Re: [PATCH v2 04/12] mini-os: use alloc_file_type() and get_file_from_fd() in tpm_tis

[Andrew Cooper <amc96@xxxxxxxx>]

On 11/01/2022 15:12, Juergen Gross wrote:
> diff --git a/tpm_tis.c b/tpm_tis.c
> index 477f555..abea7a1 100644
> --- a/tpm_tis.c
> +++ b/tpm_tis.c
> @@ -1093,6 +1097,23 @@ ssize_t tpm_getcap(struct tpm_chip *chip, uint32_t 
> subcap_id, cap_t *cap,
>          return rc;
>  }
>  
> +static void shutdown_tpm_tis(struct tpm_chip* tpm){

Style, as you're moving it.  Also in the function.

> @@ -1360,6 +1369,35 @@ int tpm_tis_posix_fstat(int fd, struct stat* buf)
>     return 0;
>  }
>  
> +static struct file_ops tpm_tis_ops = {
> +    .name = "tpm_tis",
> +    .read = tpm_tis_posix_read,
> +    .write = tpm_tis_posix_write,
> +    .lseek = lseek_default,
> +    .close = tpm_tis_close,
> +    .fstat = tpm_tis_posix_fstat,
> +};
> +
> +int tpm_tis_open(struct tpm_chip* tpm)

Style.

> +{
> +   struct file *file;
> +   static unsigned int ftype_tis;
> +
> +   /* Silently prevent multiple opens */
> +   if(tpm->fd != -1) {
> +      return tpm->fd;
> +   }

Another WTF moment.  We silently swallow multiple open()s, but don't
refcout close()s ?

This cannot be correct, or sensible, behaviour.

Jason/Daniel - thoughts?

~Andrew