Re: [PATCH v2 5/7] tpm: split out tpm-dev.c into tpm-dev.c and tpm-common-dev.c

From: Jarkko Sakkinen
Date: Thu Feb 23 2017 - 04:08:12 EST

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On Thu, Feb 16, 2017 at 09:25:18PM +0200, Jarkko Sakkinen wrote:
> From: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
>
> Signed-off-by: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>

Reviewed-by: Jarkko Sakkinen <jarkko.sakkine@xxxxxxxxxxxxxxx>
Tested-by: Jarkko Sakkinen <jarkko.sakkine@xxxxxxxxxxxxxxx>

/Jarkko

> ---
> drivers/char/tpm/Makefile | 2 +-
> drivers/char/tpm/tpm-dev-common.c | 148 ++++++++++++++++++++++++++++++++++++++
> drivers/char/tpm/tpm-dev.c | 143 ++++--------------------------------
> drivers/char/tpm/tpm-dev.h | 27 +++++++
> 4 files changed, 190 insertions(+), 130 deletions(-)
> create mode 100644 drivers/char/tpm/tpm-dev-common.c
> create mode 100644 drivers/char/tpm/tpm-dev.h
>
> diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
> index 8f07fcf..10e5827 100644
> --- a/drivers/char/tpm/Makefile
> +++ b/drivers/char/tpm/Makefile
> @@ -3,7 +3,7 @@
> #
> obj-$(CONFIG_TCG_TPM) += tpm.o
> tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
> - tpm1_eventlog.o tpm2_eventlog.o tpm2-space.o
> + tpm-dev-common.o tpm1_eventlog.o tpm2_eventlog.o tpm2-space.o
> tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
> tpm-$(CONFIG_OF) += tpm_of.o
> obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
> diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
> new file mode 100644
> index 0000000..610638a
> --- /dev/null
> +++ b/drivers/char/tpm/tpm-dev-common.c
> @@ -0,0 +1,148 @@
> +/*
> + * Copyright (C) 2004 IBM Corporation
> + * Authors:
> + * Leendert van Doorn <leendert@xxxxxxxxxxxxxx>
> + * Dave Safford <safford@xxxxxxxxxxxxxx>
> + * Reiner Sailer <sailer@xxxxxxxxxxxxxx>
> + * Kylene Hall <kjhall@xxxxxxxxxx>
> + *
> + * Copyright (C) 2013 Obsidian Research Corp
> + * Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx>
> + *
> + * Device file system interface to the TPM
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation, version 2 of the
> + * License.
> + *
> + */
> +#include <linux/slab.h>
> +#include <linux/uaccess.h>
> +#include "tpm.h"
> +#include "tpm-dev.h"
> +
> +static void user_reader_timeout(unsigned long ptr)
> +{
> + struct file_priv *priv = (struct file_priv *)ptr;
> +
> + pr_warn("TPM user space timeout is deprecated (pid=%d)\n",
> + task_tgid_nr(current));
> +
> + schedule_work(&priv->work);
> +}
> +
> +static void timeout_work(struct work_struct *work)
> +{
> + struct file_priv *priv = container_of(work, struct file_priv, work);
> +
> + mutex_lock(&priv->buffer_mutex);
> + atomic_set(&priv->data_pending, 0);
> + memset(priv->data_buffer, 0, sizeof(priv->data_buffer));
> + mutex_unlock(&priv->buffer_mutex);
> +}
> +
> +void tpm_common_open(struct file *file, struct tpm_chip *chip,
> + struct file_priv *priv)
> +{
> + priv->chip = chip;
> + atomic_set(&priv->data_pending, 0);
> + mutex_init(&priv->buffer_mutex);
> + setup_timer(&priv->user_read_timer, user_reader_timeout,
> + (unsigned long)priv);
> + INIT_WORK(&priv->work, timeout_work);
> +
> + file->private_data = priv;
> +}
> +
> +ssize_t tpm_common_read(struct file *file, char __user *buf,
> + size_t size, loff_t *off)
> +{
> + struct file_priv *priv = file->private_data;
> + ssize_t ret_size;
> + ssize_t orig_ret_size;
> + int rc;
> +
> + del_singleshot_timer_sync(&priv->user_read_timer);
> + flush_work(&priv->work);
> + ret_size = atomic_read(&priv->data_pending);
> + if (ret_size > 0) { /* relay data */
> + orig_ret_size = ret_size;
> + if (size < ret_size)
> + ret_size = size;
> +
> + mutex_lock(&priv->buffer_mutex);
> + rc = copy_to_user(buf, priv->data_buffer, ret_size);
> + memset(priv->data_buffer, 0, orig_ret_size);
> + if (rc)
> + ret_size = -EFAULT;
> +
> + mutex_unlock(&priv->buffer_mutex);
> + }
> +
> + atomic_set(&priv->data_pending, 0);
> +
> + return ret_size;
> +}
> +
> +ssize_t tpm_common_write(struct file *file, const char __user *buf,
> + size_t size, loff_t *off, struct tpm_space *space)
> +{
> + struct file_priv *priv = 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 split
> + * buffered writes from blocking here.
> + */
> + if (atomic_read(&priv->data_pending) != 0)
> + return -EBUSY;
> +
> + if (in_size > TPM_BUFSIZE)
> + return -E2BIG;
> +
> + mutex_lock(&priv->buffer_mutex);
> +
> + if (copy_from_user
> + (priv->data_buffer, (void __user *) buf, in_size)) {
> + mutex_unlock(&priv->buffer_mutex);
> + return -EFAULT;
> + }
> +
> + /* atomic tpm command send and result receive. We only hold the ops
> + * lock during this period so that the tpm can be unregistered even if
> + * the char dev is held open.
> + */
> + if (tpm_try_get_ops(priv->chip)) {
> + mutex_unlock(&priv->buffer_mutex);
> + return -EPIPE;
> + }
> + out_size = tpm_transmit(priv->chip, space, priv->data_buffer,
> + sizeof(priv->data_buffer), 0);
> +
> + tpm_put_ops(priv->chip);
> + if (out_size < 0) {
> + mutex_unlock(&priv->buffer_mutex);
> + return out_size;
> + }
> +
> + atomic_set(&priv->data_pending, out_size);
> + mutex_unlock(&priv->buffer_mutex);
> +
> + /* Set a timeout by which the reader must come claim the result */
> + mod_timer(&priv->user_read_timer, jiffies + (120 * HZ));
> +
> + return in_size;
> +}
> +
> +/*
> + * Called on file close
> + */
> +void tpm_common_release(struct file *file, struct file_priv *priv)
> +{
> + del_singleshot_timer_sync(&priv->user_read_timer);
> + flush_work(&priv->work);
> + file->private_data = NULL;
> + atomic_set(&priv->data_pending, 0);
> +}
> diff --git a/drivers/char/tpm/tpm-dev.c b/drivers/char/tpm/tpm-dev.c
> index 414553b..ebd74ab 100644
> --- a/drivers/char/tpm/tpm-dev.c
> +++ b/drivers/char/tpm/tpm-dev.c
> @@ -18,48 +18,15 @@
> *
> */
> #include <linux/slab.h>
> -#include <linux/uaccess.h>
> -#include "tpm.h"
> -
> -struct file_priv {
> - struct tpm_chip *chip;
> -
> - /* Data passed to and from the tpm via the read/write calls */
> - atomic_t data_pending;
> - struct mutex buffer_mutex;
> -
> - struct timer_list user_read_timer; /* user needs to claim result */
> - struct work_struct work;
> -
> - u8 data_buffer[TPM_BUFSIZE];
> -};
> -
> -static void user_reader_timeout(unsigned long ptr)
> -{
> - struct file_priv *priv = (struct file_priv *)ptr;
> -
> - pr_warn("TPM user space timeout is deprecated (pid=%d)\n",
> - task_tgid_nr(current));
> -
> - schedule_work(&priv->work);
> -}
> -
> -static void timeout_work(struct work_struct *work)
> -{
> - struct file_priv *priv = container_of(work, struct file_priv, work);
> -
> - mutex_lock(&priv->buffer_mutex);
> - atomic_set(&priv->data_pending, 0);
> - memset(priv->data_buffer, 0, sizeof(priv->data_buffer));
> - mutex_unlock(&priv->buffer_mutex);
> -}
> +#include "tpm-dev.h"
>
> static int tpm_open(struct inode *inode, struct file *file)
> {
> - struct tpm_chip *chip =
> - container_of(inode->i_cdev, struct tpm_chip, cdev);
> + struct tpm_chip *chip;
> struct file_priv *priv;
>
> + chip = container_of(inode->i_cdev, struct tpm_chip, cdev);
> +
> /* It's assured that the chip will be opened just once,
> * by the check of is_open variable, which is protected
> * by driver_lock. */
> @@ -69,100 +36,22 @@ static int tpm_open(struct inode *inode, struct file *file)
> }
>
> priv = kzalloc(sizeof(*priv), GFP_KERNEL);
> - if (priv == NULL) {
> - clear_bit(0, &chip->is_open);
> - return -ENOMEM;
> - }
> + if (priv == NULL)
> + goto out;
>
> - priv->chip = chip;
> - atomic_set(&priv->data_pending, 0);
> - mutex_init(&priv->buffer_mutex);
> - setup_timer(&priv->user_read_timer, user_reader_timeout,
> - (unsigned long)priv);
> - INIT_WORK(&priv->work, timeout_work);
> + tpm_common_open(file, chip, priv);
>
> - file->private_data = priv;
> return 0;
> -}
> -
> -static ssize_t tpm_read(struct file *file, char __user *buf,
> - size_t size, loff_t *off)
> -{
> - struct file_priv *priv = file->private_data;
> - ssize_t ret_size;
> - int rc;
>
> - del_singleshot_timer_sync(&priv->user_read_timer);
> - flush_work(&priv->work);
> - ret_size = atomic_read(&priv->data_pending);
> - if (ret_size > 0) { /* relay data */
> - ssize_t orig_ret_size = ret_size;
> - if (size < ret_size)
> - ret_size = size;
> -
> - mutex_lock(&priv->buffer_mutex);
> - rc = copy_to_user(buf, priv->data_buffer, ret_size);
> - memset(priv->data_buffer, 0, orig_ret_size);
> - if (rc)
> - ret_size = -EFAULT;
> -
> - mutex_unlock(&priv->buffer_mutex);
> - }
> -
> - atomic_set(&priv->data_pending, 0);
> -
> - return ret_size;
> + out:
> + clear_bit(0, &chip->is_open);
> + return -ENOMEM;
> }
>
> static ssize_t tpm_write(struct file *file, const char __user *buf,
> size_t size, loff_t *off)
> {
> - struct file_priv *priv = 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(&priv->data_pending) != 0)
> - return -EBUSY;
> -
> - if (in_size > TPM_BUFSIZE)
> - return -E2BIG;
> -
> - mutex_lock(&priv->buffer_mutex);
> -
> - if (copy_from_user
> - (priv->data_buffer, (void __user *) buf, in_size)) {
> - mutex_unlock(&priv->buffer_mutex);
> - return -EFAULT;
> - }
> -
> - /* atomic tpm command send and result receive. We only hold the ops
> - * lock during this period so that the tpm can be unregistered even if
> - * the char dev is held open.
> - */
> - if (tpm_try_get_ops(priv->chip)) {
> - mutex_unlock(&priv->buffer_mutex);
> - return -EPIPE;
> - }
> - out_size = tpm_transmit(priv->chip, NULL, priv->data_buffer,
> - sizeof(priv->data_buffer), 0);
> -
> - tpm_put_ops(priv->chip);
> - if (out_size < 0) {
> - mutex_unlock(&priv->buffer_mutex);
> - return out_size;
> - }
> -
> - atomic_set(&priv->data_pending, out_size);
> - mutex_unlock(&priv->buffer_mutex);
> -
> - /* Set a timeout by which the reader must come claim the result */
> - mod_timer(&priv->user_read_timer, jiffies + (120 * HZ));
> -
> - return in_size;
> + return tpm_common_write(file, buf, size, off, NULL);
> }
>
> /*
> @@ -172,12 +61,10 @@ static int tpm_release(struct inode *inode, struct file *file)
> {
> struct file_priv *priv = file->private_data;
>
> - del_singleshot_timer_sync(&priv->user_read_timer);
> - flush_work(&priv->work);
> - file->private_data = NULL;
> - atomic_set(&priv->data_pending, 0);
> + tpm_common_release(file, priv);
> clear_bit(0, &priv->chip->is_open);
> kfree(priv);
> +
> return 0;
> }
>
> @@ -185,9 +72,7 @@ const struct file_operations tpm_fops = {
> .owner = THIS_MODULE,
> .llseek = no_llseek,
> .open = tpm_open,
> - .read = tpm_read,
> + .read = tpm_common_read,
> .write = tpm_write,
> .release = tpm_release,
> };
> -
> -
> diff --git a/drivers/char/tpm/tpm-dev.h b/drivers/char/tpm/tpm-dev.h
> new file mode 100644
> index 0000000..ff15cf7
> --- /dev/null
> +++ b/drivers/char/tpm/tpm-dev.h
> @@ -0,0 +1,27 @@
> +#ifndef _TPM_DEV_H
> +#define _TPM_DEV_H
> +
> +#include "tpm.h"
> +
> +struct file_priv {
> + struct tpm_chip *chip;
> +
> + /* Data passed to and from the tpm via the read/write calls */
> + atomic_t data_pending;
> + struct mutex buffer_mutex;
> +
> + struct timer_list user_read_timer; /* user needs to claim result */
> + struct work_struct work;
> +
> + u8 data_buffer[TPM_BUFSIZE];
> +};
> +
> +void tpm_common_open(struct file *file, struct tpm_chip *chip,
> + struct file_priv *priv);
> +ssize_t tpm_common_read(struct file *file, char __user *buf,
> + size_t size, loff_t *off);
> +ssize_t tpm_common_write(struct file *file, const char __user *buf,
> + size_t size, loff_t *off, struct tpm_space *space);
> +void tpm_common_release(struct file *file, struct file_priv *priv);
> +
> +#endif
> --
> 2.9.3
>
> --
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Next message: Jarkko Sakkinen: "Re: [PATCH v2 6/7] tpm: expose spaces via a device link /dev/tpms<n>"
Previous message: Mikko Perttunen: "Re: [PATCH 5/7] clk: tegra: don't warn for PLL defaults unnecessarily"
In reply to: Jarkko Sakkinen: "[PATCH v2 5/7] tpm: split out tpm-dev.c into tpm-dev.c and tpm-common-dev.c"
Next in thread: Jarkko Sakkinen: "[PATCH v2 3/7] tpm: export tpm2_flush_context_cmd"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]