diff options
Diffstat (limited to 'drivers/vhost/vhost.h')
| -rw-r--r-- | drivers/vhost/vhost.h | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 8e03379dd30f..14c9abf0d800 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -13,6 +13,11 @@ #include <linux/virtio_ring.h> #include <asm/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; @@ -50,6 +55,18 @@ struct vhost_log { 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; @@ -114,6 +131,16 @@ struct vhost_virtqueue { /* 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 { @@ -147,6 +174,7 @@ int vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *, 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); @@ -160,6 +188,8 @@ 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(void *arg); +int vhost_zerocopy_signal_used(struct vhost_virtqueue *vq); #define vq_err(vq, fmt, ...) do { \ pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \ @@ -186,4 +216,6 @@ static inline int vhost_has_feature(struct vhost_dev *dev, int bit) return acked_features & (1 << bit); } +void vhost_enable_zcopy(int vq); + #endif |