fs/xfs/xfs_trans_bmap.c

   1 /*
   2  * Copyright (C) 2016 Oracle.  All Rights Reserved.
   3  *
   4  * Author: Darrick J. Wong <darrick.wong@oracle.com>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it would be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write the Free Software Foundation,
  18  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
  19  */
  20 #include "xfs.h"
  21 #include "xfs_fs.h"
  22 #include "xfs_shared.h"
  23 #include "xfs_format.h"
  24 #include "xfs_log_format.h"
  25 #include "xfs_trans_resv.h"
  26 #include "xfs_mount.h"
  27 #include "xfs_defer.h"
  28 #include "xfs_trans.h"
  29 #include "xfs_trans_priv.h"
  30 #include "xfs_bmap_item.h"
  31 #include "xfs_alloc.h"
  32 #include "xfs_bmap.h"
  33 #include "xfs_inode.h"
  34
  35 /*
  36  * This routine is called to allocate a "bmap update done"
  37  * log item.
  38  */
  39 struct xfs_bud_log_item *
  40 xfs_trans_get_bud(
  41         struct xfs_trans                *tp,
  42         struct xfs_bui_log_item         *buip)
  43 {
  44         struct xfs_bud_log_item         *budp;
  45
  46         budp = xfs_bud_init(tp->t_mountp, buip);
  47         xfs_trans_add_item(tp, &budp->bud_item);
  48         return budp;
  49 }
  50
  51 /*
  52  * Finish an bmap update and log it to the BUD. Note that the
  53  * transaction is marked dirty regardless of whether the bmap update
  54  * succeeds or fails to support the BUI/BUD lifecycle rules.
  55  */
  56 int
  57 xfs_trans_log_finish_bmap_update(
  58         struct xfs_trans                *tp,
  59         struct xfs_bud_log_item         *budp,
  60         struct xfs_defer_ops            *dop,
  61         enum xfs_bmap_intent_type       type,
  62         struct xfs_inode                *ip,
  63         int                             whichfork,
  64         xfs_fileoff_t                   startoff,
  65         xfs_fsblock_t                   startblock,
  66         xfs_filblks_t                   *blockcount,
  67         xfs_exntst_t                    state)
  68 {
  69         int                             error;
  70
  71         error = xfs_bmap_finish_one(tp, dop, ip, type, whichfork, startoff,
  72                         startblock, blockcount, state);
  73
  74         /*
  75          * Mark the transaction dirty, even on error. This ensures the
  76          * transaction is aborted, which:
  77          *
  78          * 1.) releases the BUI and frees the BUD
  79          * 2.) shuts down the filesystem
  80          */
  81         tp->t_flags |= XFS_TRANS_DIRTY;
  82         budp->bud_item.li_desc->lid_flags |= XFS_LID_DIRTY;
  83
  84         return error;
  85 }
  86
  87 /* Sort bmap intents by inode. */
  88 static int
  89 xfs_bmap_update_diff_items(
  90         void                            *priv,
  91         struct list_head                *a,
  92         struct list_head                *b)
  93 {
  94         struct xfs_bmap_intent          *ba;
  95         struct xfs_bmap_intent          *bb;
  96
  97         ba = container_of(a, struct xfs_bmap_intent, bi_list);
  98         bb = container_of(b, struct xfs_bmap_intent, bi_list);
  99         return ba->bi_owner->i_ino - bb->bi_owner->i_ino;
 100 }
 101
 102 /* Get an BUI. */
 103 STATIC void *
 104 xfs_bmap_update_create_intent(
 105         struct xfs_trans                *tp,
 106         unsigned int                    count)
 107 {
 108         struct xfs_bui_log_item         *buip;
 109
 110         ASSERT(count == XFS_BUI_MAX_FAST_EXTENTS);
 111         ASSERT(tp != NULL);
 112
 113         buip = xfs_bui_init(tp->t_mountp);
 114         ASSERT(buip != NULL);
 115
 116         /*
 117          * Get a log_item_desc to point at the new item.
 118          */
 119         xfs_trans_add_item(tp, &buip->bui_item);
 120         return buip;
 121 }
 122
 123 /* Set the map extent flags for this mapping. */
 124 static void
 125 xfs_trans_set_bmap_flags(
 126         struct xfs_map_extent           *bmap,
 127         enum xfs_bmap_intent_type       type,
 128         int                             whichfork,
 129         xfs_exntst_t                    state)
 130 {
 131         bmap->me_flags = 0;
 132         switch (type) {
 133         case XFS_BMAP_MAP:
 134         case XFS_BMAP_UNMAP:
 135                 bmap->me_flags = type;
 136                 break;
 137         default:
 138                 ASSERT(0);
 139         }
 140         if (state == XFS_EXT_UNWRITTEN)
 141                 bmap->me_flags |= XFS_BMAP_EXTENT_UNWRITTEN;
 142         if (whichfork == XFS_ATTR_FORK)
 143                 bmap->me_flags |= XFS_BMAP_EXTENT_ATTR_FORK;
 144 }
 145
 146 /* Log bmap updates in the intent item. */
 147 STATIC void
 148 xfs_bmap_update_log_item(
 149         struct xfs_trans                *tp,
 150         void                            *intent,
 151         struct list_head                *item)
 152 {
 153         struct xfs_bui_log_item         *buip = intent;
 154         struct xfs_bmap_intent          *bmap;
 155         uint                            next_extent;
 156         struct xfs_map_extent           *map;
 157
 158         bmap = container_of(item, struct xfs_bmap_intent, bi_list);
 159
 160         tp->t_flags |= XFS_TRANS_DIRTY;
 161         buip->bui_item.li_desc->lid_flags |= XFS_LID_DIRTY;
 162
 163         /*
 164          * atomic_inc_return gives us the value after the increment;
 165          * we want to use it as an array index so we need to subtract 1 from
 166          * it.
 167          */
 168         next_extent = atomic_inc_return(&buip->bui_next_extent) - 1;
 169         ASSERT(next_extent < buip->bui_format.bui_nextents);
 170         map = &buip->bui_format.bui_extents[next_extent];
 171         map->me_owner = bmap->bi_owner->i_ino;
 172         map->me_startblock = bmap->bi_bmap.br_startblock;
 173         map->me_startoff = bmap->bi_bmap.br_startoff;
 174         map->me_len = bmap->bi_bmap.br_blockcount;
 175         xfs_trans_set_bmap_flags(map, bmap->bi_type, bmap->bi_whichfork,
 176                         bmap->bi_bmap.br_state);
 177 }
 178
 179 /* Get an BUD so we can process all the deferred rmap updates. */
 180 STATIC void *
 181 xfs_bmap_update_create_done(
 182         struct xfs_trans                *tp,
 183         void                            *intent,
 184         unsigned int                    count)
 185 {
 186         return xfs_trans_get_bud(tp, intent);
 187 }
 188
 189 /* Process a deferred rmap update. */
 190 STATIC int
 191 xfs_bmap_update_finish_item(
 192         struct xfs_trans                *tp,
 193         struct xfs_defer_ops            *dop,
 194         struct list_head                *item,
 195         void                            *done_item,
 196         void                            **state)
 197 {
 198         struct xfs_bmap_intent          *bmap;
 199         xfs_filblks_t                   count;
 200         int                             error;
 201
 202         bmap = container_of(item, struct xfs_bmap_intent, bi_list);
 203         count = bmap->bi_bmap.br_blockcount;
 204         error = xfs_trans_log_finish_bmap_update(tp, done_item, dop,
 205                         bmap->bi_type,
 206                         bmap->bi_owner, bmap->bi_whichfork,
 207                         bmap->bi_bmap.br_startoff,
 208                         bmap->bi_bmap.br_startblock,
 209                         &count,
 210                         bmap->bi_bmap.br_state);
 211         if (!error && count > 0) {
 212                 ASSERT(bmap->bi_type == XFS_BMAP_UNMAP);
 213                 bmap->bi_bmap.br_blockcount = count;
 214                 return -EAGAIN;
 215         }
 216         kmem_free(bmap);
 217         return error;
 218 }
 219
 220 /* Abort all pending BUIs. */
 221 STATIC void
 222 xfs_bmap_update_abort_intent(
 223         void                            *intent)
 224 {
 225         xfs_bui_release(intent);
 226 }
 227
 228 /* Cancel a deferred rmap update. */
 229 STATIC void
 230 xfs_bmap_update_cancel_item(
 231         struct list_head                *item)
 232 {
 233         struct xfs_bmap_intent          *bmap;
 234
 235         bmap = container_of(item, struct xfs_bmap_intent, bi_list);
 236         kmem_free(bmap);
 237 }
 238
 239 static const struct xfs_defer_op_type xfs_bmap_update_defer_type = {
 240         .type           = XFS_DEFER_OPS_TYPE_BMAP,
 241         .max_items      = XFS_BUI_MAX_FAST_EXTENTS,
 242         .diff_items     = xfs_bmap_update_diff_items,
 243         .create_intent  = xfs_bmap_update_create_intent,
 244         .abort_intent   = xfs_bmap_update_abort_intent,
 245         .log_item       = xfs_bmap_update_log_item,
 246         .create_done    = xfs_bmap_update_create_done,
 247         .finish_item    = xfs_bmap_update_finish_item,
 248         .cancel_item    = xfs_bmap_update_cancel_item,
 249 };
 250
 251 /* Register the deferred op type. */
 252 void
 253 xfs_bmap_update_init_defer_op(void)
 254 {
 255         xfs_defer_init_op_type(&xfs_bmap_update_defer_type);
 256 }