diff options
Diffstat (limited to 'fs/dcache.c')
| -rw-r--r-- | fs/dcache.c | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 0f1d93866e69..10988f7e5a23 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2364,6 +2364,22 @@ void d_rehash(struct dentry * entry) } EXPORT_SYMBOL(d_rehash); +static inline unsigned start_dir_add(struct inode *dir) +{ + + for (;;) { + unsigned n = dir->i_dir_seq; + if (!(n & 1) && cmpxchg(&dir->i_dir_seq, n, n + 1) == n) + return n; + cpu_relax(); + } +} + +static inline void end_dir_add(struct inode *dir, unsigned n) +{ + smp_store_release(&dir->i_dir_seq, n + 2); +} + void __d_lookup_done(struct dentry *dentry) { dentry->d_flags &= ~DCACHE_PAR_LOOKUP; @@ -2375,9 +2391,14 @@ EXPORT_SYMBOL(__d_lookup_done); static inline void __d_add(struct dentry *dentry, struct inode *inode) { + struct inode *dir = NULL; + unsigned n; spin_lock(&dentry->d_lock); - if (unlikely(d_in_lookup(dentry))) + if (unlikely(d_in_lookup(dentry))) { + dir = dentry->d_parent->d_inode; + n = start_dir_add(dir); __d_lookup_done(dentry); + } if (inode) { unsigned add_flags = d_flags_for_inode(inode); hlist_add_head(&dentry->d_u.d_alias, &inode->i_dentry); @@ -2387,6 +2408,8 @@ static inline void __d_add(struct dentry *dentry, struct inode *inode) __fsnotify_d_instantiate(dentry); } _d_rehash(dentry); + if (dir) + end_dir_add(dir, n); spin_unlock(&dentry->d_lock); if (inode) spin_unlock(&inode->i_lock); @@ -2616,6 +2639,8 @@ static void dentry_unlock_for_move(struct dentry *dentry, struct dentry *target) static void __d_move(struct dentry *dentry, struct dentry *target, bool exchange) { + struct inode *dir = NULL; + unsigned n; if (!dentry->d_inode) printk(KERN_WARNING "VFS: moving negative dcache entry\n"); @@ -2623,8 +2648,11 @@ static void __d_move(struct dentry *dentry, struct dentry *target, BUG_ON(d_ancestor(target, dentry)); dentry_lock_for_move(dentry, target); - if (unlikely(d_in_lookup(target))) + if (unlikely(d_in_lookup(target))) { + dir = target->d_parent->d_inode; + n = start_dir_add(dir); __d_lookup_done(target); + } write_seqcount_begin(&dentry->d_seq); write_seqcount_begin_nested(&target->d_seq, DENTRY_D_LOCK_NESTED); @@ -2674,6 +2702,8 @@ static void __d_move(struct dentry *dentry, struct dentry *target, write_seqcount_end(&target->d_seq); write_seqcount_end(&dentry->d_seq); + if (dir) + end_dir_add(dir, n); dentry_unlock_for_move(dentry, target); } |