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

Christian Brauner
2025-07-23T08:58:53Z

On Tue, Jul 22, 2025 at 01:14:06PM -0700, Eric Biggers wrote:
> 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?

If we add asserts that struct inode must be located at the beginning of
struct netfs_inode then I would feel comfortable doing that. I'll do
that.