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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/sched.h>
  13 #include <linux/slab.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/completion.h>
  16 #include <linux/buffer_head.h>
  17 #include <linux/kallsyms.h>
  18 #include <linux/gfs2_ondisk.h>
  19
  20 #include "gfs2.h"
  21 #include "incore.h"
  22 #include "glock.h"
  23 #include "inode.h"
  24 #include "log.h"
  25 #include "lops.h"
  26 #include "meta_io.h"
  27 #include "trans.h"
  28 #include "util.h"
  29 #include "trace_gfs2.h"
  30
  31 int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
  32                      unsigned int revokes)
  33 {
  34         struct gfs2_trans *tr;
  35         int error;
  36
  37         BUG_ON(current->journal_info);
  38         BUG_ON(blocks == 0 && revokes == 0);
  39
  40         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
  41                 return -EROFS;
  42
  43         tr = kzalloc(sizeof(struct gfs2_trans), GFP_NOFS);
  44         if (!tr)
  45                 return -ENOMEM;
  46
  47         tr->tr_ip = _RET_IP_;
  48         tr->tr_blocks = blocks;
  49         tr->tr_revokes = revokes;
  50         tr->tr_reserved = 1;
  51         set_bit(TR_ALLOCED, &tr->tr_flags);
  52         if (blocks)
  53                 tr->tr_reserved += 6 + blocks;
  54         if (revokes)
  55                 tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
  56                                                    sizeof(u64));
  57         INIT_LIST_HEAD(&tr->tr_databuf);
  58         INIT_LIST_HEAD(&tr->tr_buf);
  59         INIT_LIST_HEAD(&tr->tr_ail1_list);
  60         INIT_LIST_HEAD(&tr->tr_ail2_list);
  61
  62         sb_start_intwrite(sdp->sd_vfs);
  63
  64         error = gfs2_log_reserve(sdp, tr->tr_reserved);
  65         if (error)
  66                 goto fail;
  67
  68         current->journal_info = tr;
  69
  70         return 0;
  71
  72 fail:
  73         sb_end_intwrite(sdp->sd_vfs);
  74         kfree(tr);
  75
  76         return error;
  77 }
  78
  79 static void gfs2_print_trans(const struct gfs2_trans *tr)
  80 {
  81         pr_warn("Transaction created at: %pSR\n", (void *)tr->tr_ip);
  82         pr_warn("blocks=%u revokes=%u reserved=%u touched=%u\n",
  83                 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
  84                 test_bit(TR_TOUCHED, &tr->tr_flags));
  85         pr_warn("Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
  86                 tr->tr_num_buf_new, tr->tr_num_buf_rm,
  87                 tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
  88                 tr->tr_num_revoke, tr->tr_num_revoke_rm);
  89 }
  90
  91 void gfs2_trans_end(struct gfs2_sbd *sdp)
  92 {
  93         struct gfs2_trans *tr = current->journal_info;
  94         s64 nbuf;
  95         int alloced = test_bit(TR_ALLOCED, &tr->tr_flags);
  96
  97         current->journal_info = NULL;
  98
  99         if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
 100                 gfs2_log_release(sdp, tr->tr_reserved);
 101                 if (alloced) {
 102                         kfree(tr);
 103                         sb_end_intwrite(sdp->sd_vfs);
 104                 }
 105                 return;
 106         }
 107
 108         nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
 109         nbuf -= tr->tr_num_buf_rm;
 110         nbuf -= tr->tr_num_databuf_rm;
 111
 112         if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
 113                                        (tr->tr_num_revoke <= tr->tr_revokes)))
 114                 gfs2_print_trans(tr);
 115
 116         gfs2_log_commit(sdp, tr);
 117         if (alloced && !test_bit(TR_ATTACHED, &tr->tr_flags))
 118                 kfree(tr);
 119         up_read(&sdp->sd_log_flush_lock);
 120
 121         if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
 122                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
 123                                GFS2_LFC_TRANS_END);
 124         if (alloced)
 125                 sb_end_intwrite(sdp->sd_vfs);
 126 }
 127
 128 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
 129                                                struct buffer_head *bh,
 130                                                const struct gfs2_log_operations *lops)
 131 {
 132         struct gfs2_bufdata *bd;
 133
 134         bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
 135         bd->bd_bh = bh;
 136         bd->bd_gl = gl;
 137         bd->bd_ops = lops;
 138         INIT_LIST_HEAD(&bd->bd_list);
 139         bh->b_private = bd;
 140         return bd;
 141 }
 142
 143 /**
 144  * gfs2_trans_add_data - Add a databuf to the transaction.
 145  * @gl: The inode glock associated with the buffer
 146  * @bh: The buffer to add
 147  *
 148  * This is used in journaled data mode.
 149  * We need to journal the data block in the same way as metadata in
 150  * the functions above. The difference is that here we have a tag
 151  * which is two __be64's being the block number (as per meta data)
 152  * and a flag which says whether the data block needs escaping or
 153  * not. This means we need a new log entry for each 251 or so data
 154  * blocks, which isn't an enormous overhead but twice as much as
 155  * for normal metadata blocks.
 156  */
 157 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
 158 {
 159         struct gfs2_trans *tr = current->journal_info;
 160         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 161         struct gfs2_bufdata *bd;
 162
 163         lock_buffer(bh);
 164         if (buffer_pinned(bh)) {
 165                 set_bit(TR_TOUCHED, &tr->tr_flags);
 166                 goto out;
 167         }
 168         gfs2_log_lock(sdp);
 169         bd = bh->b_private;
 170         if (bd == NULL) {
 171                 gfs2_log_unlock(sdp);
 172                 unlock_buffer(bh);
 173                 if (bh->b_private == NULL)
 174                         bd = gfs2_alloc_bufdata(gl, bh, &gfs2_databuf_lops);
 175                 else
 176                         bd = bh->b_private;
 177                 lock_buffer(bh);
 178                 gfs2_log_lock(sdp);
 179         }
 180         gfs2_assert(sdp, bd->bd_gl == gl);
 181         set_bit(TR_TOUCHED, &tr->tr_flags);
 182         if (list_empty(&bd->bd_list)) {
 183                 set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 184                 set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 185                 gfs2_pin(sdp, bd->bd_bh);
 186                 tr->tr_num_databuf_new++;
 187                 list_add_tail(&bd->bd_list, &tr->tr_databuf);
 188         }
 189         gfs2_log_unlock(sdp);
 190 out:
 191         unlock_buffer(bh);
 192 }
 193
 194 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
 195 {
 196
 197         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 198         struct gfs2_bufdata *bd;
 199         struct gfs2_meta_header *mh;
 200         struct gfs2_trans *tr = current->journal_info;
 201         enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
 202
 203         lock_buffer(bh);
 204         if (buffer_pinned(bh)) {
 205                 set_bit(TR_TOUCHED, &tr->tr_flags);
 206                 goto out;
 207         }
 208         gfs2_log_lock(sdp);
 209         bd = bh->b_private;
 210         if (bd == NULL) {
 211                 gfs2_log_unlock(sdp);
 212                 unlock_buffer(bh);
 213                 lock_page(bh->b_page);
 214                 if (bh->b_private == NULL)
 215                         bd = gfs2_alloc_bufdata(gl, bh, &gfs2_buf_lops);
 216                 else
 217                         bd = bh->b_private;
 218                 unlock_page(bh->b_page);
 219                 lock_buffer(bh);
 220                 gfs2_log_lock(sdp);
 221         }
 222         gfs2_assert(sdp, bd->bd_gl == gl);
 223         set_bit(TR_TOUCHED, &tr->tr_flags);
 224         if (!list_empty(&bd->bd_list))
 225                 goto out_unlock;
 226         set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 227         set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 228         mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
 229         if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
 230                 pr_err("Attempting to add uninitialised block to journal (inplace block=%lld)\n",
 231                        (unsigned long long)bd->bd_bh->b_blocknr);
 232                 BUG();
 233         }
 234         if (unlikely(state == SFS_FROZEN)) {
 235                 printk(KERN_INFO "GFS2:adding buf while frozen\n");
 236                 gfs2_assert_withdraw(sdp, 0);
 237         }
 238         gfs2_pin(sdp, bd->bd_bh);
 239         mh->__pad0 = cpu_to_be64(0);
 240         mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
 241         list_add(&bd->bd_list, &tr->tr_buf);
 242         tr->tr_num_buf_new++;
 243 out_unlock:
 244         gfs2_log_unlock(sdp);
 245 out:
 246         unlock_buffer(bh);
 247 }
 248
 249 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 250 {
 251         struct gfs2_trans *tr = current->journal_info;
 252
 253         BUG_ON(!list_empty(&bd->bd_list));
 254         gfs2_add_revoke(sdp, bd);
 255         set_bit(TR_TOUCHED, &tr->tr_flags);
 256         tr->tr_num_revoke++;
 257 }
 258
 259 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
 260 {
 261         struct gfs2_bufdata *bd, *tmp;
 262         struct gfs2_trans *tr = current->journal_info;
 263         unsigned int n = len;
 264
 265         gfs2_log_lock(sdp);
 266         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) {
 267                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
 268                         list_del_init(&bd->bd_list);
 269                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
 270                         sdp->sd_log_num_revoke--;
 271                         if (bd->bd_gl)
 272                                 gfs2_glock_remove_revoke(bd->bd_gl);
 273                         kmem_cache_free(gfs2_bufdata_cachep, bd);
 274                         tr->tr_num_revoke_rm++;
 275                         if (--n == 0)
 276                                 break;
 277                 }
 278         }
 279         gfs2_log_unlock(sdp);
 280 }
 281