@@ -858,6 +858,16 @@ tb_page_addr_t get_page_addr_code(CPUArchState *env, target_ulong addr)
pd = iotlbentry->addr & ~TARGET_PAGE_MASK;
mr = iotlb_to_region(cpu, pd, iotlbentry->attrs);
if (memory_region_is_unassigned(mr)) {
+ qemu_mutex_lock_iothread();
+ if (memory_region_request_mmio_ptr(mr, addr)) {
+ qemu_mutex_unlock_iothread();
+ /* A MemoryRegion is potentially added so re-run the
+ * get_page_addr_code.
+ */
+ return get_page_addr_code(env, addr);
+ }
+ qemu_mutex_unlock_iothread();
+
cpu_unassigned_access(cpu, addr, false, true, 0, 4);
/* The CPU's unassigned access hook might have longjumped out
* with an exception. If it didn't (or there was no hook) then
@@ -137,6 +137,15 @@ struct MemoryRegionOps {
uint64_t data,
unsigned size,
MemTxAttrs attrs);
+ /* Instruction execution pre-callback:
+ * @addr is the address of the access relative to the @mr.
+ * @size is the size of the area returned by the callback.
+ * @offset is the location of the pointer inside @mr.
+ *
+ * Returns a pointer to a location which contains guest code.
+ */
+ void *(*request_ptr)(void *opaque, hwaddr addr, unsigned *size,
+ unsigned *offset);
enum device_endian endianness;
/* Guest-visible constraints: */
@@ -1354,6 +1363,32 @@ void memory_global_dirty_log_stop(void);
void mtree_info(fprintf_function mon_printf, void *f, bool flatview);
/**
+ * memory_region_request_mmio_ptr: request a pointer to an mmio
+ * MemoryRegion. If it is possible map a RAM MemoryRegion with this pointer.
+ * When the device wants to invalidate the pointer it will call
+ * memory_region_invalidate_mmio_ptr.
+ *
+ * @mr: #MemoryRegion to check
+ * @addr: address within that region
+ *
+ * Returns true on success, false otherwise.
+ */
+bool memory_region_request_mmio_ptr(MemoryRegion *mr, hwaddr addr);
+
+/**
+ * memory_region_invalidate_mmio_ptr: invalidate the pointer to an mmio
+ * previously requested.
+ * In the end that means that if something wants to execute from this area it
+ * will need to request the pointer again.
+ *
+ * @mr: #MemoryRegion associated to the pointer.
+ * @addr: address within that region
+ * @size: size of that area.
+ */
+void memory_region_invalidate_mmio_ptr(MemoryRegion *mr, hwaddr offset,
+ unsigned size);
+
+/**
* memory_region_dispatch_read: perform a read directly to the specified
* MemoryRegion.
*
@@ -30,6 +30,8 @@
#include "exec/ram_addr.h"
#include "sysemu/kvm.h"
#include "sysemu/sysemu.h"
+#include "hw/misc/mmio_interface.h"
+#include "hw/qdev-properties.h"
//#define DEBUG_UNASSIGNED
@@ -2424,6 +2426,115 @@ void memory_listener_unregister(MemoryListener *listener)
listener->address_space = NULL;
}
+bool memory_region_request_mmio_ptr(MemoryRegion *mr, hwaddr addr)
+{
+ void *host;
+ unsigned size = 0;
+ unsigned offset = 0;
+ Object *new_interface;
+
+ if (!mr || !mr->ops->request_ptr) {
+ return false;
+ }
+
+ /*
+ * Avoid an update if the request_ptr call
+ * memory_region_invalidate_mmio_ptr which seems to be likely when we use
+ * a cache.
+ */
+ memory_region_transaction_begin();
+
+ host = mr->ops->request_ptr(mr->opaque, addr - mr->addr, &size, &offset);
+
+ if (!host || !size) {
+ memory_region_transaction_commit();
+ return false;
+ }
+
+ new_interface = object_new("mmio_interface");
+ qdev_prop_set_uint64(DEVICE(new_interface), "start", offset);
+ qdev_prop_set_uint64(DEVICE(new_interface), "end", offset + size - 1);
+ qdev_prop_set_bit(DEVICE(new_interface), "ro", true);
+ qdev_prop_set_ptr(DEVICE(new_interface), "host_ptr", host);
+ qdev_prop_set_ptr(DEVICE(new_interface), "subregion", mr);
+ object_property_set_bool(OBJECT(new_interface), true, "realized", NULL);
+
+ memory_region_transaction_commit();
+ return true;
+}
+
+typedef struct MMIOPtrInvalidate {
+ MemoryRegion *mr;
+ hwaddr offset;
+ unsigned size;
+ int busy;
+ int allocated;
+} MMIOPtrInvalidate;
+
+#define MAX_MMIO_INVALIDATE 10
+static MMIOPtrInvalidate mmio_ptr_invalidate_list[MAX_MMIO_INVALIDATE];
+
+static void memory_region_do_invalidate_mmio_ptr(CPUState *cpu,
+ run_on_cpu_data data)
+{
+ MMIOPtrInvalidate *invalidate_data = (MMIOPtrInvalidate *)data.host_ptr;
+ MemoryRegion *mr = invalidate_data->mr;
+ hwaddr offset = invalidate_data->offset;
+ unsigned size = invalidate_data->size;
+ MemoryRegionSection section = memory_region_find(mr, offset, size);
+
+ qemu_mutex_lock_iothread();
+
+ /* Reset dirty so this doesn't happen later. */
+ cpu_physical_memory_test_and_clear_dirty(offset, size, 1);
+
+ if (section.mr != mr) {
+ /* memory_region_find add a ref on section.mr */
+ memory_region_unref(section.mr);
+ if (MMIO_INTERFACE(section.mr->owner)) {
+ /* We found the interface just drop it. */
+ object_property_set_bool(section.mr->owner, false, "realized",
+ NULL);
+ object_unref(section.mr->owner);
+ object_unparent(section.mr->owner);
+ }
+ }
+
+ qemu_mutex_unlock_iothread();
+
+ if (invalidate_data->allocated) {
+ g_free(invalidate_data);
+ } else {
+ invalidate_data->busy = 0;
+ }
+}
+
+void memory_region_invalidate_mmio_ptr(MemoryRegion *mr, hwaddr offset,
+ unsigned size)
+{
+ size_t i;
+ MMIOPtrInvalidate *invalidate_data = NULL;
+
+ for (i = 0; i < MAX_MMIO_INVALIDATE; i++) {
+ if (atomic_cmpxchg(&(mmio_ptr_invalidate_list[i].busy), 0, 1) == 0) {
+ invalidate_data = &mmio_ptr_invalidate_list[i];
+ break;
+ }
+ }
+
+ if (!invalidate_data) {
+ invalidate_data = g_malloc0(sizeof(MMIOPtrInvalidate));
+ invalidate_data->allocated = 1;
+ }
+
+ invalidate_data->mr = mr;
+ invalidate_data->offset = offset;
+ invalidate_data->size = size;
+
+ async_safe_run_on_cpu(first_cpu, memory_region_do_invalidate_mmio_ptr,
+ RUN_ON_CPU_HOST_PTR(invalidate_data));
+}
+
void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name)
{
memory_region_ref(root);