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 <viro@zeniv.linux.org.uk>
diff --git a/fs/dcache.c b/fs/dcache.c
index 6a629f5..d9450bd 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2339,19 +2339,15 @@
}
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 @@
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 @@
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 @@
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 @@
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 @@
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 */