Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
14typedef unsigned long long dma_addr_t;
15
16struct scatterlist {
17 unsigned long page_link;
18 unsigned int offset;
19 unsigned int length;
20 dma_addr_t dma_address;
21};
22
23struct 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)
38static 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}
46static 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}
51static 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
63static 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
71static 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
77static 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
83typedef __u16 u16;
84
85typedef enum {
86 GFP_KERNEL,
87 GFP_ATOMIC,
88} gfp_t;
89typedef enum {
90 IRQ_NONE,
91 IRQ_HANDLED
92} irqreturn_t;
93
94static inline void *kmalloc(size_t s, gfp_t gfp)
95{
96 return malloc(s);
97}
98
99static 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. */
136static 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
144static 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
154struct virtio_device {
155 void *dev;
156 unsigned long features[1];
157};
158
159struct 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/* Weak barriers should be used. If not - it's a bug */
185# define rmb() abort()
186# define wmb() abort()
187#else
188#error Please fill in barrier macros
189#endif
190
191/* Interfaces exported by virtio_ring. */
192int virtqueue_add_buf(struct virtqueue *vq,
193 struct scatterlist sg[],
194 unsigned int out_num,
195 unsigned int in_num,
196 void *data,
197 gfp_t gfp);
198
199void virtqueue_kick(struct virtqueue *vq);
200
201void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
202
203void virtqueue_disable_cb(struct virtqueue *vq);
204
205bool virtqueue_enable_cb(struct virtqueue *vq);
206
207void *virtqueue_detach_unused_buf(struct virtqueue *vq);
208struct virtqueue *vring_new_virtqueue(unsigned int num,
209 unsigned int vring_align,
210 struct virtio_device *vdev,
211 bool weak_barriers,
212 void *pages,
213 void (*notify)(struct virtqueue *vq),
214 void (*callback)(struct virtqueue *vq),
215 const char *name);
216void vring_del_virtqueue(struct virtqueue *vq);
217
218#endif