linux/drivers/net/xen-netback/xenbus.c

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details [based] [from] [clk] [highbank] [c] you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 355 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-19 21:51:43 +08:00
// SPDX-License-Identifier: GPL-2.0-or-later
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
/*
* Xenbus code for netif backend
*
* Copyright (C) 2005 Rusty Russell <rusty@rustcorp.com.au>
* Copyright (C) 2005 XenSource Ltd
*/
#include "common.h"
#include <linux/vmalloc.h>
#include <linux/rtnetlink.h>
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
static int connect_data_rings(struct backend_info *be,
struct xenvif_queue *queue);
static void connect(struct backend_info *be);
static int read_xenbus_vif_flags(struct backend_info *be);
static int backend_create_xenvif(struct backend_info *be);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
static void unregister_hotplug_status_watch(struct backend_info *be);
static void xen_unregister_watchers(struct xenvif *vif);
static void set_backend_state(struct backend_info *be,
enum xenbus_state state);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
#ifdef CONFIG_DEBUG_FS
struct dentry *xen_netback_dbg_root = NULL;
static int xenvif_read_io_ring(struct seq_file *m, void *v)
{
struct xenvif_queue *queue = m->private;
struct xen_netif_tx_back_ring *tx_ring = &queue->tx;
struct xen_netif_rx_back_ring *rx_ring = &queue->rx;
xen-netback: fix unlimited guest Rx internal queue and carrier flapping Netback needs to discard old to-guest skb's (guest Rx queue drain) and it needs detect guest Rx stalls (to disable the carrier so packets are discarded earlier), but the current implementation is very broken. 1. The check in hard_start_xmit of the slot availability did not consider the number of packets that were already in the guest Rx queue. This could allow the queue to grow without bound. The guest stops consuming packets and the ring was allowed to fill leaving S slot free. Netback queues a packet requiring more than S slots (ensuring that the ring stays with S slots free). Netback queue indefinately packets provided that then require S or fewer slots. 2. The Rx stall detection is not triggered in this case since the (host) Tx queue is not stopped. 3. If the Tx queue is stopped and a guest Rx interrupt occurs, netback will consider this an Rx purge event which may result in it taking the carrier down unnecessarily. It also considers a queue with only 1 slot free as unstalled (even though the next packet might not fit in this). The internal guest Rx queue is limited by a byte length (to 512 Kib, enough for half the ring). The (host) Tx queue is stopped and started based on this limit. This sets an upper bound on the amount of memory used by packets on the internal queue. This allows the estimatation of the number of slots for an skb to be removed (it wasn't a very good estimate anyway). Instead, the guest Rx thread just waits for enough free slots for a maximum sized packet. skbs queued on the internal queue have an 'expires' time (set to the current time plus the drain timeout). The guest Rx thread will detect when the skb at the head of the queue has expired and discard expired skbs. This sets a clear upper bound on the length of time an skb can be queued for. For a guest being destroyed the maximum time needed to wait for all the packets it sent to be dropped is still the drain timeout (10 s) since it will not be sending new packets. Rx stall detection is reintroduced in a later commit. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-22 21:08:54 +08:00
struct netdev_queue *dev_queue;
if (tx_ring->sring) {
struct xen_netif_tx_sring *sring = tx_ring->sring;
seq_printf(m, "Queue %d\nTX: nr_ents %u\n", queue->id,
tx_ring->nr_ents);
seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n",
sring->req_prod,
sring->req_prod - sring->rsp_prod,
tx_ring->req_cons,
tx_ring->req_cons - sring->rsp_prod,
sring->req_event,
sring->req_event - sring->rsp_prod);
seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n",
sring->rsp_prod,
tx_ring->rsp_prod_pvt,
tx_ring->rsp_prod_pvt - sring->rsp_prod,
sring->rsp_event,
sring->rsp_event - sring->rsp_prod);
seq_printf(m, "pending prod %u pending cons %u nr_pending_reqs %u\n",
queue->pending_prod,
queue->pending_cons,
nr_pending_reqs(queue));
seq_printf(m, "dealloc prod %u dealloc cons %u dealloc_queue %u\n\n",
queue->dealloc_prod,
queue->dealloc_cons,
queue->dealloc_prod - queue->dealloc_cons);
}
if (rx_ring->sring) {
struct xen_netif_rx_sring *sring = rx_ring->sring;
seq_printf(m, "RX: nr_ents %u\n", rx_ring->nr_ents);
seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n",
sring->req_prod,
sring->req_prod - sring->rsp_prod,
rx_ring->req_cons,
rx_ring->req_cons - sring->rsp_prod,
sring->req_event,
sring->req_event - sring->rsp_prod);
seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n\n",
sring->rsp_prod,
rx_ring->rsp_prod_pvt,
rx_ring->rsp_prod_pvt - sring->rsp_prod,
sring->rsp_event,
sring->rsp_event - sring->rsp_prod);
}
seq_printf(m, "NAPI state: %lx NAPI weight: %d TX queue len %u\n"
"Credit timer_pending: %d, credit: %lu, usec: %lu\n"
"remaining: %lu, expires: %lu, now: %lu\n",
queue->napi.state, queue->napi.weight,
skb_queue_len(&queue->tx_queue),
timer_pending(&queue->credit_timeout),
queue->credit_bytes,
queue->credit_usec,
queue->remaining_credit,
queue->credit_timeout.expires,
jiffies);
xen-netback: fix unlimited guest Rx internal queue and carrier flapping Netback needs to discard old to-guest skb's (guest Rx queue drain) and it needs detect guest Rx stalls (to disable the carrier so packets are discarded earlier), but the current implementation is very broken. 1. The check in hard_start_xmit of the slot availability did not consider the number of packets that were already in the guest Rx queue. This could allow the queue to grow without bound. The guest stops consuming packets and the ring was allowed to fill leaving S slot free. Netback queues a packet requiring more than S slots (ensuring that the ring stays with S slots free). Netback queue indefinately packets provided that then require S or fewer slots. 2. The Rx stall detection is not triggered in this case since the (host) Tx queue is not stopped. 3. If the Tx queue is stopped and a guest Rx interrupt occurs, netback will consider this an Rx purge event which may result in it taking the carrier down unnecessarily. It also considers a queue with only 1 slot free as unstalled (even though the next packet might not fit in this). The internal guest Rx queue is limited by a byte length (to 512 Kib, enough for half the ring). The (host) Tx queue is stopped and started based on this limit. This sets an upper bound on the amount of memory used by packets on the internal queue. This allows the estimatation of the number of slots for an skb to be removed (it wasn't a very good estimate anyway). Instead, the guest Rx thread just waits for enough free slots for a maximum sized packet. skbs queued on the internal queue have an 'expires' time (set to the current time plus the drain timeout). The guest Rx thread will detect when the skb at the head of the queue has expired and discard expired skbs. This sets a clear upper bound on the length of time an skb can be queued for. For a guest being destroyed the maximum time needed to wait for all the packets it sent to be dropped is still the drain timeout (10 s) since it will not be sending new packets. Rx stall detection is reintroduced in a later commit. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-22 21:08:54 +08:00
dev_queue = netdev_get_tx_queue(queue->vif->dev, queue->id);
seq_printf(m, "\nRx internal queue: len %u max %u pkts %u %s\n",
queue->rx_queue_len, queue->rx_queue_max,
skb_queue_len(&queue->rx_queue),
netif_tx_queue_stopped(dev_queue) ? "stopped" : "running");
return 0;
}
#define XENVIF_KICK_STR "kick"
#define BUFFER_SIZE 32
static ssize_t
xenvif_write_io_ring(struct file *filp, const char __user *buf, size_t count,
loff_t *ppos)
{
struct xenvif_queue *queue =
((struct seq_file *)filp->private_data)->private;
int len;
char write[BUFFER_SIZE];
/* don't allow partial writes and check the length */
if (*ppos != 0)
return 0;
if (count >= sizeof(write))
return -ENOSPC;
len = simple_write_to_buffer(write,
sizeof(write) - 1,
ppos,
buf,
count);
if (len < 0)
return len;
write[len] = '\0';
if (!strncmp(write, XENVIF_KICK_STR, sizeof(XENVIF_KICK_STR) - 1))
xenvif_interrupt(0, (void *)queue);
else {
pr_warn("Unknown command to io_ring_q%d. Available: kick\n",
queue->id);
count = -EINVAL;
}
return count;
}
static int xenvif_io_ring_open(struct inode *inode, struct file *filp)
{
int ret;
void *queue = NULL;
if (inode->i_private)
queue = inode->i_private;
ret = single_open(filp, xenvif_read_io_ring, queue);
filp->f_mode |= FMODE_PWRITE;
return ret;
}
static const struct file_operations xenvif_dbg_io_ring_ops_fops = {
.owner = THIS_MODULE,
.open = xenvif_io_ring_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
.write = xenvif_write_io_ring,
};
static int xenvif_ctrl_show(struct seq_file *m, void *v)
{
struct xenvif *vif = m->private;
xenvif_dump_hash_info(vif, m);
return 0;
}
DEFINE_SHOW_ATTRIBUTE(xenvif_ctrl);
static void xenvif_debugfs_addif(struct xenvif *vif)
{
int i;
vif->xenvif_dbg_root = debugfs_create_dir(vif->dev->name,
xen_netback_dbg_root);
for (i = 0; i < vif->num_queues; ++i) {
char filename[sizeof("io_ring_q") + 4];
snprintf(filename, sizeof(filename), "io_ring_q%d", i);
debugfs_create_file(filename, 0600, vif->xenvif_dbg_root,
&vif->queues[i],
&xenvif_dbg_io_ring_ops_fops);
}
if (vif->ctrl_irq)
debugfs_create_file("ctrl", 0400, vif->xenvif_dbg_root, vif,
&xenvif_ctrl_fops);
}
static void xenvif_debugfs_delif(struct xenvif *vif)
{
debugfs_remove_recursive(vif->xenvif_dbg_root);
vif->xenvif_dbg_root = NULL;
}
#endif /* CONFIG_DEBUG_FS */
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
/*
* Handle the creation of the hotplug script environment. We add the script
* and vif variables to the environment, for the benefit of the vif-* hotplug
* scripts.
*/
static int netback_uevent(struct xenbus_device *xdev,
struct kobj_uevent_env *env)
{
struct backend_info *be = dev_get_drvdata(&xdev->dev);
2015-06-01 18:30:24 +08:00
if (!be)
return 0;
if (add_uevent_var(env, "script=%s", be->hotplug_script))
return -ENOMEM;
if (!be->vif)
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
return 0;
return add_uevent_var(env, "vif=%s", be->vif->dev->name);
}
static int backend_create_xenvif(struct backend_info *be)
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
{
int err;
long handle;
struct xenbus_device *dev = be->dev;
struct xenvif *vif;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
if (be->vif != NULL)
return 0;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle);
if (err != 1) {
xenbus_dev_fatal(dev, err, "reading handle");
return (err < 0) ? err : -EINVAL;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle);
if (IS_ERR(vif)) {
err = PTR_ERR(vif);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
xenbus_dev_fatal(dev, err, "creating interface");
return err;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
be->vif = vif;
vif->be = be;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE);
return 0;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
static void backend_disconnect(struct backend_info *be)
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
{
struct xenvif *vif = be->vif;
if (vif) {
unsigned int num_queues = vif->num_queues;
unsigned int queue_index;
xen_unregister_watchers(vif);
#ifdef CONFIG_DEBUG_FS
xenvif_debugfs_delif(vif);
#endif /* CONFIG_DEBUG_FS */
xenvif_disconnect_data(vif);
/* At this point some of the handlers may still be active
* so we need to have additional synchronization here.
*/
vif->num_queues = 0;
synchronize_net();
for (queue_index = 0; queue_index < num_queues; ++queue_index)
xenvif_deinit_queue(&vif->queues[queue_index]);
vfree(vif->queues);
vif->queues = NULL;
xen-netback: don't vfree() queues under spinlock This leads to a BUG of the following form: [ 174.512861] switch: port 2(vif3.0) entered disabled state [ 174.522735] BUG: sleeping function called from invalid context at /home/build/linux-linus/mm/vmalloc.c:1441 [ 174.523451] in_atomic(): 1, irqs_disabled(): 0, pid: 28, name: xenwatch [ 174.524131] CPU: 1 PID: 28 Comm: xenwatch Tainted: G W 4.10.0upstream-11073-g4977ab6-dirty #1 [ 174.524819] Hardware name: MSI MS-7680/H61M-P23 (MS-7680), BIOS V17.0 03/14/2011 [ 174.525517] Call Trace: [ 174.526217] show_stack+0x23/0x60 [ 174.526899] dump_stack+0x5b/0x88 [ 174.527562] ___might_sleep+0xde/0x130 [ 174.528208] __might_sleep+0x35/0xa0 [ 174.528840] ? _raw_spin_unlock_irqrestore+0x13/0x20 [ 174.529463] ? __wake_up+0x40/0x50 [ 174.530089] remove_vm_area+0x20/0x90 [ 174.530724] __vunmap+0x1d/0xc0 [ 174.531346] ? delete_object_full+0x13/0x20 [ 174.531973] vfree+0x40/0x80 [ 174.532594] set_backend_state+0x18a/0xa90 [ 174.533221] ? dwc_scan_descriptors+0x24d/0x430 [ 174.533850] ? kfree+0x5b/0xc0 [ 174.534476] ? xenbus_read+0x3d/0x50 [ 174.535101] ? xenbus_read+0x3d/0x50 [ 174.535718] ? xenbus_gather+0x31/0x90 [ 174.536332] ? ___might_sleep+0xf6/0x130 [ 174.536945] frontend_changed+0x6b/0xd0 [ 174.537565] xenbus_otherend_changed+0x7d/0x80 [ 174.538185] frontend_changed+0x12/0x20 [ 174.538803] xenwatch_thread+0x74/0x110 [ 174.539417] ? woken_wake_function+0x20/0x20 [ 174.540049] kthread+0xe5/0x120 [ 174.540663] ? xenbus_printf+0x50/0x50 [ 174.541278] ? __kthread_init_worker+0x40/0x40 [ 174.541898] ret_from_fork+0x21/0x2c [ 174.548635] switch: port 2(vif3.0) entered disabled state This patch defers the vfree() until after the spinlock is released. Reported-by: Juergen Gross <jgross@suse.com> Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-02 20:54:26 +08:00
xenvif_disconnect_ctrl(vif);
}
}
static void backend_connect(struct backend_info *be)
{
if (be->vif)
connect(be);
}
static inline void backend_switch_state(struct backend_info *be,
enum xenbus_state state)
{
struct xenbus_device *dev = be->dev;
pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state));
be->state = state;
/* If we are waiting for a hotplug script then defer the
* actual xenbus state change.
*/
if (!be->have_hotplug_status_watch)
xenbus_switch_state(dev, state);
}
/* Handle backend state transitions:
*
* The backend state starts in Initialising and the following transitions are
* allowed.
*
* Initialising -> InitWait -> Connected
* \
* \ ^ \ |
* \ | \ |
* \ | \ |
* \ | \ |
* \ | \ |
* \ | \ |
* V | V V
*
* Closed <-> Closing
*
* The state argument specifies the eventual state of the backend and the
* function transitions to that state via the shortest path.
*/
static void set_backend_state(struct backend_info *be,
enum xenbus_state state)
{
while (be->state != state) {
switch (be->state) {
case XenbusStateInitialising:
switch (state) {
case XenbusStateInitWait:
case XenbusStateConnected:
case XenbusStateClosing:
backend_switch_state(be, XenbusStateInitWait);
break;
case XenbusStateClosed:
backend_switch_state(be, XenbusStateClosed);
break;
default:
BUG();
}
break;
case XenbusStateClosed:
switch (state) {
case XenbusStateInitWait:
case XenbusStateConnected:
backend_switch_state(be, XenbusStateInitWait);
break;
case XenbusStateClosing:
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateInitWait:
switch (state) {
case XenbusStateConnected:
backend_connect(be);
backend_switch_state(be, XenbusStateConnected);
break;
case XenbusStateClosing:
case XenbusStateClosed:
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateConnected:
switch (state) {
case XenbusStateInitWait:
case XenbusStateClosing:
case XenbusStateClosed:
backend_disconnect(be);
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateClosing:
switch (state) {
case XenbusStateInitWait:
case XenbusStateConnected:
case XenbusStateClosed:
backend_switch_state(be, XenbusStateClosed);
break;
default:
BUG();
}
break;
default:
BUG();
}
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
}
static void read_xenbus_frontend_xdp(struct backend_info *be,
struct xenbus_device *dev)
{
struct xenvif *vif = be->vif;
u16 headroom;
int err;
err = xenbus_scanf(XBT_NIL, dev->otherend,
"xdp-headroom", "%hu", &headroom);
if (err != 1) {
vif->xdp_headroom = 0;
return;
}
if (headroom > XEN_NETIF_MAX_XDP_HEADROOM)
headroom = XEN_NETIF_MAX_XDP_HEADROOM;
vif->xdp_headroom = headroom;
}
/*
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
* Callback received when the frontend's state changes.
*/
static void frontend_changed(struct xenbus_device *dev,
enum xenbus_state frontend_state)
{
struct backend_info *be = dev_get_drvdata(&dev->dev);
pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state));
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
be->frontend_state = frontend_state;
switch (frontend_state) {
case XenbusStateInitialising:
set_backend_state(be, XenbusStateInitWait);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
break;
case XenbusStateInitialised:
break;
case XenbusStateConnected:
set_backend_state(be, XenbusStateConnected);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
break;
case XenbusStateReconfiguring:
read_xenbus_frontend_xdp(be, dev);
xenbus_switch_state(dev, XenbusStateReconfigured);
break;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
case XenbusStateClosing:
set_backend_state(be, XenbusStateClosing);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
break;
case XenbusStateClosed:
set_backend_state(be, XenbusStateClosed);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
if (xenbus_dev_is_online(dev))
break;
fallthrough; /* if not online */
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
case XenbusStateUnknown:
set_backend_state(be, XenbusStateClosed);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
device_unregister(&dev->dev);
break;
default:
xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
frontend_state);
break;
}
}
static void xen_net_read_rate(struct xenbus_device *dev,
unsigned long *bytes, unsigned long *usec)
{
char *s, *e;
unsigned long b, u;
char *ratestr;
/* Default to unlimited bandwidth. */
*bytes = ~0UL;
*usec = 0;
ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
if (IS_ERR(ratestr))
return;
s = ratestr;
b = simple_strtoul(s, &e, 10);
if ((s == e) || (*e != ','))
goto fail;
s = e + 1;
u = simple_strtoul(s, &e, 10);
if ((s == e) || (*e != '\0'))
goto fail;
*bytes = b;
*usec = u;
kfree(ratestr);
return;
fail:
pr_warn("Failed to parse network rate limit. Traffic unlimited.\n");
kfree(ratestr);
}
static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[])
{
char *s, *e, *macstr;
int i;
macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
if (IS_ERR(macstr))
return PTR_ERR(macstr);
for (i = 0; i < ETH_ALEN; i++) {
mac[i] = simple_strtoul(s, &e, 16);
if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) {
kfree(macstr);
return -ENOENT;
}
s = e+1;
}
kfree(macstr);
return 0;
}
static void xen_net_rate_changed(struct xenbus_watch *watch,
const char *path, const char *token)
{
struct xenvif *vif = container_of(watch, struct xenvif, credit_watch);
struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
unsigned long credit_bytes;
unsigned long credit_usec;
unsigned int queue_index;
xen_net_read_rate(dev, &credit_bytes, &credit_usec);
for (queue_index = 0; queue_index < vif->num_queues; queue_index++) {
struct xenvif_queue *queue = &vif->queues[queue_index];
queue->credit_bytes = credit_bytes;
queue->credit_usec = credit_usec;
if (!mod_timer_pending(&queue->credit_timeout, jiffies) &&
queue->remaining_credit > queue->credit_bytes) {
queue->remaining_credit = queue->credit_bytes;
}
}
}
static int xen_register_credit_watch(struct xenbus_device *dev,
struct xenvif *vif)
{
int err = 0;
char *node;
unsigned maxlen = strlen(dev->nodename) + sizeof("/rate");
if (vif->credit_watch.node)
return -EADDRINUSE;
node = kmalloc(maxlen, GFP_KERNEL);
if (!node)
return -ENOMEM;
snprintf(node, maxlen, "%s/rate", dev->nodename);
vif->credit_watch.node = node;
vif->credit_watch.will_handle = NULL;
vif->credit_watch.callback = xen_net_rate_changed;
err = register_xenbus_watch(&vif->credit_watch);
if (err) {
pr_err("Failed to set watcher %s\n", vif->credit_watch.node);
kfree(node);
vif->credit_watch.node = NULL;
vif->credit_watch.will_handle = NULL;
vif->credit_watch.callback = NULL;
}
return err;
}
static void xen_unregister_credit_watch(struct xenvif *vif)
{
if (vif->credit_watch.node) {
unregister_xenbus_watch(&vif->credit_watch);
kfree(vif->credit_watch.node);
vif->credit_watch.node = NULL;
}
}
static void xen_mcast_ctrl_changed(struct xenbus_watch *watch,
const char *path, const char *token)
{
struct xenvif *vif = container_of(watch, struct xenvif,
mcast_ctrl_watch);
struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
vif->multicast_control = !!xenbus_read_unsigned(dev->otherend,
"request-multicast-control", 0);
}
static int xen_register_mcast_ctrl_watch(struct xenbus_device *dev,
struct xenvif *vif)
{
int err = 0;
char *node;
unsigned maxlen = strlen(dev->otherend) +
sizeof("/request-multicast-control");
if (vif->mcast_ctrl_watch.node) {
pr_err_ratelimited("Watch is already registered\n");
return -EADDRINUSE;
}
node = kmalloc(maxlen, GFP_KERNEL);
if (!node) {
pr_err("Failed to allocate memory for watch\n");
return -ENOMEM;
}
snprintf(node, maxlen, "%s/request-multicast-control",
dev->otherend);
vif->mcast_ctrl_watch.node = node;
vif->mcast_ctrl_watch.will_handle = NULL;
vif->mcast_ctrl_watch.callback = xen_mcast_ctrl_changed;
err = register_xenbus_watch(&vif->mcast_ctrl_watch);
if (err) {
pr_err("Failed to set watcher %s\n",
vif->mcast_ctrl_watch.node);
kfree(node);
vif->mcast_ctrl_watch.node = NULL;
vif->mcast_ctrl_watch.will_handle = NULL;
vif->mcast_ctrl_watch.callback = NULL;
}
return err;
}
static void xen_unregister_mcast_ctrl_watch(struct xenvif *vif)
{
if (vif->mcast_ctrl_watch.node) {
unregister_xenbus_watch(&vif->mcast_ctrl_watch);
kfree(vif->mcast_ctrl_watch.node);
vif->mcast_ctrl_watch.node = NULL;
}
}
static void xen_register_watchers(struct xenbus_device *dev,
struct xenvif *vif)
{
xen_register_credit_watch(dev, vif);
xen_register_mcast_ctrl_watch(dev, vif);
}
static void xen_unregister_watchers(struct xenvif *vif)
{
xen_unregister_mcast_ctrl_watch(vif);
xen_unregister_credit_watch(vif);
}
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
static void unregister_hotplug_status_watch(struct backend_info *be)
{
if (be->have_hotplug_status_watch) {
unregister_xenbus_watch(&be->hotplug_status_watch);
kfree(be->hotplug_status_watch.node);
}
be->have_hotplug_status_watch = 0;
}
static void hotplug_status_changed(struct xenbus_watch *watch,
const char *path,
const char *token)
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
{
struct backend_info *be = container_of(watch,
struct backend_info,
hotplug_status_watch);
char *str;
unsigned int len;
str = xenbus_read(XBT_NIL, be->dev->nodename, "hotplug-status", &len);
if (IS_ERR(str))
return;
if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) {
/* Complete any pending state change */
xenbus_switch_state(be->dev, be->state);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
/* Not interested in this watch anymore. */
unregister_hotplug_status_watch(be);
xenbus_rm(XBT_NIL, be->dev->nodename, "hotplug-status");
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
kfree(str);
}
static int connect_ctrl_ring(struct backend_info *be)
{
struct xenbus_device *dev = be->dev;
struct xenvif *vif = be->vif;
unsigned int val;
grant_ref_t ring_ref;
unsigned int evtchn;
int err;
err = xenbus_scanf(XBT_NIL, dev->otherend,
"ctrl-ring-ref", "%u", &val);
if (err < 0)
goto done; /* The frontend does not have a control ring */
ring_ref = val;
err = xenbus_scanf(XBT_NIL, dev->otherend,
"event-channel-ctrl", "%u", &val);
if (err < 0) {
xenbus_dev_fatal(dev, err,
"reading %s/event-channel-ctrl",
dev->otherend);
goto fail;
}
evtchn = val;
err = xenvif_connect_ctrl(vif, ring_ref, evtchn);
if (err) {
xenbus_dev_fatal(dev, err,
"mapping shared-frame %u port %u",
ring_ref, evtchn);
goto fail;
}
done:
return 0;
fail:
return err;
}
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
static void connect(struct backend_info *be)
{
int err;
struct xenbus_device *dev = be->dev;
unsigned long credit_bytes, credit_usec;
unsigned int queue_index;
unsigned int requested_num_queues;
struct xenvif_queue *queue;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
/* Check whether the frontend requested multiple queues
* and read the number requested.
*/
requested_num_queues = xenbus_read_unsigned(dev->otherend,
"multi-queue-num-queues", 1);
if (requested_num_queues > xenvif_max_queues) {
/* buggy or malicious guest */
xenbus_dev_fatal(dev, -EINVAL,
"guest requested %u queues, exceeding the maximum of %u.",
requested_num_queues, xenvif_max_queues);
return;
}
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
err = xen_net_read_mac(dev, be->vif->fe_dev_addr);
if (err) {
xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
return;
}
xen_net_read_rate(dev, &credit_bytes, &credit_usec);
xen_unregister_watchers(be->vif);
xen_register_watchers(dev, be->vif);
read_xenbus_vif_flags(be);
err = connect_ctrl_ring(be);
if (err) {
xenbus_dev_fatal(dev, err, "connecting control ring");
return;
}
/* Use the number of queues requested by the frontend */
treewide: Use array_size() in vzalloc() The vzalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vzalloc(a * b) with: vzalloc(array_size(a, b)) as well as handling cases of: vzalloc(a * b * c) with: vzalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vzalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(char) * COUNT + COUNT , ...) | vzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vzalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vzalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vzalloc(C1 * C2 * C3, ...) | vzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vzalloc(C1 * C2, ...) | vzalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-13 05:27:37 +08:00
be->vif->queues = vzalloc(array_size(requested_num_queues,
sizeof(struct xenvif_queue)));
if (!be->vif->queues) {
xenbus_dev_fatal(dev, -ENOMEM,
"allocating queues");
return;
}
be->vif->num_queues = requested_num_queues;
be->vif->stalled_queues = requested_num_queues;
for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) {
queue = &be->vif->queues[queue_index];
queue->vif = be->vif;
queue->id = queue_index;
snprintf(queue->name, sizeof(queue->name), "%s-q%u",
be->vif->dev->name, queue->id);
err = xenvif_init_queue(queue);
if (err) {
/* xenvif_init_queue() cleans up after itself on
* failure, but we need to clean up any previously
* initialised queues. Set num_queues to i so that
* earlier queues can be destroyed using the regular
* disconnect logic.
*/
be->vif->num_queues = queue_index;
goto err;
}
queue->credit_bytes = credit_bytes;
queue->remaining_credit = credit_bytes;
queue->credit_usec = credit_usec;
err = connect_data_rings(be, queue);
if (err) {
/* connect_data_rings() cleans up after itself on
* failure, but we need to clean up after
* xenvif_init_queue() here, and also clean up any
* previously initialised queues.
*/
xenvif_deinit_queue(queue);
be->vif->num_queues = queue_index;
goto err;
}
}
#ifdef CONFIG_DEBUG_FS
xenvif_debugfs_addif(be->vif);
#endif /* CONFIG_DEBUG_FS */
/* Initialisation completed, tell core driver the number of
* active queues.
*/
rtnl_lock();
netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues);
netif_set_real_num_rx_queues(be->vif->dev, requested_num_queues);
rtnl_unlock();
xenvif_carrier_on(be->vif);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
unregister_hotplug_status_watch(be);
err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, NULL,
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
hotplug_status_changed,
"%s/%s", dev->nodename, "hotplug-status");
if (!err)
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
be->have_hotplug_status_watch = 1;
netif_tx_wake_all_queues(be->vif->dev);
return;
err:
if (be->vif->num_queues > 0)
xenvif_disconnect_data(be->vif); /* Clean up existing queues */
for (queue_index = 0; queue_index < be->vif->num_queues; ++queue_index)
xenvif_deinit_queue(&be->vif->queues[queue_index]);
vfree(be->vif->queues);
be->vif->queues = NULL;
be->vif->num_queues = 0;
xenvif_disconnect_ctrl(be->vif);
return;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
static int connect_data_rings(struct backend_info *be,
struct xenvif_queue *queue)
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
{
struct xenbus_device *dev = be->dev;
unsigned int num_queues = queue->vif->num_queues;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
unsigned long tx_ring_ref, rx_ring_ref;
unsigned int tx_evtchn, rx_evtchn;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
int err;
char *xspath;
size_t xspathsize;
const size_t xenstore_path_ext_size = 11; /* sufficient for "/queue-NNN" */
/* If the frontend requested 1 queue, or we have fallen back
* to single queue due to lack of frontend support for multi-
* queue, expect the remaining XenStore keys in the toplevel
* directory. Otherwise, expect them in a subdirectory called
* queue-N.
*/
if (num_queues == 1) {
xspath = kzalloc(strlen(dev->otherend) + 1, GFP_KERNEL);
if (!xspath) {
xenbus_dev_fatal(dev, -ENOMEM,
"reading ring references");
return -ENOMEM;
}
strcpy(xspath, dev->otherend);
} else {
xspathsize = strlen(dev->otherend) + xenstore_path_ext_size;
xspath = kzalloc(xspathsize, GFP_KERNEL);
if (!xspath) {
xenbus_dev_fatal(dev, -ENOMEM,
"reading ring references");
return -ENOMEM;
}
snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend,
queue->id);
}
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
err = xenbus_gather(XBT_NIL, xspath,
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
"tx-ring-ref", "%lu", &tx_ring_ref,
"rx-ring-ref", "%lu", &rx_ring_ref, NULL);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
if (err) {
xenbus_dev_fatal(dev, err,
"reading %s/ring-ref",
xspath);
goto err;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
/* Try split event channels first, then single event channel. */
err = xenbus_gather(XBT_NIL, xspath,
"event-channel-tx", "%u", &tx_evtchn,
"event-channel-rx", "%u", &rx_evtchn, NULL);
if (err < 0) {
err = xenbus_scanf(XBT_NIL, xspath,
"event-channel", "%u", &tx_evtchn);
if (err < 0) {
xenbus_dev_fatal(dev, err,
"reading %s/event-channel(-tx/rx)",
xspath);
goto err;
}
rx_evtchn = tx_evtchn;
}
/* Map the shared frame, irq etc. */
err = xenvif_connect_data(queue, tx_ring_ref, rx_ring_ref,
tx_evtchn, rx_evtchn);
if (err) {
xenbus_dev_fatal(dev, err,
"mapping shared-frames %lu/%lu port tx %u rx %u",
tx_ring_ref, rx_ring_ref,
tx_evtchn, rx_evtchn);
goto err;
}
err = 0;
err: /* Regular return falls through with err == 0 */
kfree(xspath);
return err;
}
static int read_xenbus_vif_flags(struct backend_info *be)
{
struct xenvif *vif = be->vif;
struct xenbus_device *dev = be->dev;
unsigned int rx_copy;
int err;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u",
&rx_copy);
if (err == -ENOENT) {
err = 0;
rx_copy = 0;
}
if (err < 0) {
xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy",
dev->otherend);
return err;
}
if (!rx_copy)
return -EOPNOTSUPP;
if (!xenbus_read_unsigned(dev->otherend, "feature-rx-notify", 0)) {
/* - Reduce drain timeout to poll more frequently for
* Rx requests.
* - Disable Rx stall detection.
*/
be->vif->drain_timeout = msecs_to_jiffies(30);
be->vif->stall_timeout = 0;
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
vif->can_sg = !!xenbus_read_unsigned(dev->otherend, "feature-sg", 0);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
vif->gso_mask = 0;
if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv4", 0))
vif->gso_mask |= GSO_BIT(TCPV4);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv6", 0))
vif->gso_mask |= GSO_BIT(TCPV6);
vif->ip_csum = !xenbus_read_unsigned(dev->otherend,
"feature-no-csum-offload", 0);
vif->ipv6_csum = !!xenbus_read_unsigned(dev->otherend,
"feature-ipv6-csum-offload", 0);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
read_xenbus_frontend_xdp(be, dev);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
return 0;
}
static int netback_remove(struct xenbus_device *dev)
{
struct backend_info *be = dev_get_drvdata(&dev->dev);
unregister_hotplug_status_watch(be);
if (be->vif) {
kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
backend_disconnect(be);
xenvif_free(be->vif);
be->vif = NULL;
}
kfree(be->hotplug_script);
kfree(be);
dev_set_drvdata(&dev->dev, NULL);
return 0;
}
/*
* Entry point to this code when a new device is created. Allocate the basic
* structures and switch to InitWait.
*/
static int netback_probe(struct xenbus_device *dev,
const struct xenbus_device_id *id)
{
const char *message;
struct xenbus_transaction xbt;
int err;
int sg;
const char *script;
struct backend_info *be = kzalloc(sizeof(*be), GFP_KERNEL);
if (!be) {
xenbus_dev_fatal(dev, -ENOMEM,
"allocating backend structure");
return -ENOMEM;
}
be->dev = dev;
dev_set_drvdata(&dev->dev, be);
sg = 1;
do {
err = xenbus_transaction_start(&xbt);
if (err) {
xenbus_dev_fatal(dev, err, "starting transaction");
goto fail;
}
err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg);
if (err) {
message = "writing feature-sg";
goto abort_transaction;
}
err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4",
"%d", sg);
if (err) {
message = "writing feature-gso-tcpv4";
goto abort_transaction;
}
err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6",
"%d", sg);
if (err) {
message = "writing feature-gso-tcpv6";
goto abort_transaction;
}
/* We support partial checksum setup for IPv6 packets */
err = xenbus_printf(xbt, dev->nodename,
"feature-ipv6-csum-offload",
"%d", 1);
if (err) {
message = "writing feature-ipv6-csum-offload";
goto abort_transaction;
}
/* We support rx-copy path. */
err = xenbus_printf(xbt, dev->nodename,
"feature-rx-copy", "%d", 1);
if (err) {
message = "writing feature-rx-copy";
goto abort_transaction;
}
/* we can adjust a headroom for netfront XDP processing */
err = xenbus_printf(xbt, dev->nodename,
"feature-xdp-headroom", "%d",
provides_xdp_headroom);
if (err) {
message = "writing feature-xdp-headroom";
goto abort_transaction;
}
/* We don't support rx-flip path (except old guests who
* don't grok this feature flag).
*/
err = xenbus_printf(xbt, dev->nodename,
"feature-rx-flip", "%d", 0);
if (err) {
message = "writing feature-rx-flip";
goto abort_transaction;
}
/* We support dynamic multicast-control. */
err = xenbus_printf(xbt, dev->nodename,
"feature-multicast-control", "%d", 1);
if (err) {
message = "writing feature-multicast-control";
goto abort_transaction;
}
err = xenbus_printf(xbt, dev->nodename,
"feature-dynamic-multicast-control",
"%d", 1);
if (err) {
message = "writing feature-dynamic-multicast-control";
goto abort_transaction;
}
err = xenbus_transaction_end(xbt, 0);
} while (err == -EAGAIN);
if (err) {
xenbus_dev_fatal(dev, err, "completing transaction");
goto fail;
}
/* Split event channels support, this is optional so it is not
* put inside the above loop.
*/
err = xenbus_printf(XBT_NIL, dev->nodename,
"feature-split-event-channels",
"%u", separate_tx_rx_irq);
if (err)
pr_debug("Error writing feature-split-event-channels\n");
/* Multi-queue support: This is an optional feature. */
err = xenbus_printf(XBT_NIL, dev->nodename,
"multi-queue-max-queues", "%u", xenvif_max_queues);
if (err)
pr_debug("Error writing multi-queue-max-queues\n");
err = xenbus_printf(XBT_NIL, dev->nodename,
"feature-ctrl-ring",
"%u", true);
if (err)
pr_debug("Error writing feature-ctrl-ring\n");
backend_switch_state(be, XenbusStateInitWait);
script = xenbus_read(XBT_NIL, dev->nodename, "script", NULL);
if (IS_ERR(script)) {
err = PTR_ERR(script);
xenbus_dev_fatal(dev, err, "reading script");
goto fail;
}
be->hotplug_script = script;
/* This kicks hotplug scripts, so do it immediately. */
err = backend_create_xenvif(be);
if (err)
goto fail;
return 0;
abort_transaction:
xenbus_transaction_end(xbt, 1);
xenbus_dev_fatal(dev, err, "%s", message);
fail:
pr_debug("failed\n");
netback_remove(dev);
return err;
}
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
static const struct xenbus_device_id netback_ids[] = {
{ "vif" },
{ "" }
};
static struct xenbus_driver netback_driver = {
.ids = netback_ids,
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
.probe = netback_probe,
.remove = netback_remove,
.uevent = netback_uevent,
.otherend_changed = frontend_changed,
.allow_rebind = true,
};
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
int xenvif_xenbus_init(void)
{
return xenbus_register_backend(&netback_driver);
xen network backend driver netback is the host side counterpart to the frontend driver in drivers/net/xen-netfront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs and even Windows. The patch is based on the driver from the xen.git pvops kernel tree but has been put through the checkpatch.pl wringer plus several manual cleanup passes and review iterations. The driver has been moved from drivers/xen/netback to drivers/net/xen-netback. One major change from xen.git is that the guest transmit path (i.e. what looks like receive to netback) has been significantly reworked to remove the dependency on the out of tree PageForeign page flag (a core kernel patch which enables a per page destructor callback on the final put_page). This page flag was used in order to implement a grant map based transmit path (where guest pages are mapped directly into SKB frags). Instead this version of netback uses grant copy operations into regular memory belonging to the backend domain. Reinstating the grant map functionality is something which I would like to revisit in the future. Note that this driver depends on 2e820f58f7ad "xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers" which is in linux next via the "xen-two" tree and is intended for the 2.6.39 merge window: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/backends this branch has only that single commit since 2.6.38-rc2 and is safe for cross merging into the net branch. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-15 08:06:18 +08:00
}
void xenvif_xenbus_fini(void)
{
return xenbus_unregister_driver(&netback_driver);
}