As a result, if the system cashed during or shortly after the
extents migration, and the released indirect blocks get reused as
data blocks, the journal replay would corrupt the data blocks.
With this new patch, fixing this bug was as simple as adding the
EXT4_FREE_BLOCKS_FORGET flags to the call to ext4_free_blocks().
Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx>
---
fs/ext4/ext4.h | 10 +++++-
fs/ext4/extents.c | 24 ++++++---------
fs/ext4/inode.c | 67 +++++++++++++++
+--------------------------
fs/ext4/mballoc.c | 49 +++++++++++++++++++++++--------
fs/ext4/migrate.c | 23 ++++++++++----
fs/ext4/xattr.c | 8 +++--
include/trace/events/ext4.h | 16 ++++++----
7 files changed, 109 insertions(+), 88 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 210e1b5..4cfc2f0 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -376,6 +376,12 @@ struct ext4_new_group_data {
EXT4_GET_BLOCKS_DIO_CREATE_EXT)
/*
+ * Flags used by ext4_free_blocks
+ */
+#define EXT4_FREE_BLOCKS_METADATA 0x0001
+#define EXT4_FREE_BLOCKS_FORGET 0x0002
+
+/*
* ioctl commands
*/
#define EXT4_IOC_GETFLAGS FS_IOC_GETFLAGS
@@ -1384,8 +1390,8 @@ extern void ext4_discard_preallocations(struct
inode *);
extern int __init init_ext4_mballoc(void);
extern void exit_ext4_mballoc(void);
extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
- ext4_fsblk_t block, unsigned long count,
- int metadata);
+ struct buffer_head *bh, ext4_fsblk_t block,
+ unsigned long count, int flags);
extern int ext4_mb_add_groupinfo(struct super_block *sb,
ext4_group_t i, struct ext4_group_desc *desc);
extern int ext4_mb_get_buddy_cache_lock(struct super_block *,
ext4_group_t);
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 74dcff8..2c4a932 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -1007,7 +1007,8 @@ cleanup:
for (i = 0; i < depth; i++) {
if (!ablocks[i])
continue;
- ext4_free_blocks(handle, inode, ablocks[i], 1, 1);
+ ext4_free_blocks(handle, inode, 0, ablocks[i], 1,
+ EXT4_FREE_BLOCKS_METADATA);
}
}
kfree(ablocks);
@@ -1957,7 +1958,6 @@ errout:
static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path)
{
- struct buffer_head *bh;
int err;
ext4_fsblk_t leaf;
@@ -1973,9 +1973,8 @@ static int ext4_ext_rm_idx(handle_t *handle,
struct inode *inode,
if (err)
return err;
ext_debug("index is empty, remove it, free block %llu\n", leaf);
- bh = sb_find_get_block(inode->i_sb, leaf);
- ext4_forget(handle, 1, inode, bh, leaf);
- ext4_free_blocks(handle, inode, leaf, 1, 1);
+ ext4_free_blocks(handle, inode, 0, leaf, 1,
+ EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
return err;
}
@@ -2042,12 +2041,11 @@ static int ext4_remove_blocks(handle_t
*handle, struct inode *inode,
struct ext4_extent *ex,
ext4_lblk_t from, ext4_lblk_t to)
{
- struct buffer_head *bh;
unsigned short ee_len = ext4_ext_get_actual_len(ex);
- int i, metadata = 0;
+ int flags = EXT4_FREE_BLOCKS_FORGET;
if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
- metadata = 1;
+ flags |= EXT4_FREE_BLOCKS_METADATA;
#ifdef EXTENTS_STATS
{
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
@@ -2072,11 +2070,7 @@ static int ext4_remove_blocks(handle_t
*handle, struct inode *inode,
num = le32_to_cpu(ex->ee_block) + ee_len - from;
start = ext_pblock(ex) + ee_len - num;
ext_debug("free last %u blocks starting %llu\n", num, start);
- for (i = 0; i < num; i++) {
- bh = sb_find_get_block(inode->i_sb, start + i);
- ext4_forget(handle, metadata, inode, bh, start + i);
- }
- ext4_free_blocks(handle, inode, start, num, metadata);
+ ext4_free_blocks(handle, inode, 0, start, num, flags);
} else if (from == le32_to_cpu(ex->ee_block)
&& to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n",
@@ -3319,8 +3313,8 @@ int ext4_ext_get_blocks(handle_t *handle,
struct inode *inode,
/* not a good idea to call discard here directly,
* but otherwise we'd need to call it every free() */
ext4_discard_preallocations(inode);
- ext4_free_blocks(handle, inode, ext_pblock(&newex),
- ext4_ext_get_actual_len(&newex), 0);
+ ext4_free_blocks(handle, inode, 0, ext_pblock(&newex),
+ ext4_ext_get_actual_len(&newex), 0);
goto out2;
}
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 72c6943..3b28e1f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -669,7 +669,7 @@ allocated:
return ret;
failed_out:
for (i = 0; i < index; i++)
- ext4_free_blocks(handle, inode, new_blocks[i], 1, 0);
+ ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, 0);
return ret;
}
@@ -765,20 +765,20 @@ 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);
for (i = 1; i <= n ; i++) {
- BUFFER_TRACE(branch[i].bh, "call jbd2_journal_forget");
/*
- * Note: is_metadata is 0 because branch[i].bh is
- * newly allocated, so there is no need to revoke the
- * block. If we do, it's harmless, but not necessary.
+ * 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_forget(handle, 0, inode, branch[i].bh,
- branch[i].bh->b_blocknr);
+ ext4_free_blocks(handle, inode, 0, new_blocks[i], 1,
+ EXT4_FREE_BLOCKS_FORGET);
}
- for (i = 0; i < indirect_blks; i++)
- ext4_free_blocks(handle, inode, new_blocks[i], 1, 0);
+ for (i = n+1; i < indirect_blks; i++)
+ ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, 0);
- ext4_free_blocks(handle, inode, new_blocks[i], num, 0);
+ ext4_free_blocks(handle, inode, 0, new_blocks[i], num, 0);
return err;
}
@@ -857,18 +857,16 @@ static int ext4_splice_branch(handle_t
*handle, struct inode *inode,
err_out:
for (i = 1; i <= num; i++) {
- BUFFER_TRACE(where[i].bh, "call jbd2_journal_forget");
/*
- * Note: is_metadata is 0 because branch[i].bh is
- * newly allocated, so there is no need to revoke the
- * block. If we do, it's harmless, but not necessary.
+ * 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_forget(handle, 0, inode, where[i].bh,
- where[i].bh->b_blocknr);
- ext4_free_blocks(handle, inode,
- le32_to_cpu(where[i-1].key), 1, 0);
+ ext4_free_blocks(handle, inode, where[i].bh, 0, 1,
+ EXT4_FREE_BLOCKS_FORGET);
}
- ext4_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks,
0);
+ ext4_free_blocks(handle, inode, 0, le32_to_cpu(where[num].key),
+ blks, 0);
return err;
}
@@ -4080,7 +4078,10 @@ static void ext4_clear_blocks(handle_t
*handle, struct inode *inode,
__le32 *last)
{
__le32 *p;
- int is_metadata = S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode);
+ int flags = EXT4_FREE_BLOCKS_FORGET;
+
+ if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
+ flags |= EXT4_FREE_BLOCKS_METADATA;
if (try_to_extend_transaction(handle, inode)) {
if (bh) {
@@ -4096,27 +4097,10 @@ static void ext4_clear_blocks(handle_t
*handle, struct inode *inode,
}
}
- /*
- * Any buffers which are on the journal will be in memory. We
- * find them on the hash table so jbd2_journal_revoke() will
- * run jbd2_journal_forget() on them. We've already detached
- * each block from the file, so bforget() in
- * jbd2_journal_forget() should be safe.
- *
- * AKPM: turn on bforget in jbd2_journal_forget()!!!
- */
- for (p = first; p < last; p++) {
- u32 nr = le32_to_cpu(*p);
- if (nr) {
- struct buffer_head *tbh;
-
- *p = 0;
- tbh = sb_find_get_block(inode->i_sb, nr);
- ext4_forget(handle, is_metadata, inode, tbh, nr);
- }
- }
+ for (p = first; p < last; p++)
+ *p = 0;
- ext4_free_blocks(handle, inode, block_to_free, count, is_metadata);
+ ext4_free_blocks(handle, inode, 0, block_to_free, count, flags);
}
/**
@@ -4304,7 +4288,8 @@ static void ext4_free_branches(handle_t
*handle, struct inode *inode,
blocks_for_truncate(inode));
}
- ext4_free_blocks(handle, inode, nr, 1, 1);
+ ext4_free_blocks(handle, inode, 0, nr, 1,
+ EXT4_FREE_BLOCKS_METADATA);
if (parent_bh) {
/*
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 0dca90b..78de5d3 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4436,8 +4436,8 @@ ext4_mb_free_metadata(handle_t *handle, struct
ext4_buddy *e4b,
* @metadata: Are these metadata blocks
*/
void ext4_free_blocks(handle_t *handle, struct inode *inode,
- ext4_fsblk_t block, unsigned long count,
- int metadata)
+ struct buffer_head *bh, ext4_fsblk_t block,
+ unsigned long count, int flags)
{
struct buffer_head *bitmap_bh = NULL;
struct super_block *sb = inode->i_sb;
@@ -4454,15 +4454,12 @@ void ext4_free_blocks(handle_t *handle,
struct inode *inode,
int err = 0;
int ret;
- /*
- * We need to make sure we don't reuse the freed block until
- * after the transaction is committed, which we can do by
- * treating the block as metadata, below. We make an
- * exception if the inode is to be written in writeback mode
- * since writeback mode has weak data consistency guarantees.
- */
- if (!ext4_should_writeback_data(inode))
- metadata = 1;
+ if (bh) {
+ if (block)
+ BUG_ON(block != bh->b_blocknr);
+ else
+ block = bh->b_blocknr;
+ }
sbi = EXT4_SB(sb);
es = EXT4_SB(sb)->s_es;
@@ -4476,7 +4473,32 @@ void ext4_free_blocks(handle_t *handle,
struct inode *inode,
}
ext4_debug("freeing block %llu\n", block);
- trace_ext4_free_blocks(inode, block, count, metadata);
+ trace_ext4_free_blocks(inode, block, count, flags);
+
+ if (flags & EXT4_FREE_BLOCKS_FORGET) {
+ struct buffer_head *tbh = bh;
+ int i;
+
+ BUG_ON(bh && (count > 1));
+
+ for (i = 0; i < count; i++) {
+ if (!bh)
+ tbh = sb_find_get_block(inode->i_sb,
+ block + i);
+ ext4_forget(handle, flags & EXT4_FREE_BLOCKS_METADATA,
+ inode, tbh, block + i);
+ }
+ }
+
+ /*
+ * We need to make sure we don't reuse the freed block until
+ * after the transaction is committed, which we can do by
+ * treating the block as metadata, below. We make an
+ * exception if the inode is to be written in writeback mode
+ * since writeback mode has weak data consistency guarantees.
+ */
+ if (!ext4_should_writeback_data(inode))
+ flags |= EXT4_FREE_BLOCKS_METADATA;
ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
if (ac) {
@@ -4552,7 +4574,8 @@ do_more:
err = ext4_mb_load_buddy(sb, block_group, &e4b);
if (err)
goto error_return;
- if (metadata && ext4_handle_valid(handle)) {
+
+ if ((flags & EXT4_FREE_BLOCKS_METADATA) &&
ext4_handle_valid(handle)) {
struct ext4_free_data *new_entry;
/*
* blocks being freed are metadata. these blocks shouldn't
diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
index a93d5b8..d641e13 100644
--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -262,13 +262,17 @@ static int free_dind_blocks(handle_t *handle,
for (i = 0; i < max_entries; i++) {
if (tmp_idata[i]) {
extend_credit_for_blkdel(handle, inode);
- ext4_free_blocks(handle, inode,
- le32_to_cpu(tmp_idata[i]), 1, 1);
+ ext4_free_blocks(handle, inode, 0,
+ le32_to_cpu(tmp_idata[i]), 1,
+ EXT4_FREE_BLOCKS_METADATA |
+ EXT4_FREE_BLOCKS_FORGET);
}
}
put_bh(bh);
extend_credit_for_blkdel(handle, inode);
- ext4_free_blocks(handle, inode, le32_to_cpu(i_data), 1, 1);
+ ext4_free_blocks(handle, inode, 0, le32_to_cpu(i_data), 1,
+ EXT4_FREE_BLOCKS_METADATA |
+ EXT4_FREE_BLOCKS_FORGET);
return 0;
}
@@ -297,7 +301,9 @@ static int free_tind_blocks(handle_t *handle,
}
put_bh(bh);
extend_credit_for_blkdel(handle, inode);
- ext4_free_blocks(handle, inode, le32_to_cpu(i_data), 1, 1);
+ ext4_free_blocks(handle, inode, 0, le32_to_cpu(i_data), 1,
+ EXT4_FREE_BLOCKS_METADATA |
+ EXT4_FREE_BLOCKS_FORGET);
return 0;
}
@@ -308,8 +314,10 @@ static int free_ind_block(handle_t *handle,
struct inode *inode, __le32 *i_data)
/* ei->i_data[EXT4_IND_BLOCK] */
if (i_data[0]) {
extend_credit_for_blkdel(handle, inode);
- ext4_free_blocks(handle, inode,
- le32_to_cpu(i_data[0]), 1, 1);
+ ext4_free_blocks(handle, inode, 0,
+ le32_to_cpu(i_data[0]), 1,
+ EXT4_FREE_BLOCKS_METADATA |
+ EXT4_FREE_BLOCKS_FORGET);
}
/* ei->i_data[EXT4_DIND_BLOCK] */
@@ -419,7 +427,8 @@ static int free_ext_idx(handle_t *handle, struct
inode *inode,
}
put_bh(bh);
extend_credit_for_blkdel(handle, inode);
- ext4_free_blocks(handle, inode, block, 1, 1);
+ ext4_free_blocks(handle, inode, 0, block, 1,
+ EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
return retval;
}
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 0257019..910bf9a 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -482,9 +482,10 @@ ext4_xattr_release_block(handle_t *handle,
struct inode *inode,
ea_bdebug(bh, "refcount now=0; freeing");
if (ce)
mb_cache_entry_free(ce);
- ext4_free_blocks(handle, inode, bh->b_blocknr, 1, 1);
get_bh(bh);
- ext4_forget(handle, 1, inode, bh, bh->b_blocknr);
+ ext4_free_blocks(handle, inode, bh, 0, 1,
+ EXT4_FREE_BLOCKS_METADATA |
+ EXT4_FREE_BLOCKS_FORGET);
} else {
le32_add_cpu(&BHDR(bh)->h_refcount, -1);
error = ext4_handle_dirty_metadata(handle, inode, bh);
@@ -832,7 +833,8 @@ inserted:
new_bh = sb_getblk(sb, block);
if (!new_bh) {
getblk_failed:
- ext4_free_blocks(handle, inode, block, 1, 1);
+ ext4_free_blocks(handle, inode, 0, block, 1,
+ EXT4_FREE_BLOCKS_METADATA);
error = -EIO;
goto cleanup;
}
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index b390e1f..74f628b 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -650,30 +650,32 @@ TRACE_EVENT(ext4_allocate_blocks,
TRACE_EVENT(ext4_free_blocks,
TP_PROTO(struct inode *inode, __u64 block, unsigned long count,
- int metadata),
+ int flags),
- TP_ARGS(inode, block, count, metadata),
+ TP_ARGS(inode, block, count, flags),
TP_STRUCT__entry(
__field( dev_t, dev )
__field( ino_t, ino )
+ __field( umode_t, mode )
__field( __u64, block )
__field( unsigned long, count )
- __field( int, metadata )
-
+ __field( int, flags )
),
TP_fast_assign(
__entry->dev = inode->i_sb->s_dev;
__entry->ino = inode->i_ino;
+ __entry->mode = inode->i_mode;
__entry->block = block;
__entry->count = count;
- __entry->metadata = metadata;
+ __entry->flags = flags;
),
- TP_printk("dev %s ino %lu block %llu count %lu metadata %d",
+ TP_printk("dev %s ino %lu mode 0%o block %llu count %lu flags %d",
jbd2_dev_to_name(__entry->dev), (unsigned long) __entry->ino,
- __entry->block, __entry->count, __entry->metadata)
+ __entry->mode, __entry->block, __entry->count,
+ __entry->flags)
);
TRACE_EVENT(ext4_sync_file,
--
1.6.5.216.g5288a.dirty
