226 строки
6.9 KiB
C
226 строки
6.9 KiB
C
#ifndef _VHOST_H
|
|
#define _VHOST_H
|
|
|
|
#include <linux/eventfd.h>
|
|
#include <linux/vhost.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/poll.h>
|
|
#include <linux/file.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/uio.h>
|
|
#include <linux/virtio_config.h>
|
|
#include <linux/virtio_ring.h>
|
|
#include <linux/atomic.h>
|
|
|
|
/* This is for zerocopy, used buffer len is set to 1 when lower device DMA
|
|
* done */
|
|
#define VHOST_DMA_DONE_LEN 1
|
|
#define VHOST_DMA_CLEAR_LEN 0
|
|
|
|
struct vhost_device;
|
|
|
|
struct vhost_work;
|
|
typedef void (*vhost_work_fn_t)(struct vhost_work *work);
|
|
|
|
struct vhost_work {
|
|
struct list_head node;
|
|
vhost_work_fn_t fn;
|
|
wait_queue_head_t done;
|
|
int flushing;
|
|
unsigned queue_seq;
|
|
unsigned done_seq;
|
|
};
|
|
|
|
/* Poll a file (eventfd or socket) */
|
|
/* Note: there's nothing vhost specific about this structure. */
|
|
struct vhost_poll {
|
|
poll_table table;
|
|
wait_queue_head_t *wqh;
|
|
wait_queue_t wait;
|
|
struct vhost_work work;
|
|
unsigned long mask;
|
|
struct vhost_dev *dev;
|
|
};
|
|
|
|
void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);
|
|
void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work);
|
|
|
|
void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
|
|
unsigned long mask, struct vhost_dev *dev);
|
|
void vhost_poll_start(struct vhost_poll *poll, struct file *file);
|
|
void vhost_poll_stop(struct vhost_poll *poll);
|
|
void vhost_poll_flush(struct vhost_poll *poll);
|
|
void vhost_poll_queue(struct vhost_poll *poll);
|
|
|
|
struct vhost_log {
|
|
u64 addr;
|
|
u64 len;
|
|
};
|
|
|
|
struct vhost_virtqueue;
|
|
|
|
struct vhost_ubuf_ref {
|
|
struct kref kref;
|
|
wait_queue_head_t wait;
|
|
struct vhost_virtqueue *vq;
|
|
};
|
|
|
|
struct vhost_ubuf_ref *vhost_ubuf_alloc(struct vhost_virtqueue *, bool zcopy);
|
|
void vhost_ubuf_put(struct vhost_ubuf_ref *);
|
|
void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *);
|
|
|
|
/* The virtqueue structure describes a queue attached to a device. */
|
|
struct vhost_virtqueue {
|
|
struct vhost_dev *dev;
|
|
|
|
/* The actual ring of buffers. */
|
|
struct mutex mutex;
|
|
unsigned int num;
|
|
struct vring_desc __user *desc;
|
|
struct vring_avail __user *avail;
|
|
struct vring_used __user *used;
|
|
struct file *kick;
|
|
struct file *call;
|
|
struct file *error;
|
|
struct eventfd_ctx *call_ctx;
|
|
struct eventfd_ctx *error_ctx;
|
|
struct eventfd_ctx *log_ctx;
|
|
|
|
struct vhost_poll poll;
|
|
|
|
/* The routine to call when the Guest pings us, or timeout. */
|
|
vhost_work_fn_t handle_kick;
|
|
|
|
/* Last available index we saw. */
|
|
u16 last_avail_idx;
|
|
|
|
/* Caches available index value from user. */
|
|
u16 avail_idx;
|
|
|
|
/* Last index we used. */
|
|
u16 last_used_idx;
|
|
|
|
/* Used flags */
|
|
u16 used_flags;
|
|
|
|
/* Last used index value we have signalled on */
|
|
u16 signalled_used;
|
|
|
|
/* Last used index value we have signalled on */
|
|
bool signalled_used_valid;
|
|
|
|
/* Log writes to used structure. */
|
|
bool log_used;
|
|
u64 log_addr;
|
|
|
|
struct iovec iov[UIO_MAXIOV];
|
|
/* hdr is used to store the virtio header.
|
|
* Since each iovec has >= 1 byte length, we never need more than
|
|
* header length entries to store the header. */
|
|
struct iovec hdr[sizeof(struct virtio_net_hdr_mrg_rxbuf)];
|
|
struct iovec *indirect;
|
|
size_t vhost_hlen;
|
|
size_t sock_hlen;
|
|
struct vring_used_elem *heads;
|
|
/* We use a kind of RCU to access private pointer.
|
|
* All readers access it from worker, which makes it possible to
|
|
* flush the vhost_work instead of synchronize_rcu. Therefore readers do
|
|
* not need to call rcu_read_lock/rcu_read_unlock: the beginning of
|
|
* vhost_work execution acts instead of rcu_read_lock() and the end of
|
|
* vhost_work execution acts instead of rcu_read_unlock().
|
|
* Writers use virtqueue mutex. */
|
|
void __rcu *private_data;
|
|
/* Log write descriptors */
|
|
void __user *log_base;
|
|
struct vhost_log *log;
|
|
/* vhost zerocopy support fields below: */
|
|
/* last used idx for outstanding DMA zerocopy buffers */
|
|
int upend_idx;
|
|
/* first used idx for DMA done zerocopy buffers */
|
|
int done_idx;
|
|
/* an array of userspace buffers info */
|
|
struct ubuf_info *ubuf_info;
|
|
/* Reference counting for outstanding ubufs.
|
|
* Protected by vq mutex. Writers must also take device mutex. */
|
|
struct vhost_ubuf_ref *ubufs;
|
|
};
|
|
|
|
struct vhost_dev {
|
|
/* Readers use RCU to access memory table pointer
|
|
* log base pointer and features.
|
|
* Writers use mutex below.*/
|
|
struct vhost_memory __rcu *memory;
|
|
struct mm_struct *mm;
|
|
struct mutex mutex;
|
|
unsigned acked_features;
|
|
struct vhost_virtqueue *vqs;
|
|
int nvqs;
|
|
struct file *log_file;
|
|
struct eventfd_ctx *log_ctx;
|
|
spinlock_t work_lock;
|
|
struct list_head work_list;
|
|
struct task_struct *worker;
|
|
};
|
|
|
|
long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue *vqs, int nvqs);
|
|
long vhost_dev_check_owner(struct vhost_dev *);
|
|
long vhost_dev_reset_owner(struct vhost_dev *);
|
|
void vhost_dev_cleanup(struct vhost_dev *, bool locked);
|
|
long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, unsigned long arg);
|
|
int vhost_vq_access_ok(struct vhost_virtqueue *vq);
|
|
int vhost_log_access_ok(struct vhost_dev *);
|
|
|
|
int vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
|
|
struct iovec iov[], unsigned int iov_count,
|
|
unsigned int *out_num, unsigned int *in_num,
|
|
struct vhost_log *log, unsigned int *log_num);
|
|
void vhost_discard_vq_desc(struct vhost_virtqueue *, int n);
|
|
|
|
int vhost_init_used(struct vhost_virtqueue *);
|
|
int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
|
|
int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads,
|
|
unsigned count);
|
|
void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *,
|
|
unsigned int id, int len);
|
|
void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
|
|
struct vring_used_elem *heads, unsigned count);
|
|
void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
|
|
void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
|
|
bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
|
|
|
|
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
|
|
unsigned int log_num, u64 len);
|
|
void vhost_zerocopy_callback(struct ubuf_info *);
|
|
int vhost_zerocopy_signal_used(struct vhost_virtqueue *vq);
|
|
|
|
#define vq_err(vq, fmt, ...) do { \
|
|
pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
|
|
if ((vq)->error_ctx) \
|
|
eventfd_signal((vq)->error_ctx, 1);\
|
|
} while (0)
|
|
|
|
enum {
|
|
VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
|
|
(1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
|
|
(1ULL << VIRTIO_RING_F_EVENT_IDX) |
|
|
(1ULL << VHOST_F_LOG_ALL),
|
|
VHOST_NET_FEATURES = VHOST_FEATURES |
|
|
(1ULL << VHOST_NET_F_VIRTIO_NET_HDR) |
|
|
(1ULL << VIRTIO_NET_F_MRG_RXBUF),
|
|
};
|
|
|
|
static inline int vhost_has_feature(struct vhost_dev *dev, int bit)
|
|
{
|
|
unsigned acked_features;
|
|
|
|
/* TODO: check that we are running from vhost_worker or dev mutex is
|
|
* held? */
|
|
acked_features = rcu_dereference_index_check(dev->acked_features, 1);
|
|
return acked_features & (1 << bit);
|
|
}
|
|
|
|
void vhost_enable_zcopy(int vq);
|
|
|
|
#endif
|