If we have failed some where inside ext4_get_blocks() internals we may
have allocated some new blocks, which was not yet claimed to quota.
We have to free such blocks, but without touching quota. Quota will
be updated later on exit from ext4_get_blocks().
There are two possible ways to understand what we have to skip quota update:
1) Caller pass corresponding flag to ext4_free_blocks()
2) check that free_blocks() was indirectly called by get_blocks()
(i.e EXT4_I(inode)->i_delalloc_reserved_flag is set)
Second is simpler, but may result in unpredictable consequences later.
So i've chosen the first one, because caller must know which blocks it
is freeing.
The bug happens on heavily loaded node, or with 227'th xfstestcase and
result in incorrect i_blocks (less than expected). So truncation for
that file result in i_blocks overflow.
Seems this was the last bug which was easily triggered by 227'th testcase.
Test hosts survived for 24hrs without complain. Tested configuration:
* ext3 over ext4driver with -odelalloc mount option
* ext4 with default mount opt
>From ff4594462fe9101042df9c47a7c35cddd809db4f Mon Sep 17 00:00:00 2001
From: Dmitry Monakhov <dmonakhov@xxxxxxxxxx>
Date: Tue, 27 Apr 2010 06:49:28 +0400
Subject: [PATCH] ext4: Do not drop quota for reserved blocks on error paths
If we have failed some where inside ext4_get_blocks() internals we may
have allocated some new blocks, which was not yet claimed to quota.
We have to free such blocks, but without touching quota. Quota will
be updated later on exit from ext4_get_blocks().
The bug happens on heavily loaded node.
Signed-off-by: Dmitry Monakhov <dmonakhov@xxxxxxxxxx>
---
fs/ext4/ext4.h | 1 +
fs/ext4/extents.c | 18 +++++++++++++-----
fs/ext4/inode.c | 26 +++++++++++++++++---------
fs/ext4/mballoc.c | 2 +-
4 files changed, 32 insertions(+), 15 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index c69efb2..c009805 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -401,6 +401,7 @@ struct ext4_new_group_data {
#define EXT4_FREE_BLOCKS_METADATA 0x0001
#define EXT4_FREE_BLOCKS_FORGET 0x0002
#define EXT4_FREE_BLOCKS_VALIDATED 0x0004
+#define EXT4_FREE_BLOCKS_NOQUOTA 0x0008
/*
* ioctl commands
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 6856272..815fd97 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -1057,11 +1057,15 @@ cleanup:
if (err) {
/* free all allocated blocks in error case */
+ int fb_flags = EXT4_FREE_BLOCKS_METADATA;
+ if (EXT4_I(inode)->i_delalloc_reserved_flag)
+ fb_flags |= EXT4_FREE_BLOCKS_NOQUOTA;
+
for (i = 0; i < depth; i++) {
if (!ablocks[i])
continue;
ext4_free_blocks(handle, inode, 0, ablocks[i], 1,
- EXT4_FREE_BLOCKS_METADATA);
+ fb_flags);
}
}
kfree(ablocks);
@@ -3553,12 +3557,16 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
}
err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
if (err) {
- /* free data blocks we just allocated */
- /* not a good idea to call discard here directly,
- * but otherwise we'd need to call it every free() */
+ int fb_flags = 0;
+ /* free data blocks we just allocated
+ * Not a good idea to call discard here directly,
+ * but otherwise we'd need to call it every free().
+ * On delalloc blocks are not yet accounted to quota */
+ if (EXT4_I(inode)->i_delalloc_reserved_flag)
+ fb_flags = EXT4_FREE_BLOCKS_NOQUOTA;
ext4_discard_preallocations(inode);
ext4_free_blocks(handle, inode, 0, ext_pblock(&newex),
- ext4_ext_get_actual_len(&newex), 0);
+ ext4_ext_get_actual_len(&newex), fb_flags);
goto out2;
}
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index e4e0a7d..58a3787 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -591,7 +591,9 @@ static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
int index = 0;
ext4_fsblk_t current_block = 0;
int ret = 0;
-
+ int fb_flags = 0;
+ if (EXT4_I(inode)->i_delalloc_reserved_flag)
+ fb_flags |= EXT4_FREE_BLOCKS_NOQUOTA;
/*
* Here we try to allocate the requested multiple blocks at once,
* on a best-effort basis.
@@ -686,7 +688,7 @@ allocated:
return ret;
failed_out:
for (i = 0; i < index; i++)
- ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, 0);
+ ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, fb_flags);
return ret;
}
@@ -727,6 +729,9 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
int num;
ext4_fsblk_t new_blocks[4];
ext4_fsblk_t current_block;
+ int fb_flags = 0;
+ if (EXT4_I(inode)->i_delalloc_reserved_flag)
+ fb_flags |= EXT4_FREE_BLOCKS_NOQUOTA;
num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks,
*blks, new_blocks, &err);
@@ -782,20 +787,20 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
return err;
failed:
/* Allocation failed, free what we already allocated */
- ext4_free_blocks(handle, inode, 0, new_blocks[0], 1, 0);
+ ext4_free_blocks(handle, inode, 0, new_blocks[0], 1, fb_flags);
for (i = 1; i <= n ; i++) {
- /*
+ /*
* branch[i].bh is newly allocated, so there is no
* need to revoke the block, which is why we don't
* need to set EXT4_FREE_BLOCKS_METADATA.
*/
ext4_free_blocks(handle, inode, 0, new_blocks[i], 1,
- EXT4_FREE_BLOCKS_FORGET);
+ fb_flags | EXT4_FREE_BLOCKS_FORGET);
}
for (i = n+1; i < indirect_blks; i++)
- ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, 0);
+ ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, fb_flags);
- ext4_free_blocks(handle, inode, 0, new_blocks[i], num, 0);
+ ext4_free_blocks(handle, inode, 0, new_blocks[i], num, fb_flags);
return err;
}
@@ -821,6 +826,9 @@ static int ext4_splice_branch(handle_t *handle, struct inode *inode,
int i;
int err = 0;
ext4_fsblk_t current_block;
+ int fb_flags = 0;
+ if (EXT4_I(inode)->i_delalloc_reserved_flag)
+ fb_flags |= EXT4_FREE_BLOCKS_NOQUOTA;
/*
* If we're splicing into a [td]indirect block (as opposed to the
@@ -880,10 +888,10 @@ err_out:
* need to set EXT4_FREE_BLOCKS_METADATA.
*/
ext4_free_blocks(handle, inode, where[i].bh, 0, 1,
- EXT4_FREE_BLOCKS_FORGET);
+ fb_flags | EXT4_FREE_BLOCKS_FORGET);
}
ext4_free_blocks(handle, inode, 0, le32_to_cpu(where[num].key),
- blks, 0);
+ blks, fb_flags);
return err;
}
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 3c27377..fa2fcf2 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4635,7 +4635,7 @@ do_more:
}
sb->s_dirt = 1;
error_return:
- if (freed)
+ if (!(flags & EXT4_FREE_BLOCKS_NOQUOTA) && freed)
dquot_free_block(inode, freed);
brelse(bitmap_bh);
ext4_std_error(sb, err);
--
1.6.6.1
