xref: /qemu/include/hw/virtio/virtio.h (revision bf91bd27924955aa243abfa5d422ee71e9e84b93)
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     int (*start_ioeventfd)(VirtIODevice *vdev);
129     void (*stop_ioeventfd)(VirtIODevice *vdev);
130     /* Saving and loading of a device; trying to deprecate save/load
131      * use vmsd for new devices.
132      */
133     void (*save)(VirtIODevice *vdev, QEMUFile *f);
134     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
135     const VMStateDescription *vmsd;
136 } VirtioDeviceClass;
137 
138 void virtio_instance_init_common(Object *proxy_obj, void *data,
139                                  size_t vdev_size, const char *vdev_name);
140 
141 void virtio_init(VirtIODevice *vdev, const char *name,
142                          uint16_t device_id, size_t config_size);
143 void virtio_cleanup(VirtIODevice *vdev);
144 
145 void virtio_error(VirtIODevice *vdev, const char *fmt, ...) GCC_FMT_ATTR(2, 3);
146 
147 /* Set the child bus name. */
148 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
149 
150 typedef void (*VirtIOHandleOutput)(VirtIODevice *, VirtQueue *);
151 
152 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
153                             VirtIOHandleOutput handle_output);
154 
155 void virtio_del_queue(VirtIODevice *vdev, int n);
156 
157 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
158                     unsigned int len);
159 void virtqueue_flush(VirtQueue *vq, unsigned int count);
160 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
161                               unsigned int len);
162 void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem,
163                      unsigned int len);
164 bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
165 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
166                     unsigned int len, unsigned int idx);
167 
168 void virtqueue_map(VirtQueueElement *elem);
169 void *virtqueue_pop(VirtQueue *vq, size_t sz);
170 void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz);
171 void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem);
172 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
173                           unsigned int out_bytes);
174 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
175                                unsigned int *out_bytes,
176                                unsigned max_in_bytes, unsigned max_out_bytes);
177 
178 bool virtio_should_notify(VirtIODevice *vdev, VirtQueue *vq);
179 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
180 
181 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
182 
183 extern const VMStateInfo virtio_vmstate_info;
184 
185 #define VMSTATE_VIRTIO_DEVICE \
186     {                                         \
187         .name = "virtio",                     \
188         .info = &virtio_vmstate_info,         \
189         .flags = VMS_SINGLE,                  \
190     }
191 
192 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
193 
194 void virtio_notify_config(VirtIODevice *vdev);
195 
196 void virtio_queue_set_notification(VirtQueue *vq, int enable);
197 
198 int virtio_queue_ready(VirtQueue *vq);
199 
200 int virtio_queue_empty(VirtQueue *vq);
201 
202 /* Host binding interface.  */
203 
204 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
205 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
206 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
207 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
208 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
209 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
210 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
211 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
212 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
213 void virtio_config_modern_writeb(VirtIODevice *vdev,
214                                  uint32_t addr, uint32_t data);
215 void virtio_config_modern_writew(VirtIODevice *vdev,
216                                  uint32_t addr, uint32_t data);
217 void virtio_config_modern_writel(VirtIODevice *vdev,
218                                  uint32_t addr, uint32_t data);
219 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
220 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
221 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
222 int virtio_queue_get_num(VirtIODevice *vdev, int n);
223 int virtio_get_num_queues(VirtIODevice *vdev);
224 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
225                             hwaddr avail, hwaddr used);
226 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
227 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
228 void virtio_queue_notify(VirtIODevice *vdev, int n);
229 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
230 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
231 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
232 void virtio_reset(void *opaque);
233 void virtio_update_irq(VirtIODevice *vdev);
234 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
235 
236 /* Base devices.  */
237 typedef struct VirtIOBlkConf VirtIOBlkConf;
238 struct virtio_net_conf;
239 typedef struct virtio_serial_conf virtio_serial_conf;
240 typedef struct virtio_input_conf virtio_input_conf;
241 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
242 typedef struct VirtIORNGConf VirtIORNGConf;
243 
244 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
245     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
246                       VIRTIO_RING_F_INDIRECT_DESC, true), \
247     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
248                       VIRTIO_RING_F_EVENT_IDX, true),     \
249     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
250                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
251     DEFINE_PROP_BIT64("any_layout", _state, _field, \
252                       VIRTIO_F_ANY_LAYOUT, true)
253 
254 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
255 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
256 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
257 hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n);
258 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
259 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
260 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
261 hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n);
262 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
263 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
264 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
265 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
266 uint16_t virtio_get_queue_index(VirtQueue *vq);
267 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
268 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
269                                                 bool with_irqfd);
270 int virtio_device_start_ioeventfd(VirtIODevice *vdev);
271 void virtio_device_stop_ioeventfd(VirtIODevice *vdev);
272 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev);
273 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
274 void virtio_queue_host_notifier_read(EventNotifier *n);
275 void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
276                                                 void (*fn)(VirtIODevice *,
277                                                            VirtQueue *));
278 void virtio_irq(VirtQueue *vq);
279 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
280 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
281 
282 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
283 {
284     assert(fbit < 64);
285     *features |= (1ULL << fbit);
286 }
287 
288 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
289 {
290     assert(fbit < 64);
291     *features &= ~(1ULL << fbit);
292 }
293 
294 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
295 {
296     assert(fbit < 64);
297     return !!(features & (1ULL << fbit));
298 }
299 
300 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
301                                            unsigned int fbit)
302 {
303     return virtio_has_feature(vdev->guest_features, fbit);
304 }
305 
306 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
307                                            unsigned int fbit)
308 {
309     return virtio_has_feature(vdev->host_features, fbit);
310 }
311 
312 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
313 {
314     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
315         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
316         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
317     }
318     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
319     return false;
320 }
321 #endif
322