From: "Matthew Wilcox (Oracle)" <wi...@infradead.org>
Rename this IDR to 'knodes' since that's what's being stored in it.
Use xa_alloc_cyclic() since that's what's being emulated in gen_new_kid().
Allow gen_new_kid() to return a "no space" indicator. Access to this
XArray is now under both the rtnl lock and the XArray spinlock.
Signed-off-by: Matthew Wilcox (Oracle) <wi...@infradead.org>
---
net/sched/cls_u32.c | 41 ++++++++++++++++++++---------------------
1 file changed, 20 insertions(+), 21 deletions(-)
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 18ef5f375976..46ddfd312952 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -38,7 +38,7 @@
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>
-#include <linux/idr.h>
+#include <linux/xarray.h>
struct tc_u_knode {
struct tc_u_knode __rcu *next;
@@ -72,7 +72,7 @@ struct tc_u_hnode {
u32 prio;
int refcnt;
unsigned int divisor;
- struct idr handle_idr;
+ struct xarray knodes;
bool is_root;
struct rcu_head rcu;
u32 flags;
@@ -366,7 +366,7 @@ static int u32_init(struct tcf_proto *tp)
root_ht->handle = tp_c ? gen_new_htid(tp_c, root_ht) : 0x80000000;
root_ht->prio = tp->prio;
root_ht->is_root = true;
- idr_init(&root_ht->handle_idr);
+ xa_init_flags(&root_ht->knodes, XA_FLAGS_ALLOC);
if (tp_c == NULL) {
tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
@@ -461,7 +461,7 @@ static int u32_delete_key(struct tcf_proto *tp, struct
tc_u_knode *key)
tp_c->knodes--;
tcf_unbind_filter(tp, &key->res);
- idr_remove(&ht->handle_idr, key->handle);
+ xa_erase(&ht->knodes, key->handle);
tcf_exts_get_net(&key->exts);
tcf_queue_work(&key->rwork,
u32_delete_key_freepf_work);
return 0;
@@ -585,7 +585,7 @@ static void u32_clear_hnode(struct tcf_proto *tp, struct
tc_u_hnode *ht,
tp_c->knodes--;
tcf_unbind_filter(tp, &n->res);
u32_remove_hw_knode(tp, n, extack);
- idr_remove(&ht->handle_idr, n->handle);
+ xa_erase(&ht->knodes, n->handle);
if (tcf_exts_get_net(&n->exts))
tcf_queue_work(&n->rwork,
u32_delete_key_freepf_work);
else
@@ -611,7 +611,6 @@ static int u32_destroy_hnode(struct tcf_proto *tp, struct
tc_u_hnode *ht,
hn = &phn->next, phn = rtnl_dereference(*hn)) {
if (phn == ht) {
u32_clear_hw_hnode(tp, ht, extack);
- idr_destroy(&ht->handle_idr);
xa_erase(&tp_c->ht_xa, ht->handle);
RCU_INIT_POINTER(*hn, ht->next);
kfree_rcu(ht, rcu);
@@ -687,15 +686,13 @@ static int u32_delete(struct tcf_proto *tp, void *arg,
bool *last,
static u32 gen_new_kid(struct tc_u_hnode *ht, u32 htid)
{
- u32 index = htid | 0x800;
- u32 max = htid | 0xFFF;
-
- if (idr_alloc_u32(&ht->handle_idr, NULL, &index, max, GFP_KERNEL)) {
- index = htid + 1;
- if (idr_alloc_u32(&ht->handle_idr, NULL, &index, max,
- GFP_KERNEL))
- index = max;
- }
+ u32 start = htid | 0x800;
+ u32 index;
+
+ if (xa_alloc_cyclic(&ht->knodes, &index, NULL,
+ XA_LIMIT(htid + 1, htid | 0xfff), &start,
+ GFP_KERNEL) < 0)
+ index = htid;
return index;
}
@@ -789,7 +786,7 @@ static void u32_replace_knode(struct tcf_proto *tp, struct
tc_u_common *tp_c,
if (pins->handle == n->handle)
break;
- idr_replace(&ht->handle_idr, n, n->handle);
+ xa_store(&ht->knodes, n->handle, n, 0);
RCU_INIT_POINTER(n->next, pins->next);
rcu_assign_pointer(*ins, n);
}
@@ -963,7 +960,7 @@ static int u32_change(struct net *net, struct sk_buff
*in_skb,
ht->divisor = divisor;
ht->handle = handle;
ht->prio = tp->prio;
- idr_init(&ht->handle_idr);
+ xa_init_flags(&ht->knodes, XA_FLAGS_ALLOC);
ht->flags = flags;
err = u32_replace_hw_hnode(tp, ht, flags, extack);
@@ -1008,12 +1005,14 @@ static int u32_change(struct net *net, struct sk_buff
*in_skb,
return -EINVAL;
}
handle = htid | TC_U32_NODE(handle);
- err = idr_alloc_u32(&ht->handle_idr, NULL, &handle, handle,
- GFP_KERNEL);
+ err = xa_insert(&ht->knodes, handle, NULL, GFP_KERNEL);
if (err)
return err;
- } else
+ } else {
handle = gen_new_kid(ht, htid);
+ if (handle == htid)
+ return -ENOBUFS;
+ }
if (tb[TCA_U32_SEL] == NULL) {
NL_SET_ERR_MSG_MOD(extack, "Selector not specified");
@@ -1108,7 +1107,7 @@ static int u32_change(struct net *net, struct sk_buff
*in_skb,
#endif
kfree(n);
erridr:
- idr_remove(&ht->handle_idr, handle);
+ xa_erase(&ht->knodes, handle);
return err;
}
--
2.23.0.rc1
