[mirror_ubuntu-zesty-kernel.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/slab.h>
#include <linux/highmem.h>
#include <linux/utsname.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 list_head *iter;
	struct dlm_lock *tmplock=NULL;

	assert_spin_locked(&res->spinlock);

	mlog_entry("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(iter, &res->granted) {
		tmplock = list_entry(iter, struct dlm_lock, list);
		if (tmplock == lock)
			continue;
		if (!dlm_lock_compatible(tmplock->ml.type, type))
			goto switch_queues;
	}

	list_for_each(iter, &res->converting) {
		tmplock = list_entry(iter, struct dlm_lock, 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);

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