From 15d3c589f6305c50a705572dbb33620c5cba416c Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 29 Jul 2016 17:45:21 -0400 Subject: fold _d_rehash() and __d_rehash() together The only place where we feed to __d_rehash() something other than d_hash(dentry->d_name.hash) is __d_move(), where we give it d_hash of another dentry. Postpone rehashing until we'd switched the names and we are rid of that exception, along with the need to keep _d_rehash() and __d_rehash() separate. Signed-off-by: Al Viro --- fs/dcache.c | 34 +++++++++++----------------------- 1 file changed, 11 insertions(+), 23 deletions(-) (limited to 'fs/dcache.c') diff --git a/fs/dcache.c b/fs/dcache.c index 6a629f50c3cf..d9450bd496ac 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2339,19 +2339,15 @@ again: } EXPORT_SYMBOL(d_delete); -static void __d_rehash(struct dentry * entry, struct hlist_bl_head *b) +static void __d_rehash(struct dentry *entry) { + struct hlist_bl_head *b = d_hash(entry->d_name.hash); BUG_ON(!d_unhashed(entry)); hlist_bl_lock(b); hlist_bl_add_head_rcu(&entry->d_hash, b); hlist_bl_unlock(b); } -static void _d_rehash(struct dentry * entry) -{ - __d_rehash(entry, d_hash(entry->d_name.hash)); -} - /** * d_rehash - add an entry back to the hash * @entry: dentry to add to the hash @@ -2362,7 +2358,7 @@ static void _d_rehash(struct dentry * entry) void d_rehash(struct dentry * entry) { spin_lock(&entry->d_lock); - _d_rehash(entry); + __d_rehash(entry); spin_unlock(&entry->d_lock); } EXPORT_SYMBOL(d_rehash); @@ -2536,7 +2532,7 @@ static inline void __d_add(struct dentry *dentry, struct inode *inode) raw_write_seqcount_end(&dentry->d_seq); fsnotify_update_flags(dentry); } - _d_rehash(dentry); + __d_rehash(dentry); if (dir) end_dir_add(dir, n); spin_unlock(&dentry->d_lock); @@ -2598,7 +2594,7 @@ struct dentry *d_exact_alias(struct dentry *entry, struct inode *inode) alias = NULL; } else { __dget_dlock(alias); - _d_rehash(alias); + __d_rehash(alias); spin_unlock(&alias->d_lock); } spin_unlock(&inode->i_lock); @@ -2782,23 +2778,10 @@ static void __d_move(struct dentry *dentry, struct dentry *target, write_seqcount_begin(&dentry->d_seq); write_seqcount_begin_nested(&target->d_seq, DENTRY_D_LOCK_NESTED); + /* unhash both */ /* __d_drop does write_seqcount_barrier, but they're OK to nest. */ - - /* - * Move the dentry to the target hash queue. Don't bother checking - * for the same hash queue because of how unlikely it is. - */ __d_drop(dentry); - __d_rehash(dentry, d_hash(target->d_name.hash)); - - /* - * Unhash the target (d_delete() is not usable here). If exchanging - * the two dentries, then rehash onto the other's hash queue. - */ __d_drop(target); - if (exchange) { - __d_rehash(target, d_hash(dentry->d_name.hash)); - } /* Switch the names.. */ if (exchange) @@ -2806,6 +2789,11 @@ static void __d_move(struct dentry *dentry, struct dentry *target, else copy_name(dentry, target); + /* rehash in new place(s) */ + __d_rehash(dentry); + if (exchange) + __d_rehash(target); + /* ... and switch them in the tree */ if (IS_ROOT(dentry)) { /* splicing a tree */ -- cgit