Initial import

1 files changed, 206 insertions, 0 deletions

diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
new file mode 100644
index 000000000..8c1c79290
--- /dev/null
+++ b/drivers/vhost/vhost.h
@@ -0,0 +1,206 @@
+#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/uio.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_ring.h>
+#include <linux/atomic.h>
+
+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);
+int 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);
+void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work);
+long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
+
+struct vhost_log {
+	u64 addr;
+	u64 len;
+};
+
+/* 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];
+	struct iovec *indirect;
+	struct vring_used_elem *heads;
+	/* Protected by virtqueue mutex. */
+	struct vhost_memory *memory;
+	void *private_data;
+	u64 acked_features;
+	/* Log write descriptors */
+	void __user *log_base;
+	struct vhost_log *log;
+};
+
+struct vhost_dev {
+	struct vhost_memory *memory;
+	struct mm_struct *mm;
+	struct mutex mutex;
+	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;
+};
+
+void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs);
+long vhost_dev_set_owner(struct vhost_dev *dev);
+bool vhost_dev_has_owner(struct vhost_dev *dev);
+long vhost_dev_check_owner(struct vhost_dev *);
+struct vhost_memory *vhost_dev_reset_owner_prepare(void);
+void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *);
+void vhost_dev_cleanup(struct vhost_dev *, bool locked);
+void vhost_dev_stop(struct vhost_dev *);
+long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp);
+long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
+int vhost_vq_access_ok(struct vhost_virtqueue *vq);
+int vhost_log_access_ok(struct vhost_dev *);
+
+int vhost_get_vq_desc(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);
+
+#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),
+};
+
+static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit)
+{
+	return vq->acked_features & (1ULL << bit);
+}
+
+/* Memory accessors */
+static inline u16 vhost16_to_cpu(struct vhost_virtqueue *vq, __virtio16 val)
+{
+	return __virtio16_to_cpu(vhost_has_feature(vq, VIRTIO_F_VERSION_1), val);
+}
+
+static inline __virtio16 cpu_to_vhost16(struct vhost_virtqueue *vq, u16 val)
+{
+	return __cpu_to_virtio16(vhost_has_feature(vq, VIRTIO_F_VERSION_1), val);
+}
+
+static inline u32 vhost32_to_cpu(struct vhost_virtqueue *vq, __virtio32 val)
+{
+	return __virtio32_to_cpu(vhost_has_feature(vq, VIRTIO_F_VERSION_1), val);
+}
+
+static inline __virtio32 cpu_to_vhost32(struct vhost_virtqueue *vq, u32 val)
+{
+	return __cpu_to_virtio32(vhost_has_feature(vq, VIRTIO_F_VERSION_1), val);
+}
+
+static inline u64 vhost64_to_cpu(struct vhost_virtqueue *vq, __virtio64 val)
+{
+	return __virtio64_to_cpu(vhost_has_feature(vq, VIRTIO_F_VERSION_1), val);
+}
+
+static inline __virtio64 cpu_to_vhost64(struct vhost_virtqueue *vq, u64 val)
+{
+	return __cpu_to_virtio64(vhost_has_feature(vq, VIRTIO_F_VERSION_1), val);
+}
+#endif