On Tue, Nov 17, 2020 at 07:27:03AM -0500, Jeff Layton wrote:
> On Mon, 2020-11-16 at 22:18 -0500, J. Bruce Fields wrote:
> > From: "J. Bruce Fields" <bfields@xxxxxxxxxx>
> >
> > The i_version on NFS has pretty much opaque to the client, so we don't
> > want to give the low bit any special interpretation.
> >
> > Define a new FS_PRIVATE_I_VERSION flag for filesystems that manage the
> > i_version on their own.
> >
>
> Description here doesn't quite match the patch...
Oops, thanks.--b.
>
> > Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx>
> > ---
> > fs/nfs/export.c | 1 +
> > include/linux/exportfs.h | 1 +
> > include/linux/iversion.h | 4 ++++
> > 3 files changed, 6 insertions(+)
> >
> > diff --git a/fs/nfs/export.c b/fs/nfs/export.c
> > index 3430d6891e89..c2eb915a54ca 100644
> > --- a/fs/nfs/export.c
> > +++ b/fs/nfs/export.c
> > @@ -171,4 +171,5 @@ const struct export_operations nfs_export_ops = {
> > .encode_fh = nfs_encode_fh,
> > .fh_to_dentry = nfs_fh_to_dentry,
> > .get_parent = nfs_get_parent,
> > + .fetch_iversion = inode_peek_iversion_raw,
> > };
> > diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h
> > index 3ceb72b67a7a..6000121a201f 100644
> > --- a/include/linux/exportfs.h
> > +++ b/include/linux/exportfs.h
> > @@ -213,6 +213,7 @@ struct export_operations {
> > bool write, u32 *device_generation);
> > int (*commit_blocks)(struct inode *inode, struct iomap *iomaps,
> > int nr_iomaps, struct iattr *iattr);
> > + u64 (*fetch_iversion)(const struct inode *);
> > };
> >
> >
> >
> >
> >
> >
> >
> >
> > extern int exportfs_encode_inode_fh(struct inode *inode, struct fid *fid,
> > diff --git a/include/linux/iversion.h b/include/linux/iversion.h
> > index 2917ef990d43..481b3debf6bb 100644
> > --- a/include/linux/iversion.h
> > +++ b/include/linux/iversion.h
> > @@ -3,6 +3,7 @@
> > #define _LINUX_IVERSION_H
> >
> >
> >
> >
> >
> >
> >
> >
> > #include <linux/fs.h>
> > +#include <linux/exportfs.h>
> >
> >
> >
> >
> >
> >
> >
> >
> > /*
> > * The inode->i_version field:
> > @@ -306,6 +307,9 @@ inode_query_iversion(struct inode *inode)
> > {
> > u64 cur, old, new;
> >
> >
> >
> >
> >
> >
> >
> >
> > + if (inode->i_sb->s_export_op->fetch_iversion)
> > + return inode->i_sb->s_export_op->fetch_iversion(inode);
> > +
>
> This looks dangerous -- s_export_op could be a NULL pointer.
>
> > cur = inode_peek_iversion_raw(inode);
> > for (;;) {
> > /* If flag is already set, then no need to swap */
>
> --
> Jeff Layton <jlayton@xxxxxxxxxx>
