From: Long Li <lon...@microsoft.com>
Similar to sending transfer message with page payload, this function creates a
SMBD data packet and send it over to RDMA, from iov passed from upper layer.
Signed-off-by: Long Li <lon...@microsoft.com>
---
fs/cifs/cifsrdma.c | 119 +++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 119 insertions(+)
diff --git a/fs/cifs/cifsrdma.c b/fs/cifs/cifsrdma.c
index b3ec109..989cad8 100644
--- a/fs/cifs/cifsrdma.c
+++ b/fs/cifs/cifsrdma.c
@@ -66,6 +66,9 @@ static int cifs_rdma_post_recv(
struct cifs_rdma_info *info,
struct cifs_rdma_response *response);
+static int cifs_rdma_post_send_data(
+ struct cifs_rdma_info *info,
+ struct kvec *iov, int n_vec, int remaining_data_length);
static int cifs_rdma_post_send_page(struct cifs_rdma_info *info,
struct page *page, unsigned long offset,
size_t size, int remaining_data_length);
@@ -671,6 +674,122 @@ static int cifs_rdma_post_send_page(struct cifs_rdma_info
*info, struct page *pa
}
/*
+ * Send a data buffer
+ * iov: the iov array describing the data buffers
+ * n_vec: number of iov array
+ * remaining_data_length: remaining data to send in this payload
+ */
+static int cifs_rdma_post_send_data(
+ struct cifs_rdma_info *info, struct kvec *iov, int n_vec,
+ int remaining_data_length)
+{
+ struct cifs_rdma_request *request;
+ struct smbd_data_transfer *packet;
+ struct ib_send_wr send_wr, *send_wr_fail;
+ int rc = -ENOMEM, i;
+ u32 data_length;
+
+ request = mempool_alloc(info->request_mempool, GFP_KERNEL);
+ if (!request)
+ return rc;
+
+ request->info = info;
+
+ wait_event(info->wait_send_queue, atomic_read(&info->send_credits) > 0);
+ atomic_dec(&info->send_credits);
+
+ packet = (struct smbd_data_transfer *) request->packet;
+ packet->credits_requested = cpu_to_le16(info->send_credit_target);
+ packet->flags = cpu_to_le16(0);
+ packet->reserved = cpu_to_le16(0);
+
+ packet->data_offset = cpu_to_le32(24);
+
+ data_length = 0;
+ for (i=0; i<n_vec; i++)
+ data_length += iov[i].iov_len;
+ packet->data_length = cpu_to_le32(data_length);
+
+ packet->remaining_data_length = cpu_to_le32(remaining_data_length);
+ packet->padding = cpu_to_le32(0);
+
+ log_rdma_send("credits_requested=%d credits_granted=%d data_offset=%d "
+ "data_length=%d remaining_data_length=%d\n",
+ le16_to_cpu(packet->credits_requested),
+ le16_to_cpu(packet->credits_granted),
+ le32_to_cpu(packet->data_offset),
+ le32_to_cpu(packet->data_length),
+ le32_to_cpu(packet->remaining_data_length));
+
+ request->sge = kzalloc(sizeof(struct ib_sge)*(n_vec+1), GFP_KERNEL);
+ if (!request->sge)
+ goto allocate_sge_failed;
+
+ request->num_sge = n_vec+1;
+
+ request->sge[0].addr = ib_dma_map_single(
+ info->id->device, (void *)packet,
+ sizeof(*packet), DMA_BIDIRECTIONAL);
+ if(ib_dma_mapping_error(info->id->device, request->sge[0].addr)) {
+ rc = -EIO;
+ goto dma_mapping_failure;
+ }
+ request->sge[0].length = sizeof(*packet);
+ request->sge[0].lkey = info->pd->local_dma_lkey;
+ ib_dma_sync_single_for_device(info->id->device, request->sge[0].addr,
+ request->sge[0].length, DMA_TO_DEVICE);
+
+ for (i=0; i<n_vec; i++) {
+ request->sge[i+1].addr = ib_dma_map_single(info->id->device,
iov[i].iov_base,
+ iov[i].iov_len,
DMA_BIDIRECTIONAL);
+ if(ib_dma_mapping_error(info->id->device,
request->sge[i+1].addr)) {
+ rc = -EIO;
+ goto dma_mapping_failure;
+ }
+ request->sge[i+1].length = iov[i].iov_len;
+ request->sge[i+1].lkey = info->pd->local_dma_lkey;
+ ib_dma_sync_single_for_device(info->id->device,
request->sge[i+i].addr,
+ request->sge[i+i].length, DMA_TO_DEVICE);
+ }
+
+ log_rdma_send("rdma_request sge[0] addr=%llu legnth=%u lkey=%u\n",
+ request->sge[0].addr, request->sge[0].length,
request->sge[0].lkey);
+ for (i=0; i<n_vec; i++)
+ log_rdma_send("rdma_request sge[%d] addr=%llu legnth=%u
lkey=%u\n",
+ i+1, request->sge[i+1].addr,
+ request->sge[i+1].length, request->sge[i+1].lkey);
+
+ request->cqe.done = send_done;
+
+ send_wr.next = NULL;
+ send_wr.wr_cqe = &request->cqe;
+ send_wr.sg_list = request->sge;
+ send_wr.num_sge = request->num_sge;
+ send_wr.opcode = IB_WR_SEND;
+ send_wr.send_flags = IB_SEND_SIGNALED;
+
+ rc = ib_post_send(info->id->qp, &send_wr, &send_wr_fail);
+ if (!rc)
+ return 0;
+
+ // post send failed
+ log_rdma_send("ib_post_send failed rc=%d\n", rc);
+
+dma_mapping_failure:
+ for (i=0; i<n_vec+1; i++)
+ if (request->sge[i].addr)
+ ib_dma_unmap_single(info->id->device,
+ request->sge[i].addr,
+ request->sge[i].length,
+ DMA_TO_DEVICE);
+ kfree(request->sge);
+
+allocate_sge_failed:
+ mempool_free(request, info->request_mempool);
+ return rc;
+}
+
+/*
* Post a receive request to the transport
* The remote peer can only send data when a receive is posted
* The interaction is controlled by send/recieve credit system
--
2.7.4
