255 lines
8.9 KiB
C
255 lines
8.9 KiB
C
/*
|
|
* 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 "cpu.h"
|
|
#include <sys/ioctl.h>
|
|
#include <linux/vfio.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"
|
|
|
|
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)
|
|
{
|
|
VFIOContainer *container = container_of(listener, VFIOContainer,
|
|
prereg_listener);
|
|
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, ®);
|
|
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 (!container->initialized) {
|
|
if (!container->error) {
|
|
error_setg_errno(&container->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)
|
|
{
|
|
VFIOContainer *container = container_of(listener, VFIOContainer,
|
|
prereg_listener);
|
|
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, ®);
|
|
trace_vfio_prereg_unregister(reg.vaddr, reg.size, ret ? -errno : 0);
|
|
}
|
|
|
|
const MemoryListener vfio_prereg_listener = {
|
|
.region_add = vfio_prereg_listener_region_add,
|
|
.region_del = vfio_prereg_listener_region_del,
|
|
};
|
|
|
|
int vfio_spapr_create_window(VFIOContainer *container,
|
|
MemoryRegionSection *section,
|
|
hwaddr *pgsize)
|
|
{
|
|
int ret = 0;
|
|
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 = container->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),
|
|
container->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;
|
|
}
|
|
|
|
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;
|
|
}
|