From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40428) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dQIDj-0004cz-DH for qemu-devel@nongnu.org; Wed, 28 Jun 2017 15:01:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dQIDi-0008Al-3n for qemu-devel@nongnu.org; Wed, 28 Jun 2017 15:01:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43112) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dQIDh-0008AF-Tq for qemu-devel@nongnu.org; Wed, 28 Jun 2017 15:01:46 -0400 From: "Dr. David Alan Gilbert (git)" Date: Wed, 28 Jun 2017 20:00:28 +0100 Message-Id: <20170628190047.26159-11-dgilbert@redhat.com> In-Reply-To: <20170628190047.26159-1-dgilbert@redhat.com> References: <20170628190047.26159-1-dgilbert@redhat.com> Subject: [Qemu-devel] [RFC 10/29] vhub: Open userfaultfd List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, a.perevalov@samsung.com, marcandre.lureau@redhat.com, maxime.coquelin@redhat.com, mst@redhat.com, quintela@redhat.com, peterx@redhat.com, lvivier@redhat.com, aarcange@redhat.com From: "Dr. David Alan Gilbert" Open a userfaultfd (on a postcopy_advise) and send it back in the reply to the qemu for it to monitor. Signed-off-by: Dr. David Alan Gilbert --- contrib/libvhost-user/libvhost-user.c | 24 +++++++++++++++++++++--- contrib/libvhost-user/libvhost-user.h | 3 +++ 2 files changed, 24 insertions(+), 3 deletions(-) diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index e3a32755cf..62e97f6b84 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -15,6 +15,7 @@ #include #include +#include #include #include "qemu/atomic.h" @@ -774,11 +775,28 @@ vu_set_vring_enable_exec(VuDev *dev, VhostUserMsg *vmsg) static bool vu_set_postcopy_advise(VuDev *dev, VhostUserMsg *vmsg) { - /* TODO: Open ufd, pass it back in the request - /* TODO: Add addresses - */ + struct uffdio_api api_struct; + + dev->postcopy_ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + /* TODO: Add addresses */ vmsg->payload.u64 = 0xcafe; vmsg->size = sizeof(vmsg->payload.u64); + + if (dev->postcopy_ufd == -1) { + vu_panic(dev, "Userfaultfd not available: %s", strerror(errno)); + return false; + } + api_struct.api = UFFD_API; + api_struct.features = 0; + if (ioctl(dev->postcopy_ufd, UFFDIO_API, &api_struct)) { + vu_panic(dev, "Failed UFFDIO_API: %s", strerror(errno)); + close(dev->postcopy_ufd); + return false; + } + /* TODO: Stash feature flags somewhere */ + /* Return a ufd to the QEMU */ + vmsg->fd_num = 1; + vmsg->fds[0] = dev->postcopy_ufd; return true; /* = send a reply */ } diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h index 8bb35582ea..3e65a962da 100644 --- a/contrib/libvhost-user/libvhost-user.h +++ b/contrib/libvhost-user/libvhost-user.h @@ -231,6 +231,9 @@ struct VuDev { * re-initialize */ vu_panic_cb panic; const VuDevIface *iface; + + /* Postcopy data */ + int postcopy_ufd; }; typedef struct VuVirtqElement { -- 2.13.0