[Devel] [PATCH RHEL7 COMMIT] ms/ext4: allow ext4_ext_truncate() to return an error

[Vasily Averin]

The commit is pushed to "branch-rh7-3.10.0-1160.11.1.vz7.172.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-1160.11.1.vz7.172.12
------>
commit f037eb9b180fd8573dc517cf2ffdfdd2eeb6ce7a
Author: Theodore Ts'o <tytso at mit.edu>
Date:   Fri Feb 5 14:30:04 2021 +0300

    ms/ext4: allow ext4_ext_truncate() to return an error
    
    Return errors to the caller instead of declaring the file system
    corrupted.
    
    Signed-off-by: Theodore Ts'o <tytso at mit.edu>
    Reviewed-by: Jan Kara <jack at suse.cz>
    
    (cherry picked from commit d0abb36db44faaf8f8aa148ca206fe2404042dec)
    Signed-off-by: Konstantin Khorenko <khorenko at virtuozzo.com>
---
 fs/ext4/ext4.h    |  2 +-
 fs/ext4/extents.c | 15 +++++++--------
 fs/ext4/inode.c   |  4 +++-
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 10df0e7..ad64168 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2848,7 +2848,7 @@ extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 			       struct ext4_map_blocks *map, int flags);
-extern void ext4_ext_truncate(handle_t *, struct inode *);
+extern int ext4_ext_truncate(handle_t *, struct inode *);
 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
 				 ext4_lblk_t end);
 extern void ext4_ext_init(struct super_block *);
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index cb0d9b6..b059276 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4660,7 +4660,7 @@ out2:
 	return err ? err : allocated;
 }
 
-void ext4_ext_truncate(handle_t *handle, struct inode *inode)
+int ext4_ext_truncate(handle_t *handle, struct inode *inode)
 {
 	struct super_block *sb = inode->i_sb;
 	ext4_lblk_t last_block;
@@ -4674,7 +4674,9 @@ void ext4_ext_truncate(handle_t *handle, struct inode *inode)
 
 	/* we have to know where to truncate from in crash case */
 	EXT4_I(inode)->i_disksize = inode->i_size;
-	ext4_mark_inode_dirty(handle, inode);
+	err = ext4_mark_inode_dirty(handle, inode);
+	if (err)
+		return err;
 
 	last_block = (inode->i_size + sb->s_blocksize - 1)
 			>> EXT4_BLOCK_SIZE_BITS(sb);
@@ -4686,12 +4688,9 @@ retry:
 		congestion_wait(BLK_RW_ASYNC, HZ/50);
 		goto retry;
 	}
-	if (err) {
-		ext4_std_error(inode->i_sb, err);
-		return;
-	}
-	err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
-	ext4_std_error(inode->i_sb, err);
+	if (err)
+		return err;
+	return ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
 }
 
 static int ext4_convert_unwritten(struct inode *inode, loff_t offset,
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index bdd55a9..6489d55 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4130,11 +4130,13 @@ int ext4_truncate(struct inode *inode)
 	ext4_discard_preallocations(inode);
 
 	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
-		ext4_ext_truncate(handle, inode);
+		err = ext4_ext_truncate(handle, inode);
 	else
 		ext4_ind_truncate(handle, inode);
 
 	up_write(&ei->i_data_sem);
+	if (err)
+		goto out_stop;
 
 	if (IS_SYNC(inode))
 		ext4_handle_sync(handle);