[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;
	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 */
	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 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>
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;
e402746a	25	struct gfs2_sbd *sdp = gl->gl_sbd;
f057f6cd SW	26
	27	BUG_ON(gl->gl_lksb.sb_flags & DLM_SBF_DEMOTED);
	28
	29	if (gl->gl_lksb.sb_flags & DLM_SBF_VALNOTVALID)
	30	memset(gl->gl_lvb, 0, GDLM_LVB_SIZE);
	31
	32	switch (gl->gl_lksb.sb_status) {
	33	case -DLM_EUNLOCK: /* Unlocked, so glock can be freed */
009d8518 SW	34	if (gl->gl_ops->go_flags & GLOF_ASPACE)
	35	kmem_cache_free(gfs2_glock_aspace_cachep, gl);
	36	else
	37	kmem_cache_free(gfs2_glock_cachep, gl);
e402746a SW	38	if (atomic_dec_and_test(&sdp->sd_glock_disposal))
e402746a SW	39	wake_up(&sdp->sd_glock_wait);
f057f6cd SW	40	return;
	41	case -DLM_ECANCEL: /* Cancel while getting lock */
	42	ret \|= LM_OUT_CANCELED;
	43	goto out;
	44	case -EAGAIN: /* Try lock fails */
1fea7c25	45	case -EDEADLK: /* Deadlock detected */
f057f6cd	46	goto out;
1fea7c25	47	case -ETIMEDOUT: /* Canceled due to timeout */
f057f6cd SW	48	ret \|= LM_OUT_ERROR;
	49	goto out;
	50	case 0: /* Success */
	51	break;
	52	default: /* Something unexpected */
	53	BUG();
	54	}
	55
02ffad08	56	ret = gl->gl_req;
f057f6cd	57	if (gl->gl_lksb.sb_flags & DLM_SBF_ALTMODE) {
02ffad08	58	if (gl->gl_req == LM_ST_SHARED)
f057f6cd	59	ret = LM_ST_DEFERRED;
02ffad08	60	else if (gl->gl_req == LM_ST_DEFERRED)
f057f6cd SW	61	ret = LM_ST_SHARED;
	62	else
	63	BUG();
	64	}
	65
	66	set_bit(GLF_INITIAL, &gl->gl_flags);
	67	gfs2_glock_complete(gl, ret);
	68	return;
	69	out:
	70	if (!test_bit(GLF_INITIAL, &gl->gl_flags))
	71	gl->gl_lksb.sb_lkid = 0;
	72	gfs2_glock_complete(gl, ret);
	73	}
	74
	75	static void gdlm_bast(void *arg, int mode)
	76	{
	77	struct gfs2_glock *gl = arg;
	78
	79	switch (mode) {
	80	case DLM_LOCK_EX:
	81	gfs2_glock_cb(gl, LM_ST_UNLOCKED);
	82	break;
	83	case DLM_LOCK_CW:
	84	gfs2_glock_cb(gl, LM_ST_DEFERRED);
	85	break;
	86	case DLM_LOCK_PR:
	87	gfs2_glock_cb(gl, LM_ST_SHARED);
	88	break;
	89	default:
	90	printk(KERN_ERR "unknown bast mode %d", mode);
	91	BUG();
	92	}
	93	}
	94
	95	/* convert gfs lock-state to dlm lock-mode */
	96
	97	static int make_mode(const unsigned int lmstate)
	98	{
	99	switch (lmstate) {
	100	case LM_ST_UNLOCKED:
	101	return DLM_LOCK_NL;
	102	case LM_ST_EXCLUSIVE:
	103	return DLM_LOCK_EX;
	104	case LM_ST_DEFERRED:
	105	return DLM_LOCK_CW;
	106	case LM_ST_SHARED:
	107	return DLM_LOCK_PR;
	108	}
	109	printk(KERN_ERR "unknown LM state %d", lmstate);
	110	BUG();
	111	return -1;
	112	}
	113
	114	static u32 make_flags(const u32 lkid, const unsigned int gfs_flags,
	115	const int req)
	116	{
	117	u32 lkf = 0;
	118
	119	if (gfs_flags & LM_FLAG_TRY)
	120	lkf \|= DLM_LKF_NOQUEUE;
	121
	122	if (gfs_flags & LM_FLAG_TRY_1CB) {
	123	lkf \|= DLM_LKF_NOQUEUE;
	124	lkf \|= DLM_LKF_NOQUEUEBAST;
125	}
126
127	if (gfs_flags & LM_FLAG_PRIORITY) {
128	lkf \|= DLM_LKF_NOORDER;
129	lkf \|= DLM_LKF_HEADQUE;
130	}
131
132	if (gfs_flags & LM_FLAG_ANY) {
133	if (req == DLM_LOCK_PR)
134	lkf \|= DLM_LKF_ALTCW;
135	else if (req == DLM_LOCK_CW)
136	lkf \|= DLM_LKF_ALTPR;
137	else
138	BUG();
139	}
140
141	if (lkid != 0)
142	lkf \|= DLM_LKF_CONVERT;
143
144	lkf \|= DLM_LKF_VALBLK;
145
146	return lkf;
147	}
148
921169ca SW	149	static int gdlm_lock(struct gfs2_glock *gl, unsigned int req_state,
921169ca SW	150	unsigned int flags)
f057f6cd SW	151	{
f057f6cd SW	152	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
f057f6cd SW	153	int req;
	154	u32 lkf;
	155
	156	req = make_mode(req_state);
	157	lkf = make_flags(gl->gl_lksb.sb_lkid, flags, req);
	158
	159	/*
	160	* Submit the actual lock request.
	161	*/
	162
921169ca SW	163	return dlm_lock(ls->ls_dlm, req, &gl->gl_lksb, lkf, gl->gl_strname,
921169ca SW	164	GDLM_STRNAME_BYTES - 1, 0, gdlm_ast, gl, gdlm_bast);
f057f6cd SW	165	}
f057f6cd SW	166
8f05228e	167	static void gdlm_put_lock(struct kmem_cache cachep, struct gfs2_glock gl)
f057f6cd	168	{
e402746a SW	169	struct gfs2_sbd *sdp = gl->gl_sbd;
e402746a SW	170	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
f057f6cd SW	171	int error;
	172
	173	if (gl->gl_lksb.sb_lkid == 0) {
	174	kmem_cache_free(cachep, gl);
8f05228e SW	175	if (atomic_dec_and_test(&sdp->sd_glock_disposal))
8f05228e SW	176	wake_up(&sdp->sd_glock_wait);
f057f6cd SW	177	return;
	178	}
	179
	180	error = dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_VALBLK,
	181	NULL, gl);
	182	if (error) {
	183	printk(KERN_ERR "gdlm_unlock %x,%llx err=%d\n",
	184	gl->gl_name.ln_type,
	185	(unsigned long long)gl->gl_name.ln_number, error);
	186	return;
	187	}
	188	}
	189
	190	static void gdlm_cancel(struct gfs2_glock *gl)
	191	{
	192	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
	193	dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_CANCEL, NULL, gl);
	194	}
	195
	196	static int gdlm_mount(struct gfs2_sbd sdp, const char fsname)
	197	{
	198	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
	199	int error;
	200
	201	if (fsname == NULL) {
	202	fs_info(sdp, "no fsname found\n");
	203	return -EINVAL;
	204	}
	205
	206	error = dlm_new_lockspace(fsname, strlen(fsname), &ls->ls_dlm,
	207	DLM_LSFL_FS \| DLM_LSFL_NEWEXCL \|
	208	(ls->ls_nodir ? DLM_LSFL_NODIR : 0),
	209	GDLM_LVB_SIZE);
	210	if (error)
	211	printk(KERN_ERR "dlm_new_lockspace error %d", error);
	212
	213	return error;
	214	}
	215
	216	static void gdlm_unmount(struct gfs2_sbd *sdp)
	217	{
	218	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
	219
	220	if (ls->ls_dlm) {
	221	dlm_release_lockspace(ls->ls_dlm, 2);
	222	ls->ls_dlm = NULL;
	223	}
	224	}
	225
	226	static const match_table_t dlm_tokens = {
	227	{ Opt_jid, "jid=%d"},
	228	{ Opt_id, "id=%d"},
	229	{ Opt_first, "first=%d"},
	230	{ Opt_nodir, "nodir=%d"},
	231	{ Opt_err, NULL },
	232	};
	233
	234	const struct lm_lockops gfs2_dlm_ops = {
	235	.lm_proto_name = "lock_dlm",
	236	.lm_mount = gdlm_mount,
	237	.lm_unmount = gdlm_unmount,
	238	.lm_put_lock = gdlm_put_lock,
	239	.lm_lock = gdlm_lock,
	240	.lm_cancel = gdlm_cancel,
241	.lm_tokens = &dlm_tokens,
242	};
243