[PATCH 3.19 119/177] IB/iser: Fix memory regions possible leak

Greg Kroah-Hartman
2015-03-16T15:39:10Z

From: Sagi Grimberg <sagig@mellanox.com>

commit 6606e6a2ff2710b473838b291dc533cd8fc1471f upstream.

When teardown process starts during live IO, we need to keep the
memory regions pool (frmr/fmr) until all in-flight tasks are properly
released, since each task may return a memory region to the pool. In
order to do this, we pass a destroy flag to iser_free_ib_conn_res to
indicate we can destroy the device and the memory regions
pool. iser_conn_release will pass it as true and also DEVICE_REMOVAL
event (we need to let the device to properly remove).

Also, Since we conditionally call iser_free_rx_descriptors,
remove the extra check on iser_conn->rx_descs.

Fixes: 5426b1711fd0 ("IB/iser: Collapse cleanup and disconnect handlers")
Reported-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/infiniband/ulp/iser/iser_initiator.c | 4 ----
drivers/infiniband/ulp/iser/iser_verbs.c | 25 ++++++++++++++-----------
2 files changed, 14 insertions(+), 15 deletions(-)

--- a/drivers/infiniband/ulp/iser/iser_initiator.c
+++ b/drivers/infiniband/ulp/iser/iser_initiator.c
@@ -320,9 +320,6 @@ void iser_free_rx_descriptors(struct ise
struct ib_conn *ib_conn = &iser_conn->ib_conn;
struct iser_device *device = ib_conn->device;

- if (!iser_conn->rx_descs)
- goto free_login_buf;
-
if (device->iser_free_rdma_reg_res)
device->iser_free_rdma_reg_res(ib_conn);

@@ -334,7 +331,6 @@ void iser_free_rx_descriptors(struct ise
/* make sure we never redo any unmapping */
iser_conn->rx_descs = NULL;

-free_login_buf:
iser_free_login_buf(iser_conn);
}

--- a/drivers/infiniband/ulp/iser/iser_verbs.c
+++ b/drivers/infiniband/ulp/iser/iser_verbs.c
@@ -600,16 +600,16 @@ void iser_release_work(struct work_struc
/**
* iser_free_ib_conn_res - release IB related resources
* @iser_conn: iser connection struct
- * @destroy_device: indicator if we need to try to release
- * the iser device (only iscsi shutdown and DEVICE_REMOVAL
- * will use this.
+ * @destroy: indicator if we need to try to release the
+ * iser device and memory regoins pool (only iscsi
+ * shutdown and DEVICE_REMOVAL will use this).
*
* This routine is called with the iser state mutex held
* so the cm_id removal is out of here. It is Safe to
* be invoked multiple times.
*/
static void iser_free_ib_conn_res(struct iser_conn *iser_conn,
- bool destroy_device)
+ bool destroy)
{
struct ib_conn *ib_conn = &iser_conn->ib_conn;
struct iser_device *device = ib_conn->device;
@@ -617,17 +617,20 @@ static void iser_free_ib_conn_res(struct
iser_info("freeing conn %p cma_id %p qp %p\n",
iser_conn, ib_conn->cma_id, ib_conn->qp);

- iser_free_rx_descriptors(iser_conn);
-
if (ib_conn->qp != NULL) {
ib_conn->comp->active_qps--;
rdma_destroy_qp(ib_conn->cma_id);
ib_conn->qp = NULL;
}

- if (destroy_device && device != NULL) {
- iser_device_try_release(device);
- ib_conn->device = NULL;
+ if (destroy) {
+ if (iser_conn->rx_descs)
+ iser_free_rx_descriptors(iser_conn);
+
+ if (device != NULL) {
+ iser_device_try_release(device);
+ ib_conn->device = NULL;
+ }
}
}

@@ -840,7 +843,7 @@ static void iser_disconnected_handler(st
}

static void iser_cleanup_handler(struct rdma_cm_id *cma_id,
- bool destroy_device)
+ bool destroy)
{
struct iser_conn *iser_conn = (struct iser_conn *)cma_id->context;

@@ -850,7 +853,7 @@ static void iser_cleanup_handler(struct
* and flush errors.
*/
iser_disconnected_handler(cma_id);
- iser_free_ib_conn_res(iser_conn, destroy_device);
+ iser_free_ib_conn_res(iser_conn, destroy);
complete(&iser_conn->ib_completion);
};