xref: /qemu/include/hw/virtio/virtio.h (revision 3c185597c86b8cd0a07c46e7a5bd5aac28bb7200)
1 /*
2  * Virtio Support
3  *
4  * Copyright IBM, Corp. 2007
5  *
6  * Authors:
7  *  Anthony Liguori   <aliguori@us.ibm.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2.  See
10  * the COPYING file in the top-level directory.
11  *
12  */
13 
14 #ifndef _QEMU_VIRTIO_H
15 #define _QEMU_VIRTIO_H
16 
17 #include "hw/hw.h"
18 #include "net/net.h"
19 #include "hw/qdev.h"
20 #include "sysemu/sysemu.h"
21 #include "qemu/event_notifier.h"
22 #include "standard-headers/linux/virtio_config.h"
23 #include "standard-headers/linux/virtio_ring.h"
24 
25 /* A guest should never accept this.  It implies negotiation is broken. */
26 #define VIRTIO_F_BAD_FEATURE		30
27 
28 struct VirtQueue;
29 
30 static inline hwaddr vring_align(hwaddr addr,
31                                              unsigned long align)
32 {
33     return (addr + align - 1) & ~(align - 1);
34 }
35 
36 typedef struct VirtQueue VirtQueue;
37 
38 #define VIRTQUEUE_MAX_SIZE 1024
39 
40 typedef struct VirtQueueElement
41 {
42     unsigned int index;
43     unsigned int out_num;
44     unsigned int in_num;
45     hwaddr in_addr[VIRTQUEUE_MAX_SIZE];
46     hwaddr out_addr[VIRTQUEUE_MAX_SIZE];
47     struct iovec in_sg[VIRTQUEUE_MAX_SIZE];
48     struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
49 } VirtQueueElement;
50 
51 #define VIRTIO_QUEUE_MAX 1024
52 
53 #define VIRTIO_NO_VECTOR 0xffff
54 
55 #define TYPE_VIRTIO_DEVICE "virtio-device"
56 #define VIRTIO_DEVICE_GET_CLASS(obj) \
57         OBJECT_GET_CLASS(VirtioDeviceClass, obj, TYPE_VIRTIO_DEVICE)
58 #define VIRTIO_DEVICE_CLASS(klass) \
59         OBJECT_CLASS_CHECK(VirtioDeviceClass, klass, TYPE_VIRTIO_DEVICE)
60 #define VIRTIO_DEVICE(obj) \
61         OBJECT_CHECK(VirtIODevice, (obj), TYPE_VIRTIO_DEVICE)
62 
63 enum virtio_device_endian {
64     VIRTIO_DEVICE_ENDIAN_UNKNOWN,
65     VIRTIO_DEVICE_ENDIAN_LITTLE,
66     VIRTIO_DEVICE_ENDIAN_BIG,
67 };
68 
69 struct VirtIODevice
70 {
71     DeviceState parent_obj;
72     const char *name;
73     uint8_t status;
74     uint8_t isr;
75     uint16_t queue_sel;
76     uint64_t guest_features;
77     uint64_t host_features;
78     size_t config_len;
79     void *config;
80     uint16_t config_vector;
81     int nvectors;
82     VirtQueue *vq;
83     uint16_t device_id;
84     bool vm_running;
85     VMChangeStateEntry *vmstate;
86     char *bus_name;
87     uint8_t device_endian;
88     QLIST_HEAD(, VirtQueue) *vector_queues;
89 };
90 
91 typedef struct VirtioDeviceClass {
92     /*< private >*/
93     DeviceClass parent;
94     /*< public >*/
95 
96     /* This is what a VirtioDevice must implement */
97     DeviceRealize realize;
98     DeviceUnrealize unrealize;
99     uint64_t (*get_features)(VirtIODevice *vdev, uint64_t requested_features);
100     uint64_t (*bad_features)(VirtIODevice *vdev);
101     void (*set_features)(VirtIODevice *vdev, uint64_t val);
102     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
103     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
104     void (*reset)(VirtIODevice *vdev);
105     void (*set_status)(VirtIODevice *vdev, uint8_t val);
106     /* Test and clear event pending status.
107      * Should be called after unmask to avoid losing events.
108      * If backend does not support masking,
109      * must check in frontend instead.
110      */
111     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
112     /* Mask/unmask events from this vq. Any events reported
113      * while masked will become pending.
114      * If backend does not support masking,
115      * must mask in frontend instead.
116      */
117     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
118     void (*save)(VirtIODevice *vdev, QEMUFile *f);
119     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
120 } VirtioDeviceClass;
121 
122 void virtio_instance_init_common(Object *proxy_obj, void *data,
123                                  size_t vdev_size, const char *vdev_name);
124 
125 void virtio_init(VirtIODevice *vdev, const char *name,
126                          uint16_t device_id, size_t config_size);
127 void virtio_cleanup(VirtIODevice *vdev);
128 
129 /* Set the child bus name. */
130 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
131 
132 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
133                             void (*handle_output)(VirtIODevice *,
134                                                   VirtQueue *));
135 
136 void virtio_del_queue(VirtIODevice *vdev, int n);
137 
138 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
139                     unsigned int len);
140 void virtqueue_flush(VirtQueue *vq, unsigned int count);
141 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
142                     unsigned int len, unsigned int idx);
143 
144 void virtqueue_map_sg(struct iovec *sg, hwaddr *addr,
145     size_t num_sg, int is_write);
146 int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem);
147 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
148                           unsigned int out_bytes);
149 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
150                                unsigned int *out_bytes,
151                                unsigned max_in_bytes, unsigned max_out_bytes);
152 
153 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
154 
155 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
156 
157 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
158 
159 void virtio_notify_config(VirtIODevice *vdev);
160 
161 void virtio_queue_set_notification(VirtQueue *vq, int enable);
162 
163 int virtio_queue_ready(VirtQueue *vq);
164 
165 int virtio_queue_empty(VirtQueue *vq);
166 
167 /* Host binding interface.  */
168 
169 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
170 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
171 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
172 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
173 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
174 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
175 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
176 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
177 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
178 int virtio_queue_get_num(VirtIODevice *vdev, int n);
179 int virtio_get_num_queues(VirtIODevice *vdev);
180 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
181 void virtio_queue_notify(VirtIODevice *vdev, int n);
182 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
183 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
184 void virtio_set_status(VirtIODevice *vdev, uint8_t val);
185 void virtio_reset(void *opaque);
186 void virtio_update_irq(VirtIODevice *vdev);
187 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
188 
189 /* Base devices.  */
190 typedef struct VirtIOBlkConf VirtIOBlkConf;
191 struct virtio_net_conf;
192 typedef struct virtio_serial_conf virtio_serial_conf;
193 typedef struct virtio_input_conf virtio_input_conf;
194 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
195 typedef struct VirtIORNGConf VirtIORNGConf;
196 
197 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
198     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
199                       VIRTIO_RING_F_INDIRECT_DESC, true), \
200     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
201                       VIRTIO_RING_F_EVENT_IDX, true),     \
202     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
203                       VIRTIO_F_NOTIFY_ON_EMPTY, true)
204 
205 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
206 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
207 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
208 hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n);
209 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
210 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
211 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
212 hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n);
213 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
214 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
215 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
216 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
217 uint16_t virtio_get_queue_index(VirtQueue *vq);
218 int virtio_queue_get_id(VirtQueue *vq);
219 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
220 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
221                                                 bool with_irqfd);
222 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
223 void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign,
224                                                bool set_handler);
225 void virtio_queue_notify_vq(VirtQueue *vq);
226 void virtio_irq(VirtQueue *vq);
227 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
228 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
229 
230 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
231 {
232     assert(fbit < 64);
233     *features |= (1ULL << fbit);
234 }
235 
236 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
237 {
238     assert(fbit < 64);
239     *features &= ~(1ULL << fbit);
240 }
241 
242 static inline bool __virtio_has_feature(uint64_t features, unsigned int fbit)
243 {
244     assert(fbit < 64);
245     return !!(features & (1ULL << fbit));
246 }
247 
248 static inline bool virtio_has_feature(VirtIODevice *vdev, unsigned int fbit)
249 {
250     return __virtio_has_feature(vdev->guest_features, fbit);
251 }
252 
253 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
254 {
255     if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
256         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
257         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
258     }
259     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
260     return false;
261 }
262 #endif
263