[net-next-2.6.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/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;
	struct gfs2_sbd *sdp = gl->gl_sbd;

	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 */
		if (gl->gl_ops->go_flags & GLOF_ASPACE)
			kmem_cache_free(gfs2_glock_aspace_cachep, gl);
		else
			kmem_cache_free(gfs2_glock_cachep, gl);
		if (atomic_dec_and_test(&sdp->sd_glock_disposal))
			wake_up(&sdp->sd_glock_wait);
		return;
	case -DLM_ECANCEL: /* Cancel while getting lock */
		ret |= LM_OUT_CANCELED;
		goto out;
	case -EAGAIN: /* Try lock fails */
		goto out;
	case -EINVAL: /* Invalid */
	case -ENOMEM: /* Out of memory */
		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 unsigned int gdlm_lock(struct gfs2_glock *gl,
			      unsigned int req_state, unsigned int flags)
{
	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
	int error;
	int req;
	u32 lkf;

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

	/*
	 * Submit the actual lock request.
	 */

	error = dlm_lock(ls->ls_dlm, req, &gl->gl_lksb, lkf, gl->gl_strname,
			 GDLM_STRNAME_BYTES - 1, 0, gdlm_ast, gl, gdlm_bast);
	if (error == -EAGAIN)
		return 0;
	if (error)
		return LM_OUT_ERROR;
	return LM_OUT_ASYNC;
}

static void gdlm_put_lock(struct kmem_cache *cachep, 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) {
		kmem_cache_free(cachep, gl);
		if (atomic_dec_and_test(&sdp->sd_glock_disposal))
			wake_up(&sdp->sd_glock_wait);
		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>
	12	#include <linux/types.h>
	13	#include <linux/gfs2_ondisk.h>
	14
	15	#include "incore.h"
	16	#include "glock.h"
	17	#include "util.h"
	18
	19
	20	static void gdlm_ast(void *arg)
	21	{
	22	struct gfs2_glock *gl = arg;
	23	unsigned ret = gl->gl_state;
e402746a	24	struct gfs2_sbd *sdp = gl->gl_sbd;
f057f6cd SW	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 */
009d8518 SW	33	if (gl->gl_ops->go_flags & GLOF_ASPACE)
	34	kmem_cache_free(gfs2_glock_aspace_cachep, gl);
	35	else
	36	kmem_cache_free(gfs2_glock_cachep, gl);
e402746a SW	37	if (atomic_dec_and_test(&sdp->sd_glock_disposal))
e402746a SW	38	wake_up(&sdp->sd_glock_wait);
f057f6cd SW	39	return;
	40	case -DLM_ECANCEL: /* Cancel while getting lock */
	41	ret \|= LM_OUT_CANCELED;
	42	goto out;
	43	case -EAGAIN: /* Try lock fails */
	44	goto out;
	45	case -EINVAL: /* Invalid */
	46	case -ENOMEM: /* Out of memory */
	47	ret \|= LM_OUT_ERROR;
	48	goto out;
	49	case 0: /* Success */
	50	break;
	51	default: /* Something unexpected */
	52	BUG();
	53	}
	54
02ffad08	55	ret = gl->gl_req;
f057f6cd	56	if (gl->gl_lksb.sb_flags & DLM_SBF_ALTMODE) {
02ffad08	57	if (gl->gl_req == LM_ST_SHARED)
f057f6cd	58	ret = LM_ST_DEFERRED;
02ffad08	59	else if (gl->gl_req == LM_ST_DEFERRED)
f057f6cd SW	60	ret = LM_ST_SHARED;
	61	else
	62	BUG();
	63	}
	64
	65	set_bit(GLF_INITIAL, &gl->gl_flags);
	66	gfs2_glock_complete(gl, ret);
	67	return;
	68	out:
	69	if (!test_bit(GLF_INITIAL, &gl->gl_flags))
	70	gl->gl_lksb.sb_lkid = 0;
	71	gfs2_glock_complete(gl, ret);
	72	}
	73
	74	static void gdlm_bast(void *arg, int mode)
	75	{
	76	struct gfs2_glock *gl = arg;
	77
	78	switch (mode) {
	79	case DLM_LOCK_EX:
	80	gfs2_glock_cb(gl, LM_ST_UNLOCKED);
	81	break;
	82	case DLM_LOCK_CW:
	83	gfs2_glock_cb(gl, LM_ST_DEFERRED);
	84	break;
	85	case DLM_LOCK_PR:
	86	gfs2_glock_cb(gl, LM_ST_SHARED);
	87	break;
	88	default:
	89	printk(KERN_ERR "unknown bast mode %d", mode);
	90	BUG();
	91	}
	92	}
	93
	94	/* convert gfs lock-state to dlm lock-mode */
	95
	96	static int make_mode(const unsigned int lmstate)
	97	{
	98	switch (lmstate) {
	99	case LM_ST_UNLOCKED:
	100	return DLM_LOCK_NL;
	101	case LM_ST_EXCLUSIVE:
	102	return DLM_LOCK_EX;
	103	case LM_ST_DEFERRED:
	104	return DLM_LOCK_CW;
	105	case LM_ST_SHARED:
	106	return DLM_LOCK_PR;
	107	}
	108	printk(KERN_ERR "unknown LM state %d", lmstate);
	109	BUG();
	110	return -1;
	111	}
	112
	113	static u32 make_flags(const u32 lkid, const unsigned int gfs_flags,
	114	const int req)
	115	{
	116	u32 lkf = 0;
	117
	118	if (gfs_flags & LM_FLAG_TRY)
	119	lkf \|= DLM_LKF_NOQUEUE;
	120
	121	if (gfs_flags & LM_FLAG_TRY_1CB) {
	122	lkf \|= DLM_LKF_NOQUEUE;
	123	lkf \|= DLM_LKF_NOQUEUEBAST;
124	}
125
126	if (gfs_flags & LM_FLAG_PRIORITY) {
127	lkf \|= DLM_LKF_NOORDER;
128	lkf \|= DLM_LKF_HEADQUE;
129	}
130
131	if (gfs_flags & LM_FLAG_ANY) {
132	if (req == DLM_LOCK_PR)
133	lkf \|= DLM_LKF_ALTCW;
134	else if (req == DLM_LOCK_CW)
135	lkf \|= DLM_LKF_ALTPR;
136	else
137	BUG();
138	}
139
140	if (lkid != 0)
141	lkf \|= DLM_LKF_CONVERT;
142
143	lkf \|= DLM_LKF_VALBLK;
144
145	return lkf;
146	}
147
148	static unsigned int gdlm_lock(struct gfs2_glock *gl,
149	unsigned int req_state, unsigned int flags)
150	{
151	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
152	int error;
153	int req;
154	u32 lkf;
155
02ffad08	156	gl->gl_req = req_state;
f057f6cd SW	157	req = make_mode(req_state);
	158	lkf = make_flags(gl->gl_lksb.sb_lkid, flags, req);
	159
	160	/*
	161	* Submit the actual lock request.
	162	*/
	163
	164	error = dlm_lock(ls->ls_dlm, req, &gl->gl_lksb, lkf, gl->gl_strname,
	165	GDLM_STRNAME_BYTES - 1, 0, gdlm_ast, gl, gdlm_bast);
	166	if (error == -EAGAIN)
	167	return 0;
	168	if (error)
	169	return LM_OUT_ERROR;
	170	return LM_OUT_ASYNC;
	171	}
	172
8f05228e	173	static void gdlm_put_lock(struct kmem_cache cachep, struct gfs2_glock gl)
f057f6cd	174	{
e402746a SW	175	struct gfs2_sbd *sdp = gl->gl_sbd;
e402746a SW	176	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
f057f6cd SW	177	int error;
	178
	179	if (gl->gl_lksb.sb_lkid == 0) {
	180	kmem_cache_free(cachep, gl);
8f05228e SW	181	if (atomic_dec_and_test(&sdp->sd_glock_disposal))
8f05228e SW	182	wake_up(&sdp->sd_glock_wait);
f057f6cd SW	183	return;
	184	}
	185
	186	error = dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_VALBLK,
	187	NULL, gl);
	188	if (error) {
	189	printk(KERN_ERR "gdlm_unlock %x,%llx err=%d\n",
	190	gl->gl_name.ln_type,
	191	(unsigned long long)gl->gl_name.ln_number, error);
	192	return;
	193	}
	194	}
	195
	196	static void gdlm_cancel(struct gfs2_glock *gl)
	197	{
	198	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
	199	dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_CANCEL, NULL, gl);
	200	}
	201
	202	static int gdlm_mount(struct gfs2_sbd sdp, const char fsname)
	203	{
	204	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
	205	int error;
	206
	207	if (fsname == NULL) {
	208	fs_info(sdp, "no fsname found\n");
	209	return -EINVAL;
	210	}
	211
	212	error = dlm_new_lockspace(fsname, strlen(fsname), &ls->ls_dlm,
	213	DLM_LSFL_FS \| DLM_LSFL_NEWEXCL \|
	214	(ls->ls_nodir ? DLM_LSFL_NODIR : 0),
	215	GDLM_LVB_SIZE);
	216	if (error)
	217	printk(KERN_ERR "dlm_new_lockspace error %d", error);
	218
	219	return error;
	220	}
	221
	222	static void gdlm_unmount(struct gfs2_sbd *sdp)
	223	{
	224	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
	225
	226	if (ls->ls_dlm) {
	227	dlm_release_lockspace(ls->ls_dlm, 2);
	228	ls->ls_dlm = NULL;
	229	}
	230	}
	231
	232	static const match_table_t dlm_tokens = {
	233	{ Opt_jid, "jid=%d"},
	234	{ Opt_id, "id=%d"},
	235	{ Opt_first, "first=%d"},
	236	{ Opt_nodir, "nodir=%d"},
	237	{ Opt_err, NULL },
	238	};
	239
	240	const struct lm_lockops gfs2_dlm_ops = {
	241	.lm_proto_name = "lock_dlm",
	242	.lm_mount = gdlm_mount,
	243	.lm_unmount = gdlm_unmount,
	244	.lm_put_lock = gdlm_put_lock,
	245	.lm_lock = gdlm_lock,
	246	.lm_cancel = gdlm_cancel,
247	.lm_tokens = &dlm_tokens,
248	};
249