procfs: add ability to plug in auxiliary fdinfo providers

This patch brings ability to print out auxiliary data associated with
file in procfs interface /proc/pid/fdinfo/fd.

In particular further patches make eventfd, evenpoll, signalfd and
fsnotify to print additional information complete enough to restore
these objects after checkpoint.

To simplify the code we add show_fdinfo callback inside struct
file_operations (as Al and Pavel are proposing).

Signed-off-by: Cyrill Gorcunov <[email protected]>
Acked-by: Pavel Emelyanov <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andrey Vagin <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: James Bottomley <[email protected]>
Cc: "Aneesh Kumar K.V" <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Matthew Helsley <[email protected]>
Cc: "J. Bruce Fields" <[email protected]>
Cc: "Aneesh Kumar K.V" <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions