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Re: [Qemu-devel] [PATCH 2/4] Qemu-Xen-vTPM: Register Xen stubdom vTPM fr
From: |
Stefano Stabellini |
Subject: |
Re: [Qemu-devel] [PATCH 2/4] Qemu-Xen-vTPM: Register Xen stubdom vTPM frontend driver |
Date: |
Wed, 5 Nov 2014 11:01:26 +0000 |
User-agent: |
Alpine 2.02 (DEB 1266 2009-07-14) |
On Tue, 4 Nov 2014, Xu, Quan wrote:
> > -----Original Message-----
> > From: Stefano Stabellini [mailto:address@hidden
> > Sent: Monday, November 03, 2014 7:54 PM
> > To: Xu, Quan
> > Cc: address@hidden; address@hidden;
> > address@hidden
> > Subject: Re: [PATCH 2/4] Qemu-Xen-vTPM: Register Xen stubdom vTPM
> > frontend driver
> >
> > On Sun, 2 Nov 2014, Quan Xu wrote:
> > > This drvier transfers any request/repond between TPM xenstubdoms
> > > driver and Xen vTPM stubdom, and facilitates communications between
> > > Xen vTPM stubdom domain and vTPM xenstubdoms driver
> > >
> > > Signed-off-by: Quan Xu <address@hidden>
> >
> > Please describe what changes did make to xen_backend.c and why.
> > The commit message should contains info on all the changes made by the
> > patch below.
> >
>
> Thanks Stefano.
> one more day, I will explain in detail what changes did make to xen_backend.c
> and why.
> The following 2 sections are introduction and architecture.
>
> > Please also describe what is the "Xen vTPM stubdom", what is the
> > "vTPM xenstubdoms driver" and how the communicate with each others.
> >
>
>
> Add 2 parts for detailed descriptions, introduction and architecture.
>
> *INTRODUCTION*
>
> The goal of virtual Trusted Platform Module (vTPM) is to provide a TPM
> functionality
> to virtual machines (Fedora, Ubuntu, Redhat, Windows .etc). This allows
> programs to
> interact with a TPM in a virtual machine the same way they interact with a
> TPM on the
> physical system. Each virtual machine gets its own unique, emulated, software
> TPM.
> Each major component of vTPM is implemented as a stubdom, providing secure
> separation
> guaranteed by the hypervisor.
> The vTPM stubdom is a Xen mini-OS domain that emulates a TPM for the virtual
> machine
> to use. It is a small wrapper around the Berlios TPM emulator. TPM commands
> are passed
> from mini-os TPM backend driver.
> This patch series are only the Qemu part to enable Xen stubdom vTPM for HVM
> virtual
> machine.
> ===========
>
> *ARCHITECTURE*
>
> The architecture of stubdom vTPM for HVM virtual machine:
>
> +--------------------+
> | Windows/Linux DomU | ...
> | | ^ |
> | v | |
> | Qemu tpm1.2 Tis |
> | | ^ |
> | v | |
> | vTPM |
> | XenStubdoms driver | (new ..)
> +--------------------+
> | ^
> v |
> +--------------------+
> | xen_vtpmdev_ops | (new ..)
> +--------------------+
> | ^
> v |
> +--------------------+
> | mini-os/tpmback |
> | | ^ |
> | v | |
> | vTPM stubdom | ...
> | | ^ |
> | v | |
> | mini-os/tpmfront |
> +--------------------+
> | ^
> v |
> +--------------------+
> | mini-os/tpmback |
> | | ^ |
> | v | |
> | vtpmmgr stubdom |
> | | ^ |
> | v | |
> | mini-os/tpm_tis |
> +--------------------+
> | ^
> v |
> +--------------------+
> | Hardware TPM |
> +--------------------+
>
>
> * Windows/Linux DomU:
> The HVM based guest that wants to use a vTPM. There may be
> more than one of these.
>
> * Qemu tpm1.2 Tis:
> Implementation of the tpm1.2 Tis interface for HVM virtual
> machines. It is Qemu emulation device.
It looks like you are running upstream QEMU within a Mini-OS stubdom?
If so, where are the patches to do that? As far as I know upstream QEMU
doesn't run on Mini-OS. Or maybe it is a Linux stubdom? Either way, it
is not clear.
> * vTPM xenstubdoms driver:
> Similar to a TPM passthrough backend driver, it is a new TPM
> backend for emulated TPM TIS interface. This driver provides
> vTPM initialization and sending data and commends to a Xen
> vTPM stubdom.
This is patch #3, right? It is basically the internal QEMU "glue" to
connect the tpm emulator to xen_vtpmdev_ops, correct?
> * xen_vtpmdev_ops:
> Register Xen stubdom vTPM backend, and transfer any request/
> repond between TPM xenstubdoms driver and Xen vTPM stubdom.
> Facilitate communications between Xen vTPM stubdom and vTPM
> xenstubdoms driver.
It looks like this correspond to patch #2? If so, this is a regular Xen
PV frontend, living in QEMU? It requires the gntalloc device so I guess
it is supposed to run on Linux. In that case is it just a tpmfront
implementation in QEMU?
If you are running it on Linux, we might need to introduce Linux based
stundoms to the Xen build system.
> * mini-os/tpmback:
> Mini-os TPM backend driver. The Linux frontend driver connects
> to this backend driver to facilitate communications between the
> Linux DomU and its vTPM. This driver is also used by vtpmmgr
> stubdom to communicate with vTPM stubdom.
>
> * vTPM stubdom:
> A mini-os stub domain that implements a vTPM. There is a
> one to one mapping between running vTPM stubdom instances and
> logical vTPMs on the system. The vTPM Platform Configuration
> Registers (PCRs) are all initialized to zero.
>
> * mini-os/tpmfront:
> Mini-os TPM frontend driver. The vTPM mini-os domain vTPM
> stubdom uses this driver to communicate with vtpmmgr-stubdom.
> This driver could also be used separately to implement a mini-os
> domain that wishes to use a vTPM of its own.
>
> * vtpmmgr stubdom:
> A mini-os domain that implements the vTPM manager. There is only
> one vTPM manager and it should be running during the entire lifetime
> of the machine. vtpmmgr domain securely stores encryption keys for
> each of the vTPMs and accesses to the hardware TPM to get the root of
> trust for the entire system.
>
> * mini-os/tpm_tis:
> Mini-os TPM version 1.2 TPM Interface Specification (TIS) driver.
> This driver used by vtpmmgr-stubdom to talk directly to the hardware
> TPM. Communication is facilitated by mapping hardware memory pages
> into vtpmmgr stubdom.
Are all the Mini-OS component upstream, or do we need patches?
> * Hardware TPM:
> The physical TPM 1.2 that is soldered onto the motherboard.
>
> ===========
>
>
>
> > Where does the vTPM backend lives?
> The vTPM backend lives in Xen vTPM stubdom (Xen Mini-os)
Thanks for the explanation, it is a bit clearer now.
> >
> >
> > > hw/xen/Makefile.objs | 1 +
> > > hw/xen/xen_backend.c | 182 ++++++++++++++++++++++-
> > > hw/xen/xen_stubdom_vtpm.c | 333
> > +++++++++++++++++++++++++++++++++++++++++++
> > > include/hw/xen/xen_backend.h | 11 ++
> > > include/hw/xen/xen_common.h | 6 +
> > > xen-hvm.c | 13 ++
> > > 6 files changed, 544 insertions(+), 2 deletions(-)
> > > create mode 100644 hw/xen/xen_stubdom_vtpm.c
> > >
> > > diff --git a/hw/xen/Makefile.objs b/hw/xen/Makefile.objs
> > > index a0ca0aa..724df8d 100644
> > > --- a/hw/xen/Makefile.objs
> > > +++ b/hw/xen/Makefile.objs
> > > @@ -1,5 +1,6 @@
> > > # xen backend driver support
> > > common-obj-$(CONFIG_XEN_BACKEND) += xen_backend.o
> > xen_devconfig.o
> > > +common-obj-$(CONFIG_TPM_XENSTUBDOMS) += xen_stubdom_vtpm.o
> > >
> > > obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen-host-pci-device.o
> > > obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen_pt.o
> > xen_pt_config_init.o xen_pt_msi.o
> > > diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c
> > > index b2cb22b..45a5778 100644
> > > --- a/hw/xen/xen_backend.c
> > > +++ b/hw/xen/xen_backend.c
> > > @@ -194,6 +194,32 @@ int xen_be_set_state(struct XenDevice *xendev,
> > enum xenbus_state state)
> > > return 0;
> > > }
> > >
> > > +/*get stubdom backend*/
> > > +static char *xen_stubdom_be(const char *type, int dom, int dev)
> > > +{
> > > + char *val, *domu;
> > > + char path[XEN_BUFSIZE];
> > > + unsigned int len, ival;
> > > +
> > > + /*front domu*/
> > > + domu = xs_get_domain_path(xenstore, dom);
> > > + snprintf(path, sizeof(path), "%s/device/%s/%d/backend-id",
> > > + domu, type, dev);
> > > + g_free(domu);
> > > +
> > > + val = xs_read(xenstore, 0, path, &len);
> > > + if (!val || 1 != sscanf(val, "%d", &ival)) {
> > > + g_free(val);
> > > + return NULL;
> > > + }
> > > + g_free(val);
> > > +
> > > + /*backend domu*/
> > > + domu = xs_get_domain_path(xenstore, ival);
> > > +
> > > + return domu;
> > > +}
> > > +
> > > /* ------------------------------------------------------------- */
> > >
> > > struct XenDevice *xen_be_find_xendev(const char *type, int dom, int
> > dev)
> > > @@ -222,6 +248,7 @@ static struct XenDevice *xen_be_get_xendev(const
> > char *type, int dom, int dev,
> > > struct XenDevOps *ops)
> > > {
> > > struct XenDevice *xendev;
> > > + char *stub;
> > >
> > > xendev = xen_be_find_xendev(type, dom, dev);
> > > if (xendev) {
> > > @@ -235,8 +262,15 @@ static struct XenDevice
> > *xen_be_get_xendev(const char *type, int dom, int dev,
> > > xendev->dev = dev;
> > > xendev->ops = ops;
> > >
> > > - snprintf(xendev->be, sizeof(xendev->be), "backend/%s/%d/%d",
> > > - xendev->type, xendev->dom, xendev->dev);
> > > + if (ops->flags & DEVOPS_FLAG_STUBDOM_BE) {
> > > + stub = xen_stubdom_be(xendev->type, xendev->dom,
> > xendev->dev);
> > > + snprintf(xendev->be, sizeof(xendev->be),
> > "%s/backend/%s/%d/%d",
> > > + stub, xendev->type, xendev->dom, xendev->dev);
> > > + g_free(stub);
> > > + } else {
> > > + snprintf(xendev->be, sizeof(xendev->be), "backend/%s/%d/%d",
> > > + xendev->type, xendev->dom, xendev->dev);
> > > + }
> > > snprintf(xendev->name, sizeof(xendev->name), "%s-%d",
> > > xendev->type, xendev->dev);
> > >
> > > @@ -611,6 +645,47 @@ static int xenstore_scan(const char *type, int
> > dom, struct XenDevOps *ops)
> > > return 0;
> > > }
> > >
> > > +static void stubdom_update_be(char *watch, char *type, int dom,
> > > + struct XenDevOps *ops)
> > > +{
> > > + struct XenDevice *xendev;
> > > + char path[XEN_BUFSIZE];
> > > + char *ptr, *bepath;
> > > + unsigned int len, dev;
> > > +
> > > + if (!(ops->flags & DEVOPS_FLAG_STUBDOM_BE)) {
> > > + return;
> > > + }
> > > +
> > > + len = snprintf(path, sizeof(path), "backend/%s/%d", type, dom);
> > > + ptr = strstr(watch, path);
> > > + if (ptr == NULL) {
> > > + return;
> > > + }
> > > +
> > > + if (sscanf(ptr+len, "/%u/%255s", &dev, path) != 2) {
> > > + strcpy(path, "");
> > > + if (sscanf(ptr+len, "/%u", &dev) != 1) {
> > > + dev = -1;
> > > + }
> > > + }
> > > +
> > > + if (dev == -1) {
> > > + return;
> > > + }
> > > +
> > > + xendev = xen_be_get_xendev(type, dom, dev, ops);
> > > + if (xendev != NULL) {
> > > + bepath = xs_read(xenstore, 0, xendev->be, &len);
> > > + if (bepath == NULL) {
> > > + xen_be_del_xendev(dom, dev);
> > > + } else {
> > > + free(bepath);
> > > + xen_be_backend_changed(xendev, path);
> > > + }
> > > + }
> > > +}
> > > +
> > > static void xenstore_update_be(char *watch, char *type, int dom,
> > > struct XenDevOps *ops)
> > > {
> > > @@ -681,6 +756,10 @@ static void xenstore_update(void *unused)
> > > if (sscanf(vec[XS_WATCH_TOKEN], "fe:%" PRIxPTR, &ptr) == 1) {
> > > xenstore_update_fe(vec[XS_WATCH_PATH], (void*)ptr);
> > > }
> > > + if (sscanf(vec[XS_WATCH_TOKEN], "stub:%" PRIxPTR ":%d:%"
> > PRIxPTR,
> > > + &type, &dom, &ops) == 3) {
> > > + stubdom_update_be(vec[XS_WATCH_PATH], (void *)type, dom,
> > (void *)ops);
> > > + }
> > >
> > > cleanup:
> > > free(vec);
> > > @@ -732,11 +811,74 @@ err:
> > > return -1;
> > > }
> > >
> > > +int xen_vtpm_register(struct XenDevOps *ops)
> > > +{
> > > + struct XenDevice *xendev;
> > > + char path[XEN_BUFSIZE], token[XEN_BUFSIZE];
> > > + char *domu;
> > > + unsigned int cdev, j, rc;
> > > + const char *type = "vtpm";
> > > + char **dev = NULL;
> > > +
> > > + /*front domu*/
> > > + domu = xs_get_domain_path(xenstore, xen_domid);
> > > + snprintf(path, sizeof(path), "%s/device/%s",
> > > + domu, type);
> > > + free(domu);
> > > + dev = xs_directory(xenstore, 0, path, &cdev);
> > > + if (dev == NULL) {
> > > + return 0;
> > > + }
> > > +
> > > + for (j = 0; j < cdev; j++) {
> > > + xendev = xen_be_get_xendev(type, xen_domid, atoi(dev[j]),
> > ops);
> > > + if (xendev == NULL) {
> > > + xen_be_printf(xendev, 0, "xen_vtpm_register xendev is
> > NULL.\n");
> > > + continue;
> > > + }
> > > +
> > > + if (xendev->ops->initialise) {
> > > + rc = xendev->ops->initialise(xendev);
> > > +
> > > + /*if initialise failed, delete it*/
> > > + if (rc != 0) {
> > > + xen_be_del_xendev(xen_domid, atoi(dev[j]));
> > > + continue;
> > > + }
> > > + }
> > > +
> > > + /*setup watch*/
> > > + snprintf(token, sizeof(token), "stub:%p:%d:%p",
> > > + type, xen_domid, xendev->ops);
> > > + if (!xs_watch(xenstore, xendev->be, token)) {
> > > + xen_be_printf(xendev, 0, "xen_vtpm_register xs_watch
> > failed.\n");
> > > + return -1;
> > > + }
> > > + }
> > > +
> > > + free(dev);
> > > + return 0;
> > > +}
> >
> > What does this function do? I sholdn't need to guess from the code, I
> > should be able to tell from the patch description.
> >
> >
> > > int xen_be_register(const char *type, struct XenDevOps *ops)
> > > {
> > > return xenstore_scan(type, xen_domid, ops);
> > > }
> > >
> > > +int xen_be_alloc_unbound(struct XenDevice *xendev, int dom, int
> > remote_dom)
> > > +{
> > > + xendev->local_port =
> > xc_evtchn_bind_unbound_port(xendev->evtchndev,
> > > +
> > remote_dom);
> > > + if (xendev->local_port == -1) {
> > > + xen_be_printf(xendev, 0, "xc_evtchn_alloc_unbound failed\n");
> > > + return -1;
> > > + }
> > > + xen_be_printf(xendev, 2, "bind evtchn port %d\n",
> > xendev->local_port);
> > > + qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev),
> > > + xen_be_evtchn_event, NULL, xendev);
> > > + return 0;
> > > +}
> > > +
> > > int xen_be_bind_evtchn(struct XenDevice *xendev)
> > > {
> > > if (xendev->local_port != -1) {
> > > @@ -770,6 +912,42 @@ int xen_be_send_notify(struct XenDevice
> > *xendev)
> > > return xc_evtchn_notify(xendev->evtchndev, xendev->local_port);
> > > }
> > >
> > > +int xen_vtpm_send(unsigned char *buf, size_t count)
> > > +{
> > > + struct XenDevice *xendev;
> > > + int rc = -1;
> > > +
> > > + xendev = xen_be_find_xendev("vtpm", xen_domid, 0);
> > > + if (xendev == NULL) {
> > > + xen_be_printf(xendev, 0, "Con not find vtpm device\n");
> > > + return -1;
> > > + }
> > > +
> > > + if (xendev->ops->send) {
> > > + rc = xendev->ops->send(xendev, buf, count);
> > > + }
> > > +
> > > + return rc;
> > > +}
> > > +
> > > +int xen_vtpm_recv(unsigned char *buf, size_t *count)
> > > +{
> > > + struct XenDevice *xendev;
> > > + int rc = -1;
> > > +
> > > + xendev = xen_be_find_xendev("vtpm", xen_domid, 0);
> > > + if (xendev == NULL) {
> > > + xen_be_printf(xendev, 0, "Con not find vtpm device\n");
> > > + return -1;
> > > + }
> > > +
> > > + if (xendev->ops->recv) {
> > > + xendev->ops->recv(xendev, buf, count);
> > > + }
> > > +
> > > + return rc;
> > > +}
> >
> > xen_backend.c is supposed to be generic, so stubdom functions might be
> > OK but vtpm specific functions should not be here.
> >
> >
> > > /*
> > > * msg_level:
> > > * 0 == errors (stderr + logfile).
> > > diff --git a/hw/xen/xen_stubdom_vtpm.c b/hw/xen/xen_stubdom_vtpm.c
> > > new file mode 100644
> > > index 0000000..0d740c1
> > > --- /dev/null
> > > +++ b/hw/xen/xen_stubdom_vtpm.c
> > > @@ -0,0 +1,333 @@
> > > +/*
> > > + * Connect to Xen vTPM stubdom domain
> > > + *
> > > + * Copyright (c) 2014 Intel Corporation
> > > + * Authors:
> > > + * Quan Xu <address@hidden>
> > > + *
> > > + * This library is free software; you can redistribute it and/or
> > > + * modify it under the terms of the GNU Lesser General Public
> > > + * License as published by the Free Software Foundation; either
> > > + * version 2 of the License, or (at your option) any later version.
> > > + *
> > > + * This library is distributed in the hope that it will be useful,
> > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > GNU
> > > + * Lesser General Public License for more details.
> > > + *
> > > + * You should have received a copy of the GNU Lesser General Public
> > > + * License along with this library; if not, see
> > <http://www.gnu.org/licenses/>
> > > + */
> > > +
> > > +#include <stdio.h>
> > > +#include <stdlib.h>
> > > +#include <stdarg.h>
> > > +#include <string.h>
> > > +#include <unistd.h>
> > > +#include <signal.h>
> > > +#include <inttypes.h>
> > > +#include <time.h>
> > > +#include <fcntl.h>
> > > +#include <errno.h>
> > > +#include <sys/ioctl.h>
> > > +#include <sys/types.h>
> > > +#include <sys/stat.h>
> > > +#include <sys/mman.h>
> > > +#include <sys/uio.h>
> > > +
> > > +#include "hw/hw.h"
> > > +#include "block/aio.h"
> > > +#include "hw/xen/xen_backend.h"
> > > +
> > > +enum tpmif_state {
> > > + TPMIF_STATE_IDLE, /* no contents / vTPM idle / cancel
> > complete */
> > > + TPMIF_STATE_SUBMIT, /* request ready / vTPM working */
> > > + TPMIF_STATE_FINISH, /* response ready / vTPM idle */
> > > + TPMIF_STATE_CANCEL, /* cancel requested / vTPM working */
> > > +};
> > > +
> > > +static AioContext *vtpm_aio_ctx;
> > > +
> > > +enum status_bits {
> > > + VTPM_STATUS_RUNNING = 0x1,
> > > + VTPM_STATUS_IDLE = 0x2,
> > > + VTPM_STATUS_RESULT = 0x4,
> > > + VTPM_STATUS_CANCELED = 0x8,
> > > +};
> > > +
> > > +struct tpmif_shared_page {
> > > + uint32_t length; /* request/response length in bytes */
> > > +
> > > + uint8_t state; /* enum tpmif_state */
> > > + uint8_t locality; /* for the current request */
> > > + uint8_t pad; /* should be zero */
> > > +
> > > + uint8_t nr_extra_pages; /* extra pages for long packets; may be
> > zero */
> > > + uint32_t extra_pages[0]; /* grant IDs; length is actually
> > nr_extra_pages */
> > > +};
> > > +
> > > +struct QEMUBH {
> > > + AioContext *ctx;
> > > + QEMUBHFunc *cb;
> > > + void *opaque;
> > > + QEMUBH *next;
> > > + bool scheduled;
> > > + bool idle;
> > > + bool deleted;
> > > +};
> > > +
> > > +struct XenVtpmDev {
> > > + struct XenDevice xendev; /* must be first */
> > > + struct tpmif_shared_page *shr;
> > > + xc_gntshr *xen_xcs;
> > > + int ring_ref;
> > > + int bedomid;
> > > + QEMUBH *sr_bh;
> > > +};
> > > +
> > > +static uint8_t vtpm_status(struct XenVtpmDev *vtpmdev)
> > > +{
> > > + switch (vtpmdev->shr->state) {
> > > + case TPMIF_STATE_IDLE:
> > > + case TPMIF_STATE_FINISH:
> > > + return VTPM_STATUS_IDLE;
> > > + case TPMIF_STATE_SUBMIT:
> > > + case TPMIF_STATE_CANCEL:
> > > + return VTPM_STATUS_RUNNING;
> > > + default:
> > > + return 0;
> > > + }
> > > +}
> > > +
> > > +static int xenbus_switch_state(struct XenDevice *xendev, enum
> > xenbus_state xbus)
> > > +{
> > > + xs_transaction_t xbt = XBT_NULL;
> > > +
> > > + if (xendev->fe_state == xbus) {
> > > + return 0;
> > > + }
> > > +
> > > + xendev->fe_state = xbus;
> > > +
> > > +retry_transaction:
> > > + xbt = xs_transaction_start(xenstore);
> > > + if (xbt == XBT_NULL) {
> > > + goto abort_transaction;
> > > + }
> > > +
> > > + if (xenstore_write_int(xendev->fe, "state", xbus)) {
> > > + goto abort_transaction;
> > > + }
> > > +
> > > + if (!xs_transaction_end(xenstore, xbt, 0)) {
> > > + if (errno == EAGAIN) {
> > > + goto retry_transaction;
> > > + }
> > > + }
> > > +
> > > + return 0;
> > > +
> > > +abort_transaction:
> > > + xs_transaction_end(xenstore, xbt, 1);
> > > + return -1;
> > > +}
> > > +
> > > +static int vtpm_aio_wait(QEMUBH *qbh)
> > > +{
> > > + return aio_poll(qbh->ctx, true);
> > > +}
> > > +
> > > +static void sr_bh_handler(void *opaque)
> > > +{
> > > +}
> > > +
> > > +static int vtpm_recv(struct XenDevice *xendev, uint8_t* buf, size_t
> > *count)
> > > +{
> > > + struct XenVtpmDev *vtpmdev = container_of(xendev, struct
> > XenVtpmDev,
> > > + xendev);
> > > + struct tpmif_shared_page *shr = vtpmdev->shr;
> > > + unsigned int offset;
> > > +
> > > + if (shr->state == TPMIF_STATE_IDLE) {
> > > + return -ECANCELED;
> > > + }
> > > +
> > > + while (vtpm_status(vtpmdev) != VTPM_STATUS_IDLE) {
> > > + vtpm_aio_wait(vtpmdev->sr_bh);
> > > + }
> > > +
> > > + offset = sizeof(*shr) + 4*shr->nr_extra_pages;
> > > + memcpy(buf, offset + (uint8_t *)shr, shr->length);
> > > + *count = shr->length;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int vtpm_send(struct XenDevice *xendev, uint8_t* buf, size_t
> > count)
> > > +{
> > > + struct XenVtpmDev *vtpmdev = container_of(xendev, struct
> > XenVtpmDev,
> > > + xendev);
> > > + struct tpmif_shared_page *shr = vtpmdev->shr;
> > > + unsigned int offset = sizeof(*shr) + 4*shr->nr_extra_pages;
> > > +
> > > + while (vtpm_status(vtpmdev) != VTPM_STATUS_IDLE) {
> > > + vtpm_aio_wait(vtpmdev->sr_bh);
> > > + }
> > > +
> > > + memcpy(offset + (uint8_t *)shr, buf, count);
> > > + shr->length = count;
> > > + barrier();
> > > + shr->state = TPMIF_STATE_SUBMIT;
> > > + xen_wmb();
> > > + xen_be_send_notify(&vtpmdev->xendev);
> > > +
> > > + while (vtpm_status(vtpmdev) != VTPM_STATUS_IDLE) {
> > > + vtpm_aio_wait(vtpmdev->sr_bh);
> > > + }
> > > +
> > > + return count;
> > > +}
> > > +
> > > +static int vtpm_initialise(struct XenDevice *xendev)
> > > +{
> > > + struct XenVtpmDev *vtpmdev = container_of(xendev, struct
> > XenVtpmDev,
> > > + xendev);
> > > + xs_transaction_t xbt = XBT_NULL;
> > > + unsigned int ring_ref;
> > > +
> > > + vtpmdev->xendev.fe = xenstore_read_be_str(&vtpmdev->xendev,
> > "frontend");
> > > + if (vtpmdev->xendev.fe == NULL) {
> > > + return -1;
> > > + }
> > > +
> > > + /* Get backend domid */
> > > + if (xenstore_read_fe_int(&vtpmdev->xendev, "backend-id",
> > > + &vtpmdev->bedomid)) {
> > > + return -1;
> > > + }
> > > +
> > > + /*alloc share page*/
> > > + vtpmdev->shr = xc_gntshr_share_pages(vtpmdev->xen_xcs,
> > vtpmdev->bedomid, 1,
> > > + &ring_ref,
> > PROT_READ|PROT_WRITE);
> > > + vtpmdev->ring_ref = ring_ref;
> > > + if (vtpmdev->shr == NULL) {
> > > + return -1;
> > > + }
> > > +
> > > + /*Create event channel */
> > > + if (xen_be_alloc_unbound(&vtpmdev->xendev, 0,
> > vtpmdev->bedomid)) {
> > > + xc_gntshr_munmap(vtpmdev->xen_xcs, vtpmdev->shr, 1);
> > > + return -1;
> > > + }
> > > +
> > > + xc_evtchn_unmask(vtpmdev->xendev.evtchndev,
> > > + vtpmdev->xendev.local_port);
> > > +
> > > +again:
> > > + xbt = xs_transaction_start(xenstore);
> > > + if (xbt == XBT_NULL) {
> > > + goto abort_transaction;
> > > + }
> > > +
> > > + if (xenstore_write_int(vtpmdev->xendev.fe, "ring-ref",
> > > + vtpmdev->ring_ref)) {
> > > + goto abort_transaction;
> > > + }
> > > +
> > > + if (xenstore_write_int(vtpmdev->xendev.fe, "event-channel",
> > > + vtpmdev->xendev.local_port)) {
> > > + goto abort_transaction;
> > > + }
> > > +
> > > + /* Publish protocol v2 feature */
> > > + if (xenstore_write_int(vtpmdev->xendev.fe, "feature-protocol-v2", 1))
> > {
> > > + goto abort_transaction;
> > > + }
> > > +
> > > + if (!xs_transaction_end(xenstore, xbt, 0)) {
> > > + if (errno == EAGAIN) {
> > > + goto again;
> > > + }
> > > + }
> > > + /* Tell vtpm backend that we are ready */
> > > + xenbus_switch_state(&vtpmdev->xendev, XenbusStateInitialised);
> > > +
> > > + return 0;
> > > +
> > > +abort_transaction:
> > > + xc_gntshr_munmap(vtpmdev->xen_xcs, vtpmdev->shr, 1);
> > > + xs_transaction_end(xenstore, xbt, 1);
> > > + return -1;
> > > +}
> > > +
> > > +static void vtpm_backend_changed(struct XenDevice *xendev, const char
> > *node)
> > > +{
> > > + struct XenVtpmDev *vtpmdev = container_of(xendev, struct
> > XenVtpmDev,
> > > + xendev);
> > > + int be_state;
> > > +
> > > + if (strcmp(node, "state") == 0) {
> > > + xenstore_read_be_int(&vtpmdev->xendev, node, &be_state);
> > > + switch (be_state) {
> > > + case XenbusStateConnected:
> > > + /*TODO*/
> > > + break;
> > > + case XenbusStateClosing:
> > > + case XenbusStateClosed:
> > > + xenbus_switch_state(&vtpmdev->xendev,
> > XenbusStateClosing);
> > > + break;
> > > + default:
> > > + break;
> > > + }
> > > + }
> > > +}
> > > +
> > > +static int vtpm_free(struct XenDevice *xendev)
> > > +{
> > > + struct XenVtpmDev *vtpmdev = container_of(xendev, struct
> > XenVtpmDev,
> > > + xendev);
> > > + QEMUBH *qbh = vtpmdev->sr_bh;
> > > +
> > > + aio_poll(qbh->ctx, false);
> > > + qemu_bh_delete(vtpmdev->sr_bh);
> > > + if (vtpmdev->shr) {
> > > + xc_gntshr_munmap(vtpmdev->xen_xcs, vtpmdev->shr, 1);
> > > + }
> > > + xc_interface_close(vtpmdev->xen_xcs);
> > > + return 0;
> > > +}
> > > +
> > > +static void vtpm_alloc(struct XenDevice *xendev)
> > > +{
> > > + struct XenVtpmDev *vtpmdev = container_of(xendev, struct
> > XenVtpmDev,
> > > + xendev);
> > > +
> > > + vtpm_aio_ctx = aio_context_new(NULL);
> > > + if (vtpm_aio_ctx == NULL) {
> > > + return;
> > > + }
> > > + vtpmdev->sr_bh = aio_bh_new(vtpm_aio_ctx, sr_bh_handler,
> > vtpmdev);
> > > + qemu_bh_schedule(vtpmdev->sr_bh);
> > > + vtpmdev->xen_xcs = xen_xc_gntshr_open(0, 0);
> > > +}
> > > +
> > > +static void vtpm_event(struct XenDevice *xendev)
> > > +{
> > > + struct XenVtpmDev *vtpmdev = container_of(xendev, struct
> > XenVtpmDev,
> > > + xendev);
> > > +
> > > + qemu_bh_schedule(vtpmdev->sr_bh);
> > > +}
> > > +
> > > +struct XenDevOps xen_vtpmdev_ops = {
> > > + .size = sizeof(struct XenVtpmDev),
> > > + .flags = DEVOPS_FLAG_IGNORE_STATE |
> > > + DEVOPS_FLAG_STUBDOM_BE,
> > > + .event = vtpm_event,
> > > + .free = vtpm_free,
> > > + .alloc = vtpm_alloc,
> > > + .initialise = vtpm_initialise,
> > > + .backend_changed = vtpm_backend_changed,
> > > + .recv = vtpm_recv,
> > > + .send = vtpm_send,
> > > +};
> >
> > Is this the frontend, like the subject line would seem to imply?
> > If so, XenDevOps are made for backends, while this is a frontend. In
> > fact this is the first PV frontend in QEMU. We need to introduce
> > something generic and similar to struct XenDevOps and xen_backend.c but
> > for frontends.
> >
> >
> > > diff --git a/include/hw/xen/xen_backend.h
> > b/include/hw/xen/xen_backend.h
> > > index 3b4125e..45fd6d3 100644
> > > --- a/include/hw/xen/xen_backend.h
> > > +++ b/include/hw/xen/xen_backend.h
> > > @@ -15,6 +15,8 @@ struct XenDevice;
> > > #define DEVOPS_FLAG_NEED_GNTDEV 1
> > > /* don't expect frontend doing correct state transitions (aka console
> > quirk) */
> > > #define DEVOPS_FLAG_IGNORE_STATE 2
> > > +/*dev backend is stubdom*/
> > > +#define DEVOPS_FLAG_STUBDOM_BE 4
> > >
> > > struct XenDevOps {
> > > size_t size;
> > > @@ -26,6 +28,8 @@ struct XenDevOps {
> > > void (*event)(struct XenDevice *xendev);
> > > void (*disconnect)(struct XenDevice *xendev);
> > > int (*free)(struct XenDevice *xendev);
> > > + int (*send)(struct XenDevice *xendev, uint8_t* buf, size_t
> > count);
> > > + int (*recv)(struct XenDevice *xendev, uint8_t* buf, size_t
> > *count);
> > > void (*backend_changed)(struct XenDevice *xendev, const
> > char *node);
> > > void (*frontend_changed)(struct XenDevice *xendev, const
> > char *node);
> > > };
> > > @@ -91,12 +95,19 @@ int xen_be_send_notify(struct XenDevice
> > *xendev);
> > > void xen_be_printf(struct XenDevice *xendev, int msg_level, const char
> > *fmt, ...)
> > > GCC_FMT_ATTR(3, 4);
> > >
> > > +/*Xen stubdom vtpm*/
> > > +int xen_vtpm_register(struct XenDevOps *ops);
> > > +int xen_be_alloc_unbound(struct XenDevice *xendev, int dom, int
> > remote_dom);
> > > +int xen_vtpm_send(unsigned char *buf, size_t count);
> > > +int xen_vtpm_recv(unsigned char *buf, size_t *count);
> > > +
> > > /* actual backend drivers */
> > > extern struct XenDevOps xen_console_ops; /* xen_console.c
> > */
> > > extern struct XenDevOps xen_kbdmouse_ops; /* xen_framebuffer.c
> > */
> > > extern struct XenDevOps xen_framebuffer_ops; /* xen_framebuffer.c */
> > > extern struct XenDevOps xen_blkdev_ops; /* xen_disk.c
> > */
> > > extern struct XenDevOps xen_netdev_ops; /* xen_nic.c
> > */
> > > +extern struct XenDevOps xen_vtpmdev_ops; /*
> > xen_stubdom_vtpm.c*/
> > >
> > > void xen_init_display(int domid);
> > >
> > > diff --git a/include/hw/xen/xen_common.h
> > b/include/hw/xen/xen_common.h
> > > index 95612a4..fb43084 100644
> > > --- a/include/hw/xen/xen_common.h
> > > +++ b/include/hw/xen/xen_common.h
> > > @@ -130,6 +130,12 @@ static inline XenXC xen_xc_interface_open(void
> > *logger, void *dombuild_logger,
> > > return xc_interface_open(logger, dombuild_logger, open_flags);
> > > }
> > >
> > > +static inline xc_gntshr *xen_xc_gntshr_open(void *logger,
> > > + unsigned int open_flags)
> > > +{
> > > + return xc_gntshr_open(logger, open_flags);
> > > +}
> > > +
> > > /* FIXME There is now way to have the xen fd */
> > > static inline int xc_fd(xc_interface *xen_xc)
> > > {
> > > diff --git a/xen-hvm.c b/xen-hvm.c
> > > index 21f1cbb..c99ace8 100644
> > > --- a/xen-hvm.c
> > > +++ b/xen-hvm.c
> > > @@ -1067,6 +1067,11 @@ int xen_hvm_init(ram_addr_t
> > *below_4g_mem_size, ram_addr_t *above_4g_mem_size,
> > > int i, rc;
> > > unsigned long ioreq_pfn;
> > > unsigned long bufioreq_evtchn;
> > > +
> > > +#ifdef CONFIG_TPM_XENSTUBDOMS
> > > + unsigned long stubdom_vtpm = 0;
> > > +#endif
> > > +
> > > XenIOState *state;
> > >
> > > state = g_malloc0(sizeof (XenIOState));
> > > @@ -1169,6 +1174,14 @@ int xen_hvm_init(ram_addr_t
> > *below_4g_mem_size, ram_addr_t *above_4g_mem_size,
> > > fprintf(stderr, "%s: xen backend core setup failed\n",
> > __FUNCTION__);
> > > return -1;
> > > }
> > > +
> > > +#ifdef CONFIG_TPM_XENSTUBDOMS
> > > + xc_get_hvm_param(xen_xc, xen_domid,
> > HVM_PARAM_STUBDOM_VTPM, &stubdom_vtpm);
> > > + if (stubdom_vtpm) {
> > > + xen_vtpm_register(&xen_vtpmdev_ops);
> > > + }
> > > +#endif
> >
> > Given that vtpm is just a PV frontend, can't you just detect whether is
> > present on xenstore and initialize it based on that? Like all the
> > backend below?
>
> Also I will explain in my next email.
>
>
> >
> >
> > > xen_be_register("console", &xen_console_ops);
> > > xen_be_register("vkbd", &xen_kbdmouse_ops);
> > > xen_be_register("qdisk", &xen_blkdev_ops);
> > > --
> > > 1.8.3.2
> > >
>
Re: [Qemu-devel] [PATCH 2/4] Qemu-Xen-vTPM: Register Xen stubdom vTPM frontend driver, Xu, Quan, 2014/11/06
Re: [Qemu-devel] [PATCH 2/4] Qemu-Xen-vTPM: Register Xen stubdom vTPM frontend driver, Paolo Bonzini, 2014/11/03