rhashtable: accept GFP flags in rhashtable_walk_init
In certain cases, the 802.11 mesh pathtable code wants to
iterate over all of the entries in the forwarding table from
the receive path, which is inside an RCU read-side critical
section. Enable walks inside atomic sections by allowing
GFP_ATOMIC allocations for the walker state.
Change all existing callsites to pass in GFP_KERNEL.
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Bob Copeland <me@bobcopeland.com>
[also adjust gfs2/glock.c and rhashtable tests]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 6539131..4b73bd1 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1913,7 +1913,7 @@
if (seq->buf)
seq->size = GFS2_SEQ_GOODSIZE;
gi->gl = NULL;
- ret = rhashtable_walk_init(&gl_hash_table, &gi->hti);
+ ret = rhashtable_walk_init(&gl_hash_table, &gi->hti, GFP_KERNEL);
}
return ret;
}
@@ -1941,7 +1941,7 @@
if (seq->buf)
seq->size = GFS2_SEQ_GOODSIZE;
gi->gl = NULL;
- ret = rhashtable_walk_init(&gl_hash_table, &gi->hti);
+ ret = rhashtable_walk_init(&gl_hash_table, &gi->hti, GFP_KERNEL);
}
return ret;
}
diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h
index 63bd760..3eef080 100644
--- a/include/linux/rhashtable.h
+++ b/include/linux/rhashtable.h
@@ -346,7 +346,8 @@
struct bucket_table *old_tbl);
int rhashtable_insert_rehash(struct rhashtable *ht, struct bucket_table *tbl);
-int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter);
+int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter,
+ gfp_t gfp);
void rhashtable_walk_exit(struct rhashtable_iter *iter);
int rhashtable_walk_start(struct rhashtable_iter *iter) __acquires(RCU);
void *rhashtable_walk_next(struct rhashtable_iter *iter);
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index cc80870..5d845ff 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -487,6 +487,7 @@
* rhashtable_walk_init - Initialise an iterator
* @ht: Table to walk over
* @iter: Hash table Iterator
+ * @gfp: GFP flags for allocations
*
* This function prepares a hash table walk.
*
@@ -504,14 +505,15 @@
* You must call rhashtable_walk_exit if this function returns
* successfully.
*/
-int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter)
+int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter,
+ gfp_t gfp)
{
iter->ht = ht;
iter->p = NULL;
iter->slot = 0;
iter->skip = 0;
- iter->walker = kmalloc(sizeof(*iter->walker), GFP_KERNEL);
+ iter->walker = kmalloc(sizeof(*iter->walker), gfp);
if (!iter->walker)
return -ENOMEM;
diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c
index 270bf72..297fdb5 100644
--- a/lib/test_rhashtable.c
+++ b/lib/test_rhashtable.c
@@ -143,7 +143,7 @@
struct rhashtable_iter hti;
struct rhash_head *pos;
- err = rhashtable_walk_init(ht, &hti);
+ err = rhashtable_walk_init(ht, &hti, GFP_KERNEL);
if (err) {
pr_warn("Test failed: allocation error");
return;
diff --git a/net/ipv6/ila/ila_xlat.c b/net/ipv6/ila/ila_xlat.c
index 295ca29..0b03533 100644
--- a/net/ipv6/ila/ila_xlat.c
+++ b/net/ipv6/ila/ila_xlat.c
@@ -501,7 +501,8 @@
struct ila_net *ilan = net_generic(net, ila_net_id);
struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args;
- return rhashtable_walk_init(&ilan->rhash_table, &iter->rhiter);
+ return rhashtable_walk_init(&ilan->rhash_table, &iter->rhiter,
+ GFP_KERNEL);
}
static int ila_nl_dump_done(struct netlink_callback *cb)
diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c
index 3f9d45d..6fa0165 100644
--- a/net/netfilter/nft_hash.c
+++ b/net/netfilter/nft_hash.c
@@ -192,7 +192,7 @@
u8 genmask = nft_genmask_cur(read_pnet(&set->pnet));
int err;
- err = rhashtable_walk_init(&priv->ht, &hti);
+ err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
iter->err = err;
if (err)
return;
@@ -248,7 +248,7 @@
priv = container_of(work, struct nft_hash, gc_work.work);
set = nft_set_container_of(priv);
- err = rhashtable_walk_init(&priv->ht, &hti);
+ err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
if (err)
goto schedule;
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 215fc08..0f16bf63 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -2343,7 +2343,8 @@
{
int err;
- err = rhashtable_walk_init(&nl_table[iter->link].hash, &iter->hti);
+ err = rhashtable_walk_init(&nl_table[iter->link].hash, &iter->hti,
+ GFP_KERNEL);
if (err) {
iter->link = MAX_LINKS;
return err;
diff --git a/net/sctp/proc.c b/net/sctp/proc.c
index 5cfac8d..6d45d53 100644
--- a/net/sctp/proc.c
+++ b/net/sctp/proc.c
@@ -319,7 +319,8 @@
struct sctp_ht_iter *iter = seq->private;
int err;
- err = rhashtable_walk_init(&sctp_transport_hashtable, &iter->hti);
+ err = rhashtable_walk_init(&sctp_transport_hashtable, &iter->hti,
+ GFP_KERNEL);
if (err)
return err;
