• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 "config.h"
17 #include "e2fsck.h"
18 #include "problem.h"
19 #include <ext2fs/ext2_ext_attr.h>
20 
21 /*
22  * This routine is called when an inode is not connected to the
23  * directory tree.
24  *
25  * This subroutine returns 1 then the caller shouldn't bother with the
26  * rest of the pass 4 tests.
27  */
disconnect_inode(e2fsck_t ctx,ext2_ino_t i,struct ext2_inode_large * inode)28 static int disconnect_inode(e2fsck_t ctx, ext2_ino_t i,
29 			    struct ext2_inode_large *inode)
30 {
31 	ext2_filsys fs = ctx->fs;
32 	struct problem_context	pctx;
33 	__u32 eamagic = 0;
34 	int extra_size = 0;
35 
36 	e2fsck_read_inode_full(ctx, i, EXT2_INODE(inode),
37 			       EXT2_INODE_SIZE(fs->super),
38 			       "pass4: disconnect_inode");
39 	if (EXT2_INODE_SIZE(fs->super) > EXT2_GOOD_OLD_INODE_SIZE)
40 		extra_size = inode->i_extra_isize;
41 	clear_problem_context(&pctx);
42 	pctx.ino = i;
43 	pctx.inode = EXT2_INODE(inode);
44 
45 	if (EXT2_INODE_SIZE(fs->super) -EXT2_GOOD_OLD_INODE_SIZE -extra_size >0)
46 		eamagic = *(__u32 *)(((char *)inode) +EXT2_GOOD_OLD_INODE_SIZE +
47 				     extra_size);
48 	/*
49 	 * Offer to delete any zero-length files that does not have
50 	 * blocks.  If there is an EA block, it might have useful
51 	 * information, so we won't prompt to delete it, but let it be
52 	 * reconnected to lost+found.
53 	 */
54 	if (!inode->i_blocks && eamagic != EXT2_EXT_ATTR_MAGIC &&
55 	    (LINUX_S_ISREG(inode->i_mode) || LINUX_S_ISDIR(inode->i_mode))) {
56 		if (fix_problem(ctx, PR_4_ZERO_LEN_INODE, &pctx)) {
57 			e2fsck_clear_inode(ctx, i, EXT2_INODE(inode), 0,
58 					   "disconnect_inode");
59 			/*
60 			 * Fix up the bitmaps...
61 			 */
62 			e2fsck_read_bitmaps(ctx);
63 			ext2fs_inode_alloc_stats2(fs, i, -1,
64 						  LINUX_S_ISDIR(inode->i_mode));
65 			quota_data_inodes(ctx->qctx, inode, i, -1);
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_large	*inode;
94 	int inode_size = EXT2_INODE_SIZE(fs->super);
95 #ifdef RESOURCE_TRACK
96 	struct resource_track	rtrack;
97 #endif
98 	struct problem_context	pctx;
99 	__u16	link_count, link_counted;
100 	char	*buf = 0;
101 	dgrp_t	group, maxgroup;
102 
103 	init_resource_track(&rtrack, ctx->fs->io);
104 
105 #ifdef MTRACE
106 	mtrace_print("Pass 4");
107 #endif
108 	/*
109 	 * Since pass4 is mostly CPU bound, start readahead of bitmaps
110 	 * ahead of pass 5 if we haven't already loaded them.
111 	 */
112 	if (ctx->readahead_kb &&
113 	    (fs->block_map == NULL || fs->inode_map == NULL))
114 		e2fsck_readahead(fs, E2FSCK_READA_BBITMAP |
115 				     E2FSCK_READA_IBITMAP,
116 				 0, fs->group_desc_count);
117 
118 	clear_problem_context(&pctx);
119 
120 	if (!(ctx->options & E2F_OPT_PREEN))
121 		fix_problem(ctx, PR_4_PASS_HEADER, &pctx);
122 
123 	group = 0;
124 	maxgroup = fs->group_desc_count;
125 	if (ctx->progress)
126 		if ((ctx->progress)(ctx, 4, 0, maxgroup))
127 			return;
128 
129 	inode = e2fsck_allocate_memory(ctx, inode_size, "scratch inode");
130 
131 	/* Protect loop from wrap-around if s_inodes_count maxed */
132 	for (i=1; i <= fs->super->s_inodes_count && i > 0; i++) {
133 		int isdir;
134 
135 		if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
136 			goto errout;
137 		if ((i % fs->super->s_inodes_per_group) == 0) {
138 			group++;
139 			if (ctx->progress)
140 				if ((ctx->progress)(ctx, 4, group, maxgroup))
141 					goto errout;
142 		}
143 		if (i == quota_type2inum(PRJQUOTA, ctx->fs->super) ||
144 		    i == EXT2_BAD_INO ||
145 		    (i > EXT2_ROOT_INO && i < EXT2_FIRST_INODE(fs->super)))
146 			continue;
147 		if (!(ext2fs_test_inode_bitmap2(ctx->inode_used_map, i)) ||
148 		    (ctx->inode_imagic_map &&
149 		     ext2fs_test_inode_bitmap2(ctx->inode_imagic_map, i)) ||
150 		    (ctx->inode_bb_map &&
151 		     ext2fs_test_inode_bitmap2(ctx->inode_bb_map, i)))
152 			continue;
153 		ext2fs_icount_fetch(ctx->inode_link_info, i, &link_count);
154 		ext2fs_icount_fetch(ctx->inode_count, i, &link_counted);
155 		if (link_counted == 0) {
156 			if (!buf)
157 				buf = e2fsck_allocate_memory(ctx,
158 				     fs->blocksize, "bad_inode buffer");
159 			if (e2fsck_process_bad_inode(ctx, 0, i, buf))
160 				continue;
161 			if (disconnect_inode(ctx, i, inode))
162 				continue;
163 			ext2fs_icount_fetch(ctx->inode_link_info, i,
164 					    &link_count);
165 			ext2fs_icount_fetch(ctx->inode_count, i,
166 					    &link_counted);
167 		}
168 		isdir = ext2fs_test_inode_bitmap2(ctx->inode_dir_map, i);
169 		if (isdir && (link_counted > EXT2_LINK_MAX))
170 			link_counted = 1;
171 		if (link_counted != link_count) {
172 			e2fsck_read_inode_full(ctx, i, EXT2_INODE(inode),
173 					       inode_size, "pass4");
174 			pctx.ino = i;
175 			pctx.inode = EXT2_INODE(inode);
176 			if ((link_count != inode->i_links_count) && !isdir &&
177 			    (inode->i_links_count <= EXT2_LINK_MAX)) {
178 				pctx.num = link_count;
179 				fix_problem(ctx,
180 					    PR_4_INCONSISTENT_COUNT, &pctx);
181 			}
182 			pctx.num = link_counted;
183 			/* i_link_count was previously exceeded, but no longer
184 			 * is, fix this but don't consider it an error */
185 			if ((isdir && link_counted > 1 &&
186 			     (inode->i_flags & EXT2_INDEX_FL) &&
187 			     link_count == 1 && !(ctx->options & E2F_OPT_NO)) ||
188 			    fix_problem(ctx, PR_4_BAD_REF_COUNT, &pctx)) {
189 				inode->i_links_count = link_counted;
190 				e2fsck_write_inode_full(ctx, i,
191 							EXT2_INODE(inode),
192 							inode_size, "pass4");
193 			}
194 		}
195 	}
196 	ext2fs_free_icount(ctx->inode_link_info); ctx->inode_link_info = 0;
197 	ext2fs_free_icount(ctx->inode_count); ctx->inode_count = 0;
198 	ext2fs_free_inode_bitmap(ctx->inode_bb_map);
199 	ctx->inode_bb_map = 0;
200 	ext2fs_free_inode_bitmap(ctx->inode_imagic_map);
201 	ctx->inode_imagic_map = 0;
202 errout:
203 	if (buf)
204 		ext2fs_free_mem(&buf);
205 
206 	ext2fs_free_mem(&inode);
207 	print_resource_track(ctx, _("Pass 4"), &rtrack, ctx->fs->io);
208 }
209 
210