[PATCH net-next 7/8] net: microchip: sparx5: Add VCAP locking to protect rules

From: Steen Hegelund
Date: Wed Nov 16 2022 - 04:01:08 EST


This ensures that the VCAP cache and the lists maintained in the VCAP
instance is protected when accessed by different clients.

Signed-off-by: Steen Hegelund <steen.hegelund@xxxxxxxxxxxxx>
---
.../net/ethernet/microchip/sparx5/sparx5_vcap_impl.c | 2 ++
drivers/net/ethernet/microchip/vcap/vcap_api.c | 10 ++++++++++
drivers/net/ethernet/microchip/vcap/vcap_api.h | 1 +
drivers/net/ethernet/microchip/vcap/vcap_api_debugfs.c | 2 ++
4 files changed, 15 insertions(+)

diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_vcap_impl.c b/drivers/net/ethernet/microchip/sparx5/sparx5_vcap_impl.c
index e70ff1aa6d57..0c4d4e6d51e6 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_vcap_impl.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_vcap_impl.c
@@ -579,6 +579,7 @@ static void sparx5_vcap_admin_free(struct vcap_admin *admin)
{
if (!admin)
return;
+ mutex_destroy(&admin->lock);
kfree(admin->cache.keystream);
kfree(admin->cache.maskstream);
kfree(admin->cache.actionstream);
@@ -598,6 +599,7 @@ sparx5_vcap_admin_alloc(struct sparx5 *sparx5, struct vcap_control *ctrl,
INIT_LIST_HEAD(&admin->list);
INIT_LIST_HEAD(&admin->rules);
INIT_LIST_HEAD(&admin->enabled);
+ mutex_init(&admin->lock);
admin->vtype = cfg->vtype;
admin->vinst = cfg->vinst;
admin->lookups = cfg->lookups;
diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api.c b/drivers/net/ethernet/microchip/vcap/vcap_api.c
index 3415605350c9..ac7a32ff755e 100644
--- a/drivers/net/ethernet/microchip/vcap/vcap_api.c
+++ b/drivers/net/ethernet/microchip/vcap/vcap_api.c
@@ -1054,6 +1054,7 @@ int vcap_add_rule(struct vcap_rule *rule)
if (ret)
return ret;
/* Insert the new rule in the list of vcap rules */
+ mutex_lock(&ri->admin->lock);
ret = vcap_insert_rule(ri, &move);
if (ret < 0) {
pr_err("%s:%d: could not insert rule in vcap list: %d\n",
@@ -1072,6 +1073,7 @@ int vcap_add_rule(struct vcap_rule *rule)
if (ret)
pr_err("%s:%d: rule write error: %d\n", __func__, __LINE__, ret);
out:
+ mutex_unlock(&ri->admin->lock);
return ret;
}
EXPORT_SYMBOL_GPL(vcap_add_rule);
@@ -1221,9 +1223,11 @@ int vcap_del_rule(struct vcap_control *vctrl, struct net_device *ndev, u32 id)
gap = vcap_fill_rule_gap(ri);

/* Delete the rule from the list of rules and the cache */
+ mutex_lock(&admin->lock);
list_del(&ri->list);
vctrl->ops->init(ndev, admin, admin->last_used_addr, ri->size + gap);
kfree(ri);
+ mutex_unlock(&admin->lock);

/* Update the last used address, set to default when no rules */
if (list_empty(&admin->rules)) {
@@ -1246,6 +1250,8 @@ int vcap_del_rules(struct vcap_control *vctrl, struct vcap_admin *admin)

if (ret)
return ret;
+
+ mutex_lock(&admin->lock);
list_for_each_entry_safe(ri, next_ri, &admin->rules, list) {
vctrl->ops->init(ri->ndev, admin, ri->addr, ri->size);
list_del(&ri->list);
@@ -1258,6 +1264,7 @@ int vcap_del_rules(struct vcap_control *vctrl, struct vcap_admin *admin)
list_del(&eport->list);
kfree(eport);
}
+ mutex_unlock(&admin->lock);

return 0;
}
@@ -1687,10 +1694,13 @@ int vcap_enable_lookups(struct vcap_control *vctrl, struct net_device *ndev,
if (chain_id) {
if (vcap_is_enabled(admin, ndev, cookie))
return -EADDRINUSE;
+ mutex_lock(&admin->lock);
vcap_enable(admin, ndev, cookie);
} else {
+ mutex_lock(&admin->lock);
vcap_disable(admin, ndev, cookie);
}
+ mutex_unlock(&admin->lock);

return 0;
}
diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api.h b/drivers/net/ethernet/microchip/vcap/vcap_api.h
index e71e7d3d79c2..f4a5ba5ffa87 100644
--- a/drivers/net/ethernet/microchip/vcap/vcap_api.h
+++ b/drivers/net/ethernet/microchip/vcap/vcap_api.h
@@ -167,6 +167,7 @@ struct vcap_admin {
struct list_head list; /* for insertion in vcap_control */
struct list_head rules; /* list of rules */
struct list_head enabled; /* list of enabled ports */
+ struct mutex lock; /* control access to rules */
enum vcap_type vtype; /* type of vcap */
int vinst; /* instance number within the same type */
int first_cid; /* first chain id in this vcap */
diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api_debugfs.c b/drivers/net/ethernet/microchip/vcap/vcap_api_debugfs.c
index 8e5b1cc24d80..534c51f2ec4f 100644
--- a/drivers/net/ethernet/microchip/vcap/vcap_api_debugfs.c
+++ b/drivers/net/ethernet/microchip/vcap/vcap_api_debugfs.c
@@ -618,6 +618,7 @@ static int vcap_show_admin(struct vcap_control *vctrl,
int ret = 0;

vcap_show_admin_info(vctrl, admin, out);
+ mutex_lock(&admin->lock);
list_for_each_entry(elem, &admin->rules, list) {
ri = vcap_dup_rule(elem);
if (IS_ERR(ri))
@@ -631,6 +632,7 @@ static int vcap_show_admin(struct vcap_control *vctrl,
free_rule:
vcap_free_rule((struct vcap_rule *)ri);
}
+ mutex_unlock(&admin->lock);
return ret;
}

--
2.38.1