qemu/hw/i386/xen/xen-hvm.c
Marek Marczykowski-Górecki b2bbadc63c hw/xen: detect when running inside stubdomain
Introduce global xen_is_stubdomain variable when qemu is running inside
a stubdomain instead of dom0. This will be relevant for subsequent
patches, as few things like accessing PCI config space need to be done
differently.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Message-Id: <e66aa97dca5120f22e015c19710b2ff04f525720.1711506237.git-series.marmarek@invisiblethingslab.com>
Signed-off-by: Anthony PERARD <anthony@xenproject.org>
2024-07-01 14:57:18 +02:00

756 lines
22 KiB
C

/*
* Copyright (C) 2010 Citrix Ltd.
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#include "qemu/units.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-migration.h"
#include "trace.h"
#include "hw/i386/pc.h"
#include "hw/irq.h"
#include "hw/i386/apic-msidef.h"
#include "hw/xen/xen-x86.h"
#include "qemu/range.h"
#include "hw/xen/xen-hvm-common.h"
#include "hw/xen/arch_hvm.h"
#include <xen/hvm/e820.h>
#include "exec/target_page.h"
static MemoryRegion ram_640k, ram_lo, ram_hi;
static MemoryRegion *framebuffer;
static bool xen_in_migration;
/* Compatibility with older version */
/*
* This allows QEMU to build on a system that has Xen 4.5 or earlier installed.
* This is here (not in hw/xen/xen_native.h) because xen/hvm/ioreq.h needs to
* be included before this block and hw/xen/xen_native.h needs to be included
* before xen/hvm/ioreq.h
*/
#ifndef IOREQ_TYPE_VMWARE_PORT
#define IOREQ_TYPE_VMWARE_PORT 3
struct vmware_regs {
uint32_t esi;
uint32_t edi;
uint32_t ebx;
uint32_t ecx;
uint32_t edx;
};
typedef struct vmware_regs vmware_regs_t;
struct shared_vmport_iopage {
struct vmware_regs vcpu_vmport_regs[1];
};
typedef struct shared_vmport_iopage shared_vmport_iopage_t;
#endif
static shared_vmport_iopage_t *shared_vmport_page;
static QLIST_HEAD(, XenPhysmap) xen_physmap;
static const XenPhysmap *log_for_dirtybit;
/* Buffer used by xen_sync_dirty_bitmap */
static unsigned long *dirty_bitmap;
static Notifier suspend;
static Notifier wakeup;
/* Xen specific function for piix pci */
int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
{
return irq_num + (PCI_SLOT(pci_dev->devfn) << 2);
}
void xen_intx_set_irq(void *opaque, int irq_num, int level)
{
xen_set_pci_intx_level(xen_domid, 0, 0, irq_num >> 2,
irq_num & 3, level);
}
int xen_set_pci_link_route(uint8_t link, uint8_t irq)
{
return xendevicemodel_set_pci_link_route(xen_dmod, xen_domid, link, irq);
}
int xen_is_pirq_msi(uint32_t msi_data)
{
/* If vector is 0, the msi is remapped into a pirq, passed as
* dest_id.
*/
return ((msi_data & MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT) == 0;
}
void xen_hvm_inject_msi(uint64_t addr, uint32_t data)
{
xen_inject_msi(xen_domid, addr, data);
}
static void xen_suspend_notifier(Notifier *notifier, void *data)
{
xc_set_hvm_param(xen_xc, xen_domid, HVM_PARAM_ACPI_S_STATE, 3);
}
/* Xen Interrupt Controller */
static void xen_set_irq(void *opaque, int irq, int level)
{
xen_set_isa_irq_level(xen_domid, irq, level);
}
qemu_irq *xen_interrupt_controller_init(void)
{
return qemu_allocate_irqs(xen_set_irq, NULL, 16);
}
/* Memory Ops */
static void xen_ram_init(PCMachineState *pcms,
ram_addr_t ram_size, MemoryRegion **ram_memory_p)
{
X86MachineState *x86ms = X86_MACHINE(pcms);
MemoryRegion *sysmem = get_system_memory();
ram_addr_t block_len;
uint64_t user_lowmem =
object_property_get_uint(qdev_get_machine(),
PC_MACHINE_MAX_RAM_BELOW_4G,
&error_abort);
/* Handle the machine opt max-ram-below-4g. It is basically doing
* min(xen limit, user limit).
*/
if (!user_lowmem) {
user_lowmem = HVM_BELOW_4G_RAM_END; /* default */
}
if (HVM_BELOW_4G_RAM_END <= user_lowmem) {
user_lowmem = HVM_BELOW_4G_RAM_END;
}
if (ram_size >= user_lowmem) {
x86ms->above_4g_mem_size = ram_size - user_lowmem;
x86ms->below_4g_mem_size = user_lowmem;
} else {
x86ms->above_4g_mem_size = 0;
x86ms->below_4g_mem_size = ram_size;
}
if (!x86ms->above_4g_mem_size) {
block_len = ram_size;
} else {
/*
* Xen does not allocate the memory continuously, it keeps a
* hole of the size computed above or passed in.
*/
block_len = (4 * GiB) + x86ms->above_4g_mem_size;
}
memory_region_init_ram(&xen_memory, NULL, "xen.ram", block_len,
&error_fatal);
*ram_memory_p = &xen_memory;
memory_region_init_alias(&ram_640k, NULL, "xen.ram.640k",
&xen_memory, 0, 0xa0000);
memory_region_add_subregion(sysmem, 0, &ram_640k);
/* Skip of the VGA IO memory space, it will be registered later by the VGA
* emulated device.
*
* The area between 0xc0000 and 0x100000 will be used by SeaBIOS to load
* the Options ROM, so it is registered here as RAM.
*/
memory_region_init_alias(&ram_lo, NULL, "xen.ram.lo",
&xen_memory, 0xc0000,
x86ms->below_4g_mem_size - 0xc0000);
memory_region_add_subregion(sysmem, 0xc0000, &ram_lo);
if (x86ms->above_4g_mem_size > 0) {
memory_region_init_alias(&ram_hi, NULL, "xen.ram.hi",
&xen_memory, 0x100000000ULL,
x86ms->above_4g_mem_size);
memory_region_add_subregion(sysmem, 0x100000000ULL, &ram_hi);
}
}
static XenPhysmap *get_physmapping(hwaddr start_addr, ram_addr_t size,
int page_mask)
{
XenPhysmap *physmap = NULL;
start_addr &= page_mask;
QLIST_FOREACH(physmap, &xen_physmap, list) {
if (range_covers_byte(physmap->start_addr, physmap->size, start_addr)) {
return physmap;
}
}
return NULL;
}
static hwaddr xen_phys_offset_to_gaddr(hwaddr phys_offset, ram_addr_t size,
int page_mask)
{
hwaddr addr = phys_offset & page_mask;
XenPhysmap *physmap = NULL;
QLIST_FOREACH(physmap, &xen_physmap, list) {
if (range_covers_byte(physmap->phys_offset, physmap->size, addr)) {
return physmap->start_addr + (phys_offset - physmap->phys_offset);
}
}
return phys_offset;
}
#ifdef XEN_COMPAT_PHYSMAP
static int xen_save_physmap(XenIOState *state, XenPhysmap *physmap)
{
char path[80], value[17];
snprintf(path, sizeof(path),
"/local/domain/0/device-model/%d/physmap/%"PRIx64"/start_addr",
xen_domid, (uint64_t)physmap->phys_offset);
snprintf(value, sizeof(value), "%"PRIx64, (uint64_t)physmap->start_addr);
if (!xs_write(state->xenstore, 0, path, value, strlen(value))) {
return -1;
}
snprintf(path, sizeof(path),
"/local/domain/0/device-model/%d/physmap/%"PRIx64"/size",
xen_domid, (uint64_t)physmap->phys_offset);
snprintf(value, sizeof(value), "%"PRIx64, (uint64_t)physmap->size);
if (!xs_write(state->xenstore, 0, path, value, strlen(value))) {
return -1;
}
if (physmap->name) {
snprintf(path, sizeof(path),
"/local/domain/0/device-model/%d/physmap/%"PRIx64"/name",
xen_domid, (uint64_t)physmap->phys_offset);
if (!xs_write(state->xenstore, 0, path,
physmap->name, strlen(physmap->name))) {
return -1;
}
}
return 0;
}
#else
static int xen_save_physmap(XenIOState *state, XenPhysmap *physmap)
{
return 0;
}
#endif
static int xen_add_to_physmap(XenIOState *state,
hwaddr start_addr,
ram_addr_t size,
MemoryRegion *mr,
hwaddr offset_within_region)
{
unsigned target_page_bits = qemu_target_page_bits();
int page_size = qemu_target_page_size();
int page_mask = -page_size;
unsigned long nr_pages;
int rc = 0;
XenPhysmap *physmap = NULL;
hwaddr pfn, start_gpfn;
hwaddr phys_offset = memory_region_get_ram_addr(mr);
const char *mr_name;
if (get_physmapping(start_addr, size, page_mask)) {
return 0;
}
if (size <= 0) {
return -1;
}
/* Xen can only handle a single dirty log region for now and we want
* the linear framebuffer to be that region.
* Avoid tracking any regions that is not videoram and avoid tracking
* the legacy vga region. */
if (mr == framebuffer && start_addr > 0xbffff) {
goto go_physmap;
}
return -1;
go_physmap:
DPRINTF("mapping vram to %"HWADDR_PRIx" - %"HWADDR_PRIx"\n",
start_addr, start_addr + size);
mr_name = memory_region_name(mr);
physmap = g_new(XenPhysmap, 1);
physmap->start_addr = start_addr;
physmap->size = size;
physmap->name = mr_name;
physmap->phys_offset = phys_offset;
QLIST_INSERT_HEAD(&xen_physmap, physmap, list);
if (runstate_check(RUN_STATE_INMIGRATE)) {
/* Now when we have a physmap entry we can replace a dummy mapping with
* a real one of guest foreign memory. */
uint8_t *p = xen_replace_cache_entry(phys_offset, start_addr, size);
assert(p && p == memory_region_get_ram_ptr(mr));
return 0;
}
pfn = phys_offset >> target_page_bits;
start_gpfn = start_addr >> target_page_bits;
nr_pages = size >> target_page_bits;
rc = xendevicemodel_relocate_memory(xen_dmod, xen_domid, nr_pages, pfn,
start_gpfn);
if (rc) {
int saved_errno = errno;
error_report("relocate_memory %lu pages from GFN %"HWADDR_PRIx
" to GFN %"HWADDR_PRIx" failed: %s",
nr_pages, pfn, start_gpfn, strerror(saved_errno));
errno = saved_errno;
return -1;
}
rc = xendevicemodel_pin_memory_cacheattr(xen_dmod, xen_domid,
start_addr >> target_page_bits,
(start_addr + size - 1) >> target_page_bits,
XEN_DOMCTL_MEM_CACHEATTR_WB);
if (rc) {
error_report("pin_memory_cacheattr failed: %s", strerror(errno));
}
return xen_save_physmap(state, physmap);
}
static int xen_remove_from_physmap(XenIOState *state,
hwaddr start_addr,
ram_addr_t size)
{
unsigned target_page_bits = qemu_target_page_bits();
int page_size = qemu_target_page_size();
int page_mask = -page_size;
int rc = 0;
XenPhysmap *physmap = NULL;
hwaddr phys_offset = 0;
physmap = get_physmapping(start_addr, size, page_mask);
if (physmap == NULL) {
return -1;
}
phys_offset = physmap->phys_offset;
size = physmap->size;
DPRINTF("unmapping vram to %"HWADDR_PRIx" - %"HWADDR_PRIx", at "
"%"HWADDR_PRIx"\n", start_addr, start_addr + size, phys_offset);
size >>= target_page_bits;
start_addr >>= target_page_bits;
phys_offset >>= target_page_bits;
rc = xendevicemodel_relocate_memory(xen_dmod, xen_domid, size, start_addr,
phys_offset);
if (rc) {
int saved_errno = errno;
error_report("relocate_memory "RAM_ADDR_FMT" pages"
" from GFN %"HWADDR_PRIx
" to GFN %"HWADDR_PRIx" failed: %s",
size, start_addr, phys_offset, strerror(saved_errno));
errno = saved_errno;
return -1;
}
QLIST_REMOVE(physmap, list);
if (log_for_dirtybit == physmap) {
log_for_dirtybit = NULL;
g_free(dirty_bitmap);
dirty_bitmap = NULL;
}
g_free(physmap);
return 0;
}
static void xen_sync_dirty_bitmap(XenIOState *state,
hwaddr start_addr,
ram_addr_t size)
{
unsigned target_page_bits = qemu_target_page_bits();
int page_size = qemu_target_page_size();
int page_mask = -page_size;
hwaddr npages = size >> target_page_bits;
const int width = sizeof(unsigned long) * 8;
size_t bitmap_size = DIV_ROUND_UP(npages, width);
int rc, i, j;
const XenPhysmap *physmap = NULL;
physmap = get_physmapping(start_addr, size, page_mask);
if (physmap == NULL) {
/* not handled */
return;
}
if (log_for_dirtybit == NULL) {
log_for_dirtybit = physmap;
dirty_bitmap = g_new(unsigned long, bitmap_size);
} else if (log_for_dirtybit != physmap) {
/* Only one range for dirty bitmap can be tracked. */
return;
}
rc = xen_track_dirty_vram(xen_domid, start_addr >> target_page_bits,
npages, dirty_bitmap);
if (rc < 0) {
#ifndef ENODATA
#define ENODATA ENOENT
#endif
if (errno == ENODATA) {
memory_region_set_dirty(framebuffer, 0, size);
DPRINTF("xen: track_dirty_vram failed (0x" HWADDR_FMT_plx
", 0x" HWADDR_FMT_plx "): %s\n",
start_addr, start_addr + size, strerror(errno));
}
return;
}
for (i = 0; i < bitmap_size; i++) {
unsigned long map = dirty_bitmap[i];
while (map != 0) {
j = ctzl(map);
map &= ~(1ul << j);
memory_region_set_dirty(framebuffer,
(i * width + j) * page_size, page_size);
};
}
}
static void xen_log_start(MemoryListener *listener,
MemoryRegionSection *section,
int old, int new)
{
XenIOState *state = container_of(listener, XenIOState, memory_listener);
if (new & ~old & (1 << DIRTY_MEMORY_VGA)) {
xen_sync_dirty_bitmap(state, section->offset_within_address_space,
int128_get64(section->size));
}
}
static void xen_log_stop(MemoryListener *listener, MemoryRegionSection *section,
int old, int new)
{
if (old & ~new & (1 << DIRTY_MEMORY_VGA)) {
log_for_dirtybit = NULL;
g_free(dirty_bitmap);
dirty_bitmap = NULL;
/* Disable dirty bit tracking */
xen_track_dirty_vram(xen_domid, 0, 0, NULL);
}
}
static void xen_log_sync(MemoryListener *listener, MemoryRegionSection *section)
{
XenIOState *state = container_of(listener, XenIOState, memory_listener);
xen_sync_dirty_bitmap(state, section->offset_within_address_space,
int128_get64(section->size));
}
static bool xen_log_global_start(MemoryListener *listener, Error **errp)
{
if (xen_enabled()) {
xen_in_migration = true;
}
return true;
}
static void xen_log_global_stop(MemoryListener *listener)
{
xen_in_migration = false;
}
static const MemoryListener xen_memory_listener = {
.name = "xen-memory",
.region_add = xen_region_add,
.region_del = xen_region_del,
.log_start = xen_log_start,
.log_stop = xen_log_stop,
.log_sync = xen_log_sync,
.log_global_start = xen_log_global_start,
.log_global_stop = xen_log_global_stop,
.priority = MEMORY_LISTENER_PRIORITY_ACCEL,
};
static void regs_to_cpu(vmware_regs_t *vmport_regs, ioreq_t *req)
{
X86CPU *cpu;
CPUX86State *env;
cpu = X86_CPU(current_cpu);
env = &cpu->env;
env->regs[R_EAX] = req->data;
env->regs[R_EBX] = vmport_regs->ebx;
env->regs[R_ECX] = vmport_regs->ecx;
env->regs[R_EDX] = vmport_regs->edx;
env->regs[R_ESI] = vmport_regs->esi;
env->regs[R_EDI] = vmport_regs->edi;
}
static void regs_from_cpu(vmware_regs_t *vmport_regs)
{
X86CPU *cpu = X86_CPU(current_cpu);
CPUX86State *env = &cpu->env;
vmport_regs->ebx = env->regs[R_EBX];
vmport_regs->ecx = env->regs[R_ECX];
vmport_regs->edx = env->regs[R_EDX];
vmport_regs->esi = env->regs[R_ESI];
vmport_regs->edi = env->regs[R_EDI];
}
static void handle_vmport_ioreq(XenIOState *state, ioreq_t *req)
{
vmware_regs_t *vmport_regs;
assert(shared_vmport_page);
vmport_regs =
&shared_vmport_page->vcpu_vmport_regs[state->send_vcpu];
QEMU_BUILD_BUG_ON(sizeof(*req) < sizeof(*vmport_regs));
current_cpu = state->cpu_by_vcpu_id[state->send_vcpu];
regs_to_cpu(vmport_regs, req);
cpu_ioreq_pio(req);
regs_from_cpu(vmport_regs);
current_cpu = NULL;
}
#ifdef XEN_COMPAT_PHYSMAP
static void xen_read_physmap(XenIOState *state)
{
XenPhysmap *physmap = NULL;
unsigned int len, num, i;
char path[80], *value = NULL;
char **entries = NULL;
snprintf(path, sizeof(path),
"/local/domain/0/device-model/%d/physmap", xen_domid);
entries = xs_directory(state->xenstore, 0, path, &num);
if (entries == NULL)
return;
for (i = 0; i < num; i++) {
physmap = g_new(XenPhysmap, 1);
physmap->phys_offset = strtoull(entries[i], NULL, 16);
snprintf(path, sizeof(path),
"/local/domain/0/device-model/%d/physmap/%s/start_addr",
xen_domid, entries[i]);
value = xs_read(state->xenstore, 0, path, &len);
if (value == NULL) {
g_free(physmap);
continue;
}
physmap->start_addr = strtoull(value, NULL, 16);
free(value);
snprintf(path, sizeof(path),
"/local/domain/0/device-model/%d/physmap/%s/size",
xen_domid, entries[i]);
value = xs_read(state->xenstore, 0, path, &len);
if (value == NULL) {
g_free(physmap);
continue;
}
physmap->size = strtoull(value, NULL, 16);
free(value);
snprintf(path, sizeof(path),
"/local/domain/0/device-model/%d/physmap/%s/name",
xen_domid, entries[i]);
physmap->name = xs_read(state->xenstore, 0, path, &len);
QLIST_INSERT_HEAD(&xen_physmap, physmap, list);
}
free(entries);
}
#else
static void xen_read_physmap(XenIOState *state)
{
}
#endif
static void xen_wakeup_notifier(Notifier *notifier, void *data)
{
xc_set_hvm_param(xen_xc, xen_domid, HVM_PARAM_ACPI_S_STATE, 0);
}
static bool xen_check_stubdomain(struct xs_handle *xsh)
{
char *dm_path = g_strdup_printf(
"/local/domain/%d/image/device-model-domid", xen_domid);
char *val;
int32_t dm_domid;
bool is_stubdom = false;
val = xs_read(xsh, 0, dm_path, NULL);
if (val) {
if (sscanf(val, "%d", &dm_domid) == 1) {
is_stubdom = dm_domid != 0;
}
free(val);
}
g_free(dm_path);
return is_stubdom;
}
void xen_hvm_init_pc(PCMachineState *pcms, MemoryRegion **ram_memory)
{
MachineState *ms = MACHINE(pcms);
unsigned int max_cpus = ms->smp.max_cpus;
int rc;
xen_pfn_t ioreq_pfn;
XenIOState *state;
state = g_new0(XenIOState, 1);
xen_register_ioreq(state, max_cpus, &xen_memory_listener);
xen_is_stubdomain = xen_check_stubdomain(state->xenstore);
QLIST_INIT(&xen_physmap);
xen_read_physmap(state);
suspend.notify = xen_suspend_notifier;
qemu_register_suspend_notifier(&suspend);
wakeup.notify = xen_wakeup_notifier;
qemu_register_wakeup_notifier(&wakeup);
rc = xen_get_vmport_regs_pfn(xen_xc, xen_domid, &ioreq_pfn);
if (!rc) {
DPRINTF("shared vmport page at pfn %lx\n", ioreq_pfn);
shared_vmport_page =
xenforeignmemory_map(xen_fmem, xen_domid, PROT_READ|PROT_WRITE,
1, &ioreq_pfn, NULL);
if (shared_vmport_page == NULL) {
error_report("map shared vmport IO page returned error %d handle=%p",
errno, xen_xc);
goto err;
}
} else if (rc != -ENOSYS) {
error_report("get vmport regs pfn returned error %d, rc=%d",
errno, rc);
goto err;
}
xen_ram_init(pcms, ms->ram_size, ram_memory);
/* Disable ACPI build because Xen handles it */
pcms->acpi_build_enabled = false;
return;
err:
error_report("xen hardware virtual machine initialisation failed");
exit(1);
}
void xen_register_framebuffer(MemoryRegion *mr)
{
framebuffer = mr;
}
void xen_hvm_modified_memory(ram_addr_t start, ram_addr_t length)
{
unsigned target_page_bits = qemu_target_page_bits();
int page_size = qemu_target_page_size();
int page_mask = -page_size;
if (unlikely(xen_in_migration)) {
int rc;
ram_addr_t start_pfn, nb_pages;
start = xen_phys_offset_to_gaddr(start, length, page_mask);
if (length == 0) {
length = page_size;
}
start_pfn = start >> target_page_bits;
nb_pages = ((start + length + page_size - 1) >> target_page_bits)
- start_pfn;
rc = xen_modified_memory(xen_domid, start_pfn, nb_pages);
if (rc) {
fprintf(stderr,
"%s failed for "RAM_ADDR_FMT" ("RAM_ADDR_FMT"): %i, %s\n",
__func__, start, nb_pages, errno, strerror(errno));
}
}
}
void qmp_xen_set_global_dirty_log(bool enable, Error **errp)
{
if (enable) {
memory_global_dirty_log_start(GLOBAL_DIRTY_MIGRATION, errp);
} else {
memory_global_dirty_log_stop(GLOBAL_DIRTY_MIGRATION);
}
}
void arch_xen_set_memory(XenIOState *state, MemoryRegionSection *section,
bool add)
{
unsigned target_page_bits = qemu_target_page_bits();
int page_size = qemu_target_page_size();
int page_mask = -page_size;
hwaddr start_addr = section->offset_within_address_space;
ram_addr_t size = int128_get64(section->size);
bool log_dirty = memory_region_is_logging(section->mr, DIRTY_MEMORY_VGA);
hvmmem_type_t mem_type;
if (!memory_region_is_ram(section->mr)) {
return;
}
if (log_dirty != add) {
return;
}
trace_xen_client_set_memory(start_addr, size, log_dirty);
start_addr &= page_mask;
size = ROUND_UP(size, page_size);
if (add) {
if (!memory_region_is_rom(section->mr)) {
xen_add_to_physmap(state, start_addr, size,
section->mr, section->offset_within_region);
} else {
mem_type = HVMMEM_ram_ro;
if (xen_set_mem_type(xen_domid, mem_type,
start_addr >> target_page_bits,
size >> target_page_bits)) {
DPRINTF("xen_set_mem_type error, addr: "HWADDR_FMT_plx"\n",
start_addr);
}
}
} else {
if (xen_remove_from_physmap(state, start_addr, size) < 0) {
DPRINTF("physmapping does not exist at "HWADDR_FMT_plx"\n", start_addr);
}
}
}
void arch_handle_ioreq(XenIOState *state, ioreq_t *req)
{
switch (req->type) {
case IOREQ_TYPE_VMWARE_PORT:
handle_vmport_ioreq(state, req);
break;
default:
hw_error("Invalid ioreq type 0x%x\n", req->type);
}
return;
}