IB/qib: Fix QP RCU sparse warnings

Commit af061a644a0e ("IB/qib: Use RCU for qpn lookup") introduced sparse
warnings.

This patch corrects those issues.

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

diff --git a/drivers/infiniband/hw/qib/qib_iba7322.c b/drivers/infiniband/hw/qib/qib_iba7322.c
index c881e744c091f712b8914ee7bff5bad7ad4b0d48..78e85503c5092eb120dea73f9cd89d1511f43b28 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_iba7322.c
+++ b/drivers/infiniband/hw/qib/qib_iba7322.c
@@ -1,5 +1,6 @@
 /*
- * Copyright (c) 2008, 2009, 2010 QLogic Corporation. All rights reserved.
+ * Copyright (c) 2012 Intel Corporation.  All rights reserved.
+ * Copyright (c) 2008 - 2012 QLogic Corporation. All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
@@ -49,6 +50,7 @@
 #include "qib_qsfp.h"
 
 #include "qib_mad.h"
+#include "qib_verbs.h"
 
 static void qib_setup_7322_setextled(struct qib_pportdata *, u32);
 static void qib_7322_handle_hwerrors(struct qib_devdata *, char *, size_t);
@@ -5151,15 +5153,11 @@ static void try_7322_ipg(struct qib_pportdata *ppd)
                goto retry;
 
        if (!ibp->smi_ah) {
-               struct ib_ah_attr attr;
                struct ib_ah *ah;
 
-               memset(&attr, 0, sizeof attr);
-               attr.dlid = be16_to_cpu(IB_LID_PERMISSIVE);
-               attr.port_num = ppd->port;
-               ah = ib_create_ah(ibp->qp0->ibqp.pd, &attr);
+               ah = qib_create_qp0_ah(ibp, be16_to_cpu(IB_LID_PERMISSIVE));
                if (IS_ERR(ah))
-                       ret = -EINVAL;
+                       ret = PTR_ERR(ah);
                else {
                        send_buf->ah = ah;
                        ibp->smi_ah = to_iah(ah);

diff --git a/drivers/infiniband/hw/qib/qib_mad.c b/drivers/infiniband/hw/qib/qib_mad.c
index 43390217a0260695bf80fe6a420d5e0b6a534871..6e20b58b90b6e4d5ace6d3ee4eee97a882866598 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_mad.c
+++ b/drivers/infiniband/hw/qib/qib_mad.c
@@ -1,6 +1,6 @@
 /*
- * Copyright (c) 2006, 2007, 2008, 2009, 2010 QLogic Corporation.
- * All rights reserved.
+ * Copyright (c) 2012 Intel Corporation.  All rights reserved.
+ * Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
  *
  * This software is available to you under a choice of one of two
@@ -90,14 +90,10 @@ static void qib_send_trap(struct qib_ibport *ibp, void *data, unsigned len)
        if (!ibp->sm_ah) {
                if (ibp->sm_lid != be16_to_cpu(IB_LID_PERMISSIVE)) {
                        struct ib_ah *ah;
-                       struct ib_ah_attr attr;
 
-                       memset(&attr, 0, sizeof attr);
-                       attr.dlid = ibp->sm_lid;
-                       attr.port_num = ppd_from_ibp(ibp)->port;
-                       ah = ib_create_ah(ibp->qp0->ibqp.pd, &attr);
+                       ah = qib_create_qp0_ah(ibp, ibp->sm_lid);
                        if (IS_ERR(ah))
-                               ret = -EINVAL;
+                               ret = PTR_ERR(ah);
                        else {
                                send_buf->ah = ah;
                                ibp->sm_ah = to_iah(ah);

diff --git a/drivers/infiniband/hw/qib/qib_qp.c b/drivers/infiniband/hw/qib/qib_qp.c
index 693041b076f00d5387a8b90a386a233893478d12..4850d03870c297667e65c96b50d5ccec50b5aa01 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_qp.c
+++ b/drivers/infiniband/hw/qib/qib_qp.c
@@ -1,6 +1,6 @@
 /*
- * Copyright (c) 2006, 2007, 2008, 2009, 2010 QLogic Corporation.
- * All rights reserved.
+ * Copyright (c) 2012 Intel Corporation.  All rights reserved.
+ * Copyright (c) 2006 - 2012 QLogic Corporation.  * All rights reserved.
  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
  *
  * This software is available to you under a choice of one of two
@@ -250,23 +250,33 @@ static void remove_qp(struct qib_ibdev *dev, struct qib_qp *qp)
 
        spin_lock_irqsave(&dev->qpt_lock, flags);
 
-       if (ibp->qp0 == qp) {
+       if (rcu_dereference_protected(ibp->qp0,
+                       lockdep_is_held(&dev->qpt_lock)) == qp) {
                atomic_dec(&qp->refcount);
                rcu_assign_pointer(ibp->qp0, NULL);
-       } else if (ibp->qp1 == qp) {
+       } else if (rcu_dereference_protected(ibp->qp1,
+                       lockdep_is_held(&dev->qpt_lock)) == qp) {
                atomic_dec(&qp->refcount);
                rcu_assign_pointer(ibp->qp1, NULL);
        } else {
-               struct qib_qp *q, **qpp;
+               struct qib_qp *q;
+               struct qib_qp __rcu **qpp;
 
                qpp = &dev->qp_table[n];
-               for (; (q = *qpp) != NULL; qpp = &q->next)
+               q = rcu_dereference_protected(*qpp,
+                       lockdep_is_held(&dev->qpt_lock));
+               for (; q; qpp = &q->next) {
                        if (q == qp) {
                                atomic_dec(&qp->refcount);
-                               rcu_assign_pointer(*qpp, qp->next);
-                               qp->next = NULL;
+                               *qpp = qp->next;
+                               rcu_assign_pointer(qp->next, NULL);
+                               q = rcu_dereference_protected(*qpp,
+                                       lockdep_is_held(&dev->qpt_lock));
                                break;
                        }
+                       q = rcu_dereference_protected(*qpp,
+                               lockdep_is_held(&dev->qpt_lock));
+               }
        }
 
        spin_unlock_irqrestore(&dev->qpt_lock, flags);
@@ -302,10 +312,12 @@ unsigned qib_free_all_qps(struct qib_devdata *dd)
 
        spin_lock_irqsave(&dev->qpt_lock, flags);
        for (n = 0; n < dev->qp_table_size; n++) {
-               qp = dev->qp_table[n];
+               qp = rcu_dereference_protected(dev->qp_table[n],
+                       lockdep_is_held(&dev->qpt_lock));
                rcu_assign_pointer(dev->qp_table[n], NULL);
 
-               for (; qp; qp = qp->next)
+               for (; qp; qp = rcu_dereference_protected(qp->next,
+                                       lockdep_is_held(&dev->qpt_lock)))
                        qp_inuse++;
        }
        spin_unlock_irqrestore(&dev->qpt_lock, flags);
@@ -337,7 +349,8 @@ struct qib_qp *qib_lookup_qpn(struct qib_ibport *ibp, u32 qpn)
                unsigned n = qpn_hash(dev, qpn);
 
                rcu_read_lock();
-               for (qp = dev->qp_table[n]; rcu_dereference(qp); qp = qp->next)
+               for (qp = rcu_dereference(dev->qp_table[n]); qp;
+                       qp = rcu_dereference(qp->next))
                        if (qp->ibqp.qp_num == qpn)
                                break;
        }

diff --git a/drivers/infiniband/hw/qib/qib_verbs.c b/drivers/infiniband/hw/qib/qib_verbs.c
index 59cdea345a82ae756e92b9875b6df2cb2962567c..03ace0650a8f675c8017f965165da6ee9cdc400b 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_verbs.c
+++ b/drivers/infiniband/hw/qib/qib_verbs.c
@@ -1,6 +1,6 @@
 /*
- * Copyright (c) 2006, 2007, 2008, 2009, 2010 QLogic Corporation.
- * All rights reserved.
+ * Copyright (c) 2012 Intel Corporation.  All rights reserved.
+ * Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
  *
  * This software is available to you under a choice of one of two
@@ -1845,6 +1845,23 @@ bail:
        return ret;
 }
 
+struct ib_ah *qib_create_qp0_ah(struct qib_ibport *ibp, u16 dlid)
+{
+       struct ib_ah_attr attr;
+       struct ib_ah *ah = ERR_PTR(-EINVAL);
+       struct qib_qp *qp0;
+
+       memset(&attr, 0, sizeof attr);
+       attr.dlid = dlid;
+       attr.port_num = ppd_from_ibp(ibp)->port;
+       rcu_read_lock();
+       qp0 = rcu_dereference(ibp->qp0);
+       if (qp0)
+               ah = ib_create_ah(qp0->ibqp.pd, &attr);
+       rcu_read_unlock();
+       return ah;
+}
+
 /**
  * qib_destroy_ah - destroy an address handle
  * @ibah: the AH to destroy
@@ -2060,7 +2077,7 @@ int qib_register_ib_device(struct qib_devdata *dd)
        spin_lock_init(&dev->lk_table.lock);
        dev->lk_table.max = 1 << ib_qib_lkey_table_size;
        lk_tab_size = dev->lk_table.max * sizeof(*dev->lk_table.table);
-       dev->lk_table.table = (struct qib_mregion **)
+       dev->lk_table.table = (struct qib_mregion __rcu **)
                __get_free_pages(GFP_KERNEL, get_order(lk_tab_size));
        if (dev->lk_table.table == NULL) {
                ret = -ENOMEM;

diff --git a/drivers/infiniband/hw/qib/qib_verbs.h b/drivers/infiniband/hw/qib/qib_verbs.h
index 1293133f28cb1a017a46db32ed41f4c5a9051f03..61fad05328ca27719afa958337e316c3700f435c 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_verbs.h
+++ b/drivers/infiniband/hw/qib/qib_verbs.h
@@ -1,6 +1,6 @@
 /*
- * Copyright (c) 2006, 2007, 2008, 2009, 2010 QLogic Corporation.
- * All rights reserved.
+ * Copyright (c) 2012 Intel Corporation.  All rights reserved.
+ * Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
  *
  * This software is available to you under a choice of one of two
@@ -420,7 +420,7 @@ struct qib_qp {
        /* read mostly fields above and below */
        struct ib_ah_attr remote_ah_attr;
        struct ib_ah_attr alt_ah_attr;
-       struct qib_qp *next;            /* link list for QPN hash table */
+       struct qib_qp __rcu *next;            /* link list for QPN hash table */
        struct qib_swqe *s_wq;  /* send work queue */
        struct qib_mmap_info *ip;
        struct qib_ib_header *s_hdr;     /* next packet header to send */
@@ -659,8 +659,8 @@ struct qib_opcode_stats {
 };
 
 struct qib_ibport {
-       struct qib_qp *qp0;
-       struct qib_qp *qp1;
+       struct qib_qp __rcu *qp0;
+       struct qib_qp __rcu *qp1;
        struct ib_mad_agent *send_agent;        /* agent for SMI (traps) */
        struct qib_ah *sm_ah;
        struct qib_ah *smi_ah;
@@ -743,7 +743,7 @@ struct qib_ibdev {
        struct list_head memwait;       /* list for wait kernel memory */
        struct list_head txreq_free;
        struct timer_list mem_timer;
-       struct qib_qp **qp_table;
+       struct qib_qp __rcu **qp_table;
        struct qib_pio_header *pio_hdrs;
        dma_addr_t pio_hdrs_phys;
        /* list of QPs waiting for RNR timer */
@@ -937,6 +937,8 @@ void qib_rc_rcv(struct qib_ctxtdata *rcd, struct qib_ib_header *hdr,
 
 int qib_check_ah(struct ib_device *ibdev, struct ib_ah_attr *ah_attr);
 
+struct ib_ah *qib_create_qp0_ah(struct qib_ibport *ibp, u16 dlid);
+
 void qib_rc_rnr_retry(unsigned long arg);
 
 void qib_rc_send_complete(struct qib_qp *qp, struct qib_ib_header *hdr);