[PATCH v2 09/17] IB/mlx4: Split a condition check in six functions

From: SF Markus Elfring
Date: Fri Apr 21 2017 - 14:41:24 EST


From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Fri, 21 Apr 2017 18:13:16 +0200

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>
---

v2:
Changes were rebased on source files from Linux next-20170421.
These were recombined as requested by Doug Ledford.

drivers/infiniband/hw/mlx4/mad.c | 14 +++---
drivers/infiniband/hw/mlx4/main.c | 90 +++++++++++++++++++++++++--------------
2 files changed, 68 insertions(+), 36 deletions(-)

diff --git a/drivers/infiniband/hw/mlx4/mad.c b/drivers/infiniband/hw/mlx4/mad.c
index 41461aeb7c5e..b26817f0669f 100644
--- a/drivers/infiniband/hw/mlx4/mad.c
+++ b/drivers/infiniband/hw/mlx4/mad.c
@@ -1129,17 +1129,20 @@ static void propagate_pkey_ev(struct mlx4_ib_dev *dev, int port_num,
static void handle_slaves_guid_change(struct mlx4_ib_dev *dev, u8 port_num,
u32 guid_tbl_blk_num, u32 change_bitmap)
{
- struct ib_smp *in_mad = NULL;
- struct ib_smp *out_mad = NULL;
+ struct ib_smp *in_mad;
+ struct ib_smp *out_mad;
u16 i;

if (!mlx4_is_mfunc(dev->dev) || !mlx4_is_master(dev->dev))
return;

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

guid_tbl_blk_num *= 4;

@@ -1172,8 +1175,9 @@ static void handle_slaves_guid_change(struct mlx4_ib_dev *dev, u8 port_num,
}

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

void handle_port_mgmt_change_event(struct work_struct *work)
diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index 8f0e37c4f381..e18e46a68809 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -435,8 +435,8 @@ 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;
@@ -461,10 +461,14 @@ 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;
@@ -573,9 +577,9 @@ 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;
}

@@ -591,16 +595,21 @@ 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;
@@ -673,8 +682,9 @@ 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;
}

@@ -766,17 +776,22 @@ 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;
@@ -814,8 +829,9 @@ 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;
}

@@ -905,15 +921,20 @@ 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;
@@ -930,8 +951,9 @@ 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;
}

@@ -2086,15 +2108,20 @@ 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;
@@ -2117,8 +2144,9 @@ 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;
}

--
2.12.2