ksmbd: add SMB3 request replay support

SMB3 clients can replay selected requests after a channel disconnect by
setting SMB2_FLAGS_REPLAY_OPERATION. The command sequence window rejects
duplicate MessageIds on one connection, but it does not validate requests
resent on another channel with a new MessageId.

Add the state and validation required to replay durable CREATE and
file-handle operations:

- track each open ChannelSequence, outstanding request counts, and lock
  sequence entries.
- retain a request-owned open reference until the common response path
  completes ChannelSequence accounting.
- replay DurableHandleReqV2 CREATE requests by CreateGuid, validating the
  durable state, SecurityContext, session, lease key, and persistent flag.
- publish CreateGuid and SecurityContext before an oplock or lease break
  can defer CREATE, rejecting replays of that pending CREATE with
  STATUS_FILE_NOT_AVAILABLE.
- retain the original CREATE action and replay completed CreateGuid
  requests, including requests that did not receive a durable-handle grant,
  without modifying the existing open.
- make replayed oplock and lease break acknowledgements idempotent. And
- preserve SMB2_FLAGS_REPLAY_OPERATION in responses.

Return STATUS_FILE_NOT_AVAILABLE when ChannelSequence validation rejects a
replayed WRITE, IOCTL, or SET_INFO request.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

0 files changed, 0 insertions, 0 deletions