Commit 2dad0b15 authored by Stefan Metzmacher's avatar Stefan Metzmacher Committed by Steve French
Browse files

smb: client: let smbd_post_send_iter() call ib_dma_map_single() for the header first 



This will simplify further changes, the important part is that
request->num_sge >= 1 is only set if request->sge[0].* is valid.

Note that ib_dma_sync_single_for_device() is called in
smbd_post_send() for each sge, so the device will still
see the packet header even if it's modified after calling
ib_dma_map_single().

Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Long Li <longli@microsoft.com>
Acked-by: default avatarNamjae Jeon <linkinjeon@kernel.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: default avatarStefan Metzmacher <metze@samba.org>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent c4709e61

fs/smb/client/smbdirect.c

+21 −22
Original line number Diff line number Diff line
@@ -1158,10 +1158,30 @@ static int smbd_post_send_iter(struct smbdirect_socket *sc, 
	request->socket = sc;

	memset(request->sge, 0, sizeof(request->sge));



	/* Map the packet to DMA */

	header_length = sizeof(struct smbdirect_data_transfer);

	/* If this is a packet without payload, don't send padding */

	if (!iter)

		header_length = offsetof(struct smbdirect_data_transfer, padding);



	packet = smbdirect_send_io_payload(request);

	request->sge[0].addr = ib_dma_map_single(sc->ib.dev,

						 (void *)packet,

						 header_length,

						 DMA_TO_DEVICE);

	if (ib_dma_mapping_error(sc->ib.dev, request->sge[0].addr)) {

		rc = -EIO;

		goto err_dma;

	}



	request->sge[0].length = header_length;

	request->sge[0].lkey = sc->ib.pd->local_dma_lkey;

	request->num_sge = 1;



	/* Fill in the data payload to find out how much data we can add */

	if (iter) {

		struct smb_extract_to_rdma extract = {

			.nr_sge		= 1,

			.nr_sge		= request->num_sge,

			.max_sge	= SMBDIRECT_SEND_IO_MAX_SGE,

			.sge		= request->sge,

			.device		= sc->ib.dev,
@@ -1180,11 +1200,9 @@ static int smbd_post_send_iter(struct smbdirect_socket *sc, 
		*_remaining_data_length -= data_length;

	} else {

		data_length = 0;

		request->num_sge = 1;

	}



	/* Fill in the packet header */

	packet = smbdirect_send_io_payload(request);

	packet->credits_requested = cpu_to_le16(sp->send_credit_target);



	new_credits = manage_credits_prior_sending(sc);
@@ -1211,25 +1229,6 @@ static int smbd_post_send_iter(struct smbdirect_socket *sc, 
		     le32_to_cpu(packet->data_length),

		     le32_to_cpu(packet->remaining_data_length));



	/* Map the packet to DMA */

	header_length = sizeof(struct smbdirect_data_transfer);

	/* If this is a packet without payload, don't send padding */

	if (!data_length)

		header_length = offsetof(struct smbdirect_data_transfer, padding);



	request->sge[0].addr = ib_dma_map_single(sc->ib.dev,

						 (void *)packet,

						 header_length,

						 DMA_TO_DEVICE);

	if (ib_dma_mapping_error(sc->ib.dev, request->sge[0].addr)) {

		rc = -EIO;

		request->sge[0].addr = 0;

		goto err_dma;

	}



	request->sge[0].length = header_length;

	request->sge[0].lkey = sc->ib.pd->local_dma_lkey;



	rc = smbd_post_send(sc, request);

	if (!rc)

		return 0;