Commit e3302e0d authored by Jason Gunthorpe's avatar Jason Gunthorpe Committed by Peter Huewe
Browse files

tpm: Make tpm-dev allocate a per-file structure 



This consolidates everything that is only used within tpm-dev.c
into tpm-dev.c and out of the publicly visible struct tpm_chip.

The per-file allocation lays the ground work for someday fixing the
strange forced O_EXCL behaviour of the current code.

Signed-off-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: default avatarJoel Schopp <jschopp@linux.vnet.ibm.com>
Reviewed-by: default avatarAshley Lai <adlai@linux.vnet.ibm.com>
Signed-off-by: default avatarPeter Huewe <peterhuewe@gmx.de>
parent 5f82e9f0

drivers/char/tpm/tpm-dev.c

+57 −43
Original line number Diff line number Diff line
@@ -22,21 +22,34 @@ 
#include <linux/uaccess.h>

#include "tpm.h"



struct file_priv {

	struct tpm_chip *chip;



	/* Data passed to and from the tpm via the read/write calls */

	atomic_t data_pending;

	struct mutex buffer_mutex;



	struct timer_list user_read_timer;      /* user needs to claim result */

	struct work_struct work;



	u8 data_buffer[TPM_BUFSIZE];

};



static void user_reader_timeout(unsigned long ptr)

{

	struct tpm_chip *chip = (struct tpm_chip *) ptr;

	struct file_priv *priv = (struct file_priv *)ptr;



	schedule_work(&chip->work);

	schedule_work(&priv->work);

}



static void timeout_work(struct work_struct *work)

{

	struct tpm_chip *chip = container_of(work, struct tpm_chip, work);

	struct file_priv *priv = container_of(work, struct file_priv, work);



	mutex_lock(&chip->buffer_mutex);

	atomic_set(&chip->data_pending, 0);

	memset(chip->data_buffer, 0, TPM_BUFSIZE);

	mutex_unlock(&chip->buffer_mutex);

	mutex_lock(&priv->buffer_mutex);

	atomic_set(&priv->data_pending, 0);

	memset(priv->data_buffer, 0, sizeof(priv->data_buffer));

	mutex_unlock(&priv->buffer_mutex);

}



static int tpm_open(struct inode *inode, struct file *file)
@@ -44,6 +57,7 @@ static int tpm_open(struct inode *inode, struct file *file) 
	struct miscdevice *misc = file->private_data;

	struct tpm_chip *chip = container_of(misc, struct tpm_chip,

					     vendor.miscdev);

	struct file_priv *priv;



	/* It's assured that the chip will be opened just once,

	 * by the check of is_open variable, which is protected
@@ -53,15 +67,20 @@ static int tpm_open(struct inode *inode, struct file *file) 
		return -EBUSY;

	}



	chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);

	if (chip->data_buffer == NULL) {

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);

	if (priv == NULL) {

		clear_bit(0, &chip->is_open);

		return -ENOMEM;

	}



	atomic_set(&chip->data_pending, 0);

	priv->chip = chip;

	atomic_set(&priv->data_pending, 0);

	mutex_init(&priv->buffer_mutex);

	setup_timer(&priv->user_read_timer, user_reader_timeout,

			(unsigned long)priv);

	INIT_WORK(&priv->work, timeout_work);



	file->private_data = chip;

	file->private_data = priv;

	get_device(chip->dev);

	return 0;

}
@@ -69,28 +88,28 @@ static int tpm_open(struct inode *inode, struct file *file) 
static ssize_t tpm_read(struct file *file, char __user *buf,

			size_t size, loff_t *off)

{

	struct tpm_chip *chip = file->private_data;

	struct file_priv *priv = file->private_data;

	ssize_t ret_size;

	int rc;



	del_singleshot_timer_sync(&chip->user_read_timer);

	flush_work(&chip->work);

	ret_size = atomic_read(&chip->data_pending);

	del_singleshot_timer_sync(&priv->user_read_timer);

	flush_work(&priv->work);

	ret_size = atomic_read(&priv->data_pending);

	if (ret_size > 0) {	/* relay data */

		ssize_t orig_ret_size = ret_size;

		if (size < ret_size)

			ret_size = size;



		mutex_lock(&chip->buffer_mutex);

		rc = copy_to_user(buf, chip->data_buffer, ret_size);

		memset(chip->data_buffer, 0, orig_ret_size);

		mutex_lock(&priv->buffer_mutex);

		rc = copy_to_user(buf, priv->data_buffer, ret_size);

		memset(priv->data_buffer, 0, orig_ret_size);

		if (rc)

			ret_size = -EFAULT;



		mutex_unlock(&chip->buffer_mutex);

		mutex_unlock(&priv->buffer_mutex);

	}



	atomic_set(&chip->data_pending, 0);

	atomic_set(&priv->data_pending, 0);



	return ret_size;

}
@@ -98,7 +117,7 @@ static ssize_t tpm_read(struct file *file, char __user *buf, 
static ssize_t tpm_write(struct file *file, const char __user *buf,

			 size_t size, loff_t *off)

{

	struct tpm_chip *chip = file->private_data;

	struct file_priv *priv = file->private_data;

	size_t in_size = size;

	ssize_t out_size;
@@ -106,32 +125,33 @@ static ssize_t tpm_write(struct file *file, const char __user *buf, 
	   either via tpm_read or a user_read_timer timeout.

	   This also prevents splitted buffered writes from blocking here.

	*/

	if (atomic_read(&chip->data_pending) != 0)

	if (atomic_read(&priv->data_pending) != 0)

		return -EBUSY;



	if (in_size > TPM_BUFSIZE)

		return -E2BIG;



	mutex_lock(&chip->buffer_mutex);

	mutex_lock(&priv->buffer_mutex);



	if (copy_from_user

	    (chip->data_buffer, (void __user *) buf, in_size)) {

		mutex_unlock(&chip->buffer_mutex);

	    (priv->data_buffer, (void __user *) buf, in_size)) {

		mutex_unlock(&priv->buffer_mutex);

		return -EFAULT;

	}



	/* atomic tpm command send and result receive */

	out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);

	out_size = tpm_transmit(priv->chip, priv->data_buffer,

				sizeof(priv->data_buffer));

	if (out_size < 0) {

		mutex_unlock(&chip->buffer_mutex);

		mutex_unlock(&priv->buffer_mutex);

		return out_size;

	}



	atomic_set(&chip->data_pending, out_size);

	mutex_unlock(&chip->buffer_mutex);

	atomic_set(&priv->data_pending, out_size);

	mutex_unlock(&priv->buffer_mutex);



	/* Set a timeout by which the reader must come claim the result */

	mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));

	mod_timer(&priv->user_read_timer, jiffies + (60 * HZ));



	return in_size;

}
@@ -141,15 +161,15 @@ static ssize_t tpm_write(struct file *file, const char __user *buf, 
 */

static int tpm_release(struct inode *inode, struct file *file)

{

	struct tpm_chip *chip = file->private_data;

	struct file_priv *priv = file->private_data;



	del_singleshot_timer_sync(&chip->user_read_timer);

	flush_work(&chip->work);

	del_singleshot_timer_sync(&priv->user_read_timer);

	flush_work(&priv->work);

	file->private_data = NULL;

	atomic_set(&chip->data_pending, 0);

	kzfree(chip->data_buffer);

	clear_bit(0, &chip->is_open);

	put_device(chip->dev);

	atomic_set(&priv->data_pending, 0);

	clear_bit(0, &priv->chip->is_open);

	put_device(priv->chip->dev);

	kfree(priv);

	return 0;

}
@@ -166,12 +186,6 @@ int tpm_dev_add_device(struct tpm_chip *chip) 
{

	int rc;



	mutex_init(&chip->buffer_mutex);

	INIT_WORK(&chip->work, timeout_work);



	setup_timer(&chip->user_read_timer, user_reader_timeout,

			(unsigned long)chip);



	chip->vendor.miscdev.fops = &tpm_fops;

	if (chip->dev_num == 0)

		chip->vendor.miscdev.minor = TPM_MINOR;

drivers/char/tpm/tpm.h

+0 −7
Original line number Diff line number Diff line
@@ -103,13 +103,6 @@ struct tpm_chip { 
	unsigned long is_open;	/* only one allowed */

	int time_expired;



	/* Data passed to and from the tpm via the read/write calls */

	u8 *data_buffer;

	atomic_t data_pending;

	struct mutex buffer_mutex;



	struct timer_list user_read_timer;	/* user needs to claim result */

	struct work_struct work;

	struct mutex tpm_mutex;	/* tpm is processing */



	struct tpm_vendor_specific vendor;

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