[RDMA PATCH 06/16] i40iw: Add qp table lock around AE processing

Mustafa Ismail
2016-04-07T16:30:54Z

QP may be freed during Async Event processing.
Add a lock around QP table to prevent it.

Signed-off-by: Mustafa Ismail <mustafa.ismail-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Faisal Latif <faisal.latif-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
drivers/infiniband/hw/i40iw/i40iw.h | 1 +
drivers/infiniband/hw/i40iw/i40iw_hw.c | 7 +++++++
drivers/infiniband/hw/i40iw/i40iw_utils.c | 9 +++++++--
3 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/i40iw/i40iw.h b/drivers/infiniband/hw/i40iw/i40iw.h
index 8197676..bf3627f 100644
--- a/drivers/infiniband/hw/i40iw/i40iw.h
+++ b/drivers/infiniband/hw/i40iw/i40iw.h
@@ -254,6 +254,7 @@ struct i40iw_device {
u32 arp_table_size;
u32 next_arp_index;
spinlock_t resource_lock; /* hw resource access */
+ spinlock_t qptable_lock;
u32 vendor_id;
u32 vendor_part_id;
u32 of_device_registered;
diff --git a/drivers/infiniband/hw/i40iw/i40iw_hw.c b/drivers/infiniband/hw/i40iw/i40iw_hw.c
index 9fd3024..27cfdd8 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_hw.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_hw.c
@@ -106,6 +106,7 @@ u32 i40iw_initialize_hw_resources(struct i40iw_device *iwdev)
set_bit(2, iwdev->allocated_pds);

spin_lock_init(&iwdev->resource_lock);
+ spin_lock_init(&iwdev->qptable_lock);
mrdrvbits = 24 - get_count_order(iwdev->max_mr);
iwdev->mr_stagmask = ~(((1 << mrdrvbits) - 1) << (32 - mrdrvbits));
return 0;
@@ -301,11 +302,15 @@ void i40iw_process_aeq(struct i40iw_device *iwdev)
"%s ae_id = 0x%x bool qp=%d qp_id = %d\n",
__func__, info->ae_id, info->qp, info->qp_cq_id);
if (info->qp) {
+ spin_lock_irqsave(&iwdev->qptable_lock, flags);
iwqp = iwdev->qp_table[info->qp_cq_id];
if (!iwqp) {
+ spin_unlock_irqrestore(&iwdev->qptable_lock, flags);
i40iw_pr_err("qp_id %d is already freed\n", info->qp_cq_id);
continue;
}
+ i40iw_add_ref(&iwqp->ibqp);
+ spin_unlock_irqrestore(&iwdev->qptable_lock, flags);
qp = &iwqp->sc_qp;
spin_lock_irqsave(&iwqp->lock, flags);
iwqp->hw_tcp_state = info->tcp_state;
@@ -411,6 +416,8 @@ void i40iw_process_aeq(struct i40iw_device *iwdev)
i40iw_terminate_connection(qp, info);
break;
}
+ if (info->qp)
+ i40iw_rem_ref(&iwqp->ibqp);
} while (1);

if (aeqcnt)
diff --git a/drivers/infiniband/hw/i40iw/i40iw_utils.c b/drivers/infiniband/hw/i40iw/i40iw_utils.c
index 1ceec81..7ed998c 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_utils.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_utils.c
@@ -506,14 +506,19 @@ void i40iw_rem_ref(struct ib_qp *ibqp)
struct cqp_commands_info *cqp_info;
struct i40iw_device *iwdev;
u32 qp_num;
+ unsigned long flags;

iwqp = to_iwqp(ibqp);
- if (!atomic_dec_and_test(&iwqp->refcount))
+ iwdev = iwqp->iwdev;
+ spin_lock_irqsave(&iwdev->qptable_lock, flags);
+ if (!atomic_dec_and_test(&iwqp->refcount)) {
+ spin_unlock_irqrestore(&iwdev->qptable_lock, flags);
return;
+ }

- iwdev = iwqp->iwdev;
qp_num = iwqp->ibqp.qp_num;
iwdev->qp_table[qp_num] = NULL;
+ spin_unlock_irqrestore(&iwdev->qptable_lock, flags);
cqp_request = i40iw_get_cqp_request(&iwdev->cqp, false);
if (!cqp_request)
return;