On Wed 26-05-21 12:11:43, Damien Le Moal wrote: > On 2021/05/26 19:07, Jan Kara wrote: > > On Tue 25-05-21 13:48:05, Darrick J. Wong wrote: > >> On Tue, May 25, 2021 at 03:50:41PM +0200, Jan Kara wrote: > >>> Some operations such as reflinking blocks among files will need to lock > >>> invalidate_lock for two mappings. Add helper functions to do that. > >>> > >>> Signed-off-by: Jan Kara <jack@xxxxxxx> > >>> --- > >>> include/linux/fs.h | 6 ++++++ > >>> mm/filemap.c | 38 ++++++++++++++++++++++++++++++++++++++ > >>> 2 files changed, 44 insertions(+) > >>> > >>> diff --git a/include/linux/fs.h b/include/linux/fs.h > >>> index 897238d9f1e0..e6f7447505f5 100644 > >>> --- a/include/linux/fs.h > >>> +++ b/include/linux/fs.h > >>> @@ -822,6 +822,12 @@ static inline void inode_lock_shared_nested(struct inode *inode, unsigned subcla > >>> void lock_two_nondirectories(struct inode *, struct inode*); > >>> void unlock_two_nondirectories(struct inode *, struct inode*); > >>> > >>> +void filemap_invalidate_down_write_two(struct address_space *mapping1, > >>> + struct address_space *mapping2); > >>> +void filemap_invalidate_up_write_two(struct address_space *mapping1, > >> > >> TBH I find myself wishing that the invalidate_lock used the same > >> lock/unlock style wrappers that we use for i_rwsem. > >> > >> filemap_invalidate_lock(inode1->mapping); > >> filemap_invalidate_lock_two(inode1->i_mapping, inode2->i_mapping); > > > > OK, and filemap_invalidate_lock_shared() for down_read()? I guess that > > works for me. > > What about filemap_invalidate_lock_read() and filemap_invalidate_lock_write() ? > That reminds the down_read()/down_write() without the slightly confusing down/up. Well, if we go for lock wrappers as Darrick suggested, I'd mirror naming used for inode_lock(). That is IMO the least confusing option... And that naming has _lock and _lock_shared suffixes. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
