drivers/vhost/net.c

File Facts

System

Linux kernel

Corpus path

drivers/vhost/net.c

Extension

.c

Size

48288 bytes

Lines

1911

Domain

Driver Families

Bucket

drivers/vhost

Inferred role

Driver Families: operation-table or driver-model contract

Status

pattern implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/compat.h
• linux/eventfd.h
• linux/vhost.h
• linux/virtio_net.h
• linux/miscdevice.h
• linux/module.h
• linux/moduleparam.h
• linux/mutex.h
• linux/workqueue.h
• linux/file.h
• linux/slab.h
• linux/sched/clock.h
• linux/sched/signal.h
• linux/vmalloc.h
• linux/net.h
• linux/if_packet.h
• linux/if_arp.h
• linux/if_tun.h
• linux/if_macvlan.h
• linux/if_tap.h
• linux/if_vlan.h
• linux/skb_array.h
• linux/skbuff.h
• net/sock.h
• net/xdp.h
• vhost.h

Detected Declarations

• struct vhost_net_ubuf_ref
• struct vhost_net_buf
• struct vhost_net_virtqueue
• struct vhost_net
• function vhost_net_buf_get_size
• function vhost_net_buf_is_empty
• function vhost_net_buf_produce
• function vhost_net_buf_unproduce
• function vhost_net_buf_peek_len
• function vhost_net_buf_peek
• function vhost_net_buf_init
• function vhost_net_enable_zcopy
• function vhost_net_ubuf_alloc
• function vhost_net_ubuf_put
• function vhost_net_ubuf_put_and_wait
• function vhost_net_ubuf_put_wait_and_free
• function vhost_net_clear_ubuf_info
• function vhost_net_set_ubuf_info
• function vhost_net_vq_reset
• function vhost_net_tx_packet
• function vhost_net_tx_err
• function vhost_net_tx_select_zcopy
• function vhost_sock_zcopy
• function vhost_sock_xdp
• function vhost_zerocopy_signal_used
• function vhost_zerocopy_complete
• function busy_clock
• function vhost_can_busy_poll
• function vhost_net_disable_vq
• function vhost_net_enable_vq
• function vhost_net_signal_used
• function vhost_tx_batch
• function sock_has_rx_data
• function vhost_net_busy_poll_try_queue
• function vhost_net_busy_poll
• function vhost_net_tx_get_vq_desc
• function vhost_exceeds_maxpend
• function init_iov_iter
• function get_tx_bufs
• function tx_can_batch
• function vhost_net_build_xdp
• function handle_tx_copy
• function handle_tx_zerocopy
• function handle_tx
• function peek_head_len
• function vhost_net_rx_peek_head_len
• function get_rx_bufs
• function handle_rx

Annotated Snippet

static const struct file_operations vhost_net_fops = {
	.owner          = THIS_MODULE,
	.release        = vhost_net_release,
	.read_iter      = vhost_net_chr_read_iter,
	.write_iter     = vhost_net_chr_write_iter,
	.poll           = vhost_net_chr_poll,
	.unlocked_ioctl = vhost_net_ioctl,
	.compat_ioctl   = compat_ptr_ioctl,
	.open           = vhost_net_open,
	.llseek		= noop_llseek,
};

static struct miscdevice vhost_net_misc = {
	.minor = VHOST_NET_MINOR,
	.name = "vhost-net",
	.fops = &vhost_net_fops,
};

static int __init vhost_net_init(void)
{
	if (experimental_zcopytx)
		vhost_net_enable_zcopy(VHOST_NET_VQ_TX);
	return misc_register(&vhost_net_misc);
}
module_init(vhost_net_init);

static void __exit vhost_net_exit(void)
{
	misc_deregister(&vhost_net_misc);
}
module_exit(vhost_net_exit);

MODULE_VERSION("0.0.1");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Michael S. Tsirkin");
MODULE_DESCRIPTION("Host kernel accelerator for virtio net");
MODULE_ALIAS_MISCDEV(VHOST_NET_MINOR);
MODULE_ALIAS("devname:vhost-net");

Annotation

• Immediate include surface: `linux/compat.h`, `linux/eventfd.h`, `linux/vhost.h`, `linux/virtio_net.h`, `linux/miscdevice.h`, `linux/module.h`, `linux/moduleparam.h`, `linux/mutex.h`.
• Detected declarations: `struct vhost_net_ubuf_ref`, `struct vhost_net_buf`, `struct vhost_net_virtqueue`, `struct vhost_net`, `function vhost_net_buf_get_size`, `function vhost_net_buf_is_empty`, `function vhost_net_buf_produce`, `function vhost_net_buf_unproduce`, `function vhost_net_buf_peek_len`, `function vhost_net_buf_peek`.
• Atlas domain: Driver Families / drivers/vhost.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.