From mboxrd@z Thu Jan 1 00:00:00 1970 From: piaojun Message-ID: <5D4A7952.4010707@huawei.com> Date: Wed, 7 Aug 2019 15:10:10 +0800 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Subject: [Virtio-fs] [PATCH v2 2/2][RFC] use fuse_buf_writev to replace fuse_buf_write for better performance List-Id: Development discussions about virtio-fs List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: virtio-fs@redhat.com fuse_buf_writev() only handles the normal write in which src is buffer and dest is fd. Specially if src buffer represents guest physical address that can't be mapped by the daemon process, IO must be bounced back to the VMM to do it by fuse_buf_copy(). Signed-off-by: Jun Piao Suggested-by: Dr. David Alan Gilbert --- contrib/virtiofsd/passthrough_ll.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/contrib/virtiofsd/passthrough_ll.c b/contrib/virtiofsd/passthrough_ll.c index cc9c175..c1bbc53 100644 --- a/contrib/virtiofsd/passthrough_ll.c +++ b/contrib/virtiofsd/passthrough_ll.c @@ -2023,7 +2023,10 @@ static void lo_write_buf(fuse_req_t req, fuse_ino_t ino, fuse_debug("lo_write_buf(ino=%" PRIu64 ", size=%zd, off=%lu)\n", ino, out_buf.buf[0].size, (unsigned long) off); - res = fuse_buf_copy(req, &out_buf, in_buf, 0); + if (!(in_buf->buf[0].flags & FUSE_BUF_PHYS_ADDR)) + res = fuse_buf_writev(req, &out_buf, in_buf, out_buf.buf[0].flags); + else + res = fuse_buf_copy(req, &out_buf, in_buf, 0); if(res < 0) { fuse_reply_err(req, -res); } else { --