lib/ext2fs/swapfs.c

   1 /*
   2  * swapfs.c --- swap ext2 filesystem data structures
   3  *
   4  * Copyright (C) 1995, 1996, 2002 Theodore Ts'o.
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Public
   8  * License.
   9  * %End-Header%
  10  */
  11
  12 #include <stdio.h>
  13 #if HAVE_UNISTD_H
  14 #include <unistd.h>
  15 #endif
  16 #include <string.h>
  17 #include <time.h>
  18
  19 #include "ext2_fs.h"
  20 #include "ext2fs.h"
  21 #include <ext2fs/ext2_ext_attr.h>
  22
  23 #ifdef EXT2FS_ENABLE_SWAPFS
  24 void ext2fs_swap_super(struct ext2_super_block * sb)
  25 {
  26         int i;
  27         sb->s_inodes_count = ext2fs_swab32(sb->s_inodes_count);
  28         sb->s_blocks_count = ext2fs_swab32(sb->s_blocks_count);
  29         sb->s_r_blocks_count = ext2fs_swab32(sb->s_r_blocks_count);
  30         sb->s_free_blocks_count = ext2fs_swab32(sb->s_free_blocks_count);
  31         sb->s_free_inodes_count = ext2fs_swab32(sb->s_free_inodes_count);
  32         sb->s_first_data_block = ext2fs_swab32(sb->s_first_data_block);
  33         sb->s_log_block_size = ext2fs_swab32(sb->s_log_block_size);
  34         sb->s_log_frag_size = ext2fs_swab32(sb->s_log_frag_size);
  35         sb->s_blocks_per_group = ext2fs_swab32(sb->s_blocks_per_group);
  36         sb->s_frags_per_group = ext2fs_swab32(sb->s_frags_per_group);
  37         sb->s_inodes_per_group = ext2fs_swab32(sb->s_inodes_per_group);
  38         sb->s_mtime = ext2fs_swab32(sb->s_mtime);
  39         sb->s_wtime = ext2fs_swab32(sb->s_wtime);
  40         sb->s_mnt_count = ext2fs_swab16(sb->s_mnt_count);
  41         sb->s_max_mnt_count = ext2fs_swab16(sb->s_max_mnt_count);
  42         sb->s_magic = ext2fs_swab16(sb->s_magic);
  43         sb->s_state = ext2fs_swab16(sb->s_state);
  44         sb->s_errors = ext2fs_swab16(sb->s_errors);
  45         sb->s_minor_rev_level = ext2fs_swab16(sb->s_minor_rev_level);
  46         sb->s_lastcheck = ext2fs_swab32(sb->s_lastcheck);
  47         sb->s_checkinterval = ext2fs_swab32(sb->s_checkinterval);
  48         sb->s_creator_os = ext2fs_swab32(sb->s_creator_os);
  49         sb->s_rev_level = ext2fs_swab32(sb->s_rev_level);
  50         sb->s_def_resuid = ext2fs_swab16(sb->s_def_resuid);
  51         sb->s_def_resgid = ext2fs_swab16(sb->s_def_resgid);
  52         sb->s_first_ino = ext2fs_swab32(sb->s_first_ino);
  53         sb->s_inode_size = ext2fs_swab16(sb->s_inode_size);
  54         sb->s_block_group_nr = ext2fs_swab16(sb->s_block_group_nr);
  55         sb->s_feature_compat = ext2fs_swab32(sb->s_feature_compat);
  56         sb->s_feature_incompat = ext2fs_swab32(sb->s_feature_incompat);
  57         sb->s_feature_ro_compat = ext2fs_swab32(sb->s_feature_ro_compat);
  58         sb->s_algorithm_usage_bitmap = ext2fs_swab32(sb->s_algorithm_usage_bitmap);
  59         sb->s_reserved_gdt_blocks = ext2fs_swab16(sb->s_reserved_gdt_blocks);
  60         sb->s_journal_inum = ext2fs_swab32(sb->s_journal_inum);
  61         sb->s_journal_dev = ext2fs_swab32(sb->s_journal_dev);
  62         sb->s_last_orphan = ext2fs_swab32(sb->s_last_orphan);
  63         sb->s_desc_size = ext2fs_swab16(sb->s_desc_size);
  64         sb->s_default_mount_opts = ext2fs_swab32(sb->s_default_mount_opts);
  65         sb->s_first_meta_bg = ext2fs_swab32(sb->s_first_meta_bg);
  66         sb->s_mkfs_time = ext2fs_swab32(sb->s_mkfs_time);
  67         for (i=0; i < 4; i++)
  68                 sb->s_hash_seed[i] = ext2fs_swab32(sb->s_hash_seed[i]);
  69         for (i=0; i < 17; i++)
  70                 sb->s_jnl_blocks[i] = ext2fs_swab32(sb->s_jnl_blocks[i]);
  71
  72 }
  73
  74 void ext2fs_swap_group_desc(struct ext2_group_desc *gdp)
  75 {
  76         gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap);
  77         gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap);
  78         gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table);
  79         gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count);
  80         gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count);
  81         gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count);
  82         gdp->bg_flags = ext2fs_swab16(gdp->bg_flags);
  83         gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused);
  84         gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum);
  85 }
  86
  87 void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header)
  88 {
  89         struct ext2_ext_attr_header *from_header =
  90                 (struct ext2_ext_attr_header *)from;
  91         struct ext2_ext_attr_header *to_header =
  92                 (struct ext2_ext_attr_header *)to;
  93         struct ext2_ext_attr_entry *from_entry, *to_entry;
  94         char *from_end = (char *)from_header + bufsize;
  95         int n;
  96
  97         if (to_header != from_header)
  98                 memcpy(to_header, from_header, bufsize);
  99
 100         from_entry = (struct ext2_ext_attr_entry *)from_header;
 101         to_entry   = (struct ext2_ext_attr_entry *)to_header;
 102
 103         if (has_header) {
 104                 to_header->h_magic    = ext2fs_swab32(from_header->h_magic);
 105                 to_header->h_blocks   = ext2fs_swab32(from_header->h_blocks);
 106                 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
 107                 for (n=0; n<4; n++)
 108                         to_header->h_reserved[n] =
 109                                 ext2fs_swab32(from_header->h_reserved[n]);
 110                 from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
 111                 to_entry   = (struct ext2_ext_attr_entry *)(to_header+1);
 112         }
 113
 114         while ((char *)from_entry < from_end && *(__u32 *)from_entry) {
 115                 to_entry->e_value_offs  =
 116                         ext2fs_swab16(from_entry->e_value_offs);
 117                 to_entry->e_value_block =
 118                         ext2fs_swab32(from_entry->e_value_block);
 119                 to_entry->e_value_size  =
 120                         ext2fs_swab32(from_entry->e_value_size);
 121                 from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
 122                 to_entry   = EXT2_EXT_ATTR_NEXT(to_entry);
 123         }
 124 }
 125
 126 void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
 127                             struct ext2_inode_large *f, int hostorder,
 128                             int bufsize)
 129 {
 130         unsigned i;
 131         int islnk = 0;
 132         __u32 *eaf, *eat;
 133
 134         if (hostorder && LINUX_S_ISLNK(f->i_mode))
 135                 islnk = 1;
 136         t->i_mode = ext2fs_swab16(f->i_mode);
 137         if (!hostorder && LINUX_S_ISLNK(t->i_mode))
 138                 islnk = 1;
 139         t->i_uid = ext2fs_swab16(f->i_uid);
 140         t->i_size = ext2fs_swab32(f->i_size);
 141         t->i_atime = ext2fs_swab32(f->i_atime);
 142         t->i_ctime = ext2fs_swab32(f->i_ctime);
 143         t->i_mtime = ext2fs_swab32(f->i_mtime);
 144         t->i_dtime = ext2fs_swab32(f->i_dtime);
 145         t->i_gid = ext2fs_swab16(f->i_gid);
 146         t->i_links_count = ext2fs_swab16(f->i_links_count);
 147         t->i_blocks = ext2fs_swab32(f->i_blocks);
 148         t->i_flags = ext2fs_swab32(f->i_flags);
 149         t->i_file_acl = ext2fs_swab32(f->i_file_acl);
 150         t->i_dir_acl = ext2fs_swab32(f->i_dir_acl);
 151         if (!islnk || ext2fs_inode_data_blocks(fs, (struct ext2_inode *)t)) {
 152                 for (i = 0; i < EXT2_N_BLOCKS; i++)
 153                         t->i_block[i] = ext2fs_swab32(f->i_block[i]);
 154         } else if (t != f) {
 155                 for (i = 0; i < EXT2_N_BLOCKS; i++)
 156                         t->i_block[i] = f->i_block[i];
 157         }
 158         t->i_generation = ext2fs_swab32(f->i_generation);
 159         t->i_faddr = ext2fs_swab32(f->i_faddr);
 160
 161         switch (fs->super->s_creator_os) {
 162         case EXT2_OS_LINUX:
 163                 t->osd1.linux1.l_i_reserved1 =
 164                         ext2fs_swab32(f->osd1.linux1.l_i_reserved1);
 165                 t->osd2.linux2.l_i_blocks_hi =
 166                         ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi);
 167                 t->osd2.linux2.i_pad1 = ext2fs_swab16(f->osd2.linux2.i_pad1);
 168                 t->osd2.linux2.l_i_uid_high =
 169                   ext2fs_swab16 (f->osd2.linux2.l_i_uid_high);
 170                 t->osd2.linux2.l_i_gid_high =
 171                   ext2fs_swab16 (f->osd2.linux2.l_i_gid_high);
 172                 t->osd2.linux2.l_i_reserved2 =
 173                         ext2fs_swab32(f->osd2.linux2.l_i_reserved2);
 174                 break;
 175         case EXT2_OS_HURD:
 176                 t->osd1.hurd1.h_i_translator =
 177                   ext2fs_swab32 (f->osd1.hurd1.h_i_translator);
 178                 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag;
 179                 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize;
 180                 t->osd2.hurd2.h_i_mode_high =
 181                   ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high);
 182                 t->osd2.hurd2.h_i_uid_high =
 183                   ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high);
 184                 t->osd2.hurd2.h_i_gid_high =
 185                   ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high);
 186                 t->osd2.hurd2.h_i_author =
 187                   ext2fs_swab32 (f->osd2.hurd2.h_i_author);
 188                 break;
 189         case EXT2_OS_MASIX:
 190                 t->osd1.masix1.m_i_reserved1 =
 191                         ext2fs_swab32(f->osd1.masix1.m_i_reserved1);
 192                 t->osd2.masix2.m_i_frag = f->osd2.masix2.m_i_frag;
 193                 t->osd2.masix2.m_i_fsize = f->osd2.masix2.m_i_fsize;
 194                 t->osd2.masix2.m_pad1 = ext2fs_swab16(f->osd2.masix2.m_pad1);
 195                 t->osd2.masix2.m_i_reserved2[0] =
 196                         ext2fs_swab32(f->osd2.masix2.m_i_reserved2[0]);
 197                 t->osd2.masix2.m_i_reserved2[1] =
 198                         ext2fs_swab32(f->osd2.masix2.m_i_reserved2[1]);
 199                 break;
 200         }
 201
 202         if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
 203                 return; /* no i_extra_isize field */
 204
 205         t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
 206         if (t->i_extra_isize > EXT2_INODE_SIZE(fs->super) -
 207                                 sizeof(struct ext2_inode)) {
 208                 /* this is error case: i_extra_size is too large */
 209                 return;
 210         }
 211
 212         i = sizeof(struct ext2_inode) + t->i_extra_isize + sizeof(__u32);
 213         if (bufsize < (int) i)
 214                 return; /* no space for EA magic */
 215
 216         eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
 217                                         f->i_extra_isize);
 218
 219         if (ext2fs_swab32(*eaf) != EXT2_EXT_ATTR_MAGIC)
 220                 return; /* it seems no magic here */
 221
 222         eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
 223                                         f->i_extra_isize);
 224         *eat = ext2fs_swab32(*eaf);
 225
 226         /* convert EA(s) */
 227         ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
 228                              bufsize - sizeof(struct ext2_inode) -
 229                              t->i_extra_isize - sizeof(__u32), 0);
 230
 231 }
 232
 233 void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t,
 234                        struct ext2_inode *f, int hostorder)
 235 {
 236         ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t,
 237                                 (struct ext2_inode_large *) f, hostorder,
 238                                 sizeof(struct ext2_inode));
 239 }
 240
 241 #endif