check ATTR_SIZE contraints in inode_change_ok

Make sure we check the truncate constraints early on in ->setattr by adding
those checks to inode_change_ok.  Also clean up and document inode_change_ok
to make this obvious.

As a fallout we don't have to call inode_newsize_ok from simple_setsize and
simplify it down to a truncate_setsize which doesn't return an error.  This
simplifies a lot of setattr implementations and means we use truncate_setsize
almost everywhere.  Get rid of fat_setsize now that it's trivial and mark
ext2_setsize static to make the calling convention obvious.

Keep the inode_newsize_ok in vmtruncate for now as all callers need an
audit for its removal anyway.

Note: setattr code in ecryptfs doesn't call inode_change_ok at all and
needs a deeper audit, but that is left for later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index 459d39d1ea0b..1b2426604fe3 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -169,13 +169,13 @@ int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
         mutex_unlock(&f->sem);
         jffs2_complete_reservation(c);
 
-        /* We have to do the simple_setsize() without f->sem held, since
+        /* We have to do the truncate_setsize() without f->sem held, since
            some pages may be locked and waiting for it in readpage().
            We are protected from a simultaneous write() extending i_size
            back past iattr->ia_size, because do_truncate() holds the
            generic inode semaphore. */
         if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size) {
-                simple_setsize(inode, iattr->ia_size);
+                truncate_setsize(inode, iattr->ia_size);
                 inode->i_blocks = (inode->i_size + 511) >> 9;
         }