diff --git a/Documentation/admin-guide/sysctl/fs.rst b/Documentation/admin-guide/sysctl/fs.rst index 47499a1742bd..30c61474dec5 100644 --- a/Documentation/admin-guide/sysctl/fs.rst +++ b/Documentation/admin-guide/sysctl/fs.rst @@ -38,6 +38,11 @@ requests. ``aio-max-nr`` allows you to change the maximum value ``aio-max-nr`` does not result in the pre-allocation or re-sizing of any kernel data structures. +dentry-negative +---------------------------- + +Policy for negative dentries. Set to 1 to to always delete the dentry when a +file is removed, and 0 to disable it. By default, this behavior is disabled. dentry-state ------------ diff --git a/fs/dcache.c b/fs/dcache.c index 0f6b16ba30d0..0d7d1bfa23bd 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -135,6 +135,7 @@ struct dentry_stat_t { static DEFINE_PER_CPU(long, nr_dentry); static DEFINE_PER_CPU(long, nr_dentry_unused); static DEFINE_PER_CPU(long, nr_dentry_negative); +static int dentry_negative_policy; #if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS) /* Statistics gathering. */ @@ -199,6 +200,15 @@ static struct ctl_table fs_dcache_sysctls[] = { .mode = 0444, .proc_handler = proc_nr_dentry, }, + { + .procname = "dentry-negative", + .data = &dentry_negative_policy, + .maxlen = sizeof(dentry_negative_policy), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, }; static int __init init_fs_dcache_sysctls(void) @@ -2401,6 +2411,8 @@ void d_delete(struct dentry * dentry) * Are we the only user? */ if (dentry->d_lockref.count == 1) { + if (dentry_negative_policy) + __d_drop(dentry); dentry->d_flags &= ~DCACHE_CANT_MOUNT; dentry_unlink_inode(dentry); } else {