sys/vfs/hammer/hammer_transaction.c

   1 /*
   2  * Copyright (c) 2007-2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/vfs/hammer/hammer_transaction.c,v 1.22 2008/06/26 04:06:23 dillon Exp $
  35  */
  36
  37 #include "hammer.h"
  38
  39 static hammer_tid_t hammer_alloc_tid(hammer_mount_t hmp, int count);
  40
  41
  42 /*
  43  * Start a standard transaction.
  44  */
  45 void
  46 hammer_start_transaction(struct hammer_transaction *trans,
  47                          struct hammer_mount *hmp)
  48 {
  49         struct timeval tv;
  50         int error;
  51
  52         trans->type = HAMMER_TRANS_STD;
  53         trans->hmp = hmp;
  54         trans->rootvol = hammer_get_root_volume(hmp, &error);
  55         KKASSERT(error == 0);
  56         trans->tid = 0;
  57         trans->sync_lock_refs = 0;
  58
  59         getmicrotime(&tv);
  60         trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
  61         trans->time32 = (u_int32_t)tv.tv_sec;
  62 }
  63
  64 /*
  65  * Start a simple read-only transaction.  This will not stall.
  66  */
  67 void
  68 hammer_simple_transaction(struct hammer_transaction *trans,
  69                           struct hammer_mount *hmp)
  70 {
  71         struct timeval tv;
  72         int error;
  73
  74         trans->type = HAMMER_TRANS_RO;
  75         trans->hmp = hmp;
  76         trans->rootvol = hammer_get_root_volume(hmp, &error);
  77         KKASSERT(error == 0);
  78         trans->tid = 0;
  79         trans->sync_lock_refs = 0;
  80
  81         getmicrotime(&tv);
  82         trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
  83         trans->time32 = (u_int32_t)tv.tv_sec;
  84 }
  85
  86 /*
  87  * Start a transaction using a particular TID.  Used by the sync code.
  88  * This does not stall.
  89  *
  90  * This routine may only be called from the flusher thread.  We predispose
  91  * sync_lock_refs, implying serialization against the synchronization stage
  92  * (which the flusher is responsible for).
  93  */
  94 void
  95 hammer_start_transaction_fls(struct hammer_transaction *trans,
  96                              struct hammer_mount *hmp)
  97 {
  98         struct timeval tv;
  99         int error;
 100
 101         bzero(trans, sizeof(*trans));
 102
 103         trans->type = HAMMER_TRANS_FLS;
 104         trans->hmp = hmp;
 105         trans->rootvol = hammer_get_root_volume(hmp, &error);
 106         KKASSERT(error == 0);
 107         trans->tid = hammer_alloc_tid(hmp, 1);
 108         trans->sync_lock_refs = 1;
 109
 110         getmicrotime(&tv);
 111         trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
 112         trans->time32 = (u_int32_t)tv.tv_sec;
 113 }
 114
 115 void
 116 hammer_done_transaction(struct hammer_transaction *trans)
 117 {
 118         int expected_lock_refs;
 119
 120         hammer_rel_volume(trans->rootvol, 0);
 121         trans->rootvol = NULL;
 122         expected_lock_refs = (trans->type == HAMMER_TRANS_FLS) ? 1 : 0;
 123         KKASSERT(trans->sync_lock_refs == expected_lock_refs);
 124         trans->sync_lock_refs = 0;
 125 }
 126
 127 /*
 128  * Allocate (count) TIDs.  If running in multi-master mode the returned
 129  * base will be aligned to a 16-count plus the master id (0-15).
 130  * Multi-master mode allows non-conflicting to run and new objects to be
 131  * created on multiple masters in parallel.  The transaction id identifies
 132  * the original master.  The object_id is also subject to this rule in
 133  * order to allow objects to be created on multiple masters in parallel.
 134  *
 135  * Directories may pre-allocate a large number of object ids (100,000).
 136  *
 137  * NOTE: There is no longer a requirement that successive transaction
 138  * ids be 2 apart for separator generation.
 139  */
 140 static hammer_tid_t
 141 hammer_alloc_tid(hammer_mount_t hmp, int count)
 142 {
 143         hammer_tid_t tid;
 144
 145         if (hmp->masterid < 0) {
 146                 tid = hmp->next_tid + 1;
 147                 hmp->next_tid = tid + count;
 148         } else {
 149                 tid = (hmp->next_tid + HAMMER_MAX_MASTERS) &
 150                       ~(hammer_tid_t)(HAMMER_MAX_MASTERS - 1);
 151                 hmp->next_tid = tid + count * HAMMER_MAX_MASTERS;
 152                 tid |= hmp->masterid;
 153         }
 154         if (tid >= 0xFFFFFFFFFF000000ULL)
 155                 panic("hammer_start_transaction: Ran out of TIDs!");
 156         if (hammer_debug_tid)
 157                 kprintf("alloc_tid %016llx\n", tid);
 158         return(tid);
 159 }
 160
 161 /*
 162  * Allocate an object id
 163  */
 164 hammer_tid_t
 165 hammer_alloc_objid(hammer_mount_t hmp, hammer_inode_t dip)
 166 {
 167         hammer_objid_cache_t ocp;
 168         hammer_tid_t tid;
 169
 170         while ((ocp = dip->objid_cache) == NULL) {
 171                 if (hmp->objid_cache_count < OBJID_CACHE_SIZE) {
 172                         ocp = kmalloc(sizeof(*ocp), M_HAMMER, M_WAITOK|M_ZERO);
 173                         ocp->next_tid = hammer_alloc_tid(hmp, OBJID_CACHE_BULK);
 174                         ocp->count = OBJID_CACHE_BULK;
 175                         TAILQ_INSERT_HEAD(&hmp->objid_cache_list, ocp, entry);
 176                         ++hmp->objid_cache_count;
 177                         /* may have blocked, recheck */
 178                         if (dip->objid_cache == NULL) {
 179                                 dip->objid_cache = ocp;
 180                                 ocp->dip = dip;
 181                         }
 182                 } else {
 183                         ocp = TAILQ_FIRST(&hmp->objid_cache_list);
 184                         if (ocp->dip)
 185                                 ocp->dip->objid_cache = NULL;
 186                         dip->objid_cache = ocp;
 187                         ocp->dip = dip;
 188                 }
 189         }
 190         TAILQ_REMOVE(&hmp->objid_cache_list, ocp, entry);
 191
 192         /*
 193          * The TID is incremented by 1 or by 16 depending what mode the
 194          * mount is operating in.
 195          */
 196         tid = ocp->next_tid;
 197         ocp->next_tid += (hmp->masterid < 0) ? 1 : HAMMER_MAX_MASTERS;
 198
 199         if (--ocp->count == 0) {
 200                 dip->objid_cache = NULL;
 201                 --hmp->objid_cache_count;
 202                 ocp->dip = NULL;
 203                 kfree(ocp, M_HAMMER);
 204         } else {
 205                 TAILQ_INSERT_TAIL(&hmp->objid_cache_list, ocp, entry);
 206         }
 207         return(tid);
 208 }
 209
 210 void
 211 hammer_clear_objid(hammer_inode_t dip)
 212 {
 213         hammer_objid_cache_t ocp;
 214
 215         if ((ocp = dip->objid_cache) != NULL) {
 216                 dip->objid_cache = NULL;
 217                 ocp->dip = NULL;
 218                 TAILQ_REMOVE(&dip->hmp->objid_cache_list, ocp, entry);
 219                 TAILQ_INSERT_HEAD(&dip->hmp->objid_cache_list, ocp, entry);
 220         }
 221 }
 222
 223 void
 224 hammer_destroy_objid_cache(hammer_mount_t hmp)
 225 {
 226         hammer_objid_cache_t ocp;
 227
 228         while ((ocp = TAILQ_FIRST(&hmp->objid_cache_list)) != NULL) {
 229                 TAILQ_REMOVE(&hmp->objid_cache_list, ocp, entry);
 230                 kfree(ocp, M_HAMMER);
 231         }
 232 }
 233