iov_iter: Separate type from direction and use accessor functions

In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>

11 files changed, 17 insertions, 17 deletions

diff --git a/net/9p/client.c b/net/9p/client.c
index deae53a7dffc..a9cd1401bd09 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -2070,7 +2070,7 @@ int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
         struct kvec kv = {.iov_base = data, .iov_len = count};
         struct iov_iter to;
 
-        iov_iter_kvec(&to, READ | ITER_KVEC, &kv, 1, count);
+        iov_iter_kvec(&to, READ, &kv, 1, count);
 
         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
                                 fid->fid, (unsigned long long) offset, count);
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 4e2576fc0c59..828e87fe8027 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -467,7 +467,7 @@ static int send_pkt(struct l2cap_chan *chan, struct sk_buff *skb,
         iv.iov_len = skb->len;
 
         memset(&msg, 0, sizeof(msg));
-        iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iv, 1, skb->len);
+        iov_iter_kvec(&msg.msg_iter, WRITE, &iv, 1, skb->len);
 
         err = l2cap_chan_send(chan, &msg, skb->len);
         if (err > 0) {
diff --git a/net/bluetooth/a2mp.c b/net/bluetooth/a2mp.c
index 51c2cf2d8923..58fc6333d412 100644
--- a/net/bluetooth/a2mp.c
+++ b/net/bluetooth/a2mp.c
@@ -63,7 +63,7 @@ static void a2mp_send(struct amp_mgr *mgr, u8 code, u8 ident, u16 len, void *dat
 
         memset(&msg, 0, sizeof(msg));
 
-        iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iv, 1, total_len);
+        iov_iter_kvec(&msg.msg_iter, WRITE, &iv, 1, total_len);
 
         l2cap_chan_send(chan, &msg, total_len);
 
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index a1c1b7e8a45c..c822e626761b 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -622,7 +622,7 @@ static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
 
         memset(&msg, 0, sizeof(msg));
 
-        iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
+        iov_iter_kvec(&msg.msg_iter, WRITE, iv, 2, 1 + len);
 
         l2cap_chan_send(chan, &msg, 1 + len);
 
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 0a187196aeed..e493ff77b378 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -526,7 +526,7 @@ static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len)
         if (!buf)
                 msg.msg_flags |= MSG_TRUNC;
 
-        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, len);
+        iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, len);
         r = sock_recvmsg(sock, &msg, msg.msg_flags);
         if (r == -EAGAIN)
                 r = 0;
@@ -545,7 +545,7 @@ static int ceph_tcp_recvpage(struct socket *sock, struct page *page,
         int r;
 
         BUG_ON(page_offset + length > PAGE_SIZE);
-        iov_iter_bvec(&msg.msg_iter, READ | ITER_BVEC, &bvec, 1, length);
+        iov_iter_bvec(&msg.msg_iter, READ, &bvec, 1, length);
         r = sock_recvmsg(sock, &msg, msg.msg_flags);
         if (r == -EAGAIN)
                 r = 0;
@@ -607,7 +607,7 @@ static int ceph_tcp_sendpage(struct socket *sock, struct page *page,
         else
                 msg.msg_flags |= MSG_EOR;  /* superfluous, but what the hell */
 
-        iov_iter_bvec(&msg.msg_iter, WRITE | ITER_BVEC, &bvec, 1, size);
+        iov_iter_bvec(&msg.msg_iter, WRITE, &bvec, 1, size);
         ret = sock_sendmsg(sock, &msg);
         if (ret == -EAGAIN)
                 ret = 0;
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index d4020c5e831d..2526be6b3d90 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -1616,7 +1616,7 @@ ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
         EnterFunction(7);
 
         /* Receive a packet */
-        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, buflen);
+        iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, buflen);
         len = sock_recvmsg(sock, &msg, MSG_DONTWAIT);
         if (len < 0)
                 return len;
diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 52241d679cc9..89c3a8c7859a 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -286,7 +286,7 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
          */
         krflags = MSG_PEEK | MSG_WAITALL;
         smc->clcsock->sk->sk_rcvtimeo = CLC_WAIT_TIME;
-        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &vec, 1,
+        iov_iter_kvec(&msg.msg_iter, READ, &vec, 1,
                         sizeof(struct smc_clc_msg_hdr));
         len = sock_recvmsg(smc->clcsock, &msg, krflags);
         if (signal_pending(current)) {
@@ -325,7 +325,7 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
 
         /* receive the complete CLC message */
         memset(&msg, 0, sizeof(struct msghdr));
-        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &vec, 1, datlen);
+        iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, datlen);
         krflags = MSG_WAITALL;
         len = sock_recvmsg(smc->clcsock, &msg, krflags);
         if (len < datlen || !smc_clc_msg_hdr_valid(clcm)) {
diff --git a/net/socket.c b/net/socket.c
index b68801c7d0ab..fae408abea54 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -635,7 +635,7 @@ EXPORT_SYMBOL(sock_sendmsg);
 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
                    struct kvec *vec, size_t num, size_t size)
 {
-        iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, vec, num, size);
+        iov_iter_kvec(&msg->msg_iter, WRITE, vec, num, size);
         return sock_sendmsg(sock, msg);
 }
 EXPORT_SYMBOL(kernel_sendmsg);
@@ -648,7 +648,7 @@ int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
         if (!sock->ops->sendmsg_locked)
                 return sock_no_sendmsg_locked(sk, msg, size);
 
-        iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, vec, num, size);
+        iov_iter_kvec(&msg->msg_iter, WRITE, vec, num, size);
 
         return sock->ops->sendmsg_locked(sk, msg, msg_data_left(msg));
 }
@@ -823,7 +823,7 @@ int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
         mm_segment_t oldfs = get_fs();
         int result;
 
-        iov_iter_kvec(&msg->msg_iter, READ | ITER_KVEC, vec, num, size);
+        iov_iter_kvec(&msg->msg_iter, READ, vec, num, size);
         set_fs(KERNEL_DS);
         result = sock_recvmsg(sock, msg, flags);
         set_fs(oldfs);
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 5445145e639c..0b46ec0bf74e 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -338,7 +338,7 @@ static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
         rqstp->rq_xprt_hlen = 0;
 
         clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
-        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, iov, nr, buflen);
+        iov_iter_kvec(&msg.msg_iter, READ, iov, nr, buflen);
         len = sock_recvmsg(svsk->sk_sock, &msg, msg.msg_flags);
         /* If we read a full record, then assume there may be more
          * data to read (stream based sockets only!)
diff --git a/net/tipc/topsrv.c b/net/tipc/topsrv.c
index d8956f7daac4..afa02eeec403 100644
--- a/net/tipc/topsrv.c
+++ b/net/tipc/topsrv.c
@@ -394,7 +394,7 @@ static int tipc_conn_rcv_from_sock(struct tipc_conn *con)
         iov.iov_base = &s;
         iov.iov_len = sizeof(s);
         msg.msg_name = NULL;
-        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, iov.iov_len);
+        iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, iov.iov_len);
         ret = sock_recvmsg(con->sock, &msg, MSG_DONTWAIT);
         if (ret == -EWOULDBLOCK)
                 return -EWOULDBLOCK;
diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 276edbc04f38..d753e362d2d9 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -489,7 +489,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
 
         iov.iov_base = kaddr + offset;
         iov.iov_len = size;
-        iov_iter_kvec(&msg_iter, WRITE | ITER_KVEC, &iov, 1, size);
+        iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);
         rc = tls_push_data(sk, &msg_iter, size,
                            flags, TLS_RECORD_TYPE_DATA);
         kunmap(page);
@@ -538,7 +538,7 @@ static int tls_device_push_pending_record(struct sock *sk, int flags)
 {
         struct iov_iter msg_iter;
 
-        iov_iter_kvec(&msg_iter, WRITE | ITER_KVEC, NULL, 0, 0);
+        iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0);
         return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA);
 }