From 630a6a913e3a48f4890f8b9d912cd8217af59f19 Mon Sep 17 00:00:00 2001 From: Bernard Metzler Date: Fri, 4 Oct 2019 14:53:56 +0200 Subject: [PATCH] RDMA/siw: Fix SQ/RQ drain logic [ Upstream commit cf049bb31f7101d9672eaf97ade4fdd5171ddf26 ] Storage ULPs (e.g. iSER & NVMeOF) use ib_drain_qp() to drain QP/CQ. Current SIW's own drain routines do not properly wait until all SQ/RQ elements are completed and reaped from the CQ. This may cause touch after free issues. New logic relies on generic __ib_drain_sq()/__ib_drain_rq() posting a final work request, which SIW immediately flushes to CQ. Fixes: 303ae1cdfdf7 ("rdma/siw: application interface") Link: https://lore.kernel.org/r/20191004125356.20673-1-bmt@zurich.ibm.com Signed-off-by: Krishnamraju Eraparaju Signed-off-by: Bernard Metzler Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/sw/siw/siw_main.c | 20 ---- drivers/infiniband/sw/siw/siw_verbs.c | 144 ++++++++++++++++++++++---- 2 files changed, 122 insertions(+), 42 deletions(-) diff --git a/drivers/infiniband/sw/siw/siw_main.c b/drivers/infiniband/sw/siw/siw_main.c index 05a92f997f60..fb01407a310f 100644 --- a/drivers/infiniband/sw/siw/siw_main.c +++ b/drivers/infiniband/sw/siw/siw_main.c @@ -248,24 +248,6 @@ static struct ib_qp *siw_get_base_qp(struct ib_device *base_dev, int id) return NULL; } -static void siw_verbs_sq_flush(struct ib_qp *base_qp) -{ - struct siw_qp *qp = to_siw_qp(base_qp); - - down_write(&qp->state_lock); - siw_sq_flush(qp); - up_write(&qp->state_lock); -} - -static void siw_verbs_rq_flush(struct ib_qp *base_qp) -{ - struct siw_qp *qp = to_siw_qp(base_qp); - - down_write(&qp->state_lock); - siw_rq_flush(qp); - up_write(&qp->state_lock); -} - static const struct ib_device_ops siw_device_ops = { .owner = THIS_MODULE, .uverbs_abi_ver = SIW_ABI_VERSION, @@ -284,8 +266,6 @@ static const struct ib_device_ops siw_device_ops = { .destroy_cq = siw_destroy_cq, .destroy_qp = siw_destroy_qp, .destroy_srq = siw_destroy_srq, - .drain_rq = siw_verbs_rq_flush, - .drain_sq = siw_verbs_sq_flush, .get_dma_mr = siw_get_dma_mr, .get_port_immutable = siw_get_port_immutable, .iw_accept = siw_accept, diff --git a/drivers/infiniband/sw/siw/siw_verbs.c b/drivers/infiniband/sw/siw/siw_verbs.c index b18a677832e1..7d0a7edc533d 100644 --- a/drivers/infiniband/sw/siw/siw_verbs.c +++ b/drivers/infiniband/sw/siw/siw_verbs.c @@ -685,6 +685,47 @@ static int siw_copy_inline_sgl(const struct ib_send_wr *core_wr, return bytes; } +/* Complete SQ WR's without processing */ +static int siw_sq_flush_wr(struct siw_qp *qp, const struct ib_send_wr *wr, + const struct ib_send_wr **bad_wr) +{ + struct siw_sqe sqe = {}; + int rv = 0; + + while (wr) { + sqe.id = wr->wr_id; + sqe.opcode = wr->opcode; + rv = siw_sqe_complete(qp, &sqe, 0, SIW_WC_WR_FLUSH_ERR); + if (rv) { + if (bad_wr) + *bad_wr = wr; + break; + } + wr = wr->next; + } + return rv; +} + +/* Complete RQ WR's without processing */ +static int siw_rq_flush_wr(struct siw_qp *qp, const struct ib_recv_wr *wr, + const struct ib_recv_wr **bad_wr) +{ + struct siw_rqe rqe = {}; + int rv = 0; + + while (wr) { + rqe.id = wr->wr_id; + rv = siw_rqe_complete(qp, &rqe, 0, 0, SIW_WC_WR_FLUSH_ERR); + if (rv) { + if (bad_wr) + *bad_wr = wr; + break; + } + wr = wr->next; + } + return rv; +} + /* * siw_post_send() * @@ -703,26 +744,54 @@ int siw_post_send(struct ib_qp *base_qp, const struct ib_send_wr *wr, unsigned long flags; int rv = 0; + if (wr && !qp->kernel_verbs) { + siw_dbg_qp(qp, "wr must be empty for user mapped sq\n"); + *bad_wr = wr; + return -EINVAL; + } + /* * Try to acquire QP state lock. Must be non-blocking * to accommodate kernel clients needs. */ if (!down_read_trylock(&qp->state_lock)) { - *bad_wr = wr; - siw_dbg_qp(qp, "QP locked, state %d\n", qp->attrs.state); - return -ENOTCONN; + if (qp->attrs.state == SIW_QP_STATE_ERROR) { + /* + * ERROR state is final, so we can be sure + * this state will not change as long as the QP + * exists. + * + * This handles an ib_drain_sq() call with + * a concurrent request to set the QP state + * to ERROR. + */ + rv = siw_sq_flush_wr(qp, wr, bad_wr); + } else { + siw_dbg_qp(qp, "QP locked, state %d\n", + qp->attrs.state); + *bad_wr = wr; + rv = -ENOTCONN; + } + return rv; } if (unlikely(qp->attrs.state != SIW_QP_STATE_RTS)) { + if (qp->attrs.state == SIW_QP_STATE_ERROR) { + /* + * Immediately flush this WR to CQ, if QP + * is in ERROR state. SQ is guaranteed to + * be empty, so WR complets in-order. + * + * Typically triggered by ib_drain_sq(). + */ + rv = siw_sq_flush_wr(qp, wr, bad_wr); + } else { + siw_dbg_qp(qp, "QP out of state %d\n", + qp->attrs.state); + *bad_wr = wr; + rv = -ENOTCONN; + } up_read(&qp->state_lock); - *bad_wr = wr; - siw_dbg_qp(qp, "QP out of state %d\n", qp->attrs.state); - return -ENOTCONN; - } - if (wr && !qp->kernel_verbs) { - siw_dbg_qp(qp, "wr must be empty for user mapped sq\n"); - up_read(&qp->state_lock); - *bad_wr = wr; - return -EINVAL; + return rv; } spin_lock_irqsave(&qp->sq_lock, flags); @@ -917,24 +986,55 @@ int siw_post_receive(struct ib_qp *base_qp, const struct ib_recv_wr *wr, *bad_wr = wr; return -EOPNOTSUPP; /* what else from errno.h? */ } - /* - * Try to acquire QP state lock. Must be non-blocking - * to accommodate kernel clients needs. - */ - if (!down_read_trylock(&qp->state_lock)) { - *bad_wr = wr; - return -ENOTCONN; - } if (!qp->kernel_verbs) { siw_dbg_qp(qp, "no kernel post_recv for user mapped sq\n"); up_read(&qp->state_lock); *bad_wr = wr; return -EINVAL; } + + /* + * Try to acquire QP state lock. Must be non-blocking + * to accommodate kernel clients needs. + */ + if (!down_read_trylock(&qp->state_lock)) { + if (qp->attrs.state == SIW_QP_STATE_ERROR) { + /* + * ERROR state is final, so we can be sure + * this state will not change as long as the QP + * exists. + * + * This handles an ib_drain_rq() call with + * a concurrent request to set the QP state + * to ERROR. + */ + rv = siw_rq_flush_wr(qp, wr, bad_wr); + } else { + siw_dbg_qp(qp, "QP locked, state %d\n", + qp->attrs.state); + *bad_wr = wr; + rv = -ENOTCONN; + } + return rv; + } if (qp->attrs.state > SIW_QP_STATE_RTS) { + if (qp->attrs.state == SIW_QP_STATE_ERROR) { + /* + * Immediately flush this WR to CQ, if QP + * is in ERROR state. RQ is guaranteed to + * be empty, so WR complets in-order. + * + * Typically triggered by ib_drain_rq(). + */ + rv = siw_rq_flush_wr(qp, wr, bad_wr); + } else { + siw_dbg_qp(qp, "QP out of state %d\n", + qp->attrs.state); + *bad_wr = wr; + rv = -ENOTCONN; + } up_read(&qp->state_lock); - *bad_wr = wr; - return -EINVAL; + return rv; } /* * Serialize potentially multiple producers.