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-rw-r--r--fs/autofs4/expire.c13
-rw-r--r--fs/dcache.c1
-rw-r--r--fs/namespace.c29
-rw-r--r--include/linux/dcache.h42
4 files changed, 58 insertions, 27 deletions
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index 2f7951d67d16..cc1d01365905 100644
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -295,7 +295,9 @@ struct dentry *autofs4_expire_direct(struct super_block *sb,
struct autofs_info *ino = autofs4_dentry_ino(root);
if (d_mountpoint(root)) {
ino->flags |= AUTOFS_INF_MOUNTPOINT;
- root->d_mounted--;
+ spin_lock(&root->d_lock);
+ root->d_flags &= ~DCACHE_MOUNTED;
+ spin_unlock(&root->d_lock);
}
ino->flags |= AUTOFS_INF_EXPIRING;
init_completion(&ino->expire_complete);
@@ -503,7 +505,14 @@ int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
spin_lock(&sbi->fs_lock);
if (ino->flags & AUTOFS_INF_MOUNTPOINT) {
- sb->s_root->d_mounted++;
+ spin_lock(&sb->s_root->d_lock);
+ /*
+ * If we haven't been expired away, then reset
+ * mounted status.
+ */
+ if (mnt->mnt_parent != mnt)
+ sb->s_root->d_flags |= DCACHE_MOUNTED;
+ spin_unlock(&sb->s_root->d_lock);
ino->flags &= ~AUTOFS_INF_MOUNTPOINT;
}
ino->flags &= ~AUTOFS_INF_EXPIRING;
diff --git a/fs/dcache.c b/fs/dcache.c
index 187fea040108..1d5cf511e1c7 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1265,7 +1265,6 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name)
dentry->d_sb = NULL;
dentry->d_op = NULL;
dentry->d_fsdata = NULL;
- dentry->d_mounted = 0;
INIT_HLIST_NODE(&dentry->d_hash);
INIT_LIST_HEAD(&dentry->d_lru);
INIT_LIST_HEAD(&dentry->d_subdirs);
diff --git a/fs/namespace.c b/fs/namespace.c
index 3dbfc072ec70..39a7d507fba0 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -492,6 +492,27 @@ static void __touch_mnt_namespace(struct mnt_namespace *ns)
}
/*
+ * Clear dentry's mounted state if it has no remaining mounts.
+ * vfsmount_lock must be held for write.
+ */
+static void dentry_reset_mounted(struct vfsmount *mnt, struct dentry *dentry)
+{
+ unsigned u;
+
+ for (u = 0; u < HASH_SIZE; u++) {
+ struct vfsmount *p;
+
+ list_for_each_entry(p, &mount_hashtable[u], mnt_hash) {
+ if (p->mnt_mountpoint == dentry)
+ return;
+ }
+ }
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags &= ~DCACHE_MOUNTED;
+ spin_unlock(&dentry->d_lock);
+}
+
+/*
* vfsmount lock must be held for write
*/
static void detach_mnt(struct vfsmount *mnt, struct path *old_path)
@@ -502,7 +523,7 @@ static void detach_mnt(struct vfsmount *mnt, struct path *old_path)
mnt->mnt_mountpoint = mnt->mnt_root;
list_del_init(&mnt->mnt_child);
list_del_init(&mnt->mnt_hash);
- old_path->dentry->d_mounted--;
+ dentry_reset_mounted(old_path->mnt, old_path->dentry);
}
/*
@@ -513,7 +534,9 @@ void mnt_set_mountpoint(struct vfsmount *mnt, struct dentry *dentry,
{
child_mnt->mnt_parent = mntget(mnt);
child_mnt->mnt_mountpoint = dget(dentry);
- dentry->d_mounted++;
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags |= DCACHE_MOUNTED;
+ spin_unlock(&dentry->d_lock);
}
/*
@@ -1073,7 +1096,7 @@ void umount_tree(struct vfsmount *mnt, int propagate, struct list_head *kill)
list_del_init(&p->mnt_child);
if (p->mnt_parent != p) {
p->mnt_parent->mnt_ghosts++;
- p->mnt_mountpoint->d_mounted--;
+ dentry_reset_mounted(p->mnt_parent, p->mnt_mountpoint);
}
change_mnt_propagation(p, MS_PRIVATE);
}
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index c2e7390289cc..e4414693065e 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -92,7 +92,6 @@ struct dentry {
unsigned int d_flags; /* protected by d_lock */
spinlock_t d_lock; /* per dentry lock */
seqcount_t d_seq; /* per dentry seqlock */
- int d_mounted;
struct inode *d_inode; /* Where the name belongs to - NULL is
* negative */
/*
@@ -156,33 +155,34 @@ struct dentry_operations {
/* d_flags entries */
#define DCACHE_AUTOFS_PENDING 0x0001 /* autofs: "under construction" */
-#define DCACHE_NFSFS_RENAMED 0x0002 /* this dentry has been "silly
- * renamed" and has to be
- * deleted on the last dput()
- */
-#define DCACHE_DISCONNECTED 0x0004
- /* This dentry is possibly not currently connected to the dcache tree,
- * in which case its parent will either be itself, or will have this
- * flag as well. nfsd will not use a dentry with this bit set, but will
- * first endeavour to clear the bit either by discovering that it is
- * connected, or by performing lookup operations. Any filesystem which
- * supports nfsd_operations MUST have a lookup function which, if it finds
- * a directory inode with a DCACHE_DISCONNECTED dentry, will d_move
- * that dentry into place and return that dentry rather than the passed one,
- * typically using d_splice_alias.
- */
+#define DCACHE_NFSFS_RENAMED 0x0002
+ /* this dentry has been "silly renamed" and has to be deleted on the last
+ * dput() */
+
+#define DCACHE_DISCONNECTED 0x0004
+ /* This dentry is possibly not currently connected to the dcache tree, in
+ * which case its parent will either be itself, or will have this flag as
+ * well. nfsd will not use a dentry with this bit set, but will first
+ * endeavour to clear the bit either by discovering that it is connected,
+ * or by performing lookup operations. Any filesystem which supports
+ * nfsd_operations MUST have a lookup function which, if it finds a
+ * directory inode with a DCACHE_DISCONNECTED dentry, will d_move that
+ * dentry into place and return that dentry rather than the passed one,
+ * typically using d_splice_alias. */
#define DCACHE_REFERENCED 0x0008 /* Recently used, don't discard. */
#define DCACHE_UNHASHED 0x0010
-
-#define DCACHE_INOTIFY_PARENT_WATCHED 0x0020 /* Parent inode is watched by inotify */
+#define DCACHE_INOTIFY_PARENT_WATCHED 0x0020
+ /* Parent inode is watched by inotify */
#define DCACHE_COOKIE 0x0040 /* For use by dcookie subsystem */
-
-#define DCACHE_FSNOTIFY_PARENT_WATCHED 0x0080 /* Parent inode is watched by some fsnotify listener */
+#define DCACHE_FSNOTIFY_PARENT_WATCHED 0x0080
+ /* Parent inode is watched by some fsnotify listener */
#define DCACHE_CANT_MOUNT 0x0100
#define DCACHE_GENOCIDE 0x0200
+#define DCACHE_MOUNTED 0x0400 /* is a mountpoint */
+
extern spinlock_t dcache_inode_lock;
extern seqlock_t rename_lock;
@@ -372,7 +372,7 @@ extern void dput(struct dentry *);
static inline int d_mountpoint(struct dentry *dentry)
{
- return dentry->d_mounted;
+ return dentry->d_flags & DCACHE_MOUNTED;
}
extern struct vfsmount *lookup_mnt(struct path *);
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