On Mon, Apr 13, 2020 at 09:09:29AM -0700, Darrick J. Wong wrote:
> > Subject: [PATCH V7 7/9] fs: Define I_DONTCACNE in VFS layer
>
> CACNE -> CACHE.
>
> On Sun, Apr 12, 2020 at 10:40:44PM -0700, ira.weiny@xxxxxxxxx wrote:
> > From: Ira Weiny <ira.weiny@xxxxxxxxx>
> >
> > DAX effective mode changes (setting of S_DAX) require inode eviction.
> >
> > Define a flag which can be set to inform the VFS layer that inodes
> > should not be cached. This will expedite the eviction of those nodes
> > requiring reload.
> >
> > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> > ---
> > include/linux/fs.h | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/linux/fs.h b/include/linux/fs.h
> > index a818ced22961..e2db71d150c3 100644
> > --- a/include/linux/fs.h
> > +++ b/include/linux/fs.h
> > @@ -2151,6 +2151,8 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
> > *
> > * I_CREATING New object's inode in the middle of setting up.
> > *
> > + * I_DONTCACHE Do not cache the inode
>
> "Do not cache" is a bit vague, how about:
>
> "Evict the inode when the last reference is dropped.
> Do not put it on the LRU list."
>
> Also, shouldn't xfs_ioctl_setattr be setting I_DONTCACHE if someone
> changes FS_XFLAG_DAX (and there are no mount option overrides)? I don't
> see any user of I_DONTCACHE in this series.
Oops, brain fart, ignore this question ^^^^.
--D
> (Also also, please convert XFS_IDONTCACHE, since it's a straightforward
> conversion...)
>
> --D
>
> > + *
> > * Q: What is the difference between I_WILL_FREE and I_FREEING?
> > */
> > #define I_DIRTY_SYNC (1 << 0)
> > @@ -2173,6 +2175,7 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
> > #define I_WB_SWITCH (1 << 13)
> > #define I_OVL_INUSE (1 << 14)
> > #define I_CREATING (1 << 15)
> > +#define I_DONTCACHE (1 << 16)
> >
> > #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
> > #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
> > @@ -3042,7 +3045,8 @@ extern int inode_needs_sync(struct inode *inode);
> > extern int generic_delete_inode(struct inode *inode);
> > static inline int generic_drop_inode(struct inode *inode)
> > {
> > - return !inode->i_nlink || inode_unhashed(inode);
> > + return !inode->i_nlink || inode_unhashed(inode) ||
> > + (inode->i_state & I_DONTCACHE);
> > }
> >
> > extern struct inode *ilookup5_nowait(struct super_block *sb,
> > --
> > 2.25.1
> >
