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-rw-r--r--src/hw/misc/ivshmem.c1200
1 files changed, 1200 insertions, 0 deletions
diff --git a/src/hw/misc/ivshmem.c b/src/hw/misc/ivshmem.c
new file mode 100644
index 0000000..dcfc8cc
--- /dev/null
+++ b/src/hw/misc/ivshmem.c
@@ -0,0 +1,1200 @@
+/*
+ * 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 "hw/hw.h"
+#include "hw/i386/pc.h"
+#include "hw/pci/pci.h"
+#include "hw/pci/msi.h"
+#include "hw/pci/msix.h"
+#include "sysemu/kvm.h"
+#include "migration/migration.h"
+#include "qemu/error-report.h"
+#include "qemu/event_notifier.h"
+#include "qemu/fifo8.h"
+#include "sysemu/char.h"
+#include "sysemu/hostmem.h"
+#include "qapi/visitor.h"
+
+#include "hw/misc/ivshmem.h"
+
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <limits.h>
+
+#define PCI_VENDOR_ID_IVSHMEM PCI_VENDOR_ID_REDHAT_QUMRANET
+#define PCI_DEVICE_ID_IVSHMEM 0x1110
+
+#define IVSHMEM_MAX_PEERS G_MAXUINT16
+#define IVSHMEM_IOEVENTFD 0
+#define IVSHMEM_MSI 1
+
+#define IVSHMEM_PEER 0
+#define IVSHMEM_MASTER 1
+
+#define IVSHMEM_REG_BAR_SIZE 0x100
+
+//#define DEBUG_IVSHMEM
+#ifdef DEBUG_IVSHMEM
+#define IVSHMEM_DPRINTF(fmt, ...) \
+ do {printf("IVSHMEM: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define IVSHMEM_DPRINTF(fmt, ...)
+#endif
+
+#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;
+} MSIVector;
+
+typedef struct IVShmemState {
+ /*< private >*/
+ PCIDevice parent_obj;
+ /*< public >*/
+
+ HostMemoryBackend *hostmem;
+ uint32_t intrmask;
+ uint32_t intrstatus;
+
+ CharDriverState **eventfd_chr;
+ CharDriverState *server_chr;
+ Fifo8 incoming_fifo;
+ MemoryRegion ivshmem_mmio;
+
+ /* We might need to register the BAR before we actually have the memory.
+ * So prepare a container MemoryRegion for the BAR immediately and
+ * add a subregion when we have the memory.
+ */
+ MemoryRegion bar;
+ MemoryRegion ivshmem;
+ uint64_t ivshmem_size; /* size of shared memory region */
+ uint32_t ivshmem_64bit;
+
+ Peer *peers;
+ int nb_peers; /* how many peers we have space for */
+
+ int vm_id;
+ uint32_t vectors;
+ uint32_t features;
+ MSIVector *msi_vectors;
+
+ Error *migration_blocker;
+
+ char * shmobj;
+ char * sizearg;
+ char * role;
+ int role_val; /* scalar to avoid multiple string comparisons */
+} IVShmemState;
+
+/* 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));
+}
+
+/* accessing registers - based on rtl8139 */
+static void ivshmem_update_irq(IVShmemState *s)
+{
+ PCIDevice *d = PCI_DEVICE(s);
+ int isr;
+ isr = (s->intrstatus & s->intrmask) & 0xffffffff;
+
+ /* don't print ISR resets */
+ if (isr) {
+ IVSHMEM_DPRINTF("Set IRQ to %d (%04x %04x)\n",
+ isr ? 1 : 0, s->intrstatus, s->intrmask);
+ }
+
+ pci_set_irq(d, (isr != 0));
+}
+
+static void ivshmem_IntrMask_write(IVShmemState *s, uint32_t val)
+{
+ IVSHMEM_DPRINTF("IntrMask write(w) val = 0x%04x\n", val);
+
+ s->intrmask = val;
+
+ ivshmem_update_irq(s);
+}
+
+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;
+
+ ivshmem_update_irq(s);
+}
+
+static uint32_t ivshmem_IntrStatus_read(IVShmemState *s)
+{
+ uint32_t ret = s->intrstatus;
+
+ /* reading ISR clears all interrupts */
+ s->intrstatus = 0;
+
+ ivshmem_update_irq(s);
+
+ 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:
+ /* return my VM ID if the memory is mapped */
+ if (memory_region_is_mapped(&s->ivshmem)) {
+ ret = s->vm_id;
+ } else {
+ ret = -1;
+ }
+ 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_receive(void *opaque, const uint8_t *buf, int size)
+{
+ IVShmemState *s = opaque;
+
+ IVSHMEM_DPRINTF("ivshmem_receive 0x%02x size: %d\n", *buf, size);
+
+ ivshmem_IntrStatus_write(s, *buf);
+}
+
+static int ivshmem_can_receive(void * opaque)
+{
+ return sizeof(int64_t);
+}
+
+static void ivshmem_event(void *opaque, int event)
+{
+ IVSHMEM_DPRINTF("ivshmem_event %d\n", event);
+}
+
+static void fake_irqfd(void *opaque, const uint8_t *buf, int size) {
+
+ MSIVector *entry = opaque;
+ PCIDevice *pdev = entry->pdev;
+ IVShmemState *s = IVSHMEM(pdev);
+ int vector = entry - s->msi_vectors;
+
+ IVSHMEM_DPRINTF("interrupt on vector %p %d\n", pdev, vector);
+ msix_notify(pdev, vector);
+}
+
+static int ivshmem_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);
+
+ ret = kvm_irqchip_update_msi_route(kvm_state, v->virq, msg, dev);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, n, NULL, v->virq);
+}
+
+static void ivshmem_vector_mask(PCIDevice *dev, unsigned vector)
+{
+ IVShmemState *s = IVSHMEM(dev);
+ EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
+ int ret;
+
+ IVSHMEM_DPRINTF("vector mask %p %d\n", dev, vector);
+
+ ret = kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, n,
+ s->msi_vectors[vector].virq);
+ if (ret != 0) {
+ error_report("remove_irqfd_notifier_gsi failed");
+ }
+}
+
+static void ivshmem_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 CharDriverState* create_eventfd_chr_device(IVShmemState *s,
+ EventNotifier *n,
+ int vector)
+{
+ /* create a event character device based on the passed eventfd */
+ int eventfd = event_notifier_get_fd(n);
+ CharDriverState *chr;
+
+ chr = qemu_chr_open_eventfd(eventfd);
+
+ if (chr == NULL) {
+ error_report("creating chardriver for eventfd %d failed", eventfd);
+ return NULL;
+ }
+ qemu_chr_fe_claim_no_fail(chr);
+
+ /* if MSI is supported we need multiple interrupts */
+ if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
+ s->msi_vectors[vector].pdev = PCI_DEVICE(s);
+
+ qemu_chr_add_handlers(chr, ivshmem_can_receive, fake_irqfd,
+ ivshmem_event, &s->msi_vectors[vector]);
+ } else {
+ qemu_chr_add_handlers(chr, ivshmem_can_receive, ivshmem_receive,
+ ivshmem_event, s);
+ }
+
+ return chr;
+
+}
+
+static int check_shm_size(IVShmemState *s, int fd, Error **errp)
+{
+ /* check that the guest isn't going to try and map more memory than the
+ * the object has allocated return -1 to indicate error */
+
+ struct stat buf;
+
+ if (fstat(fd, &buf) < 0) {
+ error_setg(errp, "exiting: fstat on fd %d failed: %s",
+ fd, strerror(errno));
+ return -1;
+ }
+
+ if (s->ivshmem_size > buf.st_size) {
+ error_setg(errp, "Requested memory size greater"
+ " than shared object size (%" PRIu64 " > %" PRIu64")",
+ s->ivshmem_size, (uint64_t)buf.st_size);
+ return -1;
+ } else {
+ return 0;
+ }
+}
+
+/* create the shared memory BAR when we are not using the server, so we can
+ * create the BAR and map the memory immediately */
+static int create_shared_memory_BAR(IVShmemState *s, int fd, uint8_t attr,
+ Error **errp)
+{
+ void * ptr;
+
+ ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+ if (ptr == MAP_FAILED) {
+ error_setg_errno(errp, errno, "Failed to mmap shared memory");
+ return -1;
+ }
+
+ memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s), "ivshmem.bar2",
+ s->ivshmem_size, ptr);
+ vmstate_register_ram(&s->ivshmem, DEVICE(s));
+ memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
+
+ /* region for shared memory */
+ pci_register_bar(PCI_DEVICE(s), 2, attr, &s->bar);
+
+ return 0;
+}
+
+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;
+
+ if (!ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
+ return;
+ }
+ if (posn < 0 || posn >= s->nb_peers) {
+ error_report("invalid peer %d", posn);
+ return;
+ }
+
+ n = s->peers[posn].nb_eventfds;
+
+ 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;
+}
+
+/* this function increase the dynamic storage need to store data about other
+ * peers */
+static int resize_peers(IVShmemState *s, int new_min_size)
+{
+
+ int j, old_size;
+
+ /* limit number of max peers */
+ if (new_min_size <= 0 || new_min_size > IVSHMEM_MAX_PEERS) {
+ return -1;
+ }
+ if (new_min_size <= s->nb_peers) {
+ return 0;
+ }
+
+ old_size = s->nb_peers;
+ s->nb_peers = new_min_size;
+
+ IVSHMEM_DPRINTF("bumping storage to %d peers\n", s->nb_peers);
+
+ s->peers = g_realloc(s->peers, s->nb_peers * sizeof(Peer));
+
+ for (j = old_size; j < s->nb_peers; j++) {
+ s->peers[j].eventfds = g_new0(EventNotifier, s->vectors);
+ s->peers[j].nb_eventfds = 0;
+ }
+
+ return 0;
+}
+
+static bool fifo_update_and_get(IVShmemState *s, const uint8_t *buf, int size,
+ void *data, size_t len)
+{
+ const uint8_t *p;
+ uint32_t num;
+
+ assert(len <= sizeof(int64_t)); /* limitation of the fifo */
+ if (fifo8_is_empty(&s->incoming_fifo) && size == len) {
+ memcpy(data, buf, size);
+ return true;
+ }
+
+ IVSHMEM_DPRINTF("short read of %d bytes\n", size);
+
+ num = MIN(size, sizeof(int64_t) - fifo8_num_used(&s->incoming_fifo));
+ fifo8_push_all(&s->incoming_fifo, buf, num);
+
+ if (fifo8_num_used(&s->incoming_fifo) < len) {
+ assert(num == 0);
+ return false;
+ }
+
+ size -= num;
+ buf += num;
+ p = fifo8_pop_buf(&s->incoming_fifo, len, &num);
+ assert(num == len);
+
+ memcpy(data, p, len);
+
+ if (size > 0) {
+ fifo8_push_all(&s->incoming_fifo, buf, size);
+ }
+
+ return true;
+}
+
+static bool fifo_update_and_get_i64(IVShmemState *s,
+ const uint8_t *buf, int size, int64_t *i64)
+{
+ if (fifo_update_and_get(s, buf, size, i64, sizeof(*i64))) {
+ *i64 = GINT64_FROM_LE(*i64);
+ return true;
+ }
+
+ return false;
+}
+
+static int ivshmem_add_kvm_msi_virq(IVShmemState *s, int vector)
+{
+ PCIDevice *pdev = PCI_DEVICE(s);
+ MSIMessage msg = msix_get_message(pdev, vector);
+ int ret;
+
+ IVSHMEM_DPRINTF("ivshmem_add_kvm_msi_virq vector:%d\n", vector);
+
+ if (s->msi_vectors[vector].pdev != NULL) {
+ return 0;
+ }
+
+ ret = kvm_irqchip_add_msi_route(kvm_state, msg, pdev);
+ if (ret < 0) {
+ error_report("ivshmem: kvm_irqchip_add_msi_route failed");
+ return -1;
+ }
+
+ s->msi_vectors[vector].virq = ret;
+ s->msi_vectors[vector].pdev = pdev;
+
+ return 0;
+}
+
+static void setup_interrupt(IVShmemState *s, int vector)
+{
+ 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);
+
+ IVSHMEM_DPRINTF("setting up interrupt for vector: %d\n", vector);
+
+ if (!with_irqfd) {
+ IVSHMEM_DPRINTF("with eventfd");
+ s->eventfd_chr[vector] = create_eventfd_chr_device(s, n, vector);
+ } else if (msix_enabled(pdev)) {
+ IVSHMEM_DPRINTF("with irqfd");
+ if (ivshmem_add_kvm_msi_virq(s, vector) < 0) {
+ return;
+ }
+
+ if (!msix_is_masked(pdev, vector)) {
+ kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, n, NULL,
+ s->msi_vectors[vector].virq);
+ }
+ } else {
+ /* it will be delayed until msix is enabled, in write_config */
+ IVSHMEM_DPRINTF("with irqfd, delayed until msix enabled");
+ }
+}
+
+static void ivshmem_read(void *opaque, const uint8_t *buf, int size)
+{
+ IVShmemState *s = opaque;
+ int incoming_fd;
+ int new_eventfd;
+ int64_t incoming_posn;
+ Error *err = NULL;
+ Peer *peer;
+
+ if (!fifo_update_and_get_i64(s, buf, size, &incoming_posn)) {
+ return;
+ }
+
+ if (incoming_posn < -1) {
+ IVSHMEM_DPRINTF("invalid incoming_posn %" PRId64 "\n", incoming_posn);
+ return;
+ }
+
+ /* pick off s->server_chr->msgfd and store it, posn should accompany msg */
+ incoming_fd = qemu_chr_fe_get_msgfd(s->server_chr);
+ IVSHMEM_DPRINTF("posn is %" PRId64 ", fd is %d\n",
+ incoming_posn, incoming_fd);
+
+ /* make sure we have enough space for this peer */
+ if (incoming_posn >= s->nb_peers) {
+ if (resize_peers(s, incoming_posn + 1) < 0) {
+ error_report("failed to resize peers array");
+ if (incoming_fd != -1) {
+ close(incoming_fd);
+ }
+ return;
+ }
+ }
+
+ peer = &s->peers[incoming_posn];
+
+ if (incoming_fd == -1) {
+ /* if posn is positive and unseen before then this is our posn*/
+ if (incoming_posn >= 0 && s->vm_id == -1) {
+ /* receive our posn */
+ s->vm_id = incoming_posn;
+ } else {
+ /* otherwise an fd == -1 means an existing peer has gone away */
+ IVSHMEM_DPRINTF("posn %" PRId64 " has gone away\n", incoming_posn);
+ close_peer_eventfds(s, incoming_posn);
+ }
+ return;
+ }
+
+ /* if the position is -1, then it's shared memory region fd */
+ if (incoming_posn == -1) {
+ void * map_ptr;
+
+ if (memory_region_is_mapped(&s->ivshmem)) {
+ error_report("shm already initialized");
+ close(incoming_fd);
+ return;
+ }
+
+ if (check_shm_size(s, incoming_fd, &err) == -1) {
+ error_report_err(err);
+ close(incoming_fd);
+ return;
+ }
+
+ /* mmap the region and map into the BAR2 */
+ map_ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED,
+ incoming_fd, 0);
+ if (map_ptr == MAP_FAILED) {
+ error_report("Failed to mmap shared memory %s", strerror(errno));
+ close(incoming_fd);
+ return;
+ }
+ memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s),
+ "ivshmem.bar2", s->ivshmem_size, map_ptr);
+ vmstate_register_ram(&s->ivshmem, DEVICE(s));
+
+ IVSHMEM_DPRINTF("guest h/w addr = %p, size = %" PRIu64 "\n",
+ map_ptr, s->ivshmem_size);
+
+ memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
+
+ close(incoming_fd);
+ return;
+ }
+
+ /* each peer has an associated array of eventfds, and we keep
+ * track of how many eventfds received so far */
+ /* get a new eventfd: */
+ if (peer->nb_eventfds >= s->vectors) {
+ error_report("Too many eventfd received, device has %d vectors",
+ s->vectors);
+ close(incoming_fd);
+ return;
+ }
+
+ new_eventfd = peer->nb_eventfds++;
+
+ /* this is an eventfd for a particular peer VM */
+ IVSHMEM_DPRINTF("eventfds[%" PRId64 "][%d] = %d\n", incoming_posn,
+ new_eventfd, incoming_fd);
+ event_notifier_init_fd(&peer->eventfds[new_eventfd], incoming_fd);
+ fcntl_setfl(incoming_fd, O_NONBLOCK); /* msix/irqfd poll non block */
+
+ if (incoming_posn == s->vm_id) {
+ setup_interrupt(s, new_eventfd);
+ }
+
+ if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
+ ivshmem_add_eventfd(s, incoming_posn, new_eventfd);
+ }
+}
+
+static void ivshmem_check_version(void *opaque, const uint8_t * buf, int size)
+{
+ IVShmemState *s = opaque;
+ int tmp;
+ int64_t version;
+
+ if (!fifo_update_and_get_i64(s, buf, size, &version)) {
+ return;
+ }
+
+ tmp = qemu_chr_fe_get_msgfd(s->server_chr);
+ if (tmp != -1 || version != IVSHMEM_PROTOCOL_VERSION) {
+ fprintf(stderr, "incompatible version, you are connecting to a ivshmem-"
+ "server using a different protocol please check your setup\n");
+ qemu_chr_delete(s->server_chr);
+ s->server_chr = NULL;
+ return;
+ }
+
+ IVSHMEM_DPRINTF("version check ok, switch to real chardev handler\n");
+ qemu_chr_add_handlers(s->server_chr, ivshmem_can_receive, ivshmem_read,
+ ivshmem_event, s);
+}
+
+/* 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_use_msix(IVShmemState * s)
+{
+ PCIDevice *d = PCI_DEVICE(s);
+ int i;
+
+ IVSHMEM_DPRINTF("%s, msix present: %d\n", __func__, msix_present(d));
+ if (!msix_present(d)) {
+ return;
+ }
+
+ for (i = 0; i < s->vectors; i++) {
+ msix_vector_use(d, i);
+ }
+}
+
+static void ivshmem_reset(DeviceState *d)
+{
+ IVShmemState *s = IVSHMEM(d);
+
+ s->intrstatus = 0;
+ s->intrmask = 0;
+ ivshmem_use_msix(s);
+}
+
+static int ivshmem_setup_msi(IVShmemState * s)
+{
+ if (msix_init_exclusive_bar(PCI_DEVICE(s), s->vectors, 1)) {
+ return -1;
+ }
+
+ IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
+
+ /* allocate QEMU char devices for receiving interrupts */
+ s->msi_vectors = g_malloc0(s->vectors * sizeof(MSIVector));
+
+ ivshmem_use_msix(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++) {
+ ivshmem_add_kvm_msi_virq(s, i);
+ }
+
+ if (msix_set_vector_notifiers(pdev,
+ ivshmem_vector_unmask,
+ ivshmem_vector_mask,
+ ivshmem_vector_poll)) {
+ error_report("ivshmem: msix_set_vector_notifiers failed");
+ }
+}
+
+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_disable_irqfd(IVShmemState *s)
+{
+ PCIDevice *pdev = PCI_DEVICE(s);
+ int i;
+
+ for (i = 0; i < s->peers[s->vm_id].nb_eventfds; i++) {
+ ivshmem_remove_kvm_msi_virq(s, i);
+ }
+
+ msix_unset_vector_notifiers(pdev);
+}
+
+static void ivshmem_write_config(PCIDevice *pdev, uint32_t address,
+ uint32_t val, int len)
+{
+ IVShmemState *s = IVSHMEM(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() && s->vm_id != -1) {
+ if (!was_enabled && is_enabled) {
+ ivshmem_enable_irqfd(s);
+ } else if (was_enabled && !is_enabled) {
+ ivshmem_disable_irqfd(s);
+ }
+ }
+}
+
+static void pci_ivshmem_realize(PCIDevice *dev, Error **errp)
+{
+ IVShmemState *s = IVSHMEM(dev);
+ uint8_t *pci_conf;
+ uint8_t attr = PCI_BASE_ADDRESS_SPACE_MEMORY |
+ PCI_BASE_ADDRESS_MEM_PREFETCH;
+
+ if (!!s->server_chr + !!s->shmobj + !!s->hostmem != 1) {
+ error_setg(errp,
+ "You must specify either 'shm', 'chardev' or 'x-memdev'");
+ return;
+ }
+
+ if (s->hostmem) {
+ MemoryRegion *mr;
+
+ if (s->sizearg) {
+ g_warning("size argument ignored with hostmem");
+ }
+
+ mr = host_memory_backend_get_memory(s->hostmem, errp);
+ s->ivshmem_size = memory_region_size(mr);
+ } else if (s->sizearg == NULL) {
+ s->ivshmem_size = 4 << 20; /* 4 MB default */
+ } else {
+ char *end;
+ int64_t size = qemu_strtosz(s->sizearg, &end);
+ if (size < 0 || *end != '\0' || !is_power_of_2(size)) {
+ error_setg(errp, "Invalid size %s", s->sizearg);
+ return;
+ }
+ s->ivshmem_size = size;
+ }
+
+ fifo8_create(&s->incoming_fifo, sizeof(int64_t));
+
+ /* IRQFD requires MSI */
+ if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
+ !ivshmem_has_feature(s, IVSHMEM_MSI)) {
+ error_setg(errp, "ioeventfd/irqfd requires MSI");
+ return;
+ }
+
+ /* check that role is reasonable */
+ if (s->role) {
+ if (strncmp(s->role, "peer", 5) == 0) {
+ s->role_val = IVSHMEM_PEER;
+ } else if (strncmp(s->role, "master", 7) == 0) {
+ s->role_val = IVSHMEM_MASTER;
+ } else {
+ error_setg(errp, "'role' must be 'peer' or 'master'");
+ return;
+ }
+ } else {
+ s->role_val = IVSHMEM_MASTER; /* default */
+ }
+
+ if (s->role_val == IVSHMEM_PEER) {
+ error_setg(&s->migration_blocker,
+ "Migration is disabled when using feature 'peer mode' in device 'ivshmem'");
+ migrate_add_blocker(s->migration_blocker);
+ }
+
+ pci_conf = dev->config;
+ pci_conf[PCI_COMMAND] = PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
+
+ pci_config_set_interrupt_pin(pci_conf, 1);
+
+ 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);
+
+ memory_region_init(&s->bar, OBJECT(s), "ivshmem-bar2-container", s->ivshmem_size);
+ if (s->ivshmem_64bit) {
+ attr |= PCI_BASE_ADDRESS_MEM_TYPE_64;
+ }
+
+ if (s->hostmem != NULL) {
+ MemoryRegion *mr;
+
+ IVSHMEM_DPRINTF("using hostmem\n");
+
+ mr = host_memory_backend_get_memory(MEMORY_BACKEND(s->hostmem), errp);
+ vmstate_register_ram(mr, DEVICE(s));
+ memory_region_add_subregion(&s->bar, 0, mr);
+ pci_register_bar(PCI_DEVICE(s), 2, attr, &s->bar);
+ } else if (s->server_chr != NULL) {
+ /* FIXME do not rely on what chr drivers put into filename */
+ if (strncmp(s->server_chr->filename, "unix:", 5)) {
+ error_setg(errp, "chardev is not a unix client socket");
+ return;
+ }
+
+ /* if we get a UNIX socket as the parameter we will talk
+ * to the ivshmem server to receive the memory region */
+
+ IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
+ s->server_chr->filename);
+
+ if (ivshmem_has_feature(s, IVSHMEM_MSI) &&
+ ivshmem_setup_msi(s)) {
+ error_setg(errp, "msix initialization failed");
+ return;
+ }
+
+ /* we allocate enough space for 16 peers and grow as needed */
+ resize_peers(s, 16);
+ s->vm_id = -1;
+
+ pci_register_bar(dev, 2, attr, &s->bar);
+
+ s->eventfd_chr = g_malloc0(s->vectors * sizeof(CharDriverState *));
+
+ qemu_chr_add_handlers(s->server_chr, ivshmem_can_receive,
+ ivshmem_check_version, ivshmem_event, s);
+ } else {
+ /* just map the file immediately, we're not using a server */
+ int fd;
+
+ IVSHMEM_DPRINTF("using shm_open (shm object = %s)\n", s->shmobj);
+
+ /* try opening with O_EXCL and if it succeeds zero the memory
+ * by truncating to 0 */
+ if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR|O_EXCL,
+ S_IRWXU|S_IRWXG|S_IRWXO)) > 0) {
+ /* truncate file to length PCI device's memory */
+ if (ftruncate(fd, s->ivshmem_size) != 0) {
+ error_report("could not truncate shared file");
+ }
+
+ } else if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR,
+ S_IRWXU|S_IRWXG|S_IRWXO)) < 0) {
+ error_setg(errp, "could not open shared file");
+ return;
+ }
+
+ if (check_shm_size(s, fd, errp) == -1) {
+ return;
+ }
+
+ create_shared_memory_BAR(s, fd, attr, errp);
+ close(fd);
+ }
+}
+
+static void pci_ivshmem_exit(PCIDevice *dev)
+{
+ IVShmemState *s = IVSHMEM(dev);
+ int i;
+
+ fifo8_destroy(&s->incoming_fifo);
+
+ if (s->migration_blocker) {
+ migrate_del_blocker(s->migration_blocker);
+ error_free(s->migration_blocker);
+ }
+
+ if (memory_region_is_mapped(&s->ivshmem)) {
+ if (!s->hostmem) {
+ void *addr = memory_region_get_ram_ptr(&s->ivshmem);
+
+ if (munmap(addr, s->ivshmem_size) == -1) {
+ error_report("Failed to munmap shared memory %s",
+ strerror(errno));
+ }
+ }
+
+ vmstate_unregister_ram(&s->ivshmem, DEVICE(dev));
+ memory_region_del_subregion(&s->bar, &s->ivshmem);
+ }
+
+ if (s->eventfd_chr) {
+ for (i = 0; i < s->vectors; i++) {
+ if (s->eventfd_chr[i]) {
+ qemu_chr_free(s->eventfd_chr[i]);
+ }
+ }
+ g_free(s->eventfd_chr);
+ }
+
+ 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 bool test_msix(void *opaque, int version_id)
+{
+ IVShmemState *s = opaque;
+
+ return ivshmem_has_feature(s, IVSHMEM_MSI);
+}
+
+static bool test_no_msix(void *opaque, int version_id)
+{
+ return !test_msix(opaque, version_id);
+}
+
+static int ivshmem_pre_load(void *opaque)
+{
+ IVShmemState *s = opaque;
+
+ if (s->role_val == IVSHMEM_PEER) {
+ 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_use_msix(s);
+ }
+
+ return 0;
+}
+
+static int ivshmem_load_old(QEMUFile *f, void *opaque, int version_id)
+{
+ IVShmemState *s = opaque;
+ PCIDevice *pdev = PCI_DEVICE(s);
+ int ret;
+
+ IVSHMEM_DPRINTF("ivshmem_load_old\n");
+
+ if (version_id != 0) {
+ return -EINVAL;
+ }
+
+ if (s->role_val == IVSHMEM_PEER) {
+ error_report("'peer' devices are not migratable");
+ return -EINVAL;
+ }
+
+ ret = pci_device_load(pdev, f);
+ if (ret) {
+ return ret;
+ }
+
+ if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
+ msix_load(pdev, f);
+ ivshmem_use_msix(s);
+ } else {
+ s->intrstatus = qemu_get_be32(f);
+ s->intrmask = qemu_get_be32(f);
+ }
+
+ return 0;
+}
+
+static const VMStateDescription ivshmem_vmsd = {
+ .name = "ivshmem",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .pre_load = ivshmem_pre_load,
+ .post_load = ivshmem_post_load,
+ .fields = (VMStateField[]) {
+ VMSTATE_PCI_DEVICE(parent_obj, IVShmemState),
+
+ VMSTATE_MSIX_TEST(parent_obj, IVShmemState, test_msix),
+ VMSTATE_UINT32_TEST(intrstatus, IVShmemState, test_no_msix),
+ VMSTATE_UINT32_TEST(intrmask, IVShmemState, test_no_msix),
+
+ VMSTATE_END_OF_LIST()
+ },
+ .load_state_old = ivshmem_load_old,
+ .minimum_version_id_old = 0
+};
+
+static Property ivshmem_properties[] = {
+ DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
+ DEFINE_PROP_STRING("size", IVShmemState, sizearg),
+ DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
+ DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD, false),
+ DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
+ DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
+ DEFINE_PROP_STRING("role", IVShmemState, role),
+ DEFINE_PROP_UINT32("use64", IVShmemState, ivshmem_64bit, 1),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void ivshmem_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+
+ k->realize = pci_ivshmem_realize;
+ k->exit = pci_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;
+ dc->reset = ivshmem_reset;
+ dc->props = ivshmem_properties;
+ dc->vmsd = &ivshmem_vmsd;
+ set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+ dc->desc = "Inter-VM shared memory";
+}
+
+static void ivshmem_check_memdev_is_busy(Object *obj, const char *name,
+ Object *val, Error **errp)
+{
+ MemoryRegion *mr;
+
+ mr = host_memory_backend_get_memory(MEMORY_BACKEND(val), errp);
+ if (memory_region_is_mapped(mr)) {
+ char *path = object_get_canonical_path_component(val);
+ error_setg(errp, "can't use already busy memdev: %s", path);
+ g_free(path);
+ } else {
+ qdev_prop_allow_set_link_before_realize(obj, name, val, errp);
+ }
+}
+
+static void ivshmem_init(Object *obj)
+{
+ IVShmemState *s = IVSHMEM(obj);
+
+ object_property_add_link(obj, "x-memdev", TYPE_MEMORY_BACKEND,
+ (Object **)&s->hostmem,
+ ivshmem_check_memdev_is_busy,
+ OBJ_PROP_LINK_UNREF_ON_RELEASE,
+ &error_abort);
+}
+
+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,
+};
+
+static void ivshmem_register_types(void)
+{
+ type_register_static(&ivshmem_info);
+}
+
+type_init(ivshmem_register_types)
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