From bebd031866caa404c522e91bb6fd0c69be04c707 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Tue, 11 Apr 2017 13:23:10 -0400 Subject: xprtrdma: Support unplugging an HCA from under an NFS mount The device driver for the underlying physical device associated with an RPC-over-RDMA transport can be removed while RPC-over-RDMA transports are still in use (ie, while NFS filesystems are still mounted and active). The IB core performs a connection event upcall to request that consumers free all RDMA resources associated with a transport. There may be pending RPCs when this occurs. Care must be taken to release associated resources without leaving references that can trigger a subsequent crash if a signal or soft timeout occurs. We rely on the caller of the transport's ->close method to ensure that the previous RPC task has invoked xprt_release but the transport remains write-locked. A DEVICE_REMOVE upcall forces a disconnect then sleeps. When ->close is invoked, it destroys the transport's H/W resources, then wakes the upcall, which completes and allows the core driver unload to continue. BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=266 Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker --- net/sunrpc/xprtrdma/xprt_rdma.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'net/sunrpc/xprtrdma/xprt_rdma.h') diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 9d58260533fc..1c5de1af195b 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -69,6 +69,7 @@ struct rpcrdma_ia { struct rdma_cm_id *ri_id; struct ib_pd *ri_pd; struct completion ri_done; + struct completion ri_remove_done; int ri_async_rc; unsigned int ri_max_segs; unsigned int ri_max_frmr_depth; @@ -78,10 +79,15 @@ struct rpcrdma_ia { bool ri_reminv_expected; bool ri_implicit_roundup; enum ib_mr_type ri_mrtype; + unsigned long ri_flags; struct ib_qp_attr ri_qp_attr; struct ib_qp_init_attr ri_qp_init_attr; }; +enum { + RPCRDMA_IAF_REMOVING = 0, +}; + /* * RDMA Endpoint -- one per transport instance */ @@ -511,6 +517,7 @@ extern unsigned int xprt_rdma_memreg_strategy; * Interface Adapter calls - xprtrdma/verbs.c */ int rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr); +void rpcrdma_ia_remove(struct rpcrdma_ia *ia); void rpcrdma_ia_close(struct rpcrdma_ia *); bool frwr_is_supported(struct rpcrdma_ia *); bool fmr_is_supported(struct rpcrdma_ia *); -- cgit v1.2.3-59-g8ed1b