]> git.proxmox.com Git - mirror_qemu.git/blobdiff - memory.c
qemu-img: Resolve relative backing paths in rebase
[mirror_qemu.git] / memory.c
index bf3728ae2f295ba0219fdfc0e38702e852bf0f6a..b2e23c31f4bfea7a5c04976c6fa5a64e3e5bdb8f 100644 (file)
--- a/memory.c
+++ b/memory.c
@@ -47,6 +47,8 @@ static QTAILQ_HEAD(memory_listeners, MemoryListener) memory_listeners
 static QTAILQ_HEAD(, AddressSpace) address_spaces
     = QTAILQ_HEAD_INITIALIZER(address_spaces);
 
+static GHashTable *flat_views;
+
 typedef struct AddrRange AddrRange;
 
 /*
@@ -208,8 +210,6 @@ static bool memory_region_ioeventfd_equal(MemoryRegionIoeventfd a,
         && !memory_region_ioeventfd_before(b, a);
 }
 
-typedef struct FlatRange FlatRange;
-
 /* Range of memory in the global map.  Addresses are absolute. */
 struct FlatRange {
     MemoryRegion *mr;
@@ -220,18 +220,6 @@ struct FlatRange {
     bool readonly;
 };
 
-/* Flattened global view of current active memory hierarchy.  Kept in sorted
- * order.
- */
-struct FlatView {
-    struct rcu_head rcu;
-    unsigned ref;
-    FlatRange *ranges;
-    unsigned nr;
-    unsigned nr_allocated;
-    struct AddressSpaceDispatch *dispatch;
-};
-
 typedef struct AddressSpaceOps AddressSpaceOps;
 
 #define FOR_EACH_FLAT_RANGE(var, view)          \
@@ -259,12 +247,15 @@ static bool flatrange_equal(FlatRange *a, FlatRange *b)
         && a->readonly == b->readonly;
 }
 
-static FlatView *flatview_new(void)
+static FlatView *flatview_new(MemoryRegion *mr_root)
 {
     FlatView *view;
 
     view = g_new0(FlatView, 1);
     view->ref = 1;
+    view->root = mr_root;
+    memory_region_ref(mr_root);
+    trace_flatview_new(view, mr_root);
 
     return view;
 }
@@ -290,6 +281,7 @@ static void flatview_destroy(FlatView *view)
 {
     int i;
 
+    trace_flatview_destroy(view, view->root);
     if (view->dispatch) {
         address_space_dispatch_free(view->dispatch);
     }
@@ -297,6 +289,7 @@ static void flatview_destroy(FlatView *view)
         memory_region_unref(view->ranges[i].mr);
     }
     g_free(view->ranges);
+    memory_region_unref(view->root);
     g_free(view);
 }
 
@@ -308,25 +301,12 @@ static bool flatview_ref(FlatView *view)
 static void flatview_unref(FlatView *view)
 {
     if (atomic_fetch_dec(&view->ref) == 1) {
+        trace_flatview_destroy_rcu(view, view->root);
+        assert(view->root);
         call_rcu(view, flatview_destroy, rcu);
     }
 }
 
-FlatView *address_space_to_flatview(AddressSpace *as)
-{
-    return atomic_rcu_read(&as->current_map);
-}
-
-AddressSpaceDispatch *flatview_to_dispatch(FlatView *fv)
-{
-    return fv->dispatch;
-}
-
-AddressSpaceDispatch *address_space_to_dispatch(AddressSpace *as)
-{
-    return flatview_to_dispatch(address_space_to_flatview(as));
-}
-
 static bool can_merge(FlatRange *r1, FlatRange *r2)
 {
     return int128_eq(addrrange_end(r1->addr), r2->addr.start)
@@ -723,12 +703,57 @@ static void render_memory_region(FlatView *view,
     }
 }
 
+static MemoryRegion *memory_region_get_flatview_root(MemoryRegion *mr)
+{
+    while (mr->enabled) {
+        if (mr->alias) {
+            if (!mr->alias_offset && int128_ge(mr->size, mr->alias->size)) {
+                /* The alias is included in its entirety.  Use it as
+                 * the "real" root, so that we can share more FlatViews.
+                 */
+                mr = mr->alias;
+                continue;
+            }
+        } else if (!mr->terminates) {
+            unsigned int found = 0;
+            MemoryRegion *child, *next = NULL;
+            QTAILQ_FOREACH(child, &mr->subregions, subregions_link) {
+                if (child->enabled) {
+                    if (++found > 1) {
+                        next = NULL;
+                        break;
+                    }
+                    if (!child->addr && int128_ge(mr->size, child->size)) {
+                        /* A child is included in its entirety.  If it's the only
+                         * enabled one, use it in the hope of finding an alias down the
+                         * way. This will also let us share FlatViews.
+                         */
+                        next = child;
+                    }
+                }
+            }
+            if (found == 0) {
+                return NULL;
+            }
+            if (next) {
+                mr = next;
+                continue;
+            }
+        }
+
+        return mr;
+    }
+
+    return NULL;
+}
+
 /* Render a memory topology into a list of disjoint absolute ranges. */
 static FlatView *generate_memory_topology(MemoryRegion *mr)
 {
+    int i;
     FlatView *view;
 
-    view = flatview_new();
+    view = flatview_new(mr);
 
     if (mr) {
         render_memory_region(view, mr, int128_zero(),
@@ -736,6 +761,15 @@ static FlatView *generate_memory_topology(MemoryRegion *mr)
     }
     flatview_simplify(view);
 
+    view->dispatch = address_space_dispatch_new(view);
+    for (i = 0; i < view->nr; i++) {
+        MemoryRegionSection mrs =
+            section_from_flat_range(&view->ranges[i], view);
+        flatview_add_to_dispatch(view, &mrs);
+    }
+    address_space_dispatch_compact(view->dispatch);
+    g_hash_table_replace(flat_views, mr, view);
+
     return view;
 }
 
@@ -904,28 +938,81 @@ static void address_space_update_topology_pass(AddressSpace *as,
     }
 }
 
-static void address_space_update_topology(AddressSpace *as)
+static void flatviews_init(void)
 {
-    FlatView *old_view = address_space_get_flatview(as);
-    FlatView *new_view = generate_memory_topology(as->root);
-    int i;
+    static FlatView *empty_view;
 
-    new_view->dispatch = mem_begin(as);
-    for (i = 0; i < new_view->nr; i++) {
-        MemoryRegionSection mrs =
-            section_from_flat_range(&new_view->ranges[i], new_view);
-        mem_add(new_view, &mrs);
+    if (flat_views) {
+        return;
+    }
+
+    flat_views = g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL,
+                                       (GDestroyNotify) flatview_unref);
+    if (!empty_view) {
+        empty_view = generate_memory_topology(NULL);
+        /* We keep it alive forever in the global variable.  */
+        flatview_ref(empty_view);
+    } else {
+        g_hash_table_replace(flat_views, NULL, empty_view);
+        flatview_ref(empty_view);
+    }
+}
+
+static void flatviews_reset(void)
+{
+    AddressSpace *as;
+
+    if (flat_views) {
+        g_hash_table_unref(flat_views);
+        flat_views = NULL;
+    }
+    flatviews_init();
+
+    /* Render unique FVs */
+    QTAILQ_FOREACH(as, &address_spaces, address_spaces_link) {
+        MemoryRegion *physmr = memory_region_get_flatview_root(as->root);
+
+        if (g_hash_table_lookup(flat_views, physmr)) {
+            continue;
+        }
+
+        generate_memory_topology(physmr);
+    }
+}
+
+static void address_space_set_flatview(AddressSpace *as)
+{
+    FlatView *old_view = address_space_to_flatview(as);
+    MemoryRegion *physmr = memory_region_get_flatview_root(as->root);
+    FlatView *new_view = g_hash_table_lookup(flat_views, physmr);
+
+    assert(new_view);
+
+    if (old_view == new_view) {
+        return;
+    }
+
+    if (old_view) {
+        flatview_ref(old_view);
     }
-    mem_commit(new_view->dispatch);
+
+    flatview_ref(new_view);
 
     if (!QTAILQ_EMPTY(&as->listeners)) {
-        address_space_update_topology_pass(as, old_view, new_view, false);
-        address_space_update_topology_pass(as, old_view, new_view, true);
+        FlatView tmpview = { .nr = 0 }, *old_view2 = old_view;
+
+        if (!old_view2) {
+            old_view2 = &tmpview;
+        }
+        address_space_update_topology_pass(as, old_view2, new_view, false);
+        address_space_update_topology_pass(as, old_view2, new_view, true);
     }
 
     /* Writes are protected by the BQL.  */
     atomic_rcu_set(&as->current_map, new_view);
-    flatview_unref(old_view);
+    if (old_view) {
+        flatview_unref(old_view);
+    }
 
     /* Note that all the old MemoryRegions are still alive up to this
      * point.  This relieves most MemoryListeners from the need to
@@ -933,9 +1020,20 @@ static void address_space_update_topology(AddressSpace *as)
      * outside the iothread mutex, in which case precise reference
      * counting is necessary.
      */
-    flatview_unref(old_view);
+    if (old_view) {
+        flatview_unref(old_view);
+    }
+}
 
-    address_space_update_ioeventfds(as);
+static void address_space_update_topology(AddressSpace *as)
+{
+    MemoryRegion *physmr = memory_region_get_flatview_root(as->root);
+
+    flatviews_init();
+    if (!g_hash_table_lookup(flat_views, physmr)) {
+        generate_memory_topology(physmr);
+    }
+    address_space_set_flatview(as);
 }
 
 void memory_region_transaction_begin(void)
@@ -954,12 +1052,16 @@ void memory_region_transaction_commit(void)
     --memory_region_transaction_depth;
     if (!memory_region_transaction_depth) {
         if (memory_region_update_pending) {
+            flatviews_reset();
+
             MEMORY_LISTENER_CALL_GLOBAL(begin, Forward);
 
             QTAILQ_FOREACH(as, &address_spaces, address_spaces_link) {
-                address_space_update_topology(as);
+                address_space_set_flatview(as);
+                address_space_update_ioeventfds(as);
             }
             memory_region_update_pending = false;
+            ioeventfd_update_pending = false;
             MEMORY_LISTENER_CALL_GLOBAL(commit, Forward);
         } else if (ioeventfd_update_pending) {
             QTAILQ_FOREACH(as, &address_spaces, address_spaces_link) {
@@ -1761,7 +1863,7 @@ void memory_region_notify_one(IOMMUNotifier *notifier,
      * Skip the notification if the notification does not overlap
      * with registered range.
      */
-    if (notifier->start > entry->iova + entry->addr_mask + 1 ||
+    if (notifier->start > entry->iova + entry->addr_mask ||
         notifier->end < entry->iova) {
         return;
     }
@@ -2468,20 +2570,14 @@ static void listener_add_address_space(MemoryListener *listener,
 
     view = address_space_get_flatview(as);
     FOR_EACH_FLAT_RANGE(fr, view) {
-        MemoryRegionSection section = {
-            .mr = fr->mr,
-            .fv = view,
-            .offset_within_region = fr->offset_in_region,
-            .size = fr->addr.size,
-            .offset_within_address_space = int128_get64(fr->addr.start),
-            .readonly = fr->readonly,
-        };
-        if (fr->dirty_log_mask && listener->log_start) {
-            listener->log_start(listener, &section, 0, fr->dirty_log_mask);
-        }
+        MemoryRegionSection section = section_from_flat_range(fr, view);
+
         if (listener->region_add) {
             listener->region_add(listener, &section);
         }
+        if (fr->dirty_log_mask && listener->log_start) {
+            listener->log_start(listener, &section, 0, fr->dirty_log_mask);
+        }
     }
     if (listener->commit) {
         listener->commit(listener);
@@ -2646,60 +2742,31 @@ void memory_region_invalidate_mmio_ptr(MemoryRegion *mr, hwaddr offset,
 void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name)
 {
     memory_region_ref(root);
-    memory_region_transaction_begin();
-    as->ref_count = 1;
     as->root = root;
-    as->malloced = false;
-    as->current_map = flatview_new();
+    as->current_map = NULL;
     as->ioeventfd_nb = 0;
     as->ioeventfds = NULL;
     QTAILQ_INIT(&as->listeners);
     QTAILQ_INSERT_TAIL(&address_spaces, as, address_spaces_link);
     as->name = g_strdup(name ? name : "anonymous");
-    memory_region_update_pending |= root->enabled;
-    memory_region_transaction_commit();
+    address_space_update_topology(as);
+    address_space_update_ioeventfds(as);
 }
 
 static void do_address_space_destroy(AddressSpace *as)
 {
-    bool do_free = as->malloced;
-
     assert(QTAILQ_EMPTY(&as->listeners));
 
     flatview_unref(as->current_map);
     g_free(as->name);
     g_free(as->ioeventfds);
     memory_region_unref(as->root);
-    if (do_free) {
-        g_free(as);
-    }
-}
-
-AddressSpace *address_space_init_shareable(MemoryRegion *root, const char *name)
-{
-    AddressSpace *as;
-
-    QTAILQ_FOREACH(as, &address_spaces, address_spaces_link) {
-        if (root == as->root && as->malloced) {
-            as->ref_count++;
-            return as;
-        }
-    }
-
-    as = g_malloc0(sizeof *as);
-    address_space_init(as, root, name);
-    as->malloced = true;
-    return as;
 }
 
 void address_space_destroy(AddressSpace *as)
 {
     MemoryRegion *root = as->root;
 
-    as->ref_count--;
-    if (as->ref_count) {
-        return;
-    }
     /* Flush out anything from MemoryListeners listening in on this */
     memory_region_transaction_begin();
     as->root = NULL;
@@ -2839,18 +2906,44 @@ static void mtree_print_mr(fprintf_function mon_printf, void *f,
     }
 }
 
-static void mtree_print_flatview(fprintf_function p, void *f,
-                                 AddressSpace *as)
+struct FlatViewInfo {
+    fprintf_function mon_printf;
+    void *f;
+    int counter;
+    bool dispatch_tree;
+};
+
+static void mtree_print_flatview(gpointer key, gpointer value,
+                                 gpointer user_data)
 {
-    FlatView *view = address_space_get_flatview(as);
+    FlatView *view = key;
+    GArray *fv_address_spaces = value;
+    struct FlatViewInfo *fvi = user_data;
+    fprintf_function p = fvi->mon_printf;
+    void *f = fvi->f;
     FlatRange *range = &view->ranges[0];
     MemoryRegion *mr;
     int n = view->nr;
+    int i;
+    AddressSpace *as;
+
+    p(f, "FlatView #%d\n", fvi->counter);
+    ++fvi->counter;
+
+    for (i = 0; i < fv_address_spaces->len; ++i) {
+        as = g_array_index(fv_address_spaces, AddressSpace*, i);
+        p(f, " AS \"%s\", root: %s", as->name, memory_region_name(as->root));
+        if (as->root->alias) {
+            p(f, ", alias %s", memory_region_name(as->root->alias));
+        }
+        p(f, "\n");
+    }
+
+    p(f, " Root memory region: %s\n",
+      view->root ? memory_region_name(view->root) : "(none)");
 
     if (n <= 0) {
-        p(f, MTREE_INDENT "No rendered FlatView for "
-          "address space '%s'\n", as->name);
-        flatview_unref(view);
+        p(f, MTREE_INDENT "No rendered FlatView\n\n");
         return;
     }
 
@@ -2877,21 +2970,65 @@ static void mtree_print_flatview(fprintf_function p, void *f,
         range++;
     }
 
+#if !defined(CONFIG_USER_ONLY)
+    if (fvi->dispatch_tree && view->root) {
+        mtree_print_dispatch(p, f, view->dispatch, view->root);
+    }
+#endif
+
+    p(f, "\n");
+}
+
+static gboolean mtree_info_flatview_free(gpointer key, gpointer value,
+                                      gpointer user_data)
+{
+    FlatView *view = key;
+    GArray *fv_address_spaces = value;
+
+    g_array_unref(fv_address_spaces);
     flatview_unref(view);
+
+    return true;
 }
 
-void mtree_info(fprintf_function mon_printf, void *f, bool flatview)
+void mtree_info(fprintf_function mon_printf, void *f, bool flatview,
+                bool dispatch_tree)
 {
     MemoryRegionListHead ml_head;
     MemoryRegionList *ml, *ml2;
     AddressSpace *as;
 
     if (flatview) {
+        FlatView *view;
+        struct FlatViewInfo fvi = {
+            .mon_printf = mon_printf,
+            .f = f,
+            .counter = 0,
+            .dispatch_tree = dispatch_tree
+        };
+        GArray *fv_address_spaces;
+        GHashTable *views = g_hash_table_new(g_direct_hash, g_direct_equal);
+
+        /* Gather all FVs in one table */
         QTAILQ_FOREACH(as, &address_spaces, address_spaces_link) {
-            mon_printf(f, "address-space (flat view): %s\n", as->name);
-            mtree_print_flatview(mon_printf, f, as);
-            mon_printf(f, "\n");
+            view = address_space_get_flatview(as);
+
+            fv_address_spaces = g_hash_table_lookup(views, view);
+            if (!fv_address_spaces) {
+                fv_address_spaces = g_array_new(false, false, sizeof(as));
+                g_hash_table_insert(views, view, fv_address_spaces);
+            }
+
+            g_array_append_val(fv_address_spaces, as);
         }
+
+        /* Print */
+        g_hash_table_foreach(views, mtree_print_flatview, &fvi);
+
+        /* Free */
+        g_hash_table_foreach_remove(views, mtree_info_flatview_free, 0);
+        g_hash_table_unref(views);
+
         return;
     }