diff options
| -rw-r--r-- | docs/interop/vhost-user.txt | 5 | ||||
| -rw-r--r-- | hw/virtio/vhost-user.c | 27 |
2 files changed, 22 insertions, 10 deletions
diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt index 534caab18a..682a683eb4 100644 --- a/docs/interop/vhost-user.txt +++ b/docs/interop/vhost-user.txt @@ -367,6 +367,10 @@ The fd is provided via VHOST_USER_SET_SLAVE_REQ_FD ancillary data. A slave may then send VHOST_USER_SLAVE_* messages to the master using this fd communication channel. +If VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD protocol feature is negotiated, +slave can send file descriptors (at most 8 descriptors in each message) +to master via ancillary data using this fd communication channel. + Protocol features ----------------- @@ -380,6 +384,7 @@ Protocol features #define VHOST_USER_PROTOCOL_F_CRYPTO_SESSION 7 #define VHOST_USER_PROTOCOL_F_PAGEFAULT 8 #define VHOST_USER_PROTOCOL_F_CONFIG 9 +#define VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD 10 Master message types -------------------- diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index da0756effe..75a3faef2a 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -30,6 +30,7 @@ #define VHOST_MEMORY_MAX_NREGIONS 8 #define VHOST_USER_F_PROTOCOL_FEATURES 30 +#define VHOST_USER_SLAVE_MAX_FDS 8 /* * Maximum size of virtio device config space @@ -47,6 +48,7 @@ enum VhostUserProtocolFeature { VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7, VHOST_USER_PROTOCOL_F_PAGEFAULT = 8, VHOST_USER_PROTOCOL_F_CONFIG = 9, + VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = 10, VHOST_USER_PROTOCOL_F_MAX }; @@ -854,10 +856,10 @@ static void slave_read(void *opaque) int size, ret = 0; struct iovec iov; struct msghdr msgh; - int fd = -1; + int fd[VHOST_USER_SLAVE_MAX_FDS]; char control[CMSG_SPACE(sizeof(fd))]; struct cmsghdr *cmsg; - size_t fdsize; + int i, fdsize = 0; memset(&msgh, 0, sizeof(msgh)); msgh.msg_iov = &iov; @@ -865,6 +867,8 @@ static void slave_read(void *opaque) msgh.msg_control = control; msgh.msg_controllen = sizeof(control); + memset(fd, -1, sizeof(fd)); + /* Read header */ iov.iov_base = &hdr; iov.iov_len = VHOST_USER_HDR_SIZE; @@ -885,7 +889,7 @@ static void slave_read(void *opaque) if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { fdsize = cmsg->cmsg_len - CMSG_LEN(0); - memcpy(&fd, CMSG_DATA(cmsg), fdsize); + memcpy(fd, CMSG_DATA(cmsg), fdsize); break; } } @@ -913,14 +917,15 @@ static void slave_read(void *opaque) break; default: error_report("Received unexpected msg type."); - if (fd != -1) { - close(fd); - } ret = -EINVAL; } - /* Message handlers need to make sure that fd will be consumed. */ - fd = -1; + /* Close the remaining file descriptors. */ + for (i = 0; i < fdsize; i++) { + if (fd[i] != -1) { + close(fd[i]); + } + } /* * REPLY_ACK feature handling. Other reply types has to be managed @@ -954,8 +959,10 @@ err: qemu_set_fd_handler(u->slave_fd, NULL, NULL, NULL); close(u->slave_fd); u->slave_fd = -1; - if (fd != -1) { - close(fd); + for (i = 0; i < fdsize; i++) { + if (fd[i] != -1) { + close(fd[i]); + } } return; } |