2008-03-11 09:27:15

by Aneesh Kumar K.V

[permalink] [raw]
Subject: [PATCH] ext4: Return EIO if new block allocation returns block from system zone.

If the block allocator gets blocks out of system zone ext4 calls
ext4_error. But if the file system is mounted with errors=continue
return with -EIO.

System zone is the block range mapping block bitmap, inode bitmap and inode
table.

Signed-off-by: Aneesh Kumar K.V <[email protected]>
---
fs/ext4/balloc.c | 2 +-
fs/ext4/mballoc.c | 17 +++++++++++++----
2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 1e6c5dc..4a8cb53 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -1779,7 +1779,7 @@ allocated:
"Allocating block in system zone - "
"blocks from %llu, length %lu",
ret_block, num);
- goto out;
+ goto io_error;
}

performed_allocation = 1;
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 340daae..2eb8bd2 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -3079,9 +3079,11 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
in_range(block, ext4_inode_table(sb, gdp),
EXT4_SB(sb)->s_itb_per_group)) {

+ err = -EIO;
ext4_error(sb, __func__,
"Allocating block in system zone - block = %llu",
block);
+ goto out_err;
}
#ifdef AGGRESSIVE_CHECK
{
@@ -4345,10 +4347,15 @@ repeat:
}

if (likely(ac->ac_status == AC_STATUS_FOUND)) {
- ext4_mb_mark_diskspace_used(ac, handle);
- *errp = 0;
- block = ext4_grp_offs_to_block(sb, &ac->ac_b_ex);
- ar->len = ac->ac_b_ex.fe_len;
+ *errp = ext4_mb_mark_diskspace_used(ac, handle);
+ if (*errp) {
+ ac->ac_b_ex.fe_len = 0;
+ ar->len = 0;
+ ext4_mb_show_ac(ac);
+ } else {
+ block = ext4_grp_offs_to_block(sb, &ac->ac_b_ex);
+ ar->len = ac->ac_b_ex.fe_len;
+ }
} else {
freed = ext4_mb_discard_preallocations(sb, ac->ac_o_ex.fe_len);
if (freed)
@@ -4535,6 +4542,8 @@ do_more:
ext4_error(sb, __func__,
"Freeing blocks in system zone - "
"Block = %lu, count = %lu", block, count);
+ /* err = 0. ext4_std_error should be a no op */
+ goto error_return;
}

BUFFER_TRACE(bitmap_bh, "getting write access");
--
1.5.4.4.481.g5075.dirty