include/uapi/linux/dlm.h

   1 /******************************************************************************
   2 *******************************************************************************
   3 **
   4 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
   5 **  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
   6 **
   7 **  This copyrighted material is made available to anyone wishing to use,
   8 **  modify, copy, or redistribute it subject to the terms and conditions
   9 **  of the GNU General Public License v.2.
  10 **
  11 *******************************************************************************
  12 ******************************************************************************/
  13
  14 #ifndef _UAPI__DLM_DOT_H__
  15 #define _UAPI__DLM_DOT_H__
  16
  17 /*
  18  * Interface to Distributed Lock Manager (DLM)
  19  * routines and structures to use DLM lockspaces
  20  */
  21
  22 /* Lock levels and flags are here */
  23 #include <linux/dlmconstants.h>
  24 #include <linux/types.h>
  25
  26 typedef void dlm_lockspace_t;
  27
  28 /*
  29  * Lock status block
  30  *
  31  * Use this structure to specify the contents of the lock value block.  For a
  32  * conversion request, this structure is used to specify the lock ID of the
  33  * lock.  DLM writes the status of the lock request and the lock ID assigned
  34  * to the request in the lock status block.
  35  *
  36  * sb_lkid: the returned lock ID.  It is set on new (non-conversion) requests.
  37  * It is available when dlm_lock returns.
  38  *
  39  * sb_lvbptr: saves or returns the contents of the lock's LVB according to rules
  40  * shown for the DLM_LKF_VALBLK flag.
  41  *
  42  * sb_flags: DLM_SBF_DEMOTED is returned if in the process of promoting a lock,
  43  * it was first demoted to NL to avoid conversion deadlock.
  44  * DLM_SBF_VALNOTVALID is returned if the resource's LVB is marked invalid.
  45  *
  46  * sb_status: the returned status of the lock request set prior to AST
  47  * execution.  Possible return values:
  48  *
  49  * 0 if lock request was successful
  50  * -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE
  51  * -DLM_EUNLOCK if unlock request was successful
  52  * -DLM_ECANCEL if a cancel completed successfully
  53  * -EDEADLK if a deadlock was detected
  54  * -ETIMEDOUT if the lock request was canceled due to a timeout
  55  */
  56
  57 #define DLM_SBF_DEMOTED         0x01
  58 #define DLM_SBF_VALNOTVALID     0x02
  59 #define DLM_SBF_ALTMODE         0x04
  60
  61 struct dlm_lksb {
  62         int      sb_status;
  63         __u32    sb_lkid;
  64         char     sb_flags;
  65         char *   sb_lvbptr;
  66 };
  67
  68 /* dlm_new_lockspace() flags */
  69
  70 #define DLM_LSFL_TIMEWARN       0x00000002
  71 #define DLM_LSFL_FS             0x00000004
  72 #define DLM_LSFL_NEWEXCL        0x00000008
  73
  74
  75 #endif /* _UAPI__DLM_DOT_H__ */