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. */ 17 static 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 25 static 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 31 struct virtio_device { 32 void *dev; 33 unsigned long features[1]; 34 }; 35 36 struct 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. */ 49 int 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 56 int virtqueue_add_outbuf(struct virtqueue *vq, 57 struct scatterlist sg[], unsigned int num, 58 void *data, 59 gfp_t gfp); 60 61 int virtqueue_add_inbuf(struct virtqueue *vq, 62 struct scatterlist sg[], unsigned int num, 63 void *data, 64 gfp_t gfp); 65 66 bool virtqueue_kick(struct virtqueue *vq); 67 68 void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len); 69 70 void virtqueue_disable_cb(struct virtqueue *vq); 71 72 bool virtqueue_enable_cb(struct virtqueue *vq); 73 bool virtqueue_enable_cb_delayed(struct virtqueue *vq); 74 75 void *virtqueue_detach_unused_buf(struct virtqueue *vq); 76 struct 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 bool (*notify)(struct virtqueue *vq), 83 void (*callback)(struct virtqueue *vq), 84 const char *name); 85 void vring_del_virtqueue(struct virtqueue *vq); 86 87 #endif 88