From: Chuck Lever <chuck.lever@oracle.com>
Date: Thu, 15 Sep 2016 14:55:45 +0000 (-0400)
Subject: SUNRPC: Add a transport-specific private field in rpc_rqst
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=5a6d1db45569;p=linux.git
SUNRPC: Add a transport-specific private field in rpc_rqst
Currently there's a hidden and indirect mechanism for finding the
rpcrdma_req that goes with an rpc_rqst. It depends on getting from
the rq_buffer pointer in struct rpc_rqst to the struct
rpcrdma_regbuf that controls that buffer, and then to the struct
rpcrdma_req it goes with.
This was done back in the day to avoid the need to add a per-rqst
pointer or to alter the buf_free API when support for RPC-over-RDMA
was introduced.
I'm about to change the way regbuf's work to support larger inline
thresholds. Now is a good time to replace this indirect mechanism
with something that is more straightforward. I guess this should be
considered a clean up.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 46f069efa0561..a5da60b24d83e 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -83,6 +83,7 @@ struct rpc_rqst {
void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
struct list_head rq_list;
+ void *rq_xprtdata; /* Per-xprt private data */
void *rq_buffer; /* Call XDR encode buffer */
size_t rq_callsize;
void *rq_rbuffer; /* Reply XDR decode buffer */
diff --git a/net/sunrpc/xprtrdma/backchannel.c b/net/sunrpc/xprtrdma/backchannel.c
index d3cfaf281e55d..c4904f8816401 100644
--- a/net/sunrpc/xprtrdma/backchannel.c
+++ b/net/sunrpc/xprtrdma/backchannel.c
@@ -55,11 +55,9 @@ static int rpcrdma_bc_setup_rqst(struct rpcrdma_xprt *r_xprt,
rb = rpcrdma_alloc_regbuf(ia, size, GFP_KERNEL);
if (IS_ERR(rb))
goto out_fail;
- rb->rg_owner = req;
req->rl_sendbuf = rb;
- /* so that rpcr_to_rdmar works when receiving a request */
- rqst->rq_buffer = (void *)req->rl_sendbuf->rg_base;
- xdr_buf_init(&rqst->rq_snd_buf, rqst->rq_buffer, size);
+ xdr_buf_init(&rqst->rq_snd_buf, rb->rg_base, size);
+ rpcrdma_set_xprtdata(rqst, req);
return 0;
out_fail:
diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c
index 136caf3dd299c..d83bffa92dfc4 100644
--- a/net/sunrpc/xprtrdma/transport.c
+++ b/net/sunrpc/xprtrdma/transport.c
@@ -523,6 +523,7 @@ xprt_rdma_allocate(struct rpc_task *task)
out:
dprintk("RPC: %s: size %zd, request 0x%p\n", __func__, size, req);
req->rl_connect_cookie = 0; /* our reserved value */
+ rpcrdma_set_xprtdata(rqst, req);
rqst->rq_buffer = req->rl_sendbuf->rg_base;
rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_rcvsize;
return 0;
@@ -559,7 +560,6 @@ out_sendbuf:
rb = rpcrdma_alloc_regbuf(&r_xprt->rx_ia, size, flags);
if (IS_ERR(rb))
goto out_fail;
- rb->rg_owner = req;
r_xprt->rx_stats.hardway_register_count += size;
rpcrdma_free_regbuf(&r_xprt->rx_ia, req->rl_sendbuf);
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 799cce6cbe45e..93def0bf07af6 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -1210,7 +1210,6 @@ rpcrdma_alloc_regbuf(struct rpcrdma_ia *ia, size_t size, gfp_t flags)
iov->length = size;
iov->lkey = ia->ri_pd->local_dma_lkey;
rb->rg_size = size;
- rb->rg_owner = NULL;
return rb;
out_free:
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h
index 4838a85bdcf6b..484855eddb85d 100644
--- a/net/sunrpc/xprtrdma/xprt_rdma.h
+++ b/net/sunrpc/xprtrdma/xprt_rdma.h
@@ -113,7 +113,6 @@ struct rpcrdma_ep {
struct rpcrdma_regbuf {
size_t rg_size;
- struct rpcrdma_req *rg_owner;
struct ib_sge rg_iov;
__be32 rg_base[0] __attribute__ ((aligned(256)));
};
@@ -297,14 +296,16 @@ struct rpcrdma_req {
struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];
};
+static inline void
+rpcrdma_set_xprtdata(struct rpc_rqst *rqst, struct rpcrdma_req *req)
+{
+ rqst->rq_xprtdata = req;
+}
+
static inline struct rpcrdma_req *
rpcr_to_rdmar(struct rpc_rqst *rqst)
{
- void *buffer = rqst->rq_buffer;
- struct rpcrdma_regbuf *rb;
-
- rb = container_of(buffer, struct rpcrdma_regbuf, rg_base);
- return rb->rg_owner;
+ return rqst->rq_xprtdata;
}
/*