diff options
Diffstat (limited to 'linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c')
| -rw-r--r-- | linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c | 720 |
1 files changed, 0 insertions, 720 deletions
diff --git a/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c b/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c deleted file mode 100644 index 5488217463..0000000000 --- a/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c +++ /dev/null @@ -1,720 +0,0 @@ -/* - * Copyright (c) 2005, IBM Corporation - * - * Author: Stefan Berger, stefanb@us.ibm.com - * 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 <asm/uaccess.h> -#include <xen/evtchn.h> -#include <xen/interface/grant_table.h> -#include <xen/interface/io/tpmif.h> -#include <xen/gnttab.h> -#include <xen/xenbus.h> -#include "tpm.h" -#include "tpm_vtpm.h" - -#undef DEBUG - -/* local structures */ -struct tpm_private { - struct tpm_chip *chip; - - tpmif_tx_interface_t *tx; - atomic_t refcnt; - unsigned int irq; - 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, - struct pt_regs *ptregs); -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); -void __exit tpmif_exit(void); - -#define DPRINTK(fmt, args...) \ - pr_debug("xen_tpm_fr (%s:%d) " fmt, __FUNCTION__, __LINE__, ##args) -#define IPRINTK(fmt, args...) \ - printk(KERN_INFO "xen_tpm_fr: " fmt, ##args) -#define WPRINTK(fmt, args...) \ - printk(KERN_WARNING "xen_tpm_fr: " fmt, ##args) - -#define GRANT_INVALID_REF 0 - - -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) -{ - tpmif_tx_interface_t *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->irq) - unbind_from_irqhandler(tp->irq, tp); - - tp->irq = 0; -} - - -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", - irq_to_evtchn_port(tp->irq)); - 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); - DPRINTK("\n"); - - switch (backend_state) { - case XenbusStateInitialising: - case XenbusStateInitWait: - case XenbusStateInitialised: - 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 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++) { - if ((ctr % 10) == 0) - printk("TPM-FE [INFO]: Waiting for outstanding " - "request.\n"); - /* 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_suspend_cancel(struct xenbus_device *dev) -{ - struct tpm_private *tp = tpm_private_from_dev(&dev->dev); - return tpmfront_suspend_finish(tp); -} - -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; - - err = bind_listening_port_to_irqhandler( - domid, tpmif_int, SA_SAMPLE_RANDOM, "tpmif", tp); - if (err <= 0) { - WPRINTK("bind_listening_port_to_irqhandler failed " - "(err=%d)\n", err); - return err; - } - tp->irq = err; - - return 0; -} - -static struct xenbus_device_id tpmfront_ids[] = { - { "vtpm" }, - { "" } -}; - -static struct xenbus_driver tpmfront = { - .name = "vtpm", - .owner = THIS_MODULE, - .ids = tpmfront_ids, - .probe = tpmfront_probe, - .remove = tpmfront_remove, - .resume = tpmfront_resume, - .otherend_changed = backend_changed, - .suspend = tpmfront_suspend, - .suspend_cancel = tpmfront_suspend_cancel, -}; - -static void __init init_tpm_xenbus(void) -{ - xenbus_register_frontend(&tpmfront); -} - -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; - tpmif_tx_request_t *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]; - tpmif_tx_request_t *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 pt_regs *ptregs) -{ - 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) -{ - tpmif_tx_request_t *tx; - TPMIF_RING_IDX i; - unsigned int offset = 0; - - spin_lock_irq(&tp->tx_lock); - - if (unlikely(atomic_read(&tp->tx_busy))) { - printk("tpm_xmit: There's an outstanding request/response " - "on the way!\n"); - 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) { - DPRINTK("txb (i=%d) is NULL. buffers initilized?\n" - "Not transmitting anything!\n", i); - 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); - tx->size = txb->len; - - DPRINTK("First 4 characters sent by TPM-FE are " - "0x%02x 0x%02x 0x%02x 0x%02x\n", - txb->data[0],txb->data[1],txb->data[2],txb->data[3]); - - /* 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); - DPRINTK("Grant table claim reference failed in " - "func:%s line:%d file:%s\n", - __FUNCTION__, __LINE__, __FILE__); - 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_irq(tp->irq); - - 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 (is_initial_xendomain()) - return -EPERM; - - tp = tpm_private_get(); - if (!tp) - return -ENOMEM; - - IPRINTK("Initialising the vTPM driver.\n"); - if (gnttab_alloc_grant_references(TPMIF_TX_RING_SIZE, - &gref_head) < 0) { - tpm_private_put(); - return -EFAULT; - } - - init_tpm_xenbus(); - return 0; -} - - -module_init(tpmif_init); - -MODULE_LICENSE("Dual BSD/GPL"); |