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

[Joseph Qi <joseph.qi@linux.alibaba.com>]

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@kernel.org>
> ---
>  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@linux.alibaba.com>

>  	/*
>  	 * 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

>   * @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);

...