tpm: Pull everything related to /dev/tpmX into tpm-dev.c

CLASS-dev.c is a common idiom for Linux subsystems

This pulls all the code related to the miscdev into tpm-dev.c and makes it
static. The identical file_operation structs in the drivers are purged and the
tpm common code unconditionally creates the miscdev.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Joel Schopp <jschopp@linux.vnet.ibm.com>
Reviewed-by: Ashley Lai <adlai@linux.vnet.ibm.com>
[phuewe:
tpm_dev_release is now used only in this file, thus the EXPORT_SYMBOL
can be dropped and the function be marked as static.
It has no other in-kernel users]
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>

1 files changed, 12 insertions, 169 deletions

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 6ae41d337630..0b9e9ca05ef3 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -312,23 +312,6 @@ static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
 	TPM_MEDIUM,
 };
 
-static void user_reader_timeout(unsigned long ptr)
-{
-	struct tpm_chip *chip = (struct tpm_chip *) ptr;
-
-	schedule_work(&chip->work);
-}
-
-static void timeout_work(struct work_struct *work)
-{
-	struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
-
-	mutex_lock(&chip->buffer_mutex);
-	atomic_set(&chip->data_pending, 0);
-	memset(chip->data_buffer, 0, TPM_BUFSIZE);
-	mutex_unlock(&chip->buffer_mutex);
-}
-
 /*
  * Returns max number of jiffies to wait
  */
@@ -355,8 +338,8 @@ EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 /*
  * Internal kernel interface to transmit TPM commands
  */
-static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
-			    size_t bufsiz)
+ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
+		     size_t bufsiz)
 {
 	ssize_t rc;
 	u32 count, ordinal;
@@ -1151,127 +1134,6 @@ again:
 	return -ETIME;
 }
 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
-/*
- * Device file system interface to the TPM
- *
- * It's assured that the chip will be opened just once,
- * by the check of is_open variable, which is protected
- * by driver_lock.
- */
-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);
-
-	if (test_and_set_bit(0, &chip->is_open)) {
-		dev_dbg(chip->dev, "Another process owns this TPM\n");
-		return -EBUSY;
-	}
-
-	chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
-	if (chip->data_buffer == NULL) {
-		clear_bit(0, &chip->is_open);
-		return -ENOMEM;
-	}
-
-	atomic_set(&chip->data_pending, 0);
-
-	file->private_data = chip;
-	get_device(chip->dev);
-	return 0;
-}
-EXPORT_SYMBOL_GPL(tpm_open);
-
-/*
- * Called on file close
- */
-int tpm_release(struct inode *inode, struct file *file)
-{
-	struct tpm_chip *chip = file->private_data;
-
-	del_singleshot_timer_sync(&chip->user_read_timer);
-	flush_work(&chip->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);
-	return 0;
-}
-EXPORT_SYMBOL_GPL(tpm_release);
-
-ssize_t tpm_write(struct file *file, const char __user *buf,
-		  size_t size, loff_t *off)
-{
-	struct tpm_chip *chip = file->private_data;
-	size_t in_size = size;
-	ssize_t out_size;
-
-	/* cannot perform a write until the read has cleared
-	   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)
-		return -EBUSY;
-
-	if (in_size > TPM_BUFSIZE)
-		return -E2BIG;
-
-	mutex_lock(&chip->buffer_mutex);
-
-	if (copy_from_user
-	    (chip->data_buffer, (void __user *) buf, in_size)) {
-		mutex_unlock(&chip->buffer_mutex);
-		return -EFAULT;
-	}
-
-	/* atomic tpm command send and result receive */
-	out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
-	if (out_size < 0) {
-		mutex_unlock(&chip->buffer_mutex);
-		return out_size;
-	}
-
-	atomic_set(&chip->data_pending, out_size);
-	mutex_unlock(&chip->buffer_mutex);
-
-	/* Set a timeout by which the reader must come claim the result */
-	mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
-
-	return in_size;
-}
-EXPORT_SYMBOL_GPL(tpm_write);
-
-ssize_t tpm_read(struct file *file, char __user *buf,
-		 size_t size, loff_t *off)
-{
-	struct tpm_chip *chip = 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);
-	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);
-		if (rc)
-			ret_size = -EFAULT;
-
-		mutex_unlock(&chip->buffer_mutex);
-	}
-
-	atomic_set(&chip->data_pending, 0);
-
-	return ret_size;
-}
-EXPORT_SYMBOL_GPL(tpm_read);
 
 void tpm_remove_hardware(struct device *dev)
 {
@@ -1287,7 +1149,7 @@ void tpm_remove_hardware(struct device *dev)
 	spin_unlock(&driver_lock);
 	synchronize_rcu();
 
-	misc_deregister(&chip->vendor.miscdev);
+	tpm_dev_del_device(chip);
 	sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
 	tpm_remove_ppi(&dev->kobj);
 	tpm_bios_log_teardown(chip->bios_dir);
@@ -1448,7 +1310,7 @@ EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
  * Once all references to platform device are down to 0,
  * release all allocated structures.
  */
-void tpm_dev_release(struct device *dev)
+static void tpm_dev_release(struct device *dev)
 {
 	struct tpm_chip *chip = dev_get_drvdata(dev);
 
@@ -1460,7 +1322,6 @@ void tpm_dev_release(struct device *dev)
 	chip->release(dev);
 	kfree(chip);
 }
-EXPORT_SYMBOL_GPL(tpm_dev_release);
 
 /*
  * Called from tpm_<specific>.c probe function only for devices
@@ -1480,15 +1341,9 @@ struct tpm_chip *tpm_register_hardware(struct device *dev,
 	if (chip == NULL)
 		return NULL;
 
-	mutex_init(&chip->buffer_mutex);
 	mutex_init(&chip->tpm_mutex);
 	INIT_LIST_HEAD(&chip->list);
 
-	INIT_WORK(&chip->work, timeout_work);
-
-	setup_timer(&chip->user_read_timer, user_reader_timeout,
-			(unsigned long)chip);
-
 	memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
 
 	chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
@@ -1496,40 +1351,26 @@ struct tpm_chip *tpm_register_hardware(struct device *dev,
 	if (chip->dev_num >= TPM_NUM_DEVICES) {
 		dev_err(dev, "No available tpm device numbers\n");
 		goto out_free;
-	} else if (chip->dev_num == 0)
-		chip->vendor.miscdev.minor = TPM_MINOR;
-	else
-		chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
+	}
 
 	set_bit(chip->dev_num, dev_mask);
 
 	scnprintf(chip->devname, sizeof(chip->devname), "%s%d", "tpm",
 		  chip->dev_num);
-	chip->vendor.miscdev.name = chip->devname;
 
-	chip->vendor.miscdev.parent = dev;
 	chip->dev = get_device(dev);
 	chip->release = dev->release;
 	dev->release = tpm_dev_release;
 	dev_set_drvdata(dev, chip);
 
-	if (misc_register(&chip->vendor.miscdev)) {
-		dev_err(chip->dev,
-			"unable to misc_register %s, minor %d\n",
-			chip->vendor.miscdev.name,
-			chip->vendor.miscdev.minor);
+	if (tpm_dev_add_device(chip))
 		goto put_device;
-	}
 
-	if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
-		misc_deregister(&chip->vendor.miscdev);
-		goto put_device;
-	}
+	if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group))
+		goto del_misc;
 
-	if (tpm_add_ppi(&dev->kobj)) {
-		misc_deregister(&chip->vendor.miscdev);
-		goto put_device;
-	}
+	if (tpm_add_ppi(&dev->kobj))
+		goto del_misc;
 
 	chip->bios_dir = tpm_bios_log_setup(chip->devname);
 
@@ -1540,6 +1381,8 @@ struct tpm_chip *tpm_register_hardware(struct device *dev,
 
 	return chip;
 
+del_misc:
+	tpm_dev_del_device(chip);
 put_device:
 	put_device(chip->dev);
 out_free: