A quick check by checkpatch.pl, pretty straightforward to fix.
ERROR: return is not a function, parentheses are not required
#211: FILE: hw/misc/ivshmem2.c:138:
+ return (ivs->features & (1 << feature));
ERROR: memory barrier without comment
#255: FILE: hw/misc/ivshmem2.c:182:
+ smp_mb();
ERROR: braces {} are necessary for all arms of this statement
#626: FILE: hw/misc/ivshmem2.c:553:
+ if (msg->vector == 0)
[...]
Best,
Liang
On 1/7/20 9:36 AM, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kis...@siemens.com>
>
> This adds a reimplementation of ivshmem in its new revision 2 as
> separate device. The goal of this is not to enable sharing with v1,
> rather to allow explore the properties and potential limitation of the
> new version prior to discussing its integration with the existing code.
>
> v2 always requires a server to interconnect two more more QEMU
> instances because it provides signaling between peers unconditionally.
> Therefore, only the interconnecting chardev, master mode, and the usage
> of ioeventfd can be configured at device level. All other parameters are
> defined by the server instance.
>
> A new server protocol is introduced along this. Its primary difference
> is the introduction of a single welcome message that contains all peer
> parameters, rather than a series of single-word messages pushing them
> piece by piece.
>
> A complicating difference in interrupt handling, compare to v1, is the
> auto-disable mode of v2: When this is active, interrupt delivery is
> disabled by the device after each interrupt event. This prevents the
> usage of irqfd on the receiving side, but it lowers the handling cost
> for guests that implemented interrupt throttling this way (specifically
> when exposing the device via UIO).
>
> No changes have been made to the ivshmem device regarding migration:
> Only the master can live-migrate, slave peers have to hot-unplug the
> device first.
>
> The details of the device model will be specified in a succeeding
> commit. Drivers for this device can currently be found under
>
> http://git.kiszka.org/?p=linux.git;a=shortlog;h=refs/heads/queues/ivshmem2
>
> To instantiate a ivshmem v2 device, just add
>
> ... -chardev socket,path=/tmp/ivshmem_socket,id=ivshmem \
> -device ivshmem,chardev=ivshmem
>
> provided the server opened its socket under the default path.
>
> Signed-off-by: Jan Kiszka <jan.kis...@siemens.com>
> ---
> hw/misc/Makefile.objs | 2 +-
> hw/misc/ivshmem2.c | 1085
> ++++++++++++++++++++++++++++++++++++++++++++
> include/hw/misc/ivshmem2.h | 48 ++
> include/hw/pci/pci_ids.h | 2 +
> 4 files changed, 1136 insertions(+), 1 deletion(-)
> create mode 100644 hw/misc/ivshmem2.c
> create mode 100644 include/hw/misc/ivshmem2.h
>
> diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
> index ba898a5781..90a4a6608c 100644
> --- a/hw/misc/Makefile.objs
> +++ b/hw/misc/Makefile.objs
> @@ -26,7 +26,7 @@ common-obj-$(CONFIG_PUV3) += puv3_pm.o
>
> common-obj-$(CONFIG_MACIO) += macio/
>
> -common-obj-$(CONFIG_IVSHMEM_DEVICE) += ivshmem.o
> +common-obj-$(CONFIG_IVSHMEM_DEVICE) += ivshmem.o ivshmem2.o
>
> common-obj-$(CONFIG_REALVIEW) += arm_sysctl.o
> common-obj-$(CONFIG_NSERIES) += cbus.o
> diff --git a/hw/misc/ivshmem2.c b/hw/misc/ivshmem2.c
> new file mode 100644
> index 0000000000..d5f88ed0e9
> --- /dev/null
> +++ b/hw/misc/ivshmem2.c
> @@ -0,0 +1,1085 @@
> +/*
> + * Inter-VM Shared Memory PCI device, version 2.
> + *
> + * Copyright (c) Siemens AG, 2019
> + *
> + * Authors:
> + * Jan Kiszka <jan.kis...@siemens.com>
> + *
> + * Based on ivshmem.c by Cam Macdonell <c...@cs.ualberta.ca>
> + *
> + * This code is licensed under the GNU GPL v2.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/units.h"
> +#include "qapi/error.h"
> +#include "qemu/cutils.h"
> +#include "hw/hw.h"
> +#include "hw/pci/pci.h"
> +#include "hw/pci/msi.h"
> +#include "hw/pci/msix.h"
> +#include "hw/qdev-properties.h"
> +#include "sysemu/kvm.h"
> +#include "migration/blocker.h"
> +#include "migration/vmstate.h"
> +#include "qemu/error-report.h"
> +#include "qemu/event_notifier.h"
> +#include "qemu/module.h"
> +#include "qom/object_interfaces.h"
> +#include "chardev/char-fe.h"
> +#include "sysemu/qtest.h"
> +#include "qapi/visitor.h"
> +
> +#include "hw/misc/ivshmem2.h"
> +
> +#define PCI_VENDOR_ID_IVSHMEM PCI_VENDOR_ID_SIEMENS
> +#define PCI_DEVICE_ID_IVSHMEM 0x4106
> +
> +#define IVSHMEM_MAX_PEERS UINT16_MAX
> +#define IVSHMEM_IOEVENTFD 0
> +#define IVSHMEM_MSI 1
> +
> +#define IVSHMEM_REG_BAR_SIZE 0x1000
> +
> +#define IVSHMEM_REG_ID 0x00
> +#define IVSHMEM_REG_MAX_PEERS 0x04
> +#define IVSHMEM_REG_INT_CTRL 0x08
> +#define IVSHMEM_REG_DOORBELL 0x0c
> +#define IVSHMEM_REG_STATE 0x10
> +
> +#define IVSHMEM_INT_ENABLE 0x1
> +
> +#define IVSHMEM_ONESHOT_MODE 0x1
> +
> +#define IVSHMEM_DEBUG 0
> +#define IVSHMEM_DPRINTF(fmt, ...) \
> + do { \
> + if (IVSHMEM_DEBUG) { \
> + printf("IVSHMEM: " fmt, ## __VA_ARGS__); \
> + } \
> + } while (0)
> +
> +#define TYPE_IVSHMEM "ivshmem"
> +#define IVSHMEM(obj) \
> + OBJECT_CHECK(IVShmemState, (obj), TYPE_IVSHMEM)
> +
> +typedef struct Peer {
> + int nb_eventfds;
> + EventNotifier *eventfds;
> +} Peer;
> +
> +typedef struct MSIVector {
> + PCIDevice *pdev;
> + int virq;
> + bool unmasked;
> +} MSIVector;
> +
> +typedef struct IVShmemVndrCap {
> + uint8_t id;
> + uint8_t next;
> + uint8_t length;
> + uint8_t priv_ctrl;
> + uint32_t state_tab_sz;
> + uint64_t rw_section_sz;
> + uint64_t output_section_sz;
> +} IVShmemVndrCap;
> +
> +typedef struct IVShmemState {
> + /*< private >*/
> + PCIDevice parent_obj;
> + /*< public >*/
> +
> + uint32_t features;
> +
> + CharBackend server_chr;
> +
> + /* registers */
> + uint8_t *priv_ctrl;
> + uint32_t vm_id;
> + uint32_t intctrl;
> + uint32_t state;
> +
> + /* BARs */
> + MemoryRegion ivshmem_mmio; /* BAR 0 (registers) */
> + MemoryRegion ivshmem_bar2; /* BAR 2 (shared memory) */
> +
> + void *shmem;
> + size_t shmem_sz;
> + size_t output_section_sz;
> +
> + MemoryRegion state_tab;
> + MemoryRegion rw_section;
> + MemoryRegion input_sections;
> + MemoryRegion output_section;
> +
> + /* interrupt support */
> + Peer *peers;
> + int nb_peers; /* space in @peers[] */
> + uint32_t max_peers;
> + uint32_t vectors;
> + MSIVector *msi_vectors;
> +
> + uint8_t msg_buf[32]; /* buffer for receiving server messages */
> + int msg_buffered_bytes; /* #bytes in @msg_buf */
> +
> + uint32_t protocol;
> +
> + /* migration stuff */
> + OnOffAuto master;
> + Error *migration_blocker;
> +} IVShmemState;
> +
> +static void ivshmem_enable_irqfd(IVShmemState *s);
> +static void ivshmem_disable_irqfd(IVShmemState *s);
> +
> +static inline uint32_t ivshmem_has_feature(IVShmemState *ivs,
> + unsigned int feature) {
> + return (ivs->features & (1 << feature));
> +}
> +
> +static inline bool ivshmem_is_master(IVShmemState *s)
> +{
> + assert(s->master != ON_OFF_AUTO_AUTO);
> + return s->master == ON_OFF_AUTO_ON;
> +}
> +
> +static bool ivshmem_irqfd_usable(IVShmemState *s)
> +{
> + PCIDevice *pdev = PCI_DEVICE(s);
> +
> + return (s->intctrl & IVSHMEM_INT_ENABLE) && msix_enabled(pdev) &&
> + !(*s->priv_ctrl & IVSHMEM_ONESHOT_MODE);
> +}
> +
> +static void ivshmem_update_irqfd(IVShmemState *s, bool was_usable)
> +{
> + bool is_usable = ivshmem_irqfd_usable(s);
> +
> + if (kvm_msi_via_irqfd_enabled()) {
> + if (!was_usable && is_usable) {
> + ivshmem_enable_irqfd(s);
> + } else if (was_usable && !is_usable) {
> + ivshmem_disable_irqfd(s);
> + }
> + }
> +}
> +
> +static void ivshmem_write_intctrl(IVShmemState *s, uint32_t new_state)
> +{
> + bool was_usable = ivshmem_irqfd_usable(s);
> +
> + s->intctrl = new_state & IVSHMEM_INT_ENABLE;
> + ivshmem_update_irqfd(s, was_usable);
> +}
> +
> +static void ivshmem_write_state(IVShmemState *s, uint32_t new_state)
> +{
> + uint32_t *state_table = s->shmem;
> + int peer;
> +
> + state_table[s->vm_id] = new_state;
> + smp_mb();
> +
> + if (s->state != new_state) {
> + s->state = new_state;
> + for (peer = 0; peer < s->nb_peers; peer++) {
> + if (peer != s->vm_id && s->peers[peer].nb_eventfds > 0) {
> + event_notifier_set(&s->peers[peer].eventfds[0]);
> + }
> + }
> + }
> +}
> +
> +static void ivshmem_io_write(void *opaque, hwaddr addr,
> + uint64_t val, unsigned size)
> +{
> + IVShmemState *s = opaque;
> +
> + uint16_t dest = val >> 16;
> + uint16_t vector = val & 0xff;
> +
> + addr &= 0xfc;
> +
> + IVSHMEM_DPRINTF("writing to addr " TARGET_FMT_plx "\n", addr);
> + switch (addr) {
> + case IVSHMEM_REG_INT_CTRL:
> + ivshmem_write_intctrl(s, val);
> + break;
> +
> + case IVSHMEM_REG_DOORBELL:
> + /* check that dest VM ID is reasonable */
> + if (dest >= s->nb_peers) {
> + IVSHMEM_DPRINTF("Invalid destination VM ID (%d)\n", dest);
> + break;
> + }
> +
> + /* check doorbell range */
> + if (vector < s->peers[dest].nb_eventfds) {
> + IVSHMEM_DPRINTF("Notifying VM %d on vector %d\n", dest, vector);
> + event_notifier_set(&s->peers[dest].eventfds[vector]);
> + } else {
> + IVSHMEM_DPRINTF("Invalid destination vector %d on VM %d\n",
> + vector, dest);
> + }
> + break;
> +
> + case IVSHMEM_REG_STATE:
> + ivshmem_write_state(s, val);
> + break;
> +
> + default:
> + IVSHMEM_DPRINTF("Unhandled write " TARGET_FMT_plx "\n", addr);
> + }
> +}
> +
> +static uint64_t ivshmem_io_read(void *opaque, hwaddr addr,
> + unsigned size)
> +{
> + IVShmemState *s = opaque;
> + uint32_t ret;
> +
> + switch (addr) {
> + case IVSHMEM_REG_ID:
> + ret = s->vm_id;
> + break;
> +
> + case IVSHMEM_REG_MAX_PEERS:
> + ret = s->max_peers;
> + break;
> +
> + case IVSHMEM_REG_INT_CTRL:
> + ret = s->intctrl;
> + break;
> +
> + case IVSHMEM_REG_STATE:
> + ret = s->state;
> + break;
> +
> + default:
> + IVSHMEM_DPRINTF("why are we reading " TARGET_FMT_plx "\n", addr);
> + ret = 0;
> + }
> +
> + return ret;
> +}
> +
> +static const MemoryRegionOps ivshmem_mmio_ops = {
> + .read = ivshmem_io_read,
> + .write = ivshmem_io_write,
> + .endianness = DEVICE_NATIVE_ENDIAN,
> + .impl = {
> + .min_access_size = 4,
> + .max_access_size = 4,
> + },
> +};
> +
> +static void ivshmem_vector_notify(void *opaque)
> +{
> + MSIVector *entry = opaque;
> + PCIDevice *pdev = entry->pdev;
> + IVShmemState *s = IVSHMEM(pdev);
> + int vector = entry - s->msi_vectors;
> + EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
> +
> + if (!event_notifier_test_and_clear(n) ||
> + !(s->intctrl & IVSHMEM_INT_ENABLE)) {
> + return;
> + }
> +
> + IVSHMEM_DPRINTF("interrupt on vector %p %d\n", pdev, vector);
> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
> + if (msix_enabled(pdev)) {
> + msix_notify(pdev, vector);
> + }
> + } else if (pdev->config[PCI_INTERRUPT_PIN]) {
> + pci_set_irq(pdev, 1);
> + pci_set_irq(pdev, 0);
> + }
> + if (*s->priv_ctrl & IVSHMEM_ONESHOT_MODE) {
> + s->intctrl &= ~IVSHMEM_INT_ENABLE;
> + }
> +}
> +
> +static int ivshmem_irqfd_vector_unmask(PCIDevice *dev, unsigned vector,
> + MSIMessage msg)
> +{
> + IVShmemState *s = IVSHMEM(dev);
> + EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
> + MSIVector *v = &s->msi_vectors[vector];
> + int ret;
> +
> + IVSHMEM_DPRINTF("vector unmask %p %d\n", dev, vector);
> + if (!v->pdev) {
> + error_report("ivshmem: vector %d route does not exist", vector);
> + return -EINVAL;
> + }
> + assert(!v->unmasked);
> +
> + ret = kvm_irqchip_add_msi_route(kvm_state, vector, dev);
> + if (ret < 0) {
> + error_report("kvm_irqchip_add_msi_route failed");
> + return ret;
> + }
> + v->virq = ret;
> + kvm_irqchip_commit_routes(kvm_state);
> +
> + ret = kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, n, NULL, v->virq);
> + if (ret < 0) {
> + error_report("kvm_irqchip_add_irqfd_notifier_gsi failed");
> + return ret;
> + }
> + v->unmasked = true;
> +
> + return 0;
> +}
> +
> +static void ivshmem_irqfd_vector_mask(PCIDevice *dev, unsigned vector)
> +{
> + IVShmemState *s = IVSHMEM(dev);
> + EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
> + MSIVector *v = &s->msi_vectors[vector];
> + int ret;
> +
> + IVSHMEM_DPRINTF("vector mask %p %d\n", dev, vector);
> + if (!v->pdev) {
> + error_report("ivshmem: vector %d route does not exist", vector);
> + return;
> + }
> + assert(v->unmasked);
> +
> + ret = kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, n, v->virq);
> + if (ret < 0) {
> + error_report("remove_irqfd_notifier_gsi failed");
> + return;
> + }
> + kvm_irqchip_release_virq(kvm_state, v->virq);
> +
> + v->unmasked = false;
> +}
> +
> +static void ivshmem_irqfd_vector_poll(PCIDevice *dev,
> + unsigned int vector_start,
> + unsigned int vector_end)
> +{
> + IVShmemState *s = IVSHMEM(dev);
> + unsigned int vector;
> +
> + IVSHMEM_DPRINTF("vector poll %p %d-%d\n", dev, vector_start, vector_end);
> +
> + vector_end = MIN(vector_end, s->vectors);
> +
> + for (vector = vector_start; vector < vector_end; vector++) {
> + EventNotifier *notifier = &s->peers[s->vm_id].eventfds[vector];
> +
> + if (!msix_is_masked(dev, vector)) {
> + continue;
> + }
> +
> + if (event_notifier_test_and_clear(notifier)) {
> + msix_set_pending(dev, vector);
> + }
> + }
> +}
> +
> +static void ivshmem_watch_vector_notifier(IVShmemState *s, int vector)
> +{
> + EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
> + int eventfd = event_notifier_get_fd(n);
> +
> + assert(!s->msi_vectors[vector].pdev);
> + s->msi_vectors[vector].pdev = PCI_DEVICE(s);
> +
> + qemu_set_fd_handler(eventfd, ivshmem_vector_notify,
> + NULL, &s->msi_vectors[vector]);
> +}
> +
> +static void ivshmem_unwatch_vector_notifier(IVShmemState *s, int vector)
> +{
> + EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
> + int eventfd = event_notifier_get_fd(n);
> +
> + if (!s->msi_vectors[vector].pdev) {
> + return;
> + }
> +
> + qemu_set_fd_handler(eventfd, NULL, NULL, NULL);
> +
> + s->msi_vectors[vector].pdev = NULL;
> +}
> +
> +static void ivshmem_add_eventfd(IVShmemState *s, int posn, int i)
> +{
> + memory_region_add_eventfd(&s->ivshmem_mmio,
> + IVSHMEM_REG_DOORBELL,
> + 4,
> + true,
> + (posn << 16) | i,
> + &s->peers[posn].eventfds[i]);
> +}
> +
> +static void ivshmem_del_eventfd(IVShmemState *s, int posn, int i)
> +{
> + memory_region_del_eventfd(&s->ivshmem_mmio,
> + IVSHMEM_REG_DOORBELL,
> + 4,
> + true,
> + (posn << 16) | i,
> + &s->peers[posn].eventfds[i]);
> +}
> +
> +static void close_peer_eventfds(IVShmemState *s, int posn)
> +{
> + int i, n;
> +
> + assert(posn >= 0 && posn < s->nb_peers);
> + n = s->peers[posn].nb_eventfds;
> +
> + if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
> + memory_region_transaction_begin();
> + for (i = 0; i < n; i++) {
> + ivshmem_del_eventfd(s, posn, i);
> + }
> + memory_region_transaction_commit();
> + }
> +
> + for (i = 0; i < n; i++) {
> + event_notifier_cleanup(&s->peers[posn].eventfds[i]);
> + }
> +
> + g_free(s->peers[posn].eventfds);
> + s->peers[posn].nb_eventfds = 0;
> +}
> +
> +static void resize_peers(IVShmemState *s, int nb_peers)
> +{
> + int old_nb_peers = s->nb_peers;
> + int i;
> +
> + assert(nb_peers > old_nb_peers);
> + IVSHMEM_DPRINTF("bumping storage to %d peers\n", nb_peers);
> +
> + s->peers = g_realloc(s->peers, nb_peers * sizeof(Peer));
> + s->nb_peers = nb_peers;
> +
> + for (i = old_nb_peers; i < nb_peers; i++) {
> + s->peers[i].eventfds = NULL;
> + s->peers[i].nb_eventfds = 0;
> + }
> +}
> +
> +static void ivshmem_add_kvm_msi_virq(IVShmemState *s, int vector, Error
> **errp)
> +{
> + PCIDevice *pdev = PCI_DEVICE(s);
> +
> + IVSHMEM_DPRINTF("ivshmem_add_kvm_msi_virq vector:%d\n", vector);
> + assert(!s->msi_vectors[vector].pdev);
> +
> + s->msi_vectors[vector].unmasked = false;
> + s->msi_vectors[vector].pdev = pdev;
> +}
> +
> +static void ivshmem_remove_kvm_msi_virq(IVShmemState *s, int vector)
> +{
> + IVSHMEM_DPRINTF("ivshmem_remove_kvm_msi_virq vector:%d\n", vector);
> +
> + if (s->msi_vectors[vector].pdev == NULL) {
> + return;
> + }
> +
> + if (s->msi_vectors[vector].unmasked) {
> + ivshmem_irqfd_vector_mask(s->msi_vectors[vector].pdev, vector);
> + }
> +
> + s->msi_vectors[vector].pdev = NULL;
> +}
> +
> +static void process_msg_disconnect(IVShmemState *s, IvshmemPeerGone *msg,
> + Error **errp)
> +{
> + if (msg->header.len < sizeof(*msg)) {
> + error_setg(errp, "Invalid peer-gone message size");
> + return;
> + }
> +
> + le32_to_cpus(&msg->id);
> +
> + IVSHMEM_DPRINTF("peer %d has gone away\n", msg->id);
> + if (msg->id >= s->nb_peers || msg->id == s->vm_id) {
> + error_setg(errp, "invalid peer %d", msg->id);
> + return;
> + }
> + close_peer_eventfds(s, msg->id);
> + event_notifier_set(&s->peers[s->vm_id].eventfds[0]);
> +}
> +
> +static void process_msg_connect(IVShmemState *s, IvshmemEventFd *msg, int fd,
> + Error **errp)
> +{
> + Peer *peer;
> +
> + if (msg->header.len < sizeof(*msg)) {
> + error_setg(errp, "Invalid eventfd message size");
> + close(fd);
> + return;
> + }
> +
> + le32_to_cpus(&msg->id);
> + le32_to_cpus(&msg->vector);
> +
> + if (msg->id >= s->nb_peers) {
> + resize_peers(s, msg->id + 1);
> + }
> +
> + peer = &s->peers[msg->id];
> +
> + /*
> + * The N-th connect message for this peer comes with the file
> + * descriptor for vector N-1.
> + */
> + if (msg->vector != peer->nb_eventfds) {
> + error_setg(errp, "Received vector %d out of order", msg->vector);
> + close(fd);
> + return;
> + }
> + if (peer->nb_eventfds >= s->vectors) {
> + error_setg(errp, "Too many eventfd received, device has %d vectors",
> + s->vectors);
> + close(fd);
> + return;
> + }
> + peer->nb_eventfds++;
> +
> + if (msg->vector == 0)
> + peer->eventfds = g_new0(EventNotifier, s->vectors);
> +
> + IVSHMEM_DPRINTF("eventfds[%d][%d] = %d\n", msg->id, msg->vector, fd);
> + event_notifier_init_fd(&peer->eventfds[msg->vector], fd);
> + fcntl_setfl(fd, O_NONBLOCK); /* msix/irqfd poll non block */
> +
> + if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
> + ivshmem_add_eventfd(s, msg->id, msg->vector);
> + }
> +
> + if (msg->id == s->vm_id) {
> + ivshmem_watch_vector_notifier(s, peer->nb_eventfds - 1);
> + }
> +}
> +
> +static int ivshmem_can_receive(void *opaque)
> +{
> + IVShmemState *s = opaque;
> +
> + assert(s->msg_buffered_bytes < sizeof(s->msg_buf));
> + return sizeof(s->msg_buf) - s->msg_buffered_bytes;
> +}
> +
> +static void ivshmem_read(void *opaque, const uint8_t *buf, int size)
> +{
> + IVShmemState *s = opaque;
> + IvshmemMsgHeader *header = (IvshmemMsgHeader *)&s->msg_buf;
> + Error *err = NULL;
> + int fd;
> +
> + assert(size >= 0 && s->msg_buffered_bytes + size <= sizeof(s->msg_buf));
> + memcpy(s->msg_buf + s->msg_buffered_bytes, buf, size);
> + s->msg_buffered_bytes += size;
> + if (s->msg_buffered_bytes < sizeof(*header) ||
> + s->msg_buffered_bytes < le32_to_cpu(header->len)) {
> + return;
> + }
> +
> + fd = qemu_chr_fe_get_msgfd(&s->server_chr);
> +
> + le32_to_cpus(&header->type);
> + le32_to_cpus(&header->len);
> +
> + switch (header->type) {
> + case IVSHMEM_MSG_EVENT_FD:
> + process_msg_connect(s, (IvshmemEventFd *)header, fd, &err);
> + break;
> + case IVSHMEM_MSG_PEER_GONE:
> + process_msg_disconnect(s, (IvshmemPeerGone *)header, &err);
> + break;
> + default:
> + error_setg(&err, "invalid message, type %d", header->type);
> + break;
> + }
> + if (err) {
> + error_report_err(err);
> + }
> +
> + s->msg_buffered_bytes -= header->len;
> + memmove(s->msg_buf, s->msg_buf + header->len, s->msg_buffered_bytes);
> +}
> +
> +static void ivshmem_recv_setup(IVShmemState *s, Error **errp)
> +{
> + IvshmemInitialInfo msg;
> + struct stat buf;
> + uint8_t dummy;
> + int fd, n, ret;
> +
> + n = 0;
> + do {
> + ret = qemu_chr_fe_read_all(&s->server_chr, (uint8_t *)&msg + n,
> + sizeof(msg) - n);
> + if (ret < 0) {
> + if (ret == -EINTR) {
> + continue;
> + }
> + error_setg_errno(errp, -ret, "read from server failed");
> + return;
> + }
> + n += ret;
> + } while (n < sizeof(msg));
> +
> + fd = qemu_chr_fe_get_msgfd(&s->server_chr);
> +
> + le32_to_cpus(&msg.header.type);
> + le32_to_cpus(&msg.header.len);
> + if (msg.header.type != IVSHMEM_MSG_INIT || msg.header.len < sizeof(msg))
> {
> + error_setg(errp, "server sent invalid initial info");
> + return;
> + }
> +
> + /* consume additional bytes of message */
> + msg.header.len -= sizeof(msg);
> + while (msg.header.len > 0) {
> + ret = qemu_chr_fe_read_all(&s->server_chr, &dummy, 1);
> + if (ret < 0) {
> + if (ret == -EINTR) {
> + continue;
> + }
> + error_setg_errno(errp, -ret, "read from server failed");
> + return;
> + }
> + msg.header.len -= ret;
> + }
> +
> + le32_to_cpus(&msg.compatible_version);
> + if (msg.compatible_version != IVSHMEM_PROTOCOL_VERSION) {
> + error_setg(errp, "server sent compatible version %u, expecting %u",
> + msg.compatible_version, IVSHMEM_PROTOCOL_VERSION);
> + return;
> + }
> +
> + le32_to_cpus(&msg.id);
> + if (msg.id > IVSHMEM_MAX_PEERS) {
> + error_setg(errp, "server sent invalid ID");
> + return;
> + }
> + s->vm_id = msg.id;
> +
> + if (fstat(fd, &buf) < 0) {
> + error_setg_errno(errp, errno,
> + "can't determine size of shared memory sent by server");
> + close(fd);
> + return;
> + }
> +
> + s->shmem_sz = buf.st_size;
> +
> + s->shmem = mmap(NULL, s->shmem_sz, PROT_READ | PROT_WRITE, MAP_SHARED,
> + fd, 0);
> + if (s->shmem == MAP_FAILED) {
> + error_setg_errno(errp, errno,
> + "can't map shared memory sent by server");
> + return;
> + }
> +
> + le32_to_cpus(&msg.vectors);
> + if (msg.vectors < 1 || msg.vectors > 1024) {
> + error_setg(errp, "server sent invalid number of vectors message");
> + return;
> + }
> + s->vectors = msg.vectors;
> +
> + s->max_peers = le32_to_cpu(msg.max_peers);
> + s->protocol = le32_to_cpu(msg.protocol);
> + s->output_section_sz = le64_to_cpu(msg.output_section_size);
> +}
> +
> +/* Select the MSI-X vectors used by device.
> + * ivshmem maps events to vectors statically, so
> + * we just enable all vectors on init and after reset. */
> +static void ivshmem_msix_vector_use(IVShmemState *s)
> +{
> + PCIDevice *d = PCI_DEVICE(s);
> + int i;
> +
> + for (i = 0; i < s->vectors; i++) {
> + msix_vector_use(d, i);
> + }
> +}
> +
> +static void ivshmem_reset(DeviceState *d)
> +{
> + IVShmemState *s = IVSHMEM(d);
> +
> + ivshmem_disable_irqfd(s);
> +
> + s->intctrl = 0;
> + ivshmem_write_state(s, 0);
> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
> + ivshmem_msix_vector_use(s);
> + }
> +}
> +
> +static int ivshmem_setup_interrupts(IVShmemState *s, Error **errp)
> +{
> + /* allocate QEMU callback data for receiving interrupts */
> + s->msi_vectors = g_malloc0(s->vectors * sizeof(MSIVector));
> +
> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
> + if (msix_init_exclusive_bar(PCI_DEVICE(s), s->vectors, 1, errp)) {
> + IVSHMEM_DPRINTF("msix requested but not available -
> disabling\n");
> + s->features &= ~(IVSHMEM_MSI | IVSHMEM_IOEVENTFD);
> + } else {
> + IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
> + ivshmem_msix_vector_use(s);
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void ivshmem_enable_irqfd(IVShmemState *s)
> +{
> + PCIDevice *pdev = PCI_DEVICE(s);
> + int i;
> +
> + for (i = 0; i < s->peers[s->vm_id].nb_eventfds; i++) {
> + Error *err = NULL;
> +
> + ivshmem_unwatch_vector_notifier(s, i);
> +
> + ivshmem_add_kvm_msi_virq(s, i, &err);
> + if (err) {
> + error_report_err(err);
> + goto undo;
> + }
> + }
> +
> + if (msix_set_vector_notifiers(pdev,
> + ivshmem_irqfd_vector_unmask,
> + ivshmem_irqfd_vector_mask,
> + ivshmem_irqfd_vector_poll)) {
> + error_report("ivshmem: msix_set_vector_notifiers failed");
> + goto undo;
> + }
> + return;
> +
> +undo:
> + while (--i >= 0) {
> + ivshmem_remove_kvm_msi_virq(s, i);
> + }
> +}
> +
> +static void ivshmem_disable_irqfd(IVShmemState *s)
> +{
> + PCIDevice *pdev = PCI_DEVICE(s);
> + int i;
> +
> + if (!pdev->msix_vector_use_notifier) {
> + return;
> + }
> +
> + msix_unset_vector_notifiers(pdev);
> +
> + for (i = 0; i < s->peers[s->vm_id].nb_eventfds; i++) {
> + ivshmem_remove_kvm_msi_virq(s, i);
> + ivshmem_watch_vector_notifier(s, i);
> + }
> +
> +}
> +
> +static void ivshmem_write_config(PCIDevice *pdev, uint32_t address,
> + uint32_t val, int len)
> +{
> + IVShmemState *s = IVSHMEM(pdev);
> + bool was_usable = ivshmem_irqfd_usable(s);
> +
> + pci_default_write_config(pdev, address, val, len);
> + ivshmem_update_irqfd(s, was_usable);
> +}
> +
> +static void ivshmem_exit(PCIDevice *dev)
> +{
> + IVShmemState *s = IVSHMEM(dev);
> + int i;
> +
> + if (s->migration_blocker) {
> + migrate_del_blocker(s->migration_blocker);
> + error_free(s->migration_blocker);
> + }
> +
> + if (memory_region_is_mapped(&s->rw_section)) {
> + void *addr = memory_region_get_ram_ptr(&s->rw_section);
> + int fd;
> +
> + if (munmap(addr, memory_region_size(&s->rw_section) == -1)) {
> + error_report("Failed to munmap shared memory %s",
> + strerror(errno));
> + }
> +
> + fd = memory_region_get_fd(&s->rw_section);
> + close(fd);
> +
> + vmstate_unregister_ram(&s->state_tab, DEVICE(dev));
> + vmstate_unregister_ram(&s->rw_section, DEVICE(dev));
> + }
> +
> + if (s->peers) {
> + for (i = 0; i < s->nb_peers; i++) {
> + close_peer_eventfds(s, i);
> + }
> + g_free(s->peers);
> + }
> +
> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
> + msix_uninit_exclusive_bar(dev);
> + }
> +
> + g_free(s->msi_vectors);
> +}
> +
> +static int ivshmem_pre_load(void *opaque)
> +{
> + IVShmemState *s = opaque;
> +
> + if (!ivshmem_is_master(s)) {
> + error_report("'peer' devices are not migratable");
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int ivshmem_post_load(void *opaque, int version_id)
> +{
> + IVShmemState *s = opaque;
> +
> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
> + ivshmem_msix_vector_use(s);
> + }
> + return 0;
> +}
> +
> +static const VMStateDescription ivshmem_vmsd = {
> + .name = TYPE_IVSHMEM,
> + .version_id = 0,
> + .minimum_version_id = 0,
> + .pre_load = ivshmem_pre_load,
> + .post_load = ivshmem_post_load,
> + .fields = (VMStateField[]) {
> + VMSTATE_PCI_DEVICE(parent_obj, IVShmemState),
> + VMSTATE_MSIX(parent_obj, IVShmemState),
> + VMSTATE_UINT32(state, IVShmemState),
> + VMSTATE_UINT32(intctrl, IVShmemState),
> + VMSTATE_END_OF_LIST()
> + },
> +};
> +
> +static Property ivshmem_properties[] = {
> + DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
> + DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD,
> + true),
> + DEFINE_PROP_ON_OFF_AUTO("master", IVShmemState, master, ON_OFF_AUTO_OFF),
> + DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void ivshmem_init(Object *obj)
> +{
> + IVShmemState *s = IVSHMEM(obj);
> +
> + s->features |= (1 << IVSHMEM_MSI);
> +}
> +
> +static void ivshmem_realize(PCIDevice *dev, Error **errp)
> +{
> + IVShmemState *s = IVSHMEM(dev);
> + Chardev *chr = qemu_chr_fe_get_driver(&s->server_chr);
> + size_t rw_section_sz, input_sections_sz;
> + IVShmemVndrCap *vndr_cap;
> + Error *err = NULL;
> + uint8_t *pci_conf;
> + int offset, priv_ctrl_pos;
> + off_t shmem_pos;
> +
> + if (!qemu_chr_fe_backend_connected(&s->server_chr)) {
> + error_setg(errp, "You must specify a 'chardev'");
> + return;
> + }
> +
> + /* IRQFD requires MSI */
> + if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
> + !ivshmem_has_feature(s, IVSHMEM_MSI)) {
> + error_setg(errp, "ioeventfd/irqfd requires MSI");
> + return;
> + }
> +
> + pci_conf = dev->config;
> + pci_conf[PCI_COMMAND] = PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
> +
> + memory_region_init_io(&s->ivshmem_mmio, OBJECT(s), &ivshmem_mmio_ops, s,
> + "ivshmem.mmio", IVSHMEM_REG_BAR_SIZE);
> +
> + /* region for registers*/
> + pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY,
> + &s->ivshmem_mmio);
> +
> + assert(chr);
> + IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
> + chr->filename);
> +
> + /*
> + * Receive setup messages from server synchronously.
> + * Older versions did it asynchronously, but that creates a
> + * number of entertaining race conditions.
> + */
> + ivshmem_recv_setup(s, &err);
> + if (err) {
> + error_propagate(errp, err);
> + return;
> + }
> +
> + /* we allocate enough space for 16 peers and grow as needed */
> + resize_peers(s, 16);
> +
> + if (s->master == ON_OFF_AUTO_ON && s->vm_id != 0) {
> + error_setg(errp,
> + "Master must connect to the server before any peers");
> + return;
> + }
> +
> + qemu_chr_fe_set_handlers(&s->server_chr, ivshmem_can_receive,
> + ivshmem_read, NULL, NULL, s, NULL, true);
> +
> + if (ivshmem_setup_interrupts(s, errp) < 0) {
> + error_prepend(errp, "Failed to initialize interrupts: ");
> + return;
> + }
> +
> + memory_region_init(&s->ivshmem_bar2, OBJECT(s), "ivshmem.bar2",
> + s->shmem_sz);
> +
> + input_sections_sz = s->output_section_sz * s->max_peers;
> + if (input_sections_sz + 4096 > s->shmem_sz) {
> + error_setg(errp,
> + "Invalid output section size, shared memory too small");
> + return;
> + }
> + rw_section_sz = s->shmem_sz - input_sections_sz - 4096;
> +
> + shmem_pos = 0;
> + memory_region_init_ram_ptr(&s->state_tab, OBJECT(s), "ivshmem.state",
> + 4096, s->shmem + shmem_pos);
> + memory_region_set_readonly(&s->state_tab, true);
> + memory_region_add_subregion(&s->ivshmem_bar2, shmem_pos, &s->state_tab);
> +
> + vmstate_register_ram(&s->state_tab, DEVICE(s));
> +
> + if (rw_section_sz > 0) {
> + shmem_pos += 4096;
> + memory_region_init_ram_ptr(&s->rw_section, OBJECT(s),
> + "ivshmem.rw-section",
> + rw_section_sz, s->shmem + shmem_pos);
> + memory_region_add_subregion(&s->ivshmem_bar2, shmem_pos,
> + &s->rw_section);
> +
> + vmstate_register_ram(&s->rw_section, DEVICE(s));
> + }
> +
> + if (s->output_section_sz > 0) {
> + shmem_pos += rw_section_sz;
> + memory_region_init_ram_ptr(&s->input_sections, OBJECT(s),
> + "ivshmem.input-sections",
> input_sections_sz,
> + s->shmem + shmem_pos);
> + memory_region_set_readonly(&s->input_sections, true);
> + memory_region_add_subregion(&s->ivshmem_bar2, shmem_pos,
> + &s->input_sections);
> +
> + shmem_pos += s->vm_id * s->output_section_sz;
> + memory_region_init_ram_ptr(&s->output_section, OBJECT(s),
> + "ivshmem.output-section",
> + s->output_section_sz, s->shmem +
> shmem_pos);
> + memory_region_add_subregion_overlap(&s->ivshmem_bar2, shmem_pos,
> + &s->output_section, 1);
> +
> + vmstate_register_ram(&s->input_sections, DEVICE(s));
> + }
> +
> + pci_config_set_class(dev->config, 0xff00 | (s->protocol >> 8));
> + pci_config_set_prog_interface(dev->config, (uint8_t)s->protocol);
> +
> + offset = pci_add_capability(dev, PCI_CAP_ID_VNDR, 0, 0x18,
> + &error_abort);
> + vndr_cap = (IVShmemVndrCap *)(pci_conf + offset);
> + vndr_cap->length = 0x18;
> + vndr_cap->state_tab_sz = cpu_to_le32(4096);
> + vndr_cap->rw_section_sz = cpu_to_le64(rw_section_sz);
> + vndr_cap->output_section_sz = s->output_section_sz;
> +
> + priv_ctrl_pos = offset + offsetof(IVShmemVndrCap, priv_ctrl);
> + s->priv_ctrl = &dev->config[priv_ctrl_pos];
> + dev->wmask[priv_ctrl_pos] |= IVSHMEM_ONESHOT_MODE;
> +
> + if (s->master == ON_OFF_AUTO_AUTO) {
> + s->master = s->vm_id == 0 ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
> + }
> +
> + if (!ivshmem_is_master(s)) {
> + error_setg(&s->migration_blocker,
> + "Migration is disabled when using feature 'peer mode' in
> device 'ivshmem'");
> + migrate_add_blocker(s->migration_blocker, &err);
> + if (err) {
> + error_propagate(errp, err);
> + error_free(s->migration_blocker);
> + return;
> + }
> + }
> +
> + pci_register_bar(PCI_DEVICE(s), 2,
> + PCI_BASE_ADDRESS_SPACE_MEMORY |
> + PCI_BASE_ADDRESS_MEM_PREFETCH |
> + PCI_BASE_ADDRESS_MEM_TYPE_64,
> + &s->ivshmem_bar2);
> +}
> +
> +static void ivshmem_class_init(ObjectClass *klass, void *data)
> +{
> + DeviceClass *dc = DEVICE_CLASS(klass);
> + PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
> +
> + k->realize = ivshmem_realize;
> + k->exit = ivshmem_exit;
> + k->config_write = ivshmem_write_config;
> + k->vendor_id = PCI_VENDOR_ID_IVSHMEM;
> + k->device_id = PCI_DEVICE_ID_IVSHMEM;
> + dc->reset = ivshmem_reset;
> + set_bit(DEVICE_CATEGORY_MISC, dc->categories);
> + dc->desc = "Inter-VM shared memory v2";
> +
> + dc->props = ivshmem_properties;
> + dc->vmsd = &ivshmem_vmsd;
> +}
> +
> +static const TypeInfo ivshmem_info = {
> + .name = TYPE_IVSHMEM,
> + .parent = TYPE_PCI_DEVICE,
> + .instance_size = sizeof(IVShmemState),
> + .instance_init = ivshmem_init,
> + .class_init = ivshmem_class_init,
> + .interfaces = (InterfaceInfo[]) {
> + { INTERFACE_CONVENTIONAL_PCI_DEVICE },
> + { },
> + },
> +};
> +
> +static void ivshmem_register_types(void)
> +{
> + type_register_static(&ivshmem_info);
> +}
> +
> +type_init(ivshmem_register_types)
> diff --git a/include/hw/misc/ivshmem2.h b/include/hw/misc/ivshmem2.h
> new file mode 100644
> index 0000000000..ee994699e8
> --- /dev/null
> +++ b/include/hw/misc/ivshmem2.h
> @@ -0,0 +1,48 @@
> +/*
> + * Inter-VM Shared Memory PCI device, Version 2.
> + *
> + * Copyright (c) Siemens AG, 2019
> + *
> + * Authors:
> + * Jan Kiszka <jan.kis...@siemens.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> + * (at your option) any later version.
> + */
> +#ifndef IVSHMEM2_H
> +#define IVSHMEM2_H
> +
> +#define IVSHMEM_PROTOCOL_VERSION 2
> +
> +#define IVSHMEM_MSG_INIT 0
> +#define IVSHMEM_MSG_EVENT_FD 1
> +#define IVSHMEM_MSG_PEER_GONE 2
> +
> +typedef struct IvshmemMsgHeader {
> + uint32_t type;
> + uint32_t len;
> +} IvshmemMsgHeader;
> +
> +typedef struct IvshmemInitialInfo {
> + IvshmemMsgHeader header;
> + uint32_t version;
> + uint32_t compatible_version;
> + uint32_t id;
> + uint32_t max_peers;
> + uint32_t vectors;
> + uint32_t protocol;
> + uint64_t output_section_size;
> +} IvshmemInitialInfo;
> +
> +typedef struct IvshmemEventFd {
> + IvshmemMsgHeader header;
> + uint32_t id;
> + uint32_t vector;
> +} IvshmemEventFd;
> +
> +typedef struct IvshmemPeerGone {
> + IvshmemMsgHeader header;
> + uint32_t id;
> +} IvshmemPeerGone;
> +
> +#endif /* IVSHMEM2_H */
> diff --git a/include/hw/pci/pci_ids.h b/include/hw/pci/pci_ids.h
> index 11f8ab7149..f0c5d5ed2b 100644
> --- a/include/hw/pci/pci_ids.h
> +++ b/include/hw/pci/pci_ids.h
> @@ -264,6 +264,8 @@
> #define PCI_VENDOR_ID_NEC 0x1033
> #define PCI_DEVICE_ID_NEC_UPD720200 0x0194
>
> +#define PCI_VENDOR_ID_SIEMENS 0x110a
> +
> #define PCI_VENDOR_ID_TEWS 0x1498
> #define PCI_DEVICE_ID_TEWS_TPCI200 0x30C8
>
>
