[deliverable/linux.git] / fs / ocfs2 / dlm / dlmconvert.c

/* -*- mode: c; c-basic-offset: 8; -*-
 * vim: noexpandtab sw=8 ts=8 sts=0:
 *
 * dlmconvert.c
 *
 * underlying calls for lock conversion
 *
 * Copyright (C) 2004 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 *
 */


#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 ML_DLM
#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)
{
	int call_ast = 0, kick_thread = 0;
	enum dlm_status status;

	spin_lock(&res->spinlock);
	/* we are not in a network handler, this is fine */
	__dlm_wait_on_lockres(res);
	__dlm_lockres_reserve_ast(res);
	res->state |= DLM_LOCK_RES_IN_PROGRESS;

	status = __dlmconvert_master(dlm, res, lock, flags, type,
				     &call_ast, &kick_thread);

	res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
	spin_unlock(&res->spinlock);
	wake_up(&res->wq);
	if (status != DLM_NORMAL && status != DLM_NOTQUEUED)
		dlm_error(status);

	/* either queue the ast or release it */
	if (call_ast)
		dlm_queue_ast(dlm, lock);
	else
		dlm_lockres_release_ast(dlm, res);

	if (kick_thread)
		dlm_kick_thread(dlm, res);

	return status;
}

/* 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)
{
	enum dlm_status status = DLM_NORMAL;
	struct dlm_lock *tmplock=NULL;

	assert_spin_locked(&res->spinlock);

	mlog(0, "type=%d, convert_type=%d, new convert_type=%d\n",
	     lock->ml.type, lock->ml.convert_type, type);

	spin_lock(&lock->spinlock);

	/* already converting? */
	if (lock->ml.convert_type != LKM_IVMODE) {
		mlog(ML_ERROR, "attempted to convert a lock with a lock "
		     "conversion pending\n");
		status = DLM_DENIED;
		goto unlock_exit;
	}

	/* must be on grant queue to convert */
	if (!dlm_lock_on_list(&res->granted, lock)) {
		mlog(ML_ERROR, "attempted to convert a lock not on grant "
		     "queue\n");
		status = DLM_DENIED;
		goto unlock_exit;
	}

	if (flags & LKM_VALBLK) {
		switch (lock->ml.type) {
			case LKM_EXMODE:
				/* EX + LKM_VALBLK + convert == set lvb */
				mlog(0, "will set lvb: converting %s->%s\n",
				     dlm_lock_mode_name(lock->ml.type),
				     dlm_lock_mode_name(type));
				lock->lksb->flags |= DLM_LKSB_PUT_LVB;
				break;
			case LKM_PRMODE:
			case LKM_NLMODE:
				/* refetch if new level is not NL */
				if (type > LKM_NLMODE) {
					mlog(0, "will fetch new value into "
					     "lvb: converting %s->%s\n",
					     dlm_lock_mode_name(lock->ml.type),
					     dlm_lock_mode_name(type));
					lock->lksb->flags |= DLM_LKSB_GET_LVB;
				} else {
					mlog(0, "will NOT fetch new value "
					     "into lvb: converting %s->%s\n",
					     dlm_lock_mode_name(lock->ml.type),
					     dlm_lock_mode_name(type));
					flags &= ~(LKM_VALBLK);
				}
				break;
		}
	}


	/* in-place downconvert? */
	if (type <= lock->ml.type)
		goto grant;

	/* upconvert from here on */
	status = DLM_NORMAL;
	list_for_each_entry(tmplock, &res->granted, list) {
		if (tmplock == lock)
			continue;
		if (!dlm_lock_compatible(tmplock->ml.type, type))
			goto switch_queues;
	}

	list_for_each_entry(tmplock, &res->converting, list) {
		if (!dlm_lock_compatible(tmplock->ml.type, type))
			goto switch_queues;
		/* existing conversion requests take precedence */
		if (!dlm_lock_compatible(tmplock->ml.convert_type, type))
			goto switch_queues;
	}

	/* fall thru to grant */

grant:
	mlog(0, "res %.*s, granting %s lock\n", res->lockname.len,
	     res->lockname.name, dlm_lock_mode_name(type));
	/* immediately grant the new lock type */
	lock->lksb->status = DLM_NORMAL;
	if (lock->ml.node == dlm->node_num)
		mlog(0, "doing in-place convert for nonlocal lock\n");
	lock->ml.type = type;
	if (lock->lksb->flags & DLM_LKSB_PUT_LVB)
		memcpy(res->lvb, lock->lksb->lvb, DLM_LVB_LEN);

	/*
	 * Move the lock to the tail because it may be the only lock which has
	 * an invalid lvb.
	 */
	list_move_tail(&lock->list, &res->granted);

	status = DLM_NORMAL;
	*call_ast = 1;
	goto unlock_exit;

switch_queues:
	if (flags & LKM_NOQUEUE) {
		mlog(0, "failed to convert NOQUEUE lock %.*s from "
		     "%d to %d...\n", res->lockname.len, res->lockname.name,
		     lock->ml.type, type);
		status = DLM_NOTQUEUED;
		goto unlock_exit;
	}
	mlog(0, "res %.*s, queueing...\n", res->lockname.len,
	     res->lockname.name);

	lock->ml.convert_type = type;
	/* do not alter lock refcount.  switching lists. */
	list_move_tail(&lock->list, &res->converting);

unlock_exit:
	spin_unlock(&lock->spinlock);
	if (status == DLM_DENIED) {
		__dlm_print_one_lock_resource(res);
	}
	if (status == DLM_NORMAL)
		*kick_thread = 1;
	return status;
}

void dlm_revert_pending_convert(struct dlm_lock_resource *res,
				struct dlm_lock *lock)
{
	/* do not alter lock refcount.  switching lists. */
	list_move_tail(&lock->list, &res->granted);
	lock->ml.convert_type = LKM_IVMODE;
	lock->lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
}

/* 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)
{
	enum dlm_status status;

	mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type,
	     lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS);

	spin_lock(&res->spinlock);
	if (res->state & DLM_LOCK_RES_RECOVERING) {
		mlog(0, "bailing out early since res is RECOVERING "
		     "on secondary queue\n");
		/* __dlm_print_one_lock_resource(res); */
		status = DLM_RECOVERING;
		goto bail;
	}
	/* will exit this call with spinlock held */
	__dlm_wait_on_lockres(res);

	if (lock->ml.convert_type != LKM_IVMODE) {
		__dlm_print_one_lock_resource(res);
		mlog(ML_ERROR, "converting a remote lock that is already "
		     "converting! (cookie=%u:%llu, conv=%d)\n",
		     dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
		     dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
		     lock->ml.convert_type);
		status = DLM_DENIED;
		goto bail;
	}

	if (lock->ml.type == type && lock->ml.convert_type == LKM_IVMODE) {
		mlog(0, "last convert request returned DLM_RECOVERING, but "
		     "owner has already queued and sent ast to me. res %.*s, "
		     "(cookie=%u:%llu, type=%d, conv=%d)\n",
		     res->lockname.len, res->lockname.name,
		     dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
		     dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
		     lock->ml.type, lock->ml.convert_type);
		status = DLM_NORMAL;
		goto bail;
	}

	res->state |= DLM_LOCK_RES_IN_PROGRESS;
	/* move lock to local convert queue */
	/* do not alter lock refcount.  switching lists. */
	list_move_tail(&lock->list, &res->converting);
	lock->convert_pending = 1;
	lock->ml.convert_type = type;

	if (flags & LKM_VALBLK) {
		if (lock->ml.type == LKM_EXMODE) {
			flags |= LKM_PUT_LVB;
			lock->lksb->flags |= DLM_LKSB_PUT_LVB;
		} else {
			if (lock->ml.convert_type == LKM_NLMODE)
				flags &= ~LKM_VALBLK;
			else {
				flags |= LKM_GET_LVB;
				lock->lksb->flags |= DLM_LKSB_GET_LVB;
			}
		}
	}
	spin_unlock(&res->spinlock);

	/* no locks held here.
	 * need to wait for a reply as to whether it got queued or not. */
	status = dlm_send_remote_convert_request(dlm, res, lock, flags, type);

	spin_lock(&res->spinlock);
	res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
	/* if it failed, move it back to granted queue.
	 * if master returns DLM_NORMAL and then down before sending ast,
	 * it may have already been moved to granted queue, reset to
	 * DLM_RECOVERING and retry convert */
	if (status != DLM_NORMAL) {
		if (status != DLM_NOTQUEUED)
			dlm_error(status);
		dlm_revert_pending_convert(res, lock);
	} else if (!lock->convert_pending) {
		mlog(0, "%s: res %.*s, owner died and lock has been moved back "
				"to granted list, retry convert.\n",
				dlm->name, res->lockname.len, res->lockname.name);
		status = DLM_RECOVERING;
	}

	lock->convert_pending = 0;
bail:
	spin_unlock(&res->spinlock);

	/* TODO: should this be a wake_one? */
	/* wake up any IN_PROGRESS waiters */
	wake_up(&res->wq);

	return status;
}

/* 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)
{
	struct dlm_convert_lock convert;
	int tmpret;
	enum dlm_status ret;
	int status = 0;
	struct kvec vec[2];
	size_t veclen = 1;

	mlog(0, "%.*s\n", res->lockname.len, res->lockname.name);

	memset(&convert, 0, sizeof(struct dlm_convert_lock));
	convert.node_idx = dlm->node_num;
	convert.requested_type = type;
	convert.cookie = lock->ml.cookie;
	convert.namelen = res->lockname.len;
	convert.flags = cpu_to_be32(flags);
	memcpy(convert.name, res->lockname.name, convert.namelen);

	vec[0].iov_len = sizeof(struct dlm_convert_lock);
	vec[0].iov_base = &convert;

	if (flags & LKM_PUT_LVB) {
		/* extra data to send if we are updating lvb */
		vec[1].iov_len = DLM_LVB_LEN;
		vec[1].iov_base = lock->lksb->lvb;
		veclen++;
	}

	tmpret = o2net_send_message_vec(DLM_CONVERT_LOCK_MSG, dlm->key,
					vec, veclen, res->owner, &status);
	if (tmpret >= 0) {
		// successfully sent and received
		ret = status;  // this is already a dlm_status
		if (ret == DLM_RECOVERING) {
			mlog(0, "node %u returned DLM_RECOVERING from convert "
			     "message!\n", res->owner);
		} else if (ret == DLM_MIGRATING) {
			mlog(0, "node %u returned DLM_MIGRATING from convert "
			     "message!\n", res->owner);
		} else if (ret == DLM_FORWARD) {
			mlog(0, "node %u returned DLM_FORWARD from convert "
			     "message!\n", res->owner);
		} else if (ret != DLM_NORMAL && ret != DLM_NOTQUEUED)
			dlm_error(ret);
	} else {
		mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
		     "node %u\n", tmpret, DLM_CONVERT_LOCK_MSG, dlm->key,
		     res->owner);
		if (dlm_is_host_down(tmpret)) {
			/* instead of logging the same network error over
			 * and over, sleep here and wait for the heartbeat
			 * to notice the node is dead.  times out after 5s. */
			dlm_wait_for_node_death(dlm, res->owner,
						DLM_NODE_DEATH_WAIT_MAX);
			ret = DLM_RECOVERING;
			mlog(0, "node %u died so returning DLM_RECOVERING "
			     "from convert message!\n", res->owner);
		} else {
			ret = dlm_err_to_dlm_status(tmpret);
		}
	}

	return ret;
}

/* 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)
{
	struct dlm_ctxt *dlm = data;
	struct dlm_convert_lock *cnv = (struct dlm_convert_lock *)msg->buf;
	struct dlm_lock_resource *res = NULL;
	struct dlm_lock *lock = NULL;
	struct dlm_lock *tmp_lock;
	struct dlm_lockstatus *lksb;
	enum dlm_status status = DLM_NORMAL;
	u32 flags;
	int call_ast = 0, kick_thread = 0, ast_reserved = 0, wake = 0;

	if (!dlm_grab(dlm)) {
		dlm_error(DLM_REJECTED);
		return DLM_REJECTED;
	}

	mlog_bug_on_msg(!dlm_domain_fully_joined(dlm),
			"Domain %s not fully joined!\n", dlm->name);

	if (cnv->namelen > DLM_LOCKID_NAME_MAX) {
		status = DLM_IVBUFLEN;
		dlm_error(status);
		goto leave;
	}

	flags = be32_to_cpu(cnv->flags);

	if ((flags & (LKM_PUT_LVB|LKM_GET_LVB)) ==
	     (LKM_PUT_LVB|LKM_GET_LVB)) {
		mlog(ML_ERROR, "both PUT and GET lvb specified\n");
		status = DLM_BADARGS;
		goto leave;
	}

	mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" :
	     (flags & LKM_GET_LVB ? "get lvb" : "none"));

	status = DLM_IVLOCKID;
	res = dlm_lookup_lockres(dlm, cnv->name, cnv->namelen);
	if (!res) {
		dlm_error(status);
		goto leave;
	}

	spin_lock(&res->spinlock);
	status = __dlm_lockres_state_to_status(res);
	if (status != DLM_NORMAL) {
		spin_unlock(&res->spinlock);
		dlm_error(status);
		goto leave;
	}
	list_for_each_entry(tmp_lock, &res->granted, list) {
		if (tmp_lock->ml.cookie == cnv->cookie &&
		    tmp_lock->ml.node == cnv->node_idx) {
			lock = tmp_lock;
			dlm_lock_get(lock);
			break;
		}
	}
	spin_unlock(&res->spinlock);
	if (!lock) {
		status = DLM_IVLOCKID;
		mlog(ML_ERROR, "did not find lock to convert on grant queue! "
			       "cookie=%u:%llu\n",
		     dlm_get_lock_cookie_node(be64_to_cpu(cnv->cookie)),
		     dlm_get_lock_cookie_seq(be64_to_cpu(cnv->cookie)));
		dlm_print_one_lock_resource(res);
		goto leave;
	}

	/* found the lock */
	lksb = lock->lksb;

	/* see if caller needed to get/put lvb */
	if (flags & LKM_PUT_LVB) {
		BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
		lksb->flags |= DLM_LKSB_PUT_LVB;
		memcpy(&lksb->lvb[0], &cnv->lvb[0], DLM_LVB_LEN);
	} else if (flags & LKM_GET_LVB) {
		BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
		lksb->flags |= DLM_LKSB_GET_LVB;
	}

	spin_lock(&res->spinlock);
	status = __dlm_lockres_state_to_status(res);
	if (status == DLM_NORMAL) {
		__dlm_lockres_reserve_ast(res);
		ast_reserved = 1;
		res->state |= DLM_LOCK_RES_IN_PROGRESS;
		status = __dlmconvert_master(dlm, res, lock, flags,
					     cnv->requested_type,
					     &call_ast, &kick_thread);
		res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
		wake = 1;
	}
	spin_unlock(&res->spinlock);
	if (wake)
		wake_up(&res->wq);

	if (status != DLM_NORMAL) {
		if (status != DLM_NOTQUEUED)
			dlm_error(status);
		lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
	}

leave:
	if (lock)
		dlm_lock_put(lock);

	/* either queue the ast or release it, if reserved */
	if (call_ast)
		dlm_queue_ast(dlm, lock);
	else if (ast_reserved)
		dlm_lockres_release_ast(dlm, res);

	if (kick_thread)
		dlm_kick_thread(dlm, res);

	if (res)
		dlm_lockres_put(res);

	dlm_put(dlm);

	return status;
}
Commit	Line	Data
6714d8e8 KH	1	/* -- mode: c; c-basic-offset: 8; --
	2	* vim: noexpandtab sw=8 ts=8 sts=0:
	3	*
	4	* dlmconvert.c
	5	*
	6	* underlying calls for lock conversion
	7	*
	8	* Copyright (C) 2004 Oracle. All rights reserved.
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public
	12	* License as published by the Free Software Foundation; either
	13	* version 2 of the License, or (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public
	21	* License along with this program; if not, write to the
	22	* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	23	* Boston, MA 021110-1307, USA.
	24	*
	25	*/
	26
	27
	28	#include <linux/module.h>
	29	#include <linux/fs.h>
	30	#include <linux/types.h>
6714d8e8	31	#include <linux/highmem.h>
6714d8e8 KH	32	#include <linux/init.h>
	33	#include <linux/sysctl.h>
	34	#include <linux/random.h>
	35	#include <linux/blkdev.h>
	36	#include <linux/socket.h>
	37	#include <linux/inet.h>
	38	#include <linux/spinlock.h>
	39
	40
	41	#include "cluster/heartbeat.h"
	42	#include "cluster/nodemanager.h"
	43	#include "cluster/tcp.h"
	44
	45	#include "dlmapi.h"
	46	#include "dlmcommon.h"
	47
	48	#include "dlmconvert.h"
	49
	50	#define MLOG_MASK_PREFIX ML_DLM
	51	#include "cluster/masklog.h"
	52
	53	/* NOTE: __dlmconvert_master is the only function in here that
	54	* needs a spinlock held on entry (res->spinlock) and it is the
	55	* only one that holds a lock on exit (res->spinlock).
	56	* All other functions in here need no locks and drop all of
	57	* the locks that they acquire. */
	58	static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
	59	struct dlm_lock_resource *res,
	60	struct dlm_lock *lock, int flags,
	61	int type, int *call_ast,
	62	int *kick_thread);
	63	static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
	64	struct dlm_lock_resource *res,
	65	struct dlm_lock *lock, int flags, int type);
	66
	67	/*
	68	* this is only called directly by dlmlock(), and only when the
	69	* local node is the owner of the lockres
	70	* locking:
	71	* caller needs: none
	72	* taken: takes and drops res->spinlock
	73	* held on exit: none
	74	* returns: see __dlmconvert_master
	75	*/
	76	enum dlm_status dlmconvert_master(struct dlm_ctxt *dlm,
	77	struct dlm_lock_resource *res,
	78	struct dlm_lock *lock, int flags, int type)
	79	{
	80	int call_ast = 0, kick_thread = 0;
	81	enum dlm_status status;
	82
	83	spin_lock(&res->spinlock);
	84	/* we are not in a network handler, this is fine */
	85	__dlm_wait_on_lockres(res);
	86	__dlm_lockres_reserve_ast(res);
	87	res->state \|= DLM_LOCK_RES_IN_PROGRESS;
	88
	89	status = __dlmconvert_master(dlm, res, lock, flags, type,
	90	&call_ast, &kick_thread);
	91
	92	res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
	93	spin_unlock(&res->spinlock);
	94	wake_up(&res->wq);
	95	if (status != DLM_NORMAL && status != DLM_NOTQUEUED)
96	dlm_error(status);
97
98	/* either queue the ast or release it */
99	if (call_ast)
100	dlm_queue_ast(dlm, lock);
101	else
102	dlm_lockres_release_ast(dlm, res);
103
104	if (kick_thread)
105	dlm_kick_thread(dlm, res);
106
107	return status;
108	}
109
110	/* performs lock conversion at the lockres master site
111	* locking:
112	* caller needs: res->spinlock
113	* taken: takes and drops lock->spinlock
114	* held on exit: res->spinlock
115	* returns: DLM_NORMAL, DLM_NOTQUEUED, DLM_DENIED
116	* call_ast: whether ast should be called for this lock
117	* kick_thread: whether dlm_kick_thread should be called
118	*/
119	static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
120	struct dlm_lock_resource *res,
121	struct dlm_lock *lock, int flags,
122	int type, int *call_ast,
123	int *kick_thread)
124	{
125	enum dlm_status status = DLM_NORMAL;
6714d8e8 KH	126	struct dlm_lock *tmplock=NULL;
	127
	128	assert_spin_locked(&res->spinlock);
	129
ef6b689b TM	130	mlog(0, "type=%d, convert_type=%d, new convert_type=%d\n",
ef6b689b TM	131	lock->ml.type, lock->ml.convert_type, type);
6714d8e8 KH	132
	133	spin_lock(&lock->spinlock);
	134
	135	/* already converting? */
	136	if (lock->ml.convert_type != LKM_IVMODE) {
	137	mlog(ML_ERROR, "attempted to convert a lock with a lock "
	138	"conversion pending\n");
	139	status = DLM_DENIED;
	140	goto unlock_exit;
	141	}
	142
	143	/* must be on grant queue to convert */
	144	if (!dlm_lock_on_list(&res->granted, lock)) {
	145	mlog(ML_ERROR, "attempted to convert a lock not on grant "
	146	"queue\n");
	147	status = DLM_DENIED;
	148	goto unlock_exit;
	149	}
	150
	151	if (flags & LKM_VALBLK) {
	152	switch (lock->ml.type) {
	153	case LKM_EXMODE:
	154	/* EX + LKM_VALBLK + convert == set lvb */
	155	mlog(0, "will set lvb: converting %s->%s\n",
	156	dlm_lock_mode_name(lock->ml.type),
	157	dlm_lock_mode_name(type));
	158	lock->lksb->flags \|= DLM_LKSB_PUT_LVB;
	159	break;
	160	case LKM_PRMODE:
	161	case LKM_NLMODE:
	162	/* refetch if new level is not NL */
	163	if (type > LKM_NLMODE) {
	164	mlog(0, "will fetch new value into "
	165	"lvb: converting %s->%s\n",
	166	dlm_lock_mode_name(lock->ml.type),
	167	dlm_lock_mode_name(type));
	168	lock->lksb->flags \|= DLM_LKSB_GET_LVB;
	169	} else {
	170	mlog(0, "will NOT fetch new value "
	171	"into lvb: converting %s->%s\n",
	172	dlm_lock_mode_name(lock->ml.type),
	173	dlm_lock_mode_name(type));
	174	flags &= ~(LKM_VALBLK);
	175	}
	176	break;
	177	}
	178	}
	179
	180
	181	/* in-place downconvert? */
	182	if (type <= lock->ml.type)
	183	goto grant;
	184
	185	/* upconvert from here on */
	186	status = DLM_NORMAL;
df53cd3b	187	list_for_each_entry(tmplock, &res->granted, list) {
6714d8e8 KH	188	if (tmplock == lock)
	189	continue;
	190	if (!dlm_lock_compatible(tmplock->ml.type, type))
	191	goto switch_queues;
	192	}
	193
df53cd3b	194	list_for_each_entry(tmplock, &res->converting, list) {
6714d8e8 KH	195	if (!dlm_lock_compatible(tmplock->ml.type, type))
	196	goto switch_queues;
	197	/* existing conversion requests take precedence */
	198	if (!dlm_lock_compatible(tmplock->ml.convert_type, type))
	199	goto switch_queues;
	200	}
	201
	202	/* fall thru to grant */
	203
	204	grant:
	205	mlog(0, "res %.*s, granting %s lock\n", res->lockname.len,
	206	res->lockname.name, dlm_lock_mode_name(type));
	207	/* immediately grant the new lock type */
	208	lock->lksb->status = DLM_NORMAL;
	209	if (lock->ml.node == dlm->node_num)
	210	mlog(0, "doing in-place convert for nonlocal lock\n");
	211	lock->ml.type = type;
c0a8520c MF	212	if (lock->lksb->flags & DLM_LKSB_PUT_LVB)
	213	memcpy(res->lvb, lock->lksb->lvb, DLM_LVB_LEN);
	214
e5054c9a	215	/*
	216	* Move the lock to the tail because it may be the only lock which has
	217	* an invalid lvb.
	218	*/
	219	list_move_tail(&lock->list, &res->granted);
	220
6714d8e8 KH	221	status = DLM_NORMAL;
	222	*call_ast = 1;
	223	goto unlock_exit;
	224
	225	switch_queues:
	226	if (flags & LKM_NOQUEUE) {
	227	mlog(0, "failed to convert NOQUEUE lock %.*s from "
	228	"%d to %d...\n", res->lockname.len, res->lockname.name,
	229	lock->ml.type, type);
	230	status = DLM_NOTQUEUED;
	231	goto unlock_exit;
	232	}
	233	mlog(0, "res %.*s, queueing...\n", res->lockname.len,
	234	res->lockname.name);
	235
	236	lock->ml.convert_type = type;
	237	/* do not alter lock refcount. switching lists. */
f116629d	238	list_move_tail(&lock->list, &res->converting);
6714d8e8 KH	239
	240	unlock_exit:
	241	spin_unlock(&lock->spinlock);
	242	if (status == DLM_DENIED) {
	243	__dlm_print_one_lock_resource(res);
	244	}
	245	if (status == DLM_NORMAL)
	246	*kick_thread = 1;
	247	return status;
	248	}
	249
	250	void dlm_revert_pending_convert(struct dlm_lock_resource *res,
	251	struct dlm_lock *lock)
	252	{
	253	/* do not alter lock refcount. switching lists. */
f116629d	254	list_move_tail(&lock->list, &res->granted);
6714d8e8 KH	255	lock->ml.convert_type = LKM_IVMODE;
	256	lock->lksb->flags &= ~(DLM_LKSB_GET_LVB\|DLM_LKSB_PUT_LVB);
	257	}
	258
	259	/* messages the master site to do lock conversion
	260	* locking:
	261	* caller needs: none
	262	* taken: takes and drops res->spinlock, uses DLM_LOCK_RES_IN_PROGRESS
	263	* held on exit: none
	264	* returns: DLM_NORMAL, DLM_RECOVERING, status from remote node
	265	*/
	266	enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
	267	struct dlm_lock_resource *res,
	268	struct dlm_lock *lock, int flags, int type)
	269	{
	270	enum dlm_status status;
	271
	272	mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type,
	273	lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS);
	274
	275	spin_lock(&res->spinlock);
	276	if (res->state & DLM_LOCK_RES_RECOVERING) {
	277	mlog(0, "bailing out early since res is RECOVERING "
	278	"on secondary queue\n");
	279	/* __dlm_print_one_lock_resource(res); */
	280	status = DLM_RECOVERING;
	281	goto bail;
	282	}
	283	/* will exit this call with spinlock held */
	284	__dlm_wait_on_lockres(res);
	285
	286	if (lock->ml.convert_type != LKM_IVMODE) {
	287	__dlm_print_one_lock_resource(res);
	288	mlog(ML_ERROR, "converting a remote lock that is already "
29004858	289	"converting! (cookie=%u:%llu, conv=%d)\n",
74aa2585 KH	290	dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
74aa2585 KH	291	dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
29004858	292	lock->ml.convert_type);
6714d8e8 KH	293	status = DLM_DENIED;
	294	goto bail;
	295	}
be12b299 JQ	296
	297	if (lock->ml.type == type && lock->ml.convert_type == LKM_IVMODE) {
	298	mlog(0, "last convert request returned DLM_RECOVERING, but "
	299	"owner has already queued and sent ast to me. res %.*s, "
	300	"(cookie=%u:%llu, type=%d, conv=%d)\n",
	301	res->lockname.len, res->lockname.name,
	302	dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
	303	dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
	304	lock->ml.type, lock->ml.convert_type);
	305	status = DLM_NORMAL;
	306	goto bail;
	307	}
	308
6714d8e8 KH	309	res->state \|= DLM_LOCK_RES_IN_PROGRESS;
	310	/* move lock to local convert queue */
	311	/* do not alter lock refcount. switching lists. */
f116629d	312	list_move_tail(&lock->list, &res->converting);
6714d8e8 KH	313	lock->convert_pending = 1;
	314	lock->ml.convert_type = type;
	315
	316	if (flags & LKM_VALBLK) {
	317	if (lock->ml.type == LKM_EXMODE) {
	318	flags \|= LKM_PUT_LVB;
	319	lock->lksb->flags \|= DLM_LKSB_PUT_LVB;
	320	} else {
	321	if (lock->ml.convert_type == LKM_NLMODE)
	322	flags &= ~LKM_VALBLK;
	323	else {
	324	flags \|= LKM_GET_LVB;
	325	lock->lksb->flags \|= DLM_LKSB_GET_LVB;
	326	}
	327	}
	328	}
	329	spin_unlock(&res->spinlock);
	330
	331	/* no locks held here.
	332	* need to wait for a reply as to whether it got queued or not. */
	333	status = dlm_send_remote_convert_request(dlm, res, lock, flags, type);
	334
	335	spin_lock(&res->spinlock);
	336	res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
ac7cf246 JQ	337	/* if it failed, move it back to granted queue.
	338	* if master returns DLM_NORMAL and then down before sending ast,
	339	* it may have already been moved to granted queue, reset to
	340	* DLM_RECOVERING and retry convert */
6714d8e8 KH	341	if (status != DLM_NORMAL) {
	342	if (status != DLM_NOTQUEUED)
	343	dlm_error(status);
	344	dlm_revert_pending_convert(res, lock);
e6f0c6e6 JQ	345	} else if (!lock->convert_pending) {
	346	mlog(0, "%s: res %.*s, owner died and lock has been moved back "
	347	"to granted list, retry convert.\n",
	348	dlm->name, res->lockname.len, res->lockname.name);
ac7cf246	349	status = DLM_RECOVERING;
6714d8e8	350	}
e6f0c6e6 JQ	351
e6f0c6e6 JQ	352	lock->convert_pending = 0;
6714d8e8 KH	353	bail:
	354	spin_unlock(&res->spinlock);
	355
	356	/* TODO: should this be a wake_one? */
	357	/* wake up any IN_PROGRESS waiters */
	358	wake_up(&res->wq);
	359
	360	return status;
	361	}
	362
	363	/* sends DLM_CONVERT_LOCK_MSG to master site
	364	* locking:
	365	* caller needs: none
	366	* taken: none
	367	* held on exit: none
	368	* returns: DLM_NOLOCKMGR, status from remote node
	369	*/
	370	static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
	371	struct dlm_lock_resource *res,
	372	struct dlm_lock *lock, int flags, int type)
	373	{
	374	struct dlm_convert_lock convert;
	375	int tmpret;
	376	enum dlm_status ret;
	377	int status = 0;
	378	struct kvec vec[2];
	379	size_t veclen = 1;
	380
ef6b689b	381	mlog(0, "%.*s\n", res->lockname.len, res->lockname.name);
6714d8e8 KH	382
	383	memset(&convert, 0, sizeof(struct dlm_convert_lock));
	384	convert.node_idx = dlm->node_num;
	385	convert.requested_type = type;
	386	convert.cookie = lock->ml.cookie;
	387	convert.namelen = res->lockname.len;
	388	convert.flags = cpu_to_be32(flags);
	389	memcpy(convert.name, res->lockname.name, convert.namelen);
	390
	391	vec[0].iov_len = sizeof(struct dlm_convert_lock);
	392	vec[0].iov_base = &convert;
	393
	394	if (flags & LKM_PUT_LVB) {
	395	/* extra data to send if we are updating lvb */
	396	vec[1].iov_len = DLM_LVB_LEN;
	397	vec[1].iov_base = lock->lksb->lvb;
	398	veclen++;
	399	}
	400
	401	tmpret = o2net_send_message_vec(DLM_CONVERT_LOCK_MSG, dlm->key,
	402	vec, veclen, res->owner, &status);
	403	if (tmpret >= 0) {
	404	// successfully sent and received
	405	ret = status; // this is already a dlm_status
	406	if (ret == DLM_RECOVERING) {
	407	mlog(0, "node %u returned DLM_RECOVERING from convert "
	408	"message!\n", res->owner);
	409	} else if (ret == DLM_MIGRATING) {
	410	mlog(0, "node %u returned DLM_MIGRATING from convert "
	411	"message!\n", res->owner);
	412	} else if (ret == DLM_FORWARD) {
	413	mlog(0, "node %u returned DLM_FORWARD from convert "
	414	"message!\n", res->owner);
	415	} else if (ret != DLM_NORMAL && ret != DLM_NOTQUEUED)
	416	dlm_error(ret);
	417	} else {
a5196ec5 WW	418	mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
	419	"node %u\n", tmpret, DLM_CONVERT_LOCK_MSG, dlm->key,
	420	res->owner);
6714d8e8	421	if (dlm_is_host_down(tmpret)) {
44465a7d KH	422	/* instead of logging the same network error over
	423	* and over, sleep here and wait for the heartbeat
	424	* to notice the node is dead. times out after 5s. */
2bd63216	425	dlm_wait_for_node_death(dlm, res->owner,
44465a7d	426	DLM_NODE_DEATH_WAIT_MAX);
6714d8e8 KH	427	ret = DLM_RECOVERING;
	428	mlog(0, "node %u died so returning DLM_RECOVERING "
	429	"from convert message!\n", res->owner);
	430	} else {
	431	ret = dlm_err_to_dlm_status(tmpret);
	432	}
	433	}
	434
	435	return ret;
	436	}
	437
	438	/* handler for DLM_CONVERT_LOCK_MSG on master site
	439	* locking:
	440	* caller needs: none
	441	* taken: takes and drop res->spinlock
	442	* held on exit: none
	443	* returns: DLM_NORMAL, DLM_IVLOCKID, DLM_BADARGS,
	444	* status from __dlmconvert_master
	445	*/
d74c9803 KH	446	int dlm_convert_lock_handler(struct o2net_msg msg, u32 len, void data,
d74c9803 KH	447	void **ret_data)
6714d8e8 KH	448	{
	449	struct dlm_ctxt *dlm = data;
	450	struct dlm_convert_lock cnv = (struct dlm_convert_lock )msg->buf;
	451	struct dlm_lock_resource *res = NULL;
6714d8e8	452	struct dlm_lock *lock = NULL;
df53cd3b	453	struct dlm_lock *tmp_lock;
6714d8e8 KH	454	struct dlm_lockstatus *lksb;
	455	enum dlm_status status = DLM_NORMAL;
	456	u32 flags;
a6fa3640	457	int call_ast = 0, kick_thread = 0, ast_reserved = 0, wake = 0;
6714d8e8 KH	458
	459	if (!dlm_grab(dlm)) {
	460	dlm_error(DLM_REJECTED);
	461	return DLM_REJECTED;
	462	}
	463
	464	mlog_bug_on_msg(!dlm_domain_fully_joined(dlm),
	465	"Domain %s not fully joined!\n", dlm->name);
	466
	467	if (cnv->namelen > DLM_LOCKID_NAME_MAX) {
	468	status = DLM_IVBUFLEN;
	469	dlm_error(status);
	470	goto leave;
	471	}
	472
	473	flags = be32_to_cpu(cnv->flags);
	474
	475	if ((flags & (LKM_PUT_LVB\|LKM_GET_LVB)) ==
	476	(LKM_PUT_LVB\|LKM_GET_LVB)) {
	477	mlog(ML_ERROR, "both PUT and GET lvb specified\n");
	478	status = DLM_BADARGS;
	479	goto leave;
	480	}
	481
	482	mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" :
	483	(flags & LKM_GET_LVB ? "get lvb" : "none"));
	484
	485	status = DLM_IVLOCKID;
	486	res = dlm_lookup_lockres(dlm, cnv->name, cnv->namelen);
	487	if (!res) {
	488	dlm_error(status);
	489	goto leave;
	490	}
	491
	492	spin_lock(&res->spinlock);
b220532a KH	493	status = __dlm_lockres_state_to_status(res);
	494	if (status != DLM_NORMAL) {
	495	spin_unlock(&res->spinlock);
	496	dlm_error(status);
	497	goto leave;
	498	}
df53cd3b DF	499	list_for_each_entry(tmp_lock, &res->granted, list) {
	500	if (tmp_lock->ml.cookie == cnv->cookie &&
	501	tmp_lock->ml.node == cnv->node_idx) {
	502	lock = tmp_lock;
6714d8e8 KH	503	dlm_lock_get(lock);
	504	break;
	505	}
6714d8e8 KH	506	}
	507	spin_unlock(&res->spinlock);
	508	if (!lock) {
	509	status = DLM_IVLOCKID;
90aaaf1c KH	510	mlog(ML_ERROR, "did not find lock to convert on grant queue! "
90aaaf1c KH	511	"cookie=%u:%llu\n",
74aa2585 KH	512	dlm_get_lock_cookie_node(be64_to_cpu(cnv->cookie)),
74aa2585 KH	513	dlm_get_lock_cookie_seq(be64_to_cpu(cnv->cookie)));
2af37ce8	514	dlm_print_one_lock_resource(res);
6714d8e8 KH	515	goto leave;
	516	}
	517
	518	/* found the lock */
	519	lksb = lock->lksb;
	520
	521	/* see if caller needed to get/put lvb */
	522	if (flags & LKM_PUT_LVB) {
	523	BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB\|DLM_LKSB_GET_LVB));
	524	lksb->flags \|= DLM_LKSB_PUT_LVB;
	525	memcpy(&lksb->lvb[0], &cnv->lvb[0], DLM_LVB_LEN);
	526	} else if (flags & LKM_GET_LVB) {
	527	BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB\|DLM_LKSB_GET_LVB));
	528	lksb->flags \|= DLM_LKSB_GET_LVB;
	529	}
	530
	531	spin_lock(&res->spinlock);
	532	status = __dlm_lockres_state_to_status(res);
	533	if (status == DLM_NORMAL) {
	534	__dlm_lockres_reserve_ast(res);
e2b5e450	535	ast_reserved = 1;
6714d8e8 KH	536	res->state \|= DLM_LOCK_RES_IN_PROGRESS;
	537	status = __dlmconvert_master(dlm, res, lock, flags,
	538	cnv->requested_type,
	539	&call_ast, &kick_thread);
	540	res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
a6fa3640	541	wake = 1;
6714d8e8 KH	542	}
6714d8e8 KH	543	spin_unlock(&res->spinlock);
a6fa3640 KH	544	if (wake)
a6fa3640 KH	545	wake_up(&res->wq);
6714d8e8 KH	546
	547	if (status != DLM_NORMAL) {
	548	if (status != DLM_NOTQUEUED)
	549	dlm_error(status);
	550	lksb->flags &= ~(DLM_LKSB_GET_LVB\|DLM_LKSB_PUT_LVB);
	551	}
	552
	553	leave:
90aaaf1c	554	if (lock)
6714d8e8 KH	555	dlm_lock_put(lock);
6714d8e8 KH	556
e2b5e450	557	/* either queue the ast or release it, if reserved */
6714d8e8 KH	558	if (call_ast)
6714d8e8 KH	559	dlm_queue_ast(dlm, lock);
e2b5e450	560	else if (ast_reserved)
6714d8e8 KH	561	dlm_lockres_release_ast(dlm, res);
	562
	563	if (kick_thread)
	564	dlm_kick_thread(dlm, res);
	565
	566	if (res)
	567	dlm_lockres_put(res);
	568
	569	dlm_put(dlm);
	570
	571	return status;
	572	}