From c9918ff56dfb175ce427140c641280d0b4522dbe Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 16 Dec 2015 17:22:47 -0500 Subject: [PATCH] xprtrdma: Add ro_unmap_sync method for FRWR FRWR's ro_unmap is asynchronous. The new ro_unmap_sync posts LOCAL_INV Work Requests and waits for them to complete before returning. Note also, DMA unmapping is now done _after_ invalidation. Signed-off-by: Chuck Lever Tested-by: Devesh Sharma Signed-off-by: Anna Schumaker --- net/sunrpc/xprtrdma/frwr_ops.c | 136 +++++++++++++++++++++++++++++++- net/sunrpc/xprtrdma/xprt_rdma.h | 2 + 2 files changed, 134 insertions(+), 4 deletions(-) diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c index 31a45786137b..c6836844bd0e 100644 --- a/net/sunrpc/xprtrdma/frwr_ops.c +++ b/net/sunrpc/xprtrdma/frwr_ops.c @@ -245,12 +245,14 @@ frwr_op_maxpages(struct rpcrdma_xprt *r_xprt) rpcrdma_max_segments(r_xprt) * ia->ri_max_frmr_depth); } -/* If FAST_REG or LOCAL_INV failed, indicate the frmr needs to be reset. */ +/* If FAST_REG or LOCAL_INV failed, indicate the frmr needs + * to be reset. + * + * WARNING: Only wr_id and status are reliable at this point + */ static void -frwr_sendcompletion(struct ib_wc *wc) +__frwr_sendcompletion_flush(struct ib_wc *wc, struct rpcrdma_mw *r) { - struct rpcrdma_mw *r; - if (likely(wc->status == IB_WC_SUCCESS)) return; @@ -261,9 +263,23 @@ frwr_sendcompletion(struct ib_wc *wc) else pr_warn("RPC: %s: frmr %p error, status %s (%d)\n", __func__, r, ib_wc_status_msg(wc->status), wc->status); + r->r.frmr.fr_state = FRMR_IS_STALE; } +static void +frwr_sendcompletion(struct ib_wc *wc) +{ + struct rpcrdma_mw *r = (struct rpcrdma_mw *)(unsigned long)wc->wr_id; + struct rpcrdma_frmr *f = &r->r.frmr; + + if (unlikely(wc->status != IB_WC_SUCCESS)) + __frwr_sendcompletion_flush(wc, r); + + if (f->fr_waiter) + complete(&f->fr_linv_done); +} + static int frwr_op_init(struct rpcrdma_xprt *r_xprt) { @@ -335,6 +351,7 @@ frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, } while (mw->r.frmr.fr_state != FRMR_IS_INVALID); frmr = &mw->r.frmr; frmr->fr_state = FRMR_IS_VALID; + frmr->fr_waiter = false; mr = frmr->fr_mr; reg_wr = &frmr->fr_regwr; @@ -414,6 +431,116 @@ out_senderr: return rc; } +static struct ib_send_wr * +__frwr_prepare_linv_wr(struct rpcrdma_mr_seg *seg) +{ + struct rpcrdma_mw *mw = seg->rl_mw; + struct rpcrdma_frmr *f = &mw->r.frmr; + struct ib_send_wr *invalidate_wr; + + f->fr_waiter = false; + f->fr_state = FRMR_IS_INVALID; + invalidate_wr = &f->fr_invwr; + + memset(invalidate_wr, 0, sizeof(*invalidate_wr)); + invalidate_wr->wr_id = (unsigned long)(void *)mw; + invalidate_wr->opcode = IB_WR_LOCAL_INV; + invalidate_wr->ex.invalidate_rkey = f->fr_mr->rkey; + + return invalidate_wr; +} + +static void +__frwr_dma_unmap(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, + int rc) +{ + struct ib_device *device = r_xprt->rx_ia.ri_device; + struct rpcrdma_mw *mw = seg->rl_mw; + struct rpcrdma_frmr *f = &mw->r.frmr; + + seg->rl_mw = NULL; + + ib_dma_unmap_sg(device, f->sg, f->sg_nents, seg->mr_dir); + + if (!rc) + rpcrdma_put_mw(r_xprt, mw); + else + __frwr_queue_recovery(mw); +} + +/* Invalidate all memory regions that were registered for "req". + * + * Sleeps until it is safe for the host CPU to access the + * previously mapped memory regions. + */ +static void +frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req) +{ + struct ib_send_wr *invalidate_wrs, *pos, *prev, *bad_wr; + struct rpcrdma_ia *ia = &r_xprt->rx_ia; + struct rpcrdma_mr_seg *seg; + unsigned int i, nchunks; + struct rpcrdma_frmr *f; + int rc; + + dprintk("RPC: %s: req %p\n", __func__, req); + + /* ORDER: Invalidate all of the req's MRs first + * + * Chain the LOCAL_INV Work Requests and post them with + * a single ib_post_send() call. + */ + invalidate_wrs = pos = prev = NULL; + seg = NULL; + for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) { + seg = &req->rl_segments[i]; + + pos = __frwr_prepare_linv_wr(seg); + + if (!invalidate_wrs) + invalidate_wrs = pos; + else + prev->next = pos; + prev = pos; + + i += seg->mr_nsegs; + } + f = &seg->rl_mw->r.frmr; + + /* Strong send queue ordering guarantees that when the + * last WR in the chain completes, all WRs in the chain + * are complete. + */ + f->fr_invwr.send_flags = IB_SEND_SIGNALED; + f->fr_waiter = true; + init_completion(&f->fr_linv_done); + INIT_CQCOUNT(&r_xprt->rx_ep); + + /* Transport disconnect drains the receive CQ before it + * replaces the QP. The RPC reply handler won't call us + * unless ri_id->qp is a valid pointer. + */ + rc = ib_post_send(ia->ri_id->qp, invalidate_wrs, &bad_wr); + if (rc) + pr_warn("%s: ib_post_send failed %i\n", __func__, rc); + + wait_for_completion(&f->fr_linv_done); + + /* ORDER: Now DMA unmap all of the req's MRs, and return + * them to the free MW list. + */ + for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) { + seg = &req->rl_segments[i]; + + __frwr_dma_unmap(r_xprt, seg, rc); + + i += seg->mr_nsegs; + seg->mr_nsegs = 0; + } + + req->rl_nchunks = 0; +} + /* Post a LOCAL_INV Work Request to prevent further remote access * via RDMA READ or RDMA WRITE. */ @@ -473,6 +600,7 @@ frwr_op_destroy(struct rpcrdma_buffer *buf) const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops = { .ro_map = frwr_op_map, + .ro_unmap_sync = frwr_op_unmap_sync, .ro_unmap = frwr_op_unmap, .ro_open = frwr_op_open, .ro_maxpages = frwr_op_maxpages, diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index c32cba3f21fb..ddae4909982b 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -207,6 +207,8 @@ struct rpcrdma_frmr { enum rpcrdma_frmr_state fr_state; struct work_struct fr_work; struct rpcrdma_xprt *fr_xprt; + bool fr_waiter; + struct completion fr_linv_done;; union { struct ib_reg_wr fr_regwr; struct ib_send_wr fr_invwr; -- 2.20.1