Hi Akihiko, On Fri, Feb 25, 2022 at 8:46 PM Akihiko Odaki <akihiko.od...@gmail.com> wrote:
> On 2022/02/26 2:13, Vladislav Yaroshchuk wrote: > > Interaction with vmnet.framework in different modes > > differs only on configuration stage, so we can create > > common `send`, `receive`, etc. procedures and reuse them. > > > > 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 enough performance having .receive() > > net/vmnet: implement shared mode (vmnet-shared) > > > > Interaction with vmnet.framework in different modes > > differs only on configuration stage, so we can create > > common `send`, `receive`, etc. procedures and reuse them. > > > > 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 enough performance having .receive() > > implemented only. > > > > Also, there is no way to unsubscribe from vmnet packages > > receiving except registering and unregistering event > > callback or simply drop packages just ignoring and > > not processing them when related flag is set. Here we do > > using the second way. > > > > Signed-off-by: Phillip Tennen <phil...@axleos.com> > > Signed-off-by: Vladislav Yaroshchuk <vladislav.yaroshc...@jetbrains.com> > > Thank you for persistently working on this. > > > --- > > net/vmnet-common.m | 302 +++++++++++++++++++++++++++++++++++++++++++++ > > net/vmnet-shared.c | 94 +++++++++++++- > > net/vmnet_int.h | 39 +++++- > > 3 files changed, 430 insertions(+), 5 deletions(-) > > > > diff --git a/net/vmnet-common.m b/net/vmnet-common.m > > index 56612c72ce..2f70921cae 100644 > > --- a/net/vmnet-common.m > > +++ b/net/vmnet-common.m > > @@ -10,6 +10,8 @@ > > */ > > > > #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" > > @@ -17,4 +19,304 @@ > > #include "qapi/error.h" > > > > #include <vmnet/vmnet.h> > > +#include <dispatch/dispatch.h> > > > > + > > +static inline void vmnet_set_send_bh_scheduled(VmnetCommonState *s, > > + bool enable) > > +{ > > + qatomic_set(&s->send_scheduled, enable); > > +} > > + > > + > > +static inline bool vmnet_is_send_bh_scheduled(VmnetCommonState *s) > > +{ > > + return qatomic_load_acquire(&s->send_scheduled); > > +} > > + > > + > > +static inline void vmnet_set_send_enabled(VmnetCommonState *s, > > + bool enable) > > +{ > > + if (enable) { > > + 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. > > + * > > + * Avoid scheduling multiple bottom halves > > + */ > > + if (!vmnet_is_send_bh_scheduled(s)) { > > + vmnet_set_send_bh_scheduled(s, true); > > It can be interrupted between vmnet_is_send_bh_scheduled and > vmnet_set_send_bh_scheduled, which leads to data race. > > Sorry, I did not clearly understand what you meant. Since this callback (block) is submitted on DISPATCH_QUEUE_SERIAL, only one instance of the callback will be executed at any moment of time. https://developer.apple.com/documentation/dispatch/dispatch_queue_serial Also this is the only place where we schedule a bottom half. After we set the 'send_scheduled' flag, all the other callback blocks will do nothing (skip the if block) until the bottom half is executed and reset 'send_scheduled'. I don't see any races here :( Correct me if I'm wrong please. > > + qemu_bh_schedule(s->send_bh); > > + } > > + }); > > + } else { > > + vmnet_interface_set_event_callback( > > + s->vmnet_if, > > + VMNET_INTERFACE_PACKETS_AVAILABLE, > > + NULL, > > + NULL); > > + } > > +} > > + > > + > > +static void vmnet_send_completed(NetClientState *nc, ssize_t len) > > +{ > > + VmnetCommonState *s = DO_UPCAST(VmnetCommonState, nc, nc); > > + vmnet_set_send_enabled(s, true); > > +} > > + > > + > > +static void vmnet_send_bh(void *opaque) > > +{ > > + NetClientState *nc = (NetClientState *) opaque; > > + VmnetCommonState *s = DO_UPCAST(VmnetCommonState, nc, nc); > > + > > + struct iovec *iov = s->iov_buf; > > + struct vmpktdesc *packets = s->packets_buf; > > + int pkt_cnt; > > + int i; > > + > > + vmnet_return_t status; > > + ssize_t size; > > + > > + /* read as many packets as present */ > > + pkt_cnt = VMNET_PACKETS_LIMIT; > > There could be more than VMNET_PACKETS_LIMIT. You may call vmnet_read in > a loop. > > > + for (i = 0; i < pkt_cnt; ++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, &pkt_cnt); > > + if (status != VMNET_SUCCESS) { > > + error_printf("vmnet: read failed: %s\n", > > + vmnet_status_map_str(status)); > > + goto done; > > + } > > + > > + for (i = 0; i < pkt_cnt; ++i) { > > + size = qemu_send_packet_async(nc, > > + iov[i].iov_base, > > + packets[i].vm_pkt_size, > > + vmnet_send_completed); > > + if (size == 0) { > > + vmnet_set_send_enabled(s, false); > > + goto done; > > + } else if (size < 0) { > > + break; > > + } > > goto is not needed here. "break" when size <= 0. > > > + } > > + > > +done: > > + vmnet_set_send_bh_scheduled(s, false); > > +} > > + > > + > > +static void vmnet_bufs_init(VmnetCommonState *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; > > + } > > +} > > + > > + > > +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"; > > + } > > +} > > + > > + > > +int vmnet_if_create(NetClientState *nc, > > + xpc_object_t if_desc, > > + Error **errp) > > +{ > > + VmnetCommonState *s = DO_UPCAST(VmnetCommonState, nc, nc);; > > Duplicate semicolons. > > > + dispatch_semaphore_t if_created_sem = dispatch_semaphore_create(0); > > if_created_sem leaks. > > > + __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) { > > + error_setg(errp, > > + "unable to create interface " > > + "with requested params"); > > You don't need line breaks here. Breaking a string into a few would also > makes it a bit hard to grep. > > > + return -1; > > s->if_queue leaks. > > > + } > > + > > + dispatch_semaphore_wait(if_created_sem, DISPATCH_TIME_FOREVER); > > + > > + if (if_status != VMNET_SUCCESS) { > > + 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); > > + vmnet_set_send_bh_scheduled(s, false); > > + vmnet_set_send_enabled(s, true); > > + return 0; > > +} > > + > > + > > +ssize_t vmnet_receive_common(NetClientState *nc, > > + const uint8_t *buf, > > + size_t size) > > +{ > > + VmnetCommonState *s = DO_UPCAST(VmnetCommonState, 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 > %llu\n", > > Use 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)); > > Why don't return -1? > > > + } > > + > > + if (if_status == VMNET_SUCCESS && pkt_cnt) { > > + return size; > > + } > > + return 0; > > +} > > + > > + > > +void vmnet_cleanup_common(NetClientState *nc) > > +{ > > + VmnetCommonState *s = DO_UPCAST(VmnetCommonState, nc, nc);; > > Duplicate semicolons. > > > + dispatch_semaphore_t if_created_sem; > > + > > + qemu_purge_queued_packets(nc); > + > vmnet_set_send_bh_scheduled(s, true); > > + vmnet_set_send_enabled(s, false); > > + > > + if (s->vmnet_if == NULL) { > > + return; > > + } > > + > > + if_created_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_created_sem); > > + }); > > + dispatch_semaphore_wait(if_created_sem, DISPATCH_TIME_FOREVER); > > + > > + qemu_bh_delete(s->send_bh); > > + dispatch_release(if_created_sem); > > + dispatch_release(s->if_queue); > > + > > + for (int i = 0; i < VMNET_PACKETS_LIMIT; ++i) { > > + g_free(s->iov_buf[i].iov_base); > > + } > > +} > > diff --git a/net/vmnet-shared.c b/net/vmnet-shared.c > > index f07afaaf21..66f66c034b 100644 > > --- a/net/vmnet-shared.c > > +++ b/net/vmnet-shared.c > > @@ -10,16 +10,102 @@ > > > > #include "qemu/osdep.h" > > #include "qapi/qapi-types-net.h" > > +#include "qapi/error.h" > > #include "vmnet_int.h" > > #include "clients.h" > > -#include "qemu/error-report.h" > > -#include "qapi/error.h" > > > > #include <vmnet/vmnet.h> > > > > +typedef struct VmnetSharedState { > > + VmnetCommonState cs; > > +} VmnetSharedState; > > + > > + > > +static bool validate_options(const Netdev *netdev, Error **errp) > > +{ > > + const NetdevVmnetSharedOptions *options = &(netdev->u.vmnet_shared); > > + > > +#if !defined(MAC_OS_VERSION_11_0) || \ > > + MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_VERSION_11_0 > > + if (options->has_isolated) { > > + error_setg(errp, > > + "vmnet-shared.isolated feature is " > > + "unavailable: outdated vmnet.framework API"); > > + return false; > > + } > > +#endif > > + > > + if ((options->has_start_address || > > + options->has_end_address || > > + options->has_subnet_mask) && > > + !(options->has_start_address && > > + options->has_end_address && > > + options->has_subnet_mask)) { > > + error_setg(errp, > > + "'start-address', 'end-address', 'subnet-mask' " > > + "should be provided together" > > + ); > > + return false; > > + } > > + > > + return true; > > +} > > + > > +static xpc_object_t build_if_desc(const Netdev *netdev) > > +{ > > + const NetdevVmnetSharedOptions *options = &(netdev->u.vmnet_shared); > > + xpc_object_t if_desc = xpc_dictionary_create(NULL, NULL, 0); > > + > > + xpc_dictionary_set_uint64( > > + if_desc, > > + vmnet_operation_mode_key, > > + VMNET_SHARED_MODE > > + ); > > + > > + if (options->has_nat66_prefix) { > > + xpc_dictionary_set_string(if_desc, > > + vmnet_nat66_prefix_key, > > + options->nat66_prefix); > > + } > > + > > + if (options->has_start_address) { > > + xpc_dictionary_set_string(if_desc, > > + vmnet_start_address_key, > > + options->start_address); > > + xpc_dictionary_set_string(if_desc, > > + vmnet_end_address_key, > > + options->end_address); > > + xpc_dictionary_set_string(if_desc, > > + vmnet_subnet_mask_key, > > + options->subnet_mask); > > + } > > + > > +#if defined(MAC_OS_VERSION_11_0) && \ > > + MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_VERSION_11_0 > > + xpc_dictionary_set_bool( > > + if_desc, > > + vmnet_enable_isolation_key, > > + options->isolated > > + ); > > +#endif > > + > > + return if_desc; > > +} > > + > > +static NetClientInfo net_vmnet_shared_info = { > > + .type = NET_CLIENT_DRIVER_VMNET_SHARED, > > + .size = sizeof(VmnetSharedState), > > + .receive = vmnet_receive_common, > > + .cleanup = vmnet_cleanup_common, > > +}; > > + > > int net_init_vmnet_shared(const Netdev *netdev, const char *name, > > NetClientState *peer, Error **errp) > > { > > - error_setg(errp, "vmnet-shared is not implemented yet"); > > - return -1; > > + NetClientState *nc = qemu_new_net_client(&net_vmnet_shared_info, > > + peer, "vmnet-shared", > name); > > + if (!validate_options(netdev, errp)) { > > + g_assert_not_reached(); > > g_assert_not_reached is for debugging purpose and may be dropped > depending on the build option. > > > + } > > + return vmnet_if_create(nc, build_if_desc(netdev), errp); > > } > > diff --git a/net/vmnet_int.h b/net/vmnet_int.h > > index aac4d5af64..acfe3a88c0 100644 > > --- a/net/vmnet_int.h > > +++ b/net/vmnet_int.h > > @@ -15,11 +15,48 @@ > > #include "clients.h" > > > > #include <vmnet/vmnet.h> > > +#include <dispatch/dispatch.h> > > + > > +/** > > + * From vmnet.framework documentation > > + * > > + * Each read/write call allows up to 200 packets to be > > + * read or written for a maximum of 256KB. > > + * > > + * Each packet written should be a complete > > + * ethernet frame. > > + * > > + * https://developer.apple.com/documentation/vmnet > > + */ > > +#define VMNET_PACKETS_LIMIT 200 > > > > typedef struct VmnetCommonState { > > - NetClientState nc; > > + NetClientState nc; > > + interface_ref vmnet_if; > > + > > + bool send_scheduled; > > > > + uint64_t mtu; > > + uint64_t max_packet_size; > > + > > + struct vmpktdesc packets_buf[VMNET_PACKETS_LIMIT]; > > + struct iovec iov_buf[VMNET_PACKETS_LIMIT]; > > + > > + dispatch_queue_t if_queue; > > + > > + QEMUBH *send_bh; > > } VmnetCommonState; > > > > +const char *vmnet_status_map_str(vmnet_return_t status); > > + > > +int vmnet_if_create(NetClientState *nc, > > + xpc_object_t if_desc, > > + Error **errp); > > + > > +ssize_t vmnet_receive_common(NetClientState *nc, > > + const uint8_t *buf, > > + size_t size); > > + > > +void vmnet_cleanup_common(NetClientState *nc); > > > > #endif /* VMNET_INT_H */ > > Other issues will be fixed and submitted later, thank you! Regards, Vladislav Yaroshchuk