[PATCH v2] ext4: Convert ext4 to new truncate calling convention

[Jan Kara <jack@suse.cz>]

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>
---
 fs/ext4/file.c  |    1 -
 fs/ext4/inode.c |    4 +---
 2 files changed, 1 insertions(+), 4 deletions(-)

 Ted, this patch should finish necessary conversion of ext4 to new truncate
calling sequence.

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 7b80d54..2c09723 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 fe37371..1f8e839 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3513,7 +3513,7 @@ 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))
@@ -4380,8 +4380,6 @@ 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))
-- 
1.7.1