svcrdma: Add FRMR get/put services
Add services for the allocating, freeing, and unmapping Fast Reg MR. These
services will be used by the transport connection setup, send and receive
routines.
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 900cb69..f0b5c5f 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -100,6 +100,7 @@
ctxt->xprt = xprt;
INIT_LIST_HEAD(&ctxt->dto_q);
ctxt->count = 0;
+ ctxt->frmr = NULL;
atomic_inc(&xprt->sc_ctxt_used);
return ctxt;
}
@@ -109,11 +110,19 @@
struct svcxprt_rdma *xprt = ctxt->xprt;
int i;
for (i = 0; i < ctxt->count && ctxt->sge[i].length; i++) {
- atomic_dec(&xprt->sc_dma_used);
- ib_dma_unmap_single(xprt->sc_cm_id->device,
- ctxt->sge[i].addr,
- ctxt->sge[i].length,
- ctxt->direction);
+ /*
+ * Unmap the DMA addr in the SGE if the lkey matches
+ * the sc_dma_lkey, otherwise, ignore it since it is
+ * an FRMR lkey and will be unmapped later when the
+ * last WR that uses it completes.
+ */
+ if (ctxt->sge[i].lkey == xprt->sc_dma_lkey) {
+ atomic_dec(&xprt->sc_dma_used);
+ ib_dma_unmap_single(xprt->sc_cm_id->device,
+ ctxt->sge[i].addr,
+ ctxt->sge[i].length,
+ ctxt->direction);
+ }
}
}
@@ -150,6 +159,7 @@
schedule_timeout_uninterruptible(msecs_to_jiffies(500));
}
map->count = 0;
+ map->frmr = NULL;
return map;
}
@@ -425,10 +435,12 @@
INIT_LIST_HEAD(&cma_xprt->sc_dto_q);
INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q);
INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q);
+ INIT_LIST_HEAD(&cma_xprt->sc_frmr_q);
init_waitqueue_head(&cma_xprt->sc_send_wait);
spin_lock_init(&cma_xprt->sc_lock);
spin_lock_init(&cma_xprt->sc_rq_dto_lock);
+ spin_lock_init(&cma_xprt->sc_frmr_q_lock);
cma_xprt->sc_ord = svcrdma_ord;
@@ -686,6 +698,97 @@
return ERR_PTR(ret);
}
+static struct svc_rdma_fastreg_mr *rdma_alloc_frmr(struct svcxprt_rdma *xprt)
+{
+ struct ib_mr *mr;
+ struct ib_fast_reg_page_list *pl;
+ struct svc_rdma_fastreg_mr *frmr;
+
+ frmr = kmalloc(sizeof(*frmr), GFP_KERNEL);
+ if (!frmr)
+ goto err;
+
+ mr = ib_alloc_fast_reg_mr(xprt->sc_pd, RPCSVC_MAXPAGES);
+ if (!mr)
+ goto err_free_frmr;
+
+ pl = ib_alloc_fast_reg_page_list(xprt->sc_cm_id->device,
+ RPCSVC_MAXPAGES);
+ if (!pl)
+ goto err_free_mr;
+
+ frmr->mr = mr;
+ frmr->page_list = pl;
+ INIT_LIST_HEAD(&frmr->frmr_list);
+ return frmr;
+
+ err_free_mr:
+ ib_dereg_mr(mr);
+ err_free_frmr:
+ kfree(frmr);
+ err:
+ return ERR_PTR(-ENOMEM);
+}
+
+static void rdma_dealloc_frmr_q(struct svcxprt_rdma *xprt)
+{
+ struct svc_rdma_fastreg_mr *frmr;
+
+ while (!list_empty(&xprt->sc_frmr_q)) {
+ frmr = list_entry(xprt->sc_frmr_q.next,
+ struct svc_rdma_fastreg_mr, frmr_list);
+ list_del_init(&frmr->frmr_list);
+ ib_dereg_mr(frmr->mr);
+ ib_free_fast_reg_page_list(frmr->page_list);
+ kfree(frmr);
+ }
+}
+
+struct svc_rdma_fastreg_mr *svc_rdma_get_frmr(struct svcxprt_rdma *rdma)
+{
+ struct svc_rdma_fastreg_mr *frmr = NULL;
+
+ spin_lock_bh(&rdma->sc_frmr_q_lock);
+ if (!list_empty(&rdma->sc_frmr_q)) {
+ frmr = list_entry(rdma->sc_frmr_q.next,
+ struct svc_rdma_fastreg_mr, frmr_list);
+ list_del_init(&frmr->frmr_list);
+ frmr->map_len = 0;
+ frmr->page_list_len = 0;
+ }
+ spin_unlock_bh(&rdma->sc_frmr_q_lock);
+ if (frmr)
+ return frmr;
+
+ return rdma_alloc_frmr(rdma);
+}
+
+static void frmr_unmap_dma(struct svcxprt_rdma *xprt,
+ struct svc_rdma_fastreg_mr *frmr)
+{
+ int page_no;
+ for (page_no = 0; page_no < frmr->page_list_len; page_no++) {
+ dma_addr_t addr = frmr->page_list->page_list[page_no];
+ if (ib_dma_mapping_error(frmr->mr->device, addr))
+ continue;
+ atomic_dec(&xprt->sc_dma_used);
+ ib_dma_unmap_single(frmr->mr->device, addr, PAGE_SIZE,
+ frmr->direction);
+ }
+}
+
+void svc_rdma_put_frmr(struct svcxprt_rdma *rdma,
+ struct svc_rdma_fastreg_mr *frmr)
+{
+ if (frmr) {
+ frmr_unmap_dma(rdma, frmr);
+ spin_lock_bh(&rdma->sc_frmr_q_lock);
+ BUG_ON(!list_empty(&frmr->frmr_list));
+ list_add(&frmr->frmr_list, &rdma->sc_frmr_q);
+ spin_unlock_bh(&rdma->sc_frmr_q_lock);
+ }
+}
+
/*
* This is the xpo_recvfrom function for listening endpoints. Its
* purpose is to accept incoming connections. The CMA callback handler
@@ -961,6 +1064,9 @@
WARN_ON(atomic_read(&rdma->sc_ctxt_used) != 0);
WARN_ON(atomic_read(&rdma->sc_dma_used) != 0);
+ /* De-allocate fastreg mr */
+ rdma_dealloc_frmr_q(rdma);
+
/* Destroy the QP if present (not a listener) */
if (rdma->sc_qp && !IS_ERR(rdma->sc_qp))
ib_destroy_qp(rdma->sc_qp);