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