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Date: Sun, 29 Nov 2009 15:31:30 -0500
From: Theodore Ts'o <tytso@....edu>
To: Ext4 Developers List <linux-ext4@...r.kernel.org>
Cc: Mikulas Patocka <mikulas@...ax.karlin.mff.cuni.cz>,
Theodore Ts'o <tytso@....edu>
Subject: [PATCH -v2] e2fsck: Fix directory with holes even when i_size is wrong
The old method for detecting directories with holes depended on i_size
being correct, even though the correct value of i_size hadn't been
calculated yet. Hence, a directory inode with holes and an i_size of
0 would require two e2fsck passes to fix completely.
The replacement method for determining whether or not
ext2fs_add_dir_block() should be called is more reliable, and reduces
the size of e2fsck and makes the code more readable as a bonus.
Thanks to Mikulas Patocka for providing a sample file system which
demonstrated this problem.
Signed-off-by: "Theodore Ts'o" <tytso@....edu>
---
e2fsck/pass1.c | 59 ++++++++++++++-----------------------------------------
1 files changed, 15 insertions(+), 44 deletions(-)
diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index 2531e57..b534841 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -83,6 +83,7 @@ struct process_block_struct {
blk_t num_blocks;
blk_t max_blocks;
e2_blkcnt_t last_block;
+ e2_blkcnt_t last_db_block;
int num_illegal_blocks;
blk_t previous_block;
struct ext2_inode *inode;
@@ -767,6 +768,7 @@ void e2fsck_pass1(e2fsck_t ctx)
}
pb.ino = EXT2_BAD_INO;
pb.num_blocks = pb.last_block = 0;
+ pb.last_db_block = -1;
pb.num_illegal_blocks = 0;
pb.suppress = 0; pb.clear = 0; pb.is_dir = 0;
pb.is_reg = 0; pb.fragmented = 0; pb.bbcheck = 0;
@@ -1820,6 +1822,7 @@ static void check_blocks(e2fsck_t ctx, struct problem_context *pctx,
pb.ino = ino;
pb.num_blocks = 0;
pb.last_block = -1;
+ pb.last_db_block = -1;
pb.num_illegal_blocks = 0;
pb.suppress = 0; pb.clear = 0;
pb.fragmented = 0;
@@ -1883,26 +1886,6 @@ static void check_blocks(e2fsck_t ctx, struct problem_context *pctx,
return;
}
- if (pb.is_dir) {
- while (1) {
- struct ext2_db_entry *entry;
-
- if (ext2fs_dblist_get_last(fs->dblist, &entry) ||
- (entry->ino != ino) ||
- (entry->blk != 0) ||
- (entry->blockcnt == 0))
- break;
- /* printf("Dropping ino %lu blk %lu blockcnt %d\n",
- entry->ino, entry->blk, entry->blockcnt); */
- ext2fs_dblist_drop_last(fs->dblist);
- if (ext2fs_dblist_get_last(fs->dblist, &entry) ||
- (entry->ino != ino))
- pb.last_block--;
- else
- pb.last_block = entry->blockcnt;
- }
- }
-
if (inode->i_flags & EXT2_INDEX_FL) {
if (handle_htree(ctx, pctx, ino, inode, block_buf)) {
inode->i_flags &= ~EXT2_INDEX_FL;
@@ -2094,31 +2077,8 @@ static int process_block(ext2_filsys fs,
return 0;
}
- if (blk == 0) {
- if (p->is_dir == 0) {
- /*
- * Should never happen, since only directories
- * get called with BLOCK_FLAG_HOLE
- */
-#if DEBUG_E2FSCK
- printf("process_block() called with blk == 0, "
- "blockcnt=%d, inode %lu???\n",
- blockcnt, p->ino);
-#endif
- return 0;
- }
- if (blockcnt < 0)
- return 0;
- if (blockcnt * fs->blocksize < p->inode->i_size) {
-#if 0
- printf("Missing block (#%d) in directory inode %lu!\n",
- blockcnt, p->ino);
-#endif
- p->last_block = blockcnt;
- goto mark_dir;
- }
+ if (blk == 0)
return 0;
- }
#if 0
printf("Process_block, inode %lu, block %u, #%d\n", p->ino, blk,
@@ -2203,11 +2163,22 @@ static int process_block(ext2_filsys fs,
p->last_block = blockcnt;
mark_dir:
if (p->is_dir && (blockcnt >= 0)) {
+ while (++p->last_db_block < blockcnt) {
+ pctx->errcode = ext2fs_add_dir_block(fs->dblist,
+ p->ino, 0,
+ p->last_db_block);
+ if (pctx->errcode) {
+ pctx->blk = 0;
+ pctx->num = p->last_db_block;
+ goto failed_add_dir_block;
+ }
+ }
pctx->errcode = ext2fs_add_dir_block(fs->dblist, p->ino,
blk, blockcnt);
if (pctx->errcode) {
pctx->blk = blk;
pctx->num = blockcnt;
+ failed_add_dir_block:
fix_problem(ctx, PR_1_ADD_DBLOCK, pctx);
/* Should never get here */
ctx->flags |= E2F_FLAG_ABORT;
--
1.6.5.216.g5288a.dirty
--
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