From 2d753e62b87ab2fc72bb4ff5153791d32ff9c08e Mon Sep 17 00:00:00 2001 From: Ian Kent Date: Mon, 27 Mar 2006 01:14:44 -0800 Subject: [PATCH] [PATCH] autofs4: can't mount due to mount point dir not empty Addresse a problem where stale dentrys stop mounts from happening. When a mount point directory is pre-created and a non-existent entry within it is requested a dentry ends up being created within the mount point directory which stops future mounts. The problem is solved by ignoring negative, unhashed dentrys in the mount point d_subdirs list. Additionally the apparent cacheing of -ENOENT returns from requests is removed. The test on d_time is a tautology and d_time is not initialised and has an unexpected value. In short it doesn't do what it's meant to. The cacheing of failed requests to the daemon is important and will be followed up later. Signed-off-by: Ian Kent Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/autofs4/autofs_i.h | 8 -------- fs/autofs4/root.c | 9 ++++----- 2 files changed, 4 insertions(+), 13 deletions(-) diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index f54c5b21f876..eea25934da62 100644 --- a/fs/autofs4/autofs_i.h +++ b/fs/autofs4/autofs_i.h @@ -41,14 +41,6 @@ #define AUTOFS_SUPER_MAGIC 0x0187 -/* - * If the daemon returns a negative response (AUTOFS_IOC_FAIL) then the - * kernel will keep the negative response cached for up to the time given - * here, although the time can be shorter if the kernel throws the dcache - * entry away. This probably should be settable from user space. - */ -#define AUTOFS_NEGATIVE_TIMEOUT (60*HZ) /* 1 minute */ - /* Unified info structure. This is pointed to by both the dentry and inode structures. Each file in the filesystem has an instance of this structure. It holds a reference to the dentry, so dentries are never diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index af9a4c6bbadf..c7ff35774344 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -294,14 +294,13 @@ static int try_to_fill_dentry(struct vfsmount *mnt, struct dentry *dentry, int f /* Turn this into a real negative dentry? */ if (status == -ENOENT) { - dentry->d_time = jiffies + AUTOFS_NEGATIVE_TIMEOUT; spin_lock(&dentry->d_lock); dentry->d_flags &= ~DCACHE_AUTOFS_PENDING; spin_unlock(&dentry->d_lock); - return 1; + return 0; } else if (status) { /* Return a negative dentry, but leave it "pending" */ - return 1; + return 0; } /* Trigger mount for path component or follow link */ } else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) || @@ -360,13 +359,13 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd) /* Negative dentry.. invalidate if "old" */ if (dentry->d_inode == NULL) - return (dentry->d_time - jiffies <= AUTOFS_NEGATIVE_TIMEOUT); + return 0; /* Check for a non-mountpoint directory with no contents */ spin_lock(&dcache_lock); if (S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry) && - list_empty(&dentry->d_subdirs)) { + simple_empty_nolock(dentry)) { DPRINTK("dentry=%p %.*s, emptydir", dentry, dentry->d_name.len, dentry->d_name.name); spin_unlock(&dcache_lock);