diff options
| author | Chuck Lever <chuck.lever@oracle.com> | 2017-06-08 11:51:56 -0400 |
|---|---|---|
| committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2017-07-13 16:00:10 -0400 |
| commit | 4b196dc6fee9ba838ebabf824e294a429c79b27d (patch) | |
| tree | 075fb31c1d415171267a652574eea3b139c96253 /net/sunrpc/xprtrdma/rpc_rdma.c | |
| parent | 04d25b7d5d1b43fbaffe4ad4bb21288f0f305338 (diff) | |
xprtrdma: Pre-mark remotely invalidated MRs
There are rare cases where an rpcrdma_req and its matched
rpcrdma_rep can be re-used, via rpcrdma_buffer_put, while the RPC
reply handler is still using that req. This is typically due to a
signal firing at just the wrong instant.
As part of closing this race window, avoid using the wrong
rpcrdma_rep to detect remotely invalidated MRs. Mark MRs as
invalidated while we are sure the rep is still OK to use.
BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=305
Fixes: 68791649a725 ('xprtrdma: Invalidate in the RPC reply ... ')
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'net/sunrpc/xprtrdma/rpc_rdma.c')
| -rw-r--r-- | net/sunrpc/xprtrdma/rpc_rdma.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c index 694e9b13ecf0..2356a6305f25 100644 --- a/net/sunrpc/xprtrdma/rpc_rdma.c +++ b/net/sunrpc/xprtrdma/rpc_rdma.c @@ -928,6 +928,24 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad) return fixup_copy_count; } +/* Caller must guarantee @rep remains stable during this call. + */ +static void +rpcrdma_mark_remote_invalidation(struct list_head *mws, + struct rpcrdma_rep *rep) +{ + struct rpcrdma_mw *mw; + + if (!(rep->rr_wc_flags & IB_WC_WITH_INVALIDATE)) + return; + + list_for_each_entry(mw, mws, mw_list) + if (mw->mw_handle == rep->rr_inv_rkey) { + mw->mw_flags = RPCRDMA_MW_F_RI; + break; /* only one invalidated MR per RPC */ + } +} + #if defined(CONFIG_SUNRPC_BACKCHANNEL) /* By convention, backchannel calls arrive via rdma_msg type * messages, and never populate the chunk lists. This makes @@ -1006,13 +1024,13 @@ rpcrdma_reply_handler(struct work_struct *work) /* Sanity checking has passed. We are now committed * to complete this transaction. */ + rpcrdma_mark_remote_invalidation(&req->rl_registered, rep); list_del_init(&rqst->rq_list); + req->rl_reply = rep; spin_unlock_bh(&xprt->transport_lock); dprintk("RPC: %s: reply %p completes request %p (xid 0x%08x)\n", __func__, rep, req, be32_to_cpu(headerp->rm_xid)); - /* from here on, the reply is no longer an orphan */ - req->rl_reply = rep; xprt->reestablish_timeout = 0; if (headerp->rm_vers != rpcrdma_version) |