ext4: Convert ext4 to new truncate calling convention

Trivial conversion.  Fixup one error handling case calling vmtruncate()
and remove ->truncate callback. We also fix a bug that IS_IMMUTABLE and
IS_APPEND files could not be truncated during failed writes. In fact, the
test can be completely removed as upper layers do necessary permission
checks for truncate in do_sys_[f]truncate() and may_open() anyway.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

2 files changed, 1 insertions, 4 deletions

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 7b80d543b89e..2c0972322009 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -272,7 +272,6 @@ const struct file_operations ext4_file_operations = {
 };
 
 const struct inode_operations ext4_file_inode_operations = {
-        .truncate       = ext4_truncate,
         .setattr        = ext4_setattr,
         .getattr        = ext4_getattr,
 #ifdef CONFIG_EXT4_FS_XATTR
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 65576c02c6f5..50d0e9c64584 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3511,7 +3511,7 @@ retry:
                         loff_t end = offset + iov_length(iov, nr_segs);
 
                         if (end > isize)
-                                vmtruncate(inode, isize);
+                                ext4_truncate_failed_write(inode);
                 }
         }
         if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
@@ -4407,8 +4407,6 @@ static void ext4_free_branches(handle_t *handle, struct inode *inode,
 
 int ext4_can_truncate(struct inode *inode)
 {
-        if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
-                return 0;
         if (S_ISREG(inode->i_mode))
                 return 1;
         if (S_ISDIR(inode->i_mode))