X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=ovsdb%2Ftransaction.c;h=137ae06b7c9bffe383ab36b96881b4ff208076ff;hb=3612b72c3639f22b33786c2fac3fb291ff9f6061;hp=d5e3601678b3bf3ccd4599e32999ba8e734eabea;hpb=58fda1dab104041fc693032475ec4662c1a52849;p=openvswitch

diff --git a/ovsdb/transaction.c b/ovsdb/transaction.c
index d5e36016..137ae06b 100644
--- a/ovsdb/transaction.c
+++ b/ovsdb/transaction.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2009 Nicira Networks
+/* Copyright (c) 2009, 2010 Nicira Networks
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,9 +19,11 @@
 
 #include <assert.h>
 
+#include "dynamic-string.h"
 #include "hash.h"
 #include "hmap.h"
 #include "json.h"
+#include "list.h"
 #include "ovsdb-error.h"
 #include "ovsdb.h"
 #include "row.h"
@@ -30,12 +32,13 @@
 
 struct ovsdb_txn {
     struct ovsdb *db;
-    struct hmap txn_tables;     /* Contains "struct ovsdb_txn_table"s. */
+    struct list txn_tables;     /* Contains "struct ovsdb_txn_table"s. */
+    struct ds comment;
 };
 
 /* A table modified by a transaction. */
 struct ovsdb_txn_table {
-    struct hmap_node hmap_node; /* Element in ovsdb_txn's txn_tables hmap. */
+    struct list node;           /* Element in ovsdb_txn's txn_tables list. */
     struct ovsdb_table *table;
     struct hmap txn_rows;       /* Contains "struct ovsdb_txn_row"s. */
 };
@@ -64,7 +67,8 @@ ovsdb_txn_create(struct ovsdb *db)
 {
     struct ovsdb_txn *txn = xmalloc(sizeof *txn);
     txn->db = db;
-    hmap_init(&txn->txn_tables);
+    list_init(&txn->txn_tables);
+    ds_init(&txn->comment);
     return txn;
 }
 
@@ -73,15 +77,17 @@ ovsdb_txn_destroy(struct ovsdb_txn *txn, void (*cb)(struct ovsdb_txn_row *))
 {
     struct ovsdb_txn_table *txn_table, *next_txn_table;
 
-    HMAP_FOR_EACH_SAFE (txn_table, next_txn_table,
-                        struct ovsdb_txn_table, hmap_node, &txn->txn_tables)
-    {
+    LIST_FOR_EACH_SAFE (txn_table, next_txn_table,
+                        struct ovsdb_txn_table, node, &txn->txn_tables) {
         struct ovsdb_txn_row *txn_row, *next_txn_row;
 
         HMAP_FOR_EACH_SAFE (txn_row, next_txn_row,
                             struct ovsdb_txn_row, hmap_node,
                             &txn_table->txn_rows)
         {
+            if (txn_row->old) {
+                txn_row->old->txn_row = NULL;
+            }
             if (txn_row->new) {
                 txn_row->new->txn_row = NULL;
             }
@@ -89,10 +95,11 @@ ovsdb_txn_destroy(struct ovsdb_txn *txn, void (*cb)(struct ovsdb_txn_row *))
             free(txn_row);
         }
 
+        txn_table->table->txn_table = NULL;
         hmap_destroy(&txn_table->txn_rows);
         free(txn_table);
     }
-    hmap_destroy(&txn->txn_tables);
+    ds_destroy(&txn->comment);
     free(txn);
 }
 
@@ -124,12 +131,169 @@ ovsdb_txn_row_commit(struct ovsdb_txn_row *txn_row)
     ovsdb_row_destroy(txn_row->old);
 }
 
+static struct ovsdb_txn_row *
+find_txn_row(const struct ovsdb_table *table, const struct uuid *uuid)
+{
+    struct ovsdb_txn_row *txn_row;
+
+    if (!table->txn_table) {
+        return NULL;
+    }
+
+    HMAP_FOR_EACH_WITH_HASH (txn_row, struct ovsdb_txn_row, hmap_node,
+                             uuid_hash(uuid), &table->txn_table->txn_rows) {
+        const struct ovsdb_row *row;
+
+        row = txn_row->old ? txn_row->old : txn_row->new;
+        if (uuid_equals(uuid, ovsdb_row_get_uuid(row))) {
+            return txn_row;
+        }
+    }
+
+    return NULL;
+}
+
+static void
+ovsdb_txn_adjust_atom_refs(const union ovsdb_atom *atoms, unsigned int n,
+                           const struct ovsdb_table *table,
+                           int delta, struct ovsdb_error **errorp)
+{
+    unsigned int i;
+
+    for (i = 0; i < n; i++) {
+        const struct uuid *uuid = &atoms[i].uuid;
+        struct ovsdb_txn_row *txn_row = find_txn_row(table, uuid);
+        if (txn_row) {
+            if (txn_row->old) {
+                txn_row->old->n_refs += delta;
+            }
+            if (txn_row->new) {
+                txn_row->new->n_refs += delta;
+            }
+        } else {
+            const struct ovsdb_row *row_ = ovsdb_table_get_row(table, uuid);
+            if (row_) {
+                struct ovsdb_row *row = (struct ovsdb_row *) row_;
+                row->n_refs += delta;
+            } else if (errorp) {
+                if (!*errorp) {
+                    *errorp = ovsdb_error("referential integrity violation",
+                                          "reference to nonexistent row "
+                                          UUID_FMT, UUID_ARGS(uuid));
+                }
+            } else {
+                NOT_REACHED();
+            }
+        }
+    }
+}
+
+static void
+ovsdb_txn_adjust_row_refs(const struct ovsdb_row *r,
+                          const struct ovsdb_column *column, int delta,
+                          struct ovsdb_error **errorp)
+{
+    const struct ovsdb_datum *field = &r->fields[column->index];
+    const struct ovsdb_type *type = &column->type;
+
+    if (type->key.type == OVSDB_TYPE_UUID && type->key.u.uuid.refTable) {
+        ovsdb_txn_adjust_atom_refs(field->keys, field->n,
+                                   type->key.u.uuid.refTable, delta, errorp);
+    }
+    if (type->value.type == OVSDB_TYPE_UUID && type->value.u.uuid.refTable) {
+        ovsdb_txn_adjust_atom_refs(field->values, field->n,
+                                   type->value.u.uuid.refTable, delta, errorp);
+    }
+}
+
+static struct ovsdb_error * WARN_UNUSED_RESULT
+ovsdb_txn_adjust_ref_counts__(struct ovsdb_txn *txn, int delta)
+{
+    struct ovsdb_txn_table *t;
+    struct ovsdb_error *error;
+
+    error = NULL;
+    LIST_FOR_EACH (t, struct ovsdb_txn_table, node, &txn->txn_tables) {
+        struct ovsdb_table *table = t->table;
+        struct ovsdb_txn_row *r;
+
+        HMAP_FOR_EACH (r, struct ovsdb_txn_row, hmap_node, &t->txn_rows) {
+            struct shash_node *node;
+
+            SHASH_FOR_EACH (node, &table->schema->columns) {
+                const struct ovsdb_column *column = node->data;
+
+                if (r->old) {
+                    ovsdb_txn_adjust_row_refs(r->old, column, -delta, NULL);
+                }
+                if (r->new) {
+                    ovsdb_txn_adjust_row_refs(r->new, column, delta, &error);
+                }
+            }
+        }
+    }
+    return error;
+}
+
+static void
+ovsdb_txn_rollback_counts(struct ovsdb_txn *txn)
+{
+    ovsdb_error_destroy(ovsdb_txn_adjust_ref_counts__(txn, -1));
+}
+
+static struct ovsdb_error * WARN_UNUSED_RESULT
+ovsdb_txn_commit_ref_counts(struct ovsdb_txn *txn)
+{
+    struct ovsdb_error *error = ovsdb_txn_adjust_ref_counts__(txn, 1);
+    if (error) {
+        ovsdb_txn_rollback_counts(txn);
+    }
+    return error;
+}
+
+static struct ovsdb_error * WARN_UNUSED_RESULT
+update_ref_counts(struct ovsdb_txn *txn)
+{
+    struct ovsdb_error *error;
+    struct ovsdb_txn_table *t;
+
+    error = ovsdb_txn_commit_ref_counts(txn);
+    if (error) {
+        return error;
+    }
+
+    LIST_FOR_EACH (t, struct ovsdb_txn_table, node, &txn->txn_tables) {
+        struct ovsdb_txn_row *r;
+
+        HMAP_FOR_EACH (r, struct ovsdb_txn_row, hmap_node, &t->txn_rows) {
+            if (!r->new && r->old->n_refs) {
+                error = ovsdb_error("referential integrity violation",
+                                    "cannot delete %s row "UUID_FMT" because "
+                                    "of %zu remaining reference(s)",
+                                    t->table->schema->name,
+                                    UUID_ARGS(ovsdb_row_get_uuid(r->old)),
+                                    r->old->n_refs);
+                ovsdb_txn_rollback_counts(txn);
+                return error;
+            }
+        }
+    }
+
+    return NULL;
+}
+
 struct ovsdb_error *
 ovsdb_txn_commit(struct ovsdb_txn *txn, bool durable)
 {
     struct ovsdb_replica *replica;
     struct ovsdb_error *error;
 
+    error = update_ref_counts(txn);
+    if (error) {
+        ovsdb_txn_abort(txn);
+        return error;
+    }
+
     LIST_FOR_EACH (replica, struct ovsdb_replica, node, &txn->db->replicas) {
         error = (replica->class->commit)(replica, txn, durable);
         if (error) {
@@ -154,7 +318,7 @@ ovsdb_txn_for_each_change(const struct ovsdb_txn *txn,
     struct ovsdb_txn_table *t;
     struct ovsdb_txn_row *r;
 
-    HMAP_FOR_EACH (t, struct ovsdb_txn_table, hmap_node, &txn->txn_tables) {
+    LIST_FOR_EACH (t, struct ovsdb_txn_table, node, &txn->txn_tables) {
         HMAP_FOR_EACH (r, struct ovsdb_txn_row, hmap_node, &t->txn_rows) {
             if (!cb(r->old, r->new, aux)) {
                 break;
@@ -164,56 +328,33 @@ ovsdb_txn_for_each_change(const struct ovsdb_txn *txn,
 }
 
 static struct ovsdb_txn_table *
-ovsdb_txn_get_txn_table__(struct ovsdb_txn *txn,
-                          const struct ovsdb_table *table,
-                          uint32_t hash)
+ovsdb_txn_create_txn_table(struct ovsdb_txn *txn, struct ovsdb_table *table)
 {
-    struct ovsdb_txn_table *txn_table;
-
-    HMAP_FOR_EACH_IN_BUCKET (txn_table, struct ovsdb_txn_table, hmap_node,
-                             hash, &txn->txn_tables) {
-        if (txn_table->table == table) {
-            return txn_table;
-        }
-    }
-
-    return NULL;
-}
-
-static struct ovsdb_txn_table *
-ovsdb_txn_get_txn_table(struct ovsdb_txn *txn, const struct ovsdb_table *table)
-{
-    return ovsdb_txn_get_txn_table__(txn, table, hash_pointer(table, 0));
-}
-
-static struct ovsdb_txn_table *
-ovsdb_txn_create_txn_table(struct ovsdb_txn *txn,
-                           struct ovsdb_table *table)
-{
-    uint32_t hash = hash_pointer(table, 0);
-    struct ovsdb_txn_table *txn_table;
+    if (!table->txn_table) {
+        struct ovsdb_txn_table *txn_table;
 
-    txn_table = ovsdb_txn_get_txn_table__(txn, table, hash);
-    if (!txn_table) {
-        txn_table = xmalloc(sizeof *txn_table);
+        table->txn_table = txn_table = xmalloc(sizeof *table->txn_table);
         txn_table->table = table;
         hmap_init(&txn_table->txn_rows);
-        hmap_insert(&txn->txn_tables, &txn_table->hmap_node, hash);
+        list_push_back(&txn->txn_tables, &txn_table->node);
     }
-    return txn_table;
+    return table->txn_table;
 }
 
 static struct ovsdb_txn_row *
-ovsdb_txn_row_create(struct ovsdb_txn_table *txn_table,
+ovsdb_txn_row_create(struct ovsdb_txn *txn, struct ovsdb_table *table,
                      const struct ovsdb_row *old, struct ovsdb_row *new)
 {
-    uint32_t hash = ovsdb_row_hash(old ? old : new);
+    struct ovsdb_txn_table *txn_table;
     struct ovsdb_txn_row *txn_row;
 
     txn_row = xmalloc(sizeof *txn_row);
     txn_row->old = (struct ovsdb_row *) old;
     txn_row->new = new;
-    hmap_insert(&txn_table->txn_rows, &txn_row->hmap_node, hash);
+
+    txn_table = ovsdb_txn_create_txn_table(txn, table);
+    hmap_insert(&txn_table->txn_rows, &txn_row->hmap_node,
+                ovsdb_row_hash(old ? old : new));
 
     return txn_row;
 }
@@ -228,13 +369,12 @@ ovsdb_txn_row_modify(struct ovsdb_txn *txn, const struct ovsdb_row *ro_row_)
         return ro_row;
     } else {
         struct ovsdb_table *table = ro_row->table;
-        struct ovsdb_txn_table *txn_table;
         struct ovsdb_row *rw_row;
 
-        txn_table = ovsdb_txn_create_txn_table(txn, table);
         rw_row = ovsdb_row_clone(ro_row);
+        rw_row->n_refs = ro_row->n_refs;
         uuid_generate(ovsdb_row_get_version_rw(rw_row));
-        rw_row->txn_row = ovsdb_txn_row_create(txn_table, ro_row, rw_row);
+        rw_row->txn_row = ovsdb_txn_row_create(txn, table, ro_row, rw_row);
         hmap_replace(&table->rows, &ro_row->hmap_node, &rw_row->hmap_node);
 
         return rw_row;
@@ -246,12 +386,10 @@ ovsdb_txn_row_insert(struct ovsdb_txn *txn, struct ovsdb_row *row)
 {
     uint32_t hash = ovsdb_row_hash(row);
     struct ovsdb_table *table = row->table;
-    struct ovsdb_txn_table *txn_table;
 
     uuid_generate(ovsdb_row_get_version_rw(row));
 
-    txn_table = ovsdb_txn_create_txn_table(txn, table);
-    row->txn_row = ovsdb_txn_row_create(txn_table, NULL, row);
+    row->txn_row = ovsdb_txn_row_create(txn, table, NULL, row);
     hmap_insert(&table->rows, &row->hmap_node, hash);
 }
 
@@ -263,21 +401,34 @@ ovsdb_txn_row_delete(struct ovsdb_txn *txn, const struct ovsdb_row *row_)
     struct ovsdb_row *row = (struct ovsdb_row *) row_;
     struct ovsdb_table *table = row->table;
     struct ovsdb_txn_row *txn_row = row->txn_row;
-    struct ovsdb_txn_table *txn_table;
 
     hmap_remove(&table->rows, &row->hmap_node);
 
     if (!txn_row) {
-        txn_table = ovsdb_txn_create_txn_table(txn, table);
-        row->txn_row = ovsdb_txn_row_create(txn_table, row, NULL);
+        row->txn_row = ovsdb_txn_row_create(txn, table, row, NULL);
     } else {
         assert(txn_row->new == row);
         if (txn_row->old) {
             txn_row->new = NULL;
         } else {
-            txn_table = ovsdb_txn_get_txn_table(txn, table);
-            hmap_remove(&txn_table->txn_rows, &txn_row->hmap_node);
+            hmap_remove(&table->txn_table->txn_rows, &txn_row->hmap_node);
+            free(txn_row);
         }
         ovsdb_row_destroy(row);
     }
 }
+
+void
+ovsdb_txn_add_comment(struct ovsdb_txn *txn, const char *s)
+{
+    if (txn->comment.length) {
+        ds_put_char(&txn->comment, '\n');
+    }
+    ds_put_cstr(&txn->comment, s);
+}
+
+const char *
+ovsdb_txn_get_comment(const struct ovsdb_txn *txn)
+{
+    return txn->comment.length ? ds_cstr_ro(&txn->comment) : NULL;
+}