[PATCH rdma-next 0/3] Remove not possible checks

[PATCH rdma-next 0/3] Remove not possible checks

[Leon Romanovsky]

From: Leon Romanovsky <leonro@nvidia.com>

The iwpm is part of iw_cm module load, it ensures that iwpm is valid
prior to execution of any commands.

This series deletes such checks.

Thanks

Leon Romanovsky (3):
  RDMA/iwcm: Release resources if iw_cm module initialization fails
  RDMA/iwpm: Remove not-needed reference counting
  RDMA/iwpm: Rely on the upper to ensure that requests are valid

 drivers/infiniband/core/iwcm.c      | 19 ++++---
 drivers/infiniband/core/iwpm_msg.c  | 34 +------------
 drivers/infiniband/core/iwpm_util.c | 78 ++++++-----------------------
 drivers/infiniband/core/iwpm_util.h | 18 -------
 4 files changed, 28 insertions(+), 121 deletions(-)

-- 
2.31.1

[PATCH rdma-next 1/3] RDMA/iwcm: Release resources if iw_cm module initialization fails

[Leon Romanovsky]

From: Leon Romanovsky <leonro@nvidia.com>

The failure during iw_cm module initialization partially left the system
with unreleased memory and other resources. Rewrite the module init/exit
routines in such way that netlink commands will be opened only after
successful initialization.

Fixes: b493d91d333e ("iwcm: common code for port mapper")
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
 drivers/infiniband/core/iwcm.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/infiniband/core/iwcm.c b/drivers/infiniband/core/iwcm.c
index 42261152b489..2b47073c61a6 100644
--- a/drivers/infiniband/core/iwcm.c
+++ b/drivers/infiniband/core/iwcm.c
@@ -1186,29 +1186,34 @@ static int __init iw_cm_init(void)
 
 	ret = iwpm_init(RDMA_NL_IWCM);
 	if (ret)
-		pr_err("iw_cm: couldn't init iwpm\n");
-	else
-		rdma_nl_register(RDMA_NL_IWCM, iwcm_nl_cb_table);
+		return ret;
+
 	iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", 0);
 	if (!iwcm_wq)
-		return -ENOMEM;
+		goto err_alloc;
 
 	iwcm_ctl_table_hdr = register_net_sysctl(&init_net, "net/iw_cm",
 						 iwcm_ctl_table);
 	if (!iwcm_ctl_table_hdr) {
 		pr_err("iw_cm: couldn't register sysctl paths\n");
-		destroy_workqueue(iwcm_wq);
-		return -ENOMEM;
+		goto err_sysctl;
 	}
 
+	rdma_nl_register(RDMA_NL_IWCM, iwcm_nl_cb_table);
 	return 0;
+
+err_sysctl:
+	destroy_workqueue(iwcm_wq);
+err_alloc:
+	iwpm_exit(RDMA_NL_IWCM);
+	return -ENOMEM;
 }
 
 static void __exit iw_cm_cleanup(void)
 {
+	rdma_nl_unregister(RDMA_NL_IWCM);
 	unregister_net_sysctl_table(iwcm_ctl_table_hdr);
 	destroy_workqueue(iwcm_wq);
-	rdma_nl_unregister(RDMA_NL_IWCM);
 	iwpm_exit(RDMA_NL_IWCM);
 }
 
-- 
2.31.1

[PATCH rdma-next 2/3] RDMA/iwpm: Remove not-needed reference counting

[Leon Romanovsky]

From: Leon Romanovsky <leonro@nvidia.com>

iwpm_init() and iwpm_exit() are called only once during iw_cm module
load. This makes whole reference count implementation not needed at all.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
 drivers/infiniband/core/iwpm_util.c | 62 ++++++++---------------------
 drivers/infiniband/core/iwpm_util.h |  1 -
 2 files changed, 16 insertions(+), 47 deletions(-)

diff --git a/drivers/infiniband/core/iwpm_util.c b/drivers/infiniband/core/iwpm_util.c
index 3f8c019c7260..45e9aa503a44 100644
--- a/drivers/infiniband/core/iwpm_util.c
+++ b/drivers/infiniband/core/iwpm_util.c
@@ -48,7 +48,6 @@ static DEFINE_SPINLOCK(iwpm_mapinfo_lock);
 static struct hlist_head *iwpm_reminfo_bucket;
 static DEFINE_SPINLOCK(iwpm_reminfo_lock);
 
-static DEFINE_MUTEX(iwpm_admin_lock);
 static struct iwpm_admin_data iwpm_admin;
 
 /**
@@ -59,39 +58,22 @@ static struct iwpm_admin_data iwpm_admin;
  */
 int iwpm_init(u8 nl_client)
 {
-	int ret = 0;
-	mutex_lock(&iwpm_admin_lock);
-	if (!refcount_read(&iwpm_admin.refcount)) {
-		iwpm_hash_bucket = kcalloc(IWPM_MAPINFO_HASH_SIZE,
-					   sizeof(struct hlist_head),
-					   GFP_KERNEL);
-		if (!iwpm_hash_bucket) {
-			ret = -ENOMEM;
-			goto init_exit;
-		}
-		iwpm_reminfo_bucket = kcalloc(IWPM_REMINFO_HASH_SIZE,
-					      sizeof(struct hlist_head),
-					      GFP_KERNEL);
-		if (!iwpm_reminfo_bucket) {
-			kfree(iwpm_hash_bucket);
-			ret = -ENOMEM;
-			goto init_exit;
-		}
+	iwpm_hash_bucket = kcalloc(IWPM_MAPINFO_HASH_SIZE,
+				   sizeof(struct hlist_head), GFP_KERNEL);
+	if (!iwpm_hash_bucket)
+		return -ENOMEM;
 
-		refcount_set(&iwpm_admin.refcount, 1);
-	} else {
-		refcount_inc(&iwpm_admin.refcount);
+	iwpm_reminfo_bucket = kcalloc(IWPM_REMINFO_HASH_SIZE,
+				      sizeof(struct hlist_head), GFP_KERNEL);
+	if (!iwpm_reminfo_bucket) {
+		kfree(iwpm_hash_bucket);
+		return -ENOMEM;
 	}
 
-init_exit:
-	mutex_unlock(&iwpm_admin_lock);
-	if (!ret) {
-		iwpm_set_valid(nl_client, 1);
-		iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
-		pr_debug("%s: Mapinfo and reminfo tables are created\n",
-				__func__);
-	}
-	return ret;
+	iwpm_set_valid(nl_client, 1);
+	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
+	pr_debug("%s: Mapinfo and reminfo tables are created\n", __func__);
+	return 0;
 }
 
 static void free_hash_bucket(void);
@@ -105,21 +87,9 @@ static void free_reminfo_bucket(void);
  */
 int iwpm_exit(u8 nl_client)
 {
-
-	if (!iwpm_valid_client(nl_client))
-		return -EINVAL;
-	mutex_lock(&iwpm_admin_lock);
-	if (!refcount_read(&iwpm_admin.refcount)) {
-		mutex_unlock(&iwpm_admin_lock);
-		pr_err("%s Incorrect usage - negative refcount\n", __func__);
-		return -EINVAL;
-	}
-	if (refcount_dec_and_test(&iwpm_admin.refcount)) {
-		free_hash_bucket();
-		free_reminfo_bucket();
-		pr_debug("%s: Resources are destroyed\n", __func__);
-	}
-	mutex_unlock(&iwpm_admin_lock);
+	free_hash_bucket();
+	free_reminfo_bucket();
+	pr_debug("%s: Resources are destroyed\n", __func__);
 	iwpm_set_valid(nl_client, 0);
 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
 	return 0;
diff --git a/drivers/infiniband/core/iwpm_util.h b/drivers/infiniband/core/iwpm_util.h
index e201835de733..e2eacc017078 100644
--- a/drivers/infiniband/core/iwpm_util.h
+++ b/drivers/infiniband/core/iwpm_util.h
@@ -90,7 +90,6 @@ struct iwpm_remote_info {
 };
 
 struct iwpm_admin_data {
-	refcount_t refcount;
 	atomic_t nlmsg_seq;
 	int      client_list[RDMA_NL_NUM_CLIENTS];
 	u32      reg_list[RDMA_NL_NUM_CLIENTS];
-- 
2.31.1

[PATCH rdma-next 3/3] RDMA/iwpm: Rely on the upper to ensure that requests are valid

[Leon Romanovsky]

From: Leon Romanovsky <leonro@nvidia.com>

The iwpw has only one netlink client, which is iw_cm. That client
is registered when the iw_cm module is loaded. The module load is
triggered before any use of EXPORT_SYMBOL or netlink operation and
it ensures that the iwpm is valid.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
 drivers/infiniband/core/iwpm_msg.c  | 34 +----------------------------
 drivers/infiniband/core/iwpm_util.c | 18 ---------------
 drivers/infiniband/core/iwpm_util.h | 17 ---------------
 3 files changed, 1 insertion(+), 68 deletions(-)

diff --git a/drivers/infiniband/core/iwpm_msg.c b/drivers/infiniband/core/iwpm_msg.c
index 12a9816fc0e2..3c9a9869212b 100644
--- a/drivers/infiniband/core/iwpm_msg.c
+++ b/drivers/infiniband/core/iwpm_msg.c
@@ -69,10 +69,6 @@ int iwpm_register_pid(struct iwpm_dev_data *pm_msg, u8 nl_client)
 	const char *err_str = "";
 	int ret = -EINVAL;
 
-	if (!iwpm_valid_client(nl_client)) {
-		err_str = "Invalid port mapper client";
-		goto pid_query_error;
-	}
 	if (iwpm_check_registration(nl_client, IWPM_REG_VALID) ||
 			iwpm_user_pid == IWPM_PID_UNAVAILABLE)
 		return 0;
@@ -153,10 +149,6 @@ int iwpm_add_mapping(struct iwpm_sa_data *pm_msg, u8 nl_client)
 	const char *err_str = "";
 	int ret = -EINVAL;
 
-	if (!iwpm_valid_client(nl_client)) {
-		err_str = "Invalid port mapper client";
-		goto add_mapping_error;
-	}
 	if (!iwpm_valid_pid())
 		return 0;
 	if (!iwpm_check_registration(nl_client, IWPM_REG_VALID)) {
@@ -240,10 +232,6 @@ int iwpm_add_and_query_mapping(struct iwpm_sa_data *pm_msg, u8 nl_client)
 	const char *err_str = "";
 	int ret = -EINVAL;
 
-	if (!iwpm_valid_client(nl_client)) {
-		err_str = "Invalid port mapper client";
-		goto query_mapping_error;
-	}
 	if (!iwpm_valid_pid())
 		return 0;
 	if (!iwpm_check_registration(nl_client, IWPM_REG_VALID)) {
@@ -331,10 +319,6 @@ int iwpm_remove_mapping(struct sockaddr_storage *local_addr, u8 nl_client)
 	const char *err_str = "";
 	int ret = -EINVAL;
 
-	if (!iwpm_valid_client(nl_client)) {
-		err_str = "Invalid port mapper client";
-		goto remove_mapping_error;
-	}
 	if (!iwpm_valid_pid())
 		return 0;
 	if (iwpm_check_registration(nl_client, IWPM_REG_UNDEF)) {
@@ -444,8 +428,7 @@ int iwpm_register_pid_cb(struct sk_buff *skb, struct netlink_callback *cb)
 	atomic_set(&echo_nlmsg_seq, cb->nlh->nlmsg_seq);
 	pr_debug("%s: iWarp Port Mapper (pid = %d) is available!\n",
 			__func__, iwpm_user_pid);
-	if (iwpm_valid_client(nl_client))
-		iwpm_set_registration(nl_client, IWPM_REG_VALID);
+	iwpm_set_registration(nl_client, IWPM_REG_VALID);
 register_pid_response_exit:
 	nlmsg_request->request_done = 1;
 	/* always for found nlmsg_request */
@@ -649,11 +632,6 @@ int iwpm_remote_info_cb(struct sk_buff *skb, struct netlink_callback *cb)
 		return ret;
 
 	nl_client = RDMA_NL_GET_CLIENT(cb->nlh->nlmsg_type);
-	if (!iwpm_valid_client(nl_client)) {
-		pr_info("%s: Invalid port mapper client = %u\n",
-				__func__, nl_client);
-		return ret;
-	}
 	atomic_set(&echo_nlmsg_seq, cb->nlh->nlmsg_seq);
 
 	local_sockaddr = (struct sockaddr_storage *)
@@ -736,11 +714,6 @@ int iwpm_mapping_info_cb(struct sk_buff *skb, struct netlink_callback *cb)
 		return ret;
 	}
 	nl_client = RDMA_NL_GET_CLIENT(cb->nlh->nlmsg_type);
-	if (!iwpm_valid_client(nl_client)) {
-		pr_info("%s: Invalid port mapper client = %u\n",
-				__func__, nl_client);
-		return ret;
-	}
 	iwpm_set_registration(nl_client, IWPM_REG_INCOMPL);
 	atomic_set(&echo_nlmsg_seq, cb->nlh->nlmsg_seq);
 	iwpm_user_pid = cb->nlh->nlmsg_pid;
@@ -863,11 +836,6 @@ int iwpm_hello_cb(struct sk_buff *skb, struct netlink_callback *cb)
 	}
 	abi_version = nla_get_u16(nltb[IWPM_NLA_HELLO_ABI_VERSION]);
 	nl_client = RDMA_NL_GET_CLIENT(cb->nlh->nlmsg_type);
-	if (!iwpm_valid_client(nl_client)) {
-		pr_info("%s: Invalid port mapper client = %u\n",
-				__func__, nl_client);
-		return ret;
-	}
 	iwpm_set_registration(nl_client, IWPM_REG_INCOMPL);
 	atomic_set(&echo_nlmsg_seq, cb->nlh->nlmsg_seq);
 	iwpm_ulib_version = min_t(u16, IWPM_UABI_VERSION, abi_version);
diff --git a/drivers/infiniband/core/iwpm_util.c b/drivers/infiniband/core/iwpm_util.c
index 45e9aa503a44..54f4feb604d8 100644
--- a/drivers/infiniband/core/iwpm_util.c
+++ b/drivers/infiniband/core/iwpm_util.c
@@ -70,7 +70,6 @@ int iwpm_init(u8 nl_client)
 		return -ENOMEM;
 	}
 
-	iwpm_set_valid(nl_client, 1);
 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
 	pr_debug("%s: Mapinfo and reminfo tables are created\n", __func__);
 	return 0;
@@ -90,7 +89,6 @@ int iwpm_exit(u8 nl_client)
 	free_hash_bucket();
 	free_reminfo_bucket();
 	pr_debug("%s: Resources are destroyed\n", __func__);
-	iwpm_set_valid(nl_client, 0);
 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
 	return 0;
 }
@@ -115,8 +113,6 @@ int iwpm_create_mapinfo(struct sockaddr_storage *local_sockaddr,
 	unsigned long flags;
 	int ret = -EINVAL;
 
-	if (!iwpm_valid_client(nl_client))
-		return ret;
 	map_info = kzalloc(sizeof(struct iwpm_mapping_info), GFP_KERNEL);
 	if (!map_info)
 		return -ENOMEM;
@@ -276,10 +272,6 @@ int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
 	unsigned long flags;
 	int ret = -EINVAL;
 
-	if (!iwpm_valid_client(nl_client)) {
-		pr_info("%s: Invalid client = %u\n", __func__, nl_client);
-		return ret;
-	}
 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
 	if (iwpm_reminfo_bucket) {
 		hash_bucket_head = get_reminfo_hash_bucket(
@@ -394,16 +386,6 @@ int iwpm_get_nlmsg_seq(void)
 	return atomic_inc_return(&iwpm_admin.nlmsg_seq);
 }
 
-int iwpm_valid_client(u8 nl_client)
-{
-	return iwpm_admin.client_list[nl_client];
-}
-
-void iwpm_set_valid(u8 nl_client, int valid)
-{
-	iwpm_admin.client_list[nl_client] = valid;
-}
-
 /* valid client */
 u32 iwpm_get_registration(u8 nl_client)
 {
diff --git a/drivers/infiniband/core/iwpm_util.h b/drivers/infiniband/core/iwpm_util.h
index e2eacc017078..3a42ad43056e 100644
--- a/drivers/infiniband/core/iwpm_util.h
+++ b/drivers/infiniband/core/iwpm_util.h
@@ -91,7 +91,6 @@ struct iwpm_remote_info {
 
 struct iwpm_admin_data {
 	atomic_t nlmsg_seq;
-	int      client_list[RDMA_NL_NUM_CLIENTS];
 	u32      reg_list[RDMA_NL_NUM_CLIENTS];
 };
 
@@ -146,22 +145,6 @@ int iwpm_get_nlmsg_seq(void);
  */
 void iwpm_add_remote_info(struct iwpm_remote_info *reminfo);
 
-/**
- * iwpm_valid_client - Check if the port mapper client is valid
- * @nl_client: The index of the netlink client
- *
- * Valid clients need to call iwpm_init() before using
- * the port mapper
- */
-int iwpm_valid_client(u8 nl_client);
-
-/**
- * iwpm_set_valid - Set the port mapper client to valid or not
- * @nl_client: The index of the netlink client
- * @valid: 1 if valid or 0 if invalid
- */
-void iwpm_set_valid(u8 nl_client, int valid);
-
 /**
  * iwpm_check_registration - Check if the client registration
  *			      matches the given one
-- 
2.31.1

Re: [PATCH rdma-next 0/3] Remove not possible checks

[Jason Gunthorpe]

On Fri, Jul 23, 2021 at 05:08:54PM +0300, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@nvidia.com>
> 
> The iwpm is part of iw_cm module load, it ensures that iwpm is valid
> prior to execution of any commands.
> 
> This series deletes such checks.
> 
> Thanks
> 
> Leon Romanovsky (3):
>   RDMA/iwcm: Release resources if iw_cm module initialization fails
>   RDMA/iwpm: Remove not-needed reference counting
>   RDMA/iwpm: Rely on the upper to ensure that requests are valid

Applied to for-next, thanks

Jason