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qemu/hw/vfio/common.c
Avihai Horon 31bcbbb5be vfio/migration: Implement VFIO migration protocol v2 
Implement the basic mandatory part of VFIO migration protocol v2.
This includes all functionality that is necessary to support
VFIO_MIGRATION_STOP_COPY part of the v2 protocol.

The two protocols, v1 and v2, will co-exist and in the following patches
v1 protocol code will be removed.

There are several main differences between v1 and v2 protocols:
- VFIO device state is now represented as a finite state machine instead
  of a bitmap.

- Migration interface with kernel is now done using VFIO_DEVICE_FEATURE
  ioctl and normal read() and write() instead of the migration region.

- Pre-copy is made optional in v2 protocol. Support for pre-copy will be
  added later on.

Detailed information about VFIO migration protocol v2 and its difference
compared to v1 protocol can be found here [1].

[1]
https://lore.kernel.org/all/20220224142024.147653-10-yishaih@nvidia.com/

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>.
Link: https://lore.kernel.org/r/20230216143630.25610-9-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-02-16 12:13:46 -07:00

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/*
* generic functions used by VFIO devices
*
* Copyright Red Hat, Inc. 2012
*
* Authors:
* Alex Williamson <alex.williamson@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Based on qemu-kvm device-assignment:
* Adapted for KVM by Qumranet.
* Copyright (c) 2007, Neocleus, Alex Novik (alex@neocleus.com)
* Copyright (c) 2007, Neocleus, Guy Zana (guy@neocleus.com)
* Copyright (C) 2008, Qumranet, Amit Shah (amit.shah@qumranet.com)
* Copyright (C) 2008, Red Hat, Amit Shah (amit.shah@redhat.com)
* Copyright (C) 2008, IBM, Muli Ben-Yehuda (muli@il.ibm.com)
*/
#include "qemu/osdep.h"
#include <sys/ioctl.h>
#ifdef CONFIG_KVM
#include <linux/kvm.h>
#endif
#include <linux/vfio.h>
#include "hw/vfio/vfio-common.h"
#include "hw/vfio/vfio.h"
#include "exec/address-spaces.h"
#include "exec/memory.h"
#include "exec/ram_addr.h"
#include "hw/hw.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/range.h"
#include "sysemu/kvm.h"
#include "sysemu/reset.h"
#include "sysemu/runstate.h"
#include "trace.h"
#include "qapi/error.h"
#include "migration/migration.h"
#include "migration/misc.h"
#include "migration/blocker.h"
#include "sysemu/tpm.h"
VFIOGroupList vfio_group_list =
QLIST_HEAD_INITIALIZER(vfio_group_list);
static QLIST_HEAD(, VFIOAddressSpace) vfio_address_spaces =
QLIST_HEAD_INITIALIZER(vfio_address_spaces);
#ifdef CONFIG_KVM
/*
* We have a single VFIO pseudo device per KVM VM. Once created it lives
* for the life of the VM. Closing the file descriptor only drops our
* reference to it and the device's reference to kvm. Therefore once
* initialized, this file descriptor is only released on QEMU exit and
* we'll re-use it should another vfio device be attached before then.
*/
static int vfio_kvm_device_fd = -1;
#endif
/*
* Common VFIO interrupt disable
*/
void vfio_disable_irqindex(VFIODevice *vbasedev, int index)
{
struct vfio_irq_set irq_set = {
.argsz = sizeof(irq_set),
.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER,
.index = index,
.start = 0,
.count = 0,
};
ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
}
void vfio_unmask_single_irqindex(VFIODevice *vbasedev, int index)
{
struct vfio_irq_set irq_set = {
.argsz = sizeof(irq_set),
.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK,
.index = index,
.start = 0,
.count = 1,
};
ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
}
void vfio_mask_single_irqindex(VFIODevice *vbasedev, int index)
{
struct vfio_irq_set irq_set = {
.argsz = sizeof(irq_set),
.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK,
.index = index,
.start = 0,
.count = 1,
};
ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
}
static inline const char *action_to_str(int action)
{
switch (action) {
case VFIO_IRQ_SET_ACTION_MASK:
return "MASK";
case VFIO_IRQ_SET_ACTION_UNMASK:
return "UNMASK";
case VFIO_IRQ_SET_ACTION_TRIGGER:
return "TRIGGER";
default:
return "UNKNOWN ACTION";
}
}
static const char *index_to_str(VFIODevice *vbasedev, int index)
{
if (vbasedev->type != VFIO_DEVICE_TYPE_PCI) {
return NULL;
}
switch (index) {
case VFIO_PCI_INTX_IRQ_INDEX:
return "INTX";
case VFIO_PCI_MSI_IRQ_INDEX:
return "MSI";
case VFIO_PCI_MSIX_IRQ_INDEX:
return "MSIX";
case VFIO_PCI_ERR_IRQ_INDEX:
return "ERR";
case VFIO_PCI_REQ_IRQ_INDEX:
return "REQ";
default:
return NULL;
}
}
static int vfio_ram_block_discard_disable(VFIOContainer *container, bool state)
{
switch (container->iommu_type) {
case VFIO_TYPE1v2_IOMMU:
case VFIO_TYPE1_IOMMU:
/*
* We support coordinated discarding of RAM via the RamDiscardManager.
*/
return ram_block_uncoordinated_discard_disable(state);
default:
/*
* VFIO_SPAPR_TCE_IOMMU most probably works just fine with
* RamDiscardManager, however, it is completely untested.
*
* VFIO_SPAPR_TCE_v2_IOMMU with "DMA memory preregistering" does
* completely the opposite of managing mapping/pinning dynamically as
* required by RamDiscardManager. We would have to special-case sections
* with a RamDiscardManager.
*/
return ram_block_discard_disable(state);
}
}
int vfio_set_irq_signaling(VFIODevice *vbasedev, int index, int subindex,
int action, int fd, Error **errp)
{
struct vfio_irq_set *irq_set;
int argsz, ret = 0;
const char *name;
int32_t *pfd;
argsz = sizeof(*irq_set) + sizeof(*pfd);
irq_set = g_malloc0(argsz);
irq_set->argsz = argsz;
irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | action;
irq_set->index = index;
irq_set->start = subindex;
irq_set->count = 1;
pfd = (int32_t *)&irq_set->data;
*pfd = fd;
if (ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
ret = -errno;
}
g_free(irq_set);
if (!ret) {
return 0;
}
error_setg_errno(errp, -ret, "VFIO_DEVICE_SET_IRQS failure");
name = index_to_str(vbasedev, index);
if (name) {
error_prepend(errp, "%s-%d: ", name, subindex);
} else {
error_prepend(errp, "index %d-%d: ", index, subindex);
}
error_prepend(errp,
"Failed to %s %s eventfd signaling for interrupt ",
fd < 0 ? "tear down" : "set up", action_to_str(action));
return ret;
}
/*
* IO Port/MMIO - Beware of the endians, VFIO is always little endian
*/
void vfio_region_write(void *opaque, hwaddr addr,
uint64_t data, unsigned size)
{
VFIORegion *region = opaque;
VFIODevice *vbasedev = region->vbasedev;
union {
uint8_t byte;
uint16_t word;
uint32_t dword;
uint64_t qword;
} buf;
switch (size) {
case 1:
buf.byte = data;
break;
case 2:
buf.word = cpu_to_le16(data);
break;
case 4:
buf.dword = cpu_to_le32(data);
break;
case 8:
buf.qword = cpu_to_le64(data);
break;
default:
hw_error("vfio: unsupported write size, %u bytes", size);
break;
}
if (pwrite(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64
",%d) failed: %m",
__func__, vbasedev->name, region->nr,
addr, data, size);
}
trace_vfio_region_write(vbasedev->name, region->nr, addr, data, size);
/*
* A read or write to a BAR always signals an INTx EOI. This will
* do nothing if not pending (including not in INTx mode). We assume
* that a BAR access is in response to an interrupt and that BAR
* accesses will service the interrupt. Unfortunately, we don't know
* which access will service the interrupt, so we're potentially
* getting quite a few host interrupts per guest interrupt.
*/
vbasedev->ops->vfio_eoi(vbasedev);
}
uint64_t vfio_region_read(void *opaque,
hwaddr addr, unsigned size)
{
VFIORegion *region = opaque;
VFIODevice *vbasedev = region->vbasedev;
union {
uint8_t byte;
uint16_t word;
uint32_t dword;
uint64_t qword;
} buf;
uint64_t data = 0;
if (pread(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %m",
__func__, vbasedev->name, region->nr,
addr, size);
return (uint64_t)-1;
}
switch (size) {
case 1:
data = buf.byte;
break;
case 2:
data = le16_to_cpu(buf.word);
break;
case 4:
data = le32_to_cpu(buf.dword);
break;
case 8:
data = le64_to_cpu(buf.qword);
break;
default:
hw_error("vfio: unsupported read size, %u bytes", size);
break;
}
trace_vfio_region_read(vbasedev->name, region->nr, addr, size, data);
/* Same as write above */
vbasedev->ops->vfio_eoi(vbasedev);
return data;
}
const MemoryRegionOps vfio_region_ops = {
.read = vfio_region_read,
.write = vfio_region_write,
.endianness = DEVICE_LITTLE_ENDIAN,
.valid = {
.min_access_size = 1,
.max_access_size = 8,
},
.impl = {
.min_access_size = 1,
.max_access_size = 8,
},
};
/*
* Device state interfaces
*/
bool vfio_mig_active(void)
{
VFIOGroup *group;
VFIODevice *vbasedev;
if (QLIST_EMPTY(&vfio_group_list)) {
return false;
}
QLIST_FOREACH(group, &vfio_group_list, next) {
QLIST_FOREACH(vbasedev, &group->device_list, next) {
if (vbasedev->migration_blocker) {
return false;
}
}
}
return true;
}
static Error *multiple_devices_migration_blocker;
static unsigned int vfio_migratable_device_num(void)
{
VFIOGroup *group;
VFIODevice *vbasedev;
unsigned int device_num = 0;
QLIST_FOREACH(group, &vfio_group_list, next) {
QLIST_FOREACH(vbasedev, &group->device_list, next) {
if (vbasedev->migration) {
device_num++;
}
}
}
return device_num;
}
int vfio_block_multiple_devices_migration(Error **errp)
{
int ret;
if (multiple_devices_migration_blocker ||
vfio_migratable_device_num() <= 1) {
return 0;
}
error_setg(&multiple_devices_migration_blocker,
"Migration is currently not supported with multiple "
"VFIO devices");
ret = migrate_add_blocker(multiple_devices_migration_blocker, errp);
if (ret < 0) {
error_free(multiple_devices_migration_blocker);
multiple_devices_migration_blocker = NULL;
}
return ret;
}
void vfio_unblock_multiple_devices_migration(void)
{
if (!multiple_devices_migration_blocker ||
vfio_migratable_device_num() > 1) {
return;
}
migrate_del_blocker(multiple_devices_migration_blocker);
error_free(multiple_devices_migration_blocker);
multiple_devices_migration_blocker = NULL;
}
static bool vfio_devices_all_dirty_tracking(VFIOContainer *container)
{
VFIOGroup *group;
VFIODevice *vbasedev;
MigrationState *ms = migrate_get_current();
if (!migration_is_setup_or_active(ms->state)) {
return false;
}
QLIST_FOREACH(group, &container->group_list, container_next) {
QLIST_FOREACH(vbasedev, &group->device_list, next) {
VFIOMigration *migration = vbasedev->migration;
if (!migration) {
return false;
}
if (!migration->v2 &&
(vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF) &&
(migration->device_state_v1 & VFIO_DEVICE_STATE_V1_RUNNING)) {
return false;
}
if (migration->v2 &&
vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF &&
migration->device_state == VFIO_DEVICE_STATE_RUNNING) {
return false;
}
}
}
return true;
}
/*
* Check if all VFIO devices are running and migration is active, which is
* essentially equivalent to the migration being in pre-copy phase.
*/
static bool vfio_devices_all_running_and_mig_active(VFIOContainer *container)
{
VFIOGroup *group;
VFIODevice *vbasedev;
if (!migration_is_active(migrate_get_current())) {
return false;
}
QLIST_FOREACH(group, &container->group_list, container_next) {
QLIST_FOREACH(vbasedev, &group->device_list, next) {
VFIOMigration *migration = vbasedev->migration;
if (!migration) {
return false;
}
if (!migration->v2 &&
migration->device_state_v1 & VFIO_DEVICE_STATE_V1_RUNNING) {
continue;
}
if (migration->v2 &&
migration->device_state == VFIO_DEVICE_STATE_RUNNING) {
continue;
} else {
return false;
}
}
}
return true;
}
static int vfio_dma_unmap_bitmap(VFIOContainer *container,
hwaddr iova, ram_addr_t size,
IOMMUTLBEntry *iotlb)
{
struct vfio_iommu_type1_dma_unmap *unmap;
struct vfio_bitmap *bitmap;
uint64_t pages = REAL_HOST_PAGE_ALIGN(size) / qemu_real_host_page_size();
int ret;
unmap = g_malloc0(sizeof(*unmap) + sizeof(*bitmap));
unmap->argsz = sizeof(*unmap) + sizeof(*bitmap);
unmap->iova = iova;
unmap->size = size;
unmap->flags |= VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP;
bitmap = (struct vfio_bitmap *)&unmap->data;
/*
* cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of
* qemu_real_host_page_size to mark those dirty. Hence set bitmap_pgsize
* to qemu_real_host_page_size.
*/
bitmap->pgsize = qemu_real_host_page_size();
bitmap->size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) /
BITS_PER_BYTE;
if (bitmap->size > container->max_dirty_bitmap_size) {
error_report("UNMAP: Size of bitmap too big 0x%"PRIx64,
(uint64_t)bitmap->size);
ret = -E2BIG;
goto unmap_exit;
}
bitmap->data = g_try_malloc0(bitmap->size);
if (!bitmap->data) {
ret = -ENOMEM;
goto unmap_exit;
}
ret = ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, unmap);
if (!ret) {
cpu_physical_memory_set_dirty_lebitmap((unsigned long *)bitmap->data,
iotlb->translated_addr, pages);
} else {
error_report("VFIO_UNMAP_DMA with DIRTY_BITMAP : %m");
}
g_free(bitmap->data);
unmap_exit:
g_free(unmap);
return ret;
}
/*
* DMA - Mapping and unmapping for the "type1" IOMMU interface used on x86
*/
static int vfio_dma_unmap(VFIOContainer *container,
hwaddr iova, ram_addr_t size,
IOMMUTLBEntry *iotlb)
{
struct vfio_iommu_type1_dma_unmap unmap = {
.argsz = sizeof(unmap),
.flags = 0,
.iova = iova,
.size = size,
};
if (iotlb && container->dirty_pages_supported &&
vfio_devices_all_running_and_mig_active(container)) {
return vfio_dma_unmap_bitmap(container, iova, size, iotlb);
}
while (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
/*
* The type1 backend has an off-by-one bug in the kernel (71a7d3d78e3c
* v4.15) where an overflow in its wrap-around check prevents us from
* unmapping the last page of the address space. Test for the error
* condition and re-try the unmap excluding the last page. The
* expectation is that we've never mapped the last page anyway and this
* unmap request comes via vIOMMU support which also makes it unlikely
* that this page is used. This bug was introduced well after type1 v2
* support was introduced, so we shouldn't need to test for v1. A fix
* is queued for kernel v5.0 so this workaround can be removed once
* affected kernels are sufficiently deprecated.
*/
if (errno == EINVAL && unmap.size && !(unmap.iova + unmap.size) &&
container->iommu_type == VFIO_TYPE1v2_IOMMU) {
trace_vfio_dma_unmap_overflow_workaround();
unmap.size -= 1ULL << ctz64(container->pgsizes);
continue;
}
error_report("VFIO_UNMAP_DMA failed: %s", strerror(errno));
return -errno;
}
if (iotlb && vfio_devices_all_running_and_mig_active(container)) {
cpu_physical_memory_set_dirty_range(iotlb->translated_addr, size,
tcg_enabled() ? DIRTY_CLIENTS_ALL :
DIRTY_CLIENTS_NOCODE);
}
return 0;
}
static int vfio_dma_map(VFIOContainer *container, hwaddr iova,
ram_addr_t size, void *vaddr, bool readonly)
{
struct vfio_iommu_type1_dma_map map = {
.argsz = sizeof(map),
.flags = VFIO_DMA_MAP_FLAG_READ,
.vaddr = (__u64)(uintptr_t)vaddr,
.iova = iova,
.size = size,
};
if (!readonly) {
map.flags |= VFIO_DMA_MAP_FLAG_WRITE;
}
/*
* Try the mapping, if it fails with EBUSY, unmap the region and try
* again. This shouldn't be necessary, but we sometimes see it in
* the VGA ROM space.
*/
if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0 ||
(errno == EBUSY && vfio_dma_unmap(container, iova, size, NULL) == 0 &&
ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0)) {
return 0;
}
error_report("VFIO_MAP_DMA failed: %s", strerror(errno));
return -errno;
}
static void vfio_host_win_add(VFIOContainer *container,
hwaddr min_iova, hwaddr max_iova,
uint64_t iova_pgsizes)
{
VFIOHostDMAWindow *hostwin;
QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
if (ranges_overlap(hostwin->min_iova,
hostwin->max_iova - hostwin->min_iova + 1,
min_iova,
max_iova - min_iova + 1)) {
hw_error("%s: Overlapped IOMMU are not enabled", __func__);
}
}
hostwin = g_malloc0(sizeof(*hostwin));
hostwin->min_iova = min_iova;
hostwin->max_iova = max_iova;
hostwin->iova_pgsizes = iova_pgsizes;
QLIST_INSERT_HEAD(&container->hostwin_list, hostwin, hostwin_next);
}
static int vfio_host_win_del(VFIOContainer *container, hwaddr min_iova,
hwaddr max_iova)
{
VFIOHostDMAWindow *hostwin;
QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
if (hostwin->min_iova == min_iova && hostwin->max_iova == max_iova) {
QLIST_REMOVE(hostwin, hostwin_next);
g_free(hostwin);
return 0;
}
}
return -1;
}
static bool vfio_listener_skipped_section(MemoryRegionSection *section)
{
return (!memory_region_is_ram(section->mr) &&
!memory_region_is_iommu(section->mr)) ||
memory_region_is_protected(section->mr) ||
/*
* Sizing an enabled 64-bit BAR can cause spurious mappings to
* addresses in the upper part of the 64-bit address space. These
* are never accessed by the CPU and beyond the address width of
* some IOMMU hardware. TODO: VFIO should tell us the IOMMU width.
*/
section->offset_within_address_space & (1ULL << 63);
}
/* Called with rcu_read_lock held. */
static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
ram_addr_t *ram_addr, bool *read_only)
{
bool ret, mr_has_discard_manager;
ret = memory_get_xlat_addr(iotlb, vaddr, ram_addr, read_only,
&mr_has_discard_manager);
if (ret && mr_has_discard_manager) {
/*
* Malicious VMs might trigger discarding of IOMMU-mapped memory. The
* pages will remain pinned inside vfio until unmapped, resulting in a
* higher memory consumption than expected. If memory would get
* populated again later, there would be an inconsistency between pages
* pinned by vfio and pages seen by QEMU. This is the case until
* unmapped from the IOMMU (e.g., during device reset).
*
* With malicious guests, we really only care about pinning more memory
* than expected. RLIMIT_MEMLOCK set for the user/process can never be
* exceeded and can be used to mitigate this problem.
*/
warn_report_once("Using vfio with vIOMMUs and coordinated discarding of"
" RAM (e.g., virtio-mem) works, however, malicious"
" guests can trigger pinning of more memory than"
" intended via an IOMMU. It's possible to mitigate "
" by setting/adjusting RLIMIT_MEMLOCK.");
}
return ret;
}
static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
{
VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n);
VFIOContainer *container = giommu->container;
hwaddr iova = iotlb->iova + giommu->iommu_offset;
void *vaddr;
int ret;
trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP",
iova, iova + iotlb->addr_mask);
if (iotlb->target_as != &address_space_memory) {
error_report("Wrong target AS \"%s\", only system memory is allowed",
iotlb->target_as->name ? iotlb->target_as->name : "none");
return;
}
rcu_read_lock();
if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
bool read_only;
if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only)) {
goto out;
}
/*
* vaddr is only valid until rcu_read_unlock(). But after
* vfio_dma_map has set up the mapping the pages will be
* pinned by the kernel. This makes sure that the RAM backend
* of vaddr will always be there, even if the memory object is
* destroyed and its backing memory munmap-ed.
*/
ret = vfio_dma_map(container, iova,
iotlb->addr_mask + 1, vaddr,
read_only);
if (ret) {
error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
"0x%"HWADDR_PRIx", %p) = %d (%m)",
container, iova,
iotlb->addr_mask + 1, vaddr, ret);
}
} else {
ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1, iotlb);
if (ret) {
error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
"0x%"HWADDR_PRIx") = %d (%m)",
container, iova,
iotlb->addr_mask + 1, ret);
}
}
out:
rcu_read_unlock();
}
static void vfio_ram_discard_notify_discard(RamDiscardListener *rdl,
MemoryRegionSection *section)
{
VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener,
listener);
const hwaddr size = int128_get64(section->size);
const hwaddr iova = section->offset_within_address_space;
int ret;
/* Unmap with a single call. */
ret = vfio_dma_unmap(vrdl->container, iova, size , NULL);
if (ret) {
error_report("%s: vfio_dma_unmap() failed: %s", __func__,
strerror(-ret));
}
}
static int vfio_ram_discard_notify_populate(RamDiscardListener *rdl,
MemoryRegionSection *section)
{
VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener,
listener);
const hwaddr end = section->offset_within_region +
int128_get64(section->size);
hwaddr start, next, iova;
void *vaddr;
int ret;
/*
* Map in (aligned within memory region) minimum granularity, so we can
* unmap in minimum granularity later.
*/
for (start = section->offset_within_region; start < end; start = next) {
next = ROUND_UP(start + 1, vrdl->granularity);
next = MIN(next, end);
iova = start - section->offset_within_region +
section->offset_within_address_space;
vaddr = memory_region_get_ram_ptr(section->mr) + start;
ret = vfio_dma_map(vrdl->container, iova, next - start,
vaddr, section->readonly);
if (ret) {
/* Rollback */
vfio_ram_discard_notify_discard(rdl, section);
return ret;
}
}
return 0;
}
static void vfio_register_ram_discard_listener(VFIOContainer *container,
MemoryRegionSection *section)
{
RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
VFIORamDiscardListener *vrdl;
/* Ignore some corner cases not relevant in practice. */
g_assert(QEMU_IS_ALIGNED(section->offset_within_region, TARGET_PAGE_SIZE));
g_assert(QEMU_IS_ALIGNED(section->offset_within_address_space,
TARGET_PAGE_SIZE));
g_assert(QEMU_IS_ALIGNED(int128_get64(section->size), TARGET_PAGE_SIZE));
vrdl = g_new0(VFIORamDiscardListener, 1);
vrdl->container = container;
vrdl->mr = section->mr;
vrdl->offset_within_address_space = section->offset_within_address_space;
vrdl->size = int128_get64(section->size);
vrdl->granularity = ram_discard_manager_get_min_granularity(rdm,
section->mr);
g_assert(vrdl->granularity && is_power_of_2(vrdl->granularity));
g_assert(container->pgsizes &&
vrdl->granularity >= 1ULL << ctz64(container->pgsizes));
ram_discard_listener_init(&vrdl->listener,
vfio_ram_discard_notify_populate,
vfio_ram_discard_notify_discard, true);
ram_discard_manager_register_listener(rdm, &vrdl->listener, section);
QLIST_INSERT_HEAD(&container->vrdl_list, vrdl, next);
/*
* Sanity-check if we have a theoretically problematic setup where we could
* exceed the maximum number of possible DMA mappings over time. We assume
* that each mapped section in the same address space as a RamDiscardManager
* section consumes exactly one DMA mapping, with the exception of
* RamDiscardManager sections; i.e., we don't expect to have gIOMMU sections
* in the same address space as RamDiscardManager sections.
*
* We assume that each section in the address space consumes one memslot.
* We take the number of KVM memory slots as a best guess for the maximum
* number of sections in the address space we could have over time,
* also consuming DMA mappings.
*/
if (container->dma_max_mappings) {
unsigned int vrdl_count = 0, vrdl_mappings = 0, max_memslots = 512;
#ifdef CONFIG_KVM
if (kvm_enabled()) {
max_memslots = kvm_get_max_memslots();
}
#endif
QLIST_FOREACH(vrdl, &container->vrdl_list, next) {
hwaddr start, end;
start = QEMU_ALIGN_DOWN(vrdl->offset_within_address_space,
vrdl->granularity);
end = ROUND_UP(vrdl->offset_within_address_space + vrdl->size,
vrdl->granularity);
vrdl_mappings += (end - start) / vrdl->granularity;
vrdl_count++;
}
if (vrdl_mappings + max_memslots - vrdl_count >
container->dma_max_mappings) {
warn_report("%s: possibly running out of DMA mappings. E.g., try"
" increasing the 'block-size' of virtio-mem devies."
" Maximum possible DMA mappings: %d, Maximum possible"
" memslots: %d", __func__, container->dma_max_mappings,
max_memslots);
}
}
}
static void vfio_unregister_ram_discard_listener(VFIOContainer *container,
MemoryRegionSection *section)
{
RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
VFIORamDiscardListener *vrdl = NULL;
QLIST_FOREACH(vrdl, &container->vrdl_list, next) {
if (vrdl->mr == section->mr &&
vrdl->offset_within_address_space ==
section->offset_within_address_space) {
break;
}
}
if (!vrdl) {
hw_error("vfio: Trying to unregister missing RAM discard listener");
}
ram_discard_manager_unregister_listener(rdm, &vrdl->listener);
QLIST_REMOVE(vrdl, next);
g_free(vrdl);
}
static bool vfio_known_safe_misalignment(MemoryRegionSection *section)
{
MemoryRegion *mr = section->mr;
if (!TPM_IS_CRB(mr->owner)) {
return false;
}
/* this is a known safe misaligned region, just trace for debug purpose */
trace_vfio_known_safe_misalignment(memory_region_name(mr),
section->offset_within_address_space,
section->offset_within_region,
qemu_real_host_page_size());
return true;
}
static void vfio_listener_region_add(MemoryListener *listener,
MemoryRegionSection *section)
{
VFIOContainer *container = container_of(listener, VFIOContainer, listener);
hwaddr iova, end;
Int128 llend, llsize;
void *vaddr;
int ret;
VFIOHostDMAWindow *hostwin;
bool hostwin_found;
Error *err = NULL;
if (vfio_listener_skipped_section(section)) {
trace_vfio_listener_region_add_skip(
section->offset_within_address_space,
section->offset_within_address_space +
int128_get64(int128_sub(section->size, int128_one())));
return;
}
if (unlikely((section->offset_within_address_space &
~qemu_real_host_page_mask()) !=
(section->offset_within_region & ~qemu_real_host_page_mask()))) {
if (!vfio_known_safe_misalignment(section)) {
error_report("%s received unaligned region %s iova=0x%"PRIx64
" offset_within_region=0x%"PRIx64
" qemu_real_host_page_size=0x%"PRIxPTR,
__func__, memory_region_name(section->mr),
section->offset_within_address_space,
section->offset_within_region,
qemu_real_host_page_size());
}
return;
}
iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space);
llend = int128_make64(section->offset_within_address_space);
llend = int128_add(llend, section->size);
llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask()));
if (int128_ge(int128_make64(iova), llend)) {
if (memory_region_is_ram_device(section->mr)) {
trace_vfio_listener_region_add_no_dma_map(
memory_region_name(section->mr),
section->offset_within_address_space,
int128_getlo(section->size),
qemu_real_host_page_size());
}
return;
}
end = int128_get64(int128_sub(llend, int128_one()));
if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
hwaddr pgsize = 0;
/* For now intersections are not allowed, we may relax this later */
QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
if (ranges_overlap(hostwin->min_iova,
hostwin->max_iova - hostwin->min_iova + 1,
section->offset_within_address_space,
int128_get64(section->size))) {
error_setg(&err,
"region [0x%"PRIx64",0x%"PRIx64"] overlaps with existing"
"host DMA window [0x%"PRIx64",0x%"PRIx64"]",
section->offset_within_address_space,
section->offset_within_address_space +
int128_get64(section->size) - 1,
hostwin->min_iova, hostwin->max_iova);
goto fail;
}
}
ret = vfio_spapr_create_window(container, section, &pgsize);
if (ret) {
error_setg_errno(&err, -ret, "Failed to create SPAPR window");
goto fail;
}
vfio_host_win_add(container, section->offset_within_address_space,
section->offset_within_address_space +
int128_get64(section->size) - 1, pgsize);
#ifdef CONFIG_KVM
if (kvm_enabled()) {
VFIOGroup *group;
IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
struct kvm_vfio_spapr_tce param;
struct kvm_device_attr attr = {
.group = KVM_DEV_VFIO_GROUP,
.attr = KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE,
.addr = (uint64_t)(unsigned long)&param,
};
if (!memory_region_iommu_get_attr(iommu_mr, IOMMU_ATTR_SPAPR_TCE_FD,
&param.tablefd)) {
QLIST_FOREACH(group, &container->group_list, container_next) {
param.groupfd = group->fd;
if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
error_report("vfio: failed to setup fd %d "
"for a group with fd %d: %s",
param.tablefd, param.groupfd,
strerror(errno));
return;
}
trace_vfio_spapr_group_attach(param.groupfd, param.tablefd);
}
}
}
#endif
}
hostwin_found = false;
QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
if (hostwin->min_iova <= iova && end <= hostwin->max_iova) {
hostwin_found = true;
break;
}
}
if (!hostwin_found) {
error_setg(&err, "Container %p can't map guest IOVA region"
" 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx, container, iova, end);
goto fail;
}
memory_region_ref(section->mr);
if (memory_region_is_iommu(section->mr)) {
VFIOGuestIOMMU *giommu;
IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
int iommu_idx;
trace_vfio_listener_region_add_iommu(iova, end);
/*
* FIXME: For VFIO iommu types which have KVM acceleration to
* avoid bouncing all map/unmaps through qemu this way, this
* would be the right place to wire that up (tell the KVM
* device emulation the VFIO iommu handles to use).
*/
giommu = g_malloc0(sizeof(*giommu));
giommu->iommu_mr = iommu_mr;
giommu->iommu_offset = section->offset_within_address_space -
section->offset_within_region;
giommu->container = container;
llend = int128_add(int128_make64(section->offset_within_region),
section->size);
llend = int128_sub(llend, int128_one());
iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
MEMTXATTRS_UNSPECIFIED);
iommu_notifier_init(&giommu->n, vfio_iommu_map_notify,
IOMMU_NOTIFIER_IOTLB_EVENTS,
section->offset_within_region,
int128_get64(llend),
iommu_idx);
ret = memory_region_iommu_set_page_size_mask(giommu->iommu_mr,
container->pgsizes,
&err);
if (ret) {
g_free(giommu);
goto fail;
}
ret = memory_region_register_iommu_notifier(section->mr, &giommu->n,
&err);
if (ret) {
g_free(giommu);
goto fail;
}
QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
memory_region_iommu_replay(giommu->iommu_mr, &giommu->n);
return;
}
/* Here we assume that memory_region_is_ram(section->mr)==true */
/*
* For RAM memory regions with a RamDiscardManager, we only want to map the
* actually populated parts - and update the mapping whenever we're notified
* about changes.
*/
if (memory_region_has_ram_discard_manager(section->mr)) {
vfio_register_ram_discard_listener(container, section);
return;
}
vaddr = memory_region_get_ram_ptr(section->mr) +
section->offset_within_region +
(iova - section->offset_within_address_space);
trace_vfio_listener_region_add_ram(iova, end, vaddr);
llsize = int128_sub(llend, int128_make64(iova));
if (memory_region_is_ram_device(section->mr)) {
hwaddr pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1;
if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) {
trace_vfio_listener_region_add_no_dma_map(
memory_region_name(section->mr),
section->offset_within_address_space,
int128_getlo(section->size),
pgmask + 1);
return;
}
}
ret = vfio_dma_map(container, iova, int128_get64(llsize),
vaddr, section->readonly);
if (ret) {
error_setg(&err, "vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
"0x%"HWADDR_PRIx", %p) = %d (%m)",
container, iova, int128_get64(llsize), vaddr, ret);
if (memory_region_is_ram_device(section->mr)) {
/* Allow unexpected mappings not to be fatal for RAM devices */
error_report_err(err);
return;
}
goto fail;
}
return;
fail:
if (memory_region_is_ram_device(section->mr)) {
error_report("failed to vfio_dma_map. pci p2p may not work");
return;
}
/*
* On the initfn path, store the first error in the container so we
* can gracefully fail. Runtime, there's not much we can do other
* than throw a hardware error.
*/
if (!container->initialized) {
if (!container->error) {
error_propagate_prepend(&container->error, err,
"Region %s: ",
memory_region_name(section->mr));
} else {
error_free(err);
}
} else {
error_report_err(err);
hw_error("vfio: DMA mapping failed, unable to continue");
}
}
static void vfio_listener_region_del(MemoryListener *listener,
MemoryRegionSection *section)
{
VFIOContainer *container = container_of(listener, VFIOContainer, listener);
hwaddr iova, end;
Int128 llend, llsize;
int ret;
bool try_unmap = true;
if (vfio_listener_skipped_section(section)) {
trace_vfio_listener_region_del_skip(
section->offset_within_address_space,
section->offset_within_address_space +
int128_get64(int128_sub(section->size, int128_one())));
return;
}
if (unlikely((section->offset_within_address_space &
~qemu_real_host_page_mask()) !=
(section->offset_within_region & ~qemu_real_host_page_mask()))) {
if (!vfio_known_safe_misalignment(section)) {
error_report("%s received unaligned region %s iova=0x%"PRIx64
" offset_within_region=0x%"PRIx64
" qemu_real_host_page_size=0x%"PRIxPTR,
__func__, memory_region_name(section->mr),
section->offset_within_address_space,
section->offset_within_region,
qemu_real_host_page_size());
}
return;
}
if (memory_region_is_iommu(section->mr)) {
VFIOGuestIOMMU *giommu;
QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
if (MEMORY_REGION(giommu->iommu_mr) == section->mr &&
giommu->n.start == section->offset_within_region) {
memory_region_unregister_iommu_notifier(section->mr,
&giommu->n);
QLIST_REMOVE(giommu, giommu_next);
g_free(giommu);
break;
}
}
/*
* FIXME: We assume the one big unmap below is adequate to
* remove any individual page mappings in the IOMMU which
* might have been copied into VFIO. This works for a page table
* based IOMMU where a big unmap flattens a large range of IO-PTEs.
* That may not be true for all IOMMU types.
*/
}
iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space);
llend = int128_make64(section->offset_within_address_space);
llend = int128_add(llend, section->size);
llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask()));
if (int128_ge(int128_make64(iova), llend)) {
return;
}
end = int128_get64(int128_sub(llend, int128_one()));
llsize = int128_sub(llend, int128_make64(iova));
trace_vfio_listener_region_del(iova, end);
if (memory_region_is_ram_device(section->mr)) {
hwaddr pgmask;
VFIOHostDMAWindow *hostwin;
bool hostwin_found = false;
QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
if (hostwin->min_iova <= iova && end <= hostwin->max_iova) {
hostwin_found = true;
break;
}
}
assert(hostwin_found); /* or region_add() would have failed */
pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1;
try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask));
} else if (memory_region_has_ram_discard_manager(section->mr)) {
vfio_unregister_ram_discard_listener(container, section);
/* Unregistering will trigger an unmap. */
try_unmap = false;
}
if (try_unmap) {
if (int128_eq(llsize, int128_2_64())) {
/* The unmap ioctl doesn't accept a full 64-bit span. */
llsize = int128_rshift(llsize, 1);
ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL);
if (ret) {
error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
"0x%"HWADDR_PRIx") = %d (%m)",
container, iova, int128_get64(llsize), ret);
}
iova += int128_get64(llsize);
}
ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL);
if (ret) {
error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
"0x%"HWADDR_PRIx") = %d (%m)",
container, iova, int128_get64(llsize), ret);
}
}
memory_region_unref(section->mr);
if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
vfio_spapr_remove_window(container,
section->offset_within_address_space);
if (vfio_host_win_del(container,
section->offset_within_address_space,
section->offset_within_address_space +
int128_get64(section->size) - 1) < 0) {
hw_error("%s: Cannot delete missing window at %"HWADDR_PRIx,
__func__, section->offset_within_address_space);
}
}
}
static void vfio_set_dirty_page_tracking(VFIOContainer *container, bool start)
{
int ret;
struct vfio_iommu_type1_dirty_bitmap dirty = {
.argsz = sizeof(dirty),
};
if (!container->dirty_pages_supported) {
return;
}
if (start) {
dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_START;
} else {
dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP;
}
ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, &dirty);
if (ret) {
error_report("Failed to set dirty tracking flag 0x%x errno: %d",
dirty.flags, errno);
}
}
static void vfio_listener_log_global_start(MemoryListener *listener)
{
VFIOContainer *container = container_of(listener, VFIOContainer, listener);
vfio_set_dirty_page_tracking(container, true);
}
static void vfio_listener_log_global_stop(MemoryListener *listener)
{
VFIOContainer *container = container_of(listener, VFIOContainer, listener);
vfio_set_dirty_page_tracking(container, false);
}
static int vfio_get_dirty_bitmap(VFIOContainer *container, uint64_t iova,
uint64_t size, ram_addr_t ram_addr)
{
struct vfio_iommu_type1_dirty_bitmap *dbitmap;
struct vfio_iommu_type1_dirty_bitmap_get *range;
uint64_t pages;
int ret;
if (!container->dirty_pages_supported) {
cpu_physical_memory_set_dirty_range(ram_addr, size,
tcg_enabled() ? DIRTY_CLIENTS_ALL :
DIRTY_CLIENTS_NOCODE);
return 0;
}
dbitmap = g_malloc0(sizeof(*dbitmap) + sizeof(*range));
dbitmap->argsz = sizeof(*dbitmap) + sizeof(*range);
dbitmap->flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
range = (struct vfio_iommu_type1_dirty_bitmap_get *)&dbitmap->data;
range->iova = iova;
range->size = size;
/*
* cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of
* qemu_real_host_page_size to mark those dirty. Hence set bitmap's pgsize
* to qemu_real_host_page_size.
*/
range->bitmap.pgsize = qemu_real_host_page_size();
pages = REAL_HOST_PAGE_ALIGN(range->size) / qemu_real_host_page_size();
range->bitmap.size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) /
BITS_PER_BYTE;
range->bitmap.data = g_try_malloc0(range->bitmap.size);
if (!range->bitmap.data) {
ret = -ENOMEM;
goto err_out;
}
ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, dbitmap);
if (ret) {
error_report("Failed to get dirty bitmap for iova: 0x%"PRIx64
" size: 0x%"PRIx64" err: %d", (uint64_t)range->iova,
(uint64_t)range->size, errno);
goto err_out;
}
cpu_physical_memory_set_dirty_lebitmap((unsigned long *)range->bitmap.data,
ram_addr, pages);
trace_vfio_get_dirty_bitmap(container->fd, range->iova, range->size,
range->bitmap.size, ram_addr);
err_out:
g_free(range->bitmap.data);
g_free(dbitmap);
return ret;
}
typedef struct {
IOMMUNotifier n;
VFIOGuestIOMMU *giommu;
} vfio_giommu_dirty_notifier;
static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
{
vfio_giommu_dirty_notifier *gdn = container_of(n,
vfio_giommu_dirty_notifier, n);
VFIOGuestIOMMU *giommu = gdn->giommu;
VFIOContainer *container = giommu->container;
hwaddr iova = iotlb->iova + giommu->iommu_offset;
ram_addr_t translated_addr;
trace_vfio_iommu_map_dirty_notify(iova, iova + iotlb->addr_mask);
if (iotlb->target_as != &address_space_memory) {
error_report("Wrong target AS \"%s\", only system memory is allowed",
iotlb->target_as->name ? iotlb->target_as->name : "none");
return;
}
rcu_read_lock();
if (vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL)) {
int ret;
ret = vfio_get_dirty_bitmap(container, iova, iotlb->addr_mask + 1,
translated_addr);
if (ret) {
error_report("vfio_iommu_map_dirty_notify(%p, 0x%"HWADDR_PRIx", "
"0x%"HWADDR_PRIx") = %d (%m)",
container, iova,
iotlb->addr_mask + 1, ret);
}
}
rcu_read_unlock();
}
static int vfio_ram_discard_get_dirty_bitmap(MemoryRegionSection *section,
void *opaque)
{
const hwaddr size = int128_get64(section->size);
const hwaddr iova = section->offset_within_address_space;
const ram_addr_t ram_addr = memory_region_get_ram_addr(section->mr) +
section->offset_within_region;
VFIORamDiscardListener *vrdl = opaque;
/*
* Sync the whole mapped region (spanning multiple individual mappings)
* in one go.
*/
return vfio_get_dirty_bitmap(vrdl->container, iova, size, ram_addr);
}
static int vfio_sync_ram_discard_listener_dirty_bitmap(VFIOContainer *container,
MemoryRegionSection *section)
{
RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
VFIORamDiscardListener *vrdl = NULL;
QLIST_FOREACH(vrdl, &container->vrdl_list, next) {
if (vrdl->mr == section->mr &&
vrdl->offset_within_address_space ==
section->offset_within_address_space) {
break;
}
}
if (!vrdl) {
hw_error("vfio: Trying to sync missing RAM discard listener");
}
/*
* We only want/can synchronize the bitmap for actually mapped parts -
* which correspond to populated parts. Replay all populated parts.
*/
return ram_discard_manager_replay_populated(rdm, section,
vfio_ram_discard_get_dirty_bitmap,
&vrdl);
}
static int vfio_sync_dirty_bitmap(VFIOContainer *container,
MemoryRegionSection *section)
{
ram_addr_t ram_addr;
if (memory_region_is_iommu(section->mr)) {
VFIOGuestIOMMU *giommu;
QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
if (MEMORY_REGION(giommu->iommu_mr) == section->mr &&
giommu->n.start == section->offset_within_region) {
Int128 llend;
vfio_giommu_dirty_notifier gdn = { .giommu = giommu };
int idx = memory_region_iommu_attrs_to_index(giommu->iommu_mr,
MEMTXATTRS_UNSPECIFIED);
llend = int128_add(int128_make64(section->offset_within_region),
section->size);
llend = int128_sub(llend, int128_one());
iommu_notifier_init(&gdn.n,
vfio_iommu_map_dirty_notify,
IOMMU_NOTIFIER_MAP,
section->offset_within_region,
int128_get64(llend),
idx);
memory_region_iommu_replay(giommu->iommu_mr, &gdn.n);
break;
}
}
return 0;
} else if (memory_region_has_ram_discard_manager(section->mr)) {
return vfio_sync_ram_discard_listener_dirty_bitmap(container, section);
}
ram_addr = memory_region_get_ram_addr(section->mr) +
section->offset_within_region;
return vfio_get_dirty_bitmap(container,
REAL_HOST_PAGE_ALIGN(section->offset_within_address_space),
int128_get64(section->size), ram_addr);
}
static void vfio_listener_log_sync(MemoryListener *listener,
MemoryRegionSection *section)
{
VFIOContainer *container = container_of(listener, VFIOContainer, listener);
if (vfio_listener_skipped_section(section)) {
return;
}
if (vfio_devices_all_dirty_tracking(container)) {
vfio_sync_dirty_bitmap(container, section);
}
}
static const MemoryListener vfio_memory_listener = {
.name = "vfio",
.region_add = vfio_listener_region_add,
.region_del = vfio_listener_region_del,
.log_global_start = vfio_listener_log_global_start,
.log_global_stop = vfio_listener_log_global_stop,
.log_sync = vfio_listener_log_sync,
};
static void vfio_listener_release(VFIOContainer *container)
{
memory_listener_unregister(&container->listener);
if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
memory_listener_unregister(&container->prereg_listener);
}
}
static struct vfio_info_cap_header *
vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id)
{
struct vfio_info_cap_header *hdr;
for (hdr = ptr + cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
if (hdr->id == id) {
return hdr;
}
}
return NULL;
}
struct vfio_info_cap_header *
vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id)
{
if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) {
return NULL;
}
return vfio_get_cap((void *)info, info->cap_offset, id);
}
static struct vfio_info_cap_header *
vfio_get_iommu_type1_info_cap(struct vfio_iommu_type1_info *info, uint16_t id)
{
if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) {
return NULL;
}
return vfio_get_cap((void *)info, info->cap_offset, id);
}
struct vfio_info_cap_header *
vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id)
{
if (!(info->flags & VFIO_DEVICE_FLAGS_CAPS)) {
return NULL;
}
return vfio_get_cap((void *)info, info->cap_offset, id);
}
bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info,
unsigned int *avail)
{
struct vfio_info_cap_header *hdr;
struct vfio_iommu_type1_info_dma_avail *cap;
/* If the capability cannot be found, assume no DMA limiting */
hdr = vfio_get_iommu_type1_info_cap(info,
VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL);
if (hdr == NULL) {
return false;
}
if (avail != NULL) {
cap = (void *) hdr;
*avail = cap->avail;
}
return true;
}
static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
struct vfio_region_info *info)
{
struct vfio_info_cap_header *hdr;
struct vfio_region_info_cap_sparse_mmap *sparse;
int i, j;
hdr = vfio_get_region_info_cap(info, VFIO_REGION_INFO_CAP_SPARSE_MMAP);
if (!hdr) {
return -ENODEV;
}
sparse = container_of(hdr, struct vfio_region_info_cap_sparse_mmap, header);
trace_vfio_region_sparse_mmap_header(region->vbasedev->name,
region->nr, sparse->nr_areas);
region->mmaps = g_new0(VFIOMmap, sparse->nr_areas);
for (i = 0, j = 0; i < sparse->nr_areas; i++) {
if (sparse->areas[i].size) {
trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset,
sparse->areas[i].offset +
sparse->areas[i].size - 1);
region->mmaps[j].offset = sparse->areas[i].offset;
region->mmaps[j].size = sparse->areas[i].size;
j++;
}
}
region->nr_mmaps = j;
region->mmaps = g_realloc(region->mmaps, j * sizeof(VFIOMmap));
return 0;
}
int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
int index, const char *name)
{
struct vfio_region_info *info;
int ret;
ret = vfio_get_region_info(vbasedev, index, &info);
if (ret) {
return ret;
}
region->vbasedev = vbasedev;
region->flags = info->flags;
region->size = info->size;
region->fd_offset = info->offset;
region->nr = index;
if (region->size) {
region->mem = g_new0(MemoryRegion, 1);
memory_region_init_io(region->mem, obj, &vfio_region_ops,
region, name, region->size);
if (!vbasedev->no_mmap &&
region->flags & VFIO_REGION_INFO_FLAG_MMAP) {
ret = vfio_setup_region_sparse_mmaps(region, info);
if (ret) {
region->nr_mmaps = 1;
region->mmaps = g_new0(VFIOMmap, region->nr_mmaps);
region->mmaps[0].offset = 0;
region->mmaps[0].size = region->size;
}
}
}
g_free(info);
trace_vfio_region_setup(vbasedev->name, index, name,
region->flags, region->fd_offset, region->size);
return 0;
}
static void vfio_subregion_unmap(VFIORegion *region, int index)
{
trace_vfio_region_unmap(memory_region_name(&region->mmaps[index].mem),
region->mmaps[index].offset,
region->mmaps[index].offset +
region->mmaps[index].size - 1);
memory_region_del_subregion(region->mem, &region->mmaps[index].mem);
munmap(region->mmaps[index].mmap, region->mmaps[index].size);
object_unparent(OBJECT(&region->mmaps[index].mem));
region->mmaps[index].mmap = NULL;
}
int vfio_region_mmap(VFIORegion *region)
{
int i, prot = 0;
char *name;
if (!region->mem) {
return 0;
}
prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0;
prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0;
for (i = 0; i < region->nr_mmaps; i++) {
region->mmaps[i].mmap = mmap(NULL, region->mmaps[i].size, prot,
MAP_SHARED, region->vbasedev->fd,
region->fd_offset +
region->mmaps[i].offset);
if (region->mmaps[i].mmap == MAP_FAILED) {
int ret = -errno;
trace_vfio_region_mmap_fault(memory_region_name(region->mem), i,
region->fd_offset +
region->mmaps[i].offset,
region->fd_offset +
region->mmaps[i].offset +
region->mmaps[i].size - 1, ret);
region->mmaps[i].mmap = NULL;
for (i--; i >= 0; i--) {
vfio_subregion_unmap(region, i);
}
return ret;
}
name = g_strdup_printf("%s mmaps[%d]",
memory_region_name(region->mem), i);
memory_region_init_ram_device_ptr(&region->mmaps[i].mem,
memory_region_owner(region->mem),
name, region->mmaps[i].size,
region->mmaps[i].mmap);
g_free(name);
memory_region_add_subregion(region->mem, region->mmaps[i].offset,
&region->mmaps[i].mem);
trace_vfio_region_mmap(memory_region_name(&region->mmaps[i].mem),
region->mmaps[i].offset,
region->mmaps[i].offset +
region->mmaps[i].size - 1);
}
return 0;
}
void vfio_region_unmap(VFIORegion *region)
{
int i;
if (!region->mem) {
return;
}
for (i = 0; i < region->nr_mmaps; i++) {
if (region->mmaps[i].mmap) {
vfio_subregion_unmap(region, i);
}
}
}
void vfio_region_exit(VFIORegion *region)
{
int i;
if (!region->mem) {
return;
}
for (i = 0; i < region->nr_mmaps; i++) {
if (region->mmaps[i].mmap) {
memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
}
}
trace_vfio_region_exit(region->vbasedev->name, region->nr);
}
void vfio_region_finalize(VFIORegion *region)
{
int i;
if (!region->mem) {
return;
}
for (i = 0; i < region->nr_mmaps; i++) {
if (region->mmaps[i].mmap) {
munmap(region->mmaps[i].mmap, region->mmaps[i].size);
object_unparent(OBJECT(&region->mmaps[i].mem));
}
}
object_unparent(OBJECT(region->mem));
g_free(region->mem);
g_free(region->mmaps);
trace_vfio_region_finalize(region->vbasedev->name, region->nr);
region->mem = NULL;
region->mmaps = NULL;
region->nr_mmaps = 0;
region->size = 0;
region->flags = 0;
region->nr = 0;
}
void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled)
{
int i;
if (!region->mem) {
return;
}
for (i = 0; i < region->nr_mmaps; i++) {
if (region->mmaps[i].mmap) {
memory_region_set_enabled(&region->mmaps[i].mem, enabled);
}
}
trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem),
enabled);
}
void vfio_reset_handler(void *opaque)
{
VFIOGroup *group;
VFIODevice *vbasedev;
QLIST_FOREACH(group, &vfio_group_list, next) {
QLIST_FOREACH(vbasedev, &group->device_list, next) {
if (vbasedev->dev->realized) {
vbasedev->ops->vfio_compute_needs_reset(vbasedev);
}
}
}
QLIST_FOREACH(group, &vfio_group_list, next) {
QLIST_FOREACH(vbasedev, &group->device_list, next) {
if (vbasedev->dev->realized && vbasedev->needs_reset) {
vbasedev->ops->vfio_hot_reset_multi(vbasedev);
}
}
}
}
static void vfio_kvm_device_add_group(VFIOGroup *group)
{
#ifdef CONFIG_KVM
struct kvm_device_attr attr = {
.group = KVM_DEV_VFIO_GROUP,
.attr = KVM_DEV_VFIO_GROUP_ADD,
.addr = (uint64_t)(unsigned long)&group->fd,
};
if (!kvm_enabled()) {
return;
}
if (vfio_kvm_device_fd < 0) {
struct kvm_create_device cd = {
.type = KVM_DEV_TYPE_VFIO,
};
if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
error_report("Failed to create KVM VFIO device: %m");
return;
}
vfio_kvm_device_fd = cd.fd;
}
if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
error_report("Failed to add group %d to KVM VFIO device: %m",
group->groupid);
}
#endif
}
static void vfio_kvm_device_del_group(VFIOGroup *group)
{
#ifdef CONFIG_KVM
struct kvm_device_attr attr = {
.group = KVM_DEV_VFIO_GROUP,
.attr = KVM_DEV_VFIO_GROUP_DEL,
.addr = (uint64_t)(unsigned long)&group->fd,
};
if (vfio_kvm_device_fd < 0) {
return;
}
if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
error_report("Failed to remove group %d from KVM VFIO device: %m",
group->groupid);
}
#endif
}
static VFIOAddressSpace *vfio_get_address_space(AddressSpace *as)
{
VFIOAddressSpace *space;
QLIST_FOREACH(space, &vfio_address_spaces, list) {
if (space->as == as) {
return space;
}
}
/* No suitable VFIOAddressSpace, create a new one */
space = g_malloc0(sizeof(*space));
space->as = as;
QLIST_INIT(&space->containers);
QLIST_INSERT_HEAD(&vfio_address_spaces, space, list);
return space;
}
static void vfio_put_address_space(VFIOAddressSpace *space)
{
if (QLIST_EMPTY(&space->containers)) {
QLIST_REMOVE(space, list);
g_free(space);
}
}
/*
* vfio_get_iommu_type - selects the richest iommu_type (v2 first)
*/
static int vfio_get_iommu_type(VFIOContainer *container,
Error **errp)
{
int iommu_types[] = { VFIO_TYPE1v2_IOMMU, VFIO_TYPE1_IOMMU,
VFIO_SPAPR_TCE_v2_IOMMU, VFIO_SPAPR_TCE_IOMMU };
int i;
for (i = 0; i < ARRAY_SIZE(iommu_types); i++) {
if (ioctl(container->fd, VFIO_CHECK_EXTENSION, iommu_types[i])) {
return iommu_types[i];
}
}
error_setg(errp, "No available IOMMU models");
return -EINVAL;
}
static int vfio_init_container(VFIOContainer *container, int group_fd,
Error **errp)
{
int iommu_type, ret;
iommu_type = vfio_get_iommu_type(container, errp);
if (iommu_type < 0) {
return iommu_type;
}
ret = ioctl(group_fd, VFIO_GROUP_SET_CONTAINER, &container->fd);
if (ret) {
error_setg_errno(errp, errno, "Failed to set group container");
return -errno;
}
while (ioctl(container->fd, VFIO_SET_IOMMU, iommu_type)) {
if (iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
/*
* On sPAPR, despite the IOMMU subdriver always advertises v1 and
* v2, the running platform may not support v2 and there is no
* way to guess it until an IOMMU group gets added to the container.
* So in case it fails with v2, try v1 as a fallback.
*/
iommu_type = VFIO_SPAPR_TCE_IOMMU;
continue;
}
error_setg_errno(errp, errno, "Failed to set iommu for container");
return -errno;
}
container->iommu_type = iommu_type;
return 0;
}
static int vfio_get_iommu_info(VFIOContainer *container,
struct vfio_iommu_type1_info **info)
{
size_t argsz = sizeof(struct vfio_iommu_type1_info);
*info = g_new0(struct vfio_iommu_type1_info, 1);
again:
(*info)->argsz = argsz;
if (ioctl(container->fd, VFIO_IOMMU_GET_INFO, *info)) {
g_free(*info);
*info = NULL;
return -errno;
}
if (((*info)->argsz > argsz)) {
argsz = (*info)->argsz;
*info = g_realloc(*info, argsz);
goto again;
}
return 0;
}
static struct vfio_info_cap_header *
vfio_get_iommu_info_cap(struct vfio_iommu_type1_info *info, uint16_t id)
{
struct vfio_info_cap_header *hdr;
void *ptr = info;
if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) {
return NULL;
}
for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
if (hdr->id == id) {
return hdr;
}
}
return NULL;
}
static void vfio_get_iommu_info_migration(VFIOContainer *container,
struct vfio_iommu_type1_info *info)
{
struct vfio_info_cap_header *hdr;
struct vfio_iommu_type1_info_cap_migration *cap_mig;
hdr = vfio_get_iommu_info_cap(info, VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION);
if (!hdr) {
return;
}
cap_mig = container_of(hdr, struct vfio_iommu_type1_info_cap_migration,
header);
/*
* cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of
* qemu_real_host_page_size to mark those dirty.
*/
if (cap_mig->pgsize_bitmap & qemu_real_host_page_size()) {
container->dirty_pages_supported = true;
container->max_dirty_bitmap_size = cap_mig->max_dirty_bitmap_size;
container->dirty_pgsizes = cap_mig->pgsize_bitmap;
}
}
static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
Error **errp)
{
VFIOContainer *container;
int ret, fd;
VFIOAddressSpace *space;
space = vfio_get_address_space(as);
/*
* VFIO is currently incompatible with discarding of RAM insofar as the
* madvise to purge (zap) the page from QEMU's address space does not
* interact with the memory API and therefore leaves stale virtual to
* physical mappings in the IOMMU if the page was previously pinned. We
* therefore set discarding broken for each group added to a container,
* whether the container is used individually or shared. This provides
* us with options to allow devices within a group to opt-in and allow
* discarding, so long as it is done consistently for a group (for instance
* if the device is an mdev device where it is known that the host vendor
* driver will never pin pages outside of the working set of the guest
* driver, which would thus not be discarding candidates).
*
* The first opportunity to induce pinning occurs here where we attempt to
* attach the group to existing containers within the AddressSpace. If any
* pages are already zapped from the virtual address space, such as from
* previous discards, new pinning will cause valid mappings to be
* re-established. Likewise, when the overall MemoryListener for a new
* container is registered, a replay of mappings within the AddressSpace
* will occur, re-establishing any previously zapped pages as well.
*
* Especially virtio-balloon is currently only prevented from discarding
* new memory, it will not yet set ram_block_discard_set_required() and
* therefore, neither stops us here or deals with the sudden memory
* consumption of inflated memory.
*
* We do support discarding of memory coordinated via the RamDiscardManager
* with some IOMMU types. vfio_ram_block_discard_disable() handles the
* details once we know which type of IOMMU we are using.
*/
QLIST_FOREACH(container, &space->containers, next) {
if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
ret = vfio_ram_block_discard_disable(container, true);
if (ret) {
error_setg_errno(errp, -ret,
"Cannot set discarding of RAM broken");
if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER,
&container->fd)) {
error_report("vfio: error disconnecting group %d from"
" container", group->groupid);
}
return ret;
}
group->container = container;
QLIST_INSERT_HEAD(&container->group_list, group, container_next);
vfio_kvm_device_add_group(group);
return 0;
}
}
fd = qemu_open_old("/dev/vfio/vfio", O_RDWR);
if (fd < 0) {
error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio");
ret = -errno;
goto put_space_exit;
}
ret = ioctl(fd, VFIO_GET_API_VERSION);
if (ret != VFIO_API_VERSION) {
error_setg(errp, "supported vfio version: %d, "
"reported version: %d", VFIO_API_VERSION, ret);
ret = -EINVAL;
goto close_fd_exit;
}
container = g_malloc0(sizeof(*container));
container->space = space;
container->fd = fd;
container->error = NULL;
container->dirty_pages_supported = false;
container->dma_max_mappings = 0;
QLIST_INIT(&container->giommu_list);
QLIST_INIT(&container->hostwin_list);
QLIST_INIT(&container->vrdl_list);
ret = vfio_init_container(container, group->fd, errp);
if (ret) {
goto free_container_exit;
}
ret = vfio_ram_block_discard_disable(container, true);
if (ret) {
error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken");
goto free_container_exit;
}
switch (container->iommu_type) {
case VFIO_TYPE1v2_IOMMU:
case VFIO_TYPE1_IOMMU:
{
struct vfio_iommu_type1_info *info;
ret = vfio_get_iommu_info(container, &info);
if (ret) {
error_setg_errno(errp, -ret, "Failed to get VFIO IOMMU info");
goto enable_discards_exit;
}
if (info->flags & VFIO_IOMMU_INFO_PGSIZES) {
container->pgsizes = info->iova_pgsizes;
} else {
container->pgsizes = qemu_real_host_page_size();
}
if (!vfio_get_info_dma_avail(info, &container->dma_max_mappings)) {
container->dma_max_mappings = 65535;
}
vfio_get_iommu_info_migration(container, info);
g_free(info);
/*
* FIXME: We should parse VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE
* information to get the actual window extent rather than assume
* a 64-bit IOVA address space.
*/
vfio_host_win_add(container, 0, (hwaddr)-1, container->pgsizes);
break;
}
case VFIO_SPAPR_TCE_v2_IOMMU:
case VFIO_SPAPR_TCE_IOMMU:
{
struct vfio_iommu_spapr_tce_info info;
bool v2 = container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU;
/*
* The host kernel code implementing VFIO_IOMMU_DISABLE is called
* when container fd is closed so we do not call it explicitly
* in this file.
*/
if (!v2) {
ret = ioctl(fd, VFIO_IOMMU_ENABLE);
if (ret) {
error_setg_errno(errp, errno, "failed to enable container");
ret = -errno;
goto enable_discards_exit;
}
} else {
container->prereg_listener = vfio_prereg_listener;
memory_listener_register(&container->prereg_listener,
&address_space_memory);
if (container->error) {
memory_listener_unregister(&container->prereg_listener);
ret = -1;
error_propagate_prepend(errp, container->error,
"RAM memory listener initialization failed: ");
goto enable_discards_exit;
}
}
info.argsz = sizeof(info);
ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info);
if (ret) {
error_setg_errno(errp, errno,
"VFIO_IOMMU_SPAPR_TCE_GET_INFO failed");
ret = -errno;
if (v2) {
memory_listener_unregister(&container->prereg_listener);
}
goto enable_discards_exit;
}
if (v2) {
container->pgsizes = info.ddw.pgsizes;
/*
* There is a default window in just created container.
* To make region_add/del simpler, we better remove this
* window now and let those iommu_listener callbacks
* create/remove them when needed.
*/
ret = vfio_spapr_remove_window(container, info.dma32_window_start);
if (ret) {
error_setg_errno(errp, -ret,
"failed to remove existing window");
goto enable_discards_exit;
}
} else {
/* The default table uses 4K pages */
container->pgsizes = 0x1000;
vfio_host_win_add(container, info.dma32_window_start,
info.dma32_window_start +
info.dma32_window_size - 1,
0x1000);
}
}
}
vfio_kvm_device_add_group(group);
QLIST_INIT(&container->group_list);
QLIST_INSERT_HEAD(&space->containers, container, next);
group->container = container;
QLIST_INSERT_HEAD(&container->group_list, group, container_next);
container->listener = vfio_memory_listener;
memory_listener_register(&container->listener, container->space->as);
if (container->error) {
ret = -1;
error_propagate_prepend(errp, container->error,
"memory listener initialization failed: ");
goto listener_release_exit;
}
container->initialized = true;
return 0;
listener_release_exit:
QLIST_REMOVE(group, container_next);
QLIST_REMOVE(container, next);
vfio_kvm_device_del_group(group);
vfio_listener_release(container);
enable_discards_exit:
vfio_ram_block_discard_disable(container, false);
free_container_exit:
g_free(container);
close_fd_exit:
close(fd);
put_space_exit:
vfio_put_address_space(space);
return ret;
}
static void vfio_disconnect_container(VFIOGroup *group)
{
VFIOContainer *container = group->container;
QLIST_REMOVE(group, container_next);
group->container = NULL;
/*
* Explicitly release the listener first before unset container,
* since unset may destroy the backend container if it's the last
* group.
*/
if (QLIST_EMPTY(&container->group_list)) {
vfio_listener_release(container);
}
if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) {
error_report("vfio: error disconnecting group %d from container",
group->groupid);
}
if (QLIST_EMPTY(&container->group_list)) {
VFIOAddressSpace *space = container->space;
VFIOGuestIOMMU *giommu, *tmp;
VFIOHostDMAWindow *hostwin, *next;
QLIST_REMOVE(container, next);
QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
memory_region_unregister_iommu_notifier(
MEMORY_REGION(giommu->iommu_mr), &giommu->n);
QLIST_REMOVE(giommu, giommu_next);
g_free(giommu);
}
QLIST_FOREACH_SAFE(hostwin, &container->hostwin_list, hostwin_next,
next) {
QLIST_REMOVE(hostwin, hostwin_next);
g_free(hostwin);
}
trace_vfio_disconnect_container(container->fd);
close(container->fd);
g_free(container);
vfio_put_address_space(space);
}
}
VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp)
{
VFIOGroup *group;
char path[32];
struct vfio_group_status status = { .argsz = sizeof(status) };
QLIST_FOREACH(group, &vfio_group_list, next) {
if (group->groupid == groupid) {
/* Found it. Now is it already in the right context? */
if (group->container->space->as == as) {
return group;
} else {
error_setg(errp, "group %d used in multiple address spaces",
group->groupid);
return NULL;
}
}
}
group = g_malloc0(sizeof(*group));
snprintf(path, sizeof(path), "/dev/vfio/%d", groupid);
group->fd = qemu_open_old(path, O_RDWR);
if (group->fd < 0) {
error_setg_errno(errp, errno, "failed to open %s", path);
goto free_group_exit;
}
if (ioctl(group->fd, VFIO_GROUP_GET_STATUS, &status)) {
error_setg_errno(errp, errno, "failed to get group %d status", groupid);
goto close_fd_exit;
}
if (!(status.flags & VFIO_GROUP_FLAGS_VIABLE)) {
error_setg(errp, "group %d is not viable", groupid);
error_append_hint(errp,
"Please ensure all devices within the iommu_group "
"are bound to their vfio bus driver.\n");
goto close_fd_exit;
}
group->groupid = groupid;
QLIST_INIT(&group->device_list);
if (vfio_connect_container(group, as, errp)) {
error_prepend(errp, "failed to setup container for group %d: ",
groupid);
goto close_fd_exit;
}
if (QLIST_EMPTY(&vfio_group_list)) {
qemu_register_reset(vfio_reset_handler, NULL);
}
QLIST_INSERT_HEAD(&vfio_group_list, group, next);
return group;
close_fd_exit:
close(group->fd);
free_group_exit:
g_free(group);
return NULL;
}
void vfio_put_group(VFIOGroup *group)
{
if (!group || !QLIST_EMPTY(&group->device_list)) {
return;
}
if (!group->ram_block_discard_allowed) {
vfio_ram_block_discard_disable(group->container, false);
}
vfio_kvm_device_del_group(group);
vfio_disconnect_container(group);
QLIST_REMOVE(group, next);
trace_vfio_put_group(group->fd);
close(group->fd);
g_free(group);
if (QLIST_EMPTY(&vfio_group_list)) {
qemu_unregister_reset(vfio_reset_handler, NULL);
}
}
int vfio_get_device(VFIOGroup *group, const char *name,
VFIODevice *vbasedev, Error **errp)
{
struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
int ret, fd;
fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
if (fd < 0) {
error_setg_errno(errp, errno, "error getting device from group %d",
group->groupid);
error_append_hint(errp,
"Verify all devices in group %d are bound to vfio-<bus> "
"or pci-stub and not already in use\n", group->groupid);
return fd;
}
ret = ioctl(fd, VFIO_DEVICE_GET_INFO, &dev_info);
if (ret) {
error_setg_errno(errp, errno, "error getting device info");
close(fd);
return ret;
}
/*
* Set discarding of RAM as not broken for this group if the driver knows
* the device operates compatibly with discarding. Setting must be
* consistent per group, but since compatibility is really only possible
* with mdev currently, we expect singleton groups.
*/
if (vbasedev->ram_block_discard_allowed !=
group->ram_block_discard_allowed) {
if (!QLIST_EMPTY(&group->device_list)) {
error_setg(errp, "Inconsistent setting of support for discarding "
"RAM (e.g., balloon) within group");
close(fd);
return -1;
}
if (!group->ram_block_discard_allowed) {
group->ram_block_discard_allowed = true;
vfio_ram_block_discard_disable(group->container, false);
}
}
vbasedev->fd = fd;
vbasedev->group = group;
QLIST_INSERT_HEAD(&group->device_list, vbasedev, next);
vbasedev->num_irqs = dev_info.num_irqs;
vbasedev->num_regions = dev_info.num_regions;
vbasedev->flags = dev_info.flags;
trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions,
dev_info.num_irqs);
vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
return 0;
}
void vfio_put_base_device(VFIODevice *vbasedev)
{
if (!vbasedev->group) {
return;
}
QLIST_REMOVE(vbasedev, next);
vbasedev->group = NULL;
trace_vfio_put_base_device(vbasedev->fd);
close(vbasedev->fd);
}
int vfio_get_region_info(VFIODevice *vbasedev, int index,
struct vfio_region_info **info)
{
size_t argsz = sizeof(struct vfio_region_info);
*info = g_malloc0(argsz);
(*info)->index = index;
retry:
(*info)->argsz = argsz;
if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
g_free(*info);
*info = NULL;
return -errno;
}
if ((*info)->argsz > argsz) {
argsz = (*info)->argsz;
*info = g_realloc(*info, argsz);
goto retry;
}
return 0;
}
int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
uint32_t subtype, struct vfio_region_info **info)
{
int i;
for (i = 0; i < vbasedev->num_regions; i++) {
struct vfio_info_cap_header *hdr;
struct vfio_region_info_cap_type *cap_type;
if (vfio_get_region_info(vbasedev, i, info)) {
continue;
}
hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE);
if (!hdr) {
g_free(*info);
continue;
}
cap_type = container_of(hdr, struct vfio_region_info_cap_type, header);
trace_vfio_get_dev_region(vbasedev->name, i,
cap_type->type, cap_type->subtype);
if (cap_type->type == type && cap_type->subtype == subtype) {
return 0;
}
g_free(*info);
}
*info = NULL;
return -ENODEV;
}
bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
{
struct vfio_region_info *info = NULL;
bool ret = false;
if (!vfio_get_region_info(vbasedev, region, &info)) {
if (vfio_get_region_info_cap(info, cap_type)) {
ret = true;
}
g_free(info);
}
return ret;
}
/*
* Interfaces for IBM EEH (Enhanced Error Handling)
*/
static bool vfio_eeh_container_ok(VFIOContainer *container)
{
/*
* As of 2016-03-04 (linux-4.5) the host kernel EEH/VFIO
* implementation is broken if there are multiple groups in a
* container. The hardware works in units of Partitionable
* Endpoints (== IOMMU groups) and the EEH operations naively
* iterate across all groups in the container, without any logic
* to make sure the groups have their state synchronized. For
* certain operations (ENABLE) that might be ok, until an error
* occurs, but for others (GET_STATE) it's clearly broken.
*/
/*
* XXX Once fixed kernels exist, test for them here
*/
if (QLIST_EMPTY(&container->group_list)) {
return false;
}
if (QLIST_NEXT(QLIST_FIRST(&container->group_list), container_next)) {
return false;
}
return true;
}
static int vfio_eeh_container_op(VFIOContainer *container, uint32_t op)
{
struct vfio_eeh_pe_op pe_op = {
.argsz = sizeof(pe_op),
.op = op,
};
int ret;
if (!vfio_eeh_container_ok(container)) {
error_report("vfio/eeh: EEH_PE_OP 0x%x: "
"kernel requires a container with exactly one group", op);
return -EPERM;
}
ret = ioctl(container->fd, VFIO_EEH_PE_OP, &pe_op);
if (ret < 0) {
error_report("vfio/eeh: EEH_PE_OP 0x%x failed: %m", op);
return -errno;
}
return ret;
}
static VFIOContainer *vfio_eeh_as_container(AddressSpace *as)
{
VFIOAddressSpace *space = vfio_get_address_space(as);
VFIOContainer *container = NULL;
if (QLIST_EMPTY(&space->containers)) {
/* No containers to act on */
goto out;
}
container = QLIST_FIRST(&space->containers);
if (QLIST_NEXT(container, next)) {
/* We don't yet have logic to synchronize EEH state across
* multiple containers */
container = NULL;
goto out;
}
out:
vfio_put_address_space(space);
return container;
}
bool vfio_eeh_as_ok(AddressSpace *as)
{
VFIOContainer *container = vfio_eeh_as_container(as);
return (container != NULL) && vfio_eeh_container_ok(container);
}
int vfio_eeh_as_op(AddressSpace *as, uint32_t op)
{
VFIOContainer *container = vfio_eeh_as_container(as);
if (!container) {
return -ENODEV;
}
return vfio_eeh_container_op(container, op);
}
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