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qemu / qemu / 2852aafd9d05d97accd7a1d4df8ff25d9ac4cbfc / . / hw / vfio / common.c
blob: 3f31f80b1280f7533baaa87379bd883ec1731124 [file] [log] [blame]
/*
* 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 "hw/hw.h"
#include "qemu/error-report.h"
#include "qemu/range.h"
#include "sysemu/balloon.h"
#include "sysemu/kvm.h"
#include "trace.h"
#include "qapi/error.h"
struct vfio_group_head vfio_group_list =
QLIST_HEAD_INITIALIZER(vfio_group_list);
struct vfio_as_head 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);
}
/*
* 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, %d 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, %d 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,
},
};
/*
* 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)
{
struct vfio_iommu_type1_dma_unmap unmap = {
.argsz = sizeof(unmap),
.flags = 0,
.iova = iova,
.size = size,
};
if (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
error_report("VFIO_UNMAP_DMA: %d", -errno);
return -errno;
}
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) == 0 &&
ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0)) {
return 0;
}
error_report("VFIO_MAP_DMA: %d", -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);
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)) ||
/*
* 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_vaddr(IOMMUTLBEntry *iotlb, void **vaddr,
bool *read_only)
{
MemoryRegion *mr;
hwaddr xlat;
hwaddr len = iotlb->addr_mask + 1;
bool writable = iotlb->perm & IOMMU_WO;
/*
* The IOMMU TLB entry we have just covers translation through
* this IOMMU to its immediate target. We need to translate
* it the rest of the way through to memory.
*/
mr = address_space_translate(&address_space_memory,
iotlb->translated_addr,
&xlat, &len, writable,
MEMTXATTRS_UNSPECIFIED);
if (!memory_region_is_ram(mr)) {
error_report("iommu map to non memory area %"HWADDR_PRIx"",
xlat);
return false;
}
/*
* Translation truncates length to the IOMMU page size,
* check that it did not truncate too much.
*/
if (len & iotlb->addr_mask) {
error_report("iommu has granularity incompatible with target AS");
return false;
}
*vaddr = memory_region_get_ram_ptr(mr) + xlat;
*read_only = !writable || mr->readonly;
return true;
}
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;
bool read_only;
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) {
if (!vfio_get_vaddr(iotlb, &vaddr, &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);
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_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;
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 & ~TARGET_PAGE_MASK) !=
(section->offset_within_region & ~TARGET_PAGE_MASK))) {
error_report("%s received unaligned region", __func__);
return;
}
iova = TARGET_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(TARGET_PAGE_MASK));
if (int128_ge(int128_make64(iova), llend)) {
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))) {
ret = -1;
goto fail;
}
}
ret = vfio_spapr_create_window(container, section, &pgsize);
if (ret) {
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_report("vfio: IOMMU container %p can't map guest IOVA region"
" 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx,
container, iova, end);
ret = -EFAULT;
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 = 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_ALL,
section->offset_within_region,
int128_get64(llend),
iommu_idx);
QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
memory_region_register_iommu_notifier(section->mr, &giommu->n);
memory_region_iommu_replay(giommu->iommu, &giommu->n);
return;
}
/* Here we assume that memory_region_is_ram(section->mr)==true */
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_report("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 */
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) {
container->error = ret;
}
} else {
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 & ~TARGET_PAGE_MASK) !=
(section->offset_within_region & ~TARGET_PAGE_MASK))) {
error_report("%s received unaligned region", __func__);
return;
}
if (memory_region_is_iommu(section->mr)) {
VFIOGuestIOMMU *giommu;
QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
if (MEMORY_REGION(giommu->iommu) == 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 = TARGET_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(TARGET_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));
}
if (try_unmap) {
ret = vfio_dma_unmap(container, iova, int128_get64(llsize));
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 const MemoryListener vfio_memory_listener = {
.region_add = vfio_listener_region_add,
.region_del = vfio_listener_region_del,
};
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_region_info_cap(struct vfio_region_info *info, uint16_t id)
{
struct vfio_info_cap_header *hdr;
void *ptr = info;
if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) {
return NULL;
}
for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
if (hdr->id == id) {
return hdr;
}
}
return NULL;
}
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++) {
trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset,
sparse->areas[i].offset +
sparse->areas[i].size);
if (sparse->areas[i].size) {
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;
}
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--) {
memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
munmap(region->mmaps[i].mmap, region->mmaps[i].size);
object_unparent(OBJECT(&region->mmaps[i].mem));
region->mmaps[i].mmap = NULL;
}
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_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);
}
}
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 memory ballooning 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 add a balloon inhibit 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
* ballooning, 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 ballooning 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 a
* previous ballooning opt-in, 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.
*
* NB. Balloon inhibiting does not currently block operation of the
* balloon driver or revoke previously pinned pages, it only prevents
* calling madvise to modify the virtual mapping of ballooned pages.
*/
qemu_balloon_inhibit(true);
QLIST_FOREACH(container, &space->containers, next) {
if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
group->container = container;
QLIST_INSERT_HEAD(&container->group_list, group, container_next);
vfio_kvm_device_add_group(group);
return 0;
}
}
fd = qemu_open("/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;
QLIST_INIT(&container->giommu_list);
QLIST_INIT(&container->hostwin_list);
if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU) ||
ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU)) {
bool v2 = !!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU);
struct vfio_iommu_type1_info info;
ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd);
if (ret) {
error_setg_errno(errp, errno, "failed to set group container");
ret = -errno;
goto free_container_exit;
}
container->iommu_type = v2 ? VFIO_TYPE1v2_IOMMU : VFIO_TYPE1_IOMMU;
ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
if (ret) {
error_setg_errno(errp, errno, "failed to set iommu for container");
ret = -errno;
goto free_container_exit;
}
/*
* FIXME: This assumes that a Type1 IOMMU can map any 64-bit
* IOVA whatsoever. That's not actually true, but the current
* kernel interface doesn't tell us what it can map, and the
* existing Type1 IOMMUs generally support any IOVA we're
* going to actually try in practice.
*/
info.argsz = sizeof(info);
ret = ioctl(fd, VFIO_IOMMU_GET_INFO, &info);
/* Ignore errors */
if (ret || !(info.flags & VFIO_IOMMU_INFO_PGSIZES)) {
/* Assume 4k IOVA page size */
info.iova_pgsizes = 4096;
}
vfio_host_win_add(container, 0, (hwaddr)-1, info.iova_pgsizes);
container->pgsizes = info.iova_pgsizes;
} else if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_IOMMU) ||
ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_v2_IOMMU)) {
struct vfio_iommu_spapr_tce_info info;
bool v2 = !!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_v2_IOMMU);
ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd);
if (ret) {
error_setg_errno(errp, errno, "failed to set group container");
ret = -errno;
goto free_container_exit;
}
container->iommu_type =
v2 ? VFIO_SPAPR_TCE_v2_IOMMU : VFIO_SPAPR_TCE_IOMMU;
ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
if (ret) {
container->iommu_type = VFIO_SPAPR_TCE_IOMMU;
v2 = false;
ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
}
if (ret) {
error_setg_errno(errp, errno, "failed to set iommu for container");
ret = -errno;
goto free_container_exit;
}
/*
* 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 free_container_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 = container->error;
error_setg(errp,
"RAM memory listener initialization failed for container");
goto free_container_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 free_container_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 free_container_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);
}
} else {
error_setg(errp, "No available IOMMU models");
ret = -EINVAL;
goto free_container_exit;
}
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 = container->error;
error_setg_errno(errp, -ret,
"memory listener initialization failed for container");
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);
free_container_exit:
g_free(container);
close_fd_exit:
close(fd);
put_space_exit:
qemu_balloon_inhibit(false);
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;
QLIST_REMOVE(container, next);
QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
memory_region_unregister_iommu_notifier(
MEMORY_REGION(giommu->iommu), &giommu->n);
QLIST_REMOVE(giommu, giommu_next);
g_free(giommu);
}
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(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->balloon_allowed) {
qemu_balloon_inhibit(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;
}
/*
* Clear the balloon inhibitor for this group if the driver knows the
* device operates compatibly with ballooning. Setting must be consistent
* per group, but since compatibility is really only possible with mdev
* currently, we expect singleton groups.
*/
if (vbasedev->balloon_allowed != group->balloon_allowed) {
if (!QLIST_EMPTY(&group->device_list)) {
error_setg(errp,
"Inconsistent device balloon setting within group");
return -1;
}
if (!group->balloon_allowed) {
group->balloon_allowed = true;
qemu_balloon_inhibit(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);
}