From 7cc05662682da4b0e0a4fdf3c3f190577803ae81 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 28 Jan 2015 18:04:53 +0100 Subject: [PATCH] net: remove sock_iocb The sock_iocb structure is allocate on stack for each read/write-like operation on sockets, and contains various fields of which only the embedded msghdr and sometimes a pointer to the scm_cookie is ever used. Get rid of the sock_iocb and put a msghdr directly on the stack and pass the scm_cookie explicitly to netlink_mmap_sendmsg. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller --- include/net/sock.h | 23 ------------- net/netlink/af_netlink.c | 28 ++++++--------- net/socket.c | 45 +++---------------------- net/unix/af_unix.c | 73 ++++++++++++++++------------------------ 4 files changed, 43 insertions(+), 126 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index 2210fec65669..15341499786c 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1374,29 +1374,6 @@ void sk_prot_clear_portaddr_nulls(struct sock *sk, int size); #define SOCK_BINDADDR_LOCK 4 #define SOCK_BINDPORT_LOCK 8 -/* sock_iocb: used to kick off async processing of socket ios */ -struct sock_iocb { - struct list_head list; - - int flags; - int size; - struct socket *sock; - struct sock *sk; - struct scm_cookie *scm; - struct msghdr *msg, async_msg; - struct kiocb *kiocb; -}; - -static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb) -{ - return (struct sock_iocb *)iocb->private; -} - -static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si) -{ - return si->kiocb; -} - struct socket_alloc { struct socket socket; struct inode vfs_inode; diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 2197af00673a..a36777b7cfb6 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -695,7 +695,7 @@ static void netlink_ring_setup_skb(struct sk_buff *skb, struct sock *sk, static int netlink_mmap_sendmsg(struct sock *sk, struct msghdr *msg, u32 dst_portid, u32 dst_group, - struct sock_iocb *siocb) + struct scm_cookie *scm) { struct netlink_sock *nlk = nlk_sk(sk); struct netlink_ring *ring; @@ -741,7 +741,7 @@ static int netlink_mmap_sendmsg(struct sock *sk, struct msghdr *msg, NETLINK_CB(skb).portid = nlk->portid; NETLINK_CB(skb).dst_group = dst_group; - NETLINK_CB(skb).creds = siocb->scm->creds; + NETLINK_CB(skb).creds = scm->creds; err = security_netlink_send(sk, skb); if (err) { @@ -820,7 +820,7 @@ static void netlink_ring_set_copied(struct sock *sk, struct sk_buff *skb) #define netlink_tx_is_mmaped(sk) false #define netlink_mmap sock_no_mmap #define netlink_poll datagram_poll -#define netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group, siocb) 0 +#define netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group, scm) 0 #endif /* CONFIG_NETLINK_MMAP */ static void netlink_skb_destructor(struct sk_buff *skb) @@ -2259,7 +2259,6 @@ static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, struct msghdr *msg, size_t len) { - struct sock_iocb *siocb = kiocb_to_siocb(kiocb); struct sock *sk = sock->sk; struct netlink_sock *nlk = nlk_sk(sk); DECLARE_SOCKADDR(struct sockaddr_nl *, addr, msg->msg_name); @@ -2273,10 +2272,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, if (msg->msg_flags&MSG_OOB) return -EOPNOTSUPP; - if (NULL == siocb->scm) - siocb->scm = &scm; - - err = scm_send(sock, msg, siocb->scm, true); + err = scm_send(sock, msg, &scm, true); if (err < 0) return err; @@ -2305,7 +2301,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, if (netlink_tx_is_mmaped(sk) && msg->msg_iter.iov->iov_base == NULL) { err = netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group, - siocb); + &scm); goto out; } @@ -2319,7 +2315,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, NETLINK_CB(skb).portid = nlk->portid; NETLINK_CB(skb).dst_group = dst_group; - NETLINK_CB(skb).creds = siocb->scm->creds; + NETLINK_CB(skb).creds = scm.creds; NETLINK_CB(skb).flags = netlink_skb_flags; err = -EFAULT; @@ -2341,7 +2337,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, err = netlink_unicast(sk, skb, dst_portid, msg->msg_flags&MSG_DONTWAIT); out: - scm_destroy(siocb->scm); + scm_destroy(&scm); return err; } @@ -2349,7 +2345,6 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, struct msghdr *msg, size_t len, int flags) { - struct sock_iocb *siocb = kiocb_to_siocb(kiocb); struct scm_cookie scm; struct sock *sk = sock->sk; struct netlink_sock *nlk = nlk_sk(sk); @@ -2412,11 +2407,8 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, if (nlk->flags & NETLINK_RECV_PKTINFO) netlink_cmsg_recv_pktinfo(msg, skb); - if (NULL == siocb->scm) { - memset(&scm, 0, sizeof(scm)); - siocb->scm = &scm; - } - siocb->scm->creds = *NETLINK_CREDS(skb); + memset(&scm, 0, sizeof(scm)); + scm.creds = *NETLINK_CREDS(skb); if (flags & MSG_TRUNC) copied = data_skb->len; @@ -2431,7 +2423,7 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, } } - scm_recv(sock, msg, siocb->scm, flags); + scm_recv(sock, msg, &scm, flags); out: netlink_rcv_wake(sk); return err ? : copied; diff --git a/net/socket.c b/net/socket.c index 3acd35f144d6..3326d67482ac 100644 --- a/net/socket.c +++ b/net/socket.c @@ -613,13 +613,6 @@ EXPORT_SYMBOL(__sock_tx_timestamp); static inline int __sock_sendmsg_nosec(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size) { - struct sock_iocb *si = kiocb_to_siocb(iocb); - - si->sock = sock; - si->scm = NULL; - si->msg = msg; - si->size = size; - return sock->ops->sendmsg(iocb, sock, msg, size); } @@ -635,11 +628,9 @@ static int do_sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t size, bool nosec) { struct kiocb iocb; - struct sock_iocb siocb; int ret; init_sync_kiocb(&iocb, NULL); - iocb.private = &siocb; ret = nosec ? __sock_sendmsg_nosec(&iocb, sock, msg, size) : __sock_sendmsg(&iocb, sock, msg, size); if (-EIOCBQUEUED == ret) @@ -756,14 +747,6 @@ EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops); static inline int __sock_recvmsg_nosec(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size, int flags) { - struct sock_iocb *si = kiocb_to_siocb(iocb); - - si->sock = sock; - si->scm = NULL; - si->msg = msg; - si->size = size; - si->flags = flags; - return sock->ops->recvmsg(iocb, sock, msg, size, flags); } @@ -779,11 +762,9 @@ int sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, int flags) { struct kiocb iocb; - struct sock_iocb siocb; int ret; init_sync_kiocb(&iocb, NULL); - iocb.private = &siocb; ret = __sock_recvmsg(&iocb, sock, msg, size, flags); if (-EIOCBQUEUED == ret) ret = wait_on_sync_kiocb(&iocb); @@ -795,11 +776,9 @@ static int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg, size_t size, int flags) { struct kiocb iocb; - struct sock_iocb siocb; int ret; init_sync_kiocb(&iocb, NULL); - iocb.private = &siocb; ret = __sock_recvmsg_nosec(&iocb, sock, msg, size, flags); if (-EIOCBQUEUED == ret) ret = wait_on_sync_kiocb(&iocb); @@ -866,14 +845,6 @@ static ssize_t sock_splice_read(struct file *file, loff_t *ppos, return sock->ops->splice_read(sock, ppos, pipe, len, flags); } -static struct sock_iocb *alloc_sock_iocb(struct kiocb *iocb, - struct sock_iocb *siocb) -{ - siocb->kiocb = iocb; - iocb->private = siocb; - return siocb; -} - static ssize_t do_sock_read(struct msghdr *msg, struct kiocb *iocb, struct file *file, const struct iovec *iov, unsigned long nr_segs) @@ -893,7 +864,7 @@ static ssize_t do_sock_read(struct msghdr *msg, struct kiocb *iocb, static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { - struct sock_iocb siocb, *x; + struct msghdr msg; if (pos != 0) return -ESPIPE; @@ -901,11 +872,7 @@ static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov, if (iocb->ki_nbytes == 0) /* Match SYS5 behaviour */ return 0; - - x = alloc_sock_iocb(iocb, &siocb); - if (!x) - return -ENOMEM; - return do_sock_read(&x->async_msg, iocb, iocb->ki_filp, iov, nr_segs); + return do_sock_read(&msg, iocb, iocb->ki_filp, iov, nr_segs); } static ssize_t do_sock_write(struct msghdr *msg, struct kiocb *iocb, @@ -929,16 +896,12 @@ static ssize_t do_sock_write(struct msghdr *msg, struct kiocb *iocb, static ssize_t sock_aio_write(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { - struct sock_iocb siocb, *x; + struct msghdr msg; if (pos != 0) return -ESPIPE; - x = alloc_sock_iocb(iocb, &siocb); - if (!x) - return -ENOMEM; - - return do_sock_write(&x->async_msg, iocb, iocb->ki_filp, iov, nr_segs); + return do_sock_write(&msg, iocb, iocb->ki_filp, iov, nr_segs); } /* diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 8e1b10274b02..526b6edab018 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -1445,7 +1445,6 @@ static void maybe_add_creds(struct sk_buff *skb, const struct socket *sock, static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, struct msghdr *msg, size_t len) { - struct sock_iocb *siocb = kiocb_to_siocb(kiocb); struct sock *sk = sock->sk; struct net *net = sock_net(sk); struct unix_sock *u = unix_sk(sk); @@ -1456,14 +1455,12 @@ static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, unsigned int hash; struct sk_buff *skb; long timeo; - struct scm_cookie tmp_scm; + struct scm_cookie scm; int max_level; int data_len = 0; - if (NULL == siocb->scm) - siocb->scm = &tmp_scm; wait_for_unix_gc(); - err = scm_send(sock, msg, siocb->scm, false); + err = scm_send(sock, msg, &scm, false); if (err < 0) return err; @@ -1507,11 +1504,11 @@ static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, if (skb == NULL) goto out; - err = unix_scm_to_skb(siocb->scm, skb, true); + err = unix_scm_to_skb(&scm, skb, true); if (err < 0) goto out_free; max_level = err + 1; - unix_get_secdata(siocb->scm, skb); + unix_get_secdata(&scm, skb); skb_put(skb, len - data_len); skb->data_len = data_len; @@ -1606,7 +1603,7 @@ restart: unix_state_unlock(other); other->sk_data_ready(other); sock_put(other); - scm_destroy(siocb->scm); + scm_destroy(&scm); return len; out_unlock: @@ -1616,7 +1613,7 @@ out_free: out: if (other) sock_put(other); - scm_destroy(siocb->scm); + scm_destroy(&scm); return err; } @@ -1628,21 +1625,18 @@ out: static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, struct msghdr *msg, size_t len) { - struct sock_iocb *siocb = kiocb_to_siocb(kiocb); struct sock *sk = sock->sk; struct sock *other = NULL; int err, size; struct sk_buff *skb; int sent = 0; - struct scm_cookie tmp_scm; + struct scm_cookie scm; bool fds_sent = false; int max_level; int data_len; - if (NULL == siocb->scm) - siocb->scm = &tmp_scm; wait_for_unix_gc(); - err = scm_send(sock, msg, siocb->scm, false); + err = scm_send(sock, msg, &scm, false); if (err < 0) return err; @@ -1683,7 +1677,7 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, goto out_err; /* Only send the fds in the first buffer */ - err = unix_scm_to_skb(siocb->scm, skb, !fds_sent); + err = unix_scm_to_skb(&scm, skb, !fds_sent); if (err < 0) { kfree_skb(skb); goto out_err; @@ -1715,8 +1709,7 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, sent += size; } - scm_destroy(siocb->scm); - siocb->scm = NULL; + scm_destroy(&scm); return sent; @@ -1728,8 +1721,7 @@ pipe_err: send_sig(SIGPIPE, current, 0); err = -EPIPE; out_err: - scm_destroy(siocb->scm); - siocb->scm = NULL; + scm_destroy(&scm); return sent ? : err; } @@ -1778,8 +1770,7 @@ static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size, int flags) { - struct sock_iocb *siocb = kiocb_to_siocb(iocb); - struct scm_cookie tmp_scm; + struct scm_cookie scm; struct sock *sk = sock->sk; struct unix_sock *u = unix_sk(sk); int noblock = flags & MSG_DONTWAIT; @@ -1831,16 +1822,14 @@ static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock, if (sock_flag(sk, SOCK_RCVTSTAMP)) __sock_recv_timestamp(msg, sk, skb); - if (!siocb->scm) { - siocb->scm = &tmp_scm; - memset(&tmp_scm, 0, sizeof(tmp_scm)); - } - scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid); - unix_set_secdata(siocb->scm, skb); + memset(&scm, 0, sizeof(scm)); + + scm_set_cred(&scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid); + unix_set_secdata(&scm, skb); if (!(flags & MSG_PEEK)) { if (UNIXCB(skb).fp) - unix_detach_fds(siocb->scm, skb); + unix_detach_fds(&scm, skb); sk_peek_offset_bwd(sk, skb->len); } else { @@ -1860,11 +1849,11 @@ static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock, sk_peek_offset_fwd(sk, size); if (UNIXCB(skb).fp) - siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); + scm.fp = scm_fp_dup(UNIXCB(skb).fp); } err = (flags & MSG_TRUNC) ? skb->len - skip : size; - scm_recv(sock, msg, siocb->scm, flags); + scm_recv(sock, msg, &scm, flags); out_free: skb_free_datagram(sk, skb); @@ -1915,8 +1904,7 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size, int flags) { - struct sock_iocb *siocb = kiocb_to_siocb(iocb); - struct scm_cookie tmp_scm; + struct scm_cookie scm; struct sock *sk = sock->sk; struct unix_sock *u = unix_sk(sk); DECLARE_SOCKADDR(struct sockaddr_un *, sunaddr, msg->msg_name); @@ -1943,10 +1931,7 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock, * while sleeps in memcpy_tomsg */ - if (!siocb->scm) { - siocb->scm = &tmp_scm; - memset(&tmp_scm, 0, sizeof(tmp_scm)); - } + memset(&scm, 0, sizeof(scm)); err = mutex_lock_interruptible(&u->readlock); if (unlikely(err)) { @@ -2012,13 +1997,13 @@ again: if (check_creds) { /* Never glue messages from different writers */ - if ((UNIXCB(skb).pid != siocb->scm->pid) || - !uid_eq(UNIXCB(skb).uid, siocb->scm->creds.uid) || - !gid_eq(UNIXCB(skb).gid, siocb->scm->creds.gid)) + if ((UNIXCB(skb).pid != scm.pid) || + !uid_eq(UNIXCB(skb).uid, scm.creds.uid) || + !gid_eq(UNIXCB(skb).gid, scm.creds.gid)) break; } else if (test_bit(SOCK_PASSCRED, &sock->flags)) { /* Copy credentials */ - scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid); + scm_set_cred(&scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid); check_creds = 1; } @@ -2045,7 +2030,7 @@ again: sk_peek_offset_bwd(sk, chunk); if (UNIXCB(skb).fp) - unix_detach_fds(siocb->scm, skb); + unix_detach_fds(&scm, skb); if (unix_skb_len(skb)) break; @@ -2053,13 +2038,13 @@ again: skb_unlink(skb, &sk->sk_receive_queue); consume_skb(skb); - if (siocb->scm->fp) + if (scm.fp) break; } else { /* It is questionable, see note in unix_dgram_recvmsg. */ if (UNIXCB(skb).fp) - siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); + scm.fp = scm_fp_dup(UNIXCB(skb).fp); sk_peek_offset_fwd(sk, chunk); @@ -2068,7 +2053,7 @@ again: } while (size); mutex_unlock(&u->readlock); - scm_recv(sock, msg, siocb->scm, flags); + scm_recv(sock, msg, &scm, flags); out: return copied ? : err; } -- 2.20.1