i386: hvf: implement vga dirty page tracking

This patch implements setting the tracking of dirty vga pages, using hvf's
interface to protect guest memory. It uses the MemoryListener callback
mechanism through .log_start/stop/sync

Signed-off-by: Sergio Andres Gomez Del Real <Sergio.G.DelReal@gmail.com>
Message-Id: <20170913090522.4022-13-Sergio.G.DelReal@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sergio Andres Gomez Del Real 2017-09-13 04:05:20 -05:00 committed by Paolo Bonzini
parent d6dcc5583e
commit babfa20ca4
2 changed files with 71 additions and 7 deletions

View File

@ -34,11 +34,16 @@ uint32_t hvf_get_supported_cpuid(uint32_t func, uint32_t idx,
#define hvf_get_supported_cpuid(func, idx, reg) 0
#endif
/* hvf_slot flags */
#define HVF_SLOT_LOG (1 << 0)
typedef struct hvf_slot {
uint64_t start;
uint64_t size;
uint8_t *mem;
int slot_id;
uint32_t flags;
MemoryRegion *region;
} hvf_slot;
typedef struct hvf_vcpu_caps {

View File

@ -193,6 +193,7 @@ void hvf_set_phys_mem(MemoryRegionSection *section, bool add)
mem->size = int128_get64(section->size);
mem->mem = memory_region_get_ram_ptr(area) + section->offset_within_region;
mem->start = section->offset_within_address_space;
mem->region = area;
if (do_hvf_set_memory(mem)) {
error_report("Error registering new memory slot\n");
@ -289,8 +290,7 @@ void hvf_cpu_synchronize_post_init(CPUState *cpu_state)
run_on_cpu(cpu_state, _hvf_cpu_synchronize_post_init, RUN_ON_CPU_NULL);
}
/* TODO: ept fault handlig */
static bool ept_emulation_fault(uint64_t ept_qual)
static bool ept_emulation_fault(hvf_slot *slot, addr_t gpa, uint64_t ept_qual)
{
int read, write;
@ -306,6 +306,14 @@ static bool ept_emulation_fault(uint64_t ept_qual)
return false;
}
if (write && slot) {
if (slot->flags & HVF_SLOT_LOG) {
memory_region_set_dirty(slot->region, gpa - slot->start, 1);
hv_vm_protect((hv_gpaddr_t)slot->start, (size_t)slot->size,
HV_MEMORY_READ | HV_MEMORY_WRITE);
}
}
/*
* The EPT violation must have been caused by accessing a
* guest-physical address that is a translation of a guest-linear
@ -316,7 +324,58 @@ static bool ept_emulation_fault(uint64_t ept_qual)
return false;
}
return true;
return !slot;
}
static void hvf_set_dirty_tracking(MemoryRegionSection *section, bool on)
{
hvf_slot *slot;
slot = hvf_find_overlap_slot(
section->offset_within_address_space,
section->offset_within_address_space + int128_get64(section->size));
/* protect region against writes; begin tracking it */
if (on) {
slot->flags |= HVF_SLOT_LOG;
hv_vm_protect((hv_gpaddr_t)slot->start, (size_t)slot->size,
HV_MEMORY_READ);
/* stop tracking region*/
} else {
slot->flags &= ~HVF_SLOT_LOG;
hv_vm_protect((hv_gpaddr_t)slot->start, (size_t)slot->size,
HV_MEMORY_READ | HV_MEMORY_WRITE);
}
}
static void hvf_log_start(MemoryListener *listener,
MemoryRegionSection *section, int old, int new)
{
if (old != 0) {
return;
}
hvf_set_dirty_tracking(section, 1);
}
static void hvf_log_stop(MemoryListener *listener,
MemoryRegionSection *section, int old, int new)
{
if (new != 0) {
return;
}
hvf_set_dirty_tracking(section, 0);
}
static void hvf_log_sync(MemoryListener *listener,
MemoryRegionSection *section)
{
/*
* sync of dirty pages is handled elsewhere; just make sure we keep
* tracking the region.
*/
hvf_set_dirty_tracking(section, 1);
}
static void hvf_region_add(MemoryListener *listener,
@ -335,6 +394,9 @@ static MemoryListener hvf_memory_listener = {
.priority = 10,
.region_add = hvf_region_add,
.region_del = hvf_region_del,
.log_start = hvf_log_start,
.log_stop = hvf_log_stop,
.log_sync = hvf_log_sync,
};
void hvf_reset_vcpu(CPUState *cpu) {
@ -607,7 +669,7 @@ int hvf_vcpu_exec(CPUState *cpu)
slot = hvf_find_overlap_slot(gpa, gpa);
/* mmio */
if (ept_emulation_fault(exit_qual) && !slot) {
if (ept_emulation_fault(slot, gpa, exit_qual)) {
struct x86_decode decode;
load_regs(cpu);
@ -618,9 +680,6 @@ int hvf_vcpu_exec(CPUState *cpu)
store_regs(cpu);
break;
}
#ifdef DIRTY_VGA_TRACKING
/* TODO: handle dirty page tracking */
#endif
break;
}
case EXIT_REASON_INOUT: