linux/fs/ocfs2/dlm/dlmconvert.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * dlmconvert.c
 *
 * underlying calls for lock conversion
 *
 * Copyright (C) 2004 Oracle.  All rights reserved.
 */


#include <linux/module.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/highmem.h>
#include <linux/init.h>
#include <linux/sysctl.h>
#include <linux/random.h>
#include <linux/blkdev.h>
#include <linux/socket.h>
#include <linux/inet.h>
#include <linux/spinlock.h>


#include "../cluster/heartbeat.h"
#include "../cluster/nodemanager.h"
#include "../cluster/tcp.h"

#include "dlmapi.h"
#include "dlmcommon.h"

#include "dlmconvert.h"

#define MLOG_MASK_PREFIX …
#include "../cluster/masklog.h"

/* NOTE: __dlmconvert_master is the only function in here that
 * needs a spinlock held on entry (res->spinlock) and it is the
 * only one that holds a lock on exit (res->spinlock).
 * All other functions in here need no locks and drop all of
 * the locks that they acquire. */
static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
					   struct dlm_lock_resource *res,
					   struct dlm_lock *lock, int flags,
					   int type, int *call_ast,
					   int *kick_thread);
static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
					   struct dlm_lock_resource *res,
					   struct dlm_lock *lock, int flags, int type);

/*
 * this is only called directly by dlmlock(), and only when the
 * local node is the owner of the lockres
 * locking:
 *   caller needs:  none
 *   taken:         takes and drops res->spinlock
 *   held on exit:  none
 * returns: see __dlmconvert_master
 */
enum dlm_status dlmconvert_master(struct dlm_ctxt *dlm,
				  struct dlm_lock_resource *res,
				  struct dlm_lock *lock, int flags, int type)
{ … }

/* performs lock conversion at the lockres master site
 * locking:
 *   caller needs:  res->spinlock
 *   taken:         takes and drops lock->spinlock
 *   held on exit:  res->spinlock
 * returns: DLM_NORMAL, DLM_NOTQUEUED, DLM_DENIED
 *   call_ast: whether ast should be called for this lock
 *   kick_thread: whether dlm_kick_thread should be called
 */
static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
					   struct dlm_lock_resource *res,
					   struct dlm_lock *lock, int flags,
					   int type, int *call_ast,
					   int *kick_thread)
{ … }

void dlm_revert_pending_convert(struct dlm_lock_resource *res,
				struct dlm_lock *lock)
{ … }

/* messages the master site to do lock conversion
 * locking:
 *   caller needs:  none
 *   taken:         takes and drops res->spinlock, uses DLM_LOCK_RES_IN_PROGRESS
 *   held on exit:  none
 * returns: DLM_NORMAL, DLM_RECOVERING, status from remote node
 */
enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
				  struct dlm_lock_resource *res,
				  struct dlm_lock *lock, int flags, int type)
{ … }

/* sends DLM_CONVERT_LOCK_MSG to master site
 * locking:
 *   caller needs:  none
 *   taken:         none
 *   held on exit:  none
 * returns: DLM_NOLOCKMGR, status from remote node
 */
static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
					   struct dlm_lock_resource *res,
					   struct dlm_lock *lock, int flags, int type)
{ … }

/* handler for DLM_CONVERT_LOCK_MSG on master site
 * locking:
 *   caller needs:  none
 *   taken:         takes and drop res->spinlock
 *   held on exit:  none
 * returns: DLM_NORMAL, DLM_IVLOCKID, DLM_BADARGS,
 *          status from __dlmconvert_master
 */
int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
			     void **ret_data)
{ … }