diff options
| -rw-r--r-- | docs/interop/vhost-user.txt | 21 | ||||
| -rw-r--r-- | hw/virtio/vhost-user.c | 22 |
2 files changed, 34 insertions, 9 deletions
diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt index c058c407df..534caab18a 100644 --- a/docs/interop/vhost-user.txt +++ b/docs/interop/vhost-user.txt @@ -379,6 +379,7 @@ Protocol features #define VHOST_USER_PROTOCOL_F_CROSS_ENDIAN 6 #define VHOST_USER_PROTOCOL_F_CRYPTO_SESSION 7 #define VHOST_USER_PROTOCOL_F_PAGEFAULT 8 +#define VHOST_USER_PROTOCOL_F_CONFIG 9 Master message types -------------------- @@ -664,7 +665,8 @@ Master message types Master payload: virtio device config space Slave payload: virtio device config space - Submitted by the vhost-user master to fetch the contents of the virtio + When VHOST_USER_PROTOCOL_F_CONFIG is negotiated, this message is + submitted by the vhost-user master to fetch the contents of the virtio device configuration space, vhost-user slave's payload size MUST match master's request, vhost-user slave uses zero length of payload to indicate an error to vhost-user master. The vhost-user master may @@ -677,7 +679,8 @@ Master message types Master payload: virtio device config space Slave payload: N/A - Submitted by the vhost-user master when the Guest changes the virtio + When VHOST_USER_PROTOCOL_F_CONFIG is negotiated, this message is + submitted by the vhost-user master when the Guest changes the virtio device configuration space and also can be used for live migration on the destination host. The vhost-user slave must check the flags field, and slaves MUST NOT accept SET_CONFIG for read-only @@ -766,13 +769,13 @@ Slave message types Slave payload: N/A Master payload: N/A - Vhost-user slave sends such messages to notify that the virtio device's - configuration space has changed, for those host devices which can support - such feature, host driver can send VHOST_USER_GET_CONFIG message to slave - to get the latest content. If VHOST_USER_PROTOCOL_F_REPLY_ACK is - negotiated, and slave set the VHOST_USER_NEED_REPLY flag, master must - respond with zero when operation is successfully completed, or non-zero - otherwise. + When VHOST_USER_PROTOCOL_F_CONFIG is negotiated, vhost-user slave sends + such messages to notify that the virtio device's configuration space has + changed, for those host devices which can support such feature, host + driver can send VHOST_USER_GET_CONFIG message to slave to get the latest + content. If VHOST_USER_PROTOCOL_F_REPLY_ACK is negotiated, and slave set + the VHOST_USER_NEED_REPLY flag, master must respond with zero when + operation is successfully completed, or non-zero otherwise. VHOST_USER_PROTOCOL_F_REPLY_ACK: ------------------------------- diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 44aea5c0a8..38da8692bb 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -46,6 +46,7 @@ enum VhostUserProtocolFeature { VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6, VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7, VHOST_USER_PROTOCOL_F_PAGEFAULT = 8, + VHOST_USER_PROTOCOL_F_CONFIG = 9, VHOST_USER_PROTOCOL_F_MAX }; @@ -1211,6 +1212,17 @@ static int vhost_user_init(struct vhost_dev *dev, void *opaque) dev->protocol_features = protocol_features & VHOST_USER_PROTOCOL_FEATURE_MASK; + + if (!dev->config_ops || !dev->config_ops->vhost_dev_config_notifier) { + /* Don't acknowledge CONFIG feature if device doesn't support it */ + dev->protocol_features &= ~(1ULL << VHOST_USER_PROTOCOL_F_CONFIG); + } else if (!(protocol_features & + (1ULL << VHOST_USER_PROTOCOL_F_CONFIG))) { + error_report("Device expects VHOST_USER_PROTOCOL_F_CONFIG " + "but backend does not support it."); + return -1; + } + err = vhost_user_set_protocol_features(dev, dev->protocol_features); if (err < 0) { return err; @@ -1405,6 +1417,11 @@ static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config, .hdr.size = VHOST_USER_CONFIG_HDR_SIZE + config_len, }; + if (!virtio_has_feature(dev->protocol_features, + VHOST_USER_PROTOCOL_F_CONFIG)) { + return -1; + } + if (config_len > VHOST_USER_MAX_CONFIG_SIZE) { return -1; } @@ -1448,6 +1465,11 @@ static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data, .hdr.size = VHOST_USER_CONFIG_HDR_SIZE + size, }; + if (!virtio_has_feature(dev->protocol_features, + VHOST_USER_PROTOCOL_F_CONFIG)) { + return -1; + } + if (reply_supported) { msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; } |