[deliverable/linux.git] / fs / gfs2 / lock_dlm.c

/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2009 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 version 2.
 */

#include <linux/fs.h>
#include <linux/dlm.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/gfs2_ondisk.h>

#include "incore.h"
#include "glock.h"
#include "util.h"


static void gdlm_ast(void *arg)
{
	struct gfs2_glock *gl = arg;
	unsigned ret = gl->gl_state;

	BUG_ON(gl->gl_lksb.sb_flags & DLM_SBF_DEMOTED);

	if (gl->gl_lksb.sb_flags & DLM_SBF_VALNOTVALID)
		memset(gl->gl_lvb, 0, GDLM_LVB_SIZE);

	switch (gl->gl_lksb.sb_status) {
	case -DLM_EUNLOCK: /* Unlocked, so glock can be freed */
		call_rcu(&gl->gl_rcu, gfs2_glock_free);
		return;
	case -DLM_ECANCEL: /* Cancel while getting lock */
		ret |= LM_OUT_CANCELED;
		goto out;
	case -EAGAIN: /* Try lock fails */
	case -EDEADLK: /* Deadlock detected */
		goto out;
	case -ETIMEDOUT: /* Canceled due to timeout */
		ret |= LM_OUT_ERROR;
		goto out;
	case 0: /* Success */
		break;
	default: /* Something unexpected */
		BUG();
	}

	ret = gl->gl_req;
	if (gl->gl_lksb.sb_flags & DLM_SBF_ALTMODE) {
		if (gl->gl_req == LM_ST_SHARED)
			ret = LM_ST_DEFERRED;
		else if (gl->gl_req == LM_ST_DEFERRED)
			ret = LM_ST_SHARED;
		else
			BUG();
	}

	set_bit(GLF_INITIAL, &gl->gl_flags);
	gfs2_glock_complete(gl, ret);
	return;
out:
	if (!test_bit(GLF_INITIAL, &gl->gl_flags))
		gl->gl_lksb.sb_lkid = 0;
	gfs2_glock_complete(gl, ret);
}

static void gdlm_bast(void *arg, int mode)
{
	struct gfs2_glock *gl = arg;

	switch (mode) {
	case DLM_LOCK_EX:
		gfs2_glock_cb(gl, LM_ST_UNLOCKED);
		break;
	case DLM_LOCK_CW:
		gfs2_glock_cb(gl, LM_ST_DEFERRED);
		break;
	case DLM_LOCK_PR:
		gfs2_glock_cb(gl, LM_ST_SHARED);
		break;
	default:
		printk(KERN_ERR "unknown bast mode %d", mode);
		BUG();
	}
}

/* convert gfs lock-state to dlm lock-mode */

static int make_mode(const unsigned int lmstate)
{
	switch (lmstate) {
	case LM_ST_UNLOCKED:
		return DLM_LOCK_NL;
	case LM_ST_EXCLUSIVE:
		return DLM_LOCK_EX;
	case LM_ST_DEFERRED:
		return DLM_LOCK_CW;
	case LM_ST_SHARED:
		return DLM_LOCK_PR;
	}
	printk(KERN_ERR "unknown LM state %d", lmstate);
	BUG();
	return -1;
}

static u32 make_flags(const u32 lkid, const unsigned int gfs_flags,
		      const int req)
{
	u32 lkf = 0;

	if (gfs_flags & LM_FLAG_TRY)
		lkf |= DLM_LKF_NOQUEUE;

	if (gfs_flags & LM_FLAG_TRY_1CB) {
		lkf |= DLM_LKF_NOQUEUE;
		lkf |= DLM_LKF_NOQUEUEBAST;
	}

	if (gfs_flags & LM_FLAG_PRIORITY) {
		lkf |= DLM_LKF_NOORDER;
		lkf |= DLM_LKF_HEADQUE;
	}

	if (gfs_flags & LM_FLAG_ANY) {
		if (req == DLM_LOCK_PR)
			lkf |= DLM_LKF_ALTCW;
		else if (req == DLM_LOCK_CW)
			lkf |= DLM_LKF_ALTPR;
		else
			BUG();
	}

	if (lkid != 0) 
		lkf |= DLM_LKF_CONVERT;

	lkf |= DLM_LKF_VALBLK;

	return lkf;
}

static int gdlm_lock(struct gfs2_glock *gl, unsigned int req_state,
		     unsigned int flags)
{
	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
	int req;
	u32 lkf;

	req = make_mode(req_state);
	lkf = make_flags(gl->gl_lksb.sb_lkid, flags, req);

	/*
	 * Submit the actual lock request.
	 */

	return dlm_lock(ls->ls_dlm, req, &gl->gl_lksb, lkf, gl->gl_strname,
			GDLM_STRNAME_BYTES - 1, 0, gdlm_ast, gl, gdlm_bast);
}

static void gdlm_put_lock(struct gfs2_glock *gl)
{
	struct gfs2_sbd *sdp = gl->gl_sbd;
	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
	int error;

	if (gl->gl_lksb.sb_lkid == 0) {
		call_rcu(&gl->gl_rcu, gfs2_glock_free);
		return;
	}

	error = dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_VALBLK,
			   NULL, gl);
	if (error) {
		printk(KERN_ERR "gdlm_unlock %x,%llx err=%d\n",
		       gl->gl_name.ln_type,
		       (unsigned long long)gl->gl_name.ln_number, error);
		return;
	}
}

static void gdlm_cancel(struct gfs2_glock *gl)
{
	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
	dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_CANCEL, NULL, gl);
}

static int gdlm_mount(struct gfs2_sbd *sdp, const char *fsname)
{
	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
	int error;

	if (fsname == NULL) {
		fs_info(sdp, "no fsname found\n");
		return -EINVAL;
	}

	error = dlm_new_lockspace(fsname, strlen(fsname), &ls->ls_dlm,
				  DLM_LSFL_FS | DLM_LSFL_NEWEXCL |
				  (ls->ls_nodir ? DLM_LSFL_NODIR : 0),
				  GDLM_LVB_SIZE);
	if (error)
		printk(KERN_ERR "dlm_new_lockspace error %d", error);

	return error;
}

static void gdlm_unmount(struct gfs2_sbd *sdp)
{
	struct lm_lockstruct *ls = &sdp->sd_lockstruct;

	if (ls->ls_dlm) {
		dlm_release_lockspace(ls->ls_dlm, 2);
		ls->ls_dlm = NULL;
	}
}

static const match_table_t dlm_tokens = {
	{ Opt_jid, "jid=%d"},
	{ Opt_id, "id=%d"},
	{ Opt_first, "first=%d"},
	{ Opt_nodir, "nodir=%d"},
	{ Opt_err, NULL },
};

const struct lm_lockops gfs2_dlm_ops = {
	.lm_proto_name = "lock_dlm",
	.lm_mount = gdlm_mount,
	.lm_unmount = gdlm_unmount,
	.lm_put_lock = gdlm_put_lock,
	.lm_lock = gdlm_lock,
	.lm_cancel = gdlm_cancel,
	.lm_tokens = &dlm_tokens,
};
Commit	Line	Data
f057f6cd SW	1	/*
	2	* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
	3	* Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
	4	*
	5	* This copyrighted material is made available to anyone wishing to use,
	6	* modify, copy, or redistribute it subject to the terms and conditions
	7	* of the GNU General Public License version 2.
	8	*/
	9
	10	#include <linux/fs.h>
	11	#include <linux/dlm.h>
5a0e3ad6	12	#include <linux/slab.h>
f057f6cd SW	13	#include <linux/types.h>
	14	#include <linux/gfs2_ondisk.h>
	15
	16	#include "incore.h"
	17	#include "glock.h"
	18	#include "util.h"
	19
	20
	21	static void gdlm_ast(void *arg)
	22	{
	23	struct gfs2_glock *gl = arg;
	24	unsigned ret = gl->gl_state;
	25
	26	BUG_ON(gl->gl_lksb.sb_flags & DLM_SBF_DEMOTED);
	27
	28	if (gl->gl_lksb.sb_flags & DLM_SBF_VALNOTVALID)
	29	memset(gl->gl_lvb, 0, GDLM_LVB_SIZE);
	30
	31	switch (gl->gl_lksb.sb_status) {
	32	case -DLM_EUNLOCK: /* Unlocked, so glock can be freed */
bc015cb8	33	call_rcu(&gl->gl_rcu, gfs2_glock_free);
f057f6cd SW	34	return;
	35	case -DLM_ECANCEL: /* Cancel while getting lock */
	36	ret \|= LM_OUT_CANCELED;
	37	goto out;
	38	case -EAGAIN: /* Try lock fails */
1fea7c25	39	case -EDEADLK: /* Deadlock detected */
f057f6cd	40	goto out;
1fea7c25	41	case -ETIMEDOUT: /* Canceled due to timeout */
f057f6cd SW	42	ret \|= LM_OUT_ERROR;
	43	goto out;
	44	case 0: /* Success */
	45	break;
	46	default: /* Something unexpected */
	47	BUG();
	48	}
	49
02ffad08	50	ret = gl->gl_req;
f057f6cd	51	if (gl->gl_lksb.sb_flags & DLM_SBF_ALTMODE) {
02ffad08	52	if (gl->gl_req == LM_ST_SHARED)
f057f6cd	53	ret = LM_ST_DEFERRED;
02ffad08	54	else if (gl->gl_req == LM_ST_DEFERRED)
f057f6cd SW	55	ret = LM_ST_SHARED;
	56	else
	57	BUG();
	58	}
	59
	60	set_bit(GLF_INITIAL, &gl->gl_flags);
	61	gfs2_glock_complete(gl, ret);
	62	return;
	63	out:
	64	if (!test_bit(GLF_INITIAL, &gl->gl_flags))
	65	gl->gl_lksb.sb_lkid = 0;
	66	gfs2_glock_complete(gl, ret);
	67	}
	68
	69	static void gdlm_bast(void *arg, int mode)
	70	{
	71	struct gfs2_glock *gl = arg;
	72
	73	switch (mode) {
	74	case DLM_LOCK_EX:
	75	gfs2_glock_cb(gl, LM_ST_UNLOCKED);
	76	break;
	77	case DLM_LOCK_CW:
	78	gfs2_glock_cb(gl, LM_ST_DEFERRED);
	79	break;
	80	case DLM_LOCK_PR:
	81	gfs2_glock_cb(gl, LM_ST_SHARED);
	82	break;
	83	default:
	84	printk(KERN_ERR "unknown bast mode %d", mode);
	85	BUG();
	86	}
	87	}
	88
	89	/* convert gfs lock-state to dlm lock-mode */
	90
	91	static int make_mode(const unsigned int lmstate)
	92	{
	93	switch (lmstate) {
	94	case LM_ST_UNLOCKED:
	95	return DLM_LOCK_NL;
	96	case LM_ST_EXCLUSIVE:
	97	return DLM_LOCK_EX;
	98	case LM_ST_DEFERRED:
	99	return DLM_LOCK_CW;
	100	case LM_ST_SHARED:
	101	return DLM_LOCK_PR;
	102	}
	103	printk(KERN_ERR "unknown LM state %d", lmstate);
	104	BUG();
	105	return -1;
	106	}
	107
	108	static u32 make_flags(const u32 lkid, const unsigned int gfs_flags,
	109	const int req)
	110	{
	111	u32 lkf = 0;
	112
	113	if (gfs_flags & LM_FLAG_TRY)
	114	lkf \|= DLM_LKF_NOQUEUE;
	115
	116	if (gfs_flags & LM_FLAG_TRY_1CB) {
	117	lkf \|= DLM_LKF_NOQUEUE;
	118	lkf \|= DLM_LKF_NOQUEUEBAST;
119	}
120
121	if (gfs_flags & LM_FLAG_PRIORITY) {
122	lkf \|= DLM_LKF_NOORDER;
123	lkf \|= DLM_LKF_HEADQUE;
124	}
125
126	if (gfs_flags & LM_FLAG_ANY) {
127	if (req == DLM_LOCK_PR)
128	lkf \|= DLM_LKF_ALTCW;
129	else if (req == DLM_LOCK_CW)
130	lkf \|= DLM_LKF_ALTPR;
131	else
132	BUG();
133	}
134
135	if (lkid != 0)
136	lkf \|= DLM_LKF_CONVERT;
137
138	lkf \|= DLM_LKF_VALBLK;
139
140	return lkf;
141	}
142
921169ca SW	143	static int gdlm_lock(struct gfs2_glock *gl, unsigned int req_state,
921169ca SW	144	unsigned int flags)
f057f6cd SW	145	{
f057f6cd SW	146	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
f057f6cd SW	147	int req;
	148	u32 lkf;
	149
	150	req = make_mode(req_state);
	151	lkf = make_flags(gl->gl_lksb.sb_lkid, flags, req);
	152
	153	/*
	154	* Submit the actual lock request.
	155	*/
	156
921169ca SW	157	return dlm_lock(ls->ls_dlm, req, &gl->gl_lksb, lkf, gl->gl_strname,
921169ca SW	158	GDLM_STRNAME_BYTES - 1, 0, gdlm_ast, gl, gdlm_bast);
f057f6cd SW	159	}
f057f6cd SW	160
bc015cb8	161	static void gdlm_put_lock(struct gfs2_glock *gl)
f057f6cd	162	{
e402746a SW	163	struct gfs2_sbd *sdp = gl->gl_sbd;
e402746a SW	164	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
f057f6cd SW	165	int error;
	166
	167	if (gl->gl_lksb.sb_lkid == 0) {
bc015cb8	168	call_rcu(&gl->gl_rcu, gfs2_glock_free);
f057f6cd SW	169	return;
	170	}
	171
	172	error = dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_VALBLK,
	173	NULL, gl);
	174	if (error) {
	175	printk(KERN_ERR "gdlm_unlock %x,%llx err=%d\n",
	176	gl->gl_name.ln_type,
	177	(unsigned long long)gl->gl_name.ln_number, error);
	178	return;
	179	}
	180	}
	181
	182	static void gdlm_cancel(struct gfs2_glock *gl)
	183	{
	184	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
	185	dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_CANCEL, NULL, gl);
	186	}
	187
	188	static int gdlm_mount(struct gfs2_sbd sdp, const char fsname)
	189	{
	190	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
	191	int error;
	192
	193	if (fsname == NULL) {
	194	fs_info(sdp, "no fsname found\n");
	195	return -EINVAL;
	196	}
	197
	198	error = dlm_new_lockspace(fsname, strlen(fsname), &ls->ls_dlm,
	199	DLM_LSFL_FS \| DLM_LSFL_NEWEXCL \|
	200	(ls->ls_nodir ? DLM_LSFL_NODIR : 0),
	201	GDLM_LVB_SIZE);
	202	if (error)
	203	printk(KERN_ERR "dlm_new_lockspace error %d", error);
	204
	205	return error;
	206	}
	207
	208	static void gdlm_unmount(struct gfs2_sbd *sdp)
	209	{
	210	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
	211
	212	if (ls->ls_dlm) {
	213	dlm_release_lockspace(ls->ls_dlm, 2);
	214	ls->ls_dlm = NULL;
	215	}
	216	}
	217
	218	static const match_table_t dlm_tokens = {
	219	{ Opt_jid, "jid=%d"},
	220	{ Opt_id, "id=%d"},
	221	{ Opt_first, "first=%d"},
	222	{ Opt_nodir, "nodir=%d"},
	223	{ Opt_err, NULL },
	224	};
	225
	226	const struct lm_lockops gfs2_dlm_ops = {
	227	.lm_proto_name = "lock_dlm",
	228	.lm_mount = gdlm_mount,
	229	.lm_unmount = gdlm_unmount,
	230	.lm_put_lock = gdlm_put_lock,
	231	.lm_lock = gdlm_lock,
	232	.lm_cancel = gdlm_cancel,
233	.lm_tokens = &dlm_tokens,
234	};
235