xref: /openbmc/qemu/include/hw/virtio/virtio.h (revision bc5c4f21)
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     AddressSpace *dma_as;
96     QLIST_HEAD(, VirtQueue) *vector_queues;
97 };
98 
99 typedef struct VirtioDeviceClass {
100     /*< private >*/
101     DeviceClass parent;
102     /*< public >*/
103 
104     /* This is what a VirtioDevice must implement */
105     DeviceRealize realize;
106     DeviceUnrealize unrealize;
107     uint64_t (*get_features)(VirtIODevice *vdev,
108                              uint64_t requested_features,
109                              Error **errp);
110     uint64_t (*bad_features)(VirtIODevice *vdev);
111     void (*set_features)(VirtIODevice *vdev, uint64_t val);
112     int (*validate_features)(VirtIODevice *vdev);
113     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
114     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
115     void (*reset)(VirtIODevice *vdev);
116     void (*set_status)(VirtIODevice *vdev, uint8_t val);
117     /* For transitional devices, this is a bitmap of features
118      * that are only exposed on the legacy interface but not
119      * the modern one.
120      */
121     uint64_t legacy_features;
122     /* Test and clear event pending status.
123      * Should be called after unmask to avoid losing events.
124      * If backend does not support masking,
125      * must check in frontend instead.
126      */
127     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
128     /* Mask/unmask events from this vq. Any events reported
129      * while masked will become pending.
130      * If backend does not support masking,
131      * must mask in frontend instead.
132      */
133     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
134     int (*start_ioeventfd)(VirtIODevice *vdev);
135     void (*stop_ioeventfd)(VirtIODevice *vdev);
136     /* Saving and loading of a device; trying to deprecate save/load
137      * use vmsd for new devices.
138      */
139     void (*save)(VirtIODevice *vdev, QEMUFile *f);
140     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
141     const VMStateDescription *vmsd;
142 } VirtioDeviceClass;
143 
144 void virtio_instance_init_common(Object *proxy_obj, void *data,
145                                  size_t vdev_size, const char *vdev_name);
146 
147 void virtio_init(VirtIODevice *vdev, const char *name,
148                          uint16_t device_id, size_t config_size);
149 void virtio_cleanup(VirtIODevice *vdev);
150 
151 void virtio_error(VirtIODevice *vdev, const char *fmt, ...) GCC_FMT_ATTR(2, 3);
152 
153 /* Set the child bus name. */
154 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
155 
156 typedef void (*VirtIOHandleOutput)(VirtIODevice *, VirtQueue *);
157 
158 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
159                             VirtIOHandleOutput handle_output);
160 
161 void virtio_del_queue(VirtIODevice *vdev, int n);
162 
163 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
164                     unsigned int len);
165 void virtqueue_flush(VirtQueue *vq, unsigned int count);
166 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
167                               unsigned int len);
168 void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem,
169                      unsigned int len);
170 bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
171 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
172                     unsigned int len, unsigned int idx);
173 
174 void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem);
175 void *virtqueue_pop(VirtQueue *vq, size_t sz);
176 unsigned int virtqueue_drop_all(VirtQueue *vq);
177 void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz);
178 void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem);
179 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
180                           unsigned int out_bytes);
181 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
182                                unsigned int *out_bytes,
183                                unsigned max_in_bytes, unsigned max_out_bytes);
184 
185 void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq);
186 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
187 
188 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
189 
190 extern const VMStateInfo virtio_vmstate_info;
191 
192 #define VMSTATE_VIRTIO_DEVICE \
193     {                                         \
194         .name = "virtio",                     \
195         .info = &virtio_vmstate_info,         \
196         .flags = VMS_SINGLE,                  \
197     }
198 
199 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
200 
201 void virtio_notify_config(VirtIODevice *vdev);
202 
203 void virtio_queue_set_notification(VirtQueue *vq, int enable);
204 
205 int virtio_queue_ready(VirtQueue *vq);
206 
207 int virtio_queue_empty(VirtQueue *vq);
208 
209 /* Host binding interface.  */
210 
211 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
212 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
213 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
214 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
215 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
216 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
217 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
218 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
219 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
220 void virtio_config_modern_writeb(VirtIODevice *vdev,
221                                  uint32_t addr, uint32_t data);
222 void virtio_config_modern_writew(VirtIODevice *vdev,
223                                  uint32_t addr, uint32_t data);
224 void virtio_config_modern_writel(VirtIODevice *vdev,
225                                  uint32_t addr, uint32_t data);
226 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
227 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
228 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
229 int virtio_queue_get_num(VirtIODevice *vdev, int n);
230 int virtio_queue_get_max_num(VirtIODevice *vdev, int n);
231 int virtio_get_num_queues(VirtIODevice *vdev);
232 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
233                             hwaddr avail, hwaddr used);
234 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
235 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
236 void virtio_queue_notify(VirtIODevice *vdev, int n);
237 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
238 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
239 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
240 void virtio_reset(void *opaque);
241 void virtio_update_irq(VirtIODevice *vdev);
242 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
243 
244 /* Base devices.  */
245 typedef struct VirtIOBlkConf VirtIOBlkConf;
246 struct virtio_net_conf;
247 typedef struct virtio_serial_conf virtio_serial_conf;
248 typedef struct virtio_input_conf virtio_input_conf;
249 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
250 typedef struct VirtIORNGConf VirtIORNGConf;
251 
252 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
253     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
254                       VIRTIO_RING_F_INDIRECT_DESC, true), \
255     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
256                       VIRTIO_RING_F_EVENT_IDX, true),     \
257     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
258                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
259     DEFINE_PROP_BIT64("any_layout", _state, _field, \
260                       VIRTIO_F_ANY_LAYOUT, true), \
261     DEFINE_PROP_BIT64("iommu_platform", _state, _field, \
262                       VIRTIO_F_IOMMU_PLATFORM, false)
263 
264 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
265 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
266 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
267 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
268 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
269 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
270 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
271 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
272 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
273 void virtio_queue_update_used_idx(VirtIODevice *vdev, int n);
274 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
275 uint16_t virtio_get_queue_index(VirtQueue *vq);
276 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
277 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
278                                                 bool with_irqfd);
279 int virtio_device_start_ioeventfd(VirtIODevice *vdev);
280 void virtio_device_stop_ioeventfd(VirtIODevice *vdev);
281 int virtio_device_grab_ioeventfd(VirtIODevice *vdev);
282 void virtio_device_release_ioeventfd(VirtIODevice *vdev);
283 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev);
284 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
285 void virtio_queue_host_notifier_read(EventNotifier *n);
286 void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
287                                                 void (*fn)(VirtIODevice *,
288                                                            VirtQueue *));
289 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
290 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
291 
292 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
293 {
294     assert(fbit < 64);
295     *features |= (1ULL << fbit);
296 }
297 
298 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
299 {
300     assert(fbit < 64);
301     *features &= ~(1ULL << fbit);
302 }
303 
304 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
305 {
306     assert(fbit < 64);
307     return !!(features & (1ULL << fbit));
308 }
309 
310 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
311                                            unsigned int fbit)
312 {
313     return virtio_has_feature(vdev->guest_features, fbit);
314 }
315 
316 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
317                                            unsigned int fbit)
318 {
319     return virtio_has_feature(vdev->host_features, fbit);
320 }
321 
322 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
323 {
324     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
325         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
326         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
327     }
328     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
329     return false;
330 }
331 #endif
332