xref: /qemu/include/hw/virtio/virtio.h (revision 1a665855d7144bb3df382630a2b5e4039e95e466)
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 #define VIRTIO_LEGACY_FEATURES ((0x1ULL << VIRTIO_F_BAD_FEATURE) | \
29                                 (0x1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) | \
30                                 (0x1ULL << VIRTIO_F_ANY_LAYOUT))
31 
32 struct VirtQueue;
33 
34 static inline hwaddr vring_align(hwaddr addr,
35                                              unsigned long align)
36 {
37     return (addr + align - 1) & ~(align - 1);
38 }
39 
40 typedef struct VirtQueue VirtQueue;
41 
42 #define VIRTQUEUE_MAX_SIZE 1024
43 
44 typedef struct VirtQueueElement
45 {
46     unsigned int index;
47     unsigned int out_num;
48     unsigned int in_num;
49     hwaddr *in_addr;
50     hwaddr *out_addr;
51     struct iovec *in_sg;
52     struct iovec *out_sg;
53 } VirtQueueElement;
54 
55 #define VIRTIO_QUEUE_MAX 1024
56 
57 #define VIRTIO_NO_VECTOR 0xffff
58 
59 #define TYPE_VIRTIO_DEVICE "virtio-device"
60 #define VIRTIO_DEVICE_GET_CLASS(obj) \
61         OBJECT_GET_CLASS(VirtioDeviceClass, obj, TYPE_VIRTIO_DEVICE)
62 #define VIRTIO_DEVICE_CLASS(klass) \
63         OBJECT_CLASS_CHECK(VirtioDeviceClass, klass, TYPE_VIRTIO_DEVICE)
64 #define VIRTIO_DEVICE(obj) \
65         OBJECT_CHECK(VirtIODevice, (obj), TYPE_VIRTIO_DEVICE)
66 
67 enum virtio_device_endian {
68     VIRTIO_DEVICE_ENDIAN_UNKNOWN,
69     VIRTIO_DEVICE_ENDIAN_LITTLE,
70     VIRTIO_DEVICE_ENDIAN_BIG,
71 };
72 
73 struct VirtIODevice
74 {
75     DeviceState parent_obj;
76     const char *name;
77     uint8_t status;
78     uint8_t isr;
79     uint16_t queue_sel;
80     uint64_t guest_features;
81     uint64_t host_features;
82     size_t config_len;
83     void *config;
84     uint16_t config_vector;
85     uint32_t generation;
86     int nvectors;
87     VirtQueue *vq;
88     uint16_t device_id;
89     bool vm_running;
90     bool broken; /* device in invalid state, needs reset */
91     VMChangeStateEntry *vmstate;
92     char *bus_name;
93     uint8_t device_endian;
94     bool use_guest_notifier_mask;
95     QLIST_HEAD(, VirtQueue) *vector_queues;
96 };
97 
98 typedef struct VirtioDeviceClass {
99     /*< private >*/
100     DeviceClass parent;
101     /*< public >*/
102 
103     /* This is what a VirtioDevice must implement */
104     DeviceRealize realize;
105     DeviceUnrealize unrealize;
106     uint64_t (*get_features)(VirtIODevice *vdev,
107                              uint64_t requested_features,
108                              Error **errp);
109     uint64_t (*bad_features)(VirtIODevice *vdev);
110     void (*set_features)(VirtIODevice *vdev, uint64_t val);
111     int (*validate_features)(VirtIODevice *vdev);
112     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
113     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
114     void (*reset)(VirtIODevice *vdev);
115     void (*set_status)(VirtIODevice *vdev, uint8_t val);
116     /* Test and clear event pending status.
117      * Should be called after unmask to avoid losing events.
118      * If backend does not support masking,
119      * must check in frontend instead.
120      */
121     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
122     /* Mask/unmask events from this vq. Any events reported
123      * while masked will become pending.
124      * If backend does not support masking,
125      * must mask in frontend instead.
126      */
127     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
128     void (*save)(VirtIODevice *vdev, QEMUFile *f);
129     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
130 } VirtioDeviceClass;
131 
132 void virtio_instance_init_common(Object *proxy_obj, void *data,
133                                  size_t vdev_size, const char *vdev_name);
134 
135 void virtio_init(VirtIODevice *vdev, const char *name,
136                          uint16_t device_id, size_t config_size);
137 void virtio_cleanup(VirtIODevice *vdev);
138 
139 void virtio_error(VirtIODevice *vdev, const char *fmt, ...) GCC_FMT_ATTR(2, 3);
140 
141 /* Set the child bus name. */
142 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
143 
144 typedef void (*VirtIOHandleOutput)(VirtIODevice *, VirtQueue *);
145 
146 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
147                             VirtIOHandleOutput handle_output);
148 
149 VirtQueue *virtio_add_queue_aio(VirtIODevice *vdev, int queue_size,
150                                 VirtIOHandleOutput handle_output);
151 
152 void virtio_del_queue(VirtIODevice *vdev, int n);
153 
154 void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num);
155 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
156                     unsigned int len);
157 void virtqueue_flush(VirtQueue *vq, unsigned int count);
158 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
159                               unsigned int len);
160 void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem,
161                        unsigned int len);
162 bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
163 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
164                     unsigned int len, unsigned int idx);
165 
166 void virtqueue_map(VirtQueueElement *elem);
167 void *virtqueue_pop(VirtQueue *vq, size_t sz);
168 void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz);
169 void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem);
170 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
171                           unsigned int out_bytes);
172 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
173                                unsigned int *out_bytes,
174                                unsigned max_in_bytes, unsigned max_out_bytes);
175 
176 bool virtio_should_notify(VirtIODevice *vdev, VirtQueue *vq);
177 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
178 
179 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
180 void virtio_vmstate_save(QEMUFile *f, void *opaque, size_t size);
181 
182 extern const VMStateInfo virtio_vmstate_info;
183 
184 #ifdef VMSTATE_VIRTIO_DEVICE_USE_NEW
185 
186 #define VMSTATE_VIRTIO_DEVICE \
187     {                                         \
188         .name = "virtio",                     \
189         .info = &virtio_vmstate_info,         \
190         .flags = VMS_SINGLE,                  \
191     }
192 
193 #else
194 /* TODO remove conditional as soon as all users are converted */
195 
196 #define VMSTATE_VIRTIO_DEVICE(devname, v, getf, putf) \
197     static const VMStateDescription vmstate_virtio_ ## devname = { \
198         .name = "virtio-" #devname ,          \
199         .minimum_version_id = v,              \
200         .version_id = v,                      \
201         .fields = (VMStateField[]) {          \
202             {                                 \
203                 .name = "virtio",             \
204                 .info = &(const VMStateInfo) {\
205                         .name = "virtio",     \
206                         .get = getf,          \
207                         .put = putf,          \
208                     },                        \
209                 .flags = VMS_SINGLE,          \
210             },                                \
211             VMSTATE_END_OF_LIST()             \
212         }                                     \
213     }
214 
215 #endif
216 
217 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
218 
219 void virtio_notify_config(VirtIODevice *vdev);
220 
221 void virtio_queue_set_notification(VirtQueue *vq, int enable);
222 
223 int virtio_queue_ready(VirtQueue *vq);
224 
225 int virtio_queue_empty(VirtQueue *vq);
226 
227 /* Host binding interface.  */
228 
229 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
230 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
231 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
232 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
233 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
234 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
235 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
236 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
237 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
238 void virtio_config_modern_writeb(VirtIODevice *vdev,
239                                  uint32_t addr, uint32_t data);
240 void virtio_config_modern_writew(VirtIODevice *vdev,
241                                  uint32_t addr, uint32_t data);
242 void virtio_config_modern_writel(VirtIODevice *vdev,
243                                  uint32_t addr, uint32_t data);
244 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
245 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
246 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
247 int virtio_queue_get_num(VirtIODevice *vdev, int n);
248 int virtio_get_num_queues(VirtIODevice *vdev);
249 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
250                             hwaddr avail, hwaddr used);
251 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
252 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
253 void virtio_queue_notify(VirtIODevice *vdev, int n);
254 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
255 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
256 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
257 void virtio_reset(void *opaque);
258 void virtio_update_irq(VirtIODevice *vdev);
259 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
260 
261 /* Base devices.  */
262 typedef struct VirtIOBlkConf VirtIOBlkConf;
263 struct virtio_net_conf;
264 typedef struct virtio_serial_conf virtio_serial_conf;
265 typedef struct virtio_input_conf virtio_input_conf;
266 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
267 typedef struct VirtIORNGConf VirtIORNGConf;
268 
269 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
270     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
271                       VIRTIO_RING_F_INDIRECT_DESC, true), \
272     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
273                       VIRTIO_RING_F_EVENT_IDX, true),     \
274     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
275                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
276     DEFINE_PROP_BIT64("any_layout", _state, _field, \
277                       VIRTIO_F_ANY_LAYOUT, true)
278 
279 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
280 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
281 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
282 hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n);
283 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
284 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
285 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
286 hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n);
287 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
288 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
289 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
290 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
291 uint16_t virtio_get_queue_index(VirtQueue *vq);
292 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
293 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
294                                                 bool with_irqfd);
295 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
296 void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign,
297                                                bool set_handler);
298 void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
299                                                 void (*fn)(VirtIODevice *,
300                                                            VirtQueue *));
301 void virtio_irq(VirtQueue *vq);
302 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
303 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
304 
305 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
306 {
307     assert(fbit < 64);
308     *features |= (1ULL << fbit);
309 }
310 
311 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
312 {
313     assert(fbit < 64);
314     *features &= ~(1ULL << fbit);
315 }
316 
317 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
318 {
319     assert(fbit < 64);
320     return !!(features & (1ULL << fbit));
321 }
322 
323 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
324                                            unsigned int fbit)
325 {
326     return virtio_has_feature(vdev->guest_features, fbit);
327 }
328 
329 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
330                                            unsigned int fbit)
331 {
332     return virtio_has_feature(vdev->host_features, fbit);
333 }
334 
335 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
336 {
337     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
338         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
339         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
340     }
341     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
342     return false;
343 }
344 #endif
345