[8/9] xen/gntdev.c: Convert to use vm_insert_range
diff mbox series

Message ID 20190111151235.GA2836@jordon-HP-15-Notebook-PC
State New
Headers show
Series
  • Use vm_insert_range and vm_insert_range_buggy
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Commit Message

Souptick Joarder Jan. 11, 2019, 3:12 p.m. UTC
Convert to use vm_insert_range() to map range of kernel
memory to user vma.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
---
 drivers/xen/gntdev.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

Comments

Boris Ostrovsky Jan. 14, 2019, 11:27 p.m. UTC | #1
On 1/11/19 10:12 AM, Souptick Joarder wrote:
> Convert to use vm_insert_range() to map range of kernel
> memory to user vma.
>
> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

(although it would be good to mention in the commit that you are also
replacing count with vma_pages(vma), and why)


> ---
>  drivers/xen/gntdev.c | 16 ++++++----------
>  1 file changed, 6 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
> index b0b02a5..ca4acee 100644
> --- a/drivers/xen/gntdev.c
> +++ b/drivers/xen/gntdev.c
> @@ -1082,18 +1082,17 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
>  {
>  	struct gntdev_priv *priv = flip->private_data;
>  	int index = vma->vm_pgoff;
> -	int count = vma_pages(vma);
>  	struct gntdev_grant_map *map;
> -	int i, err = -EINVAL;
> +	int err = -EINVAL;
>  
>  	if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED))
>  		return -EINVAL;
>  
>  	pr_debug("map %d+%d at %lx (pgoff %lx)\n",
> -			index, count, vma->vm_start, vma->vm_pgoff);
> +			index, vma_pages(vma), vma->vm_start, vma->vm_pgoff);
>  
>  	mutex_lock(&priv->lock);
> -	map = gntdev_find_map_index(priv, index, count);
> +	map = gntdev_find_map_index(priv, index, vma_pages(vma));
>  	if (!map)
>  		goto unlock_out;
>  	if (use_ptemod && map->vma)
> @@ -1145,12 +1144,9 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
>  		goto out_put_map;
>  
>  	if (!use_ptemod) {
> -		for (i = 0; i < count; i++) {
> -			err = vm_insert_page(vma, vma->vm_start + i*PAGE_SIZE,
> -				map->pages[i]);
> -			if (err)
> -				goto out_put_map;
> -		}
> +		err = vm_insert_range(vma, map->pages, map->count);
> +		if (err)
> +			goto out_put_map;
>  	} else {
>  #ifdef CONFIG_X86
>  		/*
Souptick Joarder Jan. 15, 2019, 4:49 a.m. UTC | #2
On Tue, Jan 15, 2019 at 4:58 AM Boris Ostrovsky
<boris.ostrovsky@oracle.com> wrote:
>
> On 1/11/19 10:12 AM, Souptick Joarder wrote:
> > Convert to use vm_insert_range() to map range of kernel
> > memory to user vma.
> >
> > Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
>
> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
>
> (although it would be good to mention in the commit that you are also
> replacing count with vma_pages(vma), and why)

The original code was using count ( *count = vma_pages(vma)* )
which is same as this patch. Do I need capture it change log ?

>
>
> > ---
> >  drivers/xen/gntdev.c | 16 ++++++----------
> >  1 file changed, 6 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
> > index b0b02a5..ca4acee 100644
> > --- a/drivers/xen/gntdev.c
> > +++ b/drivers/xen/gntdev.c
> > @@ -1082,18 +1082,17 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
> >  {
> >       struct gntdev_priv *priv = flip->private_data;
> >       int index = vma->vm_pgoff;
> > -     int count = vma_pages(vma);
> >       struct gntdev_grant_map *map;
> > -     int i, err = -EINVAL;
> > +     int err = -EINVAL;
> >
> >       if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED))
> >               return -EINVAL;
> >
> >       pr_debug("map %d+%d at %lx (pgoff %lx)\n",
> > -                     index, count, vma->vm_start, vma->vm_pgoff);
> > +                     index, vma_pages(vma), vma->vm_start, vma->vm_pgoff);
> >
> >       mutex_lock(&priv->lock);
> > -     map = gntdev_find_map_index(priv, index, count);
> > +     map = gntdev_find_map_index(priv, index, vma_pages(vma));
> >       if (!map)
> >               goto unlock_out;
> >       if (use_ptemod && map->vma)
> > @@ -1145,12 +1144,9 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
> >               goto out_put_map;
> >
> >       if (!use_ptemod) {
> > -             for (i = 0; i < count; i++) {
> > -                     err = vm_insert_page(vma, vma->vm_start + i*PAGE_SIZE,
> > -                             map->pages[i]);
> > -                     if (err)
> > -                             goto out_put_map;
> > -             }
> > +             err = vm_insert_range(vma, map->pages, map->count);
> > +             if (err)
> > +                     goto out_put_map;
> >       } else {
> >  #ifdef CONFIG_X86
> >               /*
>
Boris Ostrovsky Jan. 15, 2019, 3:29 p.m. UTC | #3
On 1/14/19 11:49 PM, Souptick Joarder wrote:
> On Tue, Jan 15, 2019 at 4:58 AM Boris Ostrovsky
> <boris.ostrovsky@oracle.com> wrote:
>> On 1/11/19 10:12 AM, Souptick Joarder wrote:
>>> Convert to use vm_insert_range() to map range of kernel
>>> memory to user vma.
>>>
>>> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
>> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
>>
>> (although it would be good to mention in the commit that you are also
>> replacing count with vma_pages(vma), and why)
> The original code was using count ( *count = vma_pages(vma)* )
> which is same as this patch. Do I need capture it change log ?


I'd just say that because theoretically count might not be equal to
map->count we should use the latter as input to vm_insert_range().

Thanks.
-boris



>
>>
>>> ---
>>>  drivers/xen/gntdev.c | 16 ++++++----------
>>>  1 file changed, 6 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
>>> index b0b02a5..ca4acee 100644
>>> --- a/drivers/xen/gntdev.c
>>> +++ b/drivers/xen/gntdev.c
>>> @@ -1082,18 +1082,17 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
>>>  {
>>>       struct gntdev_priv *priv = flip->private_data;
>>>       int index = vma->vm_pgoff;
>>> -     int count = vma_pages(vma);
>>>       struct gntdev_grant_map *map;
>>> -     int i, err = -EINVAL;
>>> +     int err = -EINVAL;
>>>
>>>       if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED))
>>>               return -EINVAL;
>>>
>>>       pr_debug("map %d+%d at %lx (pgoff %lx)\n",
>>> -                     index, count, vma->vm_start, vma->vm_pgoff);
>>> +                     index, vma_pages(vma), vma->vm_start, vma->vm_pgoff);
>>>
>>>       mutex_lock(&priv->lock);
>>> -     map = gntdev_find_map_index(priv, index, count);
>>> +     map = gntdev_find_map_index(priv, index, vma_pages(vma));
>>>       if (!map)
>>>               goto unlock_out;
>>>       if (use_ptemod && map->vma)
>>> @@ -1145,12 +1144,9 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
>>>               goto out_put_map;
>>>
>>>       if (!use_ptemod) {
>>> -             for (i = 0; i < count; i++) {
>>> -                     err = vm_insert_page(vma, vma->vm_start + i*PAGE_SIZE,
>>> -                             map->pages[i]);
>>> -                     if (err)
>>> -                             goto out_put_map;
>>> -             }
>>> +             err = vm_insert_range(vma, map->pages, map->count);
>>> +             if (err)
>>> +                     goto out_put_map;
>>>       } else {
>>>  #ifdef CONFIG_X86
>>>               /*

Patch
diff mbox series

diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index b0b02a5..ca4acee 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -1082,18 +1082,17 @@  static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
 {
 	struct gntdev_priv *priv = flip->private_data;
 	int index = vma->vm_pgoff;
-	int count = vma_pages(vma);
 	struct gntdev_grant_map *map;
-	int i, err = -EINVAL;
+	int err = -EINVAL;
 
 	if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED))
 		return -EINVAL;
 
 	pr_debug("map %d+%d at %lx (pgoff %lx)\n",
-			index, count, vma->vm_start, vma->vm_pgoff);
+			index, vma_pages(vma), vma->vm_start, vma->vm_pgoff);
 
 	mutex_lock(&priv->lock);
-	map = gntdev_find_map_index(priv, index, count);
+	map = gntdev_find_map_index(priv, index, vma_pages(vma));
 	if (!map)
 		goto unlock_out;
 	if (use_ptemod && map->vma)
@@ -1145,12 +1144,9 @@  static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
 		goto out_put_map;
 
 	if (!use_ptemod) {
-		for (i = 0; i < count; i++) {
-			err = vm_insert_page(vma, vma->vm_start + i*PAGE_SIZE,
-				map->pages[i]);
-			if (err)
-				goto out_put_map;
-		}
+		err = vm_insert_range(vma, map->pages, map->count);
+		if (err)
+			goto out_put_map;
 	} else {
 #ifdef CONFIG_X86
 		/*