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path: root/drivers/vhost/vhost.h
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Diffstat (limited to 'drivers/vhost/vhost.h')
-rw-r--r--drivers/vhost/vhost.h32
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