xenvsock_schedulable(struct xenvsock *vsock)
+{
+ return sockif_carrier_ok(vsock->dev);
+}
+
+static int xenvsock_rx_schedulable(struct xenvsock *vsock)
+{
+ return xenvsock_schedulable(vsock) && !xen_sockbk_rx_ring_full(vsock);
+}
+
+static irqreturn_t xenvsock_interrupt(int irq, void *dev_id)
+{
+ struct xenvsock *vsock = dev_id;
+
+ if (vsock->sockbk == NULL)
+ return IRQ_NONE;
+
+ xen_sockbk_schedule_xenvsock(vsock);
+
+ if (xenvsock_rx_schedulable(vsock))
+ sockif_wake_queue(vsock->dev);
+
+ return IRQ_HANDLED;
+}
+
+static int xenvsock_start_xmit(struct sk_buff *skb, struct xen_sock_dev *dev)
+{
+ struct xenvsock *vsock = xensock_dev_priv(dev);
+
+ if (vsock->sockbk == NULL)
+ goto drop;
+
+ /* Drop the packet if the target domain has no receive buffers. */
+ if (!xenvsock_rx_schedulable(vsock))
+ goto drop;
+
+ skb->dev = (struct net_device *)dev;
+
+ /* Reserve ring slots for the worst-case number of fragments. */
+ vsock->rx_req_cons_peek += xen_sockbk_count_skb_slots(vsock, skb);
+ xenvsock_get(vsock);
+
+ if (vsock->can_queue && xen_sockbk_must_stop_queue(vsock))
+ sockif_stop_queue(dev);
+
+ xen_sockbk_queue_tx_skb(vsock, skb);
+
+ return 0;
+
+ drop:
+ dev_kfree_skb(skb);
+ return 0;
+}
+
+void xenvsock_receive_skb(struct xenvsock *vsock, struct sk_buff *skb)
+{
+ xensock_dev_queue_rx_skb(skb, vsock->dev);
+}
+
+void xenvsock_notify_tx_completion(struct xenvsock *vsock)
+{
+ if (sockif_queue_stopped(vsock->dev) && xenvsock_rx_schedulable(vsock))
+ sockif_wake_queue(vsock->dev);
+}
+
+static void xenvsock_up(struct xenvsock *vsock)
+{
+ xen_sockbk_add_xenvsock(vsock);
+ enable_irq(vsock->irq);
+ xen_sockbk_check_rx_xenvsock(vsock);
+}
+
+static void xenvsock_down(struct xenvsock *vsock)
+{
+ disable_irq(vsock->irq);
+ del_timer_sync(&vsock->credit_timeout);
+ xen_sockbk_deschedule_xenvsock(vsock);
+ xen_sockbk_remove_xenvsock(vsock);
+}
+
+static const struct xenvsock_stat {
+ char name[ETH_GSTRING_LEN];
+ u16 offset;
+} xenvsock_stats[] = {
+ {
+ "rx_gso_checksum_fixup",
+ offsetof(struct xenvsock, rx_gso_checksum_fixup)
+ },
+};
+
+struct xenvsock *xenvsock_alloc(struct device *parent, domid_t domid,
+ unsigned int handle)
+{
+ int err;
+ struct xen_sock_dev *dev;
+ struct xenvsock *vsock;
+ char name[IFNAMSIZ] = {};
+
+ snprintf(name, IFNAMSIZ - 1, "vsock%u.%u", domid, handle);
+ dev = alloc_xen_sock_dev(sizeof(struct xenvsock), name);
+ if (dev == NULL) {
+ pr_warn("Could not allocate sockdev\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ vsock = xensock_dev_priv(dev);
+ vsock->domid = domid;
+ vsock->sockbk = NULL;
+ atomic_set(&vsock->refcnt, 1);
+ init_waitqueue_head(&vsock->waiting_to_free);
+ vsock->dev = dev;
+ INIT_LIST_HEAD(&vsock->schedule_list);
+ INIT_LIST_HEAD(&vsock->notify_list);
+
+ vsock->credit_bytes = ~0UL;
+ vsock->remaining_credit = ~0UL;
+ vsock->credit_usec = 0UL;
+ init_timer(&vsock->credit_timeout);
+ /* Initialize 'expires' now: it's used to track the credit window. */
+ vsock->credit_timeout.expires = jiffies;
+
+ dev->start_xmit = xenvsock_start_xmit;
+
+ dev->tx_queue_len = XENVSOCK_QUEUE_LENGTH;
+
+ sockif_carrier_off(dev);
+
+ err = xensock_register_dev(dev);
+ if (err) {
+ pr_warn("Could not register device: err=%d\n", err);
+ free_xen_sock_dev(dev);
+ return ERR_PTR(err);
+ }
+
+ pr_warn("Successfully created xenvsock\n");
+ return vsock;
+}
+
+int xenvsock_connect(struct xenvsock *vsock, unsigned long tx_ring_ref,
+ unsigned long rx_ring_ref, unsigned int evtchn)
+{
+ int err = -ENOMEM;
+
+ /* Already connected through? */
+ if (vsock->irq)
+ return 0;
+
+ err = xen_sockbk_map_frontend_rings(vsock, tx_ring_ref, rx_ring_ref);
+ if (err < 0)
+ goto err;
+
+ err = bind_interdomain_evtchn_to_irqhandler(
+ vsock->domid, evtchn, xenvsock_interrupt, 0,
+ vsock->dev->name, vsock);
+ if (err < 0)
+ goto err_unmap;
+ vsock->irq = err;
+ disable_irq(vsock->irq);
+
+ xenvsock_get(vsock);
+
+ sockif_carrier_on(vsock->dev);
+ xenvsock_up(vsock);
+
+ return 0;
+err_unmap:
+ xen_sockbk_unmap_frontend_rings(vsock);
+err:
+ return err;
+}
+
+void xenvsock_carrier_off(struct xenvsock *vsock)
+{
+ struct xen_sock_dev *dev = vsock->dev;
+
+ sockif_carrier_off(dev); /* discard queued packets */
+ xenvsock_down(vsock);
+ xenvsock_put(vsock);
+}
+
+void xenvsock_disconnect(struct xenvsock *vsock)
+{
+ if (sockif_carrier_ok(vsock->dev))
+ xenvsock_carrier_off(vsock);
+
+ atomic_dec(&vsock->refcnt);
+ wait_event(vsock->waiting_to_free, atomic_read(&vsock->refcnt) == 0);
+
+ if (vsock->irq)
+ unbind_from_irqhandler(vsock->irq, vsock);
+
+ xensock_unregister_dev(vsock->dev);
+
+ xen_sockbk_unmap_frontend_rings(vsock);
+
+ free_xen_sock_dev(vsock->dev);
+}
diff --git a/drivers/net/xen-sockback/sockback.c b/drivers/net/xen-sockback/sockback.c
new file mode 100644
index 0000000..84f5848
--- /dev/null
+++ b/drivers/net/xen-sockback/sockback.c
@@ -0,0 +1,1527 @@
+/*
+ * Back-end of the driver for xensock devices. A
+ * reference front-end implementation can be found in:
+ * drivers/net/xen-sockfront.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "common.h"
+
+#include <linux/kthread.h>
+#include <linux/if_vlan.h>
+
+#include <net/tcp.h>
+
+#include <xen/xen.h>
+#include <xen/events.h>
+#include <xen/interface/memory.h>
+
+#include <asm/xen/hypercall.h>
+#include <asm/xen/page.h>
+
+struct pending_tx_info {
+ struct xen_sockif_tx_request req;
+ struct xenvsock *vsock;
+};
+typedef unsigned int pending_ring_idx_t;
+
+struct sockbk_rx_meta {
+ int id;
+ int size;
+};
+
+#define SOCK_DEV_SKB(skb) ((struct xen_sock_dev *)((skb)->dev))
+
+#define MAX_PENDING_REQS 256
+
+/* Discriminate from any valid pending_idx value. */
+#define INVALID_PENDING_IDX 0xFFFF
+
+#define MAX_BUFFER_OFFSET PAGE_SIZE
+
+/* extra field used in struct page */
+union page_ext {
+ struct {
+#if BITS_PER_LONG < 64
+#define IDX_WIDTH 8
+#define GROUP_WIDTH (BITS_PER_LONG - IDX_WIDTH)
+ unsigned int group:GROUP_WIDTH;
+ unsigned int idx:IDX_WIDTH;
+#else
+ unsigned int group, idx;
+#endif
+ } e;
+ void *mapping;
+};
+
+struct xen_sockbk {
+ wait_queue_head_t wq;
+ struct task_struct *task;
+
+ struct sk_buff_head rx_queue;
+ struct sk_buff_head tx_queue;
+
+ struct timer_list sock_timer;
+
+ struct page *mmap_pages[MAX_PENDING_REQS];
+
+ pending_ring_idx_t pending_prod;
+ pending_ring_idx_t pending_cons;
+ struct list_head sock_schedule_list;
+
+ /* Protect the sock_schedule_list in sockbk. */
+ spinlock_t sock_schedule_list_lock;
+
+ atomic_t sockfront_count;
+
+ struct pending_tx_info pending_tx_info[MAX_PENDING_REQS];
+ struct gnttab_copy tx_copy_ops[MAX_PENDING_REQS];
+
+ u16 pending_ring[MAX_PENDING_REQS];
+
+ /* Given MAX_BUFFER_OFFSET of 4096 the worst case is that each
+ * head/fragment page uses 2 copy operations because it
+ * straddles two buffers in the frontend.
+ */
+ struct gnttab_copy grant_copy_op[2*XEN_SOCKIF_RX_RING_SIZE];
+ struct sockbk_rx_meta meta[2*XEN_SOCKIF_RX_RING_SIZE];
+};
+
+static struct xen_sockbk *xen_sockbk;
+static int xen_sockbk_group_nr;
+
+void xen_sockbk_add_xenvsock(struct xenvsock *vsock)
+{
+ int i;
+ int min_sockfront_count;
+ int min_group = 0;
+ struct xen_sockbk *sockbk;
+
+ min_sockfront_count = atomic_read(&xen_sockbk[0].sockfront_count);
+ for (i = 0; i < xen_sockbk_group_nr; i++) {
+ int sockfront_count;
+
+ sockfront_count = atomic_read(&xen_sockbk[i].sockfront_count);
+ if (sockfront_count < min_sockfront_count) {
+ min_group = i;
+ min_sockfront_count = sockfront_count;
+ }
+ }
+
+ sockbk = &xen_sockbk[min_group];
+
+ vsock->sockbk = sockbk;
+ atomic_inc(&sockbk->sockfront_count);
+}
+
+void xen_sockbk_remove_xenvsock(struct xenvsock *vsock)
+{
+ struct xen_sockbk *sockbk = vsock->sockbk;
+
+ vsock->sockbk = NULL;
+ atomic_dec(&sockbk->sockfront_count);
+}
+
+static void xen_sockbk_idx_release(struct xen_sockbk *sockbk, u16 pending_idx,
+ u8 status);
+static void make_tx_response(struct xenvsock *vsock,
+ struct xen_sockif_tx_request *txp,
+ s8 st);
+static struct xen_sockif_rx_response *make_rx_response(struct xenvsock *vsock,
+ u16 id, s8 st,
+ u16 offset,
+ u16 size,
+ u16 flags);
+
+static inline unsigned long idx_to_pfn(struct xen_sockbk *sockbk,
+ u16 idx)
+{
+ return page_to_pfn(sockbk->mmap_pages[idx]);
+}
+
+static inline unsigned long idx_to_kaddr(struct xen_sockbk *sockbk,
+ u16 idx)
+{
+ return (unsigned long)pfn_to_kaddr(idx_to_pfn(sockbk, idx));
+}
+
+/* extra field used in struct page */
+static inline void set_page_ext(struct page *pg, struct xen_sockbk *sockbk,
+ unsigned int idx)
+{
+ unsigned int group = sockbk - xen_sockbk;
+ union page_ext ext = { .e = { .group = group + 1, .idx = idx } };
+
+ BUILD_BUG_ON(sizeof(ext) > sizeof(ext.mapping));
+ pg->mapping = ext.mapping;
+}
+
+static int get_page_ext(struct page *pg,
+ unsigned int *pgroup, unsigned int *pidx)
+{
+ union page_ext ext = { .mapping = pg->mapping };
+ struct xen_sockbk *sockbk;
+ unsigned int group, idx;
+
+ group = ext.e.group - 1;
+
+ if (group < 0 || group >= xen_sockbk_group_nr)
+ return 0;
+
+ sockbk = &xen_sockbk[group];
+
+ idx = ext.e.idx;
+
+ if ((idx < 0) || (idx >= MAX_PENDING_REQS))
+ return 0;
+
+ if (sockbk->mmap_pages[idx] != pg)
+ return 0;
+
+ *pgroup = group;
+ *pidx = idx;
+
+ return 1;
+}
+
+/* This is the amount of packet we copy rather than map, so that the
+ * guest can't fiddle with the contents of the headers while we do
+ * packet processing on them.
+ */
+#define PKT_PROT_LEN (ETH_HLEN + \
+ VLAN_HLEN + \
+ sizeof(struct iphdr) + MAX_IPOPTLEN + \
+ sizeof(struct tcphdr) + MAX_TCP_OPTION_SPACE)
+
+static u16 frag_get_pending_idx(skb_frag_t *frag)
+{
+ return (u16)frag->page_offset;
+}
+
+static void frag_set_pending_idx(skb_frag_t *frag, u16 pending_idx)
+{
+ frag->page_offset = pending_idx;
+}
+
+static inline pending_ring_idx_t pending_index(unsigned i)
+{
+ return i & (MAX_PENDING_REQS-1);
+}
+
+static inline pending_ring_idx_t nr_pending_reqs(struct xen_sockbk *sockbk)
+{
+ return MAX_PENDING_REQS -
+ sockbk->pending_prod + sockbk->pending_cons;
+}
+
+static void xen_sockbk_kick_thread(struct xen_sockbk *sockbk)
+{
+ wake_up(&sockbk->wq);
+}
+
+static int max_required_rx_slots(struct xenvsock *vsock)
+{
+ int max = DIV_ROUND_UP(XENSOCK_MTU, PAGE_SIZE);
+ return max;
+}
+
+int xen_sockbk_rx_ring_full(struct xenvsock *vsock)
+{
+ RING_IDX peek = vsock->rx_req_cons_peek;
+ RING_IDX needed = max_required_rx_slots(vsock);
+ RING_IDX rsp_prod = vsock->rx.rsp_prod_pvt + XEN_SOCKIF_RX_RING_SIZE;
+
+ return ((vsock->rx.sring->req_prod - peek) < needed) ||
+ ((rsp_prod - peek) < needed);
+}
+
+int xen_sockbk_must_stop_queue(struct xenvsock *vsock)
+{
+ if (!xen_sockbk_rx_ring_full(vsock))
+ return 0;
+
+ vsock->rx.sring->req_event = vsock->rx_req_cons_peek +
+ max_required_rx_slots(vsock);
+ mb(); /* request notification /then/ check the queue */
+
+ return xen_sockbk_rx_ring_full(vsock);
+}
+
+/* Returns true if we should start a new receive buffer instead of
+ * adding 'size' bytes to a buffer which currently contains 'offset'
+ * bytes.
+ */
+static bool start_new_rx_buffer(int offset, unsigned long size, int head)
+{
+ /* simple case: we have completely filled the current buffer. */
+ if (offset == MAX_BUFFER_OFFSET)
+ return true;
+
+ /* complex case: start a fresh buffer if the current frag
+ * would overflow the current buffer but only if:
+ * (i) this frag would fit completely in the next buffer
+ * and (ii) there is already some data in the current buffer
+ * and (iii) this is not the head buffer.
+ *
+ * Where:
+ * - (i) stops us splitting a frag into two copies
+ * unless the frag is too large for a single buffer.
+ * - (ii) stops us from leaving a buffer pointlessly empty.
+ * - (iii) stops us leaving the first buffer
+ * empty. Strictly speaking this is already covered
+ * by (ii) but is explicitly checked because
+ * sock front relies on the first buffer being
+ * non-empty and can crash otherwise.
+ *
+ * This means we will effectively linearise small
+ * frags but do not needlessly split large buffers
+ * into multiple copies tend to give large frags their
+ * own buffers as before.
+ */
+ if ((offset + size > MAX_BUFFER_OFFSET) &&
+ (size <= MAX_BUFFER_OFFSET) && offset && !head)
+ return true;
+
+ return false;
+}
+
+/* Figure out how many ring slots we're going to need to send @skb to
+ * the guest. This function is essentially a dry run of
+ * sockbk_gop_frag_copy.
+ */
+unsigned int xen_sockbk_count_skb_slots(struct xenvsock *vsock,
+ struct sk_buff *skb)
+{
+ unsigned int count;
+ int i, copy_off;
+
+ count = DIV_ROUND_UP(skb_headlen(skb), PAGE_SIZE);
+
+ copy_off = skb_headlen(skb) % PAGE_SIZE;
+
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
+ unsigned long offset = skb_shinfo(skb)->frags[i].page_offset;
+ unsigned long bytes;
+
+ offset &= ~PAGE_MASK;
+
+ while (size > 0) {
+ BUG_ON(offset >= PAGE_SIZE);
+ BUG_ON(copy_off > MAX_BUFFER_OFFSET);
+
+ bytes = PAGE_SIZE - offset;
+
+ if (bytes > size)
+ bytes = size;
+
+ if (start_new_rx_buffer(copy_off, bytes, 0)) {
+ count++;
+ copy_off = 0;
+ }
+
+ if (copy_off + bytes > MAX_BUFFER_OFFSET)
+ bytes = MAX_BUFFER_OFFSET - copy_off;
+
+ copy_off += bytes;
+
+ offset += bytes;
+ size -= bytes;
+
+ if (offset == PAGE_SIZE)
+ offset = 0;
+ }
+ }
+ return count;
+}
+
+struct sockrx_pending_operations {
+ unsigned copy_prod, copy_cons;
+ unsigned meta_prod, meta_cons;
+ struct gnttab_copy *copy;
+ struct sockbk_rx_meta *meta;
+ int copy_off;
+ grant_ref_t copy_gref;
+};
+
+static
+struct sockbk_rx_meta *get_next_rx_buf(struct xenvsock *vsock,
+ struct sockrx_pending_operations *spo)
+{
+ struct sockbk_rx_meta *meta;
+ struct xen_sockif_rx_request *req;
+
+ req = RING_GET_REQUEST(&vsock->rx, vsock->rx.req_cons++);
+
+ meta = spo->meta + spo->meta_prod++;
+ meta->size = 0;
+ meta->id = req->id;
+
+ spo->copy_off = 0;
+ spo->copy_gref = req->gref;
+
+ return meta;
+}
+
+/* Set up the grant operations for this fragment. If it's a flipping
+ * interface, we also set up the unmap request from here.
+ */
+static void sockbk_gop_frag_copy(struct xenvsock *vsock, struct sk_buff *skb,
+ struct sockrx_pending_operations *spo,
+ struct page *page, unsigned long size,
+ unsigned long offset, int *head)
+{
+ struct gnttab_copy *copy_gop;
+ struct sockbk_rx_meta *meta;
+ /* These variables are used iff get_page_ext returns true,
+ * in which case they are guaranteed to be initialized.
+ */
+ unsigned int uninitialized_var(group), uninitialized_var(idx);
+ int foreign = get_page_ext(page, &group, &idx);
+ unsigned long bytes;
+
+ /* Data must not cross a page boundary. */
+ BUG_ON(size + offset > PAGE_SIZE<<compound_order(page));
+
+ meta = spo->meta + spo->meta_prod - 1;
+
+ /* Skip unused frames from start of page */
+ page += offset >> PAGE_SHIFT;
+ offset &= ~PAGE_MASK;
+
+ while (size > 0) {
+ BUG_ON(offset >= PAGE_SIZE);
+ BUG_ON(spo->copy_off > MAX_BUFFER_OFFSET);
+
+ bytes = PAGE_SIZE - offset;
+
+ if (bytes > size)
+ bytes = size;
+
+ if (start_new_rx_buffer(spo->copy_off, bytes, *head)) {
+ /* Sockfront requires there to be some data in the head
+ * buffer.
+ */
+ BUG_ON(*head);
+
+ meta = get_next_rx_buf(vsock, spo);
+ }
+
+ if (spo->copy_off + bytes > MAX_BUFFER_OFFSET)
+ bytes = MAX_BUFFER_OFFSET - spo->copy_off;
+
+ copy_gop = spo->copy + spo->copy_prod++;
+ copy_gop->flags = GNTCOPY_dest_gref;
+ if (foreign) {
+ struct xen_sockbk *sockbk = &xen_sockbk[group];
+ struct pending_tx_info *src_pend;
+
+ src_pend = &sockbk->pending_tx_info[idx];
+
+ copy_gop->source.domid = src_pend->vsock->domid;
+ copy_gop->source.u.ref = src_pend->req.gref;
+ copy_gop->flags |= GNTCOPY_source_gref;
+ } else {
+ void *vaddr = page_address(page);
+
+ copy_gop->source.domid = DOMID_SELF;
+ copy_gop->source.u.gmfn = virt_to_mfn(vaddr);
+ }
+ copy_gop->source.offset = offset;
+ copy_gop->dest.domid = vsock->domid;
+
+ copy_gop->dest.offset = spo->copy_off;
+ copy_gop->dest.u.ref = spo->copy_gref;
+ copy_gop->len = bytes;
+
+ spo->copy_off += bytes;
+ meta->size += bytes;
+
+ offset += bytes;
+ size -= bytes;
+
+ /* Next frame */
+ if (offset == PAGE_SIZE && size) {
+ BUG_ON(!PageCompound(page));
+ page++;
+ offset = 0;
+ }
+
+ *head = 0; /* There must be something in this buffer now. */
+ }
+}
+
+/* Prepare an SKB to be transmitted to the frontend.
+ *
+ * This function is responsible for allocating grant operations, meta
+ * structures, etc.
+ *
+ * It returns the number of meta structures consumed. The number of
+ * ring slots used is always equal to the number of meta slots used
+ * plus the number of GSO descriptors used. Currently, we use either
+ * zero GSO descriptors (for non-GSO packets) or one descriptor (for
+ * frontend-side LRO).
+ */
+static int sockbk_gop_skb(struct sk_buff *skb,
+ struct sockrx_pending_operations *spo)
+{
+ struct xenvsock *vsock = xensock_dev_priv(SOCK_DEV_SKB(skb));
+ int nr_frags = skb_shinfo(skb)->nr_frags;
+ int i;
+ struct xen_sockif_rx_request *req;
+ struct sockbk_rx_meta *meta;
+ unsigned char *data;
+ int head = 1;
+ int old_meta_prod;
+
+ old_meta_prod = spo->meta_prod;
+
+ req = RING_GET_REQUEST(&vsock->rx, vsock->rx.req_cons++);
+ meta = spo->meta + spo->meta_prod++;
+
+ meta->size = 0;
+ meta->id = req->id;
+ spo->copy_off = 0;
+ spo->copy_gref = req->gref;
+
+ data = skb->data;
+ while (data < skb_tail_pointer(skb)) {
+ unsigned int offset = offset_in_page(data);
+ unsigned int len = PAGE_SIZE - offset;
+
+ if (data + len > skb_tail_pointer(skb))
+ len = skb_tail_pointer(skb) - data;
+
+ sockbk_gop_frag_copy(vsock, skb, spo,
+ virt_to_page(data), len, offset, &head);
+ data += len;
+ }
+
+ for (i = 0; i < nr_frags; i++) {
+ sockbk_gop_frag_copy(vsock, skb, spo,
+ skb_frag_page(&skb_shinfo(skb)->frags[i]),
+ skb_frag_size(&skb_shinfo(skb)->frags[i]),
+ skb_shinfo(skb)->frags[i].page_offset,
+ &head);
+ }
+
+ return spo->meta_prod - old_meta_prod;
+}
+
+/* This is a twin to sockbk_gop_skb. Assume that sockbk_gop_skb was
+ * used to set up the operations on the top of
+ * sockrx_pending_operations, which have since been done. Check that
+ * they didn't give any errors and advance over them.
+ */
+static int sockbk_check_gop(struct xenvsock *vsock, int nr_meta_slots,
+ struct sockrx_pending_operations *spo)
+{
+ struct gnttab_copy *copy_op;
+ int status = XEN_SOCKIF_RSP_OKAY;
+ int i;
+
+ for (i = 0; i < nr_meta_slots; i++) {
+ copy_op = spo->copy + spo->copy_cons++;
+ if (copy_op->status != GNTST_okay) {
+ dev_dbg(&vsock->xbdev->dev,
+ "Bad status %d from copy to DOM%d.\n",
+ copy_op->status, vsock->domid);
+ status = XEN_SOCKIF_RSP_ERROR;
+ }
+ }
+
+ return status;
+}
+
+static void sockbk_add_frag_responses(struct xenvsock *vsock, int status,
+ struct sockbk_rx_meta *meta,
+ int nr_meta_slots)
+{
+ int i;
+ unsigned long offset;
+
+ /* No fragments used */
+ if (nr_meta_slots <= 1)
+ return;
+
+ nr_meta_slots--;
+
+ for (i = 0; i < nr_meta_slots; i++) {
+ int flags;
+
+ if (i == nr_meta_slots - 1)
+ flags = 0;
+ else
+ flags = XEN_SOCKRXF_more_data;
+
+ offset = 0;
+ make_rx_response(vsock, meta[i].id, status, offset,
+ meta[i].size, flags);
+ }
+}
+
+struct skb_cb_overlay {
+ int meta_slots_used;
+};
+
+static void xen_sockbk_rx_action(struct xen_sockbk *sockbk)
+{
+ struct xenvsock *vsock = NULL, *tmp;
+ s8 status;
+ u16 irq, flags;
+ struct xen_sockif_rx_response *resp;
+ struct sk_buff_head rxq;
+ struct sk_buff *skb;
+ LIST_HEAD(notify);
+ int ret;
+ int nr_frags;
+ int count;
+ unsigned long offset;
+ struct skb_cb_overlay *sco;
+
+ struct sockrx_pending_operations spo = {
+ .copy = sockbk->grant_copy_op,
+ .meta = sockbk->meta,
+ };
+
+ skb_queue_head_init(&rxq);
+
+ count = 0;
+
+ while ((skb = skb_dequeue(&sockbk->rx_queue)) != NULL) {
+ vsock = xensock_dev_priv(SOCK_DEV_SKB(skb));
+
+ nr_frags = skb_shinfo(skb)->nr_frags;
+
+ sco = (struct skb_cb_overlay *)skb->cb;
+ sco->meta_slots_used = sockbk_gop_skb(skb, &spo);
+
+ count += nr_frags + 1;
+
+ __skb_queue_tail(&rxq, skb);
+
+ /* Filled the batch queue? */
+ if (count + MAX_SKB_FRAGS >= XEN_SOCKIF_RX_RING_SIZE)
+ break;
+ }
+
+ BUG_ON(spo.meta_prod > ARRAY_SIZE(sockbk->meta));
+
+ if (!spo.copy_prod)
+ return;
+
+ BUG_ON(spo.copy_prod > ARRAY_SIZE(sockbk->grant_copy_op));
+ gnttab_batch_copy(sockbk->grant_copy_op, spo.copy_prod);
+
+ while ((skb = __skb_dequeue(&rxq)) != NULL) {
+ sco = (struct skb_cb_overlay *)skb->cb;
+
+ vsock = xensock_dev_priv(SOCK_DEV_SKB(skb));
+
+ status = sockbk_check_gop(vsock, sco->meta_slots_used, &spo);
+
+ if (sco->meta_slots_used == 1)
+ flags = 0;
+ else
+ flags = XEN_SOCKRXF_more_data;
+
+ offset = 0;
+ resp = make_rx_response(vsock, sockbk->meta[spo.meta_cons].id,
+ status, offset,
+ sockbk->meta[spo.meta_cons].size,
+ flags);
+
+ sockbk_add_frag_responses(vsock, status,
+ sockbk->meta + spo.meta_cons + 1,
+ sco->meta_slots_used);
+
+ RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vsock->rx, ret);
+ irq = vsock->irq;
+ if (ret && list_empty(&vsock->notify_list))
+ list_add_tail(&vsock->notify_list, ¬ify);
+
+ xenvsock_notify_tx_completion(vsock);
+
+ xenvsock_put(vsock);
+ spo.meta_cons += sco->meta_slots_used;
+ dev_kfree_skb(skb);
+ }
+
+ list_for_each_entry_safe(vsock, tmp, ¬ify, notify_list) {
+ notify_remote_via_irq(vsock->irq);
+ list_del_init(&vsock->notify_list);
+ }
+
+ /* More work to do? */
+ if (!skb_queue_empty(&sockbk->rx_queue) &&
+ !timer_pending(&sockbk->sock_timer))
+ xen_sockbk_kick_thread(sockbk);
+}
+
+void xen_sockbk_queue_tx_skb(struct xenvsock *vsock, struct sk_buff *skb)
+{
+ struct xen_sockbk *sockbk = vsock->sockbk;
+
+ skb_queue_tail(&sockbk->rx_queue, skb);
+ xen_sockbk_kick_thread(sockbk);
+}
+
+static void xen_sockbk_alarm(unsigned long data)
+{
+ struct xen_sockbk *sockbk = (struct xen_sockbk *)data;
+
+ xen_sockbk_kick_thread(sockbk);
+}
+
+static int __on_sock_schedule_list(struct xenvsock *vsock)
+{
+ return !list_empty(&vsock->schedule_list);
+}
+
+/* Must be called with sock_schedule_list_lock held */
+static void remove_from_sock_schedule_list(struct xenvsock *vsock)
+{
+ if (likely(__on_sock_schedule_list(vsock))) {
+ list_del_init(&vsock->schedule_list);
+ xenvsock_put(vsock);
+ }
+}
+
+static struct xenvsock *poll_sock_schedule_list(struct xen_sockbk *sockbk)
+{
+ struct xenvsock *vsock = NULL;
+
+ spin_lock_irq(&sockbk->sock_schedule_list_lock);
+ if (list_empty(&sockbk->sock_schedule_list))
+ goto out;
+
+ vsock = list_first_entry(&sockbk->sock_schedule_list,
+ struct xenvsock, schedule_list);
+ if (!vsock)
+ goto out;
+
+ xenvsock_get(vsock);
+
+ remove_from_sock_schedule_list(vsock);
+out:
+ spin_unlock_irq(&sockbk->sock_schedule_list_lock);
+ return vsock;
+}
+
+void xen_sockbk_schedule_xenvsock(struct xenvsock *vsock)
+{
+ unsigned long flags;
+ struct xen_sockbk *sockbk = vsock->sockbk;
+ struct list_head *sockbk_schedule_list = &sockbk->sock_schedule_list;
+
+ if (__on_sock_schedule_list(vsock))
+ goto kick;
+
+ spin_lock_irqsave(&sockbk->sock_schedule_list_lock, flags);
+ if (!__on_sock_schedule_list(vsock) &&
+ likely(xenvsock_schedulable(vsock))) {
+ list_add_tail(&vsock->schedule_list, sockbk_schedule_list);
+ xenvsock_get(vsock);
+ }
+ spin_unlock_irqrestore(&sockbk->sock_schedule_list_lock, flags);
+
+kick:
+ smp_mb(); /* Ensure that an item is added to the shedule list */
+ if ((nr_pending_reqs(sockbk) < (MAX_PENDING_REQS/2)) &&
+ !list_empty(sockbk_schedule_list))
+ xen_sockbk_kick_thread(sockbk);
+}
+
+void xen_sockbk_deschedule_xenvsock(struct xenvsock *vsock)
+{
+ struct xen_sockbk *sockbk = vsock->sockbk;
+
+ spin_lock_irq(&sockbk->sock_schedule_list_lock);
+ remove_from_sock_schedule_list(vsock);
+ spin_unlock_irq(&sockbk->sock_schedule_list_lock);
+}
+
+void xen_sockbk_check_rx_xenvsock(struct xenvsock *vsock)
+{
+ int more_to_do;
+
+ RING_FINAL_CHECK_FOR_REQUESTS(&vsock->tx, more_to_do);
+
+ if (more_to_do)
+ xen_sockbk_schedule_xenvsock(vsock);
+}
+
+static void tx_add_credit(struct xenvsock *vsock)
+{
+ unsigned long max_burst, max_credit;
+
+ /* Allow a burst big enough to transmit a jumbo packet of up to 128kB.
+ * Otherwise the interface can seize up due to insufficient credit.
+ */
+ max_burst = RING_GET_REQUEST(&vsock->tx, vsock->tx.req_cons)->size;
+ max_burst = min(max_burst, 131072UL);
+ max_burst = max(max_burst, vsock->credit_bytes);
+
+ /* Take care that adding a new chunk of credit doesn't wrap to zero. */
+ max_credit = vsock->remaining_credit + vsock->credit_bytes;
+ if (max_credit < vsock->remaining_credit)
+ max_credit = ULONG_MAX; /* wrapped: clamp to ULONG_MAX */
+
+ vsock->remaining_credit = min(max_credit, max_burst);
+}
+
+static void tx_credit_callback(unsigned long data)
+{
+ struct xenvsock *vsock = (struct xenvsock *)data;
+
+ tx_add_credit(vsock);
+ xen_sockbk_check_rx_xenvsock(vsock);
+}
+
+static void sockbk_tx_err(struct xenvsock *vsock,
+ struct xen_sockif_tx_request *txp, RING_IDX end)
+{
+ RING_IDX cons = vsock->tx.req_cons;
+
+ do {
+ make_tx_response(vsock, txp, XEN_SOCKIF_RSP_ERROR);
+ if (cons == end)
+ break;
+ txp = RING_GET_REQUEST(&vsock->tx, cons++);
+ } while (1);
+ vsock->tx.req_cons = cons;
+ xen_sockbk_check_rx_xenvsock(vsock);
+ xenvsock_put(vsock);
+}
+
+static void sockbk_fatal_tx_err(struct xenvsock *vsock)
+{
+ dev_err(&vsock->xbdev->dev, "fatal error; disabling device\n");
+ xenvsock_carrier_off(vsock);
+ xenvsock_put(vsock);
+}
+
+static int sockbk_count_requests(struct xenvsock *vsock,
+ struct xen_sockif_tx_request *first,
+ struct xen_sockif_tx_request *txp,
+ int work_to_do)
+{
+ RING_IDX cons = vsock->tx.req_cons;
+ int frags = 0;
+
+ if (!(first->flags & XEN_SOCKTXF_more_data))
+ return 0;
+
+ do {
+ if (frags >= work_to_do) {
+ dev_err(&vsock->xbdev->dev, "Need more frags\n");
+ sockbk_fatal_tx_err(vsock);
+ return -ENODATA;
+ }
+
+ if (unlikely(frags >= MAX_SKB_FRAGS)) {
+ dev_err(&vsock->xbdev->dev, "Too many frags\n");
+ sockbk_fatal_tx_err(vsock);
+ return -E2BIG;
+ }
+
+ memcpy(txp, RING_GET_REQUEST(&vsock->tx, cons + frags),
+ sizeof(*txp));
+ if (txp->size > first->size) {
+ dev_err(&vsock->xbdev->dev, "Frag is bigger than frame.\n");
+ sockbk_fatal_tx_err(vsock);
+ return -EIO;
+ }
+
+ first->size -= txp->size;
+ frags++;
+
+ if (unlikely((txp->offset + txp->size) > PAGE_SIZE)) {
+ dev_err(&vsock->xbdev->dev, "txp->offset: %x, size: %u\n",
+ txp->offset, txp->size);
+ sockbk_fatal_tx_err(vsock);
+ return -EINVAL;
+ }
+ } while ((txp++)->flags & XEN_SOCKTXF_more_data);
+ return frags;
+}
+
+static struct page *xen_sockbk_alloc_page(struct xen_sockbk *sockbk,
+ struct sk_buff *skb,
+ u16 pending_idx)
+{
+ struct page *page;
+
+ page = alloc_page(GFP_KERNEL|__GFP_COLD);
+ if (!page)
+ return NULL;
+ set_page_ext(page, sockbk, pending_idx);
+ sockbk->mmap_pages[pending_idx] = page;
+ return page;
+}
+
+static
+struct gnttab_copy *xen_sockbk_get_requests(struct xen_sockbk *sockbk,
+ struct xenvsock *vsock,
+ struct sk_buff *skb,
+ struct xen_sockif_tx_request *txp,
+ struct gnttab_copy *gop)
+{
+ struct skb_shared_info *shinfo = skb_shinfo(skb);
+ skb_frag_t *frags = shinfo->frags;
+ u16 pending_idx = *((u16 *)skb->data);
+ int i, start;
+
+ /* Skip first skb fragment if it is on same page as header fragment. */
+ start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
+
+ for (i = start; i < shinfo->nr_frags; i++, txp++) {
+ struct page *page;
+ pending_ring_idx_t index;
+ struct pending_tx_info *pending_tx_info =
+ sockbk->pending_tx_info;
+
+ index = pending_index(sockbk->pending_cons++);
+ pending_idx = sockbk->pending_ring[index];
+ page = xen_sockbk_alloc_page(sockbk, skb, pending_idx);
+ if (!page)
+ goto err;
+
+ gop->source.u.ref = txp->gref;
+ gop->source.domid = vsock->domid;
+ gop->source.offset = txp->offset;
+
+ gop->dest.u.gmfn = virt_to_mfn(page_address(page));
+ gop->dest.domid = DOMID_SELF;
+ gop->dest.offset = txp->offset;
+
+ gop->len = txp->size;
+ gop->flags = GNTCOPY_source_gref;
+
+ gop++;
+
+ memcpy(&pending_tx_info[pending_idx].req, txp, sizeof(*txp));
+ xenvsock_get(vsock);
+ pending_tx_info[pending_idx].vsock = vsock;
+ frag_set_pending_idx(&frags[i], pending_idx);
+ }
+
+ return gop;
+err:
+ /* Unwind, freeing all pages and sending error responses. */
+ while (i-- > start) {
+ xen_sockbk_idx_release(sockbk, frag_get_pending_idx(&frags[i]),
+ XEN_SOCKIF_RSP_ERROR);
+ }
+ /* The head too, if necessary. */
+ if (start)
+ xen_sockbk_idx_release(sockbk, pending_idx,
+ XEN_SOCKIF_RSP_ERROR);
+
+ return NULL;
+}
+
+static int xen_sockbk_tx_check_gop(struct xen_sockbk *sockbk,
+ struct sk_buff *skb,
+ struct gnttab_copy **gopp)
+{
+ struct gnttab_copy *gop = *gopp;
+ u16 pending_idx = *((u16 *)skb->data);
+ struct skb_shared_info *shinfo = skb_shinfo(skb);
+ int nr_frags = shinfo->nr_frags;
+ int i, err, start;
+
+ /* Check status of header. */
+ err = gop->status;
+ if (unlikely(err))
+ xen_sockbk_idx_release(sockbk, pending_idx,
+ XEN_SOCKIF_RSP_ERROR);
+
+ /* Skip first skb fragment if it is on same page as header fragment. */
+ start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
+
+ for (i = start; i < nr_frags; i++) {
+ int j, newerr;
+
+ pending_idx = frag_get_pending_idx(&shinfo->frags[i]);
+
+ /* Check error status: if okay then remember grant handle. */
+ newerr = (++gop)->status;
+ if (likely(!newerr)) {
+ /* Had a previous error? Invalidate this fragment. */
+ if (unlikely(err))
+ xen_sockbk_idx_release(sockbk, pending_idx,
+ XEN_SOCKIF_RSP_OKAY);
+ continue;
+ }
+
+ /* Error on this fragment: respond to client with an error. */
+ xen_sockbk_idx_release(sockbk, pending_idx,
+ XEN_SOCKIF_RSP_ERROR);
+
+ /* Not the first error? Preceding frags already invalidated. */
+ if (err)
+ continue;
+
+ /* First error: invalidate header and preceding fragments. */
+ pending_idx = *((u16 *)skb->data);
+ xen_sockbk_idx_release(sockbk, pending_idx,
+ XEN_SOCKIF_RSP_OKAY);
+ for (j = start; j < i; j++) {
+ pending_idx = frag_get_pending_idx(&shinfo->frags[j]);
+ xen_sockbk_idx_release(sockbk, pending_idx,
+ XEN_SOCKIF_RSP_OKAY);
+ }
+
+ /* Remember the error: invalidate all subsequent fragments. */
+ err = newerr;
+ }
+
+ *gopp = gop + 1;
+ return err;
+}
+
+static void xen_sockbk_fill_frags(struct xen_sockbk *sockbk,
+ struct sk_buff *skb)
+{
+ struct skb_shared_info *shinfo = skb_shinfo(skb);
+ int nr_frags = shinfo->nr_frags;
+ int i;
+
+ for (i = 0; i < nr_frags; i++) {
+ skb_frag_t *frag = shinfo->frags + i;
+ struct xen_sockif_tx_request *txp;
+ struct page *page;
+ u16 pending_idx;
+
+ pending_idx = frag_get_pending_idx(frag);
+
+ txp = &sockbk->pending_tx_info[pending_idx].req;
+ page = virt_to_page(idx_to_kaddr(sockbk, pending_idx));
+ __skb_fill_page_desc(skb, i, page, txp->offset, txp->size);
+ skb->len += txp->size;
+ skb->data_len += txp->size;
+ skb->truesize += txp->size;
+
+ /* Take an extra reference to offset xen_sockbk_idx_release */
+ get_page(sockbk->mmap_pages[pending_idx]);
+ xen_sockbk_idx_release(sockbk, pending_idx,
+ XEN_SOCKIF_RSP_OKAY);
+ }
+}
+
+static bool tx_credit_exceeded(struct xenvsock *vsock, unsigned size)
+{
+ unsigned long now = jiffies;
+ unsigned long next_credit =
+ vsock->credit_timeout.expires +
+ msecs_to_jiffies(vsock->credit_usec / 1000);
+
+ /* Timer could already be pending in rare cases. */
+ if (timer_pending(&vsock->credit_timeout))
+ return true;
+
+ /* Passed the point where we can replenish credit? */
+ if (time_after_eq(now, next_credit)) {
+ vsock->credit_timeout.expires = now;
+ tx_add_credit(vsock);
+ }
+
+ /* Still too big to send right now? Set a callback. */
+ if (size > vsock->remaining_credit) {
+ vsock->credit_timeout.data =
+ (unsigned long)vsock;
+ vsock->credit_timeout.function =
+ tx_credit_callback;
+ mod_timer(&vsock->credit_timeout,
+ next_credit);
+
+ return true;
+ }
+
+ return false;
+}
+
+static unsigned xen_sockbk_tx_build_gops(struct xen_sockbk *sockbk)
+{
+ struct gnttab_copy *gop = sockbk->tx_copy_ops, *request_gop;
+ struct sk_buff *skb;
+ int ret;
+
+ while (((nr_pending_reqs(sockbk) + MAX_SKB_FRAGS) < MAX_PENDING_REQS) &&
+ !list_empty(&sockbk->sock_schedule_list)) {
+ struct xenvsock *vsock;
+ struct xen_sockif_tx_request txreq;
+ struct xen_sockif_tx_request txfrags[MAX_SKB_FRAGS];
+ struct page *page;
+ u16 pending_idx;
+ RING_IDX idx;
+ int work_to_do;
+ unsigned int data_len;
+ pending_ring_idx_t index;
+
+ /* Get a vsock from the list with work to do. */
+ vsock = poll_sock_schedule_list(sockbk);
+ /* This can sometimes happen because the test of
+ * list_empty(sock_schedule_list) at the top of the
+ * loop is unlocked. Just go back and have another
+ * look.
+ */
+ if (!vsock)
+ continue;
+
+ if (vsock->tx.sring->req_prod - vsock->tx.req_cons >
+ XEN_SOCKIF_TX_RING_SIZE) {
+ dev_err(&vsock->xbdev->dev,
+ "Impossible number of requests. "
+ "req_prod %d, req_cons %d, size %ld\n",
+ vsock->tx.sring->req_prod,
+ vsock->tx.req_cons,
+ XEN_SOCKIF_TX_RING_SIZE);
+ sockbk_fatal_tx_err(vsock);
+ continue;
+ }
+
+ RING_FINAL_CHECK_FOR_REQUESTS(&vsock->tx, work_to_do);
+ if (!work_to_do) {
+ xenvsock_put(vsock);
+ continue;
+ }
+
+ idx = vsock->tx.req_cons;
+ rmb(); /* Ensure that we see the request before we copy it. */
+ memcpy(&txreq, RING_GET_REQUEST(&vsock->tx, idx),
+ sizeof(txreq));
+
+ /* Credit-based scheduling. */
+ if (txreq.size > vsock->remaining_credit &&
+ tx_credit_exceeded(vsock, txreq.size)) {
+ xenvsock_put(vsock);
+ continue;
+ }
+
+ vsock->remaining_credit -= txreq.size;
+
+ work_to_do--;
+ vsock->tx.req_cons = ++idx;
+
+ ret = sockbk_count_requests(vsock, &txreq, txfrags, work_to_do);
+ if (unlikely(ret < 0))
+ continue;
+
+ idx += ret;
+
+ if (unlikely(txreq.size == 0)) {
+ dev_dbg(&vsock->xbdev->dev,
+ "Bad packet size: %d\n", txreq.size);
+ sockbk_tx_err(vsock, &txreq, idx);
+ continue;
+ }
+
+ /* No crossing a page as the payload mustn't fragment. */
+ if (unlikely((txreq.offset + txreq.size) > PAGE_SIZE)) {
+ dev_err(&vsock->xbdev->dev,
+ "txreq.offset: %x, size: %u, end: %lu\n",
+ txreq.offset, txreq.size,
+ (txreq.offset&~PAGE_MASK) + txreq.size);
+ sockbk_fatal_tx_err(vsock);
+ continue;
+ }
+
+ index = pending_index(sockbk->pending_cons);
+ pending_idx = sockbk->pending_ring[index];
+
+ data_len = (txreq.size > PKT_PROT_LEN &&
+ ret < MAX_SKB_FRAGS) ?
+ PKT_PROT_LEN : txreq.size;
+
+ skb = alloc_skb(data_len + NET_SKB_PAD + NET_IP_ALIGN,
+ GFP_ATOMIC | __GFP_NOWARN);
+ if (unlikely(skb == NULL)) {
+ dev_dbg(&vsock->xbdev->dev,
+ "Can't allocate a skb in start_xmit.\n");
+ sockbk_tx_err(vsock, &txreq, idx);
+ break;
+ }
+
+ /* Packets passed to sockif_rx() must have some headroom. */
+ skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
+
+ /* XXX could copy straight to head */
+ page = xen_sockbk_alloc_page(sockbk, skb, pending_idx);
+ if (!page) {
+ kfree_skb(skb);
+ sockbk_tx_err(vsock, &txreq, idx);
+ continue;
+ }
+
+ gop->source.u.ref = txreq.gref;
+ gop->source.domid = vsock->domid;
+ gop->source.offset = txreq.offset;
+
+ gop->dest.u.gmfn = virt_to_mfn(page_address(page));
+ gop->dest.domid = DOMID_SELF;
+ gop->dest.offset = txreq.offset;
+
+ gop->len = txreq.size;
+ gop->flags = GNTCOPY_source_gref;
+
+ gop++;
+
+ memcpy(&sockbk->pending_tx_info[pending_idx].req,
+ &txreq, sizeof(txreq));
+ sockbk->pending_tx_info[pending_idx].vsock = vsock;
+ *((u16 *)skb->data) = pending_idx;
+
+ __skb_put(skb, data_len);
+
+ skb_shinfo(skb)->nr_frags = ret;
+ if (data_len < txreq.size) {
+ skb_shinfo(skb)->nr_frags++;
+ frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
+ pending_idx);
+ } else {
+ frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
+ INVALID_PENDING_IDX);
+ }
+
+ sockbk->pending_cons++;
+
+ request_gop = xen_sockbk_get_requests(sockbk, vsock,
+ skb, txfrags, gop);
+ if (request_gop == NULL) {
+ kfree_skb(skb);
+ sockbk_tx_err(vsock, &txreq, idx);
+ continue;
+ }
+ gop = request_gop;
+
+ __skb_queue_tail(&sockbk->tx_queue, skb);
+
+ vsock->tx.req_cons = idx;
+ xen_sockbk_check_rx_xenvsock(vsock);
+
+ if (gop-sockbk->tx_copy_ops >= ARRAY_SIZE(sockbk->tx_copy_ops))
+ break;
+ }
+
+ return gop - sockbk->tx_copy_ops;
+}
+
+static void xen_sockbk_tx_submit(struct xen_sockbk *sockbk)
+{
+ struct gnttab_copy *gop = sockbk->tx_copy_ops;
+ struct sk_buff *skb;
+
+ while ((skb = __skb_dequeue(&sockbk->tx_queue)) != NULL) {
+ struct xen_sockif_tx_request *txp;
+ struct xenvsock *vsock;
+ u16 pending_idx;
+ unsigned data_len;
+
+ pending_idx = *((u16 *)skb->data);
+ vsock = sockbk->pending_tx_info[pending_idx].vsock;
+ txp = &sockbk->pending_tx_info[pending_idx].req;
+
+ /* Check the remap error code. */
+ if (unlikely(xen_sockbk_tx_check_gop(sockbk, skb, &gop))) {
+ dev_dbg(&vsock->xbdev->dev, "sockback grant failed.\n");
+ skb_shinfo(skb)->nr_frags = 0;
+ kfree_skb(skb);
+ continue;
+ }
+
+ data_len = skb->len;
+ memcpy(skb->data,
+ (void *)(idx_to_kaddr(sockbk, pending_idx)|txp->offset),
+ data_len);
+ if (data_len < txp->size) {
+ /* Append the packet payload as a fragment. */
+ txp->offset += data_len;
+ txp->size -= data_len;
+ } else {
+ /* Schedule a response immediately. */
+ xen_sockbk_idx_release(sockbk, pending_idx,
+ XEN_SOCKIF_RSP_OKAY);
+ }
+
+ xen_sockbk_fill_frags(sockbk, skb);
+
+ /* If the initial fragment was < PKT_PROT_LEN then
+ * pull through some bytes from the other fragments to
+ * increase the linear region to PKT_PROT_LEN bytes.
+ */
+ if (skb_headlen(skb) < PKT_PROT_LEN && skb_is_nonlinear(skb)) {
+ int target = min_t(int, skb->len, PKT_PROT_LEN);
+
+ __pskb_pull_tail(skb, target - skb_headlen(skb));
+ }
+
+ xenvsock_receive_skb(vsock, skb);
+ }
+}
+
+/* Called after sockfront has transmitted */
+static void xen_sockbk_tx_action(struct xen_sockbk *sockbk)
+{
+ unsigned nr_gops;
+
+ nr_gops = xen_sockbk_tx_build_gops(sockbk);
+
+ if (nr_gops == 0)
+ return;
+
+ gnttab_batch_copy(sockbk->tx_copy_ops, nr_gops);
+
+ xen_sockbk_tx_submit(sockbk);
+}
+
+static void xen_sockbk_idx_release(struct xen_sockbk *sockbk, u16 pending_idx,
+ u8 status)
+{
+ struct xenvsock *vsock;
+ struct pending_tx_info *pending_tx_info;
+ pending_ring_idx_t index;
+
+ /* Already complete? */
+ if (sockbk->mmap_pages[pending_idx] == NULL)
+ return;
+
+ pending_tx_info = &sockbk->pending_tx_info[pending_idx];
+
+ vsock = pending_tx_info->vsock;
+
+ make_tx_response(vsock, &pending_tx_info->req, status);
+
+ index = pending_index(sockbk->pending_prod++);
+ sockbk->pending_ring[index] = pending_idx;
+
+ xenvsock_put(vsock);
+
+ sockbk->mmap_pages[pending_idx]->mapping = 0;
+ put_page(sockbk->mmap_pages[pending_idx]);
+ sockbk->mmap_pages[pending_idx] = NULL;
+}
+
+static void make_tx_response(struct xenvsock *vsock,
+ struct xen_sockif_tx_request *txp,
+ s8 st)
+{
+ RING_IDX i = vsock->tx.rsp_prod_pvt;
+ struct xen_sockif_tx_response *resp;
+ int notify;
+
+ resp = RING_GET_RESPONSE(&vsock->tx, i);
+ resp->id = txp->id;
+ resp->status = st;
+
+ vsock->tx.rsp_prod_pvt = ++i;
+ RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vsock->tx, notify);
+ if (notify)
+ notify_remote_via_irq(vsock->irq);
+}
+
+static struct xen_sockif_rx_response *make_rx_response(struct xenvsock *vsock,
+ u16 id, s8 st,
+ u16 offset, u16 size,
+ u16 flags)
+{
+ RING_IDX i = vsock->rx.rsp_prod_pvt;
+ struct xen_sockif_rx_response *resp;
+
+ resp = RING_GET_RESPONSE(&vsock->rx, i);
+ resp->offset = offset;
+ resp->flags = flags;
+ resp->id = id;
+ resp->status = (s16)size;
+ if (st < 0)
+ resp->status = (s16)st;
+
+ vsock->rx.rsp_prod_pvt = ++i;
+
+ return resp;
+}
+
+static inline int rx_work_todo(struct xen_sockbk *sockbk)
+{
+ return !skb_queue_empty(&sockbk->rx_queue);
+}
+
+static inline int tx_work_todo(struct xen_sockbk *sockbk)
+{
+ if (((nr_pending_reqs(sockbk) + MAX_SKB_FRAGS) < MAX_PENDING_REQS) &&
+ !list_empty(&sockbk->sock_schedule_list))
+ return 1;
+
+ return 0;
+}
+
+static int xen_sockbk_kthread(void *data)
+{
+ struct xen_sockbk *sockbk = data;
+
+ while (!kthread_should_stop()) {
+ wait_event_interruptible(sockbk->wq,
+ rx_work_todo(sockbk) ||
+ tx_work_todo(sockbk) ||
+ kthread_should_stop());
+ cond_resched();
+
+ if (kthread_should_stop())
+ break;
+
+ if (rx_work_todo(sockbk))
+ xen_sockbk_rx_action(sockbk);
+
+ if (tx_work_todo(sockbk))
+ xen_sockbk_tx_action(sockbk);
+ }
+
+ return 0;
+}
+
+void xen_sockbk_unmap_frontend_rings(struct xenvsock *vsock)
+{
+ if (vsock->tx.sring)
+ xenbus_unmap_ring_vfree(vsock->xbdev, vsock->tx.sring);
+ if (vsock->rx.sring)
+ xenbus_unmap_ring_vfree(vsock->xbdev, vsock->rx.sring);
+}
+
+int xen_sockbk_map_frontend_rings(struct xenvsock *vsock,
+ grant_ref_t tx_ring_ref,
+ grant_ref_t rx_ring_ref)
+{
+ void *addr;
+ struct xen_sockif_tx_sring *txs;
+ struct xen_sockif_rx_sring *rxs;
+
+ int err = -ENOMEM;
+
+ err = xenbus_map_ring_valloc(vsock->xbdev, tx_ring_ref, &addr);
+ if (err)
+ goto err;
+
+ txs = (struct xen_sockif_tx_sring *)addr;
+ BACK_RING_INIT(&vsock->tx, txs, PAGE_SIZE);
+
+ err = xenbus_map_ring_valloc(vsock->xbdev, rx_ring_ref, &addr);
+ if (err)
+ goto err;
+
+ rxs = (struct xen_sockif_rx_sring *)addr;
+ BACK_RING_INIT(&vsock->rx, rxs, PAGE_SIZE);
+
+ vsock->rx_req_cons_peek = 0;
+
+ return 0;
+
+err:
+ xen_sockbk_unmap_frontend_rings(vsock);
+ return err;
+}
+
+static int __init sockback_init(void)
+{
+ int i;
+ int rc = 0;
+ int group;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ xen_sockbk_group_nr = num_online_cpus();
+ xen_sockbk = vzalloc(sizeof(*xen_sockbk) * xen_sockbk_group_nr);
+ if (!xen_sockbk)
+ return -ENOMEM;
+
+ for (group = 0; group < xen_sockbk_group_nr; group++) {
+ struct xen_sockbk *sockbk = &xen_sockbk[group];
+
+ skb_queue_head_init(&sockbk->rx_queue);
+ skb_queue_head_init(&sockbk->tx_queue);
+
+ init_timer(&sockbk->sock_timer);
+ sockbk->sock_timer.data = (unsigned long)sockbk;
+ sockbk->sock_timer.function = xen_sockbk_alarm;
+
+ sockbk->pending_cons = 0;
+ sockbk->pending_prod = MAX_PENDING_REQS;
+ for (i = 0; i < MAX_PENDING_REQS; i++)
+ sockbk->pending_ring[i] = i;
+
+ init_waitqueue_head(&sockbk->wq);
+ sockbk->task = kthread_create(xen_sockbk_kthread,
+ (void *)sockbk,
+ "sockback/%u", group);
+
+ if (IS_ERR(sockbk->task)) {
+ pr_alert("kthread_create() fails at sockback\n");
+ del_timer(&sockbk->sock_timer);
+ rc = PTR_ERR(sockbk->task);
+ goto failed_init;
+ }
+
+ kthread_bind(sockbk->task, group);
+
+ INIT_LIST_HEAD(&sockbk->sock_schedule_list);
+
+ spin_lock_init(&sockbk->sock_schedule_list_lock);
+
+ atomic_set(&sockbk->sockfront_count, 0);
+
+ wake_up_process(sockbk->task);
+ }
+
+ rc = xenvsock_xenbus_init();
+ if (rc)
+ goto failed_init;
+
+ rc = xensock_proto_server_init();
+ if (rc)
+ goto failed_init;
+
+ return 0;
+
+failed_init:
+ while (--group >= 0) {
+ struct xen_sockbk *sockbk = &xen_sockbk[group];
+
+ for (i = 0; i < MAX_PENDING_REQS; i++) {
+ if (sockbk->mmap_pages[i])
+ __free_page(sockbk->mmap_pages[i]);
+ }
+ del_timer(&sockbk->sock_timer);
+ kthread_stop(sockbk->task);
+ }
+ vfree(xen_sockbk);
+ return rc;
+}
+
+module_init(sockback_init);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS("xen-backend:vsock");
diff --git a/drivers/net/xen-sockback/xenbus.c b/drivers/net/xen-sockback/xenbus.c
new file mode 100644
index 0000000..7bd9a06
--- /dev/null
+++ b/drivers/net/xen-sockback/xenbus.c
@@ -0,0 +1,348 @@
+/*
+ * Xenbus code for sockif backend
+ *
+ * Copyright (C) 2005 Rusty Russell <rusty@rustcorp.com.au>
+ * Copyright (C) 2005 XenSource Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+*/
+#include "common.h"
+
+struct backend_info {
+ struct xenbus_device *dev;
+ struct xenvsock *vsock;
+ enum xenbus_state frontend_state;
+};
+
+static int connect_rings(struct backend_info *);
+static void connect(struct backend_info *);
+static int backend_create_xenvsock(struct backend_info *be);
+
+static int sockback_remove(struct xenbus_device *dev)
+{
+ struct backend_info *be = dev_get_drvdata(&dev->dev);
+
+ if (be->vsock) {
+ xenvsock_disconnect(be->vsock);
+ be->vsock = NULL;
+ }
+ kfree(be);
+ dev_set_drvdata(&dev->dev, NULL);
+ return 0;
+}
+
+
+/**
+ * Entry point to this code when a new device is created. Allocate the basic
+ * structures and switch to InitWait.
+ */
+static int sockback_probe(struct xenbus_device *dev,
+ const struct xenbus_device_id *id)
+{
+ const char *message;
+ struct xenbus_transaction xbt;
+ int err;
+ int sg;
+ struct backend_info *be = kzalloc(sizeof(*be), GFP_KERNEL);
+
+ if (!be) {
+ xenbus_dev_fatal(dev, -ENOMEM,
+ "allocating backend structure");
+ return -ENOMEM;
+ }
+
+ be->dev = dev;
+ dev_set_drvdata(&dev->dev, be);
+
+ sg = 1;
+
+ do {
+ err = xenbus_transaction_start(&xbt);
+ if (err) {
+ xenbus_dev_fatal(dev, err, "starting transaction");
+ goto fail;
+ }
+
+ /* We support rx-copy path. */
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-rx-copy", "%d", 1);
+ if (err) {
+ message = "writing feature-rx-copy";
+ goto abort_transaction;
+ }
+
+ /* We don't support rx-flip path (except old guests who don't
+ * grok this feature flag).
+ */
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-rx-flip", "%d", 0);
+ if (err) {
+ message = "writing feature-rx-flip";
+ goto abort_transaction;
+ }
+
+ err = xenbus_transaction_end(xbt, 0);
+ } while (err == -EAGAIN);
+
+ if (err) {
+ xenbus_dev_fatal(dev, err, "completing transaction");
+ goto fail;
+ }
+
+ err = xenbus_switch_state(dev, XenbusStateInitWait);
+ if (err)
+ goto fail;
+
+ return 0;
+
+abort_transaction:
+ xenbus_transaction_end(xbt, 1);
+ xenbus_dev_fatal(dev, err, "%s", message);
+fail:
+ pr_debug("failed");
+ sockback_remove(dev);
+ return err;
+}
+
+static int backend_create_xenvsock(struct backend_info *be)
+{
+ int err;
+ long handle;
+ struct xenbus_device *dev = be->dev;
+
+ if (be->vsock != NULL)
+ return 0;
+
+ err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle);
+ if (err != 1) {
+ err = -EINVAL;
+ xenbus_dev_fatal(dev, err, "reading handle");
+ goto fail;
+ }
+
+ be->vsock = xenvsock_alloc(&dev->dev, dev->otherend_id, handle);
+ if (IS_ERR(be->vsock)) {
+ err = PTR_ERR(be->vsock);
+ be->vsock = NULL;
+ xenbus_dev_fatal(dev, err, "creating interface");
+ goto fail;
+ }
+
+ /* setup back pointer */
+ be->vsock->xbdev = dev;
+
+ err = 0;
+fail:
+ return err;
+}
+
+
+static void disconnect_backend(struct xenbus_device *dev)
+{
+ struct backend_info *be = dev_get_drvdata(&dev->dev);
+
+ if (be->vsock) {
+ xenvsock_disconnect(be->vsock);
+ be->vsock = NULL;
+ }
+}
+
+/**
+ * Callback received when the frontend's state changes.
+ */
+static void frontend_changed(struct xenbus_device *dev,
+ enum xenbus_state frontend_state)
+{
+ struct backend_info *be = dev_get_drvdata(&dev->dev);
+
+ pr_debug("frontend state %s", xenbus_strstate(frontend_state));
+
+ be->frontend_state = frontend_state;
+
+ switch (frontend_state) {
+ case XenbusStateInitialising:
+ if (dev->state == XenbusStateClosed) {
+ pr_alert("%s: %s: prepare for reconnect\n",
+ __func__, dev->nodename);
+ xenbus_switch_state(dev, XenbusStateInitWait);
+ }
+ break;
+
+ case XenbusStateInitialised:
+ case XenbusStateConnected:
+ /* Ensure we connect even when two watches fire in
+ * close succession and we miss the intermediate value
+ * of frontend_state.
+ */
+ if (dev->state == XenbusStateConnected)
+ break;
+
+ /* Enforce precondition before potential leak point.
+ * disconnect_backend() is idempotent.
+ */
+ disconnect_backend(dev);
+
+ if (backend_create_xenvsock(be))
+ break;
+
+ connect(be);
+ break;
+
+ case XenbusStateClosing:
+ xenbus_switch_state(dev, XenbusStateClosing);
+ break;
+
+ case XenbusStateClosed:
+ disconnect_backend(dev);
+ xenbus_switch_state(dev, XenbusStateClosed);
+ if (xenbus_dev_is_online(dev))
+ break;
+ /* fall through if not online */
+ case XenbusStateUnknown:
+ device_unregister(&dev->dev);
+ break;
+
+ default:
+ xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
+ frontend_state);
+ break;
+ }
+}
+
+static void xen_sock_read_rate(struct xenbus_device *dev,
+ unsigned long *bytes, unsigned long *usec)
+{
+ char *s, *e;
+ unsigned long b, u;
+ char *ratestr;
+
+ /* Default to unlimited bandwidth. */
+ *bytes = ~0UL;
+ *usec = 0;
+
+ ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
+ if (IS_ERR(ratestr))
+ return;
+
+ s = ratestr;
+ e = strchr(s, ',');
+ if (e == NULL)
+ goto fail;
+
+ e[0] = '\0';
+
+ if (kstrtoul(s, 10, &b))
+ goto fail;
+
+ s = e + 1;
+ if (kstrtoul(s, 10, &u))
+ goto fail;
+
+ *bytes = b;
+ *usec = u;
+
+ kfree(ratestr);
+ return;
+
+ fail:
+ pr_warn("Failed to parse socket data rate limit. Traffic unlimited.\n");
+ kfree(ratestr);
+}
+
+static void connect(struct backend_info *be)
+{
+ int err;
+ struct xenbus_device *dev = be->dev;
+
+ err = connect_rings(be);
+ if (err)
+ return;
+
+ xen_sock_read_rate(dev, &be->vsock->credit_bytes,
+ &be->vsock->credit_usec);
+ be->vsock->remaining_credit = be->vsock->credit_bytes;
+
+ sockif_wake_queue(be->vsock->dev);
+ xenbus_switch_state(dev, XenbusStateConnected);
+}
+
+static int connect_rings(struct backend_info *be)
+{
+ struct xenvsock *vsock = be->vsock;
+ struct xenbus_device *dev = be->dev;
+ unsigned long tx_ring_ref, rx_ring_ref;
+ unsigned int evtchn, rx_copy;
+ int err;
+ int val;
+
+ err = xenbus_gather(XBT_NIL, dev->otherend,
+ "tx-ring-ref", "%lu", &tx_ring_ref,
+ "rx-ring-ref", "%lu", &rx_ring_ref,
+ "event-channel", "%u", &evtchn, NULL);
+ if (err) {
+ xenbus_dev_fatal(dev, err,
+ "reading %s/ring-ref and event-channel",
+ dev->otherend);
+ return err;
+ }
+
+ err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u",
+ &rx_copy);
+ if (err == -ENOENT) {
+ err = 0;
+ rx_copy = 0;
+ }
+ if (err < 0) {
+ xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy",
+ dev->otherend);
+ return err;
+ }
+ if (!rx_copy)
+ return -EOPNOTSUPP;
+
+ if (vsock->dev->tx_queue_len != 0) {
+ if (xenbus_scanf(XBT_NIL, dev->otherend,
+ "feature-rx-notify", "%d", &val) < 0)
+ val = 0;
+ if (val)
+ vsock->can_queue = 1;
+ else
+ /* Must be non-zero for pfifo_fast to work. */
+ vsock->dev->tx_queue_len = 1;
+ }
+
+ /* Map the shared frame, irq etc. */
+ err = xenvsock_connect(vsock, tx_ring_ref, rx_ring_ref, evtchn);
+ if (err) {
+ xenbus_dev_fatal(dev, err,
+ "mapping shared-frames %lu/%lu port %u",
+ tx_ring_ref, rx_ring_ref, evtchn);
+ return err;
+ }
+ return 0;
+}
+
+/* ** Driver Registration ** */
+static const struct xenbus_device_id sockback_ids[] = {
+ { "vsock" },
+ { "" }
+};
+
+static DEFINE_XENBUS_DRIVER(sockback, ,
+ .probe = sockback_probe,
+ .remove = sockback_remove,
+ .otherend_changed = frontend_changed,
+);
+
+int xenvsock_xenbus_init(void)
+{
+ return xenbus_register_backend(&sockback_driver);
+}
diff --git a/include/xen/interface/io/sockif.h b/include/xen/interface/io/sockif.h
new file mode 100644
index 0000000..c12ce11
--- /dev/null
+++ b/include/xen/interface/io/sockif.h
@@ -0,0 +1,74 @@
+/******************************************************************************
+ * sockif.h
+ *
+ * Unified xensock I/O interface for Xen guest OSes.
+ *
+ */
+#ifndef __XEN_PUBLIC_IO_SOCKIF_H__
+#define __XEN_PUBLIC_IO_SOCKIF_H__
+
+#include <linux/types.h>
+#include <linux/spinlock.h>
+
+#include <net/sock.h>
+
+#include <xen/interface/io/ring.h>
+#include <xen/interface/grant_table.h>
+
+/*
+ * REQUEST CODES.
+ */
+#define SOCKIF_OP_SENDMSG 0
+#define SOCKIF_OP_RECVMSG 1
+
+#define SOCKIF_MAX_PAGES_PER_REQUEST 10
+
+#define SOCKIF_DEV_ID_CNT 5
+
+
+/* Packet continues in the next request descriptor. */
+#define _XEN_SOCKTXF_more_data (2)
+#define XEN_SOCKTXF_more_data (1U<<_XEN_SOCKTXF_more_data)
+
+struct xen_sockif_tx_request {
+ grant_ref_t gref; /* Reference to buffer page */
+ uint16_t offset; /* Offset within buffer page */
+ uint16_t flags; /* XEN_SOCKTXF_* */
+ uint16_t id; /* Echoed in response message. */
+ uint16_t size; /* Packet size in bytes. */
+};
+
+struct xen_sockif_tx_response {
+ uint16_t id;
+ int16_t status; /* XEN_SOCKIF_RSP_* */
+};
+
+struct xen_sockif_rx_request {
+ uint16_t id; /* Echoed in response message. */
+ grant_ref_t gref; /* Reference to incoming granted frame */
+};
+
+/* Packet continues in the next request descriptor. */
+#define _XEN_SOCKRXF_more_data (0)
+#define XEN_SOCKRXF_more_data (1U<<_XEN_SOCKRXF_more_data)
+
+struct xen_sockif_rx_response {
+ uint16_t id;
+ uint16_t offset; /* Offset in page of start of received packet */
+ uint16_t flags; /* XEN_SOCKRXF_* */
+ int16_t status; /* -ve: BLKIF_RSP_* ; +ve: Rx'ed pkt size. */
+};
+
+DEFINE_RING_TYPES(xen_sockif_tx,
+ struct xen_sockif_tx_request,
+ struct xen_sockif_tx_response);
+
+DEFINE_RING_TYPES(xen_sockif_rx,
+ struct xen_sockif_rx_request,
+ struct xen_sockif_rx_response);
+
+#define XEN_SOCKIF_RSP_DROPPED -2
+#define XEN_SOCKIF_RSP_ERROR -1
+#define XEN_SOCKIF_RSP_OKAY 0
+
+#endif /* __XEN_PUBLIC_IO_SOCKIF_H__ */
--
1.8.2.rc2
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 3/3] xen-sockfront: add support of the xen-sockfront driver
2014-08-08 11:32 [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers Oleksandr Dmytryshyn
2014-08-08 11:32 ` [PATCH 1/3] net: introduce new socket support: xensock Oleksandr Dmytryshyn
2014-08-08 11:32 ` [PATCH 2/3] xen-sockback: add support of the xen-sockback driver Oleksandr Dmytryshyn
@ 2014-08-08 11:32 ` Oleksandr Dmytryshyn
2014-08-08 12:36 ` [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers David Vrabel
` (2 subsequent siblings)
5 siblings, 0 replies; 12+ messages in thread
From: Oleksandr Dmytryshyn @ 2014-08-08 11:32 UTC (permalink / raw)
To: Ian Campbell, Stefano Stabellini, Tim Deegan, xen-devel
This driver will allow to use xensock sockets for the
client application for the domU domain.
Signed-off-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>
---
drivers/net/Kconfig | 17 +-
drivers/net/Makefile | 1 +
drivers/net/xen-sockfront.c | 1364 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1381 insertions(+), 1 deletion(-)
create mode 100644 drivers/net/xen-sockfront.c
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index e643f42..887fe4b 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -348,6 +348,21 @@ config XEN_NETDEV_BACKEND
compile this driver as a module, chose M here: the module
will be called xen-netback.
+config XEN_SOCKDEV_FRONTEND
+ tristate "Xen frontend socket device"
+ depends on XEN_DOMU
+ select XEN_SOCKDEV_PROTO
+ help
+ This driver provides support for Xen socket devices exported
+ by a Xen socket driver domain (often domain 0).
+
+ The corresponding Linux backend driver is enabled by the
+ XEN_SOCKDEV_BACKEND option.
+
+ If you are compiling a kernel for use as Xen guest, you
+ should say Y here. To compile this driver as a module, chose
+ M here: the module will be called xen-sockfront.
+
config XEN_SOCKDEV_BACKEND
tristate "Xen backend socket device"
depends on XEN_BACKEND
@@ -369,7 +384,7 @@ config XEN_SOCKDEV_BACKEND
config XEN_SOCKDEV_PROTO
bool
default n
- depends on XEN_SOCKDEV_BACKEND
+ depends on XEN_SOCKDEV_BACKEND || XEN_SOCKDEV_FRONTEND
config VMXNET3
tristate "VMware VMXNET3 ethernet driver"
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 96c6c97..8c3eee8 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
obj-$(CONFIG_XEN_NETDEV_BACKEND) += xen-netback/
obj-$(CONFIG_XEN_SOCKDEV_PROTO) += xensock/
+obj-$(CONFIG_XEN_SOCKDEV_FRONTEND) += xen-sockfront.o
obj-$(CONFIG_XEN_SOCKDEV_BACKEND) += xen-sockback/
obj-$(CONFIG_USB_CATC) += usb/
diff --git a/drivers/net/xen-sockfront.c b/drivers/net/xen-sockfront.c
new file mode 100644
index 0000000..2aa65e4
--- /dev/null
+++ b/drivers/net/xen-sockfront.c
@@ -0,0 +1,1364 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/moduleparam.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+
+#include <net/xensock.h>
+#include <net/af_xensock.h>
+
+#include <asm/xen/page.h>
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+#include <xen/events.h>
+#include <xen/page.h>
+#include <xen/grant_table.h>
+
+#include <xen/interface/io/sockif.h>
+#include <xen/interface/memory.h>
+#include <xen/interface/grant_table.h>
+
+struct sockfront_cb {
+ int pull_to;
+};
+
+#define SOCKFRONT_SKB_CB(skb) ((struct sockfront_cb *)((skb)->cb))
+
+#define RX_COPY_THRESHOLD 256
+
+#define GRANT_INVALID_REF 0
+
+#define SOCK_TX_RING_SIZE __CONST_RING_SIZE(xen_sockif_tx, PAGE_SIZE)
+#define SOCK_RX_RING_SIZE __CONST_RING_SIZE(xen_sockif_rx, PAGE_SIZE)
+#define TX_MAX_TARGET min_t(int, SOCK_TX_RING_SIZE, 256)
+
+struct sockfront_info {
+ struct list_head list;
+ struct xen_sock_dev *sockdev;
+ unsigned int irq;
+
+ struct tasklet_struct rx_poll;
+
+ unsigned int evtchn;
+ struct xenbus_device *xbdev;
+
+ spinlock_t tx_lock; /* transmitter lock */
+ struct xen_sockif_tx_front_ring tx;
+ int tx_ring_ref;
+
+ /* {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries
+ * are linked from tx_skb_freelist through skb_entry.link.
+ *
+ * NB. Freelist index entries are always going to be less than
+ * PAGE_OFFSET, whereas pointers to skbs will always be equal or
+ * greater than PAGE_OFFSET: we use this property to distinguish
+ * them.
+ */
+ union skb_entry {
+ struct sk_buff *skb;
+ unsigned long link;
+ } tx_skbs[SOCK_TX_RING_SIZE];
+ grant_ref_t gref_tx_head;
+ grant_ref_t grant_tx_ref[SOCK_TX_RING_SIZE];
+ unsigned tx_skb_freelist;
+
+ spinlock_t rx_lock ____cacheline_aligned_in_smp;
+ struct xen_sockif_rx_front_ring rx;
+ int rx_ring_ref;
+
+ /* Receive-ring batched refills. */
+#define RX_MIN_TARGET 8
+#define RX_DFL_MIN_TARGET 64
+#define RX_MAX_TARGET min_t(int, SOCK_RX_RING_SIZE, 256)
+ unsigned rx_min_target, rx_max_target, rx_target;
+ struct sk_buff_head rx_batch;
+
+ struct timer_list rx_refill_timer;
+
+ struct sk_buff *rx_skbs[SOCK_RX_RING_SIZE];
+ grant_ref_t gref_rx_head;
+ grant_ref_t grant_rx_ref[SOCK_RX_RING_SIZE];
+
+ unsigned long rx_pfn_array[SOCK_RX_RING_SIZE];
+ struct multicall_entry rx_mcl[SOCK_RX_RING_SIZE+1];
+ struct mmu_update rx_mmu[SOCK_RX_RING_SIZE];
+};
+
+struct sockfront_rx_info {
+ struct xen_sockif_rx_response rx;
+};
+
+static void skb_entry_set_link(union skb_entry *list, unsigned short id)
+{
+ list->link = id;
+}
+
+static int skb_entry_is_link(const union skb_entry *list)
+{
+ BUILD_BUG_ON(sizeof(list->skb) != sizeof(list->link));
+ return (unsigned long)list->skb < PAGE_OFFSET;
+}
+
+/* Access macros for acquiring freeing slots in tx_skbs[] */
+
+static void add_id_to_freelist(unsigned *head, union skb_entry *list,
+ unsigned short id)
+{
+ skb_entry_set_link(&list[id], *head);
+ *head = id;
+}
+
+static unsigned short get_id_from_freelist(unsigned *head,
+ union skb_entry *list)
+{
+ unsigned int id = *head;
+ *head = list[id].link;
+ return id;
+}
+
+static int xensock_rxidx(RING_IDX idx)
+{
+ return idx & (SOCK_RX_RING_SIZE - 1);
+}
+
+static struct sk_buff *xensock_get_rx_skb(struct sockfront_info *np,
+ RING_IDX ri)
+{
+ int i = xensock_rxidx(ri);
+ struct sk_buff *skb = np->rx_skbs[i];
+
+ np->rx_skbs[i] = NULL;
+ return skb;
+}
+
+static grant_ref_t xensock_get_rx_ref(struct sockfront_info *np,
+ RING_IDX ri)
+{
+ int i = xensock_rxidx(ri);
+ grant_ref_t ref = np->grant_rx_ref[i];
+
+ np->grant_rx_ref[i] = GRANT_INVALID_REF;
+ return ref;
+}
+
+static void rx_refill_timeout(unsigned long data)
+{
+ struct xen_sock_dev *dev = (struct xen_sock_dev *)data;
+ struct sockfront_info *np = xensock_dev_priv(dev);
+
+ tasklet_schedule(&np->rx_poll);
+}
+
+static int sockfront_tx_slot_available(struct sockfront_info *np)
+{
+ return (np->tx.req_prod_pvt - np->tx.rsp_cons) <
+ (TX_MAX_TARGET - MAX_SKB_FRAGS - 2);
+}
+
+static void xensock_maybe_wake_tx(struct xen_sock_dev *dev)
+{
+ struct sockfront_info *np = xensock_dev_priv(dev);
+
+ if (unlikely(sockif_queue_stopped(dev)) &&
+ sockfront_tx_slot_available(np))
+ sockif_wake_queue(dev);
+}
+
+static void xensock_alloc_rx_buffers(struct xen_sock_dev *dev)
+{
+ unsigned short id;
+ struct sockfront_info *np = xensock_dev_priv(dev);
+ struct sk_buff *skb;
+ struct page *page;
+ int i, batch_target, notify;
+ RING_IDX req_prod = np->rx.req_prod_pvt;
+ grant_ref_t ref;
+ unsigned long pfn;
+ void *vaddr;
+ struct xen_sockif_rx_request *req;
+
+ if (unlikely(!sockif_carrier_ok(dev)))
+ return;
+
+ /* Allocate skbuffs greedily, even though we batch updates to the
+ * receive ring. This creates a less bursty demand on the memory
+ * allocator, so should reduce the chance of failed allocation requests
+ * both for ourself and for other kernel subsystems.
+ */
+ batch_target = np->rx_target - (req_prod - np->rx.rsp_cons);
+ for (i = skb_queue_len(&np->rx_batch); i < batch_target; i++) {
+ skb = alloc_skb(RX_COPY_THRESHOLD + NET_IP_ALIGN + NET_SKB_PAD,
+ GFP_ATOMIC | __GFP_NOWARN);
+ if (unlikely(!skb))
+ goto no_skb;
+
+ /* Align ip header to a 16 bytes boundary */
+ skb_reserve(skb, NET_IP_ALIGN);
+
+ page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
+ if (!page) {
+ kfree_skb(skb);
+no_skb:
+ /* Any skbuffs queued for refill? Force them out. */
+ if (i != 0)
+ goto refill;
+ /* Could not allocate any skbuffs. Try again later. */
+ mod_timer(&np->rx_refill_timer,
+ jiffies + (HZ/10));
+ break;
+ }
+
+ __skb_fill_page_desc(skb, 0, page, 0, 0);
+ skb_shinfo(skb)->nr_frags = 1;
+ __skb_queue_tail(&np->rx_batch, skb);
+ }
+
+ /* Is the batch large enough to be worthwhile? */
+ if (i < (np->rx_target/2)) {
+ if (req_prod > np->rx.sring->req_prod)
+ goto push;
+ return;
+ }
+
+ /* Adjust our fill target if we risked running out of buffers. */
+ if ((req_prod - np->rx.sring->rsp_prod) < (np->rx_target / 4)) {
+ np->rx_target *= 2;
+ if (np->rx_target > np->rx_max_target)
+ np->rx_target = np->rx_max_target;
+ }
+
+ refill:
+ for (i = 0; ; i++) {
+ skb = __skb_dequeue(&np->rx_batch);
+ if (skb == NULL)
+ break;
+
+ id = xensock_rxidx(req_prod + i);
+
+ BUG_ON(np->rx_skbs[id]);
+ np->rx_skbs[id] = skb;
+
+ ref = gnttab_claim_grant_reference(&np->gref_rx_head);
+ BUG_ON((signed short)ref < 0);
+ np->grant_rx_ref[id] = ref;
+
+ pfn = page_to_pfn(skb_frag_page(&skb_shinfo(skb)->frags[0]));
+ vaddr = page_address(skb_frag_page(&skb_shinfo(skb)->frags[0]));
+
+ req = RING_GET_REQUEST(&np->rx, req_prod + i);
+ gnttab_grant_foreign_access_ref(ref,
+ np->xbdev->otherend_id,
+ pfn_to_mfn(pfn),
+ 0);
+
+ req->id = id;
+ req->gref = ref;
+ }
+
+ wmb(); /* barrier so backend seens requests */
+
+ /* Above is a suitable barrier to ensure backend will see requests. */
+ np->rx.req_prod_pvt = req_prod + i;
+ push:
+ RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->rx, notify);
+ if (notify)
+ notify_remote_via_irq(np->irq);
+}
+
+static void xensock_tx_buf_gc(struct xen_sock_dev *dev)
+{
+ RING_IDX cons, prod;
+ unsigned short id;
+ struct sockfront_info *np = xensock_dev_priv(dev);
+ struct sk_buff *skb;
+
+ BUG_ON(!sockif_carrier_ok(dev));
+
+ do {
+ prod = np->tx.sring->rsp_prod;
+ rmb(); /* Ensure we see responses up to 'rp'. */
+
+ for (cons = np->tx.rsp_cons; cons != prod; cons++) {
+ struct xen_sockif_tx_response *txrsp;
+
+ txrsp = RING_GET_RESPONSE(&np->tx, cons);
+
+ id = txrsp->id;
+ skb = np->tx_skbs[id].skb;
+ if (unlikely(gnttab_query_foreign_access(
+ np->grant_tx_ref[id]) != 0)) {
+ pr_alert("%s: warning -- grant still in use "
+ "by backend domain.\n", __func__);
+ BUG();
+ }
+ gnttab_end_foreign_access_ref(
+ np->grant_tx_ref[id], GNTMAP_readonly);
+ gnttab_release_grant_reference(
+ &np->gref_tx_head, np->grant_tx_ref[id]);
+ np->grant_tx_ref[id] = GRANT_INVALID_REF;
+ add_id_to_freelist(&np->tx_skb_freelist, np->tx_skbs,
+ id);
+ dev_kfree_skb_irq(skb);
+ }
+
+ np->tx.rsp_cons = prod;
+
+ /* Set a new event, then check for race with update of tx_cons.
+ * Note that it is essential to schedule a callback, no matter
+ * how few buffers are pending. Even if there is space in the
+ * transmit ring, higher layers may be blocked because too much
+ * data is outstanding: in such cases notification from Xen is
+ * likely to be the only kick that we'll get.
+ */
+ np->tx.sring->rsp_event =
+ prod + ((np->tx.sring->req_prod - prod) >> 1) + 1;
+ mb(); /* update shared area */
+ } while ((cons == prod) && (prod != np->tx.sring->rsp_prod));
+
+ xensock_maybe_wake_tx(dev);
+}
+
+static void xensock_make_frags(struct sk_buff *skb, struct xen_sock_dev *dev,
+ struct xen_sockif_tx_request *tx)
+{
+ struct sockfront_info *np = xensock_dev_priv(dev);
+ char *data = skb->data;
+ unsigned long mfn;
+ RING_IDX prod = np->tx.req_prod_pvt;
+ int frags = skb_shinfo(skb)->nr_frags;
+ unsigned int offset = offset_in_page(data);
+ unsigned int len = skb_headlen(skb);
+ unsigned int id;
+ grant_ref_t ref;
+ int i;
+
+ /* While the header overlaps a page boundary (including being
+ * larger than a page), split it it into page-sized chunks.
+ */
+ while (len > PAGE_SIZE - offset) {
+ tx->size = PAGE_SIZE - offset;
+ tx->flags |= XEN_SOCKTXF_more_data;
+ len -= tx->size;
+ data += tx->size;
+ offset = 0;
+
+ id = get_id_from_freelist(&np->tx_skb_freelist, np->tx_skbs);
+ np->tx_skbs[id].skb = skb_get(skb);
+ tx = RING_GET_REQUEST(&np->tx, prod++);
+ tx->id = id;
+ ref = gnttab_claim_grant_reference(&np->gref_tx_head);
+ BUG_ON((signed short)ref < 0);
+
+ mfn = virt_to_mfn(data);
+ gnttab_grant_foreign_access_ref(ref, np->xbdev->otherend_id,
+ mfn, GNTMAP_readonly);
+
+ tx->gref = ref;
+ np->grant_tx_ref[id] = ref;
+ tx->offset = offset;
+ tx->size = len;
+ tx->flags = 0;
+ }
+
+ /* Grant backend access to each skb fragment page. */
+ for (i = 0; i < frags; i++) {
+ skb_frag_t *frag = skb_shinfo(skb)->frags + i;
+ struct page *page = skb_frag_page(frag);
+
+ len = skb_frag_size(frag);
+ offset = frag->page_offset;
+
+ /* Data must not cross a page boundary. */
+ BUG_ON(len + offset > PAGE_SIZE<<compound_order(page));
+
+ /* Skip unused frames from start of page */
+ page += offset >> PAGE_SHIFT;
+ offset &= ~PAGE_MASK;
+
+ while (len > 0) {
+ unsigned long bytes;
+
+ BUG_ON(offset >= PAGE_SIZE);
+
+ bytes = PAGE_SIZE - offset;
+ if (bytes > len)
+ bytes = len;
+
+ tx->flags |= XEN_SOCKTXF_more_data;
+
+ id = get_id_from_freelist(&np->tx_skb_freelist,
+ np->tx_skbs);
+ np->tx_skbs[id].skb = skb_get(skb);
+ tx = RING_GET_REQUEST(&np->tx, prod++);
+ tx->id = id;
+ ref = gnttab_claim_grant_reference(&np->gref_tx_head);
+ BUG_ON((signed short)ref < 0);
+
+ mfn = pfn_to_mfn(page_to_pfn(page));
+ gnttab_grant_foreign_access_ref(ref,
+ np->xbdev->otherend_id,
+ mfn, GNTMAP_readonly);
+
+ tx->gref = ref;
+ np->grant_tx_ref[id] = ref;
+ tx->offset = offset;
+ tx->size = bytes;
+ tx->flags = 0;
+
+ offset += bytes;
+ len -= bytes;
+
+ /* Next frame */
+ if (offset == PAGE_SIZE && len) {
+ BUG_ON(!PageCompound(page));
+ page++;
+ offset = 0;
+ }
+ }
+ }
+
+ np->tx.req_prod_pvt = prod;
+}
+
+/* Count how many ring slots are required to send the frags of this
+ * skb. Each frag might be a compound page.
+ */
+static int xensock_count_skb_frag_slots(struct sk_buff *skb)
+{
+ int i, frags = skb_shinfo(skb)->nr_frags;
+ int pages = 0;
+
+ for (i = 0; i < frags; i++) {
+ skb_frag_t *frag = skb_shinfo(skb)->frags + i;
+ unsigned long size = skb_frag_size(frag);
+ unsigned long offset = frag->page_offset;
+
+ /* Skip unused frames from start of page */
+ offset &= ~PAGE_MASK;
+
+ pages += PFN_UP(offset + size);
+ }
+
+ return pages;
+}
+
+static int xensock_start_xmit(struct sk_buff *skb, struct xen_sock_dev *dev)
+{
+ unsigned short id;
+ struct sockfront_info *np = xensock_dev_priv(dev);
+ struct xen_sockif_tx_request *tx;
+ char *data = skb->data;
+ RING_IDX i;
+ grant_ref_t ref;
+ unsigned long mfn;
+ int notify;
+ int slots;
+ unsigned int offset = offset_in_page(data);
+ unsigned int len = skb_headlen(skb);
+ unsigned long flags;
+
+ slots = DIV_ROUND_UP(offset + len, PAGE_SIZE) +
+ xensock_count_skb_frag_slots(skb);
+ if (unlikely(slots > MAX_SKB_FRAGS + 1)) {
+ pr_err_ratelimited("xensock: skb rides the rocket: %d slots\n",
+ slots);
+ goto drop;
+ }
+
+ spin_lock_irqsave(&np->tx_lock, flags);
+
+ if (unlikely(!sockif_carrier_ok(dev))) {
+ spin_unlock_irqrestore(&np->tx_lock, flags);
+ goto drop;
+ }
+
+ i = np->tx.req_prod_pvt;
+
+ id = get_id_from_freelist(&np->tx_skb_freelist, np->tx_skbs);
+ np->tx_skbs[id].skb = skb;
+
+ tx = RING_GET_REQUEST(&np->tx, i);
+
+ tx->id = id;
+ ref = gnttab_claim_grant_reference(&np->gref_tx_head);
+ BUG_ON((signed short)ref < 0);
+ mfn = virt_to_mfn(data);
+ gnttab_grant_foreign_access_ref(
+ ref, np->xbdev->otherend_id, mfn, GNTMAP_readonly);
+ tx->gref = ref;
+ np->grant_tx_ref[id] = ref;
+ tx->offset = offset;
+ tx->size = len;
+
+ tx->flags = 0;
+
+ np->tx.req_prod_pvt = i + 1;
+
+ xensock_make_frags(skb, dev, tx);
+ tx->size = skb->len;
+
+ RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->tx, notify);
+ if (notify)
+ notify_remote_via_irq(np->irq);
+
+ /* Note: It is not safe to access skb after xensock_tx_buf_gc()! */
+ xensock_tx_buf_gc(dev);
+
+ if (!sockfront_tx_slot_available(np))
+ sockif_stop_queue(dev);
+
+ spin_unlock_irqrestore(&np->tx_lock, flags);
+
+ return 0;
+
+ drop:
+ dev_kfree_skb(skb);
+ return 0;
+}
+
+static void xensock_move_rx_slot(struct sockfront_info *np, struct sk_buff *skb,
+ grant_ref_t ref)
+{
+ int new = xensock_rxidx(np->rx.req_prod_pvt);
+
+ BUG_ON(np->rx_skbs[new]);
+ np->rx_skbs[new] = skb;
+ np->grant_rx_ref[new] = ref;
+ RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->id = new;
+ RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->gref = ref;
+ np->rx.req_prod_pvt++;
+}
+
+static int xensock_get_responses(struct sockfront_info *np,
+ struct sockfront_rx_info *rinfo, RING_IDX rp,
+ struct sk_buff_head *list)
+{
+ struct xen_sockif_rx_response *rx = &rinfo->rx;
+ struct device *dev = &np->xbdev->dev;
+ RING_IDX cons = np->rx.rsp_cons;
+ struct sk_buff *skb = xensock_get_rx_skb(np, cons);
+ grant_ref_t ref = xensock_get_rx_ref(np, cons);
+ int max = MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD);
+ int frags = 1;
+ int err = 0;
+ unsigned long ret;
+
+ for (;;) {
+ if (unlikely(rx->status < 0 ||
+ rx->offset + rx->status > PAGE_SIZE)) {
+ dev_warn_ratelimited(dev, "rx->offset: %x, size: %u\n",
+ rx->offset, rx->status);
+ xensock_move_rx_slot(np, skb, ref);
+ err = -EINVAL;
+ goto next;
+ }
+
+ /* This definitely indicates a bug, either in this driver or in
+ * the backend driver. In future this should flag the bad
+ * situation to the system controller to reboot the backed.
+ */
+ if (ref == GRANT_INVALID_REF) {
+ dev_warn_ratelimited(dev, "Bad rx response id %d.\n",
+ rx->id);
+ err = -EINVAL;
+ goto next;
+ }
+
+ ret = gnttab_end_foreign_access_ref(ref, 0);
+ BUG_ON(!ret);
+
+ gnttab_release_grant_reference(&np->gref_rx_head, ref);
+
+ __skb_queue_tail(list, skb);
+
+next:
+ if (!(rx->flags & XEN_SOCKRXF_more_data))
+ break;
+
+ if (cons + frags == rp) {
+ dev_warn_ratelimited(dev, "Need more frags\n");
+ err = -ENOENT;
+ break;
+ }
+
+ rx = RING_GET_RESPONSE(&np->rx, cons + frags);
+ skb = xensock_get_rx_skb(np, cons + frags);
+ ref = xensock_get_rx_ref(np, cons + frags);
+ frags++;
+ }
+
+ if (unlikely(frags > max)) {
+ dev_warn_ratelimited(dev, "Too many frags\n");
+ err = -E2BIG;
+ }
+
+ if (unlikely(err))
+ np->rx.rsp_cons = cons + frags;
+
+ return err;
+}
+
+static RING_IDX xensock_fill_frags(struct sockfront_info *np,
+ struct sk_buff *skb,
+ struct sk_buff_head *list)
+{
+ struct skb_shared_info *shinfo = skb_shinfo(skb);
+ int nr_frags = shinfo->nr_frags;
+ RING_IDX cons = np->rx.rsp_cons;
+ struct sk_buff *nskb;
+
+ while ((nskb = __skb_dequeue(list))) {
+ struct xen_sockif_rx_response *rx =
+ RING_GET_RESPONSE(&np->rx, ++cons);
+ skb_frag_t *nfrag = &skb_shinfo(nskb)->frags[0];
+
+ __skb_fill_page_desc(skb, nr_frags,
+ skb_frag_page(nfrag),
+ rx->offset, rx->status);
+
+ skb->data_len += rx->status;
+
+ skb_shinfo(nskb)->nr_frags = 0;
+ kfree_skb(nskb);
+
+ nr_frags++;
+ }
+
+ shinfo->nr_frags = nr_frags;
+ return cons;
+}
+
+static int handle_incoming_queue(struct xen_sock_dev *dev,
+ struct sk_buff_head *rxq)
+{
+ int packets_dropped = 0;
+ struct sk_buff *skb;
+
+ while ((skb = __skb_dequeue(rxq)) != NULL) {
+ int pull_to = SOCKFRONT_SKB_CB(skb)->pull_to;
+
+ __pskb_pull_tail(skb, pull_to - skb_headlen(skb));
+
+ /* Pass it up. */
+ xensock_dev_queue_rx_skb(skb, dev);
+ }
+
+ return packets_dropped;
+}
+
+static void xensock_poll(long unsigned int data)
+{
+ struct sockfront_info *np = (struct sockfront_info *)data;
+ struct xen_sock_dev *dev = np->sockdev;
+ struct sk_buff *skb;
+ struct sockfront_rx_info rinfo;
+ struct xen_sockif_rx_response *rx = &rinfo.rx;
+ RING_IDX i, rp;
+ int work_done;
+ struct sk_buff_head rxq;
+ struct sk_buff_head errq;
+ struct sk_buff_head tmpq;
+ unsigned long flags;
+ int err;
+ int budget = 16;
+ int more_to_do = 1;
+
+ spin_lock(&np->rx_lock);
+
+ skb_queue_head_init(&rxq);
+ skb_queue_head_init(&errq);
+ skb_queue_head_init(&tmpq);
+
+ rp = np->rx.sring->rsp_prod;
+ rmb(); /* Ensure we see queued responses up to 'rp'. */
+
+ i = np->rx.rsp_cons;
+ work_done = 0;
+ while ((i != rp) && (work_done < budget)) {
+ memcpy(rx, RING_GET_RESPONSE(&np->rx, i), sizeof(*rx));
+
+ err = xensock_get_responses(np, &rinfo, rp, &tmpq);
+
+ if (unlikely(err)) {
+ while ((skb = __skb_dequeue(&tmpq)))
+ __skb_queue_tail(&errq, skb);
+ i = np->rx.rsp_cons;
+ continue;
+ }
+
+ skb = __skb_dequeue(&tmpq);
+
+ SOCKFRONT_SKB_CB(skb)->pull_to = rx->status;
+ if (SOCKFRONT_SKB_CB(skb)->pull_to > RX_COPY_THRESHOLD)
+ SOCKFRONT_SKB_CB(skb)->pull_to = RX_COPY_THRESHOLD;
+
+ skb_shinfo(skb)->frags[0].page_offset = rx->offset;
+ skb_frag_size_set(&skb_shinfo(skb)->frags[0], rx->status);
+ skb->data_len = rx->status;
+
+ i = xensock_fill_frags(np, skb, &tmpq);
+
+ /* Truesize is the actual allocation size, even if the
+ * allocation is only partially used.
+ */
+ skb->truesize += PAGE_SIZE * skb_shinfo(skb)->nr_frags;
+ skb->len += skb->data_len;
+
+ __skb_queue_tail(&rxq, skb);
+
+ np->rx.rsp_cons = ++i;
+ work_done++;
+ }
+
+ __skb_queue_purge(&errq);
+
+ work_done -= handle_incoming_queue(dev, &rxq);
+
+ /* If we get a callback with very few responses, reduce fill target. */
+ /* NB. Note exponential increase, linear decrease. */
+ if (((np->rx.req_prod_pvt - np->rx.sring->rsp_prod) >
+ ((3*np->rx_target) / 4)) &&
+ (--np->rx_target < np->rx_min_target))
+ np->rx_target = np->rx_min_target;
+
+ xensock_alloc_rx_buffers(dev);
+
+ if (work_done < budget) {
+ local_irq_save(flags);
+
+ RING_FINAL_CHECK_FOR_RESPONSES(&np->rx, more_to_do);
+
+ local_irq_restore(flags);
+ }
+
+ spin_unlock(&np->rx_lock);
+ if (more_to_do)
+ tasklet_schedule(&np->rx_poll);
+}
+
+static void xensock_release_tx_bufs(struct sockfront_info *np)
+{
+ struct sk_buff *skb;
+ int i;
+
+ for (i = 0; i < SOCK_TX_RING_SIZE; i++) {
+ /* Skip over entries which are actually freelist references */
+ if (skb_entry_is_link(&np->tx_skbs[i]))
+ continue;
+
+ skb = np->tx_skbs[i].skb;
+ gnttab_end_foreign_access_ref(np->grant_tx_ref[i],
+ GNTMAP_readonly);
+ gnttab_release_grant_reference(&np->gref_tx_head,
+ np->grant_tx_ref[i]);
+ np->grant_tx_ref[i] = GRANT_INVALID_REF;
+ add_id_to_freelist(&np->tx_skb_freelist, np->tx_skbs, i);
+ dev_kfree_skb_irq(skb);
+ }
+}
+
+static void xensock_release_rx_bufs(struct sockfront_info *np)
+{
+ struct mmu_update *mmu = np->rx_mmu;
+ struct multicall_entry *mcl = np->rx_mcl;
+ struct sk_buff_head free_list;
+ struct sk_buff *skb;
+ unsigned long mfn;
+ int xfer = 0, noxfer = 0, unused = 0;
+ int id, ref;
+
+ dev_warn(&np->xbdev->dev, "%s: fix me for copying receiver.\n",
+ __func__);
+ return;
+
+ skb_queue_head_init(&free_list);
+
+ spin_lock_bh(&np->rx_lock);
+
+ for (id = 0; id < SOCK_RX_RING_SIZE; id++) {
+ ref = np->grant_rx_ref[id];
+ if (ref == GRANT_INVALID_REF) {
+ unused++;
+ continue;
+ }
+
+ skb = np->rx_skbs[id];
+ mfn = gnttab_end_foreign_transfer_ref(ref);
+ gnttab_release_grant_reference(&np->gref_rx_head, ref);
+ np->grant_rx_ref[id] = GRANT_INVALID_REF;
+
+ if (0 == mfn) {
+ skb_shinfo(skb)->nr_frags = 0;
+ dev_kfree_skb(skb);
+ noxfer++;
+ continue;
+ }
+
+ if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+ /* Remap the page. */
+ const struct page *page =
+ skb_frag_page(&skb_shinfo(skb)->frags[0]);
+ unsigned long pfn = page_to_pfn(page);
+ void *vaddr = page_address(page);
+
+ MULTI_update_va_mapping(mcl, (unsigned long)vaddr,
+ mfn_pte(mfn, PAGE_KERNEL),
+ 0);
+ mcl++;
+ mmu->ptr = ((u64)mfn << PAGE_SHIFT)
+ | MMU_MACHPHYS_UPDATE;
+ mmu->val = pfn;
+ mmu++;
+
+ set_phys_to_machine(pfn, mfn);
+ }
+ __skb_queue_tail(&free_list, skb);
+ xfer++;
+ }
+
+ dev_info(&np->xbdev->dev, "%s: %d xfer, %d noxfer, %d unused\n",
+ __func__, xfer, noxfer, unused);
+
+ if (xfer) {
+ if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+ /* Do all the remapping work and M2P updates. */
+ MULTI_mmu_update(mcl, np->rx_mmu, mmu - np->rx_mmu,
+ NULL, DOMID_SELF);
+ mcl++;
+ HYPERVISOR_multicall(np->rx_mcl, mcl - np->rx_mcl);
+ }
+ }
+
+ __skb_queue_purge(&free_list);
+
+ spin_unlock_bh(&np->rx_lock);
+}
+
+static void xensock_uninit(struct xen_sock_dev *dev)
+{
+ struct sockfront_info *np = xensock_dev_priv(dev);
+
+ xensock_release_tx_bufs(np);
+ xensock_release_rx_bufs(np);
+ gnttab_free_grant_references(np->gref_tx_head);
+ gnttab_free_grant_references(np->gref_rx_head);
+}
+
+static irqreturn_t xensock_interrupt(int irq, void *dev_id)
+{
+ struct xen_sock_dev *dev = dev_id;
+ struct sockfront_info *np = xensock_dev_priv(dev);
+ unsigned long flags;
+
+ spin_lock_irqsave(&np->tx_lock, flags);
+
+ if (likely(sockif_carrier_ok(dev))) {
+ xensock_tx_buf_gc(dev);
+ /* Under tx_lock: protects access to rx shared-ring indexes. */
+ if (RING_HAS_UNCONSUMED_RESPONSES(&np->rx))
+ tasklet_schedule(&np->rx_poll);
+ }
+
+ spin_unlock_irqrestore(&np->tx_lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static struct xen_sock_dev *xensock_create_dev(struct xenbus_device *dev)
+{
+ int i, err;
+ struct xen_sock_dev *sockdev;
+ struct sockfront_info *np;
+
+ sockdev = alloc_xen_sock_dev(sizeof(struct sockfront_info), "vsock");
+ if (!sockdev)
+ return ERR_PTR(-ENOMEM);
+
+ np = xensock_dev_priv(sockdev);
+ np->xbdev = dev;
+
+ spin_lock_init(&np->tx_lock);
+ spin_lock_init(&np->rx_lock);
+
+ skb_queue_head_init(&np->rx_batch);
+ np->rx_target = RX_DFL_MIN_TARGET;
+ np->rx_min_target = RX_DFL_MIN_TARGET;
+ np->rx_max_target = RX_MAX_TARGET;
+
+ init_timer(&np->rx_refill_timer);
+ np->rx_refill_timer.data = (unsigned long)sockdev;
+ np->rx_refill_timer.function = rx_refill_timeout;
+
+ /* Initialise tx_skbs as a free chain containing every entry. */
+ np->tx_skb_freelist = 0;
+ for (i = 0; i < SOCK_TX_RING_SIZE; i++) {
+ skb_entry_set_link(&np->tx_skbs[i], i+1);
+ np->grant_tx_ref[i] = GRANT_INVALID_REF;
+ }
+
+ /* Clear out rx_skbs */
+ for (i = 0; i < SOCK_RX_RING_SIZE; i++) {
+ np->rx_skbs[i] = NULL;
+ np->grant_rx_ref[i] = GRANT_INVALID_REF;
+ }
+
+ /* A grant for every tx ring slot */
+ if (gnttab_alloc_grant_references(TX_MAX_TARGET,
+ &np->gref_tx_head) < 0) {
+ pr_alert("#### sockfront can't alloc tx grant refs\n");
+ err = -ENOMEM;
+ goto exit;
+ }
+ /* A grant for every rx ring slot */
+ if (gnttab_alloc_grant_references(RX_MAX_TARGET,
+ &np->gref_rx_head) < 0) {
+ pr_alert("#### sockfront can't alloc rx grant refs\n");
+ err = -ENOMEM;
+ goto exit_free_tx;
+ }
+
+ tasklet_init(&np->rx_poll, xensock_poll, (unsigned long)np);
+
+ sockdev->start_xmit = xensock_start_xmit;
+
+ np->sockdev = sockdev;
+
+ sockif_carrier_off(sockdev);
+
+ return sockdev;
+
+ exit_free_tx:
+ gnttab_free_grant_references(np->gref_tx_head);
+ exit:
+ free_xen_sock_dev(sockdev);
+ return ERR_PTR(err);
+}
+
+static void xensock_end_access(int ref, void *page)
+{
+ /* This frees the page as a side-effect */
+ if (ref != GRANT_INVALID_REF)
+ gnttab_end_foreign_access(ref, 0, (unsigned long)page);
+}
+
+static void xensock_disconnect_backend(struct sockfront_info *info)
+{
+ /* Stop old i/f to prevent errors whilst we rebuild the state. */
+ spin_lock_bh(&info->rx_lock);
+ spin_lock_irq(&info->tx_lock);
+ sockif_carrier_off(info->sockdev);
+ spin_unlock_irq(&info->tx_lock);
+ spin_unlock_bh(&info->rx_lock);
+
+ if (info->irq)
+ unbind_from_irqhandler(info->irq, info);
+ info->evtchn = 0;
+ info->irq = 0;
+
+ /* End access and free the pages */
+ xensock_end_access(info->tx_ring_ref, info->tx.sring);
+ xensock_end_access(info->rx_ring_ref, info->rx.sring);
+
+ info->tx_ring_ref = GRANT_INVALID_REF;
+ info->rx_ring_ref = GRANT_INVALID_REF;
+ info->tx.sring = NULL;
+ info->rx.sring = NULL;
+}
+
+static int setup_sockfront(struct xenbus_device *dev,
+ struct sockfront_info *info)
+{
+ struct xen_sockif_tx_sring *txs;
+ struct xen_sockif_rx_sring *rxs;
+ int err;
+
+ info->tx_ring_ref = GRANT_INVALID_REF;
+ info->rx_ring_ref = GRANT_INVALID_REF;
+ info->rx.sring = NULL;
+ info->tx.sring = NULL;
+ info->irq = 0;
+
+ txs = (struct xen_sockif_tx_sring *)get_zeroed_page(GFP_NOIO |
+ __GFP_HIGH);
+ if (!txs) {
+ err = -ENOMEM;
+ xenbus_dev_fatal(dev, err, "allocating tx ring page");
+ goto fail;
+ }
+ SHARED_RING_INIT(txs);
+ FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE);
+
+ err = xenbus_grant_ring(dev, virt_to_mfn(txs));
+ if (err < 0) {
+ free_page((unsigned long)txs);
+ goto fail;
+ }
+
+ info->tx_ring_ref = err;
+ rxs = (struct xen_sockif_rx_sring *)get_zeroed_page(GFP_NOIO |
+ __GFP_HIGH);
+ if (!rxs) {
+ err = -ENOMEM;
+ xenbus_dev_fatal(dev, err, "allocating rx ring page");
+ goto fail;
+ }
+ SHARED_RING_INIT(rxs);
+ FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE);
+
+ err = xenbus_grant_ring(dev, virt_to_mfn(rxs));
+ if (err < 0) {
+ free_page((unsigned long)rxs);
+ goto fail;
+ }
+ info->rx_ring_ref = err;
+
+ err = xenbus_alloc_evtchn(dev, &info->evtchn);
+ if (err)
+ goto fail;
+
+ err = bind_evtchn_to_irqhandler(info->evtchn, xensock_interrupt,
+ 0, "sockif", info->sockdev);
+ if (err < 0)
+ goto fail;
+ info->irq = err;
+ return 0;
+
+ fail:
+ return err;
+}
+
+/* Common code used when first setting up, and when resuming. */
+static int talk_to_sockback(struct xenbus_device *dev,
+ struct sockfront_info *info)
+{
+ const char *message;
+ struct xenbus_transaction xbt;
+ int err;
+
+ /* Create shared ring, alloc event channel. */
+ err = setup_sockfront(dev, info);
+ if (err)
+ goto out;
+
+again:
+ err = xenbus_transaction_start(&xbt);
+ if (err) {
+ xenbus_dev_fatal(dev, err, "starting transaction");
+ goto destroy_ring;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u",
+ info->tx_ring_ref);
+ if (err) {
+ message = "writing tx ring-ref";
+ goto abort_transaction;
+ }
+ err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u",
+ info->rx_ring_ref);
+ if (err) {
+ message = "writing rx ring-ref";
+ goto abort_transaction;
+ }
+ err = xenbus_printf(xbt, dev->nodename,
+ "event-channel", "%u", info->evtchn);
+ if (err) {
+ message = "writing event-channel";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "request-rx-copy", "%u",
+ 1);
+ if (err) {
+ message = "writing request-rx-copy";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "feature-rx-notify", "%d", 1);
+ if (err) {
+ message = "writing feature-rx-notify";
+ goto abort_transaction;
+ }
+
+ err = xenbus_transaction_end(xbt, 0);
+ if (err) {
+ if (err == -EAGAIN)
+ goto again;
+ xenbus_dev_fatal(dev, err, "completing transaction");
+ goto destroy_ring;
+ }
+
+ xenbus_switch_state(dev, XenbusStateInitialised);
+ return 0;
+
+ abort_transaction:
+ xenbus_transaction_end(xbt, 1);
+ xenbus_dev_fatal(dev, err, "%s", message);
+ destroy_ring:
+ xensock_disconnect_backend(info);
+ out:
+ return err;
+}
+
+/**
+ * We are reconnecting to the backend, due to a suspend/resume, or a backend
+ * driver restart. We tear down our sockif structure and recreate it, but
+ * leave the device-layer structures intact so that this is transparent to the
+ * rest of the kernel.
+ */
+static int sockfront_resume(struct xenbus_device *dev)
+{
+ struct sockfront_info *info = dev_get_drvdata(&dev->dev);
+
+ dev_dbg(&dev->dev, "%s\n", dev->nodename);
+
+ xensock_disconnect_backend(info);
+ return talk_to_sockback(info->xbdev, info);
+}
+
+/**
+ * Entry point to this code when a new device is created. Allocate the basic
+ * structures and the ring buffers for communication with the backend, and
+ * inform the backend of the appropriate details for those.
+ */
+static int sockfront_probe(struct xenbus_device *dev,
+ const struct xenbus_device_id *id)
+{
+ int err;
+ struct xen_sock_dev *sockdev;
+ struct sockfront_info *info;
+
+ sockdev = xensock_create_dev(dev);
+ if (IS_ERR(sockdev)) {
+ err = PTR_ERR(sockdev);
+ xenbus_dev_fatal(dev, err, "creating sockdev");
+ return err;
+ }
+
+ info = xensock_dev_priv(sockdev);
+ dev_set_drvdata(&dev->dev, info);
+
+ err = xensock_register_dev(info->sockdev);
+ if (err) {
+ pr_warn("%s: xensock_register_dev err=%d\n",
+ __func__, err);
+ goto fail;
+ }
+
+ err = talk_to_sockback(info->xbdev, info);
+ if (err)
+ goto fail;
+
+ return 0;
+
+ fail:
+ free_xen_sock_dev(sockdev);
+ dev_set_drvdata(&dev->dev, NULL);
+ return err;
+}
+
+static int xensock_connect(struct xen_sock_dev *dev)
+{
+ struct sockfront_info *np = xensock_dev_priv(dev);
+ int i, requeue_idx, err;
+ struct sk_buff *skb;
+ grant_ref_t ref;
+ struct xen_sockif_rx_request *req;
+ unsigned int feature_rx_copy;
+
+ err = xenbus_scanf(XBT_NIL, np->xbdev->otherend,
+ "feature-rx-copy", "%u", &feature_rx_copy);
+ if (err != 1)
+ feature_rx_copy = 0;
+
+ if (!feature_rx_copy) {
+ dev_info(&np->xbdev->dev,
+ "backend does not support copying receive path\n");
+ return -ENODEV;
+ }
+
+ spin_lock_bh(&np->rx_lock);
+ spin_lock_irq(&np->tx_lock);
+
+ /* Step 1: Discard all pending TX packet fragments. */
+ xensock_release_tx_bufs(np);
+
+ /* Step 2: Rebuild the RX buffer freelist and the RX ring itself. */
+ for (requeue_idx = 0, i = 0; i < SOCK_RX_RING_SIZE; i++) {
+ skb_frag_t *frag;
+ const struct page *page;
+
+ if (!np->rx_skbs[i])
+ continue;
+
+ skb = xensock_get_rx_skb(np, i);
+ np->rx_skbs[requeue_idx] = skb;
+ ref = xensock_get_rx_ref(np, i);
+ np->grant_rx_ref[requeue_idx] = ref;
+ req = RING_GET_REQUEST(&np->rx, requeue_idx);
+
+ frag = &skb_shinfo(skb)->frags[0];
+ page = skb_frag_page(frag);
+ gnttab_grant_foreign_access_ref(
+ ref, np->xbdev->otherend_id,
+ pfn_to_mfn(page_to_pfn(page)),
+ 0);
+ req->gref = ref;
+ req->id = requeue_idx;
+
+ requeue_idx++;
+ }
+
+ np->rx.req_prod_pvt = requeue_idx;
+
+ /* Step 3: All public and private state should now be sane. Get
+ * ready to start sending and receiving packets and give the driver
+ * domain a kick because we've probably just requeued some
+ * packets.
+ */
+ sockif_carrier_on(np->sockdev);
+ notify_remote_via_irq(np->irq);
+ xensock_tx_buf_gc(dev);
+ xensock_alloc_rx_buffers(dev);
+
+ spin_unlock_irq(&np->tx_lock);
+ spin_unlock_bh(&np->rx_lock);
+
+ return 0;
+}
+
+/**
+ * Callback received when the backend's state changes.
+ */
+static void sockback_changed(struct xenbus_device *dev,
+ enum xenbus_state backend_state)
+{
+ struct sockfront_info *np = dev_get_drvdata(&dev->dev);
+ struct xen_sock_dev *sockdev = np->sockdev;
+
+ dev_dbg(&dev->dev, "sockfront:sndback_changed to state %s\n",
+ xenbus_strstate(backend_state));
+
+ switch (backend_state) {
+ case XenbusStateInitialising:
+ case XenbusStateInitWait:
+ case XenbusStateInitialised:
+ case XenbusStateReconfiguring:
+ case XenbusStateReconfigured:
+ case XenbusStateUnknown:
+ case XenbusStateClosed:
+ break;
+
+ case XenbusStateConnected:
+ if (xensock_connect(sockdev) != 0)
+ break;
+ xenbus_switch_state(dev, XenbusStateConnected);
+ break;
+
+ case XenbusStateClosing:
+ xenbus_frontend_closed(dev);
+ break;
+ }
+}
+
+static const struct xenbus_device_id sockfront_ids[] = {
+ { "vsock" },
+ { "" }
+};
+
+
+static int sockfront_remove(struct xenbus_device *dev)
+{
+ struct sockfront_info *info = dev_get_drvdata(&dev->dev);
+
+ dev_dbg(&dev->dev, "%s\n", dev->nodename);
+
+ xensock_disconnect_backend(info);
+
+ xensock_unregister_dev(info->sockdev);
+
+ tasklet_disable(&info->rx_poll);
+ tasklet_kill(&info->rx_poll);
+ xensock_uninit(info->sockdev);
+
+ del_timer_sync(&info->rx_refill_timer);
+
+ free_xen_sock_dev(info->sockdev);
+
+ return 0;
+}
+
+static DEFINE_XENBUS_DRIVER(sockfront, ,
+ .probe = sockfront_probe,
+ .remove = sockfront_remove,
+ .resume = sockfront_resume,
+ .otherend_changed = sockback_changed,
+);
+
+static int __init sockif_init(void)
+{
+ int ret;
+
+ /*FIXME: xen_pv_domain() should be here, but ARM hardcoded to hvm*/
+ if (!xen_domain())
+ return -ENODEV;
+
+ /* Nothing to do if running in dom0. */
+ if (xen_initial_domain())
+ return -ENODEV;
+
+ pr_info("Initialising Xen socket driver.\n");
+
+ ret = xenbus_register_frontend(&sockfront_driver);
+ if (ret < 0)
+ return ret;
+
+ ret = xensock_proto_client_init();
+ if (ret)
+ goto err_unregister_frontend;
+
+ return ret;
+
+err_unregister_frontend:
+ xenbus_unregister_driver(&sockfront_driver);
+ return ret;
+}
+module_init(sockif_init);
+
+
+static void __exit sockif_exit(void)
+{
+ xensock_proto_cleanup();
+ xenbus_unregister_driver(&sockfront_driver);
+}
+module_exit(sockif_exit);
+
+MODULE_DESCRIPTION("Xensock device frontend");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("xen:xensock");
--
1.8.2.rc2
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers
2014-08-08 11:32 [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers Oleksandr Dmytryshyn
` (2 preceding siblings ...)
2014-08-08 11:32 ` [PATCH 3/3] xen-sockfront: add support of the xen-sockfront driver Oleksandr Dmytryshyn
@ 2014-08-08 12:36 ` David Vrabel
2014-08-08 14:41 ` Stefano Stabellini
2014-08-11 9:40 ` Vitaly V. Ch
2014-08-08 15:27 ` Wei Liu
2014-08-11 12:58 ` David Vrabel
5 siblings, 2 replies; 12+ messages in thread
From: David Vrabel @ 2014-08-08 12:36 UTC (permalink / raw)
To: Oleksandr Dmytryshyn, Ian Campbell, Stefano Stabellini,
Tim Deegan, xen-devel
On 08/08/14 12:32, Oleksandr Dmytryshyn wrote:
> Next series of the patches adds new socket support: xensock.
> Those sockets will be used for the xen-sock frontend/backend
> drivers. Those drivers will allow to connect via xensock
> sockets (in this case dom0/domD sockets can be used for the
> server application and domU sockets can be used for the
> client application). Those sockets are similar to the TCP sockets.
> But there are some limitations. Xensock sockets
> ignore an address and can act only as the stream
> sockets. Only one xensock socket can be opened in the frontend
> side and it will be connected with the single xensock socket
> in the backend side (this link is created automatically by
> frontend and backend driver).
You should look at using AF_VSOCK sockets instead.
David
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers
2014-08-08 12:36 ` [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers David Vrabel
@ 2014-08-08 14:41 ` Stefano Stabellini
2014-08-20 17:58 ` Ian Campbell
2014-08-11 9:40 ` Vitaly V. Ch
1 sibling, 1 reply; 12+ messages in thread
From: Stefano Stabellini @ 2014-08-08 14:41 UTC (permalink / raw)
To: David Vrabel
Cc: Tim Deegan, Oleksandr Dmytryshyn, Stefano Stabellini,
Ian Campbell, xen-devel
On Fri, 8 Aug 2014, David Vrabel wrote:
> On 08/08/14 12:32, Oleksandr Dmytryshyn wrote:
> > Next series of the patches adds new socket support: xensock.
> > Those sockets will be used for the xen-sock frontend/backend
> > drivers. Those drivers will allow to connect via xensock
> > sockets (in this case dom0/domD sockets can be used for the
> > server application and domU sockets can be used for the
> > client application). Those sockets are similar to the TCP sockets.
> > But there are some limitations. Xensock sockets
> > ignore an address and can act only as the stream
> > sockets. Only one xensock socket can be opened in the frontend
> > side and it will be connected with the single xensock socket
> > in the backend side (this link is created automatically by
> > frontend and backend driver).
>
> You should look at using AF_VSOCK sockets instead.
Even if he uses AF_VSOCK instead of introducing AF_XENSOCK, he would
still need to add a new Xen specific frontend and backend pair, right?
I am in favor of this work, but you would need to spend a few words in
the patch description to explain why libvchan doesn't fit your needs.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers
2014-08-08 14:41 ` Stefano Stabellini
@ 2014-08-20 17:58 ` Ian Campbell
0 siblings, 0 replies; 12+ messages in thread
From: Ian Campbell @ 2014-08-20 17:58 UTC (permalink / raw)
To: Stefano Stabellini
Cc: Tim Deegan, Oleksandr Dmytryshyn, Stefano Stabellini,
David Vrabel, xen-devel
On Fri, 2014-08-08 at 15:41 +0100, Stefano Stabellini wrote:
> On Fri, 8 Aug 2014, David Vrabel wrote:
> > On 08/08/14 12:32, Oleksandr Dmytryshyn wrote:
> > > Next series of the patches adds new socket support: xensock.
> > > Those sockets will be used for the xen-sock frontend/backend
> > > drivers. Those drivers will allow to connect via xensock
> > > sockets (in this case dom0/domD sockets can be used for the
> > > server application and domU sockets can be used for the
> > > client application). Those sockets are similar to the TCP sockets.
> > > But there are some limitations. Xensock sockets
> > > ignore an address and can act only as the stream
> > > sockets. Only one xensock socket can be opened in the frontend
> > > side and it will be connected with the single xensock socket
> > > in the backend side (this link is created automatically by
> > > frontend and backend driver).
> >
> > You should look at using AF_VSOCK sockets instead.
>
> Even if he uses AF_VSOCK instead of introducing AF_XENSOCK, he would
> still need to add a new Xen specific frontend and backend pair, right?
>
> I am in favor of this work, but you would need to spend a few words in
> the patch description to explain why libvchan doesn't fit your needs.
Agreed.
It would be nice (tm) to have an in kernel implementation of the vchan
code so that a userprocess in one domain and kernel code in another
could interact over vchan (I can't remember who but someone needed
something like that), but I guess this is somewhat orthogonal to this
series.
Ian.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers
2014-08-08 12:36 ` [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers David Vrabel
2014-08-08 14:41 ` Stefano Stabellini
@ 2014-08-11 9:40 ` Vitaly V. Ch
2014-08-11 9:50 ` Vitaly V. Ch
1 sibling, 1 reply; 12+ messages in thread
From: Vitaly V. Ch @ 2014-08-11 9:40 UTC (permalink / raw)
To: David Vrabel
Cc: Tim Deegan, Oleksandr Dmytryshyn, Stefano Stabellini,
Ian Campbell, xen-devel
[-- Attachment #1.1: Type: text/plain, Size: 1277 bytes --]
On Fri, Aug 8, 2014 at 3:36 PM, David Vrabel <david.vrabel@citrix.com>
wrote:
> On 08/08/14 12:32, Oleksandr Dmytryshyn wrote:
> > Next series of the patches adds new socket support: xensock.
> > Those sockets will be used for the xen-sock frontend/backend
> > drivers. Those drivers will allow to connect via xensock
> > sockets (in this case dom0/domD sockets can be used for the
> > server application and domU sockets can be used for the
> > client application). Those sockets are similar to the TCP sockets.
> > But there are some limitations. Xensock sockets
> > ignore an address and can act only as the stream
> > sockets. Only one xensock socket can be opened in the frontend
> > side and it will be connected with the single xensock socket
> > in the backend side (this link is created automatically by
> > frontend and backend driver).
>
> You should look at using AF_VSOCK sockets instead.
>
But in this situation he will need to introduce new protocol in that
domain. Do you sure than new protocol is better than new domain? Also does
anybody use AF_VSOCK outside vmware?
With best regards,
Vitaly Chernooky
>
> David
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel
>
[-- Attachment #1.2: Type: text/html, Size: 2139 bytes --]
[-- Attachment #2: Type: text/plain, Size: 126 bytes --]
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers
2014-08-11 9:40 ` Vitaly V. Ch
@ 2014-08-11 9:50 ` Vitaly V. Ch
0 siblings, 0 replies; 12+ messages in thread
From: Vitaly V. Ch @ 2014-08-11 9:50 UTC (permalink / raw)
To: David Vrabel
Cc: Tim Deegan, Oleksandr Dmytryshyn, Stefano Stabellini,
Ian Campbell, xen-devel
[-- Attachment #1.1: Type: text/plain, Size: 1553 bytes --]
On Mon, Aug 11, 2014 at 12:40 PM, Vitaly V. Ch <vitaly.v.ch@chernooky.com>
wrote:
>
>
>
> On Fri, Aug 8, 2014 at 3:36 PM, David Vrabel <david.vrabel@citrix.com>
> wrote:
>
>> On 08/08/14 12:32, Oleksandr Dmytryshyn wrote:
>> > Next series of the patches adds new socket support: xensock.
>> > Those sockets will be used for the xen-sock frontend/backend
>> > drivers. Those drivers will allow to connect via xensock
>> > sockets (in this case dom0/domD sockets can be used for the
>> > server application and domU sockets can be used for the
>> > client application). Those sockets are similar to the TCP sockets.
>> > But there are some limitations. Xensock sockets
>> > ignore an address and can act only as the stream
>> > sockets. Only one xensock socket can be opened in the frontend
>> > side and it will be connected with the single xensock socket
>> > in the backend side (this link is created automatically by
>> > frontend and backend driver).
>>
>> You should look at using AF_VSOCK sockets instead.
>>
>
> But in this situation he will need to introduce new protocol in that
> domain. Do you sure than new protocol is better than new domain? Also does
> anybody use AF_VSOCK outside vmware?
>
Also in kernel version where Alexander introduce AF_XENSOCK nothing from
AF_VSOCK is present.
With best regards,
Vitaly Chernooky
>
> With best regards,
>
> Vitaly Chernooky
>
>
>>
>> David
>>
>>
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@lists.xen.org
>> http://lists.xen.org/xen-devel
>>
>
>
[-- Attachment #1.2: Type: text/html, Size: 2981 bytes --]
[-- Attachment #2: Type: text/plain, Size: 126 bytes --]
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers
2014-08-08 11:32 [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers Oleksandr Dmytryshyn
` (3 preceding siblings ...)
2014-08-08 12:36 ` [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers David Vrabel
@ 2014-08-08 15:27 ` Wei Liu
2014-08-11 9:28 ` Oleksandr Dmytryshyn
2014-08-11 12:58 ` David Vrabel
5 siblings, 1 reply; 12+ messages in thread
From: Wei Liu @ 2014-08-08 15:27 UTC (permalink / raw)
To: Oleksandr Dmytryshyn
Cc: Tim Deegan, wei.liu2, Stefano Stabellini, Ian Campbell, xen-devel
Yes you've hooked it up to socket layer but for large part it's
duplication of old (and possible buggy) code -- 3.10 netfront/back.
I think you should first state why this new driver is needed. You will
also need to refactor your code, so that it depends on xen-netback /
front. Code duplication like this is not acceptable upstream.
Wei.
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers
2014-08-08 15:27 ` Wei Liu
@ 2014-08-11 9:28 ` Oleksandr Dmytryshyn
0 siblings, 0 replies; 12+ messages in thread
From: Oleksandr Dmytryshyn @ 2014-08-11 9:28 UTC (permalink / raw)
To: Wei Liu; +Cc: Tim Deegan, Stefano Stabellini, Ian Campbell, xen-devel
My drivers provide a large bandwidth and minimal latency with small
packets. In case the PV Net there is an TCP-specific protocol
overhead.
Oleksandr Dmytryshyn | Product Engineering and Development
GlobalLogic
M +38.067.382.2525
www.globallogic.com
http://www.globallogic.com/email_disclaimer.txt
On Fri, Aug 8, 2014 at 6:27 PM, Wei Liu <wei.liu2@citrix.com> wrote:
> Yes you've hooked it up to socket layer but for large part it's
> duplication of old (and possible buggy) code -- 3.10 netfront/back.
>
> I think you should first state why this new driver is needed. You will
> also need to refactor your code, so that it depends on xen-netback /
> front. Code duplication like this is not acceptable upstream.
>
> Wei.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers
2014-08-08 11:32 [PATCH 0/3] Introduce xensock socket and implement sockback and sockfront drivers Oleksandr Dmytryshyn
` (4 preceding siblings ...)
2014-08-08 15:27 ` Wei Liu
@ 2014-08-11 12:58 ` David Vrabel
5 siblings, 0 replies; 12+ messages in thread
From: David Vrabel @ 2014-08-11 12:58 UTC (permalink / raw)
To: Oleksandr Dmytryshyn, Ian Campbell, Stefano Stabellini,
Tim Deegan, xen-devel
On 08/08/14 12:32, Oleksandr Dmytryshyn wrote:
> Next series of the patches adds new socket support: xensock.
> Those sockets will be used for the xen-sock frontend/backend
> drivers. Those drivers will allow to connect via xensock
> sockets (in this case dom0/domD sockets can be used for the
> server application and domU sockets can be used for the
> client application). Those sockets are similar to the TCP sockets.
> But there are some limitations. Xensock sockets
> ignore an address and can act only as the stream
> sockets. Only one xensock socket can be opened in the frontend
> side and it will be connected with the single xensock socket
> in the backend side (this link is created automatically by
> frontend and backend driver).
We only want one generic socket-based interdomain communication
mechanism in the kernel and this proposal is lacking in several areas.
* It does not use the existing support for interdomain sockets (AF_VSOCK).
* It it not suitable for a channel between two mutually untrusting peers.
* The single channel to one other domain is insufficient. Each domain
must be able to support connections to many other domains.
See also a previous discussion.
http://lists.xen.org/archives/html/xen-devel/2013-06/msg01123.html
But note the document has not been updated following the feedback from
that thread.
There is a userspace prototype available:
http://xenbits.xen.org/gitweb/?p=people/dvrabel/idc-prototype.git;a=summary
David
^ permalink raw reply [flat|nested] 12+ messages in thread