From c42c7f7e698fa888abbd50eb9c8e328fff68914f Mon Sep 17 00:00:00 2001 From: Ian Kent Date: Tue, 15 Dec 2009 16:45:48 -0800 Subject: [PATCH 1/1] autofs4: eliminate d_unhashed in path walk checks We unhash the dentry (in a subsequent patch) in ->d_revalidate() in order to send mount requests to ->lookup(). But then we can not rely on d_unhased() to give reliable results because it may be called at any time by any code path. The d_unhashed() function is used by __simple_empty() in the path walking callbacks but autofs mount point dentrys should have no directories at all so a list_empty() on d_subdirs should be (and is) sufficient. Signed-off-by: Ian Kent Cc: Sage Weil Cc: Al Viro Cc: Andreas Dilger Cc: Christoph Hellwig Cc: Yehuda Saheh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/autofs4/root.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index 81700f4a19da..b6530f321adb 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -133,7 +133,7 @@ static int autofs4_dir_open(struct inode *inode, struct file *file) * it. */ spin_lock(&dcache_lock); - if (!d_mountpoint(dentry) && __simple_empty(dentry)) { + if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) { spin_unlock(&dcache_lock); return -ENOENT; } @@ -257,7 +257,7 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) * mount it again. */ if (ino->flags & AUTOFS_INF_PENDING || - (!d_mountpoint(dentry) && __simple_empty(dentry))) { + (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs))) { spin_unlock(&dcache_lock); spin_unlock(&sbi->fs_lock); @@ -340,8 +340,7 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd) /* Check for a non-mountpoint directory with no contents */ spin_lock(&dcache_lock); if (S_ISDIR(dentry->d_inode->i_mode) && - !d_mountpoint(dentry) && - __simple_empty(dentry)) { + !d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) { DPRINTK("dentry=%p %.*s, emptydir", dentry, dentry->d_name.len, dentry->d_name.name); spin_unlock(&dcache_lock); -- 2.25.1