| Message ID | 91e53f7b-fdb6-bd66-ada6-982c641c2048@sandisk.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On Tue, Jun 28, 2016 at 01:25:15PM +0200, Bart Van Assche wrote: > Some but not all callers of rdma_rw_ctx_init() zero-initialize > struct rdma_rw_ctx. Hence make rdma_rw_ctx_init() initialize all > work request fields that will be read by ib_post_send(). > > Fixes: b99f8e4d7bcd ("IB/srpt: convert to the generic RDMA READ/WRITE API") > Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> > Cc: <stable@vger.kernel.org> #v4.7+ > Cc: Christoph Hellwig <hch@lst.de> > Cc: Sagi Grimberg <sagi@grimberg.me> > Cc: Nicholas Bellinger <nab@linux-iscsi.org> > Cc: Parav Pandit <pandit.parav@gmail.com> > Cc: Laurence Oberman <loberman@redhat.com> > --- > drivers/infiniband/core/rw.c | 14 +++++++++----- > 1 file changed, 9 insertions(+), 5 deletions(-) > > diff --git a/drivers/infiniband/core/rw.c b/drivers/infiniband/core/rw.c > index 1eb9b12..13d4067 100644 > --- a/drivers/infiniband/core/rw.c > +++ b/drivers/infiniband/core/rw.c > @@ -99,6 +99,7 @@ static int rdma_rw_init_one_mr(struct ib_qp *qp, u8 port_num, > } > > reg->reg_wr.wr.opcode = IB_WR_REG_MR; > + reg->reg_wr.wr.next = NULL; This one is always set up by the callers of the function. > @@ -114,6 +115,7 @@ static int rdma_rw_init_mr_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, > u8 port_num, struct scatterlist *sg, u32 sg_cnt, u32 offset, > u64 remote_addr, u32 rkey, enum dma_data_direction dir) > { > + struct rdma_rw_reg_ctx *prev = NULL; > u32 pages_per_mr = rdma_rw_fr_page_list_len(qp->pd->device); > int i, j, ret = 0, count = 0; > > @@ -125,7 +127,6 @@ static int rdma_rw_init_mr_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, > } > > for (i = 0; i < ctx->nr_ops; i++) { > - struct rdma_rw_reg_ctx *prev = i ? &ctx->reg[i - 1] : NULL; > struct rdma_rw_reg_ctx *reg = &ctx->reg[i]; > u32 nents = min(sg_cnt, pages_per_mr); > > @@ -162,9 +163,13 @@ static int rdma_rw_init_mr_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, > sg_cnt -= nents; > for (j = 0; j < nents; j++) > sg = sg_next(sg); > + prev = reg; > offset = 0; > } > > + if (prev) > + prev->wr.wr.next = NULL; > + > ctx->type = RDMA_RW_MR; > return count; I think the right fix here is to set last_wr->next to NULL for the !chain_wr case in rdma_rw_ctx_wrs, or in fact maybe just simplify the end of rdma_rw_ctx_wrs to: last_wr->next = chain_wr; if (!chain_wr) { last_wr->wr_cqe = cqe; last_wr->send_flags |= IB_SEND_SIGNALED; } > @@ -205,11 +210,10 @@ static int rdma_rw_init_map_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, > rdma_wr->wr.opcode = IB_WR_RDMA_READ; > rdma_wr->remote_addr = remote_addr + total_len; > rdma_wr->rkey = rkey; > + rdma_wr->wr.num_sge = nr_sge; > rdma_wr->wr.sg_list = sge; > > for (j = 0; j < nr_sge; j++, sg = sg_next(sg)) { > - rdma_wr->wr.num_sge++; > - This parts looks fine. > - if (i + 1 < ctx->nr_ops) > - rdma_wr->wr.next = &ctx->map.wrs[i + 1].wr; > + rdma_wr->wr.next = i + 1 < ctx->nr_ops ? > + &ctx->map.wrs[i + 1].wr : NULL; I think the rdma_rw_ctx_wrs should take care of this as well. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 06/28/2016 01:51 PM, Christoph Hellwig wrote: > On Tue, Jun 28, 2016 at 01:25:15PM +0200, Bart Van Assche wrote: >> - if (i + 1 < ctx->nr_ops) >> - rdma_wr->wr.next = &ctx->map.wrs[i + 1].wr; >> + rdma_wr->wr.next = i + 1 < ctx->nr_ops ? >> + &ctx->map.wrs[i + 1].wr : NULL; > > I think the rdma_rw_ctx_wrs should take care of this as well. I agree that it is possible to let rdma_rw_ctx_wrs() initialize wr.next of the last WR. But if we chose that approach then drivers that call rdma_rw_ctx_init() but not rdma_rw_ctx_wrs(), e.g. ib_isert, can end up with a last wr.next field that has not been initialized. Hence my preference for performing that initialization in rdma_rw_init_mr_wrs() and rdma_rw_init_map_wrs(). Bart. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/infiniband/core/rw.c b/drivers/infiniband/core/rw.c index 1eb9b12..13d4067 100644 --- a/drivers/infiniband/core/rw.c +++ b/drivers/infiniband/core/rw.c @@ -99,6 +99,7 @@ static int rdma_rw_init_one_mr(struct ib_qp *qp, u8 port_num, } reg->reg_wr.wr.opcode = IB_WR_REG_MR; + reg->reg_wr.wr.next = NULL; reg->reg_wr.mr = reg->mr; reg->reg_wr.access = IB_ACCESS_LOCAL_WRITE; if (rdma_protocol_iwarp(qp->device, port_num)) @@ -114,6 +115,7 @@ static int rdma_rw_init_mr_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, u8 port_num, struct scatterlist *sg, u32 sg_cnt, u32 offset, u64 remote_addr, u32 rkey, enum dma_data_direction dir) { + struct rdma_rw_reg_ctx *prev = NULL; u32 pages_per_mr = rdma_rw_fr_page_list_len(qp->pd->device); int i, j, ret = 0, count = 0; @@ -125,7 +127,6 @@ static int rdma_rw_init_mr_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, } for (i = 0; i < ctx->nr_ops; i++) { - struct rdma_rw_reg_ctx *prev = i ? &ctx->reg[i - 1] : NULL; struct rdma_rw_reg_ctx *reg = &ctx->reg[i]; u32 nents = min(sg_cnt, pages_per_mr); @@ -162,9 +163,13 @@ static int rdma_rw_init_mr_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, sg_cnt -= nents; for (j = 0; j < nents; j++) sg = sg_next(sg); + prev = reg; offset = 0; } + if (prev) + prev->wr.wr.next = NULL; + ctx->type = RDMA_RW_MR; return count; @@ -205,11 +210,10 @@ static int rdma_rw_init_map_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, rdma_wr->wr.opcode = IB_WR_RDMA_READ; rdma_wr->remote_addr = remote_addr + total_len; rdma_wr->rkey = rkey; + rdma_wr->wr.num_sge = nr_sge; rdma_wr->wr.sg_list = sge; for (j = 0; j < nr_sge; j++, sg = sg_next(sg)) { - rdma_wr->wr.num_sge++; - sge->addr = ib_sg_dma_address(dev, sg) + offset; sge->length = ib_sg_dma_len(dev, sg) - offset; sge->lkey = qp->pd->local_dma_lkey; @@ -220,8 +224,8 @@ static int rdma_rw_init_map_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp, offset = 0; } - if (i + 1 < ctx->nr_ops) - rdma_wr->wr.next = &ctx->map.wrs[i + 1].wr; + rdma_wr->wr.next = i + 1 < ctx->nr_ops ? + &ctx->map.wrs[i + 1].wr : NULL; } ctx->type = RDMA_RW_MULTI_WR;
Some but not all callers of rdma_rw_ctx_init() zero-initialize struct rdma_rw_ctx. Hence make rdma_rw_ctx_init() initialize all work request fields that will be read by ib_post_send(). Fixes: b99f8e4d7bcd ("IB/srpt: convert to the generic RDMA READ/WRITE API") Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: <stable@vger.kernel.org> #v4.7+ Cc: Christoph Hellwig <hch@lst.de> Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Nicholas Bellinger <nab@linux-iscsi.org> Cc: Parav Pandit <pandit.parav@gmail.com> Cc: Laurence Oberman <loberman@redhat.com> --- drivers/infiniband/core/rw.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-)