• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * bmove.c --- Move blocks around to make way for a particular
3  * 	filesystem structure.
4  *
5  * Copyright (C) 1997 Theodore Ts'o.
6  *
7  * %Begin-Header%
8  * This file may be redistributed under the terms of the GNU Library
9  * General Public License, version 2.
10  * %End-Header%
11  */
12 
13 #include <stdio.h>
14 #include <string.h>
15 #if HAVE_UNISTD_H
16 #include <unistd.h>
17 #endif
18 #if HAVE_SYS_TYPES_H
19 #include <sys/types.h>
20 #endif
21 #if HAVE_SYS_TIME_H
22 #include <sys/time.h>
23 #endif
24 
25 #include "ext2_fs.h"
26 #include "ext2fsP.h"
27 
28 struct process_block_struct {
29 	ext2_ino_t		ino;
30 	struct ext2_inode *	inode;
31 	ext2fs_block_bitmap	reserve;
32 	ext2fs_block_bitmap	alloc_map;
33 	errcode_t		error;
34 	char			*buf;
35 	int			add_dir;
36 	int			flags;
37 };
38 
process_block(ext2_filsys fs,blk64_t * block_nr,e2_blkcnt_t blockcnt,blk64_t ref_block,int ref_offset,void * priv_data)39 static int process_block(ext2_filsys fs, blk64_t *block_nr,
40 			 e2_blkcnt_t blockcnt, blk64_t ref_block,
41 			 int ref_offset, void *priv_data)
42 {
43 	struct process_block_struct *pb;
44 	errcode_t	retval;
45 	int		ret;
46 	blk64_t		block, orig;
47 
48 	pb = (struct process_block_struct *) priv_data;
49 	block = orig = *block_nr;
50 	ret = 0;
51 
52 	/*
53 	 * Let's see if this is one which we need to relocate
54 	 */
55 	if (ext2fs_test_block_bitmap2(pb->reserve, block)) {
56 		do {
57 			if (++block >= ext2fs_blocks_count(fs->super))
58 				block = fs->super->s_first_data_block;
59 			if (block == orig) {
60 				pb->error = EXT2_ET_BLOCK_ALLOC_FAIL;
61 				return BLOCK_ABORT;
62 			}
63 		} while (ext2fs_test_block_bitmap2(pb->reserve, block) ||
64 			 ext2fs_test_block_bitmap2(pb->alloc_map, block));
65 
66 		retval = io_channel_read_blk64(fs->io, orig, 1, pb->buf);
67 		if (retval) {
68 			pb->error = retval;
69 			return BLOCK_ABORT;
70 		}
71 		retval = io_channel_write_blk64(fs->io, block, 1, pb->buf);
72 		if (retval) {
73 			pb->error = retval;
74 			return BLOCK_ABORT;
75 		}
76 		*block_nr = block;
77 		ext2fs_mark_block_bitmap2(pb->alloc_map, block);
78 		ret = BLOCK_CHANGED;
79 		if (pb->flags & EXT2_BMOVE_DEBUG)
80 			printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
81 			       (unsigned) pb->ino, blockcnt,
82 			       (unsigned long long) orig,
83 			       (unsigned long long) block);
84 	}
85 	if (pb->add_dir) {
86 		retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
87 					       block, blockcnt);
88 		if (retval) {
89 			pb->error = retval;
90 			ret |= BLOCK_ABORT;
91 		}
92 	}
93 	return ret;
94 }
95 
ext2fs_move_blocks(ext2_filsys fs,ext2fs_block_bitmap reserve,ext2fs_block_bitmap alloc_map,int flags)96 errcode_t ext2fs_move_blocks(ext2_filsys fs,
97 			     ext2fs_block_bitmap reserve,
98 			     ext2fs_block_bitmap alloc_map,
99 			     int flags)
100 {
101 	ext2_ino_t	ino;
102 	struct ext2_inode inode;
103 	errcode_t	retval;
104 	struct process_block_struct pb;
105 	ext2_inode_scan	scan;
106 	char		*block_buf;
107 
108 	retval = ext2fs_open_inode_scan(fs, 0, &scan);
109 	if (retval)
110 		return retval;
111 
112 	pb.reserve = reserve;
113 	pb.error = 0;
114 	pb.alloc_map = alloc_map ? alloc_map : fs->block_map;
115 	pb.flags = flags;
116 
117 	retval = ext2fs_get_array(4, fs->blocksize, &block_buf);
118 	if (retval)
119 		return retval;
120 	pb.buf = block_buf + fs->blocksize * 3;
121 
122 	/*
123 	 * If GET_DBLIST is set in the flags field, then we should
124 	 * gather directory block information while we're doing the
125 	 * block move.
126 	 */
127 	if (flags & EXT2_BMOVE_GET_DBLIST) {
128 		if (fs->dblist) {
129 			ext2fs_free_dblist(fs->dblist);
130 			fs->dblist = NULL;
131 		}
132 		retval = ext2fs_init_dblist(fs, 0);
133 		if (retval)
134 			return retval;
135 	}
136 
137 	retval = ext2fs_get_next_inode(scan, &ino, &inode);
138 	if (retval)
139 		return retval;
140 
141 	while (ino) {
142 		if ((inode.i_links_count == 0) ||
143 		    !ext2fs_inode_has_valid_blocks2(fs, &inode))
144 			goto next;
145 
146 		pb.ino = ino;
147 		pb.inode = &inode;
148 
149 		pb.add_dir = (LINUX_S_ISDIR(inode.i_mode) &&
150 			      flags & EXT2_BMOVE_GET_DBLIST);
151 
152 		retval = ext2fs_block_iterate3(fs, ino, 0, block_buf,
153 					       process_block, &pb);
154 		if (retval)
155 			return retval;
156 		if (pb.error)
157 			return pb.error;
158 
159 	next:
160 		retval = ext2fs_get_next_inode(scan, &ino, &inode);
161 		if (retval == EXT2_ET_BAD_BLOCK_IN_INODE_TABLE)
162 			goto next;
163 	}
164 	return 0;
165 }
166 
167