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         sb_start_intwrite(sdp->sd_vfs);
  54         gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh);
  55
  56         error = gfs2_glock_nq(&tr->tr_t_gh);
  57         if (error)
  58                 goto fail_holder_uninit;
  59
  60         error = gfs2_log_reserve(sdp, tr->tr_reserved);
  61         if (error)
  62                 goto fail_gunlock;
  63
  64         current->journal_info = tr;
  65
  66         return 0;
  67
  68 fail_gunlock:
  69         gfs2_glock_dq(&tr->tr_t_gh);
  70
  71 fail_holder_uninit:
  72         sb_end_intwrite(sdp->sd_vfs);
  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 static void gfs2_print_trans(const struct gfs2_trans *tr)
  97 {
  98         print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
  99         printk(KERN_WARNING "GFS2: blocks=%u revokes=%u reserved=%u touched=%d\n",
 100                tr->tr_blocks, tr->tr_revokes, tr->tr_reserved, tr->tr_touched);
 101         printk(KERN_WARNING "GFS2: Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
 102                tr->tr_num_buf_new, tr->tr_num_buf_rm,
 103                tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
 104                tr->tr_num_revoke, tr->tr_num_revoke_rm);
 105 }
 106
 107 void gfs2_trans_end(struct gfs2_sbd *sdp)
 108 {
 109         struct gfs2_trans *tr = current->journal_info;
 110         s64 nbuf;
 111         BUG_ON(!tr);
 112         current->journal_info = NULL;
 113
 114         if (!tr->tr_touched) {
 115                 gfs2_log_release(sdp, tr->tr_reserved);
 116                 if (tr->tr_t_gh.gh_gl) {
 117                         gfs2_glock_dq(&tr->tr_t_gh);
 118                         gfs2_holder_uninit(&tr->tr_t_gh);
 119                         kfree(tr);
 120                 }
 121                 sb_end_intwrite(sdp->sd_vfs);
 122                 return;
 123         }
 124
 125         nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
 126         nbuf -= tr->tr_num_buf_rm;
 127         nbuf -= tr->tr_num_databuf_rm;
 128
 129         if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
 130                                        (tr->tr_num_revoke <= tr->tr_revokes)))
 131                 gfs2_print_trans(tr);
 132
 133         gfs2_log_commit(sdp, tr);
 134         if (tr->tr_t_gh.gh_gl) {
 135                 gfs2_glock_dq(&tr->tr_t_gh);
 136                 gfs2_holder_uninit(&tr->tr_t_gh);
 137                 kfree(tr);
 138         }
 139
 140         if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
 141                 gfs2_log_flush(sdp, NULL);
 142         sb_end_intwrite(sdp->sd_vfs);
 143 }
 144
 145 /**
 146  * gfs2_trans_add_bh - Add a to-be-modified buffer to the current transaction
 147  * @gl: the glock the buffer belongs to
 148  * @bh: The buffer to add
 149  * @meta: True in the case of adding metadata
 150  *
 151  */
 152
 153 void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta)
 154 {
 155         struct gfs2_sbd *sdp = gl->gl_sbd;
 156         struct gfs2_bufdata *bd;
 157
 158         bd = bh->b_private;
 159         if (bd)
 160                 gfs2_assert(sdp, bd->bd_gl == gl);
 161         else {
 162                 gfs2_attach_bufdata(gl, bh, meta);
 163                 bd = bh->b_private;
 164         }
 165         lops_add(sdp, bd);
 166 }
 167
 168 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 169 {
 170         BUG_ON(!list_empty(&bd->bd_list));
 171         BUG_ON(!list_empty(&bd->bd_ail_st_list));
 172         BUG_ON(!list_empty(&bd->bd_ail_gl_list));
 173         lops_init_le(bd, &gfs2_revoke_lops);
 174         lops_add(sdp, bd);
 175 }
 176
 177 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
 178 {
 179         struct gfs2_bufdata *bd, *tmp;
 180         struct gfs2_trans *tr = current->journal_info;
 181         unsigned int n = len;
 182
 183         gfs2_log_lock(sdp);
 184         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) {
 185                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
 186                         list_del_init(&bd->bd_list);
 187                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
 188                         sdp->sd_log_num_revoke--;
 189                         kmem_cache_free(gfs2_bufdata_cachep, bd);
 190                         tr->tr_num_revoke_rm++;
 191                         if (--n == 0)
 192                                 break;
 193                 }
 194         }
 195         gfs2_log_unlock(sdp);
 196 }
 197