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* Re: [PATCH -next] binder: simplify the return expression of binder_mmap
  2020-09-21  8:24 [PATCH -next] binder: simplify the return expression of binder_mmap Liu Shixin
@ 2020-09-21  8:08 ` Christian Brauner
  2020-09-21 10:42   ` Liu Shixin
  2020-09-21 11:47   ` Liu Shixin
  0 siblings, 2 replies; 9+ messages in thread
From: Christian Brauner @ 2020-09-21  8:08 UTC (permalink / raw)
  To: Liu Shixin
  Cc: Greg Kroah-Hartman, Arve Hjønnevåg, Todd Kjos,
	Martijn Coenen, Joel Fernandes, Christian Brauner,
	Hridya Valsaraju, Suren Baghdasaryan, devel, linux-kernel

On Mon, Sep 21, 2020 at 04:24:23PM +0800, Liu Shixin wrote:
> Simplify the return expression.
> 
> Signed-off-by: Liu Shixin <liushixin2@huawei.com>
> ---

Why not is all I can really say. :) But if this is about simplifying you
could get rid of the "ret" and "failure string" variables, and the goto
in that function completely by doing sm like this (__completely
untested__):

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index f936530a19b0..26f4dc81b008 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5182,9 +5182,7 @@ static const struct vm_operations_struct binder_vm_ops = {

 static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 {
-       int ret;
        struct binder_proc *proc = filp->private_data;
-       const char *failure_string;

        if (proc->tsk != current->group_leader)
                return -EINVAL;
@@ -5196,9 +5194,9 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
                     (unsigned long)pgprot_val(vma->vm_page_prot));

        if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
-               ret = -EPERM;
-               failure_string = "bad vm_flags";
-               goto err_bad_arg;
+               pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
+                               proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
+               return -EPERM;
        }
        vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP;
        vma->vm_flags &= ~VM_MAYWRITE;
@@ -5206,15 +5204,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
        vma->vm_ops = &binder_vm_ops;
        vma->vm_private_data = proc;

-       ret = binder_alloc_mmap_handler(&proc->alloc, vma);
-       if (ret)
-               return ret;
-       return 0;
-
-err_bad_arg:
-       pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
-              proc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
-       return ret;
+       return binder_alloc_mmap_handler(&proc->alloc, vma);
 }

Christian

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH -next] binder: simplify the return expression of binder_mmap
@ 2020-09-21  8:24 Liu Shixin
  2020-09-21  8:08 ` Christian Brauner
  0 siblings, 1 reply; 9+ messages in thread
From: Liu Shixin @ 2020-09-21  8:24 UTC (permalink / raw)
  To: Greg Kroah-Hartman, Arve Hjønnevåg, Todd Kjos,
	Martijn Coenen, Joel Fernandes, Christian Brauner,
	Hridya Valsaraju, Suren Baghdasaryan
  Cc: devel, linux-kernel, Liu Shixin

Simplify the return expression.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
---
 drivers/android/binder.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 37a505c41dec..1f929e0cf39f 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5204,10 +5204,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 	vma->vm_ops = &binder_vm_ops;
 	vma->vm_private_data = proc;
 
-	ret = binder_alloc_mmap_handler(&proc->alloc, vma);
-	if (ret)
-		return ret;
-	return 0;
+	return binder_alloc_mmap_handler(&proc->alloc, vma);
 
 err_bad_arg:
 	pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH -next] binder: simplify the return expression of binder_mmap
  2020-09-21  8:08 ` Christian Brauner
@ 2020-09-21 10:42   ` Liu Shixin
  2020-09-21 11:47   ` Liu Shixin
  1 sibling, 0 replies; 9+ messages in thread
From: Liu Shixin @ 2020-09-21 10:42 UTC (permalink / raw)
  To: Christian Brauner
  Cc: Greg Kroah-Hartman, Arve Hjønnevåg, Todd Kjos,
	Martijn Coenen, Joel Fernandes, Christian Brauner,
	Hridya Valsaraju, Suren Baghdasaryan, devel, linux-kernel

On 2020/9/21 16:08, Christian Brauner wrote:

> On Mon, Sep 21, 2020 at 04:24:23PM +0800, Liu Shixin wrote:
>> Simplify the return expression.
>>
>> Signed-off-by: Liu Shixin <liushixin2@huawei.com>
>> ---
> Why not is all I can really say. :) But if this is about simplifying you
> could get rid of the "ret" and "failure string" variables, and the goto
> in that function completely by doing sm like this (__completely
> untested__):

Thanks for your advice. I will modify and test it.

Regards,
Liu Shixin

>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index f936530a19b0..26f4dc81b008 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -5182,9 +5182,7 @@ static const struct vm_operations_struct binder_vm_ops = {
>
>  static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>  {
> -       int ret;
>         struct binder_proc *proc = filp->private_data;
> -       const char *failure_string;
>
>         if (proc->tsk != current->group_leader)
>                 return -EINVAL;
> @@ -5196,9 +5194,9 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>                      (unsigned long)pgprot_val(vma->vm_page_prot));
>
>         if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
> -               ret = -EPERM;
> -               failure_string = "bad vm_flags";
> -               goto err_bad_arg;
> +               pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
> +                               proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
> +               return -EPERM;
>         }
>         vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP;
>         vma->vm_flags &= ~VM_MAYWRITE;
> @@ -5206,15 +5204,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>         vma->vm_ops = &binder_vm_ops;
>         vma->vm_private_data = proc;
>
> -       ret = binder_alloc_mmap_handler(&proc->alloc, vma);
> -       if (ret)
> -               return ret;
> -       return 0;
> -
> -err_bad_arg:
> -       pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
> -              proc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
> -       return ret;
> +       return binder_alloc_mmap_handler(&proc->alloc, vma);
>  }
>
> Christian
> .
>


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH -next] binder: simplify the return expression of binder_mmap
  2020-09-21  8:08 ` Christian Brauner
  2020-09-21 10:42   ` Liu Shixin
@ 2020-09-21 11:47   ` Liu Shixin
  2020-09-27 12:35     ` Greg Kroah-Hartman
  1 sibling, 1 reply; 9+ messages in thread
From: Liu Shixin @ 2020-09-21 11:47 UTC (permalink / raw)
  To: Christian Brauner
  Cc: Greg Kroah-Hartman, Arve Hjønnevåg, Todd Kjos,
	Martijn Coenen, Joel Fernandes, Hridya Valsaraju,
	Suren Baghdasaryan, devel, linux-kernel, Liu Shixin

Simplify the return expression.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
---
 drivers/android/binder.c | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 37a505c41dec..49c0700816a5 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5180,9 +5180,7 @@ static const struct vm_operations_struct binder_vm_ops = {
 
 static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 {
-	int ret;
 	struct binder_proc *proc = filp->private_data;
-	const char *failure_string;
 
 	if (proc->tsk != current->group_leader)
 		return -EINVAL;
@@ -5194,9 +5192,9 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 		     (unsigned long)pgprot_val(vma->vm_page_prot));
 
 	if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
-		ret = -EPERM;
-		failure_string = "bad vm_flags";
-		goto err_bad_arg;
+		pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
+		       proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
+		return -EPERM;
 	}
 	vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP;
 	vma->vm_flags &= ~VM_MAYWRITE;
@@ -5204,15 +5202,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 	vma->vm_ops = &binder_vm_ops;
 	vma->vm_private_data = proc;
 
-	ret = binder_alloc_mmap_handler(&proc->alloc, vma);
-	if (ret)
-		return ret;
-	return 0;
-
-err_bad_arg:
-	pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
-	       proc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
-	return ret;
+	return binder_alloc_mmap_handler(&proc->alloc, vma);
 }
 
 static int binder_open(struct inode *nodp, struct file *filp)
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH -next] binder: simplify the return expression of binder_mmap
  2020-09-21 11:47   ` Liu Shixin
@ 2020-09-27 12:35     ` Greg Kroah-Hartman
  2020-09-29  1:52       ` [PATCH v3 " Liu Shixin
  0 siblings, 1 reply; 9+ messages in thread
From: Greg Kroah-Hartman @ 2020-09-27 12:35 UTC (permalink / raw)
  To: Liu Shixin
  Cc: Christian Brauner, devel, Todd Kjos, linux-kernel,
	Suren Baghdasaryan, Hridya Valsaraju, Arve Hjønnevåg,
	Joel Fernandes, Martijn Coenen

On Mon, Sep 21, 2020 at 07:47:34PM +0800, Liu Shixin wrote:
> Simplify the return expression.
> 
> Signed-off-by: Liu Shixin <liushixin2@huawei.com>
> ---
>  drivers/android/binder.c | 18 ++++--------------
>  1 file changed, 4 insertions(+), 14 deletions(-)

Is this a v2 patch?

If so, please properly label it and say what changed from the v1 version
below the --- line.

Please fix up and resend a v3.

thanks,

greg k-h

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH v3 -next] binder: simplify the return expression of binder_mmap
  2020-09-27 12:35     ` Greg Kroah-Hartman
@ 2020-09-29  1:52       ` Liu Shixin
  2020-10-02 13:48         ` Greg Kroah-Hartman
                           ` (2 more replies)
  0 siblings, 3 replies; 9+ messages in thread
From: Liu Shixin @ 2020-09-29  1:52 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Christian Brauner, Arve Hjønnevåg, Todd Kjos,
	Martijn Coenen, Joel Fernandes, Hridya Valsaraju,
	Suren Baghdasaryan, devel, linux-kernel, Liu Shixin

Simplify the return expression.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
---
v3: Add the change description.
v2: Get rid of the "ret" and "failure string" variables.
v1: Simplify the return expression.
---
 drivers/android/binder.c | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 37a505c41dec..49c0700816a5 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5180,9 +5180,7 @@ static const struct vm_operations_struct binder_vm_ops = {
 
 static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 {
-	int ret;
 	struct binder_proc *proc = filp->private_data;
-	const char *failure_string;
 
 	if (proc->tsk != current->group_leader)
 		return -EINVAL;
@@ -5194,9 +5192,9 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 		     (unsigned long)pgprot_val(vma->vm_page_prot));
 
 	if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
-		ret = -EPERM;
-		failure_string = "bad vm_flags";
-		goto err_bad_arg;
+		pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
+		       proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
+		return -EPERM;
 	}
 	vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP;
 	vma->vm_flags &= ~VM_MAYWRITE;
@@ -5204,15 +5202,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 	vma->vm_ops = &binder_vm_ops;
 	vma->vm_private_data = proc;
 
-	ret = binder_alloc_mmap_handler(&proc->alloc, vma);
-	if (ret)
-		return ret;
-	return 0;
-
-err_bad_arg:
-	pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
-	       proc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
-	return ret;
+	return binder_alloc_mmap_handler(&proc->alloc, vma);
 }
 
 static int binder_open(struct inode *nodp, struct file *filp)
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH v3 -next] binder: simplify the return expression of binder_mmap
  2020-09-29  1:52       ` [PATCH v3 " Liu Shixin
@ 2020-10-02 13:48         ` Greg Kroah-Hartman
  2020-10-02 14:18         ` Martijn Coenen
  2020-10-02 14:28         ` Christian Brauner
  2 siblings, 0 replies; 9+ messages in thread
From: Greg Kroah-Hartman @ 2020-10-02 13:48 UTC (permalink / raw)
  To: Liu Shixin
  Cc: devel, Todd Kjos, Suren Baghdasaryan, linux-kernel,
	Hridya Valsaraju, Arve Hjønnevåg, Joel Fernandes,
	Martijn Coenen, Christian Brauner

On Tue, Sep 29, 2020 at 09:52:16AM +0800, Liu Shixin wrote:
> Simplify the return expression.
> 
> Signed-off-by: Liu Shixin <liushixin2@huawei.com>
> ---
> v3: Add the change description.
> v2: Get rid of the "ret" and "failure string" variables.
> v1: Simplify the return expression.
> ---
>  drivers/android/binder.c | 18 ++++--------------
>  1 file changed, 4 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 37a505c41dec..49c0700816a5 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -5180,9 +5180,7 @@ static const struct vm_operations_struct binder_vm_ops = {
>  
>  static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>  {
> -	int ret;
>  	struct binder_proc *proc = filp->private_data;
> -	const char *failure_string;
>  
>  	if (proc->tsk != current->group_leader)
>  		return -EINVAL;
> @@ -5194,9 +5192,9 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>  		     (unsigned long)pgprot_val(vma->vm_page_prot));
>  
>  	if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
> -		ret = -EPERM;
> -		failure_string = "bad vm_flags";
> -		goto err_bad_arg;
> +		pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
> +		       proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
> +		return -EPERM;
>  	}
>  	vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP;
>  	vma->vm_flags &= ~VM_MAYWRITE;
> @@ -5204,15 +5202,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>  	vma->vm_ops = &binder_vm_ops;
>  	vma->vm_private_data = proc;
>  
> -	ret = binder_alloc_mmap_handler(&proc->alloc, vma);
> -	if (ret)
> -		return ret;
> -	return 0;
> -
> -err_bad_arg:
> -	pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
> -	       proc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
> -	return ret;
> +	return binder_alloc_mmap_handler(&proc->alloc, vma);
>  }
>  
>  static int binder_open(struct inode *nodp, struct file *filp)
> -- 
> 2.25.1

Todd and other Binder maintainers, what do you think of this?

thanks,

greg k-h

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH v3 -next] binder: simplify the return expression of binder_mmap
  2020-09-29  1:52       ` [PATCH v3 " Liu Shixin
  2020-10-02 13:48         ` Greg Kroah-Hartman
@ 2020-10-02 14:18         ` Martijn Coenen
  2020-10-02 14:28         ` Christian Brauner
  2 siblings, 0 replies; 9+ messages in thread
From: Martijn Coenen @ 2020-10-02 14:18 UTC (permalink / raw)
  To: Liu Shixin
  Cc: Greg Kroah-Hartman, Christian Brauner, Arve Hjønnevåg,
	Todd Kjos, Joel Fernandes, Hridya Valsaraju, Suren Baghdasaryan,
	open list:ANDROID DRIVERS, LKML

Thanks!

On Tue, Sep 29, 2020 at 3:30 AM Liu Shixin <liushixin2@huawei.com> wrote:
>
> Simplify the return expression.
>
> Signed-off-by: Liu Shixin <liushixin2@huawei.com>

Acked-by: Martijn Coenen <maco@android.com>

> ---
> v3: Add the change description.
> v2: Get rid of the "ret" and "failure string" variables.
> v1: Simplify the return expression.
> ---
>  drivers/android/binder.c | 18 ++++--------------
>  1 file changed, 4 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 37a505c41dec..49c0700816a5 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -5180,9 +5180,7 @@ static const struct vm_operations_struct binder_vm_ops = {
>
>  static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>  {
> -       int ret;
>         struct binder_proc *proc = filp->private_data;
> -       const char *failure_string;
>
>         if (proc->tsk != current->group_leader)
>                 return -EINVAL;
> @@ -5194,9 +5192,9 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>                      (unsigned long)pgprot_val(vma->vm_page_prot));
>
>         if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
> -               ret = -EPERM;
> -               failure_string = "bad vm_flags";
> -               goto err_bad_arg;
> +               pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
> +                      proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
> +               return -EPERM;
>         }
>         vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP;
>         vma->vm_flags &= ~VM_MAYWRITE;
> @@ -5204,15 +5202,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
>         vma->vm_ops = &binder_vm_ops;
>         vma->vm_private_data = proc;
>
> -       ret = binder_alloc_mmap_handler(&proc->alloc, vma);
> -       if (ret)
> -               return ret;
> -       return 0;
> -
> -err_bad_arg:
> -       pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
> -              proc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
> -       return ret;
> +       return binder_alloc_mmap_handler(&proc->alloc, vma);
>  }
>
>  static int binder_open(struct inode *nodp, struct file *filp)
> --
> 2.25.1
>

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH v3 -next] binder: simplify the return expression of binder_mmap
  2020-09-29  1:52       ` [PATCH v3 " Liu Shixin
  2020-10-02 13:48         ` Greg Kroah-Hartman
  2020-10-02 14:18         ` Martijn Coenen
@ 2020-10-02 14:28         ` Christian Brauner
  2 siblings, 0 replies; 9+ messages in thread
From: Christian Brauner @ 2020-10-02 14:28 UTC (permalink / raw)
  To: Liu Shixin
  Cc: Greg Kroah-Hartman, Christian Brauner, Arve Hjønnevåg,
	Todd Kjos, Martijn Coenen, Joel Fernandes, Hridya Valsaraju,
	Suren Baghdasaryan, devel, linux-kernel

On Tue, Sep 29, 2020 at 09:52:16AM +0800, Liu Shixin wrote:
> Simplify the return expression.
> 
> Signed-off-by: Liu Shixin <liushixin2@huawei.com>
> ---

Thanks!
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2020-10-02 14:28 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-09-21  8:24 [PATCH -next] binder: simplify the return expression of binder_mmap Liu Shixin
2020-09-21  8:08 ` Christian Brauner
2020-09-21 10:42   ` Liu Shixin
2020-09-21 11:47   ` Liu Shixin
2020-09-27 12:35     ` Greg Kroah-Hartman
2020-09-29  1:52       ` [PATCH v3 " Liu Shixin
2020-10-02 13:48         ` Greg Kroah-Hartman
2020-10-02 14:18         ` Martijn Coenen
2020-10-02 14:28         ` Christian Brauner

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