@@ -411,6 +411,7 @@ struct ubuf_info {
struct {
u32 id;
u16 len;
+ u16 kbytelen;
};
};
atomic_t refcnt;
@@ -974,6 +974,7 @@ struct ubuf_info *sock_zerocopy_alloc(struct sock *sk, size_t size)
uarg->callback = sock_zerocopy_callback;
uarg->id = ((u32)atomic_inc_return(&sk->sk_zckey)) - 1;
uarg->len = 1;
+ uarg->kbytelen = min_t(size_t, DIV_ROUND_UP(size, 1024u), USHRT_MAX);
atomic_set(&uarg->refcnt, 0);
sock_hold(sk);
@@ -990,6 +991,8 @@ struct ubuf_info *sock_zerocopy_realloc(struct sock *sk, size_t size,
struct ubuf_info *uarg)
{
if (uarg) {
+ const size_t limit_kb = 512; /* consider a sysctl */
+ size_t kbytelen;
u32 next;
/* realloc only when socket is locked (TCP, UDP cork),
@@ -997,8 +1000,13 @@ struct ubuf_info *sock_zerocopy_realloc(struct sock *sk, size_t size,
*/
BUG_ON(!sock_owned_by_user(sk));
+ kbytelen = uarg->kbytelen + DIV_ROUND_UP(size, 1024u);
+ if (unlikely(kbytelen > limit_kb))
+ goto new_alloc;
+ uarg->kbytelen = kbytelen;
+
if (unlikely(uarg->len == USHRT_MAX - 1))
- return NULL;
+ goto new_alloc;
next = (u32)atomic_read(&sk->sk_zckey);
if ((u32)(uarg->id + uarg->len) == next) {
@@ -1010,6 +1018,7 @@ struct ubuf_info *sock_zerocopy_realloc(struct sock *sk, size_t size,
}
}
+new_alloc:
return sock_zerocopy_alloc(sk, size);
}
EXPORT_SYMBOL_GPL(sock_zerocopy_realloc);