1.1 --- a/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c	Fri Mar 02 16:03:21 2007 +0000
     1.2 +++ b/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c	Fri Mar 02 16:15:28 2007 +0000
     1.3 @@ -113,14 +113,13 @@ void __exit tpmif_exit(void);
     1.4  
     1.5  
     1.6  static inline int
     1.7 -tx_buffer_copy(struct tx_buffer *txb, const u8 * src, int len,
     1.8 +tx_buffer_copy(struct tx_buffer *txb, const u8 *src, int len,
     1.9                 int isuserbuffer)
    1.10  {
    1.11  	int copied = len;
    1.12  
    1.13 -	if (len > txb->size) {
    1.14 +	if (len > txb->size)
    1.15  		copied = txb->size;
    1.16 -	}
    1.17  	if (isuserbuffer) {
    1.18  		if (copy_from_user(txb->data, src, copied))
    1.19  			return -EFAULT;
    1.20 @@ -133,18 +132,20 @@ tx_buffer_copy(struct tx_buffer *txb, co
    1.21  
    1.22  static inline struct tx_buffer *tx_buffer_alloc(void)
    1.23  {
    1.24 -	struct tx_buffer *txb = kzalloc(sizeof (struct tx_buffer),
    1.25 -					GFP_KERNEL);
    1.26 +	struct tx_buffer *txb;
    1.27 +
    1.28 +	txb = kzalloc(sizeof(struct tx_buffer), GFP_KERNEL);
    1.29 +	if (!txb)
    1.30 +		return NULL;
    1.31  
    1.32 -	if (txb) {
    1.33 -		txb->len = 0;
    1.34 -		txb->size = PAGE_SIZE;
    1.35 -		txb->data = (unsigned char *)__get_free_page(GFP_KERNEL);
    1.36 -		if (txb->data == NULL) {
    1.37 -			kfree(txb);
    1.38 -			txb = NULL;
    1.39 -		}
    1.40 +	txb->len = 0;
    1.41 +	txb->size = PAGE_SIZE;
    1.42 +	txb->data = (unsigned char *)__get_free_page(GFP_KERNEL);
    1.43 +	if (txb->data == NULL) {
    1.44 +		kfree(txb);
    1.45 +		txb = NULL;
    1.46  	}
    1.47 +
    1.48  	return txb;
    1.49  }
    1.50  
    1.51 @@ -160,37 +161,41 @@ static inline void tx_buffer_free(struct
    1.52  /**************************************************************
    1.53   Utility function for the tpm_private structure
    1.54  **************************************************************/
    1.55 -static inline void tpm_private_init(struct tpm_private *tp)
    1.56 +static void tpm_private_init(struct tpm_private *tp)
    1.57  {
    1.58  	spin_lock_init(&tp->tx_lock);
    1.59  	init_waitqueue_head(&tp->wait_q);
    1.60  	atomic_set(&tp->refcnt, 1);
    1.61  }
    1.62  
    1.63 -static inline void tpm_private_put(void)
    1.64 +static void tpm_private_put(void)
    1.65  {
    1.66 -	if ( atomic_dec_and_test(&my_priv->refcnt)) {
    1.67 -		tpmif_free_tx_buffers(my_priv);
    1.68 -		kfree(my_priv);
    1.69 -		my_priv = NULL;
    1.70 -	}
    1.71 +	if (!atomic_dec_and_test(&my_priv->refcnt))
    1.72 +		return;
    1.73 +
    1.74 +	tpmif_free_tx_buffers(my_priv);
    1.75 +	kfree(my_priv);
    1.76 +	my_priv = NULL;
    1.77  }
    1.78  
    1.79  static struct tpm_private *tpm_private_get(void)
    1.80  {
    1.81  	int err;
    1.82 -	if (!my_priv) {
    1.83 -		my_priv = kzalloc(sizeof(struct tpm_private), GFP_KERNEL);
    1.84 -		if (my_priv) {
    1.85 -			tpm_private_init(my_priv);
    1.86 -			err = tpmif_allocate_tx_buffers(my_priv);
    1.87 -			if (err < 0) {
    1.88 -				tpm_private_put();
    1.89 -			}
    1.90 -		}
    1.91 -	} else {
    1.92 +
    1.93 +	if (my_priv) {
    1.94  		atomic_inc(&my_priv->refcnt);
    1.95 +		return my_priv;
    1.96  	}
    1.97 +
    1.98 +	my_priv = kzalloc(sizeof(struct tpm_private), GFP_KERNEL);
    1.99 +	if (!my_priv)
   1.100 +		return NULL;
   1.101 +
   1.102 +	tpm_private_init(my_priv);
   1.103 +	err = tpmif_allocate_tx_buffers(my_priv);
   1.104 +	if (err < 0)
   1.105 +		tpm_private_put();
   1.106 +
   1.107  	return my_priv;
   1.108  }
   1.109  
   1.110 @@ -379,10 +384,8 @@ static int tpmfront_probe(struct xenbus_
   1.111  		return -ENOMEM;
   1.112  
   1.113  	tp->chip = init_vtpm(&dev->dev, &tvd, tp);
   1.114 -
   1.115 -	if (IS_ERR(tp->chip)) {
   1.116 +	if (IS_ERR(tp->chip))
   1.117  		return PTR_ERR(tp->chip);
   1.118 -	}
   1.119  
   1.120  	err = xenbus_scanf(XBT_NIL, dev->nodename,
   1.121  	                   "handle", "%i", &handle);
   1.122 @@ -401,6 +404,7 @@ static int tpmfront_probe(struct xenbus_
   1.123  		tpm_private_put();
   1.124  		return err;
   1.125  	}
   1.126 +
   1.127  	return 0;
   1.128  }
   1.129  
   1.130 @@ -417,7 +421,8 @@ static int tpmfront_suspend(struct xenbu
   1.131  {
   1.132  	struct tpm_private *tp = tpm_private_from_dev(&dev->dev);
   1.133  	u32 ctr;
   1.134 -	/* lock, so no app can send */
   1.135 +
   1.136 +	/* Take the lock, preventing any application from sending. */
   1.137  	mutex_lock(&suspend_lock);
   1.138  	tp->is_suspended = 1;
   1.139  
   1.140 @@ -425,19 +430,17 @@ static int tpmfront_suspend(struct xenbu
   1.141  		if ((ctr % 10) == 0)
   1.142  			printk("TPM-FE [INFO]: Waiting for outstanding "
   1.143  			       "request.\n");
   1.144 -		/*
   1.145 -		 * Wait for a request to be responded to.
   1.146 -		 */
   1.147 +		/* Wait for a request to be responded to. */
   1.148  		interruptible_sleep_on_timeout(&tp->wait_q, 100);
   1.149  	}
   1.150  
   1.151  	return 0;
   1.152  }
   1.153  
   1.154 -static int __tpmfront_suspend_cancel(struct tpm_private *tp)
   1.155 +static int tpmfront_resume(struct tpm_private *tp)
   1.156  {
   1.157  	tp->is_suspended = 0;
   1.158 -	/* unlock, so apps can send again */
   1.159 +	/* Allow applications to send again. */
   1.160  	mutex_unlock(&suspend_lock);
   1.161  	return 0;
   1.162  }
   1.163 @@ -445,7 +448,7 @@ static int __tpmfront_suspend_cancel(str
   1.164  static int tpmfront_suspend_cancel(struct xenbus_device *dev)
   1.165  {
   1.166  	struct tpm_private *tp = tpm_private_from_dev(&dev->dev);
   1.167 -	return __tpmfront_suspend_cancel(tp);
   1.168 +	return tpmfront_resume(tp);
   1.169  }
   1.170  
   1.171  static int tpmfront_resume(struct xenbus_device *dev)
   1.172 @@ -520,9 +523,8 @@ static void tpmif_free_tx_buffers(struct
   1.173  {
   1.174  	unsigned int i;
   1.175  
   1.176 -	for (i = 0; i < TPMIF_TX_RING_SIZE; i++) {
   1.177 +	for (i = 0; i < TPMIF_TX_RING_SIZE; i++)
   1.178  		tx_buffer_free(tp->tx_buffers[i]);
   1.179 -	}
   1.180  }
   1.181  
   1.182  static void tpmif_rx_action(unsigned long priv)
   1.183 @@ -542,9 +544,8 @@ static void tpmif_rx_action(unsigned lon
   1.184  	received = tx->size;
   1.185  
   1.186  	buffer = kmalloc(received, GFP_ATOMIC);
   1.187 -	if (NULL == buffer) {
   1.188 +	if (!buffer)
   1.189  		goto exit;
   1.190 -	}
   1.191  
   1.192  	for (i = 0; i < TPMIF_TX_RING_SIZE && offset < received; i++) {
   1.193  		struct tx_buffer *txb = tp->tx_buffers[i];
   1.194 @@ -553,9 +554,8 @@ static void tpmif_rx_action(unsigned lon
   1.195  
   1.196  		tx = &tp->tx->ring[i].req;
   1.197  		tocopy = tx->size;
   1.198 -		if (tocopy > PAGE_SIZE) {
   1.199 +		if (tocopy > PAGE_SIZE)
   1.200  			tocopy = PAGE_SIZE;
   1.201 -		}
   1.202  
   1.203  		memcpy(&buffer[offset], txb->data, tocopy);
   1.204  
   1.205 @@ -613,12 +613,13 @@ static int tpm_xmit(struct tpm_private *
   1.206  		struct tx_buffer *txb = tp->tx_buffers[i];
   1.207  		int copied;
   1.208  
   1.209 -		if (NULL == txb) {
   1.210 +		if (!txb) {
   1.211  			DPRINTK("txb (i=%d) is NULL. buffers initilized?\n"
   1.212  				"Not transmitting anything!\n", i);
   1.213  			spin_unlock_irq(&tp->tx_lock);
   1.214  			return -EFAULT;
   1.215  		}
   1.216 +
   1.217  		copied = tx_buffer_copy(txb, &buf[offset], count,
   1.218  		                        isuserbuffer);
   1.219  		if (copied < 0) {
   1.220 @@ -630,25 +631,26 @@ static int tpm_xmit(struct tpm_private *
   1.221  		offset += copied;
   1.222  
   1.223  		tx = &tp->tx->ring[i].req;
   1.224 -
   1.225  		tx->addr = virt_to_machine(txb->data);
   1.226  		tx->size = txb->len;
   1.227  
   1.228 -		DPRINTK("First 4 characters sent by TPM-FE are 0x%02x 0x%02x 0x%02x 0x%02x\n",
   1.229 +		DPRINTK("First 4 characters sent by TPM-FE are "
   1.230 +			"0x%02x 0x%02x 0x%02x 0x%02x\n",
   1.231  		        txb->data[0],txb->data[1],txb->data[2],txb->data[3]);
   1.232  
   1.233 -		/* get the granttable reference for this page */
   1.234 +		/* Get the granttable reference for this page. */
   1.235  		tx->ref = gnttab_claim_grant_reference(&gref_head);
   1.236 -
   1.237 -		if (-ENOSPC == tx->ref) {
   1.238 +		if (tx->ref == -ENOSPC) {
   1.239  			spin_unlock_irq(&tp->tx_lock);
   1.240 -			DPRINTK(" Grant table claim reference failed in func:%s line:%d file:%s\n", __FUNCTION__, __LINE__, __FILE__);
   1.241 +			DPRINTK("Grant table claim reference failed in "
   1.242 +				"func:%s line:%d file:%s\n",
   1.243 +				__FUNCTION__, __LINE__, __FILE__);
   1.244  			return -ENOSPC;
   1.245  		}
   1.246 -		gnttab_grant_foreign_access_ref( tx->ref,
   1.247 -		                                 tp->backend_id,
   1.248 -		                                 virt_to_mfn(txb->data),
   1.249 -		                                 0 /*RW*/);
   1.250 +		gnttab_grant_foreign_access_ref(tx->ref,
   1.251 +						tp->backend_id,
   1.252 +						virt_to_mfn(txb->data),
   1.253 +						0 /*RW*/);
   1.254  		wmb();
   1.255  	}
   1.256  
   1.257 @@ -666,15 +668,10 @@ static int tpm_xmit(struct tpm_private *
   1.258  
   1.259  static void tpmif_notify_upperlayer(struct tpm_private *tp)
   1.260  {
   1.261 -	/*
   1.262 -	 * Notify upper layer about the state of the connection
   1.263 -	 * to the BE.
   1.264 -	 */
   1.265 -	if (tp->is_connected) {
   1.266 -		vtpm_vd_status(tp->chip, TPM_VD_STATUS_CONNECTED);
   1.267 -	} else {
   1.268 -		vtpm_vd_status(tp->chip, TPM_VD_STATUS_DISCONNECTED);
   1.269 -	}
   1.270 +	/* Notify upper layer about the state of the connection to the BE. */
   1.271 +	vtpm_vd_status(tp->chip, (tp->is_connected
   1.272 +				  ? TPM_VD_STATUS_CONNECTED
   1.273 +				  : TPM_VD_STATUS_DISCONNECTED));
   1.274  }
   1.275  
   1.276  
   1.277 @@ -685,18 +682,16 @@ static void tpmif_set_connected_state(st
   1.278  	 * should disconnect - assumption is that we will resume
   1.279  	 * The mutex keeps apps from sending.
   1.280  	 */
   1.281 -	if (is_connected == 0 && tp->is_suspended == 1) {
   1.282 +	if (is_connected == 0 && tp->is_suspended == 1)
   1.283  		return;
   1.284 -	}
   1.285  
   1.286  	/*
   1.287  	 * Unlock the mutex if we are connected again
   1.288  	 * after being suspended - now resuming.
   1.289  	 * This also removes the suspend state.
   1.290  	 */
   1.291 -	if (is_connected == 1 && tp->is_suspended == 1) {
   1.292 -		__tpmfront_suspend_cancel(tp);
   1.293 -	}
   1.294 +	if (is_connected == 1 && tp->is_suspended == 1)
   1.295 +		tpmfront_resume(tp);
   1.296  
   1.297  	if (is_connected != tp->is_connected) {
   1.298  		tp->is_connected = is_connected;
   1.299 @@ -714,33 +709,24 @@ static void tpmif_set_connected_state(st
   1.300  
   1.301  static int __init tpmif_init(void)
   1.302  {
   1.303 -	long rc = 0;
   1.304  	struct tpm_private *tp;
   1.305  
   1.306  	if (is_initial_xendomain())
   1.307  		return -EPERM;
   1.308  
   1.309  	tp = tpm_private_get();
   1.310 -	if (!tp) {
   1.311 -		rc = -ENOMEM;
   1.312 -		goto failexit;
   1.313 -	}
   1.314 +	if (!tp)
   1.315 +		return -ENOMEM;
   1.316  
   1.317  	IPRINTK("Initialising the vTPM driver.\n");
   1.318 -	if ( gnttab_alloc_grant_references ( TPMIF_TX_RING_SIZE,
   1.319 -	                                     &gref_head ) < 0) {
   1.320 -		rc = -EFAULT;
   1.321 -		goto gnttab_alloc_failed;
   1.322 +	if (gnttab_alloc_grant_references(TPMIF_TX_RING_SIZE,
   1.323 +					  &gref_head) < 0) {
   1.324 +		tpm_private_put();
   1.325 +		return -EFAULT;
   1.326  	}
   1.327  
   1.328  	init_tpm_xenbus();
   1.329  	return 0;
   1.330 -
   1.331 -gnttab_alloc_failed:
   1.332 -	tpm_private_put();
   1.333 -failexit:
   1.334 -
   1.335 -	return (int)rc;
   1.336  }
   1.337  
   1.338