diff --git a/fs/dcache.c b/fs/dcache.c index bf3c4f9569eb953e5ef939a3ff5804a8b0c90995..ca8e9cd60f87ec1770af68bba09731c0227f42de 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -229,7 +229,7 @@ static void __d_free(struct rcu_head *head) */ static void d_free(struct dentry *dentry) { - BUG_ON(dentry->d_lockref.count); + BUG_ON((int)dentry->d_lockref.count > 0); this_cpu_dec(nr_dentry); if (dentry->d_op && dentry->d_op->d_release) dentry->d_op->d_release(dentry); @@ -445,7 +445,7 @@ EXPORT_SYMBOL(d_drop); * If ref is non-zero, then decrement the refcount too. * Returns dentry requiring refcount drop, or NULL if we're done. */ -static inline struct dentry *dentry_kill(struct dentry *dentry, int ref) +static inline struct dentry *dentry_kill(struct dentry *dentry) __releases(dentry->d_lock) { struct inode *inode; @@ -468,8 +468,11 @@ static inline struct dentry *dentry_kill(struct dentry *dentry, int ref) goto relock; } - if (ref) - dentry->d_lockref.count--; + /* + * The dentry is now unrecoverably dead to the world. + */ + lockref_mark_dead(&dentry->d_lockref); + /* * inform the fs via d_prune that this dentry is about to be * unhashed and destroyed. @@ -535,7 +538,7 @@ void dput(struct dentry *dentry) return; kill_it: - dentry = dentry_kill(dentry, 1); + dentry = dentry_kill(dentry); if (dentry) goto repeat; } @@ -760,7 +763,7 @@ static void try_prune_one_dentry(struct dentry *dentry) { struct dentry *parent; - parent = dentry_kill(dentry, 0); + parent = dentry_kill(dentry); /* * If dentry_kill returns NULL, we have nothing more to do. * if it returns the same dentry, trylocks failed. In either @@ -781,7 +784,7 @@ static void try_prune_one_dentry(struct dentry *dentry) while (dentry) { if (lockref_put_or_lock(&dentry->d_lockref)) return; - dentry = dentry_kill(dentry, 1); + dentry = dentry_kill(dentry); } } diff --git a/fs/namei.c b/fs/namei.c index f415c6683a837ac3cb1c5bf1d9600b6a3aec9d7e..cc4bcfaa8624172ff82b13789c871b470de78d3c 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -517,25 +517,12 @@ static inline void unlock_rcu_walk(void) */ static inline int d_rcu_to_refcount(struct dentry *dentry, seqcount_t *validate, unsigned seq) { - int gotref; - - gotref = lockref_get_or_lock(&dentry->d_lockref); - - /* Does the sequence number still match? */ - if (read_seqcount_retry(validate, seq)) { - if (gotref) - dput(dentry); - else - spin_unlock(&dentry->d_lock); - return -ECHILD; - } - - /* Get the ref now, if we couldn't get it originally */ - if (!gotref) { - dentry->d_lockref.count++; - spin_unlock(&dentry->d_lock); + if (likely(lockref_get_not_dead(&dentry->d_lockref))) { + if (!read_seqcount_retry(validate, seq)) + return 0; + dput(dentry); } - return 0; + return -ECHILD; } /**