* Re: [PATCH] Fix Warnings from net/netlink/genetlink.c
From: Stephen Rothwell @ 2009-08-12 3:50 UTC (permalink / raw)
To: Stephen Hemminger
Cc: Marcel Holtmann, vibi_sreenivasan, netdev, Johannes Berg,
Thomas Graf, linux-next
In-Reply-To: <20090811202459.7f98e496@nehalam>
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Hi all,
On Tue, 11 Aug 2009 20:24:59 -0700 Stephen Hemminger <shemminger@vyatta.com> wrote:
>
> > > @@ -136,7 +136,7 @@ int genl_register_mc_group(struct genl_family *family,
> > > {
> > > int id;
> > > unsigned long *new_groups;
> > > - int err;
> > > + int err = 0;
> > >
> > > BUG_ON(grp->name[0] == '\0');
> >
> > this looks fishy. How does gcc thinks this variable is uninitialized. If
> > I look at the code in Linus' tree, I don't see it.
>
> Agreed, and the line numbers are off.
In the -next tree, it looks like this:
int genl_register_mc_group(struct genl_family *family,
struct genl_multicast_group *grp)
{
int id;
unsigned long *new_groups;
int err;
BUG_ON(grp->name[0] == '\0');
genl_lock();
/* special-case our own group */
if (grp == ¬ify_grp)
id = GENL_ID_CTRL;
else
id = find_first_zero_bit(mc_groups,
mc_groups_longs * BITS_PER_LONG);
if (id >= mc_groups_longs * BITS_PER_LONG) {
size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long);
if (mc_groups == &mc_group_start) {
new_groups = kzalloc(nlen, GFP_KERNEL);
if (!new_groups) {
err = -ENOMEM;
goto out;
}
mc_groups = new_groups;
*mc_groups = mc_group_start;
} else {
new_groups = krealloc(mc_groups, nlen, GFP_KERNEL);
if (!new_groups) {
err = -ENOMEM;
goto out;
}
mc_groups = new_groups;
mc_groups[mc_groups_longs] = 0;
}
mc_groups_longs++;
}
if (family->netnsok) {
struct net *net;
rcu_read_lock();
for_each_net_rcu(net) {
err = netlink_change_ngroups(net->genl_sock,
mc_groups_longs * BITS_PER_LONG);
if (err) {
rcu_read_unlock();
goto out;
}
}
rcu_read_unlock();
} else {
err = netlink_change_ngroups(init_net.genl_sock,
mc_groups_longs * BITS_PER_LONG);
if (err)
goto out;
}
grp->id = id;
set_bit(id, mc_groups);
list_add_tail(&grp->list, &family->mcast_groups);
grp->family = family;
genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp);
out:
genl_unlock();
return err;
}
so if family->netnsok is true and the for_each_net_rcu loop executes 0
times, err will not be set ... Now, that may not be logically possible,
but I can't tell that from this code.
--
Cheers,
Stephen Rothwell sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/
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^ permalink raw reply
* Re: [PATCH] Fix Warnings from net/netlink/genetlink.c
From: Stephen Hemminger @ 2009-08-12 3:24 UTC (permalink / raw)
To: Marcel Holtmann
Cc: vibi_sreenivasan, netdev, Johannes Berg, Thomas Graf, linux-next
In-Reply-To: <1250035061.30166.42.camel@localhost.localdomain>
On Tue, 11 Aug 2009 16:57:41 -0700
Marcel Holtmann <marcel@holtmann.org> wrote:
> Hi Vibi,
>
> > net/netlink/genetlink.c: In function `genl_register_mc_group':
> > net/netlink/genetlink.c:139: warning: 'err' might be used uninitialized in this function
> >
> > Signed-off-by: vibi sreenivasan <vibi_sreenivasan@cms.com>
> > ---
> > net/netlink/genetlink.c | 2 +-
> > 1 files changed, 1 insertions(+), 1 deletions(-)
> >
> > diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
> > index 575c643..66f6ba0 100644
> > --- a/net/netlink/genetlink.c
> > +++ b/net/netlink/genetlink.c
> > @@ -136,7 +136,7 @@ int genl_register_mc_group(struct genl_family *family,
> > {
> > int id;
> > unsigned long *new_groups;
> > - int err;
> > + int err = 0;
> >
> > BUG_ON(grp->name[0] == '\0');
>
> this looks fishy. How does gcc thinks this variable is uninitialized. If
> I look at the code in Linus' tree, I don't see it.
Agreed, and the line numbers are off.
--
^ permalink raw reply
* Re: [PATCHv2 2/2] vhost_net: a kernel-level virtio server
From: Gregory Haskins @ 2009-08-12 0:06 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: netdev, virtualization, kvm@vger.kernel.org,
linux-kernel@vger.kernel.org, Ingo Molnar, linux-mm,
Andrew Morton, hpa
In-Reply-To: <20090811212802.GC26309@redhat.com>
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Michael S. Tsirkin wrote:
> What it is: vhost net is a character device that can be used to reduce
> the number of system calls involved in virtio networking.
> Existing virtio net code is used in the guest without modification.
>
> There's similarity with vringfd, with some differences and reduced scope
> - uses eventfd for signalling
> - structures can be moved around in memory at any time (good for migration)
> - support memory table and not just an offset (needed for kvm)
>
> common virtio related code has been put in a separate file vhost.c and
> can be made into a separate module if/when more backends appear. I used
> Rusty's lguest.c as the source for developing this part : this supplied
> me with witty comments I wouldn't be able to write myself.
>
> What it is not: vhost net is not a bus, and not a generic new system
> call. No assumptions are made on how guest performs hypercalls.
> Userspace hypervisors are supported as well as kvm.
>
> How it works: Basically, we connect virtio frontend (configured by
> userspace) to a backend. The backend could be a network device, or a
> tun-like device. In this version I only support raw socket as a backend,
> which can be bound to e.g. SR IOV, or to macvlan device. Backend is
> also configured by userspace, including vlan/mac etc.
>
> Status:
> This works for me, and I haven't see any crashes.
> I have not run any benchmarks yet, compared to userspace, I expect to
> see improved latency (as I save up to 4 system calls per packet) but not
> bandwidth/CPU (as TSO and interrupt mitigation are not supported).
>
> Features that I plan to look at in the future:
> - TSO
> - interrupt mitigation
> - zero copy
Only a quick review for now. Will look closer later.
(see inline)
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
>
> v2
> ---
> MAINTAINERS | 10 +
> arch/x86/kvm/Kconfig | 1 +
> drivers/Makefile | 1 +
> drivers/vhost/Kconfig | 11 +
> drivers/vhost/Makefile | 2 +
> drivers/vhost/net.c | 411 +++++++++++++++++++++++++++
> drivers/vhost/vhost.c | 663 ++++++++++++++++++++++++++++++++++++++++++++
> drivers/vhost/vhost.h | 108 +++++++
> include/linux/Kbuild | 1 +
> include/linux/miscdevice.h | 1 +
> include/linux/vhost.h | 100 +++++++
> 11 files changed, 1309 insertions(+), 0 deletions(-)
> create mode 100644 drivers/vhost/Kconfig
> create mode 100644 drivers/vhost/Makefile
> create mode 100644 drivers/vhost/net.c
> create mode 100644 drivers/vhost/vhost.c
> create mode 100644 drivers/vhost/vhost.h
> create mode 100644 include/linux/vhost.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index ebc2691..eb0c1da 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6312,6 +6312,16 @@ S: Maintained
> F: Documentation/filesystems/vfat.txt
> F: fs/fat/
>
> +VIRTIO HOST (VHOST)
> +P: Michael S. Tsirkin
> +M: mst@redhat.com
> +L: kvm@vger.kernel.org
> +L: virtualization@lists.osdl.org
> +L: netdev@vger.kernel.org
> +S: Maintained
> +F: drivers/vhost/
> +F: include/linux/vhost.h
> +
> VIA RHINE NETWORK DRIVER
> P: Roger Luethi
> M: rl@hellgate.ch
> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> index b84e571..94f44d9 100644
> --- a/arch/x86/kvm/Kconfig
> +++ b/arch/x86/kvm/Kconfig
> @@ -64,6 +64,7 @@ config KVM_AMD
>
> # OK, it's a little counter-intuitive to do this, but it puts it neatly under
> # the virtualization menu.
> +source drivers/vhost/Kconfig
> source drivers/lguest/Kconfig
> source drivers/virtio/Kconfig
>
> diff --git a/drivers/Makefile b/drivers/Makefile
> index bc4205d..1551ae1 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -105,6 +105,7 @@ obj-$(CONFIG_HID) += hid/
> obj-$(CONFIG_PPC_PS3) += ps3/
> obj-$(CONFIG_OF) += of/
> obj-$(CONFIG_SSB) += ssb/
> +obj-$(CONFIG_VHOST_NET) += vhost/
> obj-$(CONFIG_VIRTIO) += virtio/
> obj-$(CONFIG_VLYNQ) += vlynq/
> obj-$(CONFIG_STAGING) += staging/
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> new file mode 100644
> index 0000000..d955406
> --- /dev/null
> +++ b/drivers/vhost/Kconfig
> @@ -0,0 +1,11 @@
> +config VHOST_NET
> + tristate "Host kernel accelerator for virtio net"
> + depends on NET && EVENTFD
> + ---help---
> + This kernel module can be loaded in host kernel to accelerate
> + guest networking with virtio_net. Not to be confused with virtio_net
> + module itself which needs to be loaded in guest kernel.
> +
> + To compile this driver as a module, choose M here: the module will
> + be called vhost_net.
> +
> diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile
> new file mode 100644
> index 0000000..72dd020
> --- /dev/null
> +++ b/drivers/vhost/Makefile
> @@ -0,0 +1,2 @@
> +obj-$(CONFIG_VHOST_NET) += vhost_net.o
> +vhost_net-y := vhost.o net.o
> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
> new file mode 100644
> index 0000000..a04ffd0
> --- /dev/null
> +++ b/drivers/vhost/net.c
> @@ -0,0 +1,411 @@
> +/* Copyright (C) 2009 Red Hat, Inc.
> + * Author: Michael S. Tsirkin <mst@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2.
> + *
> + * virtio-net server in host kernel.
> + */
> +
> +#include <linux/eventfd.h>
> +#include <linux/vhost.h>
> +#include <linux/virtio_net.h>
> +#include <linux/mmu_context.h>
> +#include <linux/miscdevice.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/workqueue.h>
> +#include <linux/rcupdate.h>
> +#include <linux/file.h>
> +
> +#include <linux/net.h>
> +#include <linux/if_packet.h>
> +#include <linux/if_arp.h>
> +
> +#include <net/sock.h>
> +
> +#include <asm/mmu_context.h>
> +
> +#include "vhost.h"
> +
> +enum {
> + VHOST_NET_VQ_RX = 0,
> + VHOST_NET_VQ_TX = 1,
> + VHOST_NET_VQ_MAX = 2,
> +};
> +
> +struct vhost_net {
> + struct vhost_dev dev;
> + struct vhost_virtqueue vqs[VHOST_NET_VQ_MAX];
> + /* We use a kind of RCU to access sock pointer.
> + * All readers access it from workqueue,
> + * which makes it possible to flush the workqueue
> + * instead of synchronize_rcu. Therefore readers
> + * do not need rcu_read_lock/rcu_read_unlock.
> + * Writers use device mutex. */
This seems odd. If you have the flush to act as a sync-barrier, why do
you also need rcu_dereference(sock)? At first blush, it seems
gratuitous. Can you talk about this aspect of the design in more detail?
> + struct socket *sock;
> + struct vhost_poll poll[VHOST_NET_VQ_MAX];
> +};
> +
> +static void handle_tx(struct vhost_net *net)
> +{
> + struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX];
> + unsigned head, out, in;
> + struct msghdr msg = {
> + .msg_name = NULL,
> + .msg_namelen = 0,
> + .msg_control = NULL,
> + .msg_controllen = 0,
> + .msg_iov = (struct iovec *)vq->iov + 1,
> + .msg_flags = MSG_DONTWAIT,
> + };
> + size_t len;
> + int err;
> + struct socket *sock = rcu_dereference(net->sock);
> + if (!sock || !sock_writeable(sock->sk))
> + return;
> +
> + use_mm(net->dev.mm);
> + mutex_lock(&vq->mutex);
> + for (;;) {
> + head = vhost_get_vq_desc(&net->dev, vq, vq->iov, &out, &in);
> + if (head == vq->num)
> + break;
> + if (out <= 1 || in) {
> + vq_err(vq, "Unexpected descriptor format for TX: "
> + "out %d, int %d\n", out, in);
> + break;
> + }
> + /* Sanity check */
> + if (vq->iov->iov_len != sizeof(struct virtio_net_hdr)) {
> + vq_err(vq, "Unexpected header len for TX: "
> + "%ld expected %zd\n", vq->iov->iov_len,
> + sizeof(struct virtio_net_hdr));
> + break;
> + }
> + /* Skip header. TODO: support TSO. */
> + msg.msg_iovlen = out - 1;
> + len = iov_length(vq->iov + 1, out - 1);
> + /* TODO: Check specific error and bomb out unless ENOBUFS? */
> + err = sock->ops->sendmsg(NULL, sock, &msg, len);
> + if (err < 0) {
> + vhost_discard_vq_desc(vq);
> + break;
> + }
> + if (err != len)
> + pr_err("Truncated TX packet: "
> + " len %d != %zd\n", err, len);
> + vhost_add_used_and_trigger(vq, head,
> + len + sizeof(struct virtio_net_hdr));
> + }
> +
> + mutex_unlock(&vq->mutex);
> + unuse_mm(net->dev.mm);
> +}
> +
> +static void handle_rx(struct vhost_net *net)
> +{
> + struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
> + unsigned head, out, in;
> + struct msghdr msg = {
> + .msg_name = NULL,
> + .msg_namelen = 0,
> + .msg_control = NULL, /* FIXME: get and handle RX aux data. */
> + .msg_controllen = 0,
> + .msg_iov = vq->iov + 1,
> + .msg_flags = MSG_DONTWAIT,
> + };
> +
> + struct virtio_net_hdr hdr = {
> + .flags = 0,
> + .gso_type = VIRTIO_NET_HDR_GSO_NONE
> + };
> +
> + size_t len;
> + int err;
> + struct socket *sock = rcu_dereference(net->sock);
> + if (!sock || skb_queue_empty(&sock->sk->sk_receive_queue))
> + return;
> +
> + use_mm(net->dev.mm);
> + mutex_lock(&vq->mutex);
> +
> + for (;;) {
> + head = vhost_get_vq_desc(&net->dev, vq, vq->iov, &out, &in);
> + if (head == vq->num)
> + break;
> + if (in <= 1 || out) {
> + vq_err(vq, "Unexpected descriptor format for RX: out %d, int %d\n",
> + out, in);
> + break;
> + }
> + /* Sanity check */
> + if (vq->iov->iov_len != sizeof(struct virtio_net_hdr)) {
> + vq_err(vq, "Unexpected header len for RX: %ld expected %zd\n",
> + vq->iov->iov_len, sizeof(struct virtio_net_hdr));
> + break;
> + }
> + /* Skip header. TODO: support TSO/mergeable rx buffers. */
> + msg.msg_iovlen = in - 1;
> + len = iov_length(vq->iov + 1, in - 1);
> + err = sock->ops->recvmsg(NULL, sock, &msg,
> + len, MSG_DONTWAIT | MSG_TRUNC);
> + /* TODO: Check specific error and bomb out unless EAGAIN? */
> + if (err < 0) {
> + vhost_discard_vq_desc(vq);
> + break;
> + }
> + /* TODO: Should check and handle checksum. */
> + if (err > len) {
> + pr_err("Discarded truncated rx packet: "
> + " len %d > %zd\n", err, len);
> + vhost_discard_vq_desc(vq);
> + continue;
> + }
> + len = err;
> + err = copy_to_user(vq->iov->iov_base, &hdr, sizeof hdr);
> + if (err) {
> + vq_err(vq, "Unable to write vnet_hdr at addr %p: %d\n",
> + vq->iov->iov_base, err);
> + break;
> + }
> + vhost_add_used_and_trigger(vq, head, len + sizeof hdr);
> + }
> +
> + mutex_unlock(&vq->mutex);
> + unuse_mm(net->dev.mm);
> +}
> +
> +static void handle_tx_kick(struct work_struct *work)
> +{
> + struct vhost_virtqueue *vq;
> + struct vhost_net *net;
> + vq = container_of(work, struct vhost_virtqueue, poll.work);
> + net = container_of(vq->dev, struct vhost_net, dev);
> + handle_tx(net);
> +}
> +
> +static void handle_rx_kick(struct work_struct *work)
> +{
> + struct vhost_virtqueue *vq;
> + struct vhost_net *net;
> + vq = container_of(work, struct vhost_virtqueue, poll.work);
> + net = container_of(vq->dev, struct vhost_net, dev);
> + handle_rx(net);
> +}
> +
> +static void handle_tx_net(struct work_struct *work)
> +{
> + struct vhost_net *net;
> + net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_TX].work);
> + handle_tx(net);
> +}
> +
> +static void handle_rx_net(struct work_struct *work)
> +{
> + struct vhost_net *net;
> + net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_RX].work);
> + handle_rx(net);
> +}
> +
> +static int vhost_net_open(struct inode *inode, struct file *f)
> +{
> + struct vhost_net *n = kzalloc(sizeof *n, GFP_KERNEL);
> + int r;
> + if (!n)
> + return -ENOMEM;
> + f->private_data = n;
> + n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick;
> + n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick;
> + r = vhost_dev_init(&n->dev, n->vqs, VHOST_NET_VQ_MAX);
> + if (r < 0) {
> + kfree(n);
> + return r;
> + }
> +
> + vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT);
> + vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN);
> + return 0;
> +}
> +
> +static struct socket *vhost_net_stop(struct vhost_net *n)
> +{
> + struct socket *sock = n->sock;
> + rcu_assign_pointer(n->sock, NULL);
> + if (sock) {
> + vhost_poll_flush(n->poll + VHOST_NET_VQ_TX);
> + vhost_poll_flush(n->poll + VHOST_NET_VQ_RX);
> + }
> + return sock;
> +}
> +
> +static int vhost_net_release(struct inode *inode, struct file *f)
> +{
> + struct vhost_net *n = f->private_data;
> + struct socket *sock;
> +
> + sock = vhost_net_stop(n);
> + vhost_dev_cleanup(&n->dev);
> + if (sock)
> + fput(sock->file);
> + kfree(n);
> + return 0;
> +}
> +
> +static long vhost_net_set_socket(struct vhost_net *n, int fd)
> +{
> + struct {
> + struct sockaddr_ll sa;
> + char buf[MAX_ADDR_LEN];
> + } uaddr;
> + struct socket *sock, *oldsock = NULL;
> + int uaddr_len = sizeof uaddr, r;
> +
> + mutex_lock(&n->dev.mutex);
> + r = vhost_dev_check_owner(&n->dev);
> + if (r)
> + goto done;
> +
> + if (fd == -1) {
> + /* Disconnect from socket and device. */
> + oldsock = vhost_net_stop(n);
> + goto done;
> + }
> +
> + sock = sockfd_lookup(fd, &r);
> + if (!sock) {
> + r = -ENOTSOCK;
> + goto done;
> + }
> +
> + /* Parameter checking */
> + if (sock->sk->sk_type != SOCK_RAW) {
> + r = -ESOCKTNOSUPPORT;
> + goto done;
> + }
> +
> + r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa,
> + &uaddr_len, 0);
> + if (r)
> + goto done;
> +
> + if (uaddr.sa.sll_family != AF_PACKET) {
> + r = -EPFNOSUPPORT;
> + goto done;
> + }
> +
> + /* start polling new socket */
> + if (sock == oldsock)
> + goto done;
> +
> + if (oldsock) {
> + vhost_poll_stop(n->poll + VHOST_NET_VQ_TX);
> + vhost_poll_stop(n->poll + VHOST_NET_VQ_RX);
> + }
> + oldsock = n->sock;
> + rcu_assign_pointer(n->sock, sock);
> + vhost_poll_start(n->poll + VHOST_NET_VQ_TX, sock->file);
> + vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file);
> +done:
> + mutex_unlock(&n->dev.mutex);
> + if (oldsock) {
> + vhost_poll_flush(n->poll + VHOST_NET_VQ_TX);
> + vhost_poll_flush(n->poll + VHOST_NET_VQ_RX);
> + vhost_poll_flush(&n->dev.vqs[VHOST_NET_VQ_TX].poll);
> + vhost_poll_flush(&n->dev.vqs[VHOST_NET_VQ_RX].poll);
> + fput(oldsock->file);
> + }
> + return r;
> +}
> +
> +static long vhost_net_reset_owner(struct vhost_net *n)
> +{
> + struct socket *sock = NULL;
> + long r;
> + mutex_lock(&n->dev.mutex);
> + r = vhost_dev_check_owner(&n->dev);
> + if (r)
> + goto done;
> + sock = vhost_net_stop(n);
> + r = vhost_dev_reset_owner(&n->dev);
> +done:
> + mutex_unlock(&n->dev.mutex);
> + if (sock)
> + fput(sock->file);
> + return r;
> +}
> +
> +static long vhost_net_ioctl(struct file *f, unsigned int ioctl,
> + unsigned long arg)
> +{
> + struct vhost_net *n = f->private_data;
> + void __user *argp = (void __user *)arg;
> + u32 __user *featurep = argp;
> + int __user *fdp = argp;
> + u32 features;
> + int fd, r;
> + switch (ioctl) {
> + case VHOST_NET_SET_SOCKET:
> + r = get_user(fd, fdp);
> + if (r < 0)
> + return r;
> + return vhost_net_set_socket(n, fd);
> + case VHOST_GET_FEATURES:
> + /* No features for now */
> + features = 0;
> + return put_user(features, featurep);
> + case VHOST_ACK_FEATURES:
> + r = get_user(features, featurep);
> + /* No features for now */
> + if (r < 0)
> + return r;
> + if (features)
> + return -EOPNOTSUPP;
> + return 0;
> + case VHOST_RESET_OWNER:
> + return vhost_net_reset_owner(n);
> + default:
> + return vhost_dev_ioctl(&n->dev, ioctl, arg);
> + }
> +}
> +
> +static struct file_operations vhost_net_fops = {
> + .owner = THIS_MODULE,
> + .release = vhost_net_release,
> + .unlocked_ioctl = vhost_net_ioctl,
> + .open = vhost_net_open,
> +};
> +
> +static struct miscdevice vhost_net_misc = {
> + VHOST_NET_MINOR,
> + "vhost-net",
> + &vhost_net_fops,
> +};
> +
> +int vhost_net_init(void)
> +{
> + int r = vhost_init();
> + if (r)
> + goto err_init;
> + r = misc_register(&vhost_net_misc);
> + if (r)
> + goto err_reg;
> + return 0;
> +err_reg:
> + vhost_cleanup();
> +err_init:
> + return r;
> +
> +}
> +module_init(vhost_net_init);
> +
> +void vhost_net_exit(void)
> +{
> + misc_deregister(&vhost_net_misc);
> + vhost_cleanup();
> +}
> +module_exit(vhost_net_exit);
> +
> +MODULE_VERSION("0.0.1");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Michael S. Tsirkin");
> +MODULE_DESCRIPTION("Host kernel accelerator for virtio net");
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> new file mode 100644
> index 0000000..6178ec1
> --- /dev/null
> +++ b/drivers/vhost/vhost.c
> @@ -0,0 +1,663 @@
> +/* Copyright (C) 2009 Red Hat, Inc.
> + * Copyright (C) 2006 Rusty Russell IBM Corporation
> + *
> + * Author: Michael S. Tsirkin <mst@redhat.com>
> + *
> + * Inspiration, some code, and most witty comments come from
> + * Documentation/lguest/lguest.c, by Rusty Russell
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2.
> + *
> + * Generic code for virtio server in host kernel.
> + */
> +
> +#include <linux/eventfd.h>
> +#include <linux/vhost.h>
> +#include <linux/virtio_net.h>
> +#include <linux/mm.h>
> +#include <linux/miscdevice.h>
> +#include <linux/mutex.h>
> +#include <linux/workqueue.h>
> +#include <linux/rcupdate.h>
> +#include <linux/poll.h>
> +#include <linux/file.h>
> +
> +#include <linux/net.h>
> +#include <linux/if_packet.h>
> +#include <linux/if_arp.h>
> +
> +#include <net/sock.h>
> +
> +#include <asm/mmu_context.h>
> +
> +#include "vhost.h"
> +
> +enum {
> + VHOST_MEMORY_MAX_NREGIONS = 64,
> +};
> +
> +struct workqueue_struct *vhost_workqueue;
> +
> +static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh,
> + poll_table *pt)
> +{
> + struct vhost_poll *poll;
> + poll = container_of(pt, struct vhost_poll, table);
> +
> + poll->wqh = wqh;
> + add_wait_queue(wqh, &poll->wait);
> +}
> +
> +static int vhost_poll_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
> +{
> + struct vhost_poll *poll;
> + poll = container_of(wait, struct vhost_poll, wait);
> + if (!((unsigned long)key & poll->mask))
> + return 0;
> +
> + queue_work(vhost_workqueue, &poll->work);
> + return 0;
> +}
> +
> +/* Init poll structure */
> +void vhost_poll_init(struct vhost_poll *poll, work_func_t func,
> + unsigned long mask)
> +{
> + INIT_WORK(&poll->work, func);
> + init_waitqueue_func_entry(&poll->wait, vhost_poll_wakeup);
> + init_poll_funcptr(&poll->table, vhost_poll_func);
> + poll->mask = mask;
> +}
> +
> +/* Start polling a file. We add ourselves to file's wait queue. The user must
> + * keep a reference to a file until after vhost_poll_stop is called. */
> +void vhost_poll_start(struct vhost_poll *poll, struct file *file)
> +{
> + unsigned long mask;
> + mask = file->f_op->poll(file, &poll->table);
> + if (mask)
> + vhost_poll_wakeup(&poll->wait, 0, 0, (void *)mask);
> +}
> +
> +/* Stop polling a file. After this function returns, it becomes safe to drop the
> + * file reference. You must also flush afterwards. */
> +void vhost_poll_stop(struct vhost_poll *poll)
> +{
> + remove_wait_queue(poll->wqh, &poll->wait);
> +}
> +
> +/* Flush any work that has been scheduled. When calling this, don't hold any
> + * locks that are also used by the callback. */
> +void vhost_poll_flush(struct vhost_poll *poll)
> +{
> + flush_work(&poll->work);
> +}
> +
> +long vhost_dev_init(struct vhost_dev *dev, struct vhost_virtqueue *vqs, int nvqs)
> +{
> + int i;
> + dev->vqs = vqs;
> + dev->nvqs = nvqs;
> + mutex_init(&dev->mutex);
> +
> + for(i = 0; i < dev->nvqs; ++i) {
> + dev->vqs[i].dev = dev;
> + mutex_init(&dev->vqs[i].mutex);
> + if (dev->vqs[i].handle_kick)
> + vhost_poll_init(&dev->vqs[i].poll,
> + dev->vqs[i].handle_kick,
> + POLLIN);
> + }
> + return 0;
> +}
> +
> +/* User should have device mutex */
> +long vhost_dev_check_owner(struct vhost_dev *dev)
> +{
> + return dev->mm == current->mm ? 0 : -EPERM;
> +}
> +
> +/* User should have device mutex */
> +static long vhost_dev_set_owner(struct vhost_dev *dev)
> +{
> + if (dev->mm)
> + return -EBUSY;
> + dev->mm = get_task_mm(current);
> + return 0;
> +}
> +
> +/* User should have device mutex */
> +long vhost_dev_reset_owner(struct vhost_dev *dev)
> +{
> + struct vhost_memory *memory;
> +
> + /* Restore memory to default 1:1 mapping. */
> + memory = kmalloc(offsetof(struct vhost_memory, regions) +
> + 2 * sizeof *memory->regions, GFP_KERNEL);
> + if (!memory)
> + return -ENOMEM;
> +
> + vhost_dev_cleanup(dev);
> +
> + memory->nregions = 2;
> + memory->regions[0].guest_phys_addr = 1;
> + memory->regions[0].userspace_addr = 1;
> + memory->regions[0].memory_size = ~0ULL;
> + memory->regions[1].guest_phys_addr = 0;
> + memory->regions[1].userspace_addr = 0;
> + memory->regions[1].memory_size = 1;
> + dev->memory = memory;
> + return 0;
> +}
> +
> +/* User should have device mutex */
> +void vhost_dev_cleanup(struct vhost_dev *dev)
> +{
> + int i;
> + for(i = 0; i < dev->nvqs; ++i) {
> + if (dev->vqs[i].kick && dev->vqs[i].handle_kick) {
> + vhost_poll_stop(&dev->vqs[i].poll);
> + vhost_poll_flush(&dev->vqs[i].poll);
> + }
> + if (dev->vqs[i].error_ctx)
> + eventfd_ctx_put(dev->vqs[i].error_ctx);
> + if (dev->vqs[i].error)
> + fput(dev->vqs[i].error);
> + if (dev->vqs[i].kick)
> + fput(dev->vqs[i].kick);
> + if (dev->vqs[i].call_ctx)
> + eventfd_ctx_put(dev->vqs[i].call_ctx);
> + if (dev->vqs[i].call)
> + fput(dev->vqs[i].call);
> + dev->vqs[i].error_ctx = NULL;
> + dev->vqs[i].error = NULL;
> + dev->vqs[i].kick = NULL;
> + dev->vqs[i].call_ctx = NULL;
> + dev->vqs[i].call = NULL;
> + }
> + /* No one will access memory at this point */
> + kfree(dev->memory);
> + dev->memory = NULL;
> + if (dev->mm)
> + mmput(dev->mm);
> + dev->mm = NULL;
> +}
> +
> +static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
> +{
> + struct vhost_memory mem, *newmem, *oldmem;
> + unsigned long size = offsetof(struct vhost_memory, regions);
> + long r;
> + r = copy_from_user(&mem, m, size);
> + if (r)
> + return r;
> + if (mem.padding)
> + return -EOPNOTSUPP;
> + if (mem.nregions > VHOST_MEMORY_MAX_NREGIONS)
> + return -E2BIG;
> + newmem = kmalloc(size + mem.nregions * sizeof *m->regions, GFP_KERNEL);
> + if (!newmem)
> + return -ENOMEM;
> +
> + memcpy(newmem, &mem, size);
> + r = copy_from_user(newmem->regions, m->regions,
> + mem.nregions * sizeof *m->regions);
> + if (r) {
> + kfree(newmem);
> + return r;
> + }
> + oldmem = d->memory;
> + rcu_assign_pointer(d->memory, newmem);
> + synchronize_rcu();
> + kfree(oldmem);
> + return 0;
> +}
> +
> +static int init_used(struct vhost_virtqueue *vq)
> +{
> + u16 flags = 0;
> + int r = put_user(flags, &vq->used->flags);
> + if (r)
> + return r;
> + return get_user(vq->last_used_idx, &vq->used->idx);
> +}
> +
> +static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp)
> +{
> + struct file *eventfp, *filep = NULL, *pollstart = NULL, *pollstop = NULL;
> + struct eventfd_ctx *ctx = NULL;
> + u32 __user *idxp = argp;
> + struct vhost_virtqueue *vq;
> + struct vhost_vring_state s;
> + struct vhost_vring_file f;
> + struct vhost_vring_addr a;
> + u32 idx;
> + long r;
> +
> + r = get_user(idx, idxp);
> + if (r < 0)
> + return r;
> + if (idx > d->nvqs)
> + return -ENOBUFS;
> +
> + vq = d->vqs + idx;
> +
> + mutex_lock(&vq->mutex);
> +
> + switch (ioctl) {
> + case VHOST_SET_VRING_NUM:
> + r = copy_from_user(&s, argp, sizeof s);
> + if (r < 0)
> + break;
> + if (s.num > 0xffff) {
> + r = -EINVAL;
> + break;
> + }
> + vq->num = s.num;
> + break;
> + case VHOST_SET_VRING_BASE:
> + r = copy_from_user(&s, argp, sizeof s);
> + if (r < 0)
> + break;
> + if (s.num > 0xffff) {
> + r = -EINVAL;
> + break;
> + }
> + vq->last_avail_idx = s.num;
> + break;
> + case VHOST_GET_VRING_BASE:
> + s.index = idx;
> + s.num = vq->last_avail_idx;
> + r = copy_to_user(argp, &s, sizeof s);
> + break;
> + case VHOST_SET_VRING_DESC:
> + r = copy_from_user(&a, argp, sizeof a);
> + if (r < 0)
> + break;
> + if (a.padding) {
> + r = -EOPNOTSUPP;
> + break;
> + }
> + if ((u64)(long)a.user_addr != a.user_addr) {
> + r = -EFAULT;
> + break;
> + }
> + vq->desc = (void __user *)(long)a.user_addr;
> + break;
> + case VHOST_SET_VRING_AVAIL:
> + r = copy_from_user(&a, argp, sizeof a);
> + if (r < 0)
> + break;
> + if (a.padding) {
> + r = -EOPNOTSUPP;
> + break;
> + }
> + if ((u64)(long)a.user_addr != a.user_addr) {
> + r = -EFAULT;
> + break;
> + }
> + vq->avail = (void __user *)(long)a.user_addr;
> + break;
> + case VHOST_SET_VRING_USED:
> + r = copy_from_user(&a, argp, sizeof a);
> + if (r < 0)
> + break;
> + if (a.padding) {
> + r = -EOPNOTSUPP;
> + break;
> + }
> + if ((u64)(long)a.user_addr != a.user_addr) {
> + r = -EFAULT;
> + break;
> + }
> + vq->used = (void __user *)(long)a.user_addr;
> + r = init_used(vq);
> + if (r)
> + break;
> + break;
> + case VHOST_SET_VRING_KICK:
> + r = copy_from_user(&f, argp, sizeof f);
> + if (r < 0)
> + break;
> + eventfp = f.fd == -1 ? NULL: eventfd_fget(f.fd);
> + if (IS_ERR(eventfp))
> + return PTR_ERR(eventfp);
> + if (eventfp != vq->kick) {
> + pollstop = filep = vq->kick;
> + pollstart = vq->kick = eventfp;
> + } else
> + filep = eventfp;
> + break;
> + case VHOST_SET_VRING_CALL:
> + r = copy_from_user(&f, argp, sizeof f);
> + if (r < 0)
> + break;
> + eventfp = f.fd == -1 ? NULL: eventfd_fget(f.fd);
> + if (IS_ERR(eventfp))
> + return PTR_ERR(eventfp);
> + if (eventfp != vq->call) {
> + filep = vq->call;
> + ctx = vq->call_ctx;
> + vq->call = eventfp;
> + vq->call_ctx = eventfp ?
> + eventfd_ctx_fileget(eventfp) : NULL;
> + } else
> + filep = eventfp;
> + break;
> + case VHOST_SET_VRING_ERR:
> + r = copy_from_user(&f, argp, sizeof f);
> + if (r < 0)
> + break;
> + eventfp = f.fd == -1 ? NULL: eventfd_fget(f.fd);
> + if (IS_ERR(eventfp))
> + return PTR_ERR(eventfp);
> + if (eventfp != vq->error) {
> + filep = vq->error;
> + vq->error = eventfp;
> + ctx = vq->error_ctx;
> + vq->error_ctx = eventfp ?
> + eventfd_ctx_fileget(eventfp) : NULL;
> + } else
> + filep = eventfp;
> + break;
> + default:
> + r = -ENOTTY;
> + }
> +
> + if (pollstop && vq->handle_kick)
> + vhost_poll_stop(&vq->poll);
> +
> + if (ctx)
> + eventfd_ctx_put(ctx);
> + if (filep)
> + fput(filep);
> +
> + if (pollstart && vq->handle_kick)
> + vhost_poll_start(&vq->poll, vq->kick);
> +
> + mutex_unlock(&vq->mutex);
> +
> + if (pollstop && vq->handle_kick)
> + vhost_poll_flush(&vq->poll);
> + return 0;
> +}
> +
> +long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, unsigned long arg)
> +{
> + void __user *argp = (void __user *)arg;
> + long r;
> +
> + mutex_lock(&d->mutex);
> + if (ioctl == VHOST_SET_OWNER) {
> + r = vhost_dev_set_owner(d);
> + goto done;
> + }
> +
> + r = vhost_dev_check_owner(d);
> + if (r)
> + goto done;
> +
> + switch (ioctl) {
> + case VHOST_SET_MEM_TABLE:
> + r = vhost_set_memory(d, argp);
> + break;
> + default:
> + r = vhost_set_vring(d, ioctl, argp);
> + break;
> + }
> +done:
> + mutex_unlock(&d->mutex);
> + return r;
> +}
> +
> +static const struct vhost_memory_region *find_region(struct vhost_memory *mem,
> + __u64 addr, __u32 len)
> +{
> + struct vhost_memory_region *reg;
> + int i;
> + /* linear search is not brilliant, but we really have on the order of 6
> + * regions in practice */
> + for (i = 0; i < mem->nregions; ++i) {
> + reg = mem->regions + i;
> + if (reg->guest_phys_addr <= addr &&
> + reg->guest_phys_addr + reg->memory_size - 1 >= addr)
> + return reg;
> + }
> + return NULL;
> +}
> +
> +/* FIXME: this does not handle a region that spans multiple
> + * address/len pairs */
> +int translate_desc(struct vhost_dev *dev, u64 addr, u32 len,
> + struct iovec iov[], int iov_count, int iov_size,
> + unsigned *num)
> +{
> + const struct vhost_memory_region *reg;
> + struct vhost_memory *mem;
> + struct iovec *_iov;
> + u64 s = 0;
> + int ret = 0;
> +
> + rcu_read_lock();
> +
> + mem = rcu_dereference(dev->memory);
> + while ((u64)len > s) {
> + u64 size;
> + if (*num + iov_count >= iov_size) {
> + ret = -ENOBUFS;
> + break;
> + }
> + reg = find_region(mem, addr, len);
> + if (!reg) {
> + ret = -EFAULT;
> + break;
> + }
> + _iov = iov + iov_count + *num;
> + size = reg->memory_size - addr + reg->guest_phys_addr;
> + _iov->iov_len = min((u64)len, size);
> + _iov->iov_base = (void *)
> + (reg->userspace_addr + addr - reg->guest_phys_addr);
> + s += size;
> + addr += size;
> + ++*num;
> + }
> +
> + rcu_read_unlock();
> + return ret;
> +}
> +
> +/* Each buffer in the virtqueues is actually a chain of descriptors. This
> + * function returns the next descriptor in the chain, or vq->vring.num if we're
> + * at the end. */
> +static unsigned next_desc(struct vhost_virtqueue *vq, struct vring_desc *desc)
> +{
> + unsigned int next;
> +
> + /* If this descriptor says it doesn't chain, we're done. */
> + if (!(desc->flags & VRING_DESC_F_NEXT))
> + return vq->num;
> +
> + /* Check they're not leading us off end of descriptors. */
> + next = desc->next;
> + /* Make sure compiler knows to grab that: we don't want it changing! */
> + /* We will use the result as an index in an array, so most
> + * architectures only need a compiler barrier here. */
> + read_barrier_depends();
> +
> + if (next >= vq->num) {
> + vq_err(vq, "Desc next is %u > %u", next, vq->num);
> + return vq->num;
> + }
> +
> + return next;
> +}
> +
> +/* This looks in the virtqueue and for the first available buffer, and converts
> + * it to an iovec for convenient access. Since descriptors consist of some
> + * number of output then some number of input descriptors, it's actually two
> + * iovecs, but we pack them into one and note how many of each there were.
> + *
> + * This function returns the descriptor number found, or vq->num (which
> + * is never a valid descriptor number) if none was found. */
> +unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> + struct iovec iov[],
> + unsigned int *out_num, unsigned int *in_num)
> +{
> + struct vring_desc desc;
> + unsigned int i, head;
> + u16 last_avail_idx, idx;
> +
> + /* Check it isn't doing very strange things with descriptor numbers. */
> + last_avail_idx = vq->last_avail_idx;
> + if (get_user(idx, &vq->avail->idx)) {
> + vq_err(vq, "Failed to access avail idx at %p\n",
> + &vq->avail->idx);
> + return vq->num;
> + }
> +
> + if ((u16)(idx - last_avail_idx) > vq->num) {
> + vq_err(vq, "Guest moved used index from %u to %u",
> + last_avail_idx, idx);
> + return vq->num;
> + }
> +
> + /* If there's nothing new since last we looked, return invalid. */
> + if (idx == last_avail_idx)
> + return vq->num;
> +
> + /* Grab the next descriptor number they're advertising, and increment
> + * the index we've seen. */
> + if (get_user(head, &vq->avail->ring[last_avail_idx % vq->num])) {
> + vq_err(vq, "Failed to read head: idx %d address %p\n",
> + idx, &vq->avail->ring[last_avail_idx % vq->num]);
> + return vq->num;
> + }
> +
> + /* If their number is silly, that's a fatal mistake. */
> + if (head >= vq->num) {
> + vq_err(vq, "Guest says index %u > %u is available",
> + head, vq->num);
> + return vq->num;
> + }
> +
> + vq->last_avail_idx++;
> +
> + /* When we start there are none of either input nor output. */
> + *out_num = *in_num = 0;
> +
> + i = head;
> + do {
> + unsigned *num;
> + unsigned iov_count;
> + if (copy_from_user(&desc, vq->desc + i, sizeof desc)) {
> + vq_err(vq, "Failed to get descriptor: idx %d addr %p\n",
> + i, vq->desc + i);
> + return vq->num;
> + }
> + /* If this is an input descriptor, increment that count. */
> + if (desc.flags & VRING_DESC_F_WRITE) {
> + num = in_num;
> + iov_count = *out_num;
> + } else {
> + /* If it's an output descriptor, they're all supposed
> + * to come before any input descriptors. */
> + if (*in_num) {
> + vq_err(vq, "Descriptor has out after in: "
> + "idx %d\n", i);
> + return vq->num;
> + }
> + num = out_num;
> + iov_count = *in_num;
> + }
> + if (translate_desc(dev, desc.addr, desc.len, iov, iov_count,
> + VHOST_NET_MAX_SG, num)) {
> + vq_err(vq, "Failed to translate descriptor: idx %d\n",
> + i);
> + return vq->num;
> + }
> +
> + /* If we've got too many, that implies a descriptor loop. */
> + if (*out_num + *in_num > vq->num) {
> + vq_err(vq, "Looped descriptor: idx %d\n", i);
> + return vq->num;
> + }
> + } while ((i = next_desc(vq, &desc)) != vq->num);
> +
> + vq->inflight++;
> + return head;
> +}
> +
> +/* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */
> +void vhost_discard_vq_desc(struct vhost_virtqueue *vq)
> +{
> + vq->last_avail_idx--;
> + vq->inflight--;
> +}
> +
> +/* After we've used one of their buffers, we tell them about it. We'll then
> + * want to send them an interrupt, using vq->call. */
> +int vhost_add_used(struct vhost_virtqueue *vq,
> + unsigned int head, int len)
> +{
> + struct vring_used_elem *used;
> +
> + /* The virtqueue contains a ring of used buffers. Get a pointer to the
> + * next entry in that used ring. */
> + used = &vq->used->ring[vq->last_used_idx % vq->num];
> + if (put_user(head, &used->id)) {
> + vq_err(vq, "Failed to write used id");
> + return -EFAULT;
> + }
> + if (put_user(len, &used->len)) {
> + vq_err(vq, "Failed to write used len");
> + return -EFAULT;
> + }
> + /* Make sure buffer is written before we update index. */
> + wmb();
> + if (put_user(vq->last_used_idx + 1, &vq->used->idx)) {
> + vq_err(vq, "Failed to increment used idx");
> + return -EFAULT;
> + }
> + vq->last_used_idx++;
> + vq->inflight--;
> + return 0;
> +}
> +
> +/* This actually sends the interrupt for this virtqueue */
> +void vhost_trigger_irq(struct vhost_virtqueue *vq)
> +{
> + __u16 flags = 0;
> + if (get_user(flags, &vq->avail->flags)) {
> + vq_err(vq, "Failed to get flags");
> + return;
> + }
> +
> + /* If they don't want an interrupt, don't send one, unless empty. */
> + if ((flags & VRING_AVAIL_F_NO_INTERRUPT) && vq->inflight)
> + return;
> +
> + /* Send the Guest an interrupt tell them we used something up. */
> + if (vq->call_ctx)
> + eventfd_signal(vq->call_ctx, 1);
> +}
> +
> +/* And here's the combo meal deal. Supersize me! */
> +void vhost_add_used_and_trigger(struct vhost_virtqueue *vq,
> + unsigned int head, int len)
> +{
> + vhost_add_used(vq, head, len);
> + vhost_trigger_irq(vq);
> +}
> +
> +int vhost_init(void)
> +{
> + vhost_workqueue = create_workqueue("vhost");
> + if (!vhost_workqueue)
> + return -ENOMEM;
> + return 0;
> +}
> +
> +void vhost_cleanup(void)
> +{
> + destroy_workqueue(vhost_workqueue);
> +}
> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> new file mode 100644
> index 0000000..7f7ffcd
> --- /dev/null
> +++ b/drivers/vhost/vhost.h
> @@ -0,0 +1,108 @@
> +#ifndef _VHOST_H
> +#define _VHOST_H
> +
> +#include <linux/eventfd.h>
> +#include <linux/vhost.h>
> +#include <linux/mm.h>
> +#include <linux/mutex.h>
> +#include <linux/workqueue.h>
> +#include <linux/poll.h>
> +#include <linux/file.h>
> +#include <linux/skbuff.h>
> +
> +struct vhost_device;
> +
> +enum {
> + VHOST_NET_MAX_SG = MAX_SKB_FRAGS + 2,
> +};
> +
> +/* Poll a file (eventfd or socket) */
> +/* Note: there's nothing vhost specific about this structure. */
> +struct vhost_poll {
> + poll_table table;
> + wait_queue_head_t *wqh;
> + wait_queue_t wait;
> + /* struct which will handle all actual work. */
> + struct work_struct work;
> + unsigned long mask;
> +};
> +
> +void vhost_poll_init(struct vhost_poll *poll, work_func_t func,
> + unsigned long mask);
> +void vhost_poll_start(struct vhost_poll *poll, struct file *file);
> +void vhost_poll_stop(struct vhost_poll *poll);
> +void vhost_poll_flush(struct vhost_poll *poll);
> +
> +/* The virtqueue structure describes a queue attached to a device. */
> +struct vhost_virtqueue {
> + struct vhost_dev *dev;
> +
> + /* The actual ring of buffers. */
> + struct mutex mutex;
> + unsigned int num;
> + struct vring_desc __user *desc;
> + struct vring_avail __user *avail;
> + struct vring_used __user *used;
> + struct file *kick;
> + struct file *call;
> + struct file *error;
> + struct eventfd_ctx *call_ctx;
> + struct eventfd_ctx *error_ctx;
> +
> + struct vhost_poll poll;
> +
> + /* The routine to call when the Guest pings us, or timeout. */
> + work_func_t handle_kick;
> +
> + /* Last available index we saw. */
> + u16 last_avail_idx;
> +
> + /* Last index we used. */
> + u16 last_used_idx;
> +
> + /* Outstanding buffers */
> + unsigned int inflight;
> +
> + /* Is this blocked? */
> + bool blocked;
> +
> + struct iovec iov[VHOST_NET_MAX_SG];
> +
> +} ____cacheline_aligned;
> +
> +struct vhost_dev {
> + /* Readers use RCU to access memory table pointer.
> + * Writers use mutex below.*/
> + struct vhost_memory *memory;
> + struct mm_struct *mm;
> + struct vhost_virtqueue *vqs;
> + int nvqs;
> + struct mutex mutex;
> +};
> +
> +long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue *vqs, int nvqs);
> +long vhost_dev_check_owner(struct vhost_dev *);
> +long vhost_dev_reset_owner(struct vhost_dev *);
> +void vhost_dev_cleanup(struct vhost_dev *);
> +long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, unsigned long arg);
> +
> +unsigned vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
> + struct iovec iov[],
> + unsigned int *out_num, unsigned int *in_num);
> +void vhost_discard_vq_desc(struct vhost_virtqueue *);
> +
> +int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
> +void vhost_trigger_irq(struct vhost_virtqueue *);
> +void vhost_add_used_and_trigger(struct vhost_virtqueue *,
> + unsigned int head, int len);
> +
> +int vhost_init(void);
> +void vhost_cleanup(void);
> +
> +#define vq_err(vq, fmt, ...) do { \
> + printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__); \
> + if ((vq)->error_ctx) \
> + eventfd_signal((vq)->error_ctx, 1);\
> + } while (0)
> +
> +#endif
> diff --git a/include/linux/Kbuild b/include/linux/Kbuild
> index dec2f18..975df9a 100644
> --- a/include/linux/Kbuild
> +++ b/include/linux/Kbuild
> @@ -360,6 +360,7 @@ unifdef-y += uio.h
> unifdef-y += unistd.h
> unifdef-y += usbdevice_fs.h
> unifdef-y += utsname.h
> +unifdef-y += vhost.h
> unifdef-y += videodev2.h
> unifdef-y += videodev.h
> unifdef-y += virtio_config.h
> diff --git a/include/linux/miscdevice.h b/include/linux/miscdevice.h
> index 0521177..781a8bb 100644
> --- a/include/linux/miscdevice.h
> +++ b/include/linux/miscdevice.h
> @@ -30,6 +30,7 @@
> #define HPET_MINOR 228
> #define FUSE_MINOR 229
> #define KVM_MINOR 232
> +#define VHOST_NET_MINOR 233
Would recommend using DYNAMIC-MINOR.
> #define MISC_DYNAMIC_MINOR 255
>
> struct device;
> diff --git a/include/linux/vhost.h b/include/linux/vhost.h
> new file mode 100644
> index 0000000..9ec6d5f
> --- /dev/null
> +++ b/include/linux/vhost.h
> @@ -0,0 +1,100 @@
> +#ifndef _LINUX_VHOST_H
> +#define _LINUX_VHOST_H
> +/* Userspace interface for in-kernel virtio accelerators. */
> +
> +/* vhost is used to reduce the number of system calls involved in virtio.
> + *
> + * Existing virtio net code is used in the guest without modification.
> + *
> + * This header includes interface used by userspace hypervisor for
> + * device configuration.
> + */
> +
> +#include <linux/types.h>
> +#include <linux/compiler.h>
> +#include <linux/ioctl.h>
> +#include <linux/virtio_config.h>
> +#include <linux/virtio_ring.h>
> +
> +struct vhost_vring_state {
> + unsigned int index;
> + unsigned int num;
> +};
> +
> +struct vhost_vring_file {
> + unsigned int index;
> + int fd;
> +};
> +
> +struct vhost_vring_addr {
> + unsigned int index;
> + unsigned int padding;
> + __u64 user_addr;
> +};
> +
> +struct vhost_memory_region {
> + __u64 guest_phys_addr;
> + __u64 memory_size; /* bytes */
> + __u64 userspace_addr;
> + __u64 padding; /* read/write protection? */
> +};
> +
> +struct vhost_memory {
> + __u32 nregions;
> + __u32 padding;
> + struct vhost_memory_region regions[0];
> +};
> +
> +/* ioctls */
> +
> +#define VHOST_VIRTIO 0xAF
> +
> +/* Features bitmask for forward compatibility. Transport bits must be zero. */
> +#define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u32)
> +#define VHOST_ACK_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u32)
> +
> +/* Set current process as the (exclusive) owner of this file descriptor. This
> + * must be called before any other vhost command. Further calls to
> + * VHOST_OWNER_SET fail until VHOST_OWNER_RESET is called. */
> +#define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01)
> +/* Give up ownership, and reset the device to default values.
> + * Allows subsequent call to VHOST_OWNER_SET to succeed. */
> +#define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02)
> +
> +/* Set up/modify memory layout */
> +#define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory)
> +
> +/* Ring setup. These parameters can not be modified while ring is running
> + * (bound to a device). */
> +/* Set number of descriptors in ring */
> +#define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state)
> +/* Start of array of descriptors (virtually contiguous) */
> +#define VHOST_SET_VRING_DESC _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr)
> +/* Used structure address */
> +#define VHOST_SET_VRING_USED _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_addr)
> +/* Available structure address */
> +#define VHOST_SET_VRING_AVAIL _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_addr)
> +/* Base value where queue looks for available descriptors */
> +#define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state)
> +/* Get accessor: reads index, writes value in num */
> +#define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x14, struct vhost_vring_state)
> +
> +/* The following ioctls use eventfd file descriptors to signal and poll
> + * for events. */
> +
> +/* Set eventfd to poll for added buffers */
> +#define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file)
> +/* Set eventfd to signal when buffers have beed used */
> +#define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file)
> +/* Set eventfd to signal an error */
> +#define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
> +
> +/* VHOST_NET specific defines */
> +
> +/* Attach virtio net device to a raw socket. The socket must be already
> + * bound to an ethernet device, this device will be used for transmit.
> + * Pass -1 to unbind from the socket and the transmit device.
> + * This can be used to stop the device (e.g. for migration). */
> +#define VHOST_NET_SET_SOCKET _IOW(VHOST_VIRTIO, 0x30, int)
> +
> +#endif
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* RE: Receive side performance issue with multi-10-GigE and NUMA
From: Brandeburg, Jesse @ 2009-08-12 0:02 UTC (permalink / raw)
To: Bill Fink, Neil Horman
Cc: Andrew Gallatin, Brice Goglin, Linux Network Developers,
Yinghai Lu, jbarnes@virtuousgeek.org
In-Reply-To: <20090811033210.6b422ed1.billfink@mindspring.com>
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Bill Fink wrote:
> On Sat, 8 Aug 2009, Neil Horman wrote:
>
>> On Sat, Aug 08, 2009 at 02:21:36PM -0400, Andrew Gallatin wrote:
>>> Neil Horman wrote:
>>>> On Sat, Aug 08, 2009 at 07:08:20AM -0400, Andrew Gallatin wrote:
>>>>> Bill Fink wrote:
>>>>>> On Fri, 07 Aug 2009, Andrew Gallatin wrote:
>>>>>>
>>>>>>> Bill Fink wrote:
>>>>>>>
>>>>>>>> All sysfs local_cpus values are the same (00000000,000000ff),
>>>>>>>> so yes they are also wrong.
bill, I recently helped Jesse Barnes push a patch that addresses this kind
of issue on CoreI7, the root cause was the numa_node variable was
initialized based on slot on AMD systems, but needed to be set to -1 by
default on systems with a uniform IOH to slot architecture.
here is the commit ID:
http://git.kernel.org/?p=linux/kernel/git/sfr/linux-next.git;a=commit;h=3c38
d674be519109696746192943a6d524019f7f
I'm not sure it is in linus' tree yet, this link is to net-next
Maybe see if it helps?
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* Re: [PATCH] Fix Warnings from net/netlink/genetlink.c
From: Marcel Holtmann @ 2009-08-11 23:57 UTC (permalink / raw)
To: vibi_sreenivasan; +Cc: netdev, Johannes Berg, Thomas Graf, linux-next
In-Reply-To: <1249985224.13065.11.camel@HunTEr>
Hi Vibi,
> net/netlink/genetlink.c: In function `genl_register_mc_group':
> net/netlink/genetlink.c:139: warning: 'err' might be used uninitialized in this function
>
> Signed-off-by: vibi sreenivasan <vibi_sreenivasan@cms.com>
> ---
> net/netlink/genetlink.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
> index 575c643..66f6ba0 100644
> --- a/net/netlink/genetlink.c
> +++ b/net/netlink/genetlink.c
> @@ -136,7 +136,7 @@ int genl_register_mc_group(struct genl_family *family,
> {
> int id;
> unsigned long *new_groups;
> - int err;
> + int err = 0;
>
> BUG_ON(grp->name[0] == '\0');
this looks fishy. How does gcc thinks this variable is uninitialized. If
I look at the code in Linus' tree, I don't see it.
Regards
Marcel
^ permalink raw reply
* Re: [PATCHv2 0/2] vhost: a kernel-level virtio server
From: Gregory Haskins @ 2009-08-11 23:49 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: netdev, virtualization, kvm, linux-kernel, mingo, linux-mm, akpm,
hpa
In-Reply-To: <20090811212743.GA26309@redhat.com>
[-- Attachment #1: Type: text/plain, Size: 758 bytes --]
Michael S. Tsirkin wrote:
> This implements vhost: a kernel-level backend for virtio,
> The main motivation for this work is to reduce virtualization
> overhead for virtio by removing system calls on data path,
> without guest changes. For virtio-net, this removes up to
> 4 system calls per packet: vm exit for kick, reentry for kick,
> iothread wakeup for packet, interrupt injection for packet.
>
> Some more detailed description attached to the patch itself.
>
> The patches are against 2.6.31-rc4. I'd like them to go into linux-next
> and down the road 2.6.32 if possible. Please comment.
I will add this series to my benchmark run in the next day or so. Any
specific instructions on how to set it up and run?
Regards,
-Greg
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* multicast routing and multiple interfaces with same IP
From: Ilia K. @ 2009-08-11 23:26 UTC (permalink / raw)
To: netdev
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Hi All,
When routing daemon wants to enable forwarding of multicast traffic it
performs something like:
struct vifctl vc = {
.vifc_vifi = 1,
.vifc_flags = 0,
.vifc_threshold = 1,
.vifc_rate_limit = 0,
.vifc_lcl_addr = ip, /* <--- ip address of physical interface, e.g. eth0 */
.vifc_rmt_addr.s_addr = htonl(INADDR_ANY),
};
setsockopt(fd, IPPROTO_IP, MRT_ADD_VIF, &vc, sizeof(vc));
This leads (in the kernel) to call to vif_add() function call which
search the (physical) device using assigned IP address:
dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
It seems like API (struct vifctl) does not allow to specify an
interface other way than using it's IP, and if there are more than a
single interface with specified IP only the first one will be found
(for example it makes problems when tunnel is configured using the
same IP as underlying interface).
Am I correct in identifying the problem?
I can propose the attached patch against 2.6.30.4.
Regards,
Ilia.
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=== modified file 'include/linux/mroute.h'
--- old/include/linux/mroute.h 2009-08-10 11:17:32 +0000
+++ new/include/linux/mroute.h 2009-08-11 20:39:14 +0000
@@ -61,11 +61,13 @@
unsigned int vifc_rate_limit; /* Rate limiter values (NI) */
struct in_addr vifc_lcl_addr; /* Our address */
struct in_addr vifc_rmt_addr; /* IPIP tunnel addr */
+ int ifindex; /* Local interface index */
};
#define VIFF_TUNNEL 0x1 /* IPIP tunnel */
#define VIFF_SRCRT 0x2 /* NI */
#define VIFF_REGISTER 0x4 /* register vif */
+#define VIFF_USE_IFINDEX 0x8 /* use ifindex to find an interface */
/*
* Cache manipulation structures for mrouted and PIMd
=== modified file 'net/ipv4/ipmr.c'
--- old/net/ipv4/ipmr.c 2009-08-10 11:17:32 +0000
+++ new/net/ipv4/ipmr.c 2009-08-11 22:15:24 +0000
@@ -470,6 +470,18 @@
return err;
}
break;
+ case VIFF_USE_IFINDEX:
+ dev = dev_get_by_index(net, vifc->ifindex);
+ if (!dev)
+ return -ENODEV;
+ if (dev->ip_ptr == NULL)
+ return -EADDRNOTAVAIL;
+ err = dev_set_allmulti(dev, 1);
+ if (err) {
+ dev_put(dev);
+ return err;
+ }
+ break;
case 0:
dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
if (!dev)
^ permalink raw reply
* [net-2.6 PATCH] ixgbe: fix issues setting rx-usecs with legacy interrupts
From: Jeff Kirsher @ 2009-08-11 23:18 UTC (permalink / raw)
To: davem; +Cc: netdev, gospo, Don Skidmore, Jeff Kirsher
From: Don Skidmore <donald.c.skidmore@intel.com>
Currently setting rx-usecs when the interface is in legacy interrupt
mode it is not immediate. We were only setting EITR for each MSIx
vector and since this count would be zero for legacy mode it wasn't
set until after a reset. This patch corrects that by checking what
mode we are in and then setting EITR accordingly.
Signed-off-by: Don Skidmore <donald.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---
drivers/net/ixgbe/ixgbe_ethtool.c | 27 +++++++++++++++++++--------
1 files changed, 19 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ixgbe/ixgbe_ethtool.c b/drivers/net/ixgbe/ixgbe_ethtool.c
index 79144e9..dff8dfa 100644
--- a/drivers/net/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ixgbe/ixgbe_ethtool.c
@@ -1948,6 +1948,7 @@ static int ixgbe_set_coalesce(struct net_device *netdev,
struct ethtool_coalesce *ec)
{
struct ixgbe_adapter *adapter = netdev_priv(netdev);
+ struct ixgbe_q_vector *q_vector;
int i;
if (ec->tx_max_coalesced_frames_irq)
@@ -1982,14 +1983,24 @@ static int ixgbe_set_coalesce(struct net_device *netdev,
adapter->itr_setting = 0;
}
- for (i = 0; i < adapter->num_msix_vectors - NON_Q_VECTORS; i++) {
- struct ixgbe_q_vector *q_vector = adapter->q_vector[i];
- if (q_vector->txr_count && !q_vector->rxr_count)
- /* tx vector gets half the rate */
- q_vector->eitr = (adapter->eitr_param >> 1);
- else
- /* rx only or mixed */
- q_vector->eitr = adapter->eitr_param;
+ /* MSI/MSIx Interrupt Mode */
+ if (adapter->flags &
+ (IXGBE_FLAG_MSIX_ENABLED | IXGBE_FLAG_MSI_ENABLED)) {
+ int num_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;
+ for (i = 0; i < num_vectors; i++) {
+ q_vector = adapter->q_vector[i];
+ if (q_vector->txr_count && !q_vector->rxr_count)
+ /* tx vector gets half the rate */
+ q_vector->eitr = (adapter->eitr_param >> 1);
+ else
+ /* rx only or mixed */
+ q_vector->eitr = adapter->eitr_param;
+ ixgbe_write_eitr(q_vector);
+ }
+ /* Legacy Interrupt Mode */
+ } else {
+ q_vector = adapter->q_vector[0];
+ q_vector->eitr = adapter->eitr_param;
ixgbe_write_eitr(q_vector);
}
^ permalink raw reply related
* Re: Receive side performance issue with multi-10-GigE and NUMA
From: Andi Kleen @ 2009-08-11 22:27 UTC (permalink / raw)
To: Bill Fink
Cc: Neil Horman, Andrew Gallatin, Brice Goglin,
Linux Network Developers, Yinghai Lu
In-Reply-To: <20090811033210.6b422ed1.billfink@mindspring.com>
Bill Fink <billfink@mindspring.com> writes:
>
> I originally tried to just use alloc_pages_node() instead of alloc_pages(),
> but it didn't help. As mentioned in an earlier e-mail, that seems to
> be because I discovered that doing:
>
> find /sys -name numa_node -exec grep . {} /dev/null \;
>
> revealed that the NUMA node associated with _all_ the PCI devices was
> always 0, when at least some of them should have been associated with
> NUMA node 2, including 6 of the 12 Myricom 10-GigE devices.
> I discovered today that the NUMA node cpulist/cpumap is also wrong.
> A cat of /sys/devices/system/node/node0/cpulist returns "0-7" (with a
> cpumask of 00000000,000000ff), while the cpulist for node2 is empty
> (with a cpumask of 00000000,00000000). The distance is correct,
> with "10 20" for node 0 and "20 10" for node2.
When the CPU nodes are not correct the device nodes are unlikely
to correct either. In fact your system likely has no node 1 configured,
right?
This information comes from the BIOS. So either your BIOS is broken
or you simply didn't enable NUMA mode in the BIOS, but configured
memory interleaving.
If you post dmesg output somewhere I can take a look.
-Andi
--
ak@linux.intel.com -- Speaking for myself only.
^ permalink raw reply
* Re: [PATCHv2 1/2] mm: export use_mm/unuse_mm to modules
From: Andrew Morton @ 2009-08-11 22:10 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: netdev, virtualization, kvm, linux-kernel, mingo, linux-mm, hpa
In-Reply-To: <20090811212752.GB26309@redhat.com>
On Wed, 12 Aug 2009 00:27:52 +0300
"Michael S. Tsirkin" <mst@redhat.com> wrote:
> vhost net module wants to do copy to/from user from a kernel thread,
> which needs use_mm (like what fs/aio has). Move that into mm/ and
> export to modules.
OK by me. Please include this change in the virtio patchset. Which I
shall cheerfully not be looking at :)
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* [PATCHv2 2/2] vhost_net: a kernel-level virtio server
From: Michael S. Tsirkin @ 2009-08-11 21:28 UTC (permalink / raw)
To: netdev, virtualization, kvm, linux-kernel, mingo, linux-mm, akpm
In-Reply-To: <cover.1249992497.git.mst@redhat.com>
What it is: vhost net is a character device that can be used to reduce
the number of system calls involved in virtio networking.
Existing virtio net code is used in the guest without modification.
There's similarity with vringfd, with some differences and reduced scope
- uses eventfd for signalling
- structures can be moved around in memory at any time (good for migration)
- support memory table and not just an offset (needed for kvm)
common virtio related code has been put in a separate file vhost.c and
can be made into a separate module if/when more backends appear. I used
Rusty's lguest.c as the source for developing this part : this supplied
me with witty comments I wouldn't be able to write myself.
What it is not: vhost net is not a bus, and not a generic new system
call. No assumptions are made on how guest performs hypercalls.
Userspace hypervisors are supported as well as kvm.
How it works: Basically, we connect virtio frontend (configured by
userspace) to a backend. The backend could be a network device, or a
tun-like device. In this version I only support raw socket as a backend,
which can be bound to e.g. SR IOV, or to macvlan device. Backend is
also configured by userspace, including vlan/mac etc.
Status:
This works for me, and I haven't see any crashes.
I have not run any benchmarks yet, compared to userspace, I expect to
see improved latency (as I save up to 4 system calls per packet) but not
bandwidth/CPU (as TSO and interrupt mitigation are not supported).
Features that I plan to look at in the future:
- TSO
- interrupt mitigation
- zero copy
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
v2
---
MAINTAINERS | 10 +
arch/x86/kvm/Kconfig | 1 +
drivers/Makefile | 1 +
drivers/vhost/Kconfig | 11 +
drivers/vhost/Makefile | 2 +
drivers/vhost/net.c | 411 +++++++++++++++++++++++++++
drivers/vhost/vhost.c | 663 ++++++++++++++++++++++++++++++++++++++++++++
drivers/vhost/vhost.h | 108 +++++++
include/linux/Kbuild | 1 +
include/linux/miscdevice.h | 1 +
include/linux/vhost.h | 100 +++++++
11 files changed, 1309 insertions(+), 0 deletions(-)
create mode 100644 drivers/vhost/Kconfig
create mode 100644 drivers/vhost/Makefile
create mode 100644 drivers/vhost/net.c
create mode 100644 drivers/vhost/vhost.c
create mode 100644 drivers/vhost/vhost.h
create mode 100644 include/linux/vhost.h
diff --git a/MAINTAINERS b/MAINTAINERS
index ebc2691..eb0c1da 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6312,6 +6312,16 @@ S: Maintained
F: Documentation/filesystems/vfat.txt
F: fs/fat/
+VIRTIO HOST (VHOST)
+P: Michael S. Tsirkin
+M: mst@redhat.com
+L: kvm@vger.kernel.org
+L: virtualization@lists.osdl.org
+L: netdev@vger.kernel.org
+S: Maintained
+F: drivers/vhost/
+F: include/linux/vhost.h
+
VIA RHINE NETWORK DRIVER
P: Roger Luethi
M: rl@hellgate.ch
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index b84e571..94f44d9 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -64,6 +64,7 @@ config KVM_AMD
# OK, it's a little counter-intuitive to do this, but it puts it neatly under
# the virtualization menu.
+source drivers/vhost/Kconfig
source drivers/lguest/Kconfig
source drivers/virtio/Kconfig
diff --git a/drivers/Makefile b/drivers/Makefile
index bc4205d..1551ae1 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -105,6 +105,7 @@ obj-$(CONFIG_HID) += hid/
obj-$(CONFIG_PPC_PS3) += ps3/
obj-$(CONFIG_OF) += of/
obj-$(CONFIG_SSB) += ssb/
+obj-$(CONFIG_VHOST_NET) += vhost/
obj-$(CONFIG_VIRTIO) += virtio/
obj-$(CONFIG_VLYNQ) += vlynq/
obj-$(CONFIG_STAGING) += staging/
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
new file mode 100644
index 0000000..d955406
--- /dev/null
+++ b/drivers/vhost/Kconfig
@@ -0,0 +1,11 @@
+config VHOST_NET
+ tristate "Host kernel accelerator for virtio net"
+ depends on NET && EVENTFD
+ ---help---
+ This kernel module can be loaded in host kernel to accelerate
+ guest networking with virtio_net. Not to be confused with virtio_net
+ module itself which needs to be loaded in guest kernel.
+
+ To compile this driver as a module, choose M here: the module will
+ be called vhost_net.
+
diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile
new file mode 100644
index 0000000..72dd020
--- /dev/null
+++ b/drivers/vhost/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_VHOST_NET) += vhost_net.o
+vhost_net-y := vhost.o net.o
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
new file mode 100644
index 0000000..a04ffd0
--- /dev/null
+++ b/drivers/vhost/net.c
@@ -0,0 +1,411 @@
+/* Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ *
+ * virtio-net server in host kernel.
+ */
+
+#include <linux/eventfd.h>
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+#include <linux/mmu_context.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/rcupdate.h>
+#include <linux/file.h>
+
+#include <linux/net.h>
+#include <linux/if_packet.h>
+#include <linux/if_arp.h>
+
+#include <net/sock.h>
+
+#include <asm/mmu_context.h>
+
+#include "vhost.h"
+
+enum {
+ VHOST_NET_VQ_RX = 0,
+ VHOST_NET_VQ_TX = 1,
+ VHOST_NET_VQ_MAX = 2,
+};
+
+struct vhost_net {
+ struct vhost_dev dev;
+ struct vhost_virtqueue vqs[VHOST_NET_VQ_MAX];
+ /* We use a kind of RCU to access sock pointer.
+ * All readers access it from workqueue,
+ * which makes it possible to flush the workqueue
+ * instead of synchronize_rcu. Therefore readers
+ * do not need rcu_read_lock/rcu_read_unlock.
+ * Writers use device mutex. */
+ struct socket *sock;
+ struct vhost_poll poll[VHOST_NET_VQ_MAX];
+};
+
+static void handle_tx(struct vhost_net *net)
+{
+ struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX];
+ unsigned head, out, in;
+ struct msghdr msg = {
+ .msg_name = NULL,
+ .msg_namelen = 0,
+ .msg_control = NULL,
+ .msg_controllen = 0,
+ .msg_iov = (struct iovec *)vq->iov + 1,
+ .msg_flags = MSG_DONTWAIT,
+ };
+ size_t len;
+ int err;
+ struct socket *sock = rcu_dereference(net->sock);
+ if (!sock || !sock_writeable(sock->sk))
+ return;
+
+ use_mm(net->dev.mm);
+ mutex_lock(&vq->mutex);
+ for (;;) {
+ head = vhost_get_vq_desc(&net->dev, vq, vq->iov, &out, &in);
+ if (head == vq->num)
+ break;
+ if (out <= 1 || in) {
+ vq_err(vq, "Unexpected descriptor format for TX: "
+ "out %d, int %d\n", out, in);
+ break;
+ }
+ /* Sanity check */
+ if (vq->iov->iov_len != sizeof(struct virtio_net_hdr)) {
+ vq_err(vq, "Unexpected header len for TX: "
+ "%ld expected %zd\n", vq->iov->iov_len,
+ sizeof(struct virtio_net_hdr));
+ break;
+ }
+ /* Skip header. TODO: support TSO. */
+ msg.msg_iovlen = out - 1;
+ len = iov_length(vq->iov + 1, out - 1);
+ /* TODO: Check specific error and bomb out unless ENOBUFS? */
+ err = sock->ops->sendmsg(NULL, sock, &msg, len);
+ if (err < 0) {
+ vhost_discard_vq_desc(vq);
+ break;
+ }
+ if (err != len)
+ pr_err("Truncated TX packet: "
+ " len %d != %zd\n", err, len);
+ vhost_add_used_and_trigger(vq, head,
+ len + sizeof(struct virtio_net_hdr));
+ }
+
+ mutex_unlock(&vq->mutex);
+ unuse_mm(net->dev.mm);
+}
+
+static void handle_rx(struct vhost_net *net)
+{
+ struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
+ unsigned head, out, in;
+ struct msghdr msg = {
+ .msg_name = NULL,
+ .msg_namelen = 0,
+ .msg_control = NULL, /* FIXME: get and handle RX aux data. */
+ .msg_controllen = 0,
+ .msg_iov = vq->iov + 1,
+ .msg_flags = MSG_DONTWAIT,
+ };
+
+ struct virtio_net_hdr hdr = {
+ .flags = 0,
+ .gso_type = VIRTIO_NET_HDR_GSO_NONE
+ };
+
+ size_t len;
+ int err;
+ struct socket *sock = rcu_dereference(net->sock);
+ if (!sock || skb_queue_empty(&sock->sk->sk_receive_queue))
+ return;
+
+ use_mm(net->dev.mm);
+ mutex_lock(&vq->mutex);
+
+ for (;;) {
+ head = vhost_get_vq_desc(&net->dev, vq, vq->iov, &out, &in);
+ if (head == vq->num)
+ break;
+ if (in <= 1 || out) {
+ vq_err(vq, "Unexpected descriptor format for RX: out %d, int %d\n",
+ out, in);
+ break;
+ }
+ /* Sanity check */
+ if (vq->iov->iov_len != sizeof(struct virtio_net_hdr)) {
+ vq_err(vq, "Unexpected header len for RX: %ld expected %zd\n",
+ vq->iov->iov_len, sizeof(struct virtio_net_hdr));
+ break;
+ }
+ /* Skip header. TODO: support TSO/mergeable rx buffers. */
+ msg.msg_iovlen = in - 1;
+ len = iov_length(vq->iov + 1, in - 1);
+ err = sock->ops->recvmsg(NULL, sock, &msg,
+ len, MSG_DONTWAIT | MSG_TRUNC);
+ /* TODO: Check specific error and bomb out unless EAGAIN? */
+ if (err < 0) {
+ vhost_discard_vq_desc(vq);
+ break;
+ }
+ /* TODO: Should check and handle checksum. */
+ if (err > len) {
+ pr_err("Discarded truncated rx packet: "
+ " len %d > %zd\n", err, len);
+ vhost_discard_vq_desc(vq);
+ continue;
+ }
+ len = err;
+ err = copy_to_user(vq->iov->iov_base, &hdr, sizeof hdr);
+ if (err) {
+ vq_err(vq, "Unable to write vnet_hdr at addr %p: %d\n",
+ vq->iov->iov_base, err);
+ break;
+ }
+ vhost_add_used_and_trigger(vq, head, len + sizeof hdr);
+ }
+
+ mutex_unlock(&vq->mutex);
+ unuse_mm(net->dev.mm);
+}
+
+static void handle_tx_kick(struct work_struct *work)
+{
+ struct vhost_virtqueue *vq;
+ struct vhost_net *net;
+ vq = container_of(work, struct vhost_virtqueue, poll.work);
+ net = container_of(vq->dev, struct vhost_net, dev);
+ handle_tx(net);
+}
+
+static void handle_rx_kick(struct work_struct *work)
+{
+ struct vhost_virtqueue *vq;
+ struct vhost_net *net;
+ vq = container_of(work, struct vhost_virtqueue, poll.work);
+ net = container_of(vq->dev, struct vhost_net, dev);
+ handle_rx(net);
+}
+
+static void handle_tx_net(struct work_struct *work)
+{
+ struct vhost_net *net;
+ net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_TX].work);
+ handle_tx(net);
+}
+
+static void handle_rx_net(struct work_struct *work)
+{
+ struct vhost_net *net;
+ net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_RX].work);
+ handle_rx(net);
+}
+
+static int vhost_net_open(struct inode *inode, struct file *f)
+{
+ struct vhost_net *n = kzalloc(sizeof *n, GFP_KERNEL);
+ int r;
+ if (!n)
+ return -ENOMEM;
+ f->private_data = n;
+ n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick;
+ n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick;
+ r = vhost_dev_init(&n->dev, n->vqs, VHOST_NET_VQ_MAX);
+ if (r < 0) {
+ kfree(n);
+ return r;
+ }
+
+ vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT);
+ vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN);
+ return 0;
+}
+
+static struct socket *vhost_net_stop(struct vhost_net *n)
+{
+ struct socket *sock = n->sock;
+ rcu_assign_pointer(n->sock, NULL);
+ if (sock) {
+ vhost_poll_flush(n->poll + VHOST_NET_VQ_TX);
+ vhost_poll_flush(n->poll + VHOST_NET_VQ_RX);
+ }
+ return sock;
+}
+
+static int vhost_net_release(struct inode *inode, struct file *f)
+{
+ struct vhost_net *n = f->private_data;
+ struct socket *sock;
+
+ sock = vhost_net_stop(n);
+ vhost_dev_cleanup(&n->dev);
+ if (sock)
+ fput(sock->file);
+ kfree(n);
+ return 0;
+}
+
+static long vhost_net_set_socket(struct vhost_net *n, int fd)
+{
+ struct {
+ struct sockaddr_ll sa;
+ char buf[MAX_ADDR_LEN];
+ } uaddr;
+ struct socket *sock, *oldsock = NULL;
+ int uaddr_len = sizeof uaddr, r;
+
+ mutex_lock(&n->dev.mutex);
+ r = vhost_dev_check_owner(&n->dev);
+ if (r)
+ goto done;
+
+ if (fd == -1) {
+ /* Disconnect from socket and device. */
+ oldsock = vhost_net_stop(n);
+ goto done;
+ }
+
+ sock = sockfd_lookup(fd, &r);
+ if (!sock) {
+ r = -ENOTSOCK;
+ goto done;
+ }
+
+ /* Parameter checking */
+ if (sock->sk->sk_type != SOCK_RAW) {
+ r = -ESOCKTNOSUPPORT;
+ goto done;
+ }
+
+ r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa,
+ &uaddr_len, 0);
+ if (r)
+ goto done;
+
+ if (uaddr.sa.sll_family != AF_PACKET) {
+ r = -EPFNOSUPPORT;
+ goto done;
+ }
+
+ /* start polling new socket */
+ if (sock == oldsock)
+ goto done;
+
+ if (oldsock) {
+ vhost_poll_stop(n->poll + VHOST_NET_VQ_TX);
+ vhost_poll_stop(n->poll + VHOST_NET_VQ_RX);
+ }
+ oldsock = n->sock;
+ rcu_assign_pointer(n->sock, sock);
+ vhost_poll_start(n->poll + VHOST_NET_VQ_TX, sock->file);
+ vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file);
+done:
+ mutex_unlock(&n->dev.mutex);
+ if (oldsock) {
+ vhost_poll_flush(n->poll + VHOST_NET_VQ_TX);
+ vhost_poll_flush(n->poll + VHOST_NET_VQ_RX);
+ vhost_poll_flush(&n->dev.vqs[VHOST_NET_VQ_TX].poll);
+ vhost_poll_flush(&n->dev.vqs[VHOST_NET_VQ_RX].poll);
+ fput(oldsock->file);
+ }
+ return r;
+}
+
+static long vhost_net_reset_owner(struct vhost_net *n)
+{
+ struct socket *sock = NULL;
+ long r;
+ mutex_lock(&n->dev.mutex);
+ r = vhost_dev_check_owner(&n->dev);
+ if (r)
+ goto done;
+ sock = vhost_net_stop(n);
+ r = vhost_dev_reset_owner(&n->dev);
+done:
+ mutex_unlock(&n->dev.mutex);
+ if (sock)
+ fput(sock->file);
+ return r;
+}
+
+static long vhost_net_ioctl(struct file *f, unsigned int ioctl,
+ unsigned long arg)
+{
+ struct vhost_net *n = f->private_data;
+ void __user *argp = (void __user *)arg;
+ u32 __user *featurep = argp;
+ int __user *fdp = argp;
+ u32 features;
+ int fd, r;
+ switch (ioctl) {
+ case VHOST_NET_SET_SOCKET:
+ r = get_user(fd, fdp);
+ if (r < 0)
+ return r;
+ return vhost_net_set_socket(n, fd);
+ case VHOST_GET_FEATURES:
+ /* No features for now */
+ features = 0;
+ return put_user(features, featurep);
+ case VHOST_ACK_FEATURES:
+ r = get_user(features, featurep);
+ /* No features for now */
+ if (r < 0)
+ return r;
+ if (features)
+ return -EOPNOTSUPP;
+ return 0;
+ case VHOST_RESET_OWNER:
+ return vhost_net_reset_owner(n);
+ default:
+ return vhost_dev_ioctl(&n->dev, ioctl, arg);
+ }
+}
+
+static struct file_operations vhost_net_fops = {
+ .owner = THIS_MODULE,
+ .release = vhost_net_release,
+ .unlocked_ioctl = vhost_net_ioctl,
+ .open = vhost_net_open,
+};
+
+static struct miscdevice vhost_net_misc = {
+ VHOST_NET_MINOR,
+ "vhost-net",
+ &vhost_net_fops,
+};
+
+int vhost_net_init(void)
+{
+ int r = vhost_init();
+ if (r)
+ goto err_init;
+ r = misc_register(&vhost_net_misc);
+ if (r)
+ goto err_reg;
+ return 0;
+err_reg:
+ vhost_cleanup();
+err_init:
+ return r;
+
+}
+module_init(vhost_net_init);
+
+void vhost_net_exit(void)
+{
+ misc_deregister(&vhost_net_misc);
+ vhost_cleanup();
+}
+module_exit(vhost_net_exit);
+
+MODULE_VERSION("0.0.1");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Michael S. Tsirkin");
+MODULE_DESCRIPTION("Host kernel accelerator for virtio net");
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
new file mode 100644
index 0000000..6178ec1
--- /dev/null
+++ b/drivers/vhost/vhost.c
@@ -0,0 +1,663 @@
+/* Copyright (C) 2009 Red Hat, Inc.
+ * Copyright (C) 2006 Rusty Russell IBM Corporation
+ *
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ *
+ * Inspiration, some code, and most witty comments come from
+ * Documentation/lguest/lguest.c, by Rusty Russell
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ *
+ * Generic code for virtio server in host kernel.
+ */
+
+#include <linux/eventfd.h>
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+#include <linux/mm.h>
+#include <linux/miscdevice.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/rcupdate.h>
+#include <linux/poll.h>
+#include <linux/file.h>
+
+#include <linux/net.h>
+#include <linux/if_packet.h>
+#include <linux/if_arp.h>
+
+#include <net/sock.h>
+
+#include <asm/mmu_context.h>
+
+#include "vhost.h"
+
+enum {
+ VHOST_MEMORY_MAX_NREGIONS = 64,
+};
+
+struct workqueue_struct *vhost_workqueue;
+
+static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh,
+ poll_table *pt)
+{
+ struct vhost_poll *poll;
+ poll = container_of(pt, struct vhost_poll, table);
+
+ poll->wqh = wqh;
+ add_wait_queue(wqh, &poll->wait);
+}
+
+static int vhost_poll_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
+{
+ struct vhost_poll *poll;
+ poll = container_of(wait, struct vhost_poll, wait);
+ if (!((unsigned long)key & poll->mask))
+ return 0;
+
+ queue_work(vhost_workqueue, &poll->work);
+ return 0;
+}
+
+/* Init poll structure */
+void vhost_poll_init(struct vhost_poll *poll, work_func_t func,
+ unsigned long mask)
+{
+ INIT_WORK(&poll->work, func);
+ init_waitqueue_func_entry(&poll->wait, vhost_poll_wakeup);
+ init_poll_funcptr(&poll->table, vhost_poll_func);
+ poll->mask = mask;
+}
+
+/* Start polling a file. We add ourselves to file's wait queue. The user must
+ * keep a reference to a file until after vhost_poll_stop is called. */
+void vhost_poll_start(struct vhost_poll *poll, struct file *file)
+{
+ unsigned long mask;
+ mask = file->f_op->poll(file, &poll->table);
+ if (mask)
+ vhost_poll_wakeup(&poll->wait, 0, 0, (void *)mask);
+}
+
+/* Stop polling a file. After this function returns, it becomes safe to drop the
+ * file reference. You must also flush afterwards. */
+void vhost_poll_stop(struct vhost_poll *poll)
+{
+ remove_wait_queue(poll->wqh, &poll->wait);
+}
+
+/* Flush any work that has been scheduled. When calling this, don't hold any
+ * locks that are also used by the callback. */
+void vhost_poll_flush(struct vhost_poll *poll)
+{
+ flush_work(&poll->work);
+}
+
+long vhost_dev_init(struct vhost_dev *dev, struct vhost_virtqueue *vqs, int nvqs)
+{
+ int i;
+ dev->vqs = vqs;
+ dev->nvqs = nvqs;
+ mutex_init(&dev->mutex);
+
+ for(i = 0; i < dev->nvqs; ++i) {
+ dev->vqs[i].dev = dev;
+ mutex_init(&dev->vqs[i].mutex);
+ if (dev->vqs[i].handle_kick)
+ vhost_poll_init(&dev->vqs[i].poll,
+ dev->vqs[i].handle_kick,
+ POLLIN);
+ }
+ return 0;
+}
+
+/* User should have device mutex */
+long vhost_dev_check_owner(struct vhost_dev *dev)
+{
+ return dev->mm == current->mm ? 0 : -EPERM;
+}
+
+/* User should have device mutex */
+static long vhost_dev_set_owner(struct vhost_dev *dev)
+{
+ if (dev->mm)
+ return -EBUSY;
+ dev->mm = get_task_mm(current);
+ return 0;
+}
+
+/* User should have device mutex */
+long vhost_dev_reset_owner(struct vhost_dev *dev)
+{
+ struct vhost_memory *memory;
+
+ /* Restore memory to default 1:1 mapping. */
+ memory = kmalloc(offsetof(struct vhost_memory, regions) +
+ 2 * sizeof *memory->regions, GFP_KERNEL);
+ if (!memory)
+ return -ENOMEM;
+
+ vhost_dev_cleanup(dev);
+
+ memory->nregions = 2;
+ memory->regions[0].guest_phys_addr = 1;
+ memory->regions[0].userspace_addr = 1;
+ memory->regions[0].memory_size = ~0ULL;
+ memory->regions[1].guest_phys_addr = 0;
+ memory->regions[1].userspace_addr = 0;
+ memory->regions[1].memory_size = 1;
+ dev->memory = memory;
+ return 0;
+}
+
+/* User should have device mutex */
+void vhost_dev_cleanup(struct vhost_dev *dev)
+{
+ int i;
+ for(i = 0; i < dev->nvqs; ++i) {
+ if (dev->vqs[i].kick && dev->vqs[i].handle_kick) {
+ vhost_poll_stop(&dev->vqs[i].poll);
+ vhost_poll_flush(&dev->vqs[i].poll);
+ }
+ if (dev->vqs[i].error_ctx)
+ eventfd_ctx_put(dev->vqs[i].error_ctx);
+ if (dev->vqs[i].error)
+ fput(dev->vqs[i].error);
+ if (dev->vqs[i].kick)
+ fput(dev->vqs[i].kick);
+ if (dev->vqs[i].call_ctx)
+ eventfd_ctx_put(dev->vqs[i].call_ctx);
+ if (dev->vqs[i].call)
+ fput(dev->vqs[i].call);
+ dev->vqs[i].error_ctx = NULL;
+ dev->vqs[i].error = NULL;
+ dev->vqs[i].kick = NULL;
+ dev->vqs[i].call_ctx = NULL;
+ dev->vqs[i].call = NULL;
+ }
+ /* No one will access memory at this point */
+ kfree(dev->memory);
+ dev->memory = NULL;
+ if (dev->mm)
+ mmput(dev->mm);
+ dev->mm = NULL;
+}
+
+static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
+{
+ struct vhost_memory mem, *newmem, *oldmem;
+ unsigned long size = offsetof(struct vhost_memory, regions);
+ long r;
+ r = copy_from_user(&mem, m, size);
+ if (r)
+ return r;
+ if (mem.padding)
+ return -EOPNOTSUPP;
+ if (mem.nregions > VHOST_MEMORY_MAX_NREGIONS)
+ return -E2BIG;
+ newmem = kmalloc(size + mem.nregions * sizeof *m->regions, GFP_KERNEL);
+ if (!newmem)
+ return -ENOMEM;
+
+ memcpy(newmem, &mem, size);
+ r = copy_from_user(newmem->regions, m->regions,
+ mem.nregions * sizeof *m->regions);
+ if (r) {
+ kfree(newmem);
+ return r;
+ }
+ oldmem = d->memory;
+ rcu_assign_pointer(d->memory, newmem);
+ synchronize_rcu();
+ kfree(oldmem);
+ return 0;
+}
+
+static int init_used(struct vhost_virtqueue *vq)
+{
+ u16 flags = 0;
+ int r = put_user(flags, &vq->used->flags);
+ if (r)
+ return r;
+ return get_user(vq->last_used_idx, &vq->used->idx);
+}
+
+static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp)
+{
+ struct file *eventfp, *filep = NULL, *pollstart = NULL, *pollstop = NULL;
+ struct eventfd_ctx *ctx = NULL;
+ u32 __user *idxp = argp;
+ struct vhost_virtqueue *vq;
+ struct vhost_vring_state s;
+ struct vhost_vring_file f;
+ struct vhost_vring_addr a;
+ u32 idx;
+ long r;
+
+ r = get_user(idx, idxp);
+ if (r < 0)
+ return r;
+ if (idx > d->nvqs)
+ return -ENOBUFS;
+
+ vq = d->vqs + idx;
+
+ mutex_lock(&vq->mutex);
+
+ switch (ioctl) {
+ case VHOST_SET_VRING_NUM:
+ r = copy_from_user(&s, argp, sizeof s);
+ if (r < 0)
+ break;
+ if (s.num > 0xffff) {
+ r = -EINVAL;
+ break;
+ }
+ vq->num = s.num;
+ break;
+ case VHOST_SET_VRING_BASE:
+ r = copy_from_user(&s, argp, sizeof s);
+ if (r < 0)
+ break;
+ if (s.num > 0xffff) {
+ r = -EINVAL;
+ break;
+ }
+ vq->last_avail_idx = s.num;
+ break;
+ case VHOST_GET_VRING_BASE:
+ s.index = idx;
+ s.num = vq->last_avail_idx;
+ r = copy_to_user(argp, &s, sizeof s);
+ break;
+ case VHOST_SET_VRING_DESC:
+ r = copy_from_user(&a, argp, sizeof a);
+ if (r < 0)
+ break;
+ if (a.padding) {
+ r = -EOPNOTSUPP;
+ break;
+ }
+ if ((u64)(long)a.user_addr != a.user_addr) {
+ r = -EFAULT;
+ break;
+ }
+ vq->desc = (void __user *)(long)a.user_addr;
+ break;
+ case VHOST_SET_VRING_AVAIL:
+ r = copy_from_user(&a, argp, sizeof a);
+ if (r < 0)
+ break;
+ if (a.padding) {
+ r = -EOPNOTSUPP;
+ break;
+ }
+ if ((u64)(long)a.user_addr != a.user_addr) {
+ r = -EFAULT;
+ break;
+ }
+ vq->avail = (void __user *)(long)a.user_addr;
+ break;
+ case VHOST_SET_VRING_USED:
+ r = copy_from_user(&a, argp, sizeof a);
+ if (r < 0)
+ break;
+ if (a.padding) {
+ r = -EOPNOTSUPP;
+ break;
+ }
+ if ((u64)(long)a.user_addr != a.user_addr) {
+ r = -EFAULT;
+ break;
+ }
+ vq->used = (void __user *)(long)a.user_addr;
+ r = init_used(vq);
+ if (r)
+ break;
+ break;
+ case VHOST_SET_VRING_KICK:
+ r = copy_from_user(&f, argp, sizeof f);
+ if (r < 0)
+ break;
+ eventfp = f.fd == -1 ? NULL: eventfd_fget(f.fd);
+ if (IS_ERR(eventfp))
+ return PTR_ERR(eventfp);
+ if (eventfp != vq->kick) {
+ pollstop = filep = vq->kick;
+ pollstart = vq->kick = eventfp;
+ } else
+ filep = eventfp;
+ break;
+ case VHOST_SET_VRING_CALL:
+ r = copy_from_user(&f, argp, sizeof f);
+ if (r < 0)
+ break;
+ eventfp = f.fd == -1 ? NULL: eventfd_fget(f.fd);
+ if (IS_ERR(eventfp))
+ return PTR_ERR(eventfp);
+ if (eventfp != vq->call) {
+ filep = vq->call;
+ ctx = vq->call_ctx;
+ vq->call = eventfp;
+ vq->call_ctx = eventfp ?
+ eventfd_ctx_fileget(eventfp) : NULL;
+ } else
+ filep = eventfp;
+ break;
+ case VHOST_SET_VRING_ERR:
+ r = copy_from_user(&f, argp, sizeof f);
+ if (r < 0)
+ break;
+ eventfp = f.fd == -1 ? NULL: eventfd_fget(f.fd);
+ if (IS_ERR(eventfp))
+ return PTR_ERR(eventfp);
+ if (eventfp != vq->error) {
+ filep = vq->error;
+ vq->error = eventfp;
+ ctx = vq->error_ctx;
+ vq->error_ctx = eventfp ?
+ eventfd_ctx_fileget(eventfp) : NULL;
+ } else
+ filep = eventfp;
+ break;
+ default:
+ r = -ENOTTY;
+ }
+
+ if (pollstop && vq->handle_kick)
+ vhost_poll_stop(&vq->poll);
+
+ if (ctx)
+ eventfd_ctx_put(ctx);
+ if (filep)
+ fput(filep);
+
+ if (pollstart && vq->handle_kick)
+ vhost_poll_start(&vq->poll, vq->kick);
+
+ mutex_unlock(&vq->mutex);
+
+ if (pollstop && vq->handle_kick)
+ vhost_poll_flush(&vq->poll);
+ return 0;
+}
+
+long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ long r;
+
+ mutex_lock(&d->mutex);
+ if (ioctl == VHOST_SET_OWNER) {
+ r = vhost_dev_set_owner(d);
+ goto done;
+ }
+
+ r = vhost_dev_check_owner(d);
+ if (r)
+ goto done;
+
+ switch (ioctl) {
+ case VHOST_SET_MEM_TABLE:
+ r = vhost_set_memory(d, argp);
+ break;
+ default:
+ r = vhost_set_vring(d, ioctl, argp);
+ break;
+ }
+done:
+ mutex_unlock(&d->mutex);
+ return r;
+}
+
+static const struct vhost_memory_region *find_region(struct vhost_memory *mem,
+ __u64 addr, __u32 len)
+{
+ struct vhost_memory_region *reg;
+ int i;
+ /* linear search is not brilliant, but we really have on the order of 6
+ * regions in practice */
+ for (i = 0; i < mem->nregions; ++i) {
+ reg = mem->regions + i;
+ if (reg->guest_phys_addr <= addr &&
+ reg->guest_phys_addr + reg->memory_size - 1 >= addr)
+ return reg;
+ }
+ return NULL;
+}
+
+/* FIXME: this does not handle a region that spans multiple
+ * address/len pairs */
+int translate_desc(struct vhost_dev *dev, u64 addr, u32 len,
+ struct iovec iov[], int iov_count, int iov_size,
+ unsigned *num)
+{
+ const struct vhost_memory_region *reg;
+ struct vhost_memory *mem;
+ struct iovec *_iov;
+ u64 s = 0;
+ int ret = 0;
+
+ rcu_read_lock();
+
+ mem = rcu_dereference(dev->memory);
+ while ((u64)len > s) {
+ u64 size;
+ if (*num + iov_count >= iov_size) {
+ ret = -ENOBUFS;
+ break;
+ }
+ reg = find_region(mem, addr, len);
+ if (!reg) {
+ ret = -EFAULT;
+ break;
+ }
+ _iov = iov + iov_count + *num;
+ size = reg->memory_size - addr + reg->guest_phys_addr;
+ _iov->iov_len = min((u64)len, size);
+ _iov->iov_base = (void *)
+ (reg->userspace_addr + addr - reg->guest_phys_addr);
+ s += size;
+ addr += size;
+ ++*num;
+ }
+
+ rcu_read_unlock();
+ return ret;
+}
+
+/* Each buffer in the virtqueues is actually a chain of descriptors. This
+ * function returns the next descriptor in the chain, or vq->vring.num if we're
+ * at the end. */
+static unsigned next_desc(struct vhost_virtqueue *vq, struct vring_desc *desc)
+{
+ unsigned int next;
+
+ /* If this descriptor says it doesn't chain, we're done. */
+ if (!(desc->flags & VRING_DESC_F_NEXT))
+ return vq->num;
+
+ /* Check they're not leading us off end of descriptors. */
+ next = desc->next;
+ /* Make sure compiler knows to grab that: we don't want it changing! */
+ /* We will use the result as an index in an array, so most
+ * architectures only need a compiler barrier here. */
+ read_barrier_depends();
+
+ if (next >= vq->num) {
+ vq_err(vq, "Desc next is %u > %u", next, vq->num);
+ return vq->num;
+ }
+
+ return next;
+}
+
+/* This looks in the virtqueue and for the first available buffer, and converts
+ * it to an iovec for convenient access. Since descriptors consist of some
+ * number of output then some number of input descriptors, it's actually two
+ * iovecs, but we pack them into one and note how many of each there were.
+ *
+ * This function returns the descriptor number found, or vq->num (which
+ * is never a valid descriptor number) if none was found. */
+unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
+ struct iovec iov[],
+ unsigned int *out_num, unsigned int *in_num)
+{
+ struct vring_desc desc;
+ unsigned int i, head;
+ u16 last_avail_idx, idx;
+
+ /* Check it isn't doing very strange things with descriptor numbers. */
+ last_avail_idx = vq->last_avail_idx;
+ if (get_user(idx, &vq->avail->idx)) {
+ vq_err(vq, "Failed to access avail idx at %p\n",
+ &vq->avail->idx);
+ return vq->num;
+ }
+
+ if ((u16)(idx - last_avail_idx) > vq->num) {
+ vq_err(vq, "Guest moved used index from %u to %u",
+ last_avail_idx, idx);
+ return vq->num;
+ }
+
+ /* If there's nothing new since last we looked, return invalid. */
+ if (idx == last_avail_idx)
+ return vq->num;
+
+ /* Grab the next descriptor number they're advertising, and increment
+ * the index we've seen. */
+ if (get_user(head, &vq->avail->ring[last_avail_idx % vq->num])) {
+ vq_err(vq, "Failed to read head: idx %d address %p\n",
+ idx, &vq->avail->ring[last_avail_idx % vq->num]);
+ return vq->num;
+ }
+
+ /* If their number is silly, that's a fatal mistake. */
+ if (head >= vq->num) {
+ vq_err(vq, "Guest says index %u > %u is available",
+ head, vq->num);
+ return vq->num;
+ }
+
+ vq->last_avail_idx++;
+
+ /* When we start there are none of either input nor output. */
+ *out_num = *in_num = 0;
+
+ i = head;
+ do {
+ unsigned *num;
+ unsigned iov_count;
+ if (copy_from_user(&desc, vq->desc + i, sizeof desc)) {
+ vq_err(vq, "Failed to get descriptor: idx %d addr %p\n",
+ i, vq->desc + i);
+ return vq->num;
+ }
+ /* If this is an input descriptor, increment that count. */
+ if (desc.flags & VRING_DESC_F_WRITE) {
+ num = in_num;
+ iov_count = *out_num;
+ } else {
+ /* If it's an output descriptor, they're all supposed
+ * to come before any input descriptors. */
+ if (*in_num) {
+ vq_err(vq, "Descriptor has out after in: "
+ "idx %d\n", i);
+ return vq->num;
+ }
+ num = out_num;
+ iov_count = *in_num;
+ }
+ if (translate_desc(dev, desc.addr, desc.len, iov, iov_count,
+ VHOST_NET_MAX_SG, num)) {
+ vq_err(vq, "Failed to translate descriptor: idx %d\n",
+ i);
+ return vq->num;
+ }
+
+ /* If we've got too many, that implies a descriptor loop. */
+ if (*out_num + *in_num > vq->num) {
+ vq_err(vq, "Looped descriptor: idx %d\n", i);
+ return vq->num;
+ }
+ } while ((i = next_desc(vq, &desc)) != vq->num);
+
+ vq->inflight++;
+ return head;
+}
+
+/* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */
+void vhost_discard_vq_desc(struct vhost_virtqueue *vq)
+{
+ vq->last_avail_idx--;
+ vq->inflight--;
+}
+
+/* After we've used one of their buffers, we tell them about it. We'll then
+ * want to send them an interrupt, using vq->call. */
+int vhost_add_used(struct vhost_virtqueue *vq,
+ unsigned int head, int len)
+{
+ struct vring_used_elem *used;
+
+ /* The virtqueue contains a ring of used buffers. Get a pointer to the
+ * next entry in that used ring. */
+ used = &vq->used->ring[vq->last_used_idx % vq->num];
+ if (put_user(head, &used->id)) {
+ vq_err(vq, "Failed to write used id");
+ return -EFAULT;
+ }
+ if (put_user(len, &used->len)) {
+ vq_err(vq, "Failed to write used len");
+ return -EFAULT;
+ }
+ /* Make sure buffer is written before we update index. */
+ wmb();
+ if (put_user(vq->last_used_idx + 1, &vq->used->idx)) {
+ vq_err(vq, "Failed to increment used idx");
+ return -EFAULT;
+ }
+ vq->last_used_idx++;
+ vq->inflight--;
+ return 0;
+}
+
+/* This actually sends the interrupt for this virtqueue */
+void vhost_trigger_irq(struct vhost_virtqueue *vq)
+{
+ __u16 flags = 0;
+ if (get_user(flags, &vq->avail->flags)) {
+ vq_err(vq, "Failed to get flags");
+ return;
+ }
+
+ /* If they don't want an interrupt, don't send one, unless empty. */
+ if ((flags & VRING_AVAIL_F_NO_INTERRUPT) && vq->inflight)
+ return;
+
+ /* Send the Guest an interrupt tell them we used something up. */
+ if (vq->call_ctx)
+ eventfd_signal(vq->call_ctx, 1);
+}
+
+/* And here's the combo meal deal. Supersize me! */
+void vhost_add_used_and_trigger(struct vhost_virtqueue *vq,
+ unsigned int head, int len)
+{
+ vhost_add_used(vq, head, len);
+ vhost_trigger_irq(vq);
+}
+
+int vhost_init(void)
+{
+ vhost_workqueue = create_workqueue("vhost");
+ if (!vhost_workqueue)
+ return -ENOMEM;
+ return 0;
+}
+
+void vhost_cleanup(void)
+{
+ destroy_workqueue(vhost_workqueue);
+}
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
new file mode 100644
index 0000000..7f7ffcd
--- /dev/null
+++ b/drivers/vhost/vhost.h
@@ -0,0 +1,108 @@
+#ifndef _VHOST_H
+#define _VHOST_H
+
+#include <linux/eventfd.h>
+#include <linux/vhost.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/poll.h>
+#include <linux/file.h>
+#include <linux/skbuff.h>
+
+struct vhost_device;
+
+enum {
+ VHOST_NET_MAX_SG = MAX_SKB_FRAGS + 2,
+};
+
+/* Poll a file (eventfd or socket) */
+/* Note: there's nothing vhost specific about this structure. */
+struct vhost_poll {
+ poll_table table;
+ wait_queue_head_t *wqh;
+ wait_queue_t wait;
+ /* struct which will handle all actual work. */
+ struct work_struct work;
+ unsigned long mask;
+};
+
+void vhost_poll_init(struct vhost_poll *poll, work_func_t func,
+ unsigned long mask);
+void vhost_poll_start(struct vhost_poll *poll, struct file *file);
+void vhost_poll_stop(struct vhost_poll *poll);
+void vhost_poll_flush(struct vhost_poll *poll);
+
+/* The virtqueue structure describes a queue attached to a device. */
+struct vhost_virtqueue {
+ struct vhost_dev *dev;
+
+ /* The actual ring of buffers. */
+ struct mutex mutex;
+ unsigned int num;
+ struct vring_desc __user *desc;
+ struct vring_avail __user *avail;
+ struct vring_used __user *used;
+ struct file *kick;
+ struct file *call;
+ struct file *error;
+ struct eventfd_ctx *call_ctx;
+ struct eventfd_ctx *error_ctx;
+
+ struct vhost_poll poll;
+
+ /* The routine to call when the Guest pings us, or timeout. */
+ work_func_t handle_kick;
+
+ /* Last available index we saw. */
+ u16 last_avail_idx;
+
+ /* Last index we used. */
+ u16 last_used_idx;
+
+ /* Outstanding buffers */
+ unsigned int inflight;
+
+ /* Is this blocked? */
+ bool blocked;
+
+ struct iovec iov[VHOST_NET_MAX_SG];
+
+} ____cacheline_aligned;
+
+struct vhost_dev {
+ /* Readers use RCU to access memory table pointer.
+ * Writers use mutex below.*/
+ struct vhost_memory *memory;
+ struct mm_struct *mm;
+ struct vhost_virtqueue *vqs;
+ int nvqs;
+ struct mutex mutex;
+};
+
+long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue *vqs, int nvqs);
+long vhost_dev_check_owner(struct vhost_dev *);
+long vhost_dev_reset_owner(struct vhost_dev *);
+void vhost_dev_cleanup(struct vhost_dev *);
+long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, unsigned long arg);
+
+unsigned vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
+ struct iovec iov[],
+ unsigned int *out_num, unsigned int *in_num);
+void vhost_discard_vq_desc(struct vhost_virtqueue *);
+
+int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
+void vhost_trigger_irq(struct vhost_virtqueue *);
+void vhost_add_used_and_trigger(struct vhost_virtqueue *,
+ unsigned int head, int len);
+
+int vhost_init(void);
+void vhost_cleanup(void);
+
+#define vq_err(vq, fmt, ...) do { \
+ printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__); \
+ if ((vq)->error_ctx) \
+ eventfd_signal((vq)->error_ctx, 1);\
+ } while (0)
+
+#endif
diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index dec2f18..975df9a 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -360,6 +360,7 @@ unifdef-y += uio.h
unifdef-y += unistd.h
unifdef-y += usbdevice_fs.h
unifdef-y += utsname.h
+unifdef-y += vhost.h
unifdef-y += videodev2.h
unifdef-y += videodev.h
unifdef-y += virtio_config.h
diff --git a/include/linux/miscdevice.h b/include/linux/miscdevice.h
index 0521177..781a8bb 100644
--- a/include/linux/miscdevice.h
+++ b/include/linux/miscdevice.h
@@ -30,6 +30,7 @@
#define HPET_MINOR 228
#define FUSE_MINOR 229
#define KVM_MINOR 232
+#define VHOST_NET_MINOR 233
#define MISC_DYNAMIC_MINOR 255
struct device;
diff --git a/include/linux/vhost.h b/include/linux/vhost.h
new file mode 100644
index 0000000..9ec6d5f
--- /dev/null
+++ b/include/linux/vhost.h
@@ -0,0 +1,100 @@
+#ifndef _LINUX_VHOST_H
+#define _LINUX_VHOST_H
+/* Userspace interface for in-kernel virtio accelerators. */
+
+/* vhost is used to reduce the number of system calls involved in virtio.
+ *
+ * Existing virtio net code is used in the guest without modification.
+ *
+ * This header includes interface used by userspace hypervisor for
+ * device configuration.
+ */
+
+#include <linux/types.h>
+#include <linux/compiler.h>
+#include <linux/ioctl.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_ring.h>
+
+struct vhost_vring_state {
+ unsigned int index;
+ unsigned int num;
+};
+
+struct vhost_vring_file {
+ unsigned int index;
+ int fd;
+};
+
+struct vhost_vring_addr {
+ unsigned int index;
+ unsigned int padding;
+ __u64 user_addr;
+};
+
+struct vhost_memory_region {
+ __u64 guest_phys_addr;
+ __u64 memory_size; /* bytes */
+ __u64 userspace_addr;
+ __u64 padding; /* read/write protection? */
+};
+
+struct vhost_memory {
+ __u32 nregions;
+ __u32 padding;
+ struct vhost_memory_region regions[0];
+};
+
+/* ioctls */
+
+#define VHOST_VIRTIO 0xAF
+
+/* Features bitmask for forward compatibility. Transport bits must be zero. */
+#define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u32)
+#define VHOST_ACK_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u32)
+
+/* Set current process as the (exclusive) owner of this file descriptor. This
+ * must be called before any other vhost command. Further calls to
+ * VHOST_OWNER_SET fail until VHOST_OWNER_RESET is called. */
+#define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01)
+/* Give up ownership, and reset the device to default values.
+ * Allows subsequent call to VHOST_OWNER_SET to succeed. */
+#define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02)
+
+/* Set up/modify memory layout */
+#define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory)
+
+/* Ring setup. These parameters can not be modified while ring is running
+ * (bound to a device). */
+/* Set number of descriptors in ring */
+#define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state)
+/* Start of array of descriptors (virtually contiguous) */
+#define VHOST_SET_VRING_DESC _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr)
+/* Used structure address */
+#define VHOST_SET_VRING_USED _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_addr)
+/* Available structure address */
+#define VHOST_SET_VRING_AVAIL _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_addr)
+/* Base value where queue looks for available descriptors */
+#define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state)
+/* Get accessor: reads index, writes value in num */
+#define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x14, struct vhost_vring_state)
+
+/* The following ioctls use eventfd file descriptors to signal and poll
+ * for events. */
+
+/* Set eventfd to poll for added buffers */
+#define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file)
+/* Set eventfd to signal when buffers have beed used */
+#define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file)
+/* Set eventfd to signal an error */
+#define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
+
+/* VHOST_NET specific defines */
+
+/* Attach virtio net device to a raw socket. The socket must be already
+ * bound to an ethernet device, this device will be used for transmit.
+ * Pass -1 to unbind from the socket and the transmit device.
+ * This can be used to stop the device (e.g. for migration). */
+#define VHOST_NET_SET_SOCKET _IOW(VHOST_VIRTIO, 0x30, int)
+
+#endif
--
1.6.2.5
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* [PATCHv2 1/2] mm: export use_mm/unuse_mm to modules
From: Michael S. Tsirkin @ 2009-08-11 21:27 UTC (permalink / raw)
To: netdev, virtualization, kvm, linux-kernel, mingo, linux-mm, akpm
In-Reply-To: <cover.1249992497.git.mst@redhat.com>
vhost net module wants to do copy to/from user from a kernel thread,
which needs use_mm (like what fs/aio has). Move that into mm/ and
export to modules.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
fs/aio.c | 47 +----------------------------------
include/linux/mmu_context.h | 9 ++++++
mm/Makefile | 2 +-
mm/mmu_context.c | 58 +++++++++++++++++++++++++++++++++++++++++++
4 files changed, 69 insertions(+), 47 deletions(-)
create mode 100644 include/linux/mmu_context.h
create mode 100644 mm/mmu_context.c
diff --git a/fs/aio.c b/fs/aio.c
index d065b2c..fc21c23 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -24,6 +24,7 @@
#include <linux/file.h>
#include <linux/mm.h>
#include <linux/mman.h>
+#include <linux/mmu_context.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <linux/aio.h>
@@ -34,7 +35,6 @@
#include <asm/kmap_types.h>
#include <asm/uaccess.h>
-#include <asm/mmu_context.h>
#if DEBUG > 1
#define dprintk printk
@@ -595,51 +595,6 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id)
}
/*
- * use_mm
- * Makes the calling kernel thread take on the specified
- * mm context.
- * Called by the retry thread execute retries within the
- * iocb issuer's mm context, so that copy_from/to_user
- * operations work seamlessly for aio.
- * (Note: this routine is intended to be called only
- * from a kernel thread context)
- */
-static void use_mm(struct mm_struct *mm)
-{
- struct mm_struct *active_mm;
- struct task_struct *tsk = current;
-
- task_lock(tsk);
- active_mm = tsk->active_mm;
- atomic_inc(&mm->mm_count);
- tsk->mm = mm;
- tsk->active_mm = mm;
- switch_mm(active_mm, mm, tsk);
- task_unlock(tsk);
-
- mmdrop(active_mm);
-}
-
-/*
- * unuse_mm
- * Reverses the effect of use_mm, i.e. releases the
- * specified mm context which was earlier taken on
- * by the calling kernel thread
- * (Note: this routine is intended to be called only
- * from a kernel thread context)
- */
-static void unuse_mm(struct mm_struct *mm)
-{
- struct task_struct *tsk = current;
-
- task_lock(tsk);
- tsk->mm = NULL;
- /* active_mm is still 'mm' */
- enter_lazy_tlb(mm, tsk);
- task_unlock(tsk);
-}
-
-/*
* Queue up a kiocb to be retried. Assumes that the kiocb
* has already been marked as kicked, and places it on
* the retry run list for the corresponding ioctx, if it
diff --git a/include/linux/mmu_context.h b/include/linux/mmu_context.h
new file mode 100644
index 0000000..70fffeb
--- /dev/null
+++ b/include/linux/mmu_context.h
@@ -0,0 +1,9 @@
+#ifndef _LINUX_MMU_CONTEXT_H
+#define _LINUX_MMU_CONTEXT_H
+
+struct mm_struct;
+
+void use_mm(struct mm_struct *mm);
+void unuse_mm(struct mm_struct *mm);
+
+#endif
diff --git a/mm/Makefile b/mm/Makefile
index 5e0bd64..46c3892 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -11,7 +11,7 @@ obj-y := bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \
maccess.o page_alloc.o page-writeback.o pdflush.o \
readahead.o swap.o truncate.o vmscan.o shmem.o \
prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \
- page_isolation.o mm_init.o $(mmu-y)
+ page_isolation.o mm_init.o mmu_context.o $(mmu-y)
obj-y += init-mm.o
obj-$(CONFIG_PROC_PAGE_MONITOR) += pagewalk.o
diff --git a/mm/mmu_context.c b/mm/mmu_context.c
new file mode 100644
index 0000000..9989c2f
--- /dev/null
+++ b/mm/mmu_context.c
@@ -0,0 +1,58 @@
+/* Copyright (C) 2009 Red Hat, Inc.
+ *
+ * See ../COPYING for licensing terms.
+ */
+
+#include <linux/mm.h>
+#include <linux/mmu_context.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+
+#include <asm/mmu_context.h>
+
+/*
+ * use_mm
+ * Makes the calling kernel thread take on the specified
+ * mm context.
+ * Called by the retry thread execute retries within the
+ * iocb issuer's mm context, so that copy_from/to_user
+ * operations work seamlessly for aio.
+ * (Note: this routine is intended to be called only
+ * from a kernel thread context)
+ */
+void use_mm(struct mm_struct *mm)
+{
+ struct mm_struct *active_mm;
+ struct task_struct *tsk = current;
+
+ task_lock(tsk);
+ active_mm = tsk->active_mm;
+ atomic_inc(&mm->mm_count);
+ tsk->mm = mm;
+ tsk->active_mm = mm;
+ switch_mm(active_mm, mm, tsk);
+ task_unlock(tsk);
+
+ mmdrop(active_mm);
+}
+EXPORT_SYMBOL_GPL(use_mm);
+
+/*
+ * unuse_mm
+ * Reverses the effect of use_mm, i.e. releases the
+ * specified mm context which was earlier taken on
+ * by the calling kernel thread
+ * (Note: this routine is intended to be called only
+ * from a kernel thread context)
+ */
+void unuse_mm(struct mm_struct *mm)
+{
+ struct task_struct *tsk = current;
+
+ task_lock(tsk);
+ tsk->mm = NULL;
+ /* active_mm is still 'mm' */
+ enter_lazy_tlb(mm, tsk);
+ task_unlock(tsk);
+}
+EXPORT_SYMBOL_GPL(unuse_mm);
--
1.6.2.5
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* [PATCHv2 0/2] vhost: a kernel-level virtio server
From: Michael S. Tsirkin @ 2009-08-11 21:27 UTC (permalink / raw)
To: netdev, virtualization, kvm, linux-kernel, mingo, linux-mm, akpm
This implements vhost: a kernel-level backend for virtio,
The main motivation for this work is to reduce virtualization
overhead for virtio by removing system calls on data path,
without guest changes. For virtio-net, this removes up to
4 system calls per packet: vm exit for kick, reentry for kick,
iothread wakeup for packet, interrupt injection for packet.
Some more detailed description attached to the patch itself.
The patches are against 2.6.31-rc4. I'd like them to go into linux-next
and down the road 2.6.32 if possible. Please comment.
Changes from v1:
- Move use_mm/unuse_mm from fs/aio.c to mm instead of copying.
- Reorder code to avoid need for forward declarations
- Kill a couple of debugging printks
Michael S. Tsirkin (2):
mm: export use_mm/unuse_mm to modules
vhost_net: a kernel-level virtio server
MAINTAINERS | 10 +
arch/x86/kvm/Kconfig | 1 +
drivers/Makefile | 1 +
drivers/vhost/Kconfig | 11 +
drivers/vhost/Makefile | 2 +
drivers/vhost/net.c | 411 +++++++++++++++++++++++++++
drivers/vhost/vhost.c | 663 +++++++++++++++++++++++++++++++++++++++++++
drivers/vhost/vhost.h | 108 +++++++
fs/aio.c | 47 +---
include/linux/Kbuild | 1 +
include/linux/miscdevice.h | 1 +
include/linux/mmu_context.h | 9 +
include/linux/vhost.h | 100 +++++++
mm/Makefile | 2 +-
mm/mmu_context.c | 58 ++++
15 files changed, 1378 insertions(+), 47 deletions(-)
create mode 100644 drivers/vhost/Kconfig
create mode 100644 drivers/vhost/Makefile
create mode 100644 drivers/vhost/net.c
create mode 100644 drivers/vhost/vhost.c
create mode 100644 drivers/vhost/vhost.h
create mode 100644 include/linux/mmu_context.h
create mode 100644 include/linux/vhost.h
create mode 100644 mm/mmu_context.c
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^ permalink raw reply
* Re: [PATCH 1/2] mac802154: add a software MAC 802.15.4 implementation
From: Johannes Berg @ 2009-08-11 20:39 UTC (permalink / raw)
To: Dmitry Eremin-Solenikov; +Cc: netdev, linux-wireless, Sergey Lapin
In-Reply-To: <20090811202304.GA6303@doriath.ww600.siemens.net>
[-- Attachment #1: Type: text/plain, Size: 2215 bytes --]
On Wed, 2009-08-12 at 00:23 +0400, Dmitry Eremin-Solenikov wrote:
> > That return value is strange.
>
> The idea is that tx function can return info about errors during
> transmit (busy channel, no ACK, etc).
Well, TX functions don't usually wait for anything so busy channel or no
ack wouldn't be possible to return there but more like a TX status, and
I think people are more used to NETDEV_TX_OK etc. return values. But
it's your choice to make, obviously. If you want to return specific
information like that though I would recommend making an enum so you get
at least some type checking (and things like 'return -1' are more
obviously wrong).
> > We've had no end to trouble with the master netdev, I suggest you look
> > into the current mac80211 code and see if you can get rid of it.
>
> What troubles w/ master netdev did you have had? I do still see the
> master devices in mac80211. IIUC, it's planned to replace (from
> management point of view) the mdev with wiphy instance, isn't it?
Mostly the userspace API was a mess, and you can't actually _do_
anything with the master netdev. It also doesn't see all the frames,
only outgoing. It's very strange.
Yes, you still see it in the current tree, but it's gone in our -next
tree.
The biggest problem is that it really clutters up the userspace API
since you can't do any netdev things with it, it's just a placeholder.
In addition to that, you can't put anything into skb->cb, then push the
frame to the master netdev, and expect things in skb->cb to still be
there when the frame arrives at the master netdev. Not sure you do that
(I hope not because that would be very buggy), but eventually you'll
probably find that you do want that, etc.
IMHO it's just better practise to not use it in situations like this
where it can't be really used as a netdev.
> Hmm. I thought that one may be able to rmmod the module w/ ops while the
> device is still hanging in the system. On the other hand, ops are
> provided by the driver, so if one rmmods the driver and the device is
> still there, it's a bug...
Exactly. You _want_ to be able to rmmod the module and have it
unregister itself.
johannes
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^ permalink raw reply
* Re: [RFC PATCH v2 2/2] selinux: Support for the new TUN LSM hooks
From: Eric Paris @ 2009-08-11 20:36 UTC (permalink / raw)
To: Paul Moore; +Cc: linux-security-module, netdev, selinux
In-Reply-To: <20090810172850.7946.25175.stgit@flek.lan>
On Mon, Aug 10, 2009 at 1:28 PM, Paul Moore<paul.moore@hp.com> wrote:
> Add support for the new TUN LSM hooks: security_tun_dev_create(),
> security_tun_dev_post_create() and security_tun_dev_attach(). This includes
> the addition of a new object class, tun_socket, which represents the socks
> associated with TUN devices. The _tun_dev_create() and _tun_dev_post_create()
> hooks are fairly similar to the standard socket functions but _tun_dev_attach()
> is a bit special. The _tun_dev_attach() is unique because it involves a
> domain attaching to an existing TUN device and its associated tun_socket
> object, an operation which does not exist with standard sockets and most
> closely resembles a relabel operation.
Looks good to me, feel free to add my Ack
-Eric
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^ permalink raw reply
* Re: [RFC PATCH v2 1/2] lsm: Add hooks to the TUN driver
From: Eric Paris @ 2009-08-11 20:34 UTC (permalink / raw)
To: Paul Moore; +Cc: linux-security-module, netdev, selinux
In-Reply-To: <20090810172844.7946.43287.stgit@flek.lan>
On Mon, Aug 10, 2009 at 1:28 PM, Paul Moore<paul.moore@hp.com> wrote:
> The TUN driver lacks any LSM hooks which makes it difficult for LSM modules,
> such as SELinux, to enforce access controls on network traffic generated by
> TUN users; this is particularly problematic for virtualization apps such as
> QEMU and KVM. This patch adds three new LSM hooks designed to control the
> creation and attachment of TUN devices, the hooks are:
>
> * security_tun_dev_create()
> Provides access control for the creation of new TUN devices
>
> * security_tun_dev_post_create()
> Provides the ability to create the necessary socket LSM state for newly
> created TUN devices
>
> * security_tun_dev_attach()
> Provides access control for attaching to existing, persistent TUN devices
> and the ability to update the TUN device's socket LSM state as necessary
Looks good to me, feel free to add my Ack.
-Eric
> ---
>
> drivers/net/tun.c | 22 +++++++++++++++-------
> include/linux/security.h | 31 +++++++++++++++++++++++++++++++
> security/capability.c | 19 +++++++++++++++++++
> security/security.c | 18 ++++++++++++++++++
> 4 files changed, 83 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> index 027f7ab..e6667ce 100644
> --- a/drivers/net/tun.c
> +++ b/drivers/net/tun.c
> @@ -130,17 +130,10 @@ static inline struct tun_sock *tun_sk(struct sock *sk)
> static int tun_attach(struct tun_struct *tun, struct file *file)
> {
> struct tun_file *tfile = file->private_data;
> - const struct cred *cred = current_cred();
> int err;
>
> ASSERT_RTNL();
>
> - /* Check permissions */
> - if (((tun->owner != -1 && cred->euid != tun->owner) ||
> - (tun->group != -1 && !in_egroup_p(tun->group))) &&
> - !capable(CAP_NET_ADMIN))
> - return -EPERM;
> -
> netif_tx_lock_bh(tun->dev);
>
> err = -EINVAL;
> @@ -926,6 +919,8 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
>
> dev = __dev_get_by_name(net, ifr->ifr_name);
> if (dev) {
> + const struct cred *cred = current_cred();
> +
> if (ifr->ifr_flags & IFF_TUN_EXCL)
> return -EBUSY;
> if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
> @@ -935,6 +930,14 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
> else
> return -EINVAL;
>
> + if (((tun->owner != -1 && cred->euid != tun->owner) ||
> + (tun->group != -1 && !in_egroup_p(tun->group))) &&
> + !capable(CAP_NET_ADMIN))
> + return -EPERM;
> + err = security_tun_dev_attach(tun->sk);
> + if (err < 0)
> + return err;
> +
> err = tun_attach(tun, file);
> if (err < 0)
> return err;
> @@ -947,6 +950,9 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
>
> if (!capable(CAP_NET_ADMIN))
> return -EPERM;
> + err = security_tun_dev_create();
> + if (err < 0)
> + return err;
>
> /* Set dev type */
> if (ifr->ifr_flags & IFF_TUN) {
> @@ -989,6 +995,8 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
> tun->sk = sk;
> container_of(sk, struct tun_sock, sk)->tun = tun;
>
> + security_tun_dev_post_create(sk);
> +
> tun_net_init(dev);
>
> if (strchr(dev->name, '%')) {
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 5eff459..d8efc35 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -974,6 +974,17 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
> * Sets the connection's peersid to the secmark on skb.
> * @req_classify_flow:
> * Sets the flow's sid to the openreq sid.
> + * @tun_dev_create:
> + * Check permissions prior to creating a new TUN device.
> + * @tun_dev_post_create:
> + * This hook allows a module to update or allocate a per-socket security
> + * structure.
> + * @sk contains the newly created sock structure.
> + * @tun_dev_attach:
> + * Check permissions prior to attaching to a persistent TUN device. This
> + * hook can also be used by the module to update any security state
> + * associated with the TUN device's sock structure.
> + * @sk contains the existing sock structure.
> *
> * Security hooks for XFRM operations.
> *
> @@ -1572,6 +1583,9 @@ struct security_operations {
> void (*inet_csk_clone) (struct sock *newsk, const struct request_sock *req);
> void (*inet_conn_established) (struct sock *sk, struct sk_buff *skb);
> void (*req_classify_flow) (const struct request_sock *req, struct flowi *fl);
> + int (*tun_dev_create)(void);
> + void (*tun_dev_post_create)(struct sock *sk);
> + int (*tun_dev_attach)(struct sock *sk);
> #endif /* CONFIG_SECURITY_NETWORK */
>
> #ifdef CONFIG_SECURITY_NETWORK_XFRM
> @@ -2557,6 +2571,9 @@ void security_inet_csk_clone(struct sock *newsk,
> const struct request_sock *req);
> void security_inet_conn_established(struct sock *sk,
> struct sk_buff *skb);
> +int security_tun_dev_create(void);
> +void security_tun_dev_post_create(struct sock *sk);
> +int security_tun_dev_attach(struct sock *sk);
>
> #else /* CONFIG_SECURITY_NETWORK */
> static inline int security_unix_stream_connect(struct socket *sock,
> @@ -2707,6 +2724,20 @@ static inline void security_inet_conn_established(struct sock *sk,
> struct sk_buff *skb)
> {
> }
> +
> +static inline int security_tun_dev_create(void)
> +{
> + return 0;
> +}
> +
> +static inline void security_tun_dev_post_create(struct sock *sk)
> +{
> +}
> +
> +static inline int security_tun_dev_attach(struct sock *sk)
> +{
> + return 0;
> +}
> #endif /* CONFIG_SECURITY_NETWORK */
>
> #ifdef CONFIG_SECURITY_NETWORK_XFRM
> diff --git a/security/capability.c b/security/capability.c
> index 21b6cea..a10a44a 100644
> --- a/security/capability.c
> +++ b/security/capability.c
> @@ -710,10 +710,26 @@ static void cap_inet_conn_established(struct sock *sk, struct sk_buff *skb)
> {
> }
>
> +
> +
> static void cap_req_classify_flow(const struct request_sock *req,
> struct flowi *fl)
> {
> }
> +
> +static int cap_tun_dev_create(void)
> +{
> + return 0;
> +}
> +
> +static void cap_tun_dev_post_create(struct sock *sk)
> +{
> +}
> +
> +static int cap_tun_dev_attach(struct sock *sk)
> +{
> + return 0;
> +}
> #endif /* CONFIG_SECURITY_NETWORK */
>
> #ifdef CONFIG_SECURITY_NETWORK_XFRM
> @@ -1029,6 +1045,9 @@ void security_fixup_ops(struct security_operations *ops)
> set_to_cap_if_null(ops, inet_csk_clone);
> set_to_cap_if_null(ops, inet_conn_established);
> set_to_cap_if_null(ops, req_classify_flow);
> + set_to_cap_if_null(ops, tun_dev_create);
> + set_to_cap_if_null(ops, tun_dev_post_create);
> + set_to_cap_if_null(ops, tun_dev_attach);
> #endif /* CONFIG_SECURITY_NETWORK */
> #ifdef CONFIG_SECURITY_NETWORK_XFRM
> set_to_cap_if_null(ops, xfrm_policy_alloc_security);
> diff --git a/security/security.c b/security/security.c
> index dc7674f..dc6953c 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -1112,6 +1112,24 @@ void security_inet_conn_established(struct sock *sk,
> security_ops->inet_conn_established(sk, skb);
> }
>
> +int security_tun_dev_create(void)
> +{
> + return security_ops->tun_dev_create();
> +}
> +EXPORT_SYMBOL(security_tun_dev_create);
> +
> +void security_tun_dev_post_create(struct sock *sk)
> +{
> + return security_ops->tun_dev_post_create(sk);
> +}
> +EXPORT_SYMBOL(security_tun_dev_post_create);
> +
> +int security_tun_dev_attach(struct sock *sk)
> +{
> + return security_ops->tun_dev_attach(sk);
> +}
> +EXPORT_SYMBOL(security_tun_dev_attach);
> +
> #endif /* CONFIG_SECURITY_NETWORK */
>
> #ifdef CONFIG_SECURITY_NETWORK_XFRM
>
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^ permalink raw reply
* Re: [PATCH 1/2] mac802154: add a software MAC 802.15.4 implementation
From: Dmitry Eremin-Solenikov @ 2009-08-11 20:29 UTC (permalink / raw)
To: Paul E. McKenney
Cc: netdev-u79uwXL29TY76Z2rM5mHXA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
linux-zigbee-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f
In-Reply-To: <20090810172843.GD6791-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
On Mon, Aug 10, 2009 at 10:28:43AM -0700, Paul E. McKenney wrote:
> On Mon, Aug 10, 2009 at 06:16:39PM +0400, Dmitry Eremin-Solenikov wrote:
> > Some of available devices are just dump radios implementing IEEE 802.15.4
> > PHY layer. This commit adds a common library that acts like an intermediate
> > layer between our socket family and drivers for those dumb devices.
> >
> > Currently this is data-only part (no commands, no beacons). Control
> > interfaces will follow up shortly.
> >
> > Note this implementaion is neither certified, nor feature complete!
>
> One question below, otherwise looks plausible. (I am not entirely sure
> which lists are which...)
>
> Thanx, Paul
[skipped]
>
> > +
> > +/*
> > + * This is for hw unregistration only, as it doesn't do RCU locking
>
> So this list is different than the RCU-protected one, and readers
> always hold locks when traversing it?
>
> I am not familiar with this code, so might be missing something, but
> it looks to me like the same list that RCU readers traverse. If so,
> need list_del_rcu() and synchronize_rcu().
On the first glance, yes. On the second glance, list_del instead of
list_del_rcu should be safe as there should be now other list traversals
at the same time. I'll think about it however.
>
> > + */
> > +void ieee802154_drop_slaves(struct ieee802154_dev *hw)
> > +{
> > + struct ieee802154_priv *priv = ieee802154_to_priv(hw);
> > + struct ieee802154_sub_if_data *sdata, *next;
> > +
> > + ASSERT_RTNL();
> > +
> > + list_for_each_entry_safe(sdata, next, &priv->slaves, list) {
> > + mutex_lock(&sdata->hw->slaves_mtx);
> > + list_del(&sdata->list);
> > + mutex_unlock(&sdata->hw->slaves_mtx);
> > +
> > + dev_put(sdata->hw->netdev);
> > +
> > + unregister_netdevice(sdata->dev);
> > + }
> > +}
--
With best wishes
Dmitry
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^ permalink raw reply
* Re: [PATCH 1/2] mac802154: add a software MAC 802.15.4 implementation
From: Dmitry Eremin-Solenikov @ 2009-08-11 20:23 UTC (permalink / raw)
To: Johannes Berg
Cc: netdev-u79uwXL29TY76Z2rM5mHXA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA, Sergey Lapin
In-Reply-To: <1249914466.32614.13.camel-YfaajirXv2244ywRPIzf9A@public.gmane.org>
On Mon, Aug 10, 2009 at 04:27:46PM +0200, Johannes Berg wrote:
> On Mon, 2009-08-10 at 18:16 +0400, Dmitry Eremin-Solenikov wrote:
> > + * @tx: Handler that 802.15.4 module calls for each transmitted frame.
> > + * skb cntains the buffer starting from the IEEE 802.15.4 header.
> > + * The low-level driver should send the frame based on available
> > + * configuration.
> > + * This function should return zero or negative errno.
>
> That return value is strange.
The idea is that tx function can return info about errors during
transmit (busy channel, no ACK, etc).
>
> > +++ b/net/Makefile
> > @@ -61,6 +61,7 @@ ifneq ($(CONFIG_DCB),)
> > obj-y += dcb/
> > endif
> > obj-y += ieee802154/
> > +obj-y += mac802154/
>
> I think you should use obj-$(CONFIG_MAC802154) as there's no need to
> recurse into the dir unless that's selected.
fixed.
>
> But does it make sense to actually have this little code as a separate
> dir/module?
The submitted patch is only a part of written MAC code. And we still
aren't feature complete. Is there any sence in keeping mac80211
separate? IMHO yes. Same goes for mac802154.
> > + struct net_device *netdev; /* mwpanX device */
> > + int open_count;
> > + /* As in mac80211 slaves list is modified:
> > + * 1) under the RTNL
> > + * 2) protected by slaves_mtx;
> > + * 3) in an RCU manner
> > + *
> > + * So atomic readers can use any of this protection methods
> > + */
> > + struct list_head slaves;
>
> heh.
? C&p from mac80211 mostly :)
>
> > +static int ieee802154_master_open(struct net_device *dev)
> > +{
>
> We've had no end to trouble with the master netdev, I suggest you look
> into the current mac80211 code and see if you can get rid of it.
What troubles w/ master netdev did you have had? I do still see the
master devices in mac80211. IIUC, it's planned to replace (from
management point of view) the mdev with wiphy instance, isn't it?
> > +struct ieee802154_dev *ieee802154_alloc_device(size_t priv_size,
> > + struct ieee802154_ops *ops)
> > +{
>
> > + if (!try_module_get(ops->owner)) {
>
> That isn't necessary since the module is just calling your function. In
> fact, doing this removes the ability to rmmod any module using this
> which is bogus.
Hmm. I thought that one may be able to rmmod the module w/ ops while the
device is still hanging in the system. On the other hand, ops are
provided by the driver, so if one rmmods the driver and the device is
still there, it's a bug...
Removing now.
--
With best wishes
Dmitry
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^ permalink raw reply
* Re: Receive side performance issue with multi-10-GigE and NUMA
From: Christoph Lameter @ 2009-08-11 19:15 UTC (permalink / raw)
To: Neil Horman
Cc: Bill Fink, Andrew Gallatin, Brice Goglin,
Linux Network Developers, Yinghai Lu
In-Reply-To: <20090811110254.GA26516@hmsreliant.think-freely.org>
On Tue, 11 Aug 2009, Neil Horman wrote:
> Well, its possible that there is a kernel bug, but those tables that you're
> reading are parsed IIRC directly from the systems SRAT table in acpi space. I'm
> not sure of a way to read those directly from user space, but IIRC if you turn
> on apic debugging they will get dumped out. It sounds as though perhaps your
> SRAT table is incorrectly reporting the location of your devices. You may also
> want to look at dumping out your smbios via dmidecode to see where that places
> all your 10G nic cards.
Very likely. Talk to the manufacturer of the machine and make sure that
the ACPI information is correct. NUMA is new to many vendors because of
the recent introduction of newer processor architectures that support NUMA
for the first time in small smp machines.
^ permalink raw reply
* pull request: wireless-2.6 2009-08-11
From: John W. Linville @ 2009-08-11 18:36 UTC (permalink / raw)
To: davem; +Cc: linux-wireless, netdev, linux-kernel
Dave,
Here are a couple more minor fixes intended for 2.6.31. Hopefully we
are winding-down!
Please let me know if there are problems!
John
---
Individual patches are available here:
http://www.kernel.org/pub/linux/kernel/people/linville/wireless-2.6/
---
The following changes since commit 973507cb8610d4c84f090d5f1f0ca54fa0559d27:
roel kluin (1):
mlx4_en: Fix read buffer overflow in mlx4_en_complete_rx_desc()
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6.git master
Christian Lamparter (1):
ar9170usb: fix spurious firmware related message
Dan Carpenter (1):
ar9170: fix read & write outside array bounds
drivers/net/wireless/ath/ar9170/main.c | 5 +++--
drivers/net/wireless/ath/ar9170/usb.c | 6 +++++-
2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/ath/ar9170/main.c b/drivers/net/wireless/ath/ar9170/main.c
index 9d38cf6..88c3d85 100644
--- a/drivers/net/wireless/ath/ar9170/main.c
+++ b/drivers/net/wireless/ath/ar9170/main.c
@@ -1967,13 +1967,14 @@ static int ar9170_conf_tx(struct ieee80211_hw *hw, u16 queue,
int ret;
mutex_lock(&ar->mutex);
- if ((param) && !(queue > __AR9170_NUM_TXQ)) {
+ if (queue < __AR9170_NUM_TXQ) {
memcpy(&ar->edcf[ar9170_qos_hwmap[queue]],
param, sizeof(*param));
ret = ar9170_set_qos(ar);
- } else
+ } else {
ret = -EINVAL;
+ }
mutex_unlock(&ar->mutex);
return ret;
diff --git a/drivers/net/wireless/ath/ar9170/usb.c b/drivers/net/wireless/ath/ar9170/usb.c
index 754b1f8..007eb85 100644
--- a/drivers/net/wireless/ath/ar9170/usb.c
+++ b/drivers/net/wireless/ath/ar9170/usb.c
@@ -598,11 +598,15 @@ static int ar9170_usb_request_firmware(struct ar9170_usb *aru)
err = request_firmware(&aru->init_values, "ar9170-1.fw",
&aru->udev->dev);
+ if (err) {
+ dev_err(&aru->udev->dev, "file with init values not found.\n");
+ return err;
+ }
err = request_firmware(&aru->firmware, "ar9170-2.fw", &aru->udev->dev);
if (err) {
release_firmware(aru->init_values);
- dev_err(&aru->udev->dev, "file with init values not found.\n");
+ dev_err(&aru->udev->dev, "firmware file not found.\n");
return err;
}
--
John W. Linville Someday the world will need a hero, and you
linville@tuxdriver.com might be all we have. Be ready.
^ permalink raw reply related
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* Re: [PATCH] fix memory leak in virtio_net
From: Shirley Ma @ 2009-08-11 16:56 UTC (permalink / raw)
To: Avi Kivity; +Cc: kvm, linux-kernel, netdev, Rusty Russell
In-Reply-To: <4A815B9A.3060205@redhat.com>
Hello Avi,
I do see memory leak after removing virtio_net module. There is 72KB per
removal along with free already free IRQ. Maybe the memleak from
virtio_pci, seems some lock is missing when accessing the irq list?
Trying to free already-free IRQ 26
Modules linked in: virtio_net(-) sunrpc ipv6 virtio_balloon pcspkr
virtio_blk virtio_pci virtio_ring virtio [last unloaded: virtio_net]
Pid: 1641, comm: rmmod Tainted: G W 2.6.31-rc4 #11
Call Trace:
[<c102bc50>] warn_slowpath_common+0x60/0x90
[<c102bcb4>] warn_slowpath_fmt+0x24/0x27
[<c105d472>] __free_irq+0x74/0x134
[<c105d53a>] free_irq+0x8/0xf
[<e081012d>] vp_free_vectors+0x42/0x97 [virtio_pci]
[<e0810262>] vp_del_vqs+0xe0/0xe8 [virtio_pci]
[<e13de253>] virtnet_remove+0xf9/0x125 [virtio_net]
[<e0801097>] virtio_dev_remove+0xf/0x33 [virtio]
[<c116d5d4>] __device_release_driver+0x58/0x8e
[<c116d667>] driver_detach+0x5d/0x7b
[<c116cbe6>] bus_remove_driver+0x63/0x89
[<c116da58>] driver_unregister+0x4d/0x54
[<e0801304>] unregister_virtio_driver+0x8/0xa [virtio]
[<e13df865>] fini+0xd/0x12 [virtio_net]
[<c104d430>] sys_delete_module+0x180/0x1d7
[<c1085033>] ? remove_vma+0x55/0x5b
[<c105ac6d>] ? audit_syscall_entry+0x102/0x124
[<c1002aa9>] syscall_call+0x7/0xb
When loading the module, the complain is:
------------[ cut here ]------------
WARNING: at lib/list_debug.c:26 __list_add+0x27/0x5c()
Hardware name:
list_add corruption. next->prev should be prev (df88b3e0), but was
df466770. (next=dfbdb8d0).
Modules linked in: virtio_net(+) sunrpc ipv6 virtio_balloon pcspkr
virtio_blk virtio_pci virtio_ring virtio [last unloaded: virtio_net]
Pid: 1674, comm: modprobe Tainted: G W 2.6.31-rc4 #11
Call Trace:
[<c102bc50>] warn_slowpath_common+0x60/0x90
[<c102bcb4>] warn_slowpath_fmt+0x24/0x27
[<c1114dcf>] __list_add+0x27/0x5c
[<e08107d9>] vp_find_vqs+0x47d/0x53c [virtio_pci]
[<e14202b9>] ? skb_recv_done+0x0/0x36 [virtio_net]
[<e14210fc>] virtnet_probe+0x24f/0x376 [virtio_net]
[<e14202b9>] ? skb_recv_done+0x0/0x36 [virtio_net]
[<e142027f>] ? skb_xmit_done+0x0/0x3a [virtio_net]
[<e08108cd>] ? vp_set_status+0x20/0x22 [virtio_pci]
[<e080105d>] ? add_status+0x1f/0x24 [virtio]
[<e080114c>] virtio_dev_probe+0x91/0xb0 [virtio]
[<c116d7e3>] driver_probe_device+0x79/0x105
[<c116d8b2>] __driver_attach+0x43/0x5f
[<c116d24d>] bus_for_each_dev+0x3d/0x67
[<c116d6bc>] driver_attach+0x14/0x16
[<c116d86f>] ? __driver_attach+0x0/0x5f
^ permalink raw reply
* Re: [PATCH] be2net: Implementation of request_firmware interface.
From: Andy Gospodarek @ 2009-08-11 16:55 UTC (permalink / raw)
To: Ben Hutchings; +Cc: Sarveshwar Bandi, netdev, davem
In-Reply-To: <1246803604.3898.6.camel@deadeye>
On Sun, Jul 05, 2009 at 03:20:04PM +0100, Ben Hutchings wrote:
> On Sun, 2009-07-05 at 17:46 +0530, Sarveshwar Bandi wrote:
> > I understand that most drivers use request_firmware() to load volatile
> > firmware. I do see that there are other nic drivers that use this inferface to
> > flash persistent firmware.
> >
> > We have other tools for offline flashing; but there is requirement
> > to flash f/w through driver without having to use other proprietary tools.
>
> The firmware blob is proprietary and has to be distributed separately
> from the kernel. So does it really matter that you have to distribute a
> special tool as well?
>
I guess I don't share the same opinion that the binary firmware is
required to be distributed separately since it is not that way today.
If we get rid of all files in firmware/ that do not have source
included, there will not be much left.
I applaud efforts by hardware vendors and others to submit patches that
allow drivers to update their own firmware at load-time if the on-card
version isn't compatible with the driver getting ready to load. If one
does not want them updated, don't put the files in /lib/firmware.
Using a standard method (like using request_firmware) seems much more
logical than requiring users to download and compile some vendor
specific application to get new firmware. It also means that if a
vendor is willing to drop a binary blob into firmware/ it's a pretty
easy thing to do.
> (Based on requirements specified by major OEMs, I have implemented
> firmware update through the sfc driver (MDIO and MTD interfaces) but
> under the control of a separate tool.)
And there are plenty of OEMs out there that complain loudly if it's not
easy to move quickly from one on-card/in-memory firmware to another when
changing driver versions. Trust me, I hear from them.
^ permalink raw reply
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