Commit 17ff7856 authored by Mark Fasheh's avatar Mark Fasheh Committed by Linus Torvalds
Browse files

[PATCH] r/o bind mounts: clean up OCFS2 nlink handling 



OCFS2 does some operations on i_nlink, then reverts them if some of its
operations fail to complete.  This does not fit in well with the
drop_nlink() logic where we expect i_nlink to stay at zero once it gets
there.

So, delay all of the nlink operations until we're sure that the operations
have completed.  Also, introduce a small helper to check whether an inode
has proper "unlinkable" i_nlink counts no matter whether it is a directory
or regular inode.

This patch is broken out from the others because it does contain some
logical changes.

Signed-off-by: default avatarDave Hansen <haveblue@us.ibm.com>
Signed-off-by: default avatarMark Fasheh <mark.fasheh@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent d8c76e6f

fs/ocfs2/namei.c

+19 −20
Original line number Diff line number Diff line
@@ -795,11 +795,23 @@ static int ocfs2_remote_dentry_delete(struct dentry *dentry) 
	return ret;

}



static inline int inode_is_unlinkable(struct inode *inode)

{

	if (S_ISDIR(inode->i_mode)) {

		if (inode->i_nlink == 2)

			return 1;

		return 0;

	}



	if (inode->i_nlink == 1)

		return 1;

	return 0;

}



static int ocfs2_unlink(struct inode *dir,

			struct dentry *dentry)

{

	int status;

	unsigned int saved_nlink = 0;

	struct inode *inode = dentry->d_inode;

	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);

	u64 blkno;
@@ -874,16 +886,6 @@ static int ocfs2_unlink(struct inode *dir, 
		}

	}



	/* There are still a few steps left until we can consider the

	 * unlink to have succeeded. Save off nlink here before

	 * modification so we can set it back in case we hit an issue

	 * before commit. */

	saved_nlink = inode->i_nlink;

	if (S_ISDIR(inode->i_mode))

		inode->i_nlink = 0;

	else

		inode->i_nlink--;



	status = ocfs2_remote_dentry_delete(dentry);

	if (status < 0) {

		/* This vote should succeed under all normal
@@ -892,7 +894,7 @@ static int ocfs2_unlink(struct inode *dir, 
		goto leave;

	}



	if (!inode->i_nlink) {

	if (inode_is_unlinkable(inode)) {

		status = ocfs2_prepare_orphan_dir(osb, handle, inode,

						  orphan_name,

						  &orphan_entry_bh);
@@ -919,7 +921,7 @@ static int ocfs2_unlink(struct inode *dir, 


	fe = (struct ocfs2_dinode *) fe_bh->b_data;



	if (!inode->i_nlink) {

	if (inode_is_unlinkable(inode)) {

		status = ocfs2_orphan_add(osb, handle, inode, fe, orphan_name,

					  orphan_entry_bh);

		if (status < 0) {
@@ -935,10 +937,10 @@ static int ocfs2_unlink(struct inode *dir, 
		goto leave;

	}



	/* We can set nlink on the dinode now. clear the saved version

	 * so that it doesn't get set later. */

	if (S_ISDIR(inode->i_mode))

		drop_nlink(inode);

	drop_nlink(inode);

	fe->i_links_count = cpu_to_le16(inode->i_nlink);

	saved_nlink = 0;



	status = ocfs2_journal_dirty(handle, fe_bh);

	if (status < 0) {
@@ -947,7 +949,7 @@ static int ocfs2_unlink(struct inode *dir, 
	}



	if (S_ISDIR(inode->i_mode)) {

		dir->i_nlink--;

		drop_nlink(dir);

		status = ocfs2_mark_inode_dirty(handle, dir,

						parent_node_bh);

		if (status < 0) {
@@ -957,9 +959,6 @@ static int ocfs2_unlink(struct inode *dir, 
	}



leave:

	if (status < 0 && saved_nlink)

		inode->i_nlink = saved_nlink;



	if (handle)

		ocfs2_commit_trans(handle);

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