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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH v2] add xen-tpmfront.ko: Xen Virtual TPM frontend driver
This patch ports the xen vtpm frontend driver for linux
from the linux-2.6.18-xen.hg tree to linux-stable. This
driver is designed be used with the mini-os tpmback driver
in Xen as part of the new mini-os virtual tpm subsystem.
See docs/misc/vtpm.txt in Xen and the xen-devel mailing list
for details.
Signed-off-by: Matthew Fioravante <matthew.fioravante@xxxxxxxxxx>
---
drivers/char/tpm/Kconfig | 11 +
drivers/char/tpm/Makefile | 2 +
drivers/char/tpm/tpm.h | 10 +
drivers/char/tpm/xen-tpmfront_if.c | 688 ++++++++++++++++++++++++++++++++++
drivers/char/tpm/xen-tpmfront_vtpm.c | 543 +++++++++++++++++++++++++++
drivers/char/tpm/xen-tpmfront_vtpm.h | 55 +++
include/xen/interface/io/tpmif.h | 65 ++++
7 files changed, 1374 insertions(+)
create mode 100644 drivers/char/tpm/xen-tpmfront_if.c
create mode 100644 drivers/char/tpm/xen-tpmfront_vtpm.c
create mode 100644 drivers/char/tpm/xen-tpmfront_vtpm.h
create mode 100644 include/xen/interface/io/tpmif.h
diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
index 915875e..23d272f 100644
--- a/drivers/char/tpm/Kconfig
+++ b/drivers/char/tpm/Kconfig
@@ -81,4 +81,15 @@ config TCG_IBMVTPM
will be accessible from within Linux. To compile this driver
as a module, choose M here; the module will be called tpm_ibmvtpm.
+config TCG_XEN
+ tristate "XEN TPM Interface"
+ depends on TCG_TPM && XEN
+ ---help---
+ If you want to make TPM support available to a Xen user domain,
+ say Yes and it will be accessible from within Linux. See
+ the manpages for xl, xl.conf, and docs/misc/vtpm.txt in
+ the Xen source repository for more details.
+ To compile this driver as a module, choose M here; the module
+ will be called xen-tpmfront.
+
endif # TCG_TPM
diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index 5b3fc8b..0161f05 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -17,3 +17,5 @@ obj-$(CONFIG_TCG_NSC) += tpm_nsc.o
obj-$(CONFIG_TCG_ATMEL) += tpm_atmel.o
obj-$(CONFIG_TCG_INFINEON) += tpm_infineon.o
obj-$(CONFIG_TCG_IBMVTPM) += tpm_ibmvtpm.o
+obj-$(CONFIG_TCG_XEN) += xen-tpmfront.o
+xen-tpmfront-y = xen-tpmfront_if.o xen-tpmfront_vtpm.o
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 8ef7649..b575892 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -328,6 +328,16 @@ extern int tpm_pm_resume(struct device *);
extern int wait_for_tpm_stat(struct tpm_chip *, u8, unsigned long,
wait_queue_head_t *);
+static inline void *chip_get_private(const struct tpm_chip *chip)
+{
+ return chip->vendor.data;
+}
+
+static inline void chip_set_private(struct tpm_chip *chip, void *priv)
+{
+ chip->vendor.data = priv;
+}
+
#ifdef CONFIG_ACPI
extern int tpm_add_ppi(struct kobject *);
extern void tpm_remove_ppi(struct kobject *);
diff --git a/drivers/char/tpm/xen-tpmfront_if.c
b/drivers/char/tpm/xen-tpmfront_if.c
new file mode 100644
index 0000000..ba7fad8
--- /dev/null
+++ b/drivers/char/tpm/xen-tpmfront_if.c
@@ -0,0 +1,688 @@
+/*
+ * Copyright (c) 2005, IBM Corporation
+ *
+ * Author: Stefan Berger, stefanb@xxxxxxxxxx
+ * Grant table support: Mahadevan Gomathisankaran
+ *
+ * This code has been derived from drivers/xen/netfront/netfront.c
+ *
+ * Copyright (c) 2002-2004, K A Fraser
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/mutex.h>
+#include <linux/uaccess.h>
+#include <xen/events.h>
+#include <xen/interface/grant_table.h>
+#include <xen/interface/io/tpmif.h>
+#include <xen/grant_table.h>
+#include <xen/xenbus.h>
+#include <xen/page.h>
+#include "tpm.h"
+#include "xen-tpmfront_vtpm.h"
+
+#define GRANT_INVALID_REF 0
+
+/* local structures */
+struct tpm_private {
+ struct tpm_chip *chip;
+
+ struct tpmif_tx_interface *tx;
+ atomic_t refcnt;
+ unsigned int evtchn;
+ u8 is_connected;
+ u8 is_suspended;
+
+ spinlock_t tx_lock;
+
+ struct tx_buffer *tx_buffers[TPMIF_TX_RING_SIZE];
+
+ atomic_t tx_busy;
+ void *tx_remember;
+
+ domid_t backend_id;
+ wait_queue_head_t wait_q;
+
+ struct xenbus_device *dev;
+ int ring_ref;
+};
+
+struct tx_buffer {
+ unsigned int size; /* available space in data */
+ unsigned int len; /* used space in data */
+ unsigned char *data; /* pointer to a page */
+};
+
+
+/* locally visible variables */
+static grant_ref_t gref_head;
+static struct tpm_private *my_priv;
+
+/* local function prototypes */
+static irqreturn_t tpmif_int(int irq,
+ void *tpm_priv);
+static void tpmif_rx_action(unsigned long unused);
+static int tpmif_connect(struct xenbus_device *dev,
+ struct tpm_private *tp,
+ domid_t domid);
+static DECLARE_TASKLET(tpmif_rx_tasklet, tpmif_rx_action, 0);
+static int tpmif_allocate_tx_buffers(struct tpm_private *tp);
+static void tpmif_free_tx_buffers(struct tpm_private *tp);
+static void tpmif_set_connected_state(struct tpm_private *tp,
+ u8 newstate);
+static int tpm_xmit(struct tpm_private *tp,
+ const u8 *buf, size_t count, int userbuffer,
+ void *remember);
+static void destroy_tpmring(struct tpm_private *tp);
+
+static inline int
+tx_buffer_copy(struct tx_buffer *txb, const u8 *src, int len,
+ int isuserbuffer)
+{
+ int copied = len;
+
+ if (len > txb->size)
+ copied = txb->size;
+ if (isuserbuffer) {
+ if (copy_from_user(txb->data, src, copied))
+ return -EFAULT;
+ } else {
+ memcpy(txb->data, src, copied);
+ }
+ txb->len = len;
+ return copied;
+}
+
+static inline struct tx_buffer *tx_buffer_alloc(void)
+{
+ struct tx_buffer *txb;
+
+ txb = kzalloc(sizeof(struct tx_buffer), GFP_KERNEL);
+ if (!txb)
+ return NULL;
+
+ txb->len = 0;
+ txb->size = PAGE_SIZE;
+ txb->data = (unsigned char *)__get_free_page(GFP_KERNEL);
+ if (txb->data == NULL) {
+ kfree(txb);
+ txb = NULL;
+ }
+
+ return txb;
+}
+
+
+static inline void tx_buffer_free(struct tx_buffer *txb)
+{
+ if (txb) {
+ free_page((long)txb->data);
+ kfree(txb);
+ }
+}
+
+/**************************************************************
+ Utility function for the tpm_private structure
+ **************************************************************/
+static void tpm_private_init(struct tpm_private *tp)
+{
+ spin_lock_init(&tp->tx_lock);
+ init_waitqueue_head(&tp->wait_q);
+ atomic_set(&tp->refcnt, 1);
+}
+
+static void tpm_private_put(void)
+{
+ if (!atomic_dec_and_test(&my_priv->refcnt))
+ return;
+
+ tpmif_free_tx_buffers(my_priv);
+ kfree(my_priv);
+ my_priv = NULL;
+}
+
+static struct tpm_private *tpm_private_get(void)
+{
+ int err;
+
+ if (my_priv) {
+ atomic_inc(&my_priv->refcnt);
+ return my_priv;
+ }
+
+ my_priv = kzalloc(sizeof(struct tpm_private), GFP_KERNEL);
+ if (!my_priv)
+ return NULL;
+
+ tpm_private_init(my_priv);
+ err = tpmif_allocate_tx_buffers(my_priv);
+ if (err < 0)
+ tpm_private_put();
+
+ return my_priv;
+}
+
+/**************************************************************
+
+ The interface to let the tpm plugin register its callback
+ function and send data to another partition using this module
+
+ **************************************************************/
+
+static DEFINE_MUTEX(suspend_lock);
+/*
+ * Send data via this module by calling this function
+ */
+int vtpm_vd_send(struct tpm_private *tp,
+ const u8 *buf, size_t count, void *ptr)
+{
+ int sent;
+
+ mutex_lock(&suspend_lock);
+ sent = tpm_xmit(tp, buf, count, 0, ptr);
+ mutex_unlock(&suspend_lock);
+
+ return sent;
+}
+
+/**************************************************************
+ XENBUS support code
+ **************************************************************/
+
+static int setup_tpmring(struct xenbus_device *dev,
+ struct tpm_private *tp)
+{
+ struct tpmif_tx_interface *sring;
+ int err;
+
+ tp->ring_ref = GRANT_INVALID_REF;
+
+ sring = (void *)__get_free_page(GFP_KERNEL);
+ if (!sring) {
+ xenbus_dev_fatal(dev, -ENOMEM, "allocating shared ring");
+ return -ENOMEM;
+ }
+ tp->tx = sring;
+
+ err = xenbus_grant_ring(dev, virt_to_mfn(tp->tx));
+ if (err < 0) {
+ free_page((unsigned long)sring);
+ tp->tx = NULL;
+ xenbus_dev_fatal(dev, err, "allocating grant reference");
+ goto fail;
+ }
+ tp->ring_ref = err;
+
+ err = tpmif_connect(dev, tp, dev->otherend_id);
+ if (err)
+ goto fail;
+
+ return 0;
+fail:
+ destroy_tpmring(tp);
+ return err;
+}
+
+
+static void destroy_tpmring(struct tpm_private *tp)
+{
+ tpmif_set_connected_state(tp, 0);
+
+ if (tp->ring_ref != GRANT_INVALID_REF) {
+ gnttab_end_foreign_access(tp->ring_ref,
+ 0, (unsigned long)tp->tx);
+ tp->ring_ref = GRANT_INVALID_REF;
+ tp->tx = NULL;
+ }
+
+ if (tp->evtchn)
+ unbind_from_irqhandler(irq_from_evtchn(tp->evtchn), tp);
+
+ tp->evtchn = GRANT_INVALID_REF;
+}
+
+
+static int talk_to_backend(struct xenbus_device *dev,
+ struct tpm_private *tp)
+{
+ const char *message = NULL;
+ int err;
+ struct xenbus_transaction xbt;
+
+ err = setup_tpmring(dev, tp);
+ if (err) {
+ xenbus_dev_fatal(dev, err, "setting up ring");
+ goto out;
+ }
+
+again:
+ err = xenbus_transaction_start(&xbt);
+ if (err) {
+ xenbus_dev_fatal(dev, err, "starting transaction");
+ goto destroy_tpmring;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename,
+ "ring-ref", "%u", tp->ring_ref);
+ if (err) {
+ message = "writing ring-ref";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
+ tp->evtchn);
+ if (err) {
+ message = "writing event-channel";
+ goto abort_transaction;
+ }
+
+ err = xenbus_transaction_end(xbt, 0);
+ if (err == -EAGAIN)
+ goto again;
+ if (err) {
+ xenbus_dev_fatal(dev, err, "completing transaction");
+ goto destroy_tpmring;
+ }
+
+ xenbus_switch_state(dev, XenbusStateConnected);
+
+ return 0;
+
+abort_transaction:
+ xenbus_transaction_end(xbt, 1);
+ if (message)
+ xenbus_dev_error(dev, err, "%s", message);
+destroy_tpmring:
+ destroy_tpmring(tp);
+out:
+ return err;
+}
+
+/**
+ * Callback received when the backend's state changes.
+ */
+static void backend_changed(struct xenbus_device *dev,
+ enum xenbus_state backend_state)
+{
+ struct tpm_private *tp = tpm_private_from_dev(&dev->dev);
+
+ switch (backend_state) {
+ case XenbusStateInitialising:
+ case XenbusStateInitWait:
+ case XenbusStateInitialised:
+ case XenbusStateReconfiguring:
+ case XenbusStateReconfigured:
+ case XenbusStateUnknown:
+ break;
+
+ case XenbusStateConnected:
+ tpmif_set_connected_state(tp, 1);
+ break;
+
+ case XenbusStateClosing:
+ tpmif_set_connected_state(tp, 0);
+ xenbus_frontend_closed(dev);
+ break;
+
+ case XenbusStateClosed:
+ tpmif_set_connected_state(tp, 0);
+ if (tp->is_suspended == 0)
+ device_unregister(&dev->dev);
+ xenbus_frontend_closed(dev);
+ break;
+ }
+}
+
+static int tpmfront_probe(struct xenbus_device *dev,
+ const struct xenbus_device_id *id)
+{
+ int err;
+ int handle;
+ struct tpm_private *tp = tpm_private_get();
+
+ if (!tp)
+ return -ENOMEM;
+
+ tp->chip = init_vtpm(&dev->dev, tp);
+ if (IS_ERR(tp->chip))
+ return PTR_ERR(tp->chip);
+
+ err = xenbus_scanf(XBT_NIL, dev->nodename,
+ "handle", "%i", &handle);
+ if (XENBUS_EXIST_ERR(err))
+ return err;
+
+ if (err < 0) {
+ xenbus_dev_fatal(dev, err, "reading virtual-device");
+ return err;
+ }
+
+ tp->dev = dev;
+
+ err = talk_to_backend(dev, tp);
+ if (err) {
+ tpm_private_put();
+ return err;
+ }
+
+ return 0;
+}
+
+
+static int __devexit tpmfront_remove(struct xenbus_device *dev)
+{
+ struct tpm_private *tp = tpm_private_from_dev(&dev->dev);
+ destroy_tpmring(tp);
+ cleanup_vtpm(&dev->dev);
+ return 0;
+}
+
+static int tpmfront_suspend(struct xenbus_device *dev)
+{
+ struct tpm_private *tp = tpm_private_from_dev(&dev->dev);
+ u32 ctr;
+
+ /* Take the lock, preventing any application from sending. */
+ mutex_lock(&suspend_lock);
+ tp->is_suspended = 1;
+
+ for (ctr = 0; atomic_read(&tp->tx_busy); ctr++) {
+ /* Wait for a request to be responded to. */
+ interruptible_sleep_on_timeout(&tp->wait_q, 100);
+ }
+
+ return 0;
+}
+
+static int tpmfront_suspend_finish(struct tpm_private *tp)
+{
+ tp->is_suspended = 0;
+ /* Allow applications to send again. */
+ mutex_unlock(&suspend_lock);
+ return 0;
+}
+
+static int tpmfront_resume(struct xenbus_device *dev)
+{
+ struct tpm_private *tp = tpm_private_from_dev(&dev->dev);
+ destroy_tpmring(tp);
+ return talk_to_backend(dev, tp);
+}
+
+static int tpmif_connect(struct xenbus_device *dev,
+ struct tpm_private *tp,
+ domid_t domid)
+{
+ int err;
+
+ tp->backend_id = domid;
+ tp->evtchn = GRANT_INVALID_REF;
+
+ err = xenbus_alloc_evtchn(dev, &tp->evtchn);
+ if (err)
+ return err;
+
+ err = bind_evtchn_to_irqhandler(tp->evtchn, tpmif_int,
+ 0, "tpmif", tp);
+ if (err <= 0)
+ return err;
+
+ return 0;
+}
+
+static const struct xenbus_device_id tpmfront_ids[] = {
+ { "vtpm" },
+ { "" }
+};
+MODULE_ALIAS("xen:vtpm");
+
+static DEFINE_XENBUS_DRIVER(tpmfront, ,
+ .probe = tpmfront_probe,
+ .remove = __devexit_p(tpmfront_remove),
+ .resume = tpmfront_resume,
+ .otherend_changed = backend_changed,
+ .suspend = tpmfront_suspend,
+ );
+
+static int tpmif_allocate_tx_buffers(struct tpm_private *tp)
+{
+ unsigned int i;
+
+ for (i = 0; i < TPMIF_TX_RING_SIZE; i++) {
+ tp->tx_buffers[i] = tx_buffer_alloc();
+ if (!tp->tx_buffers[i]) {
+ tpmif_free_tx_buffers(tp);
+ return -ENOMEM;
+ }
+ }
+ return 0;
+}
+
+static void tpmif_free_tx_buffers(struct tpm_private *tp)
+{
+ unsigned int i;
+
+ for (i = 0; i < TPMIF_TX_RING_SIZE; i++)
+ tx_buffer_free(tp->tx_buffers[i]);
+}
+
+static void tpmif_rx_action(unsigned long priv)
+{
+ struct tpm_private *tp = (struct tpm_private *)priv;
+ int i = 0;
+ unsigned int received;
+ unsigned int offset = 0;
+ u8 *buffer;
+ struct tpmif_tx_request *tx = &tp->tx->ring[i].req;
+
+ atomic_set(&tp->tx_busy, 0);
+ wake_up_interruptible(&tp->wait_q);
+
+ received = tx->size;
+
+ buffer = kmalloc(received, GFP_ATOMIC);
+ if (!buffer)
+ return;
+
+ for (i = 0; i < TPMIF_TX_RING_SIZE && offset < received; i++) {
+ struct tx_buffer *txb = tp->tx_buffers[i];
+ struct tpmif_tx_request *tx;
+ unsigned int tocopy;
+
+ tx = &tp->tx->ring[i].req;
+ tocopy = tx->size;
+ if (tocopy > PAGE_SIZE)
+ tocopy = PAGE_SIZE;
+
+ memcpy(&buffer[offset], txb->data, tocopy);
+
+ gnttab_release_grant_reference(&gref_head, tx->ref);
+
+ offset += tocopy;
+ }
+
+ vtpm_vd_recv(tp->chip, buffer, received, tp->tx_remember);
+ kfree(buffer);
+}
+
+
+static irqreturn_t tpmif_int(int irq, void *tpm_priv)
+{
+ struct tpm_private *tp = tpm_priv;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tp->tx_lock, flags);
+ tpmif_rx_tasklet.data = (unsigned long)tp;
+ tasklet_schedule(&tpmif_rx_tasklet);
+ spin_unlock_irqrestore(&tp->tx_lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+
+static int tpm_xmit(struct tpm_private *tp,
+ const u8 *buf, size_t count, int isuserbuffer,
+ void *remember)
+{
+ struct tpmif_tx_request *tx;
+ int i;
+ unsigned int offset = 0;
+
+ spin_lock_irq(&tp->tx_lock);
+
+ if (unlikely(atomic_read(&tp->tx_busy))) {
+ spin_unlock_irq(&tp->tx_lock);
+ return -EBUSY;
+ }
+
+ if (tp->is_connected != 1) {
+ spin_unlock_irq(&tp->tx_lock);
+ return -EIO;
+ }
+
+ for (i = 0; count > 0 && i < TPMIF_TX_RING_SIZE; i++) {
+ struct tx_buffer *txb = tp->tx_buffers[i];
+ int copied;
+
+ if (!txb) {
+ spin_unlock_irq(&tp->tx_lock);
+ return -EFAULT;
+ }
+
+ copied = tx_buffer_copy(txb, &buf[offset], count,
+ isuserbuffer);
+ if (copied < 0) {
+ /* An error occurred */
+ spin_unlock_irq(&tp->tx_lock);
+ return copied;
+ }
+ count -= copied;
+ offset += copied;
+
+ tx = &tp->tx->ring[i].req;
+ tx->addr = virt_to_machine(txb->data).maddr;
+ tx->size = txb->len;
+ tx->unused = 0;
+
+ /* Get the granttable reference for this page. */
+ tx->ref = gnttab_claim_grant_reference(&gref_head);
+ if (tx->ref == -ENOSPC) {
+ spin_unlock_irq(&tp->tx_lock);
+ return -ENOSPC;
+ }
+ gnttab_grant_foreign_access_ref(tx->ref,
+ tp->backend_id,
+ virt_to_mfn(txb->data),
+ 0 /*RW*/);
+ wmb();
+ }
+
+ atomic_set(&tp->tx_busy, 1);
+ tp->tx_remember = remember;
+
+ mb();
+
+ notify_remote_via_evtchn(tp->evtchn);
+
+ spin_unlock_irq(&tp->tx_lock);
+ return offset;
+}
+
+
+static void tpmif_notify_upperlayer(struct tpm_private *tp)
+{
+ /* Notify upper layer about the state of the connection to the BE. */
+ vtpm_vd_status(tp->chip, (tp->is_connected
+ ? TPM_VD_STATUS_CONNECTED
+ : TPM_VD_STATUS_DISCONNECTED));
+}
+
+
+static void tpmif_set_connected_state(struct tpm_private *tp, u8 is_connected)
+{
+ /*
+ * Don't notify upper layer if we are in suspend mode and
+ * should disconnect - assumption is that we will resume
+ * The mutex keeps apps from sending.
+ */
+ if (is_connected == 0 && tp->is_suspended == 1)
+ return;
+
+ /*
+ * Unlock the mutex if we are connected again
+ * after being suspended - now resuming.
+ * This also removes the suspend state.
+ */
+ if (is_connected == 1 && tp->is_suspended == 1)
+ tpmfront_suspend_finish(tp);
+
+ if (is_connected != tp->is_connected) {
+ tp->is_connected = is_connected;
+ tpmif_notify_upperlayer(tp);
+ }
+}
+
+
+
+/* =================================================================
+ * Initialization function.
+ * =================================================================
+ */
+
+
+static int __init tpmif_init(void)
+{
+ struct tpm_private *tp;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ tp = tpm_private_get();
+ if (!tp)
+ return -ENOMEM;
+
+ if (gnttab_alloc_grant_references(TPMIF_TX_RING_SIZE,
+ &gref_head) < 0) {
+ tpm_private_put();
+ return -EFAULT;
+ }
+
+ return xenbus_register_frontend(&tpmfront_driver);
+}
+module_init(tpmif_init);
+
+static void __exit tpmif_exit(void)
+{
+ xenbus_unregister_driver(&tpmfront_driver);
+ gnttab_free_grant_references(gref_head);
+ tpm_private_put();
+}
+module_exit(tpmif_exit);
+
+MODULE_LICENSE("Dual BSD/GPL");
diff --git a/drivers/char/tpm/xen-tpmfront_vtpm.c
b/drivers/char/tpm/xen-tpmfront_vtpm.c
new file mode 100644
index 0000000..d70f1df
--- /dev/null
+++ b/drivers/char/tpm/xen-tpmfront_vtpm.c
@@ -0,0 +1,543 @@
+/*
+ * Copyright (C) 2006 IBM Corporation
+ *
+ * Authors:
+ * Stefan Berger <stefanb@xxxxxxxxxx>
+ *
+ * Generic device driver part for device drivers in a virtualized
+ * environment.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ */
+
+#include <linux/uaccess.h>
+#include <linux/list.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include "tpm.h"
+#include "xen-tpmfront_vtpm.h"
+
+/* read status bits */
+enum {
+ STATUS_BUSY = 0x01,
+ STATUS_DATA_AVAIL = 0x02,
+ STATUS_READY = 0x04
+};
+
+struct transmission {
+ struct list_head next;
+
+ unsigned char *request;
+ size_t request_len;
+ size_t request_buflen;
+
+ unsigned char *response;
+ size_t response_len;
+ size_t response_buflen;
+
+ unsigned int flags;
+};
+
+enum {
+ TRANSMISSION_FLAG_WAS_QUEUED = 0x1
+};
+
+
+enum {
+ DATAEX_FLAG_QUEUED_ONLY = 0x1
+};
+
+
+/* local variables */
+
+/* local function prototypes */
+static int _vtpm_send_queued(struct tpm_chip *chip);
+
+
+/* =============================================================
+ * Some utility functions
+ * =============================================================
+ */
+static void vtpm_state_init(struct vtpm_state *vtpms)
+{
+ vtpms->current_request = NULL;
+ spin_lock_init(&vtpms->req_list_lock);
+ init_waitqueue_head(&vtpms->req_wait_queue);
+ INIT_LIST_HEAD(&vtpms->queued_requests);
+
+ vtpms->current_response = NULL;
+ spin_lock_init(&vtpms->resp_list_lock);
+ init_waitqueue_head(&vtpms->resp_wait_queue);
+
+ vtpms->disconnect_time = jiffies;
+}
+
+
+static inline struct transmission *transmission_alloc(void)
+{
+ return kzalloc(sizeof(struct transmission), GFP_ATOMIC);
+}
+
+static unsigned char *
+transmission_set_req_buffer(struct transmission *t,
+ unsigned char *buffer, size_t len)
+{
+ if (t->request_buflen < len) {
+ kfree(t->request);
+ t->request = kmalloc(len, GFP_KERNEL);
+ if (!t->request) {
+ t->request_buflen = 0;
+ return NULL;
+ }
+ t->request_buflen = len;
+ }
+
+ memcpy(t->request, buffer, len);
+ t->request_len = len;
+
+ return t->request;
+}
+
+static unsigned char *
+transmission_set_res_buffer(struct transmission *t,
+ const unsigned char *buffer, size_t len)
+{
+ if (t->response_buflen < len) {
+ kfree(t->response);
+ t->response = kmalloc(len, GFP_ATOMIC);
+ if (!t->response) {
+ t->response_buflen = 0;
+ return NULL;
+ }
+ t->response_buflen = len;
+ }
+
+ memcpy(t->response, buffer, len);
+ t->response_len = len;
+
+ return t->response;
+}
+
+static inline void transmission_free(struct transmission *t)
+{
+ kfree(t->request);
+ kfree(t->response);
+ kfree(t);
+}
+
+/* =============================================================
+ * Interface with the lower layer driver
+ * =============================================================
+ */
+/*
+ * Lower layer uses this function to make a response available.
+ */
+int vtpm_vd_recv(const struct tpm_chip *chip,
+ const unsigned char *buffer, size_t count,
+ void *ptr)
+{
+ unsigned long flags;
+ int ret_size = 0;
+ struct transmission *t;
+ struct vtpm_state *vtpms;
+
+ vtpms = (struct vtpm_state *)chip_get_private(chip);
+
+ /*
+ * The list with requests must contain one request
+ * only and the element there must be the one that
+ * was passed to me from the front-end.
+ */
+ spin_lock_irqsave(&vtpms->resp_list_lock, flags);
+ if (vtpms->current_request != ptr) {
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+ return 0;
+ }
+ t = vtpms->current_request;
+ if (t) {
+ transmission_free(t);
+ vtpms->current_request = NULL;
+ }
+
+ t = transmission_alloc();
+ if (t) {
+ if (!transmission_set_res_buffer(t, buffer, count)) {
+ transmission_free(t);
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+ return -ENOMEM;
+ }
+ ret_size = count;
+ vtpms->current_response = t;
+ wake_up_interruptible(&vtpms->resp_wait_queue);
+ }
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+
+ return ret_size;
+}
+
+
+/*
+ * Lower layer indicates its status (connected/disconnected)
+ */
+void vtpm_vd_status(const struct tpm_chip *chip, u8 vd_status)
+{
+ struct vtpm_state *vtpms;
+
+ vtpms = (struct vtpm_state *)chip_get_private(chip);
+
+ vtpms->vd_status = vd_status;
+ if ((vtpms->vd_status & TPM_VD_STATUS_CONNECTED) == 0)
+ vtpms->disconnect_time = jiffies;
+}
+
+/* =============================================================
+ * Interface with the generic TPM driver
+ * =============================================================
+ */
+static int vtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+ int rc = 0;
+ unsigned long flags;
+ struct vtpm_state *vtpms;
+
+ vtpms = (struct vtpm_state *)chip_get_private(chip);
+
+ /*
+ * Check if the previous operation only queued the command
+ * In this case there won't be a response, so I just
+ * return from here and reset that flag. In any other
+ * case I should receive a response from the back-end.
+ */
+ spin_lock_irqsave(&vtpms->resp_list_lock, flags);
+ if ((vtpms->flags & DATAEX_FLAG_QUEUED_ONLY) != 0) {
+ vtpms->flags &= ~DATAEX_FLAG_QUEUED_ONLY;
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+ /*
+ * The first few commands (measurements) must be
+ * queued since it might not be possible to talk to the
+ * TPM, yet.
+ * Return a response of up to 30 '0's.
+ */
+
+ count = min_t(size_t, count, 30);
+ memset(buf, 0x0, count);
+ return count;
+ }
+ /*
+ * Check whether something is in the responselist and if
+ * there's nothing in the list wait for something to appear.
+ */
+
+ if (!vtpms->current_response) {
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+ interruptible_sleep_on_timeout(&vtpms->resp_wait_queue,
+ 1000);
+ spin_lock_irqsave(&vtpms->resp_list_lock, flags);
+ }
+
+ if (vtpms->current_response) {
+ struct transmission *t = vtpms->current_response;
+ vtpms->current_response = NULL;
+ rc = min(count, t->response_len);
+ memcpy(buf, t->response, rc);
+ transmission_free(t);
+ }
+
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+ return rc;
+}
+
+static int vtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+ int rc = 0;
+ unsigned long flags;
+ struct transmission *t = transmission_alloc();
+ struct vtpm_state *vtpms;
+
+ vtpms = (struct vtpm_state *)chip_get_private(chip);
+
+ if (!t)
+ return -ENOMEM;
+ /*
+ * If there's a current request, it must be the
+ * previous request that has timed out.
+ */
+ spin_lock_irqsave(&vtpms->req_list_lock, flags);
+ if (vtpms->current_request != NULL) {
+ dev_warn(chip->dev, "Sending although there is a request
outstanding.\n"
+ " Previous request must have timed
out.\n");
+ transmission_free(vtpms->current_request);
+ vtpms->current_request = NULL;
+ }
+ spin_unlock_irqrestore(&vtpms->req_list_lock, flags);
+
+ /*
+ * Queue the packet if the driver below is not
+ * ready, yet, or there is any packet already
+ * in the queue.
+ * If the driver below is ready, unqueue all
+ * packets first before sending our current
+ * packet.
+ * For each unqueued packet, except for the
+ * last (=current) packet, call the function
+ * tpm_xen_recv to wait for the response to come
+ * back.
+ */
+ if ((vtpms->vd_status & TPM_VD_STATUS_CONNECTED) == 0) {
+ if (time_after(jiffies,
+ vtpms->disconnect_time + HZ * 10)) {
+ rc = -ENOENT;
+ } else {
+ goto queue_it;
+ }
+ } else {
+ /*
+ * Send all queued packets.
+ */
+ if (_vtpm_send_queued(chip) == 0) {
+
+ vtpms->current_request = t;
+
+ rc = vtpm_vd_send(vtpms->tpm_private,
+ buf,
+ count,
+ t);
+ /*
+ * The generic TPM driver will call
+ * the function to receive the response.
+ */
+ if (rc < 0) {
+ vtpms->current_request = NULL;
+ goto queue_it;
+ }
+ } else {
+queue_it:
+ if (!transmission_set_req_buffer(t, buf, count)) {
+ transmission_free(t);
+ rc = -ENOMEM;
+ goto exit;
+ }
+ /*
+ * An error occurred. Don't event try
+ * to send the current request. Just
+ * queue it.
+ */
+ spin_lock_irqsave(&vtpms->req_list_lock, flags);
+ vtpms->flags |= DATAEX_FLAG_QUEUED_ONLY;
+ list_add_tail(&t->next, &vtpms->queued_requests);
+ spin_unlock_irqrestore(&vtpms->req_list_lock, flags);
+ }
+ }
+
+exit:
+ return rc;
+}
+
+
+/*
+ * Send all queued requests.
+ */
+static int _vtpm_send_queued(struct tpm_chip *chip)
+{
+ int rc;
+ int error = 0;
+ unsigned long flags;
+ unsigned char buffer[1];
+ struct vtpm_state *vtpms;
+ vtpms = (struct vtpm_state *)chip_get_private(chip);
+
+ spin_lock_irqsave(&vtpms->req_list_lock, flags);
+
+ while (!list_empty(&vtpms->queued_requests)) {
+ /*
+ * Need to dequeue them.
+ * Read the result into a dummy buffer.
+ */
+ struct transmission *qt = (struct transmission *)
+ vtpms->queued_requests.next;
+ list_del(&qt->next);
+ vtpms->current_request = qt;
+ spin_unlock_irqrestore(&vtpms->req_list_lock, flags);
+
+ rc = vtpm_vd_send(vtpms->tpm_private,
+ qt->request,
+ qt->request_len,
+ qt);
+
+ if (rc < 0) {
+ spin_lock_irqsave(&vtpms->req_list_lock, flags);
+ qt = vtpms->current_request;
+ if (qt != NULL) {
+ /*
+ * requeue it at the beginning
+ * of the list
+ */
+ list_add(&qt->next,
+ &vtpms->queued_requests);
+ }
+ vtpms->current_request = NULL;
+ error = 1;
+ break;
+ }
+ /*
+ * After this point qt is not valid anymore!
+ * It is freed when the front-end is delivering
+ * the data by calling tpm_recv
+ */
+ /*
+ * Receive response into provided dummy buffer
+ */
+ rc = vtpm_recv(chip, buffer, sizeof(buffer));
+ spin_lock_irqsave(&vtpms->req_list_lock, flags);
+ }
+
+ spin_unlock_irqrestore(&vtpms->req_list_lock, flags);
+
+ return error;
+}
+
+static void vtpm_cancel(struct tpm_chip *chip)
+{
+ unsigned long flags;
+ struct vtpm_state *vtpms = (struct vtpm_state *)chip_get_private(chip);
+
+ spin_lock_irqsave(&vtpms->resp_list_lock, flags);
+
+ if (!vtpms->current_response && vtpms->current_request) {
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+ interruptible_sleep_on(&vtpms->resp_wait_queue);
+ spin_lock_irqsave(&vtpms->resp_list_lock, flags);
+ }
+
+ if (vtpms->current_response) {
+ struct transmission *t = vtpms->current_response;
+ vtpms->current_response = NULL;
+ transmission_free(t);
+ }
+
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+}
+
+static u8 vtpm_status(struct tpm_chip *chip)
+{
+ u8 rc = 0;
+ unsigned long flags;
+ struct vtpm_state *vtpms;
+
+ vtpms = (struct vtpm_state *)chip_get_private(chip);
+
+ spin_lock_irqsave(&vtpms->resp_list_lock, flags);
+ /*
+ * Data are available if:
+ * - there's a current response
+ * - the last packet was queued only (this is fake, but necessary to
+ * get the generic TPM layer to call the receive function.)
+ */
+ if (vtpms->current_response ||
+ 0 != (vtpms->flags & DATAEX_FLAG_QUEUED_ONLY)) {
+ rc = STATUS_DATA_AVAIL;
+ } else if (!vtpms->current_response && !vtpms->current_request) {
+ rc = STATUS_READY;
+ }
+
+ spin_unlock_irqrestore(&vtpms->resp_list_lock, flags);
+ return rc;
+}
+
+static const struct file_operations vtpm_ops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .open = tpm_open,
+ .read = tpm_read,
+ .write = tpm_write,
+ .release = tpm_release,
+};
+
+static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
+static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
+static DEVICE_ATTR(enabled, S_IRUGO, tpm_show_enabled, NULL);
+static DEVICE_ATTR(active, S_IRUGO, tpm_show_active, NULL);
+static DEVICE_ATTR(owned, S_IRUGO, tpm_show_owned, NULL);
+static DEVICE_ATTR(temp_deactivated, S_IRUGO, tpm_show_temp_deactivated,
+ NULL);
+static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
+static DEVICE_ATTR(cancel, S_IWUSR | S_IWGRP, NULL, tpm_store_cancel);
+
+static struct attribute *vtpm_attrs[] = {
+ &dev_attr_pubek.attr,
+ &dev_attr_pcrs.attr,
+ &dev_attr_enabled.attr,
+ &dev_attr_active.attr,
+ &dev_attr_owned.attr,
+ &dev_attr_temp_deactivated.attr,
+ &dev_attr_caps.attr,
+ &dev_attr_cancel.attr,
+ NULL,
+};
+
+static struct attribute_group vtpm_attr_grp = { .attrs = vtpm_attrs };
+
+#define TPM_LONG_TIMEOUT (10 * 60 * HZ)
+
+static struct tpm_vendor_specific tpm_vtpm = {
+ .recv = vtpm_recv,
+ .send = vtpm_send,
+ .cancel = vtpm_cancel,
+ .status = vtpm_status,
+ .req_complete_mask = STATUS_BUSY | STATUS_DATA_AVAIL,
+ .req_complete_val = STATUS_DATA_AVAIL,
+ .req_canceled = STATUS_READY,
+ .attr_group = &vtpm_attr_grp,
+ .miscdev = {
+ .fops = &vtpm_ops,
+ },
+ .duration = {
+ TPM_LONG_TIMEOUT,
+ TPM_LONG_TIMEOUT,
+ TPM_LONG_TIMEOUT,
+ },
+};
+
+struct tpm_chip *init_vtpm(struct device *dev,
+ struct tpm_private *tp)
+{
+ long rc;
+ struct tpm_chip *chip;
+ struct vtpm_state *vtpms;
+
+ vtpms = kzalloc(sizeof(struct vtpm_state), GFP_KERNEL);
+ if (!vtpms)
+ return ERR_PTR(-ENOMEM);
+
+ vtpm_state_init(vtpms);
+ vtpms->tpm_private = tp;
+
+ chip = tpm_register_hardware(dev, &tpm_vtpm);
+ if (!chip) {
+ rc = -ENODEV;
+ goto err_free_mem;
+ }
+
+ chip_set_private(chip, vtpms);
+
+ return chip;
+
+err_free_mem:
+ kfree(vtpms);
+
+ return ERR_PTR(rc);
+}
+
+void cleanup_vtpm(struct device *dev)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ struct vtpm_state *vtpms = (struct vtpm_state *)chip_get_private(chip);
+ tpm_remove_hardware(dev);
+ kfree(vtpms);
+}
diff --git a/drivers/char/tpm/xen-tpmfront_vtpm.h
b/drivers/char/tpm/xen-tpmfront_vtpm.h
new file mode 100644
index 0000000..16cf323
--- /dev/null
+++ b/drivers/char/tpm/xen-tpmfront_vtpm.h
@@ -0,0 +1,55 @@
+#ifndef XEN_TPMFRONT_VTPM_H
+#define XEN_TPMFRONT_VTPM_H
+
+struct tpm_chip;
+struct tpm_private;
+
+struct vtpm_state {
+ struct transmission *current_request;
+ spinlock_t req_list_lock;
+ wait_queue_head_t req_wait_queue;
+
+ struct list_head queued_requests;
+
+ struct transmission *current_response;
+ spinlock_t resp_list_lock;
+ wait_queue_head_t resp_wait_queue;
+
+ u8 vd_status;
+ u8 flags;
+
+ unsigned long disconnect_time;
+
+ /*
+ * The following is a private structure of the underlying
+ * driver. It is passed as parameter in the send function.
+ */
+ struct tpm_private *tpm_private;
+};
+
+
+enum vdev_status {
+ TPM_VD_STATUS_DISCONNECTED = 0x0,
+ TPM_VD_STATUS_CONNECTED = 0x1
+};
+
+/* this function is called from tpm_vtpm.c */
+int vtpm_vd_send(struct tpm_private *tp,
+ const u8 *buf, size_t count, void *ptr);
+
+/* these functions are offered by tpm_vtpm.c */
+struct tpm_chip *init_vtpm(struct device *,
+ struct tpm_private *);
+void cleanup_vtpm(struct device *);
+int vtpm_vd_recv(const struct tpm_chip *chip,
+ const unsigned char *buffer, size_t count, void *ptr);
+void vtpm_vd_status(const struct tpm_chip *, u8 status);
+
+static inline struct tpm_private *tpm_private_from_dev(struct device *dev)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ struct vtpm_state *vtpms = (struct vtpm_state *)chip->vendor.data;
+ return vtpms->tpm_private;
+}
+
+#endif
diff --git a/include/xen/interface/io/tpmif.h b/include/xen/interface/io/tpmif.h
new file mode 100644
index 0000000..c9e7294
--- /dev/null
+++ b/include/xen/interface/io/tpmif.h
@@ -0,0 +1,65 @@
+/******************************************************************************
+ * tpmif.h
+ *
+ * TPM I/O interface for Xen guest OSes.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (c) 2005, IBM Corporation
+ *
+ * Author: Stefan Berger, stefanb@xxxxxxxxxx
+ * Grant table support: Mahadevan Gomathisankaran
+ *
+ * This code has been derived from tools/libxc/xen/io/netif.h
+ *
+ * Copyright (c) 2003-2004, Keir Fraser
+ */
+
+#ifndef __XEN_PUBLIC_IO_TPMIF_H__
+#define __XEN_PUBLIC_IO_TPMIF_H__
+
+#include "../grant_table.h"
+
+struct tpmif_tx_request {
+ unsigned long addr; /* Machine address of packet. */
+ grant_ref_t ref; /* grant table access reference */
+ uint16_t unused;
+ uint16_t size; /* Packet size in bytes. */
+};
+struct tpmif_tx_request;
+
+/*
+ * The TPMIF_TX_RING_SIZE defines the number of pages the
+ * front-end and backend can exchange (= size of array).
+ */
+#define TPMIF_TX_RING_SIZE 1
+
+/* This structure must fit in a memory page. */
+
+struct tpmif_ring {
+ struct tpmif_tx_request req;
+};
+struct tpmif_ring;
+
+struct tpmif_tx_interface {
+ struct tpmif_ring ring[TPMIF_TX_RING_SIZE];
+};
+struct tpmif_tx_interface;
+
+#endif
--
1.7.10.4
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