diff options
Diffstat (limited to 'net/core/sock.c')
| -rw-r--r-- | net/core/sock.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/net/core/sock.c b/net/core/sock.c index 512e629f9780..0ecb8590e043 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -947,6 +947,53 @@ void sock_set_mark(struct sock *sk, u32 val) } EXPORT_SYMBOL(sock_set_mark); +static void sock_release_reserved_memory(struct sock *sk, int bytes) +{ + /* Round down bytes to multiple of pages */ + bytes &= ~(SK_MEM_QUANTUM - 1); + + WARN_ON(bytes > sk->sk_reserved_mem); + sk->sk_reserved_mem -= bytes; + sk_mem_reclaim(sk); +} + +static int sock_reserve_memory(struct sock *sk, int bytes) +{ + long allocated; + bool charged; + int pages; + + if (!mem_cgroup_sockets_enabled || !sk->sk_memcg) + return -EOPNOTSUPP; + + if (!bytes) + return 0; + + pages = sk_mem_pages(bytes); + + /* pre-charge to memcg */ + charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages, + GFP_KERNEL | __GFP_RETRY_MAYFAIL); + if (!charged) + return -ENOMEM; + + /* pre-charge to forward_alloc */ + allocated = sk_memory_allocated_add(sk, pages); + /* If the system goes into memory pressure with this + * precharge, give up and return error. + */ + if (allocated > sk_prot_mem_limits(sk, 1)) { + sk_memory_allocated_sub(sk, pages); + mem_cgroup_uncharge_skmem(sk->sk_memcg, pages); + return -ENOMEM; + } + sk->sk_forward_alloc += pages << SK_MEM_QUANTUM_SHIFT; + + sk->sk_reserved_mem += pages << SK_MEM_QUANTUM_SHIFT; + + return 0; +} + /* * This is meant for all protocols to use and covers goings on * at the socket level. Everything here is generic. @@ -1367,6 +1414,23 @@ set_sndbuf: ~SOCK_BUF_LOCK_MASK); break; + case SO_RESERVE_MEM: + { + int delta; + + if (val < 0) { + ret = -EINVAL; + break; + } + + delta = val - sk->sk_reserved_mem; + if (delta < 0) + sock_release_reserved_memory(sk, -delta); + else + ret = sock_reserve_memory(sk, delta); + break; + } + default: ret = -ENOPROTOOPT; break; @@ -1733,6 +1797,10 @@ int sock_getsockopt(struct socket *sock, int level, int optname, v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK; break; + case SO_RESERVE_MEM: + v.val = sk->sk_reserved_mem; + break; + default: /* We implement the SO_SNDLOWAT etc to not be settable * (1003.1g 7). @@ -2045,6 +2113,7 @@ struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) newsk->sk_dst_pending_confirm = 0; newsk->sk_wmem_queued = 0; newsk->sk_forward_alloc = 0; + newsk->sk_reserved_mem = 0; atomic_set(&newsk->sk_drops, 0); newsk->sk_send_head = NULL; newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; |