[v4,1/2] tpm: add ptr to the tpm_space struct to file_priv

Commit Message

Tadeusz Struk Aug. 7, 2018, 8:27 p.m. UTC

Add a ptr to struct tpm_space to the file_priv to have an easy
access to it in the async job without the need to allocate memory.
This also allows to consolidate of the write operations for
the two interfaces.

Tested-by: Philip Tricca <[e-mail]>
Signed-off-by: Tadeusz Struk <[e-mail]>
---
 drivers/char/tpm/tpm-dev-common.c |    8 +++++---
 drivers/char/tpm/tpm-dev.c        |   10 ++--------
 drivers/char/tpm/tpm-dev.h        |    5 +++--
 drivers/char/tpm/tpmrm-dev.c      |   14 ++------------
 4 files changed, 12 insertions(+), 25 deletions(-)


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Comments

Jarkko Sakkinen Aug. 10, 2018, 5:27 p.m. UTC | #1

On Tue, Aug 07, 2018 at 01:27:44PM -0700, Tadeusz Struk wrote:
> Add a ptr to struct tpm_space to the file_priv to have an easy
> access to it in the async job without the need to allocate memory.
> This also allows to consolidate of the write operations for
> the two interfaces.

I think the 2nd premise should be the priority and the first premise should
be removed as it is not needed in any possible way to justify the
change.

/Jarkko

Tadeusz Struk Aug. 10, 2018, 6:05 p.m. UTC | #2

On 08/10/2018 10:27 AM, Jarkko Sakkinen wrote:
> On Tue, Aug 07, 2018 at 01:27:44PM -0700, Tadeusz Struk wrote:
>> Add a ptr to struct tpm_space to the file_priv to have an easy
>> access to it in the async job without the need to allocate memory.
>> This also allows to consolidate of the write operations for
>> the two interfaces.
> 
> I think the 2nd premise should be the priority and the first premise should
> be removed as it is not needed in any possible way to justify the
> change.

Jarkko,
The main reason why the pointer to tpm_space struct was added to the
file_priv was to have access to space in the async job when it is enqueued
via the /dev/tpm<N> interface. Currently it is only available in tpmrm_priv.
Otherwise I would need to introduce yet another struct what would consist of
a ptr file_priv and a ptr to tpm_space and allocate it on every enqueue.
Much easier was to to it this way. The consolidation was only a side effect
of this so I think the description is correct.
Thanks,

Jarkko Sakkinen Aug. 10, 2018, 6:43 p.m. UTC | #3

On Fri, Aug 10, 2018 at 11:05:17AM -0700, Tadeusz Struk wrote:
> On 08/10/2018 10:27 AM, Jarkko Sakkinen wrote:
> > On Tue, Aug 07, 2018 at 01:27:44PM -0700, Tadeusz Struk wrote:
> >> Add a ptr to struct tpm_space to the file_priv to have an easy
> >> access to it in the async job without the need to allocate memory.
> >> This also allows to consolidate of the write operations for
> >> the two interfaces.
> > 
> > I think the 2nd premise should be the priority and the first premise should
> > be removed as it is not needed in any possible way to justify the
> > change.
> 
> Jarkko,
> The main reason why the pointer to tpm_space struct was added to the
> file_priv was to have access to space in the async job when it is enqueued
> via the /dev/tpm<N> interface. Currently it is only available in tpmrm_priv.
> Otherwise I would need to introduce yet another struct what would consist of
> a ptr file_priv and a ptr to tpm_space and allocate it on every enqueue.
> Much easier was to to it this way. The consolidation was only a side effect
> of this so I think the description is correct.
> Thanks,
> -- 
> Tadeusz

The less dependencies a commit has more easy it is for me pick up. Here
the consodilation is enough to accept the commit but with the current
commit message I cannot apply it without accepting the whole patch set.

/Jarkko

Patch

diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
index e4a04b2d3c32..f0c033b69b62 100644
--- a/drivers/char/tpm/tpm-dev-common.c
+++ b/drivers/char/tpm/tpm-dev-common.c
@@ -43,9 +43,11 @@  static void timeout_work(struct work_struct *work)
 }
 
 void tpm_common_open(struct file *file, struct tpm_chip *chip,
-		     struct file_priv *priv)
+		     struct file_priv *priv, struct tpm_space *space)
 {
 	priv->chip = chip;
+	priv->space = space;
+
 	mutex_init(&priv->buffer_mutex);
 	timer_setup(&priv->user_read_timer, user_reader_timeout, 0);
 	INIT_WORK(&priv->work, timeout_work);
@@ -79,7 +81,7 @@  ssize_t tpm_common_read(struct file *file, char __user *buf,
 }
 
 ssize_t tpm_common_write(struct file *file, const char __user *buf,
-			 size_t size, loff_t *off, struct tpm_space *space)
+			 size_t size, loff_t *off)
 {
 	struct file_priv *priv = file->private_data;
 	size_t in_size = size;
@@ -119,7 +121,7 @@  ssize_t tpm_common_write(struct file *file, const char __user *buf,
 		mutex_unlock(&priv->buffer_mutex);
 		return -EPIPE;
 	}
-	out_size = tpm_transmit(priv->chip, space, priv->data_buffer,
+	out_size = tpm_transmit(priv->chip, priv->space, priv->data_buffer,
 				sizeof(priv->data_buffer), 0);
 
 	tpm_put_ops(priv->chip);
diff --git a/drivers/char/tpm/tpm-dev.c b/drivers/char/tpm/tpm-dev.c
index ebd74ab5abef..98b9630c3a36 100644
--- a/drivers/char/tpm/tpm-dev.c
+++ b/drivers/char/tpm/tpm-dev.c
@@ -39,7 +39,7 @@  static int tpm_open(struct inode *inode, struct file *file)
 	if (priv == NULL)
 		goto out;
 
-	tpm_common_open(file, chip, priv);
+	tpm_common_open(file, chip, priv, NULL);
 
 	return 0;
 
@@ -48,12 +48,6 @@  static int tpm_open(struct inode *inode, struct file *file)
 	return -ENOMEM;
 }
 
-static ssize_t tpm_write(struct file *file, const char __user *buf,
-			 size_t size, loff_t *off)
-{
-	return tpm_common_write(file, buf, size, off, NULL);
-}
-
 /*
  * Called on file close
  */
@@ -73,6 +67,6 @@  const struct file_operations tpm_fops = {
 	.llseek = no_llseek,
 	.open = tpm_open,
 	.read = tpm_common_read,
-	.write = tpm_write,
+	.write = tpm_common_write,
 	.release = tpm_release,
 };
diff --git a/drivers/char/tpm/tpm-dev.h b/drivers/char/tpm/tpm-dev.h
index b24cfb4d3ee1..4048677bbd78 100644
--- a/drivers/char/tpm/tpm-dev.h
+++ b/drivers/char/tpm/tpm-dev.h
@@ -6,6 +6,7 @@ 
 
 struct file_priv {
 	struct tpm_chip *chip;
+	struct tpm_space *space;
 
 	/* Data passed to and from the tpm via the read/write calls */
 	size_t data_pending;
@@ -18,11 +19,11 @@  struct file_priv {
 };
 
 void tpm_common_open(struct file *file, struct tpm_chip *chip,
-		     struct file_priv *priv);
+		     struct file_priv *priv, struct tpm_space *space);
 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);
+			 size_t size, loff_t *off);
 void tpm_common_release(struct file *file, struct file_priv *priv);
 
 #endif
diff --git a/drivers/char/tpm/tpmrm-dev.c b/drivers/char/tpm/tpmrm-dev.c
index 1a0e97a5da5a..96006c6b9696 100644
--- a/drivers/char/tpm/tpmrm-dev.c
+++ b/drivers/char/tpm/tpmrm-dev.c
@@ -28,7 +28,7 @@  static int tpmrm_open(struct inode *inode, struct file *file)
 		return -ENOMEM;
 	}
 
-	tpm_common_open(file, chip, &priv->priv);
+	tpm_common_open(file, chip, &priv->priv, &priv->space);
 
 	return 0;
 }
@@ -45,21 +45,11 @@  static int tpmrm_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static ssize_t tpmrm_write(struct file *file, const char __user *buf,
-		   size_t size, loff_t *off)
-{
-	struct file_priv *fpriv = file->private_data;
-	struct tpmrm_priv *priv = container_of(fpriv, struct tpmrm_priv, priv);
-
-	return tpm_common_write(file, buf, size, off, &priv->space);
-}
-
 const struct file_operations tpmrm_fops = {
 	.owner = THIS_MODULE,
 	.llseek = no_llseek,
 	.open = tpmrm_open,
 	.read = tpm_common_read,
-	.write = tpmrm_write,
+	.write = tpm_common_write,
 	.release = tpmrm_release,
 };
-