[PATCH] AUTOFS: Make sure all dentries refs are released before calling kill_anon_super()
Make sure all dentries refs are released before calling kill_anon_super() so
that the assumption that generic_shutdown_super() can completely destroy the
dentry tree for there will be no external references holds true.
What was being done in the put_super() superblock op, is now done in the
kill_sb() filesystem op instead, prior to calling kill_anon_super().
This makes the struct autofs_sb_info::root member variable redundant (since
sb->s_root is still available), and so that is removed. The calls to
shrink_dcache_sb() are also removed since they're also redundant as
shrink_dcache_for_umount() will now be called after the cleanup routine.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ian Kent <raven@themaw.net>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index 480ab17..b13f32c 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -94,7 +94,6 @@
struct autofs_sb_info {
u32 magic;
- struct dentry *root;
int pipefd;
struct file *pipe;
pid_t oz_pgrp;
@@ -229,4 +228,4 @@
}
void autofs4_dentry_release(struct dentry *);
-
+extern void autofs4_kill_sb(struct super_block *);
diff --git a/fs/autofs4/init.c b/fs/autofs4/init.c
index 5d91933..723a1c5e 100644
--- a/fs/autofs4/init.c
+++ b/fs/autofs4/init.c
@@ -24,7 +24,7 @@
.owner = THIS_MODULE,
.name = "autofs",
.get_sb = autofs_get_sb,
- .kill_sb = kill_anon_super,
+ .kill_sb = autofs4_kill_sb,
};
static int __init init_autofs4_fs(void)
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index 800ce87..51fd859 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -96,7 +96,7 @@
*/
static void autofs4_force_release(struct autofs_sb_info *sbi)
{
- struct dentry *this_parent = sbi->root;
+ struct dentry *this_parent = sbi->sb->s_root;
struct list_head *next;
spin_lock(&dcache_lock);
@@ -127,7 +127,7 @@
spin_lock(&dcache_lock);
}
- if (this_parent != sbi->root) {
+ if (this_parent != sbi->sb->s_root) {
struct dentry *dentry = this_parent;
next = this_parent->d_u.d_child.next;
@@ -140,15 +140,9 @@
goto resume;
}
spin_unlock(&dcache_lock);
-
- dput(sbi->root);
- sbi->root = NULL;
- shrink_dcache_sb(sbi->sb);
-
- return;
}
-static void autofs4_put_super(struct super_block *sb)
+void autofs4_kill_sb(struct super_block *sb)
{
struct autofs_sb_info *sbi = autofs4_sbi(sb);
@@ -163,6 +157,7 @@
kfree(sbi);
DPRINTK("shutting down");
+ kill_anon_super(sb);
}
static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)
@@ -189,7 +184,6 @@
}
static struct super_operations autofs4_sops = {
- .put_super = autofs4_put_super,
.statfs = simple_statfs,
.show_options = autofs4_show_options,
};
@@ -315,7 +309,6 @@
s->s_fs_info = sbi;
sbi->magic = AUTOFS_SBI_MAGIC;
- sbi->root = NULL;
sbi->pipefd = -1;
sbi->catatonic = 0;
sbi->exp_timeout = 0;
@@ -397,13 +390,6 @@
sbi->pipefd = pipefd;
/*
- * Take a reference to the root dentry so we get a chance to
- * clean up the dentry tree on umount.
- * See autofs4_force_release.
- */
- sbi->root = dget(root);
-
- /*
* Success! Install the root dentry now to indicate completion.
*/
s->s_root = root;
diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index ce103e7..c0a6c8d 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -45,7 +45,6 @@
fput(sbi->pipe); /* Close the pipe */
sbi->pipe = NULL;
}
- shrink_dcache_sb(sbi->sb);
}
static int autofs4_write(struct file *file, const void *addr, int bytes)