xref: /openbmc/qemu/include/hw/virtio/virtio.h (revision 55bbc861)
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 QEMU_ALIGN_UP(addr, align);
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     uint64_t backend_features;
83     size_t config_len;
84     void *config;
85     uint16_t config_vector;
86     uint32_t generation;
87     int nvectors;
88     VirtQueue *vq;
89     MemoryListener listener;
90     uint16_t device_id;
91     bool vm_running;
92     bool broken; /* device in invalid state, needs reset */
93     VMChangeStateEntry *vmstate;
94     char *bus_name;
95     uint8_t device_endian;
96     bool use_guest_notifier_mask;
97     AddressSpace *dma_as;
98     QLIST_HEAD(, VirtQueue) *vector_queues;
99 };
100 
101 typedef struct VirtioDeviceClass {
102     /*< private >*/
103     DeviceClass parent;
104     /*< public >*/
105 
106     /* This is what a VirtioDevice must implement */
107     DeviceRealize realize;
108     DeviceUnrealize unrealize;
109     uint64_t (*get_features)(VirtIODevice *vdev,
110                              uint64_t requested_features,
111                              Error **errp);
112     uint64_t (*bad_features)(VirtIODevice *vdev);
113     void (*set_features)(VirtIODevice *vdev, uint64_t val);
114     int (*validate_features)(VirtIODevice *vdev);
115     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
116     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
117     void (*reset)(VirtIODevice *vdev);
118     void (*set_status)(VirtIODevice *vdev, uint8_t val);
119     /* For transitional devices, this is a bitmap of features
120      * that are only exposed on the legacy interface but not
121      * the modern one.
122      */
123     uint64_t legacy_features;
124     /* Test and clear event pending status.
125      * Should be called after unmask to avoid losing events.
126      * If backend does not support masking,
127      * must check in frontend instead.
128      */
129     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
130     /* Mask/unmask events from this vq. Any events reported
131      * while masked will become pending.
132      * If backend does not support masking,
133      * must mask in frontend instead.
134      */
135     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
136     int (*start_ioeventfd)(VirtIODevice *vdev);
137     void (*stop_ioeventfd)(VirtIODevice *vdev);
138     /* Saving and loading of a device; trying to deprecate save/load
139      * use vmsd for new devices.
140      */
141     void (*save)(VirtIODevice *vdev, QEMUFile *f);
142     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
143     const VMStateDescription *vmsd;
144 } VirtioDeviceClass;
145 
146 void virtio_instance_init_common(Object *proxy_obj, void *data,
147                                  size_t vdev_size, const char *vdev_name);
148 
149 void virtio_init(VirtIODevice *vdev, const char *name,
150                          uint16_t device_id, size_t config_size);
151 void virtio_cleanup(VirtIODevice *vdev);
152 
153 void virtio_error(VirtIODevice *vdev, const char *fmt, ...) GCC_FMT_ATTR(2, 3);
154 
155 /* Set the child bus name. */
156 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
157 
158 typedef void (*VirtIOHandleOutput)(VirtIODevice *, VirtQueue *);
159 typedef bool (*VirtIOHandleAIOOutput)(VirtIODevice *, VirtQueue *);
160 
161 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
162                             VirtIOHandleOutput handle_output);
163 
164 void virtio_del_queue(VirtIODevice *vdev, int n);
165 
166 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
167                     unsigned int len);
168 void virtqueue_flush(VirtQueue *vq, unsigned int count);
169 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
170                               unsigned int len);
171 void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem,
172                      unsigned int len);
173 bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
174 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
175                     unsigned int len, unsigned int idx);
176 
177 void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem);
178 void *virtqueue_pop(VirtQueue *vq, size_t sz);
179 unsigned int virtqueue_drop_all(VirtQueue *vq);
180 void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz);
181 void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem);
182 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
183                           unsigned int out_bytes);
184 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
185                                unsigned int *out_bytes,
186                                unsigned max_in_bytes, unsigned max_out_bytes);
187 
188 void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq);
189 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
190 
191 int virtio_save(VirtIODevice *vdev, QEMUFile *f);
192 
193 extern const VMStateInfo virtio_vmstate_info;
194 
195 #define VMSTATE_VIRTIO_DEVICE \
196     {                                         \
197         .name = "virtio",                     \
198         .info = &virtio_vmstate_info,         \
199         .flags = VMS_SINGLE,                  \
200     }
201 
202 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
203 
204 void virtio_notify_config(VirtIODevice *vdev);
205 
206 void virtio_queue_set_notification(VirtQueue *vq, int enable);
207 
208 int virtio_queue_ready(VirtQueue *vq);
209 
210 int virtio_queue_empty(VirtQueue *vq);
211 
212 /* Host binding interface.  */
213 
214 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
215 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
216 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
217 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
218 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
219 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
220 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
221 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
222 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
223 void virtio_config_modern_writeb(VirtIODevice *vdev,
224                                  uint32_t addr, uint32_t data);
225 void virtio_config_modern_writew(VirtIODevice *vdev,
226                                  uint32_t addr, uint32_t data);
227 void virtio_config_modern_writel(VirtIODevice *vdev,
228                                  uint32_t addr, uint32_t data);
229 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
230 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
231 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
232 int virtio_queue_get_num(VirtIODevice *vdev, int n);
233 int virtio_queue_get_max_num(VirtIODevice *vdev, int n);
234 int virtio_get_num_queues(VirtIODevice *vdev);
235 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
236                             hwaddr avail, hwaddr used);
237 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
238 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
239 void virtio_queue_notify(VirtIODevice *vdev, int n);
240 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
241 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
242 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
243 void virtio_reset(void *opaque);
244 void virtio_update_irq(VirtIODevice *vdev);
245 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
246 
247 /* Base devices.  */
248 typedef struct VirtIOBlkConf VirtIOBlkConf;
249 struct virtio_net_conf;
250 typedef struct virtio_serial_conf virtio_serial_conf;
251 typedef struct virtio_input_conf virtio_input_conf;
252 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
253 typedef struct VirtIORNGConf VirtIORNGConf;
254 
255 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
256     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
257                       VIRTIO_RING_F_INDIRECT_DESC, true), \
258     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
259                       VIRTIO_RING_F_EVENT_IDX, true),     \
260     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
261                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
262     DEFINE_PROP_BIT64("any_layout", _state, _field, \
263                       VIRTIO_F_ANY_LAYOUT, true), \
264     DEFINE_PROP_BIT64("iommu_platform", _state, _field, \
265                       VIRTIO_F_IOMMU_PLATFORM, false)
266 
267 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
268 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
269 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
270 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
271 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
272 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
273 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
274 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
275 void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n);
276 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
277 void virtio_queue_update_used_idx(VirtIODevice *vdev, int n);
278 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
279 uint16_t virtio_get_queue_index(VirtQueue *vq);
280 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
281 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
282                                                 bool with_irqfd);
283 int virtio_device_start_ioeventfd(VirtIODevice *vdev);
284 void virtio_device_stop_ioeventfd(VirtIODevice *vdev);
285 int virtio_device_grab_ioeventfd(VirtIODevice *vdev);
286 void virtio_device_release_ioeventfd(VirtIODevice *vdev);
287 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev);
288 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
289 void virtio_queue_host_notifier_read(EventNotifier *n);
290 void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
291                                                 VirtIOHandleAIOOutput handle_output);
292 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
293 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
294 
295 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
296 {
297     assert(fbit < 64);
298     *features |= (1ULL << fbit);
299 }
300 
301 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
302 {
303     assert(fbit < 64);
304     *features &= ~(1ULL << fbit);
305 }
306 
307 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
308 {
309     assert(fbit < 64);
310     return !!(features & (1ULL << fbit));
311 }
312 
313 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
314                                            unsigned int fbit)
315 {
316     return virtio_has_feature(vdev->guest_features, fbit);
317 }
318 
319 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
320                                            unsigned int fbit)
321 {
322     return virtio_has_feature(vdev->host_features, fbit);
323 }
324 
325 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
326 {
327     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
328         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
329         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
330     }
331     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
332     return false;
333 }
334 #endif
335