From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- net/vmw_vsock/hyperv_transport.c | 956 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 956 insertions(+) create mode 100644 net/vmw_vsock/hyperv_transport.c (limited to 'net/vmw_vsock/hyperv_transport.c') diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c new file mode 100644 index 000000000..59c3e2697 --- /dev/null +++ b/net/vmw_vsock/hyperv_transport.c @@ -0,0 +1,956 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Hyper-V transport for vsock + * + * Hyper-V Sockets supplies a byte-stream based communication mechanism + * between the host and the VM. This driver implements the necessary + * support in the VM by introducing the new vsock transport. + * + * Copyright (c) 2017, Microsoft Corporation. + */ +#include +#include +#include +#include +#include +#include + +/* Older (VMBUS version 'VERSION_WIN10' or before) Windows hosts have some + * stricter requirements on the hv_sock ring buffer size of six 4K pages. + * hyperv-tlfs defines HV_HYP_PAGE_SIZE as 4K. Newer hosts don't have this + * limitation; but, keep the defaults the same for compat. + */ +#define RINGBUFFER_HVS_RCV_SIZE (HV_HYP_PAGE_SIZE * 6) +#define RINGBUFFER_HVS_SND_SIZE (HV_HYP_PAGE_SIZE * 6) +#define RINGBUFFER_HVS_MAX_SIZE (HV_HYP_PAGE_SIZE * 64) + +/* The MTU is 16KB per the host side's design */ +#define HVS_MTU_SIZE (1024 * 16) + +/* How long to wait for graceful shutdown of a connection */ +#define HVS_CLOSE_TIMEOUT (8 * HZ) + +struct vmpipe_proto_header { + u32 pkt_type; + u32 data_size; +}; + +/* For recv, we use the VMBus in-place packet iterator APIs to directly copy + * data from the ringbuffer into the userspace buffer. + */ +struct hvs_recv_buf { + /* The header before the payload data */ + struct vmpipe_proto_header hdr; + + /* The payload */ + u8 data[HVS_MTU_SIZE]; +}; + +/* We can send up to HVS_MTU_SIZE bytes of payload to the host, but let's use + * a smaller size, i.e. HVS_SEND_BUF_SIZE, to maximize concurrency between the + * guest and the host processing as one VMBUS packet is the smallest processing + * unit. + * + * Note: the buffer can be eliminated in the future when we add new VMBus + * ringbuffer APIs that allow us to directly copy data from userspace buffer + * to VMBus ringbuffer. + */ +#define HVS_SEND_BUF_SIZE \ + (HV_HYP_PAGE_SIZE - sizeof(struct vmpipe_proto_header)) + +struct hvs_send_buf { + /* The header before the payload data */ + struct vmpipe_proto_header hdr; + + /* The payload */ + u8 data[HVS_SEND_BUF_SIZE]; +}; + +#define HVS_HEADER_LEN (sizeof(struct vmpacket_descriptor) + \ + sizeof(struct vmpipe_proto_header)) + +/* See 'prev_indices' in hv_ringbuffer_read(), hv_ringbuffer_write(), and + * __hv_pkt_iter_next(). + */ +#define VMBUS_PKT_TRAILER_SIZE (sizeof(u64)) + +#define HVS_PKT_LEN(payload_len) (HVS_HEADER_LEN + \ + ALIGN((payload_len), 8) + \ + VMBUS_PKT_TRAILER_SIZE) + +/* Upper bound on the size of a VMbus packet for hv_sock */ +#define HVS_MAX_PKT_SIZE HVS_PKT_LEN(HVS_MTU_SIZE) + +union hvs_service_id { + guid_t srv_id; + + struct { + unsigned int svm_port; + unsigned char b[sizeof(guid_t) - sizeof(unsigned int)]; + }; +}; + +/* Per-socket state (accessed via vsk->trans) */ +struct hvsock { + struct vsock_sock *vsk; + + guid_t vm_srv_id; + guid_t host_srv_id; + + struct vmbus_channel *chan; + struct vmpacket_descriptor *recv_desc; + + /* The length of the payload not delivered to userland yet */ + u32 recv_data_len; + /* The offset of the payload */ + u32 recv_data_off; + + /* Have we sent the zero-length packet (FIN)? */ + bool fin_sent; +}; + +/* In the VM, we support Hyper-V Sockets with AF_VSOCK, and the endpoint is + * (see struct sockaddr_vm). Note: cid is not really used here: + * when we write apps to connect to the host, we can only use VMADDR_CID_ANY + * or VMADDR_CID_HOST (both are equivalent) as the remote cid, and when we + * write apps to bind() & listen() in the VM, we can only use VMADDR_CID_ANY + * as the local cid. + * + * On the host, Hyper-V Sockets are supported by Winsock AF_HYPERV: + * https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/user- + * guide/make-integration-service, and the endpoint is with + * the below sockaddr: + * + * struct SOCKADDR_HV + * { + * ADDRESS_FAMILY Family; + * USHORT Reserved; + * GUID VmId; + * GUID ServiceId; + * }; + * Note: VmID is not used by Linux VM and actually it isn't transmitted via + * VMBus, because here it's obvious the host and the VM can easily identify + * each other. Though the VmID is useful on the host, especially in the case + * of Windows container, Linux VM doesn't need it at all. + * + * To make use of the AF_VSOCK infrastructure in Linux VM, we have to limit + * the available GUID space of SOCKADDR_HV so that we can create a mapping + * between AF_VSOCK port and SOCKADDR_HV Service GUID. The rule of writing + * Hyper-V Sockets apps on the host and in Linux VM is: + * + **************************************************************************** + * The only valid Service GUIDs, from the perspectives of both the host and * + * Linux VM, that can be connected by the other end, must conform to this * + * format: -facb-11e6-bd58-64006a7986d3. * + **************************************************************************** + * + * When we write apps on the host to connect(), the GUID ServiceID is used. + * When we write apps in Linux VM to connect(), we only need to specify the + * port and the driver will form the GUID and use that to request the host. + * + */ + +/* 00000000-facb-11e6-bd58-64006a7986d3 */ +static const guid_t srv_id_template = + GUID_INIT(0x00000000, 0xfacb, 0x11e6, 0xbd, 0x58, + 0x64, 0x00, 0x6a, 0x79, 0x86, 0xd3); + +static bool hvs_check_transport(struct vsock_sock *vsk); + +static bool is_valid_srv_id(const guid_t *id) +{ + return !memcmp(&id->b[4], &srv_id_template.b[4], sizeof(guid_t) - 4); +} + +static unsigned int get_port_by_srv_id(const guid_t *svr_id) +{ + return *((unsigned int *)svr_id); +} + +static void hvs_addr_init(struct sockaddr_vm *addr, const guid_t *svr_id) +{ + unsigned int port = get_port_by_srv_id(svr_id); + + vsock_addr_init(addr, VMADDR_CID_ANY, port); +} + +static void hvs_set_channel_pending_send_size(struct vmbus_channel *chan) +{ + set_channel_pending_send_size(chan, + HVS_PKT_LEN(HVS_SEND_BUF_SIZE)); + + virt_mb(); +} + +static bool hvs_channel_readable(struct vmbus_channel *chan) +{ + u32 readable = hv_get_bytes_to_read(&chan->inbound); + + /* 0-size payload means FIN */ + return readable >= HVS_PKT_LEN(0); +} + +static int hvs_channel_readable_payload(struct vmbus_channel *chan) +{ + u32 readable = hv_get_bytes_to_read(&chan->inbound); + + if (readable > HVS_PKT_LEN(0)) { + /* At least we have 1 byte to read. We don't need to return + * the exact readable bytes: see vsock_stream_recvmsg() -> + * vsock_stream_has_data(). + */ + return 1; + } + + if (readable == HVS_PKT_LEN(0)) { + /* 0-size payload means FIN */ + return 0; + } + + /* No payload or FIN */ + return -1; +} + +static size_t hvs_channel_writable_bytes(struct vmbus_channel *chan) +{ + u32 writeable = hv_get_bytes_to_write(&chan->outbound); + size_t ret; + + /* The ringbuffer mustn't be 100% full, and we should reserve a + * zero-length-payload packet for the FIN: see hv_ringbuffer_write() + * and hvs_shutdown(). + */ + if (writeable <= HVS_PKT_LEN(1) + HVS_PKT_LEN(0)) + return 0; + + ret = writeable - HVS_PKT_LEN(1) - HVS_PKT_LEN(0); + + return round_down(ret, 8); +} + +static int __hvs_send_data(struct vmbus_channel *chan, + struct vmpipe_proto_header *hdr, + size_t to_write) +{ + hdr->pkt_type = 1; + hdr->data_size = to_write; + return vmbus_sendpacket(chan, hdr, sizeof(*hdr) + to_write, + 0, VM_PKT_DATA_INBAND, 0); +} + +static int hvs_send_data(struct vmbus_channel *chan, + struct hvs_send_buf *send_buf, size_t to_write) +{ + return __hvs_send_data(chan, &send_buf->hdr, to_write); +} + +static void hvs_channel_cb(void *ctx) +{ + struct sock *sk = (struct sock *)ctx; + struct vsock_sock *vsk = vsock_sk(sk); + struct hvsock *hvs = vsk->trans; + struct vmbus_channel *chan = hvs->chan; + + if (hvs_channel_readable(chan)) + sk->sk_data_ready(sk); + + if (hv_get_bytes_to_write(&chan->outbound) > 0) + sk->sk_write_space(sk); +} + +static void hvs_do_close_lock_held(struct vsock_sock *vsk, + bool cancel_timeout) +{ + struct sock *sk = sk_vsock(vsk); + + sock_set_flag(sk, SOCK_DONE); + vsk->peer_shutdown = SHUTDOWN_MASK; + if (vsock_stream_has_data(vsk) <= 0) + sk->sk_state = TCP_CLOSING; + sk->sk_state_change(sk); + if (vsk->close_work_scheduled && + (!cancel_timeout || cancel_delayed_work(&vsk->close_work))) { + vsk->close_work_scheduled = false; + vsock_remove_sock(vsk); + + /* Release the reference taken while scheduling the timeout */ + sock_put(sk); + } +} + +static void hvs_close_connection(struct vmbus_channel *chan) +{ + struct sock *sk = get_per_channel_state(chan); + + lock_sock(sk); + hvs_do_close_lock_held(vsock_sk(sk), true); + release_sock(sk); + + /* Release the refcnt for the channel that's opened in + * hvs_open_connection(). + */ + sock_put(sk); +} + +static void hvs_open_connection(struct vmbus_channel *chan) +{ + guid_t *if_instance, *if_type; + unsigned char conn_from_host; + + struct sockaddr_vm addr; + struct sock *sk, *new = NULL; + struct vsock_sock *vnew = NULL; + struct hvsock *hvs = NULL; + struct hvsock *hvs_new = NULL; + int rcvbuf; + int ret; + int sndbuf; + + if_type = &chan->offermsg.offer.if_type; + if_instance = &chan->offermsg.offer.if_instance; + conn_from_host = chan->offermsg.offer.u.pipe.user_def[0]; + if (!is_valid_srv_id(if_type)) + return; + + hvs_addr_init(&addr, conn_from_host ? if_type : if_instance); + sk = vsock_find_bound_socket(&addr); + if (!sk) + return; + + lock_sock(sk); + if ((conn_from_host && sk->sk_state != TCP_LISTEN) || + (!conn_from_host && sk->sk_state != TCP_SYN_SENT)) + goto out; + + if (conn_from_host) { + if (sk->sk_ack_backlog >= sk->sk_max_ack_backlog) + goto out; + + new = vsock_create_connected(sk); + if (!new) + goto out; + + new->sk_state = TCP_SYN_SENT; + vnew = vsock_sk(new); + + hvs_addr_init(&vnew->local_addr, if_type); + + /* Remote peer is always the host */ + vsock_addr_init(&vnew->remote_addr, + VMADDR_CID_HOST, VMADDR_PORT_ANY); + vnew->remote_addr.svm_port = get_port_by_srv_id(if_instance); + ret = vsock_assign_transport(vnew, vsock_sk(sk)); + /* Transport assigned (looking at remote_addr) must be the + * same where we received the request. + */ + if (ret || !hvs_check_transport(vnew)) { + sock_put(new); + goto out; + } + hvs_new = vnew->trans; + hvs_new->chan = chan; + } else { + hvs = vsock_sk(sk)->trans; + hvs->chan = chan; + } + + set_channel_read_mode(chan, HV_CALL_DIRECT); + + /* Use the socket buffer sizes as hints for the VMBUS ring size. For + * server side sockets, 'sk' is the parent socket and thus, this will + * allow the child sockets to inherit the size from the parent. Keep + * the mins to the default value and align to page size as per VMBUS + * requirements. + * For the max, the socket core library will limit the socket buffer + * size that can be set by the user, but, since currently, the hv_sock + * VMBUS ring buffer is physically contiguous allocation, restrict it + * further. + * Older versions of hv_sock host side code cannot handle bigger VMBUS + * ring buffer size. Use the version number to limit the change to newer + * versions. + */ + if (vmbus_proto_version < VERSION_WIN10_V5) { + sndbuf = RINGBUFFER_HVS_SND_SIZE; + rcvbuf = RINGBUFFER_HVS_RCV_SIZE; + } else { + sndbuf = max_t(int, sk->sk_sndbuf, RINGBUFFER_HVS_SND_SIZE); + sndbuf = min_t(int, sndbuf, RINGBUFFER_HVS_MAX_SIZE); + sndbuf = ALIGN(sndbuf, HV_HYP_PAGE_SIZE); + rcvbuf = max_t(int, sk->sk_rcvbuf, RINGBUFFER_HVS_RCV_SIZE); + rcvbuf = min_t(int, rcvbuf, RINGBUFFER_HVS_MAX_SIZE); + rcvbuf = ALIGN(rcvbuf, HV_HYP_PAGE_SIZE); + } + + chan->max_pkt_size = HVS_MAX_PKT_SIZE; + + ret = vmbus_open(chan, sndbuf, rcvbuf, NULL, 0, hvs_channel_cb, + conn_from_host ? new : sk); + if (ret != 0) { + if (conn_from_host) { + hvs_new->chan = NULL; + sock_put(new); + } else { + hvs->chan = NULL; + } + goto out; + } + + set_per_channel_state(chan, conn_from_host ? new : sk); + + /* This reference will be dropped by hvs_close_connection(). */ + sock_hold(conn_from_host ? new : sk); + vmbus_set_chn_rescind_callback(chan, hvs_close_connection); + + /* Set the pending send size to max packet size to always get + * notifications from the host when there is enough writable space. + * The host is optimized to send notifications only when the pending + * size boundary is crossed, and not always. + */ + hvs_set_channel_pending_send_size(chan); + + if (conn_from_host) { + new->sk_state = TCP_ESTABLISHED; + sk_acceptq_added(sk); + + hvs_new->vm_srv_id = *if_type; + hvs_new->host_srv_id = *if_instance; + + vsock_insert_connected(vnew); + + vsock_enqueue_accept(sk, new); + } else { + sk->sk_state = TCP_ESTABLISHED; + sk->sk_socket->state = SS_CONNECTED; + + vsock_insert_connected(vsock_sk(sk)); + } + + sk->sk_state_change(sk); + +out: + /* Release refcnt obtained when we called vsock_find_bound_socket() */ + sock_put(sk); + + release_sock(sk); +} + +static u32 hvs_get_local_cid(void) +{ + return VMADDR_CID_ANY; +} + +static int hvs_sock_init(struct vsock_sock *vsk, struct vsock_sock *psk) +{ + struct hvsock *hvs; + struct sock *sk = sk_vsock(vsk); + + hvs = kzalloc(sizeof(*hvs), GFP_KERNEL); + if (!hvs) + return -ENOMEM; + + vsk->trans = hvs; + hvs->vsk = vsk; + sk->sk_sndbuf = RINGBUFFER_HVS_SND_SIZE; + sk->sk_rcvbuf = RINGBUFFER_HVS_RCV_SIZE; + return 0; +} + +static int hvs_connect(struct vsock_sock *vsk) +{ + union hvs_service_id vm, host; + struct hvsock *h = vsk->trans; + + vm.srv_id = srv_id_template; + vm.svm_port = vsk->local_addr.svm_port; + h->vm_srv_id = vm.srv_id; + + host.srv_id = srv_id_template; + host.svm_port = vsk->remote_addr.svm_port; + h->host_srv_id = host.srv_id; + + return vmbus_send_tl_connect_request(&h->vm_srv_id, &h->host_srv_id); +} + +static void hvs_shutdown_lock_held(struct hvsock *hvs, int mode) +{ + struct vmpipe_proto_header hdr; + + if (hvs->fin_sent || !hvs->chan) + return; + + /* It can't fail: see hvs_channel_writable_bytes(). */ + (void)__hvs_send_data(hvs->chan, &hdr, 0); + hvs->fin_sent = true; +} + +static int hvs_shutdown(struct vsock_sock *vsk, int mode) +{ + if (!(mode & SEND_SHUTDOWN)) + return 0; + + hvs_shutdown_lock_held(vsk->trans, mode); + return 0; +} + +static void hvs_close_timeout(struct work_struct *work) +{ + struct vsock_sock *vsk = + container_of(work, struct vsock_sock, close_work.work); + struct sock *sk = sk_vsock(vsk); + + sock_hold(sk); + lock_sock(sk); + if (!sock_flag(sk, SOCK_DONE)) + hvs_do_close_lock_held(vsk, false); + + vsk->close_work_scheduled = false; + release_sock(sk); + sock_put(sk); +} + +/* Returns true, if it is safe to remove socket; false otherwise */ +static bool hvs_close_lock_held(struct vsock_sock *vsk) +{ + struct sock *sk = sk_vsock(vsk); + + if (!(sk->sk_state == TCP_ESTABLISHED || + sk->sk_state == TCP_CLOSING)) + return true; + + if ((sk->sk_shutdown & SHUTDOWN_MASK) != SHUTDOWN_MASK) + hvs_shutdown_lock_held(vsk->trans, SHUTDOWN_MASK); + + if (sock_flag(sk, SOCK_DONE)) + return true; + + /* This reference will be dropped by the delayed close routine */ + sock_hold(sk); + INIT_DELAYED_WORK(&vsk->close_work, hvs_close_timeout); + vsk->close_work_scheduled = true; + schedule_delayed_work(&vsk->close_work, HVS_CLOSE_TIMEOUT); + return false; +} + +static void hvs_release(struct vsock_sock *vsk) +{ + bool remove_sock; + + remove_sock = hvs_close_lock_held(vsk); + if (remove_sock) + vsock_remove_sock(vsk); +} + +static void hvs_destruct(struct vsock_sock *vsk) +{ + struct hvsock *hvs = vsk->trans; + struct vmbus_channel *chan = hvs->chan; + + if (chan) + vmbus_hvsock_device_unregister(chan); + + kfree(hvs); +} + +static int hvs_dgram_bind(struct vsock_sock *vsk, struct sockaddr_vm *addr) +{ + return -EOPNOTSUPP; +} + +static int hvs_dgram_dequeue(struct vsock_sock *vsk, struct msghdr *msg, + size_t len, int flags) +{ + return -EOPNOTSUPP; +} + +static int hvs_dgram_enqueue(struct vsock_sock *vsk, + struct sockaddr_vm *remote, struct msghdr *msg, + size_t dgram_len) +{ + return -EOPNOTSUPP; +} + +static bool hvs_dgram_allow(u32 cid, u32 port) +{ + return false; +} + +static int hvs_update_recv_data(struct hvsock *hvs) +{ + struct hvs_recv_buf *recv_buf; + u32 pkt_len, payload_len; + + pkt_len = hv_pkt_len(hvs->recv_desc); + + if (pkt_len < HVS_HEADER_LEN) + return -EIO; + + recv_buf = (struct hvs_recv_buf *)(hvs->recv_desc + 1); + payload_len = recv_buf->hdr.data_size; + + if (payload_len > pkt_len - HVS_HEADER_LEN || + payload_len > HVS_MTU_SIZE) + return -EIO; + + if (payload_len == 0) + hvs->vsk->peer_shutdown |= SEND_SHUTDOWN; + + hvs->recv_data_len = payload_len; + hvs->recv_data_off = 0; + + return 0; +} + +static ssize_t hvs_stream_dequeue(struct vsock_sock *vsk, struct msghdr *msg, + size_t len, int flags) +{ + struct hvsock *hvs = vsk->trans; + bool need_refill = !hvs->recv_desc; + struct hvs_recv_buf *recv_buf; + u32 to_read; + int ret; + + if (flags & MSG_PEEK) + return -EOPNOTSUPP; + + if (need_refill) { + hvs->recv_desc = hv_pkt_iter_first(hvs->chan); + if (!hvs->recv_desc) + return -ENOBUFS; + ret = hvs_update_recv_data(hvs); + if (ret) + return ret; + } + + recv_buf = (struct hvs_recv_buf *)(hvs->recv_desc + 1); + to_read = min_t(u32, len, hvs->recv_data_len); + ret = memcpy_to_msg(msg, recv_buf->data + hvs->recv_data_off, to_read); + if (ret != 0) + return ret; + + hvs->recv_data_len -= to_read; + if (hvs->recv_data_len == 0) { + hvs->recv_desc = hv_pkt_iter_next(hvs->chan, hvs->recv_desc); + if (hvs->recv_desc) { + ret = hvs_update_recv_data(hvs); + if (ret) + return ret; + } + } else { + hvs->recv_data_off += to_read; + } + + return to_read; +} + +static ssize_t hvs_stream_enqueue(struct vsock_sock *vsk, struct msghdr *msg, + size_t len) +{ + struct hvsock *hvs = vsk->trans; + struct vmbus_channel *chan = hvs->chan; + struct hvs_send_buf *send_buf; + ssize_t to_write, max_writable; + ssize_t ret = 0; + ssize_t bytes_written = 0; + + BUILD_BUG_ON(sizeof(*send_buf) != HV_HYP_PAGE_SIZE); + + send_buf = kmalloc(sizeof(*send_buf), GFP_KERNEL); + if (!send_buf) + return -ENOMEM; + + /* Reader(s) could be draining data from the channel as we write. + * Maximize bandwidth, by iterating until the channel is found to be + * full. + */ + while (len) { + max_writable = hvs_channel_writable_bytes(chan); + if (!max_writable) + break; + to_write = min_t(ssize_t, len, max_writable); + to_write = min_t(ssize_t, to_write, HVS_SEND_BUF_SIZE); + /* memcpy_from_msg is safe for loop as it advances the offsets + * within the message iterator. + */ + ret = memcpy_from_msg(send_buf->data, msg, to_write); + if (ret < 0) + goto out; + + ret = hvs_send_data(hvs->chan, send_buf, to_write); + if (ret < 0) + goto out; + + bytes_written += to_write; + len -= to_write; + } +out: + /* If any data has been sent, return that */ + if (bytes_written) + ret = bytes_written; + kfree(send_buf); + return ret; +} + +static s64 hvs_stream_has_data(struct vsock_sock *vsk) +{ + struct hvsock *hvs = vsk->trans; + s64 ret; + + if (hvs->recv_data_len > 0) + return 1; + + switch (hvs_channel_readable_payload(hvs->chan)) { + case 1: + ret = 1; + break; + case 0: + vsk->peer_shutdown |= SEND_SHUTDOWN; + ret = 0; + break; + default: /* -1 */ + ret = 0; + break; + } + + return ret; +} + +static s64 hvs_stream_has_space(struct vsock_sock *vsk) +{ + struct hvsock *hvs = vsk->trans; + + return hvs_channel_writable_bytes(hvs->chan); +} + +static u64 hvs_stream_rcvhiwat(struct vsock_sock *vsk) +{ + return HVS_MTU_SIZE + 1; +} + +static bool hvs_stream_is_active(struct vsock_sock *vsk) +{ + struct hvsock *hvs = vsk->trans; + + return hvs->chan != NULL; +} + +static bool hvs_stream_allow(u32 cid, u32 port) +{ + if (cid == VMADDR_CID_HOST) + return true; + + return false; +} + +static +int hvs_notify_poll_in(struct vsock_sock *vsk, size_t target, bool *readable) +{ + struct hvsock *hvs = vsk->trans; + + *readable = hvs_channel_readable(hvs->chan); + return 0; +} + +static +int hvs_notify_poll_out(struct vsock_sock *vsk, size_t target, bool *writable) +{ + *writable = hvs_stream_has_space(vsk) > 0; + + return 0; +} + +static +int hvs_notify_recv_init(struct vsock_sock *vsk, size_t target, + struct vsock_transport_recv_notify_data *d) +{ + return 0; +} + +static +int hvs_notify_recv_pre_block(struct vsock_sock *vsk, size_t target, + struct vsock_transport_recv_notify_data *d) +{ + return 0; +} + +static +int hvs_notify_recv_pre_dequeue(struct vsock_sock *vsk, size_t target, + struct vsock_transport_recv_notify_data *d) +{ + return 0; +} + +static +int hvs_notify_recv_post_dequeue(struct vsock_sock *vsk, size_t target, + ssize_t copied, bool data_read, + struct vsock_transport_recv_notify_data *d) +{ + return 0; +} + +static +int hvs_notify_send_init(struct vsock_sock *vsk, + struct vsock_transport_send_notify_data *d) +{ + return 0; +} + +static +int hvs_notify_send_pre_block(struct vsock_sock *vsk, + struct vsock_transport_send_notify_data *d) +{ + return 0; +} + +static +int hvs_notify_send_pre_enqueue(struct vsock_sock *vsk, + struct vsock_transport_send_notify_data *d) +{ + return 0; +} + +static +int hvs_notify_send_post_enqueue(struct vsock_sock *vsk, ssize_t written, + struct vsock_transport_send_notify_data *d) +{ + return 0; +} + +static +int hvs_set_rcvlowat(struct vsock_sock *vsk, int val) +{ + return -EOPNOTSUPP; +} + +static struct vsock_transport hvs_transport = { + .module = THIS_MODULE, + + .get_local_cid = hvs_get_local_cid, + + .init = hvs_sock_init, + .destruct = hvs_destruct, + .release = hvs_release, + .connect = hvs_connect, + .shutdown = hvs_shutdown, + + .dgram_bind = hvs_dgram_bind, + .dgram_dequeue = hvs_dgram_dequeue, + .dgram_enqueue = hvs_dgram_enqueue, + .dgram_allow = hvs_dgram_allow, + + .stream_dequeue = hvs_stream_dequeue, + .stream_enqueue = hvs_stream_enqueue, + .stream_has_data = hvs_stream_has_data, + .stream_has_space = hvs_stream_has_space, + .stream_rcvhiwat = hvs_stream_rcvhiwat, + .stream_is_active = hvs_stream_is_active, + .stream_allow = hvs_stream_allow, + + .notify_poll_in = hvs_notify_poll_in, + .notify_poll_out = hvs_notify_poll_out, + .notify_recv_init = hvs_notify_recv_init, + .notify_recv_pre_block = hvs_notify_recv_pre_block, + .notify_recv_pre_dequeue = hvs_notify_recv_pre_dequeue, + .notify_recv_post_dequeue = hvs_notify_recv_post_dequeue, + .notify_send_init = hvs_notify_send_init, + .notify_send_pre_block = hvs_notify_send_pre_block, + .notify_send_pre_enqueue = hvs_notify_send_pre_enqueue, + .notify_send_post_enqueue = hvs_notify_send_post_enqueue, + + .set_rcvlowat = hvs_set_rcvlowat +}; + +static bool hvs_check_transport(struct vsock_sock *vsk) +{ + return vsk->transport == &hvs_transport; +} + +static int hvs_probe(struct hv_device *hdev, + const struct hv_vmbus_device_id *dev_id) +{ + struct vmbus_channel *chan = hdev->channel; + + hvs_open_connection(chan); + + /* Always return success to suppress the unnecessary error message + * in vmbus_probe(): on error the host will rescind the device in + * 30 seconds and we can do cleanup at that time in + * vmbus_onoffer_rescind(). + */ + return 0; +} + +static int hvs_remove(struct hv_device *hdev) +{ + struct vmbus_channel *chan = hdev->channel; + + vmbus_close(chan); + + return 0; +} + +/* hv_sock connections can not persist across hibernation, and all the hv_sock + * channels are forced to be rescinded before hibernation: see + * vmbus_bus_suspend(). Here the dummy hvs_suspend() and hvs_resume() + * are only needed because hibernation requires that every vmbus device's + * driver should have a .suspend and .resume callback: see vmbus_suspend(). + */ +static int hvs_suspend(struct hv_device *hv_dev) +{ + /* Dummy */ + return 0; +} + +static int hvs_resume(struct hv_device *dev) +{ + /* Dummy */ + return 0; +} + +/* This isn't really used. See vmbus_match() and vmbus_probe() */ +static const struct hv_vmbus_device_id id_table[] = { + {}, +}; + +static struct hv_driver hvs_drv = { + .name = "hv_sock", + .hvsock = true, + .id_table = id_table, + .probe = hvs_probe, + .remove = hvs_remove, + .suspend = hvs_suspend, + .resume = hvs_resume, +}; + +static int __init hvs_init(void) +{ + int ret; + + if (vmbus_proto_version < VERSION_WIN10) + return -ENODEV; + + ret = vmbus_driver_register(&hvs_drv); + if (ret != 0) + return ret; + + ret = vsock_core_register(&hvs_transport, VSOCK_TRANSPORT_F_G2H); + if (ret) { + vmbus_driver_unregister(&hvs_drv); + return ret; + } + + return 0; +} + +static void __exit hvs_exit(void) +{ + vsock_core_unregister(&hvs_transport); + vmbus_driver_unregister(&hvs_drv); +} + +module_init(hvs_init); +module_exit(hvs_exit); + +MODULE_DESCRIPTION("Hyper-V Sockets"); +MODULE_VERSION("1.0.0"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_NETPROTO(PF_VSOCK); -- cgit v1.2.3