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
  60         sb_start_intwrite(sdp->sd_vfs);
  61
  62         error = gfs2_log_reserve(sdp, tr->tr_reserved);
  63         if (error)
  64                 goto fail;
  65
  66         current->journal_info = tr;
  67
  68         return 0;
  69
  70 fail:
  71         sb_end_intwrite(sdp->sd_vfs);
  72         kfree(tr);
  73
  74         return error;
  75 }
  76
  77 static void gfs2_print_trans(const struct gfs2_trans *tr)
  78 {
  79         pr_warn("Transaction created at: %pSR\n", (void *)tr->tr_ip);
  80         pr_warn("blocks=%u revokes=%u reserved=%u touched=%u\n",
  81                 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
  82                 test_bit(TR_TOUCHED, &tr->tr_flags));
  83         pr_warn("Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
  84                 tr->tr_num_buf_new, tr->tr_num_buf_rm,
  85                 tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
  86                 tr->tr_num_revoke, tr->tr_num_revoke_rm);
  87 }
  88
  89 void gfs2_trans_end(struct gfs2_sbd *sdp)
  90 {
  91         struct gfs2_trans *tr = current->journal_info;
  92         s64 nbuf;
  93         int alloced = test_bit(TR_ALLOCED, &tr->tr_flags);
  94
  95         BUG_ON(!tr);
  96         current->journal_info = NULL;
  97
  98         if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
  99                 gfs2_log_release(sdp, tr->tr_reserved);
 100                 if (alloced) {
 101                         kfree(tr);
 102                         sb_end_intwrite(sdp->sd_vfs);
 103                 }
 104                 return;
 105         }
 106
 107         nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
 108         nbuf -= tr->tr_num_buf_rm;
 109         nbuf -= tr->tr_num_databuf_rm;
 110
 111         if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
 112                                        (tr->tr_num_revoke <= tr->tr_revokes)))
 113                 gfs2_print_trans(tr);
 114
 115         gfs2_log_commit(sdp, tr);
 116         if (alloced && !test_bit(TR_ATTACHED, &tr->tr_flags))
 117                 kfree(tr);
 118         up_read(&sdp->sd_log_flush_lock);
 119
 120         if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
 121                 gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
 122         if (alloced)
 123                 sb_end_intwrite(sdp->sd_vfs);
 124 }
 125
 126 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
 127                                                struct buffer_head *bh,
 128                                                const struct gfs2_log_operations *lops)
 129 {
 130         struct gfs2_bufdata *bd;
 131
 132         bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
 133         bd->bd_bh = bh;
 134         bd->bd_gl = gl;
 135         bd->bd_ops = lops;
 136         INIT_LIST_HEAD(&bd->bd_list);
 137         bh->b_private = bd;
 138         return bd;
 139 }
 140
 141 /**
 142  * gfs2_trans_add_data - Add a databuf to the transaction.
 143  * @gl: The inode glock associated with the buffer
 144  * @bh: The buffer to add
 145  *
 146  * This is used in two distinct cases:
 147  * i) In ordered write mode
 148  *    We put the data buffer on a list so that we can ensure that its
 149  *    synced to disk at the right time
 150  * ii) In journaled data mode
 151  *    We need to journal the data block in the same way as metadata in
 152  *    the functions above. The difference is that here we have a tag
 153  *    which is two __be64's being the block number (as per meta data)
 154  *    and a flag which says whether the data block needs escaping or
 155  *    not. This means we need a new log entry for each 251 or so data
 156  *    blocks, which isn't an enormous overhead but twice as much as
 157  *    for normal metadata blocks.
 158  */
 159 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
 160 {
 161         struct gfs2_trans *tr = current->journal_info;
 162         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 163         struct address_space *mapping = bh->b_page->mapping;
 164         struct gfs2_inode *ip = GFS2_I(mapping->host);
 165         struct gfs2_bufdata *bd;
 166
 167         if (!gfs2_is_jdata(ip)) {
 168                 gfs2_ordered_add_inode(ip);
 169                 return;
 170         }
 171
 172         lock_buffer(bh);
 173         if (buffer_pinned(bh)) {
 174                 set_bit(TR_TOUCHED, &tr->tr_flags);
 175                 goto out;
 176         }
 177         gfs2_log_lock(sdp);
 178         bd = bh->b_private;
 179         if (bd == NULL) {
 180                 gfs2_log_unlock(sdp);
 181                 unlock_buffer(bh);
 182                 if (bh->b_private == NULL)
 183                         bd = gfs2_alloc_bufdata(gl, bh, &gfs2_databuf_lops);
 184                 else
 185                         bd = bh->b_private;
 186                 lock_buffer(bh);
 187                 gfs2_log_lock(sdp);
 188         }
 189         gfs2_assert(sdp, bd->bd_gl == gl);
 190         set_bit(TR_TOUCHED, &tr->tr_flags);
 191         if (list_empty(&bd->bd_list)) {
 192                 set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 193                 set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 194                 gfs2_pin(sdp, bd->bd_bh);
 195                 tr->tr_num_databuf_new++;
 196                 list_add_tail(&bd->bd_list, &tr->tr_databuf);
 197         }
 198         gfs2_log_unlock(sdp);
 199 out:
 200         unlock_buffer(bh);
 201 }
 202
 203 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
 204 {
 205
 206         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 207         struct gfs2_bufdata *bd;
 208         struct gfs2_meta_header *mh;
 209         struct gfs2_trans *tr = current->journal_info;
 210         enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
 211
 212         lock_buffer(bh);
 213         if (buffer_pinned(bh)) {
 214                 set_bit(TR_TOUCHED, &tr->tr_flags);
 215                 goto out;
 216         }
 217         gfs2_log_lock(sdp);
 218         bd = bh->b_private;
 219         if (bd == NULL) {
 220                 gfs2_log_unlock(sdp);
 221                 unlock_buffer(bh);
 222                 lock_page(bh->b_page);
 223                 if (bh->b_private == NULL)
 224                         bd = gfs2_alloc_bufdata(gl, bh, &gfs2_buf_lops);
 225                 else
 226                         bd = bh->b_private;
 227                 unlock_page(bh->b_page);
 228                 lock_buffer(bh);
 229                 gfs2_log_lock(sdp);
 230         }
 231         gfs2_assert(sdp, bd->bd_gl == gl);
 232         set_bit(TR_TOUCHED, &tr->tr_flags);
 233         if (!list_empty(&bd->bd_list))
 234                 goto out_unlock;
 235         set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 236         set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 237         mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
 238         if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
 239                 pr_err("Attempting to add uninitialised block to journal (inplace block=%lld)\n",
 240                        (unsigned long long)bd->bd_bh->b_blocknr);
 241                 BUG();
 242         }
 243         if (unlikely(state == SFS_FROZEN)) {
 244                 printk(KERN_INFO "GFS2:adding buf while frozen\n");
 245                 gfs2_assert_withdraw(sdp, 0);
 246         }
 247         gfs2_pin(sdp, bd->bd_bh);
 248         mh->__pad0 = cpu_to_be64(0);
 249         mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
 250         list_add(&bd->bd_list, &tr->tr_buf);
 251         tr->tr_num_buf_new++;
 252 out_unlock:
 253         gfs2_log_unlock(sdp);
 254 out:
 255         unlock_buffer(bh);
 256 }
 257
 258 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 259 {
 260         struct gfs2_trans *tr = current->journal_info;
 261
 262         BUG_ON(!list_empty(&bd->bd_list));
 263         gfs2_add_revoke(sdp, bd);
 264         set_bit(TR_TOUCHED, &tr->tr_flags);
 265         tr->tr_num_revoke++;
 266 }
 267
 268 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
 269 {
 270         struct gfs2_bufdata *bd, *tmp;
 271         struct gfs2_trans *tr = current->journal_info;
 272         unsigned int n = len;
 273
 274         gfs2_log_lock(sdp);
 275         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) {
 276                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
 277                         list_del_init(&bd->bd_list);
 278                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
 279                         sdp->sd_log_num_revoke--;
 280                         kmem_cache_free(gfs2_bufdata_cachep, bd);
 281                         tr->tr_num_revoke_rm++;
 282                         if (--n == 0)
 283                                 break;
 284                 }
 285         }
 286         gfs2_log_unlock(sdp);
 287 }
 288