[v3,05/25] tools/xenstore: rename do_tdb_write() and change parameter type

Commit Message

Jürgen Groß July 24, 2023, 11:02 a.m. UTC

Rename do_tdb_write() to db_write() and replace the key parameter with
db_name specifying the name of the node in the data base, and the data
parameter with a data pointer and a length.

Do the same key parameter type change for write_node_raw(), too.

This is in preparation to replace TDB with a more simple data storage.

Signed-off-by: Juergen Gross <[e-mail]>
Reviewed-by: Julien Grall <[e-mail]>
---
V2:
- keep ta_key in finalize_transaction() (Julien Grall)
---
 tools/xenstore/xenstored_core.c        | 70 +++++++++++++-------------
 tools/xenstore/xenstored_core.h        | 11 ++--
 tools/xenstore/xenstored_domain.c      |  4 +-
 tools/xenstore/xenstored_transaction.c | 10 ++--
 4 files changed, 46 insertions(+), 49 deletions(-)

Patch

diff --git a/tools/xenstore/xenstored_core.c b/tools/xenstore/xenstored_core.c
index aa3885682d..2aa3d37c18 100644
--- a/tools/xenstore/xenstored_core.c
+++ b/tools/xenstore/xenstored_core.c
@@ -600,23 +600,27 @@  static unsigned int get_acc_domid(struct connection *conn, TDB_DATA *key,
 	       ? domid : conn->id;
 }
 
-int do_tdb_write(struct connection *conn, TDB_DATA *key, TDB_DATA *data,
-		 struct node_account_data *acc, enum write_node_mode mode,
-		 bool no_quota_check)
+int db_write(struct connection *conn, const char *db_name, void *data,
+	     size_t size, struct node_account_data *acc,
+	     enum write_node_mode mode, bool no_quota_check)
 {
-	struct xs_tdb_record_hdr *hdr = (void *)data->dptr;
+	struct xs_tdb_record_hdr *hdr = data;
 	struct node_account_data old_acc = {};
 	unsigned int old_domid, new_domid;
 	int ret;
+	TDB_DATA key, dat;
 
+	set_tdb_key(db_name, &key);
+	dat.dptr = data;
+	dat.dsize = size;
 	if (!acc)
 		old_acc.memory = -1;
 	else
 		old_acc = *acc;
 
-	get_acc_data(key, &old_acc);
-	old_domid = get_acc_domid(conn, key, old_acc.domid);
-	new_domid = get_acc_domid(conn, key, hdr->perms[0].id);
+	get_acc_data(&key, &old_acc);
+	old_domid = get_acc_domid(conn, &key, old_acc.domid);
+	new_domid = get_acc_domid(conn, &key, hdr->perms[0].id);
 
 	/*
 	 * Don't check for ENOENT, as we want to be able to switch orphaned
@@ -624,35 +628,34 @@  int do_tdb_write(struct connection *conn, TDB_DATA *key, TDB_DATA *data,
 	 */
 	if (old_acc.memory)
 		domain_memory_add_nochk(conn, old_domid,
-					-old_acc.memory - key->dsize);
-	ret = domain_memory_add(conn, new_domid,
-				data->dsize + key->dsize, no_quota_check);
+					-old_acc.memory - key.dsize);
+	ret = domain_memory_add(conn, new_domid, size + key.dsize,
+				no_quota_check);
 	if (ret) {
 		/* Error path, so no quota check. */
 		if (old_acc.memory)
 			domain_memory_add_nochk(conn, old_domid,
-						old_acc.memory + key->dsize);
+						old_acc.memory + key.dsize);
 		return ret;
 	}
 
 	/* TDB should set errno, but doesn't even set ecode AFAICT. */
-	if (tdb_store(tdb_ctx, *key, *data,
+	if (tdb_store(tdb_ctx, key, dat,
 		      (mode == NODE_CREATE) ? TDB_INSERT : TDB_MODIFY) != 0) {
-		domain_memory_add_nochk(conn, new_domid,
-					-data->dsize - key->dsize);
+		domain_memory_add_nochk(conn, new_domid, -size - key.dsize);
 		/* Error path, so no quota check. */
 		if (old_acc.memory)
 			domain_memory_add_nochk(conn, old_domid,
-						old_acc.memory + key->dsize);
+						old_acc.memory + key.dsize);
 		errno = EIO;
 		return errno;
 	}
-	trace_tdb("store %s size %zu\n", key->dptr, data->dsize + key->dsize);
+	trace_tdb("store %s size %zu\n", db_name, size + key.dsize);
 
 	if (acc) {
 		/* Don't use new_domid, as it might be a transaction node. */
 		acc->domid = hdr->perms[0].id;
-		acc->memory = data->dsize;
+		acc->memory = size;
 	}
 
 	return 0;
@@ -780,33 +783,35 @@  static bool read_node_can_propagate_errno(void)
 	return errno == ENOMEM || errno == ENOSPC;
 }
 
-int write_node_raw(struct connection *conn, TDB_DATA *key, struct node *node,
-		   enum write_node_mode mode, bool no_quota_check)
+int write_node_raw(struct connection *conn, const char *db_name,
+		   struct node *node, enum write_node_mode mode,
+		   bool no_quota_check)
 {
-	TDB_DATA data;
+	void *data;
+	size_t size;
 	void *p;
 	struct xs_tdb_record_hdr *hdr;
 
 	if (domain_adjust_node_perms(node))
 		return errno;
 
-	data.dsize = sizeof(*hdr)
+	size = sizeof(*hdr)
 		+ node->perms.num * sizeof(node->perms.p[0])
 		+ node->datalen + node->childlen;
 
 	/* Call domain_max_chk() in any case in order to record max values. */
-	if (domain_max_chk(conn, ACC_NODESZ, data.dsize) && !no_quota_check) {
+	if (domain_max_chk(conn, ACC_NODESZ, size) && !no_quota_check) {
 		errno = ENOSPC;
 		return errno;
 	}
 
-	data.dptr = talloc_size(node, data.dsize);
-	if (!data.dptr) {
+	data = talloc_size(node, size);
+	if (!data) {
 		errno = ENOMEM;
 		return errno;
 	}
 
-	hdr = (void *)data.dptr;
+	hdr = data;
 	hdr->generation = node->generation;
 	hdr->num_perms = node->perms.num;
 	hdr->datalen = node->datalen;
@@ -819,7 +824,8 @@  int write_node_raw(struct connection *conn, TDB_DATA *key, struct node *node,
 	p += node->datalen;
 	memcpy(p, node->children, node->childlen);
 
-	if (do_tdb_write(conn, key, &data, &node->acc, mode, no_quota_check))
+	if (db_write(conn, db_name, data, size, &node->acc, mode,
+		     no_quota_check))
 		return EIO;
 
 	return 0;
@@ -833,13 +839,11 @@  static int write_node(struct connection *conn, struct node *node,
 		      enum write_node_mode mode, bool no_quota_check)
 {
 	int ret;
-	TDB_DATA key;
 
 	if (access_node(conn, node, NODE_ACCESS_WRITE, &node->db_name))
 		return errno;
 
-	set_tdb_key(node->db_name, &key);
-	ret = write_node_raw(conn, &key, node, mode, no_quota_check);
+	ret = write_node_raw(conn, node->db_name, node, mode, no_quota_check);
 	if (ret && conn && conn->transaction) {
 		/*
 		 * Reverting access_node() is hard, so just fail the
@@ -3429,7 +3433,6 @@  void read_state_node(const void *ctx, const void *state)
 {
 	const struct xs_state_node *sn = state;
 	struct node *node, *parent;
-	TDB_DATA key;
 	char *name, *parentname;
 	unsigned int i;
 	struct connection conn = { .id = priv_domid };
@@ -3482,15 +3485,12 @@  void read_state_node(const void *ctx, const void *state)
 		if (add_child(node, parent, name))
 			barf("allocation error restoring node");
 
-		set_tdb_key(parentname, &key);
-		if (write_node_raw(NULL, &key, parent, NODE_MODIFY, true))
+		if (write_node_raw(NULL, parentname, parent, NODE_MODIFY, true))
 			barf("write parent error restoring node");
 	}
 
-	set_tdb_key(name, &key);
-
 	/* The "/" node is already existing, so it can only be modified here. */
-	if (write_node_raw(NULL, &key, node,
+	if (write_node_raw(NULL, name, node,
 			   strcmp(name, "/") ? NODE_CREATE : NODE_MODIFY, true))
 		barf("write node error restoring node");
 
diff --git a/tools/xenstore/xenstored_core.h b/tools/xenstore/xenstored_core.h
index 1aae324c77..875ee5192b 100644
--- a/tools/xenstore/xenstored_core.h
+++ b/tools/xenstore/xenstored_core.h
@@ -243,8 +243,9 @@  enum write_node_mode {
 	NODE_MODIFY
 };
 
-int write_node_raw(struct connection *conn, TDB_DATA *key, struct node *node,
-		   enum write_node_mode mode, bool no_quota_check);
+int write_node_raw(struct connection *conn, const char *db_name,
+		   struct node *node, enum write_node_mode mode,
+		   bool no_quota_check);
 
 /* Get a node from the tdb data base. */
 struct node *read_node(struct connection *conn, const void *ctx,
@@ -364,9 +365,9 @@  int remember_string(struct hashtable *hash, const char *str);
 
 /* Data base access functions. */
 void set_tdb_key(const char *name, TDB_DATA *key);
-int do_tdb_write(struct connection *conn, TDB_DATA *key, TDB_DATA *data,
-		 struct node_account_data *acc, enum write_node_mode mode,
-		 bool no_quota_check);
+int db_write(struct connection *conn, const char *db_name, void *data,
+	     size_t size, struct node_account_data *acc,
+	     enum write_node_mode mode, bool no_quota_check);
 int db_delete(struct connection *conn, const char *name,
 	      struct node_account_data *acc);
 
diff --git a/tools/xenstore/xenstored_domain.c b/tools/xenstore/xenstored_domain.c
index 569c3bfbd0..10d2280f84 100644
--- a/tools/xenstore/xenstored_domain.c
+++ b/tools/xenstore/xenstored_domain.c
@@ -511,19 +511,17 @@  static int domain_tree_remove_sub(const void *ctx, struct connection *conn,
 				  struct node *node, void *arg)
 {
 	struct domain *domain = arg;
-	TDB_DATA key;
 	int ret = WALK_TREE_OK;
 
 	if (node->perms.p[0].id != domain->domid)
 		return WALK_TREE_OK;
 
 	if (keep_orphans) {
-		set_tdb_key(node->name, &key);
 		domain_nbentry_dec(NULL, domain->domid);
 		node->perms.p[0].id = priv_domid;
 		node->acc.memory = 0;
 		domain_nbentry_inc(NULL, priv_domid);
-		if (write_node_raw(NULL, &key, node, NODE_MODIFY, true)) {
+		if (write_node_raw(NULL, node->name, node, NODE_MODIFY, true)) {
 			/* That's unfortunate. We only can try to continue. */
 			syslog(LOG_ERR,
 			       "error when moving orphaned node %s to dom0\n",
diff --git a/tools/xenstore/xenstored_transaction.c b/tools/xenstore/xenstored_transaction.c
index 4a243369b0..1961aef0d7 100644
--- a/tools/xenstore/xenstored_transaction.c
+++ b/tools/xenstore/xenstored_transaction.c
@@ -228,7 +228,6 @@  int access_node(struct connection *conn, struct node *node,
 {
 	struct accessed_node *i = NULL;
 	struct transaction *trans;
-	TDB_DATA local_key;
 	int ret;
 	bool introduce = false;
 
@@ -286,8 +285,7 @@  int access_node(struct connection *conn, struct node *node,
 			i->generation = node->generation;
 			i->check_gen = true;
 			if (node->generation != NO_GENERATION) {
-				set_tdb_key(i->trans_name, &local_key);
-				ret = write_node_raw(conn, &local_key, node,
+				ret = write_node_raw(conn, i->trans_name, node,
 						     NODE_CREATE, true);
 				if (ret)
 					goto err;
@@ -405,9 +403,9 @@  static int finalize_transaction(struct connection *conn,
 				hdr->generation = ++generation;
 				mode = (i->generation == NO_GENERATION)
 				       ? NODE_CREATE : NODE_MODIFY;
-				set_tdb_key(i->node, &key);
-				*is_corrupt |= do_tdb_write(conn, &key, &data,
-							    NULL, mode, true);
+				*is_corrupt |= db_write(conn, i->node,
+							data.dptr, data.dsize,
+							NULL, mode, true);
 				talloc_free(data.dptr);
 				if (db_delete(conn, i->trans_name, NULL))
 					*is_corrupt = true;