diff mbox series

[v2] gfs2: Replace deprecated kmap_atomic() by kmap_local_page()

Message ID ZJk1XTtgLFxIcxzp@bu2204.myguest.virtualbox.org
State New
Headers
Series [v2] gfs2: Replace deprecated kmap_atomic() by kmap_local_page() |

Commit Message

Deepak R Varma June 26, 2023, 6:51 a.m. UTC 
  kmap_atomic() is deprecated in favor of kmap_local_{folio,page}().

Therefore, replace kmap_atomic() with kmap_local_page() in
gfs2_internal_read() and stuffed_readpage().

kmap_atomic() disables page-faults and preemption (the latter only for
!PREEMPT_RT kernels), However, the code within the mapping/un-mapping in
gfs2_internal_read() and stuffed_readpage() does not depend on the
above-mentioned side effects.

Therefore, a mere replacement of the old API with the new one is all that
is required (i.e., there is no need to explicitly add any calls to
pagefault_disable() and/or preempt_disable()).

Signed-off-by: Deepak R Varma <drv@mailo.com>
---
Note: The Patch is build tested only. I will be happy to run recommended testing
with some guidance if required.

Changes in v2:
   - Update patch description to correct the replacement function name from
     kmap_local_folio to kmap_local _page 


 fs/gfs2/aops.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Comments

Fabio M. De Francesco June 27, 2023, 11:41 a.m. UTC | #1 
On lunedì 26 giugno 2023 08:51:09 CEST Deepak R Varma wrote:
> kmap_atomic() is deprecated in favor of kmap_local_{folio,page}().
> 
> Therefore, replace kmap_atomic() with kmap_local_page() in
> gfs2_internal_read() and stuffed_readpage().
> 
> kmap_atomic() disables page-faults and preemption (the latter only for
> !PREEMPT_RT kernels), However, the code within the mapping/un-mapping in
> gfs2_internal_read() and stuffed_readpage() does not depend on the
> above-mentioned side effects.
> 
> Therefore, a mere replacement of the old API with the new one is all that
> is required (i.e., there is no need to explicitly add any calls to
> pagefault_disable() and/or preempt_disable()).
> 
> Signed-off-by: Deepak R Varma <drv@mailo.com>
> ---
> Note: The Patch is build tested only. I will be happy to run recommended
> testing with some guidance if required.
> 
> Changes in v2:
>    - Update patch description to correct the replacement function name from
>      kmap_local_folio to kmap_local _page

Ah, well done. I didn't note this with the comment on v1.
 
>  fs/gfs2/aops.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
> index 3b41542d6697..7bd92054d353 100644
> --- a/fs/gfs2/aops.c
> +++ b/fs/gfs2/aops.c
> @@ -432,10 +432,10 @@ static int stuffed_readpage(struct gfs2_inode *ip,
> struct page *page) if (error)
>  		return error;
> 
> -	kaddr = kmap_atomic(page);
> +	kaddr = kmap_local_page(page);
>  	memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
>  	memset(kaddr + dsize, 0, PAGE_SIZE - dsize);
> -	kunmap_atomic(kaddr);
> +	kunmap_local(kaddr);
>  	flush_dcache_page(page);
>  	brelse(dibh);
>  	SetPageUptodate(page);
> @@ -498,12 +498,12 @@ int gfs2_internal_read(struct gfs2_inode *ip, char 
*buf,
> loff_t *pos, continue;
>  			return PTR_ERR(page);
>  		}
> -		p = kmap_atomic(page);
> +		p = kmap_local_page(page);
>  		amt = size - copied;
>  		if (offset + size > PAGE_SIZE)
>  			amt = PAGE_SIZE - offset;
>  		memcpy(buf + copied, p + offset, amt);

As said in the comment on v1, the memcpy_from_page() helper is better suited 
here, unless you noted something that prevents its use and that I'm not able 
to see at the moment.

Thanks,

Fabio

> -		kunmap_atomic(p);
> +		kunmap_local(p);
>  		put_page(page);
>  		copied += amt;
>  		index++;
> --
> 2.34.1
Andreas Gruenbacher June 27, 2023, 1:45 p.m. UTC | #2 
On Mon, Jun 26, 2023 at 8:51 AM Deepak R Varma <drv@mailo.com> wrote:
> kmap_atomic() is deprecated in favor of kmap_local_{folio,page}().

I'll apply this, convert the remaining instances of kmap_atomic(), and
switch to memcpy_{from,to}_page() where appropriate.

Thanks,
Andreas

> Therefore, replace kmap_atomic() with kmap_local_page() in
> gfs2_internal_read() and stuffed_readpage().
>
> kmap_atomic() disables page-faults and preemption (the latter only for
> !PREEMPT_RT kernels), However, the code within the mapping/un-mapping in
> gfs2_internal_read() and stuffed_readpage() does not depend on the
> above-mentioned side effects.
>
> Therefore, a mere replacement of the old API with the new one is all that
> is required (i.e., there is no need to explicitly add any calls to
> pagefault_disable() and/or preempt_disable()).
>
> Signed-off-by: Deepak R Varma <drv@mailo.com>
> ---
> Note: The Patch is build tested only. I will be happy to run recommended testing
> with some guidance if required.
>
> Changes in v2:
>    - Update patch description to correct the replacement function name from
>      kmap_local_folio to kmap_local _page
>
>
>  fs/gfs2/aops.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
> index 3b41542d6697..7bd92054d353 100644
> --- a/fs/gfs2/aops.c
> +++ b/fs/gfs2/aops.c
> @@ -432,10 +432,10 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
>         if (error)
>                 return error;
>
> -       kaddr = kmap_atomic(page);
> +       kaddr = kmap_local_page(page);
>         memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
>         memset(kaddr + dsize, 0, PAGE_SIZE - dsize);
> -       kunmap_atomic(kaddr);
> +       kunmap_local(kaddr);
>         flush_dcache_page(page);
>         brelse(dibh);
>         SetPageUptodate(page);
> @@ -498,12 +498,12 @@ int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
>                                 continue;
>                         return PTR_ERR(page);
>                 }
> -               p = kmap_atomic(page);
> +               p = kmap_local_page(page);
>                 amt = size - copied;
>                 if (offset + size > PAGE_SIZE)
>                         amt = PAGE_SIZE - offset;
>                 memcpy(buf + copied, p + offset, amt);
> -               kunmap_atomic(p);
> +               kunmap_local(p);
>                 put_page(page);
>                 copied += amt;
>                 index++;
> --
> 2.34.1
>
>
>
Deepak R Varma June 27, 2023, 6:22 p.m. UTC | #3 
On Tue, Jun 27, 2023 at 03:45:20PM +0200, Andreas Gruenbacher wrote:
> On Mon, Jun 26, 2023 at 8:51 AM Deepak R Varma <drv@mailo.com> wrote:
> > kmap_atomic() is deprecated in favor of kmap_local_{folio,page}().
> 
> I'll apply this, convert the remaining instances of kmap_atomic(), and
> switch to memcpy_{from,to}_page() where appropriate.

Hello Andreas,
Thank you for your review. I am working on the other conversion opportunities
for this module and will send those in shortly.

Regards,
Deepak.

> 
> Thanks,
> Andreas
> 
> > Therefore, replace kmap_atomic() with kmap_local_page() in
> > gfs2_internal_read() and stuffed_readpage().
> >
> > kmap_atomic() disables page-faults and preemption (the latter only for
> > !PREEMPT_RT kernels), However, the code within the mapping/un-mapping in
> > gfs2_internal_read() and stuffed_readpage() does not depend on the
> > above-mentioned side effects.
> >
> > Therefore, a mere replacement of the old API with the new one is all that
> > is required (i.e., there is no need to explicitly add any calls to
> > pagefault_disable() and/or preempt_disable()).
> >
> > Signed-off-by: Deepak R Varma <drv@mailo.com>
> > ---
> > Note: The Patch is build tested only. I will be happy to run recommended testing
> > with some guidance if required.
> >
> > Changes in v2:
> >    - Update patch description to correct the replacement function name from
> >      kmap_local_folio to kmap_local _page
> >
> >
> >  fs/gfs2/aops.c | 8 ++++----
> >  1 file changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
> > index 3b41542d6697..7bd92054d353 100644
> > --- a/fs/gfs2/aops.c
> > +++ b/fs/gfs2/aops.c
> > @@ -432,10 +432,10 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
> >         if (error)
> >                 return error;
> >
> > -       kaddr = kmap_atomic(page);
> > +       kaddr = kmap_local_page(page);
> >         memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
> >         memset(kaddr + dsize, 0, PAGE_SIZE - dsize);
> > -       kunmap_atomic(kaddr);
> > +       kunmap_local(kaddr);
> >         flush_dcache_page(page);
> >         brelse(dibh);
> >         SetPageUptodate(page);
> > @@ -498,12 +498,12 @@ int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
> >                                 continue;
> >                         return PTR_ERR(page);
> >                 }
> > -               p = kmap_atomic(page);
> > +               p = kmap_local_page(page);
> >                 amt = size - copied;
> >                 if (offset + size > PAGE_SIZE)
> >                         amt = PAGE_SIZE - offset;
> >                 memcpy(buf + copied, p + offset, amt);
> > -               kunmap_atomic(p);
> > +               kunmap_local(p);
> >                 put_page(page);
> >                 copied += amt;
> >                 index++;
> > --
> > 2.34.1
> >
> >
> >
>
diff mbox series

Patch

diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 3b41542d6697..7bd92054d353 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -432,10 +432,10 @@  static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
 	if (error)
 		return error;
 
-	kaddr = kmap_atomic(page);
+	kaddr = kmap_local_page(page);
 	memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
 	memset(kaddr + dsize, 0, PAGE_SIZE - dsize);
-	kunmap_atomic(kaddr);
+	kunmap_local(kaddr);
 	flush_dcache_page(page);
 	brelse(dibh);
 	SetPageUptodate(page);
@@ -498,12 +498,12 @@  int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
 				continue;
 			return PTR_ERR(page);
 		}
-		p = kmap_atomic(page);
+		p = kmap_local_page(page);
 		amt = size - copied;
 		if (offset + size > PAGE_SIZE)
 			amt = PAGE_SIZE - offset;
 		memcpy(buf + copied, p + offset, amt);
-		kunmap_atomic(p);
+		kunmap_local(p);
 		put_page(page);
 		copied += amt;
 		index++;