diff mbox series

[V1,2/9] fs/ext4: Disallow verity if inode is DAX

Message ID 20200514065316.2500078-3-ira.weiny@intel.com
State New
Headers show
Series Enable ext4 support for per-file/directory DAX operations | expand

Commit Message

Ira Weiny May 14, 2020, 6:53 a.m. UTC
From: Ira Weiny <ira.weiny@intel.com>

Verity and DAX are incompatible.  Changing the DAX mode due to a verity
flag change is wrong without a corresponding address_space_operations
update.

Make the 2 options mutually exclusive by returning an error if DAX was
set first.

(Setting DAX is already disabled if Verity is set first.)

Signed-off-by: Ira Weiny <ira.weiny@intel.com>

---
Changes:
	remove WARN_ON_ONCE
	Add documentation for DAX/Verity exclusivity
---
 Documentation/filesystems/ext4/verity.rst | 7 +++++++
 fs/ext4/verity.c                          | 3 +++
 2 files changed, 10 insertions(+)

Comments

Jan Kara May 14, 2020, 10:21 a.m. UTC | #1
On Wed 13-05-20 23:53:08, ira.weiny@intel.com wrote:
> From: Ira Weiny <ira.weiny@intel.com>
> 
> Verity and DAX are incompatible.  Changing the DAX mode due to a verity
> flag change is wrong without a corresponding address_space_operations
> update.
> 
> Make the 2 options mutually exclusive by returning an error if DAX was
> set first.
> 
> (Setting DAX is already disabled if Verity is set first.)
> 
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>

Makes sence. You can add:

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

								Honza


> 
> ---
> Changes:
> 	remove WARN_ON_ONCE
> 	Add documentation for DAX/Verity exclusivity
> ---
>  Documentation/filesystems/ext4/verity.rst | 7 +++++++
>  fs/ext4/verity.c                          | 3 +++
>  2 files changed, 10 insertions(+)
> 
> diff --git a/Documentation/filesystems/ext4/verity.rst b/Documentation/filesystems/ext4/verity.rst
> index 3e4c0ee0e068..51ab1aa17e59 100644
> --- a/Documentation/filesystems/ext4/verity.rst
> +++ b/Documentation/filesystems/ext4/verity.rst
> @@ -39,3 +39,10 @@ is encrypted as well as the data itself.
>  
>  Verity files cannot have blocks allocated past the end of the verity
>  metadata.
> +
> +Verity and DAX
> +--------------
> +
> +Verity and DAX are not compatible and attempts to set both of these flags on a
> +file will fail.
> +
> diff --git a/fs/ext4/verity.c b/fs/ext4/verity.c
> index dc5ec724d889..f05a09fb2ae4 100644
> --- a/fs/ext4/verity.c
> +++ b/fs/ext4/verity.c
> @@ -113,6 +113,9 @@ static int ext4_begin_enable_verity(struct file *filp)
>  	handle_t *handle;
>  	int err;
>  
> +	if (IS_DAX(inode))
> +		return -EINVAL;
> +
>  	if (ext4_verity_in_progress(inode))
>  		return -EBUSY;
>  
> -- 
> 2.25.1
>
diff mbox series

Patch

diff --git a/Documentation/filesystems/ext4/verity.rst b/Documentation/filesystems/ext4/verity.rst
index 3e4c0ee0e068..51ab1aa17e59 100644
--- a/Documentation/filesystems/ext4/verity.rst
+++ b/Documentation/filesystems/ext4/verity.rst
@@ -39,3 +39,10 @@  is encrypted as well as the data itself.
 
 Verity files cannot have blocks allocated past the end of the verity
 metadata.
+
+Verity and DAX
+--------------
+
+Verity and DAX are not compatible and attempts to set both of these flags on a
+file will fail.
+
diff --git a/fs/ext4/verity.c b/fs/ext4/verity.c
index dc5ec724d889..f05a09fb2ae4 100644
--- a/fs/ext4/verity.c
+++ b/fs/ext4/verity.c
@@ -113,6 +113,9 @@  static int ext4_begin_enable_verity(struct file *filp)
 	handle_t *handle;
 	int err;
 
+	if (IS_DAX(inode))
+		return -EINVAL;
+
 	if (ext4_verity_in_progress(inode))
 		return -EBUSY;