OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity
1140051624
qemu-e2k/hw/vfio/common.c
Eric Auger 5c08600547 vfio: Use a trace point when a RAM section cannot be DMA mapped 
Commit 567b5b309a ("vfio/pci: Relax DMA map errors for MMIO regions")
added an error message if a passed memory section address or size
is not aligned to the page size and thus cannot be DMA mapped.

This patch fixes the trace by printing the region name and the
memory region section offset within the address space (instead of
offset_within_region).

We also turn the error_report into a trace event. Indeed, In some
cases, the traces can be confusing to non expert end-users and
let think the use case does not work (whereas it works as before).

This is the case where a BAR is successively mapped at different
GPAs and its sections are not compatible with dma map. The listener
is called several times and traces are issued for each intermediate
mapping.  The end-user cannot easily match those GPAs against the
final GPA output by lscpi. So let's keep those information to
informed users. In mid term, the plan is to advise the user about
BAR relocation relevance.

Fixes: 567b5b309a ("vfio/pci: Relax DMA map errors for MMIO regions")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-04-05 10:48:52 -06:00

1582 lines
48 KiB
C
Raw Blame History

/*
* 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/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);
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);
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_notifier_init(&giommu->n, vfio_iommu_map_notify,
IOMMU_NOTIFIER_ALL,
section->offset_within_region,
int128_get64(llend));
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);
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);
} 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) {
/*
* 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 */
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:
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;
}
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;
}
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);
}
Reference in New Issue View Git Blame Copy Permalink