xprtrdma: Remove ->ro_reset

An RPC can exit at any time. When it does so, xprt_rdma_free() is
called, and it calls ->op_unmap().

If ->ro_reset() is running due to a transport disconnect, the two
methods can race while processing the same rpcrdma_mw. The results
are unpredictable.

Because of this, in previous patches I've altered ->ro_map() to
handle MR reset. ->ro_reset() is no longer needed and can be
removed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Devesh Sharma <devesh.sharma@avagotech.com>
Tested-By: Devesh Sharma <devesh.sharma@avagotech.com>
Reviewed-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/net/sunrpc/xprtrdma/fmr_ops.c b/net/sunrpc/xprtrdma/fmr_ops.c
index 53fb649..5dd77da 100644 (file)
--- a/net/sunrpc/xprtrdma/fmr_ops.c
+++ b/net/sunrpc/xprtrdma/fmr_ops.c
@@ -197,28 +197,6 @@ out_err:
        return nsegs;
 }
 
-/* After a disconnect, unmap all FMRs.
- *
- * This is invoked only in the transport connect worker in order
- * to serialize with rpcrdma_register_fmr_external().
- */
-static void
-fmr_op_reset(struct rpcrdma_xprt *r_xprt)
-{
-       struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
-       struct rpcrdma_mw *r;
-       LIST_HEAD(list);
-       int rc;
-
-       list_for_each_entry(r, &buf->rb_all, mw_all)
-               list_add(&r->r.fmr->list, &list);
-
-       rc = ib_unmap_fmr(&list);
-       if (rc)
-               dprintk("RPC:       %s: ib_unmap_fmr failed %i\n",
-                       __func__, rc);
-}
-
 static void
 fmr_op_destroy(struct rpcrdma_buffer *buf)
 {
@@ -242,7 +220,6 @@ const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
        .ro_open                        = fmr_op_open,
        .ro_maxpages                    = fmr_op_maxpages,
        .ro_init                        = fmr_op_init,
-       .ro_reset                       = fmr_op_reset,
        .ro_destroy                     = fmr_op_destroy,
        .ro_displayname                 = "fmr",
 };

diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c
index 133edf6..8622792 100644 (file)
--- a/net/sunrpc/xprtrdma/frwr_ops.c
+++ b/net/sunrpc/xprtrdma/frwr_ops.c
@@ -430,44 +430,6 @@ out_err:
        return nsegs;
 }
 
-/* After a disconnect, a flushed FAST_REG_MR can leave an FRMR in
- * an unusable state. Find FRMRs in this state and dereg / reg
- * each.  FRMRs that are VALID and attached to an rpcrdma_req are
- * also torn down.
- *
- * This gives all in-use FRMRs a fresh rkey and leaves them INVALID.
- *
- * This is invoked only in the transport connect worker in order
- * to serialize with rpcrdma_register_frmr_external().
- */
-static void
-frwr_op_reset(struct rpcrdma_xprt *r_xprt)
-{
-       struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
-       struct ib_device *device = r_xprt->rx_ia.ri_device;
-       unsigned int depth = r_xprt->rx_ia.ri_max_frmr_depth;
-       struct ib_pd *pd = r_xprt->rx_ia.ri_pd;
-       struct rpcrdma_mw *r;
-       int rc;
-
-       list_for_each_entry(r, &buf->rb_all, mw_all) {
-               if (r->r.frmr.fr_state == FRMR_IS_INVALID)
-                       continue;
-
-               __frwr_release(r);
-               rc = __frwr_init(r, pd, device, depth);
-               if (rc) {
-                       dprintk("RPC:       %s: mw %p left %s\n",
-                               __func__, r,
-                               (r->r.frmr.fr_state == FRMR_IS_STALE ?
-                                       "stale" : "valid"));
-                       continue;
-               }
-
-               r->r.frmr.fr_state = FRMR_IS_INVALID;
-       }
-}
-
 static void
 frwr_op_destroy(struct rpcrdma_buffer *buf)
 {
@@ -490,7 +452,6 @@ const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops = {
        .ro_open                        = frwr_op_open,
        .ro_maxpages                    = frwr_op_maxpages,
        .ro_init                        = frwr_op_init,
-       .ro_reset                       = frwr_op_reset,
        .ro_destroy                     = frwr_op_destroy,
        .ro_displayname                 = "frwr",
 };

diff --git a/net/sunrpc/xprtrdma/physical_ops.c b/net/sunrpc/xprtrdma/physical_ops.c
index da149e8..41985d0 100644 (file)
--- a/net/sunrpc/xprtrdma/physical_ops.c
+++ b/net/sunrpc/xprtrdma/physical_ops.c
@@ -69,11 +69,6 @@ physical_op_unmap(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg)
 }
 
 static void
-physical_op_reset(struct rpcrdma_xprt *r_xprt)
-{
-}
-
-static void
 physical_op_destroy(struct rpcrdma_buffer *buf)
 {
 }
@@ -84,7 +79,6 @@ const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops = {
        .ro_open                        = physical_op_open,
        .ro_maxpages                    = physical_op_maxpages,
        .ro_init                        = physical_op_init,
-       .ro_reset                       = physical_op_reset,
        .ro_destroy                     = physical_op_destroy,
        .ro_displayname                 = "physical",
 };

diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index a891cf7..db9303a 100644 (file)
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -891,8 +891,6 @@ retry:
                rpcrdma_flush_cqs(ep);
 
                xprt = container_of(ia, struct rpcrdma_xprt, rx_ia);
-               ia->ri_ops->ro_reset(xprt);
-
                id = rpcrdma_create_id(xprt, ia,
                                (struct sockaddr *)&xprt->rx_data.addr);
                if (IS_ERR(id)) {

diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h
index c5862a4..f19376d 100644 (file)
--- a/net/sunrpc/xprtrdma/xprt_rdma.h
+++ b/net/sunrpc/xprtrdma/xprt_rdma.h
@@ -352,7 +352,6 @@ struct rpcrdma_memreg_ops {
                                   struct rpcrdma_create_data_internal *);
        size_t          (*ro_maxpages)(struct rpcrdma_xprt *);
        int             (*ro_init)(struct rpcrdma_xprt *);
-       void            (*ro_reset)(struct rpcrdma_xprt *);
        void            (*ro_destroy)(struct rpcrdma_buffer *);
        const char      *ro_displayname;
 };