[v6,5/6] ext4: disable map_sync for async flush
diff mbox series

Message ID 20190423080612.15361-6-pagupta@redhat.com
State Superseded
Headers show
Series
  • virtio pmem driver
Related show

Commit Message

Pankaj Gupta April 23, 2019, 8:06 a.m. UTC
Dont support 'MAP_SYNC' with non-DAX files and DAX files
with asynchronous dax_device. Virtio pmem provides 
asynchronous host page cache flush mechanism. We don't
support 'MAP_SYNC' with virtio pmem and ext4.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
---
 fs/ext4/file.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

Comments

Jan Kara April 23, 2019, 2:27 p.m. UTC | #1
On Tue 23-04-19 13:36:11, Pankaj Gupta wrote:
> Dont support 'MAP_SYNC' with non-DAX files and DAX files
> with asynchronous dax_device. Virtio pmem provides 
> asynchronous host page cache flush mechanism. We don't
> support 'MAP_SYNC' with virtio pmem and ext4.
> 
> Signed-off-by: Pankaj Gupta <pagupta@redhat.com>

The patch looks good to me. You can add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza


> ---
>  fs/ext4/file.c | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index 69d65d49837b..4b2ccaf1932e 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -360,15 +360,16 @@ static const struct vm_operations_struct ext4_file_vm_ops = {
>  static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
>  {
>  	struct inode *inode = file->f_mapping->host;
> +	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
> +	struct dax_device *dax_dev = sbi->s_daxdev;
>  
> -	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
> +	if (unlikely(ext4_forced_shutdown(sbi)))
>  		return -EIO;
>  
> -	/*
> -	 * We don't support synchronous mappings for non-DAX files. At least
> -	 * until someone comes with a sensible use case.
> +	/* We don't support synchronous mappings for non-DAX files and
> +	 * for DAX files if underneath dax_device is not synchronous.
>  	 */
> -	if (!IS_DAX(file_inode(file)) && (vma->vm_flags & VM_SYNC))
> +	if (!daxdev_mapping_supported(vma, dax_dev))
>  		return -EOPNOTSUPP;
>  
>  	file_accessed(file);
> -- 
> 2.20.1
>
Pankaj Gupta April 24, 2019, 5:21 a.m. UTC | #2
> 
> On Tue 23-04-19 13:36:11, Pankaj Gupta wrote:
> > Dont support 'MAP_SYNC' with non-DAX files and DAX files
> > with asynchronous dax_device. Virtio pmem provides
> > asynchronous host page cache flush mechanism. We don't
> > support 'MAP_SYNC' with virtio pmem and ext4.
> > 
> > Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
> 
> The patch looks good to me. You can add:
> 
> Reviewed-by: Jan Kara <jack@suse.cz>

Thank you. Will add this.

Best regards,
Pankaj

> 
> 								Honza
> 
> 
> > ---
> >  fs/ext4/file.c | 11 ++++++-----
> >  1 file changed, 6 insertions(+), 5 deletions(-)
> > 
> > diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> > index 69d65d49837b..4b2ccaf1932e 100644
> > --- a/fs/ext4/file.c
> > +++ b/fs/ext4/file.c
> > @@ -360,15 +360,16 @@ static const struct vm_operations_struct
> > ext4_file_vm_ops = {
> >  static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
> >  {
> >  	struct inode *inode = file->f_mapping->host;
> > +	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
> > +	struct dax_device *dax_dev = sbi->s_daxdev;
> >  
> > -	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
> > +	if (unlikely(ext4_forced_shutdown(sbi)))
> >  		return -EIO;
> >  
> > -	/*
> > -	 * We don't support synchronous mappings for non-DAX files. At least
> > -	 * until someone comes with a sensible use case.
> > +	/* We don't support synchronous mappings for non-DAX files and
> > +	 * for DAX files if underneath dax_device is not synchronous.
> >  	 */
> > -	if (!IS_DAX(file_inode(file)) && (vma->vm_flags & VM_SYNC))
> > +	if (!daxdev_mapping_supported(vma, dax_dev))
> >  		return -EOPNOTSUPP;
> >  
> >  	file_accessed(file);
> > --
> > 2.20.1
> > 
> --
> Jan Kara <jack@suse.com>
> SUSE Labs, CR
> 
>

Patch
diff mbox series

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 69d65d49837b..4b2ccaf1932e 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -360,15 +360,16 @@  static const struct vm_operations_struct ext4_file_vm_ops = {
 static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
 {
 	struct inode *inode = file->f_mapping->host;
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+	struct dax_device *dax_dev = sbi->s_daxdev;
 
-	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
+	if (unlikely(ext4_forced_shutdown(sbi)))
 		return -EIO;
 
-	/*
-	 * We don't support synchronous mappings for non-DAX files. At least
-	 * until someone comes with a sensible use case.
+	/* We don't support synchronous mappings for non-DAX files and
+	 * for DAX files if underneath dax_device is not synchronous.
 	 */
-	if (!IS_DAX(file_inode(file)) && (vma->vm_flags & VM_SYNC))
+	if (!daxdev_mapping_supported(vma, dax_dev))
 		return -EOPNOTSUPP;
 
 	file_accessed(file);