net/mlx5e: Export sharing of mod headers to a new file

Refactor sharing of mod headers to new file and while there,
remove spin lock and flows list, as this is only used for warn on.

Use the generic API in the next patch to re-use tuple modify headers
for identical modify actions,

Signed-off-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

1 files changed, 157 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/mod_hdr.c b/drivers/net/ethernet/mellanox/mlx5/core/en/mod_hdr.c
new file mode 100644
index 000000000000..7edde4d536fd
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/mod_hdr.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+// Copyright (c) 2020 Mellanox Technologies
+
+#include <linux/jhash.h>
+#include "mod_hdr.h"
+
+#define MLX5_MH_ACT_SZ MLX5_UN_SZ_BYTES(set_add_copy_action_in_auto)
+
+struct mod_hdr_key {
+	int num_actions;
+	void *actions;
+};
+
+struct mlx5e_mod_hdr_handle {
+	/* a node of a hash table which keeps all the mod_hdr entries */
+	struct hlist_node mod_hdr_hlist;
+
+	struct mod_hdr_key key;
+
+	struct mlx5_modify_hdr *modify_hdr;
+
+	refcount_t refcnt;
+	struct completion res_ready;
+	int compl_result;
+};
+
+static u32 hash_mod_hdr_info(struct mod_hdr_key *key)
+{
+	return jhash(key->actions,
+		     key->num_actions * MLX5_MH_ACT_SZ, 0);
+}
+
+static int cmp_mod_hdr_info(struct mod_hdr_key *a, struct mod_hdr_key *b)
+{
+	if (a->num_actions != b->num_actions)
+		return 1;
+
+	return memcmp(a->actions, b->actions,
+		      a->num_actions * MLX5_MH_ACT_SZ);
+}
+
+void mlx5e_mod_hdr_tbl_init(struct mod_hdr_tbl *tbl)
+{
+	mutex_init(&tbl->lock);
+	hash_init(tbl->hlist);
+}
+
+void mlx5e_mod_hdr_tbl_destroy(struct mod_hdr_tbl *tbl)
+{
+	mutex_destroy(&tbl->lock);
+}
+
+static struct mlx5e_mod_hdr_handle *mod_hdr_get(struct mod_hdr_tbl *tbl,
+						struct mod_hdr_key *key,
+						u32 hash_key)
+{
+	struct mlx5e_mod_hdr_handle *mh, *found = NULL;
+
+	hash_for_each_possible(tbl->hlist, mh, mod_hdr_hlist, hash_key) {
+		if (!cmp_mod_hdr_info(&mh->key, key)) {
+			refcount_inc(&mh->refcnt);
+			found = mh;
+			break;
+		}
+	}
+
+	return found;
+}
+
+struct mlx5e_mod_hdr_handle *
+mlx5e_mod_hdr_attach(struct mlx5_core_dev *mdev,
+		     struct mod_hdr_tbl *tbl,
+		     enum mlx5_flow_namespace_type namespace,
+		     struct mlx5e_tc_mod_hdr_acts *mod_hdr_acts)
+{
+	int num_actions, actions_size, err;
+	struct mlx5e_mod_hdr_handle *mh;
+	struct mod_hdr_key key;
+	u32 hash_key;
+
+	num_actions  = mod_hdr_acts->num_actions;
+	actions_size = MLX5_MH_ACT_SZ * num_actions;
+
+	key.actions = mod_hdr_acts->actions;
+	key.num_actions = num_actions;
+
+	hash_key = hash_mod_hdr_info(&key);
+
+	mutex_lock(&tbl->lock);
+	mh = mod_hdr_get(tbl, &key, hash_key);
+	if (mh) {
+		mutex_unlock(&tbl->lock);
+		wait_for_completion(&mh->res_ready);
+
+		if (mh->compl_result < 0) {
+			err = -EREMOTEIO;
+			goto attach_header_err;
+		}
+		goto attach_header;
+	}
+
+	mh = kzalloc(sizeof(*mh) + actions_size, GFP_KERNEL);
+	if (!mh) {
+		mutex_unlock(&tbl->lock);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	mh->key.actions = (void *)mh + sizeof(*mh);
+	memcpy(mh->key.actions, key.actions, actions_size);
+	mh->key.num_actions = num_actions;
+	refcount_set(&mh->refcnt, 1);
+	init_completion(&mh->res_ready);
+
+	hash_add(tbl->hlist, &mh->mod_hdr_hlist, hash_key);
+	mutex_unlock(&tbl->lock);
+
+	mh->modify_hdr = mlx5_modify_header_alloc(mdev, namespace,
+						  mh->key.num_actions,
+						  mh->key.actions);
+	if (IS_ERR(mh->modify_hdr)) {
+		err = PTR_ERR(mh->modify_hdr);
+		mh->compl_result = err;
+		goto alloc_header_err;
+	}
+	mh->compl_result = 1;
+	complete_all(&mh->res_ready);
+
+attach_header:
+	return mh;
+
+alloc_header_err:
+	complete_all(&mh->res_ready);
+attach_header_err:
+	mlx5e_mod_hdr_detach(mdev, tbl, mh);
+	return ERR_PTR(err);
+}
+
+void mlx5e_mod_hdr_detach(struct mlx5_core_dev *mdev,
+			  struct mod_hdr_tbl *tbl,
+			  struct mlx5e_mod_hdr_handle *mh)
+{
+	if (!refcount_dec_and_mutex_lock(&mh->refcnt, &tbl->lock))
+		return;
+	hash_del(&mh->mod_hdr_hlist);
+	mutex_unlock(&tbl->lock);
+
+	if (mh->compl_result > 0)
+		mlx5_modify_header_dealloc(mdev, mh->modify_hdr);
+
+	kfree(mh);
+}
+
+struct mlx5_modify_hdr *mlx5e_mod_hdr_get(struct mlx5e_mod_hdr_handle *mh)
+{
+	return mh->modify_hdr;
+}
+