From 394b2c77cb761fb1382b0e97b7cdff2dd717b5ee Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 20 Oct 2017 10:47:47 -0400 Subject: xprtrdma: Fix error handling in rpcrdma_prepare_msg_sges() When this function fails, it needs to undo the DMA mappings it's done so far. Otherwise these are leaked. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker --- net/sunrpc/xprtrdma/rpc_rdma.c | 38 ++++++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 14 deletions(-) (limited to 'net/sunrpc/xprtrdma') diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c index 3c9255824d94..4f6c5395d198 100644 --- a/net/sunrpc/xprtrdma/rpc_rdma.c +++ b/net/sunrpc/xprtrdma/rpc_rdma.c @@ -511,6 +511,28 @@ rpcrdma_encode_reply_chunk(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, return 0; } +/** + * rpcrdma_unmap_sges - DMA-unmap Send buffers + * @ia: interface adapter (device) + * @req: req with possibly some SGEs to be DMA unmapped + * + */ +void +rpcrdma_unmap_sges(struct rpcrdma_ia *ia, struct rpcrdma_req *req) +{ + struct ib_sge *sge; + unsigned int count; + + /* The first two SGEs contain the transport header and + * the inline buffer. These are always left mapped so + * they can be cheaply re-used. + */ + sge = &req->rl_send_sge[2]; + for (count = req->rl_mapped_sges; count--; sge++) + ib_dma_unmap_page(ia->ri_device, + sge->addr, sge->length, DMA_TO_DEVICE); +} + /* Prepare the RPC-over-RDMA header SGE. */ static bool @@ -641,10 +663,12 @@ out: return true; out_mapping_overflow: + rpcrdma_unmap_sges(ia, req); pr_err("rpcrdma: too many Send SGEs (%u)\n", sge_no); return false; out_mapping_err: + rpcrdma_unmap_sges(ia, req); pr_err("rpcrdma: Send mapping error\n"); return false; } @@ -671,20 +695,6 @@ out_map: return false; } -void -rpcrdma_unmap_sges(struct rpcrdma_ia *ia, struct rpcrdma_req *req) -{ - struct ib_device *device = ia->ri_device; - struct ib_sge *sge; - int count; - - sge = &req->rl_send_sge[2]; - for (count = req->rl_mapped_sges; count--; sge++) - ib_dma_unmap_page(device, sge->addr, sge->length, - DMA_TO_DEVICE); - req->rl_mapped_sges = 0; -} - /** * rpcrdma_marshal_req - Marshal and send one RPC request * @r_xprt: controlling transport -- cgit v1.2.3