IB/qib: Remove s_lock around header validation

Review of qib_ruc_check_hdr() shows that the s_lock is not required in
the normal case.  The r_lock is held in all cases, and protects the qp
fields that are read.

The s_lock will be needed to around the call to qib_migrate_qp() to
insure that the send engine sees a consistent set of fields.

Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/hw/qib/qib_driver.c b/drivers/infiniband/hw/qib/qib_driver.c
index d35c9d38ceee46186a34a1608780ec6d9bc6ea68..9a9047f385ae55b059339874fbf74fe8755911ce 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_driver.c
+++ b/drivers/infiniband/hw/qib/qib_driver.c
@@ -310,7 +310,6 @@ static u32 qib_rcv_hdrerr(struct qib_ctxtdata *rcd, struct qib_pportdata *ppd,
                u32 opcode;
                u32 psn;
                int diff;
-               unsigned long flags;
 
                /* Sanity check packet */
                if (tlen < 24)
@@ -365,7 +364,6 @@ static u32 qib_rcv_hdrerr(struct qib_ctxtdata *rcd, struct qib_pportdata *ppd,
 
                        switch (qp->ibqp.qp_type) {
                        case IB_QPT_RC:
-                               spin_lock_irqsave(&qp->s_lock, flags);
                                ruc_res =
                                        qib_ruc_check_hdr(
                                                ibp, hdr,
@@ -373,11 +371,8 @@ static u32 qib_rcv_hdrerr(struct qib_ctxtdata *rcd, struct qib_pportdata *ppd,
                                                qp,
                                                be32_to_cpu(ohdr->bth[0]));
                                if (ruc_res) {
-                                       spin_unlock_irqrestore(&qp->s_lock,
-                                                              flags);
                                        goto unlock;
                                }
-                               spin_unlock_irqrestore(&qp->s_lock, flags);
 
                                /* Only deal with RDMA Writes for now */
                                if (opcode <

diff --git a/drivers/infiniband/hw/qib/qib_rc.c b/drivers/infiniband/hw/qib/qib_rc.c
index ecfa087ad45eeb161342c4c448db22373fee8aba..afaf4ac79f42d78a640501d0d0912dc6ec3e2ae0 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_rc.c
+++ b/drivers/infiniband/hw/qib/qib_rc.c
@@ -1889,10 +1889,8 @@ void qib_rc_rcv(struct qib_ctxtdata *rcd, struct qib_ib_header *hdr,
        }
 
        opcode = be32_to_cpu(ohdr->bth[0]);
-       spin_lock_irqsave(&qp->s_lock, flags);
        if (qib_ruc_check_hdr(ibp, hdr, has_grh, qp, opcode))
-               goto sunlock;
-       spin_unlock_irqrestore(&qp->s_lock, flags);
+               return;
 
        psn = be32_to_cpu(ohdr->bth[2]);
        opcode >>= 24;

diff --git a/drivers/infiniband/hw/qib/qib_ruc.c b/drivers/infiniband/hw/qib/qib_ruc.c
index eb78d9367f06a6e358c7f3d504ed443bf6783983..b4b37e47321a9a27cb9b6afd2c1b0637c82b1c45 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_ruc.c
+++ b/drivers/infiniband/hw/qib/qib_ruc.c
@@ -260,12 +260,15 @@ static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
 
 /*
  *
- * This should be called with the QP s_lock held.
+ * This should be called with the QP r_lock held.
+ *
+ * The s_lock will be acquired around the qib_migrate_qp() call.
  */
 int qib_ruc_check_hdr(struct qib_ibport *ibp, struct qib_ib_header *hdr,
                      int has_grh, struct qib_qp *qp, u32 bth0)
 {
        __be64 guid;
+       unsigned long flags;
 
        if (qp->s_mig_state == IB_MIG_ARMED && (bth0 & IB_BTH_MIG_REQ)) {
                if (!has_grh) {
@@ -295,7 +298,9 @@ int qib_ruc_check_hdr(struct qib_ibport *ibp, struct qib_ib_header *hdr,
                if (be16_to_cpu(hdr->lrh[3]) != qp->alt_ah_attr.dlid ||
                    ppd_from_ibp(ibp)->port != qp->alt_ah_attr.port_num)
                        goto err;
+               spin_lock_irqsave(&qp->s_lock, flags);
                qib_migrate_qp(qp);
+               spin_unlock_irqrestore(&qp->s_lock, flags);
        } else {
                if (!has_grh) {
                        if (qp->remote_ah_attr.ah_flags & IB_AH_GRH)

diff --git a/drivers/infiniband/hw/qib/qib_uc.c b/drivers/infiniband/hw/qib/qib_uc.c
index 9a4630f8276f4a1331384b3b673e90634d299f38..847e7afdfd946ddc92697cac49713a0d21e9fca7 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_uc.c
+++ b/drivers/infiniband/hw/qib/qib_uc.c
@@ -243,7 +243,6 @@ void qib_uc_rcv(struct qib_ibport *ibp, struct qib_ib_header *hdr,
                int has_grh, void *data, u32 tlen, struct qib_qp *qp)
 {
        struct qib_other_headers *ohdr;
-       unsigned long flags;
        u32 opcode;
        u32 hdrsize;
        u32 psn;
@@ -263,10 +262,8 @@ void qib_uc_rcv(struct qib_ibport *ibp, struct qib_ib_header *hdr,
        }
 
        opcode = be32_to_cpu(ohdr->bth[0]);
-       spin_lock_irqsave(&qp->s_lock, flags);
        if (qib_ruc_check_hdr(ibp, hdr, has_grh, qp, opcode))
-               goto sunlock;
-       spin_unlock_irqrestore(&qp->s_lock, flags);
+               return;
 
        psn = be32_to_cpu(ohdr->bth[2]);
        opcode >>= 24;
@@ -554,6 +551,4 @@ op_err:
        qib_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
        return;
 
-sunlock:
-       spin_unlock_irqrestore(&qp->s_lock, flags);
 }