[PATCH 5.10 351/545] RDMA/srpt: Introduce a reference count in struct srpt_device

Greg Kroah-Hartman
2022-08-19T16:34:03Z

From: Bart Van Assche <bvanassche@acm.org>

[ Upstream commit aa7dfbb41b5a60ab90e244d6f586b8cb5c791c3e ]

This will be used to keep struct srpt_device around as long as either the
RDMA port exists or a LIO target port is associated with the struct
srpt_device.

Link: https://lore.kernel.org/r/20220727193415.1583860-3-bvanassche@acm.org
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/infiniband/ulp/srpt/ib_srpt.c | 17 +++++++++++++++--
drivers/infiniband/ulp/srpt/ib_srpt.h | 2 ++
2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 4cecdcee606a..211d4e82e4ba 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -3101,6 +3101,18 @@ static int srpt_use_srq(struct srpt_device *sdev, bool use_srq)
return ret;
}

+static void srpt_free_sdev(struct kref *refcnt)
+{
+ struct srpt_device *sdev = container_of(refcnt, typeof(*sdev), refcnt);
+
+ kfree(sdev);
+}
+
+static void srpt_sdev_put(struct srpt_device *sdev)
+{
+ kref_put(&sdev->refcnt, srpt_free_sdev);
+}
+
/**
* srpt_add_one - InfiniBand device addition callback function
* @device: Describes a HCA.
@@ -3118,6 +3130,7 @@ static int srpt_add_one(struct ib_device *device)
if (!sdev)
return -ENOMEM;

+ kref_init(&sdev->refcnt);
sdev->device = device;
mutex_init(&sdev->sdev_mutex);

@@ -3213,7 +3226,7 @@ static int srpt_add_one(struct ib_device *device)
srpt_free_srq(sdev);
ib_dealloc_pd(sdev->pd);
free_dev:
- kfree(sdev);
+ srpt_sdev_put(sdev);
pr_info("%s(%s) failed.\n", __func__, dev_name(&device->dev));
return ret;
}
@@ -3257,7 +3270,7 @@ static void srpt_remove_one(struct ib_device *device, void *client_data)

ib_dealloc_pd(sdev->pd);

- kfree(sdev);
+ srpt_sdev_put(sdev);
}

static struct ib_client srpt_client = {
diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.h b/drivers/infiniband/ulp/srpt/ib_srpt.h
index 1d28f13196c9..978a338f1f0e 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.h
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.h
@@ -434,6 +434,7 @@ struct srpt_port {

/**
* struct srpt_device - information associated by SRPT with a single HCA
+ * @refcnt: Reference count for this device.
* @device: Backpointer to the struct ib_device managed by the IB core.
* @pd: IB protection domain.
* @lkey: L_Key (local key) with write access to all local memory.
@@ -449,6 +450,7 @@ struct srpt_port {
* @port: Information about the ports owned by this HCA.
*/
struct srpt_device {
+ struct kref refcnt;
struct ib_device *device;
struct ib_pd *pd;
u32 lkey;
--
2.35.1