Re: [PATCH v6 1/7] fs: pass the request_mask to generic_fillattr

[Jeff Layton]

On Wed, 2023-07-26 at 17:40 +0800, Joseph Qi wrote:
> 
> On 7/25/23 10:58 PM, Jeff Layton wrote:
> > generic_fillattr just fills in the entire stat struct indiscriminately
> > today, copying data from the inode. There is at least one attribute
> > (STATX_CHANGE_COOKIE) that can have side effects when it is reported,
> > and we're looking at adding more with the addition of multigrain
> > timestamps.
> > 
> > Add a request_mask argument to generic_fillattr and have most callers
> > just pass in the value that is passed to getattr. Have other callers
> > (e.g. ksmbd) just pass in STATX_BASIC_STATS. Also move the setting of
> > STATX_CHANGE_COOKIE into generic_fillattr.
> > 
> > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> > ---
> >  fs/9p/vfs_inode.c       |  4 ++--
> >  fs/9p/vfs_inode_dotl.c  |  4 ++--
> >  fs/afs/inode.c          |  2 +-
> >  fs/btrfs/inode.c        |  2 +-
> >  fs/ceph/inode.c         |  2 +-
> >  fs/coda/inode.c         |  3 ++-
> >  fs/ecryptfs/inode.c     |  5 +++--
> >  fs/erofs/inode.c        |  2 +-
> >  fs/exfat/file.c         |  2 +-
> >  fs/ext2/inode.c         |  2 +-
> >  fs/ext4/inode.c         |  2 +-
> >  fs/f2fs/file.c          |  2 +-
> >  fs/fat/file.c           |  2 +-
> >  fs/fuse/dir.c           |  2 +-
> >  fs/gfs2/inode.c         |  2 +-
> >  fs/hfsplus/inode.c      |  2 +-
> >  fs/kernfs/inode.c       |  2 +-
> >  fs/libfs.c              |  4 ++--
> >  fs/minix/inode.c        |  2 +-
> >  fs/nfs/inode.c          |  2 +-
> >  fs/nfs/namespace.c      |  3 ++-
> >  fs/ntfs3/file.c         |  2 +-
> >  fs/ocfs2/file.c         |  2 +-
> >  fs/orangefs/inode.c     |  2 +-
> >  fs/proc/base.c          |  4 ++--
> >  fs/proc/fd.c            |  2 +-
> >  fs/proc/generic.c       |  2 +-
> >  fs/proc/proc_net.c      |  2 +-
> >  fs/proc/proc_sysctl.c   |  2 +-
> >  fs/proc/root.c          |  3 ++-
> >  fs/smb/client/inode.c   |  2 +-
> >  fs/smb/server/smb2pdu.c | 22 +++++++++++-----------
> >  fs/smb/server/vfs.c     |  3 ++-
> >  fs/stat.c               | 18 ++++++++++--------
> >  fs/sysv/itree.c         |  3 ++-
> >  fs/ubifs/dir.c          |  2 +-
> >  fs/udf/symlink.c        |  2 +-
> >  fs/vboxsf/utils.c       |  2 +-
> >  include/linux/fs.h      |  2 +-
> >  mm/shmem.c              |  2 +-
> >  40 files changed, 70 insertions(+), 62 deletions(-)
> > 
> 
> ...
> 
> > diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> > index 1b337ebce4df..8184499ae7a5 100644
> > --- a/fs/ocfs2/file.c
> > +++ b/fs/ocfs2/file.c
> > @@ -1319,7 +1319,7 @@ int ocfs2_getattr(struct mnt_idmap *idmap, const struct path *path,
> >  		goto bail;
> >  	}
> >  
> > -	generic_fillattr(&nop_mnt_idmap, inode, stat);
> > +	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
> 
> For ocfs2 part, looks fine to me.
> 
> Acked-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>
> 
> >  	/*
> >  	 * If there is inline data in the inode, the inode will normally not
> >  	 * have data blocks allocated (it may have an external xattr block).
> 
> ...
> 
> > diff --git a/fs/stat.c b/fs/stat.c
> > index 8c2b30af19f5..062f311b5386 100644
> > --- a/fs/stat.c
> > +++ b/fs/stat.c
> > @@ -29,6 +29,7 @@
> >  /**
> >   * generic_fillattr - Fill in the basic attributes from the inode struct
> >   * @idmap:	idmap of the mount the inode was found from
> > + * @req_mask	statx request_mask
> 
> s/req_mask/request_mask
> 

Thanks. Fixed in my tree.

> >   * @inode:	Inode to use as the source
> >   * @stat:	Where to fill in the attributes
> >   *
> > @@ -42,8 +43,8 @@
> >   * uid and gid filds. On non-idmapped mounts or if permission checking is to be
> >   * performed on the raw inode simply passs @nop_mnt_idmap.
> >   */
> > -void generic_fillattr(struct mnt_idmap *idmap, struct inode *inode,
> > -		      struct kstat *stat)
> > +void generic_fillattr(struct mnt_idmap *idmap, u32 request_mask,
> > +		      struct inode *inode, struct kstat *stat)
> >  {
> >  	vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode);
> >  	vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode);
> > @@ -61,6 +62,12 @@ void generic_fillattr(struct mnt_idmap *idmap, struct inode *inode,
> >  	stat->ctime = inode_get_ctime(inode);
> >  	stat->blksize = i_blocksize(inode);
> >  	stat->blocks = inode->i_blocks;
> > +
> > +	if ((request_mask & STATX_CHANGE_COOKIE) && IS_I_VERSION(inode)) {
> > +		stat->result_mask |= STATX_CHANGE_COOKIE;
> > +		stat->change_cookie = inode_query_iversion(inode);
> > +	}
> > +
> >  }
> >  EXPORT_SYMBOL(generic_fillattr);
> >  
> > @@ -123,17 +130,12 @@ int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
> >  	stat->attributes_mask |= (STATX_ATTR_AUTOMOUNT |
> >  				  STATX_ATTR_DAX);
> >  
> > -	if ((request_mask & STATX_CHANGE_COOKIE) && IS_I_VERSION(inode)) {
> > -		stat->result_mask |= STATX_CHANGE_COOKIE;
> > -		stat->change_cookie = inode_query_iversion(inode);
> > -	}
> > -
> >  	idmap = mnt_idmap(path->mnt);
> >  	if (inode->i_op->getattr)
> >  		return inode->i_op->getattr(idmap, path, stat,
> >  					    request_mask, query_flags);
> >  
> > -	generic_fillattr(idmap, inode, stat);
> > +	generic_fillattr(idmap, request_mask, inode, stat);
> >  	return 0;
> >  }
> >  EXPORT_SYMBOL(vfs_getattr_nosec);
> 
> ...
> 

-- 
Jeff Layton <jlayton@xxxxxxxxxx>