swapfs.c revision 8815fb8a00f5a441eb62f035353db9e0cca90b38
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_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
73void 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	gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused);
83	gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum);
84}
85
86void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header)
87{
88	struct ext2_ext_attr_header *from_header =
89		(struct ext2_ext_attr_header *)from;
90	struct ext2_ext_attr_header *to_header =
91		(struct ext2_ext_attr_header *)to;
92	struct ext2_ext_attr_entry *from_entry, *to_entry;
93	char *from_end = (char *)from_header + bufsize;
94	int n;
95
96	if (to_header != from_header)
97		memcpy(to_header, from_header, bufsize);
98
99	from_entry = (struct ext2_ext_attr_entry *)from_header;
100	to_entry   = (struct ext2_ext_attr_entry *)to_header;
101
102	if (has_header) {
103		to_header->h_magic    = ext2fs_swab32(from_header->h_magic);
104		to_header->h_blocks   = ext2fs_swab32(from_header->h_blocks);
105		to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
106		for (n=0; n<4; n++)
107			to_header->h_reserved[n] =
108				ext2fs_swab32(from_header->h_reserved[n]);
109		from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
110		to_entry   = (struct ext2_ext_attr_entry *)(to_header+1);
111	}
112
113	while ((char *)from_entry < from_end && *(__u32 *)from_entry) {
114		to_entry->e_value_offs  =
115			ext2fs_swab16(from_entry->e_value_offs);
116		to_entry->e_value_block =
117			ext2fs_swab32(from_entry->e_value_block);
118		to_entry->e_value_size  =
119			ext2fs_swab32(from_entry->e_value_size);
120		from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
121		to_entry   = EXT2_EXT_ATTR_NEXT(to_entry);
122	}
123}
124
125void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
126			    struct ext2_inode_large *f, int hostorder,
127			    int bufsize)
128{
129	unsigned i;
130	int islnk = 0;
131	__u32 *eaf, *eat;
132
133	if (hostorder && LINUX_S_ISLNK(f->i_mode))
134		islnk = 1;
135	t->i_mode = ext2fs_swab16(f->i_mode);
136	if (!hostorder && LINUX_S_ISLNK(t->i_mode))
137		islnk = 1;
138	t->i_uid = ext2fs_swab16(f->i_uid);
139	t->i_size = ext2fs_swab32(f->i_size);
140	t->i_atime = ext2fs_swab32(f->i_atime);
141	t->i_ctime = ext2fs_swab32(f->i_ctime);
142	t->i_mtime = ext2fs_swab32(f->i_mtime);
143	t->i_dtime = ext2fs_swab32(f->i_dtime);
144	t->i_gid = ext2fs_swab16(f->i_gid);
145	t->i_links_count = ext2fs_swab16(f->i_links_count);
146	t->i_blocks = ext2fs_swab32(f->i_blocks);
147	t->i_flags = ext2fs_swab32(f->i_flags);
148	t->i_file_acl = ext2fs_swab32(f->i_file_acl);
149	t->i_dir_acl = ext2fs_swab32(f->i_dir_acl);
150	if (!islnk || ext2fs_inode_data_blocks(fs, (struct ext2_inode *)t)) {
151		for (i = 0; i < EXT2_N_BLOCKS; i++)
152			t->i_block[i] = ext2fs_swab32(f->i_block[i]);
153	} else if (t != f) {
154		for (i = 0; i < EXT2_N_BLOCKS; i++)
155			t->i_block[i] = f->i_block[i];
156	}
157	t->i_generation = ext2fs_swab32(f->i_generation);
158	t->i_faddr = ext2fs_swab32(f->i_faddr);
159
160	switch (fs->super->s_creator_os) {
161	case EXT2_OS_LINUX:
162		t->osd1.linux1.l_i_reserved1 =
163			ext2fs_swab32(f->osd1.linux1.l_i_reserved1);
164		t->osd2.linux2.l_i_blocks_hi =
165			ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi);
166		t->osd2.linux2.i_pad1 = ext2fs_swab16(f->osd2.linux2.i_pad1);
167		t->osd2.linux2.l_i_uid_high =
168		  ext2fs_swab16 (f->osd2.linux2.l_i_uid_high);
169		t->osd2.linux2.l_i_gid_high =
170		  ext2fs_swab16 (f->osd2.linux2.l_i_gid_high);
171		t->osd2.linux2.l_i_reserved2 =
172			ext2fs_swab32(f->osd2.linux2.l_i_reserved2);
173		break;
174	case EXT2_OS_HURD:
175		t->osd1.hurd1.h_i_translator =
176		  ext2fs_swab32 (f->osd1.hurd1.h_i_translator);
177		t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag;
178		t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize;
179		t->osd2.hurd2.h_i_mode_high =
180		  ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high);
181		t->osd2.hurd2.h_i_uid_high =
182		  ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high);
183		t->osd2.hurd2.h_i_gid_high =
184		  ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high);
185		t->osd2.hurd2.h_i_author =
186		  ext2fs_swab32 (f->osd2.hurd2.h_i_author);
187		break;
188	case EXT2_OS_MASIX:
189		t->osd1.masix1.m_i_reserved1 =
190			ext2fs_swab32(f->osd1.masix1.m_i_reserved1);
191		t->osd2.masix2.m_i_frag = f->osd2.masix2.m_i_frag;
192		t->osd2.masix2.m_i_fsize = f->osd2.masix2.m_i_fsize;
193		t->osd2.masix2.m_pad1 = ext2fs_swab16(f->osd2.masix2.m_pad1);
194		t->osd2.masix2.m_i_reserved2[0] =
195			ext2fs_swab32(f->osd2.masix2.m_i_reserved2[0]);
196		t->osd2.masix2.m_i_reserved2[1] =
197			ext2fs_swab32(f->osd2.masix2.m_i_reserved2[1]);
198		break;
199	}
200
201	if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
202		return; /* no i_extra_isize field */
203
204	t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
205	if (t->i_extra_isize > EXT2_INODE_SIZE(fs->super) -
206				sizeof(struct ext2_inode)) {
207		/* this is error case: i_extra_size is too large */
208		return;
209	}
210
211	i = sizeof(struct ext2_inode) + t->i_extra_isize + sizeof(__u32);
212	if (bufsize < (int) i)
213		return; /* no space for EA magic */
214
215	eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
216					f->i_extra_isize);
217
218	if (ext2fs_swab32(*eaf) != EXT2_EXT_ATTR_MAGIC)
219		return; /* it seems no magic here */
220
221	eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
222					f->i_extra_isize);
223	*eat = ext2fs_swab32(*eaf);
224
225	/* convert EA(s) */
226	ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
227			     bufsize - sizeof(struct ext2_inode) -
228			     t->i_extra_isize - sizeof(__u32), 0);
229
230}
231
232void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t,
233		       struct ext2_inode *f, int hostorder)
234{
235	ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t,
236				(struct ext2_inode_large *) f, hostorder,
237				sizeof(struct ext2_inode));
238}
239
240#endif
241