fs/gfs2/trans.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   5  */
   6
   7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   8
   9 #include <linux/sched.h>
  10 #include <linux/slab.h>
  11 #include <linux/spinlock.h>
  12 #include <linux/completion.h>
  13 #include <linux/buffer_head.h>
  14 #include <linux/kallsyms.h>
  15 #include <linux/gfs2_ondisk.h>
  16
  17 #include "gfs2.h"
  18 #include "incore.h"
  19 #include "glock.h"
  20 #include "inode.h"
  21 #include "log.h"
  22 #include "lops.h"
  23 #include "meta_io.h"
  24 #include "trans.h"
  25 #include "util.h"
  26 #include "trace_gfs2.h"
  27
  28 static void gfs2_print_trans(struct gfs2_sbd *sdp, const struct gfs2_trans *tr)
  29 {
  30         fs_warn(sdp, "Transaction created at: %pSR\n", (void *)tr->tr_ip);
  31         fs_warn(sdp, "blocks=%u revokes=%u reserved=%u touched=%u\n",
  32                 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
  33                 test_bit(TR_TOUCHED, &tr->tr_flags));
  34         fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u\n",
  35                 tr->tr_num_buf_new, tr->tr_num_buf_rm,
  36                 tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
  37                 tr->tr_num_revoke);
  38 }
  39
  40 int __gfs2_trans_begin(struct gfs2_trans *tr, struct gfs2_sbd *sdp,
  41                        unsigned int blocks, unsigned int revokes,
  42                        unsigned long ip)
  43 {
  44         unsigned int extra_revokes;
  45
  46         if (current->journal_info) {
  47                 gfs2_print_trans(sdp, current->journal_info);
  48                 BUG();
  49         }
  50         BUG_ON(blocks == 0 && revokes == 0);
  51
  52         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
  53                 return -EROFS;
  54
  55         tr->tr_ip = ip;
  56         tr->tr_blocks = blocks;
  57         tr->tr_revokes = revokes;
  58         tr->tr_reserved = GFS2_LOG_FLUSH_MIN_BLOCKS;
  59         if (blocks) {
  60                 /*
  61                  * The reserved blocks are either used for data or metadata.
  62                  * We can have mixed data and metadata, each with its own log
  63                  * descriptor block; see calc_reserved().
  64                  */
  65                 tr->tr_reserved += blocks + 1 + DIV_ROUND_UP(blocks - 1, databuf_limit(sdp));
  66         }
  67         INIT_LIST_HEAD(&tr->tr_databuf);
  68         INIT_LIST_HEAD(&tr->tr_buf);
  69         INIT_LIST_HEAD(&tr->tr_list);
  70         INIT_LIST_HEAD(&tr->tr_ail1_list);
  71         INIT_LIST_HEAD(&tr->tr_ail2_list);
  72
  73         if (gfs2_assert_warn(sdp, tr->tr_reserved <= sdp->sd_jdesc->jd_blocks))
  74                 return -EINVAL;
  75
  76         sb_start_intwrite(sdp->sd_vfs);
  77
  78         /*
  79          * Try the reservations under sd_log_flush_lock to prevent log flushes
  80          * from creating inconsistencies between the number of allocated and
  81          * reserved revokes.  If that fails, do a full-block allocation outside
  82          * of the lock to avoid stalling log flushes.  Then, allot the
  83          * appropriate number of blocks to revokes, use as many revokes locally
  84          * as needed, and "release" the surplus into the revokes pool.
  85          */
  86
  87         down_read(&sdp->sd_log_flush_lock);
  88         if (gfs2_log_try_reserve(sdp, tr, &extra_revokes))
  89                 goto reserved;
  90         up_read(&sdp->sd_log_flush_lock);
  91         gfs2_log_reserve(sdp, tr, &extra_revokes);
  92         down_read(&sdp->sd_log_flush_lock);
  93
  94 reserved:
  95         gfs2_log_release_revokes(sdp, extra_revokes);
  96         if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) {
  97                 gfs2_log_release_revokes(sdp, tr->tr_revokes);
  98                 up_read(&sdp->sd_log_flush_lock);
  99                 gfs2_log_release(sdp, tr->tr_reserved);
 100                 sb_end_intwrite(sdp->sd_vfs);
 101                 return -EROFS;
 102         }
 103
 104         current->journal_info = tr;
 105
 106         return 0;
 107 }
 108
 109 int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
 110                      unsigned int revokes)
 111 {
 112         struct gfs2_trans *tr;
 113         int error;
 114
 115         tr = kmem_cache_zalloc(gfs2_trans_cachep, GFP_NOFS);
 116         if (!tr)
 117                 return -ENOMEM;
 118         error = __gfs2_trans_begin(tr, sdp, blocks, revokes, _RET_IP_);
 119         if (error)
 120                 kmem_cache_free(gfs2_trans_cachep, tr);
 121         return error;
 122 }
 123
 124 void gfs2_trans_end(struct gfs2_sbd *sdp)
 125 {
 126         struct gfs2_trans *tr = current->journal_info;
 127         s64 nbuf;
 128
 129         current->journal_info = NULL;
 130
 131         if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
 132                 gfs2_log_release_revokes(sdp, tr->tr_revokes);
 133                 up_read(&sdp->sd_log_flush_lock);
 134                 gfs2_log_release(sdp, tr->tr_reserved);
 135                 if (!test_bit(TR_ONSTACK, &tr->tr_flags))
 136                         gfs2_trans_free(sdp, tr);
 137                 sb_end_intwrite(sdp->sd_vfs);
 138                 return;
 139         }
 140
 141         gfs2_log_release_revokes(sdp, tr->tr_revokes - tr->tr_num_revoke);
 142
 143         nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
 144         nbuf -= tr->tr_num_buf_rm;
 145         nbuf -= tr->tr_num_databuf_rm;
 146
 147         if (gfs2_assert_withdraw(sdp, nbuf <= tr->tr_blocks) ||
 148             gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes))
 149                 gfs2_print_trans(sdp, tr);
 150
 151         gfs2_log_commit(sdp, tr);
 152         if (!test_bit(TR_ONSTACK, &tr->tr_flags) &&
 153             !test_bit(TR_ATTACHED, &tr->tr_flags))
 154                 gfs2_trans_free(sdp, tr);
 155         up_read(&sdp->sd_log_flush_lock);
 156
 157         if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
 158                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
 159                                GFS2_LFC_TRANS_END);
 160         sb_end_intwrite(sdp->sd_vfs);
 161 }
 162
 163 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
 164                                                struct buffer_head *bh)
 165 {
 166         struct gfs2_bufdata *bd;
 167
 168         bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
 169         bd->bd_bh = bh;
 170         bd->bd_gl = gl;
 171         INIT_LIST_HEAD(&bd->bd_list);
 172         INIT_LIST_HEAD(&bd->bd_ail_st_list);
 173         INIT_LIST_HEAD(&bd->bd_ail_gl_list);
 174         bh->b_private = bd;
 175         return bd;
 176 }
 177
 178 /**
 179  * gfs2_trans_add_data - Add a databuf to the transaction.
 180  * @gl: The inode glock associated with the buffer
 181  * @bh: The buffer to add
 182  *
 183  * This is used in journaled data mode.
 184  * We need to journal the data block in the same way as metadata in
 185  * the functions above. The difference is that here we have a tag
 186  * which is two __be64's being the block number (as per meta data)
 187  * and a flag which says whether the data block needs escaping or
 188  * not. This means we need a new log entry for each 251 or so data
 189  * blocks, which isn't an enormous overhead but twice as much as
 190  * for normal metadata blocks.
 191  */
 192 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
 193 {
 194         struct gfs2_trans *tr = current->journal_info;
 195         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 196         struct gfs2_bufdata *bd;
 197
 198         lock_buffer(bh);
 199         if (buffer_pinned(bh)) {
 200                 set_bit(TR_TOUCHED, &tr->tr_flags);
 201                 goto out;
 202         }
 203         gfs2_log_lock(sdp);
 204         bd = bh->b_private;
 205         if (bd == NULL) {
 206                 gfs2_log_unlock(sdp);
 207                 unlock_buffer(bh);
 208                 if (bh->b_private == NULL)
 209                         bd = gfs2_alloc_bufdata(gl, bh);
 210                 else
 211                         bd = bh->b_private;
 212                 lock_buffer(bh);
 213                 gfs2_log_lock(sdp);
 214         }
 215         gfs2_assert(sdp, bd->bd_gl == gl);
 216         set_bit(TR_TOUCHED, &tr->tr_flags);
 217         if (list_empty(&bd->bd_list)) {
 218                 set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 219                 set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 220                 gfs2_pin(sdp, bd->bd_bh);
 221                 tr->tr_num_databuf_new++;
 222                 list_add_tail(&bd->bd_list, &tr->tr_databuf);
 223         }
 224         gfs2_log_unlock(sdp);
 225 out:
 226         unlock_buffer(bh);
 227 }
 228
 229 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
 230 {
 231
 232         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 233         struct super_block *sb = sdp->sd_vfs;
 234         struct gfs2_bufdata *bd;
 235         struct gfs2_meta_header *mh;
 236         struct gfs2_trans *tr = current->journal_info;
 237         bool withdraw = false;
 238
 239         lock_buffer(bh);
 240         if (buffer_pinned(bh)) {
 241                 set_bit(TR_TOUCHED, &tr->tr_flags);
 242                 goto out;
 243         }
 244         gfs2_log_lock(sdp);
 245         bd = bh->b_private;
 246         if (bd == NULL) {
 247                 gfs2_log_unlock(sdp);
 248                 unlock_buffer(bh);
 249                 lock_page(bh->b_page);
 250                 if (bh->b_private == NULL)
 251                         bd = gfs2_alloc_bufdata(gl, bh);
 252                 else
 253                         bd = bh->b_private;
 254                 unlock_page(bh->b_page);
 255                 lock_buffer(bh);
 256                 gfs2_log_lock(sdp);
 257         }
 258         gfs2_assert(sdp, bd->bd_gl == gl);
 259         set_bit(TR_TOUCHED, &tr->tr_flags);
 260         if (!list_empty(&bd->bd_list))
 261                 goto out_unlock;
 262         set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
 263         set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
 264         mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
 265         if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
 266                 fs_err(sdp, "Attempting to add uninitialised block to "
 267                        "journal (inplace block=%lld)\n",
 268                        (unsigned long long)bd->bd_bh->b_blocknr);
 269                 BUG();
 270         }
 271         if (unlikely(gfs2_withdrawn(sdp))) {
 272                 fs_info(sdp, "GFS2:adding buf while withdrawn! 0x%llx\n",
 273                         (unsigned long long)bd->bd_bh->b_blocknr);
 274                 goto out_unlock;
 275         }
 276         if (unlikely(sb->s_writers.frozen == SB_FREEZE_COMPLETE)) {
 277                 fs_info(sdp, "GFS2:adding buf while frozen\n");
 278                 withdraw = true;
 279                 goto out_unlock;
 280         }
 281         gfs2_pin(sdp, bd->bd_bh);
 282         mh->__pad0 = cpu_to_be64(0);
 283         mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
 284         list_add(&bd->bd_list, &tr->tr_buf);
 285         tr->tr_num_buf_new++;
 286 out_unlock:
 287         gfs2_log_unlock(sdp);
 288         if (withdraw)
 289                 gfs2_assert_withdraw(sdp, 0);
 290 out:
 291         unlock_buffer(bh);
 292 }
 293
 294 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 295 {
 296         struct gfs2_trans *tr = current->journal_info;
 297
 298         BUG_ON(!list_empty(&bd->bd_list));
 299         gfs2_add_revoke(sdp, bd);
 300         set_bit(TR_TOUCHED, &tr->tr_flags);
 301         tr->tr_num_revoke++;
 302 }
 303
 304 void gfs2_trans_remove_revoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
 305 {
 306         struct gfs2_bufdata *bd, *tmp;
 307         unsigned int n = len;
 308
 309         gfs2_log_lock(sdp);
 310         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_revokes, bd_list) {
 311                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
 312                         list_del_init(&bd->bd_list);
 313                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
 314                         sdp->sd_log_num_revoke--;
 315                         if (bd->bd_gl)
 316                                 gfs2_glock_remove_revoke(bd->bd_gl);
 317                         kmem_cache_free(gfs2_bufdata_cachep, bd);
 318                         gfs2_log_release_revokes(sdp, 1);
 319                         if (--n == 0)
 320                                 break;
 321                 }
 322         }
 323         gfs2_log_unlock(sdp);
 324 }
 325
 326 void gfs2_trans_free(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 327 {
 328         if (tr == NULL)
 329                 return;
 330
 331         gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
 332         gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
 333         gfs2_assert_warn(sdp, list_empty(&tr->tr_databuf));
 334         gfs2_assert_warn(sdp, list_empty(&tr->tr_buf));
 335         kmem_cache_free(gfs2_trans_cachep, tr);
 336 }