xref: /openbmc/qemu/include/hw/virtio/virtio.h (revision a68694cd)
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 "exec/memory.h"
18 #include "hw/qdev-core.h"
19 #include "net/net.h"
20 #include "migration/vmstate.h"
21 #include "qemu/event_notifier.h"
22 #include "standard-headers/linux/virtio_config.h"
23 #include "standard-headers/linux/virtio_ring.h"
24 #include "qom/object.h"
25 
26 /* A guest should never accept this.  It implies negotiation is broken. */
27 #define VIRTIO_F_BAD_FEATURE		30
28 
29 #define VIRTIO_LEGACY_FEATURES ((0x1ULL << VIRTIO_F_BAD_FEATURE) | \
30                                 (0x1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) | \
31                                 (0x1ULL << VIRTIO_F_ANY_LAYOUT))
32 
33 struct VirtQueue;
34 
35 static inline hwaddr vring_align(hwaddr addr,
36                                              unsigned long align)
37 {
38     return QEMU_ALIGN_UP(addr, align);
39 }
40 
41 typedef struct VirtIOFeature {
42     uint64_t flags;
43     size_t end;
44 } VirtIOFeature;
45 
46 size_t virtio_feature_get_config_size(VirtIOFeature *features,
47                                       uint64_t host_features);
48 
49 typedef struct VirtQueue VirtQueue;
50 
51 #define VIRTQUEUE_MAX_SIZE 1024
52 
53 typedef struct VirtQueueElement
54 {
55     unsigned int index;
56     unsigned int len;
57     unsigned int ndescs;
58     unsigned int out_num;
59     unsigned int in_num;
60     hwaddr *in_addr;
61     hwaddr *out_addr;
62     struct iovec *in_sg;
63     struct iovec *out_sg;
64 } VirtQueueElement;
65 
66 #define VIRTIO_QUEUE_MAX 1024
67 
68 #define VIRTIO_NO_VECTOR 0xffff
69 
70 #define TYPE_VIRTIO_DEVICE "virtio-device"
71 typedef struct VirtioDeviceClass VirtioDeviceClass;
72 DECLARE_OBJ_CHECKERS(VirtIODevice, VirtioDeviceClass,
73                      VIRTIO_DEVICE, TYPE_VIRTIO_DEVICE)
74 
75 enum virtio_device_endian {
76     VIRTIO_DEVICE_ENDIAN_UNKNOWN,
77     VIRTIO_DEVICE_ENDIAN_LITTLE,
78     VIRTIO_DEVICE_ENDIAN_BIG,
79 };
80 
81 struct VirtIODevice
82 {
83     DeviceState parent_obj;
84     const char *name;
85     uint8_t status;
86     uint8_t isr;
87     uint16_t queue_sel;
88     uint64_t guest_features;
89     uint64_t host_features;
90     uint64_t backend_features;
91     size_t config_len;
92     void *config;
93     uint16_t config_vector;
94     uint32_t generation;
95     int nvectors;
96     VirtQueue *vq;
97     MemoryListener listener;
98     uint16_t device_id;
99     bool vm_running;
100     bool broken; /* device in invalid state, needs reset */
101     bool use_disabled_flag; /* allow use of 'disable' flag when needed */
102     bool disabled; /* device in temporarily disabled state */
103     bool use_started;
104     bool started;
105     bool start_on_kick; /* when virtio 1.0 feature has not been negotiated */
106     VMChangeStateEntry *vmstate;
107     char *bus_name;
108     uint8_t device_endian;
109     bool use_guest_notifier_mask;
110     AddressSpace *dma_as;
111     QLIST_HEAD(, VirtQueue) *vector_queues;
112 };
113 
114 struct VirtioDeviceClass {
115     /*< private >*/
116     DeviceClass parent;
117     /*< public >*/
118 
119     /* This is what a VirtioDevice must implement */
120     DeviceRealize realize;
121     DeviceUnrealize unrealize;
122     uint64_t (*get_features)(VirtIODevice *vdev,
123                              uint64_t requested_features,
124                              Error **errp);
125     uint64_t (*bad_features)(VirtIODevice *vdev);
126     void (*set_features)(VirtIODevice *vdev, uint64_t val);
127     int (*validate_features)(VirtIODevice *vdev);
128     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
129     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
130     void (*reset)(VirtIODevice *vdev);
131     void (*set_status)(VirtIODevice *vdev, uint8_t val);
132     /* For transitional devices, this is a bitmap of features
133      * that are only exposed on the legacy interface but not
134      * the modern one.
135      */
136     uint64_t legacy_features;
137     /* Test and clear event pending status.
138      * Should be called after unmask to avoid losing events.
139      * If backend does not support masking,
140      * must check in frontend instead.
141      */
142     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
143     /* Mask/unmask events from this vq. Any events reported
144      * while masked will become pending.
145      * If backend does not support masking,
146      * must mask in frontend instead.
147      */
148     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
149     int (*start_ioeventfd)(VirtIODevice *vdev);
150     void (*stop_ioeventfd)(VirtIODevice *vdev);
151     /* Saving and loading of a device; trying to deprecate save/load
152      * use vmsd for new devices.
153      */
154     void (*save)(VirtIODevice *vdev, QEMUFile *f);
155     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
156     /* Post load hook in vmsd is called early while device is processed, and
157      * when VirtIODevice isn't fully initialized.  Devices should use this instead,
158      * unless they specifically want to verify the migration stream as it's
159      * processed, e.g. for bounds checking.
160      */
161     int (*post_load)(VirtIODevice *vdev);
162     const VMStateDescription *vmsd;
163     bool (*primary_unplug_pending)(void *opaque);
164 };
165 
166 void virtio_instance_init_common(Object *proxy_obj, void *data,
167                                  size_t vdev_size, const char *vdev_name);
168 
169 void virtio_init(VirtIODevice *vdev, const char *name,
170                          uint16_t device_id, size_t config_size);
171 void virtio_cleanup(VirtIODevice *vdev);
172 
173 void virtio_error(VirtIODevice *vdev, const char *fmt, ...) GCC_FMT_ATTR(2, 3);
174 
175 /* Set the child bus name. */
176 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
177 
178 typedef void (*VirtIOHandleOutput)(VirtIODevice *, VirtQueue *);
179 typedef bool (*VirtIOHandleAIOOutput)(VirtIODevice *, VirtQueue *);
180 
181 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
182                             VirtIOHandleOutput handle_output);
183 
184 void virtio_del_queue(VirtIODevice *vdev, int n);
185 
186 void virtio_delete_queue(VirtQueue *vq);
187 
188 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
189                     unsigned int len);
190 void virtqueue_flush(VirtQueue *vq, unsigned int count);
191 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
192                               unsigned int len);
193 void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem,
194                      unsigned int len);
195 bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
196 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
197                     unsigned int len, unsigned int idx);
198 
199 void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem);
200 void *virtqueue_pop(VirtQueue *vq, size_t sz);
201 unsigned int virtqueue_drop_all(VirtQueue *vq);
202 void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz);
203 void qemu_put_virtqueue_element(VirtIODevice *vdev, QEMUFile *f,
204                                 VirtQueueElement *elem);
205 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
206                           unsigned int out_bytes);
207 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
208                                unsigned int *out_bytes,
209                                unsigned max_in_bytes, unsigned max_out_bytes);
210 
211 void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq);
212 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
213 
214 int virtio_save(VirtIODevice *vdev, QEMUFile *f);
215 
216 extern const VMStateInfo virtio_vmstate_info;
217 
218 #define VMSTATE_VIRTIO_DEVICE \
219     {                                         \
220         .name = "virtio",                     \
221         .info = &virtio_vmstate_info,         \
222         .flags = VMS_SINGLE,                  \
223     }
224 
225 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
226 
227 void virtio_notify_config(VirtIODevice *vdev);
228 
229 bool virtio_queue_get_notification(VirtQueue *vq);
230 void virtio_queue_set_notification(VirtQueue *vq, int enable);
231 
232 int virtio_queue_ready(VirtQueue *vq);
233 
234 int virtio_queue_empty(VirtQueue *vq);
235 
236 /* Host binding interface.  */
237 
238 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
239 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
240 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
241 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
242 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
243 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
244 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
245 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
246 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
247 void virtio_config_modern_writeb(VirtIODevice *vdev,
248                                  uint32_t addr, uint32_t data);
249 void virtio_config_modern_writew(VirtIODevice *vdev,
250                                  uint32_t addr, uint32_t data);
251 void virtio_config_modern_writel(VirtIODevice *vdev,
252                                  uint32_t addr, uint32_t data);
253 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
254 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
255 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
256 int virtio_queue_get_num(VirtIODevice *vdev, int n);
257 int virtio_queue_get_max_num(VirtIODevice *vdev, int n);
258 int virtio_get_num_queues(VirtIODevice *vdev);
259 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
260                             hwaddr avail, hwaddr used);
261 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
262 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
263 void virtio_queue_notify(VirtIODevice *vdev, int n);
264 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
265 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
266 int virtio_queue_set_host_notifier_mr(VirtIODevice *vdev, int n,
267                                       MemoryRegion *mr, bool assign);
268 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
269 void virtio_reset(void *opaque);
270 void virtio_update_irq(VirtIODevice *vdev);
271 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
272 
273 /* Base devices.  */
274 typedef struct VirtIOBlkConf VirtIOBlkConf;
275 struct virtio_net_conf;
276 typedef struct virtio_serial_conf virtio_serial_conf;
277 typedef struct virtio_input_conf virtio_input_conf;
278 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
279 typedef struct VirtIORNGConf VirtIORNGConf;
280 
281 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
282     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
283                       VIRTIO_RING_F_INDIRECT_DESC, true), \
284     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
285                       VIRTIO_RING_F_EVENT_IDX, true),     \
286     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
287                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
288     DEFINE_PROP_BIT64("any_layout", _state, _field, \
289                       VIRTIO_F_ANY_LAYOUT, true), \
290     DEFINE_PROP_BIT64("iommu_platform", _state, _field, \
291                       VIRTIO_F_IOMMU_PLATFORM, false), \
292     DEFINE_PROP_BIT64("packed", _state, _field, \
293                       VIRTIO_F_RING_PACKED, false)
294 
295 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
296 bool virtio_queue_enabled_legacy(VirtIODevice *vdev, int n);
297 bool virtio_queue_enabled(VirtIODevice *vdev, int n);
298 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
299 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
300 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
301 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
302 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
303 unsigned int virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
304 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n,
305                                      unsigned int idx);
306 void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n);
307 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
308 void virtio_queue_update_used_idx(VirtIODevice *vdev, int n);
309 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
310 uint16_t virtio_get_queue_index(VirtQueue *vq);
311 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
312 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
313                                                 bool with_irqfd);
314 int virtio_device_start_ioeventfd(VirtIODevice *vdev);
315 int virtio_device_grab_ioeventfd(VirtIODevice *vdev);
316 void virtio_device_release_ioeventfd(VirtIODevice *vdev);
317 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev);
318 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
319 void virtio_queue_set_host_notifier_enabled(VirtQueue *vq, bool enabled);
320 void virtio_queue_host_notifier_read(EventNotifier *n);
321 void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
322                                                 VirtIOHandleAIOOutput handle_output);
323 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
324 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
325 
326 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
327 {
328     assert(fbit < 64);
329     *features |= (1ULL << fbit);
330 }
331 
332 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
333 {
334     assert(fbit < 64);
335     *features &= ~(1ULL << fbit);
336 }
337 
338 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
339 {
340     assert(fbit < 64);
341     return !!(features & (1ULL << fbit));
342 }
343 
344 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
345                                            unsigned int fbit)
346 {
347     return virtio_has_feature(vdev->guest_features, fbit);
348 }
349 
350 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
351                                            unsigned int fbit)
352 {
353     return virtio_has_feature(vdev->host_features, fbit);
354 }
355 
356 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
357 {
358     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
359         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
360         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
361     }
362     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
363     return false;
364 }
365 
366 static inline bool virtio_device_started(VirtIODevice *vdev, uint8_t status)
367 {
368     if (vdev->use_started) {
369         return vdev->started;
370     }
371 
372     return status & VIRTIO_CONFIG_S_DRIVER_OK;
373 }
374 
375 static inline void virtio_set_started(VirtIODevice *vdev, bool started)
376 {
377     if (started) {
378         vdev->start_on_kick = false;
379     }
380 
381     if (vdev->use_started) {
382         vdev->started = started;
383     }
384 }
385 
386 static inline void virtio_set_disabled(VirtIODevice *vdev, bool disable)
387 {
388     if (vdev->use_disabled_flag) {
389         vdev->disabled = disable;
390     }
391 }
392 
393 static inline bool virtio_device_disabled(VirtIODevice *vdev)
394 {
395     return unlikely(vdev->disabled || vdev->broken);
396 }
397 
398 bool virtio_legacy_allowed(VirtIODevice *vdev);
399 
400 #endif
401