From: Jeremy Allison <jra@samba.org>
Date: Wed, 18 Mar 2020 22:59:03 +0000 (-0700)
Subject: s3: smbd: Convert async SMB2 close to use the wait_queue idiom.
X-Git-Tag: ldb-2.2.0~1291
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b686de4e7ba83f6f37b1da175e259d25e75c98d1;p=thirdparty%2Fsamba.git

s3: smbd: Convert async SMB2 close to use the wait_queue idiom.

Use the same mechanism to wait for aio on a handle used by
SMB1 reply_tdis(), reply_ulogoffX(), reply_exit(), reply_close()
and SMB2 tree disconnect.

This removes the last user of fsp->deferred_close, allowing
us to remove it.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
---

diff --git a/source3/smbd/smb2_close.c b/source3/smbd/smb2_close.c
index ae0873e3bbe..09778617884 100644
--- a/source3/smbd/smb2_close.c
+++ b/source3/smbd/smb2_close.c
@@ -301,9 +301,10 @@ struct smbd_smb2_close_state {
 	uint64_t out_allocation_size;
 	uint64_t out_end_of_file;
 	uint32_t out_file_attributes;
+	struct tevent_queue *wait_queue;
 };
 
-static void smbd_smb2_close_do(struct tevent_req *subreq);
+static void smbd_smb2_close_wait_done(struct tevent_req *subreq);
 
 static struct tevent_req *smbd_smb2_close_send(TALLOC_CTX *mem_ctx,
 					       struct tevent_context *ev,
@@ -337,12 +338,41 @@ static struct tevent_req *smbd_smb2_close_send(TALLOC_CTX *mem_ctx,
 	}
 
 	if (in_fsp->num_aio_requests != 0) {
-		in_fsp->deferred_close = tevent_wait_send(in_fsp, ev);
-		if (tevent_req_nomem(in_fsp->deferred_close, req)) {
+		struct tevent_req *subreq;
+
+		state->wait_queue = tevent_queue_create(state,
+					"smbd_smb2_close_send_wait_queue");
+		if (tevent_req_nomem(state->wait_queue, req)) {
+			return tevent_req_post(req, ev);
+		}
+		/*
+		 * Now wait until all aio requests on this fsp are
+		 * finished.
+		 *
+		 * We don't set a callback, as we just want to block the
+		 * wait queue and the talloc_free() of fsp->aio_request
+		 * will remove the item from the wait queue.
+		 */
+		subreq = tevent_queue_wait_send(in_fsp->aio_requests,
+					smb2req->sconn->ev_ctx,
+					state->wait_queue);
+		if (tevent_req_nomem(subreq, req)) {
+			return tevent_req_post(req, ev);
+		}
+
+		/*
+		 * Now we add our own waiter to the end of the queue,
+		 * this way we get notified when all pending requests are
+		 * finished.
+		 */
+		subreq = tevent_queue_wait_send(state,
+					smb2req->sconn->ev_ctx,
+					state->wait_queue);
+		if (tevent_req_nomem(subreq, req)) {
 			return tevent_req_post(req, ev);
 		}
-		tevent_req_set_callback(in_fsp->deferred_close,
-					smbd_smb2_close_do, req);
+
+		tevent_req_set_callback(subreq, smbd_smb2_close_wait_done, req);
 		return req;
 	}
 
@@ -365,24 +395,16 @@ static struct tevent_req *smbd_smb2_close_send(TALLOC_CTX *mem_ctx,
 	return tevent_req_post(req, ev);
 }
 
-static void smbd_smb2_close_do(struct tevent_req *subreq)
+static void smbd_smb2_close_wait_done(struct tevent_req *subreq)
 {
 	struct tevent_req *req = tevent_req_callback_data(
 		subreq, struct tevent_req);
 	struct smbd_smb2_close_state *state = tevent_req_data(
 		req, struct smbd_smb2_close_state);
 	NTSTATUS status;
-	int ret;
 
-	ret = tevent_wait_recv(subreq);
+	tevent_queue_wait_recv(subreq);
 	TALLOC_FREE(subreq);
-	if (ret != 0) {
-		DEBUG(10, ("tevent_wait_recv returned %s\n",
-			   strerror(ret)));
-		/*
-		 * Continue anyway, this should never happen
-		 */
-	}
 
 	status = smbd_smb2_close(state->smb2req,
 				 state->in_fsp,