diff options
Diffstat (limited to 'net/sunrpc/xprtrdma/fmr_ops.c')
-rw-r--r-- | net/sunrpc/xprtrdma/fmr_ops.c | 52 |
1 files changed, 48 insertions, 4 deletions
diff --git a/net/sunrpc/xprtrdma/fmr_ops.c b/net/sunrpc/xprtrdma/fmr_ops.c index 0a96155bb03a..53fb649071d9 100644 --- a/net/sunrpc/xprtrdma/fmr_ops.c +++ b/net/sunrpc/xprtrdma/fmr_ops.c @@ -11,6 +11,21 @@ * can take tens of usecs to complete. */ +/* Normal operation + * + * A Memory Region is prepared for RDMA READ or WRITE using the + * ib_map_phys_fmr verb (fmr_op_map). When the RDMA operation is + * finished, the Memory Region is unmapped using the ib_unmap_fmr + * verb (fmr_op_unmap). + */ + +/* Transport recovery + * + * After a transport reconnect, fmr_op_map re-uses the MR already + * allocated for the RPC, but generates a fresh rkey then maps the + * MR again. This process is synchronous. + */ + #include "xprt_rdma.h" #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) @@ -77,6 +92,15 @@ out_fmr_err: return rc; } +static int +__fmr_unmap(struct rpcrdma_mw *r) +{ + LIST_HEAD(l); + + list_add(&r->r.fmr->list, &l); + return ib_unmap_fmr(&l); +} + /* Use the ib_map_phys_fmr() verb to register a memory region * for remote access via RDMA READ or RDMA WRITE. */ @@ -88,9 +112,22 @@ fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, struct ib_device *device = ia->ri_device; enum dma_data_direction direction = rpcrdma_data_dir(writing); struct rpcrdma_mr_seg *seg1 = seg; - struct rpcrdma_mw *mw = seg1->rl_mw; u64 physaddrs[RPCRDMA_MAX_DATA_SEGS]; int len, pageoff, i, rc; + struct rpcrdma_mw *mw; + + mw = seg1->rl_mw; + seg1->rl_mw = NULL; + if (!mw) { + mw = rpcrdma_get_mw(r_xprt); + if (!mw) + return -ENOMEM; + } else { + /* this is a retransmit; generate a fresh rkey */ + rc = __fmr_unmap(mw); + if (rc) + return rc; + } pageoff = offset_in_page(seg1->mr_offset); seg1->mr_offset -= pageoff; /* start of page */ @@ -114,6 +151,7 @@ fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, if (rc) goto out_maperr; + seg1->rl_mw = mw; seg1->mr_rkey = mw->r.fmr->rkey; seg1->mr_base = seg1->mr_dma + pageoff; seg1->mr_nsegs = i; @@ -137,18 +175,24 @@ fmr_op_unmap(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg) { struct rpcrdma_ia *ia = &r_xprt->rx_ia; struct rpcrdma_mr_seg *seg1 = seg; + struct rpcrdma_mw *mw = seg1->rl_mw; int rc, nsegs = seg->mr_nsegs; - LIST_HEAD(l); - list_add(&seg1->rl_mw->r.fmr->list, &l); - rc = ib_unmap_fmr(&l); + dprintk("RPC: %s: FMR %p\n", __func__, mw); + + seg1->rl_mw = NULL; while (seg1->mr_nsegs--) rpcrdma_unmap_one(ia->ri_device, seg++); + rc = __fmr_unmap(mw); if (rc) goto out_err; + rpcrdma_put_mw(r_xprt, mw); return nsegs; out_err: + /* The FMR is abandoned, but remains in rb_all. fmr_op_destroy + * will attempt to release it when the transport is destroyed. + */ dprintk("RPC: %s: ib_unmap_fmr status %i\n", __func__, rc); return nsegs; } |