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

[Al Viro]

On Tue, Jul 25, 2023 at 10:58:14AM -0400, 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.

Out of curiosity - how much PITA would it be to put request_mask into
kstat?  Set it in vfs_getattr_nosec() (and those get_file_..._info()
on smbd side) and don't bother with that kind of propagation boilerplate
- just have generic_fillattr() pick it there...

Reduces the patchset size quite a bit...