On 10/10/2016 08:51 AM, Jason Gunthorpe wrote:
> On Mon, Oct 10, 2016 at 07:23:33AM +0530, Nayna wrote:
>
>> And we pass this as private data to i_node in tpm_bios_log_setup.
>
>> So, we are referring chip as i_node->i_private->chip.
>
> That probably works, but you can't use the i_private = NULL scheme I
> outlined with that.
Why ? we are doing i_private = NULL during teardown to imply that chip
unregister is in progress. and no more securityfs operations should be
done. So, whether chip is NULL or securityfs_data is NULL, either should
be ok. Isn't it ?
Below is the open() function with NULL check and get_device().
put_device() I will do in release()
static int tpm_bios_measurements_open(struct inode *inode,
struct file *file)
{
int err;
struct seq_file *seq;
struct tpm_securityfs_data *sfs_data;
const struct seq_operations *seqops;
struct tpm_chip *chip;
inode_lock(inode);
if (!inode->i_private) { ---> This would be made NULL by teardown
inode_unlock(inode);
return -ENODEV;
}
sfs_data = (const struct tpm_securityfs_data *)inode->i_private;
seqops = sfs_data->seqops;
chip = sfs_data->chip;
get_device(&chip->dev);
/* now register seq file */
err = seq_open(file, seqops);
if (!err) {
seq = file->private_data;
seq->private = &chip->log;
}
inode_unlock(inode);
return err;
}
Let me know if I am missing something basic.
Thanks & Regards,
- Nayna
>
> Jason
>
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, SlashDot.org! http://sdm.link/slashdot
_______________________________________________
tpmdd-devel mailing list
tpmdd-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
