On Mon, 2018-03-19 at 10:36 -0400, J. Bruce Fields wrote:
> From: "J. Bruce Fields" <bfields@xxxxxxxxxx>
>
> This is my second attempt to fix the NFS server so we don't
> unnecessarily recall delegations when the operation breaking the
> delegation comes from the same client that holds the delegation.
>
> To do that we need some way to pass the identity of the breaker down
> through the VFS. In my first attempt I tried passing that explicitly,
> but that touches a lot of code. So instead I'm experimenting with
> adding a field to the cred struct.
>
> Testing has confirmed that this works. (And that the pynfs tests are
> broken--they *require* the server to break delegations on operations
> coming from the client, even though that's the less desireable behavior.
> I'm fixing that...).
>
> J. Bruce Fields (10):
> vfs: remove unnecessary fl_owner_t typedef
> nfsd: simplify put of fi_deleg_file
> nfsd: simplify nfs4_put_deleg_lease calls
> nfsd4: set fl_owner to delegation, not file pointer
> nfsd4: dp->dl_stid.sc_file doesn't need locking
> nfsd: make nfs4_get_existing_delegation less confusing
> nfsd: factor out common delegation-destruction code
> nfsd: move sc_file assignment into alloc_init_deleg
> nfsd: create a separate lease for each delegation
> nfsd: clients don't need to break their own delegations
>
> Documentation/filesystems/Locking | 2 +
> Documentation/filesystems/vfs.txt | 2 +-
> arch/ia64/kernel/perfmon.c | 2 +-
> arch/powerpc/platforms/cell/spufs/file.c | 2 +-
> arch/tile/kernel/hardwall.c | 2 +-
> drivers/android/binder.c | 2 +-
> drivers/char/ps3flash.c | 2 +-
> drivers/char/xillybus/xillybus_core.c | 2 +-
> drivers/firmware/efi/capsule-loader.c | 2 +-
> drivers/input/evdev.c | 2 +-
> drivers/misc/mic/scif/scif_fd.c | 2 +-
> drivers/scsi/osst.c | 2 +-
> drivers/scsi/st.c | 2 +-
> drivers/staging/lustre/lustre/llite/file.c | 2 +-
> drivers/usb/class/cdc-wdm.c | 2 +-
> drivers/usb/usb-skeleton.c | 2 +-
> fs/afs/internal.h | 2 +-
> fs/afs/write.c | 2 +-
> fs/cifs/cifsfs.h | 2 +-
> fs/cifs/file.c | 4 +-
> fs/ecryptfs/file.c | 2 +-
> fs/exofs/file.c | 2 +-
> fs/f2fs/file.c | 2 +-
> fs/fuse/file.c | 13 +-
> fs/fuse/fuse_i.h | 2 +-
> fs/lockd/clntproc.c | 4 +-
> fs/lockd/svc4proc.c | 2 +-
> fs/lockd/svcproc.c | 2 +-
> fs/locks.c | 6 +-
> fs/nfs/file.c | 2 +-
> fs/nfs/inode.c | 2 +-
> fs/nfs/nfs4_fs.h | 2 +-
> fs/nfs/nfs4file.c | 2 +-
> fs/nfs/nfs4state.c | 8 +-
> fs/nfsd/auth.c | 2 +
> fs/nfsd/nfs4proc.c | 1 +
> fs/nfsd/nfs4state.c | 267 ++++++++++++-----------------
> fs/nfsd/nfssvc.c | 1 +
> fs/notify/dnotify/dnotify.c | 6 +-
> fs/open.c | 2 +-
> include/linux/cred.h | 3 +
> include/linux/dnotify.h | 6 +-
> include/linux/fs.h | 18 +-
> include/linux/lockd/lockd.h | 4 +-
> include/linux/nfs_fs.h | 4 +-
> include/linux/sunrpc/svc.h | 1 +
> include/trace/events/filelock.h | 6 +-
> ipc/mqueue.c | 2 +-
> 48 files changed, 193 insertions(+), 223 deletions(-)
>
Nice work.
The whole first part of the series looks like a nice set of cleanups
(sans the first patch, as there seems to be support to keep fl_owner_t
typedef around). Giving each delegation its own lease makes a lot more
sense, IMO.
On patches 2-9, you can add:
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
...and maybe get those into -next soon? The delegation code has been a
source of subtle bugs in the past, so we really want this to get a lot
of testing.
With patch 10, I have some concern about growing a common structure like
struct cred with such a special-purpose field.
An alternative might be to utilize the keyrings there -- maybe stash a
special sort of key on one of the keyrings with this pointer? We'd need
to take care to prevent userland from doing this, but that seems like a
solvable problem.
Cheers,
--
Jeff Layton <jlayton@xxxxxxxxxx>
