Commit 1b947463 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Al Viro
Browse files

cifs: truncate fallout 



Remove the calls to inode_newsize_ok given that we already did it as
part of inode_change_ok in the beginning of cifs_setattr_(no)unix.

No need to call ->truncate if cifs doesn't have one, so remove the
explicit call in cifs_vmtruncate, and replace the calls to vmtruncate
with truncate_setsize which is vmtruncate minus inode_newsize_ok
and the call to ->truncate.

Rename cifs_vmtruncate to cifs_setsize to match the new calling conventions.

Question 1:  why does cifs do the pagecache munging and i_size update twice
	for each setattr call, once opencoded in cifs_vmtruncate, and once
	using the VFS helpers?
Question 2: what is supposed to be protected by i_lock in cifs_vmtruncate?
	Do we need it around the call to inode_change_ok?

[AV: fixed build breakage]

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent e566d48c

fs/cifs/inode.c

+7 −23
Original line number Diff line number Diff line
@@ -1679,26 +1679,16 @@ static int cifs_truncate_page(struct address_space *mapping, loff_t from) 
	return rc;

}



static int cifs_vmtruncate(struct inode *inode, loff_t offset)

static void cifs_setsize(struct inode *inode, loff_t offset)

{

	loff_t oldsize;

	int err;



	spin_lock(&inode->i_lock);

	err = inode_newsize_ok(inode, offset);

	if (err) {

		spin_unlock(&inode->i_lock);

		goto out;

	}



	oldsize = inode->i_size;

	i_size_write(inode, offset);

	spin_unlock(&inode->i_lock);



	truncate_pagecache(inode, oldsize, offset);

	if (inode->i_op->truncate)

		inode->i_op->truncate(inode);

out:

	return err;

}



static int
@@ -1771,7 +1761,7 @@ cifs_set_file_size(struct inode *inode, struct iattr *attrs, 


	if (rc == 0) {

		cifsInode->server_eof = attrs->ia_size;

		rc = cifs_vmtruncate(inode, attrs->ia_size);

		cifs_setsize(inode, attrs->ia_size);

		cifs_truncate_page(inode->i_mapping, inode->i_size);

	}
@@ -1891,11 +1881,8 @@ cifs_setattr_unix(struct dentry *direntry, struct iattr *attrs) 
		goto out;



	if ((attrs->ia_valid & ATTR_SIZE) &&

	    attrs->ia_size != i_size_read(inode)) {

		rc = vmtruncate(inode, attrs->ia_size);

		if (rc)

			goto out;

	}

	    attrs->ia_size != i_size_read(inode))

		truncate_setsize(inode, attrs->ia_size);



	setattr_copy(inode, attrs);

	mark_inode_dirty(inode);
@@ -2050,11 +2037,8 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs) 
		goto cifs_setattr_exit;



	if ((attrs->ia_valid & ATTR_SIZE) &&

	    attrs->ia_size != i_size_read(inode)) {

		rc = vmtruncate(inode, attrs->ia_size);

		if (rc)

			goto cifs_setattr_exit;

	}

	    attrs->ia_size != i_size_read(inode))

		truncate_setsize(inode, attrs->ia_size);



	setattr_copy(inode, attrs);

	mark_inode_dirty(inode);

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