[uml-devel] [PATCH 5/5] uml: remove empty hostfs_truncate method

[Paolo 'B. G. <bla...@ya...>]

From: Paolo 'Blaisorblade' Giarrusso <bla...@ya...>

Calling truncate() on hostfs spits a kernel warning "Something isn't implemented
here", but it still works fine.

Indeed, hostfs i_op->truncate doesn't do anything. But hostfs_setattr() ->
set_attr() correctly detects ATTR_SIZE and calls truncate() on the host. So we
should be safe (using ftruncate() may be better, in case the file is unlinked on
the host, but we aren't sure to have the file open for writing, and reopening it
would cause the same races; plus nobody should expect UML to be so careful).

So, the warning is wrong, because the current implementation is working. Al, am
I correct, and can the warning be therefore dropped?

CC: Al Viro <vi...@ze...>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <bla...@ya...>
---

 fs/hostfs/hostfs_kern.c |    7 -------
 1 files changed, 0 insertions(+), 7 deletions(-)

diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -793,11 +793,6 @@ int hostfs_rename(struct inode *from_ino
 	return(err);
 }
 
-void hostfs_truncate(struct inode *ino)
-{
-	not_implemented();
-}
-
 int hostfs_permission(struct inode *ino, int desired, struct nameidata *nd)
 {
 	char *name;
@@ -894,7 +889,6 @@ static struct inode_operations hostfs_io
 	.rmdir		= hostfs_rmdir,
 	.mknod		= hostfs_mknod,
 	.rename		= hostfs_rename,
-	.truncate	= hostfs_truncate,
 	.permission	= hostfs_permission,
 	.setattr	= hostfs_setattr,
 	.getattr	= hostfs_getattr,
@@ -910,7 +904,6 @@ static struct inode_operations hostfs_di
 	.rmdir		= hostfs_rmdir,
 	.mknod		= hostfs_mknod,
 	.rename		= hostfs_rename,
-	.truncate	= hostfs_truncate,
 	.permission	= hostfs_permission,
 	.setattr	= hostfs_setattr,
 	.getattr	= hostfs_getattr,