alistair23-linux/fs/dlm/lock.h
David Teigland 2ab4bd8ea3 dlm: adopt orphan locks
A process may exit, leaving an orphan lock in the lockspace.
This adds the capability for another process to acquire the
orphan lock.  Acquiring the orphan just moves the lock from
the orphan list onto the acquiring process's list of locks.

An adopting process must specify the resource name and mode
of the lock it wants to adopt.  If a matching lock is found,
the lock is moved to the caller's 's list of locks, and the
lkid of the lock is returned like the lkid of a new lock.

If an orphan with a different mode is found, then -EAGAIN is
returned.  If no orphan lock is found on the resource, then
-ENOENT is returned.  No async completion is used because
the result is immediately available.

Also, when orphans are purged, allow a zero nodeid to refer
to the local nodeid so the caller does not need to look up
the local nodeid.

Signed-off-by: David Teigland <teigland@redhat.com>
2014-11-19 14:48:02 -06:00

81 lines
3.1 KiB
C

/******************************************************************************
*******************************************************************************
**
** Copyright (C) 2005-2007 Red Hat, Inc. All rights reserved.
**
** This copyrighted material is made available to anyone wishing to use,
** modify, copy, or redistribute it subject to the terms and conditions
** of the GNU General Public License v.2.
**
*******************************************************************************
******************************************************************************/
#ifndef __LOCK_DOT_H__
#define __LOCK_DOT_H__
void dlm_dump_rsb(struct dlm_rsb *r);
void dlm_dump_rsb_name(struct dlm_ls *ls, char *name, int len);
void dlm_print_lkb(struct dlm_lkb *lkb);
void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms,
uint32_t saved_seq);
void dlm_receive_buffer(union dlm_packet *p, int nodeid);
int dlm_modes_compat(int mode1, int mode2);
void dlm_put_rsb(struct dlm_rsb *r);
void dlm_hold_rsb(struct dlm_rsb *r);
int dlm_put_lkb(struct dlm_lkb *lkb);
void dlm_scan_rsbs(struct dlm_ls *ls);
int dlm_lock_recovery_try(struct dlm_ls *ls);
void dlm_unlock_recovery(struct dlm_ls *ls);
void dlm_scan_waiters(struct dlm_ls *ls);
void dlm_scan_timeout(struct dlm_ls *ls);
void dlm_adjust_timeouts(struct dlm_ls *ls);
int dlm_master_lookup(struct dlm_ls *ls, int nodeid, char *name, int len,
unsigned int flags, int *r_nodeid, int *result);
int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
struct dlm_rsb **r_ret);
void dlm_recover_purge(struct dlm_ls *ls);
void dlm_purge_mstcpy_locks(struct dlm_rsb *r);
void dlm_recover_grant(struct dlm_ls *ls);
int dlm_recover_waiters_post(struct dlm_ls *ls);
void dlm_recover_waiters_pre(struct dlm_ls *ls);
int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc);
int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc);
int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua, int mode,
uint32_t flags, void *name, unsigned int namelen,
unsigned long timeout_cs);
int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
unsigned long timeout_cs);
int dlm_user_adopt_orphan(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
int mode, uint32_t flags, void *name, unsigned int namelen,
unsigned long timeout_cs, uint32_t *lkid);
int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
uint32_t flags, uint32_t lkid, char *lvb_in);
int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
uint32_t flags, uint32_t lkid);
int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
int nodeid, int pid);
int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid);
void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc);
static inline int is_master(struct dlm_rsb *r)
{
return !r->res_nodeid;
}
static inline void lock_rsb(struct dlm_rsb *r)
{
mutex_lock(&r->res_mutex);
}
static inline void unlock_rsb(struct dlm_rsb *r)
{
mutex_unlock(&r->res_mutex);
}
#endif