[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/gfs2/super.c b/ap/os/linux/linux-3.4.x/fs/gfs2/super.c
new file mode 100644
index 0000000..6172fa7
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/gfs2/super.c
@@ -0,0 +1,1609 @@
+/*
+ * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
+ * Copyright (C) 2004-2007 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/bio.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/statfs.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/crc32.h>
+#include <linux/time.h>
+#include <linux/wait.h>
+#include <linux/writeback.h>
+#include <linux/backing-dev.h>
+
+#include "gfs2.h"
+#include "incore.h"
+#include "bmap.h"
+#include "dir.h"
+#include "glock.h"
+#include "glops.h"
+#include "inode.h"
+#include "log.h"
+#include "meta_io.h"
+#include "quota.h"
+#include "recovery.h"
+#include "rgrp.h"
+#include "super.h"
+#include "trans.h"
+#include "util.h"
+#include "sys.h"
+#include "xattr.h"
+
+#define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)
+
+enum {
+	Opt_lockproto,
+	Opt_locktable,
+	Opt_hostdata,
+	Opt_spectator,
+	Opt_ignore_local_fs,
+	Opt_localflocks,
+	Opt_localcaching,
+	Opt_debug,
+	Opt_nodebug,
+	Opt_upgrade,
+	Opt_acl,
+	Opt_noacl,
+	Opt_quota_off,
+	Opt_quota_account,
+	Opt_quota_on,
+	Opt_quota,
+	Opt_noquota,
+	Opt_suiddir,
+	Opt_nosuiddir,
+	Opt_data_writeback,
+	Opt_data_ordered,
+	Opt_meta,
+	Opt_discard,
+	Opt_nodiscard,
+	Opt_commit,
+	Opt_err_withdraw,
+	Opt_err_panic,
+	Opt_statfs_quantum,
+	Opt_statfs_percent,
+	Opt_quota_quantum,
+	Opt_barrier,
+	Opt_nobarrier,
+	Opt_error,
+};
+
+static const match_table_t tokens = {
+	{Opt_lockproto, "lockproto=%s"},
+	{Opt_locktable, "locktable=%s"},
+	{Opt_hostdata, "hostdata=%s"},
+	{Opt_spectator, "spectator"},
+	{Opt_spectator, "norecovery"},
+	{Opt_ignore_local_fs, "ignore_local_fs"},
+	{Opt_localflocks, "localflocks"},
+	{Opt_localcaching, "localcaching"},
+	{Opt_debug, "debug"},
+	{Opt_nodebug, "nodebug"},
+	{Opt_upgrade, "upgrade"},
+	{Opt_acl, "acl"},
+	{Opt_noacl, "noacl"},
+	{Opt_quota_off, "quota=off"},
+	{Opt_quota_account, "quota=account"},
+	{Opt_quota_on, "quota=on"},
+	{Opt_quota, "quota"},
+	{Opt_noquota, "noquota"},
+	{Opt_suiddir, "suiddir"},
+	{Opt_nosuiddir, "nosuiddir"},
+	{Opt_data_writeback, "data=writeback"},
+	{Opt_data_ordered, "data=ordered"},
+	{Opt_meta, "meta"},
+	{Opt_discard, "discard"},
+	{Opt_nodiscard, "nodiscard"},
+	{Opt_commit, "commit=%d"},
+	{Opt_err_withdraw, "errors=withdraw"},
+	{Opt_err_panic, "errors=panic"},
+	{Opt_statfs_quantum, "statfs_quantum=%d"},
+	{Opt_statfs_percent, "statfs_percent=%d"},
+	{Opt_quota_quantum, "quota_quantum=%d"},
+	{Opt_barrier, "barrier"},
+	{Opt_nobarrier, "nobarrier"},
+	{Opt_error, NULL}
+};
+
+/**
+ * gfs2_mount_args - Parse mount options
+ * @args: The structure into which the parsed options will be written
+ * @options: The options to parse
+ *
+ * Return: errno
+ */
+
+int gfs2_mount_args(struct gfs2_args *args, char *options)
+{
+	char *o;
+	int token;
+	substring_t tmp[MAX_OPT_ARGS];
+	int rv;
+
+	/* Split the options into tokens with the "," character and
+	   process them */
+
+	while (1) {
+		o = strsep(&options, ",");
+		if (o == NULL)
+			break;
+		if (*o == '\0')
+			continue;
+
+		token = match_token(o, tokens, tmp);
+		switch (token) {
+		case Opt_lockproto:
+			match_strlcpy(args->ar_lockproto, &tmp[0],
+				      GFS2_LOCKNAME_LEN);
+			break;
+		case Opt_locktable:
+			match_strlcpy(args->ar_locktable, &tmp[0],
+				      GFS2_LOCKNAME_LEN);
+			break;
+		case Opt_hostdata:
+			match_strlcpy(args->ar_hostdata, &tmp[0],
+				      GFS2_LOCKNAME_LEN);
+			break;
+		case Opt_spectator:
+			args->ar_spectator = 1;
+			break;
+		case Opt_ignore_local_fs:
+			/* Retained for backwards compat only */
+			break;
+		case Opt_localflocks:
+			args->ar_localflocks = 1;
+			break;
+		case Opt_localcaching:
+			/* Retained for backwards compat only */
+			break;
+		case Opt_debug:
+			if (args->ar_errors == GFS2_ERRORS_PANIC) {
+				printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
+				       "are mutually exclusive.\n");
+				return -EINVAL;
+			}
+			args->ar_debug = 1;
+			break;
+		case Opt_nodebug:
+			args->ar_debug = 0;
+			break;
+		case Opt_upgrade:
+			/* Retained for backwards compat only */
+			break;
+		case Opt_acl:
+			args->ar_posix_acl = 1;
+			break;
+		case Opt_noacl:
+			args->ar_posix_acl = 0;
+			break;
+		case Opt_quota_off:
+		case Opt_noquota:
+			args->ar_quota = GFS2_QUOTA_OFF;
+			break;
+		case Opt_quota_account:
+			args->ar_quota = GFS2_QUOTA_ACCOUNT;
+			break;
+		case Opt_quota_on:
+		case Opt_quota:
+			args->ar_quota = GFS2_QUOTA_ON;
+			break;
+		case Opt_suiddir:
+			args->ar_suiddir = 1;
+			break;
+		case Opt_nosuiddir:
+			args->ar_suiddir = 0;
+			break;
+		case Opt_data_writeback:
+			args->ar_data = GFS2_DATA_WRITEBACK;
+			break;
+		case Opt_data_ordered:
+			args->ar_data = GFS2_DATA_ORDERED;
+			break;
+		case Opt_meta:
+			args->ar_meta = 1;
+			break;
+		case Opt_discard:
+			args->ar_discard = 1;
+			break;
+		case Opt_nodiscard:
+			args->ar_discard = 0;
+			break;
+		case Opt_commit:
+			rv = match_int(&tmp[0], &args->ar_commit);
+			if (rv || args->ar_commit <= 0) {
+				printk(KERN_WARNING "GFS2: commit mount option requires a positive numeric argument\n");
+				return rv ? rv : -EINVAL;
+			}
+			break;
+		case Opt_statfs_quantum:
+			rv = match_int(&tmp[0], &args->ar_statfs_quantum);
+			if (rv || args->ar_statfs_quantum < 0) {
+				printk(KERN_WARNING "GFS2: statfs_quantum mount option requires a non-negative numeric argument\n");
+				return rv ? rv : -EINVAL;
+			}
+			break;
+		case Opt_quota_quantum:
+			rv = match_int(&tmp[0], &args->ar_quota_quantum);
+			if (rv || args->ar_quota_quantum <= 0) {
+				printk(KERN_WARNING "GFS2: quota_quantum mount option requires a positive numeric argument\n");
+				return rv ? rv : -EINVAL;
+			}
+			break;
+		case Opt_statfs_percent:
+			rv = match_int(&tmp[0], &args->ar_statfs_percent);
+			if (rv || args->ar_statfs_percent < 0 ||
+			    args->ar_statfs_percent > 100) {
+				printk(KERN_WARNING "statfs_percent mount option requires a numeric argument between 0 and 100\n");
+				return rv ? rv : -EINVAL;
+			}
+			break;
+		case Opt_err_withdraw:
+			args->ar_errors = GFS2_ERRORS_WITHDRAW;
+			break;
+		case Opt_err_panic:
+			if (args->ar_debug) {
+				printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
+					"are mutually exclusive.\n");
+				return -EINVAL;
+			}
+			args->ar_errors = GFS2_ERRORS_PANIC;
+			break;
+		case Opt_barrier:
+			args->ar_nobarrier = 0;
+			break;
+		case Opt_nobarrier:
+			args->ar_nobarrier = 1;
+			break;
+		case Opt_error:
+		default:
+			printk(KERN_WARNING "GFS2: invalid mount option: %s\n", o);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * gfs2_jindex_free - Clear all the journal index information
+ * @sdp: The GFS2 superblock
+ *
+ */
+
+void gfs2_jindex_free(struct gfs2_sbd *sdp)
+{
+	struct list_head list, *head;
+	struct gfs2_jdesc *jd;
+	struct gfs2_journal_extent *jext;
+
+	spin_lock(&sdp->sd_jindex_spin);
+	list_add(&list, &sdp->sd_jindex_list);
+	list_del_init(&sdp->sd_jindex_list);
+	sdp->sd_journals = 0;
+	spin_unlock(&sdp->sd_jindex_spin);
+
+	while (!list_empty(&list)) {
+		jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
+		head = &jd->extent_list;
+		while (!list_empty(head)) {
+			jext = list_entry(head->next,
+					  struct gfs2_journal_extent,
+					  extent_list);
+			list_del(&jext->extent_list);
+			kfree(jext);
+		}
+		list_del(&jd->jd_list);
+		iput(jd->jd_inode);
+		kfree(jd);
+	}
+}
+
+static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
+{
+	struct gfs2_jdesc *jd;
+	int found = 0;
+
+	list_for_each_entry(jd, head, jd_list) {
+		if (jd->jd_jid == jid) {
+			found = 1;
+			break;
+		}
+	}
+
+	if (!found)
+		jd = NULL;
+
+	return jd;
+}
+
+struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
+{
+	struct gfs2_jdesc *jd;
+
+	spin_lock(&sdp->sd_jindex_spin);
+	jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
+	spin_unlock(&sdp->sd_jindex_spin);
+
+	return jd;
+}
+
+int gfs2_jdesc_check(struct gfs2_jdesc *jd)
+{
+	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
+	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
+	u64 size = i_size_read(jd->jd_inode);
+
+	if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, 1 << 30))
+		return -EIO;
+
+	jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
+
+	if (gfs2_write_alloc_required(ip, 0, size)) {
+		gfs2_consist_inode(ip);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
+ * @sdp: the filesystem
+ *
+ * Returns: errno
+ */
+
+int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
+{
+	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
+	struct gfs2_glock *j_gl = ip->i_gl;
+	struct gfs2_holder t_gh;
+	struct gfs2_log_header_host head;
+	int error;
+
+	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
+	if (error)
+		return error;
+
+	j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
+
+	error = gfs2_find_jhead(sdp->sd_jdesc, &head);
+	if (error)
+		goto fail;
+
+	if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
+		gfs2_consist(sdp);
+		error = -EIO;
+		goto fail;
+	}
+
+	/*  Initialize some head of the log stuff  */
+	sdp->sd_log_sequence = head.lh_sequence + 1;
+	gfs2_log_pointers_init(sdp, head.lh_blkno);
+
+	error = gfs2_quota_init(sdp);
+	if (error)
+		goto fail;
+
+	set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
+
+	gfs2_glock_dq_uninit(&t_gh);
+
+	return 0;
+
+fail:
+	t_gh.gh_flags |= GL_NOCACHE;
+	gfs2_glock_dq_uninit(&t_gh);
+
+	return error;
+}
+
+void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
+{
+	const struct gfs2_statfs_change *str = buf;
+
+	sc->sc_total = be64_to_cpu(str->sc_total);
+	sc->sc_free = be64_to_cpu(str->sc_free);
+	sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
+}
+
+static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
+{
+	struct gfs2_statfs_change *str = buf;
+
+	str->sc_total = cpu_to_be64(sc->sc_total);
+	str->sc_free = cpu_to_be64(sc->sc_free);
+	str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
+}
+
+int gfs2_statfs_init(struct gfs2_sbd *sdp)
+{
+	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+	struct buffer_head *m_bh, *l_bh;
+	struct gfs2_holder gh;
+	int error;
+
+	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
+				   &gh);
+	if (error)
+		return error;
+
+	error = gfs2_meta_inode_buffer(m_ip, &m_bh);
+	if (error)
+		goto out;
+
+	if (sdp->sd_args.ar_spectator) {
+		spin_lock(&sdp->sd_statfs_spin);
+		gfs2_statfs_change_in(m_sc, m_bh->b_data +
+				      sizeof(struct gfs2_dinode));
+		spin_unlock(&sdp->sd_statfs_spin);
+	} else {
+		error = gfs2_meta_inode_buffer(l_ip, &l_bh);
+		if (error)
+			goto out_m_bh;
+
+		spin_lock(&sdp->sd_statfs_spin);
+		gfs2_statfs_change_in(m_sc, m_bh->b_data +
+				      sizeof(struct gfs2_dinode));
+		gfs2_statfs_change_in(l_sc, l_bh->b_data +
+				      sizeof(struct gfs2_dinode));
+		spin_unlock(&sdp->sd_statfs_spin);
+
+		brelse(l_bh);
+	}
+
+out_m_bh:
+	brelse(m_bh);
+out:
+	gfs2_glock_dq_uninit(&gh);
+	return 0;
+}
+
+void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
+			s64 dinodes)
+{
+	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct buffer_head *l_bh;
+	s64 x, y;
+	int need_sync = 0;
+	int error;
+
+	error = gfs2_meta_inode_buffer(l_ip, &l_bh);
+	if (error)
+		return;
+
+	gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
+
+	spin_lock(&sdp->sd_statfs_spin);
+	l_sc->sc_total += total;
+	l_sc->sc_free += free;
+	l_sc->sc_dinodes += dinodes;
+	gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
+	if (sdp->sd_args.ar_statfs_percent) {
+		x = 100 * l_sc->sc_free;
+		y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
+		if (x >= y || x <= -y)
+			need_sync = 1;
+	}
+	spin_unlock(&sdp->sd_statfs_spin);
+
+	brelse(l_bh);
+	if (need_sync)
+		gfs2_wake_up_statfs(sdp);
+}
+
+void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
+		   struct buffer_head *l_bh)
+{
+	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
+	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+
+	gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
+
+	spin_lock(&sdp->sd_statfs_spin);
+	m_sc->sc_total += l_sc->sc_total;
+	m_sc->sc_free += l_sc->sc_free;
+	m_sc->sc_dinodes += l_sc->sc_dinodes;
+	memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
+	memset(l_bh->b_data + sizeof(struct gfs2_dinode),
+	       0, sizeof(struct gfs2_statfs_change));
+	spin_unlock(&sdp->sd_statfs_spin);
+
+	gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
+	gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
+}
+
+int gfs2_statfs_sync(struct super_block *sb, int type)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
+	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+	struct gfs2_holder gh;
+	struct buffer_head *m_bh, *l_bh;
+	int error;
+
+	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
+				   &gh);
+	if (error)
+		return error;
+
+	error = gfs2_meta_inode_buffer(m_ip, &m_bh);
+	if (error)
+		goto out;
+
+	spin_lock(&sdp->sd_statfs_spin);
+	gfs2_statfs_change_in(m_sc, m_bh->b_data +
+			      sizeof(struct gfs2_dinode));
+	if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
+		spin_unlock(&sdp->sd_statfs_spin);
+		goto out_bh;
+	}
+	spin_unlock(&sdp->sd_statfs_spin);
+
+	error = gfs2_meta_inode_buffer(l_ip, &l_bh);
+	if (error)
+		goto out_bh;
+
+	error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
+	if (error)
+		goto out_bh2;
+
+	update_statfs(sdp, m_bh, l_bh);
+	sdp->sd_statfs_force_sync = 0;
+
+	gfs2_trans_end(sdp);
+
+out_bh2:
+	brelse(l_bh);
+out_bh:
+	brelse(m_bh);
+out:
+	gfs2_glock_dq_uninit(&gh);
+	return error;
+}
+
+struct lfcc {
+	struct list_head list;
+	struct gfs2_holder gh;
+};
+
+/**
+ * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
+ *                            journals are clean
+ * @sdp: the file system
+ * @state: the state to put the transaction lock into
+ * @t_gh: the hold on the transaction lock
+ *
+ * Returns: errno
+ */
+
+static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
+				    struct gfs2_holder *t_gh)
+{
+	struct gfs2_inode *ip;
+	struct gfs2_jdesc *jd;
+	struct lfcc *lfcc;
+	LIST_HEAD(list);
+	struct gfs2_log_header_host lh;
+	int error;
+
+	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+		lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
+		if (!lfcc) {
+			error = -ENOMEM;
+			goto out;
+		}
+		ip = GFS2_I(jd->jd_inode);
+		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
+		if (error) {
+			kfree(lfcc);
+			goto out;
+		}
+		list_add(&lfcc->list, &list);
+	}
+
+	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
+				   GL_NOCACHE, t_gh);
+
+	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+		error = gfs2_jdesc_check(jd);
+		if (error)
+			break;
+		error = gfs2_find_jhead(jd, &lh);
+		if (error)
+			break;
+		if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
+			error = -EBUSY;
+			break;
+		}
+	}
+
+	if (error)
+		gfs2_glock_dq_uninit(t_gh);
+
+out:
+	while (!list_empty(&list)) {
+		lfcc = list_entry(list.next, struct lfcc, list);
+		list_del(&lfcc->list);
+		gfs2_glock_dq_uninit(&lfcc->gh);
+		kfree(lfcc);
+	}
+	return error;
+}
+
+/**
+ * gfs2_freeze_fs - freezes the file system
+ * @sdp: the file system
+ *
+ * This function flushes data and meta data for all machines by
+ * acquiring the transaction log exclusively.  All journals are
+ * ensured to be in a clean state as well.
+ *
+ * Returns: errno
+ */
+
+int gfs2_freeze_fs(struct gfs2_sbd *sdp)
+{
+	int error = 0;
+
+	mutex_lock(&sdp->sd_freeze_lock);
+
+	if (!sdp->sd_freeze_count++) {
+		error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
+		if (error)
+			sdp->sd_freeze_count--;
+	}
+
+	mutex_unlock(&sdp->sd_freeze_lock);
+
+	return error;
+}
+
+/**
+ * gfs2_unfreeze_fs - unfreezes the file system
+ * @sdp: the file system
+ *
+ * This function allows the file system to proceed by unlocking
+ * the exclusively held transaction lock.  Other GFS2 nodes are
+ * now free to acquire the lock shared and go on with their lives.
+ *
+ */
+
+void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
+{
+	mutex_lock(&sdp->sd_freeze_lock);
+
+	if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
+		gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
+
+	mutex_unlock(&sdp->sd_freeze_lock);
+}
+
+void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
+{
+	struct gfs2_dinode *str = buf;
+
+	str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
+	str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
+	str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
+	str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
+	str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
+	str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
+	str->di_uid = cpu_to_be32(ip->i_inode.i_uid);
+	str->di_gid = cpu_to_be32(ip->i_inode.i_gid);
+	str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
+	str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
+	str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
+	str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
+	str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
+	str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
+
+	str->di_goal_meta = cpu_to_be64(ip->i_goal);
+	str->di_goal_data = cpu_to_be64(ip->i_goal);
+	str->di_generation = cpu_to_be64(ip->i_generation);
+
+	str->di_flags = cpu_to_be32(ip->i_diskflags);
+	str->di_height = cpu_to_be16(ip->i_height);
+	str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
+					     !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
+					     GFS2_FORMAT_DE : 0);
+	str->di_depth = cpu_to_be16(ip->i_depth);
+	str->di_entries = cpu_to_be32(ip->i_entries);
+
+	str->di_eattr = cpu_to_be64(ip->i_eattr);
+	str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
+	str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
+	str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
+}
+
+/**
+ * gfs2_write_inode - Make sure the inode is stable on the disk
+ * @inode: The inode
+ * @wbc: The writeback control structure
+ *
+ * Returns: errno
+ */
+
+static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
+	struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
+	struct backing_dev_info *bdi = metamapping->backing_dev_info;
+	int ret = 0;
+
+	if (wbc->sync_mode == WB_SYNC_ALL)
+		gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
+	if (bdi->dirty_exceeded)
+		gfs2_ail1_flush(sdp, wbc);
+	else
+		filemap_fdatawrite(metamapping);
+	if (wbc->sync_mode == WB_SYNC_ALL)
+		ret = filemap_fdatawait(metamapping);
+	if (ret)
+		mark_inode_dirty_sync(inode);
+	return ret;
+}
+
+/**
+ * gfs2_dirty_inode - check for atime updates
+ * @inode: The inode in question
+ * @flags: The type of dirty
+ *
+ * Unfortunately it can be called under any combination of inode
+ * glock and transaction lock, so we have to check carefully.
+ *
+ * At the moment this deals only with atime - it should be possible
+ * to expand that role in future, once a review of the locking has
+ * been carried out.
+ */
+
+static void gfs2_dirty_inode(struct inode *inode, int flags)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
+	struct buffer_head *bh;
+	struct gfs2_holder gh;
+	int need_unlock = 0;
+	int need_endtrans = 0;
+	int ret;
+
+	if (!(flags & (I_DIRTY_DATASYNC|I_DIRTY_SYNC)))
+		return;
+
+	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
+		ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+		if (ret) {
+			fs_err(sdp, "dirty_inode: glock %d\n", ret);
+			return;
+		}
+		need_unlock = 1;
+	}
+
+	if (current->journal_info == NULL) {
+		ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
+		if (ret) {
+			fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
+			goto out;
+		}
+		need_endtrans = 1;
+	}
+
+	ret = gfs2_meta_inode_buffer(ip, &bh);
+	if (ret == 0) {
+		gfs2_trans_add_bh(ip->i_gl, bh, 1);
+		gfs2_dinode_out(ip, bh->b_data);
+		brelse(bh);
+	}
+
+	if (need_endtrans)
+		gfs2_trans_end(sdp);
+out:
+	if (need_unlock)
+		gfs2_glock_dq_uninit(&gh);
+}
+
+/**
+ * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
+ * @sdp: the filesystem
+ *
+ * Returns: errno
+ */
+
+static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
+{
+	struct gfs2_holder t_gh;
+	int error;
+
+	flush_workqueue(gfs2_delete_workqueue);
+	gfs2_quota_sync(sdp->sd_vfs, 0, 1);
+	gfs2_statfs_sync(sdp->sd_vfs, 0);
+
+	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
+				   &t_gh);
+	if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
+		return error;
+
+	gfs2_meta_syncfs(sdp);
+	gfs2_log_shutdown(sdp);
+
+	clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
+
+	if (t_gh.gh_gl)
+		gfs2_glock_dq_uninit(&t_gh);
+
+	gfs2_quota_cleanup(sdp);
+
+	return error;
+}
+
+static int gfs2_umount_recovery_wait(void *word)
+{
+	schedule();
+	return 0;
+}
+
+/**
+ * gfs2_put_super - Unmount the filesystem
+ * @sb: The VFS superblock
+ *
+ */
+
+static void gfs2_put_super(struct super_block *sb)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	int error;
+	struct gfs2_jdesc *jd;
+
+	/*  Unfreeze the filesystem, if we need to  */
+
+	mutex_lock(&sdp->sd_freeze_lock);
+	if (sdp->sd_freeze_count)
+		gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
+	mutex_unlock(&sdp->sd_freeze_lock);
+
+	/* No more recovery requests */
+	set_bit(SDF_NORECOVERY, &sdp->sd_flags);
+	smp_mb();
+
+	/* Wait on outstanding recovery */
+restart:
+	spin_lock(&sdp->sd_jindex_spin);
+	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+		if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
+			continue;
+		spin_unlock(&sdp->sd_jindex_spin);
+		wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
+			    gfs2_umount_recovery_wait, TASK_UNINTERRUPTIBLE);
+		goto restart;
+	}
+	spin_unlock(&sdp->sd_jindex_spin);
+
+	kthread_stop(sdp->sd_quotad_process);
+	kthread_stop(sdp->sd_logd_process);
+
+	if (!(sb->s_flags & MS_RDONLY)) {
+		error = gfs2_make_fs_ro(sdp);
+		if (error)
+			gfs2_io_error(sdp);
+	}
+	/*  At this point, we're through modifying the disk  */
+
+	/*  Release stuff  */
+
+	iput(sdp->sd_jindex);
+	iput(sdp->sd_statfs_inode);
+	iput(sdp->sd_rindex);
+	iput(sdp->sd_quota_inode);
+
+	gfs2_glock_put(sdp->sd_rename_gl);
+	gfs2_glock_put(sdp->sd_trans_gl);
+
+	if (!sdp->sd_args.ar_spectator) {
+		gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
+		gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
+		gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
+		gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
+		iput(sdp->sd_sc_inode);
+		iput(sdp->sd_qc_inode);
+	}
+
+	gfs2_glock_dq_uninit(&sdp->sd_live_gh);
+	gfs2_clear_rgrpd(sdp);
+	gfs2_jindex_free(sdp);
+	/*  Take apart glock structures and buffer lists  */
+	gfs2_gl_hash_clear(sdp);
+	/*  Unmount the locking protocol  */
+	gfs2_lm_unmount(sdp);
+
+	/*  At this point, we're through participating in the lockspace  */
+	gfs2_sys_fs_del(sdp);
+}
+
+/**
+ * gfs2_sync_fs - sync the filesystem
+ * @sb: the superblock
+ *
+ * Flushes the log to disk.
+ */
+
+static int gfs2_sync_fs(struct super_block *sb, int wait)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	if (wait && sdp)
+		gfs2_log_flush(sdp, NULL);
+	return 0;
+}
+
+/**
+ * gfs2_freeze - prevent further writes to the filesystem
+ * @sb: the VFS structure for the filesystem
+ *
+ */
+
+static int gfs2_freeze(struct super_block *sb)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	int error;
+
+	if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
+		return -EINVAL;
+
+	for (;;) {
+		error = gfs2_freeze_fs(sdp);
+		if (!error)
+			break;
+
+		switch (error) {
+		case -EBUSY:
+			fs_err(sdp, "waiting for recovery before freeze\n");
+			break;
+
+		default:
+			fs_err(sdp, "error freezing FS: %d\n", error);
+			break;
+		}
+
+		fs_err(sdp, "retrying...\n");
+		msleep(1000);
+	}
+	return 0;
+}
+
+/**
+ * gfs2_unfreeze - reallow writes to the filesystem
+ * @sb: the VFS structure for the filesystem
+ *
+ */
+
+static int gfs2_unfreeze(struct super_block *sb)
+{
+	gfs2_unfreeze_fs(sb->s_fs_info);
+	return 0;
+}
+
+/**
+ * statfs_fill - fill in the sg for a given RG
+ * @rgd: the RG
+ * @sc: the sc structure
+ *
+ * Returns: 0 on success, -ESTALE if the LVB is invalid
+ */
+
+static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
+			    struct gfs2_statfs_change_host *sc)
+{
+	gfs2_rgrp_verify(rgd);
+	sc->sc_total += rgd->rd_data;
+	sc->sc_free += rgd->rd_free;
+	sc->sc_dinodes += rgd->rd_dinodes;
+	return 0;
+}
+
+/**
+ * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
+ * @sdp: the filesystem
+ * @sc: the sc info that will be returned
+ *
+ * Any error (other than a signal) will cause this routine to fall back
+ * to the synchronous version.
+ *
+ * FIXME: This really shouldn't busy wait like this.
+ *
+ * Returns: errno
+ */
+
+static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
+{
+	struct gfs2_rgrpd *rgd_next;
+	struct gfs2_holder *gha, *gh;
+	unsigned int slots = 64;
+	unsigned int x;
+	int done;
+	int error = 0, err;
+
+	memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
+	gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
+	if (!gha)
+		return -ENOMEM;
+
+	rgd_next = gfs2_rgrpd_get_first(sdp);
+
+	for (;;) {
+		done = 1;
+
+		for (x = 0; x < slots; x++) {
+			gh = gha + x;
+
+			if (gh->gh_gl && gfs2_glock_poll(gh)) {
+				err = gfs2_glock_wait(gh);
+				if (err) {
+					gfs2_holder_uninit(gh);
+					error = err;
+				} else {
+					if (!error)
+						error = statfs_slow_fill(
+							gh->gh_gl->gl_object, sc);
+					gfs2_glock_dq_uninit(gh);
+				}
+			}
+
+			if (gh->gh_gl)
+				done = 0;
+			else if (rgd_next && !error) {
+				error = gfs2_glock_nq_init(rgd_next->rd_gl,
+							   LM_ST_SHARED,
+							   GL_ASYNC,
+							   gh);
+				rgd_next = gfs2_rgrpd_get_next(rgd_next);
+				done = 0;
+			}
+
+			if (signal_pending(current))
+				error = -ERESTARTSYS;
+		}
+
+		if (done)
+			break;
+
+		yield();
+	}
+
+	kfree(gha);
+	return error;
+}
+
+/**
+ * gfs2_statfs_i - Do a statfs
+ * @sdp: the filesystem
+ * @sg: the sg structure
+ *
+ * Returns: errno
+ */
+
+static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
+{
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+
+	spin_lock(&sdp->sd_statfs_spin);
+
+	*sc = *m_sc;
+	sc->sc_total += l_sc->sc_total;
+	sc->sc_free += l_sc->sc_free;
+	sc->sc_dinodes += l_sc->sc_dinodes;
+
+	spin_unlock(&sdp->sd_statfs_spin);
+
+	if (sc->sc_free < 0)
+		sc->sc_free = 0;
+	if (sc->sc_free > sc->sc_total)
+		sc->sc_free = sc->sc_total;
+	if (sc->sc_dinodes < 0)
+		sc->sc_dinodes = 0;
+
+	return 0;
+}
+
+/**
+ * gfs2_statfs - Gather and return stats about the filesystem
+ * @sb: The superblock
+ * @statfsbuf: The buffer
+ *
+ * Returns: 0 on success or error code
+ */
+
+static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct super_block *sb = dentry->d_inode->i_sb;
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_statfs_change_host sc;
+	int error;
+
+	error = gfs2_rindex_update(sdp);
+	if (error)
+		return error;
+
+	if (gfs2_tune_get(sdp, gt_statfs_slow))
+		error = gfs2_statfs_slow(sdp, &sc);
+	else
+		error = gfs2_statfs_i(sdp, &sc);
+
+	if (error)
+		return error;
+
+	buf->f_type = GFS2_MAGIC;
+	buf->f_bsize = sdp->sd_sb.sb_bsize;
+	buf->f_blocks = sc.sc_total;
+	buf->f_bfree = sc.sc_free;
+	buf->f_bavail = sc.sc_free;
+	buf->f_files = sc.sc_dinodes + sc.sc_free;
+	buf->f_ffree = sc.sc_free;
+	buf->f_namelen = GFS2_FNAMESIZE;
+
+	return 0;
+}
+
+/**
+ * gfs2_remount_fs - called when the FS is remounted
+ * @sb:  the filesystem
+ * @flags:  the remount flags
+ * @data:  extra data passed in (not used right now)
+ *
+ * Returns: errno
+ */
+
+static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_args args = sdp->sd_args; /* Default to current settings */
+	struct gfs2_tune *gt = &sdp->sd_tune;
+	int error;
+
+	spin_lock(&gt->gt_spin);
+	args.ar_commit = gt->gt_logd_secs;
+	args.ar_quota_quantum = gt->gt_quota_quantum;
+	if (gt->gt_statfs_slow)
+		args.ar_statfs_quantum = 0;
+	else
+		args.ar_statfs_quantum = gt->gt_statfs_quantum;
+	spin_unlock(&gt->gt_spin);
+	error = gfs2_mount_args(&args, data);
+	if (error)
+		return error;
+
+	/* Not allowed to change locking details */
+	if (strcmp(args.ar_lockproto, sdp->sd_args.ar_lockproto) ||
+	    strcmp(args.ar_locktable, sdp->sd_args.ar_locktable) ||
+	    strcmp(args.ar_hostdata, sdp->sd_args.ar_hostdata))
+		return -EINVAL;
+
+	/* Some flags must not be changed */
+	if (args_neq(&args, &sdp->sd_args, spectator) ||
+	    args_neq(&args, &sdp->sd_args, localflocks) ||
+	    args_neq(&args, &sdp->sd_args, meta))
+		return -EINVAL;
+
+	if (sdp->sd_args.ar_spectator)
+		*flags |= MS_RDONLY;
+
+	if ((sb->s_flags ^ *flags) & MS_RDONLY) {
+		if (*flags & MS_RDONLY)
+			error = gfs2_make_fs_ro(sdp);
+		else
+			error = gfs2_make_fs_rw(sdp);
+		if (error)
+			return error;
+	}
+
+	sdp->sd_args = args;
+	if (sdp->sd_args.ar_posix_acl)
+		sb->s_flags |= MS_POSIXACL;
+	else
+		sb->s_flags &= ~MS_POSIXACL;
+	if (sdp->sd_args.ar_nobarrier)
+		set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
+	else
+		clear_bit(SDF_NOBARRIERS, &sdp->sd_flags);
+	spin_lock(&gt->gt_spin);
+	gt->gt_logd_secs = args.ar_commit;
+	gt->gt_quota_quantum = args.ar_quota_quantum;
+	if (args.ar_statfs_quantum) {
+		gt->gt_statfs_slow = 0;
+		gt->gt_statfs_quantum = args.ar_statfs_quantum;
+	}
+	else {
+		gt->gt_statfs_slow = 1;
+		gt->gt_statfs_quantum = 30;
+	}
+	spin_unlock(&gt->gt_spin);
+
+	gfs2_online_uevent(sdp);
+	return 0;
+}
+
+/**
+ * gfs2_drop_inode - Drop an inode (test for remote unlink)
+ * @inode: The inode to drop
+ *
+ * If we've received a callback on an iopen lock then its because a
+ * remote node tried to deallocate the inode but failed due to this node
+ * still having the inode open. Here we mark the link count zero
+ * since we know that it must have reached zero if the GLF_DEMOTE flag
+ * is set on the iopen glock. If we didn't do a disk read since the
+ * remote node removed the final link then we might otherwise miss
+ * this event. This check ensures that this node will deallocate the
+ * inode's blocks, or alternatively pass the baton on to another
+ * node for later deallocation.
+ */
+
+static int gfs2_drop_inode(struct inode *inode)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+
+	if (inode->i_nlink) {
+		struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
+		if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
+			clear_nlink(inode);
+	}
+	return generic_drop_inode(inode);
+}
+
+static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
+{
+	do {
+		if (d1 == d2)
+			return 1;
+		d1 = d1->d_parent;
+	} while (!IS_ROOT(d1));
+	return 0;
+}
+
+/**
+ * gfs2_show_options - Show mount options for /proc/mounts
+ * @s: seq_file structure
+ * @root: root of this (sub)tree
+ *
+ * Returns: 0 on success or error code
+ */
+
+static int gfs2_show_options(struct seq_file *s, struct dentry *root)
+{
+	struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
+	struct gfs2_args *args = &sdp->sd_args;
+	int val;
+
+	if (is_ancestor(root, sdp->sd_master_dir))
+		seq_printf(s, ",meta");
+	if (args->ar_lockproto[0])
+		seq_printf(s, ",lockproto=%s", args->ar_lockproto);
+	if (args->ar_locktable[0])
+		seq_printf(s, ",locktable=%s", args->ar_locktable);
+	if (args->ar_hostdata[0])
+		seq_printf(s, ",hostdata=%s", args->ar_hostdata);
+	if (args->ar_spectator)
+		seq_printf(s, ",spectator");
+	if (args->ar_localflocks)
+		seq_printf(s, ",localflocks");
+	if (args->ar_debug)
+		seq_printf(s, ",debug");
+	if (args->ar_posix_acl)
+		seq_printf(s, ",acl");
+	if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
+		char *state;
+		switch (args->ar_quota) {
+		case GFS2_QUOTA_OFF:
+			state = "off";
+			break;
+		case GFS2_QUOTA_ACCOUNT:
+			state = "account";
+			break;
+		case GFS2_QUOTA_ON:
+			state = "on";
+			break;
+		default:
+			state = "unknown";
+			break;
+		}
+		seq_printf(s, ",quota=%s", state);
+	}
+	if (args->ar_suiddir)
+		seq_printf(s, ",suiddir");
+	if (args->ar_data != GFS2_DATA_DEFAULT) {
+		char *state;
+		switch (args->ar_data) {
+		case GFS2_DATA_WRITEBACK:
+			state = "writeback";
+			break;
+		case GFS2_DATA_ORDERED:
+			state = "ordered";
+			break;
+		default:
+			state = "unknown";
+			break;
+		}
+		seq_printf(s, ",data=%s", state);
+	}
+	if (args->ar_discard)
+		seq_printf(s, ",discard");
+	val = sdp->sd_tune.gt_logd_secs;
+	if (val != 30)
+		seq_printf(s, ",commit=%d", val);
+	val = sdp->sd_tune.gt_statfs_quantum;
+	if (val != 30)
+		seq_printf(s, ",statfs_quantum=%d", val);
+	val = sdp->sd_tune.gt_quota_quantum;
+	if (val != 60)
+		seq_printf(s, ",quota_quantum=%d", val);
+	if (args->ar_statfs_percent)
+		seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
+	if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
+		const char *state;
+
+		switch (args->ar_errors) {
+		case GFS2_ERRORS_WITHDRAW:
+			state = "withdraw";
+			break;
+		case GFS2_ERRORS_PANIC:
+			state = "panic";
+			break;
+		default:
+			state = "unknown";
+			break;
+		}
+		seq_printf(s, ",errors=%s", state);
+	}
+	if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
+		seq_printf(s, ",nobarrier");
+	if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
+		seq_printf(s, ",demote_interface_used");
+	return 0;
+}
+
+static void gfs2_final_release_pages(struct gfs2_inode *ip)
+{
+	struct inode *inode = &ip->i_inode;
+	struct gfs2_glock *gl = ip->i_gl;
+
+	truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
+	truncate_inode_pages(&inode->i_data, 0);
+
+	if (atomic_read(&gl->gl_revokes) == 0) {
+		clear_bit(GLF_LFLUSH, &gl->gl_flags);
+		clear_bit(GLF_DIRTY, &gl->gl_flags);
+	}
+}
+
+static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
+{
+	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+	struct gfs2_qadata *qa;
+	struct gfs2_rgrpd *rgd;
+	struct gfs2_holder gh;
+	int error;
+
+	if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
+		gfs2_consist_inode(ip);
+		return -EIO;
+	}
+
+	qa = gfs2_qadata_get(ip);
+	if (!qa)
+		return -ENOMEM;
+
+	error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
+	if (error)
+		goto out;
+
+	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
+	if (!rgd) {
+		gfs2_consist_inode(ip);
+		error = -EIO;
+		goto out_qs;
+	}
+
+	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
+	if (error)
+		goto out_qs;
+
+	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
+				 sdp->sd_jdesc->jd_blocks);
+	if (error)
+		goto out_rg_gunlock;
+
+	gfs2_free_di(rgd, ip);
+
+	gfs2_final_release_pages(ip);
+
+	gfs2_trans_end(sdp);
+
+out_rg_gunlock:
+	gfs2_glock_dq_uninit(&gh);
+out_qs:
+	gfs2_quota_unhold(ip);
+out:
+	gfs2_qadata_put(ip);
+	return error;
+}
+
+/**
+ * gfs2_evict_inode - Remove an inode from cache
+ * @inode: The inode to evict
+ *
+ * There are three cases to consider:
+ * 1. i_nlink == 0, we are final opener (and must deallocate)
+ * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
+ * 3. i_nlink > 0
+ *
+ * If the fs is read only, then we have to treat all cases as per #3
+ * since we are unable to do any deallocation. The inode will be
+ * deallocated by the next read/write node to attempt an allocation
+ * in the same resource group
+ *
+ * We have to (at the moment) hold the inodes main lock to cover
+ * the gap between unlocking the shared lock on the iopen lock and
+ * taking the exclusive lock. I'd rather do a shared -> exclusive
+ * conversion on the iopen lock, but we can change that later. This
+ * is safe, just less efficient.
+ */
+
+static void gfs2_evict_inode(struct inode *inode)
+{
+	struct super_block *sb = inode->i_sb;
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_holder gh;
+	int error;
+
+	if (inode->i_nlink || (sb->s_flags & MS_RDONLY))
+		goto out;
+
+	/* Must not read inode block until block type has been verified */
+	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
+	if (unlikely(error)) {
+		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
+		goto out;
+	}
+
+	if (!test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
+		error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
+		if (error)
+			goto out_truncate;
+	}
+
+	if (test_bit(GIF_INVALID, &ip->i_flags)) {
+		error = gfs2_inode_refresh(ip);
+		if (error)
+			goto out_truncate;
+	}
+
+	ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
+	gfs2_glock_dq_wait(&ip->i_iopen_gh);
+	gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
+	error = gfs2_glock_nq(&ip->i_iopen_gh);
+	if (error)
+		goto out_truncate;
+
+	/* Case 1 starts here */
+
+	if (S_ISDIR(inode->i_mode) &&
+	    (ip->i_diskflags & GFS2_DIF_EXHASH)) {
+		error = gfs2_dir_exhash_dealloc(ip);
+		if (error)
+			goto out_unlock;
+	}
+
+	if (ip->i_eattr) {
+		error = gfs2_ea_dealloc(ip);
+		if (error)
+			goto out_unlock;
+	}
+
+	if (!gfs2_is_stuffed(ip)) {
+		error = gfs2_file_dealloc(ip);
+		if (error)
+			goto out_unlock;
+	}
+
+	error = gfs2_dinode_dealloc(ip);
+	goto out_unlock;
+
+out_truncate:
+	gfs2_log_flush(sdp, ip->i_gl);
+	write_inode_now(inode, 1);
+	gfs2_ail_flush(ip->i_gl, 0);
+
+	/* Case 2 starts here */
+	error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
+	if (error)
+		goto out_unlock;
+	/* Needs to be done before glock release & also in a transaction */
+	truncate_inode_pages(&inode->i_data, 0);
+	gfs2_trans_end(sdp);
+
+out_unlock:
+	/* Error path for case 1 */
+	if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags))
+		gfs2_glock_dq(&ip->i_iopen_gh);
+	gfs2_holder_uninit(&ip->i_iopen_gh);
+	gfs2_glock_dq_uninit(&gh);
+	if (error && error != GLR_TRYFAILED && error != -EROFS)
+		fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
+out:
+	/* Case 3 starts here */
+	truncate_inode_pages(&inode->i_data, 0);
+	end_writeback(inode);
+	gfs2_dir_hash_inval(ip);
+	ip->i_gl->gl_object = NULL;
+	flush_delayed_work_sync(&ip->i_gl->gl_work);
+	gfs2_glock_add_to_lru(ip->i_gl);
+	gfs2_glock_put(ip->i_gl);
+	ip->i_gl = NULL;
+	if (ip->i_iopen_gh.gh_gl) {
+		ip->i_iopen_gh.gh_gl->gl_object = NULL;
+		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
+	}
+}
+
+static struct inode *gfs2_alloc_inode(struct super_block *sb)
+{
+	struct gfs2_inode *ip;
+
+	ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
+	if (ip) {
+		ip->i_flags = 0;
+		ip->i_gl = NULL;
+		ip->i_rgd = NULL;
+	}
+	return &ip->i_inode;
+}
+
+static void gfs2_i_callback(struct rcu_head *head)
+{
+	struct inode *inode = container_of(head, struct inode, i_rcu);
+	kmem_cache_free(gfs2_inode_cachep, inode);
+}
+
+static void gfs2_destroy_inode(struct inode *inode)
+{
+	call_rcu(&inode->i_rcu, gfs2_i_callback);
+}
+
+const struct super_operations gfs2_super_ops = {
+	.alloc_inode		= gfs2_alloc_inode,
+	.destroy_inode		= gfs2_destroy_inode,
+	.write_inode		= gfs2_write_inode,
+	.dirty_inode		= gfs2_dirty_inode,
+	.evict_inode		= gfs2_evict_inode,
+	.put_super		= gfs2_put_super,
+	.sync_fs		= gfs2_sync_fs,
+	.freeze_fs 		= gfs2_freeze,
+	.unfreeze_fs		= gfs2_unfreeze,
+	.statfs			= gfs2_statfs,
+	.remount_fs		= gfs2_remount_fs,
+	.drop_inode		= gfs2_drop_inode,
+	.show_options		= gfs2_show_options,
+};
+