fs/gfs2/trans.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/completion.h>
 #include <linux/buffer_head.h>
 #include <linux/kallsyms.h>
 #include <linux/gfs2_ondisk.h>

 #include "gfs2.h"
 #include "incore.h"
 #include "glock.h"
 #include "inode.h"
 #include "log.h"
 #include "lops.h"
 #include "meta_io.h"
 #include "trans.h"
 #include "util.h"
 #include "trace_gfs2.h"

 static void gfs2_print_trans(struct gfs2_sbd *sdp, const struct gfs2_trans *tr)
 {
 	fs_warn(sdp, "Transaction created at: %pSR\n", (void *)tr->tr_ip);
 	fs_warn(sdp, "blocks=%u revokes=%u reserved=%u touched=%u\n",
 		tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
 		test_bit(TR_TOUCHED, &tr->tr_flags));
 	fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u\n",
 		tr->tr_num_buf_new, tr->tr_num_buf_rm,
 		tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
 		tr->tr_num_revoke);
 }

 int __gfs2_trans_begin(struct gfs2_trans *tr, struct gfs2_sbd *sdp,
 		       unsigned int blocks, unsigned int revokes,
 		       unsigned long ip)
 {
 	unsigned int extra_revokes;

 	if (current->journal_info) {
 		gfs2_print_trans(sdp, current->journal_info);
 		BUG();
 	}
 	BUG_ON(blocks == 0 && revokes == 0);

 	if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
 		return -EROFS;

 	tr->tr_ip = ip;
 	tr->tr_blocks = blocks;
 	tr->tr_revokes = revokes;
 	tr->tr_reserved = GFS2_LOG_FLUSH_MIN_BLOCKS;
 	if (blocks) {
 		/*
 		 * The reserved blocks are either used for data or metadata.
 		 * We can have mixed data and metadata, each with its own log
 		 * descriptor block; see calc_reserved().
 		 */
 		tr->tr_reserved += blocks + 1 + DIV_ROUND_UP(blocks - 1, databuf_limit(sdp));
 	}
 	INIT_LIST_HEAD(&tr->tr_databuf);
 	INIT_LIST_HEAD(&tr->tr_buf);
 	INIT_LIST_HEAD(&tr->tr_list);
 	INIT_LIST_HEAD(&tr->tr_ail1_list);
 	INIT_LIST_HEAD(&tr->tr_ail2_list);

 	if (gfs2_assert_warn(sdp, tr->tr_reserved <= sdp->sd_jdesc->jd_blocks))
 		return -EINVAL;

 	sb_start_intwrite(sdp->sd_vfs);

 	/*
 	 * Try the reservations under sd_log_flush_lock to prevent log flushes
 	 * from creating inconsistencies between the number of allocated and
 	 * reserved revokes.  If that fails, do a full-block allocation outside
 	 * of the lock to avoid stalling log flushes.  Then, allot the
 	 * appropriate number of blocks to revokes, use as many revokes locally
 	 * as needed, and "release" the surplus into the revokes pool.
 	 */

 	down_read(&sdp->sd_log_flush_lock);
 	if (gfs2_log_try_reserve(sdp, tr, &extra_revokes))
 		goto reserved;
 	up_read(&sdp->sd_log_flush_lock);
 	gfs2_log_reserve(sdp, tr, &extra_revokes);
 	down_read(&sdp->sd_log_flush_lock);

 reserved:
 	gfs2_log_release_revokes(sdp, extra_revokes);
 	if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) {
 		gfs2_log_release_revokes(sdp, tr->tr_revokes);
 		up_read(&sdp->sd_log_flush_lock);
 		gfs2_log_release(sdp, tr->tr_reserved);
 		sb_end_intwrite(sdp->sd_vfs);
 		return -EROFS;
 	}

 	current->journal_info = tr;

 	return 0;
 }

 int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
 		     unsigned int revokes)
 {
 	struct gfs2_trans *tr;
 	int error;

 	tr = kmem_cache_zalloc(gfs2_trans_cachep, GFP_NOFS);
 	if (!tr)
 		return -ENOMEM;
 	error = __gfs2_trans_begin(tr, sdp, blocks, revokes, _RET_IP_);
 	if (error)
 		kmem_cache_free(gfs2_trans_cachep, tr);
 	return error;
 }

 void gfs2_trans_end(struct gfs2_sbd *sdp)
 {
 	struct gfs2_trans *tr = current->journal_info;
 	s64 nbuf;

 	current->journal_info = NULL;

 	if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
 		gfs2_log_release_revokes(sdp, tr->tr_revokes);
 		up_read(&sdp->sd_log_flush_lock);
 		gfs2_log_release(sdp, tr->tr_reserved);
 		if (!test_bit(TR_ONSTACK, &tr->tr_flags))
 			gfs2_trans_free(sdp, tr);
 		sb_end_intwrite(sdp->sd_vfs);
 		return;
 	}

 	gfs2_log_release_revokes(sdp, tr->tr_revokes - tr->tr_num_revoke);

 	nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
 	nbuf -= tr->tr_num_buf_rm;
 	nbuf -= tr->tr_num_databuf_rm;

 	if (gfs2_assert_withdraw(sdp, nbuf <= tr->tr_blocks) ||
 	    gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes))
 		gfs2_print_trans(sdp, tr);

 	gfs2_log_commit(sdp, tr);
 	if (!test_bit(TR_ONSTACK, &tr->tr_flags) &&
 	    !test_bit(TR_ATTACHED, &tr->tr_flags))
 		gfs2_trans_free(sdp, tr);
 	up_read(&sdp->sd_log_flush_lock);

 	if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
 		gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
 			       GFS2_LFC_TRANS_END);
 	sb_end_intwrite(sdp->sd_vfs);
 }

 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
 					       struct buffer_head *bh)
 {
 	struct gfs2_bufdata *bd;

 	bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
 	bd->bd_bh = bh;
 	bd->bd_gl = gl;
 	INIT_LIST_HEAD(&bd->bd_list);
 	bh->b_private = bd;
 	return bd;
 }

 /**
  * gfs2_trans_add_data - Add a databuf to the transaction.
  * @gl: The inode glock associated with the buffer
  * @bh: The buffer to add
  *
  * This is used in journaled data mode.
  * We need to journal the data block in the same way as metadata in
  * the functions above. The difference is that here we have a tag
  * which is two __be64's being the block number (as per meta data)
  * and a flag which says whether the data block needs escaping or
  * not. This means we need a new log entry for each 251 or so data
  * blocks, which isn't an enormous overhead but twice as much as
  * for normal metadata blocks.
  */
 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
 {
 	struct gfs2_trans *tr = current->journal_info;
 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct gfs2_bufdata *bd;

 	lock_buffer(bh);
 	if (buffer_pinned(bh)) {
 		set_bit(TR_TOUCHED, &tr->tr_flags);
 		goto out;
 	}
 	gfs2_log_lock(sdp);
 	bd = bh->b_private;
 	if (bd == NULL) {
 		gfs2_log_unlock(sdp);
 		unlock_buffer(bh);
 		if (bh->b_private == NULL)
 			bd = gfs2_alloc_bufdata(gl, bh);
 		else
 			bd = bh->b_private;
 		lock_buffer(bh);
 		gfs2_log_lock(sdp);
 	}
 	gfs2_assert(sdp, bd->bd_gl == gl);
 	set_bit(TR_TOUCHED, &tr->tr_flags);
 	if (list_empty(&bd->bd_list)) {
 		set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 		set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 		gfs2_pin(sdp, bd->bd_bh);
 		tr->tr_num_databuf_new++;
 		list_add_tail(&bd->bd_list, &tr->tr_databuf);
 	}
 	gfs2_log_unlock(sdp);
 out:
 	unlock_buffer(bh);
 }

 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
 {

 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct gfs2_bufdata *bd;
 	struct gfs2_meta_header *mh;
 	struct gfs2_trans *tr = current->journal_info;
 	enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);

 	lock_buffer(bh);
 	if (buffer_pinned(bh)) {
 		set_bit(TR_TOUCHED, &tr->tr_flags);
 		goto out;
 	}
 	gfs2_log_lock(sdp);
 	bd = bh->b_private;
 	if (bd == NULL) {
 		gfs2_log_unlock(sdp);
 		unlock_buffer(bh);
 		lock_page(bh->b_page);
 		if (bh->b_private == NULL)
 			bd = gfs2_alloc_bufdata(gl, bh);
 		else
 			bd = bh->b_private;
 		unlock_page(bh->b_page);
 		lock_buffer(bh);
 		gfs2_log_lock(sdp);
 	}
 	gfs2_assert(sdp, bd->bd_gl == gl);
 	set_bit(TR_TOUCHED, &tr->tr_flags);
 	if (!list_empty(&bd->bd_list))
 		goto out_unlock;
 	set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 	set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 	mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
 	if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
 		fs_err(sdp, "Attempting to add uninitialised block to "
 		       "journal (inplace block=%lld)\n",
 		       (unsigned long long)bd->bd_bh->b_blocknr);
 		BUG();
 	}
 	if (unlikely(state == SFS_FROZEN)) {
 		fs_info(sdp, "GFS2:adding buf while frozen\n");
 		gfs2_assert_withdraw(sdp, 0);
 	}
 	if (unlikely(gfs2_withdrawn(sdp))) {
 		fs_info(sdp, "GFS2:adding buf while withdrawn! 0x%llx\n",
 			(unsigned long long)bd->bd_bh->b_blocknr);
 	}
 	gfs2_pin(sdp, bd->bd_bh);
 	mh->__pad0 = cpu_to_be64(0);
 	mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
 	list_add(&bd->bd_list, &tr->tr_buf);
 	tr->tr_num_buf_new++;
 out_unlock:
 	gfs2_log_unlock(sdp);
 out:
 	unlock_buffer(bh);
 }

 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 {
 	struct gfs2_trans *tr = current->journal_info;

 	BUG_ON(!list_empty(&bd->bd_list));
 	gfs2_add_revoke(sdp, bd);
 	set_bit(TR_TOUCHED, &tr->tr_flags);
 	tr->tr_num_revoke++;
 }

 void gfs2_trans_remove_revoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
 {
 	struct gfs2_bufdata *bd, *tmp;
 	unsigned int n = len;

 	gfs2_log_lock(sdp);
 	list_for_each_entry_safe(bd, tmp, &sdp->sd_log_revokes, bd_list) {
 		if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
 			list_del_init(&bd->bd_list);
 			gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
 			sdp->sd_log_num_revoke--;
 			if (bd->bd_gl)
 				gfs2_glock_remove_revoke(bd->bd_gl);
 			kmem_cache_free(gfs2_bufdata_cachep, bd);
 			gfs2_log_release_revokes(sdp, 1);
 			if (--n == 0)
 				break;
 		}
 	}
 	gfs2_log_unlock(sdp);
 }

 void gfs2_trans_free(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 {
 	if (tr == NULL)
 		return;

 	gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
 	gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
 	gfs2_assert_warn(sdp, list_empty(&tr->tr_databuf));
 	gfs2_assert_warn(sdp, list_empty(&tr->tr_buf));
 	kmem_cache_free(gfs2_trans_cachep, tr);
 }
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
	* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/sched.h>
	#include <linux/slab.h>
	#include <linux/spinlock.h>
	#include <linux/completion.h>
	#include <linux/buffer_head.h>
	#include <linux/kallsyms.h>
	#include <linux/gfs2_ondisk.h>

	#include "gfs2.h"
	#include "incore.h"
	#include "glock.h"
	#include "inode.h"
	#include "log.h"
	#include "lops.h"
	#include "meta_io.h"
	#include "trans.h"
	#include "util.h"
	#include "trace_gfs2.h"

	static void gfs2_print_trans(struct gfs2_sbd sdp, const struct gfs2_trans tr)
	{
	fs_warn(sdp, "Transaction created at: %pSR\n", (void *)tr->tr_ip);
	fs_warn(sdp, "blocks=%u revokes=%u reserved=%u touched=%u\n",
	tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
	test_bit(TR_TOUCHED, &tr->tr_flags));
	fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u\n",
	tr->tr_num_buf_new, tr->tr_num_buf_rm,
	tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
	tr->tr_num_revoke);
	}

	int __gfs2_trans_begin(struct gfs2_trans tr, struct gfs2_sbd sdp,
	unsigned int blocks, unsigned int revokes,
	unsigned long ip)
	{
	unsigned int extra_revokes;

	if (current->journal_info) {
	gfs2_print_trans(sdp, current->journal_info);
	BUG();
	}
	BUG_ON(blocks == 0 && revokes == 0);

	if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
	return -EROFS;

	tr->tr_ip = ip;
	tr->tr_blocks = blocks;
	tr->tr_revokes = revokes;
	tr->tr_reserved = GFS2_LOG_FLUSH_MIN_BLOCKS;
	if (blocks) {
	/*
	* The reserved blocks are either used for data or metadata.
	* We can have mixed data and metadata, each with its own log
	* descriptor block; see calc_reserved().
	*/
	tr->tr_reserved += blocks + 1 + DIV_ROUND_UP(blocks - 1, databuf_limit(sdp));
	}
	INIT_LIST_HEAD(&tr->tr_databuf);
	INIT_LIST_HEAD(&tr->tr_buf);
	INIT_LIST_HEAD(&tr->tr_list);
	INIT_LIST_HEAD(&tr->tr_ail1_list);
	INIT_LIST_HEAD(&tr->tr_ail2_list);

	if (gfs2_assert_warn(sdp, tr->tr_reserved <= sdp->sd_jdesc->jd_blocks))
	return -EINVAL;

	sb_start_intwrite(sdp->sd_vfs);

	/*
	* Try the reservations under sd_log_flush_lock to prevent log flushes
	* from creating inconsistencies between the number of allocated and
	* reserved revokes. If that fails, do a full-block allocation outside
	* of the lock to avoid stalling log flushes. Then, allot the
	* appropriate number of blocks to revokes, use as many revokes locally
	* as needed, and "release" the surplus into the revokes pool.
	*/

	down_read(&sdp->sd_log_flush_lock);
	if (gfs2_log_try_reserve(sdp, tr, &extra_revokes))
	goto reserved;
	up_read(&sdp->sd_log_flush_lock);
	gfs2_log_reserve(sdp, tr, &extra_revokes);
	down_read(&sdp->sd_log_flush_lock);

	reserved:
	gfs2_log_release_revokes(sdp, extra_revokes);
	if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) {
	gfs2_log_release_revokes(sdp, tr->tr_revokes);
	up_read(&sdp->sd_log_flush_lock);
	gfs2_log_release(sdp, tr->tr_reserved);
	sb_end_intwrite(sdp->sd_vfs);
	return -EROFS;
	}

	current->journal_info = tr;

	return 0;
	}

	int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
	unsigned int revokes)
	{
	struct gfs2_trans *tr;
	int error;

	tr = kmem_cache_zalloc(gfs2_trans_cachep, GFP_NOFS);
	if (!tr)
	return -ENOMEM;
	error = __gfs2_trans_begin(tr, sdp, blocks, revokes, _RET_IP_);
	if (error)
	kmem_cache_free(gfs2_trans_cachep, tr);
	return error;
	}

	void gfs2_trans_end(struct gfs2_sbd *sdp)
	{
	struct gfs2_trans *tr = current->journal_info;
	s64 nbuf;

	current->journal_info = NULL;

	if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
	gfs2_log_release_revokes(sdp, tr->tr_revokes);
	up_read(&sdp->sd_log_flush_lock);
	gfs2_log_release(sdp, tr->tr_reserved);
	if (!test_bit(TR_ONSTACK, &tr->tr_flags))
	gfs2_trans_free(sdp, tr);
	sb_end_intwrite(sdp->sd_vfs);
	return;
	}

	gfs2_log_release_revokes(sdp, tr->tr_revokes - tr->tr_num_revoke);

	nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
	nbuf -= tr->tr_num_buf_rm;
	nbuf -= tr->tr_num_databuf_rm;

	if (gfs2_assert_withdraw(sdp, nbuf <= tr->tr_blocks) \|\|
	gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes))
	gfs2_print_trans(sdp, tr);

	gfs2_log_commit(sdp, tr);
	if (!test_bit(TR_ONSTACK, &tr->tr_flags) &&
	!test_bit(TR_ATTACHED, &tr->tr_flags))
	gfs2_trans_free(sdp, tr);
	up_read(&sdp->sd_log_flush_lock);

	if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
	gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL \|
	GFS2_LFC_TRANS_END);
	sb_end_intwrite(sdp->sd_vfs);
	}

	static struct gfs2_bufdata gfs2_alloc_bufdata(struct gfs2_glock gl,
	struct buffer_head *bh)
	{
	struct gfs2_bufdata *bd;

	bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS \| __GFP_NOFAIL);
	bd->bd_bh = bh;
	bd->bd_gl = gl;
	INIT_LIST_HEAD(&bd->bd_list);
	bh->b_private = bd;
	return bd;
	}

	/**
	* gfs2_trans_add_data - Add a databuf to the transaction.
	* @gl: The inode glock associated with the buffer
	* @bh: The buffer to add
	*
	* This is used in journaled data mode.
	* We need to journal the data block in the same way as metadata in
	* the functions above. The difference is that here we have a tag
	* which is two __be64's being the block number (as per meta data)
	* and a flag which says whether the data block needs escaping or
	* not. This means we need a new log entry for each 251 or so data
	* blocks, which isn't an enormous overhead but twice as much as
	* for normal metadata blocks.
	*/
	void gfs2_trans_add_data(struct gfs2_glock gl, struct buffer_head bh)
	{
	struct gfs2_trans *tr = current->journal_info;
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct gfs2_bufdata *bd;

	lock_buffer(bh);
	if (buffer_pinned(bh)) {
	set_bit(TR_TOUCHED, &tr->tr_flags);
	goto out;
	}
	gfs2_log_lock(sdp);
	bd = bh->b_private;
	if (bd == NULL) {
	gfs2_log_unlock(sdp);
	unlock_buffer(bh);
	if (bh->b_private == NULL)
	bd = gfs2_alloc_bufdata(gl, bh);
	else
	bd = bh->b_private;
	lock_buffer(bh);
	gfs2_log_lock(sdp);
	}
	gfs2_assert(sdp, bd->bd_gl == gl);
	set_bit(TR_TOUCHED, &tr->tr_flags);
	if (list_empty(&bd->bd_list)) {
	set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
	set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
	gfs2_pin(sdp, bd->bd_bh);
	tr->tr_num_databuf_new++;
	list_add_tail(&bd->bd_list, &tr->tr_databuf);
	}
	gfs2_log_unlock(sdp);
	out:
	unlock_buffer(bh);
	}

	void gfs2_trans_add_meta(struct gfs2_glock gl, struct buffer_head bh)
	{

	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct gfs2_bufdata *bd;
	struct gfs2_meta_header *mh;
	struct gfs2_trans *tr = current->journal_info;
	enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);

	lock_buffer(bh);
	if (buffer_pinned(bh)) {
	set_bit(TR_TOUCHED, &tr->tr_flags);
	goto out;
	}
	gfs2_log_lock(sdp);
	bd = bh->b_private;
	if (bd == NULL) {
	gfs2_log_unlock(sdp);
	unlock_buffer(bh);
	lock_page(bh->b_page);
	if (bh->b_private == NULL)
	bd = gfs2_alloc_bufdata(gl, bh);
	else
	bd = bh->b_private;
	unlock_page(bh->b_page);
	lock_buffer(bh);
	gfs2_log_lock(sdp);
	}
	gfs2_assert(sdp, bd->bd_gl == gl);
	set_bit(TR_TOUCHED, &tr->tr_flags);
	if (!list_empty(&bd->bd_list))
	goto out_unlock;
	set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
	set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
	mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
	if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
	fs_err(sdp, "Attempting to add uninitialised block to "
	"journal (inplace block=%lld)\n",
	(unsigned long long)bd->bd_bh->b_blocknr);
	BUG();
	}
	if (unlikely(state == SFS_FROZEN)) {
	fs_info(sdp, "GFS2:adding buf while frozen\n");
	gfs2_assert_withdraw(sdp, 0);
	}
	if (unlikely(gfs2_withdrawn(sdp))) {
	fs_info(sdp, "GFS2:adding buf while withdrawn! 0x%llx\n",
	(unsigned long long)bd->bd_bh->b_blocknr);
	}
	gfs2_pin(sdp, bd->bd_bh);
	mh->__pad0 = cpu_to_be64(0);
	mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
	list_add(&bd->bd_list, &tr->tr_buf);
	tr->tr_num_buf_new++;
	out_unlock:
	gfs2_log_unlock(sdp);
	out:
	unlock_buffer(bh);
	}

	void gfs2_trans_add_revoke(struct gfs2_sbd sdp, struct gfs2_bufdata bd)
	{
	struct gfs2_trans *tr = current->journal_info;

	BUG_ON(!list_empty(&bd->bd_list));
	gfs2_add_revoke(sdp, bd);
	set_bit(TR_TOUCHED, &tr->tr_flags);
	tr->tr_num_revoke++;
	}

	void gfs2_trans_remove_revoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
	{
	struct gfs2_bufdata bd, tmp;
	unsigned int n = len;

	gfs2_log_lock(sdp);
	list_for_each_entry_safe(bd, tmp, &sdp->sd_log_revokes, bd_list) {
	if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
	list_del_init(&bd->bd_list);
	gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
	sdp->sd_log_num_revoke--;
	if (bd->bd_gl)
	gfs2_glock_remove_revoke(bd->bd_gl);
	kmem_cache_free(gfs2_bufdata_cachep, bd);
	gfs2_log_release_revokes(sdp, 1);
	if (--n == 0)
	break;
	}
	}
	gfs2_log_unlock(sdp);
	}

	void gfs2_trans_free(struct gfs2_sbd sdp, struct gfs2_trans tr)
	{
	if (tr == NULL)
	return;

	gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
	gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
	gfs2_assert_warn(sdp, list_empty(&tr->tr_databuf));
	gfs2_assert_warn(sdp, list_empty(&tr->tr_buf));
	kmem_cache_free(gfs2_trans_cachep, tr);
	}