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1185 lines
29 KiB
1185 lines
29 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
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* Xenbus code for netif backend |
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* |
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* Copyright (C) 2005 Rusty Russell <[email protected]> |
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* Copyright (C) 2005 XenSource Ltd |
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*/ |
|
|
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#include "common.h" |
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#include <linux/vmalloc.h> |
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#include <linux/rtnetlink.h> |
|
|
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static int connect_data_rings(struct backend_info *be, |
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struct xenvif_queue *queue); |
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static void connect(struct backend_info *be); |
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static int read_xenbus_vif_flags(struct backend_info *be); |
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static int backend_create_xenvif(struct backend_info *be); |
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static void unregister_hotplug_status_watch(struct backend_info *be); |
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static void xen_unregister_watchers(struct xenvif *vif); |
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static void set_backend_state(struct backend_info *be, |
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enum xenbus_state state); |
|
|
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#ifdef CONFIG_DEBUG_FS |
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struct dentry *xen_netback_dbg_root = NULL; |
|
|
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static int xenvif_read_io_ring(struct seq_file *m, void *v) |
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{ |
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struct xenvif_queue *queue = m->private; |
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struct xen_netif_tx_back_ring *tx_ring = &queue->tx; |
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struct xen_netif_rx_back_ring *rx_ring = &queue->rx; |
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struct netdev_queue *dev_queue; |
|
|
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if (tx_ring->sring) { |
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struct xen_netif_tx_sring *sring = tx_ring->sring; |
|
|
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seq_printf(m, "Queue %d\nTX: nr_ents %u\n", queue->id, |
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tx_ring->nr_ents); |
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seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n", |
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sring->req_prod, |
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sring->req_prod - sring->rsp_prod, |
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tx_ring->req_cons, |
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tx_ring->req_cons - sring->rsp_prod, |
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sring->req_event, |
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sring->req_event - sring->rsp_prod); |
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seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n", |
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sring->rsp_prod, |
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tx_ring->rsp_prod_pvt, |
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tx_ring->rsp_prod_pvt - sring->rsp_prod, |
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sring->rsp_event, |
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sring->rsp_event - sring->rsp_prod); |
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seq_printf(m, "pending prod %u pending cons %u nr_pending_reqs %u\n", |
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queue->pending_prod, |
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queue->pending_cons, |
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nr_pending_reqs(queue)); |
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seq_printf(m, "dealloc prod %u dealloc cons %u dealloc_queue %u\n\n", |
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queue->dealloc_prod, |
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queue->dealloc_cons, |
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queue->dealloc_prod - queue->dealloc_cons); |
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} |
|
|
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if (rx_ring->sring) { |
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struct xen_netif_rx_sring *sring = rx_ring->sring; |
|
|
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seq_printf(m, "RX: nr_ents %u\n", rx_ring->nr_ents); |
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seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n", |
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sring->req_prod, |
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sring->req_prod - sring->rsp_prod, |
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rx_ring->req_cons, |
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rx_ring->req_cons - sring->rsp_prod, |
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sring->req_event, |
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sring->req_event - sring->rsp_prod); |
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seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n\n", |
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sring->rsp_prod, |
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rx_ring->rsp_prod_pvt, |
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rx_ring->rsp_prod_pvt - sring->rsp_prod, |
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sring->rsp_event, |
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sring->rsp_event - sring->rsp_prod); |
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} |
|
|
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seq_printf(m, "NAPI state: %lx NAPI weight: %d TX queue len %u\n" |
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"Credit timer_pending: %d, credit: %lu, usec: %lu\n" |
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"remaining: %lu, expires: %lu, now: %lu\n", |
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queue->napi.state, queue->napi.weight, |
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skb_queue_len(&queue->tx_queue), |
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timer_pending(&queue->credit_timeout), |
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queue->credit_bytes, |
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queue->credit_usec, |
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queue->remaining_credit, |
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queue->credit_timeout.expires, |
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jiffies); |
|
|
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dev_queue = netdev_get_tx_queue(queue->vif->dev, queue->id); |
|
|
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seq_printf(m, "\nRx internal queue: len %u max %u pkts %u %s\n", |
|
queue->rx_queue_len, queue->rx_queue_max, |
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skb_queue_len(&queue->rx_queue), |
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netif_tx_queue_stopped(dev_queue) ? "stopped" : "running"); |
|
|
|
return 0; |
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} |
|
|
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#define XENVIF_KICK_STR "kick" |
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#define BUFFER_SIZE 32 |
|
|
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static ssize_t |
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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; |
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char write[BUFFER_SIZE]; |
|
|
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/* don't allow partial writes and check the length */ |
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if (*ppos != 0) |
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return 0; |
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if (count >= sizeof(write)) |
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return -ENOSPC; |
|
|
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len = simple_write_to_buffer(write, |
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sizeof(write) - 1, |
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ppos, |
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buf, |
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count); |
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if (len < 0) |
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return len; |
|
|
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write[len] = '\0'; |
|
|
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if (!strncmp(write, XENVIF_KICK_STR, sizeof(XENVIF_KICK_STR) - 1)) |
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xenvif_interrupt(0, (void *)queue); |
|
else { |
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pr_warn("Unknown command to io_ring_q%d. Available: kick\n", |
|
queue->id); |
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count = -EINVAL; |
|
} |
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return count; |
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} |
|
|
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static int xenvif_io_ring_open(struct inode *inode, struct file *filp) |
|
{ |
|
int ret; |
|
void *queue = NULL; |
|
|
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if (inode->i_private) |
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queue = inode->i_private; |
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ret = single_open(filp, xenvif_read_io_ring, queue); |
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filp->f_mode |= FMODE_PWRITE; |
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return ret; |
|
} |
|
|
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static const struct file_operations xenvif_dbg_io_ring_ops_fops = { |
|
.owner = THIS_MODULE, |
|
.open = xenvif_io_ring_open, |
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.read = seq_read, |
|
.llseek = seq_lseek, |
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.release = single_release, |
|
.write = xenvif_write_io_ring, |
|
}; |
|
|
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static int xenvif_ctrl_show(struct seq_file *m, void *v) |
|
{ |
|
struct xenvif *vif = m->private; |
|
|
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xenvif_dump_hash_info(vif, m); |
|
|
|
return 0; |
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} |
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DEFINE_SHOW_ATTRIBUTE(xenvif_ctrl); |
|
|
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static void xenvif_debugfs_addif(struct xenvif *vif) |
|
{ |
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int i; |
|
|
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vif->xenvif_dbg_root = debugfs_create_dir(vif->dev->name, |
|
xen_netback_dbg_root); |
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for (i = 0; i < vif->num_queues; ++i) { |
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char filename[sizeof("io_ring_q") + 4]; |
|
|
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snprintf(filename, sizeof(filename), "io_ring_q%d", i); |
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debugfs_create_file(filename, 0600, vif->xenvif_dbg_root, |
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&vif->queues[i], |
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&xenvif_dbg_io_ring_ops_fops); |
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} |
|
|
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if (vif->ctrl_irq) |
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debugfs_create_file("ctrl", 0400, vif->xenvif_dbg_root, vif, |
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&xenvif_ctrl_fops); |
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} |
|
|
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static void xenvif_debugfs_delif(struct xenvif *vif) |
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{ |
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debugfs_remove_recursive(vif->xenvif_dbg_root); |
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vif->xenvif_dbg_root = NULL; |
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} |
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#endif /* CONFIG_DEBUG_FS */ |
|
|
|
/* |
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* 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 |
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* scripts. |
|
*/ |
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static int netback_uevent(struct xenbus_device *xdev, |
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struct kobj_uevent_env *env) |
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{ |
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struct backend_info *be = dev_get_drvdata(&xdev->dev); |
|
|
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if (!be) |
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return 0; |
|
|
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if (add_uevent_var(env, "script=%s", be->hotplug_script)) |
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return -ENOMEM; |
|
|
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if (!be->vif) |
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return 0; |
|
|
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return add_uevent_var(env, "vif=%s", be->vif->dev->name); |
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} |
|
|
|
|
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static int backend_create_xenvif(struct backend_info *be) |
|
{ |
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int err; |
|
long handle; |
|
struct xenbus_device *dev = be->dev; |
|
struct xenvif *vif; |
|
|
|
if (be->vif != NULL) |
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return 0; |
|
|
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err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle); |
|
if (err != 1) { |
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xenbus_dev_fatal(dev, err, "reading handle"); |
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return (err < 0) ? err : -EINVAL; |
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} |
|
|
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vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle); |
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if (IS_ERR(vif)) { |
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err = PTR_ERR(vif); |
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xenbus_dev_fatal(dev, err, "creating interface"); |
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return err; |
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} |
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be->vif = vif; |
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vif->be = be; |
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|
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kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE); |
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return 0; |
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} |
|
|
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static void backend_disconnect(struct backend_info *be) |
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{ |
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struct xenvif *vif = be->vif; |
|
|
|
if (vif) { |
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unsigned int num_queues = vif->num_queues; |
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unsigned int queue_index; |
|
|
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xen_unregister_watchers(vif); |
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#ifdef CONFIG_DEBUG_FS |
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xenvif_debugfs_delif(vif); |
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#endif /* CONFIG_DEBUG_FS */ |
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xenvif_disconnect_data(vif); |
|
|
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/* At this point some of the handlers may still be active |
|
* so we need to have additional synchronization here. |
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*/ |
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vif->num_queues = 0; |
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synchronize_net(); |
|
|
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for (queue_index = 0; queue_index < num_queues; ++queue_index) |
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xenvif_deinit_queue(&vif->queues[queue_index]); |
|
|
|
vfree(vif->queues); |
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vif->queues = NULL; |
|
|
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xenvif_disconnect_ctrl(vif); |
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} |
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} |
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|
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static void backend_connect(struct backend_info *be) |
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{ |
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if (be->vif) |
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connect(be); |
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} |
|
|
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static inline void backend_switch_state(struct backend_info *be, |
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enum xenbus_state state) |
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{ |
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struct xenbus_device *dev = be->dev; |
|
|
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pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state)); |
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be->state = state; |
|
|
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/* If we are waiting for a hotplug script then defer the |
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* actual xenbus state change. |
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*/ |
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if (!be->have_hotplug_status_watch) |
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xenbus_switch_state(dev, state); |
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} |
|
|
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/* Handle backend state transitions: |
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* |
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* The backend state starts in Initialising and the following transitions are |
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* allowed. |
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* |
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* Initialising -> InitWait -> Connected |
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* \ |
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* \ ^ \ | |
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* \ | \ | |
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* \ | \ | |
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* \ | \ | |
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* \ | \ | |
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* \ | \ | |
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* V | V V |
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* |
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* Closed <-> Closing |
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* |
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* The state argument specifies the eventual state of the backend and the |
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* function transitions to that state via the shortest path. |
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*/ |
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static void set_backend_state(struct backend_info *be, |
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enum xenbus_state state) |
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{ |
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while (be->state != state) { |
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switch (be->state) { |
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case XenbusStateInitialising: |
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switch (state) { |
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case XenbusStateInitWait: |
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case XenbusStateConnected: |
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case XenbusStateClosing: |
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backend_switch_state(be, XenbusStateInitWait); |
|
break; |
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case XenbusStateClosed: |
|
backend_switch_state(be, XenbusStateClosed); |
|
break; |
|
default: |
|
BUG(); |
|
} |
|
break; |
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case XenbusStateClosed: |
|
switch (state) { |
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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(); |
|
} |
|
} |
|
} |
|
|
|
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; |
|
} |
|
|
|
/* |
|
* 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)); |
|
|
|
be->frontend_state = frontend_state; |
|
|
|
switch (frontend_state) { |
|
case XenbusStateInitialising: |
|
set_backend_state(be, XenbusStateInitWait); |
|
break; |
|
|
|
case XenbusStateInitialised: |
|
break; |
|
|
|
case XenbusStateConnected: |
|
set_backend_state(be, XenbusStateConnected); |
|
break; |
|
|
|
case XenbusStateReconfiguring: |
|
read_xenbus_frontend_xdp(be, dev); |
|
xenbus_switch_state(dev, XenbusStateReconfigured); |
|
break; |
|
|
|
case XenbusStateClosing: |
|
set_backend_state(be, XenbusStateClosing); |
|
break; |
|
|
|
case XenbusStateClosed: |
|
set_backend_state(be, XenbusStateClosed); |
|
if (xenbus_dev_is_online(dev)) |
|
break; |
|
fallthrough; /* if not online */ |
|
case XenbusStateUnknown: |
|
set_backend_state(be, XenbusStateClosed); |
|
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); |
|
} |
|
|
|
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) |
|
{ |
|
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); |
|
|
|
/* Not interested in this watch anymore. */ |
|
unregister_hotplug_status_watch(be); |
|
xenbus_rm(XBT_NIL, be->dev->nodename, "hotplug-status"); |
|
} |
|
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; |
|
} |
|
|
|
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; |
|
|
|
/* 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; |
|
} |
|
|
|
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 */ |
|
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); |
|
|
|
unregister_hotplug_status_watch(be); |
|
if (xenbus_exists(XBT_NIL, dev->nodename, "hotplug-status")) { |
|
err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, |
|
NULL, hotplug_status_changed, |
|
"%s/%s", dev->nodename, |
|
"hotplug-status"); |
|
if (err) |
|
goto err; |
|
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; |
|
} |
|
|
|
|
|
static int connect_data_rings(struct backend_info *be, |
|
struct xenvif_queue *queue) |
|
{ |
|
struct xenbus_device *dev = be->dev; |
|
unsigned int num_queues = queue->vif->num_queues; |
|
unsigned long tx_ring_ref, rx_ring_ref; |
|
unsigned int tx_evtchn, rx_evtchn; |
|
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); |
|
} |
|
|
|
err = xenbus_gather(XBT_NIL, xspath, |
|
"tx-ring-ref", "%lu", &tx_ring_ref, |
|
"rx-ring-ref", "%lu", &rx_ring_ref, NULL); |
|
if (err) { |
|
xenbus_dev_fatal(dev, err, |
|
"reading %s/ring-ref", |
|
xspath); |
|
goto err; |
|
} |
|
|
|
/* 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; |
|
|
|
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; |
|
} |
|
|
|
vif->can_sg = !!xenbus_read_unsigned(dev->otherend, "feature-sg", 0); |
|
|
|
vif->gso_mask = 0; |
|
|
|
if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv4", 0)) |
|
vif->gso_mask |= GSO_BIT(TCPV4); |
|
|
|
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); |
|
|
|
read_xenbus_frontend_xdp(be, dev); |
|
|
|
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; |
|
} |
|
|
|
static const struct xenbus_device_id netback_ids[] = { |
|
{ "vif" }, |
|
{ "" } |
|
}; |
|
|
|
static struct xenbus_driver netback_driver = { |
|
.ids = netback_ids, |
|
.probe = netback_probe, |
|
.remove = netback_remove, |
|
.uevent = netback_uevent, |
|
.otherend_changed = frontend_changed, |
|
.allow_rebind = true, |
|
}; |
|
|
|
int xenvif_xenbus_init(void) |
|
{ |
|
return xenbus_register_backend(&netback_driver); |
|
} |
|
|
|
void xenvif_xenbus_fini(void) |
|
{ |
|
return xenbus_unregister_driver(&netback_driver); |
|
}
|
|
|