[PATCH 06/15] ksocknal_lib_send_kiov(): sendmsg doesn't bugger iovec...

[Oleg Drokin]

From: Al Viro <v...@zeniv.linux.org.uk>

Signed-off-by: Al Viro <v...@zeniv.linux.org.uk>
---
 .../lustre/lnet/klnds/socklnd/socklnd_lib.c        | 29 ++++------------------
 1 file changed, 5 insertions(+), 24 deletions(-)

diff --git a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c 
b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c
index 8eb4a68..6c95e98 100644
--- a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c
+++ b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c
@@ -106,10 +106,6 @@ ksocknal_lib_send_kiov(struct ksock_conn *conn, struct 
ksock_tx *tx)
        /* Not NOOP message */
        LASSERT(tx->tx_lnetmsg);
 
-       /*
-        * NB we can't trust socket ops to either consume our iovs
-        * or leave them alone.
-        */
        if (tx->tx_msg.ksm_zc_cookies[0]) {
                /* Zero copy is enabled */
                struct sock *sk = sock->sk;
@@ -132,34 +128,19 @@ ksocknal_lib_send_kiov(struct ksock_conn *conn, struct 
ksock_tx *tx)
                        rc = tcp_sendpage(sk, page, offset, fragsize, msgflg);
                }
        } else {
-#if SOCKNAL_SINGLE_FRAG_TX || !SOCKNAL_RISK_KMAP_DEADLOCK
-               struct kvec scratch;
-               struct kvec *scratchiov = &scratch;
-               unsigned int niov = 1;
-#else
-#ifdef CONFIG_HIGHMEM
-#warning "XXX risk of kmap deadlock on multiple frags..."
-#endif
-               struct kvec *scratchiov = conn->ksnc_scheduler->kss_scratch_iov;
-               unsigned int niov = tx->tx_nkiov;
-#endif
                struct msghdr msg = {.msg_flags = MSG_DONTWAIT};
                int i;
 
-               for (nob = i = 0; i < niov; i++) {
-                       scratchiov[i].iov_base = kmap(kiov[i].bv_page) +
-                                                kiov[i].bv_offset;
-                       nob += scratchiov[i].iov_len = kiov[i].bv_len;
-               }
+               for (nob = i = 0; i < tx->tx_nkiov; i++)
+                       nob += kiov[i].bv_len;
 
                if (!list_empty(&conn->ksnc_tx_queue) ||
                    nob < tx->tx_resid)
                        msg.msg_flags |= MSG_MORE;
 
-               rc = kernel_sendmsg(sock, &msg, (struct kvec *)scratchiov, 
niov, nob);
-
-               for (i = 0; i < niov; i++)
-                       kunmap(kiov[i].bv_page);
+               iov_iter_bvec(&msg.msg_iter, WRITE | ITER_BVEC,
+                             kiov, tx->tx_nkiov, nob);
+               rc = sock_sendmsg(sock, &msg);
        }
        return rc;
 }
-- 
2.7.4