drivers/char/tpm/tpmrm-dev.c

   1 /*
   2  * Copyright (C) 2017 James.Bottomley@HansenPartnership.com
   3  *
   4  * GPLv2
   5  */
   6 #include <linux/slab.h>
   7 #include "tpm-dev.h"
   8
   9 struct tpmrm_priv {
  10         struct file_priv priv;
  11         struct tpm_space space;
  12 };
  13
  14 static int tpmrm_open(struct inode *inode, struct file *file)
  15 {
  16         struct tpm_chip *chip;
  17         struct tpmrm_priv *priv;
  18         int rc;
  19
  20         chip = container_of(inode->i_cdev, struct tpm_chip, cdevs);
  21         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
  22         if (priv == NULL)
  23                 return -ENOMEM;
  24
  25         rc = tpm2_init_space(&priv->space, TPM2_SPACE_BUFFER_SIZE);
  26         if (rc) {
  27                 kfree(priv);
  28                 return -ENOMEM;
  29         }
  30
  31         tpm_common_open(file, chip, &priv->priv);
  32
  33         return 0;
  34 }
  35
  36 static int tpmrm_release(struct inode *inode, struct file *file)
  37 {
  38         struct file_priv *fpriv = file->private_data;
  39         struct tpmrm_priv *priv = container_of(fpriv, struct tpmrm_priv, priv);
  40
  41         tpm_common_release(file, fpriv);
  42         tpm2_del_space(fpriv->chip, &priv->space);
  43         kfree(priv);
  44
  45         return 0;
  46 }
  47
  48 static ssize_t tpmrm_write(struct file *file, const char __user *buf,
  49                    size_t size, loff_t *off)
  50 {
  51         struct file_priv *fpriv = file->private_data;
  52         struct tpmrm_priv *priv = container_of(fpriv, struct tpmrm_priv, priv);
  53
  54         return tpm_common_write(file, buf, size, off, &priv->space);
  55 }
  56
  57 const struct file_operations tpmrm_fops = {
  58         .owner = THIS_MODULE,
  59         .llseek = no_llseek,
  60         .open = tpmrm_open,
  61         .read = tpm_common_read,
  62         .write = tpmrm_write,
  63         .release = tpmrm_release,
  64 };
  65