Skip to content

Commit

Permalink
net: sched: flower: track rtnl lock state
Browse files Browse the repository at this point in the history 
Use 'rtnl_held' flag to track if caller holds rtnl lock. Propagate the flag
to internal functions that need to know rtnl lock state. Take rtnl lock
before calling tcf APIs that require it (hw offload, bind filter, etc.).

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
Vlad Buslov authored and David S. Miller committed Mar 21, 2019
1 parent 3d81e71 commit c24e43d
Showing 1 changed file with 56 additions and 26 deletions.
82 changes: 56 additions & 26 deletions net/sched/cls_flower.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -374,11 +374,14 @@ static void fl_destroy_filter_work(struct work_struct *work)
}

static void fl_hw_destroy_filter(struct tcf_proto *tp, struct cls_fl_filter *f,
struct netlink_ext_ack *extack)
bool rtnl_held, struct netlink_ext_ack *extack)
{
struct tc_cls_flower_offload cls_flower = {};
struct tcf_block *block = tp->chain->block;

if (!rtnl_held)
rtnl_lock();

tc_cls_common_offload_init(&cls_flower.common, tp, f->flags, extack);
cls_flower.command = TC_CLSFLOWER_DESTROY;
cls_flower.cookie = (unsigned long) f;
Expand All @@ -387,20 +390,28 @@ static void fl_hw_destroy_filter(struct tcf_proto *tp, struct cls_fl_filter *f,
spin_lock(&tp->lock);
tcf_block_offload_dec(block, &f->flags);
spin_unlock(&tp->lock);

if (!rtnl_held)
rtnl_unlock();
}

static int fl_hw_replace_filter(struct tcf_proto *tp,
struct cls_fl_filter *f,
struct cls_fl_filter *f, bool rtnl_held,
struct netlink_ext_ack *extack)
{
struct tc_cls_flower_offload cls_flower = {};
struct tcf_block *block = tp->chain->block;
bool skip_sw = tc_skip_sw(f->flags);
int err;
int err = 0;

if (!rtnl_held)
rtnl_lock();

cls_flower.rule = flow_rule_alloc(tcf_exts_num_actions(&f->exts));
if (!cls_flower.rule)
return -ENOMEM;
if (!cls_flower.rule) {
err = -ENOMEM;
goto errout;
}

tc_cls_common_offload_init(&cls_flower.common, tp, f->flags, extack);
cls_flower.command = TC_CLSFLOWER_REPLACE;
Expand All @@ -413,37 +424,48 @@ static int fl_hw_replace_filter(struct tcf_proto *tp,
err = tc_setup_flow_action(&cls_flower.rule->action, &f->exts);
if (err) {
kfree(cls_flower.rule);
if (skip_sw) {
if (skip_sw)
NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
return err;
}
return 0;
else
err = 0;
goto errout;
}

err = tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, skip_sw);
kfree(cls_flower.rule);

if (err < 0) {
fl_hw_destroy_filter(tp, f, NULL);
return err;
fl_hw_destroy_filter(tp, f, true, NULL);
goto errout;
} else if (err > 0) {
f->in_hw_count = err;
err = 0;
spin_lock(&tp->lock);
tcf_block_offload_inc(block, &f->flags);
spin_unlock(&tp->lock);
}

if (skip_sw && !(f->flags & TCA_CLS_FLAGS_IN_HW))
return -EINVAL;
if (skip_sw && !(f->flags & TCA_CLS_FLAGS_IN_HW)) {
err = -EINVAL;
goto errout;
}

return 0;
errout:
if (!rtnl_held)
rtnl_unlock();

return err;
}

static void fl_hw_update_stats(struct tcf_proto *tp, struct cls_fl_filter *f)
static void fl_hw_update_stats(struct tcf_proto *tp, struct cls_fl_filter *f,
bool rtnl_held)
{
struct tc_cls_flower_offload cls_flower = {};
struct tcf_block *block = tp->chain->block;

if (!rtnl_held)
rtnl_lock();

tc_cls_common_offload_init(&cls_flower.common, tp, f->flags, NULL);
cls_flower.command = TC_CLSFLOWER_STATS;
cls_flower.cookie = (unsigned long) f;
Expand All @@ -454,6 +476,9 @@ static void fl_hw_update_stats(struct tcf_proto *tp, struct cls_fl_filter *f)
tcf_exts_stats_update(&f->exts, cls_flower.stats.bytes,
cls_flower.stats.pkts,
cls_flower.stats.lastused);

if (!rtnl_held)
rtnl_unlock();
}

static struct cls_fl_head *fl_head_dereference(struct tcf_proto *tp)
Expand Down Expand Up @@ -511,7 +536,8 @@ static struct cls_fl_filter *fl_get_next_filter(struct tcf_proto *tp,
}

static int __fl_delete(struct tcf_proto *tp, struct cls_fl_filter *f,
bool *last, struct netlink_ext_ack *extack)
bool *last, bool rtnl_held,
struct netlink_ext_ack *extack)
{
struct cls_fl_head *head = fl_head_dereference(tp);
bool async = tcf_exts_get_net(&f->exts);
Expand All @@ -533,7 +559,7 @@ static int __fl_delete(struct tcf_proto *tp, struct cls_fl_filter *f,

*last = fl_mask_put(head, f->mask, async);
if (!tc_skip_hw(f->flags))
fl_hw_destroy_filter(tp, f, extack);
fl_hw_destroy_filter(tp, f, rtnl_held, extack);
tcf_unbind_filter(tp, &f->res);
__fl_put(f);

Expand Down Expand Up @@ -561,7 +587,7 @@ static void fl_destroy(struct tcf_proto *tp, bool rtnl_held,

list_for_each_entry_safe(mask, next_mask, &head->masks, list) {
list_for_each_entry_safe(f, next, &mask->filters, list) {
__fl_delete(tp, f, &last, extack);
__fl_delete(tp, f, &last, rtnl_held, extack);
if (last)
break;
}
Expand Down Expand Up @@ -1401,19 +1427,23 @@ static int fl_set_parms(struct net *net, struct tcf_proto *tp,
struct cls_fl_filter *f, struct fl_flow_mask *mask,
unsigned long base, struct nlattr **tb,
struct nlattr *est, bool ovr,
struct fl_flow_tmplt *tmplt,
struct fl_flow_tmplt *tmplt, bool rtnl_held,
struct netlink_ext_ack *extack)
{
int err;

err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr, true,
err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr, rtnl_held,
extack);
if (err < 0)
return err;

if (tb[TCA_FLOWER_CLASSID]) {
f->res.classid = nla_get_u32(tb[TCA_FLOWER_CLASSID]);
if (!rtnl_held)
rtnl_lock();
tcf_bind_filter(tp, &f->res, base);
if (!rtnl_held)
rtnl_unlock();
}

err = fl_set_key(net, tb, &f->key, &mask->key, extack);
Expand Down Expand Up @@ -1492,7 +1522,7 @@ static int fl_change(struct net *net, struct sk_buff *in_skb,
}

err = fl_set_parms(net, tp, fnew, mask, base, tb, tca[TCA_RATE], ovr,
tp->chain->tmplt_priv, extack);
tp->chain->tmplt_priv, rtnl_held, extack);
if (err)
goto errout;

Expand All @@ -1501,7 +1531,7 @@ static int fl_change(struct net *net, struct sk_buff *in_skb,
goto errout;

if (!tc_skip_hw(fnew->flags)) {
err = fl_hw_replace_filter(tp, fnew, extack);
err = fl_hw_replace_filter(tp, fnew, rtnl_held, extack);
if (err)
goto errout_mask;
}
Expand Down Expand Up @@ -1545,7 +1575,7 @@ static int fl_change(struct net *net, struct sk_buff *in_skb,

fl_mask_put(head, fold->mask, true);
if (!tc_skip_hw(fold->flags))
fl_hw_destroy_filter(tp, fold, NULL);
fl_hw_destroy_filter(tp, fold, rtnl_held, NULL);
tcf_unbind_filter(tp, &fold->res);
tcf_exts_get_net(&fold->exts);
/* Caller holds reference to fold, so refcnt is always > 0
Expand Down Expand Up @@ -1602,7 +1632,7 @@ static int fl_change(struct net *net, struct sk_buff *in_skb,
errout_hw:
spin_unlock(&tp->lock);
if (!tc_skip_hw(fnew->flags))
fl_hw_destroy_filter(tp, fnew, NULL);
fl_hw_destroy_filter(tp, fnew, rtnl_held, NULL);
errout_mask:
fl_mask_put(head, fnew->mask, true);
errout:
Expand All @@ -1626,7 +1656,7 @@ static int fl_delete(struct tcf_proto *tp, void *arg, bool *last,
bool last_on_mask;
int err = 0;

err = __fl_delete(tp, f, &last_on_mask, extack);
err = __fl_delete(tp, f, &last_on_mask, rtnl_held, extack);
*last = list_empty(&head->masks);
__fl_put(f);

Expand Down Expand Up @@ -2270,7 +2300,7 @@ static int fl_dump(struct net *net, struct tcf_proto *tp, void *fh,
spin_unlock(&tp->lock);

if (!skip_hw)
fl_hw_update_stats(tp, f);
fl_hw_update_stats(tp, f, rtnl_held);

if (nla_put_u32(skb, TCA_FLOWER_IN_HW_COUNT, f->in_hw_count))
goto nla_put_failure;
Expand Down

0 comments on commit c24e43d

Please sign in to comment.