svcrdma: Move the DMA unmap logic to the CQ handler
Separate DMA unmap from context destruction and perform DMA unmapping
in the SQ/RQ CQ reap functions. This is necessary to support software
based RDMA implementations that actually copy the data in their
ib_dma_unmap callback functions and architectures that don't have
cache coherent I/O busses.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
index fc86338..7e8ee66 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -150,6 +150,18 @@
return ctxt;
}
+static void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt)
+{
+ struct svcxprt_rdma *xprt = ctxt->xprt;
+ int i;
+ for (i = 0; i < ctxt->count && ctxt->sge[i].length; i++) {
+ ib_dma_unmap_single(xprt->sc_cm_id->device,
+ ctxt->sge[i].addr,
+ ctxt->sge[i].length,
+ ctxt->direction);
+ }
+}
+
void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages)
{
struct svcxprt_rdma *xprt;
@@ -161,12 +173,6 @@
for (i = 0; i < ctxt->count; i++)
put_page(ctxt->pages[i]);
- for (i = 0; i < ctxt->count; i++)
- ib_dma_unmap_single(xprt->sc_cm_id->device,
- ctxt->sge[i].addr,
- ctxt->sge[i].length,
- ctxt->direction);
-
spin_lock_bh(&xprt->sc_ctxt_lock);
list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
spin_unlock_bh(&xprt->sc_ctxt_lock);
@@ -328,6 +334,7 @@
ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
ctxt->wc_status = wc.status;
ctxt->byte_len = wc.byte_len;
+ svc_rdma_unmap_dma(ctxt);
if (wc.status != IB_WC_SUCCESS) {
/* Close the transport */
dprintk("svcrdma: transport closing putting ctxt %p\n", ctxt);
@@ -377,6 +384,7 @@
ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
xprt = ctxt->xprt;
+ svc_rdma_unmap_dma(ctxt);
if (wc.status != IB_WC_SUCCESS)
/* Close the transport */
set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);