root/fs/gfs2/trans.c

DEFINITIONS

1. gfs2_trans_begin
2. gfs2_trans_end
3. gfs2_trans_add_bh
4. gfs2_trans_add_revoke
5. gfs2_trans_add_unrevoke
6. gfs2_trans_add_rg

/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2006 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/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/gfs2_ondisk.h>
#include <linux/kallsyms.h>
#include <linux/lm_interface.h>

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

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

        BUG_ON(current->journal_info);
        BUG_ON(blocks == 0 && revokes == 0);

        tr = kzalloc(sizeof(struct gfs2_trans), GFP_NOFS);
        if (!tr)
                return -ENOMEM;

        tr->tr_ip = (unsigned long)__builtin_return_address(0);
        tr->tr_blocks = blocks;
        tr->tr_revokes = revokes;
        tr->tr_reserved = 1;
        if (blocks)
                tr->tr_reserved += 6 + blocks;
        if (revokes)
                tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
                                                   sizeof(u64));
        INIT_LIST_HEAD(&tr->tr_list_buf);

        gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh);

        error = gfs2_glock_nq(&tr->tr_t_gh);
        if (error)
                goto fail_holder_uninit;

        if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
                tr->tr_t_gh.gh_flags |= GL_NOCACHE;
                error = -EROFS;
                goto fail_gunlock;
        }

        error = gfs2_log_reserve(sdp, tr->tr_reserved);
        if (error)
                goto fail_gunlock;

        current->journal_info = tr;

        return 0;

fail_gunlock:
        gfs2_glock_dq(&tr->tr_t_gh);

fail_holder_uninit:
        gfs2_holder_uninit(&tr->tr_t_gh);
        kfree(tr);

        return error;
}

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

        BUG_ON(!tr);
        current->journal_info = NULL;

        if (!tr->tr_touched) {
                gfs2_log_release(sdp, tr->tr_reserved);
                gfs2_glock_dq(&tr->tr_t_gh);
                gfs2_holder_uninit(&tr->tr_t_gh);
                kfree(tr);
                return;
        }

        if (gfs2_assert_withdraw(sdp, tr->tr_num_buf <= tr->tr_blocks)) {
                fs_err(sdp, "tr_num_buf = %u, tr_blocks = %u ",
                       tr->tr_num_buf, tr->tr_blocks);
                print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
        }
        if (gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes)) {
                fs_err(sdp, "tr_num_revoke = %u, tr_revokes = %u ",
                       tr->tr_num_revoke, tr->tr_revokes);
                print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
        }

        gfs2_log_commit(sdp, tr);
        gfs2_glock_dq(&tr->tr_t_gh);
        gfs2_holder_uninit(&tr->tr_t_gh);
        kfree(tr);

        if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
                gfs2_log_flush(sdp, NULL);
}

/**
 * gfs2_trans_add_bh - Add a to-be-modified buffer to the current transaction
 * @gl: the glock the buffer belongs to
 * @bh: The buffer to add
 * @meta: True in the case of adding metadata
 *
 */

void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta)
{
        struct gfs2_sbd *sdp = gl->gl_sbd;
        struct gfs2_bufdata *bd;

        bd = bh->b_private;
        if (bd)
                gfs2_assert(sdp, bd->bd_gl == gl);
        else {
                gfs2_attach_bufdata(gl, bh, meta);
                bd = bh->b_private;
        }
        lops_add(sdp, &bd->bd_le);
}

void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
{
        BUG_ON(!list_empty(&bd->bd_le.le_list));
        BUG_ON(!list_empty(&bd->bd_ail_st_list));
        BUG_ON(!list_empty(&bd->bd_ail_gl_list));
        lops_init_le(&bd->bd_le, &gfs2_revoke_lops);
        lops_add(sdp, &bd->bd_le);
}

void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
{
        struct gfs2_bufdata *bd, *tmp;
        struct gfs2_trans *tr = current->journal_info;
        unsigned int n = len;

        gfs2_log_lock(sdp);
        list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_le.le_list) {
                if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
                        list_del_init(&bd->bd_le.le_list);
                        gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
                        sdp->sd_log_num_revoke--;
                        kmem_cache_free(gfs2_bufdata_cachep, bd);
                        tr->tr_num_revoke_rm++;
                        if (--n == 0)
                                break;
                }
        }
        gfs2_log_unlock(sdp);
}

void gfs2_trans_add_rg(struct gfs2_rgrpd *rgd)
{
        lops_add(rgd->rd_sbd, &rgd->rd_le);
}