ext4: add self-testing infrastructure to do a sanity check
This commit adds a self-testing infrastructure like extent tree does to
do a sanity check for extent status tree. After status tree is as a
extent cache, we'd better to make sure that it caches right result.
After applied this commit, we will get a lot of messages when we run
xfstests as below.
...
kernel: ES len assertation failed for inode: 230 retval 1 != map->m_len
3 in ext4_map_blocks (allocation)
...
kernel: ES cache assertation failed for inode: 230 es_cached ex
[974/2/4781/20] != found ex [974/1/4781/1000]
...
kernel: ES insert assertation failed for inode: 635 ex_status
[0/45/21388/w] != es_status [44/1/21432/u]
...
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 95a0c62..3186a43 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -482,6 +482,58 @@
return num;
}
+#ifdef ES_AGGRESSIVE_TEST
+static void ext4_map_blocks_es_recheck(handle_t *handle,
+ struct inode *inode,
+ struct ext4_map_blocks *es_map,
+ struct ext4_map_blocks *map,
+ int flags)
+{
+ int retval;
+
+ map->m_flags = 0;
+ /*
+ * There is a race window that the result is not the same.
+ * e.g. xfstests #223 when dioread_nolock enables. The reason
+ * is that we lookup a block mapping in extent status tree with
+ * out taking i_data_sem. So at the time the unwritten extent
+ * could be converted.
+ */
+ if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
+ down_read((&EXT4_I(inode)->i_data_sem));
+ if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
+ retval = ext4_ext_map_blocks(handle, inode, map, flags &
+ EXT4_GET_BLOCKS_KEEP_SIZE);
+ } else {
+ retval = ext4_ind_map_blocks(handle, inode, map, flags &
+ EXT4_GET_BLOCKS_KEEP_SIZE);
+ }
+ if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
+ up_read((&EXT4_I(inode)->i_data_sem));
+ /*
+ * Clear EXT4_MAP_FROM_CLUSTER and EXT4_MAP_BOUNDARY flag
+ * because it shouldn't be marked in es_map->m_flags.
+ */
+ map->m_flags &= ~(EXT4_MAP_FROM_CLUSTER | EXT4_MAP_BOUNDARY);
+
+ /*
+ * We don't check m_len because extent will be collpased in status
+ * tree. So the m_len might not equal.
+ */
+ if (es_map->m_lblk != map->m_lblk ||
+ es_map->m_flags != map->m_flags ||
+ es_map->m_pblk != map->m_pblk) {
+ printk("ES cache assertation failed for inode: %lu "
+ "es_cached ex [%d/%d/%llu/%x] != "
+ "found ex [%d/%d/%llu/%x] retval %d flags %x\n",
+ inode->i_ino, es_map->m_lblk, es_map->m_len,
+ es_map->m_pblk, es_map->m_flags, map->m_lblk,
+ map->m_len, map->m_pblk, map->m_flags,
+ retval, flags);
+ }
+}
+#endif /* ES_AGGRESSIVE_TEST */
+
/*
* The ext4_map_blocks() function tries to look up the requested blocks,
* and returns if the blocks are already mapped.
@@ -509,6 +561,11 @@
{
struct extent_status es;
int retval;
+#ifdef ES_AGGRESSIVE_TEST
+ struct ext4_map_blocks orig_map;
+
+ memcpy(&orig_map, map, sizeof(*map));
+#endif
map->m_flags = 0;
ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
@@ -531,6 +588,10 @@
} else {
BUG_ON(1);
}
+#ifdef ES_AGGRESSIVE_TEST
+ ext4_map_blocks_es_recheck(handle, inode, map,
+ &orig_map, flags);
+#endif
goto found;
}
@@ -551,6 +612,15 @@
int ret;
unsigned long long status;
+#ifdef ES_AGGRESSIVE_TEST
+ if (retval != map->m_len) {
+ printk("ES len assertation failed for inode: %lu "
+ "retval %d != map->m_len %d "
+ "in %s (lookup)\n", inode->i_ino, retval,
+ map->m_len, __func__);
+ }
+#endif
+
status = map->m_flags & EXT4_MAP_UNWRITTEN ?
EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) &&
@@ -643,6 +713,15 @@
int ret;
unsigned long long status;
+#ifdef ES_AGGRESSIVE_TEST
+ if (retval != map->m_len) {
+ printk("ES len assertation failed for inode: %lu "
+ "retval %d != map->m_len %d "
+ "in %s (allocation)\n", inode->i_ino, retval,
+ map->m_len, __func__);
+ }
+#endif
+
status = map->m_flags & EXT4_MAP_UNWRITTEN ?
EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) &&
@@ -1768,6 +1847,11 @@
struct extent_status es;
int retval;
sector_t invalid_block = ~((sector_t) 0xffff);
+#ifdef ES_AGGRESSIVE_TEST
+ struct ext4_map_blocks orig_map;
+
+ memcpy(&orig_map, map, sizeof(*map));
+#endif
if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es))
invalid_block = ~0;
@@ -1809,6 +1893,9 @@
else
BUG_ON(1);
+#ifdef ES_AGGRESSIVE_TEST
+ ext4_map_blocks_es_recheck(NULL, inode, map, &orig_map, 0);
+#endif
return retval;
}
@@ -1873,6 +1960,15 @@
int ret;
unsigned long long status;
+#ifdef ES_AGGRESSIVE_TEST
+ if (retval != map->m_len) {
+ printk("ES len assertation failed for inode: %lu "
+ "retval %d != map->m_len %d "
+ "in %s (lookup)\n", inode->i_ino, retval,
+ map->m_len, __func__);
+ }
+#endif
+
status = map->m_flags & EXT4_MAP_UNWRITTEN ?
EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
ret = ext4_es_insert_extent(inode, map->m_lblk, map->m_len,