xref: /openbmc/qemu/include/hw/virtio/virtio.h (revision c2b38b27)
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     MemoryListener listener;
89     uint16_t device_id;
90     bool vm_running;
91     bool broken; /* device in invalid state, needs reset */
92     VMChangeStateEntry *vmstate;
93     char *bus_name;
94     uint8_t device_endian;
95     bool use_guest_notifier_mask;
96     AddressSpace *dma_as;
97     QLIST_HEAD(, VirtQueue) *vector_queues;
98 };
99 
100 typedef struct VirtioDeviceClass {
101     /*< private >*/
102     DeviceClass parent;
103     /*< public >*/
104 
105     /* This is what a VirtioDevice must implement */
106     DeviceRealize realize;
107     DeviceUnrealize unrealize;
108     uint64_t (*get_features)(VirtIODevice *vdev,
109                              uint64_t requested_features,
110                              Error **errp);
111     uint64_t (*bad_features)(VirtIODevice *vdev);
112     void (*set_features)(VirtIODevice *vdev, uint64_t val);
113     int (*validate_features)(VirtIODevice *vdev);
114     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
115     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
116     void (*reset)(VirtIODevice *vdev);
117     void (*set_status)(VirtIODevice *vdev, uint8_t val);
118     /* For transitional devices, this is a bitmap of features
119      * that are only exposed on the legacy interface but not
120      * the modern one.
121      */
122     uint64_t legacy_features;
123     /* Test and clear event pending status.
124      * Should be called after unmask to avoid losing events.
125      * If backend does not support masking,
126      * must check in frontend instead.
127      */
128     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
129     /* Mask/unmask events from this vq. Any events reported
130      * while masked will become pending.
131      * If backend does not support masking,
132      * must mask in frontend instead.
133      */
134     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
135     int (*start_ioeventfd)(VirtIODevice *vdev);
136     void (*stop_ioeventfd)(VirtIODevice *vdev);
137     /* Saving and loading of a device; trying to deprecate save/load
138      * use vmsd for new devices.
139      */
140     void (*save)(VirtIODevice *vdev, QEMUFile *f);
141     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
142     const VMStateDescription *vmsd;
143 } VirtioDeviceClass;
144 
145 void virtio_instance_init_common(Object *proxy_obj, void *data,
146                                  size_t vdev_size, const char *vdev_name);
147 
148 void virtio_init(VirtIODevice *vdev, const char *name,
149                          uint16_t device_id, size_t config_size);
150 void virtio_cleanup(VirtIODevice *vdev);
151 
152 void virtio_error(VirtIODevice *vdev, const char *fmt, ...) GCC_FMT_ATTR(2, 3);
153 
154 /* Set the child bus name. */
155 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
156 
157 typedef void (*VirtIOHandleOutput)(VirtIODevice *, VirtQueue *);
158 typedef bool (*VirtIOHandleAIOOutput)(VirtIODevice *, VirtQueue *);
159 
160 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
161                             VirtIOHandleOutput handle_output);
162 
163 void virtio_del_queue(VirtIODevice *vdev, int n);
164 
165 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
166                     unsigned int len);
167 void virtqueue_flush(VirtQueue *vq, unsigned int count);
168 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
169                               unsigned int len);
170 void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem,
171                      unsigned int len);
172 bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
173 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
174                     unsigned int len, unsigned int idx);
175 
176 void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem);
177 void *virtqueue_pop(VirtQueue *vq, size_t sz);
178 unsigned int virtqueue_drop_all(VirtQueue *vq);
179 void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz);
180 void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem);
181 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
182                           unsigned int out_bytes);
183 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
184                                unsigned int *out_bytes,
185                                unsigned max_in_bytes, unsigned max_out_bytes);
186 
187 void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq);
188 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
189 
190 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
191 
192 extern const VMStateInfo virtio_vmstate_info;
193 
194 #define VMSTATE_VIRTIO_DEVICE \
195     {                                         \
196         .name = "virtio",                     \
197         .info = &virtio_vmstate_info,         \
198         .flags = VMS_SINGLE,                  \
199     }
200 
201 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
202 
203 void virtio_notify_config(VirtIODevice *vdev);
204 
205 void virtio_queue_set_notification(VirtQueue *vq, int enable);
206 
207 int virtio_queue_ready(VirtQueue *vq);
208 
209 int virtio_queue_empty(VirtQueue *vq);
210 
211 /* Host binding interface.  */
212 
213 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
214 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
215 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
216 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
217 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
218 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
219 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
220 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
221 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
222 void virtio_config_modern_writeb(VirtIODevice *vdev,
223                                  uint32_t addr, uint32_t data);
224 void virtio_config_modern_writew(VirtIODevice *vdev,
225                                  uint32_t addr, uint32_t data);
226 void virtio_config_modern_writel(VirtIODevice *vdev,
227                                  uint32_t addr, uint32_t data);
228 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
229 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
230 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
231 int virtio_queue_get_num(VirtIODevice *vdev, int n);
232 int virtio_queue_get_max_num(VirtIODevice *vdev, int n);
233 int virtio_get_num_queues(VirtIODevice *vdev);
234 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
235                             hwaddr avail, hwaddr used);
236 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
237 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
238 void virtio_queue_notify(VirtIODevice *vdev, int n);
239 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
240 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
241 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
242 void virtio_reset(void *opaque);
243 void virtio_update_irq(VirtIODevice *vdev);
244 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
245 
246 /* Base devices.  */
247 typedef struct VirtIOBlkConf VirtIOBlkConf;
248 struct virtio_net_conf;
249 typedef struct virtio_serial_conf virtio_serial_conf;
250 typedef struct virtio_input_conf virtio_input_conf;
251 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
252 typedef struct VirtIORNGConf VirtIORNGConf;
253 
254 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
255     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
256                       VIRTIO_RING_F_INDIRECT_DESC, true), \
257     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
258                       VIRTIO_RING_F_EVENT_IDX, true),     \
259     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
260                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
261     DEFINE_PROP_BIT64("any_layout", _state, _field, \
262                       VIRTIO_F_ANY_LAYOUT, true), \
263     DEFINE_PROP_BIT64("iommu_platform", _state, _field, \
264                       VIRTIO_F_IOMMU_PLATFORM, false)
265 
266 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
267 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
268 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
269 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
270 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
271 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
272 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
273 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
274 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
275 void virtio_queue_update_used_idx(VirtIODevice *vdev, int n);
276 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
277 uint16_t virtio_get_queue_index(VirtQueue *vq);
278 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
279 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
280                                                 bool with_irqfd);
281 int virtio_device_start_ioeventfd(VirtIODevice *vdev);
282 void virtio_device_stop_ioeventfd(VirtIODevice *vdev);
283 int virtio_device_grab_ioeventfd(VirtIODevice *vdev);
284 void virtio_device_release_ioeventfd(VirtIODevice *vdev);
285 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev);
286 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
287 void virtio_queue_host_notifier_read(EventNotifier *n);
288 void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
289                                                 VirtIOHandleAIOOutput handle_output);
290 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
291 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
292 
293 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
294 {
295     assert(fbit < 64);
296     *features |= (1ULL << fbit);
297 }
298 
299 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
300 {
301     assert(fbit < 64);
302     *features &= ~(1ULL << fbit);
303 }
304 
305 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
306 {
307     assert(fbit < 64);
308     return !!(features & (1ULL << fbit));
309 }
310 
311 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
312                                            unsigned int fbit)
313 {
314     return virtio_has_feature(vdev->guest_features, fbit);
315 }
316 
317 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
318                                            unsigned int fbit)
319 {
320     return virtio_has_feature(vdev->host_features, fbit);
321 }
322 
323 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
324 {
325     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
326         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
327         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
328     }
329     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
330     return false;
331 }
332 #endif
333