[PATCH AUTOSEL 5.13 156/219] net: Fix offloading indirect devices dependency on qdisc order creation

Sasha Levin
2021-09-09T12:25:25Z

From: Eli Cohen <elic@nvidia.com>

[ Upstream commit 74fc4f828769cca1c3be89ea92cb88feaa27ef52 ]

Currently, when creating an ingress qdisc on an indirect device before
the driver registered for callbacks, the driver will not have a chance
to register its filter configuration callbacks.

To fix that, modify the code such that it keeps track of all the ingress
qdiscs that call flow_indr_dev_setup_offload(). When a driver calls
flow_indr_dev_register(), go through the list of tracked ingress qdiscs
and call the driver callback entry point so as to give it a chance to
register its callback.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/net/flow_offload.h | 1 +
net/core/flow_offload.c | 89 ++++++++++++++++++++++++++-
net/netfilter/nf_flow_table_offload.c | 1 +
net/netfilter/nf_tables_offload.c | 1 +
net/sched/cls_api.c | 1 +
5 files changed, 92 insertions(+), 1 deletion(-)

diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
index dc5c1e69cd9f..26788244d75b 100644
--- a/include/net/flow_offload.h
+++ b/include/net/flow_offload.h
@@ -451,6 +451,7 @@ struct flow_block_offload {
struct list_head *driver_block_list;
struct netlink_ext_ack *extack;
struct Qdisc *sch;
+ struct list_head *cb_list_head;
};

enum tc_setup_type;
diff --git a/net/core/flow_offload.c b/net/core/flow_offload.c
index 715b67f6c62f..e3f0d5906811 100644
--- a/net/core/flow_offload.c
+++ b/net/core/flow_offload.c
@@ -321,6 +321,7 @@ EXPORT_SYMBOL(flow_block_cb_setup_simple);
static DEFINE_MUTEX(flow_indr_block_lock);
static LIST_HEAD(flow_block_indr_list);
static LIST_HEAD(flow_block_indr_dev_list);
+static LIST_HEAD(flow_indir_dev_list);

struct flow_indr_dev {
struct list_head list;
@@ -346,6 +347,33 @@ static struct flow_indr_dev *flow_indr_dev_alloc(flow_indr_block_bind_cb_t *cb,
return indr_dev;
}

+struct flow_indir_dev_info {
+ void *data;
+ struct net_device *dev;
+ struct Qdisc *sch;
+ enum tc_setup_type type;
+ void (*cleanup)(struct flow_block_cb *block_cb);
+ struct list_head list;
+ enum flow_block_command command;
+ enum flow_block_binder_type binder_type;
+ struct list_head *cb_list;
+};
+
+static void existing_qdiscs_register(flow_indr_block_bind_cb_t *cb, void *cb_priv)
+{
+ struct flow_block_offload bo;
+ struct flow_indir_dev_info *cur;
+
+ list_for_each_entry(cur, &flow_indir_dev_list, list) {
+ memset(&bo, 0, sizeof(bo));
+ bo.command = cur->command;
+ bo.binder_type = cur->binder_type;
+ INIT_LIST_HEAD(&bo.cb_list);
+ cb(cur->dev, cur->sch, cb_priv, cur->type, &bo, cur->data, cur->cleanup);
+ list_splice(&bo.cb_list, cur->cb_list);
+ }
+}
+
int flow_indr_dev_register(flow_indr_block_bind_cb_t *cb, void *cb_priv)
{
struct flow_indr_dev *indr_dev;
@@ -367,6 +395,7 @@ int flow_indr_dev_register(flow_indr_block_bind_cb_t *cb, void *cb_priv)
}

list_add(&indr_dev->list, &flow_block_indr_dev_list);
+ existing_qdiscs_register(cb, cb_priv);
mutex_unlock(&flow_indr_block_lock);

return 0;
@@ -463,7 +492,59 @@ struct flow_block_cb *flow_indr_block_cb_alloc(flow_setup_cb_t *cb,
}
EXPORT_SYMBOL(flow_indr_block_cb_alloc);

-int flow_indr_dev_setup_offload(struct net_device *dev, struct Qdisc *sch,
+static struct flow_indir_dev_info *find_indir_dev(void *data)
+{
+ struct flow_indir_dev_info *cur;
+
+ list_for_each_entry(cur, &flow_indir_dev_list, list) {
+ if (cur->data == data)
+ return cur;
+ }
+ return NULL;
+}
+
+static int indir_dev_add(void *data, struct net_device *dev, struct Qdisc *sch,
+ enum tc_setup_type type, void (*cleanup)(struct flow_block_cb *block_cb),
+ struct flow_block_offload *bo)
+{
+ struct flow_indir_dev_info *info;
+
+ info = find_indir_dev(data);
+ if (info)
+ return -EEXIST;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ info->data = data;
+ info->dev = dev;
+ info->sch = sch;
+ info->type = type;
+ info->cleanup = cleanup;
+ info->command = bo->command;
+ info->binder_type = bo->binder_type;
+ info->cb_list = bo->cb_list_head;
+
+ list_add(&info->list, &flow_indir_dev_list);
+ return 0;
+}
+
+static int indir_dev_remove(void *data)
+{
+ struct flow_indir_dev_info *info;
+
+ info = find_indir_dev(data);
+ if (!info)
+ return -ENOENT;
+
+ list_del(&info->list);
+
+ kfree(info);
+ return 0;
+}
+
+int flow_indr_dev_setup_offload(struct net_device *dev, struct Qdisc *sch,
enum tc_setup_type type, void *data,
struct flow_block_offload *bo,
void (*cleanup)(struct flow_block_cb *block_cb))
@@ -471,6 +552,12 @@ int flow_indr_dev_setup_offload(struct net_device *dev, struct Qdisc *sch,
struct flow_indr_dev *this;

mutex_lock(&flow_indr_block_lock);
+
+ if (bo->command == FLOW_BLOCK_BIND)
+ indir_dev_add(data, dev, sch, type, cleanup, bo);
+ else if (bo->command == FLOW_BLOCK_UNBIND)
+ indir_dev_remove(data);
+
list_for_each_entry(this, &flow_block_indr_dev_list, list)
this->cb(dev, sch, this->cb_priv, type, bo, data, cleanup);

diff --git a/net/netfilter/nf_flow_table_offload.c b/net/netfilter/nf_flow_table_offload.c
index 528b2f172684..0587f071e504 100644
--- a/net/netfilter/nf_flow_table_offload.c
+++ b/net/netfilter/nf_flow_table_offload.c
@@ -1097,6 +1097,7 @@ static void nf_flow_table_block_offload_init(struct flow_block_offload *bo,
bo->command = cmd;
bo->binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
bo->extack = extack;
+ bo->cb_list_head = &flowtable->flow_block.cb_list;
INIT_LIST_HEAD(&bo->cb_list);
}

diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c
index b58d73a96523..9656c1646222 100644
--- a/net/netfilter/nf_tables_offload.c
+++ b/net/netfilter/nf_tables_offload.c
@@ -353,6 +353,7 @@ static void nft_flow_block_offload_init(struct flow_block_offload *bo,
bo->command = cmd;
bo->binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
bo->extack = extack;
+ bo->cb_list_head = &basechain->flow_block.cb_list;
INIT_LIST_HEAD(&bo->cb_list);
}

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index e3e79e9bd706..9b276d14be4c 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -634,6 +634,7 @@ static void tcf_block_offload_init(struct flow_block_offload *bo,
bo->block_shared = shared;
bo->extack = extack;
bo->sch = sch;
+ bo->cb_list_head = &flow_block->cb_list;
INIT_LIST_HEAD(&bo->cb_list);
}

--
2.30.2