fs/nilfs2/gcdat.c

   1 /*
   2  * gcdat.c - NILFS shadow DAT inode for GC
   3  *
   4  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will 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 to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  * Written by Seiji Kihara <kihara@osrg.net>, Amagai Yoshiji <amagai@osrg.net>,
  21  *            and Ryusuke Konishi <ryusuke@osrg.net>.
  22  *
  23  */
  24
  25 #include <linux/buffer_head.h>
  26 #include "nilfs.h"
  27 #include "page.h"
  28 #include "mdt.h"
  29
  30 int nilfs_init_gcdat_inode(struct the_nilfs *nilfs)
  31 {
  32         struct inode *dat = nilfs->ns_dat, *gcdat = nilfs->ns_gc_dat;
  33         struct nilfs_inode_info *dii = NILFS_I(dat), *gii = NILFS_I(gcdat);
  34         int err;
  35
  36         gcdat->i_state = 0;
  37         gcdat->i_blocks = dat->i_blocks;
  38         gii->i_flags = dii->i_flags;
  39         gii->i_state = dii->i_state | (1 << NILFS_I_GCDAT);
  40         gii->i_cno = 0;
  41         nilfs_bmap_init_gcdat(gii->i_bmap, dii->i_bmap);
  42         err = nilfs_copy_dirty_pages(gcdat->i_mapping, dat->i_mapping);
  43         if (unlikely(err))
  44                 return err;
  45
  46         return nilfs_copy_dirty_pages(&gii->i_btnode_cache,
  47                                       &dii->i_btnode_cache);
  48 }
  49
  50 void nilfs_commit_gcdat_inode(struct the_nilfs *nilfs)
  51 {
  52         struct inode *dat = nilfs->ns_dat, *gcdat = nilfs->ns_gc_dat;
  53         struct nilfs_inode_info *dii = NILFS_I(dat), *gii = NILFS_I(gcdat);
  54         struct address_space *mapping = dat->i_mapping;
  55         struct address_space *gmapping = gcdat->i_mapping;
  56
  57         down_write(&NILFS_MDT(dat)->mi_sem);
  58         dat->i_blocks = gcdat->i_blocks;
  59         dii->i_flags = gii->i_flags;
  60         dii->i_state = gii->i_state & ~(1 << NILFS_I_GCDAT);
  61
  62         nilfs_bmap_commit_gcdat(gii->i_bmap, dii->i_bmap);
  63
  64         nilfs_clear_dirty_pages(mapping);
  65         nilfs_copy_back_pages(mapping, gmapping);
  66         /* note: mdt dirty flags should be cleared by segctor. */
  67
  68         nilfs_clear_dirty_pages(&dii->i_btnode_cache);
  69         nilfs_copy_back_pages(&dii->i_btnode_cache, &gii->i_btnode_cache);
  70
  71         up_write(&NILFS_MDT(dat)->mi_sem);
  72 }
  73
  74 void nilfs_clear_gcdat_inode(struct the_nilfs *nilfs)
  75 {
  76         struct inode *gcdat = nilfs->ns_gc_dat;
  77         struct nilfs_inode_info *gii = NILFS_I(gcdat);
  78
  79         gcdat->i_state = I_CLEAR;
  80         gii->i_flags = 0;
  81
  82         truncate_inode_pages(gcdat->i_mapping, 0);
  83         truncate_inode_pages(&gii->i_btnode_cache, 0);
  84 }