tools/virtio/linux/virtio.h

   1 #ifndef LINUX_VIRTIO_H
   2 #define LINUX_VIRTIO_H
   3
   4 #include <stdbool.h>
   5 #include <stdlib.h>
   6 #include <stddef.h>
   7 #include <stdio.h>
   8 #include <string.h>
   9 #include <assert.h>
  10
  11 #include <linux/types.h>
  12 #include <errno.h>
  13
  14 typedef unsigned long long dma_addr_t;
  15
  16 struct scatterlist {
  17         unsigned long   page_link;
  18         unsigned int    offset;
  19         unsigned int    length;
  20         dma_addr_t      dma_address;
  21 };
  22
  23 struct page {
  24         unsigned long long dummy;
  25 };
  26
  27 #define BUG_ON(__BUG_ON_cond) assert(!(__BUG_ON_cond))
  28
  29 /* Physical == Virtual */
  30 #define virt_to_phys(p) ((unsigned long)p)
  31 #define phys_to_virt(a) ((void *)(unsigned long)(a))
  32 /* Page address: Virtual / 4K */
  33 #define virt_to_page(p) ((struct page*)((virt_to_phys(p) / 4096) * \
  34                                         sizeof(struct page)))
  35 #define offset_in_page(p) (((unsigned long)p) % 4096)
  36 #define sg_phys(sg) ((sg->page_link & ~0x3) / sizeof(struct page) * 4096 + \
  37                      sg->offset)
  38 static inline void sg_mark_end(struct scatterlist *sg)
  39 {
  40         /*
  41          * Set termination bit, clear potential chain bit
  42          */
  43         sg->page_link |= 0x02;
  44         sg->page_link &= ~0x01;
  45 }
  46 static inline void sg_init_table(struct scatterlist *sgl, unsigned int nents)
  47 {
  48         memset(sgl, 0, sizeof(*sgl) * nents);
  49         sg_mark_end(&sgl[nents - 1]);
  50 }
  51 static inline void sg_assign_page(struct scatterlist *sg, struct page *page)
  52 {
  53         unsigned long page_link = sg->page_link & 0x3;
  54
  55         /*
  56          * In order for the low bit stealing approach to work, pages
  57          * must be aligned at a 32-bit boundary as a minimum.
  58          */
  59         BUG_ON((unsigned long) page & 0x03);
  60         sg->page_link = page_link | (unsigned long) page;
  61 }
  62
  63 static inline void sg_set_page(struct scatterlist *sg, struct page *page,
  64                                unsigned int len, unsigned int offset)
  65 {
  66         sg_assign_page(sg, page);
  67         sg->offset = offset;
  68         sg->length = len;
  69 }
  70
  71 static inline void sg_set_buf(struct scatterlist *sg, const void *buf,
  72                               unsigned int buflen)
  73 {
  74         sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
  75 }
  76
  77 static inline void sg_init_one(struct scatterlist *sg, const void *buf, unsigned int buflen)
  78 {
  79         sg_init_table(sg, 1);
  80         sg_set_buf(sg, buf, buflen);
  81 }
  82
  83 typedef __u16 u16;
  84
  85 typedef enum {
  86         GFP_KERNEL,
  87         GFP_ATOMIC,
  88 } gfp_t;
  89 typedef enum {
  90         IRQ_NONE,
  91         IRQ_HANDLED
  92 } irqreturn_t;
  93
  94 static inline void *kmalloc(size_t s, gfp_t gfp)
  95 {
  96         return malloc(s);
  97 }
  98
  99 static inline void kfree(void *p)
 100 {
 101         free(p);
 102 }
 103
 104 #define container_of(ptr, type, member) ({                      \
 105         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 106         (type *)( (char *)__mptr - offsetof(type,member) );})
 107
 108 #define uninitialized_var(x) x = x
 109
 110 # ifndef likely
 111 #  define likely(x)     (__builtin_expect(!!(x), 1))
 112 # endif
 113 # ifndef unlikely
 114 #  define unlikely(x)   (__builtin_expect(!!(x), 0))
 115 # endif
 116
 117 #define pr_err(format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 118 #ifdef DEBUG
 119 #define pr_debug(format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 120 #else
 121 #define pr_debug(format, ...) do {} while (0)
 122 #endif
 123 #define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 124 #define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 125
 126 /* TODO: empty stubs for now. Broken but enough for virtio_ring.c */
 127 #define list_add_tail(a, b) do {} while (0)
 128 #define list_del(a) do {} while (0)
 129
 130 #define BIT_WORD(nr)            ((nr) / BITS_PER_LONG)
 131 #define BITS_PER_BYTE           8
 132 #define BITS_PER_LONG (sizeof(long) * BITS_PER_BYTE)
 133 #define BIT_MASK(nr)            (1UL << ((nr) % BITS_PER_LONG))
 134 /* TODO: Not atomic as it should be:
 135  * we don't use this for anything important. */
 136 static inline void clear_bit(int nr, volatile unsigned long *addr)
 137 {
 138         unsigned long mask = BIT_MASK(nr);
 139         unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 140
 141         *p &= ~mask;
 142 }
 143
 144 static inline int test_bit(int nr, const volatile unsigned long *addr)
 145 {
 146         return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
 147 }
 148
 149 /* The only feature we care to support */
 150 #define virtio_has_feature(dev, feature) \
 151         test_bit((feature), (dev)->features)
 152 /* end of stubs */
 153
 154 struct virtio_device {
 155         void *dev;
 156         unsigned long features[1];
 157 };
 158
 159 struct virtqueue {
 160         /* TODO: commented as list macros are empty stubs for now.
 161          * Broken but enough for virtio_ring.c
 162          * struct list_head list; */
 163         void (*callback)(struct virtqueue *vq);
 164         const char *name;
 165         struct virtio_device *vdev;
 166         void *priv;
 167 };
 168
 169 #define EXPORT_SYMBOL_GPL(__EXPORT_SYMBOL_GPL_name) \
 170         void __EXPORT_SYMBOL_GPL##__EXPORT_SYMBOL_GPL_name() { \
 171 }
 172 #define MODULE_LICENSE(__MODULE_LICENSE_value) \
 173         const char *__MODULE_LICENSE_name = __MODULE_LICENSE_value
 174
 175 #define CONFIG_SMP
 176
 177 #if defined(__i386__) || defined(__x86_64__)
 178 #define barrier() asm volatile("" ::: "memory")
 179 #define mb() __sync_synchronize()
 180
 181 #define smp_mb()        mb()
 182 # define smp_rmb()      barrier()
 183 # define smp_wmb()      barrier()
 184 #else
 185 #error Please fill in barrier macros
 186 #endif
 187
 188 /* Interfaces exported by virtio_ring. */
 189 int virtqueue_add_buf(struct virtqueue *vq,
 190                       struct scatterlist sg[],
 191                       unsigned int out_num,
 192                       unsigned int in_num,
 193                       void *data,
 194                       gfp_t gfp);
 195
 196 void virtqueue_kick(struct virtqueue *vq);
 197
 198 void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
 199
 200 void virtqueue_disable_cb(struct virtqueue *vq);
 201
 202 bool virtqueue_enable_cb(struct virtqueue *vq);
 203
 204 void *virtqueue_detach_unused_buf(struct virtqueue *vq);
 205 struct virtqueue *vring_new_virtqueue(unsigned int num,
 206                                       unsigned int vring_align,
 207                                       struct virtio_device *vdev,
 208                                       bool weak_barriers,
 209                                       void *pages,
 210                                       void (*notify)(struct virtqueue *vq),
 211                                       void (*callback)(struct virtqueue *vq),
 212                                       const char *name);
 213 void vring_del_virtqueue(struct virtqueue *vq);
 214
 215 #endif