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_default_mount_opts = ext2fs_swab32(sb->s_default_mount_opts);
  64         sb->s_first_meta_bg = ext2fs_swab32(sb->s_first_meta_bg);
  65         sb->s_mkfs_time = ext2fs_swab32(sb->s_mkfs_time);
  66         for (i=0; i < 4; i++)
  67                 sb->s_hash_seed[i] = ext2fs_swab32(sb->s_hash_seed[i]);
  68         for (i=0; i < 17; i++)
  69                 sb->s_jnl_blocks[i] = ext2fs_swab32(sb->s_jnl_blocks[i]);
  70
  71 }
  72
  73 void ext2fs_swap_group_desc(struct ext2_group_desc *gdp)
  74 {
  75         gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap);
  76         gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap);
  77         gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table);
  78         gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count);
  79         gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count);
  80         gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count);
  81         gdp->bg_flags = ext2fs_swab16(gdp->bg_flags);
  82 }
  83
  84 void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header)
  85 {
  86         struct ext2_ext_attr_header *from_header =
  87                 (struct ext2_ext_attr_header *)from;
  88         struct ext2_ext_attr_header *to_header =
  89                 (struct ext2_ext_attr_header *)to;
  90         struct ext2_ext_attr_entry *from_entry, *to_entry;
  91         char *from_end = (char *)from_header + bufsize;
  92         int n;
  93
  94         if (to_header != from_header)
  95                 memcpy(to_header, from_header, bufsize);
  96
  97         from_entry = (struct ext2_ext_attr_entry *)from_header;
  98         to_entry   = (struct ext2_ext_attr_entry *)to_header;
  99
 100         if (has_header) {
 101                 to_header->h_magic    = ext2fs_swab32(from_header->h_magic);
 102                 to_header->h_blocks   = ext2fs_swab32(from_header->h_blocks);
 103                 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
 104                 for (n=0; n<4; n++)
 105                         to_header->h_reserved[n] =
 106                                 ext2fs_swab32(from_header->h_reserved[n]);
 107                 from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
 108                 to_entry   = (struct ext2_ext_attr_entry *)(to_header+1);
 109         }
 110
 111         while ((char *)from_entry < from_end && *(__u32 *)from_entry) {
 112                 to_entry->e_value_offs  =
 113                         ext2fs_swab16(from_entry->e_value_offs);
 114                 to_entry->e_value_block =
 115                         ext2fs_swab32(from_entry->e_value_block);
 116                 to_entry->e_value_size  =
 117                         ext2fs_swab32(from_entry->e_value_size);
 118                 from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
 119                 to_entry   = EXT2_EXT_ATTR_NEXT(to_entry);
 120         }
 121 }
 122
 123 void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
 124                             struct ext2_inode_large *f, int hostorder,
 125                             int bufsize)
 126 {
 127         unsigned i;
 128         int islnk = 0;
 129         __u32 *eaf, *eat;
 130
 131         if (hostorder && LINUX_S_ISLNK(f->i_mode))
 132                 islnk = 1;
 133         t->i_mode = ext2fs_swab16(f->i_mode);
 134         if (!hostorder && LINUX_S_ISLNK(t->i_mode))
 135                 islnk = 1;
 136         t->i_uid = ext2fs_swab16(f->i_uid);
 137         t->i_size = ext2fs_swab32(f->i_size);
 138         t->i_atime = ext2fs_swab32(f->i_atime);
 139         t->i_ctime = ext2fs_swab32(f->i_ctime);
 140         t->i_mtime = ext2fs_swab32(f->i_mtime);
 141         t->i_dtime = ext2fs_swab32(f->i_dtime);
 142         t->i_gid = ext2fs_swab16(f->i_gid);
 143         t->i_links_count = ext2fs_swab16(f->i_links_count);
 144         t->i_blocks = ext2fs_swab32(f->i_blocks);
 145         t->i_flags = ext2fs_swab32(f->i_flags);
 146         t->i_file_acl = ext2fs_swab32(f->i_file_acl);
 147         t->i_dir_acl = ext2fs_swab32(f->i_dir_acl);
 148         if (!islnk || ext2fs_inode_data_blocks(fs, (struct ext2_inode *)t)) {
 149                 for (i = 0; i < EXT2_N_BLOCKS; i++)
 150                         t->i_block[i] = ext2fs_swab32(f->i_block[i]);
 151         } else if (t != f) {
 152                 for (i = 0; i < EXT2_N_BLOCKS; i++)
 153                         t->i_block[i] = f->i_block[i];
 154         }
 155         t->i_generation = ext2fs_swab32(f->i_generation);
 156         t->i_faddr = ext2fs_swab32(f->i_faddr);
 157
 158         switch (fs->super->s_creator_os) {
 159         case EXT2_OS_LINUX:
 160                 t->osd1.linux1.l_i_reserved1 =
 161                         ext2fs_swab32(f->osd1.linux1.l_i_reserved1);
 162                 t->osd2.linux2.l_i_frag = f->osd2.linux2.l_i_frag;
 163                 t->osd2.linux2.l_i_fsize = f->osd2.linux2.l_i_fsize;
 164                 t->osd2.linux2.i_pad1 = ext2fs_swab16(f->osd2.linux2.i_pad1);
 165                 t->osd2.linux2.l_i_uid_high =
 166                   ext2fs_swab16 (f->osd2.linux2.l_i_uid_high);
 167                 t->osd2.linux2.l_i_gid_high =
 168                   ext2fs_swab16 (f->osd2.linux2.l_i_gid_high);
 169                 t->osd2.linux2.l_i_reserved2 =
 170                         ext2fs_swab32(f->osd2.linux2.l_i_reserved2);
 171                 break;
 172         case EXT2_OS_HURD:
 173                 t->osd1.hurd1.h_i_translator =
 174                   ext2fs_swab32 (f->osd1.hurd1.h_i_translator);
 175                 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag;
 176                 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize;
 177                 t->osd2.hurd2.h_i_mode_high =
 178                   ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high);
 179                 t->osd2.hurd2.h_i_uid_high =
 180                   ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high);
 181                 t->osd2.hurd2.h_i_gid_high =
 182                   ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high);
 183                 t->osd2.hurd2.h_i_author =
 184                   ext2fs_swab32 (f->osd2.hurd2.h_i_author);
 185                 break;
 186         case EXT2_OS_MASIX:
 187                 t->osd1.masix1.m_i_reserved1 =
 188                         ext2fs_swab32(f->osd1.masix1.m_i_reserved1);
 189                 t->osd2.masix2.m_i_frag = f->osd2.masix2.m_i_frag;
 190                 t->osd2.masix2.m_i_fsize = f->osd2.masix2.m_i_fsize;
 191                 t->osd2.masix2.m_pad1 = ext2fs_swab16(f->osd2.masix2.m_pad1);
 192                 t->osd2.masix2.m_i_reserved2[0] =
 193                         ext2fs_swab32(f->osd2.masix2.m_i_reserved2[0]);
 194                 t->osd2.masix2.m_i_reserved2[1] =
 195                         ext2fs_swab32(f->osd2.masix2.m_i_reserved2[1]);
 196                 break;
 197         }
 198
 199         if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
 200                 return; /* no i_extra_isize field */
 201
 202         t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
 203         if (t->i_extra_isize > EXT2_INODE_SIZE(fs->super) -
 204                                 sizeof(struct ext2_inode)) {
 205                 /* this is error case: i_extra_size is too large */
 206                 return;
 207         }
 208
 209         i = sizeof(struct ext2_inode) + t->i_extra_isize + sizeof(__u32);
 210         if (bufsize < (int) i)
 211                 return; /* no space for EA magic */
 212
 213         eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
 214                                         f->i_extra_isize);
 215
 216         if (ext2fs_swab32(*eaf) != EXT2_EXT_ATTR_MAGIC)
 217                 return; /* it seems no magic here */
 218
 219         eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
 220                                         f->i_extra_isize);
 221         *eat = ext2fs_swab32(*eaf);
 222
 223         /* convert EA(s) */
 224         ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
 225                              bufsize - sizeof(struct ext2_inode) -
 226                              t->i_extra_isize - sizeof(__u32), 0);
 227
 228 }
 229
 230 void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t,
 231                        struct ext2_inode *f, int hostorder)
 232 {
 233         ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t,
 234                                 (struct ext2_inode_large *) f, hostorder,
 235                                 sizeof(struct ext2_inode));
 236 }
 237
 238 #endif