include/hw/virtio/virtio.h

   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 #ifdef CONFIG_VIRTFS
  23 #include "hw/virtio/virtio-9p.h"
  24 #endif
  25
  26 /* from Linux's linux/virtio_config.h */
  27
  28 /* Status byte for guest to report progress, and synchronize features. */
  29 /* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */
  30 #define VIRTIO_CONFIG_S_ACKNOWLEDGE     1
  31 /* We have found a driver for the device. */
  32 #define VIRTIO_CONFIG_S_DRIVER          2
  33 /* Driver has used its parts of the config, and is happy */
  34 #define VIRTIO_CONFIG_S_DRIVER_OK       4
  35 /* We've given up on this device. */
  36 #define VIRTIO_CONFIG_S_FAILED          0x80
  37
  38 /* Some virtio feature bits (currently bits 28 through 31) are reserved for the
  39  * transport being used (eg. virtio_ring), the rest are per-device feature bits. */
  40 #define VIRTIO_TRANSPORT_F_START        28
  41 #define VIRTIO_TRANSPORT_F_END          32
  42
  43 /* We notify when the ring is completely used, even if the guest is suppressing
  44  * callbacks */
  45 #define VIRTIO_F_NOTIFY_ON_EMPTY        24
  46 /* Can the device handle any descriptor layout? */
  47 #define VIRTIO_F_ANY_LAYOUT             27
  48 /* We support indirect buffer descriptors */
  49 #define VIRTIO_RING_F_INDIRECT_DESC     28
  50 /* The Guest publishes the used index for which it expects an interrupt
  51  * at the end of the avail ring. Host should ignore the avail->flags field. */
  52 /* The Host publishes the avail index for which it expects a kick
  53  * at the end of the used ring. Guest should ignore the used->flags field. */
  54 #define VIRTIO_RING_F_EVENT_IDX         29
  55 /* A guest should never accept this.  It implies negotiation is broken. */
  56 #define VIRTIO_F_BAD_FEATURE            30
  57
  58 /* from Linux's linux/virtio_ring.h */
  59
  60 /* This marks a buffer as continuing via the next field. */
  61 #define VRING_DESC_F_NEXT       1
  62 /* This marks a buffer as write-only (otherwise read-only). */
  63 #define VRING_DESC_F_WRITE      2
  64 /* This means the buffer contains a list of buffer descriptors. */
  65 #define VRING_DESC_F_INDIRECT  4
  66
  67 /* This means don't notify other side when buffer added. */
  68 #define VRING_USED_F_NO_NOTIFY  1
  69 /* This means don't interrupt guest when buffer consumed. */
  70 #define VRING_AVAIL_F_NO_INTERRUPT      1
  71
  72 struct VirtQueue;
  73
  74 static inline hwaddr vring_align(hwaddr addr,
  75                                              unsigned long align)
  76 {
  77     return (addr + align - 1) & ~(align - 1);
  78 }
  79
  80 typedef struct VirtQueue VirtQueue;
  81
  82 #define VIRTQUEUE_MAX_SIZE 1024
  83
  84 typedef struct VirtQueueElement
  85 {
  86     unsigned int index;
  87     unsigned int out_num;
  88     unsigned int in_num;
  89     hwaddr in_addr[VIRTQUEUE_MAX_SIZE];
  90     hwaddr out_addr[VIRTQUEUE_MAX_SIZE];
  91     struct iovec in_sg[VIRTQUEUE_MAX_SIZE];
  92     struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
  93 } VirtQueueElement;
  94
  95 #define VIRTIO_PCI_QUEUE_MAX 64
  96
  97 #define VIRTIO_NO_VECTOR 0xffff
  98
  99 #define TYPE_VIRTIO_DEVICE "virtio-device"
 100 #define VIRTIO_DEVICE_GET_CLASS(obj) \
 101         OBJECT_GET_CLASS(VirtioDeviceClass, obj, TYPE_VIRTIO_DEVICE)
 102 #define VIRTIO_DEVICE_CLASS(klass) \
 103         OBJECT_CLASS_CHECK(VirtioDeviceClass, klass, TYPE_VIRTIO_DEVICE)
 104 #define VIRTIO_DEVICE(obj) \
 105         OBJECT_CHECK(VirtIODevice, (obj), TYPE_VIRTIO_DEVICE)
 106
 107 enum virtio_device_endian {
 108     VIRTIO_DEVICE_ENDIAN_UNKNOWN,
 109     VIRTIO_DEVICE_ENDIAN_LITTLE,
 110     VIRTIO_DEVICE_ENDIAN_BIG,
 111 };
 112
 113 struct VirtIODevice
 114 {
 115     DeviceState parent_obj;
 116     const char *name;
 117     uint8_t status;
 118     uint8_t isr;
 119     uint16_t queue_sel;
 120     uint32_t guest_features;
 121     size_t config_len;
 122     void *config;
 123     uint16_t config_vector;
 124     int nvectors;
 125     VirtQueue *vq;
 126     uint16_t device_id;
 127     bool vm_running;
 128     VMChangeStateEntry *vmstate;
 129     char *bus_name;
 130     uint8_t device_endian;
 131 };
 132
 133 typedef struct VirtioDeviceClass {
 134     /*< private >*/
 135     DeviceClass parent;
 136     /*< public >*/
 137
 138     /* This is what a VirtioDevice must implement */
 139     DeviceRealize realize;
 140     DeviceUnrealize unrealize;
 141     uint32_t (*get_features)(VirtIODevice *vdev, uint32_t requested_features);
 142     uint32_t (*bad_features)(VirtIODevice *vdev);
 143     void (*set_features)(VirtIODevice *vdev, uint32_t val);
 144     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
 145     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
 146     void (*reset)(VirtIODevice *vdev);
 147     void (*set_status)(VirtIODevice *vdev, uint8_t val);
 148     /* Test and clear event pending status.
 149      * Should be called after unmask to avoid losing events.
 150      * If backend does not support masking,
 151      * must check in frontend instead.
 152      */
 153     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
 154     /* Mask/unmask events from this vq. Any events reported
 155      * while masked will become pending.
 156      * If backend does not support masking,
 157      * must mask in frontend instead.
 158      */
 159     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
 160     void (*save)(VirtIODevice *vdev, QEMUFile *f);
 161     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
 162 } VirtioDeviceClass;
 163
 164 void virtio_instance_init_common(Object *proxy_obj, void *data,
 165                                  size_t vdev_size, const char *vdev_name);
 166
 167 void virtio_init(VirtIODevice *vdev, const char *name,
 168                          uint16_t device_id, size_t config_size);
 169 void virtio_cleanup(VirtIODevice *vdev);
 170
 171 /* Set the child bus name. */
 172 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
 173
 174 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
 175                             void (*handle_output)(VirtIODevice *,
 176                                                   VirtQueue *));
 177
 178 void virtio_del_queue(VirtIODevice *vdev, int n);
 179
 180 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
 181                     unsigned int len);
 182 void virtqueue_flush(VirtQueue *vq, unsigned int count);
 183 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
 184                     unsigned int len, unsigned int idx);
 185
 186 void virtqueue_map_sg(struct iovec *sg, hwaddr *addr,
 187     size_t num_sg, int is_write);
 188 int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem);
 189 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
 190                           unsigned int out_bytes);
 191 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
 192                                unsigned int *out_bytes,
 193                                unsigned max_in_bytes, unsigned max_out_bytes);
 194
 195 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
 196
 197 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
 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 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
 218 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
 219 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
 220 int virtio_queue_get_num(VirtIODevice *vdev, int n);
 221 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
 222 void virtio_queue_notify(VirtIODevice *vdev, int n);
 223 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
 224 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
 225 void virtio_set_status(VirtIODevice *vdev, uint8_t val);
 226 void virtio_reset(void *opaque);
 227 void virtio_update_irq(VirtIODevice *vdev);
 228 int virtio_set_features(VirtIODevice *vdev, uint32_t val);
 229
 230 /* Base devices.  */
 231 typedef struct VirtIOBlkConf VirtIOBlkConf;
 232 struct virtio_net_conf;
 233 typedef struct virtio_serial_conf virtio_serial_conf;
 234 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
 235 typedef struct VirtIORNGConf VirtIORNGConf;
 236
 237 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
 238         DEFINE_PROP_BIT("indirect_desc", _state, _field, \
 239                         VIRTIO_RING_F_INDIRECT_DESC, true), \
 240         DEFINE_PROP_BIT("event_idx", _state, _field, \
 241                         VIRTIO_RING_F_EVENT_IDX, true)
 242
 243 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
 244 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
 245 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
 246 hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n);
 247 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
 248 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
 249 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
 250 hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n);
 251 uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
 252 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
 253 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
 254 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
 255 uint16_t virtio_get_queue_index(VirtQueue *vq);
 256 int virtio_queue_get_id(VirtQueue *vq);
 257 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
 258 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
 259                                                 bool with_irqfd);
 260 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
 261 void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign,
 262                                                bool set_handler);
 263 void virtio_queue_notify_vq(VirtQueue *vq);
 264 void virtio_irq(VirtQueue *vq);
 265
 266 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
 267 {
 268     assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
 269     return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
 270 }
 271 #endif