xref: /openbmc/qemu/include/hw/virtio/virtio.h (revision 8692aa29)
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     VMChangeStateEntry *vmstate;
91     char *bus_name;
92     uint8_t device_endian;
93     bool use_guest_notifier_mask;
94     QLIST_HEAD(, VirtQueue) *vector_queues;
95 };
96 
97 typedef struct VirtioDeviceClass {
98     /*< private >*/
99     DeviceClass parent;
100     /*< public >*/
101 
102     /* This is what a VirtioDevice must implement */
103     DeviceRealize realize;
104     DeviceUnrealize unrealize;
105     uint64_t (*get_features)(VirtIODevice *vdev,
106                              uint64_t requested_features,
107                              Error **errp);
108     uint64_t (*bad_features)(VirtIODevice *vdev);
109     void (*set_features)(VirtIODevice *vdev, uint64_t val);
110     int (*validate_features)(VirtIODevice *vdev);
111     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
112     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
113     void (*reset)(VirtIODevice *vdev);
114     void (*set_status)(VirtIODevice *vdev, uint8_t val);
115     /* Test and clear event pending status.
116      * Should be called after unmask to avoid losing events.
117      * If backend does not support masking,
118      * must check in frontend instead.
119      */
120     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
121     /* Mask/unmask events from this vq. Any events reported
122      * while masked will become pending.
123      * If backend does not support masking,
124      * must mask in frontend instead.
125      */
126     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
127     void (*save)(VirtIODevice *vdev, QEMUFile *f);
128     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
129 } VirtioDeviceClass;
130 
131 void virtio_instance_init_common(Object *proxy_obj, void *data,
132                                  size_t vdev_size, const char *vdev_name);
133 
134 void virtio_init(VirtIODevice *vdev, const char *name,
135                          uint16_t device_id, size_t config_size);
136 void virtio_cleanup(VirtIODevice *vdev);
137 
138 /* Set the child bus name. */
139 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
140 
141 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
142                             void (*handle_output)(VirtIODevice *,
143                                                   VirtQueue *));
144 
145 void virtio_del_queue(VirtIODevice *vdev, int n);
146 
147 void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num);
148 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
149                     unsigned int len);
150 void virtqueue_flush(VirtQueue *vq, unsigned int count);
151 void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem,
152                        unsigned int len);
153 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
154                     unsigned int len, unsigned int idx);
155 
156 void virtqueue_map(VirtQueueElement *elem);
157 void *virtqueue_pop(VirtQueue *vq, size_t sz);
158 void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz);
159 void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem);
160 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
161                           unsigned int out_bytes);
162 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
163                                unsigned int *out_bytes,
164                                unsigned max_in_bytes, unsigned max_out_bytes);
165 
166 bool virtio_should_notify(VirtIODevice *vdev, VirtQueue *vq);
167 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
168 
169 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
170 
171 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
172 
173 void virtio_notify_config(VirtIODevice *vdev);
174 
175 void virtio_queue_set_notification(VirtQueue *vq, int enable);
176 
177 int virtio_queue_ready(VirtQueue *vq);
178 
179 int virtio_queue_empty(VirtQueue *vq);
180 
181 /* Host binding interface.  */
182 
183 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
184 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
185 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
186 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
187 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
188 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
189 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
190 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
191 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
192 void virtio_config_modern_writeb(VirtIODevice *vdev,
193                                  uint32_t addr, uint32_t data);
194 void virtio_config_modern_writew(VirtIODevice *vdev,
195                                  uint32_t addr, uint32_t data);
196 void virtio_config_modern_writel(VirtIODevice *vdev,
197                                  uint32_t addr, uint32_t data);
198 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
199 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
200 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
201 int virtio_queue_get_num(VirtIODevice *vdev, int n);
202 int virtio_get_num_queues(VirtIODevice *vdev);
203 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
204                             hwaddr avail, hwaddr used);
205 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
206 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
207 void virtio_queue_notify(VirtIODevice *vdev, int n);
208 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
209 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
210 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
211 void virtio_reset(void *opaque);
212 void virtio_update_irq(VirtIODevice *vdev);
213 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
214 
215 /* Base devices.  */
216 typedef struct VirtIOBlkConf VirtIOBlkConf;
217 struct virtio_net_conf;
218 typedef struct virtio_serial_conf virtio_serial_conf;
219 typedef struct virtio_input_conf virtio_input_conf;
220 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
221 typedef struct VirtIORNGConf VirtIORNGConf;
222 
223 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
224     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
225                       VIRTIO_RING_F_INDIRECT_DESC, true), \
226     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
227                       VIRTIO_RING_F_EVENT_IDX, true),     \
228     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
229                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
230     DEFINE_PROP_BIT64("any_layout", _state, _field, \
231                       VIRTIO_F_ANY_LAYOUT, true)
232 
233 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
234 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
235 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
236 hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n);
237 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
238 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
239 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
240 hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n);
241 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
242 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
243 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
244 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
245 uint16_t virtio_get_queue_index(VirtQueue *vq);
246 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
247 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
248                                                 bool with_irqfd);
249 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
250 void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign,
251                                                bool set_handler);
252 void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
253                                                 void (*fn)(VirtIODevice *,
254                                                            VirtQueue *));
255 void virtio_irq(VirtQueue *vq);
256 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
257 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
258 
259 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
260 {
261     assert(fbit < 64);
262     *features |= (1ULL << fbit);
263 }
264 
265 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
266 {
267     assert(fbit < 64);
268     *features &= ~(1ULL << fbit);
269 }
270 
271 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
272 {
273     assert(fbit < 64);
274     return !!(features & (1ULL << fbit));
275 }
276 
277 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
278                                            unsigned int fbit)
279 {
280     return virtio_has_feature(vdev->guest_features, fbit);
281 }
282 
283 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
284                                            unsigned int fbit)
285 {
286     return virtio_has_feature(vdev->host_features, fbit);
287 }
288 
289 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
290 {
291     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
292         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
293         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
294     }
295     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
296     return false;
297 }
298 #endif
299