resize.c

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/* -*- mode: c; c-basic-offset: 8; -*-
 * vim: noexpandtab sw=8 ts=8 sts=0:
 *
 * resize.c
 *
 * volume resize.
 * Inspired by ext3/resize.c.
 *
 * Copyright (C) 2007 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#include <linux/fs.h>
#include <linux/types.h>

#include <cluster/masklog.h>

#include "ocfs2.h"

#include "alloc.h"
#include "dlmglue.h"
#include "inode.h"
#include "journal.h"
#include "super.h"
#include "sysfile.h"
#include "uptodate.h"
#include "ocfs2_trace.h"

#include "buffer_head_io.h"
#include "suballoc.h"
#include "resize.h"

/*
 * Check whether there are new backup superblocks exist
 * in the last group. If there are some, mark them or clear
 * them in the bitmap.
 *
 * Return how many backups we find in the last group.
 */
static u16 ocfs2_calc_new_backup_super(struct inode *inode,
                       struct ocfs2_group_desc *gd,
                       int new_clusters,
                       u32 first_new_cluster,
                       u16 cl_cpg,
                       int set)
{
    int i;
    u16 backups = 0;
    u32 cluster;
    u64 blkno, gd_blkno, lgd_blkno = le64_to_cpu(gd->bg_blkno);

    for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
        blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
        cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);

        gd_blkno = ocfs2_which_cluster_group(inode, cluster);
        if (gd_blkno < lgd_blkno)
            continue;
        else if (gd_blkno > lgd_blkno)
            break;

        if (set)
            ocfs2_set_bit(cluster % cl_cpg,
                      (unsigned long *)gd->bg_bitmap);
        else
            ocfs2_clear_bit(cluster % cl_cpg,
                    (unsigned long *)gd->bg_bitmap);
        backups++;
    }

    return backups;
}

static int ocfs2_update_last_group_and_inode(handle_t *handle,
                         struct inode *bm_inode,
                         struct buffer_head *bm_bh,
                         struct buffer_head *group_bh,
                         u32 first_new_cluster,
                         int new_clusters)
{
    int ret = 0;
    struct ocfs2_super *osb = OCFS2_SB(bm_inode->i_sb);
    struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bm_bh->b_data;
    struct ocfs2_chain_list *cl = &fe->id2.i_chain;
    struct ocfs2_chain_rec *cr;
    struct ocfs2_group_desc *group;
    u16 chain, num_bits, backups = 0;
    u16 cl_bpc = le16_to_cpu(cl->cl_bpc);
    u16 cl_cpg = le16_to_cpu(cl->cl_cpg);

    trace_ocfs2_update_last_group_and_inode(new_clusters,
                        first_new_cluster);

    ret = ocfs2_journal_access_gd(handle, INODE_CACHE(bm_inode),
                      group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
    if (ret < 0) {
        mlog_errno(ret);
        goto out;
    }

    group = (struct ocfs2_group_desc *)group_bh->b_data;

    /* update the group first. */
    num_bits = new_clusters * cl_bpc;
    le16_add_cpu(&group->bg_bits, num_bits);
    le16_add_cpu(&group->bg_free_bits_count, num_bits);

    /*
     * check whether there are some new backup superblocks exist in
     * this group and update the group bitmap accordingly.
     */
    if (OCFS2_HAS_COMPAT_FEATURE(osb->sb,
                     OCFS2_FEATURE_COMPAT_BACKUP_SB)) {
        backups = ocfs2_calc_new_backup_super(bm_inode,
                             group,
                             new_clusters,
                             first_new_cluster,
                             cl_cpg, 1);
        le16_add_cpu(&group->bg_free_bits_count, -1 * backups);
    }

    ocfs2_journal_dirty(handle, group_bh);

    /* update the inode accordingly. */
    ret = ocfs2_journal_access_di(handle, INODE_CACHE(bm_inode), bm_bh,
                      OCFS2_JOURNAL_ACCESS_WRITE);
    if (ret < 0) {
        mlog_errno(ret);
        goto out_rollback;
    }

    chain = le16_to_cpu(group->bg_chain);
    cr = (&cl->cl_recs[chain]);
    le32_add_cpu(&cr->c_total, num_bits);
    le32_add_cpu(&cr->c_free, num_bits);
    le32_add_cpu(&fe->id1.bitmap1.i_total, num_bits);
    le32_add_cpu(&fe->i_clusters, new_clusters);

    if (backups) {
        le32_add_cpu(&cr->c_free, -1 * backups);
        le32_add_cpu(&fe->id1.bitmap1.i_used, backups);
    }

    spin_lock(&OCFS2_I(bm_inode)->ip_lock);
    OCFS2_I(bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
    le64_add_cpu(&fe->i_size, new_clusters << osb->s_clustersize_bits);
    spin_unlock(&OCFS2_I(bm_inode)->ip_lock);
    i_size_write(bm_inode, le64_to_cpu(fe->i_size));

    ocfs2_journal_dirty(handle, bm_bh);

out_rollback:
    if (ret < 0) {
        ocfs2_calc_new_backup_super(bm_inode,
                        group,
                        new_clusters,
                        first_new_cluster,
                        cl_cpg, 0);
        le16_add_cpu(&group->bg_free_bits_count, backups);
        le16_add_cpu(&group->bg_bits, -1 * num_bits);
        le16_add_cpu(&group->bg_free_bits_count, -1 * num_bits);
    }
out:
    if (ret)
        mlog_errno(ret);
    return ret;
}

static int update_backups(struct inode * inode, u32 clusters, char *data)
{
    int i, ret = 0;
    u32 cluster;
    u64 blkno;
    struct buffer_head *backup = NULL;
    struct ocfs2_dinode *backup_di = NULL;
    struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);

    /* calculate the real backups we need to update. */
    for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
        blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
        cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
        if (cluster > clusters)
            break;

        ret = ocfs2_read_blocks_sync(osb, blkno, 1, &backup);
        if (ret < 0) {
            mlog_errno(ret);
            break;
        }

        memcpy(backup->b_data, data, inode->i_sb->s_blocksize);

        backup_di = (struct ocfs2_dinode *)backup->b_data;
        backup_di->i_blkno = cpu_to_le64(blkno);

        ret = ocfs2_write_super_or_backup(osb, backup);
        brelse(backup);
        backup = NULL;
        if (ret < 0) {
            mlog_errno(ret);
            break;
        }
    }

    return ret;
}

static void ocfs2_update_super_and_backups(struct inode *inode,
                       int new_clusters)
{
    int ret;
    u32 clusters = 0;
    struct buffer_head *super_bh = NULL;
    struct ocfs2_dinode *super_di = NULL;
    struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);

    /*
     * update the superblock last.
     * It doesn't matter if the write failed.
     */
    ret = ocfs2_read_blocks_sync(osb, OCFS2_SUPER_BLOCK_BLKNO, 1,
                     &super_bh);
    if (ret < 0) {
        mlog_errno(ret);
        goto out;
    }

    super_di = (struct ocfs2_dinode *)super_bh->b_data;
    le32_add_cpu(&super_di->i_clusters, new_clusters);
    clusters = le32_to_cpu(super_di->i_clusters);

    ret = ocfs2_write_super_or_backup(osb, super_bh);
    if (ret < 0) {
        mlog_errno(ret);
        goto out;
    }

    if (OCFS2_HAS_COMPAT_FEATURE(osb->sb, OCFS2_FEATURE_COMPAT_BACKUP_SB))
        ret = update_backups(inode, clusters, super_bh->b_data);

out:
    brelse(super_bh);
    if (ret)
        printk(KERN_WARNING "ocfs2: Failed to update super blocks on %s"
            " during fs resize. This condition is not fatal,"
            " but fsck.ocfs2 should be run to fix it\n",
            osb->dev_str);
    return;
}

/*
 * Extend the filesystem to the new number of clusters specified.  This entry
 * point is only used to extend the current filesystem to the end of the last
 * existing group.
 */
int ocfs2_group_extend(struct inode * inode, int new_clusters)
{
    int ret;
    handle_t *handle;
    struct buffer_head *main_bm_bh = NULL;
    struct buffer_head *group_bh = NULL;
    struct inode *main_bm_inode = NULL;
    struct ocfs2_dinode *fe = NULL;
    struct ocfs2_group_desc *group = NULL;
    struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    u16 cl_bpc;
    u32 first_new_cluster;
    u64 lgd_blkno;

    if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
        return -EROFS;

    if (new_clusters < 0)
        return -EINVAL;
    else if (new_clusters == 0)
        return 0;

    main_bm_inode = ocfs2_get_system_file_inode(osb,
                            GLOBAL_BITMAP_SYSTEM_INODE,
                            OCFS2_INVALID_SLOT);
    if (!main_bm_inode) {
        ret = -EINVAL;
        mlog_errno(ret);
        goto out;
    }

    mutex_lock(&main_bm_inode->i_mutex);

    ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
    if (ret < 0) {
        mlog_errno(ret);
        goto out_mutex;
    }

    fe = (struct ocfs2_dinode *)main_bm_bh->b_data;

    /* main_bm_bh is validated by inode read inside ocfs2_inode_lock(),
     * so any corruption is a code bug. */
    BUG_ON(!OCFS2_IS_VALID_DINODE(fe));

    if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
        ocfs2_group_bitmap_size(osb->sb, 0,
                    osb->s_feature_incompat) * 8) {
        mlog(ML_ERROR, "The disk is too old and small. "
             "Force to do offline resize.");
        ret = -EINVAL;
        goto out_unlock;
    }

    first_new_cluster = le32_to_cpu(fe->i_clusters);
    lgd_blkno = ocfs2_which_cluster_group(main_bm_inode,
                          first_new_cluster - 1);

    ret = ocfs2_read_group_descriptor(main_bm_inode, fe, lgd_blkno,
                      &group_bh);
    if (ret < 0) {
        mlog_errno(ret);
        goto out_unlock;
    }
    group = (struct ocfs2_group_desc *)group_bh->b_data;

    cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
    if (le16_to_cpu(group->bg_bits) / cl_bpc + new_clusters >
        le16_to_cpu(fe->id2.i_chain.cl_cpg)) {
        ret = -EINVAL;
        goto out_unlock;
    }


    trace_ocfs2_group_extend(
         (unsigned long long)le64_to_cpu(group->bg_blkno), new_clusters);

    handle = ocfs2_start_trans(osb, OCFS2_GROUP_EXTEND_CREDITS);
    if (IS_ERR(handle)) {
        mlog_errno(PTR_ERR(handle));
        ret = -EINVAL;
        goto out_unlock;
    }

    /* update the last group descriptor and inode. */
    ret = ocfs2_update_last_group_and_inode(handle, main_bm_inode,
                        main_bm_bh, group_bh,
                        first_new_cluster,
                        new_clusters);
    if (ret) {
        mlog_errno(ret);
        goto out_commit;
    }

    ocfs2_update_super_and_backups(main_bm_inode, new_clusters);

out_commit:
    ocfs2_commit_trans(osb, handle);
out_unlock:
    brelse(group_bh);
    brelse(main_bm_bh);

    ocfs2_inode_unlock(main_bm_inode, 1);

out_mutex:
    mutex_unlock(&main_bm_inode->i_mutex);
    iput(main_bm_inode);

out:
    return ret;
}

static int ocfs2_check_new_group(struct inode *inode,
                 struct ocfs2_dinode *di,
                 struct ocfs2_new_group_input *input,
                 struct buffer_head *group_bh)
{
    int ret;
    struct ocfs2_group_desc *gd =
        (struct ocfs2_group_desc *)group_bh->b_data;
    u16 cl_bpc = le16_to_cpu(di->id2.i_chain.cl_bpc);

    ret = ocfs2_check_group_descriptor(inode->i_sb, di, group_bh);
    if (ret)
        goto out;

    ret = -EINVAL;
    if (le16_to_cpu(gd->bg_chain) != input->chain)
        mlog(ML_ERROR, "Group descriptor # %llu has bad chain %u "
             "while input has %u set.\n",
             (unsigned long long)le64_to_cpu(gd->bg_blkno),
             le16_to_cpu(gd->bg_chain), input->chain);
    else if (le16_to_cpu(gd->bg_bits) != input->clusters * cl_bpc)
        mlog(ML_ERROR, "Group descriptor # %llu has bit count %u but "
             "input has %u clusters set\n",
             (unsigned long long)le64_to_cpu(gd->bg_blkno),
             le16_to_cpu(gd->bg_bits), input->clusters);
    else if (le16_to_cpu(gd->bg_free_bits_count) != input->frees * cl_bpc)
        mlog(ML_ERROR, "Group descriptor # %llu has free bit count %u "
             "but it should have %u set\n",
             (unsigned long long)le64_to_cpu(gd->bg_blkno),
             le16_to_cpu(gd->bg_bits),
             input->frees * cl_bpc);
    else
        ret = 0;

out:
    return ret;
}

static int ocfs2_verify_group_and_input(struct inode *inode,
                    struct ocfs2_dinode *di,
                    struct ocfs2_new_group_input *input,
                    struct buffer_head *group_bh)
{
    u16 cl_count = le16_to_cpu(di->id2.i_chain.cl_count);
    u16 cl_cpg = le16_to_cpu(di->id2.i_chain.cl_cpg);
    u16 next_free = le16_to_cpu(di->id2.i_chain.cl_next_free_rec);
    u32 cluster = ocfs2_blocks_to_clusters(inode->i_sb, input->group);
    u32 total_clusters = le32_to_cpu(di->i_clusters);
    int ret = -EINVAL;

    if (cluster < total_clusters)
        mlog(ML_ERROR, "add a group which is in the current volume.\n");
    else if (input->chain >= cl_count)
        mlog(ML_ERROR, "input chain exceeds the limit.\n");
    else if (next_free != cl_count && next_free != input->chain)
        mlog(ML_ERROR,
             "the add group should be in chain %u\n", next_free);
    else if (total_clusters + input->clusters < total_clusters)
        mlog(ML_ERROR, "add group's clusters overflow.\n");
    else if (input->clusters > cl_cpg)
        mlog(ML_ERROR, "the cluster exceeds the maximum of a group\n");
    else if (input->frees > input->clusters)
        mlog(ML_ERROR, "the free cluster exceeds the total clusters\n");
    else if (total_clusters % cl_cpg != 0)
        mlog(ML_ERROR,
             "the last group isn't full. Use group extend first.\n");
    else if (input->group != ocfs2_which_cluster_group(inode, cluster))
        mlog(ML_ERROR, "group blkno is invalid\n");
    else if ((ret = ocfs2_check_new_group(inode, di, input, group_bh)))
        mlog(ML_ERROR, "group descriptor check failed.\n");
    else
        ret = 0;

    return ret;
}

/* Add a new group descriptor to global_bitmap. */
int ocfs2_group_add(struct inode *inode, struct ocfs2_new_group_input *input)
{
    int ret;
    handle_t *handle;
    struct buffer_head *main_bm_bh = NULL;
    struct inode *main_bm_inode = NULL;
    struct ocfs2_dinode *fe = NULL;
    struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    struct buffer_head *group_bh = NULL;
    struct ocfs2_group_desc *group = NULL;
    struct ocfs2_chain_list *cl;
    struct ocfs2_chain_rec *cr;
    u16 cl_bpc;

    if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
        return -EROFS;

    main_bm_inode = ocfs2_get_system_file_inode(osb,
                            GLOBAL_BITMAP_SYSTEM_INODE,
                            OCFS2_INVALID_SLOT);
    if (!main_bm_inode) {
        ret = -EINVAL;
        mlog_errno(ret);
        goto out;
    }

    mutex_lock(&main_bm_inode->i_mutex);

    ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
    if (ret < 0) {
        mlog_errno(ret);
        goto out_mutex;
    }

    fe = (struct ocfs2_dinode *)main_bm_bh->b_data;

    if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
        ocfs2_group_bitmap_size(osb->sb, 0,
                    osb->s_feature_incompat) * 8) {
        mlog(ML_ERROR, "The disk is too old and small."
             " Force to do offline resize.");
        ret = -EINVAL;
        goto out_unlock;
    }

    ret = ocfs2_read_blocks_sync(osb, input->group, 1, &group_bh);
    if (ret < 0) {
        mlog(ML_ERROR, "Can't read the group descriptor # %llu "
             "from the device.", (unsigned long long)input->group);
        goto out_unlock;
    }

    ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), group_bh);

    ret = ocfs2_verify_group_and_input(main_bm_inode, fe, input, group_bh);
    if (ret) {
        mlog_errno(ret);
        goto out_unlock;
    }

    trace_ocfs2_group_add((unsigned long long)input->group,
                   input->chain, input->clusters, input->frees);

    handle = ocfs2_start_trans(osb, OCFS2_GROUP_ADD_CREDITS);
    if (IS_ERR(handle)) {
        mlog_errno(PTR_ERR(handle));
        ret = -EINVAL;
        goto out_unlock;
    }

    cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
    cl = &fe->id2.i_chain;
    cr = &cl->cl_recs[input->chain];

    ret = ocfs2_journal_access_gd(handle, INODE_CACHE(main_bm_inode),
                      group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
    if (ret < 0) {
        mlog_errno(ret);
        goto out_commit;
    }

    group = (struct ocfs2_group_desc *)group_bh->b_data;
    group->bg_next_group = cr->c_blkno;
    ocfs2_journal_dirty(handle, group_bh);

    ret = ocfs2_journal_access_di(handle, INODE_CACHE(main_bm_inode),
                      main_bm_bh, OCFS2_JOURNAL_ACCESS_WRITE);
    if (ret < 0) {
        mlog_errno(ret);
        goto out_commit;
    }

    if (input->chain == le16_to_cpu(cl->cl_next_free_rec)) {
        le16_add_cpu(&cl->cl_next_free_rec, 1);
        memset(cr, 0, sizeof(struct ocfs2_chain_rec));
    }

    cr->c_blkno = cpu_to_le64(input->group);
    le32_add_cpu(&cr->c_total, input->clusters * cl_bpc);
    le32_add_cpu(&cr->c_free, input->frees * cl_bpc);

    le32_add_cpu(&fe->id1.bitmap1.i_total, input->clusters *cl_bpc);
    le32_add_cpu(&fe->id1.bitmap1.i_used,
             (input->clusters - input->frees) * cl_bpc);
    le32_add_cpu(&fe->i_clusters, input->clusters);

    ocfs2_journal_dirty(handle, main_bm_bh);

    spin_lock(&OCFS2_I(main_bm_inode)->ip_lock);
    OCFS2_I(main_bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
    le64_add_cpu(&fe->i_size, input->clusters << osb->s_clustersize_bits);
    spin_unlock(&OCFS2_I(main_bm_inode)->ip_lock);
    i_size_write(main_bm_inode, le64_to_cpu(fe->i_size));

    ocfs2_update_super_and_backups(main_bm_inode, input->clusters);

out_commit:
    ocfs2_commit_trans(osb, handle);
out_unlock:
    brelse(group_bh);
    brelse(main_bm_bh);

    ocfs2_inode_unlock(main_bm_inode, 1);

out_mutex:
    mutex_unlock(&main_bm_inode->i_mutex);
    iput(main_bm_inode);

out:
    return ret;
}