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         tr->tr_alloced = 1;
  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, tr->tr_touched);
  82         pr_warn("Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
  83                 tr->tr_num_buf_new, tr->tr_num_buf_rm,
  84                 tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
  85                 tr->tr_num_revoke, tr->tr_num_revoke_rm);
  86 }
  87
  88 void gfs2_trans_end(struct gfs2_sbd *sdp)
  89 {
  90         struct gfs2_trans *tr = current->journal_info;
  91         s64 nbuf;
  92         int alloced = tr->tr_alloced;
  93
  94         BUG_ON(!tr);
  95         current->journal_info = NULL;
  96
  97         if (!tr->tr_touched) {
  98                 gfs2_log_release(sdp, tr->tr_reserved);
  99                 if (alloced) {
 100                         kfree(tr);
 101                         sb_end_intwrite(sdp->sd_vfs);
 102                 }
 103                 return;
 104         }
 105
 106         nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
 107         nbuf -= tr->tr_num_buf_rm;
 108         nbuf -= tr->tr_num_databuf_rm;
 109
 110         if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
 111                                        (tr->tr_num_revoke <= tr->tr_revokes)))
 112                 gfs2_print_trans(tr);
 113
 114         gfs2_log_commit(sdp, tr);
 115         if (alloced && !tr->tr_attached)
 116                         kfree(tr);
 117         up_read(&sdp->sd_log_flush_lock);
 118
 119         if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
 120                 gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
 121         if (alloced)
 122                 sb_end_intwrite(sdp->sd_vfs);
 123 }
 124
 125 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
 126                                                struct buffer_head *bh,
 127                                                const struct gfs2_log_operations *lops)
 128 {
 129         struct gfs2_bufdata *bd;
 130
 131         bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
 132         bd->bd_bh = bh;
 133         bd->bd_gl = gl;
 134         bd->bd_ops = lops;
 135         INIT_LIST_HEAD(&bd->bd_list);
 136         bh->b_private = bd;
 137         return bd;
 138 }
 139
 140 /**
 141  * gfs2_trans_add_data - Add a databuf to the transaction.
 142  * @gl: The inode glock associated with the buffer
 143  * @bh: The buffer to add
 144  *
 145  * This is used in two distinct cases:
 146  * i) In ordered write mode
 147  *    We put the data buffer on a list so that we can ensure that its
 148  *    synced to disk at the right time
 149  * ii) In journaled data mode
 150  *    We need to journal the data block in the same way as metadata in
 151  *    the functions above. The difference is that here we have a tag
 152  *    which is two __be64's being the block number (as per meta data)
 153  *    and a flag which says whether the data block needs escaping or
 154  *    not. This means we need a new log entry for each 251 or so data
 155  *    blocks, which isn't an enormous overhead but twice as much as
 156  *    for normal metadata blocks.
 157  */
 158 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
 159 {
 160         struct gfs2_trans *tr = current->journal_info;
 161         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 162         struct address_space *mapping = bh->b_page->mapping;
 163         struct gfs2_inode *ip = GFS2_I(mapping->host);
 164         struct gfs2_bufdata *bd;
 165
 166         if (!gfs2_is_jdata(ip)) {
 167                 gfs2_ordered_add_inode(ip);
 168                 return;
 169         }
 170
 171         lock_buffer(bh);
 172         gfs2_log_lock(sdp);
 173         bd = bh->b_private;
 174         if (bd == NULL) {
 175                 gfs2_log_unlock(sdp);
 176                 unlock_buffer(bh);
 177                 if (bh->b_private == NULL)
 178                         bd = gfs2_alloc_bufdata(gl, bh, &gfs2_databuf_lops);
 179                 else
 180                         bd = bh->b_private;
 181                 lock_buffer(bh);
 182                 gfs2_log_lock(sdp);
 183         }
 184         gfs2_assert(sdp, bd->bd_gl == gl);
 185         tr->tr_touched = 1;
 186         if (list_empty(&bd->bd_list)) {
 187                 set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 188                 set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 189                 gfs2_pin(sdp, bd->bd_bh);
 190                 tr->tr_num_databuf_new++;
 191                 list_add_tail(&bd->bd_list, &tr->tr_databuf);
 192         }
 193         gfs2_log_unlock(sdp);
 194         unlock_buffer(bh);
 195 }
 196
 197 static void meta_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 198 {
 199         struct gfs2_meta_header *mh;
 200         struct gfs2_trans *tr;
 201         enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
 202
 203         tr = current->journal_info;
 204         tr->tr_touched = 1;
 205         if (!list_empty(&bd->bd_list))
 206                 return;
 207         set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 208         set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 209         mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
 210         if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
 211                 pr_err("Attempting to add uninitialised block to journal (inplace block=%lld)\n",
 212                        (unsigned long long)bd->bd_bh->b_blocknr);
 213                 BUG();
 214         }
 215         if (unlikely(state == SFS_FROZEN)) {
 216                 printk(KERN_INFO "GFS2:adding buf while frozen\n");
 217                 gfs2_assert_withdraw(sdp, 0);
 218         }
 219         gfs2_pin(sdp, bd->bd_bh);
 220         mh->__pad0 = cpu_to_be64(0);
 221         mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
 222         list_add(&bd->bd_list, &tr->tr_buf);
 223         tr->tr_num_buf_new++;
 224 }
 225
 226 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
 227 {
 228
 229         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 230         struct gfs2_bufdata *bd;
 231
 232         lock_buffer(bh);
 233         gfs2_log_lock(sdp);
 234         bd = bh->b_private;
 235         if (bd == NULL) {
 236                 gfs2_log_unlock(sdp);
 237                 unlock_buffer(bh);
 238                 lock_page(bh->b_page);
 239                 if (bh->b_private == NULL)
 240                         bd = gfs2_alloc_bufdata(gl, bh, &gfs2_buf_lops);
 241                 else
 242                         bd = bh->b_private;
 243                 unlock_page(bh->b_page);
 244                 lock_buffer(bh);
 245                 gfs2_log_lock(sdp);
 246         }
 247         gfs2_assert(sdp, bd->bd_gl == gl);
 248         meta_lo_add(sdp, bd);
 249         gfs2_log_unlock(sdp);
 250         unlock_buffer(bh);
 251 }
 252
 253 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 254 {
 255         struct gfs2_trans *tr = current->journal_info;
 256
 257         BUG_ON(!list_empty(&bd->bd_list));
 258         gfs2_add_revoke(sdp, bd);
 259         tr->tr_touched = 1;
 260         tr->tr_num_revoke++;
 261 }
 262
 263 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
 264 {
 265         struct gfs2_bufdata *bd, *tmp;
 266         struct gfs2_trans *tr = current->journal_info;
 267         unsigned int n = len;
 268
 269         gfs2_log_lock(sdp);
 270         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) {
 271                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
 272                         list_del_init(&bd->bd_list);
 273                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
 274                         sdp->sd_log_num_revoke--;
 275                         kmem_cache_free(gfs2_bufdata_cachep, bd);
 276                         tr->tr_num_revoke_rm++;
 277                         if (--n == 0)
 278                                 break;
 279                 }
 280         }
 281         gfs2_log_unlock(sdp);
 282 }
 283