[PATCH 13/29] IB/mlx4: Split a condition check in five functions

From: SF Markus Elfring
Date: Sat Feb 18 2017 - 16:08:53 EST


From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Sat, 18 Feb 2017 14:43:34 +0100

The kfree() function was called in up to two cases during error handling
even if the passed variable contained a null pointer.

* Split a condition check for memory allocation failures.

* Adjust jump targets according to the Linux coding style convention.

* Delete initialisations for variables at the beginning
which became unnecessary with this refactoring.

Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/hw/mlx4/main.c | 90 +++++++++++++++++++++++++--------------
1 file changed, 59 insertions(+), 31 deletions(-)

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index b3b5ded85166..c0c299ffa0f6 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -432,8 +432,8 @@ static int mlx4_ib_query_device(struct ib_device *ibdev,
struct ib_udata *uhw)
{
struct mlx4_ib_dev *dev = to_mdev(ibdev);
- struct ib_smp *in_mad = NULL;
- struct ib_smp *out_mad = NULL;
+ struct ib_smp *in_mad;
+ struct ib_smp *out_mad;
int err;
int have_ib_ports;
struct mlx4_uverbs_ex_query_device cmd;
@@ -458,10 +458,14 @@ static int mlx4_ib_query_device(struct ib_device *ibdev,
resp.response_length = offsetof(typeof(resp), response_length) +
sizeof(resp.response_length);
in_mad = kzalloc(sizeof(*in_mad), GFP_KERNEL);
+ if (!in_mad)
+ return -ENOMEM;
+
out_mad = kmalloc(sizeof(*out_mad), GFP_KERNEL);
- err = -ENOMEM;
- if (!in_mad || !out_mad)
- goto out;
+ if (!out_mad) {
+ err = -ENOMEM;
+ goto free_in_mad;
+ }

init_query_mad(in_mad);
in_mad->attr_id = IB_SMP_ATTR_NODE_INFO;
@@ -570,9 +574,9 @@ static int mlx4_ib_query_device(struct ib_device *ibdev,
goto out;
}
out:
- kfree(in_mad);
kfree(out_mad);
-
+free_in_mad:
+ kfree(in_mad);
return err;
}

@@ -588,16 +592,21 @@ mlx4_ib_port_link_layer(struct ib_device *device, u8 port_num)
static int ib_link_query_port(struct ib_device *ibdev, u8 port,
struct ib_port_attr *props, int netw_view)
{
- struct ib_smp *in_mad = NULL;
- struct ib_smp *out_mad = NULL;
+ struct ib_smp *in_mad;
+ struct ib_smp *out_mad;
int ext_active_speed;
int mad_ifc_flags = MLX4_MAD_IFC_IGNORE_KEYS;
- int err = -ENOMEM;
+ int err;

in_mad = kzalloc(sizeof(*in_mad), GFP_KERNEL);
+ if (!in_mad)
+ return -ENOMEM;
+
out_mad = kmalloc(sizeof(*out_mad), GFP_KERNEL);
- if (!in_mad || !out_mad)
- goto out;
+ if (!out_mad) {
+ err = -ENOMEM;
+ goto free_in_mad;
+ }

init_query_mad(in_mad);
in_mad->attr_id = IB_SMP_ATTR_PORT_INFO;
@@ -670,8 +679,9 @@ static int ib_link_query_port(struct ib_device *ibdev, u8 port,
props->active_speed = IB_SPEED_SDR;

out:
- kfree(in_mad);
kfree(out_mad);
+free_in_mad:
+ kfree(in_mad);
return err;
}

@@ -763,17 +773,22 @@ static int mlx4_ib_query_port(struct ib_device *ibdev, u8 port,
int __mlx4_ib_query_gid(struct ib_device *ibdev, u8 port, int index,
union ib_gid *gid, int netw_view)
{
- struct ib_smp *in_mad = NULL;
- struct ib_smp *out_mad = NULL;
- int err = -ENOMEM;
+ struct ib_smp *in_mad;
+ struct ib_smp *out_mad;
+ int err;
struct mlx4_ib_dev *dev = to_mdev(ibdev);
int clear = 0;
int mad_ifc_flags = MLX4_MAD_IFC_IGNORE_KEYS;

in_mad = kzalloc(sizeof(*in_mad), GFP_KERNEL);
+ if (!in_mad)
+ return -ENOMEM;
+
out_mad = kmalloc(sizeof(*out_mad), GFP_KERNEL);
- if (!in_mad || !out_mad)
- goto out;
+ if (!out_mad) {
+ err = -ENOMEM;
+ goto free_in_mad;
+ }

init_query_mad(in_mad);
in_mad->attr_id = IB_SMP_ATTR_PORT_INFO;
@@ -811,8 +826,9 @@ int __mlx4_ib_query_gid(struct ib_device *ibdev, u8 port, int index,
out:
if (clear)
memset(gid->raw + 8, 0, 8);
- kfree(in_mad);
kfree(out_mad);
+free_in_mad:
+ kfree(in_mad);
return err;
}

@@ -902,15 +918,20 @@ static void mlx4_init_sl2vl_tbl(struct mlx4_ib_dev *mdev)
int __mlx4_ib_query_pkey(struct ib_device *ibdev, u8 port, u16 index,
u16 *pkey, int netw_view)
{
- struct ib_smp *in_mad = NULL;
- struct ib_smp *out_mad = NULL;
+ struct ib_smp *in_mad;
+ struct ib_smp *out_mad;
int mad_ifc_flags = MLX4_MAD_IFC_IGNORE_KEYS;
- int err = -ENOMEM;
+ int err;

in_mad = kzalloc(sizeof(*in_mad), GFP_KERNEL);
+ if (!in_mad)
+ return -ENOMEM;
+
out_mad = kmalloc(sizeof(*out_mad), GFP_KERNEL);
- if (!in_mad || !out_mad)
- goto out;
+ if (!out_mad) {
+ err = -ENOMEM;
+ goto free_in_mad;
+ }

init_query_mad(in_mad);
in_mad->attr_id = IB_SMP_ATTR_PKEY_TABLE;
@@ -927,8 +948,9 @@ int __mlx4_ib_query_pkey(struct ib_device *ibdev, u8 port, u16 index,
*pkey = be16_to_cpu(((__be16 *) out_mad->data)[index % 32]);

out:
- kfree(in_mad);
kfree(out_mad);
+free_in_mad:
+ kfree(in_mad);
return err;
}

@@ -2083,15 +2105,20 @@ static int mlx4_ib_mcg_detach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)

static int init_node_data(struct mlx4_ib_dev *dev)
{
- struct ib_smp *in_mad = NULL;
- struct ib_smp *out_mad = NULL;
+ struct ib_smp *in_mad;
+ struct ib_smp *out_mad;
int mad_ifc_flags = MLX4_MAD_IFC_IGNORE_KEYS;
- int err = -ENOMEM;
+ int err;

in_mad = kzalloc(sizeof(*in_mad), GFP_KERNEL);
+ if (!in_mad)
+ return -ENOMEM;
+
out_mad = kmalloc(sizeof(*out_mad), GFP_KERNEL);
- if (!in_mad || !out_mad)
- goto out;
+ if (!out_mad) {
+ err = -ENOMEM;
+ goto free_in_mad;
+ }

init_query_mad(in_mad);
in_mad->attr_id = IB_SMP_ATTR_NODE_DESC;
@@ -2114,8 +2141,9 @@ static int init_node_data(struct mlx4_ib_dev *dev)
memcpy(&dev->ib_dev.node_guid, out_mad->data + 12, 8);

out:
- kfree(in_mad);
kfree(out_mad);
+free_in_mad:
+ kfree(in_mad);
return err;
}

--
2.11.1