Commit f8713576 authored by David Howells's avatar David Howells Committed by Linus Torvalds
Browse files

[PATCH] VFS: Fix an error in unused dentry counting 



With Vasily Averin <vvs@sw.ru>

Fix an error in unused dentry counting in shrink_dcache_for_umount_subtree()
in which the count is modified without the dcache_lock held.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Cc: Vasily Averin <vvs@sw.ru>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 6eac3f93

fs/dcache.c

+8 −2
Original line number Diff line number Diff line
@@ -557,6 +557,7 @@ repeat: 
static void shrink_dcache_for_umount_subtree(struct dentry *dentry)

{

	struct dentry *parent;

	unsigned detached = 0;



	BUG_ON(!IS_ROOT(dentry));
@@ -621,7 +622,7 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) 
				atomic_dec(&parent->d_count);



			list_del(&dentry->d_u.d_child);

			dentry_stat.nr_dentry--;	/* For d_free, below */

			detached++;



			inode = dentry->d_inode;

			if (inode) {
@@ -639,7 +640,7 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) 
			 * otherwise we ascend to the parent and move to the

			 * next sibling if there is one */

			if (!parent)

				return;

				goto out;



			dentry = parent;
@@ -648,6 +649,11 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) 
		dentry = list_entry(dentry->d_subdirs.next,

				    struct dentry, d_u.d_child);

	}

out:

	/* several dentries were freed, need to correct nr_dentry */

	spin_lock(&dcache_lock);

	dentry_stat.nr_dentry -= detached;

	spin_unlock(&dcache_lock);

}



/*

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