/*
* vmnet-common.m - network client wrapper for Apple vmnet.framework
*
* Copyright(c) 2022 Vladislav Yaroshchuk <vladislav.yaroshchuk@jetbrains.com>
* Copyright(c) 2021 Phillip Tennen <phillip@axleos.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qemu/main-loop.h"
#include "qemu/log.h"
#include "qapi/qapi-types-net.h"
#include "vmnet_int.h"
#include "clients.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include <vmnet/vmnet.h>
#include <dispatch/dispatch.h>
static void vmnet_send_completed(NetClientState *nc, ssize_t len);
const char *vmnet_status_map_str(vmnet_return_t status)
{
switch (status) {
case VMNET_SUCCESS:
return "success";
case VMNET_FAILURE:
return "general failure (possibly not enough privileges)";
case VMNET_MEM_FAILURE:
return "memory allocation failure";
case VMNET_INVALID_ARGUMENT:
return "invalid argument specified";
case VMNET_SETUP_INCOMPLETE:
return "interface setup is not complete";
case VMNET_INVALID_ACCESS:
return "invalid access, permission denied";
case VMNET_PACKET_TOO_BIG:
return "packet size is larger than MTU";
case VMNET_BUFFER_EXHAUSTED:
return "buffers exhausted in kernel";
case VMNET_TOO_MANY_PACKETS:
return "packet count exceeds limit";
#if defined(MAC_OS_VERSION_11_0) && \
MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_VERSION_11_0
case VMNET_SHARING_SERVICE_BUSY:
return "conflict, sharing service is in use";
#endif
default:
return "unknown vmnet error";
}
}
/**
* Write packets from QEMU to vmnet interface.
*
* vmnet.framework supports iov, but writing more than
* one iov into vmnet interface fails with
* 'VMNET_INVALID_ARGUMENT'. Collecting provided iovs into
* one and passing it to vmnet works fine. That's the
* reason why receive_iov() left unimplemented. But it still
* works with good performance having .receive() only.
*/
ssize_t vmnet_receive_common(NetClientState *nc,
const uint8_t *buf,
size_t size)
{
VmnetState *s = DO_UPCAST(VmnetState, nc, nc);
struct vmpktdesc packet;
struct iovec iov;
int pkt_cnt;
vmnet_return_t if_status;
if (size > s->max_packet_size) {
warn_report("vmnet: packet is too big, %zu > %" PRIu64,
packet.vm_pkt_size,
s->max_packet_size);
return -1;
}
iov.iov_base = (char *) buf;
iov.iov_len = size;
packet.vm_pkt_iovcnt = 1;
packet.vm_flags = 0;
packet.vm_pkt_size = size;
packet.vm_pkt_iov = &iov;
pkt_cnt = 1;
if_status = vmnet_write(s->vmnet_if, &packet, &pkt_cnt);
if (if_status != VMNET_SUCCESS) {
error_report("vmnet: write error: %s\n",
vmnet_status_map_str(if_status));
return -1;
}
if (pkt_cnt) {
return size;
}
return 0;
}
/**
* Read packets from vmnet interface and write them
* to temporary buffers in VmnetState.
*
* Returns read packets number (may be 0) on success,
* -1 on error
*/
static int vmnet_read_packets(VmnetState *s)
{
assert(s->packets_send_current_pos == s->packets_send_end_pos);
struct vmpktdesc *packets = s->packets_buf;
vmnet_return_t status;
int i;
/* Read as many packets as present */
s->packets_send_current_pos = 0;
s->packets_send_end_pos = VMNET_PACKETS_LIMIT;
for (i = 0; i < s->packets_send_end_pos; ++i) {
packets[i].vm_pkt_size = s->max_packet_size;
packets[i].vm_pkt_iovcnt = 1;
packets[i].vm_flags = 0;
}
status = vmnet_read(s->vmnet_if, packets, &s->packets_send_end_pos);
if (status != VMNET_SUCCESS) {
error_printf("vmnet: read failed: %s\n",
vmnet_status_map_str(status));
s->packets_send_current_pos = 0;
s->packets_send_end_pos = 0;
return -1;
}
return s->packets_send_end_pos;
}
/**
* Write packets from temporary buffers in VmnetState
* to QEMU.
*/
static void vmnet_write_packets_to_qemu(VmnetState *s)
{
while (s->packets_send_current_pos < s->packets_send_end_pos) {
ssize_t size = qemu_send_packet_async(&s->nc,
s->iov_buf[s->packets_send_current_pos].iov_base,
s->packets_buf[s->packets_send_current_pos].vm_pkt_size,
vmnet_send_completed);
if (size == 0) {
/* QEMU is not ready to consume more packets -
* stop and wait for completion callback call */
return;
}
++s->packets_send_current_pos;
}
}
/**
* Bottom half callback that transfers packets from vmnet interface
* to QEMU.
*
* The process of transferring packets is three-staged:
* 1. Handle vmnet event;
* 2. Read packets from vmnet interface into temporary buffer;
* 3. Write packets from temporary buffer to QEMU.
*
* QEMU may suspend this process on the last stage, returning 0 from
* qemu_send_packet_async function. If this happens, we should
* respectfully wait until it is ready to consume more packets,
* write left ones in temporary buffer and only after this
* continue reading more packets from vmnet interface.
*
* Packets to be transferred are stored into packets_buf,
* in the window [packets_send_current_pos..packets_send_end_pos)
* including current_pos, excluding end_pos.
*
* Thus, if QEMU is not ready, buffer is not read and
* packets_send_current_pos < packets_send_end_pos.
*/
static void vmnet_send_bh(void *opaque)
{
NetClientState *nc = (NetClientState *) opaque;
VmnetState *s = DO_UPCAST(VmnetState, nc, nc);
/*
* Do nothing if QEMU is not ready - wait
* for completion callback invocation
*/
if (s->packets_send_current_pos < s->packets_send_end_pos) {
return;
}
/* Read packets from vmnet interface */
if (vmnet_read_packets(s) > 0) {
/* Send them to QEMU */
vmnet_write_packets_to_qemu(s);
}
}
/**
* Completion callback to be invoked by QEMU when it becomes
* ready to consume more packets.
*/
static void vmnet_send_completed(NetClientState *nc, ssize_t len)
{
VmnetState *s = DO_UPCAST(VmnetState, nc, nc);
/* Callback is invoked eq queued packet is sent */
++s->packets_send_current_pos;
/* Complete sending packets left in VmnetState buffers */
vmnet_write_packets_to_qemu(s);
/* And read new ones from vmnet if VmnetState buffer is ready */
if (s->packets_send_current_pos < s->packets_send_end_pos) {
qemu_bh_schedule(s->send_bh);
}
}
static void vmnet_bufs_init(VmnetState *s)
{
struct vmpktdesc *packets = s->packets_buf;
struct iovec *iov = s->iov_buf;
int i;
for (i = 0; i < VMNET_PACKETS_LIMIT; ++i) {
iov[i].iov_len = s->max_packet_size;
iov[i].iov_base = g_malloc0(iov[i].iov_len);
packets[i].vm_pkt_iov = iov + i;
}
}
int vmnet_if_create(NetClientState *nc,
xpc_object_t if_desc,
Error **errp)
{
VmnetState *s = DO_UPCAST(VmnetState, nc, nc);
dispatch_semaphore_t if_created_sem = dispatch_semaphore_create(0);
__block vmnet_return_t if_status;
s->if_queue = dispatch_queue_create(
"org.qemu.vmnet.if_queue",
DISPATCH_QUEUE_SERIAL
);
xpc_dictionary_set_bool(
if_desc,
vmnet_allocate_mac_address_key,
false
);
#ifdef DEBUG
qemu_log("vmnet.start.interface_desc:\n");
xpc_dictionary_apply(if_desc,
^bool(const char *k, xpc_object_t v) {
char *desc = xpc_copy_description(v);
qemu_log(" %s=%s\n", k, desc);
free(desc);
return true;
});
#endif /* DEBUG */
s->vmnet_if = vmnet_start_interface(
if_desc,
s->if_queue,
^(vmnet_return_t status, xpc_object_t interface_param) {
if_status = status;
if (status != VMNET_SUCCESS || !interface_param) {
dispatch_semaphore_signal(if_created_sem);
return;
}
#ifdef DEBUG
qemu_log("vmnet.start.interface_param:\n");
xpc_dictionary_apply(interface_param,
^bool(const char *k, xpc_object_t v) {
char *desc = xpc_copy_description(v);
qemu_log(" %s=%s\n", k, desc);
free(desc);
return true;
});
#endif /* DEBUG */
s->mtu = xpc_dictionary_get_uint64(
interface_param,
vmnet_mtu_key);
s->max_packet_size = xpc_dictionary_get_uint64(
interface_param,
vmnet_max_packet_size_key);
dispatch_semaphore_signal(if_created_sem);
});
if (s->vmnet_if == NULL) {
dispatch_release(s->if_queue);
dispatch_release(if_created_sem);
error_setg(errp,
"unable to create interface with requested params");
return -1;
}
dispatch_semaphore_wait(if_created_sem, DISPATCH_TIME_FOREVER);
dispatch_release(if_created_sem);
if (if_status != VMNET_SUCCESS) {
dispatch_release(s->if_queue);
error_setg(errp,
"cannot create vmnet interface: %s",
vmnet_status_map_str(if_status));
return -1;
}
s->send_bh = aio_bh_new(qemu_get_aio_context(), vmnet_send_bh, nc);
vmnet_bufs_init(s);
s->packets_send_current_pos = 0;
s->packets_send_end_pos = 0;
vmnet_interface_set_event_callback(
s->vmnet_if,
VMNET_INTERFACE_PACKETS_AVAILABLE,
s->if_queue,
^(interface_event_t event_id, xpc_object_t event) {
assert(event_id == VMNET_INTERFACE_PACKETS_AVAILABLE);
/*
* This function is being called from a non qemu thread, so
* we only schedule a BH, and do the rest of the io completion
* handling from vmnet_send_bh() which runs in a qemu context.
*/
qemu_bh_schedule(s->send_bh);
});
return 0;
}
void vmnet_cleanup_common(NetClientState *nc)
{
VmnetState *s = DO_UPCAST(VmnetState, nc, nc);
dispatch_semaphore_t if_stopped_sem;
if (s->vmnet_if == NULL) {
return;
}
if_stopped_sem = dispatch_semaphore_create(0);
vmnet_stop_interface(
s->vmnet_if,
s->if_queue,
^(vmnet_return_t status) {
assert(status == VMNET_SUCCESS);
dispatch_semaphore_signal(if_stopped_sem);
});
dispatch_semaphore_wait(if_stopped_sem, DISPATCH_TIME_FOREVER);
qemu_purge_queued_packets(nc);
qemu_bh_delete(s->send_bh);
dispatch_release(if_stopped_sem);
dispatch_release(s->if_queue);
for (int i = 0; i < VMNET_PACKETS_LIMIT; ++i) {
g_free(s->iov_buf[i].iov_base);
}
}
