// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2008 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/blkdev.h>
#include <linux/kthread.h>
#include <linux/export.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/gfs2_ondisk.h>
#include <linux/quotaops.h>
#include <linux/lockdep.h>
#include <linux/module.h>
#include <linux/backing-dev.h>
#include <linux/fs_parser.h>

#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "recovery.h"
#include "rgrp.h"
#include "super.h"
#include "sys.h"
#include "util.h"
#include "log.h"
#include "quota.h"
#include "dir.h"
#include "meta_io.h"
#include "trace_gfs2.h"
#include "lops.h"

#define DO 0
#define UNDO 1

/**
 * gfs2_tune_init - Fill a gfs2_tune structure with default values
 * @gt: tune
 *
 */

static void gfs2_tune_init(struct gfs2_tune *gt)
{
        spin_lock_init(&gt->gt_spin);

        gt->gt_quota_warn_period = 10;
        gt->gt_quota_scale_num = 1;
        gt->gt_quota_scale_den = 1;
        gt->gt_new_files_jdata = 0;
        gt->gt_max_readahead = BIT(18);
        gt->gt_complain_secs = 10;
        gt->gt_withdraw_helper_timeout = 5;
}

void free_sbd(struct gfs2_sbd *sdp)
{
        struct super_block *sb = sdp->sd_vfs;

        free_percpu(sdp->sd_lkstats);
        sb->s_fs_info = NULL;
        kfree(sdp);
}

static struct gfs2_sbd *init_sbd(struct super_block *sb)
{
        struct gfs2_sbd *sdp;

        sdp = kzalloc_obj(struct gfs2_sbd);
        if (!sdp)
                return NULL;

        sdp->sd_vfs = sb;
        sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
        if (!sdp->sd_lkstats)
                goto fail;
        sb->s_fs_info = sdp;

        set_bit(SDF_NOJOURNALID, &sdp->sd_flags);
        gfs2_tune_init(&sdp->sd_tune);

        init_waitqueue_head(&sdp->sd_kill_wait);
        init_waitqueue_head(&sdp->sd_async_glock_wait);
        atomic_set(&sdp->sd_glock_disposal, 0);
        init_completion(&sdp->sd_locking_init);
        init_completion(&sdp->sd_withdraw_helper);
        spin_lock_init(&sdp->sd_statfs_spin);

        spin_lock_init(&sdp->sd_rindex_spin);
        sdp->sd_rindex_tree.rb_node = NULL;

        INIT_LIST_HEAD(&sdp->sd_jindex_list);
        spin_lock_init(&sdp->sd_jindex_spin);
        mutex_init(&sdp->sd_jindex_mutex);
        init_completion(&sdp->sd_journal_ready);

        INIT_LIST_HEAD(&sdp->sd_quota_list);
        mutex_init(&sdp->sd_quota_sync_mutex);
        init_waitqueue_head(&sdp->sd_quota_wait);
        spin_lock_init(&sdp->sd_bitmap_lock);

        INIT_LIST_HEAD(&sdp->sd_sc_inodes_list);

        spin_lock_init(&sdp->sd_log_lock);
        atomic_set(&sdp->sd_log_pinned, 0);
        INIT_LIST_HEAD(&sdp->sd_log_revokes);
        INIT_LIST_HEAD(&sdp->sd_log_ordered);
        spin_lock_init(&sdp->sd_ordered_lock);

        init_waitqueue_head(&sdp->sd_log_waitq);
        init_waitqueue_head(&sdp->sd_logd_waitq);
        spin_lock_init(&sdp->sd_ail_lock);
        INIT_LIST_HEAD(&sdp->sd_ail1_list);
        INIT_LIST_HEAD(&sdp->sd_ail2_list);

        init_rwsem(&sdp->sd_log_flush_lock);
        atomic_set(&sdp->sd_log_in_flight, 0);
        init_waitqueue_head(&sdp->sd_log_flush_wait);
        mutex_init(&sdp->sd_freeze_mutex);
        INIT_LIST_HEAD(&sdp->sd_dead_glocks);

        return sdp;

fail:
        free_sbd(sdp);
        return NULL;
}

/**
 * gfs2_check_sb - Check superblock
 * @sdp: the filesystem
 * @silent: Don't print a message if the check fails
 *
 * Checks the version code of the FS is one that we understand how to
 * read and that the sizes of the various on-disk structures have not
 * changed.
 */

static int gfs2_check_sb(struct gfs2_sbd *sdp, int silent)
{
        struct gfs2_sb_host *sb = &sdp->sd_sb;

        if (sb->sb_magic != GFS2_MAGIC ||
            sb->sb_type != GFS2_METATYPE_SB) {
                if (!silent)
                        pr_warn("not a GFS2 filesystem\n");
                return -EINVAL;
        }

        if (sb->sb_fs_format < GFS2_FS_FORMAT_MIN ||
            sb->sb_fs_format > GFS2_FS_FORMAT_MAX ||
            sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
                fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
                return -EINVAL;
        }

        if (sb->sb_bsize < SECTOR_SIZE || sb->sb_bsize > PAGE_SIZE ||
            (sb->sb_bsize & (sb->sb_bsize - 1))) {
                pr_warn("Invalid block size\n");
                return -EINVAL;
        }
        if (sb->sb_bsize_shift != ffs(sb->sb_bsize) - 1) {
                pr_warn("Invalid block size shift\n");
                return -EINVAL;
        }
        return 0;
}

static void gfs2_sb_in(struct gfs2_sbd *sdp, const struct gfs2_sb *str)
{
        struct gfs2_sb_host *sb = &sdp->sd_sb;
        struct super_block *s = sdp->sd_vfs;

        sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
        sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
        sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
        sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
        sb->sb_bsize = be32_to_cpu(str->sb_bsize);
        sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
        sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
        sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
        sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
        sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);

        memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
        memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
        super_set_uuid(s, str->sb_uuid, 16);
}

/**
 * gfs2_read_super - Read the gfs2 super block from disk
 * @sdp: The GFS2 super block
 * @sector: The location of the super block
 * @silent: Don't print a message if the check fails
 *
 * This uses the bio functions to read the super block from disk
 * because we want to be 100% sure that we never read cached data.
 * A super block is read twice only during each GFS2 mount and is
 * never written to by the filesystem. The first time its read no
 * locks are held, and the only details which are looked at are those
 * relating to the locking protocol. Once locking is up and working,
 * the sb is read again under the lock to establish the location of
 * the master directory (contains pointers to journals etc) and the
 * root directory.
 *
 * Returns: 0 on success or error
 */

static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
{
        struct gfs2_sb *sb;
        int err;

        sb = kmalloc(PAGE_SIZE, GFP_KERNEL);
        if (unlikely(!sb))
                return -ENOMEM;
        err = bdev_rw_virt(sdp->sd_vfs->s_bdev,
                           sector << (sdp->sd_vfs->s_blocksize_bits - SECTOR_SHIFT),
                           sb, PAGE_SIZE, REQ_OP_READ | REQ_META);
        if (err) {
                pr_warn("error %d reading superblock\n", err);
                kfree(sb);
                return err;
        }
        gfs2_sb_in(sdp, sb);
        kfree(sb);
        return gfs2_check_sb(sdp, silent);
}

/**
 * gfs2_read_sb - Read super block
 * @sdp: The GFS2 superblock
 * @silent: Don't print message if mount fails
 *
 */

static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
{
        u32 hash_blocks, ind_blocks, leaf_blocks;
        u32 tmp_blocks;
        unsigned int x;
        int error;

        error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
        if (error) {
                if (!silent)
                        fs_err(sdp, "can't read superblock\n");
                return error;
        }

        sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift - SECTOR_SHIFT;
        sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
        sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
                          sizeof(struct gfs2_dinode)) / sizeof(u64);
        sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
                          sizeof(struct gfs2_meta_header)) / sizeof(u64);
        sdp->sd_ldptrs = (sdp->sd_sb.sb_bsize -
                          sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
        sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
        sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
        sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
        sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
        sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
                                sizeof(struct gfs2_meta_header)) /
                                sizeof(struct gfs2_quota_change);
        sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize -
                                     sizeof(struct gfs2_meta_header))
                * GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */

        /*
         * We always keep at least one block reserved for revokes in
         * transactions.  This greatly simplifies allocating additional
         * revoke blocks.
         */
        atomic_set(&sdp->sd_log_revokes_available, sdp->sd_ldptrs);

        /* Compute maximum reservation required to add a entry to a directory */

        hash_blocks = DIV_ROUND_UP(sizeof(u64) * BIT(GFS2_DIR_MAX_DEPTH),
                             sdp->sd_jbsize);

        ind_blocks = 0;
        for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
                tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
                ind_blocks += tmp_blocks;
        }

        leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;

        sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;

        sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
                                sizeof(struct gfs2_dinode);
        sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
        for (x = 2;; x++) {
                u64 space, d;
                u32 m;

                space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
                d = space;
                m = do_div(d, sdp->sd_inptrs);

                if (d != sdp->sd_heightsize[x - 1] || m)
                        break;
                sdp->sd_heightsize[x] = space;
        }
        sdp->sd_max_height = x;
        sdp->sd_heightsize[x] = ~0;
        gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);

        sdp->sd_max_dents_per_leaf = (sdp->sd_sb.sb_bsize -
                                      sizeof(struct gfs2_leaf)) /
                                     GFS2_MIN_DIRENT_SIZE;
        return 0;
}

static int init_names(struct gfs2_sbd *sdp, int silent)
{
        char *proto, *table;
        int error = 0;

        proto = sdp->sd_args.ar_lockproto;
        table = sdp->sd_args.ar_locktable;

        /*  Try to autodetect  */

        if (!proto[0] || !table[0]) {
                error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
                if (error)
                        return error;

                if (!proto[0])
                        proto = sdp->sd_sb.sb_lockproto;
                if (!table[0])
                        table = sdp->sd_sb.sb_locktable;
        }

        if (!table[0])
                table = sdp->sd_vfs->s_id;

        BUILD_BUG_ON(GFS2_LOCKNAME_LEN > GFS2_FSNAME_LEN);

        strscpy(sdp->sd_proto_name, proto, GFS2_LOCKNAME_LEN);
        strscpy(sdp->sd_table_name, table, GFS2_LOCKNAME_LEN);

        table = sdp->sd_table_name;
        while ((table = strchr(table, '/')))
                *table = '_';

        return error;
}

static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
                        int undo)
{
        int error = 0;

        if (undo)
                goto fail_trans;

        error = gfs2_glock_nq_num(sdp,
                                  GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
                                  LM_ST_EXCLUSIVE,
                                  LM_FLAG_RECOVER | GL_NOCACHE | GL_NOPID,
                                  mount_gh);
        if (error) {
                fs_err(sdp, "can't acquire mount glock: %d\n", error);
                goto fail;
        }

        error = gfs2_glock_nq_num(sdp,
                                  GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
                                  LM_ST_SHARED,
                                  LM_FLAG_RECOVER | GL_EXACT | GL_NOPID,
                                  &sdp->sd_live_gh);
        if (error) {
                fs_err(sdp, "can't acquire live glock: %d\n", error);
                goto fail_mount;
        }

        error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
                               CREATE, &sdp->sd_rename_gl);
        if (error) {
                fs_err(sdp, "can't create rename glock: %d\n", error);
                goto fail_live;
        }

        error = gfs2_glock_get(sdp, GFS2_FREEZE_LOCK, &gfs2_freeze_glops,
                               CREATE, &sdp->sd_freeze_gl);
        if (error) {
                fs_err(sdp, "can't create freeze glock: %d\n", error);
                goto fail_rename;
        }

        return 0;

fail_trans:
        gfs2_glock_put(sdp->sd_freeze_gl);
fail_rename:
        gfs2_glock_put(sdp->sd_rename_gl);
fail_live:
        gfs2_glock_dq_uninit(&sdp->sd_live_gh);
fail_mount:
        gfs2_glock_dq_uninit(mount_gh);
fail:
        return error;
}

static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
                            u64 no_addr, const char *name)
{
        struct gfs2_sbd *sdp = sb->s_fs_info;
        struct dentry *dentry;
        struct inode *inode;

        inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0,
                                  GFS2_BLKST_FREE /* ignore */);
        if (IS_ERR(inode)) {
                fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
                return PTR_ERR(inode);
        }
        dentry = d_make_root(inode);
        if (!dentry) {
                fs_err(sdp, "can't alloc %s dentry\n", name);
                return -ENOMEM;
        }
        *dptr = dentry;
        return 0;
}

static int init_sb(struct gfs2_sbd *sdp, int silent)
{
        struct super_block *sb = sdp->sd_vfs;
        struct gfs2_holder sb_gh;
        u64 no_addr;
        int ret;

        ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
                                LM_ST_SHARED, 0, &sb_gh);
        if (ret) {
                fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
                return ret;
        }

        ret = gfs2_read_sb(sdp, silent);
        if (ret) {
                fs_err(sdp, "can't read superblock: %d\n", ret);
                goto out;
        }

        switch(sdp->sd_sb.sb_fs_format) {
        case GFS2_FS_FORMAT_MAX:
                sb->s_xattr = gfs2_xattr_handlers_max;
                break;

        case GFS2_FS_FORMAT_MIN:
                sb->s_xattr = gfs2_xattr_handlers_min;
                break;

        default:
                BUG();
        }

        /* Set up the buffer cache and SB for real */
        if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
                ret = -EINVAL;
                fs_err(sdp, "FS block size (%u) is too small for device "
                       "block size (%u)\n",
                       sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
                goto out;
        }
        if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
                ret = -EINVAL;
                fs_err(sdp, "FS block size (%u) is too big for machine "
                       "page size (%u)\n",
                       sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
                goto out;
        }
        ret = -EINVAL;
        if (!sb_set_blocksize(sb, sdp->sd_sb.sb_bsize))
                goto out;

        /* Get the root inode */
        no_addr = sdp->sd_sb.sb_root_dir.no_addr;
        ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
        if (ret)
                goto out;

        /* Get the master inode */
        no_addr = sdp->sd_sb.sb_master_dir.no_addr;
        ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
        if (ret) {
                dput(sdp->sd_root_dir);
                goto out;
        }
        sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
out:
        gfs2_glock_dq_uninit(&sb_gh);
        return ret;
}

static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
{
        char *message = "FIRSTMOUNT=Done";
        char *envp[] = { message, NULL };

        fs_info(sdp, "first mount done, others may mount\n");

        if (sdp->sd_lockstruct.ls_ops->lm_first_done)
                sdp->sd_lockstruct.ls_ops->lm_first_done(sdp);

        kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
}

/**
 * gfs2_jindex_hold - Grab a lock on the jindex
 * @sdp: The GFS2 superblock
 * @ji_gh: the holder for the jindex glock
 *
 * Returns: errno
 */

static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
{
        struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
        struct qstr name;
        char buf[20];
        struct gfs2_jdesc *jd;
        int error;

        name.name = buf;

        mutex_lock(&sdp->sd_jindex_mutex);

        for (;;) {
                error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
                if (error)
                        break;

                name.len = sprintf(buf, "journal%u", sdp->sd_journals);
                name.hash = gfs2_disk_hash(name.name, name.len);

                error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
                if (error == -ENOENT) {
                        error = 0;
                        break;
                }

                gfs2_glock_dq_uninit(ji_gh);

                if (error)
                        break;

                error = -ENOMEM;
                jd = kzalloc_obj(struct gfs2_jdesc);
                if (!jd)
                        break;

                INIT_LIST_HEAD(&jd->extent_list);
                INIT_LIST_HEAD(&jd->jd_revoke_list);

                INIT_WORK(&jd->jd_work, gfs2_recover_func);
                jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
                if (IS_ERR_OR_NULL(jd->jd_inode)) {
                        if (!jd->jd_inode)
                                error = -ENOENT;
                        else
                                error = PTR_ERR(jd->jd_inode);
                        kfree(jd);
                        break;
                }

                d_mark_dontcache(jd->jd_inode);
                spin_lock(&sdp->sd_jindex_spin);
                jd->jd_jid = sdp->sd_journals++;
                list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
                spin_unlock(&sdp->sd_jindex_spin);
        }

        mutex_unlock(&sdp->sd_jindex_mutex);

        return error;
}

/**
 * init_statfs - look up and initialize master and local (per node) statfs inodes
 * @sdp: The GFS2 superblock
 *
 * This should be called after the jindex is initialized in init_journal() and
 * before gfs2_journal_recovery() is called because we need to be able to write
 * to these inodes during recovery.
 *
 * Returns: errno
 */
static int init_statfs(struct gfs2_sbd *sdp)
{
        int error = 0;
        struct inode *master = d_inode(sdp->sd_master_dir);
        struct inode *pn = NULL;
        char buf[30];
        struct gfs2_jdesc *jd;
        struct gfs2_inode *ip;

        sdp->sd_statfs_inode = gfs2_lookup_meta(master, "statfs");
        if (IS_ERR(sdp->sd_statfs_inode)) {
                error = PTR_ERR(sdp->sd_statfs_inode);
                fs_err(sdp, "can't read in statfs inode: %d\n", error);
                goto out;
        }
        if (sdp->sd_args.ar_spectator)
                goto out;

        pn = gfs2_lookup_meta(master, "per_node");
        if (IS_ERR(pn)) {
                error = PTR_ERR(pn);
                fs_err(sdp, "can't find per_node directory: %d\n", error);
                goto put_statfs;
        }

        /* For each jid, lookup the corresponding local statfs inode in the
         * per_node metafs directory and save it in the sdp->sd_sc_inodes_list. */
        list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
                struct local_statfs_inode *lsi =
                        kmalloc_obj(struct local_statfs_inode, GFP_NOFS);
                if (!lsi) {
                        error = -ENOMEM;
                        goto free_local;
                }
                sprintf(buf, "statfs_change%u", jd->jd_jid);
                lsi->si_sc_inode = gfs2_lookup_meta(pn, buf);
                if (IS_ERR(lsi->si_sc_inode)) {
                        error = PTR_ERR(lsi->si_sc_inode);
                        fs_err(sdp, "can't find local \"sc\" file#%u: %d\n",
                               jd->jd_jid, error);
                        kfree(lsi);
                        goto free_local;
                }
                lsi->si_jid = jd->jd_jid;
                if (jd->jd_jid == sdp->sd_jdesc->jd_jid)
                        sdp->sd_sc_inode = lsi->si_sc_inode;

                list_add_tail(&lsi->si_list, &sdp->sd_sc_inodes_list);
        }

        iput(pn);
        pn = NULL;
        ip = GFS2_I(sdp->sd_sc_inode);
        error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_NOPID,
                                   &sdp->sd_sc_gh);
        if (error) {
                fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
                goto free_local;
        }
        /* read in the local statfs buffer - other nodes don't change it. */
        error = gfs2_meta_inode_buffer(ip, &sdp->sd_sc_bh);
        if (error) {
                fs_err(sdp, "Cannot read in local statfs: %d\n", error);
                goto unlock_sd_gh;
        }
        return 0;

unlock_sd_gh:
        gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
free_local:
        free_local_statfs_inodes(sdp);
        iput(pn);
put_statfs:
        iput(sdp->sd_statfs_inode);
out:
        return error;
}

/* Uninitialize and free up memory used by the list of statfs inodes */
static void uninit_statfs(struct gfs2_sbd *sdp)
{
        if (!sdp->sd_args.ar_spectator) {
                brelse(sdp->sd_sc_bh);
                gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
                free_local_statfs_inodes(sdp);
        }
        iput(sdp->sd_statfs_inode);
}

static int init_journal(struct gfs2_sbd *sdp, int undo)
{
        struct inode *master = d_inode(sdp->sd_master_dir);
        struct gfs2_holder ji_gh;
        struct gfs2_inode *ip;
        int error = 0;

        gfs2_holder_mark_uninitialized(&ji_gh);
        if (undo)
                goto fail_statfs;

        sdp->sd_jindex = gfs2_lookup_meta(master, "jindex");
        if (IS_ERR(sdp->sd_jindex)) {
                fs_err(sdp, "can't lookup journal index: %d\n", error);
                return PTR_ERR(sdp->sd_jindex);
        }

        /* Load in the journal index special file */

        error = gfs2_jindex_hold(sdp, &ji_gh);
        if (error) {
                fs_err(sdp, "can't read journal index: %d\n", error);
                goto fail;
        }

        error = -EUSERS;
        if (!gfs2_jindex_size(sdp)) {
                fs_err(sdp, "no journals!\n");
                goto fail_jindex;
        }

        atomic_set(&sdp->sd_log_blks_needed, 0);
        if (sdp->sd_args.ar_spectator) {
                sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
                atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
                atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
                atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
        } else {
                if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
                        fs_err(sdp, "can't mount journal #%u\n",
                               sdp->sd_lockstruct.ls_jid);
                        fs_err(sdp, "there are only %u journals (0 - %u)\n",
                               gfs2_jindex_size(sdp),
                               gfs2_jindex_size(sdp) - 1);
                        goto fail_jindex;
                }
                sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);

                error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
                                          &gfs2_journal_glops,
                                          LM_ST_EXCLUSIVE,
                                          LM_FLAG_RECOVER | GL_NOPID,
                                          &sdp->sd_journal_gh);
                if (error) {
                        fs_err(sdp, "can't acquire journal glock: %d\n", error);
                        goto fail_jindex;
                }

                ip = GFS2_I(sdp->sd_jdesc->jd_inode);
                error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
                                           LM_FLAG_RECOVER | GL_EXACT |
                                           GL_NOCACHE | GL_NOPID,
                                           &sdp->sd_jinode_gh);
                if (error) {
                        fs_err(sdp, "can't acquire journal inode glock: %d\n",
                               error);
                        goto fail_journal_gh;
                }

                error = gfs2_jdesc_check(sdp->sd_jdesc);
                if (error) {
                        fs_err(sdp, "my journal (%u) is bad: %d\n",
                               sdp->sd_jdesc->jd_jid, error);
                        goto fail_jinode_gh;
                }
                atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
                atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
                atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);

                /* Map the extents for this journal's blocks */
                gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
        }
        trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));

        /* Lookup statfs inodes here so journal recovery can use them. */
        error = init_statfs(sdp);
        if (error)
                goto fail_jinode_gh;

        if (sdp->sd_lockstruct.ls_first) {
                unsigned int x;
                for (x = 0; x < sdp->sd_journals; x++) {
                        struct gfs2_jdesc *jd = gfs2_jdesc_find(sdp, x);

                        if (sdp->sd_args.ar_spectator) {
                                error = check_journal_clean(sdp, jd, true);
                                if (error)
                                        goto fail_statfs;
                                continue;
                        }
                        error = gfs2_recover_journal(jd, true);
                        if (error) {
                                fs_err(sdp, "error recovering journal %u: %d\n",
                                       x, error);
                                goto fail_statfs;
                        }
                }

                gfs2_others_may_mount(sdp);
        } else if (!sdp->sd_args.ar_spectator) {
                error = gfs2_recover_journal(sdp->sd_jdesc, true);
                if (error) {
                        fs_err(sdp, "error recovering my journal: %d\n", error);
                        goto fail_statfs;
                }
        }

        sdp->sd_log_idle = 1;
        set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
        gfs2_glock_dq_uninit(&ji_gh);
        INIT_WORK(&sdp->sd_freeze_work, gfs2_freeze_func);
        return 0;

fail_statfs:
        uninit_statfs(sdp);
fail_jinode_gh:
        if (!sdp->sd_args.ar_spectator)
                gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
fail_journal_gh:
        if (!sdp->sd_args.ar_spectator)
                gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
fail_jindex:
        gfs2_jindex_free(sdp);
        if (gfs2_holder_initialized(&ji_gh))
                gfs2_glock_dq_uninit(&ji_gh);
fail:
        iput(sdp->sd_jindex);
        return error;
}

static struct lock_class_key gfs2_quota_imutex_key;

static int init_inodes(struct gfs2_sbd *sdp, int undo)
{
        int error = 0;
        struct inode *master = d_inode(sdp->sd_master_dir);

        if (undo)
                goto fail_qinode;

        error = init_journal(sdp, undo);
        complete_all(&sdp->sd_journal_ready);
        if (error)
                goto fail;

        /* Read in the resource index inode */
        sdp->sd_rindex = gfs2_lookup_meta(master, "rindex");
        if (IS_ERR(sdp->sd_rindex)) {
                error = PTR_ERR(sdp->sd_rindex);
                fs_err(sdp, "can't get resource index inode: %d\n", error);
                goto fail_journal;
        }
        sdp->sd_rindex_uptodate = 0;

        /* Read in the quota inode */
        sdp->sd_quota_inode = gfs2_lookup_meta(master, "quota");
        if (IS_ERR(sdp->sd_quota_inode)) {
                error = PTR_ERR(sdp->sd_quota_inode);
                fs_err(sdp, "can't get quota file inode: %d\n", error);
                goto fail_rindex;
        }
        /*
         * i_rwsem on quota files is special. Since this inode is hidden system
         * file, we are safe to define locking ourselves.
         */
        lockdep_set_class(&sdp->sd_quota_inode->i_rwsem,
                          &gfs2_quota_imutex_key);

        error = gfs2_rindex_update(sdp);
        if (error)
                goto fail_qinode;

        return 0;

fail_qinode:
        iput(sdp->sd_quota_inode);
fail_rindex:
        gfs2_clear_rgrpd(sdp);
        iput(sdp->sd_rindex);
fail_journal:
        init_journal(sdp, UNDO);
fail:
        return error;
}

static int init_per_node(struct gfs2_sbd *sdp, int undo)
{
        struct inode *pn = NULL;
        char buf[30];
        int error = 0;
        struct gfs2_inode *ip;
        struct inode *master = d_inode(sdp->sd_master_dir);

        if (sdp->sd_args.ar_spectator)
                return 0;

        if (undo)
                goto fail_qc_gh;

        pn = gfs2_lookup_meta(master, "per_node");
        if (IS_ERR(pn)) {
                error = PTR_ERR(pn);
                fs_err(sdp, "can't find per_node directory: %d\n", error);
                return error;
        }

        sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
        sdp->sd_qc_inode = gfs2_lookup_meta(pn, buf);
        if (IS_ERR(sdp->sd_qc_inode)) {
                error = PTR_ERR(sdp->sd_qc_inode);
                fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
                goto fail_ut_i;
        }

        iput(pn);
        pn = NULL;

        ip = GFS2_I(sdp->sd_qc_inode);
        error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_NOPID,
                                   &sdp->sd_qc_gh);
        if (error) {
                fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
                goto fail_qc_i;
        }

        return 0;

fail_qc_gh:
        gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
fail_qc_i:
        iput(sdp->sd_qc_inode);
fail_ut_i:
        iput(pn);
        return error;
}

static const match_table_t nolock_tokens = {
        { Opt_jid, "jid=%d", },
        { Opt_err, NULL },
};

static const struct lm_lockops nolock_ops = {
        .lm_proto_name = "lock_nolock",
        .lm_put_lock = gfs2_glock_free,
        .lm_tokens = &nolock_tokens,
};

/**
 * gfs2_lm_mount - mount a locking protocol
 * @sdp: the filesystem
 * @silent: if 1, don't complain if the FS isn't a GFS2 fs
 *
 * Returns: errno
 */

static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
{
        const struct lm_lockops *lm;
        struct lm_lockstruct *ls = &sdp->sd_lockstruct;
        struct gfs2_args *args = &sdp->sd_args;
        const char *proto = sdp->sd_proto_name;
        const char *table = sdp->sd_table_name;
        char *o, *options;
        int ret;

        if (!strcmp("lock_nolock", proto)) {
                lm = &nolock_ops;
                sdp->sd_args.ar_localflocks = 1;
#ifdef CONFIG_GFS2_FS_LOCKING_DLM
        } else if (!strcmp("lock_dlm", proto)) {
                lm = &gfs2_dlm_ops;
#endif
        } else {
                pr_info("can't find protocol %s\n", proto);
                return -ENOENT;
        }

        fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);

        ls->ls_ops = lm;
        ls->ls_first = 1;

        for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
                substring_t tmp[MAX_OPT_ARGS];
                int token, option;

                if (!o || !*o)
                        continue;

                token = match_token(o, *lm->lm_tokens, tmp);
                switch (token) {
                case Opt_jid:
                        ret = match_int(&tmp[0], &option);
                        if (ret || option < 0) 
                                goto hostdata_error;
                        if (test_and_clear_bit(SDF_NOJOURNALID, &sdp->sd_flags))
                                ls->ls_jid = option;
                        break;
                case Opt_id:
                case Opt_nodir:
                        /* Obsolete, but left for backward compat purposes */
                        break;
                case Opt_first:
                        ret = match_int(&tmp[0], &option);
                        if (ret || (option != 0 && option != 1))
                                goto hostdata_error;
                        ls->ls_first = option;
                        break;
                case Opt_err:
                default:
hostdata_error:
                        fs_info(sdp, "unknown hostdata (%s)\n", o);
                        return -EINVAL;
                }
        }

        if (lm->lm_mount == NULL) {
                fs_info(sdp, "Now mounting FS (format %u)...\n", sdp->sd_sb.sb_fs_format);
                complete_all(&sdp->sd_locking_init);
                return 0;
        }
        ret = lm->lm_mount(sdp, table);
        if (ret == 0)
                fs_info(sdp, "Joined cluster. Now mounting FS (format %u)...\n",
                        sdp->sd_sb.sb_fs_format);
        complete_all(&sdp->sd_locking_init);
        return ret;
}

void gfs2_lm_unmount(struct gfs2_sbd *sdp)
{
        const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
        if (!gfs2_withdrawn(sdp) && lm->lm_unmount)
                lm->lm_unmount(sdp, true);
}

static int wait_on_journal(struct gfs2_sbd *sdp)
{
        if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
                return 0;

        return wait_on_bit(&sdp->sd_flags, SDF_NOJOURNALID, TASK_INTERRUPTIBLE)
                ? -EINTR : 0;
}

void gfs2_online_uevent(struct gfs2_sbd *sdp)
{
        struct super_block *sb = sdp->sd_vfs;
        char ro[20];
        char spectator[20];
        char *envp[] = { ro, spectator, NULL };
        sprintf(ro, "RDONLY=%d", sb_rdonly(sb));
        sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
        kobject_uevent_env(&sdp->sd_kobj, KOBJ_ONLINE, envp);
}

static int init_threads(struct gfs2_sbd *sdp)
{
        struct task_struct *p;
        int error = 0;

        p = kthread_create(gfs2_logd, sdp, "gfs2_logd/%s", sdp->sd_fsname);
        if (IS_ERR(p)) {
                error = PTR_ERR(p);
                fs_err(sdp, "can't create logd thread: %d\n", error);
                return error;
        }
        get_task_struct(p);
        sdp->sd_logd_process = p;

        p = kthread_create(gfs2_quotad, sdp, "gfs2_quotad/%s", sdp->sd_fsname);
        if (IS_ERR(p)) {
                error = PTR_ERR(p);
                fs_err(sdp, "can't create quotad thread: %d\n", error);
                goto fail;
        }
        get_task_struct(p);
        sdp->sd_quotad_process = p;

        wake_up_process(sdp->sd_logd_process);
        wake_up_process(sdp->sd_quotad_process);
        return 0;

fail:
        kthread_stop_put(sdp->sd_logd_process);
        sdp->sd_logd_process = NULL;
        return error;
}

void gfs2_destroy_threads(struct gfs2_sbd *sdp)
{
        if (sdp->sd_logd_process) {
                kthread_stop_put(sdp->sd_logd_process);
                sdp->sd_logd_process = NULL;
        }
        if (sdp->sd_quotad_process) {
                kthread_stop_put(sdp->sd_quotad_process);
                sdp->sd_quotad_process = NULL;
        }
}

/**
 * gfs2_fill_super - Read in superblock
 * @sb: The VFS superblock
 * @fc: Mount options and flags
 *
 * Returns: -errno
 */
static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc)
{
        struct gfs2_args *args = fc->fs_private;
        int silent = fc->sb_flags & SB_SILENT;
        struct gfs2_sbd *sdp;
        struct gfs2_holder mount_gh;
        struct address_space *mapping;
        int error;

        sdp = init_sbd(sb);
        if (!sdp) {
                pr_warn("can't alloc struct gfs2_sbd\n");
                return -ENOMEM;
        }
        sdp->sd_args = *args;

        if (sdp->sd_args.ar_spectator) {
                sb->s_flags |= SB_RDONLY;
                set_bit(SDF_RORECOVERY, &sdp->sd_flags);
        }
        if (sdp->sd_args.ar_posix_acl)
                sb->s_flags |= SB_POSIXACL;
        if (sdp->sd_args.ar_nobarrier)
                set_bit(SDF_NOBARRIERS, &sdp->sd_flags);

        sb->s_flags |= SB_NOSEC;
        sb->s_magic = GFS2_MAGIC;
        sb->s_op = &gfs2_super_ops;

        set_default_d_op(sb, &gfs2_dops);
        sb->s_export_op = &gfs2_export_ops;
        sb->s_qcop = &gfs2_quotactl_ops;
        sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
        sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
        sb->s_time_gran = 1;
        sb->s_maxbytes = MAX_LFS_FILESIZE;

        /* Set up the buffer cache and fill in some fake block size values
           to allow us to read-in the on-disk superblock. */
        sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, SECTOR_SIZE);
        error = -EINVAL;
        if (!sdp->sd_sb.sb_bsize)
                goto fail_free;
        sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
        sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift - SECTOR_SHIFT;
        sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);

        sdp->sd_tune.gt_logd_secs = sdp->sd_args.ar_commit;
        sdp->sd_tune.gt_quota_quantum = sdp->sd_args.ar_quota_quantum;
        if (sdp->sd_args.ar_statfs_quantum) {
                sdp->sd_tune.gt_statfs_slow = 0;
                sdp->sd_tune.gt_statfs_quantum = sdp->sd_args.ar_statfs_quantum;
        } else {
                sdp->sd_tune.gt_statfs_slow = 1;
                sdp->sd_tune.gt_statfs_quantum = 30;
        }

        /* Set up an address space for metadata writes */
        sdp->sd_inode = new_inode(sb);
        error = -ENOMEM;
        if (!sdp->sd_inode)
                goto fail_free;
        sdp->sd_inode->i_ino = GFS2_BAD_INO;
        sdp->sd_inode->i_size = OFFSET_MAX;

        mapping = gfs2_aspace(sdp);
        mapping->a_ops = &gfs2_rgrp_aops;
        gfs2_setup_inode(sdp->sd_inode);

        error = init_names(sdp, silent);
        if (error)
                goto fail_iput;

        snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s", sdp->sd_table_name);

        error = -ENOMEM;
        sdp->sd_glock_wq = alloc_workqueue("gfs2-glock/%s",
                        WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_FREEZABLE | WQ_PERCPU,
                        0,
                        sdp->sd_fsname);
        if (!sdp->sd_glock_wq)
                goto fail_iput;

        sdp->sd_delete_wq = alloc_workqueue("gfs2-delete/%s",
                        WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_PERCPU, 0,
                        sdp->sd_fsname);
        if (!sdp->sd_delete_wq)
                goto fail_glock_wq;

        error = gfs2_sys_fs_add(sdp);
        if (error)
                goto fail_delete_wq;

        gfs2_create_debugfs_file(sdp);

        error = gfs2_lm_mount(sdp, silent);
        if (error)
                goto fail_debug;

        INIT_WORK(&sdp->sd_withdraw_work, gfs2_withdraw_func);

        error = init_locking(sdp, &mount_gh, DO);
        if (error)
                goto fail_lm;

        error = init_sb(sdp, silent);
        if (error)
                goto fail_locking;

        /* Turn rgrplvb on by default if fs format is recent enough */
        if (!sdp->sd_args.ar_got_rgrplvb && sdp->sd_sb.sb_fs_format > 1801)
                sdp->sd_args.ar_rgrplvb = 1;

        error = wait_on_journal(sdp);
        if (error)
                goto fail_sb;

        /*
         * If user space has failed to join the cluster or some similar
         * failure has occurred, then the journal id will contain a
         * negative (error) number. This will then be returned to the
         * caller (of the mount syscall). We do this even for spectator
         * mounts (which just write a jid of 0 to indicate "ok" even though
         * the jid is unused in the spectator case)
         */
        if (sdp->sd_lockstruct.ls_jid < 0) {
                error = sdp->sd_lockstruct.ls_jid;
                sdp->sd_lockstruct.ls_jid = 0;
                goto fail_sb;
        }

        if (sdp->sd_args.ar_spectator)
                snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.s",
                         sdp->sd_table_name);
        else
                snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.%u",
                         sdp->sd_table_name, sdp->sd_lockstruct.ls_jid);

        error = init_inodes(sdp, DO);
        if (error)
                goto fail_sb;

        error = init_per_node(sdp, DO);
        if (error)
                goto fail_inodes;

        error = gfs2_statfs_init(sdp);
        if (error) {
                fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
                goto fail_per_node;
        }

        if (!sb_rdonly(sb)) {
                error = init_threads(sdp);
                if (error)
                        goto fail_per_node;
        }

        error = gfs2_freeze_lock_shared(sdp);
        if (error)
                goto fail_per_node;

        if (!sb_rdonly(sb))
                error = gfs2_make_fs_rw(sdp);

        if (error) {
                gfs2_freeze_unlock(sdp);
                fs_err(sdp, "can't make FS RW: %d\n", error);
                goto fail_per_node;
        }
        gfs2_glock_dq_uninit(&mount_gh);
        gfs2_online_uevent(sdp);
        return 0;

fail_per_node:
        init_per_node(sdp, UNDO);
        gfs2_destroy_threads(sdp);
fail_inodes:
        init_inodes(sdp, UNDO);
fail_sb:
        if (sdp->sd_root_dir)
                dput(sdp->sd_root_dir);
        if (sdp->sd_master_dir)
                dput(sdp->sd_master_dir);
        if (sb->s_root)
                dput(sb->s_root);
        sb->s_root = NULL;
fail_locking:
        init_locking(sdp, &mount_gh, UNDO);
fail_lm:
        complete_all(&sdp->sd_journal_ready);
        gfs2_gl_hash_clear(sdp);
        gfs2_lm_unmount(sdp);
fail_debug:
        gfs2_delete_debugfs_file(sdp);
        gfs2_sys_fs_del(sdp);
fail_delete_wq:
        destroy_workqueue(sdp->sd_delete_wq);
fail_glock_wq:
        if (sdp->sd_glock_wq)
                destroy_workqueue(sdp->sd_glock_wq);
fail_iput:
        iput(sdp->sd_inode);
fail_free:
        free_sbd(sdp);
        return error;
}

/**
 * gfs2_get_tree - Get the GFS2 superblock and root directory
 * @fc: The filesystem context
 *
 * Returns: 0 or -errno on error
 */
static int gfs2_get_tree(struct fs_context *fc)
{
        struct gfs2_args *args = fc->fs_private;
        struct gfs2_sbd *sdp;
        int error;

        error = get_tree_bdev(fc, gfs2_fill_super);
        if (error)
                return error;

        sdp = fc->root->d_sb->s_fs_info;
        dput(fc->root);
        if (args->ar_meta)
                fc->root = dget(sdp->sd_master_dir);
        else
                fc->root = dget(sdp->sd_root_dir);
        return 0;
}

static void gfs2_fc_free(struct fs_context *fc)
{
        struct gfs2_args *args = fc->fs_private;

        kfree(args);
}

enum gfs2_param {
        Opt_lockproto,
        Opt_locktable,
        Opt_hostdata,
        Opt_spectator,
        Opt_ignore_local_fs,
        Opt_localflocks,
        Opt_localcaching,
        Opt_debug,
        Opt_upgrade,
        Opt_acl,
        Opt_quota,
        Opt_quota_flag,
        Opt_suiddir,
        Opt_data,
        Opt_meta,
        Opt_discard,
        Opt_commit,
        Opt_errors,
        Opt_statfs_quantum,
        Opt_statfs_percent,
        Opt_quota_quantum,
        Opt_barrier,
        Opt_rgrplvb,
        Opt_loccookie,
};

static const struct constant_table gfs2_param_quota[] = {
        {"off",        GFS2_QUOTA_OFF},
        {"account",    GFS2_QUOTA_ACCOUNT},
        {"on",         GFS2_QUOTA_ON},
        {"quiet",      GFS2_QUOTA_QUIET},
        {}
};

enum opt_data {
        Opt_data_writeback = GFS2_DATA_WRITEBACK,
        Opt_data_ordered   = GFS2_DATA_ORDERED,
};

static const struct constant_table gfs2_param_data[] = {
        {"writeback",  Opt_data_writeback },
        {"ordered",    Opt_data_ordered },
        {}
};

enum opt_errors {
        Opt_errors_withdraw   = GFS2_ERRORS_WITHDRAW,
        Opt_errors_deactivate = GFS2_ERRORS_DEACTIVATE,
        Opt_errors_panic      = GFS2_ERRORS_PANIC,
};

static const struct constant_table gfs2_param_errors[] = {
        {"withdraw",   Opt_errors_withdraw },
        {"deactivate", Opt_errors_deactivate },
        {"panic",      Opt_errors_panic },
        {}
};

static const struct fs_parameter_spec gfs2_fs_parameters[] = {
        fsparam_string ("lockproto",          Opt_lockproto),
        fsparam_string ("locktable",          Opt_locktable),
        fsparam_string ("hostdata",           Opt_hostdata),
        fsparam_flag   ("spectator",          Opt_spectator),
        fsparam_flag   ("norecovery",         Opt_spectator),
        fsparam_flag   ("ignore_local_fs",    Opt_ignore_local_fs),
        fsparam_flag   ("localflocks",        Opt_localflocks),
        fsparam_flag   ("localcaching",       Opt_localcaching),
        fsparam_flag_no("debug",              Opt_debug),
        fsparam_flag   ("upgrade",            Opt_upgrade),
        fsparam_flag_no("acl",                Opt_acl),
        fsparam_flag_no("suiddir",            Opt_suiddir),
        fsparam_enum   ("data",               Opt_data, gfs2_param_data),
        fsparam_flag   ("meta",               Opt_meta),
        fsparam_flag_no("discard",            Opt_discard),
        fsparam_s32    ("commit",             Opt_commit),
        fsparam_enum   ("errors",             Opt_errors, gfs2_param_errors),
        fsparam_s32    ("statfs_quantum",     Opt_statfs_quantum),
        fsparam_s32    ("statfs_percent",     Opt_statfs_percent),
        fsparam_s32    ("quota_quantum",      Opt_quota_quantum),
        fsparam_flag_no("barrier",            Opt_barrier),
        fsparam_flag_no("rgrplvb",            Opt_rgrplvb),
        fsparam_flag_no("loccookie",          Opt_loccookie),
        /* quota can be a flag or an enum so it gets special treatment */
        fsparam_flag_no("quota",              Opt_quota_flag),
        fsparam_enum("quota",                 Opt_quota, gfs2_param_quota),
        {}
};

/* Parse a single mount parameter */
static int gfs2_parse_param(struct fs_context *fc, struct fs_parameter *param)
{
        struct gfs2_args *args = fc->fs_private;
        struct fs_parse_result result;
        int o;

        o = fs_parse(fc, gfs2_fs_parameters, param, &result);
        if (o < 0)
                return o;

        switch (o) {
        case Opt_lockproto:
                strscpy(args->ar_lockproto, param->string, GFS2_LOCKNAME_LEN);
                break;
        case Opt_locktable:
                strscpy(args->ar_locktable, param->string, GFS2_LOCKNAME_LEN);
                break;
        case Opt_hostdata:
                strscpy(args->ar_hostdata, param->string, 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 (result.boolean && args->ar_errors == GFS2_ERRORS_PANIC)
                        return invalfc(fc, "-o debug and -o errors=panic are mutually exclusive");
                args->ar_debug = result.boolean;
                break;
        case Opt_upgrade:
                /* Retained for backwards compat only */
                break;
        case Opt_acl:
                args->ar_posix_acl = result.boolean;
                break;
        case Opt_quota_flag:
                args->ar_quota = result.negated ? GFS2_QUOTA_OFF : GFS2_QUOTA_ON;
                break;
        case Opt_quota:
                args->ar_quota = result.int_32;
                break;
        case Opt_suiddir:
                args->ar_suiddir = result.boolean;
                break;
        case Opt_data:
                /* The uint_32 result maps directly to GFS2_DATA_* */
                args->ar_data = result.uint_32;
                break;
        case Opt_meta:
                args->ar_meta = 1;
                break;
        case Opt_discard:
                args->ar_discard = result.boolean;
                break;
        case Opt_commit:
                if (result.int_32 <= 0)
                        return invalfc(fc, "commit mount option requires a positive numeric argument");
                args->ar_commit = result.int_32;
                break;
        case Opt_statfs_quantum:
                if (result.int_32 < 0)
                        return invalfc(fc, "statfs_quantum mount option requires a non-negative numeric argument");
                args->ar_statfs_quantum = result.int_32;
                break;
        case Opt_quota_quantum:
                if (result.int_32 <= 0)
                        return invalfc(fc, "quota_quantum mount option requires a positive numeric argument");
                args->ar_quota_quantum = result.int_32;
                break;
        case Opt_statfs_percent:
                if (result.int_32 < 0 || result.int_32 > 100)
                        return invalfc(fc, "statfs_percent mount option requires a numeric argument between 0 and 100");
                args->ar_statfs_percent = result.int_32;
                break;
        case Opt_errors:
                if (args->ar_debug && result.uint_32 == GFS2_ERRORS_PANIC)
                        return invalfc(fc, "-o debug and -o errors=panic are mutually exclusive");
                args->ar_errors = result.uint_32;
                break;
        case Opt_barrier:
                args->ar_nobarrier = result.boolean;
                break;
        case Opt_rgrplvb:
                args->ar_rgrplvb = result.boolean;
                args->ar_got_rgrplvb = 1;
                break;
        case Opt_loccookie:
                args->ar_loccookie = result.boolean;
                break;
        default:
                return invalfc(fc, "invalid mount option: %s", param->key);
        }
        return 0;
}

static int gfs2_reconfigure(struct fs_context *fc)
{
        struct super_block *sb = fc->root->d_sb;
        struct gfs2_sbd *sdp = sb->s_fs_info;
        struct gfs2_args *oldargs = &sdp->sd_args;
        struct gfs2_args *newargs = fc->fs_private;
        struct gfs2_tune *gt = &sdp->sd_tune;
        int error = 0;

        sync_filesystem(sb);

        spin_lock(&gt->gt_spin);
        oldargs->ar_commit = gt->gt_logd_secs;
        oldargs->ar_quota_quantum = gt->gt_quota_quantum;
        if (gt->gt_statfs_slow)
                oldargs->ar_statfs_quantum = 0;
        else
                oldargs->ar_statfs_quantum = gt->gt_statfs_quantum;
        spin_unlock(&gt->gt_spin);

        if (strcmp(newargs->ar_lockproto, oldargs->ar_lockproto)) {
                errorfc(fc, "reconfiguration of locking protocol not allowed");
                return -EINVAL;
        }
        if (strcmp(newargs->ar_locktable, oldargs->ar_locktable)) {
                errorfc(fc, "reconfiguration of lock table not allowed");
                return -EINVAL;
        }
        if (strcmp(newargs->ar_hostdata, oldargs->ar_hostdata)) {
                errorfc(fc, "reconfiguration of host data not allowed");
                return -EINVAL;
        }
        if (newargs->ar_spectator != oldargs->ar_spectator) {
                errorfc(fc, "reconfiguration of spectator mode not allowed");
                return -EINVAL;
        }
        if (newargs->ar_localflocks != oldargs->ar_localflocks) {
                errorfc(fc, "reconfiguration of localflocks not allowed");
                return -EINVAL;
        }
        if (newargs->ar_meta != oldargs->ar_meta) {
                errorfc(fc, "switching between gfs2 and gfs2meta not allowed");
                return -EINVAL;
        }
        if (oldargs->ar_spectator)
                fc->sb_flags |= SB_RDONLY;

        if ((sb->s_flags ^ fc->sb_flags) & SB_RDONLY) {
                if (fc->sb_flags & SB_RDONLY) {
                        gfs2_make_fs_ro(sdp);
                } else {
                        error = gfs2_make_fs_rw(sdp);
                        if (error)
                                errorfc(fc, "unable to remount read-write");
                }
        }
        sdp->sd_args = *newargs;

        if (sdp->sd_args.ar_posix_acl)
                sb->s_flags |= SB_POSIXACL;
        else
                sb->s_flags &= ~SB_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 = newargs->ar_commit;
        gt->gt_quota_quantum = newargs->ar_quota_quantum;
        if (newargs->ar_statfs_quantum) {
                gt->gt_statfs_slow = 0;
                gt->gt_statfs_quantum = newargs->ar_statfs_quantum;
        }
        else {
                gt->gt_statfs_slow = 1;
                gt->gt_statfs_quantum = 30;
        }
        spin_unlock(&gt->gt_spin);

        gfs2_online_uevent(sdp);
        return error;
}

static const struct fs_context_operations gfs2_context_ops = {
        .free        = gfs2_fc_free,
        .parse_param = gfs2_parse_param,
        .get_tree    = gfs2_get_tree,
        .reconfigure = gfs2_reconfigure,
};

/* Set up the filesystem mount context */
static int gfs2_init_fs_context(struct fs_context *fc)
{
        struct gfs2_args *args;

        args = kmalloc_obj(*args);
        if (args == NULL)
                return -ENOMEM;

        if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
                struct gfs2_sbd *sdp = fc->root->d_sb->s_fs_info;

                *args = sdp->sd_args;
        } else {
                memset(args, 0, sizeof(*args));
                args->ar_quota = GFS2_QUOTA_DEFAULT;
                args->ar_data = GFS2_DATA_DEFAULT;
                args->ar_commit = 30;
                args->ar_statfs_quantum = 30;
                args->ar_quota_quantum = 60;
                args->ar_errors = GFS2_ERRORS_DEFAULT;
        }
        fc->fs_private = args;
        fc->ops = &gfs2_context_ops;
        return 0;
}

static int set_meta_super(struct super_block *s, struct fs_context *fc)
{
        return -EINVAL;
}

static int test_meta_super(struct super_block *s, struct fs_context *fc)
{
        return (fc->sget_key == s->s_bdev);
}

static int gfs2_meta_get_tree(struct fs_context *fc)
{
        struct super_block *s;
        struct gfs2_sbd *sdp;
        struct path path;
        int error;

        if (!fc->source || !*fc->source)
                return -EINVAL;

        error = kern_path(fc->source, LOOKUP_FOLLOW, &path);
        if (error) {
                pr_warn("path_lookup on %s returned error %d\n",
                        fc->source, error);
                return error;
        }
        fc->fs_type = &gfs2_fs_type;
        fc->sget_key = path.dentry->d_sb->s_bdev;
        s = sget_fc(fc, test_meta_super, set_meta_super);
        path_put(&path);
        if (IS_ERR(s)) {
                pr_warn("gfs2 mount does not exist\n");
                return PTR_ERR(s);
        }
        if ((fc->sb_flags ^ s->s_flags) & SB_RDONLY) {
                deactivate_locked_super(s);
                return -EBUSY;
        }
        sdp = s->s_fs_info;
        fc->root = dget(sdp->sd_master_dir);
        return 0;
}

static const struct fs_context_operations gfs2_meta_context_ops = {
        .free        = gfs2_fc_free,
        .get_tree    = gfs2_meta_get_tree,
};

static int gfs2_meta_init_fs_context(struct fs_context *fc)
{
        int ret = gfs2_init_fs_context(fc);

        if (ret)
                return ret;

        fc->ops = &gfs2_meta_context_ops;
        return 0;
}

/**
 * gfs2_evict_inodes - evict inodes cooperatively
 * @sb: the superblock
 *
 * When evicting an inode with a zero link count, we are trying to upgrade the
 * inode's iopen glock from SH to EX mode in order to determine if we can
 * delete the inode.  The other nodes are supposed to evict the inode from
 * their caches if they can, and to poke the inode's inode glock if they cannot
 * do so.  Either behavior allows gfs2_upgrade_iopen_glock() to proceed
 * quickly, but if the other nodes are not cooperating, the lock upgrading
 * attempt will time out.  Since inodes are evicted sequentially, this can add
 * up quickly.
 *
 * Function evict_inodes() tries to keep the s_inode_list_lock list locked over
 * a long time, which prevents other inodes from being evicted concurrently.
 * This precludes the cooperative behavior we are looking for.  This special
 * version of evict_inodes() avoids that.
 *
 * Modeled after drop_pagecache_sb().
 */
static void gfs2_evict_inodes(struct super_block *sb)
{
        struct inode *inode, *toput_inode = NULL;
        struct gfs2_sbd *sdp = sb->s_fs_info;

        set_bit(SDF_EVICTING, &sdp->sd_flags);

        spin_lock(&sb->s_inode_list_lock);
        list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
                spin_lock(&inode->i_lock);
                if ((inode_state_read(inode) & (I_FREEING | I_WILL_FREE | I_NEW)) &&
                    !need_resched()) {
                        spin_unlock(&inode->i_lock);
                        continue;
                }
                __iget(inode);
                spin_unlock(&inode->i_lock);
                spin_unlock(&sb->s_inode_list_lock);

                iput(toput_inode);
                toput_inode = inode;

                cond_resched();
                spin_lock(&sb->s_inode_list_lock);
        }
        spin_unlock(&sb->s_inode_list_lock);
        iput(toput_inode);
}

static void gfs2_kill_sb(struct super_block *sb)
{
        struct gfs2_sbd *sdp = sb->s_fs_info;

        if (sdp == NULL) {
                kill_block_super(sb);
                return;
        }

        gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SYNC | GFS2_LFC_KILL_SB);
        dput(sdp->sd_root_dir);
        dput(sdp->sd_master_dir);
        sdp->sd_root_dir = NULL;
        sdp->sd_master_dir = NULL;
        shrink_dcache_sb(sb);

        gfs2_evict_inodes(sb);

        /*
         * Flush and then drain the delete workqueue here (via
         * destroy_workqueue()) to ensure that any delete work that
         * may be running will also see the SDF_KILL flag.
         */
        set_bit(SDF_KILL, &sdp->sd_flags);
        gfs2_flush_delete_work(sdp);
        destroy_workqueue(sdp->sd_delete_wq);

        kill_block_super(sb);
}

struct file_system_type gfs2_fs_type = {
        .name = "gfs2",
        .fs_flags = FS_REQUIRES_DEV,
        .init_fs_context = gfs2_init_fs_context,
        .parameters = gfs2_fs_parameters,
        .kill_sb = gfs2_kill_sb,
        .owner = THIS_MODULE,
};
MODULE_ALIAS_FS("gfs2");

struct file_system_type gfs2meta_fs_type = {
        .name = "gfs2meta",
        .fs_flags = FS_REQUIRES_DEV,
        .init_fs_context = gfs2_meta_init_fs_context,
        .owner = THIS_MODULE,
};
MODULE_ALIAS_FS("gfs2meta");