static bool memory_region_update_pending;
static bool global_dirty_log = false;
+/* flat_view_mutex is taken around reading as->current_map; the critical
+ * section is extremely short, so I'm using a single mutex for every AS.
+ * We could also RCU for the read-side.
+ *
+ * The BQL is taken around transaction commits, hence both locks are taken
+ * while writing to as->current_map (with the BQL taken outside).
+ */
+static QemuMutex flat_view_mutex;
+
static QTAILQ_HEAD(memory_listeners, MemoryListener) memory_listeners
= QTAILQ_HEAD_INITIALIZER(memory_listeners);
static QTAILQ_HEAD(, AddressSpace) address_spaces
= QTAILQ_HEAD_INITIALIZER(address_spaces);
+static void memory_init(void)
+{
+ qemu_mutex_init(&flat_view_mutex);
+}
+
typedef struct AddrRange AddrRange;
/*
* order.
*/
struct FlatView {
+ unsigned ref;
FlatRange *ranges;
unsigned nr;
unsigned nr_allocated;
static void flatview_init(FlatView *view)
{
+ view->ref = 1;
view->ranges = NULL;
view->nr = 0;
view->nr_allocated = 0;
g_free(view);
}
+static void flatview_ref(FlatView *view)
+{
+ atomic_inc(&view->ref);
+}
+
+static void flatview_unref(FlatView *view)
+{
+ if (atomic_fetch_dec(&view->ref) == 1) {
+ flatview_destroy(view);
+ }
+}
+
static bool can_merge(FlatRange *r1, FlatRange *r2)
{
return int128_eq(addrrange_end(r1->addr), r2->addr.start)
}
}
+static FlatView *address_space_get_flatview(AddressSpace *as)
+{
+ FlatView *view;
+
+ qemu_mutex_lock(&flat_view_mutex);
+ view = as->current_map;
+ flatview_ref(view);
+ qemu_mutex_unlock(&flat_view_mutex);
+ return view;
+}
+
static void address_space_update_ioeventfds(AddressSpace *as)
{
FlatView *view;
AddrRange tmp;
unsigned i;
- view = as->current_map;
+ view = address_space_get_flatview(as);
FOR_EACH_FLAT_RANGE(fr, view) {
for (i = 0; i < fr->mr->ioeventfd_nb; ++i) {
tmp = addrrange_shift(fr->mr->ioeventfds[i].addr,
g_free(as->ioeventfds);
as->ioeventfds = ioeventfds;
as->ioeventfd_nb = ioeventfd_nb;
+ flatview_unref(view);
}
static void address_space_update_topology_pass(AddressSpace *as,
static void address_space_update_topology(AddressSpace *as)
{
- FlatView *old_view = as->current_map;
+ FlatView *old_view = address_space_get_flatview(as);
FlatView *new_view = generate_memory_topology(as->root);
address_space_update_topology_pass(as, old_view, new_view, false);
address_space_update_topology_pass(as, old_view, new_view, true);
+ qemu_mutex_lock(&flat_view_mutex);
+ flatview_unref(as->current_map);
as->current_map = new_view;
- flatview_destroy(old_view);
+ qemu_mutex_unlock(&flat_view_mutex);
+
+ /* Note that all the old MemoryRegions are still alive up to this
+ * point. This relieves most MemoryListeners from the need to
+ * ref/unref the MemoryRegions they get---unless they use them
+ * outside the iothread mutex, in which case precise reference
+ * counting is necessary.
+ */
+ flatview_unref(old_view);
+
address_space_update_ioeventfds(as);
}
mr->owner = owner;
mr->iommu_ops = NULL;
mr->parent = NULL;
- mr->owner = NULL;
mr->size = int128_make64(size);
if (size == UINT64_MAX) {
mr->size = int128_2_64();
#ifdef DEBUG_UNASSIGNED
printf("Unassigned mem read " TARGET_FMT_plx "\n", addr);
#endif
- if (cpu_single_env != NULL) {
- cpu_unassigned_access(ENV_GET_CPU(cpu_single_env),
- addr, false, false, 0, size);
+ if (current_cpu != NULL) {
+ cpu_unassigned_access(current_cpu, addr, false, false, 0, size);
}
- return 0;
+ return -1ULL;
}
static void unassigned_mem_write(void *opaque, hwaddr addr,
#ifdef DEBUG_UNASSIGNED
printf("Unassigned mem write " TARGET_FMT_plx " = 0x%"PRIx64"\n", addr, val);
#endif
- if (cpu_single_env != NULL) {
- cpu_unassigned_access(ENV_GET_CPU(cpu_single_env),
- addr, true, false, 0, size);
+ if (current_cpu != NULL) {
+ cpu_unassigned_access(current_cpu, addr, true, false, 0, size);
}
}
FlatRange *fr;
QTAILQ_FOREACH(as, &address_spaces, address_spaces_link) {
- FlatView *view = as->current_map;
+ FlatView *view = address_space_get_flatview(as);
FOR_EACH_FLAT_RANGE(fr, view) {
if (fr->mr == mr) {
MEMORY_LISTENER_UPDATE_REGION(fr, as, Forward, log_sync);
}
}
+ flatview_unref(view);
}
}
AddrRange tmp;
MemoryRegionSection section;
- view = as->current_map;
+ view = address_space_get_flatview(as);
FOR_EACH_FLAT_RANGE(fr, view) {
if (fr->mr == mr) {
section = (MemoryRegionSection) {
}
}
}
+ flatview_unref(view);
}
static void memory_region_update_coalesced_range(MemoryRegion *mr)
as = memory_region_to_address_space(root);
range = addrrange_make(int128_make64(addr), int128_make64(size));
- view = as->current_map;
+ view = address_space_get_flatview(as);
fr = flatview_lookup(view, range);
if (!fr) {
return ret;
ret.readonly = fr->readonly;
memory_region_ref(ret.mr);
+ flatview_unref(view);
return ret;
}
FlatView *view;
FlatRange *fr;
- view = as->current_map;
+ view = address_space_get_flatview(as);
FOR_EACH_FLAT_RANGE(fr, view) {
MEMORY_LISTENER_UPDATE_REGION(fr, as, Forward, log_sync);
}
+ flatview_unref(view);
}
void memory_global_dirty_log_start(void)
}
}
- view = as->current_map;
+ view = address_space_get_flatview(as);
FOR_EACH_FLAT_RANGE(fr, view) {
MemoryRegionSection section = {
.mr = fr->mr,
listener->region_add(listener, §ion);
}
}
+ flatview_unref(view);
}
void memory_listener_register(MemoryListener *listener, AddressSpace *filter)
void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name)
{
+ if (QTAILQ_EMPTY(&address_spaces)) {
+ memory_init();
+ }
+
memory_region_transaction_begin();
as->root = root;
as->current_map = g_new(FlatView, 1);
memory_region_transaction_commit();
QTAILQ_REMOVE(&address_spaces, as, address_spaces_link);
address_space_destroy_dispatch(as);
- flatview_destroy(as->current_map);
+ flatview_unref(as->current_map);
g_free(as->name);
- g_free(as->current_map);
g_free(as->ioeventfds);
}
projects / qemu.git / blobdiff