diff --git a/fs/dcache.c b/fs/dcache.c index 7108c15685dddc352c30f41e0dba427c751e1449..d600a0af3b2e3fee04b9dce0b610cf88c17c0123 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -164,8 +164,8 @@ static void d_free(struct dentry *dentry) if (dentry->d_op && dentry->d_op->d_release) dentry->d_op->d_release(dentry); - /* if dentry was never inserted into hash, immediate free is OK */ - if (hlist_bl_unhashed(&dentry->d_hash)) + /* if dentry was never visible to RCU, immediate free is OK */ + if (!(dentry->d_flags & DCACHE_RCUACCESS)) __d_free(&dentry->d_u.d_rcu); else call_rcu(&dentry->d_u.d_rcu, __d_free); @@ -327,28 +327,19 @@ static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent) */ void __d_drop(struct dentry *dentry) { - if (!(dentry->d_flags & DCACHE_UNHASHED)) { + if (!d_unhashed(dentry)) { struct hlist_bl_head *b; - if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED)) { + if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED)) b = &dentry->d_sb->s_anon; - spin_lock_bucket(b); - dentry->d_flags |= DCACHE_UNHASHED; - hlist_bl_del_init(&dentry->d_hash); - spin_unlock_bucket(b); - } else { - struct hlist_bl_head *b; + else b = d_hash(dentry->d_parent, dentry->d_name.hash); - spin_lock_bucket(b); - /* - * We may not actually need to put DCACHE_UNHASHED - * manipulations under the hash lock, but follow - * the principle of least surprise. - */ - dentry->d_flags |= DCACHE_UNHASHED; - hlist_bl_del_rcu(&dentry->d_hash); - spin_unlock_bucket(b); - dentry_rcuwalk_barrier(dentry); - } + + spin_lock_bucket(b); + __hlist_bl_del(&dentry->d_hash); + dentry->d_hash.pprev = NULL; + spin_unlock_bucket(b); + + dentry_rcuwalk_barrier(dentry); } } EXPORT_SYMBOL(__d_drop); @@ -1301,7 +1292,7 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name) dname[name->len] = 0; dentry->d_count = 1; - dentry->d_flags = DCACHE_UNHASHED; + dentry->d_flags = 0; spin_lock_init(&dentry->d_lock); seqcount_init(&dentry->d_seq); dentry->d_inode = NULL; @@ -1603,10 +1594,9 @@ struct dentry *d_obtain_alias(struct inode *inode) tmp->d_inode = inode; tmp->d_flags |= DCACHE_DISCONNECTED; list_add(&tmp->d_alias, &inode->i_dentry); - bit_spin_lock(0, (unsigned long *)&tmp->d_sb->s_anon.first); - tmp->d_flags &= ~DCACHE_UNHASHED; + spin_lock_bucket(&tmp->d_sb->s_anon); hlist_bl_add_head(&tmp->d_hash, &tmp->d_sb->s_anon); - __bit_spin_unlock(0, (unsigned long *)&tmp->d_sb->s_anon.first); + spin_unlock_bucket(&tmp->d_sb->s_anon); spin_unlock(&tmp->d_lock); spin_unlock(&inode->i_lock); security_d_instantiate(tmp, inode); @@ -2087,7 +2077,7 @@ static void __d_rehash(struct dentry * entry, struct hlist_bl_head *b) { BUG_ON(!d_unhashed(entry)); spin_lock_bucket(b); - entry->d_flags &= ~DCACHE_UNHASHED; + entry->d_flags |= DCACHE_RCUACCESS; hlist_bl_add_head_rcu(&entry->d_hash, b); spin_unlock_bucket(b); } diff --git a/include/linux/dcache.h b/include/linux/dcache.h index f2afed4fa9454776c79611d52755121dff749342..19d90a55541d99c37ea6d6c78040b9979dc38116 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -197,7 +197,7 @@ struct dentry_operations { * typically using d_splice_alias. */ #define DCACHE_REFERENCED 0x0008 /* Recently used, don't discard. */ -#define DCACHE_UNHASHED 0x0010 +#define DCACHE_RCUACCESS 0x0010 /* Entry has ever been RCU-visible */ #define DCACHE_INOTIFY_PARENT_WATCHED 0x0020 /* Parent inode is watched by inotify */ @@ -384,7 +384,7 @@ extern struct dentry *dget_parent(struct dentry *dentry); static inline int d_unhashed(struct dentry *dentry) { - return (dentry->d_flags & DCACHE_UNHASHED); + return hlist_bl_unhashed(&dentry->d_hash); } static inline int d_unlinked(struct dentry *dentry)