diff options
Diffstat (limited to 'fs/dcache.c')
| -rw-r--r-- | fs/dcache.c | 48 |
1 files changed, 24 insertions, 24 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 7559057..9df8b86 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -301,6 +301,27 @@ static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent) return parent; } +/* + * Unhash a dentry without inserting an RCU walk barrier or checking that + * dentry->d_lock is locked. The caller must take care of that, if + * appropriate. + */ +static void __d_shrink(struct dentry *dentry) +{ + if (!d_unhashed(dentry)) { + struct hlist_bl_head *b; + if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED)) + b = &dentry->d_sb->s_anon; + else + b = d_hash(dentry->d_parent, dentry->d_name.hash); + + hlist_bl_lock(b); + __hlist_bl_del(&dentry->d_hash); + dentry->d_hash.pprev = NULL; + hlist_bl_unlock(b); + } +} + /** * d_drop - drop a dentry * @dentry: dentry to drop @@ -319,17 +340,7 @@ static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent) void __d_drop(struct dentry *dentry) { if (!d_unhashed(dentry)) { - struct hlist_bl_head *b; - if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED)) - b = &dentry->d_sb->s_anon; - else - b = d_hash(dentry->d_parent, dentry->d_name.hash); - - hlist_bl_lock(b); - __hlist_bl_del(&dentry->d_hash); - dentry->d_hash.pprev = NULL; - hlist_bl_unlock(b); - + __d_shrink(dentry); dentry_rcuwalk_barrier(dentry); } } @@ -832,10 +843,8 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) BUG_ON(!IS_ROOT(dentry)); /* detach this root from the system */ - spin_lock(&dentry->d_lock); dentry_lru_del(dentry); - __d_drop(dentry); - spin_unlock(&dentry->d_lock); + __d_shrink(dentry); for (;;) { /* descend to the first leaf in the current subtree */ @@ -844,16 +853,11 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) /* this is a branch with children - detach all of them * from the system in one go */ - spin_lock(&dentry->d_lock); list_for_each_entry(loop, &dentry->d_subdirs, d_u.d_child) { - spin_lock_nested(&loop->d_lock, - DENTRY_D_LOCK_NESTED); dentry_lru_del(loop); - __d_drop(loop); - spin_unlock(&loop->d_lock); + __d_shrink(loop); } - spin_unlock(&dentry->d_lock); /* move to the first child */ dentry = list_entry(dentry->d_subdirs.next, @@ -885,10 +889,8 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) list_del(&dentry->d_u.d_child); } else { parent = dentry->d_parent; - spin_lock(&parent->d_lock); parent->d_count--; list_del(&dentry->d_u.d_child); - spin_unlock(&parent->d_lock); } inode = dentry->d_inode; @@ -935,9 +937,7 @@ void shrink_dcache_for_umount(struct super_block *sb) dentry = sb->s_root; sb->s_root = NULL; - spin_lock(&dentry->d_lock); dentry->d_count--; - spin_unlock(&dentry->d_lock); shrink_dcache_for_umount_subtree(dentry); while (!hlist_bl_empty(&sb->s_anon)) { |
