1 /*
2 * pass4.c -- pass #4 of e2fsck: Check reference counts
3 *
4 * Copyright (C) 1993, 1994, 1995, 1996, 1997 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 * Pass 4 frees the following data structures:
12 * - A bitmap of which inodes are in bad blocks. (inode_bb_map)
13 * - A bitmap of which inodes are imagic inodes. (inode_imagic_map)
14 */
15
16 #include "e2fsck.h"
17 #include "problem.h"
18 #include <ext2fs/ext2_ext_attr.h>
19
20 /*
21 * This routine is called when an inode is not connected to the
22 * directory tree.
23 *
24 * This subroutine returns 1 then the caller shouldn't bother with the
25 * rest of the pass 4 tests.
26 */
disconnect_inode(e2fsck_t ctx,ext2_ino_t i,struct ext2_inode * inode)27 static int disconnect_inode(e2fsck_t ctx, ext2_ino_t i,
28 struct ext2_inode *inode)
29 {
30 ext2_filsys fs = ctx->fs;
31 struct problem_context pctx;
32 __u32 eamagic = 0;
33 int extra_size = 0;
34
35 if (EXT2_INODE_SIZE(fs->super) > EXT2_GOOD_OLD_INODE_SIZE) {
36 e2fsck_read_inode_full(ctx, i, inode,EXT2_INODE_SIZE(fs->super),
37 "pass4: disconnect_inode");
38 extra_size = ((struct ext2_inode_large *)inode)->i_extra_isize;
39 } else {
40 e2fsck_read_inode(ctx, i, inode, "pass4: disconnect_inode");
41 }
42 clear_problem_context(&pctx);
43 pctx.ino = i;
44 pctx.inode = inode;
45
46 if (EXT2_INODE_SIZE(fs->super) -EXT2_GOOD_OLD_INODE_SIZE -extra_size >0)
47 eamagic = *(__u32 *)(((char *)inode) +EXT2_GOOD_OLD_INODE_SIZE +
48 extra_size);
49 /*
50 * Offer to delete any zero-length files that does not have
51 * blocks. If there is an EA block, it might have useful
52 * information, so we won't prompt to delete it, but let it be
53 * reconnected to lost+found.
54 */
55 if (!inode->i_blocks && eamagic != EXT2_EXT_ATTR_MAGIC &&
56 (LINUX_S_ISREG(inode->i_mode) || LINUX_S_ISDIR(inode->i_mode))) {
57 if (fix_problem(ctx, PR_4_ZERO_LEN_INODE, &pctx)) {
58 e2fsck_clear_inode(ctx, i, inode, 0,
59 "disconnect_inode");
60 /*
61 * Fix up the bitmaps...
62 */
63 e2fsck_read_bitmaps(ctx);
64 ext2fs_inode_alloc_stats2(fs, i, -1,
65 LINUX_S_ISDIR(inode->i_mode));
66 return 0;
67 }
68 }
69
70 /*
71 * Prompt to reconnect.
72 */
73 if (fix_problem(ctx, PR_4_UNATTACHED_INODE, &pctx)) {
74 if (e2fsck_reconnect_file(ctx, i))
75 ext2fs_unmark_valid(fs);
76 } else {
77 /*
78 * If we don't attach the inode, then skip the
79 * i_links_test since there's no point in trying to
80 * force i_links_count to zero.
81 */
82 ext2fs_unmark_valid(fs);
83 return 1;
84 }
85 return 0;
86 }
87
88
e2fsck_pass4(e2fsck_t ctx)89 void e2fsck_pass4(e2fsck_t ctx)
90 {
91 ext2_filsys fs = ctx->fs;
92 ext2_ino_t i;
93 struct ext2_inode *inode;
94 #ifdef RESOURCE_TRACK
95 struct resource_track rtrack;
96 #endif
97 struct problem_context pctx;
98 __u16 link_count, link_counted;
99 char *buf = 0;
100 int group, maxgroup;
101
102 init_resource_track(&rtrack, ctx->fs->io);
103
104 #ifdef MTRACE
105 mtrace_print("Pass 4");
106 #endif
107
108 clear_problem_context(&pctx);
109
110 if (!(ctx->options & E2F_OPT_PREEN))
111 fix_problem(ctx, PR_4_PASS_HEADER, &pctx);
112
113 group = 0;
114 maxgroup = fs->group_desc_count;
115 if (ctx->progress)
116 if ((ctx->progress)(ctx, 4, 0, maxgroup))
117 return;
118
119 inode = e2fsck_allocate_memory(ctx, EXT2_INODE_SIZE(fs->super),
120 "scratch inode");
121
122 /* Protect loop from wrap-around if s_inodes_count maxed */
123 for (i=1; i <= fs->super->s_inodes_count && i > 0; i++) {
124 if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
125 goto errout;
126 if ((i % fs->super->s_inodes_per_group) == 0) {
127 group++;
128 if (ctx->progress)
129 if ((ctx->progress)(ctx, 4, group, maxgroup))
130 goto errout;
131 }
132 if (i == EXT2_BAD_INO ||
133 (i > EXT2_ROOT_INO && i < EXT2_FIRST_INODE(fs->super)))
134 continue;
135 if (!(ext2fs_test_inode_bitmap(ctx->inode_used_map, i)) ||
136 (ctx->inode_imagic_map &&
137 ext2fs_test_inode_bitmap(ctx->inode_imagic_map, i)) ||
138 (ctx->inode_bb_map &&
139 ext2fs_test_inode_bitmap(ctx->inode_bb_map, i)))
140 continue;
141 ext2fs_icount_fetch(ctx->inode_link_info, i, &link_count);
142 ext2fs_icount_fetch(ctx->inode_count, i, &link_counted);
143 if (link_counted == 0) {
144 if (!buf)
145 buf = e2fsck_allocate_memory(ctx,
146 fs->blocksize, "bad_inode buffer");
147 if (e2fsck_process_bad_inode(ctx, 0, i, buf))
148 continue;
149 if (disconnect_inode(ctx, i, inode))
150 continue;
151 ext2fs_icount_fetch(ctx->inode_link_info, i,
152 &link_count);
153 ext2fs_icount_fetch(ctx->inode_count, i,
154 &link_counted);
155 }
156 if (ext2fs_test_inode_bitmap(ctx->inode_dir_map, i) &&
157 (link_counted > EXT2_LINK_MAX))
158 link_counted = 1;
159 if (link_counted != link_count) {
160 e2fsck_read_inode(ctx, i, inode, "pass4");
161 pctx.ino = i;
162 pctx.inode = inode;
163 if (link_count != inode->i_links_count) {
164 pctx.num = link_count;
165 fix_problem(ctx,
166 PR_4_INCONSISTENT_COUNT, &pctx);
167 }
168 pctx.num = link_counted;
169 /* i_link_count was previously exceeded, but no longer
170 * is, fix this but don't consider it an error */
171 if ((LINUX_S_ISDIR(inode->i_mode) && link_counted > 1 &&
172 (inode->i_flags & EXT2_INDEX_FL) &&
173 link_count == 1 && !(ctx->options & E2F_OPT_NO)) ||
174 (fix_problem(ctx, PR_4_BAD_REF_COUNT, &pctx))) {
175 inode->i_links_count = link_counted;
176 e2fsck_write_inode(ctx, i, inode, "pass4");
177 }
178 }
179 }
180 ext2fs_free_icount(ctx->inode_link_info); ctx->inode_link_info = 0;
181 ext2fs_free_icount(ctx->inode_count); ctx->inode_count = 0;
182 ext2fs_free_inode_bitmap(ctx->inode_bb_map);
183 ctx->inode_bb_map = 0;
184 ext2fs_free_inode_bitmap(ctx->inode_imagic_map);
185 ctx->inode_imagic_map = 0;
186 errout:
187 if (buf)
188 ext2fs_free_mem(&buf);
189
190 ext2fs_free_mem(&inode);
191 print_resource_track(ctx, _("Pass 4"), &rtrack, ctx->fs->io);
192 }
193
194