Commit 34abd408 authored by Stefan Metzmacher's avatar Stefan Metzmacher Committed by Steve French
Browse files

smb: server: make use of smbdirect_socket.send_io.bcredits 



It turns out that our code will corrupt the stream of
reassabled data transfer messages when we trigger an
immendiate (empty) send.

In order to fix this we'll have a single 'batch' credit per
connection. And code getting that credit is free to use
as much messages until remaining_length reaches 0, then
the batch credit it given back and the next logical send can
happen.

Cc: <stable@vger.kernel.org> # 6.18.x
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: default avatarStefan Metzmacher <metze@samba.org>
Acked-by: default avatarNamjae Jeon <linkinjeon@kernel.org>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 8106978d

fs/smb/server/transport_rdma.c

+51 −2
Original line number Diff line number Diff line
@@ -221,6 +221,7 @@ static void smb_direct_disconnect_wake_up_all(struct smbdirect_socket *sc) 
	 * in order to notice the broken connection.

	 */

	wake_up_all(&sc->status_wait);

	wake_up_all(&sc->send_io.bcredits.wait_queue);

	wake_up_all(&sc->send_io.lcredits.wait_queue);

	wake_up_all(&sc->send_io.credits.wait_queue);

	wake_up_all(&sc->send_io.pending.zero_wait_queue);
@@ -1152,6 +1153,7 @@ static void smb_direct_send_ctx_init(struct smbdirect_send_batch *send_ctx, 
	send_ctx->wr_cnt = 0;

	send_ctx->need_invalidate_rkey = need_invalidate_rkey;

	send_ctx->remote_key = remote_key;

	send_ctx->credit = 0;

}



static int smb_direct_flush_send_list(struct smbdirect_socket *sc,
@@ -1159,10 +1161,10 @@ static int smb_direct_flush_send_list(struct smbdirect_socket *sc, 
				      bool is_last)

{

	struct smbdirect_send_io *first, *last;

	int ret;

	int ret = 0;



	if (list_empty(&send_ctx->msg_list))

		return 0;

		goto release_credit;



	first = list_first_entry(&send_ctx->msg_list,

				 struct smbdirect_send_io,
@@ -1204,6 +1206,13 @@ static int smb_direct_flush_send_list(struct smbdirect_socket *sc, 
		smb_direct_free_sendmsg(sc, last);

	}



release_credit:

	if (is_last && !ret && send_ctx->credit) {

		atomic_add(send_ctx->credit, &sc->send_io.bcredits.count);

		send_ctx->credit = 0;

		wake_up(&sc->send_io.bcredits.wait_queue);

	}



	return ret;

}
@@ -1229,6 +1238,25 @@ static int wait_for_credits(struct smbdirect_socket *sc, 
	} while (true);

}



static int wait_for_send_bcredit(struct smbdirect_socket *sc,

				 struct smbdirect_send_batch *send_ctx)

{

	int ret;



	if (send_ctx->credit)

		return 0;



	ret = wait_for_credits(sc,

			       &sc->send_io.bcredits.wait_queue,

			       &sc->send_io.bcredits.count,

			       1);

	if (ret)

		return ret;



	send_ctx->credit = 1;

	return 0;

}



static int wait_for_send_lcredit(struct smbdirect_socket *sc,

				 struct smbdirect_send_batch *send_ctx)

{
@@ -1430,6 +1458,16 @@ static int smb_direct_post_send_data(struct smbdirect_socket *sc, 
	struct smbdirect_send_io *msg;

	int data_length;

	struct scatterlist sg[SMBDIRECT_SEND_IO_MAX_SGE - 1];

	struct smbdirect_send_batch _send_ctx;



	if (!send_ctx) {

		smb_direct_send_ctx_init(&_send_ctx, false, 0);

		send_ctx = &_send_ctx;

	}



	ret = wait_for_send_bcredit(sc, send_ctx);

	if (ret)

		goto bcredit_failed;



	ret = wait_for_send_lcredit(sc, send_ctx);

	if (ret)
@@ -1482,6 +1520,13 @@ static int smb_direct_post_send_data(struct smbdirect_socket *sc, 
	ret = post_sendmsg(sc, send_ctx, msg);

	if (ret)

		goto err;



	if (send_ctx == &_send_ctx) {

		ret = smb_direct_flush_send_list(sc, send_ctx, true);

		if (ret)

			goto err;

	}



	return 0;

err:

	smb_direct_free_sendmsg(sc, msg);
@@ -1490,6 +1535,9 @@ static int smb_direct_post_send_data(struct smbdirect_socket *sc, 
credit_failed:

	atomic_inc(&sc->send_io.lcredits.count);

lcredit_failed:

	atomic_add(send_ctx->credit, &sc->send_io.bcredits.count);

	send_ctx->credit = 0;

bcredit_failed:

	return ret;

}
@@ -1961,6 +2009,7 @@ static int smb_direct_send_negotiate_response(struct smbdirect_socket *sc, 
		resp->max_fragmented_size =

				cpu_to_le32(sp->max_fragmented_recv_size);



		atomic_set(&sc->send_io.bcredits.count, 1);

		sc->recv_io.expected = SMBDIRECT_EXPECT_DATA_TRANSFER;

		sc->status = SMBDIRECT_SOCKET_CONNECTED;

	}