ext4: Replace BUG_ON() with ext4_error() in move_extents.c
Replace BUG_ON calls with a call to ext4_error()
to print an error message if EXT4_IOC_MOVE_EXT failed
with some kind of reasons. This will help to debug.
Ted pointed this out, thanks.
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
index e4bd87614..2258560 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -128,6 +128,31 @@
}
/**
+ * mext_check_null_inode - NULL check for two inodes
+ *
+ * If inode1 or inode2 is NULL, return -EIO. Otherwise, return 0.
+ */
+static int
+mext_check_null_inode(struct inode *inode1, struct inode *inode2,
+ const char *function)
+{
+ int ret = 0;
+
+ if (inode1 == NULL) {
+ ext4_error(inode2->i_sb, function,
+ "Both inodes should not be NULL: "
+ "inode1 NULL inode2 %lu", inode2->i_ino);
+ ret = -EIO;
+ } else if (inode2 == NULL) {
+ ext4_error(inode1->i_sb, function,
+ "Both inodes should not be NULL: "
+ "inode1 %lu inode2 NULL", inode1->i_ino);
+ ret = -EIO;
+ }
+ return ret;
+}
+
+/**
* mext_double_down_read - Acquire two inodes' read semaphore
*
* @orig_inode: original inode structure
@@ -139,8 +164,6 @@
{
struct inode *first = orig_inode, *second = donor_inode;
- BUG_ON(orig_inode == NULL || donor_inode == NULL);
-
/*
* Use the inode number to provide the stable locking order instead
* of its address, because the C language doesn't guarantee you can
@@ -167,8 +190,6 @@
{
struct inode *first = orig_inode, *second = donor_inode;
- BUG_ON(orig_inode == NULL || donor_inode == NULL);
-
/*
* Use the inode number to provide the stable locking order instead
* of its address, because the C language doesn't guarantee you can
@@ -193,8 +214,6 @@
static void
mext_double_up_read(struct inode *orig_inode, struct inode *donor_inode)
{
- BUG_ON(orig_inode == NULL || donor_inode == NULL);
-
up_read(&EXT4_I(orig_inode)->i_data_sem);
up_read(&EXT4_I(donor_inode)->i_data_sem);
}
@@ -209,8 +228,6 @@
static void
mext_double_up_write(struct inode *orig_inode, struct inode *donor_inode)
{
- BUG_ON(orig_inode == NULL || donor_inode == NULL);
-
up_write(&EXT4_I(orig_inode)->i_data_sem);
up_write(&EXT4_I(donor_inode)->i_data_sem);
}
@@ -534,7 +551,15 @@
* oext |-----------|
* new_ext |-------|
*/
- BUG_ON(le32_to_cpu(oext->ee_block) + oext_alen - 1 < new_ext_end);
+ if (le32_to_cpu(oext->ee_block) + oext_alen - 1 < new_ext_end) {
+ ext4_error(orig_inode->i_sb, __func__,
+ "new_ext_end(%u) should be less than or equal to "
+ "oext->ee_block(%u) + oext_alen(%d) - 1",
+ new_ext_end, le32_to_cpu(oext->ee_block),
+ oext_alen);
+ ret = -EIO;
+ goto out;
+ }
/*
* Case: new_ext is smaller than original extent
@@ -558,6 +583,7 @@
ret = mext_insert_extents(handle, orig_inode, orig_path, o_start,
o_end, &start_ext, &new_ext, &end_ext);
+out:
return ret;
}
@@ -668,7 +694,20 @@
/* Loop for the donor extents */
while (1) {
/* The extent for donor must be found. */
- BUG_ON(!dext || donor_off != le32_to_cpu(tmp_dext.ee_block));
+ if (!dext) {
+ ext4_error(donor_inode->i_sb, __func__,
+ "The extent for donor must be found");
+ err = -EIO;
+ goto out;
+ } else if (donor_off != le32_to_cpu(tmp_dext.ee_block)) {
+ ext4_error(donor_inode->i_sb, __func__,
+ "Donor offset(%u) and the first block of donor "
+ "extent(%u) should be equal",
+ donor_off,
+ le32_to_cpu(tmp_dext.ee_block));
+ err = -EIO;
+ goto out;
+ }
/* Set donor extent to orig extent */
err = mext_leaf_block(handle, orig_inode,
@@ -1050,18 +1089,23 @@
* @inode1: the inode structure
* @inode2: the inode structure
*
- * Lock two inodes' i_mutex by i_ino order. This function is moved from
- * fs/inode.c.
+ * Lock two inodes' i_mutex by i_ino order.
+ * If inode1 or inode2 is NULL, return -EIO. Otherwise, return 0.
*/
-static void
+static int
mext_inode_double_lock(struct inode *inode1, struct inode *inode2)
{
- if (inode1 == NULL || inode2 == NULL || inode1 == inode2) {
- if (inode1)
- mutex_lock(&inode1->i_mutex);
- else if (inode2)
- mutex_lock(&inode2->i_mutex);
- return;
+ int ret = 0;
+
+ BUG_ON(inode1 == NULL && inode2 == NULL);
+
+ ret = mext_check_null_inode(inode1, inode2, __func__);
+ if (ret < 0)
+ goto out;
+
+ if (inode1 == inode2) {
+ mutex_lock(&inode1->i_mutex);
+ goto out;
}
if (inode1->i_ino < inode2->i_ino) {
@@ -1071,6 +1115,9 @@
mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT);
mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD);
}
+
+out:
+ return ret;
}
/**
@@ -1079,17 +1126,28 @@
* @inode1: the inode that is released first
* @inode2: the inode that is released second
*
- * This function is moved from fs/inode.c.
+ * If inode1 or inode2 is NULL, return -EIO. Otherwise, return 0.
*/
-static void
+static int
mext_inode_double_unlock(struct inode *inode1, struct inode *inode2)
{
+ int ret = 0;
+
+ BUG_ON(inode1 == NULL && inode2 == NULL);
+
+ ret = mext_check_null_inode(inode1, inode2, __func__);
+ if (ret < 0)
+ goto out;
+
if (inode1)
mutex_unlock(&inode1->i_mutex);
if (inode2 && inode2 != inode1)
mutex_unlock(&inode2->i_mutex);
+
+out:
+ return ret;
}
/**
@@ -1146,21 +1204,23 @@
ext4_lblk_t block_end, seq_start, add_blocks, file_end, seq_blocks = 0;
ext4_lblk_t rest_blocks;
pgoff_t orig_page_offset = 0, seq_end_page;
- int ret, depth, last_extent = 0;
+ int ret1, ret2, depth, last_extent = 0;
int blocks_per_page = PAGE_CACHE_SIZE >> orig_inode->i_blkbits;
int data_offset_in_page;
int block_len_in_page;
int uninit;
/* protect orig and donor against a truncate */
- mext_inode_double_lock(orig_inode, donor_inode);
+ ret1 = mext_inode_double_lock(orig_inode, donor_inode);
+ if (ret1 < 0)
+ return ret1;
mext_double_down_read(orig_inode, donor_inode);
/* Check the filesystem environment whether move_extent can be done */
- ret = mext_check_arguments(orig_inode, donor_inode, orig_start,
+ ret1 = mext_check_arguments(orig_inode, donor_inode, orig_start,
donor_start, &len, *moved_len);
mext_double_up_read(orig_inode, donor_inode);
- if (ret)
+ if (ret1)
goto out2;
file_end = (i_size_read(orig_inode) - 1) >> orig_inode->i_blkbits;
@@ -1168,19 +1228,19 @@
if (file_end < block_end)
len -= block_end - file_end;
- ret = get_ext_path(orig_inode, block_start, &orig_path);
+ ret1 = get_ext_path(orig_inode, block_start, &orig_path);
if (orig_path == NULL)
goto out2;
/* Get path structure to check the hole */
- ret = get_ext_path(orig_inode, block_start, &holecheck_path);
+ ret1 = get_ext_path(orig_inode, block_start, &holecheck_path);
if (holecheck_path == NULL)
goto out;
depth = ext_depth(orig_inode);
ext_cur = holecheck_path[depth].p_ext;
if (ext_cur == NULL) {
- ret = -EINVAL;
+ ret1 = -EINVAL;
goto out;
}
@@ -1193,13 +1253,13 @@
last_extent = mext_next_extent(orig_inode,
holecheck_path, &ext_cur);
if (last_extent < 0) {
- ret = last_extent;
+ ret1 = last_extent;
goto out;
}
last_extent = mext_next_extent(orig_inode, orig_path,
&ext_dummy);
if (last_extent < 0) {
- ret = last_extent;
+ ret1 = last_extent;
goto out;
}
}
@@ -1209,7 +1269,7 @@
if (le32_to_cpu(ext_cur->ee_block) > block_end) {
ext4_debug("ext4 move extent: The specified range of file "
"may be the hole\n");
- ret = -EINVAL;
+ ret1 = -EINVAL;
goto out;
}
@@ -1229,7 +1289,7 @@
last_extent = mext_next_extent(orig_inode, holecheck_path,
&ext_cur);
if (last_extent < 0) {
- ret = last_extent;
+ ret1 = last_extent;
break;
}
add_blocks = ext4_ext_get_actual_len(ext_cur);
@@ -1281,16 +1341,23 @@
while (orig_page_offset <= seq_end_page) {
/* Swap original branches with new branches */
- ret = move_extent_per_page(o_filp, donor_inode,
+ ret1 = move_extent_per_page(o_filp, donor_inode,
orig_page_offset,
data_offset_in_page,
block_len_in_page, uninit);
- if (ret < 0)
+ if (ret1 < 0)
goto out;
orig_page_offset++;
/* Count how many blocks we have exchanged */
*moved_len += block_len_in_page;
- BUG_ON(*moved_len > len);
+ if (*moved_len > len) {
+ ext4_error(orig_inode->i_sb, __func__,
+ "We replaced blocks too much! "
+ "sum of replaced: %llu requested: %llu",
+ *moved_len, len);
+ ret1 = -EIO;
+ goto out;
+ }
data_offset_in_page = 0;
rest_blocks -= block_len_in_page;
@@ -1303,7 +1370,7 @@
/* Decrease buffer counter */
if (holecheck_path)
ext4_ext_drop_refs(holecheck_path);
- ret = get_ext_path(orig_inode, seq_start, &holecheck_path);
+ ret1 = get_ext_path(orig_inode, seq_start, &holecheck_path);
if (holecheck_path == NULL)
break;
depth = holecheck_path->p_depth;
@@ -1311,7 +1378,7 @@
/* Decrease buffer counter */
if (orig_path)
ext4_ext_drop_refs(orig_path);
- ret = get_ext_path(orig_inode, seq_start, &orig_path);
+ ret1 = get_ext_path(orig_inode, seq_start, &orig_path);
if (orig_path == NULL)
break;
@@ -1330,10 +1397,12 @@
kfree(holecheck_path);
}
out2:
- mext_inode_double_unlock(orig_inode, donor_inode);
+ ret2 = mext_inode_double_unlock(orig_inode, donor_inode);
- if (ret)
- return ret;
+ if (ret1)
+ return ret1;
+ else if (ret2)
+ return ret2;
return 0;
}