blob: 47b040f1bcca7dd0b5cf052d941b43541e98a3c5 [file] [log] [blame]
/*
* DMA memory preregistration
*
* Authors:
* Alexey Kardashevskiy <aik@ozlabs.ru>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include <sys/ioctl.h>
#include <linux/vfio.h>
#ifdef CONFIG_KVM
#include <linux/kvm.h>
#endif
#include "sysemu/kvm.h"
#include "exec/address-spaces.h"
#include "hw/vfio/vfio-common.h"
#include "hw/hw.h"
#include "exec/ram_addr.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "trace.h"
typedef struct VFIOSpaprContainer {
VFIOContainer container;
MemoryListener prereg_listener;
QLIST_HEAD(, VFIOHostDMAWindow) hostwin_list;
} VFIOSpaprContainer;
static bool vfio_prereg_listener_skipped_section(MemoryRegionSection *section)
{
if (memory_region_is_iommu(section->mr)) {
hw_error("Cannot possibly preregister IOMMU memory");
}
return !memory_region_is_ram(section->mr) ||
memory_region_is_ram_device(section->mr);
}
static void *vfio_prereg_gpa_to_vaddr(MemoryRegionSection *section, hwaddr gpa)
{
return memory_region_get_ram_ptr(section->mr) +
section->offset_within_region +
(gpa - section->offset_within_address_space);
}
static void vfio_prereg_listener_region_add(MemoryListener *listener,
MemoryRegionSection *section)
{
VFIOSpaprContainer *scontainer = container_of(listener, VFIOSpaprContainer,
prereg_listener);
VFIOContainer *container = &scontainer->container;
VFIOContainerBase *bcontainer = &container->bcontainer;
const hwaddr gpa = section->offset_within_address_space;
hwaddr end;
int ret;
hwaddr page_mask = qemu_real_host_page_mask();
struct vfio_iommu_spapr_register_memory reg = {
.argsz = sizeof(reg),
.flags = 0,
};
if (vfio_prereg_listener_skipped_section(section)) {
trace_vfio_prereg_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 & ~page_mask) ||
(section->offset_within_region & ~page_mask) ||
(int128_get64(section->size) & ~page_mask))) {
error_report("%s received unaligned region", __func__);
return;
}
end = section->offset_within_address_space + int128_get64(section->size);
if (gpa >= end) {
return;
}
memory_region_ref(section->mr);
reg.vaddr = (uintptr_t) vfio_prereg_gpa_to_vaddr(section, gpa);
reg.size = end - gpa;
ret = ioctl(container->fd, VFIO_IOMMU_SPAPR_REGISTER_MEMORY, &reg);
trace_vfio_prereg_register(reg.vaddr, reg.size, ret ? -errno : 0);
if (ret) {
/*
* 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 (!bcontainer->initialized) {
if (!bcontainer->error) {
error_setg_errno(&bcontainer->error, -ret,
"Memory registering failed");
}
} else {
hw_error("vfio: Memory registering failed, unable to continue");
}
}
}
static void vfio_prereg_listener_region_del(MemoryListener *listener,
MemoryRegionSection *section)
{
VFIOSpaprContainer *scontainer = container_of(listener, VFIOSpaprContainer,
prereg_listener);
VFIOContainer *container = &scontainer->container;
const hwaddr gpa = section->offset_within_address_space;
hwaddr end;
int ret;
hwaddr page_mask = qemu_real_host_page_mask();
struct vfio_iommu_spapr_register_memory reg = {
.argsz = sizeof(reg),
.flags = 0,
};
if (vfio_prereg_listener_skipped_section(section)) {
trace_vfio_prereg_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 & ~page_mask) ||
(section->offset_within_region & ~page_mask) ||
(int128_get64(section->size) & ~page_mask))) {
error_report("%s received unaligned region", __func__);
return;
}
end = section->offset_within_address_space + int128_get64(section->size);
if (gpa >= end) {
return;
}
reg.vaddr = (uintptr_t) vfio_prereg_gpa_to_vaddr(section, gpa);
reg.size = end - gpa;
ret = ioctl(container->fd, VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY, &reg);
trace_vfio_prereg_unregister(reg.vaddr, reg.size, ret ? -errno : 0);
}
static const MemoryListener vfio_prereg_listener = {
.name = "vfio-pre-reg",
.region_add = vfio_prereg_listener_region_add,
.region_del = vfio_prereg_listener_region_del,
};
static void vfio_host_win_add(VFIOSpaprContainer *scontainer, hwaddr min_iova,
hwaddr max_iova, uint64_t iova_pgsizes)
{
VFIOHostDMAWindow *hostwin;
QLIST_FOREACH(hostwin, &scontainer->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(&scontainer->hostwin_list, hostwin, hostwin_next);
}
static int vfio_host_win_del(VFIOSpaprContainer *scontainer,
hwaddr min_iova, hwaddr max_iova)
{
VFIOHostDMAWindow *hostwin;
QLIST_FOREACH(hostwin, &scontainer->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 VFIOHostDMAWindow *vfio_find_hostwin(VFIOSpaprContainer *container,
hwaddr iova, hwaddr end)
{
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;
}
}
return hostwin_found ? hostwin : NULL;
}
static int vfio_spapr_remove_window(VFIOContainer *container,
hwaddr offset_within_address_space)
{
struct vfio_iommu_spapr_tce_remove remove = {
.argsz = sizeof(remove),
.start_addr = offset_within_address_space,
};
int ret;
ret = ioctl(container->fd, VFIO_IOMMU_SPAPR_TCE_REMOVE, &remove);
if (ret) {
error_report("Failed to remove window at %"PRIx64,
(uint64_t)remove.start_addr);
return -errno;
}
trace_vfio_spapr_remove_window(offset_within_address_space);
return 0;
}
static int vfio_spapr_create_window(VFIOContainer *container,
MemoryRegionSection *section,
hwaddr *pgsize)
{
int ret = 0;
VFIOContainerBase *bcontainer = &container->bcontainer;
IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
uint64_t pagesize = memory_region_iommu_get_min_page_size(iommu_mr), pgmask;
unsigned entries, bits_total, bits_per_level, max_levels;
struct vfio_iommu_spapr_tce_create create = { .argsz = sizeof(create) };
long rampagesize = qemu_minrampagesize();
/*
* The host might not support the guest supported IOMMU page size,
* so we will use smaller physical IOMMU pages to back them.
*/
if (pagesize > rampagesize) {
pagesize = rampagesize;
}
pgmask = bcontainer->pgsizes & (pagesize | (pagesize - 1));
pagesize = pgmask ? (1ULL << (63 - clz64(pgmask))) : 0;
if (!pagesize) {
error_report("Host doesn't support page size 0x%"PRIx64
", the supported mask is 0x%lx",
memory_region_iommu_get_min_page_size(iommu_mr),
bcontainer->pgsizes);
return -EINVAL;
}
/*
* 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).
*/
create.window_size = int128_get64(section->size);
create.page_shift = ctz64(pagesize);
/*
* SPAPR host supports multilevel TCE tables. We try to guess optimal
* levels number and if this fails (for example due to the host memory
* fragmentation), we increase levels. The DMA address structure is:
* rrrrrrrr rxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx iiiiiiii
* where:
* r = reserved (bits >= 55 are reserved in the existing hardware)
* i = IOMMU page offset (64K in this example)
* x = bits to index a TCE which can be split to equal chunks to index
* within the level.
* The aim is to split "x" to smaller possible number of levels.
*/
entries = create.window_size >> create.page_shift;
/* bits_total is number of "x" needed */
bits_total = ctz64(entries * sizeof(uint64_t));
/*
* bits_per_level is a safe guess of how much we can allocate per level:
* 8 is the current minimum for CONFIG_FORCE_MAX_ZONEORDER and MAX_ORDER
* is usually bigger than that.
* Below we look at qemu_real_host_page_size as TCEs are allocated from
* system pages.
*/
bits_per_level = ctz64(qemu_real_host_page_size()) + 8;
create.levels = bits_total / bits_per_level;
if (bits_total % bits_per_level) {
++create.levels;
}
max_levels = (64 - create.page_shift) / ctz64(qemu_real_host_page_size());
for ( ; create.levels <= max_levels; ++create.levels) {
ret = ioctl(container->fd, VFIO_IOMMU_SPAPR_TCE_CREATE, &create);
if (!ret) {
break;
}
}
if (ret) {
error_report("Failed to create a window, ret = %d (%m)", ret);
return -errno;
}
if (create.start_addr != section->offset_within_address_space) {
vfio_spapr_remove_window(container, create.start_addr);
error_report("Host doesn't support DMA window at %"HWADDR_PRIx", must be %"PRIx64,
section->offset_within_address_space,
(uint64_t)create.start_addr);
return -EINVAL;
}
trace_vfio_spapr_create_window(create.page_shift,
create.levels,
create.window_size,
create.start_addr);
*pgsize = pagesize;
return 0;
}
static bool
vfio_spapr_container_add_section_window(VFIOContainerBase *bcontainer,
MemoryRegionSection *section,
Error **errp)
{
VFIOContainer *container = container_of(bcontainer, VFIOContainer,
bcontainer);
VFIOSpaprContainer *scontainer = container_of(container, VFIOSpaprContainer,
container);
VFIOHostDMAWindow *hostwin;
hwaddr pgsize = 0;
int ret;
/*
* VFIO_SPAPR_TCE_IOMMU supports a single host window between
* [dma32_window_start, dma32_window_size), we need to ensure
* the section fall in this range.
*/
if (container->iommu_type == VFIO_SPAPR_TCE_IOMMU) {
hwaddr iova, end;
iova = section->offset_within_address_space;
end = iova + int128_get64(section->size) - 1;
if (!vfio_find_hostwin(scontainer, iova, end)) {
error_setg(errp, "Container %p can't map guest IOVA region"
" 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx, container,
iova, end);
return false;
}
return true;
}
if (container->iommu_type != VFIO_SPAPR_TCE_v2_IOMMU) {
return true;
}
/* For now intersections are not allowed, we may relax this later */
QLIST_FOREACH(hostwin, &scontainer->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(errp,
"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);
return false;
}
}
ret = vfio_spapr_create_window(container, section, &pgsize);
if (ret) {
error_setg_errno(errp, -ret, "Failed to create SPAPR window");
return false;
}
vfio_host_win_add(scontainer, 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_setg_errno(errp, errno,
"vfio: failed GROUP_SET_SPAPR_TCE for "
"KVM VFIO device %d and group fd %d",
param.tablefd, param.groupfd);
return false;
}
trace_vfio_spapr_group_attach(param.groupfd, param.tablefd);
}
}
}
#endif
return true;
}
static void
vfio_spapr_container_del_section_window(VFIOContainerBase *bcontainer,
MemoryRegionSection *section)
{
VFIOContainer *container = container_of(bcontainer, VFIOContainer,
bcontainer);
VFIOSpaprContainer *scontainer = container_of(container, VFIOSpaprContainer,
container);
if (container->iommu_type != VFIO_SPAPR_TCE_v2_IOMMU) {
return;
}
vfio_spapr_remove_window(container,
section->offset_within_address_space);
if (vfio_host_win_del(scontainer,
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_spapr_container_release(VFIOContainerBase *bcontainer)
{
VFIOContainer *container = container_of(bcontainer, VFIOContainer,
bcontainer);
VFIOSpaprContainer *scontainer = container_of(container, VFIOSpaprContainer,
container);
VFIOHostDMAWindow *hostwin, *next;
if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
memory_listener_unregister(&scontainer->prereg_listener);
}
QLIST_FOREACH_SAFE(hostwin, &scontainer->hostwin_list, hostwin_next,
next) {
QLIST_REMOVE(hostwin, hostwin_next);
g_free(hostwin);
}
}
static bool vfio_spapr_container_setup(VFIOContainerBase *bcontainer,
Error **errp)
{
VFIOContainer *container = container_of(bcontainer, VFIOContainer,
bcontainer);
VFIOSpaprContainer *scontainer = container_of(container, VFIOSpaprContainer,
container);
struct vfio_iommu_spapr_tce_info info;
bool v2 = container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU;
int ret, fd = container->fd;
QLIST_INIT(&scontainer->hostwin_list);
/*
* 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");
return false;
}
} else {
scontainer->prereg_listener = vfio_prereg_listener;
memory_listener_register(&scontainer->prereg_listener,
&address_space_memory);
if (bcontainer->error) {
error_propagate_prepend(errp, bcontainer->error,
"RAM memory listener initialization failed: ");
goto listener_unregister_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");
goto listener_unregister_exit;
}
if (v2) {
bcontainer->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 listener_unregister_exit;
}
} else {
/* The default table uses 4K pages */
bcontainer->pgsizes = 0x1000;
vfio_host_win_add(scontainer, info.dma32_window_start,
info.dma32_window_start +
info.dma32_window_size - 1,
0x1000);
}
return true;
listener_unregister_exit:
if (v2) {
memory_listener_unregister(&scontainer->prereg_listener);
}
return false;
}
static void vfio_iommu_spapr_class_init(ObjectClass *klass, void *data)
{
VFIOIOMMUClass *vioc = VFIO_IOMMU_CLASS(klass);
vioc->add_window = vfio_spapr_container_add_section_window;
vioc->del_window = vfio_spapr_container_del_section_window;
vioc->release = vfio_spapr_container_release;
vioc->setup = vfio_spapr_container_setup;
};
static const TypeInfo types[] = {
{
.name = TYPE_VFIO_IOMMU_SPAPR,
.parent = TYPE_VFIO_IOMMU_LEGACY,
.class_init = vfio_iommu_spapr_class_init,
},
};
DEFINE_TYPES(types)