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-rw-r--r--hw/misc/ivshmem.c1135
1 files changed, 1135 insertions, 0 deletions
diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
new file mode 100644
index 000000000..1ba4a9837
--- /dev/null
+++ b/hw/misc/ivshmem.c
@@ -0,0 +1,1135 @@
+/*
+ * Inter-VM Shared Memory PCI device.
+ *
+ * Author:
+ * Cam Macdonell <cam@cs.ualberta.ca>
+ *
+ * Based On: cirrus_vga.c
+ * Copyright (c) 2004 Fabrice Bellard
+ * Copyright (c) 2004 Makoto Suzuki (suzu)
+ *
+ * and rtl8139.c
+ * Copyright (c) 2006 Igor Kovalenko
+ *
+ * This code is licensed under the GNU GPL v2.
+ *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/units.h"
+#include "qapi/error.h"
+#include "qemu/cutils.h"
+#include "hw/pci/pci.h"
+#include "hw/qdev-properties.h"
+#include "hw/qdev-properties-system.h"
+#include "hw/pci/msi.h"
+#include "hw/pci/msix.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/hostmem.h"
+#include "qapi/visitor.h"
+
+#include "hw/misc/ivshmem.h"
+#include "qom/object.h"
+
+#define PCI_VENDOR_ID_IVSHMEM PCI_VENDOR_ID_REDHAT_QUMRANET
+#define PCI_DEVICE_ID_IVSHMEM 0x1110
+
+#define IVSHMEM_MAX_PEERS UINT16_MAX
+#define IVSHMEM_IOEVENTFD 0
+#define IVSHMEM_MSI 1
+
+#define IVSHMEM_REG_BAR_SIZE 0x100
+
+#define IVSHMEM_DEBUG 0
+#define IVSHMEM_DPRINTF(fmt, ...) \
+ do { \
+ if (IVSHMEM_DEBUG) { \
+ printf("IVSHMEM: " fmt, ## __VA_ARGS__); \
+ } \
+ } while (0)
+
+#define TYPE_IVSHMEM_COMMON "ivshmem-common"
+typedef struct IVShmemState IVShmemState;
+DECLARE_INSTANCE_CHECKER(IVShmemState, IVSHMEM_COMMON,
+ TYPE_IVSHMEM_COMMON)
+
+#define TYPE_IVSHMEM_PLAIN "ivshmem-plain"
+DECLARE_INSTANCE_CHECKER(IVShmemState, IVSHMEM_PLAIN,
+ TYPE_IVSHMEM_PLAIN)
+
+#define TYPE_IVSHMEM_DOORBELL "ivshmem-doorbell"
+DECLARE_INSTANCE_CHECKER(IVShmemState, IVSHMEM_DOORBELL,
+ TYPE_IVSHMEM_DOORBELL)
+
+#define TYPE_IVSHMEM "ivshmem"
+DECLARE_INSTANCE_CHECKER(IVShmemState, IVSHMEM,
+ TYPE_IVSHMEM)
+
+typedef struct Peer {
+ int nb_eventfds;
+ EventNotifier *eventfds;
+} Peer;
+
+typedef struct MSIVector {
+ PCIDevice *pdev;
+ int virq;
+ bool unmasked;
+} MSIVector;
+
+struct IVShmemState {
+ /*< private >*/
+ PCIDevice parent_obj;
+ /*< public >*/
+
+ uint32_t features;
+
+ /* exactly one of these two may be set */
+ HostMemoryBackend *hostmem; /* with interrupts */
+ CharBackend server_chr; /* without interrupts */
+
+ /* registers */
+ uint32_t intrmask;
+ uint32_t intrstatus;
+ int vm_id;
+
+ /* BARs */
+ MemoryRegion ivshmem_mmio; /* BAR 0 (registers) */
+ MemoryRegion *ivshmem_bar2; /* BAR 2 (shared memory) */
+ MemoryRegion server_bar2; /* used with server_chr */
+
+ /* interrupt support */
+ Peer *peers;
+ int nb_peers; /* space in @peers[] */
+ uint32_t vectors;
+ MSIVector *msi_vectors;
+ uint64_t msg_buf; /* buffer for receiving server messages */
+ int msg_buffered_bytes; /* #bytes in @msg_buf */
+
+ /* migration stuff */
+ OnOffAuto master;
+ Error *migration_blocker;
+};
+
+/* registers for the Inter-VM shared memory device */
+enum ivshmem_registers {
+ INTRMASK = 0,
+ INTRSTATUS = 4,
+ IVPOSITION = 8,
+ DOORBELL = 12,
+};
+
+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 void ivshmem_IntrMask_write(IVShmemState *s, uint32_t val)
+{
+ IVSHMEM_DPRINTF("IntrMask write(w) val = 0x%04x\n", val);
+
+ s->intrmask = val;
+}
+
+static uint32_t ivshmem_IntrMask_read(IVShmemState *s)
+{
+ uint32_t ret = s->intrmask;
+
+ IVSHMEM_DPRINTF("intrmask read(w) val = 0x%04x\n", ret);
+ return ret;
+}
+
+static void ivshmem_IntrStatus_write(IVShmemState *s, uint32_t val)
+{
+ IVSHMEM_DPRINTF("IntrStatus write(w) val = 0x%04x\n", val);
+
+ s->intrstatus = val;
+}
+
+static uint32_t ivshmem_IntrStatus_read(IVShmemState *s)
+{
+ uint32_t ret = s->intrstatus;
+
+ /* reading ISR clears all interrupts */
+ s->intrstatus = 0;
+ return ret;
+}
+
+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 INTRMASK:
+ ivshmem_IntrMask_write(s, val);
+ break;
+
+ case INTRSTATUS:
+ ivshmem_IntrStatus_write(s, val);
+ break;
+
+ case 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;
+ 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 INTRMASK:
+ ret = ivshmem_IntrMask_read(s);
+ break;
+
+ case INTRSTATUS:
+ ret = ivshmem_IntrStatus_read(s);
+ break;
+
+ case IVPOSITION:
+ ret = s->vm_id;
+ 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_COMMON(pdev);
+ int vector = entry - s->msi_vectors;
+ EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
+
+ if (!event_notifier_test_and_clear(n)) {
+ 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 {
+ ivshmem_IntrStatus_write(s, 1);
+ }
+}
+
+static int ivshmem_vector_unmask(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+ IVShmemState *s = IVSHMEM_COMMON(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_update_msi_route(kvm_state, v->virq, msg, dev);
+ if (ret < 0) {
+ return ret;
+ }
+ kvm_irqchip_commit_routes(kvm_state);
+
+ ret = kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, n, NULL, v->virq);
+ if (ret < 0) {
+ return ret;
+ }
+ v->unmasked = true;
+
+ return 0;
+}
+
+static void ivshmem_vector_mask(PCIDevice *dev, unsigned vector)
+{
+ IVShmemState *s = IVSHMEM_COMMON(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;
+ }
+ v->unmasked = false;
+}
+
+static void ivshmem_vector_poll(PCIDevice *dev,
+ unsigned int vector_start,
+ unsigned int vector_end)
+{
+ IVShmemState *s = IVSHMEM_COMMON(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 watch_vector_notifier(IVShmemState *s, EventNotifier *n,
+ int 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_add_eventfd(IVShmemState *s, int posn, int i)
+{
+ memory_region_add_eventfd(&s->ivshmem_mmio,
+ 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,
+ 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 = g_new0(EventNotifier, s->vectors);
+ s->peers[i].nb_eventfds = 0;
+ }
+}
+
+static void ivshmem_add_kvm_msi_virq(IVShmemState *s, int vector,
+ Error **errp)
+{
+ PCIDevice *pdev = PCI_DEVICE(s);
+ int ret;
+
+ IVSHMEM_DPRINTF("ivshmem_add_kvm_msi_virq vector:%d\n", vector);
+ assert(!s->msi_vectors[vector].pdev);
+
+ ret = kvm_irqchip_add_msi_route(kvm_state, vector, pdev);
+ if (ret < 0) {
+ error_setg(errp, "kvm_irqchip_add_msi_route failed");
+ return;
+ }
+
+ s->msi_vectors[vector].virq = ret;
+ s->msi_vectors[vector].pdev = pdev;
+}
+
+static void setup_interrupt(IVShmemState *s, int vector, Error **errp)
+{
+ EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
+ bool with_irqfd = kvm_msi_via_irqfd_enabled() &&
+ ivshmem_has_feature(s, IVSHMEM_MSI);
+ PCIDevice *pdev = PCI_DEVICE(s);
+ Error *err = NULL;
+
+ IVSHMEM_DPRINTF("setting up interrupt for vector: %d\n", vector);
+
+ if (!with_irqfd) {
+ IVSHMEM_DPRINTF("with eventfd\n");
+ watch_vector_notifier(s, n, vector);
+ } else if (msix_enabled(pdev)) {
+ IVSHMEM_DPRINTF("with irqfd\n");
+ ivshmem_add_kvm_msi_virq(s, vector, &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+
+ if (!msix_is_masked(pdev, vector)) {
+ kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, n, NULL,
+ s->msi_vectors[vector].virq);
+ /* TODO handle error */
+ }
+ } else {
+ /* it will be delayed until msix is enabled, in write_config */
+ IVSHMEM_DPRINTF("with irqfd, delayed until msix enabled\n");
+ }
+}
+
+static void process_msg_shmem(IVShmemState *s, int fd, Error **errp)
+{
+ Error *local_err = NULL;
+ struct stat buf;
+ size_t size;
+
+ if (s->ivshmem_bar2) {
+ error_setg(errp, "server sent unexpected shared memory message");
+ close(fd);
+ return;
+ }
+
+ if (fstat(fd, &buf) < 0) {
+ error_setg_errno(errp, errno,
+ "can't determine size of shared memory sent by server");
+ close(fd);
+ return;
+ }
+
+ size = buf.st_size;
+
+ /* mmap the region and map into the BAR2 */
+ memory_region_init_ram_from_fd(&s->server_bar2, OBJECT(s), "ivshmem.bar2",
+ size, RAM_SHARED, fd, 0, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ s->ivshmem_bar2 = &s->server_bar2;
+}
+
+static void process_msg_disconnect(IVShmemState *s, uint16_t posn,
+ Error **errp)
+{
+ IVSHMEM_DPRINTF("posn %d has gone away\n", posn);
+ if (posn >= s->nb_peers || posn == s->vm_id) {
+ error_setg(errp, "invalid peer %d", posn);
+ return;
+ }
+ close_peer_eventfds(s, posn);
+}
+
+static void process_msg_connect(IVShmemState *s, uint16_t posn, int fd,
+ Error **errp)
+{
+ Peer *peer = &s->peers[posn];
+ int vector;
+
+ /*
+ * The N-th connect message for this peer comes with the file
+ * descriptor for vector N-1. Count messages to find the vector.
+ */
+ if (peer->nb_eventfds >= s->vectors) {
+ error_setg(errp, "Too many eventfd received, device has %d vectors",
+ s->vectors);
+ close(fd);
+ return;
+ }
+ vector = peer->nb_eventfds++;
+
+ IVSHMEM_DPRINTF("eventfds[%d][%d] = %d\n", posn, vector, fd);
+ event_notifier_init_fd(&peer->eventfds[vector], fd);
+ fcntl_setfl(fd, O_NONBLOCK); /* msix/irqfd poll non block */
+
+ if (posn == s->vm_id) {
+ setup_interrupt(s, vector, errp);
+ /* TODO do we need to handle the error? */
+ }
+
+ if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
+ ivshmem_add_eventfd(s, posn, vector);
+ }
+}
+
+static void process_msg(IVShmemState *s, int64_t msg, int fd, Error **errp)
+{
+ IVSHMEM_DPRINTF("posn is %" PRId64 ", fd is %d\n", msg, fd);
+
+ if (msg < -1 || msg > IVSHMEM_MAX_PEERS) {
+ error_setg(errp, "server sent invalid message %" PRId64, msg);
+ close(fd);
+ return;
+ }
+
+ if (msg == -1) {
+ process_msg_shmem(s, fd, errp);
+ return;
+ }
+
+ if (msg >= s->nb_peers) {
+ resize_peers(s, msg + 1);
+ }
+
+ if (fd >= 0) {
+ process_msg_connect(s, msg, fd, errp);
+ } else {
+ process_msg_disconnect(s, msg, errp);
+ }
+}
+
+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;
+ Error *err = NULL;
+ int fd;
+ int64_t msg;
+
+ assert(size >= 0 && s->msg_buffered_bytes + size <= sizeof(s->msg_buf));
+ memcpy((unsigned char *)&s->msg_buf + s->msg_buffered_bytes, buf, size);
+ s->msg_buffered_bytes += size;
+ if (s->msg_buffered_bytes < sizeof(s->msg_buf)) {
+ return;
+ }
+ msg = le64_to_cpu(s->msg_buf);
+ s->msg_buffered_bytes = 0;
+
+ fd = qemu_chr_fe_get_msgfd(&s->server_chr);
+
+ process_msg(s, msg, fd, &err);
+ if (err) {
+ error_report_err(err);
+ }
+}
+
+static int64_t ivshmem_recv_msg(IVShmemState *s, int *pfd, Error **errp)
+{
+ int64_t msg;
+ int 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 INT64_MIN;
+ }
+ n += ret;
+ } while (n < sizeof(msg));
+
+ *pfd = qemu_chr_fe_get_msgfd(&s->server_chr);
+ return le64_to_cpu(msg);
+}
+
+static void ivshmem_recv_setup(IVShmemState *s, Error **errp)
+{
+ Error *err = NULL;
+ int64_t msg;
+ int fd;
+
+ msg = ivshmem_recv_msg(s, &fd, &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+ if (msg != IVSHMEM_PROTOCOL_VERSION) {
+ error_setg(errp, "server sent version %" PRId64 ", expecting %d",
+ msg, IVSHMEM_PROTOCOL_VERSION);
+ return;
+ }
+ if (fd != -1) {
+ error_setg(errp, "server sent invalid version message");
+ return;
+ }
+
+ /*
+ * ivshmem-server sends the remaining initial messages in a fixed
+ * order, but the device has always accepted them in any order.
+ * Stay as compatible as practical, just in case people use
+ * servers that behave differently.
+ */
+
+ /*
+ * ivshmem_device_spec.txt has always required the ID message
+ * right here, and ivshmem-server has always complied. However,
+ * older versions of the device accepted it out of order, but
+ * broke when an interrupt setup message arrived before it.
+ */
+ msg = ivshmem_recv_msg(s, &fd, &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+ if (fd != -1 || msg < 0 || msg > IVSHMEM_MAX_PEERS) {
+ error_setg(errp, "server sent invalid ID message");
+ return;
+ }
+ s->vm_id = msg;
+
+ /*
+ * Receive more messages until we got shared memory.
+ */
+ do {
+ msg = ivshmem_recv_msg(s, &fd, &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+ process_msg(s, msg, fd, &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+ } while (msg != -1);
+
+ /*
+ * This function must either map the shared memory or fail. The
+ * loop above ensures that: it terminates normally only after it
+ * successfully processed the server's shared memory message.
+ * Assert that actually mapped the shared memory:
+ */
+ assert(s->ivshmem_bar2);
+}
+
+/* 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_disable_irqfd(IVShmemState *s);
+
+static void ivshmem_reset(DeviceState *d)
+{
+ IVShmemState *s = IVSHMEM_COMMON(d);
+
+ ivshmem_disable_irqfd(s);
+
+ s->intrstatus = 0;
+ s->intrmask = 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)) {
+ return -1;
+ }
+
+ IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
+ ivshmem_msix_vector_use(s);
+ }
+
+ return 0;
+}
+
+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;
+ }
+
+ /* it was cleaned when masked in the frontend. */
+ kvm_irqchip_release_virq(kvm_state, s->msi_vectors[vector].virq);
+
+ s->msi_vectors[vector].pdev = NULL;
+}
+
+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_add_kvm_msi_virq(s, i, &err);
+ if (err) {
+ error_report_err(err);
+ goto undo;
+ }
+ }
+
+ if (msix_set_vector_notifiers(pdev,
+ ivshmem_vector_unmask,
+ ivshmem_vector_mask,
+ ivshmem_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++) {
+ /*
+ * MSI-X is already disabled here so msix_unset_vector_notifiers()
+ * didn't call our release notifier. Do it now to keep our masks and
+ * unmasks balanced.
+ */
+ if (s->msi_vectors[i].unmasked) {
+ ivshmem_vector_mask(pdev, i);
+ }
+ ivshmem_remove_kvm_msi_virq(s, i);
+ }
+
+}
+
+static void ivshmem_write_config(PCIDevice *pdev, uint32_t address,
+ uint32_t val, int len)
+{
+ IVShmemState *s = IVSHMEM_COMMON(pdev);
+ int is_enabled, was_enabled = msix_enabled(pdev);
+
+ pci_default_write_config(pdev, address, val, len);
+ is_enabled = msix_enabled(pdev);
+
+ if (kvm_msi_via_irqfd_enabled()) {
+ if (!was_enabled && is_enabled) {
+ ivshmem_enable_irqfd(s);
+ } else if (was_enabled && !is_enabled) {
+ ivshmem_disable_irqfd(s);
+ }
+ }
+}
+
+static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
+{
+ IVShmemState *s = IVSHMEM_COMMON(dev);
+ Error *err = NULL;
+ uint8_t *pci_conf;
+
+ /* 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);
+
+ if (s->hostmem != NULL) {
+ IVSHMEM_DPRINTF("using hostmem\n");
+
+ s->ivshmem_bar2 = host_memory_backend_get_memory(s->hostmem);
+ host_memory_backend_set_mapped(s->hostmem, true);
+ } else {
+ Chardev *chr = qemu_chr_fe_get_driver(&s->server_chr);
+ assert(chr);
+
+ IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
+ chr->filename);
+
+ /* we allocate enough space for 16 peers and grow as needed */
+ resize_peers(s, 16);
+
+ /*
+ * 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;
+ }
+
+ 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;
+ }
+ }
+
+ 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'");
+ if (migrate_add_blocker(s->migration_blocker, errp) < 0) {
+ error_free(s->migration_blocker);
+ return;
+ }
+ }
+
+ vmstate_register_ram(s->ivshmem_bar2, DEVICE(s));
+ 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_exit(PCIDevice *dev)
+{
+ IVShmemState *s = IVSHMEM_COMMON(dev);
+ int i;
+
+ if (s->migration_blocker) {
+ migrate_del_blocker(s->migration_blocker);
+ error_free(s->migration_blocker);
+ }
+
+ if (memory_region_is_mapped(s->ivshmem_bar2)) {
+ if (!s->hostmem) {
+ void *addr = memory_region_get_ram_ptr(s->ivshmem_bar2);
+ int fd;
+
+ if (munmap(addr, memory_region_size(s->ivshmem_bar2) == -1)) {
+ error_report("Failed to munmap shared memory %s",
+ strerror(errno));
+ }
+
+ fd = memory_region_get_fd(s->ivshmem_bar2);
+ close(fd);
+ }
+
+ vmstate_unregister_ram(s->ivshmem_bar2, DEVICE(dev));
+ }
+
+ if (s->hostmem) {
+ host_memory_backend_set_mapped(s->hostmem, false);
+ }
+
+ 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 void ivshmem_common_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+
+ k->realize = ivshmem_common_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;
+ k->class_id = PCI_CLASS_MEMORY_RAM;
+ k->revision = 1;
+ dc->reset = ivshmem_reset;
+ set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+ dc->desc = "Inter-VM shared memory";
+}
+
+static const TypeInfo ivshmem_common_info = {
+ .name = TYPE_IVSHMEM_COMMON,
+ .parent = TYPE_PCI_DEVICE,
+ .instance_size = sizeof(IVShmemState),
+ .abstract = true,
+ .class_init = ivshmem_common_class_init,
+ .interfaces = (InterfaceInfo[]) {
+ { INTERFACE_CONVENTIONAL_PCI_DEVICE },
+ { },
+ },
+};
+
+static const VMStateDescription ivshmem_plain_vmsd = {
+ .name = TYPE_IVSHMEM_PLAIN,
+ .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_UINT32(intrstatus, IVShmemState),
+ VMSTATE_UINT32(intrmask, IVShmemState),
+ VMSTATE_END_OF_LIST()
+ },
+};
+
+static Property ivshmem_plain_properties[] = {
+ DEFINE_PROP_ON_OFF_AUTO("master", IVShmemState, master, ON_OFF_AUTO_OFF),
+ DEFINE_PROP_LINK("memdev", IVShmemState, hostmem, TYPE_MEMORY_BACKEND,
+ HostMemoryBackend *),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void ivshmem_plain_realize(PCIDevice *dev, Error **errp)
+{
+ IVShmemState *s = IVSHMEM_COMMON(dev);
+
+ if (!s->hostmem) {
+ error_setg(errp, "You must specify a 'memdev'");
+ return;
+ } else if (host_memory_backend_is_mapped(s->hostmem)) {
+ error_setg(errp, "can't use already busy memdev: %s",
+ object_get_canonical_path_component(OBJECT(s->hostmem)));
+ return;
+ }
+
+ ivshmem_common_realize(dev, errp);
+}
+
+static void ivshmem_plain_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+
+ k->realize = ivshmem_plain_realize;
+ device_class_set_props(dc, ivshmem_plain_properties);
+ dc->vmsd = &ivshmem_plain_vmsd;
+}
+
+static const TypeInfo ivshmem_plain_info = {
+ .name = TYPE_IVSHMEM_PLAIN,
+ .parent = TYPE_IVSHMEM_COMMON,
+ .instance_size = sizeof(IVShmemState),
+ .class_init = ivshmem_plain_class_init,
+};
+
+static const VMStateDescription ivshmem_doorbell_vmsd = {
+ .name = TYPE_IVSHMEM_DOORBELL,
+ .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(intrstatus, IVShmemState),
+ VMSTATE_UINT32(intrmask, IVShmemState),
+ VMSTATE_END_OF_LIST()
+ },
+};
+
+static Property ivshmem_doorbell_properties[] = {
+ DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
+ DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
+ 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_doorbell_init(Object *obj)
+{
+ IVShmemState *s = IVSHMEM_DOORBELL(obj);
+
+ s->features |= (1 << IVSHMEM_MSI);
+}
+
+static void ivshmem_doorbell_realize(PCIDevice *dev, Error **errp)
+{
+ IVShmemState *s = IVSHMEM_COMMON(dev);
+
+ if (!qemu_chr_fe_backend_connected(&s->server_chr)) {
+ error_setg(errp, "You must specify a 'chardev'");
+ return;
+ }
+
+ ivshmem_common_realize(dev, errp);
+}
+
+static void ivshmem_doorbell_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+
+ k->realize = ivshmem_doorbell_realize;
+ device_class_set_props(dc, ivshmem_doorbell_properties);
+ dc->vmsd = &ivshmem_doorbell_vmsd;
+}
+
+static const TypeInfo ivshmem_doorbell_info = {
+ .name = TYPE_IVSHMEM_DOORBELL,
+ .parent = TYPE_IVSHMEM_COMMON,
+ .instance_size = sizeof(IVShmemState),
+ .instance_init = ivshmem_doorbell_init,
+ .class_init = ivshmem_doorbell_class_init,
+};
+
+static void ivshmem_register_types(void)
+{
+ type_register_static(&ivshmem_common_info);
+ type_register_static(&ivshmem_plain_info);
+ type_register_static(&ivshmem_doorbell_info);
+}
+
+type_init(ivshmem_register_types)