tpm: Use container_of to locate the tpm_chip in tpm_open

misc_open sets the file->private_date to the misc_dev when calling
open. We can use container_of to go from the misc_dev back to the
tpm_chip.

Future clean ups will move tpm_open into a new file and this change
means we do not have to export the tpm_chip list.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Joel Schopp <jschopp@linux.vnet.ibm.com>
Reviewed-by: Peter Huewe <peterhuewe@gmx.de>
Acked-by: Ashley Lai <adlai@linux.vnet.ibm.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
This commit is contained in:
Jason Gunthorpe 2013-10-05 11:38:02 -06:00 committed by Peter Huewe
parent 6aff1fdc5d
commit 58c09e2133

View file

@ -1170,38 +1170,25 @@ EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
*/
int tpm_open(struct inode *inode, struct file *file)
{
int minor = iminor(inode);
struct tpm_chip *chip = NULL, *pos;
rcu_read_lock();
list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
if (pos->vendor.miscdev.minor == minor) {
chip = pos;
get_device(chip->dev);
break;
}
}
rcu_read_unlock();
if (!chip)
return -ENODEV;
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");
put_device(chip->dev);
return -EBUSY;
}
chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
if (chip->data_buffer == NULL) {
clear_bit(0, &chip->is_open);
put_device(chip->dev);
return -ENOMEM;
}
atomic_set(&chip->data_pending, 0);
file->private_data = chip;
get_device(chip->dev);
return 0;
}
EXPORT_SYMBOL_GPL(tpm_open);