release/src-rt-6.x.4708/linux/linux-2.6.36/fs/gfs2/trans.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License version 2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/kallsyms.h>
  16 #include <linux/gfs2_ondisk.h>
  17
  18 #include "gfs2.h"
  19 #include "incore.h"
  20 #include "glock.h"
  21 #include "log.h"
  22 #include "lops.h"
  23 #include "meta_io.h"
  24 #include "trans.h"
  25 #include "util.h"
  26 #include "trace_gfs2.h"
  27
  28 int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
  29                      unsigned int revokes)
  30 {
  31         struct gfs2_trans *tr;
  32         int error;
  33
  34         BUG_ON(current->journal_info);
  35         BUG_ON(blocks == 0 && revokes == 0);
  36
  37         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
  38                 return -EROFS;
  39
  40         tr = kzalloc(sizeof(struct gfs2_trans), GFP_NOFS);
  41         if (!tr)
  42                 return -ENOMEM;
  43
  44         tr->tr_ip = (unsigned long)__builtin_return_address(0);
  45         tr->tr_blocks = blocks;
  46         tr->tr_revokes = revokes;
  47         tr->tr_reserved = 1;
  48         if (blocks)
  49                 tr->tr_reserved += 6 + blocks;
  50         if (revokes)
  51                 tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
  52                                                    sizeof(u64));
  53         INIT_LIST_HEAD(&tr->tr_list_buf);
  54
  55         gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh);
  56
  57         error = gfs2_glock_nq(&tr->tr_t_gh);
  58         if (error)
  59                 goto fail_holder_uninit;
  60
  61         error = gfs2_log_reserve(sdp, tr->tr_reserved);
  62         if (error)
  63                 goto fail_gunlock;
  64
  65         current->journal_info = tr;
  66
  67         return 0;
  68
  69 fail_gunlock:
  70         gfs2_glock_dq(&tr->tr_t_gh);
  71
  72 fail_holder_uninit:
  73         gfs2_holder_uninit(&tr->tr_t_gh);
  74         kfree(tr);
  75
  76         return error;
  77 }
  78
  79 /**
  80  * gfs2_log_release - Release a given number of log blocks
  81  * @sdp: The GFS2 superblock
  82  * @blks: The number of blocks
  83  *
  84  */
  85
  86 static void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
  87 {
  88
  89         atomic_add(blks, &sdp->sd_log_blks_free);
  90         trace_gfs2_log_blocks(sdp, blks);
  91         gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
  92                                   sdp->sd_jdesc->jd_blocks);
  93         up_read(&sdp->sd_log_flush_lock);
  94 }
  95
  96 void gfs2_trans_end(struct gfs2_sbd *sdp)
  97 {
  98         struct gfs2_trans *tr = current->journal_info;
  99
 100         BUG_ON(!tr);
 101         current->journal_info = NULL;
 102
 103         if (!tr->tr_touched) {
 104                 gfs2_log_release(sdp, tr->tr_reserved);
 105                 if (tr->tr_t_gh.gh_gl) {
 106                         gfs2_glock_dq(&tr->tr_t_gh);
 107                         gfs2_holder_uninit(&tr->tr_t_gh);
 108                         kfree(tr);
 109                 }
 110                 return;
 111         }
 112
 113         if (gfs2_assert_withdraw(sdp, tr->tr_num_buf <= tr->tr_blocks)) {
 114                 fs_err(sdp, "tr_num_buf = %u, tr_blocks = %u ",
 115                        tr->tr_num_buf, tr->tr_blocks);
 116                 print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
 117         }
 118         if (gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes)) {
 119                 fs_err(sdp, "tr_num_revoke = %u, tr_revokes = %u ",
 120                        tr->tr_num_revoke, tr->tr_revokes);
 121                 print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
 122         }
 123
 124         gfs2_log_commit(sdp, tr);
 125         if (tr->tr_t_gh.gh_gl) {
 126                 gfs2_glock_dq(&tr->tr_t_gh);
 127                 gfs2_holder_uninit(&tr->tr_t_gh);
 128                 kfree(tr);
 129         }
 130
 131         if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
 132                 gfs2_log_flush(sdp, NULL);
 133 }
 134
 135 /**
 136  * gfs2_trans_add_bh - Add a to-be-modified buffer to the current transaction
 137  * @gl: the glock the buffer belongs to
 138  * @bh: The buffer to add
 139  * @meta: True in the case of adding metadata
 140  *
 141  */
 142
 143 void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta)
 144 {
 145         struct gfs2_sbd *sdp = gl->gl_sbd;
 146         struct gfs2_bufdata *bd;
 147
 148         bd = bh->b_private;
 149         if (bd)
 150                 gfs2_assert(sdp, bd->bd_gl == gl);
 151         else {
 152                 gfs2_attach_bufdata(gl, bh, meta);
 153                 bd = bh->b_private;
 154         }
 155         lops_add(sdp, &bd->bd_le);
 156 }
 157
 158 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 159 {
 160         BUG_ON(!list_empty(&bd->bd_le.le_list));
 161         BUG_ON(!list_empty(&bd->bd_ail_st_list));
 162         BUG_ON(!list_empty(&bd->bd_ail_gl_list));
 163         lops_init_le(&bd->bd_le, &gfs2_revoke_lops);
 164         lops_add(sdp, &bd->bd_le);
 165 }
 166
 167 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
 168 {
 169         struct gfs2_bufdata *bd, *tmp;
 170         struct gfs2_trans *tr = current->journal_info;
 171         unsigned int n = len;
 172
 173         gfs2_log_lock(sdp);
 174         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_le.le_list) {
 175                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
 176                         list_del_init(&bd->bd_le.le_list);
 177                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
 178                         sdp->sd_log_num_revoke--;
 179                         kmem_cache_free(gfs2_bufdata_cachep, bd);
 180                         tr->tr_num_revoke_rm++;
 181                         if (--n == 0)
 182                                 break;
 183                 }
 184         }
 185         gfs2_log_unlock(sdp);
 186 }
 187
 188 void gfs2_trans_add_rg(struct gfs2_rgrpd *rgd)
 189 {
 190         lops_add(rgd->rd_sbd, &rgd->rd_le);
 191 }