Re: [PATCH v3 06/13] ceph: move fscrypt to filesystem inode

[Eric Biggers <ebiggers@kernel.org>]

On Tue, Jul 22, 2025 at 09:27:24PM +0200, Christian Brauner wrote:
> Move fscrypt data pointer into the filesystem's private inode and record
> the offset from the embedded struct inode.
> 
> This will allow us to drop the fscrypt data pointer from struct inode
> itself and move it into the filesystem's inode.
> 
> Signed-off-by: Christian Brauner <brauner@kernel.org>
> ---
>  fs/ceph/super.c       | 4 ++++
>  include/linux/netfs.h | 6 ++++++
>  2 files changed, 10 insertions(+)
> 
> diff --git a/fs/ceph/super.c b/fs/ceph/super.c
> index 2b8438d8a324..540b32e746de 100644
> --- a/fs/ceph/super.c
> +++ b/fs/ceph/super.c
> @@ -1039,6 +1039,10 @@ void ceph_umount_begin(struct super_block *sb)
>  }
>  
>  static const struct super_operations ceph_super_ops = {
> +#ifdef CONFIG_FS_ENCRYPTION
> +	.i_fscrypt = offsetof(struct ceph_inode_info, netfs.i_fscrypt_info) -
> +		     offsetof(struct ceph_inode_info, netfs.inode),
> +#endif
>  	.alloc_inode	= ceph_alloc_inode,
>  	.free_inode	= ceph_free_inode,
>  	.write_inode    = ceph_write_inode,
> diff --git a/include/linux/netfs.h b/include/linux/netfs.h
> index 065c17385e53..fda1321da861 100644
> --- a/include/linux/netfs.h
> +++ b/include/linux/netfs.h
> @@ -57,6 +57,9 @@ typedef void (*netfs_io_terminated_t)(void *priv, ssize_t transferred_or_error);
>   */
>  struct netfs_inode {
>  	struct inode		inode;		/* The VFS inode */
> +#ifdef CONFIG_FS_ENCRYPTION
> +	struct fscrypt_inode_info *i_fscrypt_info;
> +#endif
>  	const struct netfs_request_ops *ops;
>  #if IS_ENABLED(CONFIG_FSCACHE)
>  	struct fscache_cookie	*cache;
> @@ -503,6 +506,9 @@ static inline void netfs_inode_init(struct netfs_inode *ctx,
>  		ctx->zero_point = ctx->remote_i_size;
>  		mapping_set_release_always(ctx->inode.i_mapping);
>  	}
> +#ifdef CONFIG_FS_ENCRYPTION
> +	ctx->i_fscrypt_info = NULL;
> +#endif

Why netfs_inode instead of ceph_inode_info?

- Eric