xref: /openbmc/qemu/include/hw/virtio/virtio.h (revision b45c03f5)
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[VIRTQUEUE_MAX_SIZE];
50     hwaddr out_addr[VIRTQUEUE_MAX_SIZE];
51     struct iovec in_sg[VIRTQUEUE_MAX_SIZE];
52     struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
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     QLIST_HEAD(, VirtQueue) *vector_queues;
94 };
95 
96 typedef struct VirtioDeviceClass {
97     /*< private >*/
98     DeviceClass parent;
99     /*< public >*/
100 
101     /* This is what a VirtioDevice must implement */
102     DeviceRealize realize;
103     DeviceUnrealize unrealize;
104     uint64_t (*get_features)(VirtIODevice *vdev,
105                              uint64_t requested_features,
106                              Error **errp);
107     uint64_t (*bad_features)(VirtIODevice *vdev);
108     void (*set_features)(VirtIODevice *vdev, uint64_t val);
109     int (*validate_features)(VirtIODevice *vdev);
110     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
111     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
112     void (*reset)(VirtIODevice *vdev);
113     void (*set_status)(VirtIODevice *vdev, uint8_t val);
114     /* Test and clear event pending status.
115      * Should be called after unmask to avoid losing events.
116      * If backend does not support masking,
117      * must check in frontend instead.
118      */
119     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
120     /* Mask/unmask events from this vq. Any events reported
121      * while masked will become pending.
122      * If backend does not support masking,
123      * must mask in frontend instead.
124      */
125     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
126     void (*save)(VirtIODevice *vdev, QEMUFile *f);
127     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
128 } VirtioDeviceClass;
129 
130 void virtio_instance_init_common(Object *proxy_obj, void *data,
131                                  size_t vdev_size, const char *vdev_name);
132 
133 void virtio_init(VirtIODevice *vdev, const char *name,
134                          uint16_t device_id, size_t config_size);
135 void virtio_cleanup(VirtIODevice *vdev);
136 
137 /* Set the child bus name. */
138 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
139 
140 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
141                             void (*handle_output)(VirtIODevice *,
142                                                   VirtQueue *));
143 
144 void virtio_del_queue(VirtIODevice *vdev, int n);
145 
146 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
147                     unsigned int len);
148 void virtqueue_flush(VirtQueue *vq, unsigned int count);
149 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
150                     unsigned int len, unsigned int idx);
151 
152 void virtqueue_map_sg(struct iovec *sg, hwaddr *addr,
153     size_t num_sg, int is_write);
154 int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem);
155 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
156                           unsigned int out_bytes);
157 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
158                                unsigned int *out_bytes,
159                                unsigned max_in_bytes, unsigned max_out_bytes);
160 
161 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
162 
163 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
164 
165 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
166 
167 void virtio_notify_config(VirtIODevice *vdev);
168 
169 void virtio_queue_set_notification(VirtQueue *vq, int enable);
170 
171 int virtio_queue_ready(VirtQueue *vq);
172 
173 int virtio_queue_empty(VirtQueue *vq);
174 
175 /* Host binding interface.  */
176 
177 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
178 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
179 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
180 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
181 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
182 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
183 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
184 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
185 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
186 void virtio_config_modern_writeb(VirtIODevice *vdev,
187                                  uint32_t addr, uint32_t data);
188 void virtio_config_modern_writew(VirtIODevice *vdev,
189                                  uint32_t addr, uint32_t data);
190 void virtio_config_modern_writel(VirtIODevice *vdev,
191                                  uint32_t addr, uint32_t data);
192 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
193 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
194 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
195 int virtio_queue_get_num(VirtIODevice *vdev, int n);
196 int virtio_get_num_queues(VirtIODevice *vdev);
197 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
198                             hwaddr avail, hwaddr used);
199 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
200 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
201 void virtio_queue_notify(VirtIODevice *vdev, int n);
202 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
203 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
204 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
205 void virtio_reset(void *opaque);
206 void virtio_update_irq(VirtIODevice *vdev);
207 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
208 
209 /* Base devices.  */
210 typedef struct VirtIOBlkConf VirtIOBlkConf;
211 struct virtio_net_conf;
212 typedef struct virtio_serial_conf virtio_serial_conf;
213 typedef struct virtio_input_conf virtio_input_conf;
214 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
215 typedef struct VirtIORNGConf VirtIORNGConf;
216 
217 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
218     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
219                       VIRTIO_RING_F_INDIRECT_DESC, true), \
220     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
221                       VIRTIO_RING_F_EVENT_IDX, true),     \
222     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
223                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
224     DEFINE_PROP_BIT64("any_layout", _state, _field, \
225                       VIRTIO_F_ANY_LAYOUT, true)
226 
227 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
228 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
229 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
230 hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n);
231 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
232 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
233 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
234 hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n);
235 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
236 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
237 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
238 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
239 uint16_t virtio_get_queue_index(VirtQueue *vq);
240 int virtio_queue_get_id(VirtQueue *vq);
241 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
242 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
243                                                 bool with_irqfd);
244 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
245 void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign,
246                                                bool set_handler);
247 void virtio_queue_notify_vq(VirtQueue *vq);
248 void virtio_irq(VirtQueue *vq);
249 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
250 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
251 
252 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
253 {
254     assert(fbit < 64);
255     *features |= (1ULL << fbit);
256 }
257 
258 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
259 {
260     assert(fbit < 64);
261     *features &= ~(1ULL << fbit);
262 }
263 
264 static inline bool __virtio_has_feature(uint64_t features, unsigned int fbit)
265 {
266     assert(fbit < 64);
267     return !!(features & (1ULL << fbit));
268 }
269 
270 static inline bool virtio_has_feature(VirtIODevice *vdev, unsigned int fbit)
271 {
272     return __virtio_has_feature(vdev->guest_features, fbit);
273 }
274 
275 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
276                                            unsigned int fbit)
277 {
278     return __virtio_has_feature(vdev->host_features, fbit);
279 }
280 
281 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
282 {
283     if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
284         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
285         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
286     }
287     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
288     return false;
289 }
290 #endif
291