LXR linux/tools/virtio/linux/virtio.h

   1#ifndef LINUX_VIRTIO_H
   2#define LINUX_VIRTIO_H
   3#include <linux/scatterlist.h>
   4#include <linux/kernel.h>
   5
   6/* TODO: empty stubs for now. Broken but enough for virtio_ring.c */
   7#define list_add_tail(a, b) do {} while (0)
   8#define list_del(a) do {} while (0)
   9
  10#define BIT_WORD(nr)            ((nr) / BITS_PER_LONG)
  11#define BITS_PER_BYTE           8
  12#define BITS_PER_LONG (sizeof(long) * BITS_PER_BYTE)
  13#define BIT_MASK(nr)            (1UL << ((nr) % BITS_PER_LONG))
  14
  15/* TODO: Not atomic as it should be:
  16 * we don't use this for anything important. */
  17static inline void clear_bit(int nr, volatile unsigned long *addr)
  18{
  19        unsigned long mask = BIT_MASK(nr);
  20        unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
  21
  22        *p &= ~mask;
  23}
  24
  25static inline int test_bit(int nr, const volatile unsigned long *addr)
  26{
  27        return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
  28}
  29/* end of stubs */
  30
  31struct virtio_device {
  32        void *dev;
  33        unsigned long features[1];
  34};
  35
  36struct virtqueue {
  37        /* TODO: commented as list macros are empty stubs for now.
  38         * Broken but enough for virtio_ring.c
  39         * struct list_head list; */
  40        void (*callback)(struct virtqueue *vq);
  41        const char *name;
  42        struct virtio_device *vdev;
  43        unsigned int index;
  44        unsigned int num_free;
  45        void *priv;
  46};
  47
  48/* Interfaces exported by virtio_ring. */
  49int virtqueue_add_sgs(struct virtqueue *vq,
  50                      struct scatterlist *sgs[],
  51                      unsigned int out_sgs,
  52                      unsigned int in_sgs,
  53                      void *data,
  54                      gfp_t gfp);
  55
  56int virtqueue_add_outbuf(struct virtqueue *vq,
  57                         struct scatterlist sg[], unsigned int num,
  58                         void *data,
  59                         gfp_t gfp);
  60
  61int virtqueue_add_inbuf(struct virtqueue *vq,
  62                        struct scatterlist sg[], unsigned int num,
  63                        void *data,
  64                        gfp_t gfp);
  65
  66void virtqueue_kick(struct virtqueue *vq);
  67
  68void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
  69
  70void virtqueue_disable_cb(struct virtqueue *vq);
  71
  72bool virtqueue_enable_cb(struct virtqueue *vq);
  73bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
  74
  75void *virtqueue_detach_unused_buf(struct virtqueue *vq);
  76struct virtqueue *vring_new_virtqueue(unsigned int index,
  77                                      unsigned int num,
  78                                      unsigned int vring_align,
  79                                      struct virtio_device *vdev,
  80                                      bool weak_barriers,
  81                                      void *pages,
  82                                      void (*notify)(struct virtqueue *vq),
  83                                      void (*callback)(struct virtqueue *vq),
  84                                      const char *name);
  85void vring_del_virtqueue(struct virtqueue *vq);
  86
  87#endif
  88