[PATCH net-next v5 11/16] scsi: iscsi_tcp: Use sendmsg(MSG_SPLICE_PAGES) rather than sendpage
From: David Howells <dhowells@redhat.com>
Date: 2023-06-23 22:57:25
Also in:
linux-mm, linux-scsi, lkml, target-devel
Subsystem:
iscsi, scsi subsystem, the rest · Maintainers:
Lee Duncan, Chris Leech, Mike Christie, "James E.J. Bottomley", "Martin K. Petersen", Linus Torvalds
Use sendmsg() with MSG_SPLICE_PAGES rather than sendpage. This allows
multiple pages and multipage folios to be passed through.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
cc: Lee Duncan <lduncan@suse.com>
cc: Chris Leech <cleech@redhat.com>
cc: "James E.J. Bottomley" <redacted>
cc: "Martin K. Petersen" <martin.petersen@oracle.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: open-iscsi@googlegroups.com
cc: linux-scsi@vger.kernel.org
cc: target-devel@vger.kernel.org
cc: netdev@vger.kernel.org
---
Notes:
ver #5)
- Split iscsi changes into client and target patches
drivers/scsi/iscsi_tcp.c | 26 ++++++++++----------------
drivers/scsi/iscsi_tcp.h | 2 --
2 files changed, 10 insertions(+), 18 deletions(-)
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 9637d4bc2bc9..9ab8555180a3 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c@@ -301,35 +301,32 @@ static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn, while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) { struct scatterlist *sg; + struct msghdr msg = {}; + struct bio_vec bv; unsigned int offset, copy; - int flags = 0; r = 0; offset = segment->copied; copy = segment->size - offset; if (segment->total_copied + segment->size < segment->total_size) - flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST; + msg.msg_flags |= MSG_MORE; if (tcp_sw_conn->queue_recv) - flags |= MSG_DONTWAIT; + msg.msg_flags |= MSG_DONTWAIT; - /* Use sendpage if we can; else fall back to sendmsg */ if (!segment->data) { + if (!tcp_conn->iscsi_conn->datadgst_en) + msg.msg_flags |= MSG_SPLICE_PAGES; sg = segment->sg; offset += segment->sg_offset + sg->offset; - r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset, - copy, flags); + bvec_set_page(&bv, sg_page(sg), copy, offset); } else { - struct msghdr msg = { .msg_flags = flags }; - struct kvec iov = { - .iov_base = segment->data + offset, - .iov_len = copy - }; - - r = kernel_sendmsg(sk, &msg, &iov, 1, copy); + bvec_set_virt(&bv, segment->data + offset, copy); } + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bv, 1, copy); + r = sock_sendmsg(sk, &msg); if (r < 0) { iscsi_tcp_segment_unmap(segment); return r;
@@ -746,7 +743,6 @@ iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session, sock_no_linger(sk); iscsi_sw_tcp_conn_set_callbacks(conn); - tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage; /* * set receive state machine into initial state */
@@ -777,8 +773,6 @@ static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn, return -ENOTCONN; } iscsi_set_param(cls_conn, param, buf, buflen); - tcp_sw_conn->sendpage = conn->datadgst_en ? - sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage; mutex_unlock(&tcp_sw_conn->sock_lock); break; case ISCSI_PARAM_MAX_R2T:
diff --git a/drivers/scsi/iscsi_tcp.h b/drivers/scsi/iscsi_tcp.h
index 68e14a344904..89a6fc552f0b 100644
--- a/drivers/scsi/iscsi_tcp.h
+++ b/drivers/scsi/iscsi_tcp.h@@ -47,8 +47,6 @@ struct iscsi_sw_tcp_conn { /* MIB custom statistics */ uint32_t sendpage_failures_cnt; uint32_t discontiguous_hdr_cnt; - - ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int); }; struct iscsi_sw_tcp_host {