qemu/hw/misc/ivshmem.c
Daniel Henrique Barboza ef80a708b5 ivshmem.c: change endianness to LITTLE_ENDIAN
The ivshmem device, as with most PCI devices, uses little endian byte
order. However, the endianness of its mmio_ops is marked as
DEVICE_NATIVE_ENDIAN. This presents not only the usual problems with big
endian hosts but also with PowerPC little endian hosts as well, since
the Power architecture in QEMU uses big endian hardware (XIVE controller,
PCI Host Bridges, etc) even if the host is in little endian byte order.

As it is today, the IVPosition of the device will be byte swapped when
running in Power BE and LE. This can be seen by changing the existing
qtest 'ivshmem-test' to run in ppc64 hosts and printing the IVPOSITION
regs in test_ivshmem_server() right after the VM ids assert. For x86_64
the VM id values read are '0' and '1', for ppc64 (tested in a Power8
RHEL 7.9 BE server) and ppc64le (tested in a Power9 RHEL 8.6 LE server)
the ids will be '0' and '0x1000000'.

Change this device to LITTLE_ENDIAN fixes the issue for Power hosts of
both endianness, and every other big-endian architecture that might use
this device, without impacting x86 users.

Fixes: cb06608e17 ("ivshmem: convert to memory API")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/168
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211124092948.335389-2-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2021-12-17 17:57:13 +01:00

1136 lines
31 KiB
C

/*
* 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_LITTLE_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)