swapfs.c revision c844010cc41e4c293b652d252145df12448e22c6
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
24void 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	sb->s_blocks_count_hi = ext2fs_swab32(sb->s_blocks_count_hi);
68	sb->s_r_blocks_count_hi = ext2fs_swab32(sb->s_r_blocks_count_hi);
69	sb->s_free_blocks_hi = ext2fs_swab32(sb->s_free_blocks_hi);
70	sb->s_min_extra_isize = ext2fs_swab16(sb->s_min_extra_isize);
71	sb->s_want_extra_isize = ext2fs_swab16(sb->s_want_extra_isize);
72	sb->s_flags = ext2fs_swab32(sb->s_flags);
73	for (i=0; i < 4; i++)
74		sb->s_hash_seed[i] = ext2fs_swab32(sb->s_hash_seed[i]);
75	for (i=0; i < 17; i++)
76		sb->s_jnl_blocks[i] = ext2fs_swab32(sb->s_jnl_blocks[i]);
77
78}
79
80void ext2fs_swap_group_desc(struct ext2_group_desc *gdp)
81{
82	gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap);
83	gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap);
84	gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table);
85	gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count);
86	gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count);
87	gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count);
88	gdp->bg_flags = ext2fs_swab16(gdp->bg_flags);
89	gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused);
90	gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum);
91}
92
93void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header)
94{
95	struct ext2_ext_attr_header *from_header =
96		(struct ext2_ext_attr_header *)from;
97	struct ext2_ext_attr_header *to_header =
98		(struct ext2_ext_attr_header *)to;
99	struct ext2_ext_attr_entry *from_entry, *to_entry;
100	char *from_end = (char *)from_header + bufsize;
101	int n;
102
103	if (to_header != from_header)
104		memcpy(to_header, from_header, bufsize);
105
106	from_entry = (struct ext2_ext_attr_entry *)from_header;
107	to_entry   = (struct ext2_ext_attr_entry *)to_header;
108
109	if (has_header) {
110		to_header->h_magic    = ext2fs_swab32(from_header->h_magic);
111		to_header->h_blocks   = ext2fs_swab32(from_header->h_blocks);
112		to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
113		for (n=0; n<4; n++)
114			to_header->h_reserved[n] =
115				ext2fs_swab32(from_header->h_reserved[n]);
116		from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
117		to_entry   = (struct ext2_ext_attr_entry *)(to_header+1);
118	}
119
120	while ((char *)from_entry < from_end && *(__u32 *)from_entry) {
121		to_entry->e_value_offs  =
122			ext2fs_swab16(from_entry->e_value_offs);
123		to_entry->e_value_block =
124			ext2fs_swab32(from_entry->e_value_block);
125		to_entry->e_value_size  =
126			ext2fs_swab32(from_entry->e_value_size);
127		from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
128		to_entry   = EXT2_EXT_ATTR_NEXT(to_entry);
129	}
130}
131
132void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
133			    struct ext2_inode_large *f, int hostorder,
134			    int bufsize)
135{
136	unsigned i, has_data_blocks, extra_isize;
137	int islnk = 0;
138	__u32 *eaf, *eat;
139
140	if (hostorder && LINUX_S_ISLNK(f->i_mode))
141		islnk = 1;
142	t->i_mode = ext2fs_swab16(f->i_mode);
143	if (!hostorder && LINUX_S_ISLNK(t->i_mode))
144		islnk = 1;
145	t->i_uid = ext2fs_swab16(f->i_uid);
146	t->i_size = ext2fs_swab32(f->i_size);
147	t->i_atime = ext2fs_swab32(f->i_atime);
148	t->i_ctime = ext2fs_swab32(f->i_ctime);
149	t->i_mtime = ext2fs_swab32(f->i_mtime);
150	t->i_dtime = ext2fs_swab32(f->i_dtime);
151	t->i_gid = ext2fs_swab16(f->i_gid);
152	t->i_links_count = ext2fs_swab16(f->i_links_count);
153	if (hostorder)
154		has_data_blocks = ext2fs_inode_data_blocks(fs,
155					   (struct ext2_inode *) f);
156	t->i_blocks = ext2fs_swab32(f->i_blocks);
157	if (!hostorder)
158		has_data_blocks = ext2fs_inode_data_blocks(fs,
159					   (struct ext2_inode *) t);
160	t->i_flags = ext2fs_swab32(f->i_flags);
161	t->i_file_acl = ext2fs_swab32(f->i_file_acl);
162	t->i_dir_acl = ext2fs_swab32(f->i_dir_acl);
163	if (!islnk || has_data_blocks ) {
164		for (i = 0; i < EXT2_N_BLOCKS; i++)
165			t->i_block[i] = ext2fs_swab32(f->i_block[i]);
166	} else if (t != f) {
167		for (i = 0; i < EXT2_N_BLOCKS; i++)
168			t->i_block[i] = f->i_block[i];
169	}
170	t->i_generation = ext2fs_swab32(f->i_generation);
171	t->i_faddr = ext2fs_swab32(f->i_faddr);
172
173	switch (fs->super->s_creator_os) {
174	case EXT2_OS_LINUX:
175		t->osd1.linux1.l_i_version =
176			ext2fs_swab32(f->osd1.linux1.l_i_version);
177		t->osd2.linux2.l_i_blocks_hi =
178			ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi);
179		t->osd2.linux2.i_pad1 = ext2fs_swab16(f->osd2.linux2.i_pad1);
180		t->osd2.linux2.l_i_uid_high =
181		  ext2fs_swab16 (f->osd2.linux2.l_i_uid_high);
182		t->osd2.linux2.l_i_gid_high =
183		  ext2fs_swab16 (f->osd2.linux2.l_i_gid_high);
184		t->osd2.linux2.l_i_reserved2 =
185			ext2fs_swab32(f->osd2.linux2.l_i_reserved2);
186		break;
187	case EXT2_OS_HURD:
188		t->osd1.hurd1.h_i_translator =
189		  ext2fs_swab32 (f->osd1.hurd1.h_i_translator);
190		t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag;
191		t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize;
192		t->osd2.hurd2.h_i_mode_high =
193		  ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high);
194		t->osd2.hurd2.h_i_uid_high =
195		  ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high);
196		t->osd2.hurd2.h_i_gid_high =
197		  ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high);
198		t->osd2.hurd2.h_i_author =
199		  ext2fs_swab32 (f->osd2.hurd2.h_i_author);
200		break;
201	case EXT2_OS_MASIX:
202		t->osd1.masix1.m_i_reserved1 =
203			ext2fs_swab32(f->osd1.masix1.m_i_reserved1);
204		t->osd2.masix2.m_i_frag = f->osd2.masix2.m_i_frag;
205		t->osd2.masix2.m_i_fsize = f->osd2.masix2.m_i_fsize;
206		t->osd2.masix2.m_pad1 = ext2fs_swab16(f->osd2.masix2.m_pad1);
207		t->osd2.masix2.m_i_reserved2[0] =
208			ext2fs_swab32(f->osd2.masix2.m_i_reserved2[0]);
209		t->osd2.masix2.m_i_reserved2[1] =
210			ext2fs_swab32(f->osd2.masix2.m_i_reserved2[1]);
211		break;
212	}
213
214	if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
215		return; /* no i_extra_isize field */
216
217	if (hostorder)
218		extra_isize = f->i_extra_isize;
219	t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
220	if (!hostorder)
221		extra_isize = t->i_extra_isize;
222	if (extra_isize > EXT2_INODE_SIZE(fs->super) -
223				sizeof(struct ext2_inode)) {
224		/* this is error case: i_extra_size is too large */
225		return;
226	}
227
228	i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32);
229	if (bufsize < (int) i)
230		return; /* no space for EA magic */
231
232	eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
233					extra_isize);
234
235	if (ext2fs_swab32(*eaf) != EXT2_EXT_ATTR_MAGIC)
236		return; /* it seems no magic here */
237
238	eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
239					extra_isize);
240	*eat = ext2fs_swab32(*eaf);
241
242	/* convert EA(s) */
243	ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
244			     bufsize - sizeof(struct ext2_inode) -
245			     extra_isize - sizeof(__u32), 0);
246
247}
248
249void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t,
250		       struct ext2_inode *f, int hostorder)
251{
252	ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t,
253				(struct ext2_inode_large *) f, hostorder,
254				sizeof(struct ext2_inode));
255}
256
257#endif
258