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         if (blocks)
  52                 tr->tr_reserved += 6 + blocks;
  53         if (revokes)
  54                 tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
  55                                                    sizeof(u64));
  56         INIT_LIST_HEAD(&tr->tr_databuf);
  57         INIT_LIST_HEAD(&tr->tr_buf);
  58
  59         sb_start_intwrite(sdp->sd_vfs);
  60         gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh);
  61
  62         error = gfs2_glock_nq(&tr->tr_t_gh);
  63         if (error)
  64                 goto fail_holder_uninit;
  65
  66         error = gfs2_log_reserve(sdp, tr->tr_reserved);
  67         if (error)
  68                 goto fail_gunlock;
  69
  70         current->journal_info = tr;
  71
  72         return 0;
  73
  74 fail_gunlock:
  75         gfs2_glock_dq(&tr->tr_t_gh);
  76
  77 fail_holder_uninit:
  78         sb_end_intwrite(sdp->sd_vfs);
  79         gfs2_holder_uninit(&tr->tr_t_gh);
  80         kfree(tr);
  81
  82         return error;
  83 }
  84
  85 /**
  86  * gfs2_log_release - Release a given number of log blocks
  87  * @sdp: The GFS2 superblock
  88  * @blks: The number of blocks
  89  *
  90  */
  91
  92 static void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
  93 {
  94
  95         atomic_add(blks, &sdp->sd_log_blks_free);
  96         trace_gfs2_log_blocks(sdp, blks);
  97         gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
  98                                   sdp->sd_jdesc->jd_blocks);
  99         up_read(&sdp->sd_log_flush_lock);
 100 }
 101
 102 static void gfs2_print_trans(const struct gfs2_trans *tr)
 103 {
 104         pr_warn("Transaction created at: %pSR\n", (void *)tr->tr_ip);
 105         pr_warn("blocks=%u revokes=%u reserved=%u touched=%u\n",
 106                 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved, tr->tr_touched);
 107         pr_warn("Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
 108                 tr->tr_num_buf_new, tr->tr_num_buf_rm,
 109                 tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
 110                 tr->tr_num_revoke, tr->tr_num_revoke_rm);
 111 }
 112
 113 void gfs2_trans_end(struct gfs2_sbd *sdp)
 114 {
 115         struct gfs2_trans *tr = current->journal_info;
 116         s64 nbuf;
 117         BUG_ON(!tr);
 118         current->journal_info = NULL;
 119
 120         if (!tr->tr_touched) {
 121                 gfs2_log_release(sdp, tr->tr_reserved);
 122                 if (tr->tr_t_gh.gh_gl) {
 123                         gfs2_glock_dq(&tr->tr_t_gh);
 124                         gfs2_holder_uninit(&tr->tr_t_gh);
 125                         kfree(tr);
 126                 }
 127                 sb_end_intwrite(sdp->sd_vfs);
 128                 return;
 129         }
 130
 131         nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
 132         nbuf -= tr->tr_num_buf_rm;
 133         nbuf -= tr->tr_num_databuf_rm;
 134
 135         if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
 136                                        (tr->tr_num_revoke <= tr->tr_revokes)))
 137                 gfs2_print_trans(tr);
 138
 139         gfs2_log_commit(sdp, tr);
 140         if (tr->tr_t_gh.gh_gl) {
 141                 gfs2_glock_dq(&tr->tr_t_gh);
 142                 gfs2_holder_uninit(&tr->tr_t_gh);
 143                 if (!tr->tr_attached)
 144                         kfree(tr);
 145         }
 146         up_read(&sdp->sd_log_flush_lock);
 147
 148         if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
 149                 gfs2_log_flush(sdp, NULL);
 150         sb_end_intwrite(sdp->sd_vfs);
 151 }
 152
 153 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
 154                                                struct buffer_head *bh,
 155                                                const struct gfs2_log_operations *lops)
 156 {
 157         struct gfs2_bufdata *bd;
 158
 159         bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
 160         bd->bd_bh = bh;
 161         bd->bd_gl = gl;
 162         bd->bd_ops = lops;
 163         INIT_LIST_HEAD(&bd->bd_list);
 164         bh->b_private = bd;
 165         return bd;
 166 }
 167
 168 /**
 169  * gfs2_trans_add_data - Add a databuf to the transaction.
 170  * @gl: The inode glock associated with the buffer
 171  * @bh: The buffer to add
 172  *
 173  * This is used in two distinct cases:
 174  * i) In ordered write mode
 175  *    We put the data buffer on a list so that we can ensure that its
 176  *    synced to disk at the right time
 177  * ii) In journaled data mode
 178  *    We need to journal the data block in the same way as metadata in
 179  *    the functions above. The difference is that here we have a tag
 180  *    which is two __be64's being the block number (as per meta data)
 181  *    and a flag which says whether the data block needs escaping or
 182  *    not. This means we need a new log entry for each 251 or so data
 183  *    blocks, which isn't an enormous overhead but twice as much as
 184  *    for normal metadata blocks.
 185  */
 186 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
 187 {
 188         struct gfs2_trans *tr = current->journal_info;
 189         struct gfs2_sbd *sdp = gl->gl_sbd;
 190         struct address_space *mapping = bh->b_page->mapping;
 191         struct gfs2_inode *ip = GFS2_I(mapping->host);
 192         struct gfs2_bufdata *bd;
 193
 194         if (!gfs2_is_jdata(ip)) {
 195                 gfs2_ordered_add_inode(ip);
 196                 return;
 197         }
 198
 199         lock_buffer(bh);
 200         gfs2_log_lock(sdp);
 201         bd = bh->b_private;
 202         if (bd == NULL) {
 203                 gfs2_log_unlock(sdp);
 204                 unlock_buffer(bh);
 205                 if (bh->b_private == NULL)
 206                         bd = gfs2_alloc_bufdata(gl, bh, &gfs2_databuf_lops);
 207                 lock_buffer(bh);
 208                 gfs2_log_lock(sdp);
 209         }
 210         gfs2_assert(sdp, bd->bd_gl == gl);
 211         tr->tr_touched = 1;
 212         if (list_empty(&bd->bd_list)) {
 213                 set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 214                 set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 215                 gfs2_pin(sdp, bd->bd_bh);
 216                 tr->tr_num_databuf_new++;
 217                 list_add_tail(&bd->bd_list, &tr->tr_databuf);
 218         }
 219         gfs2_log_unlock(sdp);
 220         unlock_buffer(bh);
 221 }
 222
 223 static void meta_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 224 {
 225         struct gfs2_meta_header *mh;
 226         struct gfs2_trans *tr;
 227
 228         tr = current->journal_info;
 229         tr->tr_touched = 1;
 230         if (!list_empty(&bd->bd_list))
 231                 return;
 232         set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 233         set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 234         mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
 235         if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
 236                 pr_err("Attempting to add uninitialised block to journal (inplace block=%lld)\n",
 237                        (unsigned long long)bd->bd_bh->b_blocknr);
 238                 BUG();
 239         }
 240         gfs2_pin(sdp, bd->bd_bh);
 241         mh->__pad0 = cpu_to_be64(0);
 242         mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
 243         list_add(&bd->bd_list, &tr->tr_buf);
 244         tr->tr_num_buf_new++;
 245 }
 246
 247 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
 248 {
 249
 250         struct gfs2_sbd *sdp = gl->gl_sbd;
 251         struct gfs2_bufdata *bd;
 252
 253         lock_buffer(bh);
 254         gfs2_log_lock(sdp);
 255         bd = bh->b_private;
 256         if (bd == NULL) {
 257                 gfs2_log_unlock(sdp);
 258                 unlock_buffer(bh);
 259                 lock_page(bh->b_page);
 260                 if (bh->b_private == NULL)
 261                         bd = gfs2_alloc_bufdata(gl, bh, &gfs2_buf_lops);
 262                 unlock_page(bh->b_page);
 263                 lock_buffer(bh);
 264                 gfs2_log_lock(sdp);
 265         }
 266         gfs2_assert(sdp, bd->bd_gl == gl);
 267         meta_lo_add(sdp, bd);
 268         gfs2_log_unlock(sdp);
 269         unlock_buffer(bh);
 270 }
 271
 272 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 273 {
 274         struct gfs2_trans *tr = current->journal_info;
 275
 276         BUG_ON(!list_empty(&bd->bd_list));
 277         gfs2_add_revoke(sdp, bd);
 278         tr->tr_touched = 1;
 279         tr->tr_num_revoke++;
 280 }
 281
 282 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
 283 {
 284         struct gfs2_bufdata *bd, *tmp;
 285         struct gfs2_trans *tr = current->journal_info;
 286         unsigned int n = len;
 287
 288         gfs2_log_lock(sdp);
 289         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) {
 290                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
 291                         list_del_init(&bd->bd_list);
 292                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
 293                         sdp->sd_log_num_revoke--;
 294                         kmem_cache_free(gfs2_bufdata_cachep, bd);
 295                         tr->tr_num_revoke_rm++;
 296                         if (--n == 0)
 297                                 break;
 298                 }
 299         }
 300         gfs2_log_unlock(sdp);
 301 }
 302