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Message-ID: <20110901003804.1176.90447.stgit@elm3c44.beaverton.ibm.com>
Date: Wed, 31 Aug 2011 17:38:04 -0700
From: "Darrick J. Wong" <djwong@...ibm.com>
To: Andreas Dilger <adilger.kernel@...ger.ca>,
Theodore Tso <tytso@....edu>,
"Darrick J. Wong" <djwong@...ibm.com>
Cc: Sunil Mushran <sunil.mushran@...cle.com>,
Amir Goldstein <amir73il@...il.com>,
Andi Kleen <andi@...stfloor.org>,
Mingming Cao <cmm@...ibm.com>,
Joel Becker <jlbec@...lplan.org>, linux-ext4@...r.kernel.org,
Coly Li <colyli@...il.com>
Subject: [PATCH 27/37] e2fsck: Check directory leaf block checksums
Checks that directory leaf blocks have the necessary fake dir_entry at the end
of the block to hold a checksum and that the checksum is valid. It will resize
the block and/or rebuild the directory if necessary.
Signed-off-by: Darrick J. Wong <djwong@...ibm.com>
---
e2fsck/e2fsck.h | 1 +
e2fsck/pass2.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++------
e2fsck/pass3.c | 4 +++
e2fsck/problem.c | 10 +++++++
e2fsck/problem.h | 6 ++++
e2fsck/rehash.c | 12 +++++++++
6 files changed, 101 insertions(+), 8 deletions(-)
diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h
index d515a9d..2a7a80e 100644
--- a/e2fsck/e2fsck.h
+++ b/e2fsck/e2fsck.h
@@ -473,6 +473,7 @@ extern void region_free(region_t region);
extern int region_allocate(region_t region, region_addr_t start, int n);
/* rehash.c */
+int e2fsck_dir_will_be_rehashed(e2fsck_t ctx, ext2_ino_t ino);
errcode_t e2fsck_rehash_dir(e2fsck_t ctx, ext2_ino_t ino);
void e2fsck_rehash_directories(e2fsck_t ctx);
diff --git a/e2fsck/pass2.c b/e2fsck/pass2.c
index 93a09d1..4563c9c 100644
--- a/e2fsck/pass2.c
+++ b/e2fsck/pass2.c
@@ -748,7 +748,8 @@ static int check_dir_block(ext2_filsys fs,
struct problem_context pctx;
int dups_found = 0;
int ret;
- int csum_size = 0;
+ int dx_csum_size = 0, de_csum_size = 0;
+ int is_leaf = 1;
cd = (struct check_dir_struct *) priv_data;
buf = cd->buf;
@@ -761,8 +762,10 @@ static int check_dir_block(ext2_filsys fs,
return DIRENT_ABORT;
if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
- EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
- csum_size = sizeof(struct ext2_dx_tail);
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
+ dx_csum_size = sizeof(struct ext2_dx_tail);
+ de_csum_size = sizeof(struct ext2_dir_entry_tail);
+ }
/*
* Make sure the inode is still in use (could have been
@@ -806,11 +809,15 @@ static int check_dir_block(ext2_filsys fs,
if (cd->pctx.errcode == EXT2_ET_DIR_CORRUPTED)
cd->pctx.errcode = 0; /* We'll handle this ourselves */
if (cd->pctx.errcode) {
+ char *buf2;
if (!fix_problem(ctx, PR_2_READ_DIRBLOCK, &cd->pctx)) {
ctx->flags |= E2F_FLAG_ABORT;
return DIRENT_ABORT;
}
- memset(buf, 0, fs->blocksize);
+ ext2fs_new_dir_block(fs, db->blockcnt == 0 ? ino : 0,
+ EXT2_ROOT_INO, &buf2);
+ memcpy(buf, buf2, fs->blocksize);
+ ext2fs_free_mem(&buf2);
}
#ifdef ENABLE_HTREE
dx_dir = e2fsck_get_dx_dir_info(ctx, ino);
@@ -855,13 +862,49 @@ static int check_dir_block(ext2_filsys fs,
(rec_len == fs->blocksize) &&
(dirent->name_len == 0) &&
(ext2fs_le16_to_cpu(limit->limit) ==
- ((fs->blocksize - (8 + csum_size)) /
+ ((fs->blocksize - (8 + dx_csum_size)) /
sizeof(struct ext2_dx_entry))))
dx_db->type = DX_DIRBLOCK_NODE;
+ is_leaf = 0;
}
out_htree:
#endif /* ENABLE_HTREE */
+ /* Verify checksum. */
+ if (is_leaf && de_csum_size) {
+ /* No space for csum? Rebuild dirs in pass 3A. */
+ if (!ext2fs_dirent_has_tail(fs, (struct ext2_dir_entry *)buf)) {
+ de_csum_size = 0;
+ if (e2fsck_dir_will_be_rehashed(ctx, ino))
+ goto skip_checksum;
+ if (!fix_problem(cd->ctx, PR_2_LEAF_NODE_MISSING_CSUM,
+ &cd->pctx))
+ goto skip_checksum;
+ if (!ctx->dirs_to_hash)
+ ext2fs_u32_list_create(&ctx->dirs_to_hash, 50);
+ if (ctx->dirs_to_hash)
+ ext2fs_u32_list_add(ctx->dirs_to_hash, ino);
+ goto skip_checksum;
+ }
+ if (!ext2fs_dirent_csum_verify(fs, ino,
+ (struct ext2_dir_entry *)buf)) {
+ char *buf2;
+ if (!fix_problem(cd->ctx, PR_2_LEAF_NODE_CSUM_INVALID,
+ &cd->pctx))
+ goto skip_checksum;
+ ext2fs_new_dir_block(fs,
+ db->blockcnt == 0 ? ino : 0,
+ EXT2_ROOT_INO, &buf2);
+ memcpy(buf, buf2, fs->blocksize);
+ ext2fs_free_mem(&buf2);
+ dir_modified++;
+ }
+ }
+ /* htree nodes don't use fake dirents to store checksums */
+ if (!is_leaf)
+ de_csum_size = 0;
+
+skip_checksum:
dict_init(&de_dict, DICTCOUNT_T_MAX, dict_de_cmp);
prev = 0;
do {
@@ -1134,7 +1177,7 @@ out_htree:
(void) ext2fs_get_rec_len(fs, dirent, &rec_len);
offset += rec_len;
dot_state++;
- } while (offset < fs->blocksize);
+ } while (offset < fs->blocksize - de_csum_size);
#if 0
printf("\n");
#endif
@@ -1151,16 +1194,33 @@ out_htree:
parse_int_node(fs, db, cd, dx_dir, buf);
}
#endif /* ENABLE_HTREE */
- if (offset != fs->blocksize) {
- cd->pctx.num = rec_len - fs->blocksize + offset;
+
+ if (offset != fs->blocksize - de_csum_size) {
+ cd->pctx.num = rec_len - (fs->blocksize - de_csum_size) +
+ offset;
if (fix_problem(ctx, PR_2_FINAL_RECLEN, &cd->pctx)) {
dirent->rec_len = cd->pctx.num;
dir_modified++;
}
}
if (dir_modified) {
+ /* leaf block with no tail? Rehash dirs later. */
+ if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
+ is_leaf &&
+ !ext2fs_dirent_has_tail(fs, (struct ext2_dir_entry *)buf)) {
+ if (!ctx->dirs_to_hash)
+ ext2fs_u32_list_create(&ctx->dirs_to_hash, 50);
+ if (ctx->dirs_to_hash)
+ ext2fs_u32_list_add(ctx->dirs_to_hash, ino);
+ }
+
+ if (e2fsck_dir_will_be_rehashed(ctx, ino))
+ ctx->fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
cd->pctx.errcode = ext2fs_write_dir_block(fs, block_nr, buf,
ino);
+ if (e2fsck_dir_will_be_rehashed(ctx, ino))
+ ctx->fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
if (cd->pctx.errcode) {
if (!fix_problem(ctx, PR_2_WRITE_DIRBLOCK,
&cd->pctx))
diff --git a/e2fsck/pass3.c b/e2fsck/pass3.c
index 2360aff..ada6646 100644
--- a/e2fsck/pass3.c
+++ b/e2fsck/pass3.c
@@ -654,8 +654,12 @@ static void fix_dotdot(e2fsck_t ctx, ext2_ino_t ino, ext2_ino_t parent)
clear_problem_context(&pctx);
pctx.ino = ino;
+ if (e2fsck_dir_will_be_rehashed(ctx, ino))
+ ctx->fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
retval = ext2fs_dir_iterate(fs, ino, DIRENT_FLAG_INCLUDE_EMPTY,
0, fix_dotdot_proc, &fp);
+ if (e2fsck_dir_will_be_rehashed(ctx, ino))
+ ctx->fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
if (retval || !fp.done) {
pctx.errcode = retval;
fix_problem(ctx, retval ? PR_3_FIX_PARENT_ERR :
diff --git a/e2fsck/problem.c b/e2fsck/problem.c
index 637b254..835f0ff 100644
--- a/e2fsck/problem.c
+++ b/e2fsck/problem.c
@@ -1353,6 +1353,16 @@ static struct e2fsck_problem problem_table[] = {
N_("@p @h %d: node fails checksum\n"),
PROMPT_CLEAR_HTREE, PR_PREEN_OK },
+ /* leaf node fails checksum */
+ { PR_2_LEAF_NODE_CSUM_INVALID,
+ N_("@d @i %i, %B, offset %N: @d fails checksum\n"),
+ PROMPT_SALVAGE, 0 },
+
+ /* leaf node fails checksum */
+ { PR_2_LEAF_NODE_MISSING_CSUM,
+ N_("@d @i %i, %B, offset %N: @d has no checksum\n"),
+ PROMPT_FIX, PR_PREEN_OK },
+
/* Pass 3 errors */
/* Pass 3: Checking directory connectivity */
diff --git a/e2fsck/problem.h b/e2fsck/problem.h
index d4e596f..df29057 100644
--- a/e2fsck/problem.h
+++ b/e2fsck/problem.h
@@ -809,6 +809,12 @@ struct problem_context {
/* htree node fails checksum */
#define PR_2_HTREE_NODE_CSUM_INVALID 0x02004A
+/* dir leaf node fails checksum */
+#define PR_2_LEAF_NODE_CSUM_INVALID 0x02004B
+
+/* no space in leaf for checksum */
+#define PR_2_LEAF_NODE_MISSING_CSUM 0x02004C
+
/*
* Pass 3 errors
*/
diff --git a/e2fsck/rehash.c b/e2fsck/rehash.c
index 25cc8b8..ae6d406 100644
--- a/e2fsck/rehash.c
+++ b/e2fsck/rehash.c
@@ -51,6 +51,15 @@
#include "e2fsck.h"
#include "problem.h"
+int e2fsck_dir_will_be_rehashed(e2fsck_t ctx, ext2_ino_t ino)
+{
+ if (ctx->options & E2F_OPT_COMPRESS_DIRS)
+ return 1;
+ if (!ctx->dirs_to_hash)
+ return 0;
+ return ext2fs_u32_list_test(ctx->dirs_to_hash, ino);
+}
+
struct fill_dir_struct {
char *buf;
struct ext2_inode_large *inode;
@@ -905,8 +914,11 @@ void e2fsck_rehash_directories(e2fsck_t ctx)
if (!ext2fs_u32_list_iterate(iter, &ino))
break;
}
+#if 0
+ /* Why is lost_and_found never cleaned up or hashed? */
if (ino == ctx->lost_and_found)
continue;
+#endif
pctx.dir = ino;
if (first) {
fix_problem(ctx, PR_3A_PASS_HEADER, &pctx);
--
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